1 /* ocsp_ht.c */ 2 /* Written by Dr Stephen N Henson (steve (at) openssl.org) for the OpenSSL 3 * project 2006. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2006 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing (at) OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay (at) cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh (at) cryptsoft.com). 56 * 57 */ 58 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <ctype.h> 62 #include <string.h> 63 #include "e_os.h" 64 #include <openssl/asn1.h> 65 #include <openssl/ocsp.h> 66 #include <openssl/err.h> 67 #include <openssl/buffer.h> 68 #ifdef OPENSSL_SYS_SUNOS 69 #define strtoul (unsigned long)strtol 70 #endif /* OPENSSL_SYS_SUNOS */ 71 72 /* Stateful OCSP request code, supporting non-blocking I/O */ 73 74 /* Opaque OCSP request status structure */ 75 76 struct ocsp_req_ctx_st { 77 int state; /* Current I/O state */ 78 unsigned char *iobuf; /* Line buffer */ 79 int iobuflen; /* Line buffer length */ 80 BIO *io; /* BIO to perform I/O with */ 81 BIO *mem; /* Memory BIO response is built into */ 82 unsigned long asn1_len; /* ASN1 length of response */ 83 }; 84 85 #define OCSP_MAX_REQUEST_LENGTH (100 * 1024) 86 #define OCSP_MAX_LINE_LEN 4096; 87 88 /* OCSP states */ 89 90 /* If set no reading should be performed */ 91 #define OHS_NOREAD 0x1000 92 /* Error condition */ 93 #define OHS_ERROR (0 | OHS_NOREAD) 94 /* First line being read */ 95 #define OHS_FIRSTLINE 1 96 /* MIME headers being read */ 97 #define OHS_HEADERS 2 98 /* OCSP initial header (tag + length) being read */ 99 #define OHS_ASN1_HEADER 3 100 /* OCSP content octets being read */ 101 #define OHS_ASN1_CONTENT 4 102 /* Request being sent */ 103 #define OHS_ASN1_WRITE (6 | OHS_NOREAD) 104 /* Request being flushed */ 105 #define OHS_ASN1_FLUSH (7 | OHS_NOREAD) 106 /* Completed */ 107 #define OHS_DONE (8 | OHS_NOREAD) 108 109 110 static int parse_http_line1(char *line); 111 112 void OCSP_REQ_CTX_free(OCSP_REQ_CTX *rctx) 113 { 114 if (rctx->mem) 115 BIO_free(rctx->mem); 116 if (rctx->iobuf) 117 OPENSSL_free(rctx->iobuf); 118 OPENSSL_free(rctx); 119 } 120 121 int OCSP_REQ_CTX_set1_req(OCSP_REQ_CTX *rctx, OCSP_REQUEST *req) 122 { 123 static const char req_hdr[] = 124 "Content-Type: application/ocsp-request\r\n" 125 "Content-Length: %d\r\n\r\n"; 126 if (BIO_printf(rctx->mem, req_hdr, i2d_OCSP_REQUEST(req, NULL)) <= 0) 127 return 0; 128 if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0) 129 return 0; 130 rctx->state = OHS_ASN1_WRITE; 131 rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL); 132 return 1; 133 } 134 135 int OCSP_REQ_CTX_add1_header(OCSP_REQ_CTX *rctx, 136 const char *name, const char *value) 137 { 138 if (!name) 139 return 0; 140 if (BIO_puts(rctx->mem, name) <= 0) 141 return 0; 142 if (value) 143 { 144 if (BIO_write(rctx->mem, ": ", 2) != 2) 145 return 0; 146 if (BIO_puts(rctx->mem, value) <= 0) 147 return 0; 148 } 149 if (BIO_write(rctx->mem, "\r\n", 2) != 2) 150 return 0; 151 return 1; 152 } 153 154 OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req, 155 int maxline) 156 { 157 static const char post_hdr[] = "POST %s HTTP/1.0\r\n"; 158 159 OCSP_REQ_CTX *rctx; 160 rctx = OPENSSL_malloc(sizeof(OCSP_REQ_CTX)); 161 rctx->state = OHS_ERROR; 162 rctx->mem = BIO_new(BIO_s_mem()); 163 rctx->io = io; 164 rctx->asn1_len = 0; 165 if (maxline > 0) 166 rctx->iobuflen = maxline; 167 else 168 rctx->iobuflen = OCSP_MAX_LINE_LEN; 169 rctx->iobuf = OPENSSL_malloc(rctx->iobuflen); 170 if (!rctx->iobuf) 171 return 0; 172 if (!path) 173 path = "/"; 174 175 if (BIO_printf(rctx->mem, post_hdr, path) <= 0) 176 return 0; 177 178 if (req && !OCSP_REQ_CTX_set1_req(rctx, req)) 179 return 0; 180 181 return rctx; 182 } 183 184 /* Parse the HTTP response. This will look like this: 185 * "HTTP/1.0 200 OK". We need to obtain the numeric code and 186 * (optional) informational message. 187 */ 188 189 static int parse_http_line1(char *line) 190 { 191 int retcode; 192 char *p, *q, *r; 193 /* Skip to first white space (passed protocol info) */ 194 195 for(p = line; *p && !isspace((unsigned char)*p); p++) 196 continue; 197 if(!*p) 198 { 199 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 200 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 201 return 0; 202 } 203 204 /* Skip past white space to start of response code */ 205 while(*p && isspace((unsigned char)*p)) 206 p++; 207 208 if(!*p) 209 { 210 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 211 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 212 return 0; 213 } 214 215 /* Find end of response code: first whitespace after start of code */ 216 for(q = p; *q && !isspace((unsigned char)*q); q++) 217 continue; 218 219 if(!*q) 220 { 221 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 222 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 223 return 0; 224 } 225 226 /* Set end of response code and start of message */ 227 *q++ = 0; 228 229 /* Attempt to parse numeric code */ 230 retcode = strtoul(p, &r, 10); 231 232 if(*r) 233 return 0; 234 235 /* Skip over any leading white space in message */ 236 while(*q && isspace((unsigned char)*q)) 237 q++; 238 239 if(*q) 240 { 241 /* Finally zap any trailing white space in message (include 242 * CRLF) */ 243 244 /* We know q has a non white space character so this is OK */ 245 for(r = q + strlen(q) - 1; isspace((unsigned char)*r); r--) 246 *r = 0; 247 } 248 if(retcode != 200) 249 { 250 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR); 251 if(!*q) 252 ERR_add_error_data(2, "Code=", p); 253 else 254 ERR_add_error_data(4, "Code=", p, ",Reason=", q); 255 return 0; 256 } 257 258 259 return 1; 260 261 } 262 263 int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx) 264 { 265 int i, n; 266 const unsigned char *p; 267 next_io: 268 if (!(rctx->state & OHS_NOREAD)) 269 { 270 n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen); 271 272 if (n <= 0) 273 { 274 if (BIO_should_retry(rctx->io)) 275 return -1; 276 return 0; 277 } 278 279 /* Write data to memory BIO */ 280 281 if (BIO_write(rctx->mem, rctx->iobuf, n) != n) 282 return 0; 283 } 284 285 switch(rctx->state) 286 { 287 288 case OHS_ASN1_WRITE: 289 n = BIO_get_mem_data(rctx->mem, &p); 290 291 i = BIO_write(rctx->io, 292 p + (n - rctx->asn1_len), rctx->asn1_len); 293 294 if (i <= 0) 295 { 296 if (BIO_should_retry(rctx->io)) 297 return -1; 298 rctx->state = OHS_ERROR; 299 return 0; 300 } 301 302 rctx->asn1_len -= i; 303 304 if (rctx->asn1_len > 0) 305 goto next_io; 306 307 rctx->state = OHS_ASN1_FLUSH; 308 309 (void)BIO_reset(rctx->mem); 310 311 case OHS_ASN1_FLUSH: 312 313 i = BIO_flush(rctx->io); 314 315 if (i > 0) 316 { 317 rctx->state = OHS_FIRSTLINE; 318 goto next_io; 319 } 320 321 if (BIO_should_retry(rctx->io)) 322 return -1; 323 324 rctx->state = OHS_ERROR; 325 return 0; 326 327 case OHS_ERROR: 328 return 0; 329 330 case OHS_FIRSTLINE: 331 case OHS_HEADERS: 332 333 /* Attempt to read a line in */ 334 335 next_line: 336 /* Due to &%^*$" memory BIO behaviour with BIO_gets we 337 * have to check there's a complete line in there before 338 * calling BIO_gets or we'll just get a partial read. 339 */ 340 n = BIO_get_mem_data(rctx->mem, &p); 341 if ((n <= 0) || !memchr(p, '\n', n)) 342 { 343 if (n >= rctx->iobuflen) 344 { 345 rctx->state = OHS_ERROR; 346 return 0; 347 } 348 goto next_io; 349 } 350 n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen); 351 352 if (n <= 0) 353 { 354 if (BIO_should_retry(rctx->mem)) 355 goto next_io; 356 rctx->state = OHS_ERROR; 357 return 0; 358 } 359 360 /* Don't allow excessive lines */ 361 if (n == rctx->iobuflen) 362 { 363 rctx->state = OHS_ERROR; 364 return 0; 365 } 366 367 /* First line */ 368 if (rctx->state == OHS_FIRSTLINE) 369 { 370 if (parse_http_line1((char *)rctx->iobuf)) 371 { 372 rctx->state = OHS_HEADERS; 373 goto next_line; 374 } 375 else 376 { 377 rctx->state = OHS_ERROR; 378 return 0; 379 } 380 } 381 else 382 { 383 /* Look for blank line: end of headers */ 384 for (p = rctx->iobuf; *p; p++) 385 { 386 if ((*p != '\r') && (*p != '\n')) 387 break; 388 } 389 if (*p) 390 goto next_line; 391 392 rctx->state = OHS_ASN1_HEADER; 393 394 } 395 396 /* Fall thru */ 397 398 399 case OHS_ASN1_HEADER: 400 /* Now reading ASN1 header: can read at least 2 bytes which 401 * is enough for ASN1 SEQUENCE header and either length field 402 * or at least the length of the length field. 403 */ 404 n = BIO_get_mem_data(rctx->mem, &p); 405 if (n < 2) 406 goto next_io; 407 408 /* Check it is an ASN1 SEQUENCE */ 409 if (*p++ != (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED)) 410 { 411 rctx->state = OHS_ERROR; 412 return 0; 413 } 414 415 /* Check out length field */ 416 if (*p & 0x80) 417 { 418 /* If MSB set on initial length octet we can now 419 * always read 6 octets: make sure we have them. 420 */ 421 if (n < 6) 422 goto next_io; 423 n = *p & 0x7F; 424 /* Not NDEF or excessive length */ 425 if (!n || (n > 4)) 426 { 427 rctx->state = OHS_ERROR; 428 return 0; 429 } 430 p++; 431 rctx->asn1_len = 0; 432 for (i = 0; i < n; i++) 433 { 434 rctx->asn1_len <<= 8; 435 rctx->asn1_len |= *p++; 436 } 437 438 if (rctx->asn1_len > OCSP_MAX_REQUEST_LENGTH) 439 { 440 rctx->state = OHS_ERROR; 441 return 0; 442 } 443 444 rctx->asn1_len += n + 2; 445 } 446 else 447 rctx->asn1_len = *p + 2; 448 449 rctx->state = OHS_ASN1_CONTENT; 450 451 /* Fall thru */ 452 453 case OHS_ASN1_CONTENT: 454 n = BIO_get_mem_data(rctx->mem, &p); 455 if (n < (int)rctx->asn1_len) 456 goto next_io; 457 458 459 *presp = d2i_OCSP_RESPONSE(NULL, &p, rctx->asn1_len); 460 if (*presp) 461 { 462 rctx->state = OHS_DONE; 463 return 1; 464 } 465 466 rctx->state = OHS_ERROR; 467 return 0; 468 469 break; 470 471 case OHS_DONE: 472 return 1; 473 474 } 475 476 477 478 return 0; 479 480 481 } 482 483 /* Blocking OCSP request handler: now a special case of non-blocking I/O */ 484 485 OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req) 486 { 487 OCSP_RESPONSE *resp = NULL; 488 OCSP_REQ_CTX *ctx; 489 int rv; 490 491 ctx = OCSP_sendreq_new(b, path, req, -1); 492 493 do 494 { 495 rv = OCSP_sendreq_nbio(&resp, ctx); 496 } while ((rv == -1) && BIO_should_retry(b)); 497 498 OCSP_REQ_CTX_free(ctx); 499 500 if (rv) 501 return resp; 502 503 return NULL; 504 } 505