From f2f366e7158657c4b0525a4361f9beba98bb6b27 Mon Sep 17 00:00:00 2001 From: Guy Harris Date: Tue, 13 Oct 1998 07:48:03 +0000 Subject: On most systems, bit-swap the bytes of an FDDI MAC address. (List of systems on which you don't bit-swap them taken from "tcpdump"; the list may not be complete.) svn path=/trunk/; revision=48 --- packet-fddi.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 67 insertions(+), 8 deletions(-) (limited to 'packet-fddi.c') diff --git a/packet-fddi.c b/packet-fddi.c index 45f3256b1e..51ad3df218 100644 --- a/packet-fddi.c +++ b/packet-fddi.c @@ -3,7 +3,7 @@ * * Laurent Deniel * - * $Id: packet-fddi.c,v 1.4 1998/10/13 05:55:45 guy Exp $ + * $Id: packet-fddi.c,v 1.5 1998/10/13 07:48:03 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs @@ -74,22 +74,83 @@ #define FDDI_P_DHOST 1 #define FDDI_P_SHOST 7 -void dissect_fddi(const u_char *pd, frame_data *fd, GtkTree *tree) +/* On some systems, the FDDI MAC addresses are bit-swapped. */ +#if !defined(ultrix) && !defined(__alpha) && !defined(__bsdi) +#define BIT_SWAPPED_MAC_ADDRS +#endif + +#ifdef BIT_SWAPPED_MAC_ADDRS +/* "swaptab[i]" is the value of "i" with the bits reversed. */ +static u_char swaptab[256] = { + 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, + 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, + 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, + 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, + 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, + 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, + 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, + 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, + 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, + 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, + 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, + 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, + 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, + 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, + 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, + 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, + 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, + 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, + 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, + 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, + 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, + 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, + 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, + 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, + 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, + 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, + 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, + 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, + 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, + 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, + 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, + 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff, +}; +#endif + +static void get_mac_addr(u_char *swapped_addr, const u_char *addr) { + int i; + for (i = 0; i < 6; i++) { +#ifdef BIT_SWAPPED_MAC_ADDRS + swapped_addr[i] = swaptab[addr[i]]; +#else + swapped_addr[i] = addr[i]; +#endif + } +} + +void dissect_fddi(const u_char *pd, frame_data *fd, GtkTree *tree) +{ int offset = 0, fc; GtkWidget *fh_tree, *ti; + u_char src[6], dst[6]; if (fd->cap_len < FDDI_HEADER_SIZE) { dissect_data(pd, offset, fd, tree); return; } + /* Extract the source and destination addresses, possibly bit-swapping + them. */ + get_mac_addr(dst, (u_char *)&pd[FDDI_P_DHOST]); + get_mac_addr(src, (u_char *)&pd[FDDI_P_SHOST]); + fc = (int) pd[FDDI_P_FC]; if (fd->win_info[COL_NUM]) { - strcpy(fd->win_info[COL_DESTINATION], get_ether_name((u_char *)&pd[FDDI_P_DHOST])); - strcpy(fd->win_info[COL_SOURCE], get_ether_name((u_char *)&pd[FDDI_P_SHOST])); + strcpy(fd->win_info[COL_DESTINATION], get_ether_name(dst)); + strcpy(fd->win_info[COL_SOURCE], get_ether_name(src)); strcpy(fd->win_info[COL_INFO], "FDDI"); } @@ -103,11 +164,9 @@ void dissect_fddi(const u_char *pd, frame_data *fd, GtkTree *tree) add_subtree(ti, fh_tree, ETT_FDDI); add_item_to_tree(fh_tree, FDDI_P_FC, 1, "Frame Control: 0x%02x", fc); add_item_to_tree(fh_tree, FDDI_P_DHOST, 6, "Destination: %s (%s)", - ether_to_str((guint8 *) &pd[FDDI_P_DHOST]), - get_ether_name((u_char *) &pd[FDDI_P_DHOST])); + ether_to_str(dst), get_ether_name(dst)); add_item_to_tree(fh_tree, FDDI_P_SHOST, 6, "Source: %s (%s)", - ether_to_str((guint8 *) &pd[FDDI_P_SHOST]), - get_ether_name((u_char *)&pd[FDDI_P_SHOST])); + ether_to_str(src), get_ether_name(src)); } offset = FDDI_HEADER_SIZE; -- cgit v1.2.3