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path: root/net/ipv4/netfilter/ip_tables.c
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Diffstat (limited to 'net/ipv4/netfilter/ip_tables.c')
-rw-r--r--net/ipv4/netfilter/ip_tables.c258
1 files changed, 202 insertions, 56 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index e3f83bf160d..e1b402c6b85 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -152,20 +152,20 @@ ip_packet_match(const struct iphdr *ip,
return 1;
}
-static inline int
+static inline bool
ip_checkentry(const struct ipt_ip *ip)
{
if (ip->flags & ~IPT_F_MASK) {
duprintf("Unknown flag bits set: %08X\n",
ip->flags & ~IPT_F_MASK);
- return 0;
+ return false;
}
if (ip->invflags & ~IPT_INV_MASK) {
duprintf("Unknown invflag bits set: %08X\n",
ip->invflags & ~IPT_INV_MASK);
- return 0;
+ return false;
}
- return 1;
+ return true;
}
static unsigned int
@@ -183,19 +183,19 @@ ipt_error(struct sk_buff **pskb,
}
static inline
-int do_match(struct ipt_entry_match *m,
- const struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int offset,
- int *hotdrop)
+bool do_match(struct ipt_entry_match *m,
+ const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int offset,
+ bool *hotdrop)
{
/* Stop iteration if it doesn't match */
if (!m->u.kernel.match->match(skb, in, out, m->u.kernel.match, m->data,
offset, ip_hdrlen(skb), hotdrop))
- return 1;
+ return true;
else
- return 0;
+ return false;
}
static inline struct ipt_entry *
@@ -204,6 +204,112 @@ get_entry(void *base, unsigned int offset)
return (struct ipt_entry *)(base + offset);
}
+/* All zeroes == unconditional rule. */
+static inline int
+unconditional(const struct ipt_ip *ip)
+{
+ unsigned int i;
+
+ for (i = 0; i < sizeof(*ip)/sizeof(__u32); i++)
+ if (((__u32 *)ip)[i])
+ return 0;
+
+ return 1;
+}
+
+#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
+ defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
+static const char *hooknames[] = {
+ [NF_IP_PRE_ROUTING] = "PREROUTING",
+ [NF_IP_LOCAL_IN] = "INPUT",
+ [NF_IP_FORWARD] = "FORWARD",
+ [NF_IP_LOCAL_OUT] = "OUTPUT",
+ [NF_IP_POST_ROUTING] = "POSTROUTING",
+};
+
+enum nf_ip_trace_comments {
+ NF_IP_TRACE_COMMENT_RULE,
+ NF_IP_TRACE_COMMENT_RETURN,
+ NF_IP_TRACE_COMMENT_POLICY,
+};
+
+static const char *comments[] = {
+ [NF_IP_TRACE_COMMENT_RULE] = "rule",
+ [NF_IP_TRACE_COMMENT_RETURN] = "return",
+ [NF_IP_TRACE_COMMENT_POLICY] = "policy",
+};
+
+static struct nf_loginfo trace_loginfo = {
+ .type = NF_LOG_TYPE_LOG,
+ .u = {
+ .log = {
+ .level = 4,
+ .logflags = NF_LOG_MASK,
+ },
+ },
+};
+
+static inline int
+get_chainname_rulenum(struct ipt_entry *s, struct ipt_entry *e,
+ char *hookname, char **chainname,
+ char **comment, unsigned int *rulenum)
+{
+ struct ipt_standard_target *t = (void *)ipt_get_target(s);
+
+ if (strcmp(t->target.u.kernel.target->name, IPT_ERROR_TARGET) == 0) {
+ /* Head of user chain: ERROR target with chainname */
+ *chainname = t->target.data;
+ (*rulenum) = 0;
+ } else if (s == e) {
+ (*rulenum)++;
+
+ if (s->target_offset == sizeof(struct ipt_entry)
+ && strcmp(t->target.u.kernel.target->name,
+ IPT_STANDARD_TARGET) == 0
+ && t->verdict < 0
+ && unconditional(&s->ip)) {
+ /* Tail of chains: STANDARD target (return/policy) */
+ *comment = *chainname == hookname
+ ? (char *)comments[NF_IP_TRACE_COMMENT_POLICY]
+ : (char *)comments[NF_IP_TRACE_COMMENT_RETURN];
+ }
+ return 1;
+ } else
+ (*rulenum)++;
+
+ return 0;
+}
+
+static void trace_packet(struct sk_buff *skb,
+ unsigned int hook,
+ const struct net_device *in,
+ const struct net_device *out,
+ char *tablename,
+ struct xt_table_info *private,
+ struct ipt_entry *e)
+{
+ void *table_base;
+ struct ipt_entry *root;
+ char *hookname, *chainname, *comment;
+ unsigned int rulenum = 0;
+
+ table_base = (void *)private->entries[smp_processor_id()];
+ root = get_entry(table_base, private->hook_entry[hook]);
+
+ hookname = chainname = (char *)hooknames[hook];
+ comment = (char *)comments[NF_IP_TRACE_COMMENT_RULE];
+
+ IPT_ENTRY_ITERATE(root,
+ private->size - private->hook_entry[hook],
+ get_chainname_rulenum,
+ e, hookname, &chainname, &comment, &rulenum);
+
+ nf_log_packet(AF_INET, hook, skb, in, out, &trace_loginfo,
+ "TRACE: %s:%s:%s:%u ",
+ tablename, chainname, comment, rulenum);
+}
+#endif
+
/* Returns one of the generic firewall policies, like NF_ACCEPT. */
unsigned int
ipt_do_table(struct sk_buff **pskb,
@@ -216,7 +322,7 @@ ipt_do_table(struct sk_buff **pskb,
u_int16_t offset;
struct iphdr *ip;
u_int16_t datalen;
- int hotdrop = 0;
+ bool hotdrop = false;
/* Initializing verdict to NF_DROP keeps gcc happy. */
unsigned int verdict = NF_DROP;
const char *indev, *outdev;
@@ -261,6 +367,14 @@ ipt_do_table(struct sk_buff **pskb,
t = ipt_get_target(e);
IP_NF_ASSERT(t->u.kernel.target);
+
+#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
+ defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
+ /* The packet is traced: log it */
+ if (unlikely((*pskb)->nf_trace))
+ trace_packet(*pskb, hook, in, out,
+ table->name, private, e);
+#endif
/* Standard target? */
if (!t->u.kernel.target->target) {
int v;
@@ -341,19 +455,6 @@ ipt_do_table(struct sk_buff **pskb,
#endif
}
-/* All zeroes == unconditional rule. */
-static inline int
-unconditional(const struct ipt_ip *ip)
-{
- unsigned int i;
-
- for (i = 0; i < sizeof(*ip)/sizeof(__u32); i++)
- if (((__u32 *)ip)[i])
- return 0;
-
- return 1;
-}
-
/* Figures out from what hook each rule can be called: returns 0 if
there are loops. Puts hook bitmask in comefrom. */
static int
@@ -499,7 +600,8 @@ check_entry(struct ipt_entry *e, const char *name)
}
static inline int check_match(struct ipt_entry_match *m, const char *name,
- const struct ipt_ip *ip, unsigned int hookmask)
+ const struct ipt_ip *ip, unsigned int hookmask,
+ unsigned int *i)
{
struct xt_match *match;
int ret;
@@ -515,6 +617,8 @@ static inline int check_match(struct ipt_entry_match *m, const char *name,
m->u.kernel.match->name);
ret = -EINVAL;
}
+ if (!ret)
+ (*i)++;
return ret;
}
@@ -537,11 +641,10 @@ find_check_match(struct ipt_entry_match *m,
}
m->u.kernel.match = match;
- ret = check_match(m, name, ip, hookmask);
+ ret = check_match(m, name, ip, hookmask, i);
if (ret)
goto err;
- (*i)++;
return 0;
err:
module_put(m->u.kernel.match->me);
@@ -1425,7 +1528,7 @@ out:
}
static inline int
-compat_check_calc_match(struct ipt_entry_match *m,
+compat_find_calc_match(struct ipt_entry_match *m,
const char *name,
const struct ipt_ip *ip,
unsigned int hookmask,
@@ -1449,6 +1552,31 @@ compat_check_calc_match(struct ipt_entry_match *m,
}
static inline int
+compat_release_match(struct ipt_entry_match *m, unsigned int *i)
+{
+ if (i && (*i)-- == 0)
+ return 1;
+
+ module_put(m->u.kernel.match->me);
+ return 0;
+}
+
+static inline int
+compat_release_entry(struct ipt_entry *e, unsigned int *i)
+{
+ struct ipt_entry_target *t;
+
+ if (i && (*i)-- == 0)
+ return 1;
+
+ /* Cleanup all matches */
+ IPT_MATCH_ITERATE(e, compat_release_match, NULL);
+ t = ipt_get_target(e);
+ module_put(t->u.kernel.target->me);
+ return 0;
+}
+
+static inline int
check_compat_entry_size_and_hooks(struct ipt_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
@@ -1485,10 +1613,10 @@ check_compat_entry_size_and_hooks(struct ipt_entry *e,
off = 0;
entry_offset = (void *)e - (void *)base;
j = 0;
- ret = IPT_MATCH_ITERATE(e, compat_check_calc_match, name, &e->ip,
+ ret = IPT_MATCH_ITERATE(e, compat_find_calc_match, name, &e->ip,
e->comefrom, &off, &j);
if (ret != 0)
- goto cleanup_matches;
+ goto release_matches;
t = ipt_get_target(e);
target = try_then_request_module(xt_find_target(AF_INET,
@@ -1499,7 +1627,7 @@ check_compat_entry_size_and_hooks(struct ipt_entry *e,
duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
t->u.user.name);
ret = target ? PTR_ERR(target) : -ENOENT;
- goto cleanup_matches;
+ goto release_matches;
}
t->u.kernel.target = target;
@@ -1526,8 +1654,8 @@ check_compat_entry_size_and_hooks(struct ipt_entry *e,
out:
module_put(t->u.kernel.target->me);
-cleanup_matches:
- IPT_MATCH_ITERATE(e, cleanup_match, &j);
+release_matches:
+ IPT_MATCH_ITERATE(e, compat_release_match, &j);
return ret;
}
@@ -1574,15 +1702,26 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr,
return ret;
}
-static inline int compat_check_entry(struct ipt_entry *e, const char *name)
+static inline int compat_check_entry(struct ipt_entry *e, const char *name,
+ unsigned int *i)
{
- int ret;
+ int j, ret;
- ret = IPT_MATCH_ITERATE(e, check_match, name, &e->ip, e->comefrom);
+ j = 0;
+ ret = IPT_MATCH_ITERATE(e, check_match, name, &e->ip, e->comefrom, &j);
if (ret)
- return ret;
+ goto cleanup_matches;
+
+ ret = check_target(e, name);
+ if (ret)
+ goto cleanup_matches;
+
+ (*i)++;
+ return 0;
- return check_target(e, name);
+ cleanup_matches:
+ IPT_MATCH_ITERATE(e, cleanup_match, &j);
+ return ret;
}
static int
@@ -1673,10 +1812,17 @@ translate_compat_table(const char *name,
if (!mark_source_chains(newinfo, valid_hooks, entry1))
goto free_newinfo;
+ i = 0;
ret = IPT_ENTRY_ITERATE(entry1, newinfo->size, compat_check_entry,
- name);
- if (ret)
- goto free_newinfo;
+ name, &i);
+ if (ret) {
+ j -= i;
+ IPT_ENTRY_ITERATE_CONTINUE(entry1, newinfo->size, i,
+ compat_release_entry, &j);
+ IPT_ENTRY_ITERATE(entry1, newinfo->size, cleanup_entry, &i);
+ xt_free_table_info(newinfo);
+ return ret;
+ }
/* And one copy for every other CPU */
for_each_possible_cpu(i)
@@ -1691,7 +1837,7 @@ translate_compat_table(const char *name,
free_newinfo:
xt_free_table_info(newinfo);
out:
- IPT_ENTRY_ITERATE(entry0, total_size, cleanup_entry, &j);
+ IPT_ENTRY_ITERATE(entry0, total_size, compat_release_entry, &j);
return ret;
out_unlock:
compat_flush_offsets();
@@ -2060,16 +2206,16 @@ void ipt_unregister_table(struct xt_table *table)
}
/* Returns 1 if the type and code is matched by the range, 0 otherwise */
-static inline int
+static inline bool
icmp_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code,
u_int8_t type, u_int8_t code,
- int invert)
+ bool invert)
{
return ((test_type == 0xFF) || (type == test_type && code >= min_code && code <= max_code))
^ invert;
}
-static int
+static bool
icmp_match(const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
@@ -2077,14 +2223,14 @@ icmp_match(const struct sk_buff *skb,
const void *matchinfo,
int offset,
unsigned int protoff,
- int *hotdrop)
+ bool *hotdrop)
{
struct icmphdr _icmph, *ic;
const struct ipt_icmp *icmpinfo = matchinfo;
/* Must not be a fragment. */
if (offset)
- return 0;
+ return false;
ic = skb_header_pointer(skb, protoff, sizeof(_icmph), &_icmph);
if (ic == NULL) {
@@ -2092,8 +2238,8 @@ icmp_match(const struct sk_buff *skb,
* can't. Hence, no choice but to drop.
*/
duprintf("Dropping evil ICMP tinygram.\n");
- *hotdrop = 1;
- return 0;
+ *hotdrop = true;
+ return false;
}
return icmp_type_code_match(icmpinfo->type,
@@ -2104,7 +2250,7 @@ icmp_match(const struct sk_buff *skb,
}
/* Called when user tries to insert an entry of this type. */
-static int
+static bool
icmp_checkentry(const char *tablename,
const void *info,
const struct xt_match *match,
@@ -2118,7 +2264,7 @@ icmp_checkentry(const char *tablename,
}
/* The built-in targets: standard (NULL) and error. */
-static struct xt_target ipt_standard_target = {
+static struct xt_target ipt_standard_target __read_mostly = {
.name = IPT_STANDARD_TARGET,
.targetsize = sizeof(int),
.family = AF_INET,
@@ -2129,7 +2275,7 @@ static struct xt_target ipt_standard_target = {
#endif
};
-static struct xt_target ipt_error_target = {
+static struct xt_target ipt_error_target __read_mostly = {
.name = IPT_ERROR_TARGET,
.target = ipt_error,
.targetsize = IPT_FUNCTION_MAXNAMELEN,
@@ -2152,7 +2298,7 @@ static struct nf_sockopt_ops ipt_sockopts = {
#endif
};
-static struct xt_match icmp_matchstruct = {
+static struct xt_match icmp_matchstruct __read_mostly = {
.name = "icmp",
.match = icmp_match,
.matchsize = sizeof(struct ipt_icmp),
@@ -2185,7 +2331,7 @@ static int __init ip_tables_init(void)
if (ret < 0)
goto err5;
- printk("ip_tables: (C) 2000-2006 Netfilter Core Team\n");
+ printk(KERN_INFO "ip_tables: (C) 2000-2006 Netfilter Core Team\n");
return 0;
err5: