net: Put flowi_* prefix on AF independent members of struct flowi
[linux-3.10.git] / net / sctp / bind_addr.c
index 80294cb..faf71d1 100644 (file)
@@ -1,20 +1,20 @@
-/* SCTP kernel reference Implementation
+/* SCTP kernel implementation
  * (C) Copyright IBM Corp. 2001, 2003
  * Copyright (c) Cisco 1999,2000
  * Copyright (c) Motorola 1999,2000,2001
  * Copyright (c) La Monte H.P. Yarroll 2001
  *
- * This file is part of the SCTP kernel reference implementation.
+ * This file is part of the SCTP kernel implementation.
  *
  * A collection class to handle the storage of transport addresses.
  *
- * The SCTP reference implementation is free software;
+ * This SCTP implementation is free software;
  * you can redistribute it and/or modify it under the terms of
  * the GNU General Public License as published by
  * the Free Software Foundation; either version 2, or (at your option)
  * any later version.
  *
- * The SCTP reference implementation is distributed in the hope that it
+ * This SCTP implementation is distributed in the hope that it
  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  *                 ************************
  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
@@ -43,7 +43,7 @@
  */
 
 #include <linux/types.h>
-#include <linux/sched.h>
+#include <linux/slab.h>
 #include <linux/in.h>
 #include <net/sock.h>
 #include <net/ipv6.h>
@@ -68,15 +68,13 @@ int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
                        int flags)
 {
        struct sctp_sockaddr_entry *addr;
-       struct list_head *pos;
        int error = 0;
 
        /* All addresses share the same port.  */
        dest->port = src->port;
 
        /* Extract the addresses which are relevant for this scope.  */
-       list_for_each(pos, &src->address_list) {
-               addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+       list_for_each_entry(addr, &src->address_list, list) {
                error = sctp_copy_one_addr(dest, &addr->a, scope,
                                           gfp, flags);
                if (error < 0)
@@ -88,9 +86,7 @@ int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
         * the assumption that we must be sitting behind a NAT.
         */
        if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
-               list_for_each(pos, &src->address_list) {
-                       addr = list_entry(pos, struct sctp_sockaddr_entry,
-                                         list);
+               list_for_each_entry(addr, &src->address_list, list) {
                        error = sctp_copy_one_addr(dest, &addr->a,
                                                   SCTP_SCOPE_LINK, gfp,
                                                   flags);
@@ -106,6 +102,30 @@ out:
        return error;
 }
 
+/* Exactly duplicate the address lists.  This is necessary when doing
+ * peer-offs and accepts.  We don't want to put all the current system
+ * addresses into the endpoint.  That's useless.  But we do want duplicat
+ * the list of bound addresses that the older endpoint used.
+ */
+int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
+                       const struct sctp_bind_addr *src,
+                       gfp_t gfp)
+{
+       struct sctp_sockaddr_entry *addr;
+       int error = 0;
+
+       /* All addresses share the same port.  */
+       dest->port = src->port;
+
+       list_for_each_entry(addr, &src->address_list, list) {
+               error = sctp_add_bind_addr(dest, &addr->a, 1, gfp);
+               if (error < 0)
+                       break;
+       }
+
+       return error;
+}
+
 /* Initialize the SCTP_bind_addr structure for either an endpoint or
  * an association.
  */
@@ -146,7 +166,7 @@ void sctp_bind_addr_free(struct sctp_bind_addr *bp)
 
 /* Add an address to the bind address list in the SCTP_bind_addr structure. */
 int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
-                      __u8 use_as_src, gfp_t gfp)
+                      __u8 addr_state, gfp_t gfp)
 {
        struct sctp_sockaddr_entry *addr;
 
@@ -163,10 +183,15 @@ int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
        if (!addr->a.v4.sin_port)
                addr->a.v4.sin_port = htons(bp->port);
 
-       addr->use_as_src = use_as_src;
+       addr->state = addr_state;
+       addr->valid = 1;
 
        INIT_LIST_HEAD(&addr->list);
-       list_add_tail(&addr->list, &bp->address_list);
+
+       /* We always hold a socket lock when calling this function,
+        * and that acts as a writer synchronizing lock.
+        */
+       list_add_tail_rcu(&addr->list, &bp->address_list);
        SCTP_DBG_OBJCNT_INC(addr);
 
        return 0;
@@ -177,21 +202,28 @@ int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
  */
 int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
 {
-       struct list_head *pos, *temp;
-       struct sctp_sockaddr_entry *addr;
+       struct sctp_sockaddr_entry *addr, *temp;
+       int found = 0;
 
-       list_for_each_safe(pos, temp, &bp->address_list) {
-               addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+       /* We hold the socket lock when calling this function,
+        * and that acts as a writer synchronizing lock.
+        */
+       list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
                if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
                        /* Found the exact match. */
-                       list_del(pos);
-                       kfree(addr);
-                       SCTP_DBG_OBJCNT_DEC(addr);
-
-                       return 0;
+                       found = 1;
+                       addr->valid = 0;
+                       list_del_rcu(&addr->list);
+                       break;
                }
        }
 
+       if (found) {
+               call_rcu(&addr->rcu, sctp_local_addr_free);
+               SCTP_DBG_OBJCNT_DEC(addr);
+               return 0;
+       }
+
        return -EINVAL;
 }
 
@@ -235,8 +267,7 @@ union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
 
        addrparms = retval;
 
-       list_for_each(pos, &bp->address_list) {
-               addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+       list_for_each_entry(addr, &bp->address_list, list) {
                af = sctp_get_af_specific(addr->a.v4.sin_family);
                len = af->to_addr_param(&addr->a, &rawaddr);
                memcpy(addrparms.v, &rawaddr, len);
@@ -276,7 +307,7 @@ int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
                }
 
                af->from_addr_param(&addr, rawaddr, htons(port), 0);
-               retval = sctp_add_bind_addr(bp, &addr, 1, gfp);
+               retval = sctp_add_bind_addr(bp, &addr, SCTP_ADDR_SRC, gfp);
                if (retval) {
                        /* Can't finish building the list, clean up. */
                        sctp_bind_addr_clean(bp);
@@ -301,15 +332,83 @@ int sctp_bind_addr_match(struct sctp_bind_addr *bp,
                         struct sctp_sock *opt)
 {
        struct sctp_sockaddr_entry *laddr;
-       struct list_head *pos;
+       int match = 0;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+               if (!laddr->valid)
+                       continue;
+               if (opt->pf->cmp_addr(&laddr->a, addr, opt)) {
+                       match = 1;
+                       break;
+               }
+       }
+       rcu_read_unlock();
 
-       list_for_each(pos, &bp->address_list) {
-               laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
-               if (opt->pf->cmp_addr(&laddr->a, addr, opt))
-                       return 1;
+       return match;
+}
+
+/* Does the address 'addr' conflict with any addresses in
+ * the bp.
+ */
+int sctp_bind_addr_conflict(struct sctp_bind_addr *bp,
+                           const union sctp_addr *addr,
+                           struct sctp_sock *bp_sp,
+                           struct sctp_sock *addr_sp)
+{
+       struct sctp_sockaddr_entry *laddr;
+       int conflict = 0;
+       struct sctp_sock *sp;
+
+       /* Pick the IPv6 socket as the basis of comparison
+        * since it's usually a superset of the IPv4.
+        * If there is no IPv6 socket, then default to bind_addr.
+        */
+       if (sctp_opt2sk(bp_sp)->sk_family == AF_INET6)
+               sp = bp_sp;
+       else if (sctp_opt2sk(addr_sp)->sk_family == AF_INET6)
+               sp = addr_sp;
+       else
+               sp = bp_sp;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+               if (!laddr->valid)
+                       continue;
+
+               conflict = sp->pf->cmp_addr(&laddr->a, addr, sp);
+               if (conflict)
+                       break;
        }
+       rcu_read_unlock();
 
-       return 0;
+       return conflict;
+}
+
+/* Get the state of the entry in the bind_addr_list */
+int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
+                        const union sctp_addr *addr)
+{
+       struct sctp_sockaddr_entry *laddr;
+       struct sctp_af *af;
+       int state = -1;
+
+       af = sctp_get_af_specific(addr->sa.sa_family);
+       if (unlikely(!af))
+               return state;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+               if (!laddr->valid)
+                       continue;
+               if (af->cmp_addr(&laddr->a, addr)) {
+                       state = laddr->state;
+                       break;
+               }
+       }
+       rcu_read_unlock();
+
+       return state;
 }
 
 /* Find the first address in the bind address list that is not present in
@@ -324,18 +423,19 @@ union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr     *bp,
        union sctp_addr                 *addr;
        void                            *addr_buf;
        struct sctp_af                  *af;
-       struct list_head                *pos;
        int                             i;
 
-       list_for_each(pos, &bp->address_list) {
-               laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
-
+       /* This is only called sctp_send_asconf_del_ip() and we hold
+        * the socket lock in that code patch, so that address list
+        * can't change.
+        */
+       list_for_each_entry(laddr, &bp->address_list, list) {
                addr_buf = (union sctp_addr *)addrs;
                for (i = 0; i < addrcnt; i++) {
                        addr = (union sctp_addr *)addr_buf;
                        af = sctp_get_af_specific(addr->v4.sin_family);
                        if (!af)
-                               return NULL;
+                               break;
 
                        if (opt->pf->cmp_addr(&laddr->a, addr, opt))
                                break;
@@ -357,7 +457,7 @@ static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
 {
        int error = 0;
 
-       if (sctp_is_any(addr)) {
+       if (sctp_is_any(NULL, addr)) {
                error = sctp_copy_local_addr_list(dest, scope, gfp, flags);
        } else if (sctp_in_scope(addr, scope)) {
                /* Now that the address is in scope, check to see if
@@ -369,18 +469,29 @@ static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
                    (((AF_INET6 == addr->sa.sa_family) &&
                      (flags & SCTP_ADDR6_ALLOWED) &&
                      (flags & SCTP_ADDR6_PEERSUPP))))
-                       error = sctp_add_bind_addr(dest, addr, 1, gfp);
+                       error = sctp_add_bind_addr(dest, addr, SCTP_ADDR_SRC,
+                                                   gfp);
        }
 
        return error;
 }
 
 /* Is this a wildcard address?  */
-int sctp_is_any(const union sctp_addr *addr)
+int sctp_is_any(struct sock *sk, const union sctp_addr *addr)
 {
-       struct sctp_af *af = sctp_get_af_specific(addr->sa.sa_family);
+       unsigned short fam = 0;
+       struct sctp_af *af;
+
+       /* Try to get the right address family */
+       if (addr->sa.sa_family != AF_UNSPEC)
+               fam = addr->sa.sa_family;
+       else if (sk)
+               fam = sk->sk_family;
+
+       af = sctp_get_af_specific(fam);
        if (!af)
                return 0;
+
        return af->is_any(addr);
 }
 
@@ -399,9 +510,28 @@ int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
         * of requested destination address, sender and receiver
         * SHOULD include all of its addresses with level greater
         * than or equal to L.
+        *
+        * Address scoping can be selectively controlled via sysctl
+        * option
         */
-       if (addr_scope <= scope)
+       switch (sctp_scope_policy) {
+       case SCTP_SCOPE_POLICY_DISABLE:
                return 1;
+       case SCTP_SCOPE_POLICY_ENABLE:
+               if (addr_scope <= scope)
+                       return 1;
+               break;
+       case SCTP_SCOPE_POLICY_PRIVATE:
+               if (addr_scope <= scope || SCTP_SCOPE_PRIVATE == addr_scope)
+                       return 1;
+               break;
+       case SCTP_SCOPE_POLICY_LINK:
+               if (addr_scope <= scope || SCTP_SCOPE_LINK == addr_scope)
+                       return 1;
+               break;
+       default:
+               break;
+       }
 
        return 0;
 }