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path: root/net/ipv6/netfilter/ip6t_LOG.c
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Diffstat (limited to 'net/ipv6/netfilter/ip6t_LOG.c')
-rw-r--r--net/ipv6/netfilter/ip6t_LOG.c527
1 files changed, 527 insertions, 0 deletions
diff --git a/net/ipv6/netfilter/ip6t_LOG.c b/net/ipv6/netfilter/ip6t_LOG.c
new file mode 100644
index 00000000..e6af8d72
--- /dev/null
+++ b/net/ipv6/netfilter/ip6t_LOG.c
@@ -0,0 +1,527 @@
+/*
+ * This is a module which is used for logging packets.
+ */
+
+/* (C) 2001 Jan Rekorajski <baggins@pld.org.pl>
+ * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/if_arp.h>
+#include <linux/ip.h>
+#include <linux/spinlock.h>
+#include <linux/icmpv6.h>
+#include <net/udp.h>
+#include <net/tcp.h>
+#include <net/ipv6.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
+#include <net/netfilter/nf_log.h>
+#include <net/netfilter/xt_log.h>
+
+MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");
+MODULE_DESCRIPTION("Xtables: IPv6 packet logging to syslog");
+MODULE_LICENSE("GPL");
+
+struct in_device;
+#include <net/route.h>
+#include <linux/netfilter_ipv6/ip6t_LOG.h>
+
+/* One level of recursion won't kill us */
+static void dump_packet(struct sbuff *m,
+ const struct nf_loginfo *info,
+ const struct sk_buff *skb, unsigned int ip6hoff,
+ int recurse)
+{
+ u_int8_t currenthdr;
+ int fragment;
+ struct ipv6hdr _ip6h;
+ const struct ipv6hdr *ih;
+ unsigned int ptr;
+ unsigned int hdrlen = 0;
+ unsigned int logflags;
+
+ if (info->type == NF_LOG_TYPE_LOG)
+ logflags = info->u.log.logflags;
+ else
+ logflags = NF_LOG_MASK;
+
+ ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h);
+ if (ih == NULL) {
+ sb_add(m, "TRUNCATED");
+ return;
+ }
+
+ /* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
+ sb_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);
+
+ /* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
+ sb_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
+ ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
+ (ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20,
+ ih->hop_limit,
+ (ntohl(*(__be32 *)ih) & 0x000fffff));
+
+ fragment = 0;
+ ptr = ip6hoff + sizeof(struct ipv6hdr);
+ currenthdr = ih->nexthdr;
+ while (currenthdr != NEXTHDR_NONE && ip6t_ext_hdr(currenthdr)) {
+ struct ipv6_opt_hdr _hdr;
+ const struct ipv6_opt_hdr *hp;
+
+ hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
+ if (hp == NULL) {
+ sb_add(m, "TRUNCATED");
+ return;
+ }
+
+ /* Max length: 48 "OPT (...) " */
+ if (logflags & IP6T_LOG_IPOPT)
+ sb_add(m, "OPT ( ");
+
+ switch (currenthdr) {
+ case IPPROTO_FRAGMENT: {
+ struct frag_hdr _fhdr;
+ const struct frag_hdr *fh;
+
+ sb_add(m, "FRAG:");
+ fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
+ &_fhdr);
+ if (fh == NULL) {
+ sb_add(m, "TRUNCATED ");
+ return;
+ }
+
+ /* Max length: 6 "65535 " */
+ sb_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);
+
+ /* Max length: 11 "INCOMPLETE " */
+ if (fh->frag_off & htons(0x0001))
+ sb_add(m, "INCOMPLETE ");
+
+ sb_add(m, "ID:%08x ", ntohl(fh->identification));
+
+ if (ntohs(fh->frag_off) & 0xFFF8)
+ fragment = 1;
+
+ hdrlen = 8;
+
+ break;
+ }
+ case IPPROTO_DSTOPTS:
+ case IPPROTO_ROUTING:
+ case IPPROTO_HOPOPTS:
+ if (fragment) {
+ if (logflags & IP6T_LOG_IPOPT)
+ sb_add(m, ")");
+ return;
+ }
+ hdrlen = ipv6_optlen(hp);
+ break;
+ /* Max Length */
+ case IPPROTO_AH:
+ if (logflags & IP6T_LOG_IPOPT) {
+ struct ip_auth_hdr _ahdr;
+ const struct ip_auth_hdr *ah;
+
+ /* Max length: 3 "AH " */
+ sb_add(m, "AH ");
+
+ if (fragment) {
+ sb_add(m, ")");
+ return;
+ }
+
+ ah = skb_header_pointer(skb, ptr, sizeof(_ahdr),
+ &_ahdr);
+ if (ah == NULL) {
+ /*
+ * Max length: 26 "INCOMPLETE [65535
+ * bytes] )"
+ */
+ sb_add(m, "INCOMPLETE [%u bytes] )",
+ skb->len - ptr);
+ return;
+ }
+
+ /* Length: 15 "SPI=0xF1234567 */
+ sb_add(m, "SPI=0x%x ", ntohl(ah->spi));
+
+ }
+
+ hdrlen = (hp->hdrlen+2)<<2;
+ break;
+ case IPPROTO_ESP:
+ if (logflags & IP6T_LOG_IPOPT) {
+ struct ip_esp_hdr _esph;
+ const struct ip_esp_hdr *eh;
+
+ /* Max length: 4 "ESP " */
+ sb_add(m, "ESP ");
+
+ if (fragment) {
+ sb_add(m, ")");
+ return;
+ }
+
+ /*
+ * Max length: 26 "INCOMPLETE [65535 bytes] )"
+ */
+ eh = skb_header_pointer(skb, ptr, sizeof(_esph),
+ &_esph);
+ if (eh == NULL) {
+ sb_add(m, "INCOMPLETE [%u bytes] )",
+ skb->len - ptr);
+ return;
+ }
+
+ /* Length: 16 "SPI=0xF1234567 )" */
+ sb_add(m, "SPI=0x%x )", ntohl(eh->spi) );
+
+ }
+ return;
+ default:
+ /* Max length: 20 "Unknown Ext Hdr 255" */
+ sb_add(m, "Unknown Ext Hdr %u", currenthdr);
+ return;
+ }
+ if (logflags & IP6T_LOG_IPOPT)
+ sb_add(m, ") ");
+
+ currenthdr = hp->nexthdr;
+ ptr += hdrlen;
+ }
+
+ switch (currenthdr) {
+ case IPPROTO_TCP: {
+ struct tcphdr _tcph;
+ const struct tcphdr *th;
+
+ /* Max length: 10 "PROTO=TCP " */
+ sb_add(m, "PROTO=TCP ");
+
+ if (fragment)
+ break;
+
+ /* Max length: 25 "INCOMPLETE [65535 bytes] " */
+ th = skb_header_pointer(skb, ptr, sizeof(_tcph), &_tcph);
+ if (th == NULL) {
+ sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
+ return;
+ }
+
+ /* Max length: 20 "SPT=65535 DPT=65535 " */
+ sb_add(m, "SPT=%u DPT=%u ",
+ ntohs(th->source), ntohs(th->dest));
+ /* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
+ if (logflags & IP6T_LOG_TCPSEQ)
+ sb_add(m, "SEQ=%u ACK=%u ",
+ ntohl(th->seq), ntohl(th->ack_seq));
+ /* Max length: 13 "WINDOW=65535 " */
+ sb_add(m, "WINDOW=%u ", ntohs(th->window));
+ /* Max length: 9 "RES=0x3C " */
+ sb_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) & TCP_RESERVED_BITS) >> 22));
+ /* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
+ if (th->cwr)
+ sb_add(m, "CWR ");
+ if (th->ece)
+ sb_add(m, "ECE ");
+ if (th->urg)
+ sb_add(m, "URG ");
+ if (th->ack)
+ sb_add(m, "ACK ");
+ if (th->psh)
+ sb_add(m, "PSH ");
+ if (th->rst)
+ sb_add(m, "RST ");
+ if (th->syn)
+ sb_add(m, "SYN ");
+ if (th->fin)
+ sb_add(m, "FIN ");
+ /* Max length: 11 "URGP=65535 " */
+ sb_add(m, "URGP=%u ", ntohs(th->urg_ptr));
+
+ if ((logflags & IP6T_LOG_TCPOPT) &&
+ th->doff * 4 > sizeof(struct tcphdr)) {
+ u_int8_t _opt[60 - sizeof(struct tcphdr)];
+ const u_int8_t *op;
+ unsigned int i;
+ unsigned int optsize = th->doff * 4
+ - sizeof(struct tcphdr);
+
+ op = skb_header_pointer(skb,
+ ptr + sizeof(struct tcphdr),
+ optsize, _opt);
+ if (op == NULL) {
+ sb_add(m, "OPT (TRUNCATED)");
+ return;
+ }
+
+ /* Max length: 127 "OPT (" 15*4*2chars ") " */
+ sb_add(m, "OPT (");
+ for (i =0; i < optsize; i++)
+ sb_add(m, "%02X", op[i]);
+ sb_add(m, ") ");
+ }
+ break;
+ }
+ case IPPROTO_UDP:
+ case IPPROTO_UDPLITE: {
+ struct udphdr _udph;
+ const struct udphdr *uh;
+
+ if (currenthdr == IPPROTO_UDP)
+ /* Max length: 10 "PROTO=UDP " */
+ sb_add(m, "PROTO=UDP " );
+ else /* Max length: 14 "PROTO=UDPLITE " */
+ sb_add(m, "PROTO=UDPLITE ");
+
+ if (fragment)
+ break;
+
+ /* Max length: 25 "INCOMPLETE [65535 bytes] " */
+ uh = skb_header_pointer(skb, ptr, sizeof(_udph), &_udph);
+ if (uh == NULL) {
+ sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
+ return;
+ }
+
+ /* Max length: 20 "SPT=65535 DPT=65535 " */
+ sb_add(m, "SPT=%u DPT=%u LEN=%u ",
+ ntohs(uh->source), ntohs(uh->dest),
+ ntohs(uh->len));
+ break;
+ }
+ case IPPROTO_ICMPV6: {
+ struct icmp6hdr _icmp6h;
+ const struct icmp6hdr *ic;
+
+ /* Max length: 13 "PROTO=ICMPv6 " */
+ sb_add(m, "PROTO=ICMPv6 ");
+
+ if (fragment)
+ break;
+
+ /* Max length: 25 "INCOMPLETE [65535 bytes] " */
+ ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
+ if (ic == NULL) {
+ sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
+ return;
+ }
+
+ /* Max length: 18 "TYPE=255 CODE=255 " */
+ sb_add(m, "TYPE=%u CODE=%u ", ic->icmp6_type, ic->icmp6_code);
+
+ switch (ic->icmp6_type) {
+ case ICMPV6_ECHO_REQUEST:
+ case ICMPV6_ECHO_REPLY:
+ /* Max length: 19 "ID=65535 SEQ=65535 " */
+ sb_add(m, "ID=%u SEQ=%u ",
+ ntohs(ic->icmp6_identifier),
+ ntohs(ic->icmp6_sequence));
+ break;
+ case ICMPV6_MGM_QUERY:
+ case ICMPV6_MGM_REPORT:
+ case ICMPV6_MGM_REDUCTION:
+ break;
+
+ case ICMPV6_PARAMPROB:
+ /* Max length: 17 "POINTER=ffffffff " */
+ sb_add(m, "POINTER=%08x ", ntohl(ic->icmp6_pointer));
+ /* Fall through */
+ case ICMPV6_DEST_UNREACH:
+ case ICMPV6_PKT_TOOBIG:
+ case ICMPV6_TIME_EXCEED:
+ /* Max length: 3+maxlen */
+ if (recurse) {
+ sb_add(m, "[");
+ dump_packet(m, info, skb,
+ ptr + sizeof(_icmp6h), 0);
+ sb_add(m, "] ");
+ }
+
+ /* Max length: 10 "MTU=65535 " */
+ if (ic->icmp6_type == ICMPV6_PKT_TOOBIG)
+ sb_add(m, "MTU=%u ", ntohl(ic->icmp6_mtu));
+ }
+ break;
+ }
+ /* Max length: 10 "PROTO=255 " */
+ default:
+ sb_add(m, "PROTO=%u ", currenthdr);
+ }
+
+ /* Max length: 15 "UID=4294967295 " */
+ if ((logflags & IP6T_LOG_UID) && recurse && skb->sk) {
+ read_lock_bh(&skb->sk->sk_callback_lock);
+ if (skb->sk->sk_socket && skb->sk->sk_socket->file)
+ sb_add(m, "UID=%u GID=%u ",
+ skb->sk->sk_socket->file->f_cred->fsuid,
+ skb->sk->sk_socket->file->f_cred->fsgid);
+ read_unlock_bh(&skb->sk->sk_callback_lock);
+ }
+
+ /* Max length: 16 "MARK=0xFFFFFFFF " */
+ if (!recurse && skb->mark)
+ sb_add(m, "MARK=0x%x ", skb->mark);
+}
+
+static void dump_mac_header(struct sbuff *m,
+ const struct nf_loginfo *info,
+ const struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+ unsigned int logflags = 0;
+
+ if (info->type == NF_LOG_TYPE_LOG)
+ logflags = info->u.log.logflags;
+
+ if (!(logflags & IP6T_LOG_MACDECODE))
+ goto fallback;
+
+ switch (dev->type) {
+ case ARPHRD_ETHER:
+ sb_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
+ eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
+ ntohs(eth_hdr(skb)->h_proto));
+ return;
+ default:
+ break;
+ }
+
+fallback:
+ sb_add(m, "MAC=");
+ if (dev->hard_header_len &&
+ skb->mac_header != skb->network_header) {
+ const unsigned char *p = skb_mac_header(skb);
+ unsigned int len = dev->hard_header_len;
+ unsigned int i;
+
+ if (dev->type == ARPHRD_SIT &&
+ (p -= ETH_HLEN) < skb->head)
+ p = NULL;
+
+ if (p != NULL) {
+ sb_add(m, "%02x", *p++);
+ for (i = 1; i < len; i++)
+ sb_add(m, ":%02x", *p++);
+ }
+ sb_add(m, " ");
+
+ if (dev->type == ARPHRD_SIT) {
+ const struct iphdr *iph =
+ (struct iphdr *)skb_mac_header(skb);
+ sb_add(m, "TUNNEL=%pI4->%pI4 ", &iph->saddr, &iph->daddr);
+ }
+ } else
+ sb_add(m, " ");
+}
+
+static struct nf_loginfo default_loginfo = {
+ .type = NF_LOG_TYPE_LOG,
+ .u = {
+ .log = {
+ .level = 5,
+ .logflags = NF_LOG_MASK,
+ },
+ },
+};
+
+static void
+ip6t_log_packet(u_int8_t pf,
+ unsigned int hooknum,
+ const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ const struct nf_loginfo *loginfo,
+ const char *prefix)
+{
+ struct sbuff *m = sb_open();
+
+ if (!loginfo)
+ loginfo = &default_loginfo;
+
+ sb_add(m, "<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
+ prefix,
+ in ? in->name : "",
+ out ? out->name : "");
+
+ if (in != NULL)
+ dump_mac_header(m, loginfo, skb);
+
+ dump_packet(m, loginfo, skb, skb_network_offset(skb), 1);
+
+ sb_close(m);
+}
+
+static unsigned int
+log_tg6(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct ip6t_log_info *loginfo = par->targinfo;
+ struct nf_loginfo li;
+
+ li.type = NF_LOG_TYPE_LOG;
+ li.u.log.level = loginfo->level;
+ li.u.log.logflags = loginfo->logflags;
+
+ ip6t_log_packet(NFPROTO_IPV6, par->hooknum, skb, par->in, par->out,
+ &li, loginfo->prefix);
+ return XT_CONTINUE;
+}
+
+
+static int log_tg6_check(const struct xt_tgchk_param *par)
+{
+ const struct ip6t_log_info *loginfo = par->targinfo;
+
+ if (loginfo->level >= 8) {
+ pr_debug("level %u >= 8\n", loginfo->level);
+ return -EINVAL;
+ }
+ if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') {
+ pr_debug("prefix not null-terminated\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct xt_target log_tg6_reg __read_mostly = {
+ .name = "LOG",
+ .family = NFPROTO_IPV6,
+ .target = log_tg6,
+ .targetsize = sizeof(struct ip6t_log_info),
+ .checkentry = log_tg6_check,
+ .me = THIS_MODULE,
+};
+
+static struct nf_logger ip6t_logger __read_mostly = {
+ .name = "ip6t_LOG",
+ .logfn = &ip6t_log_packet,
+ .me = THIS_MODULE,
+};
+
+static int __init log_tg6_init(void)
+{
+ int ret;
+
+ ret = xt_register_target(&log_tg6_reg);
+ if (ret < 0)
+ return ret;
+ nf_log_register(NFPROTO_IPV6, &ip6t_logger);
+ return 0;
+}
+
+static void __exit log_tg6_exit(void)
+{
+ nf_log_unregister(&ip6t_logger);
+ xt_unregister_target(&log_tg6_reg);
+}
+
+module_init(log_tg6_init);
+module_exit(log_tg6_exit);
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 08:43:48 +0000