IB/addr: Fix IPv6 routing lookup

Include link scope as part of address resolution.  Combine local
and remote address resolution into a single, simpler code path.
Fix error checking in the IPv6 routing lookups.

Based on work from:
David Wilder <dwilder@us.ibm.com>
Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

Signed-off-by: Sean Hefty <sean.hefty@intel.com>

[ Fix up cma_check_linklocal() for !IPV6 case.  - Roland ]

Signed-off-by: Roland Dreier <rolandd@cisco.com>

2 files changed, 74 insertions, 117 deletions

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index 38a7184ea745..abbb06996f9e 100644
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -176,34 +176,6 @@ static void queue_req(struct addr_req *req)
         mutex_unlock(&lock);
 }
 
-static void addr_send_arp(struct sockaddr *dst_in)
-{
-        struct rtable *rt;
-        struct flowi fl;
-
-        memset(&fl, 0, sizeof fl);
-
-        switch (dst_in->sa_family) {
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-        case AF_INET6:
-        {
-                struct dst_entry *dst;
-
-                fl.nl_u.ip6_u.daddr =
-                        ((struct sockaddr_in6 *) dst_in)->sin6_addr;
-
-                dst = ip6_route_output(&init_net, NULL, &fl);
-                if (!dst)
-                        return;
-
-                neigh_event_send(dst->neighbour, NULL);
-                dst_release(dst);
-                break;
-        }
-#endif
-        }
-}
-
 static int addr4_resolve(struct sockaddr_in *src_in,
                          struct sockaddr_in *dst_in,
                          struct rdma_dev_addr *addr)
@@ -259,39 +231,63 @@ out:
 }
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static int addr6_resolve_remote(struct sockaddr_in6 *src_in,
-                               struct sockaddr_in6 *dst_in,
-                               struct rdma_dev_addr *addr)
+static int addr6_resolve(struct sockaddr_in6 *src_in,
+                         struct sockaddr_in6 *dst_in,
+                         struct rdma_dev_addr *addr)
 {
         struct flowi fl;
         struct neighbour *neigh;
         struct dst_entry *dst;
-        int ret = -ENODATA;
+        int ret;
 
         memset(&fl, 0, sizeof fl);
-        fl.nl_u.ip6_u.daddr = dst_in->sin6_addr;
-        fl.nl_u.ip6_u.saddr = src_in->sin6_addr;
+        ipv6_addr_copy(&fl.fl6_dst, &dst_in->sin6_addr);
+        ipv6_addr_copy(&fl.fl6_src, &src_in->sin6_addr);
         fl.oif = addr->bound_dev_if;
 
         dst = ip6_route_output(&init_net, NULL, &fl);
-        if (!dst)
-                return ret;
+        if ((ret = dst->error))
+                goto put;
+
+        if (ipv6_addr_any(&fl.fl6_src)) {
+                ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
+                                         &fl.fl6_dst, 0, &fl.fl6_src);
+                if (ret)
+                        goto put;
 
+                src_in->sin6_family = AF_INET6;
+                ipv6_addr_copy(&src_in->sin6_addr, &fl.fl6_src);
+        }
+
+        if (dst->dev->flags & IFF_LOOPBACK) {
+                ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
+                if (!ret)
+                        memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
+                goto put;
+        }
+
+        /* If the device does ARP internally, return 'done' */
         if (dst->dev->flags & IFF_NOARP) {
                 ret = rdma_copy_addr(addr, dst->dev, NULL);
-        } else {
-                neigh = dst->neighbour;
-                if (neigh && (neigh->nud_state & NUD_VALID))
-                        ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
+                goto put;
         }
 
+        neigh = dst->neighbour;
+        if (!neigh || !(neigh->nud_state & NUD_VALID)) {
+                neigh_event_send(dst->neighbour, NULL);
+                ret = -ENODATA;
+                goto put;
+        }
+
+        ret = rdma_copy_addr(addr, dst->dev, neigh->ha);
+put:
         dst_release(dst);
         return ret;
 }
 #else
-static int addr6_resolve_remote(struct sockaddr_in6 *src_in,
-                               struct sockaddr_in6 *dst_in,
-                               struct rdma_dev_addr *addr)
+static int addr6_resolve(struct sockaddr_in6 *src_in,
+                         struct sockaddr_in6 *dst_in,
+                         struct rdma_dev_addr *addr)
 {
         return -EADDRNOTAVAIL;
 }
@@ -305,7 +301,7 @@ static int addr_resolve(struct sockaddr *src_in,
                 return addr4_resolve((struct sockaddr_in *) src_in,
                         (struct sockaddr_in *) dst_in, addr);
         } else
-                return addr6_resolve_remote((struct sockaddr_in6 *) src_in,
+                return addr6_resolve((struct sockaddr_in6 *) src_in,
                         (struct sockaddr_in6 *) dst_in, addr);
 }
 
@@ -346,60 +342,6 @@ static void process_req(struct work_struct *work)
         }
 }
 
-static int addr_resolve_local(struct sockaddr *src_in,
-                              struct sockaddr *dst_in,
-                              struct rdma_dev_addr *addr)
-{
-        struct net_device *dev;
-        int ret;
-
-        switch (dst_in->sa_family) {
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-        case AF_INET6:
-        {
-                struct in6_addr *a;
-
-                read_lock(&dev_base_lock);
-                for_each_netdev(&init_net, dev)
-                        if (ipv6_chk_addr(&init_net,
-                                          &((struct sockaddr_in6 *) dst_in)->sin6_addr,
-                                          dev, 1))
-                                break;
-
-                if (!dev) {
-                        read_unlock(&dev_base_lock);
-                        return -EADDRNOTAVAIL;
-                }
-
-                a = &((struct sockaddr_in6 *) src_in)->sin6_addr;
-
-                if (ipv6_addr_any(a)) {
-                        src_in->sa_family = dst_in->sa_family;
-                        ((struct sockaddr_in6 *) src_in)->sin6_addr =
-                                ((struct sockaddr_in6 *) dst_in)->sin6_addr;
-                        ret = rdma_copy_addr(addr, dev, dev->dev_addr);
-                } else if (ipv6_addr_loopback(a)) {
-                        ret = rdma_translate_ip(dst_in, addr);
-                        if (!ret)
-                                memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
-                } else  {
-                        ret = rdma_translate_ip(src_in, addr);
-                        if (!ret)
-                                memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
-                }
-                read_unlock(&dev_base_lock);
-                break;
-        }
-#endif
-
-        default:
-                ret = -EADDRNOTAVAIL;
-                break;
-        }
-
-        return ret;
-}
-
 int rdma_resolve_ip(struct rdma_addr_client *client,
                     struct sockaddr *src_addr, struct sockaddr *dst_addr,
                     struct rdma_dev_addr *addr, int timeout_ms,
@@ -436,10 +378,7 @@ int rdma_resolve_ip(struct rdma_addr_client *client,
         req->client = client;
         atomic_inc(&client->refcount);
 
-        req->status = addr_resolve_local(src_in, dst_in, addr);
-        if (req->status == -EADDRNOTAVAIL)
-                req->status = addr_resolve(src_in, dst_in, addr);
-
+        req->status = addr_resolve(src_in, dst_in, addr);
         switch (req->status) {
         case 0:
                 req->timeout = jiffies;
@@ -448,7 +387,6 @@ int rdma_resolve_ip(struct rdma_addr_client *client,
         case -ENODATA:
                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
                 queue_req(req);
-                addr_send_arp(dst_in);
                 break;
         default:
                 ret = req->status;
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 38867a46d39e..fbdd73106000 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -1472,15 +1472,6 @@ static void cma_listen_on_all(struct rdma_id_private *id_priv)
         mutex_unlock(&lock);
 }
 
-static int cma_bind_any(struct rdma_cm_id *id, sa_family_t af)
-{
-        struct sockaddr_storage addr_in;
-
-        memset(&addr_in, 0, sizeof addr_in);
-        addr_in.ss_family = af;
-        return rdma_bind_addr(id, (struct sockaddr *) &addr_in);
-}
-
 int rdma_listen(struct rdma_cm_id *id, int backlog)
 {
         struct rdma_id_private *id_priv;
@@ -1488,7 +1479,8 @@ int rdma_listen(struct rdma_cm_id *id, int backlog)
 
         id_priv = container_of(id, struct rdma_id_private, id);
         if (id_priv->state == CMA_IDLE) {
-                ret = cma_bind_any(id, AF_INET);
+                ((struct sockaddr *) &id->route.addr.src_addr)->sa_family = AF_INET;
+                ret = rdma_bind_addr(id, (struct sockaddr *) &id->route.addr.src_addr);
                 if (ret)
                         return ret;
         }
@@ -1885,10 +1877,14 @@ err:
 static int cma_bind_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
                          struct sockaddr *dst_addr)
 {
-        if (src_addr && src_addr->sa_family)
-                return rdma_bind_addr(id, src_addr);
-        else
-                return cma_bind_any(id, dst_addr->sa_family);
+        if (!src_addr || !src_addr->sa_family) {
+                src_addr = (struct sockaddr *) &id->route.addr.src_addr;
+                if ((src_addr->sa_family = dst_addr->sa_family) == AF_INET6) {
+                        ((struct sockaddr_in6 *) src_addr)->sin6_scope_id =
+                                ((struct sockaddr_in6 *) dst_addr)->sin6_scope_id;
+                }
+        }
+        return rdma_bind_addr(id, src_addr);
 }
 
 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
@@ -2084,6 +2080,25 @@ static int cma_get_port(struct rdma_id_private *id_priv)
         return ret;
 }
 
+static int cma_check_linklocal(struct rdma_dev_addr *dev_addr,
+                               struct sockaddr *addr)
+{
+#if defined(CONFIG_IPv6) || defined(CONFIG_IPV6_MODULE)
+        struct sockaddr_in6 *sin6;
+
+        if (addr->sa_family != AF_INET6)
+                return 0;
+
+        sin6 = (struct sockaddr_in6 *) addr;
+        if ((ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
+            !sin6->sin6_scope_id)
+                        return -EINVAL;
+
+        dev_addr->bound_dev_if = sin6->sin6_scope_id;
+#endif
+        return 0;
+}
+
 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
 {
         struct rdma_id_private *id_priv;
@@ -2096,6 +2111,10 @@ int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
         if (!cma_comp_exch(id_priv, CMA_IDLE, CMA_ADDR_BOUND))
                 return -EINVAL;
 
+        ret = cma_check_linklocal(&id->route.addr.dev_addr, addr);
+        if (ret)
+                goto err1;
+
         if (cma_loopback_addr(addr)) {
                 ret = cma_bind_loopback(id_priv);
         } else if (!cma_zero_addr(addr)) {