diff options
author | Guy Harris <guy@alum.mit.edu> | 2000-12-14 08:20:31 +0000 |
---|---|---|
committer | Guy Harris <guy@alum.mit.edu> | 2000-12-14 08:20:31 +0000 |
commit | 13ca5c39d754c287dc5f9adee86aca9fdc820ec6 (patch) | |
tree | 363c9c33cda7869684bc7b282c80617ff4171021 /packet-ppp.c | |
parent | 33474c33cc86f40655b4b2a51d0b7e131e6cda2b (diff) |
PPP patches from Burke Lau to:
add FCS checking;
support Cisco HDLC format in the PPP dissector;
handle MPLS-over-PPP.
svn path=/trunk/; revision=2754
Diffstat (limited to 'packet-ppp.c')
-rw-r--r-- | packet-ppp.c | 225 |
1 files changed, 224 insertions, 1 deletions
diff --git a/packet-ppp.c b/packet-ppp.c index 8572308122..0055dc1fba 100644 --- a/packet-ppp.c +++ b/packet-ppp.c @@ -1,7 +1,7 @@ /* packet-ppp.c * Routines for ppp packet disassembly * - * $Id: packet-ppp.c,v 1.47 2000/12/04 06:37:44 guy Exp $ + * $Id: packet-ppp.c,v 1.48 2000/12/14 08:20:29 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs <gerald@zing.org> @@ -33,6 +33,7 @@ #endif #include <glib.h> +#include "prefs.h" #include "packet.h" #include "packet-ppp.h" #include "ppptypes.h" @@ -72,6 +73,12 @@ static int hf_mp_sequence_num = -1; static int ett_mp = -1; static int ett_mp_flags = -1; +/* options */ +static gint ppp_fcs_decode = 0; /* 0 = No FCS, 1 = 16 bit FCS, 2 = 32 bit FCS */ +#define NO_FCS 0 +#define FCS_16 1 +#define FCS_32 2 + /* PPP structs and definitions */ typedef struct _e_ppphdr { @@ -99,6 +106,10 @@ static const value_string ppp_vals[] = { {PPP_LQR, "Link Quality Report protocol" }, {PPP_CHAP, "Cryptographic Handshake Auth. Protocol" }, {PPP_CBCP, "Callback Control Protocol" }, + {PPP_MPLS_UNI, "MPLS Uni-cast"}, + {PPP_MPLS_MULTI, "MPLS Multi-cast"}, + {CISCO_IP, "CISCO HDLC IP"}, + {CISCO_SLARP, "CISCO HDLC SLARP"}, {0, NULL } }; @@ -507,10 +518,161 @@ static const ip_tcp_opt ipcp_opts[] = { #define N_IPCP_OPTS (sizeof ipcp_opts / sizeof ipcp_opts[0]) +const unsigned int fcstab_32[256] = + { + 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, + 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, + 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, + 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, + 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, + 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, + 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, + 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, + 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, + 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, + 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, + 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, + 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, + 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, + 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, + 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, + 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, + 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, + 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, + 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, + 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, + 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, + 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, + 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, + 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, + 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, + 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, + 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, + 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, + 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, + 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, + 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, + 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, + 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, + 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, + 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, + 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, + 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, + 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, + 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, + 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, + 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, + 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, + 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, + 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, + 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, + 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, + 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, + 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, + 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, + 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, + 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, + 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, + 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, + 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, + 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, + 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, + 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, + 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, + 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, + 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, + 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, + 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, + 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d + }; + +const unsigned short fcstab_16[256] = { + 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, + 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, + 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, + 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, + 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, + 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, + 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, + 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, + 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, + 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, + 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, + 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, + 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, + 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, + 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, + 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, + 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, + 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, + 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, + 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, + 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, + 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, + 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, + 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, + 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, + 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, + 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, + 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, + 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, + 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, + 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, + 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 + }; + +/* +******************************************************************************* +* DETAILS : Calculate a new FCS-16 given the current FCS-16 and the new data. +******************************************************************************* +*/ +guint16 +fcs16(register guint16 fcs, + tvbuff_t * tvbuff, + guint32 offset, + guint32 len) +{ + guint8 val; + /* Check for Invalid Length */ + if(len == 0) + return(0x0000); + while (len--) { + val = tvb_get_guint8(tvbuff, offset++); + fcs = (guint16)((fcs >> 8) & 0x00ff) ^ + fcstab_16[((guint16)(fcs ^ (guint16)((val) & 0x00ff)) & 0x00ff)]; + } + + return (fcs ^ 0xffff); +} + +/* +******************************************************************************* +* DETAILS : Calculate a new FCS-32 given the current FCS-32 and the new data. +******************************************************************************* +*/ +guint32 +fcs32(guint32 fcs, + tvbuff_t * tvbuff, + guint32 offset, + guint32 len) +{ + guint8 val; + /* Check for invalid Length */ + if(len <= 0) + return(0x00000000); + + while (len--) { + val = tvb_get_guint8(tvbuff, offset++); + fcs = (((fcs) >> 8) ^ fcstab_32[((fcs) ^ (val)) & 0xff]); + } + return (fcs ^ 0xffffffff); +} + void capture_ppp( const u_char *pd, int offset, packet_counts *ld ) { switch (pntohs(&pd[offset + 2])) { case PPP_IP: + case CISCO_IP: capture_ip(pd, offset + 4, ld); break; case PPP_IPX: @@ -1132,6 +1294,8 @@ dissect_ppp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree ) { int proto_offset; tvbuff_t *next_tvb; guint8 byte0; + guint32 rx_fcs_exp; + guint32 rx_fcs_got; CHECK_DISPLAY_AS_DATA(proto_ppp, tvb, pinfo, tree); @@ -1144,6 +1308,13 @@ dissect_ppp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree ) { ph.ppp_prot = tvb_get_ntohs(tvb, 2); proto_offset = 2; } + /* Cisco HDLC format */ + else if (byte0 == 0x0f) { + ph.ppp_addr = tvb_get_guint8(tvb, 0); + ph.ppp_ctl = tvb_get_guint8(tvb, 1); + ph.ppp_prot = tvb_get_ntohs(tvb, 2); + proto_offset = 2; + } else { /* address and control are compressed (NULL) */ ph.ppp_prot = tvb_get_ntohs(tvb, 0); @@ -1167,6 +1338,10 @@ dissect_ppp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree ) { proto_tree_add_text(fh_tree, tvb, 0, 1, "Address: %02x", ph.ppp_addr); proto_tree_add_text(fh_tree, tvb, 1, 1, "Control: %02x", ph.ppp_ctl); } + else if (byte0 == 0x0f) { + proto_tree_add_text(fh_tree, tvb, 0, 1, "Address: %02x", ph.ppp_addr); + proto_tree_add_text(fh_tree, tvb, 1, 1, "Control: %02x", ph.ppp_ctl); + } } next_tvb = tvb_new_subset(tvb, proto_offset, -1, -1); @@ -1175,6 +1350,35 @@ dissect_ppp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree ) { if (check_col(pinfo->fd, COL_PROTOCOL)) col_add_fstr(pinfo->fd, COL_PROTOCOL, "0x%04x", ph.ppp_prot); } + + /* Calculate the FCS check */ + if (ppp_fcs_decode == FCS_16) { + rx_fcs_got = 0; + rx_fcs_exp = fcs16(0xFFFF, tvb, 0, tvb_length(tvb) - 2); + rx_fcs_got = tvb_get_guint8(tvb, tvb_length(tvb) - 2) | + (tvb_get_guint8(tvb, tvb_length(tvb) - 1) << 8); + if (rx_fcs_got != rx_fcs_exp) { + proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 2, 2, "FCS 16: %04x (incorrect, should be %04x)", rx_fcs_got, rx_fcs_exp); + } + else { + proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 2, 2, "FCS 16: %04x (correct)", rx_fcs_got); + } + } + else if(ppp_fcs_decode == FCS_32) { + rx_fcs_got = 0; + rx_fcs_exp = fcs32(0xFFFFFFFF, tvb, 0, tvb_length(tvb) - 4); + rx_fcs_got = tvb_get_guint8(tvb, tvb_length(tvb) - 4) | + (tvb_get_guint8(tvb, tvb_length(tvb) - 3) << 8) | + (tvb_get_guint8(tvb, tvb_length(tvb) - 2) << 16) | + (tvb_get_guint8(tvb, tvb_length(tvb) - 1) << 24); + if (rx_fcs_got != rx_fcs_exp) { + proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 4, 4, "FCS 32: %08x (incorrect, should be %08x) ", rx_fcs_got, rx_fcs_exp); + } + else { + proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 4, 4, "FCS 32: %08x (correct)", rx_fcs_got); + } + } + } void @@ -1204,6 +1408,15 @@ proto_register_ppp(void) &ett_lcp_internationalization_opt, }; + static enum_val_t ppp_options[] = { + {"None", 0}, + {"16-Bit", 1}, + {"32-Bit", 2}, + {NULL, -1} + }; + + module_t *ppp_module; + proto_ppp = proto_register_protocol("Point-to-Point Protocol", "ppp"); /* proto_register_field_array(proto_ppp, hf, array_length(hf));*/ proto_register_subtree_array(ett, array_length(ett)); @@ -1213,6 +1426,16 @@ proto_register_ppp(void) register_dissector("ppp", dissect_ppp); register_dissector("payload_ppp", dissect_payload_ppp); + + /* Register the preferences for the ppp protocol */ + ppp_module = prefs_register_module("ppp", "PPP", NULL); + + prefs_register_enum_preference(ppp_module, + "ppp_fcs", + "PPP Frame Checksum", + "PPP Frame Checksum", + &ppp_fcs_decode, + ppp_options, FALSE); } void |