From a96be24679198469df28976c809575423e70d843 Mon Sep 17 00:00:00 2001 From: Dmitry Mishin Date: Tue, 12 Dec 2006 00:29:26 -0800 Subject: [PATCH] [NETFILTER]: ip_tables: ipt and ipt_compat checks unification Matches and targets verification is duplicated in normal and compat processing ways. This patch refactors code in order to remove this. Signed-off-by: Dmitry Mishin Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/ipv4/netfilter/ip_tables.c | 176 +++++++++++++++------------------ 1 file changed, 79 insertions(+), 97 deletions(-) diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 0ff2956d35..83ebbeb80b 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -484,7 +484,47 @@ cleanup_match(struct ipt_entry_match *m, unsigned int *i) } static inline int -check_match(struct ipt_entry_match *m, +check_entry(struct ipt_entry *e, const char *name) +{ + struct ipt_entry_target *t; + + if (!ip_checkentry(&e->ip)) { + duprintf("ip_tables: ip check failed %p %s.\n", e, name); + return -EINVAL; + } + + if (e->target_offset + sizeof(struct ipt_entry_target) > e->next_offset) + return -EINVAL; + + t = ipt_get_target(e); + if (e->target_offset + t->u.target_size > e->next_offset) + return -EINVAL; + + return 0; +} + +static inline int check_match(struct ipt_entry_match *m, const char *name, + const struct ipt_ip *ip, unsigned int hookmask) +{ + struct ipt_match *match; + int ret; + + match = m->u.kernel.match; + ret = xt_check_match(match, AF_INET, m->u.match_size - sizeof(*m), + name, hookmask, ip->proto, + ip->invflags & IPT_INV_PROTO); + if (!ret && m->u.kernel.match->checkentry + && !m->u.kernel.match->checkentry(name, ip, match, m->data, + hookmask)) { + duprintf("ip_tables: check failed for `%s'.\n", + m->u.kernel.match->name); + ret = -EINVAL; + } + return ret; +} + +static inline int +find_check_match(struct ipt_entry_match *m, const char *name, const struct ipt_ip *ip, unsigned int hookmask, @@ -497,26 +537,15 @@ check_match(struct ipt_entry_match *m, m->u.user.revision), "ipt_%s", m->u.user.name); if (IS_ERR(match) || !match) { - duprintf("check_match: `%s' not found\n", m->u.user.name); + duprintf("find_check_match: `%s' not found\n", m->u.user.name); return match ? PTR_ERR(match) : -ENOENT; } m->u.kernel.match = match; - ret = xt_check_match(match, AF_INET, m->u.match_size - sizeof(*m), - name, hookmask, ip->proto, - ip->invflags & IPT_INV_PROTO); + ret = check_match(m, name, ip, hookmask); if (ret) goto err; - if (m->u.kernel.match->checkentry - && !m->u.kernel.match->checkentry(name, ip, match, m->data, - hookmask)) { - duprintf("ip_tables: check failed for `%s'.\n", - m->u.kernel.match->name); - ret = -EINVAL; - goto err; - } - (*i)++; return 0; err: @@ -524,10 +553,29 @@ err: return ret; } -static struct ipt_target ipt_standard_target; +static inline int check_target(struct ipt_entry *e, const char *name) +{ + struct ipt_entry_target *t; + struct ipt_target *target; + int ret; + + t = ipt_get_target(e); + target = t->u.kernel.target; + ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), + name, e->comefrom, e->ip.proto, + e->ip.invflags & IPT_INV_PROTO); + if (!ret && t->u.kernel.target->checkentry + && !t->u.kernel.target->checkentry(name, e, target, + t->data, e->comefrom)) { + duprintf("ip_tables: check failed for `%s'.\n", + t->u.kernel.target->name); + ret = -EINVAL; + } + return ret; +} static inline int -check_entry(struct ipt_entry *e, const char *name, unsigned int size, +find_check_entry(struct ipt_entry *e, const char *name, unsigned int size, unsigned int *i) { struct ipt_entry_target *t; @@ -535,49 +583,32 @@ check_entry(struct ipt_entry *e, const char *name, unsigned int size, int ret; unsigned int j; - if (!ip_checkentry(&e->ip)) { - duprintf("ip_tables: ip check failed %p %s.\n", e, name); - return -EINVAL; - } - - if (e->target_offset + sizeof(struct ipt_entry_target) > e->next_offset) - return -EINVAL; + ret = check_entry(e, name); + if (ret) + return ret; j = 0; - ret = IPT_MATCH_ITERATE(e, check_match, name, &e->ip, e->comefrom, &j); + ret = IPT_MATCH_ITERATE(e, find_check_match, name, &e->ip, + e->comefrom, &j); if (ret != 0) goto cleanup_matches; t = ipt_get_target(e); - ret = -EINVAL; - if (e->target_offset + t->u.target_size > e->next_offset) - goto cleanup_matches; target = try_then_request_module(xt_find_target(AF_INET, t->u.user.name, t->u.user.revision), "ipt_%s", t->u.user.name); if (IS_ERR(target) || !target) { - duprintf("check_entry: `%s' not found\n", t->u.user.name); + duprintf("find_check_entry: `%s' not found\n", t->u.user.name); ret = target ? PTR_ERR(target) : -ENOENT; goto cleanup_matches; } t->u.kernel.target = target; - ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), - name, e->comefrom, e->ip.proto, - e->ip.invflags & IPT_INV_PROTO); + ret = check_target(e, name); if (ret) goto err; - if (t->u.kernel.target->checkentry - && !t->u.kernel.target->checkentry(name, e, target, t->data, - e->comefrom)) { - duprintf("ip_tables: check failed for `%s'.\n", - t->u.kernel.target->name); - ret = -EINVAL; - goto err; - } - (*i)++; return 0; err: @@ -712,7 +743,7 @@ translate_table(const char *name, /* Finally, each sanity check must pass */ i = 0; ret = IPT_ENTRY_ITERATE(entry0, newinfo->size, - check_entry, name, size, &i); + find_check_entry, name, size, &i); if (ret != 0) { IPT_ENTRY_ITERATE(entry0, newinfo->size, @@ -1452,14 +1483,9 @@ check_compat_entry_size_and_hooks(struct ipt_entry *e, return -EINVAL; } - if (!ip_checkentry(&e->ip)) { - duprintf("ip_tables: ip check failed %p %s.\n", e, name); - return -EINVAL; - } - - if (e->target_offset + sizeof(struct compat_xt_entry_target) > - e->next_offset) - return -EINVAL; + ret = check_entry(e, name); + if (ret) + return ret; off = 0; entry_offset = (void *)e - (void *)base; @@ -1470,15 +1496,13 @@ check_compat_entry_size_and_hooks(struct ipt_entry *e, goto cleanup_matches; t = ipt_get_target(e); - ret = -EINVAL; - if (e->target_offset + t->u.target_size > e->next_offset) - goto cleanup_matches; target = try_then_request_module(xt_find_target(AF_INET, t->u.user.name, t->u.user.revision), "ipt_%s", t->u.user.name); if (IS_ERR(target) || !target) { - duprintf("check_entry: `%s' not found\n", t->u.user.name); + duprintf("check_compat_entry_size_and_hooks: `%s' not found\n", + t->u.user.name); ret = target ? PTR_ERR(target) : -ENOENT; goto cleanup_matches; } @@ -1555,57 +1579,15 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr, return ret; } -static inline int compat_check_match(struct ipt_entry_match *m, const char *name, - const struct ipt_ip *ip, unsigned int hookmask) -{ - struct ipt_match *match; - int ret; - - match = m->u.kernel.match; - ret = xt_check_match(match, AF_INET, m->u.match_size - sizeof(*m), - name, hookmask, ip->proto, - ip->invflags & IPT_INV_PROTO); - if (!ret && m->u.kernel.match->checkentry - && !m->u.kernel.match->checkentry(name, ip, match, m->data, - hookmask)) { - duprintf("ip_tables: compat: check failed for `%s'.\n", - m->u.kernel.match->name); - ret = -EINVAL; - } - return ret; -} - -static inline int compat_check_target(struct ipt_entry *e, const char *name) -{ - struct ipt_entry_target *t; - struct ipt_target *target; - int ret; - - t = ipt_get_target(e); - target = t->u.kernel.target; - ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), - name, e->comefrom, e->ip.proto, - e->ip.invflags & IPT_INV_PROTO); - if (!ret && t->u.kernel.target->checkentry - && !t->u.kernel.target->checkentry(name, e, target, - t->data, e->comefrom)) { - duprintf("ip_tables: compat: check failed for `%s'.\n", - t->u.kernel.target->name); - ret = -EINVAL; - } - return ret; -} - static inline int compat_check_entry(struct ipt_entry *e, const char *name) { int ret; - ret = IPT_MATCH_ITERATE(e, compat_check_match, name, &e->ip, - e->comefrom); + ret = IPT_MATCH_ITERATE(e, check_match, name, &e->ip, e->comefrom); if (ret) return ret; - return compat_check_target(e, name); + return check_target(e, name); } static int -- 2.39.5