diff options
Diffstat (limited to 'contrib/tcpdump/print-dtp.c')
| -rw-r--r-- | contrib/tcpdump/print-dtp.c | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/contrib/tcpdump/print-dtp.c b/contrib/tcpdump/print-dtp.c index 5d84a77..1d8c66a 100644 --- a/contrib/tcpdump/print-dtp.c +++ b/contrib/tcpdump/print-dtp.c @@ -12,22 +12,23 @@ * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE. * - * Dynamic Trunk Protocol (DTP) - * * Original code by Carles Kishimoto <carles.kishimoto@gmail.com> */ -#define NETDISSECT_REWORKED +/* \summary: Dynamic Trunking Protocol (DTP) printer */ + #ifdef HAVE_CONFIG_H #include "config.h" #endif -#include <tcpdump-stdinc.h> +#include <netdissect-stdinc.h> -#include "interface.h" +#include "netdissect.h" #include "addrtoname.h" #include "extract.h" +static const char tstr[] = " [|dtp]"; + #define DTP_HEADER_LEN 1 #define DTP_DOMAIN_TLV 0x0001 #define DTP_STATUS_TLV 0x0002 @@ -71,30 +72,36 @@ dtp_print (netdissect_options *ndo, const u_char *pptr, u_int length) while (tptr < (pptr+length)) { ND_TCHECK2(*tptr, 4); - type = EXTRACT_16BITS(tptr); len = EXTRACT_16BITS(tptr+2); - - /* infinite loop check */ - if (type == 0 || len == 0) { + /* XXX: should not be but sometimes it is, see the test captures */ + if (type == 0) return; - } - ND_PRINT((ndo, "\n\t%s (0x%04x) TLV, length %u", tok2str(dtp_tlv_values, "Unknown", type), type, len)); + /* infinite loop check */ + if (len < 4) + goto invalid; + ND_TCHECK2(*tptr, len); + switch (type) { case DTP_DOMAIN_TLV: - ND_PRINT((ndo, ", %s", tptr+4)); + ND_PRINT((ndo, ", ")); + fn_printzp(ndo, tptr+4, len-4, pptr+length); break; case DTP_STATUS_TLV: case DTP_DTP_TYPE_TLV: + if (len < 5) + goto invalid; ND_PRINT((ndo, ", 0x%x", *(tptr+4))); break; case DTP_NEIGHBOR_TLV: + if (len < 10) + goto invalid; ND_PRINT((ndo, ", %s", etheraddr_string(ndo, tptr+4))); break; @@ -106,8 +113,11 @@ dtp_print (netdissect_options *ndo, const u_char *pptr, u_int length) return; + invalid: + ND_PRINT((ndo, "%s", istr)); + return; trunc: - ND_PRINT((ndo, "[|dtp]")); + ND_PRINT((ndo, "%s", tstr)); } /* |
