ns_verify.c revision 1.2.10.2
1 1.2.10.2 msaitoh /* $NetBSD: ns_verify.c,v 1.2.10.2 2013/06/13 04:20:30 msaitoh Exp $ */ 2 1.2.10.2 msaitoh 3 1.2.10.2 msaitoh /* 4 1.2.10.2 msaitoh * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 5 1.2.10.2 msaitoh * Copyright (c) 1999 by Internet Software Consortium, Inc. 6 1.2.10.2 msaitoh * 7 1.2.10.2 msaitoh * Permission to use, copy, modify, and distribute this software for any 8 1.2.10.2 msaitoh * purpose with or without fee is hereby granted, provided that the above 9 1.2.10.2 msaitoh * copyright notice and this permission notice appear in all copies. 10 1.2.10.2 msaitoh * 11 1.2.10.2 msaitoh * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 12 1.2.10.2 msaitoh * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 1.2.10.2 msaitoh * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 14 1.2.10.2 msaitoh * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 1.2.10.2 msaitoh * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 1.2.10.2 msaitoh * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 17 1.2.10.2 msaitoh * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 1.2.10.2 msaitoh */ 19 1.2.10.2 msaitoh 20 1.2.10.2 msaitoh #ifndef lint 21 1.2.10.2 msaitoh static const char rcsid[] = "Id: ns_verify.c,v 1.5 2006/03/09 23:57:56 marka Exp "; 22 1.2.10.2 msaitoh #endif 23 1.2.10.2 msaitoh 24 1.2.10.2 msaitoh /* Import. */ 25 1.2.10.2 msaitoh 26 1.2.10.2 msaitoh #include "port_before.h" 27 1.2.10.2 msaitoh #include "fd_setsize.h" 28 1.2.10.2 msaitoh 29 1.2.10.2 msaitoh #include <sys/types.h> 30 1.2.10.2 msaitoh #include <sys/param.h> 31 1.2.10.2 msaitoh 32 1.2.10.2 msaitoh #include <netinet/in.h> 33 1.2.10.2 msaitoh #include <arpa/nameser.h> 34 1.2.10.2 msaitoh #include <arpa/inet.h> 35 1.2.10.2 msaitoh 36 1.2.10.2 msaitoh #include <errno.h> 37 1.2.10.2 msaitoh #include <netdb.h> 38 1.2.10.2 msaitoh #include <resolv.h> 39 1.2.10.2 msaitoh #include <stdio.h> 40 1.2.10.2 msaitoh #include <stdlib.h> 41 1.2.10.2 msaitoh #include <string.h> 42 1.2.10.2 msaitoh #include <time.h> 43 1.2.10.2 msaitoh #include <unistd.h> 44 1.2.10.2 msaitoh 45 1.2.10.2 msaitoh #include <isc/dst.h> 46 1.2.10.2 msaitoh 47 1.2.10.2 msaitoh #include "port_after.h" 48 1.2.10.2 msaitoh 49 1.2.10.2 msaitoh /* Private. */ 50 1.2.10.2 msaitoh 51 1.2.10.2 msaitoh #define BOUNDS_CHECK(ptr, count) \ 52 1.2.10.2 msaitoh do { \ 53 1.2.10.2 msaitoh if ((ptr) + (count) > eom) { \ 54 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); \ 55 1.2.10.2 msaitoh } \ 56 1.2.10.2 msaitoh } while (/*CONSTCOND*/0) 57 1.2.10.2 msaitoh 58 1.2.10.2 msaitoh /* Public. */ 59 1.2.10.2 msaitoh 60 1.2.10.2 msaitoh u_char * 61 1.2.10.2 msaitoh ns_find_tsig(u_char *msg, u_char *eom) { 62 1.2.10.2 msaitoh HEADER *hp = (void *)msg; 63 1.2.10.2 msaitoh int n, type; 64 1.2.10.2 msaitoh u_char *cp = msg, *start; 65 1.2.10.2 msaitoh 66 1.2.10.2 msaitoh if (msg == NULL || eom == NULL || msg > eom) 67 1.2.10.2 msaitoh return (NULL); 68 1.2.10.2 msaitoh 69 1.2.10.2 msaitoh if (cp + HFIXEDSZ >= eom) 70 1.2.10.2 msaitoh return (NULL); 71 1.2.10.2 msaitoh 72 1.2.10.2 msaitoh if (hp->arcount == 0) 73 1.2.10.2 msaitoh return (NULL); 74 1.2.10.2 msaitoh 75 1.2.10.2 msaitoh cp += HFIXEDSZ; 76 1.2.10.2 msaitoh 77 1.2.10.2 msaitoh n = ns_skiprr(cp, eom, ns_s_qd, ntohs(hp->qdcount)); 78 1.2.10.2 msaitoh if (n < 0) 79 1.2.10.2 msaitoh return (NULL); 80 1.2.10.2 msaitoh cp += n; 81 1.2.10.2 msaitoh 82 1.2.10.2 msaitoh n = ns_skiprr(cp, eom, ns_s_an, ntohs(hp->ancount)); 83 1.2.10.2 msaitoh if (n < 0) 84 1.2.10.2 msaitoh return (NULL); 85 1.2.10.2 msaitoh cp += n; 86 1.2.10.2 msaitoh 87 1.2.10.2 msaitoh n = ns_skiprr(cp, eom, ns_s_ns, ntohs(hp->nscount)); 88 1.2.10.2 msaitoh if (n < 0) 89 1.2.10.2 msaitoh return (NULL); 90 1.2.10.2 msaitoh cp += n; 91 1.2.10.2 msaitoh 92 1.2.10.2 msaitoh n = ns_skiprr(cp, eom, ns_s_ar, ntohs(hp->arcount) - 1); 93 1.2.10.2 msaitoh if (n < 0) 94 1.2.10.2 msaitoh return (NULL); 95 1.2.10.2 msaitoh cp += n; 96 1.2.10.2 msaitoh 97 1.2.10.2 msaitoh start = cp; 98 1.2.10.2 msaitoh n = dn_skipname(cp, eom); 99 1.2.10.2 msaitoh if (n < 0) 100 1.2.10.2 msaitoh return (NULL); 101 1.2.10.2 msaitoh cp += n; 102 1.2.10.2 msaitoh if (cp + INT16SZ >= eom) 103 1.2.10.2 msaitoh return (NULL); 104 1.2.10.2 msaitoh 105 1.2.10.2 msaitoh GETSHORT(type, cp); 106 1.2.10.2 msaitoh if (type != ns_t_tsig) 107 1.2.10.2 msaitoh return (NULL); 108 1.2.10.2 msaitoh return (start); 109 1.2.10.2 msaitoh } 110 1.2.10.2 msaitoh 111 1.2.10.2 msaitoh /* ns_verify 112 1.2.10.2 msaitoh * 113 1.2.10.2 msaitoh * Parameters: 114 1.2.10.2 msaitoh *\li statp res stuff 115 1.2.10.2 msaitoh *\li msg received message 116 1.2.10.2 msaitoh *\li msglen length of message 117 1.2.10.2 msaitoh *\li key tsig key used for verifying. 118 1.2.10.2 msaitoh *\li querysig (response), the signature in the query 119 1.2.10.2 msaitoh *\li querysiglen (response), the length of the signature in the query 120 1.2.10.2 msaitoh *\li sig (query), a buffer to hold the signature 121 1.2.10.2 msaitoh *\li siglen (query), input - length of signature buffer 122 1.2.10.2 msaitoh * output - length of signature 123 1.2.10.2 msaitoh * 124 1.2.10.2 msaitoh * Errors: 125 1.2.10.2 msaitoh *\li - bad input (-1) 126 1.2.10.2 msaitoh *\li - invalid dns message (NS_TSIG_ERROR_FORMERR) 127 1.2.10.2 msaitoh *\li - TSIG is not present (NS_TSIG_ERROR_NO_TSIG) 128 1.2.10.2 msaitoh *\li - key doesn't match (-ns_r_badkey) 129 1.2.10.2 msaitoh *\li - TSIG verification fails with BADKEY (-ns_r_badkey) 130 1.2.10.2 msaitoh *\li - TSIG verification fails with BADSIG (-ns_r_badsig) 131 1.2.10.2 msaitoh *\li - TSIG verification fails with BADTIME (-ns_r_badtime) 132 1.2.10.2 msaitoh *\li - TSIG verification succeeds, error set to BAKEY (ns_r_badkey) 133 1.2.10.2 msaitoh *\li - TSIG verification succeeds, error set to BADSIG (ns_r_badsig) 134 1.2.10.2 msaitoh *\li - TSIG verification succeeds, error set to BADTIME (ns_r_badtime) 135 1.2.10.2 msaitoh */ 136 1.2.10.2 msaitoh int 137 1.2.10.2 msaitoh ns_verify(u_char *msg, int *msglen, void *k, 138 1.2.10.2 msaitoh const u_char *querysig, int querysiglen, u_char *sig, int *siglen, 139 1.2.10.2 msaitoh time_t *timesigned, int nostrip) 140 1.2.10.2 msaitoh { 141 1.2.10.2 msaitoh HEADER *hp = (void *)msg; 142 1.2.10.2 msaitoh DST_KEY *key = (DST_KEY *)k; 143 1.2.10.2 msaitoh u_char *cp = msg, *eom; 144 1.2.10.2 msaitoh char name[MAXDNAME], alg[MAXDNAME]; 145 1.2.10.2 msaitoh u_char *recstart, *rdatastart; 146 1.2.10.2 msaitoh u_char *sigstart, *otherstart; 147 1.2.10.2 msaitoh int n; 148 1.2.10.2 msaitoh int error; 149 1.2.10.2 msaitoh u_int16_t type, length; 150 1.2.10.2 msaitoh u_int16_t fudge, sigfieldlen, otherfieldlen; 151 1.2.10.2 msaitoh 152 1.2.10.2 msaitoh dst_init(); 153 1.2.10.2 msaitoh if (msg == NULL || msglen == NULL || *msglen < 0) 154 1.2.10.2 msaitoh return (-1); 155 1.2.10.2 msaitoh 156 1.2.10.2 msaitoh eom = msg + *msglen; 157 1.2.10.2 msaitoh 158 1.2.10.2 msaitoh recstart = ns_find_tsig(msg, eom); 159 1.2.10.2 msaitoh if (recstart == NULL) 160 1.2.10.2 msaitoh return (NS_TSIG_ERROR_NO_TSIG); 161 1.2.10.2 msaitoh 162 1.2.10.2 msaitoh cp = recstart; 163 1.2.10.2 msaitoh 164 1.2.10.2 msaitoh /* Read the key name. */ 165 1.2.10.2 msaitoh n = dn_expand(msg, eom, cp, name, MAXDNAME); 166 1.2.10.2 msaitoh if (n < 0) 167 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 168 1.2.10.2 msaitoh cp += n; 169 1.2.10.2 msaitoh 170 1.2.10.2 msaitoh /* Read the type. */ 171 1.2.10.2 msaitoh BOUNDS_CHECK(cp, 2*INT16SZ + INT32SZ + INT16SZ); 172 1.2.10.2 msaitoh GETSHORT(type, cp); 173 1.2.10.2 msaitoh if (type != ns_t_tsig) 174 1.2.10.2 msaitoh return (NS_TSIG_ERROR_NO_TSIG); 175 1.2.10.2 msaitoh 176 1.2.10.2 msaitoh /* Skip the class and TTL, save the length. */ 177 1.2.10.2 msaitoh cp += INT16SZ + INT32SZ; 178 1.2.10.2 msaitoh GETSHORT(length, cp); 179 1.2.10.2 msaitoh if (eom - cp != length) 180 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 181 1.2.10.2 msaitoh 182 1.2.10.2 msaitoh /* Read the algorithm name. */ 183 1.2.10.2 msaitoh rdatastart = cp; 184 1.2.10.2 msaitoh n = dn_expand(msg, eom, cp, alg, MAXDNAME); 185 1.2.10.2 msaitoh if (n < 0) 186 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 187 1.2.10.2 msaitoh if (ns_samename(alg, NS_TSIG_ALG_HMAC_MD5) != 1) 188 1.2.10.2 msaitoh return (-ns_r_badkey); 189 1.2.10.2 msaitoh cp += n; 190 1.2.10.2 msaitoh 191 1.2.10.2 msaitoh /* Read the time signed and fudge. */ 192 1.2.10.2 msaitoh BOUNDS_CHECK(cp, INT16SZ + INT32SZ + INT16SZ); 193 1.2.10.2 msaitoh cp += INT16SZ; 194 1.2.10.2 msaitoh GETLONG((*timesigned), cp); 195 1.2.10.2 msaitoh GETSHORT(fudge, cp); 196 1.2.10.2 msaitoh 197 1.2.10.2 msaitoh /* Read the signature. */ 198 1.2.10.2 msaitoh BOUNDS_CHECK(cp, INT16SZ); 199 1.2.10.2 msaitoh GETSHORT(sigfieldlen, cp); 200 1.2.10.2 msaitoh BOUNDS_CHECK(cp, sigfieldlen); 201 1.2.10.2 msaitoh sigstart = cp; 202 1.2.10.2 msaitoh cp += sigfieldlen; 203 1.2.10.2 msaitoh 204 1.2.10.2 msaitoh /* Skip id and read error. */ 205 1.2.10.2 msaitoh BOUNDS_CHECK(cp, 2*INT16SZ); 206 1.2.10.2 msaitoh cp += INT16SZ; 207 1.2.10.2 msaitoh GETSHORT(error, cp); 208 1.2.10.2 msaitoh 209 1.2.10.2 msaitoh /* Parse the other data. */ 210 1.2.10.2 msaitoh BOUNDS_CHECK(cp, INT16SZ); 211 1.2.10.2 msaitoh GETSHORT(otherfieldlen, cp); 212 1.2.10.2 msaitoh BOUNDS_CHECK(cp, otherfieldlen); 213 1.2.10.2 msaitoh otherstart = cp; 214 1.2.10.2 msaitoh cp += otherfieldlen; 215 1.2.10.2 msaitoh 216 1.2.10.2 msaitoh if (cp != eom) 217 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 218 1.2.10.2 msaitoh 219 1.2.10.2 msaitoh /* Verify that the key used is OK. */ 220 1.2.10.2 msaitoh if (key != NULL) { 221 1.2.10.2 msaitoh if (key->dk_alg != KEY_HMAC_MD5) 222 1.2.10.2 msaitoh return (-ns_r_badkey); 223 1.2.10.2 msaitoh if (error != ns_r_badsig && error != ns_r_badkey) { 224 1.2.10.2 msaitoh if (ns_samename(key->dk_key_name, name) != 1) 225 1.2.10.2 msaitoh return (-ns_r_badkey); 226 1.2.10.2 msaitoh } 227 1.2.10.2 msaitoh } 228 1.2.10.2 msaitoh 229 1.2.10.2 msaitoh hp->arcount = htons(ntohs(hp->arcount) - 1); 230 1.2.10.2 msaitoh 231 1.2.10.2 msaitoh /* 232 1.2.10.2 msaitoh * Do the verification. 233 1.2.10.2 msaitoh */ 234 1.2.10.2 msaitoh 235 1.2.10.2 msaitoh if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) { 236 1.2.10.2 msaitoh void *ctx; 237 1.2.10.2 msaitoh u_char buf[MAXDNAME]; 238 1.2.10.2 msaitoh u_char buf2[MAXDNAME]; 239 1.2.10.2 msaitoh 240 1.2.10.2 msaitoh /* Digest the query signature, if this is a response. */ 241 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_INIT, key, &ctx, NULL, 0, NULL, 0); 242 1.2.10.2 msaitoh if (querysiglen > 0 && querysig != NULL) { 243 1.2.10.2 msaitoh u_int16_t len_n = htons(querysiglen); 244 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, 245 1.2.10.2 msaitoh (void *)&len_n, INT16SZ, NULL, 0); 246 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, 247 1.2.10.2 msaitoh querysig, querysiglen, NULL, 0); 248 1.2.10.2 msaitoh } 249 1.2.10.2 msaitoh 250 1.2.10.2 msaitoh /* Digest the message. */ 251 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, msg, 252 1.2.10.2 msaitoh (int)(recstart - msg), NULL, 0); 253 1.2.10.2 msaitoh 254 1.2.10.2 msaitoh /* Digest the key name. */ 255 1.2.10.2 msaitoh n = ns_name_pton(name, buf2, sizeof(buf2)); 256 1.2.10.2 msaitoh if (n < 0) 257 1.2.10.2 msaitoh return (-1); 258 1.2.10.2 msaitoh n = ns_name_ntol(buf2, buf, sizeof(buf)); 259 1.2.10.2 msaitoh if (n < 0) 260 1.2.10.2 msaitoh return (-1); 261 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0); 262 1.2.10.2 msaitoh 263 1.2.10.2 msaitoh /* Digest the class and TTL. */ 264 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, 265 1.2.10.2 msaitoh recstart + dn_skipname(recstart, eom) + INT16SZ, 266 1.2.10.2 msaitoh INT16SZ + INT32SZ, NULL, 0); 267 1.2.10.2 msaitoh 268 1.2.10.2 msaitoh /* Digest the algorithm. */ 269 1.2.10.2 msaitoh n = ns_name_pton(alg, buf2, sizeof(buf2)); 270 1.2.10.2 msaitoh if (n < 0) 271 1.2.10.2 msaitoh return (-1); 272 1.2.10.2 msaitoh n = ns_name_ntol(buf2, buf, sizeof(buf)); 273 1.2.10.2 msaitoh if (n < 0) 274 1.2.10.2 msaitoh return (-1); 275 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0); 276 1.2.10.2 msaitoh 277 1.2.10.2 msaitoh /* Digest the time signed and fudge. */ 278 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, 279 1.2.10.2 msaitoh rdatastart + dn_skipname(rdatastart, eom), 280 1.2.10.2 msaitoh INT16SZ + INT32SZ + INT16SZ, NULL, 0); 281 1.2.10.2 msaitoh 282 1.2.10.2 msaitoh /* Digest the error and other data. */ 283 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, key, &ctx, 284 1.2.10.2 msaitoh otherstart - INT16SZ - INT16SZ, 285 1.2.10.2 msaitoh otherfieldlen + INT16SZ + INT16SZ, NULL, 0); 286 1.2.10.2 msaitoh 287 1.2.10.2 msaitoh n = dst_verify_data(SIG_MODE_FINAL, key, &ctx, NULL, 0, 288 1.2.10.2 msaitoh sigstart, sigfieldlen); 289 1.2.10.2 msaitoh 290 1.2.10.2 msaitoh if (n < 0) 291 1.2.10.2 msaitoh return (-ns_r_badsig); 292 1.2.10.2 msaitoh 293 1.2.10.2 msaitoh if (sig != NULL && siglen != NULL) { 294 1.2.10.2 msaitoh if (*siglen < sigfieldlen) 295 1.2.10.2 msaitoh return (NS_TSIG_ERROR_NO_SPACE); 296 1.2.10.2 msaitoh memcpy(sig, sigstart, sigfieldlen); 297 1.2.10.2 msaitoh *siglen = sigfieldlen; 298 1.2.10.2 msaitoh } 299 1.2.10.2 msaitoh } else { 300 1.2.10.2 msaitoh if (sigfieldlen > 0) 301 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 302 1.2.10.2 msaitoh if (sig != NULL && siglen != NULL) 303 1.2.10.2 msaitoh *siglen = 0; 304 1.2.10.2 msaitoh } 305 1.2.10.2 msaitoh 306 1.2.10.2 msaitoh /* Reset the counter, since we still need to check for badtime. */ 307 1.2.10.2 msaitoh hp->arcount = htons(ntohs(hp->arcount) + 1); 308 1.2.10.2 msaitoh 309 1.2.10.2 msaitoh /* Verify the time. */ 310 1.2.10.2 msaitoh if (abs((int)((*timesigned) - time(NULL))) > fudge) 311 1.2.10.2 msaitoh return (-ns_r_badtime); 312 1.2.10.2 msaitoh 313 1.2.10.2 msaitoh if (nostrip == 0) { 314 1.2.10.2 msaitoh *msglen = (int)(recstart - msg); 315 1.2.10.2 msaitoh hp->arcount = htons(ntohs(hp->arcount) - 1); 316 1.2.10.2 msaitoh } 317 1.2.10.2 msaitoh 318 1.2.10.2 msaitoh if (error != NOERROR) 319 1.2.10.2 msaitoh return (error); 320 1.2.10.2 msaitoh 321 1.2.10.2 msaitoh return (0); 322 1.2.10.2 msaitoh } 323 1.2.10.2 msaitoh 324 1.2.10.2 msaitoh int 325 1.2.10.2 msaitoh ns_verify_tcp_init(void *k, const u_char *querysig, int querysiglen, 326 1.2.10.2 msaitoh ns_tcp_tsig_state *state) 327 1.2.10.2 msaitoh { 328 1.2.10.2 msaitoh dst_init(); 329 1.2.10.2 msaitoh if (state == NULL || k == NULL || querysig == NULL || querysiglen < 0) 330 1.2.10.2 msaitoh return (-1); 331 1.2.10.2 msaitoh state->counter = -1; 332 1.2.10.2 msaitoh state->key = k; 333 1.2.10.2 msaitoh if (state->key->dk_alg != KEY_HMAC_MD5) 334 1.2.10.2 msaitoh return (-ns_r_badkey); 335 1.2.10.2 msaitoh if (querysiglen > (int)sizeof(state->sig)) 336 1.2.10.2 msaitoh return (-1); 337 1.2.10.2 msaitoh memcpy(state->sig, querysig, querysiglen); 338 1.2.10.2 msaitoh state->siglen = querysiglen; 339 1.2.10.2 msaitoh return (0); 340 1.2.10.2 msaitoh } 341 1.2.10.2 msaitoh 342 1.2.10.2 msaitoh int 343 1.2.10.2 msaitoh ns_verify_tcp(u_char *msg, int *msglen, ns_tcp_tsig_state *state, 344 1.2.10.2 msaitoh int required) 345 1.2.10.2 msaitoh { 346 1.2.10.2 msaitoh HEADER *hp = (void *)msg; 347 1.2.10.2 msaitoh u_char *recstart, *sigstart; 348 1.2.10.2 msaitoh unsigned int sigfieldlen, otherfieldlen; 349 1.2.10.2 msaitoh u_char *cp, *eom, *cp2; 350 1.2.10.2 msaitoh char name[MAXDNAME], alg[MAXDNAME]; 351 1.2.10.2 msaitoh u_char buf[MAXDNAME]; 352 1.2.10.2 msaitoh int n, type, length, fudge, error; 353 1.2.10.2 msaitoh time_t timesigned; 354 1.2.10.2 msaitoh 355 1.2.10.2 msaitoh if (msg == NULL || msglen == NULL || state == NULL) 356 1.2.10.2 msaitoh return (-1); 357 1.2.10.2 msaitoh 358 1.2.10.2 msaitoh eom = msg + *msglen; 359 1.2.10.2 msaitoh 360 1.2.10.2 msaitoh state->counter++; 361 1.2.10.2 msaitoh if (state->counter == 0) 362 1.2.10.2 msaitoh return (ns_verify(msg, msglen, state->key, 363 1.2.10.2 msaitoh state->sig, state->siglen, 364 1.2.10.2 msaitoh state->sig, &state->siglen, ×igned, 0)); 365 1.2.10.2 msaitoh 366 1.2.10.2 msaitoh if (state->siglen > 0) { 367 1.2.10.2 msaitoh u_int16_t siglen_n = htons(state->siglen); 368 1.2.10.2 msaitoh 369 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_INIT, state->key, &state->ctx, 370 1.2.10.2 msaitoh NULL, 0, NULL, 0); 371 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, state->key, &state->ctx, 372 1.2.10.2 msaitoh (void *)&siglen_n, INT16SZ, NULL, 0); 373 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, state->key, &state->ctx, 374 1.2.10.2 msaitoh state->sig, state->siglen, NULL, 0); 375 1.2.10.2 msaitoh state->siglen = 0; 376 1.2.10.2 msaitoh } 377 1.2.10.2 msaitoh 378 1.2.10.2 msaitoh cp = recstart = ns_find_tsig(msg, eom); 379 1.2.10.2 msaitoh 380 1.2.10.2 msaitoh if (recstart == NULL) { 381 1.2.10.2 msaitoh if (required) 382 1.2.10.2 msaitoh return (NS_TSIG_ERROR_NO_TSIG); 383 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, state->key, &state->ctx, 384 1.2.10.2 msaitoh msg, *msglen, NULL, 0); 385 1.2.10.2 msaitoh return (0); 386 1.2.10.2 msaitoh } 387 1.2.10.2 msaitoh 388 1.2.10.2 msaitoh hp->arcount = htons(ntohs(hp->arcount) - 1); 389 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, state->key, &state->ctx, 390 1.2.10.2 msaitoh msg, (int)(recstart - msg), NULL, 0); 391 1.2.10.2 msaitoh 392 1.2.10.2 msaitoh /* Read the key name. */ 393 1.2.10.2 msaitoh n = dn_expand(msg, eom, cp, name, MAXDNAME); 394 1.2.10.2 msaitoh if (n < 0) 395 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 396 1.2.10.2 msaitoh cp += n; 397 1.2.10.2 msaitoh 398 1.2.10.2 msaitoh /* Read the type. */ 399 1.2.10.2 msaitoh BOUNDS_CHECK(cp, 2*INT16SZ + INT32SZ + INT16SZ); 400 1.2.10.2 msaitoh GETSHORT(type, cp); 401 1.2.10.2 msaitoh if (type != ns_t_tsig) 402 1.2.10.2 msaitoh return (NS_TSIG_ERROR_NO_TSIG); 403 1.2.10.2 msaitoh 404 1.2.10.2 msaitoh /* Skip the class and TTL, save the length. */ 405 1.2.10.2 msaitoh cp += INT16SZ + INT32SZ; 406 1.2.10.2 msaitoh GETSHORT(length, cp); 407 1.2.10.2 msaitoh if (eom - cp != length) 408 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 409 1.2.10.2 msaitoh 410 1.2.10.2 msaitoh /* Read the algorithm name. */ 411 1.2.10.2 msaitoh n = dn_expand(msg, eom, cp, alg, MAXDNAME); 412 1.2.10.2 msaitoh if (n < 0) 413 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 414 1.2.10.2 msaitoh if (ns_samename(alg, NS_TSIG_ALG_HMAC_MD5) != 1) 415 1.2.10.2 msaitoh return (-ns_r_badkey); 416 1.2.10.2 msaitoh cp += n; 417 1.2.10.2 msaitoh 418 1.2.10.2 msaitoh /* Verify that the key used is OK. */ 419 1.2.10.2 msaitoh if ((ns_samename(state->key->dk_key_name, name) != 1 || 420 1.2.10.2 msaitoh state->key->dk_alg != KEY_HMAC_MD5)) 421 1.2.10.2 msaitoh return (-ns_r_badkey); 422 1.2.10.2 msaitoh 423 1.2.10.2 msaitoh /* Read the time signed and fudge. */ 424 1.2.10.2 msaitoh BOUNDS_CHECK(cp, INT16SZ + INT32SZ + INT16SZ); 425 1.2.10.2 msaitoh cp += INT16SZ; 426 1.2.10.2 msaitoh GETLONG(timesigned, cp); 427 1.2.10.2 msaitoh GETSHORT(fudge, cp); 428 1.2.10.2 msaitoh 429 1.2.10.2 msaitoh /* Read the signature. */ 430 1.2.10.2 msaitoh BOUNDS_CHECK(cp, INT16SZ); 431 1.2.10.2 msaitoh GETSHORT(sigfieldlen, cp); 432 1.2.10.2 msaitoh BOUNDS_CHECK(cp, sigfieldlen); 433 1.2.10.2 msaitoh sigstart = cp; 434 1.2.10.2 msaitoh cp += sigfieldlen; 435 1.2.10.2 msaitoh 436 1.2.10.2 msaitoh /* Skip id and read error. */ 437 1.2.10.2 msaitoh BOUNDS_CHECK(cp, 2*INT16SZ); 438 1.2.10.2 msaitoh cp += INT16SZ; 439 1.2.10.2 msaitoh GETSHORT(error, cp); 440 1.2.10.2 msaitoh 441 1.2.10.2 msaitoh /* Parse the other data. */ 442 1.2.10.2 msaitoh BOUNDS_CHECK(cp, INT16SZ); 443 1.2.10.2 msaitoh GETSHORT(otherfieldlen, cp); 444 1.2.10.2 msaitoh BOUNDS_CHECK(cp, otherfieldlen); 445 1.2.10.2 msaitoh cp += otherfieldlen; 446 1.2.10.2 msaitoh 447 1.2.10.2 msaitoh if (cp != eom) 448 1.2.10.2 msaitoh return (NS_TSIG_ERROR_FORMERR); 449 1.2.10.2 msaitoh 450 1.2.10.2 msaitoh /* 451 1.2.10.2 msaitoh * Do the verification. 452 1.2.10.2 msaitoh */ 453 1.2.10.2 msaitoh 454 1.2.10.2 msaitoh /* Digest the time signed and fudge. */ 455 1.2.10.2 msaitoh cp2 = buf; 456 1.2.10.2 msaitoh PUTSHORT(0, cp2); /*%< Top 16 bits of time. */ 457 1.2.10.2 msaitoh PUTLONG(timesigned, cp2); 458 1.2.10.2 msaitoh PUTSHORT(NS_TSIG_FUDGE, cp2); 459 1.2.10.2 msaitoh 460 1.2.10.2 msaitoh dst_verify_data(SIG_MODE_UPDATE, state->key, &state->ctx, 461 1.2.10.2 msaitoh buf, (int)(cp2 - buf), NULL, 0); 462 1.2.10.2 msaitoh 463 1.2.10.2 msaitoh n = dst_verify_data(SIG_MODE_FINAL, state->key, &state->ctx, NULL, 0, 464 1.2.10.2 msaitoh sigstart, (int)sigfieldlen); 465 1.2.10.2 msaitoh if (n < 0) 466 1.2.10.2 msaitoh return (-ns_r_badsig); 467 1.2.10.2 msaitoh 468 1.2.10.2 msaitoh if (sigfieldlen > sizeof(state->sig)) 469 1.2.10.2 msaitoh return (NS_TSIG_ERROR_NO_SPACE); 470 1.2.10.2 msaitoh 471 1.2.10.2 msaitoh memcpy(state->sig, sigstart, sigfieldlen); 472 1.2.10.2 msaitoh state->siglen = sigfieldlen; 473 1.2.10.2 msaitoh 474 1.2.10.2 msaitoh /* Verify the time. */ 475 1.2.10.2 msaitoh if (abs((int)(timesigned - time(NULL))) > fudge) 476 1.2.10.2 msaitoh return (-ns_r_badtime); 477 1.2.10.2 msaitoh 478 1.2.10.2 msaitoh *msglen = (int)(recstart - msg); 479 1.2.10.2 msaitoh 480 1.2.10.2 msaitoh if (error != NOERROR) 481 1.2.10.2 msaitoh return (error); 482 1.2.10.2 msaitoh 483 1.2.10.2 msaitoh return (0); 484 1.2.10.2 msaitoh } 485 1.2.10.2 msaitoh 486 1.2.10.2 msaitoh /*! \file */ 487
Indexes created Mon Sep 29 21:09:56 GMT 2025