From: guy <guy>
Date: Fri, 6 May 2005 07:57:17 +0000 (+0000)
Subject: Add an "fn_printzp()" routine for printing null-padded strings (strings
X-Git-Tag: tcpdump-3.9.1~62
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/01fe0ebe27b2fe957f699ffa4dbdedc46e12f85b

Add an "fn_printzp()" routine for printing null-padded strings (strings
with a maximum length, where a string shorter than that length is padded
with NULs), as "fn_print()" won't handle the maximum length *and* the
snapshot length and "fn_printn()" won't stop on a null string.  Use it
where appropriate.

Always pass "snapend" to "fn_print()" and "fn_printn()" if they're
passed a pointer into the packet data; only pass NULL if they're being
handed a pointer into a buffer that's not part of the packet data.

Always check the return value of "fn_print()", "fn_printn()", and
"fn_printzp()" if they're passed "snapend", and do the appropriate
string termination and "packet truncated" indication if they return 1.
---

diff --git a/interface.h b/interface.h
index ca8701fc..f85e4412 100644
--- a/interface.h
+++ b/interface.h
@@ -18,7 +18,7 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Header: /tcpdump/master/tcpdump/interface.h,v 1.244.2.5 2005-05-03 20:39:25 hannes Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/tcpdump/interface.h,v 1.244.2.6 2005-05-06 07:57:17 guy Exp $ (LBL)
  */
 
 #ifndef tcpdump_interface_h
@@ -137,6 +137,7 @@ extern void relts_print(int);
 
 extern int fn_print(const u_char *, const u_char *);
 extern int fn_printn(const u_char *, u_int, const u_char *);
+extern int fn_printzp(const u_char *, u_int, const u_char *);
 extern int mask2plen(u_int32_t);
 extern const char *tok2strary_internal(const char **, int, const char *, int);
 #define	tok2strary(a,f,i) tok2strary_internal(a, sizeof(a)/sizeof(a[0]),f,i)
diff --git a/print-hsrp.c b/print-hsrp.c
index fe49538e..21ec0540 100644
--- a/print-hsrp.c
+++ b/print-hsrp.c
@@ -31,7 +31,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-hsrp.c,v 1.9 2003-11-16 09:36:22 guy Exp $";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-hsrp.c,v 1.9.2.1 2005-05-06 07:57:17 guy Exp $";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -127,7 +127,11 @@ hsrp_print(register const u_int8_t *bp, register u_int len)
 		relts_print(hp->hsrp_holdtime);
 		printf(" priority=%d", hp->hsrp_priority);
 		printf(" auth=\"");
-		fn_printn(hp->hsrp_authdata, sizeof(hp->hsrp_authdata), NULL);
+		if (fn_printn(hp->hsrp_authdata, sizeof(hp->hsrp_authdata),
+		    snapend)) {
+			printf("\"");
+			goto trunc;
+		}
 		printf("\"");
 	}
 	return;
diff --git a/print-ipx.c b/print-ipx.c
index b5f6de6d..77fbcb67 100644
--- a/print-ipx.c
+++ b/print-ipx.c
@@ -24,7 +24,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ipx.c,v 1.40 2004-05-26 19:57:57 guy Exp $";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ipx.c,v 1.40.2.1 2005-05-06 07:57:18 guy Exp $";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -161,7 +161,10 @@ ipx_sap_print(const u_short *ipx, u_int length)
 	for (i = 0; i < 8 && length > 0; i++) {
 	    TCHECK2(ipx[25], 10);
 	    (void)printf(" %s '", ipxsap_string(htons(EXTRACT_16BITS(&ipx[0]))));
-	    fn_print((u_char *)&ipx[1], (u_char *)&ipx[1] + 48);
+	    if (fn_printzp((u_char *)&ipx[1], 48, snapend)) {
+		printf("'");
+		goto trunc;
+	    }
 	    printf("' addr %s",
 		ipxaddr_string(EXTRACT_32BITS(&ipx[25]), (u_char *)&ipx[27]));
 	    ipx += 32;
diff --git a/print-nfs.c b/print-nfs.c
index d74f43ff..7502823e 100644
--- a/print-nfs.c
+++ b/print-nfs.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-nfs.c,v 1.106.2.1 2005-04-20 21:52:31 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-nfs.c,v 1.106.2.2 2005-05-06 07:57:18 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -388,9 +388,11 @@ parsefn(register const u_int32_t *dp)
 	cp = (u_char *)dp;
 	/* Update 32-bit pointer (NFS filenames padded to 32-bit boundaries) */
 	dp += ((len + 3) & ~3) / sizeof(*dp);
-	/* XXX seems like we should be checking the length */
 	putchar('"');
-	(void) fn_printn(cp, len, NULL);
+	if (fn_printn(cp, len, snapend)) {
+		putchar('"');
+		goto trunc;
+	}
 	putchar('"');
 
 	return (dp);
diff --git a/print-ntp.c b/print-ntp.c
index f9b65b25..b408e087 100644
--- a/print-ntp.c
+++ b/print-ntp.c
@@ -25,7 +25,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.41 2004-01-28 14:54:50 hannes Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.41.2.1 2005-05-06 07:57:18 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -133,7 +133,8 @@ ntp_print(register const u_char *cp, u_int length)
 		break;
 
 	case PRIM_REF:
-		fn_printn((u_char *)&(bp->refid), 4, NULL);
+		if (fn_printn((u_char *)&(bp->refid), 4, snapend))
+			goto trunc;
 		break;
 
 	case INFO_QUERY:
diff --git a/print-ospf.c b/print-ospf.c
index f9cff38b..60cb6eb9 100644
--- a/print-ospf.c
+++ b/print-ospf.c
@@ -23,7 +23,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ospf.c,v 1.56.2.1 2005-04-20 21:55:32 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ospf.c,v 1.56.2.2 2005-05-06 07:57:19 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -932,8 +932,11 @@ ospf_print(register const u_char *bp, register u_int length,
 			break;
 
 		case OSPF_AUTH_SIMPLE:
-			(void)fn_printn(op->ospf_authdata,
-			    sizeof(op->ospf_authdata), NULL);
+			if (fn_printn(op->ospf_authdata,
+			    sizeof(op->ospf_authdata), snapend)) {
+				printf("\"");
+				goto trunc;
+			}
 			printf("\"");
 			break;
 
diff --git a/print-snmp.c b/print-snmp.c
index 387a9d5a..15e440f5 100644
--- a/print-snmp.c
+++ b/print-snmp.c
@@ -58,7 +58,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-snmp.c,v 1.62.2.1 2005-04-18 00:08:02 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-snmp.c,v 1.62.2.2 2005-05-06 07:57:19 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -786,7 +786,10 @@ asn1_print(struct be *elem)
 		p = elem->data.str;
 		if (printable) {
 			putchar('"');
-			(void)fn_print(p, p + asnlen);
+			if (fn_printn(p, asnlen, snapend)) {
+				putchar('"');
+				goto trunc;
+			}
 			putchar('"');
 		} else
 			for (i = asnlen; i-- > 0; p++) {
diff --git a/print-vrrp.c b/print-vrrp.c
index 12fbe7b3..12e47716 100644
--- a/print-vrrp.c
+++ b/print-vrrp.c
@@ -25,7 +25,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-vrrp.c,v 1.9 2003-11-16 09:36:41 guy Exp $";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-vrrp.c,v 1.9.2.1 2005-05-06 07:57:20 guy Exp $";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -128,7 +128,10 @@ vrrp_print(register const u_char *bp, register u_int len, int ttl)
 		if (auth_type == VRRP_AUTH_SIMPLE) { /* simple text password */
 			TCHECK(bp[7]);
 			printf(" auth \"");
-			fn_printn(bp, 8, NULL);
+			if (fn_printn(bp, 8, snapend)) {
+				printf("\"");
+				goto trunc;
+			}
 			printf("\"");
 		}
 	}
diff --git a/util.c b/util.c
index 27b36f49..f6443051 100644
--- a/util.c
+++ b/util.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/util.c,v 1.95.2.2 2005-04-26 03:44:36 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/util.c,v 1.95.2.3 2005-05-06 07:57:20 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -45,7 +45,7 @@ static const char rcsid[] _U_ =
 #include "interface.h"
 
 /*
- * Print out a filename (or other ascii string).
+ * Print out a null-terminated filename (or other ascii string).
  * If ep is NULL, assume no truncation check is needed.
  * Return true if truncated.
  */
@@ -104,6 +104,40 @@ fn_printn(register const u_char *s, register u_int n,
 	return (n == 0) ? 0 : 1;
 }
 
+/*
+ * Print out a null-padded filename (or other ascii string).
+ * If ep is NULL, assume no truncation check is needed.
+ * Return true if truncated.
+ */
+int
+fn_printzp(register const u_char *s, register u_int n,
+	  register const u_char *ep)
+{
+	register int ret;
+	register u_char c;
+
+	ret = 1;			/* assume truncated */
+	while (n > 0 && (ep == NULL || s < ep)) {
+		n--;
+		c = *s++;
+		if (c == '\0') {
+			ret = 0;
+			break;
+		}
+		if (!isascii(c)) {
+			c = toascii(c);
+			putchar('M');
+			putchar('-');
+		}
+		if (!isprint(c)) {
+			c ^= 0x40;	/* DEL to ?, others to alpha */
+			putchar('^');
+		}
+		putchar(c);
+	}
+	return (n == 0) ? 0 : 1;
+}
+
 /*
  * Print the timestamp
  */