Changeset 58613 in vbox for trunk/src/VBox/NetworkServices

Timestamp:

Nov 9, 2015 2:45:26 AM (9 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

103987

Message:

NAT/Net: Export pxtcp_pcb_accept_outbound() and use it to provide DNS
TCP proxy. For now we only try to connect to the first resolver,
since we simply hand off connection to pxtcp and there are currently
no hooks for us to retry connection to a different server.

Location:

trunk/src/VBox/NetworkServices/NAT

Files:

• pxdns.c (modified) (5 diffs)
• pxtcp.c (modified) (2 diffs)
• pxtcp.h (modified) (1 diff)

trunk/src/VBox/NetworkServices/NAT/pxdns.c

@@ -43 +43 @@
 #include "proxy.h"
 #include "proxy_pollmgr.h"
+#include "pxtcp.h"
 
 #include "lwip/sys.h"
 #include "lwip/tcpip.h"
+#include "lwip/ip_addr.h"
 #include "lwip/udp.h"
+#include "lwip/tcp.h"
 
 #ifndef RT_OS_WINDOWS
@@ -84 +87 @@
     struct udp_pcb *pcb6;
 
+    struct tcp_pcb *ltcp;
+
     size_t generation;
     size_t nresolvers;
@@ -177 +182 @@
 static void pxdns_create_resolver_sockaddrs(struct pxdns *pxdns,
                                             const char **nameservers);
+
+static err_t pxdns_accept_syn(void *arg, struct tcp_pcb *newpcb, struct pbuf *syn);
 
 static void pxdns_recv4(void *arg, struct udp_pcb *pcb, struct pbuf *p,
@@ -211 +218 @@
     LWIP_UNUSED_ARG(proxy_netif);
 
+    pxdns->ltcp = tcp_new();
+    if (pxdns->ltcp != NULL) {
+        tcp_bind_ip6(pxdns->ltcp, IP6_ADDR_ANY, 53);
+        pxdns->ltcp = tcp_listen_dual(pxdns->ltcp);
+        if (pxdns->ltcp != NULL) {
+            tcp_arg(pxdns->ltcp, pxdns);
+            tcp_accept_syn(pxdns->ltcp, pxdns_accept_syn);
+        }
+    }
+
     pxdns->pmhdl4.callback = pxdns_pmgr_pump;
     pxdns->pmhdl4.data = (void *)pxdns;
@@ -863 +880 @@
     pxdns_request_free(req);
 }
+
+
+/**
+ * TCP DNS proxy.  This kicks in for large replies that don't fit into
+ * 512 bytes of UDP payload.  Client will retry with TCP to get
+ * complete reply.
+ */
+static err_t
+pxdns_accept_syn(void *arg, struct tcp_pcb *newpcb, struct pbuf *syn)
+{
+    struct pxdns *pxdns = (struct pxdns *)arg;
+    union sockaddr_inet *si;
+    ipX_addr_t *dst;
+    u16_t dst_port;
+
+    tcp_accepted(pxdns->ltcp);
+
+    if (pxdns->nresolvers == 0) {
+        return ERR_CONN;
+    }
+
+    si = &pxdns->resolvers[0];
+
+    if (si->sa.sa_family == AF_INET6) {
+        dst = (ipX_addr_t *)&si->sin6.sin6_addr;
+        dst_port = ntohs(si->sin6.sin6_port);
+    }
+    else {
+        dst = (ipX_addr_t *)&si->sin.sin_addr;
+        dst_port = ntohs(si->sin.sin_port);
+    }
+
+    /*
+     * XXX: TODO: need to implement protocol hooks.  E.g. here if
+     * connect fails, we should try connecting to a different server.
+     */
+    return pxtcp_pcb_accept_outbound(newpcb, syn,
+               si->sa.sa_family == AF_INET6, dst, dst_port);
+}

trunk/src/VBox/NetworkServices/NAT/pxtcp.c

@@ -276 +276 @@
 static void pxtcp_pcb_err(void *, err_t);
 
-static err_t pxtcp_pcb_accept_outbound(struct tcp_pcb *, struct pbuf *, int, ipX_addr_t *, u16_t);
-
 static err_t pxtcp_pcb_forward_outbound(struct pxtcp *, struct pbuf *);
 static void pxtcp_pcb_forward_outbound_close(struct pxtcp *);
@@ -1012 +1010 @@
 
 
-static err_t
+err_t
 pxtcp_pcb_accept_outbound(struct tcp_pcb *newpcb, struct pbuf *p,
                           int is_ipv6, ipX_addr_t *dst_addr, u16_t dst_port)

trunk/src/VBox/NetworkServices/NAT/pxtcp.h

@@ -19 +19 @@
 #define _pxtcp_h_
 
+#include "lwip/err.h"
+#include "lwip/ip_addr.h"
+
+struct pbuf;
+struct tcp_pcb;
 struct pxtcp;
 struct fwspec;
+
+err_t pxtcp_pcb_accept_outbound(struct tcp_pcb *, struct pbuf *, int, ipX_addr_t *, u16_t);
 
 struct pxtcp *pxtcp_create_forwarded(SOCKET);