Thomas Gleixner | 457c899 | 2019-05-19 13:08:55 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 2 | /* |
| 3 | * IPv6 library code, needed by static components when full IPv6 support is |
| 4 | * not configured or static. These functions are needed by GSO/GRO implementation. |
| 5 | */ |
| 6 | #include <linux/export.h> |
Ben Hutchings | 5188cd4 | 2014-10-30 18:27:17 +0000 | [diff] [blame] | 7 | #include <net/ip.h> |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 8 | #include <net/ipv6.h> |
| 9 | #include <net/ip6_fib.h> |
Cong Wang | 3ce9b35 | 2013-08-31 13:44:28 +0800 | [diff] [blame] | 10 | #include <net/addrconf.h> |
Hannes Frederic Sowa | 6dfac5c | 2014-03-30 18:28:03 +0200 | [diff] [blame] | 11 | #include <net/secure_seq.h> |
Pablo Neira Ayuso | a263653 | 2015-06-17 10:28:27 -0500 | [diff] [blame] | 12 | #include <linux/netfilter.h> |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 13 | |
Eric Dumazet | df45370 | 2019-03-27 12:40:33 -0700 | [diff] [blame] | 14 | static u32 __ipv6_select_ident(struct net *net, |
Martin KaFai Lau | fd0273d | 2015-05-22 20:55:57 -0700 | [diff] [blame] | 15 | const struct in6_addr *dst, |
| 16 | const struct in6_addr *src) |
Vlad Yasevich | 0508c07 | 2015-02-03 16:36:15 -0500 | [diff] [blame] | 17 | { |
Jason A. Donenfeld | d247aab | 2022-10-09 20:44:02 -0600 | [diff] [blame] | 18 | return get_random_u32_above(0); |
Vlad Yasevich | 0508c07 | 2015-02-03 16:36:15 -0500 | [diff] [blame] | 19 | } |
| 20 | |
Willem de Bruijn | 0c19f846 | 2017-11-21 10:22:25 -0500 | [diff] [blame] | 21 | /* This function exists only for tap drivers that must support broken |
| 22 | * clients requesting UFO without specifying an IPv6 fragment ID. |
| 23 | * |
| 24 | * This is similar to ipv6_select_ident() but we use an independent hash |
| 25 | * seed to limit information leakage. |
| 26 | * |
| 27 | * The network header must be set before calling this. |
| 28 | */ |
| 29 | __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb) |
| 30 | { |
Willem de Bruijn | 0c19f846 | 2017-11-21 10:22:25 -0500 | [diff] [blame] | 31 | struct in6_addr buf[2]; |
| 32 | struct in6_addr *addrs; |
| 33 | u32 id; |
| 34 | |
| 35 | addrs = skb_header_pointer(skb, |
| 36 | skb_network_offset(skb) + |
| 37 | offsetof(struct ipv6hdr, saddr), |
| 38 | sizeof(buf), buf); |
| 39 | if (!addrs) |
| 40 | return 0; |
| 41 | |
Eric Dumazet | df45370 | 2019-03-27 12:40:33 -0700 | [diff] [blame] | 42 | id = __ipv6_select_ident(net, &addrs[1], &addrs[0]); |
Willem de Bruijn | 0c19f846 | 2017-11-21 10:22:25 -0500 | [diff] [blame] | 43 | return htonl(id); |
| 44 | } |
| 45 | EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident); |
| 46 | |
Eric Dumazet | 7f15986 | 2015-05-25 16:02:21 -0700 | [diff] [blame] | 47 | __be32 ipv6_select_ident(struct net *net, |
| 48 | const struct in6_addr *daddr, |
| 49 | const struct in6_addr *saddr) |
Vlad Yasevich | 0508c07 | 2015-02-03 16:36:15 -0500 | [diff] [blame] | 50 | { |
Vlad Yasevich | 0508c07 | 2015-02-03 16:36:15 -0500 | [diff] [blame] | 51 | u32 id; |
| 52 | |
Eric Dumazet | df45370 | 2019-03-27 12:40:33 -0700 | [diff] [blame] | 53 | id = __ipv6_select_ident(net, daddr, saddr); |
Martin KaFai Lau | 286c234 | 2015-05-22 20:55:56 -0700 | [diff] [blame] | 54 | return htonl(id); |
Vlad Yasevich | 0508c07 | 2015-02-03 16:36:15 -0500 | [diff] [blame] | 55 | } |
| 56 | EXPORT_SYMBOL(ipv6_select_ident); |
| 57 | |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 58 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) |
| 59 | { |
Sabrina Dubroca | 6399f1f | 2017-07-19 22:28:55 +0200 | [diff] [blame] | 60 | unsigned int offset = sizeof(struct ipv6hdr); |
Simon Horman | 29a3cad | 2013-05-28 20:34:26 +0000 | [diff] [blame] | 61 | unsigned int packet_len = skb_tail_pointer(skb) - |
| 62 | skb_network_header(skb); |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 63 | int found_rhdr = 0; |
| 64 | *nexthdr = &ipv6_hdr(skb)->nexthdr; |
| 65 | |
Craig Gallek | 2423496 | 2017-05-16 14:36:23 -0400 | [diff] [blame] | 66 | while (offset <= packet_len) { |
| 67 | struct ipv6_opt_hdr *exthdr; |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 68 | |
| 69 | switch (**nexthdr) { |
| 70 | |
| 71 | case NEXTHDR_HOP: |
| 72 | break; |
| 73 | case NEXTHDR_ROUTING: |
| 74 | found_rhdr = 1; |
| 75 | break; |
| 76 | case NEXTHDR_DEST: |
| 77 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
| 78 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) |
| 79 | break; |
| 80 | #endif |
| 81 | if (found_rhdr) |
| 82 | return offset; |
| 83 | break; |
Ian Morris | 67ba415 | 2014-08-24 21:53:10 +0100 | [diff] [blame] | 84 | default: |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 85 | return offset; |
| 86 | } |
| 87 | |
Craig Gallek | 2423496 | 2017-05-16 14:36:23 -0400 | [diff] [blame] | 88 | if (offset + sizeof(struct ipv6_opt_hdr) > packet_len) |
| 89 | return -EINVAL; |
| 90 | |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 91 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + |
| 92 | offset); |
Stefano Brivio | 3de33e1 | 2017-08-18 14:40:53 +0200 | [diff] [blame] | 93 | offset += ipv6_optlen(exthdr); |
| 94 | if (offset > IPV6_MAXPLEN) |
Sabrina Dubroca | 6399f1f | 2017-07-19 22:28:55 +0200 | [diff] [blame] | 95 | return -EINVAL; |
Craig Gallek | 2423496 | 2017-05-16 14:36:23 -0400 | [diff] [blame] | 96 | *nexthdr = &exthdr->nexthdr; |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 97 | } |
| 98 | |
Craig Gallek | 2423496 | 2017-05-16 14:36:23 -0400 | [diff] [blame] | 99 | return -EINVAL; |
Vlad Yasevich | 3c73a03 | 2012-11-15 08:49:20 +0000 | [diff] [blame] | 100 | } |
| 101 | EXPORT_SYMBOL(ip6_find_1stfragopt); |
Cong Wang | 3ce9b35 | 2013-08-31 13:44:28 +0800 | [diff] [blame] | 102 | |
| 103 | #if IS_ENABLED(CONFIG_IPV6) |
| 104 | int ip6_dst_hoplimit(struct dst_entry *dst) |
| 105 | { |
| 106 | int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); |
| 107 | if (hoplimit == 0) { |
| 108 | struct net_device *dev = dst->dev; |
| 109 | struct inet6_dev *idev; |
| 110 | |
| 111 | rcu_read_lock(); |
| 112 | idev = __in6_dev_get(dev); |
| 113 | if (idev) |
| 114 | hoplimit = idev->cnf.hop_limit; |
| 115 | else |
| 116 | hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; |
| 117 | rcu_read_unlock(); |
| 118 | } |
| 119 | return hoplimit; |
| 120 | } |
| 121 | EXPORT_SYMBOL(ip6_dst_hoplimit); |
| 122 | #endif |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 123 | |
Eric W. Biederman | cf91a99 | 2015-10-07 16:48:45 -0500 | [diff] [blame] | 124 | int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 125 | { |
| 126 | int len; |
| 127 | |
| 128 | len = skb->len - sizeof(struct ipv6hdr); |
| 129 | if (len > IPV6_MAXPLEN) |
| 130 | len = 0; |
| 131 | ipv6_hdr(skb)->payload_len = htons(len); |
huizhang | f6c20c5 | 2014-06-09 12:37:25 +0800 | [diff] [blame] | 132 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 133 | |
David Ahern | a8e3e1a | 2016-09-10 12:09:53 -0700 | [diff] [blame] | 134 | /* if egress device is enslaved to an L3 master device pass the |
| 135 | * skb to its handler for processing |
| 136 | */ |
| 137 | skb = l3mdev_ip6_out(sk, skb); |
| 138 | if (unlikely(!skb)) |
| 139 | return 0; |
| 140 | |
Eli Cooper | b4e479a9 | 2016-12-01 10:05:11 +0800 | [diff] [blame] | 141 | skb->protocol = htons(ETH_P_IPV6); |
| 142 | |
Eric W. Biederman | 29a26a5 | 2015-09-15 20:04:16 -0500 | [diff] [blame] | 143 | return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, |
| 144 | net, sk, skb, NULL, skb_dst(skb)->dev, |
Eric W. Biederman | 13206b6 | 2015-10-07 16:48:35 -0500 | [diff] [blame] | 145 | dst_output); |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 146 | } |
| 147 | EXPORT_SYMBOL_GPL(__ip6_local_out); |
| 148 | |
Eric W. Biederman | 33224b1 | 2015-10-07 16:48:46 -0500 | [diff] [blame] | 149 | int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 150 | { |
| 151 | int err; |
| 152 | |
Eric W. Biederman | cf91a99 | 2015-10-07 16:48:45 -0500 | [diff] [blame] | 153 | err = __ip6_local_out(net, sk, skb); |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 154 | if (likely(err == 1)) |
Eric W. Biederman | 13206b6 | 2015-10-07 16:48:35 -0500 | [diff] [blame] | 155 | err = dst_output(net, sk, skb); |
Cong Wang | 788787b | 2013-08-31 13:44:29 +0800 | [diff] [blame] | 156 | |
| 157 | return err; |
| 158 | } |
| 159 | EXPORT_SYMBOL_GPL(ip6_local_out); |