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> |
3c73a036 | 11 | |
5a352dd0 HFS |
12 | static u32 __ipv6_select_ident(struct net *net, u32 hashrnd, |
13 | struct in6_addr *dst, struct in6_addr *src) | |
0508c07f VY |
14 | { |
15 | u32 hash, id; | |
16 | ||
17 | hash = __ipv6_addr_jhash(dst, hashrnd); | |
18 | hash = __ipv6_addr_jhash(src, hash); | |
5a352dd0 | 19 | hash ^= net_hash_mix(net); |
0508c07f VY |
20 | |
21 | /* Treat id of 0 as unset and if we get 0 back from ip_idents_reserve, | |
22 | * set the hight order instead thus minimizing possible future | |
23 | * collisions. | |
24 | */ | |
25 | id = ip_idents_reserve(hash, 1); | |
26 | if (unlikely(!id)) | |
27 | id = 1 << 31; | |
28 | ||
29 | return id; | |
30 | } | |
31 | ||
5188cd44 BH |
32 | /* This function exists only for tap drivers that must support broken |
33 | * clients requesting UFO without specifying an IPv6 fragment ID. | |
34 | * | |
35 | * This is similar to ipv6_select_ident() but we use an independent hash | |
36 | * seed to limit information leakage. | |
37 | * | |
38 | * The network header must be set before calling this. | |
39 | */ | |
5a352dd0 | 40 | void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb) |
5188cd44 BH |
41 | { |
42 | static u32 ip6_proxy_idents_hashrnd __read_mostly; | |
43 | struct in6_addr buf[2]; | |
44 | struct in6_addr *addrs; | |
0508c07f | 45 | u32 id; |
5188cd44 BH |
46 | |
47 | addrs = skb_header_pointer(skb, | |
48 | skb_network_offset(skb) + | |
49 | offsetof(struct ipv6hdr, saddr), | |
50 | sizeof(buf), buf); | |
51 | if (!addrs) | |
52 | return; | |
53 | ||
54 | net_get_random_once(&ip6_proxy_idents_hashrnd, | |
55 | sizeof(ip6_proxy_idents_hashrnd)); | |
56 | ||
5a352dd0 | 57 | id = __ipv6_select_ident(net, ip6_proxy_idents_hashrnd, |
0508c07f | 58 | &addrs[1], &addrs[0]); |
51f30770 | 59 | skb_shinfo(skb)->ip6_frag_id = htonl(id); |
5188cd44 BH |
60 | } |
61 | EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident); | |
62 | ||
5a352dd0 HFS |
63 | void ipv6_select_ident(struct net *net, struct frag_hdr *fhdr, |
64 | struct rt6_info *rt) | |
0508c07f VY |
65 | { |
66 | static u32 ip6_idents_hashrnd __read_mostly; | |
67 | u32 id; | |
68 | ||
69 | net_get_random_once(&ip6_idents_hashrnd, sizeof(ip6_idents_hashrnd)); | |
70 | ||
5a352dd0 | 71 | id = __ipv6_select_ident(net, ip6_idents_hashrnd, &rt->rt6i_dst.addr, |
0508c07f VY |
72 | &rt->rt6i_src.addr); |
73 | fhdr->identification = htonl(id); | |
74 | } | |
75 | EXPORT_SYMBOL(ipv6_select_ident); | |
76 | ||
3c73a036 VY |
77 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) |
78 | { | |
79 | u16 offset = sizeof(struct ipv6hdr); | |
80 | struct ipv6_opt_hdr *exthdr = | |
81 | (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); | |
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 | ||
87 | while (offset + 1 <= packet_len) { | |
88 | ||
89 | switch (**nexthdr) { | |
90 | ||
91 | case NEXTHDR_HOP: | |
92 | break; | |
93 | case NEXTHDR_ROUTING: | |
94 | found_rhdr = 1; | |
95 | break; | |
96 | case NEXTHDR_DEST: | |
97 | #if IS_ENABLED(CONFIG_IPV6_MIP6) | |
98 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) | |
99 | break; | |
100 | #endif | |
101 | if (found_rhdr) | |
102 | return offset; | |
103 | break; | |
67ba4152 | 104 | default: |
3c73a036 VY |
105 | return offset; |
106 | } | |
107 | ||
108 | offset += ipv6_optlen(exthdr); | |
109 | *nexthdr = &exthdr->nexthdr; | |
110 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + | |
111 | offset); | |
112 | } | |
113 | ||
114 | return offset; | |
115 | } | |
116 | EXPORT_SYMBOL(ip6_find_1stfragopt); | |
3ce9b35f CW |
117 | |
118 | #if IS_ENABLED(CONFIG_IPV6) | |
119 | int ip6_dst_hoplimit(struct dst_entry *dst) | |
120 | { | |
121 | int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); | |
122 | if (hoplimit == 0) { | |
123 | struct net_device *dev = dst->dev; | |
124 | struct inet6_dev *idev; | |
125 | ||
126 | rcu_read_lock(); | |
127 | idev = __in6_dev_get(dev); | |
128 | if (idev) | |
129 | hoplimit = idev->cnf.hop_limit; | |
130 | else | |
131 | hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; | |
132 | rcu_read_unlock(); | |
133 | } | |
134 | return hoplimit; | |
135 | } | |
136 | EXPORT_SYMBOL(ip6_dst_hoplimit); | |
137 | #endif | |
788787b5 CW |
138 | |
139 | int __ip6_local_out(struct sk_buff *skb) | |
140 | { | |
141 | int len; | |
142 | ||
143 | len = skb->len - sizeof(struct ipv6hdr); | |
144 | if (len > IPV6_MAXPLEN) | |
145 | len = 0; | |
146 | ipv6_hdr(skb)->payload_len = htons(len); | |
f6c20c59 | 147 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
788787b5 CW |
148 | |
149 | return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, | |
150 | skb_dst(skb)->dev, dst_output); | |
151 | } | |
152 | EXPORT_SYMBOL_GPL(__ip6_local_out); | |
153 | ||
154 | int ip6_local_out(struct sk_buff *skb) | |
155 | { | |
156 | int err; | |
157 | ||
158 | err = __ip6_local_out(skb); | |
159 | if (likely(err == 1)) | |
160 | err = dst_output(skb); | |
161 | ||
162 | return err; | |
163 | } | |
164 | EXPORT_SYMBOL_GPL(ip6_local_out); |