From: Richard Weinberger <richard@xxxxxx> Signed-off-by: Richard Weinberger <richard@xxxxxx> --- extensions/libxt_RLOG.c | 171 +++++++++++++++++++++++++++++++++++++++++++++ extensions/libxt_RLOG.man | 17 +++++ 2 files changed, 188 insertions(+), 0 deletions(-) create mode 100644 extensions/libxt_RLOG.c create mode 100644 extensions/libxt_RLOG.man diff --git a/extensions/libxt_RLOG.c b/extensions/libxt_RLOG.c new file mode 100644 index 0000000..1a7d697 --- /dev/null +++ b/extensions/libxt_RLOG.c @@ -0,0 +1,171 @@ +#include <stdio.h> +#include <string.h> +#include <ctype.h> +#include <xtables.h> +#include <linux/netfilter_ipv4/ipt_LOG.h> + +#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 + +#define RING_NAME_LEN 32 +#define DEFAULT_RING_SIZE 1024 /* in KiB */ +#define DEFAULT_RING_NAME "default" + +struct rlog_tg_info { + char name[RING_NAME_LEN]; + unsigned int size; + unsigned char logflags; + bool add_timestamp; +}; + +enum { + O_RLOG_RING_SIZE = 0, + O_RLOG_RING, + O_LOG_TCPSEQ, + O_LOG_TCPOPTS, + O_LOG_IPOPTS, + O_LOG_UID, + O_LOG_MAC, + O_ADD_TS +}; + +static void RLOG_help(void) +{ + printf( +"RLOG target options:\n" +" --ring NAME Log messages into NAME.\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" +" --log-macdecode Decode MAC addresses and protocol.\n\n" +" --add-timestamp Add a timestamp to each log message.\n\n"); +} + +#define s struct rlog_tg_info +static const struct xt_option_entry RLOG_opts[] = { + {.name = "size", .id = O_RLOG_RING_SIZE, .type = XTTYPE_UINT32, + .flags = XTOPT_PUT, XTOPT_POINTER(s, size)}, + {.name = "ring", .id = O_RLOG_RING, .type = XTTYPE_STRING, + .flags = XTOPT_PUT, XTOPT_POINTER(s, name), .min = 1, .max = RING_NAME_LEN}, + {.name = "log-tcp-sequence", .id = O_LOG_TCPSEQ, .type = XTTYPE_NONE}, + {.name = "log-tcp-options", .id = O_LOG_TCPOPTS, .type = XTTYPE_NONE}, + {.name = "log-ip-options", .id = O_LOG_IPOPTS, .type = XTTYPE_NONE}, + {.name = "log-uid", .id = O_LOG_UID, .type = XTTYPE_NONE}, + {.name = "log-macdecode", .id = O_LOG_MAC, .type = XTTYPE_NONE}, + {.name = "add-timestamp", .id = O_ADD_TS, .type = XTTYPE_NONE}, + XTOPT_TABLEEND, +}; +#undef s + +static void RLOG_init(struct xt_entry_target *t) +{ + struct rlog_tg_info *info = (struct rlog_tg_info *)t->data; + + info->size = DEFAULT_RING_SIZE; + strcpy(info->name, DEFAULT_RING_NAME); + info->add_timestamp = false; + info->logflags = 0; +} + +static void RLOG_parse(struct xt_option_call *cb) +{ + struct rlog_tg_info *info = cb->data; + int len, i; + + xtables_option_parse(cb); + switch (cb->entry->id) { + case O_RLOG_RING: + len = strlen(cb->arg); + + for (i = 0; i < len; i++) + if (!isalnum(cb->arg[i])) + xtables_error(PARAMETER_PROBLEM, "--ring allows only alphanumeric names!\n"); + break; + case O_LOG_TCPSEQ: + info->logflags |= IPT_LOG_TCPSEQ; + break; + case O_LOG_TCPOPTS: + info->logflags |= IPT_LOG_TCPOPT; + break; + case O_LOG_IPOPTS: + info->logflags |= IPT_LOG_IPOPT; + break; + case O_LOG_UID: + info->logflags |= IPT_LOG_UID; + break; + case O_LOG_MAC: + info->logflags |= IPT_LOG_MACDECODE; + break; + case O_ADD_TS: + info->add_timestamp = true; + break; + } +} + +static void RLOG_save(const void *ip, const struct xt_entry_target *target) +{ + const struct rlog_tg_info *info + = (const struct rlog_tg_info *)target->data; + + if (strcmp(info->name, DEFAULT_RING_NAME) != 0) + printf(" --ring %s", info->name); + if (info->size != DEFAULT_RING_SIZE) + printf(" --size %u", info->size); + if (info->logflags & IPT_LOG_TCPSEQ) + printf(" --log-tcp-sequence"); + if (info->logflags & IPT_LOG_TCPOPT) + printf(" --log-tcp-options"); + if (info->logflags & IPT_LOG_IPOPT) + printf(" --log-ip-options"); + if (info->logflags & IPT_LOG_UID) + printf(" --log-uid"); + if (info->logflags & IPT_LOG_MACDECODE) + printf(" --log-macdecode"); + if (info->add_timestamp) + printf(" --add-timestamp"); +} + +static void RLOG_print(const void *ip, const struct xt_entry_target *target, + int numeric) +{ + printf(" RLOG"); + RLOG_save(ip, target); +} + +static struct xtables_target rlog_tg_regs[] = { + { + .name = "RLOG", + .version = XTABLES_VERSION, + .family = NFPROTO_IPV4, + .size = XT_ALIGN(sizeof(struct rlog_tg_info) + sizeof (void *)), + .userspacesize = XT_ALIGN(sizeof(struct rlog_tg_info)), + .help = RLOG_help, + .init = RLOG_init, + .print = RLOG_print, + .save = RLOG_save, + .x6_parse = RLOG_parse, + .x6_options = RLOG_opts, + }, + { + .name = "RLOG", + .version = XTABLES_VERSION, + .family = NFPROTO_IPV6, + .size = XT_ALIGN(sizeof(struct rlog_tg_info) + sizeof (void *)), + .userspacesize = XT_ALIGN(sizeof(struct rlog_tg_info)), + .help = RLOG_help, + .init = RLOG_init, + .print = RLOG_print, + .save = RLOG_save, + .x6_parse = RLOG_parse, + .x6_options = RLOG_opts, + } +}; + +void _init(void) +{ + xtables_register_targets(rlog_tg_regs, ARRAY_SIZE(rlog_tg_regs)); +} diff --git a/extensions/libxt_RLOG.man b/extensions/libxt_RLOG.man new file mode 100644 index 0000000..184c779 --- /dev/null +++ b/extensions/libxt_RLOG.man @@ -0,0 +1,17 @@ +Turn on kernel logging of matching packets. This target generates +messages like LOG but instead of writing them into the kernel +syslog it writes them info one or more ring buffers +Each ring buffer is represented as a file in +/proc/net/netfilter/xt_RLOG/. +.TP +\fB\-\-ring\fP \fIname\fP +Write messages into ring buffer \fIname\fP. +.TP +\fB\-\-ring\fP \fIN\fP +Make the ring buffer \fIN\fP KiB long. +.TP +\fB\-\-log\-tcp\-sequence\fP +\fB\-\-log\-tcp\-options\fP +\fB\-\-log\-ip\-options\fP +\fB\-\-log\-uid\fP +See LOG. -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html