linux/net/ipv6/output_core.c
Eric Dumazet 63081dec9e ipv6: move ip6_dst_hoplimit() to net/ipv6/ip6_output.c
Move ip6_dst_hoplimit() to net/ipv6/ip6_output.c so that compiler
can (auto)inline it from ip6_xmit().

$ scripts/bloat-o-meter -t vmlinux.0 vmlinux.1
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-11 (-11)
Function                                     old     new   delta
ip6_xmit                                    1684    1673     -11
Total: Before=29655407, After=29655396, chg -0.00%

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260331174722.4128061-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-01 18:50:35 -07:00

134 lines
3.2 KiB
C

// 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)
{
return get_random_u32_above(0);
}
/* 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);
int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb)
{
ipv6_set_payload_len(ipv6_hdr(skb), skb->len - sizeof(struct ipv6hdr));
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_dev(skb),
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);