diff options
Diffstat (limited to 'net/ipv6/output_core.c')
| -rw-r--r-- | net/ipv6/output_core.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c new file mode 100644 index 000000000..2685c3f15 --- /dev/null +++ b/net/ipv6/output_core.c @@ -0,0 +1,165 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * IPv6 library code, needed by static components when full IPv6 support is + * not configured or static. These functions are needed by GSO/GRO implementation. + */ +#include <linux/export.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <net/ip6_fib.h> +#include <net/addrconf.h> +#include <net/secure_seq.h> +#include <linux/netfilter.h> + +static u32 __ipv6_select_ident(struct net *net, + const struct in6_addr *dst, + const struct in6_addr *src) +{ + u32 id; + + do { + id = get_random_u32(); + } while (!id); + + return id; +} + +/* This function exists only for tap drivers that must support broken + * clients requesting UFO without specifying an IPv6 fragment ID. + * + * This is similar to ipv6_select_ident() but we use an independent hash + * seed to limit information leakage. + * + * The network header must be set before calling this. + */ +__be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb) +{ + struct in6_addr buf[2]; + struct in6_addr *addrs; + u32 id; + + addrs = skb_header_pointer(skb, + skb_network_offset(skb) + + offsetof(struct ipv6hdr, saddr), + sizeof(buf), buf); + if (!addrs) + return 0; + + id = __ipv6_select_ident(net, &addrs[1], &addrs[0]); + return htonl(id); +} +EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident); + +__be32 ipv6_select_ident(struct net *net, + const struct in6_addr *daddr, + const struct in6_addr *saddr) +{ + u32 id; + + id = __ipv6_select_ident(net, daddr, saddr); + return htonl(id); +} +EXPORT_SYMBOL(ipv6_select_ident); + +int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) +{ + unsigned int offset = sizeof(struct ipv6hdr); + unsigned int packet_len = skb_tail_pointer(skb) - + skb_network_header(skb); + int found_rhdr = 0; + *nexthdr = &ipv6_hdr(skb)->nexthdr; + + while (offset <= packet_len) { + struct ipv6_opt_hdr *exthdr; + + switch (**nexthdr) { + + case NEXTHDR_HOP: + break; + case NEXTHDR_ROUTING: + found_rhdr = 1; + break; + case NEXTHDR_DEST: +#if IS_ENABLED(CONFIG_IPV6_MIP6) + if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) + break; +#endif + if (found_rhdr) + return offset; + break; + default: + return offset; + } + + if (offset + sizeof(struct ipv6_opt_hdr) > packet_len) + return -EINVAL; + + exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + + offset); + offset += ipv6_optlen(exthdr); + if (offset > IPV6_MAXPLEN) + return -EINVAL; + *nexthdr = &exthdr->nexthdr; + } + + return -EINVAL; +} +EXPORT_SYMBOL(ip6_find_1stfragopt); + +#if IS_ENABLED(CONFIG_IPV6) +int ip6_dst_hoplimit(struct dst_entry *dst) +{ + int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); + if (hoplimit == 0) { + struct net_device *dev = dst->dev; + struct inet6_dev *idev; + + rcu_read_lock(); + idev = __in6_dev_get(dev); + if (idev) + hoplimit = idev->cnf.hop_limit; + else + hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; + rcu_read_unlock(); + } + return hoplimit; +} +EXPORT_SYMBOL(ip6_dst_hoplimit); +#endif + +int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) +{ + int len; + + len = skb->len - sizeof(struct ipv6hdr); + if (len > IPV6_MAXPLEN) + len = 0; + ipv6_hdr(skb)->payload_len = htons(len); + IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); + + /* if egress device is enslaved to an L3 master device pass the + * skb to its handler for processing + */ + skb = l3mdev_ip6_out(sk, skb); + if (unlikely(!skb)) + return 0; + + skb->protocol = htons(ETH_P_IPV6); + + return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, + net, sk, skb, NULL, skb_dst(skb)->dev, + dst_output); +} +EXPORT_SYMBOL_GPL(__ip6_local_out); + +int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) +{ + int err; + + err = __ip6_local_out(net, sk, skb); + if (likely(err == 1)) + err = dst_output(net, sk, skb); + + return err; +} +EXPORT_SYMBOL_GPL(ip6_local_out); |