diff options
Diffstat (limited to 'net/netfilter/nf_log_common.c')
-rw-r--r-- | net/netfilter/nf_log_common.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/net/netfilter/nf_log_common.c b/net/netfilter/nf_log_common.c new file mode 100644 index 000000000..a5aa5967b --- /dev/null +++ b/net/netfilter/nf_log_common.c @@ -0,0 +1,188 @@ +/* (C) 1999-2001 Paul `Rusty' Russell + * (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. + */ + +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/skbuff.h> +#include <linux/if_arp.h> +#include <linux/ip.h> +#include <net/icmp.h> +#include <net/udp.h> +#include <net/tcp.h> +#include <net/route.h> + +#include <linux/netfilter.h> +#include <linux/netfilter_bridge.h> +#include <linux/netfilter/xt_LOG.h> +#include <net/netfilter/nf_log.h> + +int nf_log_dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb, + u8 proto, int fragment, unsigned int offset) +{ + struct udphdr _udph; + const struct udphdr *uh; + + if (proto == IPPROTO_UDP) + /* Max length: 10 "PROTO=UDP " */ + nf_log_buf_add(m, "PROTO=UDP "); + else /* Max length: 14 "PROTO=UDPLITE " */ + nf_log_buf_add(m, "PROTO=UDPLITE "); + + if (fragment) + goto out; + + /* Max length: 25 "INCOMPLETE [65535 bytes] " */ + uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); + if (uh == NULL) { + nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset); + + return 1; + } + + /* Max length: 20 "SPT=65535 DPT=65535 " */ + nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ", + ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len)); + +out: + return 0; +} +EXPORT_SYMBOL_GPL(nf_log_dump_udp_header); + +int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb, + u8 proto, int fragment, unsigned int offset, + unsigned int logflags) +{ + struct tcphdr _tcph; + const struct tcphdr *th; + + /* Max length: 10 "PROTO=TCP " */ + nf_log_buf_add(m, "PROTO=TCP "); + + if (fragment) + return 0; + + /* Max length: 25 "INCOMPLETE [65535 bytes] " */ + th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); + if (th == NULL) { + nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset); + return 1; + } + + /* Max length: 20 "SPT=65535 DPT=65535 " */ + nf_log_buf_add(m, "SPT=%u DPT=%u ", + ntohs(th->source), ntohs(th->dest)); + /* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */ + if (logflags & XT_LOG_TCPSEQ) { + nf_log_buf_add(m, "SEQ=%u ACK=%u ", + ntohl(th->seq), ntohl(th->ack_seq)); + } + + /* Max length: 13 "WINDOW=65535 " */ + nf_log_buf_add(m, "WINDOW=%u ", ntohs(th->window)); + /* Max length: 9 "RES=0x3C " */ + nf_log_buf_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) + nf_log_buf_add(m, "CWR "); + if (th->ece) + nf_log_buf_add(m, "ECE "); + if (th->urg) + nf_log_buf_add(m, "URG "); + if (th->ack) + nf_log_buf_add(m, "ACK "); + if (th->psh) + nf_log_buf_add(m, "PSH "); + if (th->rst) + nf_log_buf_add(m, "RST "); + if (th->syn) + nf_log_buf_add(m, "SYN "); + if (th->fin) + nf_log_buf_add(m, "FIN "); + /* Max length: 11 "URGP=65535 " */ + nf_log_buf_add(m, "URGP=%u ", ntohs(th->urg_ptr)); + + if ((logflags & XT_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, offset + sizeof(struct tcphdr), + optsize, _opt); + if (op == NULL) { + nf_log_buf_add(m, "OPT (TRUNCATED)"); + return 1; + } + + /* Max length: 127 "OPT (" 15*4*2chars ") " */ + nf_log_buf_add(m, "OPT ("); + for (i = 0; i < optsize; i++) + nf_log_buf_add(m, "%02X", op[i]); + + nf_log_buf_add(m, ") "); + } + + return 0; +} +EXPORT_SYMBOL_GPL(nf_log_dump_tcp_header); + +void nf_log_dump_sk_uid_gid(struct nf_log_buf *m, struct sock *sk) +{ + if (!sk || !sk_fullsock(sk)) + return; + + read_lock_bh(&sk->sk_callback_lock); + if (sk->sk_socket && sk->sk_socket->file) { + const struct cred *cred = sk->sk_socket->file->f_cred; + nf_log_buf_add(m, "UID=%u GID=%u ", + from_kuid_munged(&init_user_ns, cred->fsuid), + from_kgid_munged(&init_user_ns, cred->fsgid)); + } + read_unlock_bh(&sk->sk_callback_lock); +} +EXPORT_SYMBOL_GPL(nf_log_dump_sk_uid_gid); + +void +nf_log_dump_packet_common(struct nf_log_buf *m, 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) +{ + nf_log_buf_add(m, KERN_SOH "%c%sIN=%s OUT=%s ", + '0' + loginfo->u.log.level, prefix, + in ? in->name : "", + out ? out->name : ""); +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + if (skb->nf_bridge) { + const struct net_device *physindev; + const struct net_device *physoutdev; + + physindev = nf_bridge_get_physindev(skb); + if (physindev && in != physindev) + nf_log_buf_add(m, "PHYSIN=%s ", physindev->name); + physoutdev = nf_bridge_get_physoutdev(skb); + if (physoutdev && out != physoutdev) + nf_log_buf_add(m, "PHYSOUT=%s ", physoutdev->name); + } +#endif +} +EXPORT_SYMBOL_GPL(nf_log_dump_packet_common); + +static int __init nf_log_common_init(void) +{ + return 0; +} + +static void __exit nf_log_common_exit(void) {} + +module_init(nf_log_common_init); +module_exit(nf_log_common_exit); + +MODULE_LICENSE("GPL"); |