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 | |
8381eacf VY |
12 | static u32 __ipv6_select_ident(u32 hashrnd, struct in6_addr *dst, |
13 | 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); | |
19 | ||
20 | /* Treat id of 0 as unset and if we get 0 back from ip_idents_reserve, | |
21 | * set the hight order instead thus minimizing possible future | |
22 | * collisions. | |
23 | */ | |
24 | id = ip_idents_reserve(hash, 1); | |
25 | if (unlikely(!id)) | |
26 | id = 1 << 31; | |
27 | ||
28 | return id; | |
29 | } | |
30 | ||
5188cd44 BH |
31 | /* This function exists only for tap drivers that must support broken |
32 | * clients requesting UFO without specifying an IPv6 fragment ID. | |
33 | * | |
34 | * This is similar to ipv6_select_ident() but we use an independent hash | |
35 | * seed to limit information leakage. | |
36 | * | |
37 | * The network header must be set before calling this. | |
38 | */ | |
39 | void ipv6_proxy_select_ident(struct sk_buff *skb) | |
40 | { | |
41 | static u32 ip6_proxy_idents_hashrnd __read_mostly; | |
42 | struct in6_addr buf[2]; | |
43 | struct in6_addr *addrs; | |
0508c07f | 44 | u32 id; |
5188cd44 BH |
45 | |
46 | addrs = skb_header_pointer(skb, | |
47 | skb_network_offset(skb) + | |
48 | offsetof(struct ipv6hdr, saddr), | |
49 | sizeof(buf), buf); | |
50 | if (!addrs) | |
51 | return; | |
52 | ||
53 | net_get_random_once(&ip6_proxy_idents_hashrnd, | |
54 | sizeof(ip6_proxy_idents_hashrnd)); | |
55 | ||
0508c07f VY |
56 | id = __ipv6_select_ident(ip6_proxy_idents_hashrnd, |
57 | &addrs[1], &addrs[0]); | |
51f30770 | 58 | skb_shinfo(skb)->ip6_frag_id = htonl(id); |
5188cd44 BH |
59 | } |
60 | EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident); | |
61 | ||
0508c07f VY |
62 | void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt) |
63 | { | |
64 | static u32 ip6_idents_hashrnd __read_mostly; | |
65 | u32 id; | |
66 | ||
67 | net_get_random_once(&ip6_idents_hashrnd, sizeof(ip6_idents_hashrnd)); | |
68 | ||
69 | id = __ipv6_select_ident(ip6_idents_hashrnd, &rt->rt6i_dst.addr, | |
70 | &rt->rt6i_src.addr); | |
71 | fhdr->identification = htonl(id); | |
72 | } | |
73 | EXPORT_SYMBOL(ipv6_select_ident); | |
74 | ||
3c73a036 VY |
75 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) |
76 | { | |
77 | u16 offset = sizeof(struct ipv6hdr); | |
78 | struct ipv6_opt_hdr *exthdr = | |
79 | (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); | |
29a3cad5 SH |
80 | unsigned int packet_len = skb_tail_pointer(skb) - |
81 | skb_network_header(skb); | |
3c73a036 VY |
82 | int found_rhdr = 0; |
83 | *nexthdr = &ipv6_hdr(skb)->nexthdr; | |
84 | ||
85 | while (offset + 1 <= packet_len) { | |
86 | ||
87 | switch (**nexthdr) { | |
88 | ||
89 | case NEXTHDR_HOP: | |
90 | break; | |
91 | case NEXTHDR_ROUTING: | |
92 | found_rhdr = 1; | |
93 | break; | |
94 | case NEXTHDR_DEST: | |
95 | #if IS_ENABLED(CONFIG_IPV6_MIP6) | |
96 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) | |
97 | break; | |
98 | #endif | |
99 | if (found_rhdr) | |
100 | return offset; | |
101 | break; | |
67ba4152 | 102 | default: |
3c73a036 VY |
103 | return offset; |
104 | } | |
105 | ||
106 | offset += ipv6_optlen(exthdr); | |
107 | *nexthdr = &exthdr->nexthdr; | |
108 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + | |
109 | offset); | |
110 | } | |
111 | ||
112 | return offset; | |
113 | } | |
114 | EXPORT_SYMBOL(ip6_find_1stfragopt); | |
3ce9b35f CW |
115 | |
116 | #if IS_ENABLED(CONFIG_IPV6) | |
117 | int ip6_dst_hoplimit(struct dst_entry *dst) | |
118 | { | |
119 | int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); | |
120 | if (hoplimit == 0) { | |
121 | struct net_device *dev = dst->dev; | |
122 | struct inet6_dev *idev; | |
123 | ||
124 | rcu_read_lock(); | |
125 | idev = __in6_dev_get(dev); | |
126 | if (idev) | |
127 | hoplimit = idev->cnf.hop_limit; | |
128 | else | |
129 | hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; | |
130 | rcu_read_unlock(); | |
131 | } | |
132 | return hoplimit; | |
133 | } | |
134 | EXPORT_SYMBOL(ip6_dst_hoplimit); | |
135 | #endif | |
788787b5 CW |
136 | |
137 | int __ip6_local_out(struct sk_buff *skb) | |
138 | { | |
139 | int len; | |
140 | ||
141 | len = skb->len - sizeof(struct ipv6hdr); | |
142 | if (len > IPV6_MAXPLEN) | |
143 | len = 0; | |
144 | ipv6_hdr(skb)->payload_len = htons(len); | |
f6c20c59 | 145 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
788787b5 CW |
146 | |
147 | return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, | |
148 | skb_dst(skb)->dev, dst_output); | |
149 | } | |
150 | EXPORT_SYMBOL_GPL(__ip6_local_out); | |
151 | ||
152 | int ip6_local_out(struct sk_buff *skb) | |
153 | { | |
154 | int err; | |
155 | ||
156 | err = __ip6_local_out(skb); | |
157 | if (likely(err == 1)) | |
158 | err = dst_output(skb); | |
159 | ||
160 | return err; | |
161 | } | |
162 | EXPORT_SYMBOL_GPL(ip6_local_out); |