Adjust default_print() to not run over snapend.

Kill default_print_unaligned() and adjust default_print() to also work
with unaligned buffers. There is no need for two functions doing the
same thing.

Pass the right length in nsh_print to default_print(). Fixes on place
that makes tcpdump crash.
Reported by Peter J. Philipp (pjp at delphinusdns dot org)
OK mbuhl@

diff --git a/usr.sbin/tcpdump/interface.h b/usr.sbin/tcpdump/interface.h
index 602be40..4e055f3 100644 (file)
--- a/usr.sbin/tcpdump/interface.h
+++ b/usr.sbin/tcpdump/interface.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: interface.h,v 1.86 2020/08/17 06:29:29 dlg Exp $      */
+/*     $OpenBSD: interface.h,v 1.87 2023/02/28 10:04:50 claudio Exp $  */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
@@ -20,7 +20,7 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Id: interface.h,v 1.86 2020/08/17 06:29:29 dlg Exp $ (LBL)
+ * @(#) $Id: interface.h,v 1.87 2023/02/28 10:04:50 claudio Exp $ (LBL)
  */
 
 #ifndef tcpdump_interface_h
@@ -199,7 +199,6 @@ extern void bootp_print(const u_char *, u_int, u_short, u_short);
 extern void bgp_print(const u_char *, int);
 extern void decnet_print(const u_char *, u_int, u_int);
 extern void default_print(const u_char *, u_int);
-extern void default_print_unaligned(const u_char *, u_int);
 extern void dvmrp_print(const u_char *, u_int);
 extern void egp_print(const u_char *, u_int, const u_char *);
 extern void enc_if_print(u_char *, const struct pcap_pkthdr *, const u_char *);

diff --git a/usr.sbin/tcpdump/print-isoclns.c b/usr.sbin/tcpdump/print-isoclns.c
index 0c94a02..ea2edac 100644 (file)
--- a/usr.sbin/tcpdump/print-isoclns.c
+++ b/usr.sbin/tcpdump/print-isoclns.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: print-isoclns.c,v 1.15 2021/12/01 18:28:46 deraadt Exp $      */
+/*     $OpenBSD: print-isoclns.c,v 1.16 2023/02/28 10:04:50 claudio Exp $      */
 
 /*
  * Copyright (c) 1992, 1993, 1994, 1995, 1996
@@ -88,7 +88,7 @@ isoclns_print(const u_char *p, u_int length, u_int caplen,
                /* isis_print(&p, &length); */
                printf(" len=%d ", length);
                if (caplen > 1)
-                       default_print_unaligned(p, caplen);
+                       default_print(p, caplen);
                break;
 
        case NULLNS:
@@ -107,7 +107,7 @@ isoclns_print(const u_char *p, u_int length, u_int caplen,
                            etheraddr_string(edst));
                printf(" len=%d ", length);
                if (caplen > 1)
-                       default_print_unaligned(p, caplen);
+                       default_print(p, caplen);
                break;
        }
 }

diff --git a/usr.sbin/tcpdump/print-llc.c b/usr.sbin/tcpdump/print-llc.c
index 1482968..ed48dc4 100644 (file)
--- a/usr.sbin/tcpdump/print-llc.c
+++ b/usr.sbin/tcpdump/print-llc.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: print-llc.c,v 1.22 2020/01/24 22:46:37 procter Exp $  */
+/*     $OpenBSD: print-llc.c,v 1.23 2023/02/28 10:04:50 claudio Exp $  */
 
 /*
  * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
@@ -219,7 +219,7 @@ llc_print(const u_char *p, u_int length, u_int caplen,
                printf("%s/%c", m, f);
 
                if (caplen < 6) {
-                       default_print_unaligned(p, caplen);
+                       default_print(p, caplen);
                        return (0);
                }
                p += 3;
@@ -248,7 +248,7 @@ llc_print(const u_char *p, u_int length, u_int caplen,
        } else {
                char f;
                if (caplen < 4) {
-                       default_print_unaligned(p, caplen);
+                       default_print(p, caplen);
                        return (0);
                }
                llc.llcis = ntohs(llc.llcis);

diff --git a/usr.sbin/tcpdump/print-nsh.c b/usr.sbin/tcpdump/print-nsh.c
index f21fe69..9d66bf1 100644 (file)
--- a/usr.sbin/tcpdump/print-nsh.c
+++ b/usr.sbin/tcpdump/print-nsh.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: print-nsh.c,v 1.1 2019/12/03 01:43:33 dlg Exp $ */
+/*     $OpenBSD: print-nsh.c,v 1.2 2023/02/28 10:04:50 claudio Exp $ */
 
 /*
  * Copyright (c) 2019 David Gwynne <dlg@openbsd.org>
@@ -214,7 +214,7 @@ nsh_print(const u_char *p, u_int length)
        }
 
        if (vflag)
-               default_print_unaligned(p, length);
+               default_print(p, l);
 
        return;
 trunc:

diff --git a/usr.sbin/tcpdump/tcpdump.c b/usr.sbin/tcpdump/tcpdump.c
index fccccd4..336f4ef 100644 (file)
--- a/usr.sbin/tcpdump/tcpdump.c
+++ b/usr.sbin/tcpdump/tcpdump.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: tcpdump.c,v 1.97 2022/07/09 23:24:44 halex Exp $      */
+/*     $OpenBSD: tcpdump.c,v 1.98 2023/02/28 10:04:50 claudio Exp $    */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
@@ -632,44 +632,15 @@ default_print_ascii(const u_char *cp, unsigned int length)
        }
 }
 
-/* Like default_print() but data need not be aligned */
-void
-default_print_unaligned(const u_char *cp, u_int length)
-{
-       u_int i, s;
-       int nshorts;
-
-       if (Xflag) {
-               /* dump the buffer in `emacs-hexl' style */
-               default_print_hexl(cp, length);
-       } else if (Aflag) {
-               /* dump the text in the buffer */
-               default_print_ascii(cp, length);
-       } else {
-               /* dump the buffer in old tcpdump style */
-               nshorts = (u_int) length / sizeof(u_short);
-               i = 0;
-               while (--nshorts >= 0) {
-                       if ((i++ % 8) == 0)
-                               printf("\n\t\t\t");
-                       s = *cp++;
-                       printf(" %02x%02x", s, *cp++);
-               }
-               if (length & 1) {
-                       if ((i % 8) == 0)
-                               printf("\n\t\t\t");
-                       printf(" %02x", *cp);
-               }
-       }
-}
-
 void
 default_print(const u_char *bp, u_int length)
 {
-       const u_short *sp;
        u_int i;
        int nshorts;
 
+       if (snapend - bp < length)
+               length = snapend - bp;
+
        if (Xflag) {
                /* dump the buffer in `emacs-hexl' style */
                default_print_hexl(bp, length);
@@ -677,23 +648,23 @@ default_print(const u_char *bp, u_int length)
                /* dump the text in the buffer */
                default_print_ascii(bp, length);
        } else {
+               u_short sp;
+
                /* dump the buffer in old tcpdump style */
-               if ((long)bp & 1) {
-                       default_print_unaligned(bp, length);
-                       return;
-               }
-               sp = (u_short *)bp;
                nshorts = (u_int) length / sizeof(u_short);
                i = 0;
                while (--nshorts >= 0) {
                        if ((i++ % 8) == 0)
                                printf("\n\t\t\t");
-                       printf(" %04x", ntohs(*sp++));
+
+                       sp = (u_short)*bp++ << 8;
+                       sp |= *bp++;
+                       printf(" %04x", sp);
                }
                if (length & 1) {
                        if ((i % 8) == 0)
                                printf("\n\t\t\t");
-                       printf(" %02x", *(u_char *)sp);
+                       printf(" %02x", *bp);
                }
        }
 }