From c53ac41e3720926301c623d6682bb87ce992a3b3 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 16 Apr 2019 16:44:39 +0200 Subject: xfrm: remove decode_session indirection from afinfo_policy No external dependencies, might as well handle this directly. xfrm_afinfo_policy is now 40 bytes on x86_64. Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_policy.c | 231 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 222 insertions(+), 9 deletions(-) (limited to 'net/xfrm') diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 5359c312f016..03b6bf85d70b 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -27,10 +27,14 @@ #include #include #include +#include #include #include #include #include +#if IS_ENABLED(CONFIG_IPV6_MIP6) +#include +#endif #ifdef CONFIG_XFRM_STATISTICS #include #endif @@ -3256,20 +3260,229 @@ xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int star return start; } +static void +decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) +{ + const struct iphdr *iph = ip_hdr(skb); + u8 *xprth = skb_network_header(skb) + iph->ihl * 4; + struct flowi4 *fl4 = &fl->u.ip4; + int oif = 0; + + if (skb_dst(skb)) + oif = skb_dst(skb)->dev->ifindex; + + memset(fl4, 0, sizeof(struct flowi4)); + fl4->flowi4_mark = skb->mark; + fl4->flowi4_oif = reverse ? skb->skb_iif : oif; + + if (!ip_is_fragment(iph)) { + switch (iph->protocol) { + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + case IPPROTO_TCP: + case IPPROTO_SCTP: + case IPPROTO_DCCP: + if (xprth + 4 < skb->data || + pskb_may_pull(skb, xprth + 4 - skb->data)) { + __be16 *ports; + + xprth = skb_network_header(skb) + iph->ihl * 4; + ports = (__be16 *)xprth; + + fl4->fl4_sport = ports[!!reverse]; + fl4->fl4_dport = ports[!reverse]; + } + break; + case IPPROTO_ICMP: + if (xprth + 2 < skb->data || + pskb_may_pull(skb, xprth + 2 - skb->data)) { + u8 *icmp; + + xprth = skb_network_header(skb) + iph->ihl * 4; + icmp = xprth; + + fl4->fl4_icmp_type = icmp[0]; + fl4->fl4_icmp_code = icmp[1]; + } + break; + case IPPROTO_ESP: + if (xprth + 4 < skb->data || + pskb_may_pull(skb, xprth + 4 - skb->data)) { + __be32 *ehdr; + + xprth = skb_network_header(skb) + iph->ihl * 4; + ehdr = (__be32 *)xprth; + + fl4->fl4_ipsec_spi = ehdr[0]; + } + break; + case IPPROTO_AH: + if (xprth + 8 < skb->data || + pskb_may_pull(skb, xprth + 8 - skb->data)) { + __be32 *ah_hdr; + + xprth = skb_network_header(skb) + iph->ihl * 4; + ah_hdr = (__be32 *)xprth; + + fl4->fl4_ipsec_spi = ah_hdr[1]; + } + break; + case IPPROTO_COMP: + if (xprth + 4 < skb->data || + pskb_may_pull(skb, xprth + 4 - skb->data)) { + __be16 *ipcomp_hdr; + + xprth = skb_network_header(skb) + iph->ihl * 4; + ipcomp_hdr = (__be16 *)xprth; + + fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); + } + break; + case IPPROTO_GRE: + if (xprth + 12 < skb->data || + pskb_may_pull(skb, xprth + 12 - skb->data)) { + __be16 *greflags; + __be32 *gre_hdr; + + xprth = skb_network_header(skb) + iph->ihl * 4; + greflags = (__be16 *)xprth; + gre_hdr = (__be32 *)xprth; + + if (greflags[0] & GRE_KEY) { + if (greflags[0] & GRE_CSUM) + gre_hdr++; + fl4->fl4_gre_key = gre_hdr[1]; + } + } + break; + default: + fl4->fl4_ipsec_spi = 0; + break; + } + } + fl4->flowi4_proto = iph->protocol; + fl4->daddr = reverse ? iph->saddr : iph->daddr; + fl4->saddr = reverse ? iph->daddr : iph->saddr; + fl4->flowi4_tos = iph->tos; +} + +#if IS_ENABLED(CONFIG_IPV6) +static void +decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) +{ + struct flowi6 *fl6 = &fl->u.ip6; + int onlyproto = 0; + const struct ipv6hdr *hdr = ipv6_hdr(skb); + u32 offset = sizeof(*hdr); + struct ipv6_opt_hdr *exthdr; + const unsigned char *nh = skb_network_header(skb); + u16 nhoff = IP6CB(skb)->nhoff; + int oif = 0; + u8 nexthdr; + + if (!nhoff) + nhoff = offsetof(struct ipv6hdr, nexthdr); + + nexthdr = nh[nhoff]; + + if (skb_dst(skb)) + oif = skb_dst(skb)->dev->ifindex; + + memset(fl6, 0, sizeof(struct flowi6)); + fl6->flowi6_mark = skb->mark; + fl6->flowi6_oif = reverse ? skb->skb_iif : oif; + + fl6->daddr = reverse ? hdr->saddr : hdr->daddr; + fl6->saddr = reverse ? hdr->daddr : hdr->saddr; + + while (nh + offset + sizeof(*exthdr) < skb->data || + pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { + nh = skb_network_header(skb); + exthdr = (struct ipv6_opt_hdr *)(nh + offset); + + switch (nexthdr) { + case NEXTHDR_FRAGMENT: + onlyproto = 1; + /* fall through */ + case NEXTHDR_ROUTING: + case NEXTHDR_HOP: + case NEXTHDR_DEST: + offset += ipv6_optlen(exthdr); + nexthdr = exthdr->nexthdr; + exthdr = (struct ipv6_opt_hdr *)(nh + offset); + break; + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + case IPPROTO_TCP: + case IPPROTO_SCTP: + case IPPROTO_DCCP: + if (!onlyproto && (nh + offset + 4 < skb->data || + pskb_may_pull(skb, nh + offset + 4 - skb->data))) { + __be16 *ports; + + nh = skb_network_header(skb); + ports = (__be16 *)(nh + offset); + fl6->fl6_sport = ports[!!reverse]; + fl6->fl6_dport = ports[!reverse]; + } + fl6->flowi6_proto = nexthdr; + return; + case IPPROTO_ICMPV6: + if (!onlyproto && (nh + offset + 2 < skb->data || + pskb_may_pull(skb, nh + offset + 2 - skb->data))) { + u8 *icmp; + + nh = skb_network_header(skb); + icmp = (u8 *)(nh + offset); + fl6->fl6_icmp_type = icmp[0]; + fl6->fl6_icmp_code = icmp[1]; + } + fl6->flowi6_proto = nexthdr; + return; +#if IS_ENABLED(CONFIG_IPV6_MIP6) + case IPPROTO_MH: + offset += ipv6_optlen(exthdr); + if (!onlyproto && (nh + offset + 3 < skb->data || + pskb_may_pull(skb, nh + offset + 3 - skb->data))) { + struct ip6_mh *mh; + + nh = skb_network_header(skb); + mh = (struct ip6_mh *)(nh + offset); + fl6->fl6_mh_type = mh->ip6mh_type; + } + fl6->flowi6_proto = nexthdr; + return; +#endif + /* XXX Why are there these headers? */ + case IPPROTO_AH: + case IPPROTO_ESP: + case IPPROTO_COMP: + default: + fl6->fl6_ipsec_spi = 0; + fl6->flowi6_proto = nexthdr; + return; + } + } +} +#endif + int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned int family, int reverse) { - const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); - int err; - - if (unlikely(afinfo == NULL)) + switch (family) { + case AF_INET: + decode_session4(skb, fl, reverse); + break; +#if IS_ENABLED(CONFIG_IPV6) + case AF_INET6: + decode_session6(skb, fl, reverse); + break; +#endif + default: return -EAFNOSUPPORT; + } - afinfo->decode_session(skb, fl, reverse); - - err = security_xfrm_decode_session(skb, &fl->flowi_secid); - rcu_read_unlock(); - return err; + return security_xfrm_decode_session(skb, &fl->flowi_secid); } EXPORT_SYMBOL(__xfrm_decode_session); -- cgit v1.2.3-55-g7522