| /* |
| * Copyright (c) 1992, 1993, 1994, 1995, 1996 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that: (1) source code distributions |
| * retain the above copyright notice and this paragraph in its entirety, (2) |
| * distributions including binary code include the above copyright notice and |
| * this paragraph in its entirety in the documentation or other materials |
| * provided with the distribution, and (3) all advertising materials mentioning |
| * features or use of this software display the following acknowledgement: |
| * ``This product includes software developed by the University of California, |
| * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| * the University nor the names of its contributors may be used to endorse |
| * or promote products derived from this software without specific prior |
| * written permission. |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| * |
| * Original code by Matt Thomas, Digital Equipment Corporation |
| * |
| * Extensively modified by Hannes Gredler (hannes@juniper.net) for more |
| * complete IS-IS support. |
| */ |
| |
| #ifndef lint |
| static const char rcsid[] = |
| "@(#) $Header: /tcpdump/master/tcpdump/print-isoclns.c,v 1.26 2001-09-17 21:58:04 fenner Exp $ (LBL)"; |
| #endif |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <sys/types.h> |
| #include <sys/time.h> |
| #include <sys/socket.h> |
| |
| #include <netinet/in.h> |
| |
| #include <stdio.h> |
| #include <string.h> |
| |
| #include "interface.h" |
| #include "addrtoname.h" |
| #include "ethertype.h" |
| #include "ether.h" |
| #include "extract.h" |
| |
| #define NLPID_CLNS 129 /* 0x81 */ |
| #define NLPID_ESIS 130 /* 0x82 */ |
| #define NLPID_ISIS 131 /* 0x83 */ |
| #define NLPID_IP6 0x8e |
| #define NLPID_IP 0xcc |
| #define NLPID_NULLNS 0 |
| |
| /* |
| * IS-IS is defined in ISO 10589. Look there for protocol definitions. |
| */ |
| |
| #define SYSTEM_ID_LEN ETHER_ADDR_LEN |
| #define ISIS_VERSION 1 |
| #define PDU_TYPE_MASK 0x1F |
| #define PRIORITY_MASK 0x7F |
| |
| #define L1_LAN_IIH 15 |
| #define L2_LAN_IIH 16 |
| #define PTP_IIH 17 |
| #define L1_LSP 18 |
| #define L2_LSP 20 |
| #define L1_CSNP 24 |
| #define L2_CSNP 25 |
| #define L1_PSNP 26 |
| #define L2_PSNP 27 |
| |
| |
| /* |
| * A TLV is a tuple of a type, length and a value and is normally used for |
| * encoding information in all sorts of places. This is an enumeration of |
| * the well known types. |
| */ |
| |
| #define TLV_AREA_ADDR 1 |
| #define TLV_IS_REACH 2 |
| #define TLV_ES_REACH 3 |
| #define TLV_SUMMARY 5 |
| #define TLV_ISNEIGH 6 |
| #define TLV_PADDING 8 |
| #define TLV_LSP 9 |
| #define TLV_AUTH 10 |
| #define TLV_CHECKSUM 12 |
| #define TLV_EXT_IS_REACH 22 |
| #define TLV_IP_REACH 128 |
| #define TLV_PROTOCOLS 129 |
| #define TLV_IP_REACH_EXT 130 |
| #define TLV_IDRP_INFO 131 |
| #define TLV_IPADDR 132 |
| #define TLV_IPAUTH 133 |
| #define TLV_TE_ROUTER_ID 134 |
| #define TLV_EXT_IP_REACH 135 |
| #define TLV_HOSTNAME 137 |
| #define TLV_MT_IS_REACH 222 |
| #define TLV_MT_SUPPORTED 229 |
| #define TLV_IP6ADDR 232 |
| #define TLV_MT_REACH 235 |
| #define TLV_IP6_REACH 236 |
| #define TLV_PTP_ADJ 240 |
| |
| #define SUBTLV_EXT_IS_REACH_ADMIN_GROUP 3 |
| #define SUBTLV_EXT_IS_REACH_IPV4_INTF_ADDR 6 |
| #define SUBTLV_EXT_IS_REACH_IPV4_NEIGHBOR_ADDR 8 |
| #define SUBTLV_EXT_IS_REACH_MAX_LINK_BW 9 |
| #define SUBTLV_EXT_IS_REACH_RESERVABLE_BW 10 |
| #define SUBTLV_EXT_IS_REACH_UNRESERVED_BW 11 |
| #define SUBTLV_EXT_IS_REACH_TE_METRIC 18 |
| |
| #define SUBTLV_AUTH_SIMPLE 1 |
| #define SUBTLV_AUTH_MD5 54 |
| |
| #define ISIS_MASK_LEVEL_BITS(x) ((x)&0x1) |
| #define ISIS_MASK_LSP_OL_BIT(x) ((x)&0x4) |
| #define ISIS_MASK_LSP_ISTYPE_BITS(x) ((x)&0x3) |
| #define ISIS_MASK_LSP_PARTITION_BIT(x) ((x)&0x80) |
| #define ISIS_MASK_LSP_ATT_BITS(x) ((x)&0x78) |
| #define ISIS_MASK_LSP_ATT_ERROR_BIT(x) ((x)&0x40) |
| #define ISIS_MASK_LSP_ATT_EXPENSE_BIT(x) ((x)&0x20) |
| #define ISIS_MASK_LSP_ATT_DELAY_BIT(x) ((x)&0x10) |
| #define ISIS_MASK_LSP_ATT_DEFAULT_BIT(x) ((x)&0x8) |
| #define ISIS_MASK_TLV_EXT_IP_UPDOWN(x) ((x)&0x80) |
| #define ISIS_MASK_TLV_EXT_IP_SUBTLV(x) ((x)&0x40) |
| |
| #define ISIS_LSP_TLV_METRIC_SUPPORTED(x) ((x)&0x80) |
| #define ISIS_LSP_TLV_METRIC_IE(x) ((x)&0x40) |
| #define ISIS_LSP_TLV_METRIC_UPDOWN(x) ((x)&0x80) |
| #define ISIS_LSP_TLV_METRIC_VALUE(x) ((x)&0x3f) |
| |
| #define ISIS_LSP_TYPE_UNUSED0 0 |
| #define ISIS_LSP_TYPE_LEVEL_1 1 |
| #define ISIS_LSP_TYPE_UNUSED2 2 |
| #define ISIS_LSP_TYPE_LEVEL_2 3 |
| |
| static struct tok isis_lsp_istype_values[] = { |
| { ISIS_LSP_TYPE_UNUSED0, "Unused 0x0 (invalid)"}, |
| { ISIS_LSP_TYPE_LEVEL_1, "Level 1 IS"}, |
| { ISIS_LSP_TYPE_UNUSED2, "Unused 0x2 (invalid)"}, |
| { ISIS_LSP_TYPE_LEVEL_2, "Level 2 IS"}, |
| { 0, NULL } |
| }; |
| |
| static struct tok isis_nlpid_values[] = { |
| { NLPID_CLNS, "CLNS"}, |
| { NLPID_IP, "IPv4"}, |
| { NLPID_IP6, "IPv6"}, |
| { 0, "unknown" } |
| }; |
| |
| /* |
| * Katz's point to point adjacency TLV uses codes to tell us the state of |
| * the remote adjacency. Enumerate them. |
| */ |
| |
| #define ISIS_PTP_ADJ_UP 0 |
| #define ISIS_PTP_ADJ_INIT 1 |
| #define ISIS_PTP_ADJ_DOWN 2 |
| |
| static int osi_cksum(const u_char *, u_int, u_char *); |
| static void esis_print(const u_char *, u_int); |
| static int isis_print(const u_char *, u_int); |
| |
| |
| static struct tok isis_ptp_adjancey_values[] = { |
| { ISIS_PTP_ADJ_UP, "Up" }, |
| { ISIS_PTP_ADJ_INIT, "Initializing" }, |
| { ISIS_PTP_ADJ_DOWN, "Down" } |
| }; |
| |
| struct isis_tlv_ptp_adj { |
| u_char adjacency_state; |
| u_char ext_local_circuit_id[4]; |
| u_char neighbor_sysid[SYSTEM_ID_LEN]; |
| u_char neighbor_ext_local_circuit_id[4]; |
| }; |
| |
| struct isis_tlv_ip_reach { |
| u_char metric_default; |
| u_char metric_delay; |
| u_char metric_expense; |
| u_char metric_error; |
| u_char prefix[4]; |
| u_char mask[4]; |
| }; |
| |
| struct isis_tlv_is_reach { |
| u_char virtual_flag; |
| u_char metric_default; |
| u_char metric_delay; |
| u_char metric_expense; |
| u_char metric_error; |
| u_char neighbor_nodeid[SYSTEM_ID_LEN+1]; |
| }; |
| |
| |
| struct isis_common_header { |
| u_char nlpid; |
| u_char fixed_len; |
| u_char version; /* Protocol version? */ |
| u_char id_length; |
| u_char pdu_type; /* 3 MSbs are reserved */ |
| u_char pkt_version; /* Packet format version? */ |
| u_char reserved; |
| u_char max_area; |
| }; |
| |
| struct isis_iih_lan_header { |
| u_char circuit_type; |
| u_char source_id[SYSTEM_ID_LEN]; |
| u_char holding_time[2]; |
| u_char packet_len[2]; |
| u_char priority; |
| u_char lan_id[SYSTEM_ID_LEN+1]; |
| }; |
| |
| struct isis_iih_ptp_header { |
| u_char circuit_type; |
| u_char source_id[SYSTEM_ID_LEN]; |
| u_char holding_time[2]; |
| u_char packet_len[2]; |
| u_char circuit_id; |
| }; |
| |
| struct isis_lsp_header { |
| u_char pdu_len[2]; |
| u_char remaining_lifetime[2]; |
| u_char lsp_id[SYSTEM_ID_LEN+2]; |
| u_char sequence_number[4]; |
| u_char checksum[2]; |
| u_char typeblock; |
| }; |
| |
| struct isis_csnp_header { |
| u_char pdu_len[2]; |
| u_char source_id[SYSTEM_ID_LEN+1]; |
| u_char start_lsp_id[SYSTEM_ID_LEN+2]; |
| u_char end_lsp_id[SYSTEM_ID_LEN+2]; |
| }; |
| |
| struct isis_psnp_header { |
| u_char pdu_len[2]; |
| u_char source_id[SYSTEM_ID_LEN+1]; |
| }; |
| |
| struct isis_tlv_lsp { |
| u_char remaining_lifetime[2]; |
| u_char lsp_id[SYSTEM_ID_LEN+2]; |
| u_char sequence_number[4]; |
| u_char checksum[2]; |
| }; |
| |
| #define ISIS_COMMON_HEADER_SIZE (sizeof(struct isis_common_header)) |
| #define ISIS_IIH_LAN_HEADER_SIZE (sizeof(struct isis_iih_lan_header)) |
| #define ISIS_IIH_PTP_HEADER_SIZE (sizeof(struct isis_iih_ptp_header)) |
| #define ISIS_LSP_HEADER_SIZE (sizeof(struct isis_lsp_header)) |
| #define ISIS_CSNP_HEADER_SIZE (sizeof(struct isis_csnp_header)) |
| #define ISIS_PSNP_HEADER_SIZE (sizeof(struct isis_psnp_header)) |
| |
| void isoclns_print(const u_char *p, u_int length, u_int caplen, |
| const u_char *esrc, const u_char *edst) |
| { |
| u_char pdu_type; |
| const struct isis_common_header *header; |
| |
| header = (const struct isis_common_header *)p; |
| pdu_type = header->pdu_type & PDU_TYPE_MASK; |
| |
| if (caplen < 1) { |
| printf("[|iso-clns] "); |
| if (!eflag && esrc != NULL && edst != NULL) |
| printf("%s > %s", |
| etheraddr_string(esrc), |
| etheraddr_string(edst)); |
| return; |
| } |
| |
| switch (*p) { |
| |
| case NLPID_CLNS: |
| (void)printf("CLNS(%d)", length); |
| if (!eflag && esrc != NULL && edst != NULL) |
| (void)printf(", %s > %s", |
| etheraddr_string(esrc), |
| etheraddr_string(edst)); |
| break; |
| |
| case NLPID_ESIS: |
| (void)printf("ESIS"); |
| if (!eflag && esrc != NULL && edst != NULL) |
| (void)printf(", %s > %s", |
| etheraddr_string(esrc), |
| etheraddr_string(edst)); |
| esis_print(p, length); |
| return; |
| |
| case NLPID_ISIS: |
| (void)printf("ISIS(%d)", length); |
| if (!eflag && esrc != NULL && edst != NULL) |
| (void)printf(", %s > %s", |
| etheraddr_string(esrc), |
| etheraddr_string(edst)); |
| if (!isis_print(p, length)) |
| default_print_unaligned(p, caplen); |
| break; |
| |
| case NLPID_NULLNS: |
| (void)printf("ISO NULLNS(%d)", length); |
| if (!eflag && esrc != NULL && edst != NULL) |
| (void)printf(", %s > %s", |
| etheraddr_string(esrc), |
| etheraddr_string(edst)); |
| break; |
| |
| default: |
| (void)printf("CLNS %02x(%d)", p[0], length); |
| if (!eflag && esrc != NULL && edst != NULL) |
| (void)printf(", %s > %s", |
| etheraddr_string(esrc), |
| etheraddr_string(edst)); |
| if (caplen > 1) |
| default_print_unaligned(p, caplen); |
| break; |
| } |
| } |
| |
| #define ESIS_REDIRECT 6 |
| #define ESIS_ESH 2 |
| #define ESIS_ISH 4 |
| |
| struct esis_hdr { |
| u_char version; |
| u_char reserved; |
| u_char type; |
| u_char tmo[2]; |
| u_char cksum[2]; |
| }; |
| |
| static void |
| esis_print(const u_char *p, u_int length) |
| { |
| const u_char *ep; |
| u_int li = p[1]; |
| const struct esis_hdr *eh = (const struct esis_hdr *) &p[2]; |
| u_char off[2]; |
| |
| if (length == 2) { |
| if (qflag) |
| printf(" bad pkt!"); |
| else |
| printf(" no header at all!"); |
| return; |
| } |
| ep = p + li; |
| if (li > length) { |
| if (qflag) |
| printf(" bad pkt!"); |
| else |
| printf(" LI(%d) > PDU size (%d)!", li, length); |
| return; |
| } |
| if (li < sizeof(struct esis_hdr) + 2) { |
| if (qflag) |
| printf(" bad pkt!"); |
| else { |
| printf(" too short for esis header %d:", li); |
| while (--length != 0) |
| printf("%02X", *p++); |
| } |
| return; |
| } |
| switch (eh->type & 0x1f) { |
| |
| case ESIS_REDIRECT: |
| printf(" redirect"); |
| break; |
| |
| case ESIS_ESH: |
| printf(" esh"); |
| break; |
| |
| case ESIS_ISH: |
| printf(" ish"); |
| break; |
| |
| default: |
| printf(" type %d", eh->type & 0x1f); |
| break; |
| } |
| off[0] = eh->cksum[0]; |
| off[1] = eh->cksum[1]; |
| if (vflag && osi_cksum(p, li, off)) { |
| printf(" bad cksum (got %02x%02x)", |
| eh->cksum[1], eh->cksum[0]); |
| default_print(p, length); |
| return; |
| } |
| if (eh->version != 1) { |
| printf(" unsupported version %d", eh->version); |
| return; |
| } |
| p += sizeof(*eh) + 2; |
| li -= sizeof(*eh) + 2; /* protoid * li */ |
| |
| switch (eh->type & 0x1f) { |
| case ESIS_REDIRECT: { |
| const u_char *dst, *snpa, *is; |
| |
| dst = p; p += *p + 1; |
| if (p > snapend) |
| return; |
| printf("\n\t\t\t %s", isonsap_string(dst)); |
| snpa = p; p += *p + 1; |
| is = p; p += *p + 1; |
| if (p > snapend) |
| return; |
| if (p > ep) { |
| printf(" [bad li]"); |
| return; |
| } |
| if (is[0] == 0) |
| printf(" > %s", etheraddr_string(&snpa[1])); |
| else |
| printf(" > %s", isonsap_string(is)); |
| li = ep - p; |
| break; |
| } |
| #if 0 |
| case ESIS_ESH: |
| printf(" esh"); |
| break; |
| #endif |
| case ESIS_ISH: { |
| const u_char *is; |
| |
| is = p; p += *p + 1; |
| if (p > ep) { |
| printf(" [bad li]"); |
| return; |
| } |
| if (p > snapend) |
| return; |
| if (!qflag) |
| printf("\n\t\t\t %s", isonsap_string(is)); |
| li = ep - p; |
| break; |
| } |
| |
| default: |
| (void)printf(" len=%d", length); |
| if (length && p < snapend) { |
| length = snapend - p; |
| default_print(p, length); |
| } |
| return; |
| } |
| if (vflag) |
| while (p < ep && li) { |
| u_int op, opli; |
| const u_char *q; |
| |
| if (snapend - p < 2) |
| return; |
| if (li < 2) { |
| printf(" bad opts/li"); |
| return; |
| } |
| op = *p++; |
| opli = *p++; |
| li -= 2; |
| if (opli > li) { |
| printf(" opt (%d) too long", op); |
| return; |
| } |
| li -= opli; |
| q = p; |
| p += opli; |
| if (snapend < p) |
| return; |
| if (op == 198 && opli == 2) { |
| printf(" tmo=%d", q[0] * 256 + q[1]); |
| continue; |
| } |
| printf (" %d:<", op); |
| while (opli-- > 0) |
| printf("%02x", *q++); |
| printf (">"); |
| } |
| } |
| |
| /* |
| * print_nsap |
| * Print out an NSAP. |
| */ |
| |
| static void |
| print_nsap (register const u_char *cp, register int length) |
| { |
| int i; |
| |
| for (i = 0; i < length; i++) { |
| printf("%02x", *cp++); |
| if (((i & 1) == 0) && (i + 1 < length)) { |
| printf("."); |
| } |
| |
| } |
| } |
| |
| static void |
| isis_print_sysid (const u_char *cp) |
| { |
| int i; |
| for (i=1;i<=6;i++) { |
| printf("%02x",*cp++); |
| if ( (i==2)^(i==4) ) { |
| printf("."); |
| } |
| } |
| } |
| |
| static void |
| isis_print_nodeid (const u_char *cp) |
| { |
| int i; |
| for (i=1;i<=7;i++) { |
| printf("%02x",*cp++); |
| if ((i & 1) == 0) { |
| printf("."); |
| } |
| } |
| } |
| |
| static void |
| isis_print_lspid (const u_char *cp) |
| { |
| int i; |
| for (i=1;i<=7;i++) { |
| printf("%02x",*cp++); |
| if ((i & 1) == 0) |
| printf("."); |
| } |
| printf("-%02x",*cp); |
| } |
| |
| static void |
| isis_print_tlv_ip_reach (const u_char *cp, int length) |
| { |
| int bitmasks[33] = { |
| 0x00000000, |
| 0x80000000, 0xc0000000, 0xe0000000, 0xf0000000, |
| 0xf8000000, 0xfc000000, 0xfe000000, 0xff000000, |
| 0xff800000, 0xffc00000, 0xffe00000, 0xfff00000, |
| 0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000, |
| 0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000, |
| 0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00, |
| 0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0, |
| 0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff |
| }; |
| |
| int mask,prefix_len; |
| |
| const struct isis_tlv_ip_reach *tlv_ip_reach; |
| tlv_ip_reach = (const struct isis_tlv_ip_reach *)cp; |
| |
| while ( length > 0 ) { |
| if (length<12) { |
| printf("short IP reachability (%d vs 12)", length ); |
| return; |
| } |
| |
| mask=EXTRACT_32BITS(tlv_ip_reach->mask); |
| prefix_len=0; |
| |
| while(prefix_len<=33) { |
| if (bitmasks[prefix_len++]==mask) { |
| prefix_len--; |
| break; |
| } |
| } |
| |
| /* 34 indicates no match -> must be a discontiguous netmask |
| lets dump the mask, otherwise print the prefix_len */ |
| |
| if(prefix_len==34) |
| printf("\n\t\t\tIPv4 prefix: %u.%u.%u.%u mask %u.%u.%u.%u", |
| (tlv_ip_reach->prefix)[0], |
| (tlv_ip_reach->prefix)[1], |
| (tlv_ip_reach->prefix)[2], |
| (tlv_ip_reach->prefix)[3], |
| (tlv_ip_reach->mask)[0], |
| (tlv_ip_reach->mask)[1], |
| (tlv_ip_reach->mask)[2], |
| (tlv_ip_reach->mask)[3]); |
| else |
| printf("\n\t\t\tIPv4 prefix: %u.%u.%u.%u/%u", |
| (tlv_ip_reach->prefix)[0], |
| (tlv_ip_reach->prefix)[1], |
| (tlv_ip_reach->prefix)[2], |
| (tlv_ip_reach->prefix)[3], |
| prefix_len); |
| |
| printf("\n\t\t\t Default Metric: %02d, %s, Distribution: %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->metric_default), |
| ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->metric_default) ? "External" : "Internal", |
| ISIS_LSP_TLV_METRIC_UPDOWN(tlv_ip_reach->metric_default) ? "down" : "up"); |
| |
| if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_ip_reach->metric_delay)) |
| printf("\n\t\t\t Delay Metric: %02d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->metric_delay), |
| ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->metric_delay) ? "External" : "Internal"); |
| |
| if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_ip_reach->metric_expense)) |
| printf("\n\t\t\t Expense Metric: %02d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->metric_expense), |
| ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->metric_expense) ? "External" : "Internal"); |
| |
| if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_ip_reach->metric_error)) |
| printf("\n\t\t\t Error Metric: %02d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->metric_error), |
| ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->metric_error) ? "External" : "Internal"); |
| |
| length-=sizeof(struct isis_tlv_ip_reach); |
| tlv_ip_reach++; |
| } |
| } |
| |
| /* |
| * isis_print |
| * Decode IS-IS packets. Return 0 on error. |
| */ |
| |
| static int isis_print (const u_char *p, u_int length) |
| { |
| const struct isis_common_header *header; |
| |
| const struct isis_iih_lan_header *header_iih_lan; |
| const struct isis_iih_ptp_header *header_iih_ptp; |
| const struct isis_lsp_header *header_lsp; |
| const struct isis_csnp_header *header_csnp; |
| const struct isis_psnp_header *header_psnp; |
| |
| const struct isis_tlv_lsp *tlv_lsp; |
| const struct isis_tlv_ptp_adj *tlv_ptp_adj; |
| const struct isis_tlv_is_reach *tlv_is_reach; |
| |
| u_char pdu_type, max_area, type, len, tmp, alen, subl, subt, tslen, ttslen; |
| const u_char *optr, *pptr, *tptr; |
| u_short packet_len; |
| u_int i,j,bit_length,byte_length,metric; |
| u_char prefix[4]; |
| u_char off[2]; |
| float bw; |
| |
| packet_len=length; |
| optr = p; /* initialize the _o_riginal pointer - need it for parsing the checksum TLV */ |
| header = (const struct isis_common_header *)p; |
| pptr = p+(ISIS_COMMON_HEADER_SIZE); |
| header_iih_lan = (const struct isis_iih_lan_header *)pptr; |
| header_iih_ptp = (const struct isis_iih_ptp_header *)pptr; |
| header_lsp = (const struct isis_lsp_header *)pptr; |
| header_csnp = (const struct isis_csnp_header *)pptr; |
| header_psnp = (const struct isis_psnp_header *)pptr; |
| |
| /* |
| * Sanity checking of the header. |
| */ |
| if (header->nlpid != NLPID_ISIS) { |
| printf(", coding error!"); |
| return(0); |
| } |
| |
| if (header->version != ISIS_VERSION) { |
| printf(", version %d packet not supported", header->version); |
| return(0); |
| } |
| |
| if ((header->id_length != SYSTEM_ID_LEN) && (header->id_length != 0)) { |
| printf(", system ID length of %d is not supported", |
| header->id_length); |
| return(0); |
| } |
| |
| if (header->pkt_version != ISIS_VERSION) { |
| printf(", version %d packet not supported", header->pkt_version); |
| return(0); |
| } |
| |
| max_area = header->max_area; |
| switch(max_area) { |
| case 0: |
| max_area = 3; /* silly shit */ |
| break; |
| case 255: |
| printf(", bad packet -- 255 areas"); |
| return(0); |
| default: |
| break; |
| } |
| |
| printf(", hlen: %u, v: %u, sys-id-len: 6 (0), max-area: %u (%u)", |
| header->fixed_len, |
| header->pkt_version, |
| max_area, |
| header->max_area); |
| |
| pdu_type=header->pdu_type; |
| |
| switch (pdu_type) { |
| |
| case L1_LAN_IIH: |
| case L2_LAN_IIH: |
| if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE)) { |
| printf(", bogus fixed header length %u should be %lu", |
| header->fixed_len, (unsigned long)ISIS_IIH_LAN_HEADER_SIZE); |
| return(0); |
| } |
| printf(", L%s Lan IIH", |
| ISIS_MASK_LEVEL_BITS(pdu_type) ? "2" : "1"); |
| printf("\n\t\t source-id: "); |
| isis_print_sysid(header_iih_lan->source_id); |
| printf(", holding time: %us",EXTRACT_16BITS(header_iih_lan->holding_time)); |
| switch(header_iih_lan->circuit_type) { |
| case 1: |
| printf(", Level 1 only"); |
| break; |
| case 2: |
| printf(", Level 2 only"); |
| break; |
| case 3: |
| printf(", Level 1, Level 2"); |
| break; |
| default: |
| printf(", unknown 0x%02x", header_iih_lan->circuit_type); |
| break; |
| } |
| printf("\n\t\t lan-id: "); |
| isis_print_nodeid(header_iih_lan->lan_id); |
| printf(", Priority: %u",(header_iih_lan->priority) & PRIORITY_MASK); |
| |
| packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE); |
| pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE); |
| break; |
| |
| case PTP_IIH: |
| if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE)) { |
| printf(", bogus fixed header length %u should be %lu", |
| header->fixed_len, (unsigned long)ISIS_IIH_PTP_HEADER_SIZE); |
| return(0); |
| } |
| printf(", PTP IIH"); |
| |
| printf("\n\t\t source-id: "); |
| isis_print_sysid(header_iih_ptp->source_id); |
| printf(", holding time: %us",EXTRACT_16BITS(header_iih_ptp->holding_time)); |
| printf(", circuit-id: 0x%02x", header_iih_ptp->circuit_id); |
| switch(header_iih_ptp->circuit_type) { |
| case 1: |
| printf(", Level 1 only"); |
| break; |
| case 2: |
| printf(", Level 2 only"); |
| break; |
| case 3: |
| printf(", Level 1, Level 2"); |
| break; |
| default: |
| printf(", unknown 0x%02x", header_iih_ptp->circuit_type); |
| break; |
| } |
| |
| packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE); |
| pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE); |
| break; |
| |
| case L1_LSP: |
| case L2_LSP: |
| if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_LSP_HEADER_SIZE)) { |
| printf(", bogus fixed header length %u should be %lu", |
| header->fixed_len, (unsigned long)ISIS_LSP_HEADER_SIZE); |
| return(0); |
| } |
| if ( pdu_type == L1_LSP) |
| printf(", L1 LSP"); |
| if ( pdu_type == L2_LSP) |
| printf(", L2 LSP"); |
| |
| printf("\n\t\t lsp-id: "); |
| isis_print_lspid(header_lsp->lsp_id); |
| printf(", sequence number: 0x%08x",EXTRACT_32BITS(header_lsp->sequence_number)); |
| printf(", lifetime: %5us",EXTRACT_16BITS(header_lsp->remaining_lifetime)); |
| printf("\n\t\t checksum: 0x%04x",EXTRACT_16BITS(header_lsp->checksum)); |
| |
| printf(", %s", ISIS_MASK_LSP_OL_BIT(header_lsp->typeblock) ? "Overload bit set, " : ""); |
| |
| if (ISIS_MASK_LSP_ATT_BITS(header_lsp->typeblock)) { |
| printf("%s", ISIS_MASK_LSP_ATT_DEFAULT_BIT(header_lsp->typeblock) ? "default " : ""); |
| printf("%s", ISIS_MASK_LSP_ATT_DELAY_BIT(header_lsp->typeblock) ? "delay " : ""); |
| printf("%s", ISIS_MASK_LSP_ATT_EXPENSE_BIT(header_lsp->typeblock) ? "expense " : ""); |
| printf("%s", ISIS_MASK_LSP_ATT_ERROR_BIT(header_lsp->typeblock) ? "error " : ""); |
| printf("ATT bit set, "); |
| } |
| printf("%s", ISIS_MASK_LSP_PARTITION_BIT(header_lsp->typeblock) ? "P bit set, " : ""); |
| printf("%s", tok2str(isis_lsp_istype_values,"Unknown(0x%x)",ISIS_MASK_LSP_ISTYPE_BITS(header_lsp->typeblock))); |
| |
| packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_LSP_HEADER_SIZE); |
| pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_LSP_HEADER_SIZE); |
| break; |
| |
| case L1_CSNP: |
| case L2_CSNP: |
| if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE)) { |
| printf(", bogus fixed header length %u should be %lu", |
| header->fixed_len, (unsigned long)ISIS_CSNP_HEADER_SIZE); |
| return(0); |
| } |
| printf(", L%s CSNP", ISIS_MASK_LEVEL_BITS(pdu_type) ? "2" : "1"); |
| printf("\n\t\t source-id: "); |
| isis_print_nodeid(header_csnp->source_id); |
| printf("\n\t\t start lsp-id: "); |
| isis_print_lspid(header_csnp->start_lsp_id); |
| printf("\n\t\t end lsp-id: "); |
| isis_print_lspid(header_csnp->end_lsp_id); |
| |
| packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE); |
| pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE); |
| break; |
| |
| case L1_PSNP: |
| case L2_PSNP: |
| if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE)) { |
| printf("- bogus fixed header length %u should be %lu", |
| header->fixed_len, (unsigned long)ISIS_PSNP_HEADER_SIZE); |
| return(0); |
| } |
| printf(", L%s PSNP", ISIS_MASK_LEVEL_BITS(pdu_type) ? "2" : "1"); |
| printf("\n\t\t source-id: "); |
| isis_print_nodeid(header_psnp->source_id); |
| |
| packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE); |
| pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE); |
| break; |
| default: |
| printf(", PDU type (0x%02x) not supported", pdu_type); |
| return(1); |
| } |
| |
| /* |
| * Now print the TLV's. |
| */ |
| |
| while (packet_len >= 2) { |
| if (pptr == snapend) { |
| return(1); |
| } |
| |
| if (pptr >= snapend) { |
| printf("\n\t\t\t packet exceeded snapshot (%ld) bytes", |
| (long)(pptr-snapend)); |
| return(1); |
| } |
| type = *pptr++; |
| len = *pptr++; |
| packet_len -= 2; |
| if (len > packet_len) { |
| break; |
| } |
| printf("\n\t\t "); |
| |
| switch (type) { |
| case TLV_AREA_ADDR: |
| printf("Area address(es) (%u)",len); |
| tmp = len; |
| tptr = pptr; |
| alen = *tptr++; |
| while (tmp && alen < tmp) { |
| printf("\n\t\t\tArea address (%u): ",alen); |
| print_nsap(tptr, alen); |
| tptr += alen; |
| tmp -= alen + 1; |
| alen = *tptr++; |
| } |
| break; |
| case TLV_ISNEIGH: |
| printf("IS Neighbor(s) (%u)",len); |
| tmp = len; |
| tptr = pptr; |
| while (tmp >= ETHER_ADDR_LEN) { |
| printf("\n\t\t\tIS Neighbor: "); |
| isis_print_sysid(tptr); |
| tmp -= ETHER_ADDR_LEN; |
| tptr += ETHER_ADDR_LEN; |
| } |
| break; |
| |
| case TLV_PADDING: |
| printf("Padding (%u)", len); |
| break; |
| |
| case TLV_MT_IS_REACH: |
| printf("Multi Topology IS Reachability (%u)",len); |
| tptr=pptr; |
| tmp=len; |
| while (tmp>0) { |
| printf("\n\t\t\t"); |
| switch(EXTRACT_16BITS(tptr)&0x0fff) { |
| case 0: |
| printf("IPv4 unicast"); |
| break; |
| case 1: |
| printf("In-Band Management"); |
| break; |
| case 2: |
| printf("IPv6 unicast"); |
| break; |
| case 3: |
| printf("Multicast"); |
| break; |
| case 4095: |
| printf("Development, Experimental or Proprietary"); |
| break; |
| default: |
| printf("Reserved for IETF Consensus"); |
| } |
| printf(" Topology (0x%03x)",EXTRACT_16BITS(tptr)&0x0fff); |
| tptr+=2; |
| printf("\n\t\t\t IS Neighbor: "); |
| isis_print_nodeid(tptr); |
| tptr+=(SYSTEM_ID_LEN+1); |
| printf(", Metric: %d",EXTRACT_24BITS(tptr)); |
| tptr+=3; |
| tslen=*(tptr++); |
| printf(", %ssub-TLVs present",tslen ? "" : "no "); |
| |
| tptr+=tslen; |
| tmp-=(13+tslen); |
| } |
| break; |
| |
| case TLV_EXT_IS_REACH: |
| printf("Extended IS Reachability (%u)",len); |
| tptr=pptr; |
| tmp=len; |
| while (tmp>0) { |
| printf("\n\t\t\tIS Neighbor: "); |
| isis_print_nodeid(tptr); |
| tptr+=(SYSTEM_ID_LEN+1); |
| printf(", Metric: %d",EXTRACT_24BITS(tptr)); |
| tptr+=3; |
| tslen=*(tptr++); |
| printf(", %ssub-TLVs present",tslen ? "" : "no "); |
| if (tslen) { |
| printf(" (%u)",tslen); |
| ttslen=tslen; |
| while (ttslen>0) { |
| printf("\n\t\t\t "); |
| subt=*(tptr++); |
| subl=*(tptr++); |
| switch(subt) { |
| case SUBTLV_EXT_IS_REACH_ADMIN_GROUP: |
| printf("Administrative groups: 0x%08x", EXTRACT_32BITS(tptr)); |
| break; |
| case SUBTLV_EXT_IS_REACH_MAX_LINK_BW : |
| j = EXTRACT_32BITS(tptr); |
| memcpy (&bw, &j, 4); |
| printf("Maximum link bandwidth : %.3f Mbps", |
| bw*8/1000000 ); |
| break; |
| case SUBTLV_EXT_IS_REACH_RESERVABLE_BW : |
| j = EXTRACT_32BITS(tptr); |
| memcpy (&bw, &j, 4); |
| printf("Reservable link bandwidth: %.3f Mbps", |
| bw*8/1000000 ); |
| break; |
| case SUBTLV_EXT_IS_REACH_UNRESERVED_BW : |
| printf("Unreserved bandwidth:"); |
| for (i = 0 ; i < 8 ; i++) { |
| j = EXTRACT_32BITS(tptr); |
| memcpy (&bw, &j, 4); |
| printf("\n\t\t\t priority level %d: %.3f Mbps", |
| i, bw*8/1000000 ); |
| tptr+=4; |
| } |
| tptr-=32; |
| break; |
| case SUBTLV_EXT_IS_REACH_TE_METRIC: |
| printf("Traffic Engineering Metric: %d", EXTRACT_24BITS(tptr)); |
| break; |
| case SUBTLV_EXT_IS_REACH_IPV4_INTF_ADDR: |
| printf("IPv4 interface address: %s", ipaddr_string(tptr)); |
| break; |
| case SUBTLV_EXT_IS_REACH_IPV4_NEIGHBOR_ADDR: |
| printf("IPv4 neighbor address: %s", ipaddr_string(tptr)); |
| break; |
| case 250: |
| case 251: |
| case 252: |
| case 253: |
| case 254: |
| printf("Reserved for cisco specific extensions, type %d, length %d", subt, subl); |
| break; |
| case 255: |
| printf("Reserved for future expansion, type %d, length %d", subt, subl); |
| break; |
| default: |
| printf("unknown subTLV, type %d, length %d", subt, subl); |
| } |
| tptr+=subl; |
| ttslen-=(subl+2); |
| } |
| } |
| tptr+=tslen; |
| tmp-=(11+tslen); |
| } |
| break; |
| case TLV_IS_REACH: |
| printf("IS Reachability (%u)",len); |
| tlv_is_reach = (const struct isis_tlv_is_reach *)pptr; |
| printf("\n\t\t\tIS Neighbor: "); |
| isis_print_nodeid(tlv_is_reach->neighbor_nodeid); |
| |
| tmp = len; |
| while (tmp >= sizeof(struct isis_tlv_is_reach)) { |
| |
| printf(", Default Metric: %d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_is_reach->metric_default), |
| ISIS_LSP_TLV_METRIC_IE(tlv_is_reach->metric_default) ? "External" : "Internal"); |
| |
| if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_is_reach->metric_delay)) |
| printf("\n\t\t\t Delay Metric: %d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_is_reach->metric_delay), |
| ISIS_LSP_TLV_METRIC_IE(tlv_is_reach->metric_delay) ? "External" : "Internal"); |
| |
| if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_is_reach->metric_expense)) |
| printf("\n\t\t\t Expense Metric: %d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_is_reach->metric_expense), |
| ISIS_LSP_TLV_METRIC_IE(tlv_is_reach->metric_expense) ? "External" : "Internal"); |
| |
| if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_is_reach->metric_error)) |
| printf("\n\t\t\t Error Metric: %d, %s", |
| ISIS_LSP_TLV_METRIC_VALUE(tlv_is_reach->metric_error), |
| ISIS_LSP_TLV_METRIC_IE(tlv_is_reach->metric_error) ? "External" : "Internal"); |
| |
| switch (tlv_is_reach->virtual_flag) { |
| case 0: |
| printf(", IsNotVirtual"); |
| break; |
| case 1: |
| printf(", IsVirtual"); |
| break; |
| default: |
| printf(", bogus virtual flag 0x%02x",tlv_is_reach->virtual_flag); |
| break; |
| } |
| |
| tmp -= sizeof(struct isis_tlv_is_reach); |
| tlv_is_reach++; |
| } |
| |
| |
| break; |
| case TLV_IP_REACH: |
| printf("IP Internal reachability (%u)",len); |
| isis_print_tlv_ip_reach(pptr, len); |
| break; |
| |
| case TLV_IP_REACH_EXT: |
| printf("IP External reachability (%u)",len); |
| isis_print_tlv_ip_reach(pptr, len); |
| break; |
| |
| case TLV_EXT_IP_REACH: |
| printf("Extended IP reachability (%u)",len); |
| i=len; |
| tptr=pptr; |
| |
| while (i>0) { |
| memset (prefix, 0, 4); |
| metric = EXTRACT_32BITS(tptr); |
| tptr+=4; |
| |
| j=*(tptr); |
| bit_length = (*(tptr)++&0x3f); |
| byte_length = (bit_length + 7) / 8; |
| memcpy(prefix,tptr,byte_length); |
| |
| printf("\n\t\t\tIPv4 prefix: %u.%u.%u.%u/%d", |
| prefix[0], |
| prefix[1], |
| prefix[2], |
| prefix[3], |
| bit_length); |
| |
| printf("\n\t\t\t Metric: %u, Distribution: %s", |
| metric, |
| ISIS_MASK_TLV_EXT_IP_UPDOWN(j) ? "down" : "up"); |
| |
| printf(", %ssub-TLVs present", |
| ISIS_MASK_TLV_EXT_IP_SUBTLV(j) ? "" : "no "); |
| |
| i-=(5+byte_length); |
| tptr+=byte_length; |
| } |
| break; |
| |
| case TLV_AUTH: |
| printf("Authentication (%u)",len); |
| if(*pptr==SUBTLV_AUTH_SIMPLE) { |
| printf("\n\t\t\tsimple text password: "); |
| for(i=1;i<len;i++) { |
| printf("%c",*(pptr+i)); |
| } |
| } |
| if(*pptr==SUBTLV_AUTH_MD5) { |
| printf("\n\t\t\tMD5 password: "); |
| for(i=1;i<len;i++) { |
| printf("%02x",*(pptr+i)); |
| } |
| } |
| break; |
| case TLV_PTP_ADJ: |
| printf("point-to-point Adjacency State (%u)",len); |
| tlv_ptp_adj = (const struct isis_tlv_ptp_adj *)pptr; |
| i=len; |
| if(i>=1) { |
| printf("\n\t\t\tAdjacency State: %s", |
| tok2str(isis_ptp_adjancey_values, "#0x%x", *pptr)); |
| i--; |
| } |
| if(i>=4) { |
| printf("\n\t\t\tExtended Local circuit ID: 0x%08x", |
| EXTRACT_32BITS(tlv_ptp_adj->ext_local_circuit_id)); |
| i-=4; |
| } |
| if(i>=6) { |
| printf("\n\t\t\tNeighbor SystemID: "); |
| isis_print_sysid(tlv_ptp_adj->neighbor_sysid); |
| i-=6; |
| } |
| if(i>=4) { |
| printf("\n\t\t\tNeighbor Extended Local circuit ID: 0x%08x", |
| EXTRACT_32BITS(tlv_ptp_adj->neighbor_ext_local_circuit_id)); |
| } |
| |
| break; |
| case TLV_PROTOCOLS: |
| printf("Protocols supported (%u)", len); |
| printf("\n\t\t\tNLPID(s): "); |
| for(i=0;i<len;i++) { |
| printf("%s (0x%02x)",tok2str(isis_nlpid_values, "Unknown", *(pptr+i)),*(pptr+i)); |
| if(i<len-1) |
| printf(", "); |
| } |
| break; |
| case TLV_TE_ROUTER_ID: |
| printf("Traffic Engineering Router ID (%u)",len); |
| printf("\n\t\t\tTraffic Engineering Router ID: %s", ipaddr_string(pptr)); |
| break; |
| case TLV_IPADDR: |
| printf("IP Interface address(es) (%u)",len); |
| i=len; |
| while(i>0) { |
| printf("\n\t\t\tIPv4 interface address: %s", ipaddr_string(pptr)); |
| i -=4; |
| } |
| break; |
| |
| case TLV_HOSTNAME: |
| printf("Hostname (%u)", len); |
| printf("\n\t\t\tHostname: "); |
| for(i=0;i<len;i++) { |
| printf("%c",*(pptr+i)); |
| } |
| break; |
| |
| case TLV_LSP: |
| tlv_lsp = (const struct isis_tlv_lsp *)pptr; |
| printf("LSP entries (%u)", len); |
| i=0; |
| while(i<len) { |
| printf("\n\t\t\tlsp-id: "); |
| isis_print_nodeid(tlv_lsp->lsp_id); |
| printf("-%02x",(tlv_lsp->lsp_id)[SYSTEM_ID_LEN+1]); |
| printf("\n\t\t\t sequence number: 0x%08x",EXTRACT_32BITS(tlv_lsp->sequence_number)); |
| printf("\n\t\t\t Remaining lifetime: %5ds",EXTRACT_16BITS(tlv_lsp->remaining_lifetime)); |
| printf("\n\t\t\t checksum: 0x%04x",EXTRACT_16BITS(tlv_lsp->checksum)); |
| i+=sizeof(struct isis_tlv_lsp); |
| tlv_lsp++; |
| } |
| break; |
| |
| case TLV_CHECKSUM: |
| printf("Checksum (%u)", len); |
| printf("\n\t\t\tchecksum: 0x%04x", |
| EXTRACT_16BITS(pptr)); |
| |
| if (osi_cksum(optr, length, off)) |
| printf(" (incorrect)"); |
| else |
| printf(" (correct)"); |
| |
| break; |
| |
| case TLV_MT_SUPPORTED: |
| printf("Multi Topology (%u)",len); |
| i=len; |
| tptr=pptr; |
| while (i>1) { |
| /* length can only be a multiple of 2, otherwise there is |
| something broken -> so decode down until length is 1 */ |
| if (i!=1) |
| { |
| printf("\n\t\t\t"); |
| switch(EXTRACT_16BITS(tptr)&0x0fff) { |
| case 0: |
| printf("IPv4 unicast"); |
| break; |
| case 1: |
| printf("In-Band Management"); |
| break; |
| case 2: |
| printf("IPv6 unicast"); |
| break; |
| case 3: |
| printf("Multicast"); |
| break; |
| case 4095: |
| printf("Development, Experimental or Proprietary"); |
| break; |
| default: |
| printf("Reserved for IETF Consensus"); |
| } |
| printf(" Topology (0x%03x)%s%s", |
| EXTRACT_16BITS(tptr)&0xfff, |
| (EXTRACT_16BITS(tptr)&0x8000) ? "" : ", no sub-TLVs present", |
| (EXTRACT_16BITS(tptr)&0x4000) ? ", ATT bit set" : "" ); |
| } |
| else |
| { |
| printf("\n\t\t\tmalformed MT-ID"); |
| break; |
| } |
| i-=2; |
| tptr+=2; |
| } |
| break; |
| |
| default: |
| printf("unknown TLV, type %d, length %d", type, len); |
| break; |
| } |
| |
| pptr += len; |
| packet_len -= len; |
| } |
| |
| if (packet_len != 0) { |
| printf("\n\t\t\t %d straggler bytes", packet_len); |
| } |
| return(1); |
| } |
| |
| /* |
| * Verify the checksum. See 8473-1, Appendix C, section C.4. |
| */ |
| |
| static int |
| osi_cksum(register const u_char *p, register u_int len, u_char *off) |
| { |
| int32_t c0 = 0, c1 = 0; |
| |
| if ((off[0] == 0) && (off[1] == 0)) |
| return 0; |
| |
| off[0] = off[1] = 0; |
| while ((int)--len >= 0) { |
| c0 += *p++; |
| c0 %= 255; |
| c1 += c0; |
| c1 %= 255; |
| } |
| return (c0 | c1); |
| } |
| |
