Merge remote-tracking branch 'kiszka/queues/slirp' into staging

# By Bas van Sisseren (1) and Gertjan Halkes (1)
# Via Jan Kiszka
* kiszka/queues/slirp:
  make user networking hostfwd work with restrict=y
  fix -net user checks by reordering checks

Message-id: cover.1371638848.git.jan.kiszka@siemens.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

net/slirp.c

@@ -212,19 +212,19 @@ static int net_slirp_init(NetClientState *peer, const char *model,
         return -1;
     }
 
-    if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
+    if (vnameserver && !inet_aton(vnameserver, &dns)) {
         return -1;
     }
-    if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
-        dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
+    if ((dns.s_addr & mask.s_addr) != net.s_addr ||
+        dns.s_addr == host.s_addr) {
         return -1;
     }
 
-    if (vnameserver && !inet_aton(vnameserver, &dns)) {
+    if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
         return -1;
     }
-    if ((dns.s_addr & mask.s_addr) != net.s_addr ||
-        dns.s_addr == host.s_addr) {
+    if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
+        dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
         return -1;
     }
 

slirp/tcp_input.c

@@ -316,16 +316,6 @@ tcp_input(struct mbuf *m, int iphlen, struct socket *inso)
 	m->m_data += sizeof(struct tcpiphdr)+off-sizeof(struct tcphdr);
 	m->m_len  -= sizeof(struct tcpiphdr)+off-sizeof(struct tcphdr);
 
-    if (slirp->restricted) {
-        for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
-            if (ex_ptr->ex_fport == ti->ti_dport &&
-                ti->ti_dst.s_addr == ex_ptr->ex_addr.s_addr) {
-                break;
-            }
-        }
-        if (!ex_ptr)
-            goto drop;
-    }
 	/*
 	 * Locate pcb for segment.
 	 */
@@ -355,6 +345,22 @@ findso:
 	 * as if it was LISTENING, and continue...
 	 */
         if (so == NULL) {
+          if (slirp->restricted) {
+            /* Any hostfwds will have an existing socket, so we only get here
+             * for non-hostfwd connections. These should be dropped, unless it
+             * happens to be a guestfwd.
+             */
+            for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
+                if (ex_ptr->ex_fport == ti->ti_dport &&
+                    ti->ti_dst.s_addr == ex_ptr->ex_addr.s_addr) {
+                    break;
+                }
+            }
+            if (!ex_ptr) {
+                goto dropwithreset;
+            }
+          }
+
 	  if ((tiflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) != TH_SYN)
 	    goto dropwithreset;