From: Guus Sliepen <guus@tinc-vpn.org>
Date: Thu, 30 Aug 2012 12:21:23 +0000 (+0200)
Subject: Properly handle SPTPS packets with stripped Ethernet headers.
X-Git-Tag: release-1.1pre3~56
X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=commitdiff_plain;h=742f7bb04e72d93f2c4a858534144a599b3fc14d

Properly handle SPTPS packets with stripped Ethernet headers.
---

diff --git a/src/net_packet.c b/src/net_packet.c
index 69199a72..ac63f628 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -643,6 +643,14 @@ bool receive_sptps_record(void *handle, uint8_t type, const char *data, uint16_t
 		return false;
 	}
 
+	/* Check if we have the headers we need */
+	if(routing_mode != RMODE_ROUTER && !(type & PKT_MAC)) {
+		logger(DEBUG_TRAFFIC, LOG_ERR, "Received packet from %s (%s) without MAC header (maybe Mode is not set correctly)", from->name, from->hostname);
+		return false;
+	} else if(routing_mode == RMODE_ROUTER && (type & PKT_MAC)) {
+		logger(DEBUG_TRAFFIC, LOG_WARNING, "Received packet from %s (%s) with MAC header (maybe Mode is not set correctly)", from->name, from->hostname);
+	}
+
 	int offset = (type & PKT_MAC) ? 0 : 14;
 	if(type & PKT_COMPRESSED) {
 		len = uncompress_packet(inpkt.data + offset, (const uint8_t *)data, len, from->incompression);
@@ -658,6 +666,25 @@ bool receive_sptps_record(void *handle, uint8_t type, const char *data, uint16_t
 		inpkt.len = len + offset;
 	}
 
+	/* Generate the Ethernet packet type if necessary */
+	if(offset) {
+		switch(inpkt.data[14] >> 4) {
+			case 4:
+				inpkt.data[12] = 0x08;
+				inpkt.data[13] = 0x00;
+				break;
+			case 6:
+				inpkt.data[12] = 0x86;
+				inpkt.data[13] = 0xDD;
+				break;
+			default:
+				logger(DEBUG_TRAFFIC, LOG_ERR,
+						   "Unknown IP version %d while reading packet from %s (%s)",
+						   inpkt.data[14] >> 4, from->name, from->hostname);
+				return false;
+		}
+	}
+
 	receive_packet(from, &inpkt);
 	return true;
 }