| /* |
| * NSA Security-Enhanced Linux (SELinux) security module |
| * |
| * This file contains the SELinux hook function implementations. |
| * |
| * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> |
| * Chris Vance, <cvance@nai.com> |
| * Wayne Salamon, <wsalamon@nai.com> |
| * James Morris <jmorris@redhat.com> |
| * |
| * Copyright (C) 2001,2002 Networks Associates Technology, Inc. |
| * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
| * Eric Paris <eparis@redhat.com> |
| * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
| * <dgoeddel@trustedcs.com> |
| * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
| * Paul Moore <paul.moore@hp.com> |
| * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
| * Yuichi Nakamura <ynakam@hitachisoft.jp> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2, |
| * as published by the Free Software Foundation. |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/tracehook.h> |
| #include <linux/errno.h> |
| #include <linux/sched.h> |
| #include <linux/security.h> |
| #include <linux/xattr.h> |
| #include <linux/capability.h> |
| #include <linux/unistd.h> |
| #include <linux/mm.h> |
| #include <linux/mman.h> |
| #include <linux/slab.h> |
| #include <linux/pagemap.h> |
| #include <linux/swap.h> |
| #include <linux/spinlock.h> |
| #include <linux/syscalls.h> |
| #include <linux/file.h> |
| #include <linux/fdtable.h> |
| #include <linux/namei.h> |
| #include <linux/mount.h> |
| #include <linux/proc_fs.h> |
| #include <linux/netfilter_ipv4.h> |
| #include <linux/netfilter_ipv6.h> |
| #include <linux/tty.h> |
| #include <net/icmp.h> |
| #include <net/ip.h> /* for local_port_range[] */ |
| #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
| #include <net/net_namespace.h> |
| #include <net/netlabel.h> |
| #include <linux/uaccess.h> |
| #include <asm/ioctls.h> |
| #include <asm/atomic.h> |
| #include <linux/bitops.h> |
| #include <linux/interrupt.h> |
| #include <linux/netdevice.h> /* for network interface checks */ |
| #include <linux/netlink.h> |
| #include <linux/tcp.h> |
| #include <linux/udp.h> |
| #include <linux/dccp.h> |
| #include <linux/quota.h> |
| #include <linux/un.h> /* for Unix socket types */ |
| #include <net/af_unix.h> /* for Unix socket types */ |
| #include <linux/parser.h> |
| #include <linux/nfs_mount.h> |
| #include <net/ipv6.h> |
| #include <linux/hugetlb.h> |
| #include <linux/personality.h> |
| #include <linux/sysctl.h> |
| #include <linux/audit.h> |
| #include <linux/string.h> |
| #include <linux/selinux.h> |
| #include <linux/mutex.h> |
| #include <linux/posix-timers.h> |
| #include <linux/syslog.h> |
| |
| #include "avc.h" |
| #include "objsec.h" |
| #include "netif.h" |
| #include "netnode.h" |
| #include "netport.h" |
| #include "xfrm.h" |
| #include "netlabel.h" |
| #include "audit.h" |
| |
| #define NUM_SEL_MNT_OPTS 5 |
| |
| extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); |
| extern struct security_operations *security_ops; |
| |
| /* SECMARK reference count */ |
| atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
| |
| #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
| int selinux_enforcing; |
| |
| static int __init enforcing_setup(char *str) |
| { |
| unsigned long enforcing; |
| if (!strict_strtoul(str, 0, &enforcing)) |
| selinux_enforcing = enforcing ? 1 : 0; |
| return 1; |
| } |
| __setup("enforcing=", enforcing_setup); |
| #endif |
| |
| #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM |
| int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; |
| |
| static int __init selinux_enabled_setup(char *str) |
| { |
| unsigned long enabled; |
| if (!strict_strtoul(str, 0, &enabled)) |
| selinux_enabled = enabled ? 1 : 0; |
| return 1; |
| } |
| __setup("selinux=", selinux_enabled_setup); |
| #else |
| int selinux_enabled = 1; |
| #endif |
| |
| static struct kmem_cache *sel_inode_cache; |
| |
| /** |
| * selinux_secmark_enabled - Check to see if SECMARK is currently enabled |
| * |
| * Description: |
| * This function checks the SECMARK reference counter to see if any SECMARK |
| * targets are currently configured, if the reference counter is greater than |
| * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is |
| * enabled, false (0) if SECMARK is disabled. |
| * |
| */ |
| static int selinux_secmark_enabled(void) |
| { |
| return (atomic_read(&selinux_secmark_refcount) > 0); |
| } |
| |
| /* |
| * initialise the security for the init task |
| */ |
| static void cred_init_security(void) |
| { |
| struct cred *cred = (struct cred *) current->real_cred; |
| struct task_security_struct *tsec; |
| |
| tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
| if (!tsec) |
| panic("SELinux: Failed to initialize initial task.\n"); |
| |
| tsec->osid = tsec->sid = SECINITSID_KERNEL; |
| cred->security = tsec; |
| } |
| |
| /* |
| * get the security ID of a set of credentials |
| */ |
| static inline u32 cred_sid(const struct cred *cred) |
| { |
| const struct task_security_struct *tsec; |
| |
| tsec = cred->security; |
| return tsec->sid; |
| } |
| |
| /* |
| * get the objective security ID of a task |
| */ |
| static inline u32 task_sid(const struct task_struct *task) |
| { |
| u32 sid; |
| |
| rcu_read_lock(); |
| sid = cred_sid(__task_cred(task)); |
| rcu_read_unlock(); |
| return sid; |
| } |
| |
| /* |
| * get the subjective security ID of the current task |
| */ |
| static inline u32 current_sid(void) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| |
| return tsec->sid; |
| } |
| |
| /* Allocate and free functions for each kind of security blob. */ |
| |
| static int inode_alloc_security(struct inode *inode) |
| { |
| struct inode_security_struct *isec; |
| u32 sid = current_sid(); |
| |
| isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
| if (!isec) |
| return -ENOMEM; |
| |
| mutex_init(&isec->lock); |
| INIT_LIST_HEAD(&isec->list); |
| isec->inode = inode; |
| isec->sid = SECINITSID_UNLABELED; |
| isec->sclass = SECCLASS_FILE; |
| isec->task_sid = sid; |
| inode->i_security = isec; |
| |
| return 0; |
| } |
| |
| static void inode_free_security(struct inode *inode) |
| { |
| struct inode_security_struct *isec = inode->i_security; |
| struct superblock_security_struct *sbsec = inode->i_sb->s_security; |
| |
| spin_lock(&sbsec->isec_lock); |
| if (!list_empty(&isec->list)) |
| list_del_init(&isec->list); |
| spin_unlock(&sbsec->isec_lock); |
| |
| inode->i_security = NULL; |
| kmem_cache_free(sel_inode_cache, isec); |
| } |
| |
| static int file_alloc_security(struct file *file) |
| { |
| struct file_security_struct *fsec; |
| u32 sid = current_sid(); |
| |
| fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
| if (!fsec) |
| return -ENOMEM; |
| |
| fsec->sid = sid; |
| fsec->fown_sid = sid; |
| file->f_security = fsec; |
| |
| return 0; |
| } |
| |
| static void file_free_security(struct file *file) |
| { |
| struct file_security_struct *fsec = file->f_security; |
| file->f_security = NULL; |
| kfree(fsec); |
| } |
| |
| static int superblock_alloc_security(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec; |
| |
| sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
| if (!sbsec) |
| return -ENOMEM; |
| |
| mutex_init(&sbsec->lock); |
| INIT_LIST_HEAD(&sbsec->isec_head); |
| spin_lock_init(&sbsec->isec_lock); |
| sbsec->sb = sb; |
| sbsec->sid = SECINITSID_UNLABELED; |
| sbsec->def_sid = SECINITSID_FILE; |
| sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
| sb->s_security = sbsec; |
| |
| return 0; |
| } |
| |
| static void superblock_free_security(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = sb->s_security; |
| sb->s_security = NULL; |
| kfree(sbsec); |
| } |
| |
| /* The security server must be initialized before |
| any labeling or access decisions can be provided. */ |
| extern int ss_initialized; |
| |
| /* The file system's label must be initialized prior to use. */ |
| |
| static const char *labeling_behaviors[6] = { |
| "uses xattr", |
| "uses transition SIDs", |
| "uses task SIDs", |
| "uses genfs_contexts", |
| "not configured for labeling", |
| "uses mountpoint labeling", |
| }; |
| |
| static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
| |
| static inline int inode_doinit(struct inode *inode) |
| { |
| return inode_doinit_with_dentry(inode, NULL); |
| } |
| |
| enum { |
| Opt_error = -1, |
| Opt_context = 1, |
| Opt_fscontext = 2, |
| Opt_defcontext = 3, |
| Opt_rootcontext = 4, |
| Opt_labelsupport = 5, |
| }; |
| |
| static const match_table_t tokens = { |
| {Opt_context, CONTEXT_STR "%s"}, |
| {Opt_fscontext, FSCONTEXT_STR "%s"}, |
| {Opt_defcontext, DEFCONTEXT_STR "%s"}, |
| {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, |
| {Opt_labelsupport, LABELSUPP_STR}, |
| {Opt_error, NULL}, |
| }; |
| |
| #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" |
| |
| static int may_context_mount_sb_relabel(u32 sid, |
| struct superblock_security_struct *sbsec, |
| const struct cred *cred) |
| { |
| const struct task_security_struct *tsec = cred->security; |
| int rc; |
| |
| rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__RELABELFROM, NULL); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__RELABELTO, NULL); |
| return rc; |
| } |
| |
| static int may_context_mount_inode_relabel(u32 sid, |
| struct superblock_security_struct *sbsec, |
| const struct cred *cred) |
| { |
| const struct task_security_struct *tsec = cred->security; |
| int rc; |
| rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__RELABELFROM, NULL); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, |
| FILESYSTEM__ASSOCIATE, NULL); |
| return rc; |
| } |
| |
| static int sb_finish_set_opts(struct super_block *sb) |
| { |
| struct superblock_security_struct *sbsec = sb->s_security; |
| struct dentry *root = sb->s_root; |
| struct inode *root_inode = root->d_inode; |
| int rc = 0; |
| |
| if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
| /* Make sure that the xattr handler exists and that no |
| error other than -ENODATA is returned by getxattr on |
| the root directory. -ENODATA is ok, as this may be |
| the first boot of the SELinux kernel before we have |
| assigned xattr values to the filesystem. */ |
| if (!root_inode->i_op->getxattr) { |
| printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
| "xattr support\n", sb->s_id, sb->s_type->name); |
| rc = -EOPNOTSUPP; |
| goto out; |
| } |
| rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); |
| if (rc < 0 && rc != -ENODATA) { |
| if (rc == -EOPNOTSUPP) |
| printk(KERN_WARNING "SELinux: (dev %s, type " |
| "%s) has no security xattr handler\n", |
| sb->s_id, sb->s_type->name); |
| else |
| printk(KERN_WARNING "SELinux: (dev %s, type " |
| "%s) getxattr errno %d\n", sb->s_id, |
| sb->s_type->name, -rc); |
| goto out; |
| } |
| } |
| |
| sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); |
| |
| if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
| printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", |
| sb->s_id, sb->s_type->name); |
| else |
| printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", |
| sb->s_id, sb->s_type->name, |
| labeling_behaviors[sbsec->behavior-1]); |
| |
| if (sbsec->behavior == SECURITY_FS_USE_GENFS || |
| sbsec->behavior == SECURITY_FS_USE_MNTPOINT || |
| sbsec->behavior == SECURITY_FS_USE_NONE || |
| sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
| sbsec->flags &= ~SE_SBLABELSUPP; |
| |
| /* Special handling for sysfs. Is genfs but also has setxattr handler*/ |
| if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) |
| sbsec->flags |= SE_SBLABELSUPP; |
| |
| /* Initialize the root inode. */ |
| rc = inode_doinit_with_dentry(root_inode, root); |
| |
| /* Initialize any other inodes associated with the superblock, e.g. |
| inodes created prior to initial policy load or inodes created |
| during get_sb by a pseudo filesystem that directly |
| populates itself. */ |
| spin_lock(&sbsec->isec_lock); |
| next_inode: |
| if (!list_empty(&sbsec->isec_head)) { |
| struct inode_security_struct *isec = |
| list_entry(sbsec->isec_head.next, |
| struct inode_security_struct, list); |
| struct inode *inode = isec->inode; |
| spin_unlock(&sbsec->isec_lock); |
| inode = igrab(inode); |
| if (inode) { |
| if (!IS_PRIVATE(inode)) |
| inode_doinit(inode); |
| iput(inode); |
| } |
| spin_lock(&sbsec->isec_lock); |
| list_del_init(&isec->list); |
| goto next_inode; |
| } |
| spin_unlock(&sbsec->isec_lock); |
| out: |
| return rc; |
| } |
| |
| /* |
| * This function should allow an FS to ask what it's mount security |
| * options were so it can use those later for submounts, displaying |
| * mount options, or whatever. |
| */ |
| static int selinux_get_mnt_opts(const struct super_block *sb, |
| struct security_mnt_opts *opts) |
| { |
| int rc = 0, i; |
| struct superblock_security_struct *sbsec = sb->s_security; |
| char *context = NULL; |
| u32 len; |
| char tmp; |
| |
| security_init_mnt_opts(opts); |
| |
| if (!(sbsec->flags & SE_SBINITIALIZED)) |
| return -EINVAL; |
| |
| if (!ss_initialized) |
| return -EINVAL; |
| |
| tmp = sbsec->flags & SE_MNTMASK; |
| /* count the number of mount options for this sb */ |
| for (i = 0; i < 8; i++) { |
| if (tmp & 0x01) |
| opts->num_mnt_opts++; |
| tmp >>= 1; |
| } |
| /* Check if the Label support flag is set */ |
| if (sbsec->flags & SE_SBLABELSUPP) |
| opts->num_mnt_opts++; |
| |
| opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
| if (!opts->mnt_opts) { |
| rc = -ENOMEM; |
| goto out_free; |
| } |
| |
| opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
| if (!opts->mnt_opts_flags) { |
| rc = -ENOMEM; |
| goto out_free; |
| } |
| |
| i = 0; |
| if (sbsec->flags & FSCONTEXT_MNT) { |
| rc = security_sid_to_context(sbsec->sid, &context, &len); |
| if (rc) |
| goto out_free; |
| opts->mnt_opts[i] = context; |
| opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; |
| } |
| if (sbsec->flags & CONTEXT_MNT) { |
| rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); |
| if (rc) |
| goto out_free; |
| opts->mnt_opts[i] = context; |
| opts->mnt_opts_flags[i++] = CONTEXT_MNT; |
| } |
| if (sbsec->flags & DEFCONTEXT_MNT) { |
| rc = security_sid_to_context(sbsec->def_sid, &context, &len); |
| if (rc) |
| goto out_free; |
| opts->mnt_opts[i] = context; |
| opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; |
| } |
| if (sbsec->flags & ROOTCONTEXT_MNT) { |
| struct inode *root = sbsec->sb->s_root->d_inode; |
| struct inode_security_struct *isec = root->i_security; |
| |
| rc = security_sid_to_context(isec->sid, &context, &len); |
| if (rc) |
| goto out_free; |
| opts->mnt_opts[i] = context; |
| opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; |
| } |
| if (sbsec->flags & SE_SBLABELSUPP) { |
| opts->mnt_opts[i] = NULL; |
| opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; |
| } |
| |
| BUG_ON(i != opts->num_mnt_opts); |
| |
| return 0; |
| |
| out_free: |
| security_free_mnt_opts(opts); |
| return rc; |
| } |
| |
| static int bad_option(struct superblock_security_struct *sbsec, char flag, |
| u32 old_sid, u32 new_sid) |
| { |
| char mnt_flags = sbsec->flags & SE_MNTMASK; |
| |
| /* check if the old mount command had the same options */ |
| if (sbsec->flags & SE_SBINITIALIZED) |
| if (!(sbsec->flags & flag) || |
| (old_sid != new_sid)) |
| return 1; |
| |
| /* check if we were passed the same options twice, |
| * aka someone passed context=a,context=b |
| */ |
| if (!(sbsec->flags & SE_SBINITIALIZED)) |
| if (mnt_flags & flag) |
| return 1; |
| return 0; |
| } |
| |
| /* |
| * Allow filesystems with binary mount data to explicitly set mount point |
| * labeling information. |
| */ |
| static int selinux_set_mnt_opts(struct super_block *sb, |
| struct security_mnt_opts *opts) |
| { |
| const struct cred *cred = current_cred(); |
| int rc = 0, i; |
| struct superblock_security_struct *sbsec = sb->s_security; |
| const char *name = sb->s_type->name; |
| struct inode *inode = sbsec->sb->s_root->d_inode; |
| struct inode_security_struct *root_isec = inode->i_security; |
| u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
| u32 defcontext_sid = 0; |
| char **mount_options = opts->mnt_opts; |
| int *flags = opts->mnt_opts_flags; |
| int num_opts = opts->num_mnt_opts; |
| |
| mutex_lock(&sbsec->lock); |
| |
| if (!ss_initialized) { |
| if (!num_opts) { |
| /* Defer initialization until selinux_complete_init, |
| after the initial policy is loaded and the security |
| server is ready to handle calls. */ |
| goto out; |
| } |
| rc = -EINVAL; |
| printk(KERN_WARNING "SELinux: Unable to set superblock options " |
| "before the security server is initialized\n"); |
| goto out; |
| } |
| |
| /* |
| * Binary mount data FS will come through this function twice. Once |
| * from an explicit call and once from the generic calls from the vfs. |
| * Since the generic VFS calls will not contain any security mount data |
| * we need to skip the double mount verification. |
| * |
| * This does open a hole in which we will not notice if the first |
| * mount using this sb set explict options and a second mount using |
| * this sb does not set any security options. (The first options |
| * will be used for both mounts) |
| */ |
| if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
| && (num_opts == 0)) |
| goto out; |
| |
| /* |
| * parse the mount options, check if they are valid sids. |
| * also check if someone is trying to mount the same sb more |
| * than once with different security options. |
| */ |
| for (i = 0; i < num_opts; i++) { |
| u32 sid; |
| |
| if (flags[i] == SE_SBLABELSUPP) |
| continue; |
| rc = security_context_to_sid(mount_options[i], |
| strlen(mount_options[i]), &sid); |
| if (rc) { |
| printk(KERN_WARNING "SELinux: security_context_to_sid" |
| "(%s) failed for (dev %s, type %s) errno=%d\n", |
| mount_options[i], sb->s_id, name, rc); |
| goto out; |
| } |
| switch (flags[i]) { |
| case FSCONTEXT_MNT: |
| fscontext_sid = sid; |
| |
| if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
| fscontext_sid)) |
| goto out_double_mount; |
| |
| sbsec->flags |= FSCONTEXT_MNT; |
| break; |
| case CONTEXT_MNT: |
| context_sid = sid; |
| |
| if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
| context_sid)) |
| goto out_double_mount; |
| |
| sbsec->flags |= CONTEXT_MNT; |
| break; |
| case ROOTCONTEXT_MNT: |
| rootcontext_sid = sid; |
| |
| if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
| rootcontext_sid)) |
| goto out_double_mount; |
| |
| sbsec->flags |= ROOTCONTEXT_MNT; |
| |
| break; |
| case DEFCONTEXT_MNT: |
| defcontext_sid = sid; |
| |
| if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
| defcontext_sid)) |
| goto out_double_mount; |
| |
| sbsec->flags |= DEFCONTEXT_MNT; |
| |
| break; |
| default: |
| rc = -EINVAL; |
| goto out; |
| } |
| } |
| |
| if (sbsec->flags & SE_SBINITIALIZED) { |
| /* previously mounted with options, but not on this attempt? */ |
| if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
| goto out_double_mount; |
| rc = 0; |
| goto out; |
| } |
| |
| if (strcmp(sb->s_type->name, "proc") == 0) |
| sbsec->flags |= SE_SBPROC; |
| |
| /* Determine the labeling behavior to use for this filesystem type. */ |
| rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); |
| if (rc) { |
| printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", |
| __func__, sb->s_type->name, rc); |
| goto out; |
| } |
| |
| /* sets the context of the superblock for the fs being mounted. */ |
| if (fscontext_sid) { |
| rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
| if (rc) |
| goto out; |
| |
| sbsec->sid = fscontext_sid; |
| } |
| |
| /* |
| * Switch to using mount point labeling behavior. |
| * sets the label used on all file below the mountpoint, and will set |
| * the superblock context if not already set. |
| */ |
| if (context_sid) { |
| if (!fscontext_sid) { |
| rc = may_context_mount_sb_relabel(context_sid, sbsec, |
| cred); |
| if (rc) |
| goto out; |
| sbsec->sid = context_sid; |
| } else { |
| rc = may_context_mount_inode_relabel(context_sid, sbsec, |
| cred); |
| if (rc) |
| goto out; |
| } |
| if (!rootcontext_sid) |
| rootcontext_sid = context_sid; |
| |
| sbsec->mntpoint_sid = context_sid; |
| sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
| } |
| |
| if (rootcontext_sid) { |
| rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
| cred); |
| if (rc) |
| goto out; |
| |
| root_isec->sid = rootcontext_sid; |
| root_isec->initialized = 1; |
| } |
| |
| if (defcontext_sid) { |
| if (sbsec->behavior != SECURITY_FS_USE_XATTR) { |
| rc = -EINVAL; |
| printk(KERN_WARNING "SELinux: defcontext option is " |
| "invalid for this filesystem type\n"); |
| goto out; |
| } |
| |
| if (defcontext_sid != sbsec->def_sid) { |
| rc = may_context_mount_inode_relabel(defcontext_sid, |
| sbsec, cred); |
| if (rc) |
| goto out; |
| } |
| |
| sbsec->def_sid = defcontext_sid; |
| } |
| |
| rc = sb_finish_set_opts(sb); |
| out: |
| mutex_unlock(&sbsec->lock); |
| return rc; |
| out_double_mount: |
| rc = -EINVAL; |
| printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " |
| "security settings for (dev %s, type %s)\n", sb->s_id, name); |
| goto out; |
| } |
| |
| static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
| struct super_block *newsb) |
| { |
| const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
| struct superblock_security_struct *newsbsec = newsb->s_security; |
| |
| int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
| int set_context = (oldsbsec->flags & CONTEXT_MNT); |
| int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); |
| |
| /* |
| * if the parent was able to be mounted it clearly had no special lsm |
| * mount options. thus we can safely deal with this superblock later |
| */ |
| if (!ss_initialized) |
| return; |
| |
| /* how can we clone if the old one wasn't set up?? */ |
| BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
| |
| /* if fs is reusing a sb, just let its options stand... */ |
| if (newsbsec->flags & SE_SBINITIALIZED) |
| return; |
| |
| mutex_lock(&newsbsec->lock); |
| |
| newsbsec->flags = oldsbsec->flags; |
| |
| newsbsec->sid = oldsbsec->sid; |
| newsbsec->def_sid = oldsbsec->def_sid; |
| newsbsec->behavior = oldsbsec->behavior; |
| |
| if (set_context) { |
| u32 sid = oldsbsec->mntpoint_sid; |
| |
| if (!set_fscontext) |
| newsbsec->sid = sid; |
| if (!set_rootcontext) { |
| struct inode *newinode = newsb->s_root->d_inode; |
| struct inode_security_struct *newisec = newinode->i_security; |
| newisec->sid = sid; |
| } |
| newsbsec->mntpoint_sid = sid; |
| } |
| if (set_rootcontext) { |
| const struct inode *oldinode = oldsb->s_root->d_inode; |
| const struct inode_security_struct *oldisec = oldinode->i_security; |
| struct inode *newinode = newsb->s_root->d_inode; |
| struct inode_security_struct *newisec = newinode->i_security; |
| |
| newisec->sid = oldisec->sid; |
| } |
| |
| sb_finish_set_opts(newsb); |
| mutex_unlock(&newsbsec->lock); |
| } |
| |
| static int selinux_parse_opts_str(char *options, |
| struct security_mnt_opts *opts) |
| { |
| char *p; |
| char *context = NULL, *defcontext = NULL; |
| char *fscontext = NULL, *rootcontext = NULL; |
| int rc, num_mnt_opts = 0; |
| |
| opts->num_mnt_opts = 0; |
| |
| /* Standard string-based options. */ |
| while ((p = strsep(&options, "|")) != NULL) { |
| int token; |
| substring_t args[MAX_OPT_ARGS]; |
| |
| if (!*p) |
| continue; |
| |
| token = match_token(p, tokens, args); |
| |
| switch (token) { |
| case Opt_context: |
| if (context || defcontext) { |
| rc = -EINVAL; |
| printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); |
| goto out_err; |
| } |
| context = match_strdup(&args[0]); |
| if (!context) { |
| rc = -ENOMEM; |
| goto out_err; |
| } |
| break; |
| |
| case Opt_fscontext: |
| if (fscontext) { |
| rc = -EINVAL; |
| printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); |
| goto out_err; |
| } |
| fscontext = match_strdup(&args[0]); |
| if (!fscontext) { |
| rc = -ENOMEM; |
| goto out_err; |
| } |
| break; |
| |
| case Opt_rootcontext: |
| if (rootcontext) { |
| rc = -EINVAL; |
| printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); |
| goto out_err; |
| } |
| rootcontext = match_strdup(&args[0]); |
| if (!rootcontext) { |
| rc = -ENOMEM; |
| goto out_err; |
| } |
| break; |
| |
| case Opt_defcontext: |
| if (context || defcontext) { |
| rc = -EINVAL; |
| printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); |
| goto out_err; |
| } |
| defcontext = match_strdup(&args[0]); |
| if (!defcontext) { |
| rc = -ENOMEM; |
| goto out_err; |
| } |
| break; |
| case Opt_labelsupport: |
| break; |
| default: |
| rc = -EINVAL; |
| printk(KERN_WARNING "SELinux: unknown mount option\n"); |
| goto out_err; |
| |
| } |
| } |
| |
| rc = -ENOMEM; |
| opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); |
| if (!opts->mnt_opts) |
| goto out_err; |
| |
| opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); |
| if (!opts->mnt_opts_flags) { |
| kfree(opts->mnt_opts); |
| goto out_err; |
| } |
| |
| if (fscontext) { |
| opts->mnt_opts[num_mnt_opts] = fscontext; |
| opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; |
| } |
| if (context) { |
| opts->mnt_opts[num_mnt_opts] = context; |
| opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; |
| } |
| if (rootcontext) { |
| opts->mnt_opts[num_mnt_opts] = rootcontext; |
| opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; |
| } |
| if (defcontext) { |
| opts->mnt_opts[num_mnt_opts] = defcontext; |
| opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; |
| } |
| |
| opts->num_mnt_opts = num_mnt_opts; |
| return 0; |
| |
| out_err: |
| kfree(context); |
| kfree(defcontext); |
| kfree(fscontext); |
| kfree(rootcontext); |
| return rc; |
| } |
| /* |
| * string mount options parsing and call set the sbsec |
| */ |
| static int superblock_doinit(struct super_block *sb, void *data) |
| { |
| int rc = 0; |
| char *options = data; |
| struct security_mnt_opts opts; |
| |
| security_init_mnt_opts(&opts); |
| |
| if (!data) |
| goto out; |
| |
| BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); |
| |
| rc = selinux_parse_opts_str(options, &opts); |
| if (rc) |
| goto out_err; |
| |
| out: |
| rc = selinux_set_mnt_opts(sb, &opts); |
| |
| out_err: |
| security_free_mnt_opts(&opts); |
| return rc; |
| } |
| |
| static void selinux_write_opts(struct seq_file *m, |
| struct security_mnt_opts *opts) |
| { |
| int i; |
| char *prefix; |
| |
| for (i = 0; i < opts->num_mnt_opts; i++) { |
| char *has_comma; |
| |
| if (opts->mnt_opts[i]) |
| has_comma = strchr(opts->mnt_opts[i], ','); |
| else |
| has_comma = NULL; |
| |
| switch (opts->mnt_opts_flags[i]) { |
| case CONTEXT_MNT: |
| prefix = CONTEXT_STR; |
| break; |
| case FSCONTEXT_MNT: |
| prefix = FSCONTEXT_STR; |
| break; |
| case ROOTCONTEXT_MNT: |
| prefix = ROOTCONTEXT_STR; |
| break; |
| case DEFCONTEXT_MNT: |
| prefix = DEFCONTEXT_STR; |
| break; |
| case SE_SBLABELSUPP: |
| seq_putc(m, ','); |
| seq_puts(m, LABELSUPP_STR); |
| continue; |
| default: |
| BUG(); |
| }; |
| /* we need a comma before each option */ |
| seq_putc(m, ','); |
| seq_puts(m, prefix); |
| if (has_comma) |
| seq_putc(m, '\"'); |
| seq_puts(m, opts->mnt_opts[i]); |
| if (has_comma) |
| seq_putc(m, '\"'); |
| } |
| } |
| |
| static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) |
| { |
| struct security_mnt_opts opts; |
| int rc; |
| |
| rc = selinux_get_mnt_opts(sb, &opts); |
| if (rc) { |
| /* before policy load we may get EINVAL, don't show anything */ |
| if (rc == -EINVAL) |
| rc = 0; |
| return rc; |
| } |
| |
| selinux_write_opts(m, &opts); |
| |
| security_free_mnt_opts(&opts); |
| |
| return rc; |
| } |
| |
| static inline u16 inode_mode_to_security_class(umode_t mode) |
| { |
| switch (mode & S_IFMT) { |
| case S_IFSOCK: |
| return SECCLASS_SOCK_FILE; |
| case S_IFLNK: |
| return SECCLASS_LNK_FILE; |
| case S_IFREG: |
| return SECCLASS_FILE; |
| case S_IFBLK: |
| return SECCLASS_BLK_FILE; |
| case S_IFDIR: |
| return SECCLASS_DIR; |
| case S_IFCHR: |
| return SECCLASS_CHR_FILE; |
| case S_IFIFO: |
| return SECCLASS_FIFO_FILE; |
| |
| } |
| |
| return SECCLASS_FILE; |
| } |
| |
| static inline int default_protocol_stream(int protocol) |
| { |
| return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); |
| } |
| |
| static inline int default_protocol_dgram(int protocol) |
| { |
| return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); |
| } |
| |
| static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
| { |
| switch (family) { |
| case PF_UNIX: |
| switch (type) { |
| case SOCK_STREAM: |
| case SOCK_SEQPACKET: |
| return SECCLASS_UNIX_STREAM_SOCKET; |
| case SOCK_DGRAM: |
| return SECCLASS_UNIX_DGRAM_SOCKET; |
| } |
| break; |
| case PF_INET: |
| case PF_INET6: |
| switch (type) { |
| case SOCK_STREAM: |
| if (default_protocol_stream(protocol)) |
| return SECCLASS_TCP_SOCKET; |
| else |
| return SECCLASS_RAWIP_SOCKET; |
| case SOCK_DGRAM: |
| if (default_protocol_dgram(protocol)) |
| return SECCLASS_UDP_SOCKET; |
| else |
| return SECCLASS_RAWIP_SOCKET; |
| case SOCK_DCCP: |
| return SECCLASS_DCCP_SOCKET; |
| default: |
| return SECCLASS_RAWIP_SOCKET; |
| } |
| break; |
| case PF_NETLINK: |
| switch (protocol) { |
| case NETLINK_ROUTE: |
| return SECCLASS_NETLINK_ROUTE_SOCKET; |
| case NETLINK_FIREWALL: |
| return SECCLASS_NETLINK_FIREWALL_SOCKET; |
| case NETLINK_INET_DIAG: |
| return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
| case NETLINK_NFLOG: |
| return SECCLASS_NETLINK_NFLOG_SOCKET; |
| case NETLINK_XFRM: |
| return SECCLASS_NETLINK_XFRM_SOCKET; |
| case NETLINK_SELINUX: |
| return SECCLASS_NETLINK_SELINUX_SOCKET; |
| case NETLINK_AUDIT: |
| return SECCLASS_NETLINK_AUDIT_SOCKET; |
| case NETLINK_IP6_FW: |
| return SECCLASS_NETLINK_IP6FW_SOCKET; |
| case NETLINK_DNRTMSG: |
| return SECCLASS_NETLINK_DNRT_SOCKET; |
| case NETLINK_KOBJECT_UEVENT: |
| return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; |
| default: |
| return SECCLASS_NETLINK_SOCKET; |
| } |
| case PF_PACKET: |
| return SECCLASS_PACKET_SOCKET; |
| case PF_KEY: |
| return SECCLASS_KEY_SOCKET; |
| case PF_APPLETALK: |
| return SECCLASS_APPLETALK_SOCKET; |
| } |
| |
| return SECCLASS_SOCKET; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| static int selinux_proc_get_sid(struct proc_dir_entry *de, |
| u16 tclass, |
| u32 *sid) |
| { |
| int buflen, rc; |
| char *buffer, *path, *end; |
| |
| buffer = (char *)__get_free_page(GFP_KERNEL); |
| if (!buffer) |
| return -ENOMEM; |
| |
| buflen = PAGE_SIZE; |
| end = buffer+buflen; |
| *--end = '\0'; |
| buflen--; |
| path = end-1; |
| *path = '/'; |
| while (de && de != de->parent) { |
| buflen -= de->namelen + 1; |
| if (buflen < 0) |
| break; |
| end -= de->namelen; |
| memcpy(end, de->name, de->namelen); |
| *--end = '/'; |
| path = end; |
| de = de->parent; |
| } |
| rc = security_genfs_sid("proc", path, tclass, sid); |
| free_page((unsigned long)buffer); |
| return rc; |
| } |
| #else |
| static int selinux_proc_get_sid(struct proc_dir_entry *de, |
| u16 tclass, |
| u32 *sid) |
| { |
| return -EINVAL; |
| } |
| #endif |
| |
| /* The inode's security attributes must be initialized before first use. */ |
| static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) |
| { |
| struct superblock_security_struct *sbsec = NULL; |
| struct inode_security_struct *isec = inode->i_security; |
| u32 sid; |
| struct dentry *dentry; |
| #define INITCONTEXTLEN 255 |
| char *context = NULL; |
| unsigned len = 0; |
| int rc = 0; |
| |
| if (isec->initialized) |
| goto out; |
| |
| mutex_lock(&isec->lock); |
| if (isec->initialized) |
| goto out_unlock; |
| |
| sbsec = inode->i_sb->s_security; |
| if (!(sbsec->flags & SE_SBINITIALIZED)) { |
| /* Defer initialization until selinux_complete_init, |
| after the initial policy is loaded and the security |
| server is ready to handle calls. */ |
| spin_lock(&sbsec->isec_lock); |
| if (list_empty(&isec->list)) |
| list_add(&isec->list, &sbsec->isec_head); |
| spin_unlock(&sbsec->isec_lock); |
| goto out_unlock; |
| } |
| |
| switch (sbsec->behavior) { |
| case SECURITY_FS_USE_XATTR: |
| if (!inode->i_op->getxattr) { |
| isec->sid = sbsec->def_sid; |
| break; |
| } |
| |
| /* Need a dentry, since the xattr API requires one. |
| Life would be simpler if we could just pass the inode. */ |
| if (opt_dentry) { |
| /* Called from d_instantiate or d_splice_alias. */ |
| dentry = dget(opt_dentry); |
| } else { |
| /* Called from selinux_complete_init, try to find a dentry. */ |
| dentry = d_find_alias(inode); |
| } |
| if (!dentry) { |
| /* |
| * this is can be hit on boot when a file is accessed |
| * before the policy is loaded. When we load policy we |
| * may find inodes that have no dentry on the |
| * sbsec->isec_head list. No reason to complain as these |
| * will get fixed up the next time we go through |
| * inode_doinit with a dentry, before these inodes could |
| * be used again by userspace. |
| */ |
| goto out_unlock; |
| } |
| |
| len = INITCONTEXTLEN; |
| context = kmalloc(len+1, GFP_NOFS); |
| if (!context) { |
| rc = -ENOMEM; |
| dput(dentry); |
| goto out_unlock; |
| } |
| context[len] = '\0'; |
| rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, |
| context, len); |
| if (rc == -ERANGE) { |
| kfree(context); |
| |
| /* Need a larger buffer. Query for the right size. */ |
| rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, |
| NULL, 0); |
| if (rc < 0) { |
| dput(dentry); |
| goto out_unlock; |
| } |
| len = rc; |
| context = kmalloc(len+1, GFP_NOFS); |
| if (!context) { |
| rc = -ENOMEM; |
| dput(dentry); |
| goto out_unlock; |
| } |
| context[len] = '\0'; |
| rc = inode->i_op->getxattr(dentry, |
| XATTR_NAME_SELINUX, |
| context, len); |
| } |
| dput(dentry); |
| if (rc < 0) { |
| if (rc != -ENODATA) { |
| printk(KERN_WARNING "SELinux: %s: getxattr returned " |
| "%d for dev=%s ino=%ld\n", __func__, |
| -rc, inode->i_sb->s_id, inode->i_ino); |
| kfree(context); |
| goto out_unlock; |
| } |
| /* Map ENODATA to the default file SID */ |
| sid = sbsec->def_sid; |
| rc = 0; |
| } else { |
| rc = security_context_to_sid_default(context, rc, &sid, |
| sbsec->def_sid, |
| GFP_NOFS); |
| if (rc) { |
| char *dev = inode->i_sb->s_id; |
| unsigned long ino = inode->i_ino; |
| |
| if (rc == -EINVAL) { |
| if (printk_ratelimit()) |
| printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " |
| "context=%s. This indicates you may need to relabel the inode or the " |
| "filesystem in question.\n", ino, dev, context); |
| } else { |
| printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " |
| "returned %d for dev=%s ino=%ld\n", |
| __func__, context, -rc, dev, ino); |
| } |
| kfree(context); |
| /* Leave with the unlabeled SID */ |
| rc = 0; |
| break; |
| } |
| } |
| kfree(context); |
| isec->sid = sid; |
| break; |
| case SECURITY_FS_USE_TASK: |
| isec->sid = isec->task_sid; |
| break; |
| case SECURITY_FS_USE_TRANS: |
| /* Default to the fs SID. */ |
| isec->sid = sbsec->sid; |
| |
| /* Try to obtain a transition SID. */ |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| rc = security_transition_sid(isec->task_sid, |
| sbsec->sid, |
| isec->sclass, |
| &sid); |
| if (rc) |
| goto out_unlock; |
| isec->sid = sid; |
| break; |
| case SECURITY_FS_USE_MNTPOINT: |
| isec->sid = sbsec->mntpoint_sid; |
| break; |
| default: |
| /* Default to the fs superblock SID. */ |
| isec->sid = sbsec->sid; |
| |
| if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { |
| struct proc_inode *proci = PROC_I(inode); |
| if (proci->pde) { |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| rc = selinux_proc_get_sid(proci->pde, |
| isec->sclass, |
| &sid); |
| if (rc) |
| goto out_unlock; |
| isec->sid = sid; |
| } |
| } |
| break; |
| } |
| |
| isec->initialized = 1; |
| |
| out_unlock: |
| mutex_unlock(&isec->lock); |
| out: |
| if (isec->sclass == SECCLASS_FILE) |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| return rc; |
| } |
| |
| /* Convert a Linux signal to an access vector. */ |
| static inline u32 signal_to_av(int sig) |
| { |
| u32 perm = 0; |
| |
| switch (sig) { |
| case SIGCHLD: |
| /* Commonly granted from child to parent. */ |
| perm = PROCESS__SIGCHLD; |
| break; |
| case SIGKILL: |
| /* Cannot be caught or ignored */ |
| perm = PROCESS__SIGKILL; |
| break; |
| case SIGSTOP: |
| /* Cannot be caught or ignored */ |
| perm = PROCESS__SIGSTOP; |
| break; |
| default: |
| /* All other signals. */ |
| perm = PROCESS__SIGNAL; |
| break; |
| } |
| |
| return perm; |
| } |
| |
| /* |
| * Check permission between a pair of credentials |
| * fork check, ptrace check, etc. |
| */ |
| static int cred_has_perm(const struct cred *actor, |
| const struct cred *target, |
| u32 perms) |
| { |
| u32 asid = cred_sid(actor), tsid = cred_sid(target); |
| |
| return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); |
| } |
| |
| /* |
| * Check permission between a pair of tasks, e.g. signal checks, |
| * fork check, ptrace check, etc. |
| * tsk1 is the actor and tsk2 is the target |
| * - this uses the default subjective creds of tsk1 |
| */ |
| static int task_has_perm(const struct task_struct *tsk1, |
| const struct task_struct *tsk2, |
| u32 perms) |
| { |
| const struct task_security_struct *__tsec1, *__tsec2; |
| u32 sid1, sid2; |
| |
| rcu_read_lock(); |
| __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; |
| __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; |
| rcu_read_unlock(); |
| return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); |
| } |
| |
| /* |
| * Check permission between current and another task, e.g. signal checks, |
| * fork check, ptrace check, etc. |
| * current is the actor and tsk2 is the target |
| * - this uses current's subjective creds |
| */ |
| static int current_has_perm(const struct task_struct *tsk, |
| u32 perms) |
| { |
| u32 sid, tsid; |
| |
| sid = current_sid(); |
| tsid = task_sid(tsk); |
| return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); |
| } |
| |
| #if CAP_LAST_CAP > 63 |
| #error Fix SELinux to handle capabilities > 63. |
| #endif |
| |
| /* Check whether a task is allowed to use a capability. */ |
| static int task_has_capability(struct task_struct *tsk, |
| const struct cred *cred, |
| int cap, int audit) |
| { |
| struct common_audit_data ad; |
| struct av_decision avd; |
| u16 sclass; |
| u32 sid = cred_sid(cred); |
| u32 av = CAP_TO_MASK(cap); |
| int rc; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, CAP); |
| ad.tsk = tsk; |
| ad.u.cap = cap; |
| |
| switch (CAP_TO_INDEX(cap)) { |
| case 0: |
| sclass = SECCLASS_CAPABILITY; |
| break; |
| case 1: |
| sclass = SECCLASS_CAPABILITY2; |
| break; |
| default: |
| printk(KERN_ERR |
| "SELinux: out of range capability %d\n", cap); |
| BUG(); |
| } |
| |
| rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
| if (audit == SECURITY_CAP_AUDIT) |
| avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
| return rc; |
| } |
| |
| /* Check whether a task is allowed to use a system operation. */ |
| static int task_has_system(struct task_struct *tsk, |
| u32 perms) |
| { |
| u32 sid = task_sid(tsk); |
| |
| return avc_has_perm(sid, SECINITSID_KERNEL, |
| SECCLASS_SYSTEM, perms, NULL); |
| } |
| |
| /* Check whether a task has a particular permission to an inode. |
| The 'adp' parameter is optional and allows other audit |
| data to be passed (e.g. the dentry). */ |
| static int inode_has_perm(const struct cred *cred, |
| struct inode *inode, |
| u32 perms, |
| struct common_audit_data *adp) |
| { |
| struct inode_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid; |
| |
| validate_creds(cred); |
| |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| |
| sid = cred_sid(cred); |
| isec = inode->i_security; |
| |
| if (!adp) { |
| adp = &ad; |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.inode = inode; |
| } |
| |
| return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
| } |
| |
| /* Same as inode_has_perm, but pass explicit audit data containing |
| the dentry to help the auditing code to more easily generate the |
| pathname if needed. */ |
| static inline int dentry_has_perm(const struct cred *cred, |
| struct vfsmount *mnt, |
| struct dentry *dentry, |
| u32 av) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct common_audit_data ad; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path.mnt = mnt; |
| ad.u.fs.path.dentry = dentry; |
| return inode_has_perm(cred, inode, av, &ad); |
| } |
| |
| /* Check whether a task can use an open file descriptor to |
| access an inode in a given way. Check access to the |
| descriptor itself, and then use dentry_has_perm to |
| check a particular permission to the file. |
| Access to the descriptor is implicitly granted if it |
| has the same SID as the process. If av is zero, then |
| access to the file is not checked, e.g. for cases |
| where only the descriptor is affected like seek. */ |
| static int file_has_perm(const struct cred *cred, |
| struct file *file, |
| u32 av) |
| { |
| struct file_security_struct *fsec = file->f_security; |
| struct inode *inode = file->f_path.dentry->d_inode; |
| struct common_audit_data ad; |
| u32 sid = cred_sid(cred); |
| int rc; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path = file->f_path; |
| |
| if (sid != fsec->sid) { |
| rc = avc_has_perm(sid, fsec->sid, |
| SECCLASS_FD, |
| FD__USE, |
| &ad); |
| if (rc) |
| goto out; |
| } |
| |
| /* av is zero if only checking access to the descriptor. */ |
| rc = 0; |
| if (av) |
| rc = inode_has_perm(cred, inode, av, &ad); |
| |
| out: |
| return rc; |
| } |
| |
| /* Check whether a task can create a file. */ |
| static int may_create(struct inode *dir, |
| struct dentry *dentry, |
| u16 tclass) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| struct inode_security_struct *dsec; |
| struct superblock_security_struct *sbsec; |
| u32 sid, newsid; |
| struct common_audit_data ad; |
| int rc; |
| |
| dsec = dir->i_security; |
| sbsec = dir->i_sb->s_security; |
| |
| sid = tsec->sid; |
| newsid = tsec->create_sid; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path.dentry = dentry; |
| |
| rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
| DIR__ADD_NAME | DIR__SEARCH, |
| &ad); |
| if (rc) |
| return rc; |
| |
| if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { |
| rc = security_transition_sid(sid, dsec->sid, tclass, &newsid); |
| if (rc) |
| return rc; |
| } |
| |
| rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
| if (rc) |
| return rc; |
| |
| return avc_has_perm(newsid, sbsec->sid, |
| SECCLASS_FILESYSTEM, |
| FILESYSTEM__ASSOCIATE, &ad); |
| } |
| |
| /* Check whether a task can create a key. */ |
| static int may_create_key(u32 ksid, |
| struct task_struct *ctx) |
| { |
| u32 sid = task_sid(ctx); |
| |
| return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
| } |
| |
| #define MAY_LINK 0 |
| #define MAY_UNLINK 1 |
| #define MAY_RMDIR 2 |
| |
| /* Check whether a task can link, unlink, or rmdir a file/directory. */ |
| static int may_link(struct inode *dir, |
| struct dentry *dentry, |
| int kind) |
| |
| { |
| struct inode_security_struct *dsec, *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| u32 av; |
| int rc; |
| |
| dsec = dir->i_security; |
| isec = dentry->d_inode->i_security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path.dentry = dentry; |
| |
| av = DIR__SEARCH; |
| av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); |
| rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
| if (rc) |
| return rc; |
| |
| switch (kind) { |
| case MAY_LINK: |
| av = FILE__LINK; |
| break; |
| case MAY_UNLINK: |
| av = FILE__UNLINK; |
| break; |
| case MAY_RMDIR: |
| av = DIR__RMDIR; |
| break; |
| default: |
| printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
| __func__, kind); |
| return 0; |
| } |
| |
| rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
| return rc; |
| } |
| |
| static inline int may_rename(struct inode *old_dir, |
| struct dentry *old_dentry, |
| struct inode *new_dir, |
| struct dentry *new_dentry) |
| { |
| struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| u32 av; |
| int old_is_dir, new_is_dir; |
| int rc; |
| |
| old_dsec = old_dir->i_security; |
| old_isec = old_dentry->d_inode->i_security; |
| old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); |
| new_dsec = new_dir->i_security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| |
| ad.u.fs.path.dentry = old_dentry; |
| rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
| DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
| if (rc) |
| return rc; |
| rc = avc_has_perm(sid, old_isec->sid, |
| old_isec->sclass, FILE__RENAME, &ad); |
| if (rc) |
| return rc; |
| if (old_is_dir && new_dir != old_dir) { |
| rc = avc_has_perm(sid, old_isec->sid, |
| old_isec->sclass, DIR__REPARENT, &ad); |
| if (rc) |
| return rc; |
| } |
| |
| ad.u.fs.path.dentry = new_dentry; |
| av = DIR__ADD_NAME | DIR__SEARCH; |
| if (new_dentry->d_inode) |
| av |= DIR__REMOVE_NAME; |
| rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
| if (rc) |
| return rc; |
| if (new_dentry->d_inode) { |
| new_isec = new_dentry->d_inode->i_security; |
| new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); |
| rc = avc_has_perm(sid, new_isec->sid, |
| new_isec->sclass, |
| (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); |
| if (rc) |
| return rc; |
| } |
| |
| return 0; |
| } |
| |
| /* Check whether a task can perform a filesystem operation. */ |
| static int superblock_has_perm(const struct cred *cred, |
| struct super_block *sb, |
| u32 perms, |
| struct common_audit_data *ad) |
| { |
| struct superblock_security_struct *sbsec; |
| u32 sid = cred_sid(cred); |
| |
| sbsec = sb->s_security; |
| return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
| } |
| |
| /* Convert a Linux mode and permission mask to an access vector. */ |
| static inline u32 file_mask_to_av(int mode, int mask) |
| { |
| u32 av = 0; |
| |
| if ((mode & S_IFMT) != S_IFDIR) { |
| if (mask & MAY_EXEC) |
| av |= FILE__EXECUTE; |
| if (mask & MAY_READ) |
| av |= FILE__READ; |
| |
| if (mask & MAY_APPEND) |
| av |= FILE__APPEND; |
| else if (mask & MAY_WRITE) |
| av |= FILE__WRITE; |
| |
| } else { |
| if (mask & MAY_EXEC) |
| av |= DIR__SEARCH; |
| if (mask & MAY_WRITE) |
| av |= DIR__WRITE; |
| if (mask & MAY_READ) |
| av |= DIR__READ; |
| } |
| |
| return av; |
| } |
| |
| /* Convert a Linux file to an access vector. */ |
| static inline u32 file_to_av(struct file *file) |
| { |
| u32 av = 0; |
| |
| if (file->f_mode & FMODE_READ) |
| av |= FILE__READ; |
| if (file->f_mode & FMODE_WRITE) { |
| if (file->f_flags & O_APPEND) |
| av |= FILE__APPEND; |
| else |
| av |= FILE__WRITE; |
| } |
| if (!av) { |
| /* |
| * Special file opened with flags 3 for ioctl-only use. |
| */ |
| av = FILE__IOCTL; |
| } |
| |
| return av; |
| } |
| |
| /* |
| * Convert a file to an access vector and include the correct open |
| * open permission. |
| */ |
| static inline u32 open_file_to_av(struct file *file) |
| { |
| u32 av = file_to_av(file); |
| |
| if (selinux_policycap_openperm) |
| av |= FILE__OPEN; |
| |
| return av; |
| } |
| |
| /* Hook functions begin here. */ |
| |
| static int selinux_ptrace_access_check(struct task_struct *child, |
| unsigned int mode) |
| { |
| int rc; |
| |
| rc = cap_ptrace_access_check(child, mode); |
| if (rc) |
| return rc; |
| |
| if (mode == PTRACE_MODE_READ) { |
| u32 sid = current_sid(); |
| u32 csid = task_sid(child); |
| return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); |
| } |
| |
| return current_has_perm(child, PROCESS__PTRACE); |
| } |
| |
| static int selinux_ptrace_traceme(struct task_struct *parent) |
| { |
| int rc; |
| |
| rc = cap_ptrace_traceme(parent); |
| if (rc) |
| return rc; |
| |
| return task_has_perm(parent, current, PROCESS__PTRACE); |
| } |
| |
| static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, |
| kernel_cap_t *inheritable, kernel_cap_t *permitted) |
| { |
| int error; |
| |
| error = current_has_perm(target, PROCESS__GETCAP); |
| if (error) |
| return error; |
| |
| return cap_capget(target, effective, inheritable, permitted); |
| } |
| |
| static int selinux_capset(struct cred *new, const struct cred *old, |
| const kernel_cap_t *effective, |
| const kernel_cap_t *inheritable, |
| const kernel_cap_t *permitted) |
| { |
| int error; |
| |
| error = cap_capset(new, old, |
| effective, inheritable, permitted); |
| if (error) |
| return error; |
| |
| return cred_has_perm(old, new, PROCESS__SETCAP); |
| } |
| |
| /* |
| * (This comment used to live with the selinux_task_setuid hook, |
| * which was removed). |
| * |
| * Since setuid only affects the current process, and since the SELinux |
| * controls are not based on the Linux identity attributes, SELinux does not |
| * need to control this operation. However, SELinux does control the use of |
| * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. |
| */ |
| |
| static int selinux_capable(struct task_struct *tsk, const struct cred *cred, |
| int cap, int audit) |
| { |
| int rc; |
| |
| rc = cap_capable(tsk, cred, cap, audit); |
| if (rc) |
| return rc; |
| |
| return task_has_capability(tsk, cred, cap, audit); |
| } |
| |
| static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) |
| { |
| int buflen, rc; |
| char *buffer, *path, *end; |
| |
| rc = -ENOMEM; |
| buffer = (char *)__get_free_page(GFP_KERNEL); |
| if (!buffer) |
| goto out; |
| |
| buflen = PAGE_SIZE; |
| end = buffer+buflen; |
| *--end = '\0'; |
| buflen--; |
| path = end-1; |
| *path = '/'; |
| while (table) { |
| const char *name = table->procname; |
| size_t namelen = strlen(name); |
| buflen -= namelen + 1; |
| if (buflen < 0) |
| goto out_free; |
| end -= namelen; |
| memcpy(end, name, namelen); |
| *--end = '/'; |
| path = end; |
| table = table->parent; |
| } |
| buflen -= 4; |
| if (buflen < 0) |
| goto out_free; |
| end -= 4; |
| memcpy(end, "/sys", 4); |
| path = end; |
| rc = security_genfs_sid("proc", path, tclass, sid); |
| out_free: |
| free_page((unsigned long)buffer); |
| out: |
| return rc; |
| } |
| |
| static int selinux_sysctl(ctl_table *table, int op) |
| { |
| int error = 0; |
| u32 av; |
| u32 tsid, sid; |
| int rc; |
| |
| sid = current_sid(); |
| |
| rc = selinux_sysctl_get_sid(table, (op == 0001) ? |
| SECCLASS_DIR : SECCLASS_FILE, &tsid); |
| if (rc) { |
| /* Default to the well-defined sysctl SID. */ |
| tsid = SECINITSID_SYSCTL; |
| } |
| |
| /* The op values are "defined" in sysctl.c, thereby creating |
| * a bad coupling between this module and sysctl.c */ |
| if (op == 001) { |
| error = avc_has_perm(sid, tsid, |
| SECCLASS_DIR, DIR__SEARCH, NULL); |
| } else { |
| av = 0; |
| if (op & 004) |
| av |= FILE__READ; |
| if (op & 002) |
| av |= FILE__WRITE; |
| if (av) |
| error = avc_has_perm(sid, tsid, |
| SECCLASS_FILE, av, NULL); |
| } |
| |
| return error; |
| } |
| |
| static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
| { |
| const struct cred *cred = current_cred(); |
| int rc = 0; |
| |
| if (!sb) |
| return 0; |
| |
| switch (cmds) { |
| case Q_SYNC: |
| case Q_QUOTAON: |
| case Q_QUOTAOFF: |
| case Q_SETINFO: |
| case Q_SETQUOTA: |
| rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
| break; |
| case Q_GETFMT: |
| case Q_GETINFO: |
| case Q_GETQUOTA: |
| rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
| break; |
| default: |
| rc = 0; /* let the kernel handle invalid cmds */ |
| break; |
| } |
| return rc; |
| } |
| |
| static int selinux_quota_on(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); |
| } |
| |
| static int selinux_syslog(int type) |
| { |
| int rc; |
| |
| switch (type) { |
| case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
| case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ |
| rc = task_has_system(current, SYSTEM__SYSLOG_READ); |
| break; |
| case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
| case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ |
| /* Set level of messages printed to console */ |
| case SYSLOG_ACTION_CONSOLE_LEVEL: |
| rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); |
| break; |
| case SYSLOG_ACTION_CLOSE: /* Close log */ |
| case SYSLOG_ACTION_OPEN: /* Open log */ |
| case SYSLOG_ACTION_READ: /* Read from log */ |
| case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ |
| case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ |
| default: |
| rc = task_has_system(current, SYSTEM__SYSLOG_MOD); |
| break; |
| } |
| return rc; |
| } |
| |
| /* |
| * Check that a process has enough memory to allocate a new virtual |
| * mapping. 0 means there is enough memory for the allocation to |
| * succeed and -ENOMEM implies there is not. |
| * |
| * Do not audit the selinux permission check, as this is applied to all |
| * processes that allocate mappings. |
| */ |
| static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
| { |
| int rc, cap_sys_admin = 0; |
| |
| rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN, |
| SECURITY_CAP_NOAUDIT); |
| if (rc == 0) |
| cap_sys_admin = 1; |
| |
| return __vm_enough_memory(mm, pages, cap_sys_admin); |
| } |
| |
| /* binprm security operations */ |
| |
| static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
| { |
| const struct task_security_struct *old_tsec; |
| struct task_security_struct *new_tsec; |
| struct inode_security_struct *isec; |
| struct common_audit_data ad; |
| struct inode *inode = bprm->file->f_path.dentry->d_inode; |
| int rc; |
| |
| rc = cap_bprm_set_creds(bprm); |
| if (rc) |
| return rc; |
| |
| /* SELinux context only depends on initial program or script and not |
| * the script interpreter */ |
| if (bprm->cred_prepared) |
| return 0; |
| |
| old_tsec = current_security(); |
| new_tsec = bprm->cred->security; |
| isec = inode->i_security; |
| |
| /* Default to the current task SID. */ |
| new_tsec->sid = old_tsec->sid; |
| new_tsec->osid = old_tsec->sid; |
| |
| /* Reset fs, key, and sock SIDs on execve. */ |
| new_tsec->create_sid = 0; |
| new_tsec->keycreate_sid = 0; |
| new_tsec->sockcreate_sid = 0; |
| |
| if (old_tsec->exec_sid) { |
| new_tsec->sid = old_tsec->exec_sid; |
| /* Reset exec SID on execve. */ |
| new_tsec->exec_sid = 0; |
| } else { |
| /* Check for a default transition on this program. */ |
| rc = security_transition_sid(old_tsec->sid, isec->sid, |
| SECCLASS_PROCESS, &new_tsec->sid); |
| if (rc) |
| return rc; |
| } |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path = bprm->file->f_path; |
| |
| if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) |
| new_tsec->sid = old_tsec->sid; |
| |
| if (new_tsec->sid == old_tsec->sid) { |
| rc = avc_has_perm(old_tsec->sid, isec->sid, |
| SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
| if (rc) |
| return rc; |
| } else { |
| /* Check permissions for the transition. */ |
| rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
| SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(new_tsec->sid, isec->sid, |
| SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
| if (rc) |
| return rc; |
| |
| /* Check for shared state */ |
| if (bprm->unsafe & LSM_UNSAFE_SHARE) { |
| rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
| SECCLASS_PROCESS, PROCESS__SHARE, |
| NULL); |
| if (rc) |
| return -EPERM; |
| } |
| |
| /* Make sure that anyone attempting to ptrace over a task that |
| * changes its SID has the appropriate permit */ |
| if (bprm->unsafe & |
| (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { |
| struct task_struct *tracer; |
| struct task_security_struct *sec; |
| u32 ptsid = 0; |
| |
| rcu_read_lock(); |
| tracer = tracehook_tracer_task(current); |
| if (likely(tracer != NULL)) { |
| sec = __task_cred(tracer)->security; |
| ptsid = sec->sid; |
| } |
| rcu_read_unlock(); |
| |
| if (ptsid != 0) { |
| rc = avc_has_perm(ptsid, new_tsec->sid, |
| SECCLASS_PROCESS, |
| PROCESS__PTRACE, NULL); |
| if (rc) |
| return -EPERM; |
| } |
| } |
| |
| /* Clear any possibly unsafe personality bits on exec: */ |
| bprm->per_clear |= PER_CLEAR_ON_SETID; |
| } |
| |
| return 0; |
| } |
| |
| static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| u32 sid, osid; |
| int atsecure = 0; |
| |
| sid = tsec->sid; |
| osid = tsec->osid; |
| |
| if (osid != sid) { |
| /* Enable secure mode for SIDs transitions unless |
| the noatsecure permission is granted between |
| the two SIDs, i.e. ahp returns 0. */ |
| atsecure = avc_has_perm(osid, sid, |
| SECCLASS_PROCESS, |
| PROCESS__NOATSECURE, NULL); |
| } |
| |
| return (atsecure || cap_bprm_secureexec(bprm)); |
| } |
| |
| extern struct vfsmount *selinuxfs_mount; |
| extern struct dentry *selinux_null; |
| |
| /* Derived from fs/exec.c:flush_old_files. */ |
| static inline void flush_unauthorized_files(const struct cred *cred, |
| struct files_struct *files) |
| { |
| struct common_audit_data ad; |
| struct file *file, *devnull = NULL; |
| struct tty_struct *tty; |
| struct fdtable *fdt; |
| long j = -1; |
| int drop_tty = 0; |
| |
| tty = get_current_tty(); |
| if (tty) { |
| spin_lock(&tty_files_lock); |
| if (!list_empty(&tty->tty_files)) { |
| struct tty_file_private *file_priv; |
| struct inode *inode; |
| |
| /* Revalidate access to controlling tty. |
| Use inode_has_perm on the tty inode directly rather |
| than using file_has_perm, as this particular open |
| file may belong to another process and we are only |
| interested in the inode-based check here. */ |
| file_priv = list_first_entry(&tty->tty_files, |
| struct tty_file_private, list); |
| file = file_priv->file; |
| inode = file->f_path.dentry->d_inode; |
| if (inode_has_perm(cred, inode, |
| FILE__READ | FILE__WRITE, NULL)) { |
| drop_tty = 1; |
| } |
| } |
| spin_unlock(&tty_files_lock); |
| tty_kref_put(tty); |
| } |
| /* Reset controlling tty. */ |
| if (drop_tty) |
| no_tty(); |
| |
| /* Revalidate access to inherited open files. */ |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| |
| spin_lock(&files->file_lock); |
| for (;;) { |
| unsigned long set, i; |
| int fd; |
| |
| j++; |
| i = j * __NFDBITS; |
| fdt = files_fdtable(files); |
| if (i >= fdt->max_fds) |
| break; |
| set = fdt->open_fds->fds_bits[j]; |
| if (!set) |
| continue; |
| spin_unlock(&files->file_lock); |
| for ( ; set ; i++, set >>= 1) { |
| if (set & 1) { |
| file = fget(i); |
| if (!file) |
| continue; |
| if (file_has_perm(cred, |
| file, |
| file_to_av(file))) { |
| sys_close(i); |
| fd = get_unused_fd(); |
| if (fd != i) { |
| if (fd >= 0) |
| put_unused_fd(fd); |
| fput(file); |
| continue; |
| } |
| if (devnull) { |
| get_file(devnull); |
| } else { |
| devnull = dentry_open( |
| dget(selinux_null), |
| mntget(selinuxfs_mount), |
| O_RDWR, cred); |
| if (IS_ERR(devnull)) { |
| devnull = NULL; |
| put_unused_fd(fd); |
| fput(file); |
| continue; |
| } |
| } |
| fd_install(fd, devnull); |
| } |
| fput(file); |
| } |
| } |
| spin_lock(&files->file_lock); |
| |
| } |
| spin_unlock(&files->file_lock); |
| } |
| |
| /* |
| * Prepare a process for imminent new credential changes due to exec |
| */ |
| static void selinux_bprm_committing_creds(struct linux_binprm *bprm) |
| { |
| struct task_security_struct *new_tsec; |
| struct rlimit *rlim, *initrlim; |
| int rc, i; |
| |
| new_tsec = bprm->cred->security; |
| if (new_tsec->sid == new_tsec->osid) |
| return; |
| |
| /* Close files for which the new task SID is not authorized. */ |
| flush_unauthorized_files(bprm->cred, current->files); |
| |
| /* Always clear parent death signal on SID transitions. */ |
| current->pdeath_signal = 0; |
| |
| /* Check whether the new SID can inherit resource limits from the old |
| * SID. If not, reset all soft limits to the lower of the current |
| * task's hard limit and the init task's soft limit. |
| * |
| * Note that the setting of hard limits (even to lower them) can be |
| * controlled by the setrlimit check. The inclusion of the init task's |
| * soft limit into the computation is to avoid resetting soft limits |
| * higher than the default soft limit for cases where the default is |
| * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. |
| */ |
| rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, |
| PROCESS__RLIMITINH, NULL); |
| if (rc) { |
| /* protect against do_prlimit() */ |
| task_lock(current); |
| for (i = 0; i < RLIM_NLIMITS; i++) { |
| rlim = current->signal->rlim + i; |
| initrlim = init_task.signal->rlim + i; |
| rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); |
| } |
| task_unlock(current); |
| update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); |
| } |
| } |
| |
| /* |
| * Clean up the process immediately after the installation of new credentials |
| * due to exec |
| */ |
| static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| struct itimerval itimer; |
| u32 osid, sid; |
| int rc, i; |
| |
| osid = tsec->osid; |
| sid = tsec->sid; |
| |
| if (sid == osid) |
| return; |
| |
| /* Check whether the new SID can inherit signal state from the old SID. |
| * If not, clear itimers to avoid subsequent signal generation and |
| * flush and unblock signals. |
| * |
| * This must occur _after_ the task SID has been updated so that any |
| * kill done after the flush will be checked against the new SID. |
| */ |
| rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); |
| if (rc) { |
| memset(&itimer, 0, sizeof itimer); |
| for (i = 0; i < 3; i++) |
| do_setitimer(i, &itimer, NULL); |
| spin_lock_irq(¤t->sighand->siglock); |
| if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { |
| __flush_signals(current); |
| flush_signal_handlers(current, 1); |
| sigemptyset(¤t->blocked); |
| } |
| spin_unlock_irq(¤t->sighand->siglock); |
| } |
| |
| /* Wake up the parent if it is waiting so that it can recheck |
| * wait permission to the new task SID. */ |
| read_lock(&tasklist_lock); |
| __wake_up_parent(current, current->real_parent); |
| read_unlock(&tasklist_lock); |
| } |
| |
| /* superblock security operations */ |
| |
| static int selinux_sb_alloc_security(struct super_block *sb) |
| { |
| return superblock_alloc_security(sb); |
| } |
| |
| static void selinux_sb_free_security(struct super_block *sb) |
| { |
| superblock_free_security(sb); |
| } |
| |
| static inline int match_prefix(char *prefix, int plen, char *option, int olen) |
| { |
| if (plen > olen) |
| return 0; |
| |
| return !memcmp(prefix, option, plen); |
| } |
| |
| static inline int selinux_option(char *option, int len) |
| { |
| return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
| match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || |
| match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || |
| match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
| match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); |
| } |
| |
| static inline void take_option(char **to, char *from, int *first, int len) |
| { |
| if (!*first) { |
| **to = ','; |
| *to += 1; |
| } else |
| *first = 0; |
| memcpy(*to, from, len); |
| *to += len; |
| } |
| |
| static inline void take_selinux_option(char **to, char *from, int *first, |
| int len) |
| { |
| int current_size = 0; |
| |
| if (!*first) { |
| **to = '|'; |
| *to += 1; |
| } else |
| *first = 0; |
| |
| while (current_size < len) { |
| if (*from != '"') { |
| **to = *from; |
| *to += 1; |
| } |
| from += 1; |
| current_size += 1; |
| } |
| } |
| |
| static int selinux_sb_copy_data(char *orig, char *copy) |
| { |
| int fnosec, fsec, rc = 0; |
| char *in_save, *in_curr, *in_end; |
| char *sec_curr, *nosec_save, *nosec; |
| int open_quote = 0; |
| |
| in_curr = orig; |
| sec_curr = copy; |
| |
| nosec = (char *)get_zeroed_page(GFP_KERNEL); |
| if (!nosec) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| nosec_save = nosec; |
| fnosec = fsec = 1; |
| in_save = in_end = orig; |
| |
| do { |
| if (*in_end == '"') |
| open_quote = !open_quote; |
| if ((*in_end == ',' && open_quote == 0) || |
| *in_end == '\0') { |
| int len = in_end - in_curr; |
| |
| if (selinux_option(in_curr, len)) |
| take_selinux_option(&sec_curr, in_curr, &fsec, len); |
| else |
| take_option(&nosec, in_curr, &fnosec, len); |
| |
| in_curr = in_end + 1; |
| } |
| } while (*in_end++); |
| |
| strcpy(in_save, nosec_save); |
| free_page((unsigned long)nosec_save); |
| out: |
| return rc; |
| } |
| |
| static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
| { |
| const struct cred *cred = current_cred(); |
| struct common_audit_data ad; |
| int rc; |
| |
| rc = superblock_doinit(sb, data); |
| if (rc) |
| return rc; |
| |
| /* Allow all mounts performed by the kernel */ |
| if (flags & MS_KERNMOUNT) |
| return 0; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path.dentry = sb->s_root; |
| return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
| } |
| |
| static int selinux_sb_statfs(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| struct common_audit_data ad; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path.dentry = dentry->d_sb->s_root; |
| return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
| } |
| |
| static int selinux_mount(char *dev_name, |
| struct path *path, |
| char *type, |
| unsigned long flags, |
| void *data) |
| { |
| const struct cred *cred = current_cred(); |
| |
| if (flags & MS_REMOUNT) |
| return superblock_has_perm(cred, path->mnt->mnt_sb, |
| FILESYSTEM__REMOUNT, NULL); |
| else |
| return dentry_has_perm(cred, path->mnt, path->dentry, |
| FILE__MOUNTON); |
| } |
| |
| static int selinux_umount(struct vfsmount *mnt, int flags) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return superblock_has_perm(cred, mnt->mnt_sb, |
| FILESYSTEM__UNMOUNT, NULL); |
| } |
| |
| /* inode security operations */ |
| |
| static int selinux_inode_alloc_security(struct inode *inode) |
| { |
| return inode_alloc_security(inode); |
| } |
| |
| static void selinux_inode_free_security(struct inode *inode) |
| { |
| inode_free_security(inode); |
| } |
| |
| static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
| char **name, void **value, |
| size_t *len) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| struct inode_security_struct *dsec; |
| struct superblock_security_struct *sbsec; |
| u32 sid, newsid, clen; |
| int rc; |
| char *namep = NULL, *context; |
| |
| dsec = dir->i_security; |
| sbsec = dir->i_sb->s_security; |
| |
| sid = tsec->sid; |
| newsid = tsec->create_sid; |
| |
| if ((sbsec->flags & SE_SBINITIALIZED) && |
| (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) |
| newsid = sbsec->mntpoint_sid; |
| else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { |
| rc = security_transition_sid(sid, dsec->sid, |
| inode_mode_to_security_class(inode->i_mode), |
| &newsid); |
| if (rc) { |
| printk(KERN_WARNING "%s: " |
| "security_transition_sid failed, rc=%d (dev=%s " |
| "ino=%ld)\n", |
| __func__, |
| -rc, inode->i_sb->s_id, inode->i_ino); |
| return rc; |
| } |
| } |
| |
| /* Possibly defer initialization to selinux_complete_init. */ |
| if (sbsec->flags & SE_SBINITIALIZED) { |
| struct inode_security_struct *isec = inode->i_security; |
| isec->sclass = inode_mode_to_security_class(inode->i_mode); |
| isec->sid = newsid; |
| isec->initialized = 1; |
| } |
| |
| if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) |
| return -EOPNOTSUPP; |
| |
| if (name) { |
| namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); |
| if (!namep) |
| return -ENOMEM; |
| *name = namep; |
| } |
| |
| if (value && len) { |
| rc = security_sid_to_context_force(newsid, &context, &clen); |
| if (rc) { |
| kfree(namep); |
| return rc; |
| } |
| *value = context; |
| *len = clen; |
| } |
| |
| return 0; |
| } |
| |
| static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) |
| { |
| return may_create(dir, dentry, SECCLASS_FILE); |
| } |
| |
| static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
| { |
| return may_link(dir, old_dentry, MAY_LINK); |
| } |
| |
| static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| return may_link(dir, dentry, MAY_UNLINK); |
| } |
| |
| static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) |
| { |
| return may_create(dir, dentry, SECCLASS_LNK_FILE); |
| } |
| |
| static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) |
| { |
| return may_create(dir, dentry, SECCLASS_DIR); |
| } |
| |
| static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| return may_link(dir, dentry, MAY_RMDIR); |
| } |
| |
| static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) |
| { |
| return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
| } |
| |
| static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
| struct inode *new_inode, struct dentry *new_dentry) |
| { |
| return may_rename(old_inode, old_dentry, new_inode, new_dentry); |
| } |
| |
| static int selinux_inode_readlink(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, NULL, dentry, FILE__READ); |
| } |
| |
| static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, NULL, dentry, FILE__READ); |
| } |
| |
| static int selinux_inode_permission(struct inode *inode, int mask) |
| { |
| const struct cred *cred = current_cred(); |
| struct common_audit_data ad; |
| u32 perms; |
| bool from_access; |
| |
| from_access = mask & MAY_ACCESS; |
| mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
| |
| /* No permission to check. Existence test. */ |
| if (!mask) |
| return 0; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.inode = inode; |
| |
| if (from_access) |
| ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS; |
| |
| perms = file_mask_to_av(inode->i_mode, mask); |
| |
| return inode_has_perm(cred, inode, perms, &ad); |
| } |
| |
| static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) |
| { |
| const struct cred *cred = current_cred(); |
| unsigned int ia_valid = iattr->ia_valid; |
| |
| /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
| if (ia_valid & ATTR_FORCE) { |
| ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | |
| ATTR_FORCE); |
| if (!ia_valid) |
| return 0; |
| } |
| |
| if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
| ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) |
| return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); |
| |
| return dentry_has_perm(cred, NULL, dentry, FILE__WRITE); |
| } |
| |
| static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR); |
| } |
| |
| static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
| { |
| const struct cred *cred = current_cred(); |
| |
| if (!strncmp(name, XATTR_SECURITY_PREFIX, |
| sizeof XATTR_SECURITY_PREFIX - 1)) { |
| if (!strcmp(name, XATTR_NAME_CAPS)) { |
| if (!capable(CAP_SETFCAP)) |
| return -EPERM; |
| } else if (!capable(CAP_SYS_ADMIN)) { |
| /* A different attribute in the security namespace. |
| Restrict to administrator. */ |
| return -EPERM; |
| } |
| } |
| |
| /* Not an attribute we recognize, so just check the |
| ordinary setattr permission. */ |
| return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); |
| } |
| |
| static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct inode_security_struct *isec = inode->i_security; |
| struct superblock_security_struct *sbsec; |
| struct common_audit_data ad; |
| u32 newsid, sid = current_sid(); |
| int rc = 0; |
| |
| if (strcmp(name, XATTR_NAME_SELINUX)) |
| return selinux_inode_setotherxattr(dentry, name); |
| |
| sbsec = inode->i_sb->s_security; |
| if (!(sbsec->flags & SE_SBLABELSUPP)) |
| return -EOPNOTSUPP; |
| |
| if (!is_owner_or_cap(inode)) |
| return -EPERM; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, FS); |
| ad.u.fs.path.dentry = dentry; |
| |
| rc = avc_has_perm(sid, isec->sid, isec->sclass, |
| FILE__RELABELFROM, &ad); |
| if (rc) |
| return rc; |
| |
| rc = security_context_to_sid(value, size, &newsid); |
| if (rc == -EINVAL) { |
| if (!capable(CAP_MAC_ADMIN)) |
| return rc; |
| rc = security_context_to_sid_force(value, size, &newsid); |
| } |
| if (rc) |
| return rc; |
| |
| rc = avc_has_perm(sid, newsid, isec->sclass, |
| FILE__RELABELTO, &ad); |
| if (rc) |
| return rc; |
| |
| rc = security_validate_transition(isec->sid, newsid, sid, |
| isec->sclass); |
| if (rc) |
| return rc; |
| |
| return avc_has_perm(newsid, |
| sbsec->sid, |
| SECCLASS_FILESYSTEM, |
| FILESYSTEM__ASSOCIATE, |
| &ad); |
| } |
| |
| static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
| const void *value, size_t size, |
| int flags) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct inode_security_struct *isec = inode->i_security; |
| u32 newsid; |
| int rc; |
| |
| if (strcmp(name, XATTR_NAME_SELINUX)) { |
| /* Not an attribute we recognize, so nothing to do. */ |
| return; |
| } |
| |
| rc = security_context_to_sid_force(value, size, &newsid); |
| if (rc) { |
| printk(KERN_ERR "SELinux: unable to map context to SID" |
| "for (%s, %lu), rc=%d\n", |
| inode->i_sb->s_id, inode->i_ino, -rc); |
| return; |
| } |
| |
| isec->sid = newsid; |
| return; |
| } |
| |
| static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); |
| } |
| |
| static int selinux_inode_listxattr(struct dentry *dentry) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); |
| } |
| |
| static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
| { |
| if (strcmp(name, XATTR_NAME_SELINUX)) |
| return selinux_inode_setotherxattr(dentry, name); |
| |
| /* No one is allowed to remove a SELinux security label. |
| You can change the label, but all data must be labeled. */ |
| return -EACCES; |
| } |
| |
| /* |
| * Copy the inode security context value to the user. |
| * |
| * Permission check is handled by selinux_inode_getxattr hook. |
| */ |
| static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
| { |
| u32 size; |
| int error; |
| char *context = NULL; |
| struct inode_security_struct *isec = inode->i_security; |
| |
| if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
| return -EOPNOTSUPP; |
| |
| /* |
| * If the caller has CAP_MAC_ADMIN, then get the raw context |
| * value even if it is not defined by current policy; otherwise, |
| * use the in-core value under current policy. |
| * Use the non-auditing forms of the permission checks since |
| * getxattr may be called by unprivileged processes commonly |
| * and lack of permission just means that we fall back to the |
| * in-core context value, not a denial. |
| */ |
| error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN, |
| SECURITY_CAP_NOAUDIT); |
| if (!error) |
| error = security_sid_to_context_force(isec->sid, &context, |
| &size); |
| else |
| error = security_sid_to_context(isec->sid, &context, &size); |
| if (error) |
| return error; |
| error = size; |
| if (alloc) { |
| *buffer = context; |
| goto out_nofree; |
| } |
| kfree(context); |
| out_nofree: |
| return error; |
| } |
| |
| static int selinux_inode_setsecurity(struct inode *inode, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| struct inode_security_struct *isec = inode->i_security; |
| u32 newsid; |
| int rc; |
| |
| if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
| return -EOPNOTSUPP; |
| |
| if (!value || !size) |
| return -EACCES; |
| |
| rc = security_context_to_sid((void *)value, size, &newsid); |
| if (rc) |
| return rc; |
| |
| isec->sid = newsid; |
| isec->initialized = 1; |
| return 0; |
| } |
| |
| static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) |
| { |
| const int len = sizeof(XATTR_NAME_SELINUX); |
| if (buffer && len <= buffer_size) |
| memcpy(buffer, XATTR_NAME_SELINUX, len); |
| return len; |
| } |
| |
| static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) |
| { |
| struct inode_security_struct *isec = inode->i_security; |
| *secid = isec->sid; |
| } |
| |
| /* file security operations */ |
| |
| static int selinux_revalidate_file_permission(struct file *file, int mask) |
| { |
| const struct cred *cred = current_cred(); |
| struct inode *inode = file->f_path.dentry->d_inode; |
| |
| /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
| if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) |
| mask |= MAY_APPEND; |
| |
| return file_has_perm(cred, file, |
| file_mask_to_av(inode->i_mode, mask)); |
| } |
| |
| static int selinux_file_permission(struct file *file, int mask) |
| { |
| struct inode *inode = file->f_path.dentry->d_inode; |
| struct file_security_struct *fsec = file->f_security; |
| struct inode_security_struct *isec = inode->i_security; |
| u32 sid = current_sid(); |
| |
| if (!mask) |
| /* No permission to check. Existence test. */ |
| return 0; |
| |
| if (sid == fsec->sid && fsec->isid == isec->sid && |
| fsec->pseqno == avc_policy_seqno()) |
| /* No change since dentry_open check. */ |
| return 0; |
| |
| return selinux_revalidate_file_permission(file, mask); |
| } |
| |
| static int selinux_file_alloc_security(struct file *file) |
| { |
| return file_alloc_security(file); |
| } |
| |
| static void selinux_file_free_security(struct file *file) |
| { |
| file_free_security(file); |
| } |
| |
| static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| const struct cred *cred = current_cred(); |
| u32 av = 0; |
| |
| if (_IOC_DIR(cmd) & _IOC_WRITE) |
| av |= FILE__WRITE; |
| if (_IOC_DIR(cmd) & _IOC_READ) |
| av |= FILE__READ; |
| if (!av) |
| av = FILE__IOCTL; |
| |
| return file_has_perm(cred, file, av); |
| } |
| |
| static int default_noexec; |
| |
| static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
| { |
| const struct cred *cred = current_cred(); |
| int rc = 0; |
| |
| if (default_noexec && |
| (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { |
| /* |
| * We are making executable an anonymous mapping or a |
| * private file mapping that will also be writable. |
| * This has an additional check. |
| */ |
| rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
| if (rc) |
| goto error; |
| } |
| |
| if (file) { |
| /* read access is always possible with a mapping */ |
| u32 av = FILE__READ; |
| |
| /* write access only matters if the mapping is shared */ |
| if (shared && (prot & PROT_WRITE)) |
| av |= FILE__WRITE; |
| |
| if (prot & PROT_EXEC) |
| av |= FILE__EXECUTE; |
| |
| return file_has_perm(cred, file, av); |
| } |
| |
| error: |
| return rc; |
| } |
| |
| static int selinux_file_mmap(struct file *file, unsigned long reqprot, |
| unsigned long prot, unsigned long flags, |
| unsigned long addr, unsigned long addr_only) |
| { |
| int rc = 0; |
| u32 sid = current_sid(); |
| |
| /* |
| * notice that we are intentionally putting the SELinux check before |
| * the secondary cap_file_mmap check. This is such a likely attempt |
| * at bad behaviour/exploit that we always want to get the AVC, even |
| * if DAC would have also denied the operation. |
| */ |
| if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
| rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
| MEMPROTECT__MMAP_ZERO, NULL); |
| if (rc) |
| return rc; |
| } |
| |
| /* do DAC check on address space usage */ |
| rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); |
| if (rc || addr_only) |
| return rc; |
| |
| if (selinux_checkreqprot) |
| prot = reqprot; |
| |
| return file_map_prot_check(file, prot, |
| (flags & MAP_TYPE) == MAP_SHARED); |
| } |
| |
| static int selinux_file_mprotect(struct vm_area_struct *vma, |
| unsigned long reqprot, |
| unsigned long prot) |
| { |
| const struct cred *cred = current_cred(); |
| |
| if (selinux_checkreqprot) |
| prot = reqprot; |
| |
| if (default_noexec && |
| (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
| int rc = 0; |
| if (vma->vm_start >= vma->vm_mm->start_brk && |
| vma->vm_end <= vma->vm_mm->brk) { |
| rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
| } else if (!vma->vm_file && |
| vma->vm_start <= vma->vm_mm->start_stack && |
| vma->vm_end >= vma->vm_mm->start_stack) { |
| rc = current_has_perm(current, PROCESS__EXECSTACK); |
| } else if (vma->vm_file && vma->anon_vma) { |
| /* |
| * We are making executable a file mapping that has |
| * had some COW done. Since pages might have been |
| * written, check ability to execute the possibly |
| * modified content. This typically should only |
| * occur for text relocations. |
| */ |
| rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
| } |
| if (rc) |
| return rc; |
| } |
| |
| return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); |
| } |
| |
| static int selinux_file_lock(struct file *file, unsigned int cmd) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return file_has_perm(cred, file, FILE__LOCK); |
| } |
| |
| static int selinux_file_fcntl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| const struct cred *cred = current_cred(); |
| int err = 0; |
| |
| switch (cmd) { |
| case F_SETFL: |
| if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { |
| err = -EINVAL; |
| break; |
| } |
| |
| if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { |
| err = file_has_perm(cred, file, FILE__WRITE); |
| break; |
| } |
| /* fall through */ |
| case F_SETOWN: |
| case F_SETSIG: |
| case F_GETFL: |
| case F_GETOWN: |
| case F_GETSIG: |
| /* Just check FD__USE permission */ |
| err = file_has_perm(cred, file, 0); |
| break; |
| case F_GETLK: |
| case F_SETLK: |
| case F_SETLKW: |
| #if BITS_PER_LONG == 32 |
| case F_GETLK64: |
| case F_SETLK64: |
| case F_SETLKW64: |
| #endif |
| if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { |
| err = -EINVAL; |
| break; |
| } |
| err = file_has_perm(cred, file, FILE__LOCK); |
| break; |
| } |
| |
| return err; |
| } |
| |
| static int selinux_file_set_fowner(struct file *file) |
| { |
| struct file_security_struct *fsec; |
| |
| fsec = file->f_security; |
| fsec->fown_sid = current_sid(); |
| |
| return 0; |
| } |
| |
| static int selinux_file_send_sigiotask(struct task_struct *tsk, |
| struct fown_struct *fown, int signum) |
| { |
| struct file *file; |
| u32 sid = task_sid(tsk); |
| u32 perm; |
| struct file_security_struct *fsec; |
| |
| /* struct fown_struct is never outside the context of a struct file */ |
| file = container_of(fown, struct file, f_owner); |
| |
| fsec = file->f_security; |
| |
| if (!signum) |
| perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ |
| else |
| perm = signal_to_av(signum); |
| |
| return avc_has_perm(fsec->fown_sid, sid, |
| SECCLASS_PROCESS, perm, NULL); |
| } |
| |
| static int selinux_file_receive(struct file *file) |
| { |
| const struct cred *cred = current_cred(); |
| |
| return file_has_perm(cred, file, file_to_av(file)); |
| } |
| |
| static int selinux_dentry_open(struct file *file, const struct cred *cred) |
| { |
| struct file_security_struct *fsec; |
| struct inode *inode; |
| struct inode_security_struct *isec; |
| |
| inode = file->f_path.dentry->d_inode; |
| fsec = file->f_security; |
| isec = inode->i_security; |
| /* |
| * Save inode label and policy sequence number |
| * at open-time so that selinux_file_permission |
| * can determine whether revalidation is necessary. |
| * Task label is already saved in the file security |
| * struct as its SID. |
| */ |
| fsec->isid = isec->sid; |
| fsec->pseqno = avc_policy_seqno(); |
| /* |
| * Since the inode label or policy seqno may have changed |
| * between the selinux_inode_permission check and the saving |
| * of state above, recheck that access is still permitted. |
| * Otherwise, access might never be revalidated against the |
| * new inode label or new policy. |
| * This check is not redundant - do not remove. |
| */ |
| return inode_has_perm(cred, inode, open_file_to_av(file), NULL); |
| } |
| |
| /* task security operations */ |
| |
| static int selinux_task_create(unsigned long clone_flags) |
| { |
| return current_has_perm(current, PROCESS__FORK); |
| } |
| |
| /* |
| * allocate the SELinux part of blank credentials |
| */ |
| static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) |
| { |
| struct task_security_struct *tsec; |
| |
| tsec = kzalloc(sizeof(struct task_security_struct), gfp); |
| if (!tsec) |
| return -ENOMEM; |
| |
| cred->security = tsec; |
| return 0; |
| } |
| |
| /* |
| * detach and free the LSM part of a set of credentials |
| */ |
| static void selinux_cred_free(struct cred *cred) |
| { |
| struct task_security_struct *tsec = cred->security; |
| |
| /* |
| * cred->security == NULL if security_cred_alloc_blank() or |
| * security_prepare_creds() returned an error. |
| */ |
| BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); |
| cred->security = (void *) 0x7UL; |
| kfree(tsec); |
| } |
| |
| /* |
| * prepare a new set of credentials for modification |
| */ |
| static int selinux_cred_prepare(struct cred *new, const struct cred *old, |
| gfp_t gfp) |
| { |
| const struct task_security_struct *old_tsec; |
| struct task_security_struct *tsec; |
| |
| old_tsec = old->security; |
| |
| tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); |
| if (!tsec) |
| return -ENOMEM; |
| |
| new->security = tsec; |
| return 0; |
| } |
| |
| /* |
| * transfer the SELinux data to a blank set of creds |
| */ |
| static void selinux_cred_transfer(struct cred *new, const struct cred *old) |
| { |
| const struct task_security_struct *old_tsec = old->security; |
| struct task_security_struct *tsec = new->security; |
| |
| *tsec = *old_tsec; |
| } |
| |
| /* |
| * set the security data for a kernel service |
| * - all the creation contexts are set to unlabelled |
| */ |
| static int selinux_kernel_act_as(struct cred *new, u32 secid) |
| { |
| struct task_security_struct *tsec = new->security; |
| u32 sid = current_sid(); |
| int ret; |
| |
| ret = avc_has_perm(sid, secid, |
| SECCLASS_KERNEL_SERVICE, |
| KERNEL_SERVICE__USE_AS_OVERRIDE, |
| NULL); |
| if (ret == 0) { |
| tsec->sid = secid; |
| tsec->create_sid = 0; |
| tsec->keycreate_sid = 0; |
| tsec->sockcreate_sid = 0; |
| } |
| return ret; |
| } |
| |
| /* |
| * set the file creation context in a security record to the same as the |
| * objective context of the specified inode |
| */ |
| static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) |
| { |
| struct inode_security_struct *isec = inode->i_security; |
| struct task_security_struct *tsec = new->security; |
| u32 sid = current_sid(); |
| int ret; |
| |
| ret = avc_has_perm(sid, isec->sid, |
| SECCLASS_KERNEL_SERVICE, |
| KERNEL_SERVICE__CREATE_FILES_AS, |
| NULL); |
| |
| if (ret == 0) |
| tsec->create_sid = isec->sid; |
| return ret; |
| } |
| |
| static int selinux_kernel_module_request(char *kmod_name) |
| { |
| u32 sid; |
| struct common_audit_data ad; |
| |
| sid = task_sid(current); |
| |
| COMMON_AUDIT_DATA_INIT(&ad, KMOD); |
| ad.u.kmod_name = kmod_name; |
| |
| return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, |
| SYSTEM__MODULE_REQUEST, &ad); |
| } |
| |
| static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) |
| { |
| return current_has_perm(p, PROCESS__SETPGID); |
| } |
| |
| static int selinux_task_getpgid(struct task_struct *p) |
| { |
| return current_has_perm(p, PROCESS__GETPGID); |
| } |
| |
| static int selinux_task_getsid(struct task_struct *p) |
| { |
| return current_has_perm(p, PROCESS__GETSESSION); |
| } |
| |
| static void selinux_task_getsecid(struct task_struct *p, u32 *secid) |
| { |
| *secid = task_sid(p); |
| } |
| |
| static int selinux_task_setnice(struct task_struct *p, int nice) |
| { |
| int rc; |
| |
| rc = cap_task_setnice(p, nice); |
| if (rc) |
| return rc; |
| |
| return current_has_perm(p, PROCESS__SETSCHED); |
| } |
| |
| static int selinux_task_setioprio(struct task_struct *p, int ioprio) |
| { |
| int rc; |
| |
| rc = cap_task_setioprio(p, ioprio); |
| if (rc) |
| return rc; |
| |
| return current_has_perm(p, PROCESS__SETSCHED); |
| } |
| |
| static int selinux_task_getioprio(struct task_struct *p) |
| { |
| return current_has_perm(p, PROCESS__GETSCHED); |
| } |
| |
| static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, |
| struct rlimit *new_rlim) |
| { |
| struct rlimit *old_rlim = p->signal->rlim + resource; |
| |
| /* Control the ability to change the hard limit (whether |
| lowering or raising it), so that the hard limit can |
| later be used as a safe reset point for the soft limit |
| upon context transitions. See selinux_bprm_committing_creds. */ |
| if (old_rlim->rlim_max != new_rlim->rlim_max) |
| return current_has_perm(p, PROCESS__SETRLIMIT); |
| |
| return 0; |
| } |
| |
| static int selinux_task_setscheduler(struct task_struct *p) |
| { |
| int rc; |
| |
| rc = cap_task_setscheduler(p); |
| if (rc) |
| return rc; |
| |
| return current_has_perm(p, PROCESS__SETSCHED); |
| } |
| |
| static int selinux_task_getscheduler(struct task_struct *p) |
| { |
| return current_has_perm(p, PROCESS__GETSCHED); |
| } |
| |
| static int selinux_task_movememory(struct task_struct *p) |
| { |
| return current_has_perm(p, PROCESS__SETSCHED); |
| } |
| |
| static int selinux_task_kill(struct task_struct *p, struct siginfo *info, |
| int sig, u32 secid) |
| { |
| u32 perm; |
| int rc; |
| |
| if (!sig) |
| perm = PROCESS__SIGNULL; /* null signal; existence test */ |
| else |
| perm = signal_to_av(sig); |
| if (secid) |
| rc = avc_has_perm(secid, task_sid(p), |
| SECCLASS_PROCESS, perm, NULL); |
| else |
| rc = current_has_perm(p, perm); |
| return rc; |
| } |
| |
| static int selinux_task_wait(struct task_struct *p) |
| { |
| return task_has_perm(p, current, PROCESS__SIGCHLD); |
| } |
| |
| static void selinux_task_to_inode(struct task_struct *p, |
| struct inode *inode) |
| { |
| struct inode_security_struct *isec = inode->i_security; |
| u32 sid = task_sid(p); |
| |
| isec->sid = sid; |
| isec->initialized = 1; |
| } |
| |
| /* Returns error only if unable to parse addresses */ |
| static int selinux_parse_skb_ipv4(struct sk_buff *skb, |
| struct common_audit_data *ad, u8 *proto) |
| { |
| int offset, ihlen, ret = -EINVAL; |
| struct iphdr _iph, *ih; |
| |
| offset = skb_network_offset(skb); |
| ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); |
| if (ih == NULL) |
| goto out; |
| |
| ihlen = ih->ihl * 4; |
| if (ihlen < sizeof(_iph)) |
| goto out; |
| |
| ad->u.net.v4info.saddr = ih->saddr; |
| ad->u.net.v4info.daddr = ih->daddr; |
| ret = 0; |
| |
| if (proto) |
| *proto = ih->protocol; |
| |
| switch (ih->protocol) { |
| case IPPROTO_TCP: { |
| struct tcphdr _tcph, *th; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); |
| if (th == NULL) |
| break; |
| |
| ad->u.net.sport = th->source; |
| ad->u.net.dport = th->dest; |
| break; |
| } |
| |
| case IPPROTO_UDP: { |
| struct udphdr _udph, *uh; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); |
| if (uh == NULL) |
| break; |
| |
| ad->u.net.sport = uh->source; |
| ad->u.net.dport = uh->dest; |
| break; |
| } |
| |
| case IPPROTO_DCCP: { |
| struct dccp_hdr _dccph, *dh; |
| |
| if (ntohs(ih->frag_off) & IP_OFFSET) |
| break; |
| |
| offset += ihlen; |
| dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); |
| if (dh == NULL) |
| break; |
| |
| ad->u.net.sport = dh->dccph_sport; |
| ad->u.net.dport = dh->dccph_dport; |
| break; |
| } |
| |
| default: |
| break; |
| } |
| out: |
| return ret; |
| } |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| |
| /* Returns error only if unable to parse addresses */ |
| static int selinux_parse_skb_ipv6(struct sk_buff *skb, |
| struct common_audit_data *ad, u8 *proto) |
| { |
| u8 nexthdr; |
| int ret = -EINVAL, offset; |
| struct ipv6hdr _ipv6h, *ip6; |
| |
| offset = skb_network_offset(skb); |
| ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); |
| if (ip6 == NULL) |
| goto out; |
| |
| ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); |
| ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); |
| ret = 0; |
| |
| nexthdr = ip6->nexthdr; |
| offset += sizeof(_ipv6h); |
| offset = ipv6_skip_exthdr(skb, offset, &nexthdr); |
| if (offset < 0) |
| goto out; |
| |
| if (proto) |
| *proto = nexthdr; |
| |
| switch (nexthdr) { |
| case IPPROTO_TCP: { |
| struct tcphdr _tcph, *th; |
| |
| th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); |
| if (th == NULL) |
| break; |
| |
| ad->u.net.sport = th->source; |
| ad->u.net.dport = th->dest; |
| break; |
| } |
| |
| case IPPROTO_UDP: { |
| struct udphdr _udph, *uh; |
| |
| uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); |
| if (uh == NULL) |
| break; |
| |
| ad->u.net.sport = uh->source; |
| ad->u.net.dport = uh->dest; |
| break; |
| } |
| |
| case IPPROTO_DCCP: { |
| struct dccp_hdr _dccph, *dh; |
| |
| dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); |
| if (dh == NULL) |
| break; |
| |
| ad->u.net.sport = dh->dccph_sport; |
| ad->u.net.dport = dh->dccph_dport; |
| break; |
| } |
| |
| /* includes fragments */ |
| default: |
| break; |
| } |
| out: |
| return ret; |
| } |
| |
| #endif /* IPV6 */ |
| |
| static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, |
| char **_addrp, int src, u8 *proto) |
| { |
| char *addrp; |
| int ret; |
| |
| switch (ad->u.net.family) { |
| case PF_INET: |
| ret = selinux_parse_skb_ipv4(skb, ad, proto); |
| if (ret) |
| goto parse_error; |
| addrp = (char *)(src ? &ad->u.net.v4info.saddr : |
| &ad->u.net.v4info.daddr); |
| goto okay; |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| case PF_INET6: |
| ret = selinux_parse_skb_ipv6(skb, ad, proto); |
| if (ret) |
| goto parse_error; |
| addrp = (char *)(src ? &ad->u.net.v6info.saddr : |
| &ad->u.net.v6info.daddr); |
| goto okay; |
| #endif /* IPV6 */ |
| default: |
| addrp = NULL; |
| goto okay; |
| } |
| |
| parse_error: |
| printk(KERN_WARNING |
| "SELinux: failure in selinux_parse_skb()," |
| " unable to parse packet\n"); |
| return ret; |
| |
| okay: |
| if (_addrp) |
| *_addrp = addrp; |
| return 0; |
| } |
| |
| /** |
| * selinux_skb_peerlbl_sid - Determine the peer label of a packet |
| * @skb: the packet |
| * @family: protocol family |
| * @sid: the packet's peer label SID |
| * |
| * Description: |
| * Check the various different forms of network peer labeling and determine |
| * the peer label/SID for the packet; most of the magic actually occurs in |
| * the security server function security_net_peersid_cmp(). The function |
| * returns zero if the value in @sid is valid (although it may be SECSID_NULL) |
| * or -EACCES if @sid is invalid due to inconsistencies with the different |
| * peer labels. |
| * |
| */ |
| static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) |
| { |
| int err; |
| u32 xfrm_sid; |
| u32 nlbl_sid; |
| u32 nlbl_type; |
| |
| selinux_skb_xfrm_sid(skb, &xfrm_sid); |
| selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); |
| |
| err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); |
| if (unlikely(err)) { |
| printk(KERN_WARNING |
| "SELinux: failure in selinux_skb_peerlbl_sid()," |
| " unable to determine packet's peer label\n"); |
| return -EACCES; |
| } |
| |
| return 0; |
| } |
| |
| /* socket security operations */ |
| |
| static u32 socket_sockcreate_sid(const struct task_security_struct *tsec) |
| { |
| return tsec->sockcreate_sid ? : tsec->sid; |
| } |
| |
| static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct common_audit_data ad; |
| u32 tsid = task_sid(task); |
| |
| if (sksec->sid == SECINITSID_KERNEL) |
| return 0; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.sk = sk; |
| |
| return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); |
| } |
| |
| static int selinux_socket_create(int family, int type, |
| int protocol, int kern) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| u32 newsid; |
| u16 secclass; |
| |
| if (kern) |
| return 0; |
| |
| newsid = socket_sockcreate_sid(tsec); |
| secclass = socket_type_to_security_class(family, type, protocol); |
| return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); |
| } |
| |
| static int selinux_socket_post_create(struct socket *sock, int family, |
| int type, int protocol, int kern) |
| { |
| const struct task_security_struct *tsec = current_security(); |
| struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; |
| struct sk_security_struct *sksec; |
| int err = 0; |
| |
| if (kern) |
| isec->sid = SECINITSID_KERNEL; |
| else |
| isec->sid = socket_sockcreate_sid(tsec); |
| |
| isec->sclass = socket_type_to_security_class(family, type, protocol); |
| isec->initialized = 1; |
| |
| if (sock->sk) { |
| sksec = sock->sk->sk_security; |
| sksec->sid = isec->sid; |
| sksec->sclass = isec->sclass; |
| err = selinux_netlbl_socket_post_create(sock->sk, family); |
| } |
| |
| return err; |
| } |
| |
| /* Range of port numbers used to automatically bind. |
| Need to determine whether we should perform a name_bind |
| permission check between the socket and the port number. */ |
| |
| static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) |
| { |
| struct sock *sk = sock->sk; |
| u16 family; |
| int err; |
| |
| err = sock_has_perm(current, sk, SOCKET__BIND); |
| if (err) |
| goto out; |
| |
| /* |
| * If PF_INET or PF_INET6, check name_bind permission for the port. |
| * Multiple address binding for SCTP is not supported yet: we just |
| * check the first address now. |
| */ |
| family = sk->sk_family; |
| if (family == PF_INET || family == PF_INET6) { |
| char *addrp; |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct common_audit_data ad; |
| struct sockaddr_in *addr4 = NULL; |
| struct sockaddr_in6 *addr6 = NULL; |
| unsigned short snum; |
| u32 sid, node_perm; |
| |
| if (family == PF_INET) { |
| addr4 = (struct sockaddr_in *)address; |
| snum = ntohs(addr4->sin_port); |
| addrp = (char *)&addr4->sin_addr.s_addr; |
| } else { |
| addr6 = (struct sockaddr_in6 *)address; |
| snum = ntohs(addr6->sin6_port); |
| addrp = (char *)&addr6->sin6_addr.s6_addr; |
| } |
| |
| if (snum) { |
| int low, high; |
| |
| inet_get_local_port_range(&low, &high); |
| |
| if (snum < max(PROT_SOCK, low) || snum > high) { |
| err = sel_netport_sid(sk->sk_protocol, |
| snum, &sid); |
| if (err) |
| goto out; |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.sport = htons(snum); |
| ad.u.net.family = family; |
| err = avc_has_perm(sksec->sid, sid, |
| sksec->sclass, |
| SOCKET__NAME_BIND, &ad); |
| if (err) |
| goto out; |
| } |
| } |
| |
| switch (sksec->sclass) { |
| case SECCLASS_TCP_SOCKET: |
| node_perm = TCP_SOCKET__NODE_BIND; |
| break; |
| |
| case SECCLASS_UDP_SOCKET: |
| node_perm = UDP_SOCKET__NODE_BIND; |
| break; |
| |
| case SECCLASS_DCCP_SOCKET: |
| node_perm = DCCP_SOCKET__NODE_BIND; |
| break; |
| |
| default: |
| node_perm = RAWIP_SOCKET__NODE_BIND; |
| break; |
| } |
| |
| err = sel_netnode_sid(addrp, family, &sid); |
| if (err) |
| goto out; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.sport = htons(snum); |
| ad.u.net.family = family; |
| |
| if (family == PF_INET) |
| ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; |
| else |
| ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); |
| |
| err = avc_has_perm(sksec->sid, sid, |
| sksec->sclass, node_perm, &ad); |
| if (err) |
| goto out; |
| } |
| out: |
| return err; |
| } |
| |
| static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) |
| { |
| struct sock *sk = sock->sk; |
| struct sk_security_struct *sksec = sk->sk_security; |
| int err; |
| |
| err = sock_has_perm(current, sk, SOCKET__CONNECT); |
| if (err) |
| return err; |
| |
| /* |
| * If a TCP or DCCP socket, check name_connect permission for the port. |
| */ |
| if (sksec->sclass == SECCLASS_TCP_SOCKET || |
| sksec->sclass == SECCLASS_DCCP_SOCKET) { |
| struct common_audit_data ad; |
| struct sockaddr_in *addr4 = NULL; |
| struct sockaddr_in6 *addr6 = NULL; |
| unsigned short snum; |
| u32 sid, perm; |
| |
| if (sk->sk_family == PF_INET) { |
| addr4 = (struct sockaddr_in *)address; |
| if (addrlen < sizeof(struct sockaddr_in)) |
| return -EINVAL; |
| snum = ntohs(addr4->sin_port); |
| } else { |
| addr6 = (struct sockaddr_in6 *)address; |
| if (addrlen < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| snum = ntohs(addr6->sin6_port); |
| } |
| |
| err = sel_netport_sid(sk->sk_protocol, snum, &sid); |
| if (err) |
| goto out; |
| |
| perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? |
| TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.dport = htons(snum); |
| ad.u.net.family = sk->sk_family; |
| err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); |
| if (err) |
| goto out; |
| } |
| |
| err = selinux_netlbl_socket_connect(sk, address); |
| |
| out: |
| return err; |
| } |
| |
| static int selinux_socket_listen(struct socket *sock, int backlog) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__LISTEN); |
| } |
| |
| static int selinux_socket_accept(struct socket *sock, struct socket *newsock) |
| { |
| int err; |
| struct inode_security_struct *isec; |
| struct inode_security_struct *newisec; |
| |
| err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); |
| if (err) |
| return err; |
| |
| newisec = SOCK_INODE(newsock)->i_security; |
| |
| isec = SOCK_INODE(sock)->i_security; |
| newisec->sclass = isec->sclass; |
| newisec->sid = isec->sid; |
| newisec->initialized = 1; |
| |
| return 0; |
| } |
| |
| static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, |
| int size) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__WRITE); |
| } |
| |
| static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, |
| int size, int flags) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__READ); |
| } |
| |
| static int selinux_socket_getsockname(struct socket *sock) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__GETATTR); |
| } |
| |
| static int selinux_socket_getpeername(struct socket *sock) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__GETATTR); |
| } |
| |
| static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) |
| { |
| int err; |
| |
| err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); |
| if (err) |
| return err; |
| |
| return selinux_netlbl_socket_setsockopt(sock, level, optname); |
| } |
| |
| static int selinux_socket_getsockopt(struct socket *sock, int level, |
| int optname) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__GETOPT); |
| } |
| |
| static int selinux_socket_shutdown(struct socket *sock, int how) |
| { |
| return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); |
| } |
| |
| static int selinux_socket_unix_stream_connect(struct sock *sock, |
| struct sock *other, |
| struct sock *newsk) |
| { |
| struct sk_security_struct *sksec_sock = sock->sk_security; |
| struct sk_security_struct *sksec_other = other->sk_security; |
| struct sk_security_struct *sksec_new = newsk->sk_security; |
| struct common_audit_data ad; |
| int err; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.sk = other; |
| |
| err = avc_has_perm(sksec_sock->sid, sksec_other->sid, |
| sksec_other->sclass, |
| UNIX_STREAM_SOCKET__CONNECTTO, &ad); |
| if (err) |
| return err; |
| |
| /* server child socket */ |
| sksec_new->peer_sid = sksec_sock->sid; |
| err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, |
| &sksec_new->sid); |
| if (err) |
| return err; |
| |
| /* connecting socket */ |
| sksec_sock->peer_sid = sksec_new->sid; |
| |
| return 0; |
| } |
| |
| static int selinux_socket_unix_may_send(struct socket *sock, |
| struct socket *other) |
| { |
| struct sk_security_struct *ssec = sock->sk->sk_security; |
| struct sk_security_struct *osec = other->sk->sk_security; |
| struct common_audit_data ad; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.sk = other->sk; |
| |
| return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, |
| &ad); |
| } |
| |
| static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, |
| u32 peer_sid, |
| struct common_audit_data *ad) |
| { |
| int err; |
| u32 if_sid; |
| u32 node_sid; |
| |
| err = sel_netif_sid(ifindex, &if_sid); |
| if (err) |
| return err; |
| err = avc_has_perm(peer_sid, if_sid, |
| SECCLASS_NETIF, NETIF__INGRESS, ad); |
| if (err) |
| return err; |
| |
| err = sel_netnode_sid(addrp, family, &node_sid); |
| if (err) |
| return err; |
| return avc_has_perm(peer_sid, node_sid, |
| SECCLASS_NODE, NODE__RECVFROM, ad); |
| } |
| |
| static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, |
| u16 family) |
| { |
| int err = 0; |
| struct sk_security_struct *sksec = sk->sk_security; |
| u32 peer_sid; |
| u32 sk_sid = sksec->sid; |
| struct common_audit_data ad; |
| char *addrp; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.netif = skb->skb_iif; |
| ad.u.net.family = family; |
| err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); |
| if (err) |
| return err; |
| |
| if (selinux_secmark_enabled()) { |
| err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, |
| PACKET__RECV, &ad); |
| if (err) |
| return err; |
| } |
| |
| if (selinux_policycap_netpeer) { |
| err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); |
| if (err) |
| return err; |
| err = avc_has_perm(sk_sid, peer_sid, |
| SECCLASS_PEER, PEER__RECV, &ad); |
| if (err) |
| selinux_netlbl_err(skb, err, 0); |
| } else { |
| err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); |
| if (err) |
| return err; |
| err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); |
| } |
| |
| return err; |
| } |
| |
| static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| { |
| int err; |
| struct sk_security_struct *sksec = sk->sk_security; |
| u16 family = sk->sk_family; |
| u32 sk_sid = sksec->sid; |
| struct common_audit_data ad; |
| char *addrp; |
| u8 secmark_active; |
| u8 peerlbl_active; |
| |
| if (family != PF_INET && family != PF_INET6) |
| return 0; |
| |
| /* Handle mapped IPv4 packets arriving via IPv6 sockets */ |
| if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| |
| /* If any sort of compatibility mode is enabled then handoff processing |
| * to the selinux_sock_rcv_skb_compat() function to deal with the |
| * special handling. We do this in an attempt to keep this function |
| * as fast and as clean as possible. */ |
| if (!selinux_policycap_netpeer) |
| return selinux_sock_rcv_skb_compat(sk, skb, family); |
| |
| secmark_active = selinux_secmark_enabled(); |
| peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); |
| if (!secmark_active && !peerlbl_active) |
| return 0; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.netif = skb->skb_iif; |
| ad.u.net.family = family; |
| err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); |
| if (err) |
| return err; |
| |
| if (peerlbl_active) { |
| u32 peer_sid; |
| |
| err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); |
| if (err) |
| return err; |
| err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family, |
| peer_sid, &ad); |
| if (err) { |
| selinux_netlbl_err(skb, err, 0); |
| return err; |
| } |
| err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, |
| PEER__RECV, &ad); |
| if (err) |
| selinux_netlbl_err(skb, err, 0); |
| } |
| |
| if (secmark_active) { |
| err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, |
| PACKET__RECV, &ad); |
| if (err) |
| return err; |
| } |
| |
| return err; |
| } |
| |
| static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, |
| int __user *optlen, unsigned len) |
| { |
| int err = 0; |
| char *scontext; |
| u32 scontext_len; |
| struct sk_security_struct *sksec = sock->sk->sk_security; |
| u32 peer_sid = SECSID_NULL; |
| |
| if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || |
| sksec->sclass == SECCLASS_TCP_SOCKET) |
| peer_sid = sksec->peer_sid; |
| if (peer_sid == SECSID_NULL) |
| return -ENOPROTOOPT; |
| |
| err = security_sid_to_context(peer_sid, &scontext, &scontext_len); |
| if (err) |
| return err; |
| |
| if (scontext_len > len) { |
| err = -ERANGE; |
| goto out_len; |
| } |
| |
| if (copy_to_user(optval, scontext, scontext_len)) |
| err = -EFAULT; |
| |
| out_len: |
| if (put_user(scontext_len, optlen)) |
| err = -EFAULT; |
| kfree(scontext); |
| return err; |
| } |
| |
| static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) |
| { |
| u32 peer_secid = SECSID_NULL; |
| u16 family; |
| |
| if (skb && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| else if (skb && skb->protocol == htons(ETH_P_IPV6)) |
| family = PF_INET6; |
| else if (sock) |
| family = sock->sk->sk_family; |
| else |
| goto out; |
| |
| if (sock && family == PF_UNIX) |
| selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); |
| else if (skb) |
| selinux_skb_peerlbl_sid(skb, family, &peer_secid); |
| |
| out: |
| *secid = peer_secid; |
| if (peer_secid == SECSID_NULL) |
| return -EINVAL; |
| return 0; |
| } |
| |
| static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
| { |
| struct sk_security_struct *sksec; |
| |
| sksec = kzalloc(sizeof(*sksec), priority); |
| if (!sksec) |
| return -ENOMEM; |
| |
| sksec->peer_sid = SECINITSID_UNLABELED; |
| sksec->sid = SECINITSID_UNLABELED; |
| selinux_netlbl_sk_security_reset(sksec); |
| sk->sk_security = sksec; |
| |
| return 0; |
| } |
| |
| static void selinux_sk_free_security(struct sock *sk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| sk->sk_security = NULL; |
| selinux_netlbl_sk_security_free(sksec); |
| kfree(sksec); |
| } |
| |
| static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| struct sk_security_struct *newsksec = newsk->sk_security; |
| |
| newsksec->sid = sksec->sid; |
| newsksec->peer_sid = sksec->peer_sid; |
| newsksec->sclass = sksec->sclass; |
| |
| selinux_netlbl_sk_security_reset(newsksec); |
| } |
| |
| static void selinux_sk_getsecid(struct sock *sk, u32 *secid) |
| { |
| if (!sk) |
| *secid = SECINITSID_ANY_SOCKET; |
| else { |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| *secid = sksec->sid; |
| } |
| } |
| |
| static void selinux_sock_graft(struct sock *sk, struct socket *parent) |
| { |
| struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || |
| sk->sk_family == PF_UNIX) |
| isec->sid = sksec->sid; |
| sksec->sclass = isec->sclass; |
| } |
| |
| static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, |
| struct request_sock *req) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| int err; |
| u16 family = sk->sk_family; |
| u32 newsid; |
| u32 peersid; |
| |
| /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
| if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| |
| err = selinux_skb_peerlbl_sid(skb, family, &peersid); |
| if (err) |
| return err; |
| if (peersid == SECSID_NULL) { |
| req->secid = sksec->sid; |
| req->peer_secid = SECSID_NULL; |
| } else { |
| err = security_sid_mls_copy(sksec->sid, peersid, &newsid); |
| if (err) |
| return err; |
| req->secid = newsid; |
| req->peer_secid = peersid; |
| } |
| |
| return selinux_netlbl_inet_conn_request(req, family); |
| } |
| |
| static void selinux_inet_csk_clone(struct sock *newsk, |
| const struct request_sock *req) |
| { |
| struct sk_security_struct *newsksec = newsk->sk_security; |
| |
| newsksec->sid = req->secid; |
| newsksec->peer_sid = req->peer_secid; |
| /* NOTE: Ideally, we should also get the isec->sid for the |
| new socket in sync, but we don't have the isec available yet. |
| So we will wait until sock_graft to do it, by which |
| time it will have been created and available. */ |
| |
| /* We don't need to take any sort of lock here as we are the only |
| * thread with access to newsksec */ |
| selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); |
| } |
| |
| static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) |
| { |
| u16 family = sk->sk_family; |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
| if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
| family = PF_INET; |
| |
| selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); |
| } |
| |
| static int selinux_secmark_relabel_packet(u32 sid) |
| { |
| const struct task_security_struct *__tsec; |
| u32 tsid; |
| |
| __tsec = current_security(); |
| tsid = __tsec->sid; |
| |
| return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); |
| } |
| |
| static void selinux_secmark_refcount_inc(void) |
| { |
| atomic_inc(&selinux_secmark_refcount); |
| } |
| |
| static void selinux_secmark_refcount_dec(void) |
| { |
| atomic_dec(&selinux_secmark_refcount); |
| } |
| |
| static void selinux_req_classify_flow(const struct request_sock *req, |
| struct flowi *fl) |
| { |
| fl->secid = req->secid; |
| } |
| |
| static int selinux_tun_dev_create(void) |
| { |
| u32 sid = current_sid(); |
| |
| /* we aren't taking into account the "sockcreate" SID since the socket |
| * that is being created here is not a socket in the traditional sense, |
| * instead it is a private sock, accessible only to the kernel, and |
| * representing a wide range of network traffic spanning multiple |
| * connections unlike traditional sockets - check the TUN driver to |
| * get a better understanding of why this socket is special */ |
| |
| return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, |
| NULL); |
| } |
| |
| static void selinux_tun_dev_post_create(struct sock *sk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| /* we don't currently perform any NetLabel based labeling here and it |
| * isn't clear that we would want to do so anyway; while we could apply |
| * labeling without the support of the TUN user the resulting labeled |
| * traffic from the other end of the connection would almost certainly |
| * cause confusion to the TUN user that had no idea network labeling |
| * protocols were being used */ |
| |
| /* see the comments in selinux_tun_dev_create() about why we don't use |
| * the sockcreate SID here */ |
| |
| sksec->sid = current_sid(); |
| sksec->sclass = SECCLASS_TUN_SOCKET; |
| } |
| |
| static int selinux_tun_dev_attach(struct sock *sk) |
| { |
| struct sk_security_struct *sksec = sk->sk_security; |
| u32 sid = current_sid(); |
| int err; |
| |
| err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, |
| TUN_SOCKET__RELABELFROM, NULL); |
| if (err) |
| return err; |
| err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, |
| TUN_SOCKET__RELABELTO, NULL); |
| if (err) |
| return err; |
| |
| sksec->sid = sid; |
| |
| return 0; |
| } |
| |
| static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) |
| { |
| int err = 0; |
| u32 perm; |
| struct nlmsghdr *nlh; |
| struct sk_security_struct *sksec = sk->sk_security; |
| |
| if (skb->len < NLMSG_SPACE(0)) { |
| err = -EINVAL; |
| goto out; |
| } |
| nlh = nlmsg_hdr(skb); |
| |
| err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); |
| if (err) { |
| if (err == -EINVAL) { |
| audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, |
| "SELinux: unrecognized netlink message" |
| " type=%hu for sclass=%hu\n", |
| nlh->nlmsg_type, sksec->sclass); |
| if (!selinux_enforcing || security_get_allow_unknown()) |
| err = 0; |
| } |
| |
| /* Ignore */ |
| if (err == -ENOENT) |
| err = 0; |
| goto out; |
| } |
| |
| err = sock_has_perm(current, sk, perm); |
| out: |
| return err; |
| } |
| |
| #ifdef CONFIG_NETFILTER |
| |
| static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, |
| u16 family) |
| { |
| int err; |
| char *addrp; |
| u32 peer_sid; |
| struct common_audit_data ad; |
| u8 secmark_active; |
| u8 netlbl_active; |
| u8 peerlbl_active; |
| |
| if (!selinux_policycap_netpeer) |
| return NF_ACCEPT; |
| |
| secmark_active = selinux_secmark_enabled(); |
| netlbl_active = netlbl_enabled(); |
| peerlbl_active = netlbl_active || selinux_xfrm_enabled(); |
| if (!secmark_active && !peerlbl_active) |
| return NF_ACCEPT; |
| |
| if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) |
| return NF_DROP; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.netif = ifindex; |
| ad.u.net.family = family; |
| if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) |
| return NF_DROP; |
| |
| if (peerlbl_active) { |
| err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, |
| peer_sid, &ad); |
| if (err) { |
| selinux_netlbl_err(skb, err, 1); |
| return NF_DROP; |
| } |
| } |
| |
| if (secmark_active) |
| if (avc_has_perm(peer_sid, skb->secmark, |
| SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) |
| return NF_DROP; |
| |
| if (netlbl_active) |
| /* we do this in the FORWARD path and not the POST_ROUTING |
| * path because we want to make sure we apply the necessary |
| * labeling before IPsec is applied so we can leverage AH |
| * protection */ |
| if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) |
| return NF_DROP; |
| |
| return NF_ACCEPT; |
| } |
| |
| static unsigned int selinux_ipv4_forward(unsigned int hooknum, |
| struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| return selinux_ip_forward(skb, in->ifindex, PF_INET); |
| } |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| static unsigned int selinux_ipv6_forward(unsigned int hooknum, |
| struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| return selinux_ip_forward(skb, in->ifindex, PF_INET6); |
| } |
| #endif /* IPV6 */ |
| |
| static unsigned int selinux_ip_output(struct sk_buff *skb, |
| u16 family) |
| { |
| u32 sid; |
| |
| if (!netlbl_enabled()) |
| return NF_ACCEPT; |
| |
| /* we do this in the LOCAL_OUT path and not the POST_ROUTING path |
| * because we want to make sure we apply the necessary labeling |
| * before IPsec is applied so we can leverage AH protection */ |
| if (skb->sk) { |
| struct sk_security_struct *sksec = skb->sk->sk_security; |
| sid = sksec->sid; |
| } else |
| sid = SECINITSID_KERNEL; |
| if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) |
| return NF_DROP; |
| |
| return NF_ACCEPT; |
| } |
| |
| static unsigned int selinux_ipv4_output(unsigned int hooknum, |
| struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| return selinux_ip_output(skb, PF_INET); |
| } |
| |
| static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, |
| int ifindex, |
| u16 family) |
| { |
| struct sock *sk = skb->sk; |
| struct sk_security_struct *sksec; |
| struct common_audit_data ad; |
| char *addrp; |
| u8 proto; |
| |
| if (sk == NULL) |
| return NF_ACCEPT; |
| sksec = sk->sk_security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.netif = ifindex; |
| ad.u.net.family = family; |
| if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) |
| return NF_DROP; |
| |
| if (selinux_secmark_enabled()) |
| if (avc_has_perm(sksec->sid, skb->secmark, |
| SECCLASS_PACKET, PACKET__SEND, &ad)) |
| return NF_DROP; |
| |
| if (selinux_policycap_netpeer) |
| if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) |
| return NF_DROP; |
| |
| return NF_ACCEPT; |
| } |
| |
| static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, |
| u16 family) |
| { |
| u32 secmark_perm; |
| u32 peer_sid; |
| struct sock *sk; |
| struct common_audit_data ad; |
| char *addrp; |
| u8 secmark_active; |
| u8 peerlbl_active; |
| |
| /* If any sort of compatibility mode is enabled then handoff processing |
| * to the selinux_ip_postroute_compat() function to deal with the |
| * special handling. We do this in an attempt to keep this function |
| * as fast and as clean as possible. */ |
| if (!selinux_policycap_netpeer) |
| return selinux_ip_postroute_compat(skb, ifindex, family); |
| #ifdef CONFIG_XFRM |
| /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec |
| * packet transformation so allow the packet to pass without any checks |
| * since we'll have another chance to perform access control checks |
| * when the packet is on it's final way out. |
| * NOTE: there appear to be some IPv6 multicast cases where skb->dst |
| * is NULL, in this case go ahead and apply access control. */ |
| if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) |
| return NF_ACCEPT; |
| #endif |
| secmark_active = selinux_secmark_enabled(); |
| peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); |
| if (!secmark_active && !peerlbl_active) |
| return NF_ACCEPT; |
| |
| /* if the packet is being forwarded then get the peer label from the |
| * packet itself; otherwise check to see if it is from a local |
| * application or the kernel, if from an application get the peer label |
| * from the sending socket, otherwise use the kernel's sid */ |
| sk = skb->sk; |
| if (sk == NULL) { |
| switch (family) { |
| case PF_INET: |
| if (IPCB(skb)->flags & IPSKB_FORWARDED) |
| secmark_perm = PACKET__FORWARD_OUT; |
| else |
| secmark_perm = PACKET__SEND; |
| break; |
| case PF_INET6: |
| if (IP6CB(skb)->flags & IP6SKB_FORWARDED) |
| secmark_perm = PACKET__FORWARD_OUT; |
| else |
| secmark_perm = PACKET__SEND; |
| break; |
| default: |
| return NF_DROP; |
| } |
| if (secmark_perm == PACKET__FORWARD_OUT) { |
| if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) |
| return NF_DROP; |
| } else |
| peer_sid = SECINITSID_KERNEL; |
| } else { |
| struct sk_security_struct *sksec = sk->sk_security; |
| peer_sid = sksec->sid; |
| secmark_perm = PACKET__SEND; |
| } |
| |
| COMMON_AUDIT_DATA_INIT(&ad, NET); |
| ad.u.net.netif = ifindex; |
| ad.u.net.family = family; |
| if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) |
| return NF_DROP; |
| |
| if (secmark_active) |
| if (avc_has_perm(peer_sid, skb->secmark, |
| SECCLASS_PACKET, secmark_perm, &ad)) |
| return NF_DROP; |
| |
| if (peerlbl_active) { |
| u32 if_sid; |
| u32 node_sid; |
| |
| if (sel_netif_sid(ifindex, &if_sid)) |
| return NF_DROP; |
| if (avc_has_perm(peer_sid, if_sid, |
| SECCLASS_NETIF, NETIF__EGRESS, &ad)) |
| return NF_DROP; |
| |
| if (sel_netnode_sid(addrp, family, &node_sid)) |
| return NF_DROP; |
| if (avc_has_perm(peer_sid, node_sid, |
| SECCLASS_NODE, NODE__SENDTO, &ad)) |
| return NF_DROP; |
| } |
| |
| return NF_ACCEPT; |
| } |
| |
| static unsigned int selinux_ipv4_postroute(unsigned int hooknum, |
| struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| return selinux_ip_postroute(skb, out->ifindex, PF_INET); |
| } |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| static unsigned int selinux_ipv6_postroute(unsigned int hooknum, |
| struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| return selinux_ip_postroute(skb, out->ifindex, PF_INET6); |
| } |
| #endif /* IPV6 */ |
| |
| #endif /* CONFIG_NETFILTER */ |
| |
| static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) |
| { |
| int err; |
| |
| err = cap_netlink_send(sk, skb); |
| if (err) |
| return err; |
| |
| return selinux_nlmsg_perm(sk, skb); |
| } |
| |
| static int selinux_netlink_recv(struct sk_buff *skb, int capability) |
| { |
| int err; |
| struct common_audit_data ad; |
| |
| err = cap_netlink_recv(skb, capability); |
| if (err) |
| return err; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, CAP); |
| ad.u.cap = capability; |
| |
| return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, |
| SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); |
| } |
| |
| static int ipc_alloc_security(struct task_struct *task, |
| struct kern_ipc_perm *perm, |
| u16 sclass) |
| { |
| struct ipc_security_struct *isec; |
| u32 sid; |
| |
| isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); |
| if (!isec) |
| return -ENOMEM; |
| |
| sid = task_sid(task); |
| isec->sclass = sclass; |
| isec->sid = sid; |
| perm->security = isec; |
| |
| return 0; |
| } |
| |
| static void ipc_free_security(struct kern_ipc_perm *perm) |
| { |
| struct ipc_security_struct *isec = perm->security; |
| perm->security = NULL; |
| kfree(isec); |
| } |
| |
| static int msg_msg_alloc_security(struct msg_msg *msg) |
| { |
| struct msg_security_struct *msec; |
| |
| msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); |
| if (!msec) |
| return -ENOMEM; |
| |
| msec->sid = SECINITSID_UNLABELED; |
| msg->security = msec; |
| |
| return 0; |
| } |
| |
| static void msg_msg_free_security(struct msg_msg *msg) |
| { |
| struct msg_security_struct *msec = msg->security; |
| |
| msg->security = NULL; |
| kfree(msec); |
| } |
| |
| static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, |
| u32 perms) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = ipc_perms->security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = ipc_perms->key; |
| |
| return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); |
| } |
| |
| static int selinux_msg_msg_alloc_security(struct msg_msg *msg) |
| { |
| return msg_msg_alloc_security(msg); |
| } |
| |
| static void selinux_msg_msg_free_security(struct msg_msg *msg) |
| { |
| msg_msg_free_security(msg); |
| } |
| |
| /* message queue security operations */ |
| static int selinux_msg_queue_alloc_security(struct msg_queue *msq) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| int rc; |
| |
| rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); |
| if (rc) |
| return rc; |
| |
| isec = msq->q_perm.security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = msq->q_perm.key; |
| |
| rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__CREATE, &ad); |
| if (rc) { |
| ipc_free_security(&msq->q_perm); |
| return rc; |
| } |
| return 0; |
| } |
| |
| static void selinux_msg_queue_free_security(struct msg_queue *msq) |
| { |
| ipc_free_security(&msq->q_perm); |
| } |
| |
| static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = msq->q_perm.security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = msq->q_perm.key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__ASSOCIATE, &ad); |
| } |
| |
| static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) |
| { |
| int err; |
| int perms; |
| |
| switch (cmd) { |
| case IPC_INFO: |
| case MSG_INFO: |
| /* No specific object, just general system-wide information. */ |
| return task_has_system(current, SYSTEM__IPC_INFO); |
| case IPC_STAT: |
| case MSG_STAT: |
| perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; |
| break; |
| case IPC_SET: |
| perms = MSGQ__SETATTR; |
| break; |
| case IPC_RMID: |
| perms = MSGQ__DESTROY; |
| break; |
| default: |
| return 0; |
| } |
| |
| err = ipc_has_perm(&msq->q_perm, perms); |
| return err; |
| } |
| |
| static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) |
| { |
| struct ipc_security_struct *isec; |
| struct msg_security_struct *msec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| int rc; |
| |
| isec = msq->q_perm.security; |
| msec = msg->security; |
| |
| /* |
| * First time through, need to assign label to the message |
| */ |
| if (msec->sid == SECINITSID_UNLABELED) { |
| /* |
| * Compute new sid based on current process and |
| * message queue this message will be stored in |
| */ |
| rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, |
| &msec->sid); |
| if (rc) |
| return rc; |
| } |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = msq->q_perm.key; |
| |
| /* Can this process write to the queue? */ |
| rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__WRITE, &ad); |
| if (!rc) |
| /* Can this process send the message */ |
| rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, |
| MSG__SEND, &ad); |
| if (!rc) |
| /* Can the message be put in the queue? */ |
| rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, |
| MSGQ__ENQUEUE, &ad); |
| |
| return rc; |
| } |
| |
| static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, |
| struct task_struct *target, |
| long type, int mode) |
| { |
| struct ipc_security_struct *isec; |
| struct msg_security_struct *msec; |
| struct common_audit_data ad; |
| u32 sid = task_sid(target); |
| int rc; |
| |
| isec = msq->q_perm.security; |
| msec = msg->security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = msq->q_perm.key; |
| |
| rc = avc_has_perm(sid, isec->sid, |
| SECCLASS_MSGQ, MSGQ__READ, &ad); |
| if (!rc) |
| rc = avc_has_perm(sid, msec->sid, |
| SECCLASS_MSG, MSG__RECEIVE, &ad); |
| return rc; |
| } |
| |
| /* Shared Memory security operations */ |
| static int selinux_shm_alloc_security(struct shmid_kernel *shp) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| int rc; |
| |
| rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); |
| if (rc) |
| return rc; |
| |
| isec = shp->shm_perm.security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = shp->shm_perm.key; |
| |
| rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, |
| SHM__CREATE, &ad); |
| if (rc) { |
| ipc_free_security(&shp->shm_perm); |
| return rc; |
| } |
| return 0; |
| } |
| |
| static void selinux_shm_free_security(struct shmid_kernel *shp) |
| { |
| ipc_free_security(&shp->shm_perm); |
| } |
| |
| static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = shp->shm_perm.security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = shp->shm_perm.key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_SHM, |
| SHM__ASSOCIATE, &ad); |
| } |
| |
| /* Note, at this point, shp is locked down */ |
| static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) |
| { |
| int perms; |
| int err; |
| |
| switch (cmd) { |
| case IPC_INFO: |
| case SHM_INFO: |
| /* No specific object, just general system-wide information. */ |
| return task_has_system(current, SYSTEM__IPC_INFO); |
| case IPC_STAT: |
| case SHM_STAT: |
| perms = SHM__GETATTR | SHM__ASSOCIATE; |
| break; |
| case IPC_SET: |
| perms = SHM__SETATTR; |
| break; |
| case SHM_LOCK: |
| case SHM_UNLOCK: |
| perms = SHM__LOCK; |
| break; |
| case IPC_RMID: |
| perms = SHM__DESTROY; |
| break; |
| default: |
| return 0; |
| } |
| |
| err = ipc_has_perm(&shp->shm_perm, perms); |
| return err; |
| } |
| |
| static int selinux_shm_shmat(struct shmid_kernel *shp, |
| char __user *shmaddr, int shmflg) |
| { |
| u32 perms; |
| |
| if (shmflg & SHM_RDONLY) |
| perms = SHM__READ; |
| else |
| perms = SHM__READ | SHM__WRITE; |
| |
| return ipc_has_perm(&shp->shm_perm, perms); |
| } |
| |
| /* Semaphore security operations */ |
| static int selinux_sem_alloc_security(struct sem_array *sma) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| int rc; |
| |
| rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); |
| if (rc) |
| return rc; |
| |
| isec = sma->sem_perm.security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = sma->sem_perm.key; |
| |
| rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, |
| SEM__CREATE, &ad); |
| if (rc) { |
| ipc_free_security(&sma->sem_perm); |
| return rc; |
| } |
| return 0; |
| } |
| |
| static void selinux_sem_free_security(struct sem_array *sma) |
| { |
| ipc_free_security(&sma->sem_perm); |
| } |
| |
| static int selinux_sem_associate(struct sem_array *sma, int semflg) |
| { |
| struct ipc_security_struct *isec; |
| struct common_audit_data ad; |
| u32 sid = current_sid(); |
| |
| isec = sma->sem_perm.security; |
| |
| COMMON_AUDIT_DATA_INIT(&ad, IPC); |
| ad.u.ipc_id = sma->sem_perm.key; |
| |
| return avc_has_perm(sid, isec->sid, SECCLASS_SEM, |
| SEM__ASSOCIATE, &ad); |
| } |
| |
| /* Note, at this point, sma is locked down */ |
| static int selinux_sem_semctl(struct sem_array *sma, int cmd) |
| { |
| int err; |
| u32 perms; |
| |
| switch (cmd) { |
| case IPC_INFO: |
| case SEM_INFO: |
| /* No specific object, just general system-wide information. */ |
| return task_has_system(current, SYSTEM__IPC_INFO); |
| case GETPID: |
| case GETNCNT: |
| case GETZCNT: |
| perms = SEM__GETATTR; |
| break; |
| case GETVAL: |
| case GETALL: |
| perms = SEM__READ; |
| break; |
| case SETVAL: |
| case SETALL: |
| perms = SEM__WRITE; |
| break; |
| case IPC_RMID: |
| perms = SEM__DESTROY; |
| break; |
| case IPC_SET: |
| perms = SEM__SETATTR; |
| break; |
| case IPC_STAT: |
| case SEM_STAT: |
| perms = SEM__GETATTR | SEM__ASSOCIATE; |
| break; |
| default: |
| return 0; |
| } |
| |
| err = ipc_has_perm(&sma->sem_perm, perms); |
| return err; |
| } |
| |
| static int selinux_sem_semop(struct sem_array *sma, |
| struct sembuf *sops, unsigned nsops, int alter) |
| { |
| u32 perms; |
| |
| if (alter) |
| perms = SEM__READ | SEM__WRITE; |
| else |
| perms = SEM__READ; |
| |
| return ipc_has_perm(&sma->sem_perm, perms); |
| } |
| |
| static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) |
| { |
| u32 av = 0; |
| |
| av = 0; |
| if (flag & S_IRUGO) |
| av |= IPC__UNIX_READ; |
| if (flag & S_IWUGO) |
| av |= IPC__UNIX_WRITE; |
| |
| if (av == 0) |
| return 0; |
| |
| return ipc_has_perm(ipcp, av); |
| } |
| |
| static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) |
| { |
| struct ipc_security_struct *isec = ipcp->security; |
| *secid = isec->sid; |
| } |
| |
| static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) |
| { |
| if (inode) |
| inode_doinit_with_dentry(inode, dentry); |
| } |
| |
| static int selinux_getprocattr(struct task_struct *p, |
| char *name, char **value) |
| { |
| const struct task_security_struct *__tsec; |
| u32 sid; |
| int error; |
| unsigned len; |
| |
| if (current != p) { |
| error = current_has_perm(p, PROCESS__GETATTR); |
| if (error) |
| return error; |
| } |
| |
| rcu_read_lock(); |
| __tsec = __task_cred(p)->security; |
| |
| if (!strcmp(name, "current")) |
| sid = __tsec->sid; |
| else if (!strcmp(name, "prev")) |
| sid = __tsec->osid; |
| else if (!strcmp(name, "exec")) |
| sid = __tsec->exec_sid; |
| else if (!strcmp(name, "fscreate")) |
| sid = __tsec->create_sid; |
| else if (!strcmp(name, "keycreate")) |
| sid = __tsec->keycreate_sid; |
| else if (!strcmp(name, "sockcreate")) |
| sid = __tsec->sockcreate_sid; |
| else |
| goto invalid; |
| rcu_read_unlock(); |
| |
| if (!sid) |
| return 0; |
| |
| error = security_sid_to_context(sid, value, &len); |
| if (error) |
| return error; |
| return len; |
| |
| invalid: |
| rcu_read_unlock(); |
| return -EINVAL; |
| } |
| |
| static int selinux_setprocattr(struct task_struct *p, |
| char *name, void *value, size_t size) |
| { |
| struct task_security_struct *tsec; |
| struct task_struct *tracer; |
| struct cred *new; |
| u32 sid = 0, ptsid; |
| int error; |
| char *str = value; |
| |
| if (current != p) { |
| /* SELinux only allows a process to change its own |
| security attributes. */ |
| return -EACCES; |
| } |
| |
| /* |
| * Basic control over ability to set these attributes at all. |
| * current == p, but we'll pass them separately in case the |
| * above restriction is ever removed. |
| */ |
| if (!strcmp(name, "exec")) |
| error = current_has_perm(p, PROCESS__SETEXEC); |
| else if (!strcmp(name, "fscreate")) |
| error = current_has_perm(p, PROCESS__SETFSCREATE); |
| else if (!strcmp(name, "keycreate")) |
| error = current_has_perm(p, PROCESS__SETKEYCREATE); |
| else if (!strcmp(name, "sockcreate")) |
| error = current_has_perm(p, PROCESS__SETSOCKCREATE); |
| else if (!strcmp(name, "current")) |
| error = current_has_perm(p, PROCESS__SETCURRENT); |
| else |
| error = -EINVAL; |
| if (error) |
| return error; |
| |
| /* Obtain a SID for the context, if one was specified. */ |
| if (size && str[1] && str[1] != '\n') { |
| if (str[size-1] == '\n') { |
| str[size-1] = 0; |
| size--; |
| } |
| error = security_context_to_sid(value, size, &sid); |
| if (error == -EINVAL && !strcmp(name, "fscreate")) { |
| if (!capable(CAP_MAC_ADMIN)) |
| return error; |
| error = security_context_to_sid_force(value, size, |
| &sid); |
| } |
| if (error) |
| return error; |
| } |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| |
| /* Permission checking based on the specified context is |
| performed during the actual operation (execve, |
| open/mkdir/...), when we know the full context of the |
| operation. See selinux_bprm_set_creds for the execve |
| checks and may_create for the file creation checks. The |
| operation will then fail if the context is not permitted. */ |
| tsec = new->security; |
| if (!strcmp(name, "exec")) { |
| tsec->exec_sid = sid; |
| } else if (!strcmp(name, "fscreate")) { |
| tsec->create_sid = sid; |
| } else if (!strcmp(name, "keycreate")) { |
| error = may_create_key(sid, p); |
| if (error) |
| goto abort_change; |
| tsec->keycreate_sid = sid; |
| } else if (!strcmp(name, "sockcreate")) { |
| tsec->sockcreate_sid = sid; |
| } else if (!strcmp(name, "current")) { |
| error = -EINVAL; |
| if (sid == 0) |
| goto abort_change; |
| |
| /* Only allow single threaded processes to change context */ |
| error = -EPERM; |
| if (!current_is_single_threaded()) { |
| error = security_bounded_transition(tsec->sid, sid); |
| if (error) |
| goto abort_change; |
| } |
| |
| /* Check permissions for the transition. */ |
| error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, |
| PROCESS__DYNTRANSITION, NULL); |
| if (error) |
| goto abort_change; |
| |
| /* Check for ptracing, and update the task SID if ok. |
| Otherwise, leave SID unchanged and fail. */ |
| ptsid = 0; |
| task_lock(p); |
| tracer = tracehook_tracer_task(p); |
| if (tracer) |
| ptsid = task_sid(tracer); |
| task_unlock(p); |
| |
| if (tracer) { |
| error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, |
| PROCESS__PTRACE, NULL); |
| if (error) |
| goto abort_change; |
| } |
| |
| tsec->sid = sid; |
| } else { |
| error = -EINVAL; |
| goto abort_change; |
| } |
| |
| commit_creds(new); |
| return size; |
| |
| abort_change: |
| abort_creds(new); |
| return error; |
| } |
| |
| static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) |
| { |
| return security_sid_to_context(secid, secdata, seclen); |
| } |
| |
| static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) |
| { |
| return security_context_to_sid(secdata, seclen, secid); |
| } |
| |
| static void selinux_release_secctx(char *secdata, u32 seclen) |
| { |
| kfree(secdata); |
| } |
| |
| /* |
| * called with inode->i_mutex locked |
| */ |
| static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) |
| { |
| return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); |
| } |
| |
| /* |
| * called with inode->i_mutex locked |
| */ |
| static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) |
| { |
| return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); |
| } |
| |
| static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) |
| { |
| int len = 0; |
| len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, |
| ctx, true); |
| if (len < 0) |
| return len; |
| *ctxlen = len; |
| return 0; |
| } |
| #ifdef CONFIG_KEYS |
| |
| static int selinux_key_alloc(struct key *k, const struct cred *cred, |
| unsigned long flags) |
| { |
| const struct task_security_struct *tsec; |
| struct key_security_struct *ksec; |
| |
| ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); |
| if (!ksec) |
| return -ENOMEM; |
| |
| tsec = cred->security; |
| if (tsec->keycreate_sid) |
| ksec->sid = tsec->keycreate_sid; |
| else |
| ksec->sid = tsec->sid; |
| |
| k->security = ksec; |
| return 0; |
| } |
| |
| static void selinux_key_free(struct key *k) |
| { |
| struct key_security_struct *ksec = k->security; |
| |
| k->security = NULL; |
| kfree(ksec); |
| } |
| |
| static int selinux_key_permission(key_ref_t key_ref, |
| const struct cred *cred, |
| key_perm_t perm) |
| { |
| struct key *key; |
| struct key_security_struct *ksec; |
| u32 sid; |
| |
| /* if no specific permissions are requested, we skip the |
| permission check. No serious, additional covert channels |
| appear to be created. */ |
| if (perm == 0) |
| return 0; |
| |
| sid = cred_sid(cred); |
| |
| key = key_ref_to_ptr(key_ref); |
| ksec = key->security; |
| |
| return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); |
| } |
| |
| static int selinux_key_getsecurity(struct key *key, char **_buffer) |
| { |
| struct key_security_struct *ksec = key->security; |
| char *context = NULL; |
| unsigned len; |
| int rc; |
| |
| rc = security_sid_to_context(ksec->sid, &context, &len); |
| if (!rc) |
| rc = len; |
| *_buffer = context; |
| return rc; |
| } |
| |
| #endif |
| |
| static struct security_operations selinux_ops = { |
| .name = "selinux", |
| |
| .ptrace_access_check = selinux_ptrace_access_check, |
| .ptrace_traceme = selinux_ptrace_traceme, |
| .capget = selinux_capget, |
| .capset = selinux_capset, |
| .sysctl = selinux_sysctl, |
| .capable = selinux_capable, |
| .quotactl = selinux_quotactl, |
| .quota_on = selinux_quota_on, |
| .syslog = selinux_syslog, |
| .vm_enough_memory = selinux_vm_enough_memory, |
| |
| .netlink_send = selinux_netlink_send, |
| .netlink_recv = selinux_netlink_recv, |
| |
| .bprm_set_creds = selinux_bprm_set_creds, |
| .bprm_committing_creds = selinux_bprm_committing_creds, |
| .bprm_committed_creds = selinux_bprm_committed_creds, |
| .bprm_secureexec = selinux_bprm_secureexec, |
| |
| .sb_alloc_security = selinux_sb_alloc_security, |
| .sb_free_security = selinux_sb_free_security, |
| .sb_copy_data = selinux_sb_copy_data, |
| .sb_kern_mount = selinux_sb_kern_mount, |
| .sb_show_options = selinux_sb_show_options, |
| .sb_statfs = selinux_sb_statfs, |
| .sb_mount = selinux_mount, |
| .sb_umount = selinux_umount, |
| .sb_set_mnt_opts = selinux_set_mnt_opts, |
| .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, |
| .sb_parse_opts_str = selinux_parse_opts_str, |
| |
| |
| .inode_alloc_security = selinux_inode_alloc_security, |
| .inode_free_security = selinux_inode_free_security, |
| .inode_init_security = selinux_inode_init_security, |
| .inode_create = selinux_inode_create, |
| .inode_link = selinux_inode_link, |
| .inode_unlink = selinux_inode_unlink, |
| .inode_symlink = selinux_inode_symlink, |
| .inode_mkdir = selinux_inode_mkdir, |
| .inode_rmdir = selinux_inode_rmdir, |
| .inode_mknod = selinux_inode_mknod, |
| .inode_rename = selinux_inode_rename, |
| .inode_readlink = selinux_inode_readlink, |
| .inode_follow_link = selinux_inode_follow_link, |
| .inode_permission = selinux_inode_permission, |
| .inode_setattr = selinux_inode_setattr, |
| .inode_getattr = selinux_inode_getattr, |
| .inode_setxattr = selinux_inode_setxattr, |
| .inode_post_setxattr = selinux_inode_post_setxattr, |
| .inode_getxattr = selinux_inode_getxattr, |
| .inode_listxattr = selinux_inode_listxattr, |
| .inode_removexattr = selinux_inode_removexattr, |
| .inode_getsecurity = selinux_inode_getsecurity, |
| .inode_setsecurity = selinux_inode_setsecurity, |
| .inode_listsecurity = selinux_inode_listsecurity, |
| .inode_getsecid = selinux_inode_getsecid, |
| |
| .file_permission = selinux_file_permission, |
| .file_alloc_security = selinux_file_alloc_security, |
| .file_free_security = selinux_file_free_security, |
| .file_ioctl = selinux_file_ioctl, |
| .file_mmap = selinux_file_mmap, |
| .file_mprotect = selinux_file_mprotect, |
| .file_lock = selinux_file_lock, |
| .file_fcntl = selinux_file_fcntl, |
| .file_set_fowner = selinux_file_set_fowner, |
| .file_send_sigiotask = selinux_file_send_sigiotask, |
| .file_receive = selinux_file_receive, |
| |
| .dentry_open = selinux_dentry_open, |
| |
| .task_create = selinux_task_create, |
| .cred_alloc_blank = selinux_cred_alloc_blank, |
| .cred_free = selinux_cred_free, |
| .cred_prepare = selinux_cred_prepare, |
| .cred_transfer = selinux_cred_transfer, |
| .kernel_act_as = selinux_kernel_act_as, |
| .kernel_create_files_as = selinux_kernel_create_files_as, |
| .kernel_module_request = selinux_kernel_module_request, |
| .task_setpgid = selinux_task_setpgid, |
| .task_getpgid = selinux_task_getpgid, |
| .task_getsid = selinux_task_getsid, |
| .task_getsecid = selinux_task_getsecid, |
| .task_setnice = selinux_task_setnice, |
| .task_setioprio = selinux_task_setioprio, |
| .task_getioprio = selinux_task_getioprio, |
| .task_setrlimit = selinux_task_setrlimit, |
| .task_setscheduler = selinux_task_setscheduler, |
| .task_getscheduler = selinux_task_getscheduler, |
| .task_movememory = selinux_task_movememory, |
| .task_kill = selinux_task_kill, |
| .task_wait = selinux_task_wait, |
| .task_to_inode = selinux_task_to_inode, |
| |
| .ipc_permission = selinux_ipc_permission, |
| .ipc_getsecid = selinux_ipc_getsecid, |
| |
| .msg_msg_alloc_security = selinux_msg_msg_alloc_security, |
| .msg_msg_free_security = selinux_msg_msg_free_security, |
| |
| .msg_queue_alloc_security = selinux_msg_queue_alloc_security, |
| .msg_queue_free_security = selinux_msg_queue_free_security, |
| .msg_queue_associate = selinux_msg_queue_associate, |
| .msg_queue_msgctl = selinux_msg_queue_msgctl, |
| .msg_queue_msgsnd = selinux_msg_queue_msgsnd, |
| .msg_queue_msgrcv = selinux_msg_queue_msgrcv, |
| |
| .shm_alloc_security = selinux_shm_alloc_security, |
| .shm_free_security = selinux_shm_free_security, |
| .shm_associate = selinux_shm_associate, |
| .shm_shmctl = selinux_shm_shmctl, |
| .shm_shmat = selinux_shm_shmat, |
| |
| .sem_alloc_security = selinux_sem_alloc_security, |
| .sem_free_security = selinux_sem_free_security, |
| .sem_associate = selinux_sem_associate, |
| .sem_semctl = selinux_sem_semctl, |
| .sem_semop = selinux_sem_semop, |
| |
| .d_instantiate = selinux_d_instantiate, |
| |
| .getprocattr = selinux_getprocattr, |
| .setprocattr = selinux_setprocattr, |
| |
| .secid_to_secctx = selinux_secid_to_secctx, |
| .secctx_to_secid = selinux_secctx_to_secid, |
| .release_secctx = selinux_release_secctx, |
| .inode_notifysecctx = selinux_inode_notifysecctx, |
| .inode_setsecctx = selinux_inode_setsecctx, |
| .inode_getsecctx = selinux_inode_getsecctx, |
| |
| .unix_stream_connect = selinux_socket_unix_stream_connect, |
| .unix_may_send = selinux_socket_unix_may_send, |
| |
| .socket_create = selinux_socket_create, |
| .socket_post_create = selinux_socket_post_create, |
| .socket_bind = selinux_socket_bind, |
| .socket_connect = selinux_socket_connect, |
| .socket_listen = selinux_socket_listen, |
| .socket_accept = selinux_socket_accept, |
| .socket_sendmsg = selinux_socket_sendmsg, |
| .socket_recvmsg = selinux_socket_recvmsg, |
| .socket_getsockname = selinux_socket_getsockname, |
| .socket_getpeername = selinux_socket_getpeername, |
| .socket_getsockopt = selinux_socket_getsockopt, |
| .socket_setsockopt = selinux_socket_setsockopt, |
| .socket_shutdown = selinux_socket_shutdown, |
| .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, |
| .socket_getpeersec_stream = selinux_socket_getpeersec_stream, |
| .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, |
| .sk_alloc_security = selinux_sk_alloc_security, |
| .sk_free_security = selinux_sk_free_security, |
| .sk_clone_security = selinux_sk_clone_security, |
| .sk_getsecid = selinux_sk_getsecid, |
| .sock_graft = selinux_sock_graft, |
| .inet_conn_request = selinux_inet_conn_request, |
| .inet_csk_clone = selinux_inet_csk_clone, |
| .inet_conn_established = selinux_inet_conn_established, |
| .secmark_relabel_packet = selinux_secmark_relabel_packet, |
| .secmark_refcount_inc = selinux_secmark_refcount_inc, |
| .secmark_refcount_dec = selinux_secmark_refcount_dec, |
| .req_classify_flow = selinux_req_classify_flow, |
| .tun_dev_create = selinux_tun_dev_create, |
| .tun_dev_post_create = selinux_tun_dev_post_create, |
| .tun_dev_attach = selinux_tun_dev_attach, |
| |
| #ifdef CONFIG_SECURITY_NETWORK_XFRM |
| .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, |
| .xfrm_policy_clone_security = selinux_xfrm_policy_clone, |
| .xfrm_policy_free_security = selinux_xfrm_policy_free, |
| .xfrm_policy_delete_security = selinux_xfrm_policy_delete, |
| .xfrm_state_alloc_security = selinux_xfrm_state_alloc, |
| .xfrm_state_free_security = selinux_xfrm_state_free, |
| .xfrm_state_delete_security = selinux_xfrm_state_delete, |
| .xfrm_policy_lookup = selinux_xfrm_policy_lookup, |
| .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, |
| .xfrm_decode_session = selinux_xfrm_decode_session, |
| #endif |
| |
| #ifdef CONFIG_KEYS |
| .key_alloc = selinux_key_alloc, |
| .key_free = selinux_key_free, |
| .key_permission = selinux_key_permission, |
| .key_getsecurity = selinux_key_getsecurity, |
| #endif |
| |
| #ifdef CONFIG_AUDIT |
| .audit_rule_init = selinux_audit_rule_init, |
| .audit_rule_known = selinux_audit_rule_known, |
| .audit_rule_match = selinux_audit_rule_match, |
| .audit_rule_free = selinux_audit_rule_free, |
| #endif |
| }; |
| |
| static __init int selinux_init(void) |
| { |
| if (!security_module_enable(&selinux_ops)) { |
| selinux_enabled = 0; |
| return 0; |
| } |
| |
| if (!selinux_enabled) { |
| printk(KERN_INFO "SELinux: Disabled at boot.\n"); |
| return 0; |
| } |
| |
| printk(KERN_INFO "SELinux: Initializing.\n"); |
| |
| /* Set the security state for the initial task. */ |
| cred_init_security(); |
| |
| default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); |
| |
| sel_inode_cache = kmem_cache_create("selinux_inode_security", |
| sizeof(struct inode_security_struct), |
| 0, SLAB_PANIC, NULL); |
| avc_init(); |
| |
| if (register_security(&selinux_ops)) |
| panic("SELinux: Unable to register with kernel.\n"); |
| |
| if (selinux_enforcing) |
| printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); |
| else |
| printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); |
| |
| return 0; |
| } |
| |
| static void delayed_superblock_init(struct super_block *sb, void *unused) |
| { |
| superblock_doinit(sb, NULL); |
| } |
| |
| void selinux_complete_init(void) |
| { |
| printk(KERN_DEBUG "SELinux: Completing initialization.\n"); |
| |
| /* Set up any superblocks initialized prior to the policy load. */ |
| printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); |
| iterate_supers(delayed_superblock_init, NULL); |
| } |
| |
| /* SELinux requires early initialization in order to label |
| all processes and objects when they are created. */ |
| security_initcall(selinux_init); |
| |
| #if defined(CONFIG_NETFILTER) |
| |
| static struct nf_hook_ops selinux_ipv4_ops[] = { |
| { |
| .hook = selinux_ipv4_postroute, |
| .owner = THIS_MODULE, |
| .pf = PF_INET, |
| .hooknum = NF_INET_POST_ROUTING, |
| .priority = NF_IP_PRI_SELINUX_LAST, |
| }, |
| { |
| .hook = selinux_ipv4_forward, |
| .owner = THIS_MODULE, |
| .pf = PF_INET, |
| .hooknum = NF_INET_FORWARD, |
| .priority = NF_IP_PRI_SELINUX_FIRST, |
| }, |
| { |
| .hook = selinux_ipv4_output, |
| .owner = THIS_MODULE, |
| .pf = PF_INET, |
| .hooknum = NF_INET_LOCAL_OUT, |
| .priority = NF_IP_PRI_SELINUX_FIRST, |
| } |
| }; |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| |
| static struct nf_hook_ops selinux_ipv6_ops[] = { |
| { |
| .hook = selinux_ipv6_postroute, |
| .owner = THIS_MODULE, |
| .pf = PF_INET6, |
| .hooknum = NF_INET_POST_ROUTING, |
| .priority = NF_IP6_PRI_SELINUX_LAST, |
| }, |
| { |
| .hook = selinux_ipv6_forward, |
| .owner = THIS_MODULE, |
| .pf = PF_INET6, |
| .hooknum = NF_INET_FORWARD, |
| .priority = NF_IP6_PRI_SELINUX_FIRST, |
| } |
| }; |
| |
| #endif /* IPV6 */ |
| |
| static int __init selinux_nf_ip_init(void) |
| { |
| int err = 0; |
| |
| if (!selinux_enabled) |
| goto out; |
| |
| printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); |
| |
| err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); |
| if (err) |
| panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); |
| if (err) |
| panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); |
| #endif /* IPV6 */ |
| |
| out: |
| return err; |
| } |
| |
| __initcall(selinux_nf_ip_init); |
| |
| #ifdef CONFIG_SECURITY_SELINUX_DISABLE |
| static void selinux_nf_ip_exit(void) |
| { |
| printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); |
| |
| nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); |
| #endif /* IPV6 */ |
| } |
| #endif |
| |
| #else /* CONFIG_NETFILTER */ |
| |
| #ifdef CONFIG_SECURITY_SELINUX_DISABLE |
| #define selinux_nf_ip_exit() |
| #endif |
| |
| #endif /* CONFIG_NETFILTER */ |
| |
| #ifdef CONFIG_SECURITY_SELINUX_DISABLE |
| static int selinux_disabled; |
| |
| int selinux_disable(void) |
| { |
| extern void exit_sel_fs(void); |
| |
| if (ss_initialized) { |
| /* Not permitted after initial policy load. */ |
| return -EINVAL; |
| } |
| |
| if (selinux_disabled) { |
| /* Only do this once. */ |
| return -EINVAL; |
| } |
| |
| printk(KERN_INFO "SELinux: Disabled at runtime.\n"); |
| |
| selinux_disabled = 1; |
| selinux_enabled = 0; |
| |
| reset_security_ops(); |
| |
| /* Try to destroy the avc node cache */ |
| avc_disable(); |
| |
| /* Unregister netfilter hooks. */ |
| selinux_nf_ip_exit(); |
| |
| /* Unregister selinuxfs. */ |
| exit_sel_fs(); |
| |
| return 0; |
| } |
| #endif |