SUNRPC: Remove duplicate universal address generation

RPC universal address generation is currently done in several places:
rpcb_clnt.c, nfs4proc.c xprtsock.c, and xprtrdma.c.  Remove the
redundant cases that convert a socket address to a universal
address.  The nfs4proc.c case takes a pre-formatted presentation
address string, not a socket address, so we'll leave that one.

Because the new uaddr constructor uses the recently introduced
rpc_ntop(), it now supports proper "::" shorthanding for IPv6
addresses.  This allows the kernel to register properly formed
universal addresses with the local rpcbind service, in _all_ cases.

The kernel can now also send properly formed universal addresses in
RPCB_GETADDR requests, and support link-local properly when
encoding and decoding IPv6 addresses.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 29 insertions, 19 deletions

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index ad1d7315c498..1fb1c070c19d 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -153,6 +153,7 @@ static void rpcb_map_release(void *data)
 
         rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
         xprt_put(map->r_xprt);
+        kfree(map->r_addr);
         kfree(map);
 }
 
@@ -299,12 +300,9 @@ static int rpcb_register_inet4(const struct sockaddr *sap,
         const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
         struct rpcbind_args *map = msg->rpc_argp;
         unsigned short port = ntohs(sin->sin_port);
-        char buf[32];
+        int result;
 
-        /* Construct AF_INET universal address */
-        snprintf(buf, sizeof(buf), "%pI4.%u.%u",
-                 &sin->sin_addr.s_addr, port >> 8, port & 0xff);
-        map->r_addr = buf;
+        map->r_addr = rpc_sockaddr2uaddr(sap);
 
         dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
                 "local rpcbind\n", (port ? "" : "un"),
@@ -315,7 +313,9 @@ static int rpcb_register_inet4(const struct sockaddr *sap,
         if (port)
                 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 
-        return rpcb_register_call(RPCBVERS_4, msg);
+        result = rpcb_register_call(RPCBVERS_4, msg);
+        kfree(map->r_addr);
+        return result;
 }
 
 /*
@@ -327,16 +327,9 @@ static int rpcb_register_inet6(const struct sockaddr *sap,
         const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap;
         struct rpcbind_args *map = msg->rpc_argp;
         unsigned short port = ntohs(sin6->sin6_port);
-        char buf[64];
+        int result;
 
-        /* Construct AF_INET6 universal address */
-        if (ipv6_addr_any(&sin6->sin6_addr))
-                snprintf(buf, sizeof(buf), "::.%u.%u",
-                                port >> 8, port & 0xff);
-        else
-                snprintf(buf, sizeof(buf), "%pI6.%u.%u",
-                         &sin6->sin6_addr, port >> 8, port & 0xff);
-        map->r_addr = buf;
+        map->r_addr = rpc_sockaddr2uaddr(sap);
 
         dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
                 "local rpcbind\n", (port ? "" : "un"),
@@ -347,7 +340,9 @@ static int rpcb_register_inet6(const struct sockaddr *sap,
         if (port)
                 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 
-        return rpcb_register_call(RPCBVERS_4, msg);
+        result = rpcb_register_call(RPCBVERS_4, msg);
+        kfree(map->r_addr);
+        return result;
 }
 
 static int rpcb_unregister_all_protofamilies(struct rpc_message *msg)
@@ -570,6 +565,7 @@ void rpcb_getport_async(struct rpc_task *task)
                 goto bailout_nofree;
         }
 
+        /* Parent transport's destination address */
         salen = rpc_peeraddr(clnt, sap, sizeof(addr));
 
         /* Don't ever use rpcbind v2 for AF_INET6 requests */
@@ -620,11 +616,22 @@ void rpcb_getport_async(struct rpc_task *task)
         map->r_prot = xprt->prot;
         map->r_port = 0;
         map->r_xprt = xprt_get(xprt);
-        map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
-        map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
-        map->r_owner = "";
         map->r_status = -EIO;
 
+        switch (bind_version) {
+        case RPCBVERS_4:
+        case RPCBVERS_3:
+                map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
+                map->r_addr = rpc_sockaddr2uaddr(sap);
+                map->r_owner = "";
+                break;
+        case RPCBVERS_2:
+                map->r_addr = NULL;
+                break;
+        default:
+                BUG();
+        }
+
         child = rpcb_call_async(rpcb_clnt, map, proc);
         rpc_release_client(rpcb_clnt);
         if (IS_ERR(child)) {
@@ -722,6 +729,9 @@ static int rpcb_decode_set(struct rpc_rqst *req, __be32 *p,
 static int rpcb_encode_getaddr(struct rpc_rqst *req, __be32 *p,
                                struct rpcbind_args *rpcb)
 {
+        if (rpcb->r_addr == NULL)
+                return -EIO;
+
         dprintk("RPC:       encoding rpcb request (%u, %u, %s)\n",
                         rpcb->r_prog, rpcb->r_vers, rpcb->r_addr);
         *p++ = htonl(rpcb->r_prog);