1 #ifndef _LIBIPTC_H 2 #define _LIBIPTC_H 3 /* Library which manipulates filtering rules. */ 4 5 #include <linux/types.h> 6 #include <libiptc/ipt_kernel_headers.h> 7 #ifdef __cplusplus 8 # include <climits> 9 #else 10 # include <limits.h> /* INT_MAX in ip_tables.h */ 11 #endif 12 #include <linux/netfilter_ipv4/ip_tables.h> 13 14 #ifdef __cplusplus 15 extern "C" { 16 #endif 17 18 struct iptc_handle; 19 20 typedef char ipt_chainlabel[32]; 21 22 #define IPTC_LABEL_ACCEPT "ACCEPT" 23 #define IPTC_LABEL_DROP "DROP" 24 #define IPTC_LABEL_QUEUE "QUEUE" 25 #define IPTC_LABEL_RETURN "RETURN" 26 27 /* Does this chain exist? */ 28 int iptc_is_chain(const char *chain, struct iptc_handle *const handle); 29 30 /* Take a snapshot of the rules. Returns NULL on error. */ 31 struct iptc_handle *iptc_init(const char *tablename); 32 33 /* Cleanup after iptc_init(). */ 34 void iptc_free(struct iptc_handle *h); 35 36 /* Iterator functions to run through the chains. Returns NULL at end. */ 37 const char *iptc_first_chain(struct iptc_handle *handle); 38 const char *iptc_next_chain(struct iptc_handle *handle); 39 40 /* Get first rule in the given chain: NULL for empty chain. */ 41 const struct ipt_entry *iptc_first_rule(const char *chain, 42 struct iptc_handle *handle); 43 44 /* Returns NULL when rules run out. */ 45 const struct ipt_entry *iptc_next_rule(const struct ipt_entry *prev, 46 struct iptc_handle *handle); 47 48 /* Returns a pointer to the target name of this entry. */ 49 const char *iptc_get_target(const struct ipt_entry *e, 50 struct iptc_handle *handle); 51 52 /* Is this a built-in chain? */ 53 int iptc_builtin(const char *chain, struct iptc_handle *const handle); 54 55 /* Get the policy of a given built-in chain */ 56 const char *iptc_get_policy(const char *chain, 57 struct ipt_counters *counter, 58 struct iptc_handle *handle); 59 60 /* These functions return TRUE for OK or 0 and set errno. If errno == 61 0, it means there was a version error (ie. upgrade libiptc). */ 62 /* Rule numbers start at 1 for the first rule. */ 63 64 /* Insert the entry `e' in chain `chain' into position `rulenum'. */ 65 int iptc_insert_entry(const ipt_chainlabel chain, 66 const struct ipt_entry *e, 67 unsigned int rulenum, 68 struct iptc_handle *handle); 69 70 /* Atomically replace rule `rulenum' in `chain' with `e'. */ 71 int iptc_replace_entry(const ipt_chainlabel chain, 72 const struct ipt_entry *e, 73 unsigned int rulenum, 74 struct iptc_handle *handle); 75 76 /* Append entry `e' to chain `chain'. Equivalent to insert with 77 rulenum = length of chain. */ 78 int iptc_append_entry(const ipt_chainlabel chain, 79 const struct ipt_entry *e, 80 struct iptc_handle *handle); 81 82 /* Check whether a mathching rule exists */ 83 int iptc_check_entry(const ipt_chainlabel chain, 84 const struct ipt_entry *origfw, 85 unsigned char *matchmask, 86 struct iptc_handle *handle); 87 88 /* Delete the first rule in `chain' which matches `e', subject to 89 matchmask (array of length == origfw) */ 90 int iptc_delete_entry(const ipt_chainlabel chain, 91 const struct ipt_entry *origfw, 92 unsigned char *matchmask, 93 struct iptc_handle *handle); 94 95 /* Delete the rule in position `rulenum' in `chain'. */ 96 int iptc_delete_num_entry(const ipt_chainlabel chain, 97 unsigned int rulenum, 98 struct iptc_handle *handle); 99 100 /* Check the packet `e' on chain `chain'. Returns the verdict, or 101 NULL and sets errno. */ 102 const char *iptc_check_packet(const ipt_chainlabel chain, 103 struct ipt_entry *entry, 104 struct iptc_handle *handle); 105 106 /* Flushes the entries in the given chain (ie. empties chain). */ 107 int iptc_flush_entries(const ipt_chainlabel chain, 108 struct iptc_handle *handle); 109 110 /* Zeroes the counters in a chain. */ 111 int iptc_zero_entries(const ipt_chainlabel chain, 112 struct iptc_handle *handle); 113 114 /* Creates a new chain. */ 115 int iptc_create_chain(const ipt_chainlabel chain, 116 struct iptc_handle *handle); 117 118 /* Deletes a chain. */ 119 int iptc_delete_chain(const ipt_chainlabel chain, 120 struct iptc_handle *handle); 121 122 /* Renames a chain. */ 123 int iptc_rename_chain(const ipt_chainlabel oldname, 124 const ipt_chainlabel newname, 125 struct iptc_handle *handle); 126 127 /* Sets the policy on a built-in chain. */ 128 int iptc_set_policy(const ipt_chainlabel chain, 129 const ipt_chainlabel policy, 130 struct ipt_counters *counters, 131 struct iptc_handle *handle); 132 133 /* Get the number of references to this chain */ 134 int iptc_get_references(unsigned int *ref, 135 const ipt_chainlabel chain, 136 struct iptc_handle *handle); 137 138 /* read packet and byte counters for a specific rule */ 139 struct ipt_counters *iptc_read_counter(const ipt_chainlabel chain, 140 unsigned int rulenum, 141 struct iptc_handle *handle); 142 143 /* zero packet and byte counters for a specific rule */ 144 int iptc_zero_counter(const ipt_chainlabel chain, 145 unsigned int rulenum, 146 struct iptc_handle *handle); 147 148 /* set packet and byte counters for a specific rule */ 149 int iptc_set_counter(const ipt_chainlabel chain, 150 unsigned int rulenum, 151 struct ipt_counters *counters, 152 struct iptc_handle *handle); 153 154 /* Makes the actual changes. */ 155 int iptc_commit(struct iptc_handle *handle); 156 157 /* Get raw socket. */ 158 int iptc_get_raw_socket(void); 159 160 /* Translates errno numbers into more human-readable form than strerror. */ 161 const char *iptc_strerror(int err); 162 163 extern void dump_entries(struct iptc_handle *const); 164 165 #ifdef __cplusplus 166 } 167 #endif 168 169 170 #endif /* _LIBIPTC_H */ 171
