From 1c082acf77e6256d9e47a3c9490b7615d591e67b Mon Sep 17 00:00:00 2001
From: =?utf8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Date: Fri, 1 Jan 2021 16:33:23 +0100
Subject: [PATCH] pppoe: Show verbose information about all concentrator when
 pppoe-verbose option is set
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
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Signed-off-by: Pali Rohár <pali@kernel.org>
---
 pppd/plugins/pppoe/discovery.c | 69 +++++++++++++++++++++++++++-------
 1 file changed, 55 insertions(+), 14 deletions(-)

diff --git a/pppd/plugins/pppoe/discovery.c b/pppd/plugins/pppoe/discovery.c
index 1d3d12b..86ea207 100644
--- a/pppd/plugins/pppoe/discovery.c
+++ b/pppd/plugins/pppoe/discovery.c
@@ -148,26 +148,56 @@ parsePADOTags(UINT16_t type, UINT16_t len, unsigned char *data,
 	break;
     case TAG_SERVICE_NAME:
 	pc->seenServiceName = 1;
+	if (pppoe_verbose >= 1 && len > 0) {
+	    info("Service-Name: %.*s", (int) len, data);
+	}
 	if (conn->serviceName && len == strlen(conn->serviceName) &&
 	    !strncmp((char *) data, conn->serviceName, len)) {
 	    pc->serviceNameOK = 1;
 	}
 	break;
     case TAG_AC_COOKIE:
-	conn->cookie.type = htons(type);
-	conn->cookie.length = htons(len);
-	memcpy(conn->cookie.payload, data, len);
+	if (pppoe_verbose >= 1) {
+	    char buffer[100];
+	    char *ptr = buffer;
+	    ptr += sprintf(ptr, "Cookie:");
+	    /* Print first 20 bytes of cookie */
+	    for (i=0; i<len && i < 20; i++) {
+		ptr += sprintf(ptr, " %02x", (unsigned) data[i]);
+	    }
+	    if (i < len) ptr += sprintf(ptr, "...");
+	    info(buffer);
+	}
+	if (conn->discoveryState != STATE_RECEIVED_PADO) {
+	    conn->cookie.type = htons(type);
+	    conn->cookie.length = htons(len);
+	    memcpy(conn->cookie.payload, data, len);
+	}
 	break;
     case TAG_RELAY_SESSION_ID:
-	conn->relayId.type = htons(type);
-	conn->relayId.length = htons(len);
-	memcpy(conn->relayId.payload, data, len);
+	if (pppoe_verbose >= 1) {
+	    char buffer[100];
+	    char *ptr = buffer;
+	    ptr += sprintf(ptr, "Relay-ID:");
+	    /* Print first 20 bytes of relay ID */
+	    for (i=0; i<len && i < 20; i++) {
+		ptr += printf(ptr, " %02x", (unsigned) data[i]);
+	    }
+	    if (i < len) ptr += printf(ptr, "...");
+	    info(buffer);
+	}
+	if (conn->discoveryState != STATE_RECEIVED_PADO) {
+	    conn->relayId.type = htons(type);
+	    conn->relayId.length = htons(len);
+	    memcpy(conn->relayId.payload, data, len);
+	}
 	break;
     case TAG_PPP_MAX_PAYLOAD:
 	if (len == sizeof(mru)) {
 	    memcpy(&mru, data, sizeof(mru));
 	    mru = ntohs(mru);
-	    if (mru >= ETH_PPPOE_MTU) {
+	    info("Max-Payload: %u", (unsigned) mru);
+	    if (mru >= ETH_PPPOE_MTU && conn->discoveryState != STATE_RECEIVED_PADO) {
 		if (conn->mtu > mru)
 		    conn->mtu = mru;
 		if (conn->mru > mru)
@@ -211,7 +241,9 @@ parsePADSTags(UINT16_t type, UINT16_t len, unsigned char *data,
     UINT16_t mru;
     switch(type) {
     case TAG_SERVICE_NAME:
-	dbglog("PADS: Service-Name: '%.*s'", (int) len, data);
+	if (pppoe_verbose >= 1 && len > 0) {
+	    info("PADS: Service-Name: '%.*s'", (int) len, data);
+	}
 	break;
     case TAG_PPP_MAX_PAYLOAD:
 	if (len == sizeof(mru)) {
@@ -351,7 +383,6 @@ waitForPADO(PPPoEConnection *conn, int timeout)
     pc.seenACName    = 0;
     pc.seenServiceName = 0;
     conn->seenMaxPayload = 0;
-    conn->error = 0;
 
     if (get_time(&expire_at) < 0) {
 	error("get_time (waitForPADO): %m");
@@ -379,6 +410,7 @@ waitForPADO(PPPoEConnection *conn, int timeout)
 		return;		/* Timed out */
 	}
 
+	conn->error = 0;
 	/* Get the packet */
 	receivePacket(conn->discoverySocket, &packet, &len);
 
@@ -408,9 +440,9 @@ waitForPADO(PPPoEConnection *conn, int timeout)
 		continue;
 	    }
 	    if (parsePacket(&packet, parsePADOTags, &pc) < 0)
-		return;
+		continue;
 	    if (conn->error)
-		return;
+		continue;
 	    if (!pc.seenACName) {
 		error("Ignoring PADO packet with no AC-Name tag");
 		continue;
@@ -419,14 +451,23 @@ waitForPADO(PPPoEConnection *conn, int timeout)
 		error("Ignoring PADO packet with no Service-Name tag");
 		continue;
 	    }
+	    if (pppoe_verbose >= 1) {
+		info("AC-Ethernet-Address: %02x:%02x:%02x:%02x:%02x:%02x",
+		       (unsigned) packet.ethHdr.h_source[0],
+		       (unsigned) packet.ethHdr.h_source[1],
+		       (unsigned) packet.ethHdr.h_source[2],
+		       (unsigned) packet.ethHdr.h_source[3],
+		       (unsigned) packet.ethHdr.h_source[4],
+		       (unsigned) packet.ethHdr.h_source[5]);
+		info("--------------------------------------------------");
+	    }
 	    conn->numPADOs++;
-	    if (pc.acNameOK && pc.serviceNameOK) {
+	    if (pc.acNameOK && pc.serviceNameOK && conn->discoveryState != STATE_RECEIVED_PADO) {
 		memcpy(conn->peerEth, packet.ethHdr.h_source, ETH_ALEN);
 		conn->discoveryState = STATE_RECEIVED_PADO;
-		break;
 	    }
 	}
-    } while (conn->discoveryState != STATE_RECEIVED_PADO);
+    } while (pppoe_verbose >= 1 || conn->discoveryState != STATE_RECEIVED_PADO);
 }
 
 /***********************************************************************
-- 
2.39.2