3 /* Library which manipulates filtering rules. */
5 #include <linux/types.h>
6 #include <libiptc/ipt_kernel_headers.h>
7 #include <linux/netfilter_ipv4/ip_tables.h>
14 /* ipt_entry has pointers and u_int64_t's in it, so if you align to
15 it, you'll also align to any crazy matches and targets someone
17 #define IPT_MIN_ALIGN (__alignof__(struct ipt_entry))
20 #define IPT_ALIGN(s) (((s) + ((IPT_MIN_ALIGN)-1)) & ~((IPT_MIN_ALIGN)-1))
22 typedef char ipt_chainlabel[32];
24 #define IPTC_LABEL_ACCEPT "ACCEPT"
25 #define IPTC_LABEL_DROP "DROP"
26 #define IPTC_LABEL_QUEUE "QUEUE"
27 #define IPTC_LABEL_RETURN "RETURN"
29 /* Transparent handle type. */
30 typedef struct iptc_handle *iptc_handle_t;
32 /* Does this chain exist? */
33 int iptc_is_chain(const char *chain, const iptc_handle_t handle);
35 /* Take a snapshot of the rules. Returns NULL on error. */
36 iptc_handle_t iptc_init(const char *tablename);
38 /* Cleanup after iptc_init(). */
39 void iptc_free(iptc_handle_t *h);
41 /* Iterator functions to run through the chains. Returns NULL at end. */
42 const char *iptc_first_chain(iptc_handle_t *handle);
43 const char *iptc_next_chain(iptc_handle_t *handle);
45 /* Get first rule in the given chain: NULL for empty chain. */
46 const struct ipt_entry *iptc_first_rule(const char *chain,
47 iptc_handle_t *handle);
49 /* Returns NULL when rules run out. */
50 const struct ipt_entry *iptc_next_rule(const struct ipt_entry *prev,
51 iptc_handle_t *handle);
53 /* Returns a pointer to the target name of this entry. */
54 const char *iptc_get_target(const struct ipt_entry *e,
55 iptc_handle_t *handle);
57 /* Is this a built-in chain? */
58 int iptc_builtin(const char *chain, const iptc_handle_t handle);
60 /* Get the policy of a given built-in chain */
61 const char *iptc_get_policy(const char *chain,
62 struct ipt_counters *counter,
63 iptc_handle_t *handle);
65 /* These functions return TRUE for OK or 0 and set errno. If errno ==
66 0, it means there was a version error (ie. upgrade libiptc). */
67 /* Rule numbers start at 1 for the first rule. */
69 /* Insert the entry `e' in chain `chain' into position `rulenum'. */
70 int iptc_insert_entry(const ipt_chainlabel chain,
71 const struct ipt_entry *e,
73 iptc_handle_t *handle);
75 /* Atomically replace rule `rulenum' in `chain' with `e'. */
76 int iptc_replace_entry(const ipt_chainlabel chain,
77 const struct ipt_entry *e,
79 iptc_handle_t *handle);
81 /* Append entry `e' to chain `chain'. Equivalent to insert with
82 rulenum = length of chain. */
83 int iptc_append_entry(const ipt_chainlabel chain,
84 const struct ipt_entry *e,
85 iptc_handle_t *handle);
87 /* Delete the first rule in `chain' which matches `e', subject to
88 matchmask (array of length == origfw) */
89 int iptc_delete_entry(const ipt_chainlabel chain,
90 const struct ipt_entry *origfw,
91 unsigned char *matchmask,
92 iptc_handle_t *handle);
94 /* Delete the rule in position `rulenum' in `chain'. */
95 int iptc_delete_num_entry(const ipt_chainlabel chain,
97 iptc_handle_t *handle);
99 /* Check the packet `e' on chain `chain'. Returns the verdict, or
100 NULL and sets errno. */
101 const char *iptc_check_packet(const ipt_chainlabel chain,
102 struct ipt_entry *entry,
103 iptc_handle_t *handle);
105 /* Flushes the entries in the given chain (ie. empties chain). */
106 int iptc_flush_entries(const ipt_chainlabel chain,
107 iptc_handle_t *handle);
109 /* Zeroes the counters in a chain. */
110 int iptc_zero_entries(const ipt_chainlabel chain,
111 iptc_handle_t *handle);
113 /* Creates a new chain. */
114 int iptc_create_chain(const ipt_chainlabel chain,
115 iptc_handle_t *handle);
117 /* Deletes a chain. */
118 int iptc_delete_chain(const ipt_chainlabel chain,
119 iptc_handle_t *handle);
121 /* Renames a chain. */
122 int iptc_rename_chain(const ipt_chainlabel oldname,
123 const ipt_chainlabel newname,
124 iptc_handle_t *handle);
126 /* Sets the policy on a built-in chain. */
127 int iptc_set_policy(const ipt_chainlabel chain,
128 const ipt_chainlabel policy,
129 struct ipt_counters *counters,
130 iptc_handle_t *handle);
132 /* Get the number of references to this chain */
133 int iptc_get_references(unsigned int *ref,
134 const ipt_chainlabel chain,
135 iptc_handle_t *handle);
137 /* read packet and byte counters for a specific rule */
138 struct ipt_counters *iptc_read_counter(const ipt_chainlabel chain,
139 unsigned int rulenum,
140 iptc_handle_t *handle);
142 /* zero packet and byte counters for a specific rule */
143 int iptc_zero_counter(const ipt_chainlabel chain,
144 unsigned int rulenum,
145 iptc_handle_t *handle);
147 /* set packet and byte counters for a specific rule */
148 int iptc_set_counter(const ipt_chainlabel chain,
149 unsigned int rulenum,
150 struct ipt_counters *counters,
151 iptc_handle_t *handle);
153 /* Makes the actual changes. */
154 int iptc_commit(iptc_handle_t *handle);
156 /* Get raw socket. */
157 int iptc_get_raw_socket(void);
159 /* Translates errno numbers into more human-readable form than strerror. */
160 const char *iptc_strerror(int err);
162 extern void dump_entries(const iptc_handle_t);
169 #endif /* _LIBIPTC_H */