[IPSEC]: Fix inter address family IPsec tunnel handling.

Signed-off-by: Kazunori MIYAZAWA <kazunori@miyazawa.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

10 files changed, 113 insertions, 21 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 619c53bc3cd2..4e6f9568cbe7 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -204,6 +204,7 @@ struct xfrm_state
          * transformer. */
         const struct xfrm_type  *type;
         struct xfrm_mode        *inner_mode;
+        struct xfrm_mode        *inner_mode_iaf;
         struct xfrm_mode        *outer_mode;
 
         /* Security context */
@@ -387,6 +388,27 @@ enum {
 extern int xfrm_register_mode(struct xfrm_mode *mode, int family);
 extern int xfrm_unregister_mode(struct xfrm_mode *mode, int family);
 
+static inline int xfrm_af2proto(unsigned int family)
+{
+        switch(family) {
+        case AF_INET:
+                return IPPROTO_IPIP;
+        case AF_INET6:
+                return IPPROTO_IPV6;
+        default:
+                return 0;
+        }
+}
+
+static inline struct xfrm_mode *xfrm_ip2inner_mode(struct xfrm_state *x, int ipproto)
+{
+        if ((ipproto == IPPROTO_IPIP && x->props.family == AF_INET) ||
+            (ipproto == IPPROTO_IPV6 && x->props.family == AF_INET6))
+                return x->inner_mode;
+        else
+                return x->inner_mode_iaf;
+}
+
 struct xfrm_tmpl
 {
 /* id in template is interpreted as:
@@ -1253,6 +1275,7 @@ extern int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi,
 extern int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
 extern int xfrm_output_resume(struct sk_buff *skb, int err);
 extern int xfrm_output(struct sk_buff *skb);
+extern int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb);
 extern int xfrm4_extract_header(struct sk_buff *skb);
 extern int xfrm4_extract_input(struct xfrm_state *x, struct sk_buff *skb);
 extern int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
diff --git a/net/ipv4/xfrm4_mode_tunnel.c b/net/ipv4/xfrm4_mode_tunnel.c
index 8dee617ee900..584e6d74e3a9 100644
--- a/net/ipv4/xfrm4_mode_tunnel.c
+++ b/net/ipv4/xfrm4_mode_tunnel.c
@@ -41,7 +41,7 @@ static int xfrm4_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
         top_iph->ihl = 5;
         top_iph->version = 4;
 
-        top_iph->protocol = x->inner_mode->afinfo->proto;
+        top_iph->protocol = xfrm_af2proto(skb->dst->ops->family);
 
         /* DS disclosed */
         top_iph->tos = INET_ECN_encapsulate(XFRM_MODE_SKB_CB(skb)->tos,
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index d5a58a818021..8c3180adddbf 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -56,7 +56,7 @@ int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 {
         int err;
 
-        err = x->inner_mode->afinfo->extract_output(x, skb);
+        err = xfrm_inner_extract_output(x, skb);
         if (err)
                 return err;
 
diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c
index 0c742faaa30b..e20529b4c825 100644
--- a/net/ipv6/xfrm6_mode_tunnel.c
+++ b/net/ipv6/xfrm6_mode_tunnel.c
@@ -45,7 +45,7 @@ static int xfrm6_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 
         memcpy(top_iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl,
                sizeof(top_iph->flow_lbl));
-        top_iph->nexthdr = x->inner_mode->afinfo->proto;
+        top_iph->nexthdr = xfrm_af2proto(skb->dst->ops->family);
 
         dsfield = XFRM_MODE_SKB_CB(skb)->tos;
         dsfield = INET_ECN_encapsulate(dsfield, dsfield);
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 79ccfb080733..0af823cf7f1f 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -62,7 +62,7 @@ int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 {
         int err;
 
-        err = x->inner_mode->afinfo->extract_output(x, skb);
+        err = xfrm_inner_extract_output(x, skb);
         if (err)
                 return err;
 
diff --git a/net/key/af_key.c b/net/key/af_key.c
index 8b5f486ac80f..e9ef9af4a53b 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -1219,7 +1219,7 @@ static struct xfrm_state * pfkey_msg2xfrm_state(struct sadb_msg *hdr,
                 x->sel.prefixlen_s = addr->sadb_address_prefixlen;
         }
 
-        if (!x->sel.family)
+        if (x->props.mode == XFRM_MODE_TRANSPORT)
                 x->sel.family = x->props.family;
 
         if (ext_hdrs[SADB_X_EXT_NAT_T_TYPE-1]) {
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 62188c6a06dd..75279402ccf4 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -84,14 +84,21 @@ int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
 
 int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 {
+        struct xfrm_mode *inner_mode = x->inner_mode;
         int err;
 
         err = x->outer_mode->afinfo->extract_input(x, skb);
         if (err)
                 return err;
 
-        skb->protocol = x->inner_mode->afinfo->eth_proto;
-        return x->inner_mode->input2(x, skb);
+        if (x->sel.family == AF_UNSPEC) {
+                inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
+                if (inner_mode == NULL)
+                        return -EAFNOSUPPORT;
+        }
+
+        skb->protocol = inner_mode->afinfo->eth_proto;
+        return inner_mode->input2(x, skb);
 }
 EXPORT_SYMBOL(xfrm_prepare_input);
 
@@ -101,6 +108,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
         __be32 seq;
         struct xfrm_state *x;
         xfrm_address_t *daddr;
+        struct xfrm_mode *inner_mode;
         unsigned int family;
         int decaps = 0;
         int async = 0;
@@ -207,7 +215,15 @@ resume:
 
                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 
-                if (x->inner_mode->input(x, skb)) {
+                inner_mode = x->inner_mode;
+
+                if (x->sel.family == AF_UNSPEC) {
+                        inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
+                        if (inner_mode == NULL)
+                                goto drop;
+                }
+
+                if (inner_mode->input(x, skb)) {
                         XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEMODEERROR);
                         goto drop;
                 }
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 569d377932c4..2519129c6d21 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -124,7 +124,7 @@ int xfrm_output_resume(struct sk_buff *skb, int err)
                 if (!x)
                         return dst_output(skb);
 
-                err = nf_hook(x->inner_mode->afinfo->family,
+                err = nf_hook(skb->dst->ops->family,
                               NF_INET_POST_ROUTING, skb,
                               NULL, skb->dst->dev, xfrm_output2);
                 if (unlikely(err != 1))
@@ -193,4 +193,20 @@ int xfrm_output(struct sk_buff *skb)
 
         return xfrm_output2(skb);
 }
+
+int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+        struct xfrm_mode *inner_mode;
+        if (x->sel.family == AF_UNSPEC)
+                inner_mode = xfrm_ip2inner_mode(x,
+                                xfrm_af2proto(skb->dst->ops->family));
+        else
+                inner_mode = x->inner_mode;
+
+        if (inner_mode == NULL)
+                return -EAFNOSUPPORT;
+        return inner_mode->afinfo->extract_output(x, skb);
+}
+
 EXPORT_SYMBOL_GPL(xfrm_output);
+EXPORT_SYMBOL_GPL(xfrm_inner_extract_output);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 7ba65e82941c..58f1f9347b54 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -388,6 +388,8 @@ static void xfrm_state_gc_destroy(struct xfrm_state *x)
         kfree(x->coaddr);
         if (x->inner_mode)
                 xfrm_put_mode(x->inner_mode);
+        if (x->inner_mode_iaf)
+                xfrm_put_mode(x->inner_mode_iaf);
         if (x->outer_mode)
                 xfrm_put_mode(x->outer_mode);
         if (x->type) {
@@ -523,6 +525,8 @@ struct xfrm_state *xfrm_state_alloc(void)
                 x->lft.hard_packet_limit = XFRM_INF;
                 x->replay_maxage = 0;
                 x->replay_maxdiff = 0;
+                x->inner_mode = NULL;
+                x->inner_mode_iaf = NULL;
                 spin_lock_init(&x->lock);
         }
         return x;
@@ -796,7 +800,7 @@ xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
                               selector.
                          */
                         if (x->km.state == XFRM_STATE_VALID) {
-                                if (!xfrm_selector_match(&x->sel, fl, x->sel.family) ||
+                                if ((x->sel.family && !xfrm_selector_match(&x->sel, fl, x->sel.family)) ||
                                     !security_xfrm_state_pol_flow_match(x, pol, fl))
                                         continue;
                                 if (!best ||
@@ -1944,6 +1948,7 @@ int xfrm_state_mtu(struct xfrm_state *x, int mtu)
 int xfrm_init_state(struct xfrm_state *x)
 {
         struct xfrm_state_afinfo *afinfo;
+        struct xfrm_mode *inner_mode;
         int family = x->props.family;
         int err;
 
@@ -1962,13 +1967,48 @@ int xfrm_init_state(struct xfrm_state *x)
                 goto error;
 
         err = -EPROTONOSUPPORT;
-        x->inner_mode = xfrm_get_mode(x->props.mode, x->sel.family);
-        if (x->inner_mode == NULL)
-                goto error;
 
-        if (!(x->inner_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
-            family != x->sel.family)
-                goto error;
+        if (x->sel.family != AF_UNSPEC) {
+                inner_mode = xfrm_get_mode(x->props.mode, x->sel.family);
+                if (inner_mode == NULL)
+                        goto error;
+
+                if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
+                    family != x->sel.family) {
+                        xfrm_put_mode(inner_mode);
+                        goto error;
+                }
+
+                x->inner_mode = inner_mode;
+        } else {
+                struct xfrm_mode *inner_mode_iaf;
+
+                inner_mode = xfrm_get_mode(x->props.mode, AF_INET);
+                if (inner_mode == NULL)
+                        goto error;
+
+                if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL)) {
+                        xfrm_put_mode(inner_mode);
+                        goto error;
+                }
+
+                inner_mode_iaf = xfrm_get_mode(x->props.mode, AF_INET6);
+                if (inner_mode_iaf == NULL)
+                        goto error;
+
+                if (!(inner_mode_iaf->flags & XFRM_MODE_FLAG_TUNNEL)) {
+                        xfrm_put_mode(inner_mode_iaf);
+                        goto error;
+                }
+
+                if (x->props.family == AF_INET) {
+                        x->inner_mode = inner_mode;
+                        x->inner_mode_iaf = inner_mode_iaf;
+                } else {
+                        x->inner_mode = inner_mode_iaf;
+                        x->inner_mode_iaf = inner_mode;
+                }
+        }
 
         x->type = xfrm_get_type(x->id.proto, family);
         if (x->type == NULL)
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index f971ca5645f8..5d96f2728dc6 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -288,12 +288,9 @@ static void copy_from_user_state(struct xfrm_state *x, struct xfrm_usersa_info *
         memcpy(&x->props.saddr, &p->saddr, sizeof(x->props.saddr));
         x->props.flags = p->flags;
 
-        /*
-         * Set inner address family if the KM left it as zero.
-         * See comment in validate_tmpl.
-         */
-        if (!x->sel.family)
+        if (x->props.mode == XFRM_MODE_TRANSPORT)
                 x->sel.family = p->family;
+
 }
 
 /*