X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/57356d6317f6f33dd622711d305c4579df63b269..5ecd7ad009cc5148c67b9d665f79a64083fae254:/proxy.c

diff --git a/proxy.c b/proxy.c
index a02fc11c..0a61741e 100644
--- a/proxy.c
+++ b/proxy.c
@@ -14,6 +14,10 @@
 #include "network.h"
 #include "proxy.h"
 
+#define do_proxy_dns(cfg) \
+    (cfg->proxy_dns == FORCE_ON || \
+	 (cfg->proxy_dns == AUTO && cfg->proxy_type != PROXY_SOCKS))
+
 /*
  * Call this when proxy negotiation is complete, so that this
  * socket can begin working normally.
@@ -87,7 +91,7 @@ static void sk_proxy_close (Socket s)
     sfree(ps);
 }
 
-static int sk_proxy_write (Socket s, char *data, int len)
+static int sk_proxy_write (Socket s, const char *data, int len)
 {
     Proxy_Socket ps = (Proxy_Socket) s;
 
@@ -98,7 +102,7 @@ static int sk_proxy_write (Socket s, char *data, int len)
     return sk_write(ps->sub_socket, data, len);
 }
 
-static int sk_proxy_write_oob (Socket s, char *data, int len)
+static int sk_proxy_write_oob (Socket s, const char *data, int len)
 {
     Proxy_Socket ps = (Proxy_Socket) s;
 
@@ -240,20 +244,36 @@ static int plug_proxy_accepting (Plug p, void *sock)
     return plug_accepting(ps->plug, sock);
 }
 
-static int proxy_for_destination (SockAddr addr, char * hostname, int port)
+/*
+ * This function can accept a NULL pointer as `addr', in which case
+ * it will only check the host name.
+ */
+static int proxy_for_destination (SockAddr addr, char *hostname, int port,
+				  const Config *cfg)
 {
     int s = 0, e = 0;
     char hostip[64];
     int hostip_len, hostname_len;
-    char * exclude_list;
+    const char *exclude_list;
+
+    /*
+     * Check the host name and IP against the hard-coded
+     * representations of `localhost'.
+     */
+    if (!cfg->even_proxy_localhost &&
+	(sk_hostname_is_local(hostname) ||
+	 (addr && sk_address_is_local(addr))))
+	return 0;		       /* do not proxy */
 
     /* we want a string representation of the IP address for comparisons */
-    sk_getaddr(addr, hostip, 64);
+    if (addr) {
+	sk_getaddr(addr, hostip, 64);
+	hostip_len = strlen(hostip);
+    }
 
-    hostip_len = strlen(hostip);
     hostname_len = strlen(hostname);
 
-    exclude_list = cfg.proxy_exclude_list;
+    exclude_list = cfg->proxy_exclude_list;
 
     /* now parse the exclude list, and see if either our IP
      * or hostname matches anything in it.
@@ -277,8 +297,8 @@ static int proxy_for_destination (SockAddr addr, char * hostname, int port)
 	if (exclude_list[s] == '*') {
 	    /* wildcard at beginning of entry */
 
-	    if (strnicmp(hostip + hostip_len - (e - s - 1),
-			 exclude_list + s + 1, e - s - 1) == 0 ||
+	    if ((addr && strnicmp(hostip + hostip_len - (e - s - 1),
+				  exclude_list + s + 1, e - s - 1) == 0) ||
 		strnicmp(hostname + hostname_len - (e - s - 1),
 			 exclude_list + s + 1, e - s - 1) == 0)
 		return 0; /* IP/hostname range excluded. do not use proxy. */
@@ -286,7 +306,7 @@ static int proxy_for_destination (SockAddr addr, char * hostname, int port)
 	} else if (exclude_list[e-1] == '*') {
 	    /* wildcard at end of entry */
 
-	    if (strnicmp(hostip, exclude_list + s, e - s - 1) == 0 ||
+	    if ((addr && strnicmp(hostip, exclude_list + s, e - s - 1) == 0) ||
 		strnicmp(hostname, exclude_list + s, e - s - 1) == 0)
 		return 0; /* IP/hostname range excluded. do not use proxy. */
 
@@ -295,22 +315,41 @@ static int proxy_for_destination (SockAddr addr, char * hostname, int port)
 	     * match (ie. a specific IP)
 	     */
 
-	    if (stricmp(hostip, exclude_list + s) == 0)
+	    if (addr && stricmp(hostip, exclude_list + s) == 0)
 		return 0; /* IP/hostname excluded. do not use proxy. */
 	    if (stricmp(hostname, exclude_list + s) == 0)
 		return 0; /* IP/hostname excluded. do not use proxy. */
 	}
 
 	s = e;
+
+	/* Make sure we really have reached the next comma or end-of-string */
+	while (exclude_list[s] &&
+	       !isspace(exclude_list[s]) &&
+	       exclude_list[s] != ',') s++;
     }
 
     /* no matches in the exclude list, so use the proxy */
     return 1;
 }
 
+SockAddr name_lookup(char *host, int port, char **canonicalname,
+		     const Config *cfg)
+{
+    if (cfg->proxy_type != PROXY_NONE &&
+	do_proxy_dns(cfg) &&
+	proxy_for_destination(NULL, host, port, cfg)) {
+	*canonicalname = dupstr(host);
+	return sk_nonamelookup(host);
+    }
+
+    return sk_namelookup(host, canonicalname);
+}
+
 Socket new_connection(SockAddr addr, char *hostname,
 		      int port, int privport,
-		      int oobinline, int nodelay, Plug plug)
+		      int oobinline, int nodelay, Plug plug,
+		      const Config *cfg)
 {
     static const struct socket_function_table socket_fn_table = {
 	sk_proxy_plug,
@@ -331,16 +370,17 @@ Socket new_connection(SockAddr addr, char *hostname,
 	plug_proxy_accepting
     };
 
-    if (cfg.proxy_type != PROXY_NONE &&
-	proxy_for_destination(addr, hostname, port))
+    if (cfg->proxy_type != PROXY_NONE &&
+	proxy_for_destination(addr, hostname, port, cfg))
     {
 	Proxy_Socket ret;
 	Proxy_Plug pplug;
 	SockAddr proxy_addr;
-	char * proxy_canonical_name;
+	char *proxy_canonical_name, *err;
 
 	ret = smalloc(sizeof(struct Socket_proxy_tag));
 	ret->fn = &socket_fn_table;
+	ret->cfg = *cfg;	       /* STRUCTURE COPY */
 	ret->plug = plug;
 	ret->remote_addr = addr;
 	ret->remote_port = port;
@@ -357,14 +397,14 @@ Socket new_connection(SockAddr addr, char *hostname,
 	ret->state = PROXY_STATE_NEW;
 	ret->negotiate = NULL;
 	
-	if (cfg.proxy_type == PROXY_HTTP) {
+	if (cfg->proxy_type == PROXY_HTTP) {
 	    ret->negotiate = proxy_http_negotiate;
-	} else if (cfg.proxy_type == PROXY_SOCKS) {
-	    if (cfg.proxy_socks_version == 4)
+	} else if (cfg->proxy_type == PROXY_SOCKS) {
+	    if (cfg->proxy_socks_version == 4)
 		ret->negotiate = proxy_socks4_negotiate;
 	    else
 		ret->negotiate = proxy_socks5_negotiate;
-	} else if (cfg.proxy_type == PROXY_TELNET) {
+	} else if (cfg->proxy_type == PROXY_TELNET) {
 	    ret->negotiate = proxy_telnet_negotiate;
 	} else {
 	    ret->error = "Proxy error: Unknown proxy method";
@@ -378,14 +418,18 @@ Socket new_connection(SockAddr addr, char *hostname,
 	pplug->proxy_socket = ret;
 
 	/* look-up proxy */
-	proxy_addr = sk_namelookup(cfg.proxy_host,
+	proxy_addr = sk_namelookup(cfg->proxy_host,
 				   &proxy_canonical_name);
+	if ((err = sk_addr_error(proxy_addr)) != NULL) {
+	    ret->error = "Proxy error: Unable to resolve proxy host name";
+	    return (Socket)ret;
+	}
 	sfree(proxy_canonical_name);
 
 	/* create the actual socket we will be using,
 	 * connected to our proxy server and port.
 	 */
-	ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port,
+	ret->sub_socket = sk_new(proxy_addr, cfg->proxy_port,
 				 privport, oobinline,
 				 nodelay, (Plug) pplug);
 	if (sk_socket_error(ret->sub_socket) != NULL)
@@ -404,13 +448,14 @@ Socket new_connection(SockAddr addr, char *hostname,
     return sk_new(addr, port, privport, oobinline, nodelay, plug);
 }
 
-Socket new_listener(int port, Plug plug, int local_host_only)
+Socket new_listener(char *srcaddr, int port, Plug plug, int local_host_only,
+		    const Config *cfg)
 {
     /* TODO: SOCKS (and potentially others) support inbound
      * TODO: connections via the proxy. support them.
      */
 
-    return sk_newlistener(port, plug, local_host_only);
+    return sk_newlistener(srcaddr, port, plug, local_host_only);
 }
 
 /* ----------------------------------------------------------------------
@@ -459,30 +504,30 @@ int proxy_http_negotiate (Proxy_Socket p, int change)
 	 * for this proxy method, it's just a simple HTTP
 	 * request
 	 */
-	char *buf, dest[64];
+	char *buf, dest[512];
 
-	sk_getaddr(p->remote_addr, dest, 64);
+	sk_getaddr(p->remote_addr, dest, lenof(dest));
 
 	buf = dupprintf("CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n",
 			dest, p->remote_port, dest, p->remote_port);
 	sk_write(p->sub_socket, buf, strlen(buf));
 	sfree(buf);
 
-	if (cfg.proxy_username[0] || cfg.proxy_password[0]) {
-	    char buf[sizeof(cfg.proxy_username)+sizeof(cfg.proxy_password)];
+	if (p->cfg.proxy_username[0] || p->cfg.proxy_password[0]) {
+	    char buf[sizeof(p->cfg.proxy_username)+sizeof(p->cfg.proxy_password)];
 	    char buf2[sizeof(buf)*4/3 + 100];
 	    int i, j, len;
-	    sprintf(buf, "%s:%s", cfg.proxy_username, cfg.proxy_password);
+	    sprintf(buf, "%s:%s", p->cfg.proxy_username, p->cfg.proxy_password);
 	    len = strlen(buf);
 	    sprintf(buf2, "Proxy-Authorization: basic ");
 	    for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4)
-		base64_encode_atom(buf+i, (len-i > 3 ? 3 : len-i), buf2+j);
+		base64_encode_atom((unsigned char *)(buf+i),
+				   (len-i > 3 ? 3 : len-i), buf2+j);
 	    strcpy(buf2+j, "\r\n");
 	    sk_write(p->sub_socket, buf2, strlen(buf2));
 	}
 
-	sprintf(buf, "\r\n");
-	sk_write(p->sub_socket, buf, strlen(buf));
+	sk_write(p->sub_socket, "\r\n", 2);
 
 	p->state = 1;
 	return 0;
@@ -595,6 +640,7 @@ int proxy_http_negotiate (Proxy_Socket p, int change)
 	    {
 		bufchain_consume(&p->pending_input_data, eol);
 		datap += eol;
+		len   -= eol;
 		eol = get_line_end(datap, len);
 	    }
 
@@ -637,18 +683,27 @@ int proxy_socks4_negotiate (Proxy_Socket p, int change)
 	 *  user ID (variable length, null terminated string)
 	 */
 
-	int length;
-	char * command;
+	int length, type, namelen;
+	char *command, addr[4], hostname[512];
 
-	if (sk_addrtype(p->remote_addr) != ADDRTYPE_IPV4) {
+	type = sk_addrtype(p->remote_addr);
+	if (type == ADDRTYPE_IPV6) {
 	    plug_closing(p->plug, "Proxy error: SOCKS version 4 does"
 			 " not support IPv6", PROXY_ERROR_GENERAL, 0);
 	    return 1;
+	} else if (type == ADDRTYPE_IPV4) {
+	    namelen = 0;
+	    sk_addrcopy(p->remote_addr, addr);
+	} else {		       /* type == ADDRTYPE_NAME */
+	    sk_getaddr(p->remote_addr, hostname, lenof(hostname));
+	    namelen = strlen(hostname) + 1;   /* include the NUL */
+	    addr[0] = addr[1] = addr[2] = 0;
+	    addr[3] = 1;
 	}
 
-	length = strlen(cfg.proxy_username) + 9;
+	length = strlen(p->cfg.proxy_username) + namelen + 9;
 	command = (char*) smalloc(length);
-	strcpy(command + 8, cfg.proxy_username);
+	strcpy(command + 8, p->cfg.proxy_username);
 
 	command[0] = 4; /* version 4 */
 	command[1] = 1; /* CONNECT command */
@@ -658,7 +713,11 @@ int proxy_socks4_negotiate (Proxy_Socket p, int change)
 	command[3] = (char) p->remote_port & 0xff;
 
 	/* address */
-	sk_addrcopy(p->remote_addr, command + 4);
+	memcpy(command + 4, addr, 4);
+
+	/* hostname */
+	memcpy(command + 8 + strlen(p->cfg.proxy_username) + 1,
+	       hostname, namelen);
 
 	sk_write(p->sub_socket, command, length);
 	sfree(command);
@@ -785,7 +844,7 @@ int proxy_socks5_negotiate (Proxy_Socket p, int change)
 	int len;
 
 	command[0] = 5; /* version 5 */
-	if (cfg.proxy_username[0] || cfg.proxy_password[0]) {
+	if (p->cfg.proxy_username[0] || p->cfg.proxy_password[0]) {
 	    command[1] = 2;	       /* two methods supported: */
 	    command[2] = 0x00;	       /* no authentication */
 	    command[3] = 0x02;	       /* username/password */
@@ -927,24 +986,30 @@ int proxy_socks5_negotiate (Proxy_Socket p, int change)
 	     *  dest. port (2 bytes) [network order]
 	     */
 
-	    char command[22];
+	    char command[512];
 	    int len;
+	    int type;
 
-	    if (sk_addrtype(p->remote_addr) == ADDRTYPE_IPV6) {
-		len = 10;
+	    type = sk_addrtype(p->remote_addr);
+	    if (type == ADDRTYPE_IPV4) {
+		len = 10;	       /* 4 hdr + 4 addr + 2 trailer */
 		command[3] = 1; /* IPv4 */
-	    } else {
-		len = 22;
+		sk_addrcopy(p->remote_addr, command+4);
+	    } else if (type == ADDRTYPE_IPV6) {
+		len = 22;	       /* 4 hdr + 16 addr + 2 trailer */
 		command[3] = 4; /* IPv6 */
+		sk_addrcopy(p->remote_addr, command+4);
+	    } else if (type == ADDRTYPE_NAME) {
+		command[3] = 3;
+		sk_getaddr(p->remote_addr, command+5, 256);
+		command[4] = strlen(command+5);
+		len = 7 + command[4];  /* 4 hdr, 1 len, N addr, 2 trailer */
 	    }
 
 	    command[0] = 5; /* version 5 */
 	    command[1] = 1; /* CONNECT command */
 	    command[2] = 0x00;
 
-	    /* address */
-	    sk_addrcopy(p->remote_addr, command+4);
-
 	    /* port */
 	    command[len-2] = (char) (p->remote_port >> 8) & 0xff;
 	    command[len-1] = (char) p->remote_port & 0xff;
@@ -1048,18 +1113,18 @@ int proxy_socks5_negotiate (Proxy_Socket p, int change)
 	}
 
 	if (p->state == 5) {
-	    if (cfg.proxy_username[0] || cfg.proxy_password[0]) {
+	    if (p->cfg.proxy_username[0] || p->cfg.proxy_password[0]) {
 		char userpwbuf[514];
 		int ulen, plen;
-		ulen = strlen(cfg.proxy_username);
+		ulen = strlen(p->cfg.proxy_username);
 		if (ulen > 255) ulen = 255; if (ulen < 1) ulen = 1;
-		plen = strlen(cfg.proxy_password);
+		plen = strlen(p->cfg.proxy_password);
 		if (plen > 255) plen = 255; if (plen < 1) plen = 1;
 		userpwbuf[0] = 1;      /* version number of subnegotiation */
 		userpwbuf[1] = ulen;
-		memcpy(userpwbuf+2, cfg.proxy_username, ulen);
+		memcpy(userpwbuf+2, p->cfg.proxy_username, ulen);
 		userpwbuf[ulen+2] = plen;
-		memcpy(userpwbuf+ulen+3, cfg.proxy_password, plen);
+		memcpy(userpwbuf+ulen+3, p->cfg.proxy_password, plen);
 		sk_write(p->sub_socket, userpwbuf, ulen + plen + 3);
 		p->state = 7;
 	    } else 
@@ -1103,37 +1168,37 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
 	 * %%, %host, %port, %user, and %pass
 	 */
 
-	while (cfg.proxy_telnet_command[eo] != 0) {
+	while (p->cfg.proxy_telnet_command[eo] != 0) {
 
 	    /* scan forward until we hit end-of-line, 
 	     * or an escape character (\ or %) */
-	    while (cfg.proxy_telnet_command[eo] != 0 &&
-		   cfg.proxy_telnet_command[eo] != '%' &&
-		   cfg.proxy_telnet_command[eo] != '\\') eo++;
+	    while (p->cfg.proxy_telnet_command[eo] != 0 &&
+		   p->cfg.proxy_telnet_command[eo] != '%' &&
+		   p->cfg.proxy_telnet_command[eo] != '\\') eo++;
 
 	    /* if we hit eol, break out of our escaping loop */
-	    if (cfg.proxy_telnet_command[eo] == 0) break;
+	    if (p->cfg.proxy_telnet_command[eo] == 0) break;
 
 	    /* if there was any unescaped text before the escape
 	     * character, send that now */
 	    if (eo != so) {
 		sk_write(p->sub_socket, 
-			 cfg.proxy_telnet_command + so, eo - so);
+			 p->cfg.proxy_telnet_command + so, eo - so);
 	    }
 
 	    so = eo++;
 
 	    /* if the escape character was the last character of
 	     * the line, we'll just stop and send it. */
-	    if (cfg.proxy_telnet_command[eo] == 0) break;
+	    if (p->cfg.proxy_telnet_command[eo] == 0) break;
 
-	    if (cfg.proxy_telnet_command[so] == '\\') {
+	    if (p->cfg.proxy_telnet_command[so] == '\\') {
 
 		/* we recognize \\, \%, \r, \n, \t, \x??. 
 		 * anything else, we just send unescaped (including the \). 
 		 */
 
-		switch (cfg.proxy_telnet_command[eo]) {
+		switch (p->cfg.proxy_telnet_command[eo]) {
 
 		  case '\\':
 		    sk_write(p->sub_socket, "\\", 1);
@@ -1169,15 +1234,15 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
 
 		    for (;;) {
 			eo++;
-			if (cfg.proxy_telnet_command[eo] >= '0' &&
-			    cfg.proxy_telnet_command[eo] <= '9')
-			    v += cfg.proxy_telnet_command[eo] - '0';
-			else if (cfg.proxy_telnet_command[eo] >= 'a' &&
-				 cfg.proxy_telnet_command[eo] <= 'f')
-			    v += cfg.proxy_telnet_command[eo] - 'a' + 10;
-			else if (cfg.proxy_telnet_command[eo] >= 'A' &&
-				 cfg.proxy_telnet_command[eo] <= 'F')
-			    v += cfg.proxy_telnet_command[eo] - 'A' + 10;
+			if (p->cfg.proxy_telnet_command[eo] >= '0' &&
+			    p->cfg.proxy_telnet_command[eo] <= '9')
+			    v += p->cfg.proxy_telnet_command[eo] - '0';
+			else if (p->cfg.proxy_telnet_command[eo] >= 'a' &&
+				 p->cfg.proxy_telnet_command[eo] <= 'f')
+			    v += p->cfg.proxy_telnet_command[eo] - 'a' + 10;
+			else if (p->cfg.proxy_telnet_command[eo] >= 'A' &&
+				 p->cfg.proxy_telnet_command[eo] <= 'F')
+			    v += p->cfg.proxy_telnet_command[eo] - 'A' + 10;
 			else {
 			    /* non hex character, so we abort and just
 			     * send the whole thing unescaped (including \x)
@@ -1189,7 +1254,7 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
 
 			/* we only extract two hex characters */
 			if (i == 1) {
-			    sk_write(p->sub_socket, &v, 1);
+			    sk_write(p->sub_socket, (char *)&v, 1);
 			    eo++;
 			    break;
 			}
@@ -1202,7 +1267,7 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
 
 		  default:
 		    sk_write(p->sub_socket, 
-			     cfg.proxy_telnet_command + so, 2);
+			     p->cfg.proxy_telnet_command + so, 2);
 		    eo++;
 		    break;
 		}
@@ -1212,34 +1277,34 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
 		 * anything else, we just send unescaped (including the %). 
 		 */
 
-		if (cfg.proxy_telnet_command[eo] == '%') {
+		if (p->cfg.proxy_telnet_command[eo] == '%') {
 		    sk_write(p->sub_socket, "%", 1);
 		    eo++;
 		}
-		else if (strnicmp(cfg.proxy_telnet_command + eo,
+		else if (strnicmp(p->cfg.proxy_telnet_command + eo,
 				  "host", 4) == 0) {
-		    char dest[64];
-		    sk_getaddr(p->remote_addr, dest, 64);
+		    char dest[512];
+		    sk_getaddr(p->remote_addr, dest, lenof(dest));
 		    sk_write(p->sub_socket, dest, strlen(dest));
 		    eo += 4;
 		}
-		else if (strnicmp(cfg.proxy_telnet_command + eo,
+		else if (strnicmp(p->cfg.proxy_telnet_command + eo,
 				  "port", 4) == 0) {
 		    char port[8];
 		    sprintf(port, "%i", p->remote_port);
 		    sk_write(p->sub_socket, port, strlen(port));
 		    eo += 4;
 		}
-		else if (strnicmp(cfg.proxy_telnet_command + eo,
+		else if (strnicmp(p->cfg.proxy_telnet_command + eo,
 				  "user", 4) == 0) {
-		    sk_write(p->sub_socket, cfg.proxy_username, 
-			strlen(cfg.proxy_username));
+		    sk_write(p->sub_socket, p->cfg.proxy_username, 
+			strlen(p->cfg.proxy_username));
 		    eo += 4;
 		}
-		else if (strnicmp(cfg.proxy_telnet_command + eo,
+		else if (strnicmp(p->cfg.proxy_telnet_command + eo,
 				  "pass", 4) == 0) {
-		    sk_write(p->sub_socket, cfg.proxy_password, 
-			strlen(cfg.proxy_password));
+		    sk_write(p->sub_socket, p->cfg.proxy_password, 
+			strlen(p->cfg.proxy_password));
 		    eo += 4;
 		}
 		else {
@@ -1257,7 +1322,7 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
 
 	/* if there is any unescaped text at the end of the line, send it */
 	if (eo != so) {
-	    sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so);
+	    sk_write(p->sub_socket, p->cfg.proxy_telnet_command + so, eo - so);
 	}
 
 	p->state = 1;