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9#include <linux/module.h>
10#include <linux/spinlock.h>
11#include <linux/skbuff.h>
12#include <linux/if_arp.h>
13#include <linux/ip.h>
14#include <net/icmp.h>
15#include <net/udp.h>
16#include <net/tcp.h>
17#include <net/route.h>
18
19#include <linux/netfilter.h>
20#include <linux/netfilter_bridge.h>
21#include <linux/netfilter/xt_LOG.h>
22#include <net/netfilter/nf_log.h>
23
24int nf_log_dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb,
25 u8 proto, int fragment, unsigned int offset)
26{
27 struct udphdr _udph;
28 const struct udphdr *uh;
29
30 if (proto == IPPROTO_UDP)
31
32 nf_log_buf_add(m, "PROTO=UDP ");
33 else
34 nf_log_buf_add(m, "PROTO=UDPLITE ");
35
36 if (fragment)
37 goto out;
38
39
40 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
41 if (uh == NULL) {
42 nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
43
44 return 1;
45 }
46
47
48 nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ",
49 ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
50
51out:
52 return 0;
53}
54EXPORT_SYMBOL_GPL(nf_log_dump_udp_header);
55
56int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
57 u8 proto, int fragment, unsigned int offset,
58 unsigned int logflags)
59{
60 struct tcphdr _tcph;
61 const struct tcphdr *th;
62
63
64 nf_log_buf_add(m, "PROTO=TCP ");
65
66 if (fragment)
67 return 0;
68
69
70 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
71 if (th == NULL) {
72 nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
73 return 1;
74 }
75
76
77 nf_log_buf_add(m, "SPT=%u DPT=%u ",
78 ntohs(th->source), ntohs(th->dest));
79
80 if (logflags & NF_LOG_TCPSEQ) {
81 nf_log_buf_add(m, "SEQ=%u ACK=%u ",
82 ntohl(th->seq), ntohl(th->ack_seq));
83 }
84
85
86 nf_log_buf_add(m, "WINDOW=%u ", ntohs(th->window));
87
88 nf_log_buf_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) &
89 TCP_RESERVED_BITS) >> 22));
90
91 if (th->cwr)
92 nf_log_buf_add(m, "CWR ");
93 if (th->ece)
94 nf_log_buf_add(m, "ECE ");
95 if (th->urg)
96 nf_log_buf_add(m, "URG ");
97 if (th->ack)
98 nf_log_buf_add(m, "ACK ");
99 if (th->psh)
100 nf_log_buf_add(m, "PSH ");
101 if (th->rst)
102 nf_log_buf_add(m, "RST ");
103 if (th->syn)
104 nf_log_buf_add(m, "SYN ");
105 if (th->fin)
106 nf_log_buf_add(m, "FIN ");
107
108 nf_log_buf_add(m, "URGP=%u ", ntohs(th->urg_ptr));
109
110 if ((logflags & NF_LOG_TCPOPT) && th->doff*4 > sizeof(struct tcphdr)) {
111 u_int8_t _opt[60 - sizeof(struct tcphdr)];
112 const u_int8_t *op;
113 unsigned int i;
114 unsigned int optsize = th->doff*4 - sizeof(struct tcphdr);
115
116 op = skb_header_pointer(skb, offset + sizeof(struct tcphdr),
117 optsize, _opt);
118 if (op == NULL) {
119 nf_log_buf_add(m, "OPT (TRUNCATED)");
120 return 1;
121 }
122
123
124 nf_log_buf_add(m, "OPT (");
125 for (i = 0; i < optsize; i++)
126 nf_log_buf_add(m, "%02X", op[i]);
127
128 nf_log_buf_add(m, ") ");
129 }
130
131 return 0;
132}
133EXPORT_SYMBOL_GPL(nf_log_dump_tcp_header);
134
135void nf_log_dump_sk_uid_gid(struct nf_log_buf *m, struct sock *sk)
136{
137 if (!sk || !sk_fullsock(sk))
138 return;
139
140 read_lock_bh(&sk->sk_callback_lock);
141 if (sk->sk_socket && sk->sk_socket->file) {
142 const struct cred *cred = sk->sk_socket->file->f_cred;
143 nf_log_buf_add(m, "UID=%u GID=%u ",
144 from_kuid_munged(&init_user_ns, cred->fsuid),
145 from_kgid_munged(&init_user_ns, cred->fsgid));
146 }
147 read_unlock_bh(&sk->sk_callback_lock);
148}
149EXPORT_SYMBOL_GPL(nf_log_dump_sk_uid_gid);
150
151void
152nf_log_dump_packet_common(struct nf_log_buf *m, u_int8_t pf,
153 unsigned int hooknum, const struct sk_buff *skb,
154 const struct net_device *in,
155 const struct net_device *out,
156 const struct nf_loginfo *loginfo, const char *prefix)
157{
158 nf_log_buf_add(m, KERN_SOH "%c%sIN=%s OUT=%s ",
159 '0' + loginfo->u.log.level, prefix,
160 in ? in->name : "",
161 out ? out->name : "");
162#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
163 if (skb->nf_bridge) {
164 const struct net_device *physindev;
165 const struct net_device *physoutdev;
166
167 physindev = nf_bridge_get_physindev(skb);
168 if (physindev && in != physindev)
169 nf_log_buf_add(m, "PHYSIN=%s ", physindev->name);
170 physoutdev = nf_bridge_get_physoutdev(skb);
171 if (physoutdev && out != physoutdev)
172 nf_log_buf_add(m, "PHYSOUT=%s ", physoutdev->name);
173 }
174#endif
175}
176EXPORT_SYMBOL_GPL(nf_log_dump_packet_common);
177
178static int __init nf_log_common_init(void)
179{
180 return 0;
181}
182
183static void __exit nf_log_common_exit(void) {}
184
185module_init(nf_log_common_init);
186module_exit(nf_log_common_exit);
187
188MODULE_LICENSE("GPL");
189
