Commit | Line | Data |
---|---|---|
3c73a036 VY |
1 | /* |
2 | * IPv6 library code, needed by static components when full IPv6 support is | |
3 | * not configured or static. These functions are needed by GSO/GRO implementation. | |
4 | */ | |
5 | #include <linux/export.h> | |
5188cd44 | 6 | #include <net/ip.h> |
3c73a036 VY |
7 | #include <net/ipv6.h> |
8 | #include <net/ip6_fib.h> | |
3ce9b35f | 9 | #include <net/addrconf.h> |
6dfac5c3 | 10 | #include <net/secure_seq.h> |
a263653e | 11 | #include <linux/netfilter.h> |
3c73a036 | 12 | |
5a352dd0 | 13 | static u32 __ipv6_select_ident(struct net *net, u32 hashrnd, |
fd0273d7 MKL |
14 | const struct in6_addr *dst, |
15 | const struct in6_addr *src) | |
0508c07f VY |
16 | { |
17 | u32 hash, id; | |
18 | ||
19 | hash = __ipv6_addr_jhash(dst, hashrnd); | |
20 | hash = __ipv6_addr_jhash(src, hash); | |
5a352dd0 | 21 | hash ^= net_hash_mix(net); |
0508c07f VY |
22 | |
23 | /* Treat id of 0 as unset and if we get 0 back from ip_idents_reserve, | |
24 | * set the hight order instead thus minimizing possible future | |
25 | * collisions. | |
26 | */ | |
27 | id = ip_idents_reserve(hash, 1); | |
28 | if (unlikely(!id)) | |
29 | id = 1 << 31; | |
30 | ||
31 | return id; | |
32 | } | |
33 | ||
5188cd44 BH |
34 | /* This function exists only for tap drivers that must support broken |
35 | * clients requesting UFO without specifying an IPv6 fragment ID. | |
36 | * | |
37 | * This is similar to ipv6_select_ident() but we use an independent hash | |
38 | * seed to limit information leakage. | |
39 | * | |
40 | * The network header must be set before calling this. | |
41 | */ | |
5a352dd0 | 42 | void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb) |
5188cd44 BH |
43 | { |
44 | static u32 ip6_proxy_idents_hashrnd __read_mostly; | |
45 | struct in6_addr buf[2]; | |
46 | struct in6_addr *addrs; | |
0508c07f | 47 | u32 id; |
5188cd44 BH |
48 | |
49 | addrs = skb_header_pointer(skb, | |
50 | skb_network_offset(skb) + | |
51 | offsetof(struct ipv6hdr, saddr), | |
52 | sizeof(buf), buf); | |
53 | if (!addrs) | |
54 | return; | |
55 | ||
56 | net_get_random_once(&ip6_proxy_idents_hashrnd, | |
57 | sizeof(ip6_proxy_idents_hashrnd)); | |
58 | ||
5a352dd0 | 59 | id = __ipv6_select_ident(net, ip6_proxy_idents_hashrnd, |
0508c07f | 60 | &addrs[1], &addrs[0]); |
51f30770 | 61 | skb_shinfo(skb)->ip6_frag_id = htonl(id); |
5188cd44 BH |
62 | } |
63 | EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident); | |
64 | ||
7f159867 ED |
65 | __be32 ipv6_select_ident(struct net *net, |
66 | const struct in6_addr *daddr, | |
67 | const struct in6_addr *saddr) | |
0508c07f VY |
68 | { |
69 | static u32 ip6_idents_hashrnd __read_mostly; | |
70 | u32 id; | |
71 | ||
72 | net_get_random_once(&ip6_idents_hashrnd, sizeof(ip6_idents_hashrnd)); | |
73 | ||
fd0273d7 | 74 | id = __ipv6_select_ident(net, ip6_idents_hashrnd, daddr, saddr); |
286c2349 | 75 | return htonl(id); |
0508c07f VY |
76 | } |
77 | EXPORT_SYMBOL(ipv6_select_ident); | |
78 | ||
3c73a036 VY |
79 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) |
80 | { | |
81 | u16 offset = sizeof(struct ipv6hdr); | |
29a3cad5 SH |
82 | unsigned int packet_len = skb_tail_pointer(skb) - |
83 | skb_network_header(skb); | |
3c73a036 VY |
84 | int found_rhdr = 0; |
85 | *nexthdr = &ipv6_hdr(skb)->nexthdr; | |
86 | ||
2423496a CG |
87 | while (offset <= packet_len) { |
88 | struct ipv6_opt_hdr *exthdr; | |
3c73a036 VY |
89 | |
90 | switch (**nexthdr) { | |
91 | ||
92 | case NEXTHDR_HOP: | |
93 | break; | |
94 | case NEXTHDR_ROUTING: | |
95 | found_rhdr = 1; | |
96 | break; | |
97 | case NEXTHDR_DEST: | |
98 | #if IS_ENABLED(CONFIG_IPV6_MIP6) | |
99 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) | |
100 | break; | |
101 | #endif | |
102 | if (found_rhdr) | |
103 | return offset; | |
104 | break; | |
67ba4152 | 105 | default: |
3c73a036 VY |
106 | return offset; |
107 | } | |
108 | ||
2423496a CG |
109 | if (offset + sizeof(struct ipv6_opt_hdr) > packet_len) |
110 | return -EINVAL; | |
111 | ||
3c73a036 VY |
112 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + |
113 | offset); | |
2423496a CG |
114 | offset += ipv6_optlen(exthdr); |
115 | *nexthdr = &exthdr->nexthdr; | |
3c73a036 VY |
116 | } |
117 | ||
2423496a | 118 | return -EINVAL; |
3c73a036 VY |
119 | } |
120 | EXPORT_SYMBOL(ip6_find_1stfragopt); | |
3ce9b35f CW |
121 | |
122 | #if IS_ENABLED(CONFIG_IPV6) | |
123 | int ip6_dst_hoplimit(struct dst_entry *dst) | |
124 | { | |
125 | int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); | |
126 | if (hoplimit == 0) { | |
127 | struct net_device *dev = dst->dev; | |
128 | struct inet6_dev *idev; | |
129 | ||
130 | rcu_read_lock(); | |
131 | idev = __in6_dev_get(dev); | |
132 | if (idev) | |
133 | hoplimit = idev->cnf.hop_limit; | |
134 | else | |
135 | hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; | |
136 | rcu_read_unlock(); | |
137 | } | |
138 | return hoplimit; | |
139 | } | |
140 | EXPORT_SYMBOL(ip6_dst_hoplimit); | |
141 | #endif | |
788787b5 | 142 | |
cf91a99d | 143 | int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) |
788787b5 CW |
144 | { |
145 | int len; | |
146 | ||
147 | len = skb->len - sizeof(struct ipv6hdr); | |
148 | if (len > IPV6_MAXPLEN) | |
149 | len = 0; | |
150 | ipv6_hdr(skb)->payload_len = htons(len); | |
f6c20c59 | 151 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
788787b5 | 152 | |
a8e3e1a9 DA |
153 | /* if egress device is enslaved to an L3 master device pass the |
154 | * skb to its handler for processing | |
155 | */ | |
156 | skb = l3mdev_ip6_out(sk, skb); | |
157 | if (unlikely(!skb)) | |
158 | return 0; | |
159 | ||
b4e479a9 EC |
160 | skb->protocol = htons(ETH_P_IPV6); |
161 | ||
29a26a56 EB |
162 | return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, |
163 | net, sk, skb, NULL, skb_dst(skb)->dev, | |
13206b6b | 164 | dst_output); |
788787b5 CW |
165 | } |
166 | EXPORT_SYMBOL_GPL(__ip6_local_out); | |
167 | ||
33224b16 | 168 | int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) |
788787b5 CW |
169 | { |
170 | int err; | |
171 | ||
cf91a99d | 172 | err = __ip6_local_out(net, sk, skb); |
788787b5 | 173 | if (likely(err == 1)) |
13206b6b | 174 | err = dst_output(net, sk, skb); |
788787b5 CW |
175 | |
176 | return err; | |
177 | } | |
178 | EXPORT_SYMBOL_GPL(ip6_local_out); |