1 /* 2 * Copyright (c) 2014 VMware, Inc. All Rights Reserved. 3 * 4 * Jesse Gross <jesse@nicira.com> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that: (1) source code 8 * distributions retain the above copyright notice and this paragraph 9 * in its entirety, and (2) distributions including binary code include 10 * the above copyright notice and this paragraph in its entirety in 11 * the documentation or other materials provided with the distribution. 12 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND 13 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT 14 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 15 * FOR A PARTICULAR PURPOSE. 16 */ 17 18 #define NETDISSECT_REWORKED 19 #ifdef HAVE_CONFIG_H 20 #include "config.h" 21 #endif 22 23 #include <tcpdump-stdinc.h> 24 25 #include "interface.h" 26 #include "extract.h" 27 #include "ethertype.h" 28 29 /* 30 * Geneve header, draft-gross-geneve-02 31 * 32 * 0 1 2 3 33 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 34 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 35 * |Ver| Opt Len |O|C| Rsvd. | Protocol Type | 36 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 37 * | Virtual Network Identifier (VNI) | Reserved | 38 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 39 * | Variable Length Options | 40 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 41 * 42 * Options: 43 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 44 * | Option Class | Type |R|R|R| Length | 45 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 46 * | Variable Option Data | 47 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 48 */ 49 50 #define VER_SHIFT 6 51 #define HDR_OPTS_LEN_MASK 0x3F 52 53 #define FLAG_OAM (1 << 7) 54 #define FLAG_CRITICAL (1 << 6) 55 #define FLAG_R1 (1 << 5) 56 #define FLAG_R2 (1 << 4) 57 #define FLAG_R3 (1 << 3) 58 #define FLAG_R4 (1 << 2) 59 #define FLAG_R5 (1 << 1) 60 #define FLAG_R6 (1 << 0) 61 62 #define OPT_TYPE_CRITICAL (1 << 7) 63 #define OPT_LEN_MASK 0x1F 64 65 static const struct tok geneve_flag_values[] = { 66 { FLAG_OAM, "O" }, 67 { FLAG_CRITICAL, "C" }, 68 { FLAG_R1, "R1" }, 69 { FLAG_R2, "R2" }, 70 { FLAG_R3, "R3" }, 71 { FLAG_R4, "R4" }, 72 { FLAG_R5, "R5" }, 73 { FLAG_R6, "R6" }, 74 { 0, NULL } 75 }; 76 77 static const char * 78 format_opt_class(uint16_t opt_class) 79 { 80 if (opt_class <= 0xff) 81 return "Standard"; 82 else if (opt_class == 0xffff) 83 return "Experimental"; 84 else 85 return "Unknown"; 86 } 87 88 static void 89 geneve_opts_print(netdissect_options *ndo, const u_char *bp, u_int len) 90 { 91 const char *sep = ""; 92 93 while (len > 0) { 94 uint16_t opt_class; 95 uint8_t opt_type; 96 uint8_t opt_len; 97 98 ND_PRINT((ndo, "%s", sep)); 99 sep = ", "; 100 101 opt_class = EXTRACT_16BITS(bp); 102 opt_type = *(bp + 2); 103 opt_len = 4 + ((*(bp + 3) & OPT_LEN_MASK) * 4); 104 105 ND_PRINT((ndo, "class %s (0x%x) type 0x%x%s len %u", 106 format_opt_class(opt_class), opt_class, opt_type, 107 opt_type & OPT_TYPE_CRITICAL ? "(C)" : "", opt_len)); 108 109 if (opt_len > len) { 110 ND_PRINT((ndo, " [bad length]")); 111 return; 112 } 113 114 if (ndo->ndo_vflag > 1 && opt_len > 4) { 115 uint32_t *print_data = (uint32_t *)(bp + 4); 116 int i; 117 118 ND_PRINT((ndo, " data")); 119 120 for (i = 4; i < opt_len; i += 4) { 121 ND_PRINT((ndo, " %08x", EXTRACT_32BITS(print_data))); 122 print_data++; 123 } 124 } 125 126 bp += opt_len; 127 len -= opt_len; 128 } 129 } 130 131 void 132 geneve_print(netdissect_options *ndo, const u_char *bp, u_int len) 133 { 134 uint8_t ver_opt; 135 uint version; 136 uint8_t flags; 137 uint16_t prot; 138 uint32_t vni; 139 uint8_t reserved; 140 u_int opts_len; 141 142 ND_PRINT((ndo, "Geneve")); 143 144 ND_TCHECK2(*bp, 8); 145 146 ver_opt = *bp; 147 bp += 1; 148 len -= 1; 149 150 version = ver_opt >> VER_SHIFT; 151 if (version != 0) { 152 ND_PRINT((ndo, " ERROR: unknown-version %u", version)); 153 return; 154 } 155 156 flags = *bp; 157 bp += 1; 158 len -= 1; 159 160 prot = EXTRACT_16BITS(bp); 161 bp += 2; 162 len -= 2; 163 164 vni = EXTRACT_24BITS(bp); 165 bp += 3; 166 len -= 3; 167 168 reserved = *bp; 169 bp += 1; 170 len -= 1; 171 172 ND_PRINT((ndo, ", Flags [%s]", 173 bittok2str_nosep(geneve_flag_values, "none", flags))); 174 ND_PRINT((ndo, ", vni 0x%x", vni)); 175 176 if (reserved) 177 ND_PRINT((ndo, ", rsvd 0x%x", reserved)); 178 179 if (ndo->ndo_eflag) 180 ND_PRINT((ndo, ", proto %s (0x%04x)", 181 tok2str(ethertype_values, "unknown", prot), prot)); 182 183 opts_len = (ver_opt & HDR_OPTS_LEN_MASK) * 4; 184 185 if (len < opts_len) { 186 ND_PRINT((ndo, " truncated-geneve - %u bytes missing", 187 len - opts_len)); 188 return; 189 } 190 191 ND_TCHECK2(*bp, opts_len); 192 193 if (opts_len > 0) { 194 ND_PRINT((ndo, ", options [")); 195 196 if (ndo->ndo_vflag) 197 geneve_opts_print(ndo, bp, opts_len); 198 else 199 ND_PRINT((ndo, "%u bytes", opts_len)); 200 201 ND_PRINT((ndo, "]")); 202 } 203 204 bp += opts_len; 205 len -= opts_len; 206 207 if (ndo->ndo_vflag < 1) 208 ND_PRINT((ndo, ": ")); 209 else 210 ND_PRINT((ndo, "\n\t")); 211 212 if (ethertype_print(ndo, prot, bp, len, len) == 0) { 213 if (prot == ETHERTYPE_TEB) 214 ether_print(ndo, bp, len, len, NULL, NULL); 215 else 216 ND_PRINT((ndo, "geneve-proto-0x%x", prot)); 217 } 218 219 return; 220 221 trunc: 222 ND_PRINT((ndo, " [|geneve]")); 223 } 224