1 #include <stdbool.h> 2 #include <stdlib.h> 3 #include <stdio.h> 4 #include <string.h> 5 #include <getopt.h> 6 #include <xtables.h> 7 8 #include <linux/netfilter/x_tables.h> 9 #include <linux/netfilter/xt_NFLOG.h> 10 11 enum { 12 O_GROUP = 0, 13 O_PREFIX, 14 O_RANGE, 15 O_SIZE, 16 O_THRESHOLD, 17 F_RANGE = 1 << O_RANGE, 18 F_SIZE = 1 << O_SIZE, 19 }; 20 21 #define s struct xt_nflog_info 22 static const struct xt_option_entry NFLOG_opts[] = { 23 {.name = "nflog-group", .id = O_GROUP, .type = XTTYPE_UINT16, 24 .flags = XTOPT_PUT, XTOPT_POINTER(s, group)}, 25 {.name = "nflog-prefix", .id = O_PREFIX, .type = XTTYPE_STRING, 26 .min = 1, .flags = XTOPT_PUT, XTOPT_POINTER(s, prefix)}, 27 {.name = "nflog-range", .id = O_RANGE, .type = XTTYPE_UINT32, 28 .excl = F_SIZE, .flags = XTOPT_PUT, XTOPT_POINTER(s, len)}, 29 {.name = "nflog-size", .id = O_SIZE, .type = XTTYPE_UINT32, 30 .excl = F_RANGE, .flags = XTOPT_PUT, XTOPT_POINTER(s, len)}, 31 {.name = "nflog-threshold", .id = O_THRESHOLD, .type = XTTYPE_UINT16, 32 .flags = XTOPT_PUT, XTOPT_POINTER(s, threshold)}, 33 XTOPT_TABLEEND, 34 }; 35 #undef s 36 37 static void NFLOG_help(void) 38 { 39 printf("NFLOG target options:\n" 40 " --nflog-group NUM NETLINK group used for logging\n" 41 " --nflog-range NUM This option has no effect, use --nflog-size\n" 42 " --nflog-size NUM Number of bytes to copy\n" 43 " --nflog-threshold NUM Message threshold of in-kernel queue\n" 44 " --nflog-prefix STRING Prefix string for log messages\n"); 45 } 46 47 static void NFLOG_init(struct xt_entry_target *t) 48 { 49 struct xt_nflog_info *info = (struct xt_nflog_info *)t->data; 50 51 info->threshold = XT_NFLOG_DEFAULT_THRESHOLD; 52 } 53 54 static void NFLOG_parse(struct xt_option_call *cb) 55 { 56 xtables_option_parse(cb); 57 switch (cb->entry->id) { 58 case O_PREFIX: 59 if (strchr(cb->arg, '\n') != NULL) 60 xtables_error(PARAMETER_PROBLEM, 61 "Newlines not allowed in --log-prefix"); 62 break; 63 } 64 } 65 66 static void NFLOG_check(struct xt_fcheck_call *cb) 67 { 68 struct xt_nflog_info *info = cb->data; 69 70 if (cb->xflags & F_RANGE) 71 fprintf(stderr, "warn: --nflog-range has never worked and is no" 72 " longer supported, please use --nflog-size insted\n"); 73 74 if (cb->xflags & F_SIZE) 75 info->flags |= XT_NFLOG_F_COPY_LEN; 76 } 77 78 static void nflog_print(const struct xt_nflog_info *info, char *prefix) 79 { 80 if (info->prefix[0] != '\0') { 81 printf(" %snflog-prefix ", prefix); 82 xtables_save_string(info->prefix); 83 } 84 if (info->group) 85 printf(" %snflog-group %u", prefix, info->group); 86 if (info->flags & XT_NFLOG_F_COPY_LEN) 87 printf(" %snflog-size %u", prefix, info->len); 88 else if (info->len) 89 printf(" %snflog-range %u", prefix, info->len); 90 if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD) 91 printf(" %snflog-threshold %u", prefix, info->threshold); 92 } 93 94 static void NFLOG_print(const void *ip, const struct xt_entry_target *target, 95 int numeric) 96 { 97 const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data; 98 99 nflog_print(info, ""); 100 } 101 102 static void NFLOG_save(const void *ip, const struct xt_entry_target *target) 103 { 104 const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data; 105 106 nflog_print(info, "--"); 107 } 108 109 static void nflog_print_xlate(const struct xt_nflog_info *info, 110 struct xt_xlate *xl, bool escape_quotes) 111 { 112 xt_xlate_add(xl, "log "); 113 if (info->prefix[0] != '\0') { 114 if (escape_quotes) 115 xt_xlate_add(xl, "prefix \\\"%s\\\" ", info->prefix); 116 else 117 xt_xlate_add(xl, "prefix \"%s\" ", info->prefix); 118 119 } 120 if (info->flags & XT_NFLOG_F_COPY_LEN) 121 xt_xlate_add(xl, "snaplen %u ", info->len); 122 if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD) 123 xt_xlate_add(xl, "queue-threshold %u ", info->threshold); 124 xt_xlate_add(xl, "group %u ", info->group); 125 } 126 127 static int NFLOG_xlate(struct xt_xlate *xl, 128 const struct xt_xlate_tg_params *params) 129 { 130 const struct xt_nflog_info *info = 131 (struct xt_nflog_info *)params->target->data; 132 133 nflog_print_xlate(info, xl, params->escape_quotes); 134 135 return 1; 136 } 137 138 static struct xtables_target nflog_target = { 139 .family = NFPROTO_UNSPEC, 140 .name = "NFLOG", 141 .version = XTABLES_VERSION, 142 .size = XT_ALIGN(sizeof(struct xt_nflog_info)), 143 .userspacesize = XT_ALIGN(sizeof(struct xt_nflog_info)), 144 .help = NFLOG_help, 145 .init = NFLOG_init, 146 .x6_fcheck = NFLOG_check, 147 .x6_parse = NFLOG_parse, 148 .print = NFLOG_print, 149 .save = NFLOG_save, 150 .x6_options = NFLOG_opts, 151 .xlate = NFLOG_xlate, 152 }; 153 154 void _init(void) 155 { 156 xtables_register_target(&nflog_target); 157 } 158
