X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fmeta.c;h=ccc3b2e670d5ae9a0210929d804703323f97983f;hp=a56f46187ac9f30687aaa4b71af82ad0285b1a19;hb=5c5ae8c48e0414cb4831ccfd2b147ab65bb5fd5c;hpb=4c85542894f7fca823b119b05e07179deb24229a

diff --git a/src/meta.c b/src/meta.c
index a56f4618..ccc3b2e6 100644
--- a/src/meta.c
+++ b/src/meta.c
@@ -1,7 +1,8 @@
 /*
     meta.c -- handle the meta communication
-    Copyright (C) 2000-2009 Guus Sliepen <guus@tinc-vpn.org>,
+    Copyright (C) 2000-2017 Guus Sliepen <guus@tinc-vpn.org>,
                   2000-2005 Ivo Timmermans
+                  2006      Scott Lamb <slamb@slamb.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -29,6 +30,7 @@
 #include "meta.h"
 #include "net.h"
 #include "protocol.h"
+#include "proxy.h"
 #include "utils.h"
 #include "xalloc.h"
 
@@ -60,6 +62,14 @@ bool send_meta(connection_t *c, const char *buffer, int length) {
 
 	/* Add our data to buffer */
 	if(c->status.encryptout) {
+		/* Check encryption limits */
+		if(length > c->outbudget) {
+			ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for encryption to %s (%s)", c->name, c->hostname);
+			return false;
+		} else {
+			c->outbudget -= length;
+		}
+
 		result = EVP_EncryptUpdate(c->outctx, (unsigned char *)c->outbuf + c->outbufstart + c->outbuflen,
 				&outlen, (unsigned char *)buffer, length);
 		if(!result || outlen < length) {
@@ -93,15 +103,13 @@ bool flush_meta(connection_t *c) {
 						   c->name, c->hostname);
 			} else if(errno == EINTR) {
 				continue;
-#ifdef EWOULDBLOCK
-			} else if(errno == EWOULDBLOCK) {
-				ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block",
+			} else if(sockwouldblock(sockerrno)) {
+				ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block",
 						c->outbuflen, c->name, c->hostname);
 				return true;
-#endif
 			} else {
 				logger(LOG_ERR, "Flushing meta data to %s (%s) failed: %s", c->name,
-					   c->hostname, strerror(errno));
+					   c->hostname, sockstrerror(sockerrno));
 			}
 
 			return false;
@@ -148,11 +156,11 @@ bool receive_meta(connection_t *c) {
 		if(!lenin || !errno) {
 			ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)",
 					   c->name, c->hostname);
-		} else if(errno == EINTR)
+		} else if(sockwouldblock(sockerrno))
 			return true;
 		else
 			logger(LOG_ERR, "Metadata socket read error for %s (%s): %s",
-				   c->name, c->hostname, strerror(errno));
+				   c->name, c->hostname, sockstrerror(sockerrno));
 
 		return false;
 	}
@@ -161,9 +169,28 @@ bool receive_meta(connection_t *c) {
 	c->buflen += lenin;
 
 	while(lenin > 0) {
+		reqlen = 0;
+
+		/* Is it proxy metadata? */
+
+		if(c->allow_request == PROXY) {
+			reqlen = receive_proxy_meta(c, oldlen, lenin);
+			if(reqlen < 0)
+				return false;
+			goto consume;
+		}
+
 		/* Decrypt */
 
 		if(c->status.decryptin && !decrypted) {
+			/* Check decryption limits */
+			if(lenin > c->inbudget) {
+				ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for decryption from %s (%s)", c->name, c->hostname);
+				return false;
+			} else {
+				c->inbudget -= lenin;
+			}
+
 			result = EVP_DecryptUpdate(c->inctx, (unsigned char *)inbuf, &lenout, (unsigned char *)c->buffer + oldlen, lenin);
 			if(!result || lenout != lenin) {
 				logger(LOG_ERR, "Error while decrypting metadata from %s (%s): %s",
@@ -178,36 +205,32 @@ bool receive_meta(connection_t *c) {
 
 		if(c->tcplen) {
 			if(c->tcplen <= c->buflen) {
-				receive_tcppacket(c, c->buffer, c->tcplen);
+				if(c->allow_request != ALL) {
+					logger(LOG_ERR, "Got unauthorized TCP packet from %s (%s)", c->name, c->hostname);
+					return false;
+				}
 
-				c->buflen -= c->tcplen;
-				lenin -= c->tcplen - oldlen;
-				memmove(c->buffer, c->buffer + c->tcplen, c->buflen);
-				oldlen = 0;
+				receive_tcppacket(c, c->buffer, c->tcplen);
+				reqlen = c->tcplen;
 				c->tcplen = 0;
-				continue;
-			} else {
-				break;
 			}
-		}
-
-		/* Otherwise we are waiting for a request */
-
-		reqlen = 0;
-
-		for(i = oldlen; i < c->buflen; i++) {
-			if(c->buffer[i] == '\n') {
-				c->buffer[i] = '\0';	/* replace end-of-line by end-of-string so we can use sscanf */
-				reqlen = i + 1;
-				break;
+		} else {
+			/* Otherwise we are waiting for a request */
+
+			for(i = oldlen; i < c->buflen; i++) {
+				if(c->buffer[i] == '\n') {
+					c->buffer[i] = '\0';	/* replace end-of-line by end-of-string so we can use sscanf */
+					c->reqlen = reqlen = i + 1;
+					break;
+				}
 			}
-		}
 
-		if(reqlen) {
-			c->reqlen = reqlen;
-			if(!receive_request(c))
+			if(reqlen && !receive_request(c))
 				return false;
+		}
 
+consume:
+		if(reqlen) {
 			c->buflen -= reqlen;
 			lenin -= reqlen - oldlen;
 			memmove(c->buffer, c->buffer + reqlen, c->buflen);
@@ -224,7 +247,5 @@ bool receive_meta(connection_t *c) {
 		return false;
 	}
 
-	c->last_ping_time = now;
-
 	return true;
 }