From 5d490c4106f4a34864c980b925e183cf3bf575e2 Mon Sep 17 00:00:00 2001
From: Paul Mackerras <paulus@samba.org>
Date: Tue, 13 Jan 2004 04:03:58 +0000
Subject: [PATCH] PPPoE updates: don't exit if discovery fails, cope with both
 protocol field compression and no compression, recognize nasXXX and tapXXX as
 devices over which we can do PPPoE. Patches sent by Marco d'Itri.

---
 pppd/plugins/rp-pppoe/common.c    | 41 ++++++++++++++++++++++---------
 pppd/plugins/rp-pppoe/discovery.c |  8 +++---
 pppd/plugins/rp-pppoe/plugin.c    | 12 +++++----
 3 files changed, 42 insertions(+), 19 deletions(-)

diff --git a/pppd/plugins/rp-pppoe/common.c b/pppd/plugins/rp-pppoe/common.c
index a285b48..a39e97a 100644
--- a/pppd/plugins/rp-pppoe/common.c
+++ b/pppd/plugins/rp-pppoe/common.c
@@ -14,7 +14,7 @@
 ***********************************************************************/
 
 static char const RCSID[] =
-"$Id: common.c,v 1.1 2001/12/14 02:55:20 mostrows Exp $";
+"$Id: common.c,v 1.2 2004/01/13 04:03:58 paulus Exp $";
 
 #include "pppoe.h"
 
@@ -178,6 +178,7 @@ strDup(char const *str)
     return copy;
 }
 
+#ifdef PPPOE_STANDALONE
 /**********************************************************************
 *%FUNCTION: computeTCPChecksum
 *%ARGUMENTS:
@@ -248,21 +249,38 @@ clampMSS(PPPoEPacket *packet, char const *dir, int clampMss)
     unsigned char *mssopt = NULL;
     UINT16_t csum;
 
-    int len;
+    int len, minlen;
 
-    /* Is it IPv4? */
-    if (packet->payload[0] != 0x00 ||
-	packet->payload[1] != 0x21) {
-	/* Nope, ignore it */
-	return;
-    }
+    /* check PPP protocol type */
+    if (packet->payload[0] & 0x01) {
+        /* 8 bit protocol type */
 
-    ipHdr = packet->payload + 2;
+        /* Is it IPv4? */
+        if (packet->payload[0] != 0x21) {
+            /* Nope, ignore it */
+            return;
+        }
+
+        ipHdr = packet->payload + 1;
+	minlen = 41;
+    } else {
+        /* 16 bit protocol type */
+
+        /* Is it IPv4? */
+        if (packet->payload[0] != 0x00 ||
+            packet->payload[1] != 0x21) {
+            /* Nope, ignore it */
+            return;
+        }
+
+        ipHdr = packet->payload + 2;
+	minlen = 42;
+    }
 
     /* Is it too short? */
     len = (int) ntohs(packet->length);
-    if (len < 42) {
-	/* 20 byte IP header; 20 byte TCP header; 2 byte PPP protocol */
+    if (len < minlen) {
+	/* 20 byte IP header; 20 byte TCP header; at least 1 or 2 byte PPP protocol */
 	return;
     }
 
@@ -362,6 +380,7 @@ clampMSS(PPPoEPacket *packet, char const *dir, int clampMss)
     csum = computeTCPChecksum(ipHdr, tcpHdr);
     (* (UINT16_t *) (tcpHdr+16)) = csum;
 }
+#endif /* PPPOE_STANDALONE */
 
 /***********************************************************************
 *%FUNCTION: sendPADT
diff --git a/pppd/plugins/rp-pppoe/discovery.c b/pppd/plugins/rp-pppoe/discovery.c
index d2c3a89..e05b773 100644
--- a/pppd/plugins/rp-pppoe/discovery.c
+++ b/pppd/plugins/rp-pppoe/discovery.c
@@ -9,7 +9,7 @@
 ***********************************************************************/
 
 static char const RCSID[] =
-"$Id: discovery.c,v 1.1 2001/12/14 02:55:20 mostrows Exp $";
+"$Id: discovery.c,v 1.2 2004/01/13 04:03:58 paulus Exp $";
 
 #include "pppoe.h"
 
@@ -602,7 +602,8 @@ discovery(PPPoEConnection *conn)
     do {
 	padiAttempts++;
 	if (padiAttempts > MAX_PADI_ATTEMPTS) {
-	    rp_fatal("Timeout waiting for PADO packets");
+	    warn("Timeout waiting for PADO packets");
+	    return;
 	}
 	sendPADI(conn);
 	conn->discoveryState = STATE_SENT_PADI;
@@ -629,7 +630,8 @@ discovery(PPPoEConnection *conn)
     do {
 	padrAttempts++;
 	if (padrAttempts > MAX_PADI_ATTEMPTS) {
-	    rp_fatal("Timeout waiting for PADS packets");
+	    warn("Timeout waiting for PADS packets");
+	    return;
 	}
 	sendPADR(conn);
 	conn->discoveryState = STATE_SENT_PADR;
diff --git a/pppd/plugins/rp-pppoe/plugin.c b/pppd/plugins/rp-pppoe/plugin.c
index 0ef4344..00316ae 100644
--- a/pppd/plugins/rp-pppoe/plugin.c
+++ b/pppd/plugins/rp-pppoe/plugin.c
@@ -22,7 +22,7 @@
 ***********************************************************************/
 
 static char const RCSID[] =
-"$Id: plugin.c,v 1.9 2003/04/07 00:01:46 paulus Exp $";
+"$Id: plugin.c,v 1.10 2004/01/13 04:03:58 paulus Exp $";
 
 #define _GNU_SOURCE 1
 #include "pppoe.h"
@@ -144,7 +144,8 @@ PPPOEConnectDevice(void)
     } else {
 	discovery(conn);
 	if (conn->discoveryState != STATE_SESSION) {
-	    fatal("Unable to complete PPPoE Discovery");
+	    error("Unable to complete PPPoE Discovery");
+	    return -1;
 	}
     }
 
@@ -276,13 +277,14 @@ PPPoEDevnameHook(char *cmd, char **argv, int doit)
     int fd;
     struct ifreq ifr;
 
-    /* Only do it if name is "ethXXX" or "nic-XXXX.  In latter case,
-       strip off the "nic-" */
+    /* Only do it if name is "ethXXX", "nasXXX", "tapXXX" or "nic-XXXX.
+       In latter case strip off the "nic-" */
     /* Thanks to Russ Couturier for this fix */
     if (strlen(cmd) > 4 && !strncmp(cmd, "nic-", 4)) {
 	/* Strip off "nic-" */
 	cmd += 4;
-    } else if (strlen(cmd) < 4 || strncmp(cmd, "eth", 3)) {
+    } else if (strlen(cmd) < 4 || (strncmp(cmd, "eth", 3) &&
+		strncmp(cmd, "nas", 3) && strncmp(cmd, "tap", 3))) {
 	if (OldDevnameHook) return OldDevnameHook(cmd, argv, doit);
 	return 0;
     }
-- 
2.39.2