hc
2024-12-19 9370bb92b2d16684ee45cf24e879c93c509162da
kernel/net/ipv6/xfrm6_output.c
....@@ -1,12 +1,8 @@
1
+// SPDX-License-Identifier: GPL-2.0-or-later
12 /*
23 * xfrm6_output.c - Common IPsec encapsulation code for IPv6.
34 * Copyright (C) 2002 USAGI/WIDE Project
45 * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
5
- *
6
- * This program is free software; you can redistribute it and/or
7
- * modify it under the terms of the GNU General Public License
8
- * as published by the Free Software Foundation; either version
9
- * 2 of the License, or (at your option) any later version.
106 */
117
128 #include <linux/if_ether.h>
....@@ -27,24 +23,7 @@
2723 }
2824 EXPORT_SYMBOL(xfrm6_find_1stfragopt);
2925
30
-static int xfrm6_local_dontfrag(struct sk_buff *skb)
31
-{
32
- int proto;
33
- struct sock *sk = skb->sk;
34
-
35
- if (sk) {
36
- if (sk->sk_family != AF_INET6)
37
- return 0;
38
-
39
- proto = sk->sk_protocol;
40
- if (proto == IPPROTO_UDP || proto == IPPROTO_RAW)
41
- return inet6_sk(sk)->dontfrag;
42
- }
43
-
44
- return 0;
45
-}
46
-
47
-static void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
26
+void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
4827 {
4928 struct flowi6 fl6;
5029 struct sock *sk = skb->sk;
....@@ -68,78 +47,22 @@
6847 ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
6948 }
7049
71
-static int xfrm6_tunnel_check_size(struct sk_buff *skb)
50
+static int __xfrm6_output_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
7251 {
73
- int mtu, ret = 0;
74
- struct dst_entry *dst = skb_dst(skb);
75
-
76
- if (skb->ignore_df)
77
- goto out;
78
-
79
- mtu = dst_mtu(dst);
80
- if (mtu < IPV6_MIN_MTU)
81
- mtu = IPV6_MIN_MTU;
82
-
83
- if ((!skb_is_gso(skb) && skb->len > mtu) ||
84
- (skb_is_gso(skb) &&
85
- !skb_gso_validate_network_len(skb, ip6_skb_dst_mtu(skb)))) {
86
- skb->dev = dst->dev;
87
- skb->protocol = htons(ETH_P_IPV6);
88
-
89
- if (xfrm6_local_dontfrag(skb))
90
- xfrm6_local_rxpmtu(skb, mtu);
91
- else if (skb->sk)
92
- xfrm_local_error(skb, mtu);
93
- else
94
- icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
95
- ret = -EMSGSIZE;
96
- }
97
-out:
98
- return ret;
99
-}
100
-
101
-int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
102
-{
103
- int err;
104
-
105
- err = xfrm6_tunnel_check_size(skb);
106
- if (err)
107
- return err;
108
-
109
- XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
110
-
111
- return xfrm6_extract_header(skb);
112
-}
113
-
114
-int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
115
-{
116
- int err;
117
-
118
- err = xfrm_inner_extract_output(x, skb);
119
- if (err)
120
- return err;
121
-
122
- skb->ignore_df = 1;
123
- skb->protocol = htons(ETH_P_IPV6);
124
-
125
- return x->outer_mode->output2(x, skb);
126
-}
127
-EXPORT_SYMBOL(xfrm6_prepare_output);
128
-
129
-int xfrm6_output_finish(struct sock *sk, struct sk_buff *skb)
130
-{
131
- memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
132
-
133
- IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
134
-
13552 return xfrm_output(sk, skb);
13653 }
13754
138
-static int __xfrm6_output_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
55
+static int xfrm6_noneed_fragment(struct sk_buff *skb)
13956 {
140
- struct xfrm_state *x = skb_dst(skb)->xfrm;
57
+ struct frag_hdr *fh;
58
+ u8 prevhdr = ipv6_hdr(skb)->nexthdr;
14159
142
- return x->outer_mode->afinfo->output_finish(sk, skb);
60
+ if (prevhdr != NEXTHDR_FRAGMENT)
61
+ return 0;
62
+ fh = (struct frag_hdr *)(skb->data + sizeof(struct ipv6hdr));
63
+ if (fh->nexthdr == NEXTHDR_ESP || fh->nexthdr == NEXTHDR_AUTH)
64
+ return 1;
65
+ return 0;
14366 }
14467
14568 static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
....@@ -166,10 +89,13 @@
16689
16790 toobig = skb->len > mtu && !skb_is_gso(skb);
16891
169
- if (toobig && xfrm6_local_dontfrag(skb)) {
92
+ if (toobig && xfrm6_local_dontfrag(skb->sk)) {
17093 xfrm6_local_rxpmtu(skb, mtu);
17194 kfree_skb(skb);
17295 return -EMSGSIZE;
96
+ } else if (toobig && xfrm6_noneed_fragment(skb)) {
97
+ skb->ignore_df = 1;
98
+ goto skip_frag;
17399 } else if (!skb->ignore_df && toobig && skb->sk) {
174100 xfrm_local_error(skb, mtu);
175101 kfree_skb(skb);
....@@ -181,13 +107,13 @@
181107 __xfrm6_output_finish);
182108
183109 skip_frag:
184
- return x->outer_mode->afinfo->output_finish(sk, skb);
110
+ return xfrm_output(sk, skb);
185111 }
186112
187113 int xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
188114 {
189115 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
190
- net, sk, skb, NULL, skb_dst(skb)->dev,
116
+ net, sk, skb, skb->dev, skb_dst(skb)->dev,
191117 __xfrm6_output,
192118 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
193119 }