Add --dhcp-hostsdir config option.
diff --git a/CHANGELOG b/CHANGELOG
index bbd7e66..0076b55 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -53,6 +53,11 @@
Cope with multiple interfaces with the same link-local
address. (IPv6 addresses are scoped, so this is allowed.)
Thanks to Cory Benfield for help with this.
+
+ Add --dhcp-hostsdir. This allows addition of new host
+ configurations to a running dnsmasq instance much more
+ cheaply than having dnsmasq re-read all its existing
+ configuration each time.
version 2.72
diff --git a/man/dnsmasq.8 b/man/dnsmasq.8
index 5cfa355..005b5cc 100644
--- a/man/dnsmasq.8
+++ b/man/dnsmasq.8
@@ -977,6 +977,15 @@
using this option is the same as for --dhcp-hostsfile: the
dhcp-optsfile will be re-read when dnsmasq receives SIGHUP. Note that
it is possible to encode the information in a
+.TP
+.B --dhcp-hostsdir=<path>
+This is exactly equivalent to dhcp-hostfile, except for the following. The path MUST be a
+directory, and not an individual file. Changed or new files within
+the directory are read automatically, without the need to send SIGHUP.
+If a file is deleted for changed after it has been read by dnsmasq, then the
+host record it contained will remain until dnsmasq recieves a SIGHUP, or
+is restarted; ie host records are only added dynamically.
+.TP
.B --dhcp-boot
flag as DHCP options, using the options names bootfile-name,
server-ip-address and tftp-server. This allows these to be included
diff --git a/src/dnsmasq.c b/src/dnsmasq.c
index c0c0589..04cc982 100644
--- a/src/dnsmasq.c
+++ b/src/dnsmasq.c
@@ -142,6 +142,9 @@
set_option_bool(OPT_NOWILD);
reset_option_bool(OPT_CLEVERBIND);
}
+
+ if (daemon->inotify_hosts)
+ die(_("dhcp-hostsdir not supported on this platform"), NULL, EC_BADCONF);
#endif
if (option_bool(OPT_DNSSEC_VALID))
@@ -316,13 +319,16 @@
#ifdef HAVE_DNSSEC
blockdata_init();
#endif
+ }
#ifdef HAVE_LINUX_NETWORK
- if (!option_bool(OPT_NO_POLL))
- inotify_dnsmasq_init();
+ if ((!option_bool(OPT_NO_POLL) && daemon->port != 0) ||
+ daemon->dhcp || daemon->doing_dhcp6)
+ inotify_dnsmasq_init();
+ else
+ daemon->inotifyfd = -1;
#endif
- }
-
+
if (option_bool(OPT_DBUS))
#ifdef HAVE_DBUS
{
@@ -745,7 +751,7 @@
#endif
#ifdef HAVE_TFTP
- if (option_bool(OPT_TFTP))
+ if (option_bool(OPT_TFTP))
{
#ifdef FD_SETSIZE
if (FD_SETSIZE < (unsigned)max_fd)
@@ -870,7 +876,7 @@
#if defined(HAVE_LINUX_NETWORK)
FD_SET(daemon->netlinkfd, &rset);
bump_maxfd(daemon->netlinkfd, &maxfd);
- if (daemon->port != 0 && !option_bool(OPT_NO_POLL))
+ if (daemon->inotifyfd != -1)
{
FD_SET(daemon->inotifyfd, &rset);
bump_maxfd(daemon->inotifyfd, &maxfd);
@@ -943,8 +949,11 @@
#endif
#ifdef HAVE_LINUX_NETWORK
- if (daemon->port != 0 && !option_bool(OPT_NO_POLL) && FD_ISSET(daemon->inotifyfd, &rset) && inotify_check())
- poll_resolv(1, 1, now);
+ if (daemon->inotifyfd != -1 && FD_ISSET(daemon->inotifyfd, &rset) && inotify_check(now))
+ {
+ if (daemon->port != 0 && !option_bool(OPT_NO_POLL))
+ poll_resolv(1, 1, now);
+ }
#else
/* Check for changes to resolv files once per second max. */
/* Don't go silent for long periods if the clock goes backwards. */
@@ -1385,6 +1394,9 @@
if (option_bool(OPT_ETHERS))
dhcp_read_ethers();
reread_dhcp();
+#ifdef HAVE_LINUX_NETWORK
+ set_dhcp_inotify();
+#endif
dhcp_update_configs(daemon->dhcp_conf);
lease_update_from_configs();
lease_update_file(now);
diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index f8275e3..d841fdc 100644
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -550,13 +550,17 @@
#endif
};
-/* adn-hosts parms from command-line (also dhcp-hostsfile and dhcp-optsfile */
+/* adn-hosts parms from command-line (also dhcp-hostsfile and dhcp-optsfile and dhcp-hostsdir*/
#define AH_DIR 1
#define AH_INACTIVE 2
+#define AH_WD_DONE 4
struct hostsfile {
struct hostsfile *next;
int flags;
char *fname;
+#ifdef HAVE_LINUX_NETWORK
+ int wd; /* inotify watch descriptor */
+#endif
unsigned int index; /* matches to cache entries for logging */
};
@@ -961,7 +965,7 @@
int doing_ra, doing_dhcp6;
struct dhcp_netid_list *dhcp_ignore, *dhcp_ignore_names, *dhcp_gen_names;
struct dhcp_netid_list *force_broadcast, *bootp_dynamic;
- struct hostsfile *dhcp_hosts_file, *dhcp_opts_file;
+ struct hostsfile *dhcp_hosts_file, *dhcp_opts_file, *inotify_hosts;
int dhcp_max, tftp_max;
int dhcp_server_port, dhcp_client_port;
int start_tftp_port, end_tftp_port;
@@ -1197,7 +1201,7 @@
struct hostsfile *expand_filelist(struct hostsfile *list);
char *parse_server(char *arg, union mysockaddr *addr,
union mysockaddr *source_addr, char *interface, int *flags);
-
+int option_read_hostsfile(char *file);
/* forward.c */
void reply_query(int fd, int family, time_t now);
void receive_query(struct listener *listen, time_t now);
@@ -1486,5 +1490,8 @@
/* inotify.c */
#ifdef HAVE_LINUX_NETWORK
void inotify_dnsmasq_init();
-int inotify_check(void);
+int inotify_check(time_t now);
+# ifdef HAVE_DHCP
+void set_dhcp_inotify(void);
+# endif
#endif
diff --git a/src/inotify.c b/src/inotify.c
index 8373000..52a30d7 100644
--- a/src/inotify.c
+++ b/src/inotify.c
@@ -19,6 +19,11 @@
#include <sys/inotify.h>
+#ifdef HAVE_DHCP
+static void check_for_dhcp_inotify(struct inotify_event *in, time_t now);
+#endif
+
+
/* the strategy is to set a inotify on the directories containing
resolv files, for any files in the directory which are close-write
or moved into the directory.
@@ -40,8 +45,6 @@
struct resolvc *res;
inotify_buffer = safe_malloc(INOTIFY_SZ);
-
-
daemon->inotifyfd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
if (daemon->inotifyfd == -1)
@@ -66,6 +69,7 @@
{
*d = 0; /* make path just directory */
res->wd = inotify_add_watch(daemon->inotifyfd, path, IN_CLOSE_WRITE | IN_MOVED_TO);
+
res->file = d+1; /* pointer to filename */
*d = '/';
@@ -78,7 +82,7 @@
}
}
-int inotify_check(void)
+int inotify_check(time_t now)
{
int hit = 0;
@@ -101,13 +105,116 @@
for (res = daemon->resolv_files; res; res = res->next)
if (res->wd == in->wd && in->len != 0 && strcmp(res->file, in->name) == 0)
hit = 1;
+
+#ifdef HAVE_DHCP
+ if (daemon->dhcp || daemon->doing_dhcp6)
+ check_for_dhcp_inotify(in, now);
+#endif
}
}
-
return hit;
}
-#endif
+#ifdef HAVE_DHCP
+/* initialisation for dhcp-hostdir. Set inotify watch for each directory, and read pre-existing files */
+void set_dhcp_inotify(void)
+{
+ struct hostsfile *ah;
-
+ for (ah = daemon->inotify_hosts; ah; ah = ah->next)
+ {
+ DIR *dir_stream = NULL;
+ struct dirent *ent;
+ struct stat buf;
+
+ if (stat(ah->fname, &buf) == -1 || !(S_ISDIR(buf.st_mode)))
+ {
+ my_syslog(LOG_ERR, _("bad directory in dhcp-hostsdir %s"), ah->fname);
+ continue;
+ }
+
+ if (!(ah->flags & AH_WD_DONE))
+ {
+ ah->wd = inotify_add_watch(daemon->inotifyfd, ah->fname, IN_CLOSE_WRITE | IN_MOVED_TO);
+ ah->flags |= AH_WD_DONE;
+ }
+ /* Read contents of dir _after_ calling add_watch, in the ho[e of avoiding
+ a race which misses files being added as we start */
+ if (ah->wd == -1 || !(dir_stream = opendir(ah->fname)))
+ {
+ my_syslog(LOG_ERR, _("failed to create inotify for %s"), ah->fname);
+ continue;
+ }
+
+ while ((ent = readdir(dir_stream)))
+ {
+ size_t lendir = strlen(ah->fname);
+ size_t lenfile = strlen(ent->d_name);
+ char *path;
+
+ /* ignore emacs backups and dotfiles */
+ if (lenfile == 0 ||
+ ent->d_name[lenfile - 1] == '~' ||
+ (ent->d_name[0] == '#' && ent->d_name[lenfile - 1] == '#') ||
+ ent->d_name[0] == '.')
+ continue;
+
+ if ((path = whine_malloc(lendir + lenfile + 2)))
+ {
+ strcpy(path, ah->fname);
+ strcat(path, "/");
+ strcat(path, ent->d_name);
+
+ /* ignore non-regular files */
+ if (stat(path, &buf) != -1 && S_ISREG(buf.st_mode))
+ option_read_hostsfile(path);
+
+ free(path);
+ }
+ }
+ }
+}
+
+static void check_for_dhcp_inotify(struct inotify_event *in, time_t now)
+{
+ struct hostsfile *ah;
+
+ /* ignore emacs backups and dotfiles */
+ if (in->len == 0 ||
+ in->name[in->len - 1] == '~' ||
+ (in->name[0] == '#' && in->name[in->len - 1] == '#') ||
+ in->name[0] == '.')
+ return;
+
+ for (ah = daemon->inotify_hosts; ah; ah = ah->next)
+ if (ah->wd == in->wd)
+ {
+ size_t lendir = strlen(ah->fname);
+ char *path;
+
+ if ((path = whine_malloc(lendir + in->len + 2)))
+ {
+ strcpy(path, ah->fname);
+ strcat(path, "/");
+ strcat(path, in->name);
+
+ if (option_read_hostsfile(path))
+ {
+ /* Propogate the consequences of loading a new dhcp-host */
+ dhcp_update_configs(daemon->dhcp_conf);
+ lease_update_from_configs();
+ lease_update_file(now);
+ lease_update_dns(1);
+ }
+
+ free(path);
+ }
+
+ return;
+ }
+}
+
+#endif /* DHCP */
+
+#endif /* LINUX_NETWORK */
diff --git a/src/option.c b/src/option.c
index 8b99409..22e11c3 100644
--- a/src/option.c
+++ b/src/option.c
@@ -149,7 +149,7 @@
#define LOPT_LOOP_DETECT 337
#define LOPT_IGNORE_ADDR 338
#define LOPT_MINCTTL 339
-
+#define LOPT_DHCP_INOTIFY 340
#ifdef HAVE_GETOPT_LONG
static const struct option opts[] =
@@ -248,6 +248,7 @@
{ "interface-name", 1, 0, LOPT_INTNAME },
{ "dhcp-hostsfile", 1, 0, LOPT_DHCP_HOST },
{ "dhcp-optsfile", 1, 0, LOPT_DHCP_OPTS },
+ { "dhcp-hostsdir", 1, 0, LOPT_DHCP_INOTIFY },
{ "dhcp-no-override", 0, 0, LOPT_OVERRIDE },
{ "tftp-port-range", 1, 0, LOPT_TFTPPORTS },
{ "stop-dns-rebind", 0, 0, LOPT_REBIND },
@@ -336,6 +337,7 @@
{ 'G', ARG_DUP, "<hostspec>", gettext_noop("Set address or hostname for a specified machine."), NULL },
{ LOPT_DHCP_HOST, ARG_DUP, "<path>", gettext_noop("Read DHCP host specs from file."), NULL },
{ LOPT_DHCP_OPTS, ARG_DUP, "<path>", gettext_noop("Read DHCP option specs from file."), NULL },
+ { LOPT_DHCP_INOTIFY, ARG_DUP, "<path>", gettext_noop("Read DHCP host specs from a directory."), NULL },
{ LOPT_TAG_IF, ARG_DUP, "tag-expression", gettext_noop("Evaluate conditional tag expression."), NULL },
{ 'h', OPT_NO_HOSTS, NULL, gettext_noop("Do NOT load %s file."), HOSTSFILE },
{ 'H', ARG_DUP, "<path>", gettext_noop("Specify a hosts file to be read in addition to %s."), HOSTSFILE },
@@ -1710,8 +1712,9 @@
break;
#endif /* HAVE_DHCP */
- case LOPT_DHCP_HOST: /* --dhcp-hostfile */
+ case LOPT_DHCP_HOST: /* --dhcp-hostsfile */
case LOPT_DHCP_OPTS: /* --dhcp-optsfile */
+ case LOPT_DHCP_INOTIFY: /* dhcp-hostsdir */
case 'H': /* --addn-hosts */
{
struct hostsfile *new = opt_malloc(sizeof(struct hostsfile));
@@ -1734,6 +1737,12 @@
new->next = daemon->dhcp_opts_file;
daemon->dhcp_opts_file = new;
}
+ else if (option == LOPT_DHCP_INOTIFY)
+ {
+ new->next = daemon->inotify_hosts;
+ daemon->inotify_hosts = new;
+ }
+
break;
}
@@ -4042,6 +4051,13 @@
fclose(f);
}
+#ifdef HAVE_DHCP
+int option_read_hostsfile(char *file)
+{
+ return one_file(file, LOPT_BANK);
+}
+#endif
+
static int one_file(char *file, int hard_opt)
{
FILE *f;
@@ -4139,7 +4155,7 @@
/* don't read this as a file */
ah->flags |= AH_INACTIVE;
-
+
if (!(dir_stream = opendir(ah->fname)))
my_syslog(LOG_ERR, _("cannot access directory %s: %s"),
ah->fname, strerror(errno));
