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Diffstat (limited to 'slirp-android/tcp_subr.c')
-rw-r--r--slirp-android/tcp_subr.c169
1 files changed, 140 insertions, 29 deletions
diff --git a/slirp-android/tcp_subr.c b/slirp-android/tcp_subr.c
index b8b680c..0550d4b 100644
--- a/slirp-android/tcp_subr.c
+++ b/slirp-android/tcp_subr.c
@@ -377,6 +377,29 @@ tcp_proxy_event( struct socket* so,
tcp_input(NULL, sizeof(struct ip), so);
}
+
+/* Tests if an IP address corresponds to a special Qemu service (eg, the DNS
+ * server or the gateway - see ctl.h) and if so, rewrites it with the real
+ * address of the service.
+ */
+int is_qemu_special_address(unsigned long dst_addr, unsigned long *redir_addr)
+{
+ if ((dst_addr & htonl(0xffffff00)) == special_addr_ip) {
+ /* It's an alias */
+
+ int last_byte = dst_addr & 0xff;
+
+ if (CTL_IS_DNS(last_byte))
+ *redir_addr = dns_addr[last_byte - CTL_DNS];
+ else
+ *redir_addr = loopback_addr_ip;
+
+ return 1;
+ }
+ return 0;
+}
+
+
/*
* Connect to a host on the Internet
* Called by tcp_input
@@ -390,41 +413,56 @@ tcp_proxy_event( struct socket* so,
int tcp_fconnect(struct socket *so)
{
int ret=0;
- int try_proxy = 1;
SockAddress sockaddr;
- uint32_t sock_ip;
- uint16_t sock_port;
+ unsigned long sock_ip;
+ int sock_port;
DEBUG_CALL("tcp_fconnect");
DEBUG_ARG("so = %lx", (long )so);
- sock_ip = so->so_faddr_ip;
- sock_port = so->so_faddr_port;
-
- if ((sock_ip & 0xffffff00) == special_addr_ip) {
- /* It's an alias */
- int last_byte = sock_ip & 0xff;
-
- if (CTL_IS_DNS(last_byte))
- sock_ip = dns_addr[last_byte - CTL_DNS];
- else
- sock_ip = loopback_addr_ip;
- try_proxy = 0;
- }
-
- sock_address_init_inet( &sockaddr, sock_ip, sock_port );
-
- DEBUG_MISC((dfd, " connect()ing, addr=%s, proxy=%d\n",
- sock_address_to_string(&sockaddr), try_proxy));
-
- if (try_proxy) {
- if (!proxy_manager_add(&sockaddr, SOCKET_STREAM, (ProxyEventFunc) tcp_proxy_event, so)) {
- soisfconnecting(so);
- so->s = -1;
- so->so_state |= SS_PROXIFIED;
- return 0;
- }
+ /* when true, a connection that otherwise would be dropped will instead be
+ * redirected to the sink ('-net-forward-tcp2sink') */
+ int forward_dropped_to_sink = 0;
+
+
+ /*-------------------------------------------------------------*/
+ /* User mode network stack restrictions */
+ if (slirp_should_drop(so->so_faddr_ip, so->so_faddr_port, IPPROTO_TCP)) {
+
+ /* If forwarding to sink is enabled, don't actually drop it */
+ if (slirp_should_forward_dropped_tcp2sink()) {
+ slirp_drop_log(
+ "About to be dropped TCP forwarded to sink: "
+ "src: 0x%08lx:0x%04x dst: 0x%08lx:0x%04x\n",
+ so->so_laddr_ip,
+ so->so_laddr_port,
+ so->so_faddr_ip,
+ so->so_faddr_port
+ );
+ forward_dropped_to_sink = 1;
+ }
+ else {
+ slirp_drop_log(
+ "Dropped TCP: src: 0x%08lx:0x%04x dst: 0x%08lx:0x%04x\n",
+ so->so_laddr_ip,
+ so->so_laddr_port,
+ so->so_faddr_ip,
+ so->so_faddr_port
+ );
+ //errno = ENETUNREACH;
+ errno = ECONNREFUSED;
+ return -1;
+ }
+ } else {
+ slirp_drop_log(
+ "Allowed TCP: src: 0x%08lx:0x%04x dst: 0x%08lx:0x%04x\n",
+ so->so_laddr_ip,
+ so->so_laddr_port,
+ so->so_faddr_ip,
+ so->so_faddr_port
+ );
}
+ /*-------------------------------------------------------------*/
if ((ret=so->s=socket_create_inet(SOCKET_STREAM)) >= 0)
{
@@ -434,6 +472,79 @@ int tcp_fconnect(struct socket *so)
socket_set_xreuseaddr(s);
socket_set_oobinline(s);
+
+ if (forward_dropped_to_sink) {
+
+ /* This connection would normally be dropped, but since forwarding of
+ * dropped connections is enabled, redirect it to the sink */
+ sock_ip = slirp_get_tcp_sink_ip();
+ sock_port= slirp_get_tcp_sink_port();
+ slirp_drop_log(
+ "Redirected would-be dropped TCP to sink: "
+ "src: 0x%08lx:0x%04x org dst: 0x%08lx:0x%04x "
+ "new dst: 0x%08lx:0x%04x\n",
+ so->so_laddr_ip, so->so_laddr_port,
+ so->so_faddr_ip, so->so_faddr_port,
+ sock_ip, sock_port
+ );
+ }
+ else { /* An allowed connection */
+
+ unsigned long faddr;
+ int fport;
+
+ /* Determine if the connection should be redirected
+ * due to a -net-forward rule */
+ /* faddr and fport are modified only on success */
+ if (slirp_should_net_forward(so->so_faddr_ip, so->so_faddr_port,
+ &faddr, &fport)) {
+ slirp_drop_log(
+ "Redirected TCP: src: 0x%08lx:0x%04x org dst: 0x%08lx:0x%04x "
+ "new dst: 0x%08lx:0x%04x\n",
+ so->so_laddr_ip, so->so_laddr_port,
+ so->so_faddr_ip, so->so_faddr_port,
+ faddr, fport
+ );
+ sock_ip = faddr; /* forced dst addr */
+ sock_port= fport; /* forced dst port */
+ }
+ /* Determine if this is a connection to a special qemu service,
+ * and change the destination address accordingly.
+ * 'faddr' is modified only onsuccess */
+ else if (is_qemu_special_address(so->so_faddr_ip, &faddr)) {
+
+ /* We keep the original destination port. If a special service
+ * listens on a different port than the standard, then appropriate
+ * forwarding should be set up using -net-forward, e.g., as it is
+ * the case with Mawler's DNS traffic, which is redirected to the
+ * special DNS port:
+ * -net-forward 0.0.0.0:0.0.0.0:53:127.0.0.1:21737 */
+
+ sock_ip = faddr; /* real DNS/gateway addr */
+ sock_port= so->so_faddr_port;/* original dst port */
+
+ }
+ /* A normal connection - keep the original destination addr/port */
+ else {
+
+ if (!proxy_manager_add(&sockaddr, SOCKET_STREAM,
+ (ProxyEventFunc) tcp_proxy_event, so)) {
+ soisfconnecting(so);
+ so->s = -1;
+ so->so_state |= SS_PROXIFIED;
+ return 0;
+ }
+
+ sock_ip = so->so_faddr_ip; /* original dst addr */
+ sock_port= so->so_faddr_port; /* original dst port */
+ }
+ }
+
+ DEBUG_MISC((dfd, " connect()ing, addr=%s, proxy=%d\n",
+ sock_address_to_string(&sockaddr), try_proxy));
+
+ sock_address_init_inet( &sockaddr, sock_ip, sock_port );
+
/* We don't care what port we get */
socket_connect(s, &sockaddr);
generated by cgit v1.1 at 2024-12-23 13:47:36 +0000