diff options
author | Harald Welte <laforge@netfilter.org> | 2005-10-26 07:34:24 (GMT) |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@mandriva.com> | 2005-10-31 18:36:08 (GMT) |
commit | 6b7d31fcdda5938e5d3f1f8b0922cc25aa200dfc (patch) | |
tree | c44f46d7eab0ea138247018ba1e04da6df8ae9d4 /net/ipv6 | |
parent | 6ede2463c8d7ea949f8e7ef35243490c415ddc2f (diff) | |
download | linux-fsl-qoriq-6b7d31fcdda5938e5d3f1f8b0922cc25aa200dfc.tar.xz |
[NETFILTER]: Add "revision" support to arp_tables and ip6_tables
Like ip_tables already has it for some time, this adds support for
having multiple revisions for each match/target. We steal one byte from
the name in order to accomodate a 8 bit version number.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Diffstat (limited to 'net/ipv6')
-rw-r--r-- | net/ipv6/netfilter/ip6_tables.c | 298 | ||||
-rw-r--r-- | net/ipv6/netfilter/ip6t_MARK.c | 8 |
2 files changed, 192 insertions, 114 deletions
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 21deec2..7d49222 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -2,7 +2,7 @@ * Packet matching code. * * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling - * Copyright (C) 2000-2002 Netfilter core team <coreteam@netfilter.org> + * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org> * * 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 @@ -23,7 +23,6 @@ #include <linux/tcp.h> #include <linux/udp.h> #include <linux/icmpv6.h> -#include <net/ip.h> #include <net/ipv6.h> #include <asm/uaccess.h> #include <asm/semaphore.h> @@ -80,13 +79,12 @@ static DECLARE_MUTEX(ip6t_mutex); #define inline #endif -/* Locking is simple: we assume at worst case there will be one packet - in user context and one from bottom halves (or soft irq if Alexey's - softnet patch was applied). - +/* We keep a set of rules for each CPU, so we can avoid write-locking - them; doing a readlock_bh() stops packets coming through if we're - in user context. + them in the softirq when updating the counters and therefore + only need to read-lock in the softirq; doing a write_lock_bh() in user + context stops packets coming through and allows user context to read + the counters or update the rules. To be cache friendly on SMP, we arrange them like so: [ n-entries ] @@ -356,7 +354,7 @@ ip6t_do_table(struct sk_buff **pskb, struct ip6t_table *table, void *userdata) { - static const char nulldevname[IFNAMSIZ]; + static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); int offset = 0; unsigned int protoff = 0; int hotdrop = 0; @@ -369,7 +367,6 @@ ip6t_do_table(struct sk_buff **pskb, /* Initialization */ indev = in ? in->name : nulldevname; outdev = out ? out->name : nulldevname; - /* We handle fragments by dealing with the first fragment as * if it was a normal packet. All other fragments are treated * normally, except that they will NEVER match rules that ask @@ -497,75 +494,145 @@ ip6t_do_table(struct sk_buff **pskb, #endif } -/* If it succeeds, returns element and locks mutex */ -static inline void * -find_inlist_lock_noload(struct list_head *head, - const char *name, - int *error, - struct semaphore *mutex) +/* + * These are weird, but module loading must not be done with mutex + * held (since they will register), and we have to have a single + * function to use try_then_request_module(). + */ + +/* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ +static inline struct ip6t_table *find_table_lock(const char *name) { - void *ret; + struct ip6t_table *t; -#if 1 - duprintf("find_inlist: searching for `%s' in %s.\n", - name, head == &ip6t_target ? "ip6t_target" - : head == &ip6t_match ? "ip6t_match" - : head == &ip6t_tables ? "ip6t_tables" : "UNKNOWN"); -#endif + if (down_interruptible(&ip6t_mutex) != 0) + return ERR_PTR(-EINTR); - *error = down_interruptible(mutex); - if (*error != 0) - return NULL; + list_for_each_entry(t, &ip6t_tables, list) + if (strcmp(t->name, name) == 0 && try_module_get(t->me)) + return t; + up(&ip6t_mutex); + return NULL; +} + +/* Find match, grabs ref. Returns ERR_PTR() on error. */ +static inline struct ip6t_match *find_match(const char *name, u8 revision) +{ + struct ip6t_match *m; + int err = 0; - ret = list_named_find(head, name); - if (!ret) { - *error = -ENOENT; - up(mutex); + if (down_interruptible(&ip6t_mutex) != 0) + return ERR_PTR(-EINTR); + + list_for_each_entry(m, &ip6t_match, list) { + if (strcmp(m->name, name) == 0) { + if (m->revision == revision) { + if (try_module_get(m->me)) { + up(&ip6t_mutex); + return m; + } + } else + err = -EPROTOTYPE; /* Found something. */ + } } - return ret; + up(&ip6t_mutex); + return ERR_PTR(err); } -#ifndef CONFIG_KMOD -#define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m)) -#else -static void * -find_inlist_lock(struct list_head *head, - const char *name, - const char *prefix, - int *error, - struct semaphore *mutex) +/* Find target, grabs ref. Returns ERR_PTR() on error. */ +static inline struct ip6t_target *find_target(const char *name, u8 revision) { - void *ret; + struct ip6t_target *t; + int err = 0; - ret = find_inlist_lock_noload(head, name, error, mutex); - if (!ret) { - duprintf("find_inlist: loading `%s%s'.\n", prefix, name); - request_module("%s%s", prefix, name); - ret = find_inlist_lock_noload(head, name, error, mutex); + if (down_interruptible(&ip6t_mutex) != 0) + return ERR_PTR(-EINTR); + + list_for_each_entry(t, &ip6t_target, list) { + if (strcmp(t->name, name) == 0) { + if (t->revision == revision) { + if (try_module_get(t->me)) { + up(&ip6t_mutex); + return t; + } + } else + err = -EPROTOTYPE; /* Found something. */ + } } + up(&ip6t_mutex); + return ERR_PTR(err); +} - return ret; +struct ip6t_target *ip6t_find_target(const char *name, u8 revision) +{ + struct ip6t_target *target; + + target = try_then_request_module(find_target(name, revision), + "ip6t_%s", name); + if (IS_ERR(target) || !target) + return NULL; + return target; } -#endif -static inline struct ip6t_table * -ip6t_find_table_lock(const char *name, int *error, struct semaphore *mutex) +static int match_revfn(const char *name, u8 revision, int *bestp) { - return find_inlist_lock(&ip6t_tables, name, "ip6table_", error, mutex); + struct ip6t_match *m; + int have_rev = 0; + + list_for_each_entry(m, &ip6t_match, list) { + if (strcmp(m->name, name) == 0) { + if (m->revision > *bestp) + *bestp = m->revision; + if (m->revision == revision) + have_rev = 1; + } + } + return have_rev; } -static inline struct ip6t_match * -find_match_lock(const char *name, int *error, struct semaphore *mutex) +static int target_revfn(const char *name, u8 revision, int *bestp) { - return find_inlist_lock(&ip6t_match, name, "ip6t_", error, mutex); + struct ip6t_target *t; + int have_rev = 0; + + list_for_each_entry(t, &ip6t_target, list) { + if (strcmp(t->name, name) == 0) { + if (t->revision > *bestp) + *bestp = t->revision; + if (t->revision == revision) + have_rev = 1; + } + } + return have_rev; } -static struct ip6t_target * -ip6t_find_target_lock(const char *name, int *error, struct semaphore *mutex) +/* Returns true or fals (if no such extension at all) */ +static inline int find_revision(const char *name, u8 revision, + int (*revfn)(const char *, u8, int *), + int *err) { - return find_inlist_lock(&ip6t_target, name, "ip6t_", error, mutex); + int have_rev, best = -1; + + if (down_interruptible(&ip6t_mutex) != 0) { + *err = -EINTR; + return 1; + } + have_rev = revfn(name, revision, &best); + up(&ip6t_mutex); + + /* Nothing at all? Return 0 to try loading module. */ + if (best == -1) { + *err = -ENOENT; + return 0; + } + + *err = best; + if (!have_rev) + *err = -EPROTONOSUPPORT; + return 1; } + /* All zeroes == unconditional rule. */ static inline int unconditional(const struct ip6t_ip6 *ipv6) @@ -725,20 +792,16 @@ check_match(struct ip6t_entry_match *m, unsigned int hookmask, unsigned int *i) { - int ret; struct ip6t_match *match; - match = find_match_lock(m->u.user.name, &ret, &ip6t_mutex); - if (!match) { - // duprintf("check_match: `%s' not found\n", m->u.name); - return ret; - } - if (!try_module_get(match->me)) { - up(&ip6t_mutex); - return -ENOENT; + match = try_then_request_module(find_match(m->u.user.name, + m->u.user.revision), + "ip6t_%s", m->u.user.name); + if (IS_ERR(match) || !match) { + duprintf("check_match: `%s' not found\n", m->u.user.name); + return match ? PTR_ERR(match) : -ENOENT; } m->u.kernel.match = match; - up(&ip6t_mutex); if (m->u.kernel.match->checkentry && !m->u.kernel.match->checkentry(name, ipv6, m->data, @@ -776,22 +839,16 @@ check_entry(struct ip6t_entry *e, const char *name, unsigned int size, goto cleanup_matches; t = ip6t_get_target(e); - target = ip6t_find_target_lock(t->u.user.name, &ret, &ip6t_mutex); - if (!target) { + target = try_then_request_module(find_target(t->u.user.name, + t->u.user.revision), + "ip6t_%s", t->u.user.name); + if (IS_ERR(target) || !target) { duprintf("check_entry: `%s' not found\n", t->u.user.name); - goto cleanup_matches; - } - if (!try_module_get(target->me)) { - up(&ip6t_mutex); - ret = -ENOENT; + ret = target ? PTR_ERR(target) : -ENOENT; goto cleanup_matches; } t->u.kernel.target = target; - up(&ip6t_mutex); - if (!t->u.kernel.target) { - ret = -EBUSY; - goto cleanup_matches; - } + if (t->u.kernel.target == &ip6t_standard_target) { if (!standard_check(t, size)) { ret = -EINVAL; @@ -1118,8 +1175,8 @@ get_entries(const struct ip6t_get_entries *entries, int ret; struct ip6t_table *t; - t = ip6t_find_table_lock(entries->name, &ret, &ip6t_mutex); - if (t) { + t = find_table_lock(entries->name); + if (t && !IS_ERR(t)) { duprintf("t->private->number = %u\n", t->private->number); if (entries->size == t->private->size) @@ -1131,10 +1188,10 @@ get_entries(const struct ip6t_get_entries *entries, entries->size); ret = -EINVAL; } + module_put(t->me); up(&ip6t_mutex); } else - duprintf("get_entries: Can't find %s!\n", - entries->name); + ret = t ? PTR_ERR(t) : -ENOENT; return ret; } @@ -1182,22 +1239,19 @@ do_replace(void __user *user, unsigned int len) duprintf("ip_tables: Translated table\n"); - t = ip6t_find_table_lock(tmp.name, &ret, &ip6t_mutex); - if (!t) + t = try_then_request_module(find_table_lock(tmp.name), + "ip6table_%s", tmp.name); + if (!t || IS_ERR(t)) { + ret = t ? PTR_ERR(t) : -ENOENT; goto free_newinfo_counters_untrans; + } /* You lied! */ if (tmp.valid_hooks != t->valid_hooks) { duprintf("Valid hook crap: %08X vs %08X\n", tmp.valid_hooks, t->valid_hooks); ret = -EINVAL; - goto free_newinfo_counters_untrans_unlock; - } - - /* Get a reference in advance, we're not allowed fail later */ - if (!try_module_get(t->me)) { - ret = -EBUSY; - goto free_newinfo_counters_untrans_unlock; + goto put_module; } oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret); @@ -1219,7 +1273,6 @@ do_replace(void __user *user, unsigned int len) /* Decrease module usage counts and free resource */ IP6T_ENTRY_ITERATE(oldinfo->entries, oldinfo->size, cleanup_entry,NULL); vfree(oldinfo); - /* Silent error: too late now. */ if (copy_to_user(tmp.counters, counters, sizeof(struct ip6t_counters) * tmp.num_counters) != 0) ret = -EFAULT; @@ -1229,7 +1282,6 @@ do_replace(void __user *user, unsigned int len) put_module: module_put(t->me); - free_newinfo_counters_untrans_unlock: up(&ip6t_mutex); free_newinfo_counters_untrans: IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size, cleanup_entry,NULL); @@ -1268,7 +1320,7 @@ do_add_counters(void __user *user, unsigned int len) unsigned int i; struct ip6t_counters_info tmp, *paddc; struct ip6t_table *t; - int ret; + int ret = 0; if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) return -EFAULT; @@ -1285,9 +1337,11 @@ do_add_counters(void __user *user, unsigned int len) goto free; } - t = ip6t_find_table_lock(tmp.name, &ret, &ip6t_mutex); - if (!t) + t = find_table_lock(tmp.name); + if (!t || IS_ERR(t)) { + ret = t ? PTR_ERR(t) : -ENOENT; goto free; + } write_lock_bh(&t->lock); if (t->private->number != paddc->num_counters) { @@ -1304,6 +1358,7 @@ do_add_counters(void __user *user, unsigned int len) unlock_up_free: write_unlock_bh(&t->lock); up(&ip6t_mutex); + module_put(t->me); free: vfree(paddc); @@ -1360,8 +1415,10 @@ do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) break; } name[IP6T_TABLE_MAXNAMELEN-1] = '\0'; - t = ip6t_find_table_lock(name, &ret, &ip6t_mutex); - if (t) { + + t = try_then_request_module(find_table_lock(name), + "ip6table_%s", name); + if (t && !IS_ERR(t)) { struct ip6t_getinfo info; info.valid_hooks = t->valid_hooks; @@ -1377,9 +1434,10 @@ do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) ret = -EFAULT; else ret = 0; - up(&ip6t_mutex); - } + module_put(t->me); + } else + ret = t ? PTR_ERR(t) : -ENOENT; } break; @@ -1400,6 +1458,31 @@ do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) break; } + case IP6T_SO_GET_REVISION_MATCH: + case IP6T_SO_GET_REVISION_TARGET: { + struct ip6t_get_revision rev; + int (*revfn)(const char *, u8, int *); + + if (*len != sizeof(rev)) { + ret = -EINVAL; + break; + } + if (copy_from_user(&rev, user, sizeof(rev)) != 0) { + ret = -EFAULT; + break; + } + + if (cmd == IP6T_SO_GET_REVISION_TARGET) + revfn = target_revfn; + else + revfn = match_revfn; + + try_then_request_module(find_revision(rev.name, rev.revision, + revfn, &ret), + "ip6t_%s", rev.name); + break; + } + default: duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd); ret = -EINVAL; @@ -1417,12 +1500,7 @@ ip6t_register_target(struct ip6t_target *target) ret = down_interruptible(&ip6t_mutex); if (ret != 0) return ret; - - if (!list_named_insert(&ip6t_target, target)) { - duprintf("ip6t_register_target: `%s' already in list!\n", - target->name); - ret = -EINVAL; - } + list_add(&target->list, &ip6t_target); up(&ip6t_mutex); return ret; } @@ -1444,11 +1522,7 @@ ip6t_register_match(struct ip6t_match *match) if (ret != 0) return ret; - if (!list_named_insert(&ip6t_match, match)) { - duprintf("ip6t_register_match: `%s' already in list!\n", - match->name); - ret = -EINVAL; - } + list_add(&match->list, &ip6t_match); up(&ip6t_mutex); return ret; diff --git a/net/ipv6/netfilter/ip6t_MARK.c b/net/ipv6/netfilter/ip6t_MARK.c index 81924fc..0c7584f 100644 --- a/net/ipv6/netfilter/ip6t_MARK.c +++ b/net/ipv6/netfilter/ip6t_MARK.c @@ -56,8 +56,12 @@ checkentry(const char *tablename, return 1; } -static struct ip6t_target ip6t_mark_reg -= { { NULL, NULL }, "MARK", target, checkentry, NULL, THIS_MODULE }; +static struct ip6t_target ip6t_mark_reg = { + .name = "MARK", + .target = target, + .checkentry = checkentry, + .me = THIS_MODULE +}; static int __init init(void) { |