X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/49b23c5a9b0198bb382dcf43c458d46fcf2fa809..9f957a5883cb4c5c99cefa71b42fc9d2d27d73e1:/print-egp.c

diff --git a/print-egp.c b/print-egp.c
index 8e7bc335..b4a5a970 100644
--- a/print-egp.c
+++ b/print-egp.c
@@ -20,10 +20,14 @@
 
 /* \summary: Exterior Gateway Protocol (EGP) printer */
 
+/* specification: RFC 827 */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
+#include <string.h>
+
 #include <netdissect-stdinc.h>
 
 #include "netdissect.h"
@@ -31,15 +35,15 @@
 #include "extract.h"
 
 struct egp_packet {
-	uint8_t  egp_version;
+	nd_uint8_t  egp_version;
 #define	EGP_VERSION	2
-	uint8_t  egp_type;
+	nd_uint8_t  egp_type;
 #define  EGPT_ACQUIRE	3
 #define  EGPT_REACH	5
 #define  EGPT_POLL	2
 #define  EGPT_UPDATE	1
 #define  EGPT_ERROR	8
-	uint8_t  egp_code;
+	nd_uint8_t  egp_code;
 #define  EGPC_REQUEST	0
 #define  EGPC_CONFIRM	1
 #define  EGPC_REFUSE	2
@@ -47,7 +51,7 @@ struct egp_packet {
 #define  EGPC_CEASEACK	4
 #define  EGPC_HELLO	0
 #define  EGPC_HEARDU	1
-	uint8_t  egp_status;
+	nd_uint8_t  egp_status;
 #define  EGPS_UNSPEC	0
 #define  EGPS_ACTIVE	1
 #define  EGPS_PASSIVE	2
@@ -60,13 +64,13 @@ struct egp_packet {
 #define  EGPS_UP	1
 #define  EGPS_DOWN	2
 #define  EGPS_UNSOL	0x80
-	uint16_t  egp_checksum;
-	uint16_t  egp_as;
-	uint16_t  egp_sequence;
+	nd_uint16_t  egp_checksum;
+	nd_uint16_t  egp_as;
+	nd_uint16_t  egp_sequence;
 	union {
-		uint16_t  egpu_hello;
-		uint8_t egpu_gws[2];
-		uint16_t  egpu_reason;
+		nd_uint16_t egpu_hello;
+		nd_uint8_t  egpu_gws[2];
+		nd_uint16_t egpu_reason;
 #define  EGPR_UNSPEC	0
 #define  EGPR_BADHEAD	1
 #define  EGPR_BADDATA	2
@@ -80,8 +84,8 @@ struct egp_packet {
 #define  egp_extgw  egp_handg.egpu_gws[1]
 #define  egp_reason  egp_handg.egpu_reason
 	union {
-		uint16_t  egpu_poll;
-		uint32_t egpu_sourcenet;
+		nd_uint16_t egpu_poll;
+		nd_ipv4 egpu_sourcenet;
 	} egp_pands;
 #define  egp_poll  egp_pands.egpu_poll
 #define  egp_sourcenet  egp_pands.egpu_sourcenet
@@ -129,17 +133,17 @@ static const char *egp_reasons[] = {
 
 static void
 egpnrprint(netdissect_options *ndo,
-           register const struct egp_packet *egp)
+           const struct egp_packet *egp, u_int length)
 {
-	register const uint8_t *cp;
+	const uint8_t *cp;
 	uint32_t addr;
-	register uint32_t net;
-	register u_int netlen;
-	int gateways, distances, networks;
-	int t_gateways;
+	uint32_t net;
+	u_int netlen;
+	u_int gateways, distances, networks;
+	u_int intgw, extgw, t_gateways;
 	const char *comma;
 
-	addr = egp->egp_sourcenet;
+	addr = EXTRACT_IPV4_TO_NETWORK_ORDER(egp->egp_sourcenet);
 	if (IN_CLASSA(addr)) {
 		net = addr & IN_CLASSA_NET;
 		netlen = 1;
@@ -154,51 +158,85 @@ egpnrprint(netdissect_options *ndo,
 		netlen = 0;
 	}
 	cp = (const uint8_t *)(egp + 1);
+	length -= sizeof(*egp);
 
-	t_gateways = egp->egp_intgw + egp->egp_extgw;
+	intgw = EXTRACT_U_1(egp->egp_intgw);
+	extgw = EXTRACT_U_1(egp->egp_extgw);
+	t_gateways = intgw + extgw;
 	for (gateways = 0; gateways < t_gateways; ++gateways) {
 		/* Pickup host part of gateway address */
 		addr = 0;
-		ND_TCHECK2(cp[0], 4 - netlen);
+		if (length < 4 - netlen)
+			goto trunc;
+		ND_TCHECK_LEN(cp, 4 - netlen);
 		switch (netlen) {
 
 		case 1:
-			addr = *cp++;
+			addr = EXTRACT_U_1(cp);
+			cp++;
 			/* fall through */
 		case 2:
-			addr = (addr << 8) | *cp++;
+			addr = (addr << 8) | EXTRACT_U_1(cp);
+			cp++;
 			/* fall through */
 		case 3:
-			addr = (addr << 8) | *cp++;
+			addr = (addr << 8) | EXTRACT_U_1(cp);
+			cp++;
+			break;
 		}
 		addr |= net;
-		ND_TCHECK2(cp[0], 1);
-		distances = *cp++;
+		length -= 4 - netlen;
+		if (length < 1)
+			goto trunc;
+		ND_TCHECK_1(cp);
+		distances = EXTRACT_U_1(cp);
+		cp++;
+		length--;
 		ND_PRINT((ndo, " %s %s ",
-		       gateways < (int)egp->egp_intgw ? "int" : "ext",
+		       gateways < intgw ? "int" : "ext",
 		       ipaddr_string(ndo, &addr)));
 
 		comma = "";
 		ND_PRINT((ndo, "("));
-		while (--distances >= 0) {
-			ND_TCHECK2(cp[0], 2);
-			ND_PRINT((ndo, "%sd%d:", comma, (int)*cp++));
+		while (distances != 0) {
+			if (length < 2)
+				goto trunc;
+			ND_TCHECK_2(cp);
+			ND_PRINT((ndo, "%sd%u:", comma, EXTRACT_U_1(cp)));
+			cp++;
 			comma = ", ";
-			networks = *cp++;
-			while (--networks >= 0) {
+			networks = EXTRACT_U_1(cp);
+			cp++;
+			length -= 2;
+			while (networks != 0) {
 				/* Pickup network number */
-				ND_TCHECK2(cp[0], 1);
-				addr = (uint32_t)*cp++ << 24;
+				if (length < 1)
+					goto trunc;
+				ND_TCHECK_1(cp);
+				addr = ((uint32_t) EXTRACT_U_1(cp)) << 24;
+				cp++;
+				length--;
 				if (IN_CLASSB(addr)) {
-					ND_TCHECK2(cp[0], 1);
-					addr |= (uint32_t)*cp++ << 16;
+					if (length < 1)
+						goto trunc;
+					ND_TCHECK_1(cp);
+					addr |= ((uint32_t) EXTRACT_U_1(cp)) << 16;
+					cp++;
+					length--;
 				} else if (!IN_CLASSA(addr)) {
-					ND_TCHECK2(cp[0], 2);
-					addr |= (uint32_t)*cp++ << 16;
-					addr |= (uint32_t)*cp++ << 8;
+					if (length < 2)
+						goto trunc;
+					ND_TCHECK_2(cp);
+					addr |= ((uint32_t) EXTRACT_U_1(cp)) << 16;
+					cp++;
+					addr |= ((uint32_t) EXTRACT_U_1(cp)) << 8;
+					cp++;
+					length -= 2;
 				}
 				ND_PRINT((ndo, " %s", ipaddr_string(ndo, &addr)));
+				networks--;
 			}
+			distances--;
 		}
 		ND_PRINT((ndo, ")"));
 	}
@@ -209,39 +247,41 @@ trunc:
 
 void
 egp_print(netdissect_options *ndo,
-          register const uint8_t *bp, register u_int length)
+          const uint8_t *bp, u_int length)
 {
-	register const struct egp_packet *egp;
-	register int status;
-	register int code;
-	register int type;
+	const struct egp_packet *egp;
+	u_int version;
+	u_int type;
+	u_int code;
+	u_int status;
 
 	egp = (const struct egp_packet *)bp;
-        if (!ND_TTEST2(*egp, length)) {
+	if (length < sizeof(*egp) || !ND_TTEST(*egp)) {
 		ND_PRINT((ndo, "[|egp]"));
 		return;
 	}
 
+	version = EXTRACT_U_1(egp->egp_version);
         if (!ndo->ndo_vflag) {
             ND_PRINT((ndo, "EGPv%u, AS %u, seq %u, length %u",
-                   egp->egp_version,
-                   EXTRACT_16BITS(&egp->egp_as),
-                   EXTRACT_16BITS(&egp->egp_sequence),
+                   version,
+                   EXTRACT_BE_U_2(egp->egp_as),
+                   EXTRACT_BE_U_2(egp->egp_sequence),
                    length));
             return;
         } else
             ND_PRINT((ndo, "EGPv%u, length %u",
-                   egp->egp_version,
+                   version,
                    length));
 
-	if (egp->egp_version != EGP_VERSION) {
-		ND_PRINT((ndo, "[version %d]", egp->egp_version));
+	if (version != EGP_VERSION) {
+		ND_PRINT((ndo, "[version %u]", version));
 		return;
 	}
 
-	type = egp->egp_type;
-	code = egp->egp_code;
-	status = egp->egp_status;
+	type = EXTRACT_U_1(egp->egp_type);
+	code = EXTRACT_U_1(egp->egp_code);
+	status = EXTRACT_U_1(egp->egp_status);
 
 	switch (type) {
 	case EGPT_ACQUIRE:
@@ -258,12 +298,12 @@ egp_print(netdissect_options *ndo,
 				break;
 
 			default:
-				ND_PRINT((ndo, " [status %d]", status));
+				ND_PRINT((ndo, " [status %u]", status));
 				break;
 			}
-			ND_PRINT((ndo, " hello:%d poll:%d",
-			       EXTRACT_16BITS(&egp->egp_hello),
-			       EXTRACT_16BITS(&egp->egp_poll)));
+			ND_PRINT((ndo, " hello:%u poll:%u",
+			       EXTRACT_BE_U_2(egp->egp_hello),
+			       EXTRACT_BE_U_2(egp->egp_poll)));
 			break;
 
 		case EGPC_REFUSE:
@@ -281,13 +321,13 @@ egp_print(netdissect_options *ndo,
 				break;
 
 			default:
-				ND_PRINT((ndo, "[status %d]", status));
+				ND_PRINT((ndo, "[status %u]", status));
 				break;
 			}
 			break;
 
 		default:
-			ND_PRINT((ndo, "[code %d]", code));
+			ND_PRINT((ndo, "[code %u]", code));
 			break;
 		}
 		break;
@@ -301,21 +341,21 @@ egp_print(netdissect_options *ndo,
 			if (status <= EGPS_DOWN)
 				ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 			else
-				ND_PRINT((ndo, " [status %d]", status));
+				ND_PRINT((ndo, " [status %u]", status));
 			break;
 
 		default:
-			ND_PRINT((ndo, "[reach code %d]", code));
+			ND_PRINT((ndo, "[reach code %u]", code));
 			break;
 		}
 		break;
 
 	case EGPT_POLL:
 		ND_PRINT((ndo, " poll"));
-		if (egp->egp_status <= EGPS_DOWN)
+		if (status <= EGPS_DOWN)
 			ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 		else
-			ND_PRINT((ndo, " [status %d]", status));
+			ND_PRINT((ndo, " [status %u]", status));
 		ND_PRINT((ndo, " net:%s", ipaddr_string(ndo, &egp->egp_sourcenet)));
 		break;
 
@@ -328,13 +368,13 @@ egp_print(netdissect_options *ndo,
 		if (status <= EGPS_DOWN)
 			ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 		else
-			ND_PRINT((ndo, " [status %d]", status));
-		ND_PRINT((ndo, " %s int %d ext %d",
+			ND_PRINT((ndo, " [status %u]", status));
+		ND_PRINT((ndo, " %s int %u ext %u",
 		       ipaddr_string(ndo, &egp->egp_sourcenet),
-		       egp->egp_intgw,
-		       egp->egp_extgw));
+		       EXTRACT_U_1(egp->egp_intgw),
+		       EXTRACT_U_1(egp->egp_extgw)));
 		if (ndo->ndo_vflag)
-			egpnrprint(ndo, egp);
+			egpnrprint(ndo, egp, length);
 		break;
 
 	case EGPT_ERROR:
@@ -342,16 +382,16 @@ egp_print(netdissect_options *ndo,
 		if (status <= EGPS_DOWN)
 			ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 		else
-			ND_PRINT((ndo, " [status %d]", status));
+			ND_PRINT((ndo, " [status %u]", status));
 
-		if (EXTRACT_16BITS(&egp->egp_reason) <= EGPR_UVERSION)
-			ND_PRINT((ndo, " %s", egp_reasons[EXTRACT_16BITS(&egp->egp_reason)]));
+		if (EXTRACT_BE_U_2(egp->egp_reason) <= EGPR_UVERSION)
+			ND_PRINT((ndo, " %s", egp_reasons[EXTRACT_BE_U_2(egp->egp_reason)]));
 		else
-			ND_PRINT((ndo, " [reason %d]", EXTRACT_16BITS(&egp->egp_reason)));
+			ND_PRINT((ndo, " [reason %u]", EXTRACT_BE_U_2(egp->egp_reason)));
 		break;
 
 	default:
-		ND_PRINT((ndo, "[type %d]", type));
+		ND_PRINT((ndo, "[type %u]", type));
 		break;
 	}
 }