-/* Shared library add-on to iptables to add LOG support. */
-#include <stdio.h>
-#include <netdb.h>
-#include <string.h>
-#include <stdlib.h>
-#include <syslog.h>
-#include <getopt.h>
-#include <iptables.h>
-#include <linux/netfilter_ipv4/ip_tables.h>
-#include <linux/netfilter_ipv4/ipt_LOG.h>
-
-#define LOG_DEFAULT_LEVEL LOG_WARNING
-
-#ifndef IPT_LOG_UID /* Old kernel */
-#define IPT_LOG_UID 0x08 /* Log UID owning local socket */
-#undef IPT_LOG_MASK
-#define IPT_LOG_MASK 0x0f
-#endif
-
-/* Function which prints out usage message. */
-static void LOG_help(void)
-{
- printf(
-"LOG target options:\n"
-" --log-level level Level of logging (numeric or see syslog.conf)\n"
-" --log-prefix prefix Prefix log messages with this prefix.\n\n"
-" --log-tcp-sequence Log TCP sequence numbers.\n\n"
-" --log-tcp-options Log TCP options.\n\n"
-" --log-ip-options Log IP options.\n\n"
-" --log-uid Log UID owning the local socket.\n\n");
-}
-
-static const struct option LOG_opts[] = {
- { .name = "log-level", .has_arg = 1, .val = '!' },
- { .name = "log-prefix", .has_arg = 1, .val = '#' },
- { .name = "log-tcp-sequence", .has_arg = 0, .val = '1' },
- { .name = "log-tcp-options", .has_arg = 0, .val = '2' },
- { .name = "log-ip-options", .has_arg = 0, .val = '3' },
- { .name = "log-uid", .has_arg = 0, .val = '4' },
- { .name = NULL }
-};
-
-/* Initialize the target. */
-static void LOG_init(struct xt_entry_target *t)
-{
- struct ipt_log_info *loginfo = (struct ipt_log_info *)t->data;
-
- loginfo->level = LOG_DEFAULT_LEVEL;
-
-}
-
-struct ipt_log_names {
- const char *name;
- unsigned int level;
-};
-
-static const struct ipt_log_names ipt_log_names[]
-= { { .name = "alert", .level = LOG_ALERT },
- { .name = "crit", .level = LOG_CRIT },
- { .name = "debug", .level = LOG_DEBUG },
- { .name = "emerg", .level = LOG_EMERG },
- { .name = "error", .level = LOG_ERR }, /* DEPRECATED */
- { .name = "info", .level = LOG_INFO },
- { .name = "notice", .level = LOG_NOTICE },
- { .name = "panic", .level = LOG_EMERG }, /* DEPRECATED */
- { .name = "warning", .level = LOG_WARNING }
-};
-
-static u_int8_t
-parse_level(const char *level)
-{
- unsigned int lev = -1;
- unsigned int set = 0;
-
- if (string_to_number(level, 0, 7, &lev) == -1) {
- unsigned int i = 0;
-
- for (i = 0;
- i < sizeof(ipt_log_names) / sizeof(struct ipt_log_names);
- i++) {
- if (strncasecmp(level, ipt_log_names[i].name,
- strlen(level)) == 0) {
- if (set++)
- exit_error(PARAMETER_PROBLEM,
- "log-level `%s' ambiguous",
- level);
- lev = ipt_log_names[i].level;
- }
- }
-
- if (!set)
- exit_error(PARAMETER_PROBLEM,
- "log-level `%s' unknown", level);
- }
-
- return (u_int8_t)lev;
-}
-
-#define IPT_LOG_OPT_LEVEL 0x01
-#define IPT_LOG_OPT_PREFIX 0x02
-#define IPT_LOG_OPT_TCPSEQ 0x04
-#define IPT_LOG_OPT_TCPOPT 0x08
-#define IPT_LOG_OPT_IPOPT 0x10
-#define IPT_LOG_OPT_UID 0x20
-
-/* Function which parses command options; returns true if it
- ate an option */
-static int LOG_parse(int c, char **argv, int invert, unsigned int *flags,
- const void *entry, struct xt_entry_target **target)
-{
- struct ipt_log_info *loginfo = (struct ipt_log_info *)(*target)->data;
-
- switch (c) {
- case '!':
- if (*flags & IPT_LOG_OPT_LEVEL)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify --log-level twice");
-
- if (check_inverse(optarg, &invert, NULL, 0))
- exit_error(PARAMETER_PROBLEM,
- "Unexpected `!' after --log-level");
-
- loginfo->level = parse_level(optarg);
- *flags |= IPT_LOG_OPT_LEVEL;
- break;
-
- case '#':
- if (*flags & IPT_LOG_OPT_PREFIX)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify --log-prefix twice");
-
- if (check_inverse(optarg, &invert, NULL, 0))
- exit_error(PARAMETER_PROBLEM,
- "Unexpected `!' after --log-prefix");
-
- if (strlen(optarg) > sizeof(loginfo->prefix) - 1)
- exit_error(PARAMETER_PROBLEM,
- "Maximum prefix length %u for --log-prefix",
- (unsigned int)sizeof(loginfo->prefix) - 1);
-
- if (strlen(optarg) == 0)
- exit_error(PARAMETER_PROBLEM,
- "No prefix specified for --log-prefix");
-
- if (strlen(optarg) != strlen(strtok(optarg, "\n")))
- exit_error(PARAMETER_PROBLEM,
- "Newlines not allowed in --log-prefix");
-
- strcpy(loginfo->prefix, optarg);
- *flags |= IPT_LOG_OPT_PREFIX;
- break;
-
- case '1':
- if (*flags & IPT_LOG_OPT_TCPSEQ)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify --log-tcp-sequence "
- "twice");
-
- loginfo->logflags |= IPT_LOG_TCPSEQ;
- *flags |= IPT_LOG_OPT_TCPSEQ;
- break;
-
- case '2':
- if (*flags & IPT_LOG_OPT_TCPOPT)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify --log-tcp-options twice");
-
- loginfo->logflags |= IPT_LOG_TCPOPT;
- *flags |= IPT_LOG_OPT_TCPOPT;
- break;
-
- case '3':
- if (*flags & IPT_LOG_OPT_IPOPT)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify --log-ip-options twice");
-
- loginfo->logflags |= IPT_LOG_IPOPT;
- *flags |= IPT_LOG_OPT_IPOPT;
- break;
-
- case '4':
- if (*flags & IPT_LOG_OPT_UID)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify --log-uid twice");
-
- loginfo->logflags |= IPT_LOG_UID;
- *flags |= IPT_LOG_OPT_UID;
- break;
-
- default:
- return 0;
- }
-
- return 1;
-}
-
-/* Prints out the targinfo. */
-static void LOG_print(const void *ip, const struct xt_entry_target *target,
- int numeric)
-{
- const struct ipt_log_info *loginfo
- = (const struct ipt_log_info *)target->data;
- unsigned int i = 0;
-
- printf("LOG ");
- if (numeric)
- printf("flags %u level %u ",
- loginfo->logflags, loginfo->level);
- else {
- for (i = 0;
- i < sizeof(ipt_log_names) / sizeof(struct ipt_log_names);
- i++) {
- if (loginfo->level == ipt_log_names[i].level) {
- printf("level %s ", ipt_log_names[i].name);
- break;
- }
- }
- if (i == sizeof(ipt_log_names) / sizeof(struct ipt_log_names))
- printf("UNKNOWN level %u ", loginfo->level);
- if (loginfo->logflags & IPT_LOG_TCPSEQ)
- printf("tcp-sequence ");
- if (loginfo->logflags & IPT_LOG_TCPOPT)
- printf("tcp-options ");
- if (loginfo->logflags & IPT_LOG_IPOPT)
- printf("ip-options ");
- if (loginfo->logflags & IPT_LOG_UID)
- printf("uid ");
- if (loginfo->logflags & ~(IPT_LOG_MASK))
- printf("unknown-flags ");
- }
-
- if (strcmp(loginfo->prefix, "") != 0)
- printf("prefix `%s' ", loginfo->prefix);
-}
-
-/* Saves the union ipt_targinfo in parsable form to stdout. */
-static void LOG_save(const void *ip, const struct xt_entry_target *target)
-{
- const struct ipt_log_info *loginfo
- = (const struct ipt_log_info *)target->data;
-
- if (strcmp(loginfo->prefix, "") != 0) {
- printf("--log-prefix ");
- save_string(loginfo->prefix);
- }
-
- if (loginfo->level != LOG_DEFAULT_LEVEL)
- printf("--log-level %d ", loginfo->level);
-
- if (loginfo->logflags & IPT_LOG_TCPSEQ)
- printf("--log-tcp-sequence ");
- if (loginfo->logflags & IPT_LOG_TCPOPT)
- printf("--log-tcp-options ");
- if (loginfo->logflags & IPT_LOG_IPOPT)
- printf("--log-ip-options ");
- if (loginfo->logflags & IPT_LOG_UID)
- printf("--log-uid ");
-}
-
-static struct xtables_target log_tg_reg = {
- .name = "LOG",
- .version = XTABLES_VERSION,
- .family = PF_INET,
- .size = XT_ALIGN(sizeof(struct ipt_log_info)),
- .userspacesize = XT_ALIGN(sizeof(struct ipt_log_info)),
- .help = LOG_help,
- .init = LOG_init,
- .parse = LOG_parse,
- .print = LOG_print,
- .save = LOG_save,
- .extra_opts = LOG_opts,
-};
-
-void _init(void)
-{
- xtables_register_target(&log_tg_reg);
-}