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Diffstat (limited to 'net/xfrm/xfrm_policy.c')
-rw-r--r--net/xfrm/xfrm_policy.c231
1 files changed, 222 insertions, 9 deletions
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 <linux/cpu.h>
#include <linux/audit.h>
#include <linux/rhashtable.h>
+#include <linux/if_tunnel.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/xfrm.h>
#include <net/ip.h>
+#if IS_ENABLED(CONFIG_IPV6_MIP6)
+#include <net/mip6.h>
+#endif
#ifdef CONFIG_XFRM_STATISTICS
#include <net/snmp.h>
#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);
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-30 02:50:23 +0300