blob: a6eaa42fb66980c4fa3596249b30e0cd81c82f0c [file] [log] [blame]
/*
* 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/connector.h>
#include <linux/crypto.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/string.h>
#include <linux/in.h>
#include "netfs.h"
/*
* Global configuration list.
* Each client can be asked to get one of them.
*
* Allows to provide remote server address (ipv4/v6/whatever), port
* and so on via kernel connector.
*/
static struct cb_id pohmelfs_cn_id = {.idx = POHMELFS_CN_IDX, .val = POHMELFS_CN_VAL};
static LIST_HEAD(pohmelfs_config_list);
static DEFINE_MUTEX(pohmelfs_config_lock);
static inline int pohmelfs_config_eql(struct pohmelfs_ctl *sc, struct pohmelfs_ctl *ctl)
{
if (sc->idx == ctl->idx && sc->type == ctl->type &&
sc->proto == ctl->proto &&
sc->addrlen == ctl->addrlen &&
!memcmp(&sc->addr, &ctl->addr, ctl->addrlen))
return 1;
return 0;
}
static struct pohmelfs_config_group *pohmelfs_find_config_group(unsigned int idx)
{
struct pohmelfs_config_group *g, *group = NULL;
list_for_each_entry(g, &pohmelfs_config_list, group_entry) {
if (g->idx == idx) {
group = g;
break;
}
}
return group;
}
static struct pohmelfs_config_group *pohmelfs_find_create_config_group(unsigned int idx)
{
struct pohmelfs_config_group *g;
g = pohmelfs_find_config_group(idx);
if (g)
return g;
g = kzalloc(sizeof(struct pohmelfs_config_group), GFP_KERNEL);
if (!g)
return NULL;
INIT_LIST_HEAD(&g->config_list);
g->idx = idx;
g->num_entry = 0;
list_add_tail(&g->group_entry, &pohmelfs_config_list);
return g;
}
static inline void pohmelfs_insert_config_entry(struct pohmelfs_sb *psb, struct pohmelfs_config *dst)
{
struct pohmelfs_config *tmp;
INIT_LIST_HEAD(&dst->config_entry);
list_for_each_entry(tmp, &psb->state_list, config_entry) {
if (dst->state.ctl.prio > tmp->state.ctl.prio)
list_add_tail(&dst->config_entry, &tmp->config_entry);
}
if (list_empty(&dst->config_entry))
list_add_tail(&dst->config_entry, &psb->state_list);
}
static int pohmelfs_move_config_entry(struct pohmelfs_sb *psb,
struct pohmelfs_config *dst, struct pohmelfs_config *new)
{
if ((dst->state.ctl.prio == new->state.ctl.prio) &&
(dst->state.ctl.perm == new->state.ctl.perm))
return 0;
dprintk("%s: dst: prio: %d, perm: %x, new: prio: %d, perm: %d.\n",
__func__, dst->state.ctl.prio, dst->state.ctl.perm,
new->state.ctl.prio, new->state.ctl.perm);
dst->state.ctl.prio = new->state.ctl.prio;
dst->state.ctl.perm = new->state.ctl.perm;
list_del_init(&dst->config_entry);
pohmelfs_insert_config_entry(psb, dst);
return 0;
}
/*
* pohmelfs_copy_config() is used to copy new state configs from the
* config group (controlled by the netlink messages) into the superblock.
* This happens either at startup time where no transactions can access
* the list of the configs (and thus list of the network states), or at
* run-time, where it is protected by the psb->state_lock.
*/
int pohmelfs_copy_config(struct pohmelfs_sb *psb)
{
struct pohmelfs_config_group *g;
struct pohmelfs_config *c, *dst;
int err = -ENODEV;
mutex_lock(&pohmelfs_config_lock);
g = pohmelfs_find_config_group(psb->idx);
if (!g)
goto out_unlock;
/*
* Run over all entries in given config group and try to crate and
* initialize those, which do not exist in superblock list.
* Skip all existing entries.
*/
list_for_each_entry(c, &g->config_list, config_entry) {
err = 0;
list_for_each_entry(dst, &psb->state_list, config_entry) {
if (pohmelfs_config_eql(&dst->state.ctl, &c->state.ctl)) {
err = pohmelfs_move_config_entry(psb, dst, c);
if (!err)
err = -EEXIST;
break;
}
}
if (err)
continue;
dst = kzalloc(sizeof(struct pohmelfs_config), GFP_KERNEL);
if (!dst) {
err = -ENOMEM;
break;
}
memcpy(&dst->state.ctl, &c->state.ctl, sizeof(struct pohmelfs_ctl));
pohmelfs_insert_config_entry(psb, dst);
err = pohmelfs_state_init_one(psb, dst);
if (err) {
list_del(&dst->config_entry);
kfree(dst);
}
err = 0;
}
out_unlock:
mutex_unlock(&pohmelfs_config_lock);
return err;
}
int pohmelfs_copy_crypto(struct pohmelfs_sb *psb)
{
struct pohmelfs_config_group *g;
int err = -ENOENT;
mutex_lock(&pohmelfs_config_lock);
g = pohmelfs_find_config_group(psb->idx);
if (!g)
goto err_out_exit;
if (g->hash_string) {
err = -ENOMEM;
psb->hash_string = kstrdup(g->hash_string, GFP_KERNEL);
if (!psb->hash_string)
goto err_out_exit;
psb->hash_strlen = g->hash_strlen;
}
if (g->cipher_string) {
psb->cipher_string = kstrdup(g->cipher_string, GFP_KERNEL);
if (!psb->cipher_string)
goto err_out_free_hash_string;
psb->cipher_strlen = g->cipher_strlen;
}
if (g->hash_keysize) {
psb->hash_key = kmalloc(g->hash_keysize, GFP_KERNEL);
if (!psb->hash_key)
goto err_out_free_cipher_string;
memcpy(psb->hash_key, g->hash_key, g->hash_keysize);
psb->hash_keysize = g->hash_keysize;
}
if (g->cipher_keysize) {
psb->cipher_key = kmalloc(g->cipher_keysize, GFP_KERNEL);
if (!psb->cipher_key)
goto err_out_free_hash;
memcpy(psb->cipher_key, g->cipher_key, g->cipher_keysize);
psb->cipher_keysize = g->cipher_keysize;
}
mutex_unlock(&pohmelfs_config_lock);
return 0;
err_out_free_hash:
kfree(psb->hash_key);
err_out_free_cipher_string:
kfree(psb->cipher_string);
err_out_free_hash_string:
kfree(psb->hash_string);
err_out_exit:
mutex_unlock(&pohmelfs_config_lock);
return err;
}
static int pohmelfs_send_reply(int err, int msg_num, int action, struct cn_msg *msg, struct pohmelfs_ctl *ctl)
{
struct pohmelfs_cn_ack *ack;
ack = kmalloc(sizeof(struct pohmelfs_cn_ack), GFP_KERNEL);
if (!ack)
return -ENOMEM;
memset(ack, 0, sizeof(struct pohmelfs_cn_ack));
memcpy(&ack->msg, msg, sizeof(struct cn_msg));
if (action == POHMELFS_CTLINFO_ACK)
memcpy(&ack->ctl, ctl, sizeof(struct pohmelfs_ctl));
ack->msg.len = sizeof(struct pohmelfs_cn_ack) - sizeof(struct cn_msg);
ack->msg.ack = msg->ack + 1;
ack->error = err;
ack->msg_num = msg_num;
cn_netlink_send(&ack->msg, 0, GFP_KERNEL);
kfree(ack);
return 0;
}
static int pohmelfs_cn_disp(struct cn_msg *msg)
{
struct pohmelfs_config_group *g;
struct pohmelfs_ctl *ctl = (struct pohmelfs_ctl *)msg->data;
struct pohmelfs_config *c, *tmp;
int err = 0, i = 1;
if (msg->len != sizeof(struct pohmelfs_ctl))
return -EBADMSG;
mutex_lock(&pohmelfs_config_lock);
g = pohmelfs_find_config_group(ctl->idx);
if (!g) {
pohmelfs_send_reply(err, 0, POHMELFS_NOINFO_ACK, msg, NULL);
goto out_unlock;
}
list_for_each_entry_safe(c, tmp, &g->config_list, config_entry) {
struct pohmelfs_ctl *sc = &c->state.ctl;
if (pohmelfs_send_reply(err, g->num_entry - i, POHMELFS_CTLINFO_ACK, msg, sc)) {
err = -ENOMEM;
goto out_unlock;
}
i += 1;
}
out_unlock:
mutex_unlock(&pohmelfs_config_lock);
return err;
}
static int pohmelfs_modify_config(struct pohmelfs_ctl *old, struct pohmelfs_ctl *new)
{
old->perm = new->perm;
old->prio = new->prio;
return 0;
}
static int pohmelfs_cn_ctl(struct cn_msg *msg, int action)
{
struct pohmelfs_config_group *g;
struct pohmelfs_ctl *ctl = (struct pohmelfs_ctl *)msg->data;
struct pohmelfs_config *c, *tmp;
int err = 0;
if (msg->len != sizeof(struct pohmelfs_ctl))
return -EBADMSG;
mutex_lock(&pohmelfs_config_lock);
g = pohmelfs_find_create_config_group(ctl->idx);
if (!g) {
err = -ENOMEM;
goto out_unlock;
}
list_for_each_entry_safe(c, tmp, &g->config_list, config_entry) {
struct pohmelfs_ctl *sc = &c->state.ctl;
if (pohmelfs_config_eql(sc, ctl)) {
if (action == POHMELFS_FLAGS_ADD) {
err = -EEXIST;
goto out_unlock;
} else if (action == POHMELFS_FLAGS_DEL) {
list_del(&c->config_entry);
g->num_entry--;
kfree(c);
goto out_unlock;
} else if (action == POHMELFS_FLAGS_MODIFY) {
err = pohmelfs_modify_config(sc, ctl);
goto out_unlock;
} else {
err = -EEXIST;
goto out_unlock;
}
}
}
if (action == POHMELFS_FLAGS_DEL) {
err = -EBADMSG;
goto out_unlock;
}
c = kzalloc(sizeof(struct pohmelfs_config), GFP_KERNEL);
if (!c) {
err = -ENOMEM;
goto out_unlock;
}
memcpy(&c->state.ctl, ctl, sizeof(struct pohmelfs_ctl));
g->num_entry++;
list_add_tail(&c->config_entry, &g->config_list);
out_unlock:
mutex_unlock(&pohmelfs_config_lock);
if (pohmelfs_send_reply(err, 0, POHMELFS_NOINFO_ACK, msg, NULL))
err = -ENOMEM;
return err;
}
static int pohmelfs_crypto_hash_init(struct pohmelfs_config_group *g, struct pohmelfs_crypto *c)
{
char *algo = (char *)c->data;
u8 *key = (u8 *)(algo + c->strlen);
if (g->hash_string)
return -EEXIST;
g->hash_string = kstrdup(algo, GFP_KERNEL);
if (!g->hash_string)
return -ENOMEM;
g->hash_strlen = c->strlen;
g->hash_keysize = c->keysize;
g->hash_key = kmalloc(c->keysize, GFP_KERNEL);
if (!g->hash_key) {
kfree(g->hash_string);
return -ENOMEM;
}
memcpy(g->hash_key, key, c->keysize);
return 0;
}
static int pohmelfs_crypto_cipher_init(struct pohmelfs_config_group *g, struct pohmelfs_crypto *c)
{
char *algo = (char *)c->data;
u8 *key = (u8 *)(algo + c->strlen);
if (g->cipher_string)
return -EEXIST;
g->cipher_string = kstrdup(algo, GFP_KERNEL);
if (!g->cipher_string)
return -ENOMEM;
g->cipher_strlen = c->strlen;
g->cipher_keysize = c->keysize;
g->cipher_key = kmalloc(c->keysize, GFP_KERNEL);
if (!g->cipher_key) {
kfree(g->cipher_string);
return -ENOMEM;
}
memcpy(g->cipher_key, key, c->keysize);
return 0;
}
static int pohmelfs_cn_crypto(struct cn_msg *msg)
{
struct pohmelfs_crypto *crypto = (struct pohmelfs_crypto *)msg->data;
struct pohmelfs_config_group *g;
int err = 0;
dprintk("%s: idx: %u, strlen: %u, type: %u, keysize: %u, algo: %s.\n",
__func__, crypto->idx, crypto->strlen, crypto->type,
crypto->keysize, (char *)crypto->data);
mutex_lock(&pohmelfs_config_lock);
g = pohmelfs_find_create_config_group(crypto->idx);
if (!g) {
err = -ENOMEM;
goto out_unlock;
}
switch (crypto->type) {
case POHMELFS_CRYPTO_HASH:
err = pohmelfs_crypto_hash_init(g, crypto);
break;
case POHMELFS_CRYPTO_CIPHER:
err = pohmelfs_crypto_cipher_init(g, crypto);
break;
default:
err = -ENOTSUPP;
break;
}
out_unlock:
mutex_unlock(&pohmelfs_config_lock);
if (pohmelfs_send_reply(err, 0, POHMELFS_NOINFO_ACK, msg, NULL))
err = -ENOMEM;
return err;
}
static void pohmelfs_cn_callback(void *data)
{
struct cn_msg *msg = data;
int err;
switch (msg->flags) {
case POHMELFS_FLAGS_ADD:
case POHMELFS_FLAGS_DEL:
case POHMELFS_FLAGS_MODIFY:
err = pohmelfs_cn_ctl(msg, msg->flags);
break;
case POHMELFS_FLAGS_SHOW:
err = pohmelfs_cn_disp(msg);
break;
case POHMELFS_FLAGS_CRYPTO:
err = pohmelfs_cn_crypto(msg);
break;
default:
err = -ENOSYS;
break;
}
}
int pohmelfs_config_check(struct pohmelfs_config *config, int idx)
{
struct pohmelfs_ctl *ctl = &config->state.ctl;
struct pohmelfs_config *tmp;
int err = -ENOENT;
struct pohmelfs_ctl *sc;
struct pohmelfs_config_group *g;
mutex_lock(&pohmelfs_config_lock);
g = pohmelfs_find_config_group(ctl->idx);
if (g) {
list_for_each_entry(tmp, &g->config_list, config_entry) {
sc = &tmp->state.ctl;
if (pohmelfs_config_eql(sc, ctl)) {
err = 0;
break;
}
}
}
mutex_unlock(&pohmelfs_config_lock);
return err;
}
int __init pohmelfs_config_init(void)
{
return cn_add_callback(&pohmelfs_cn_id, "pohmelfs", pohmelfs_cn_callback);
}
void pohmelfs_config_exit(void)
{
struct pohmelfs_config *c, *tmp;
struct pohmelfs_config_group *g, *gtmp;
cn_del_callback(&pohmelfs_cn_id);
mutex_lock(&pohmelfs_config_lock);
list_for_each_entry_safe(g, gtmp, &pohmelfs_config_list, group_entry) {
list_for_each_entry_safe(c, tmp, &g->config_list, config_entry) {
list_del(&c->config_entry);
kfree(c);
}
list_del(&g->group_entry);
if (g->hash_string)
kfree(g->hash_string);
if (g->cipher_string)
kfree(g->cipher_string);
kfree(g);
}
mutex_unlock(&pohmelfs_config_lock);
}