1 /* $OpenBSD: ocsp_ht.c,v 1.21 2014/07/25 06:05:32 doug Exp $ */ 2 /* Written by Dr Stephen N Henson (steve@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@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@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@cryptsoft.com). 56 * 57 */ 58 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <ctype.h> 62 #include <string.h> 63 #include <openssl/asn1.h> 64 #include <openssl/ocsp.h> 65 #include <openssl/err.h> 66 #include <openssl/buffer.h> 67 68 /* Stateful OCSP request code, supporting non-blocking I/O */ 69 70 /* Opaque OCSP request status structure */ 71 72 struct ocsp_req_ctx_st { 73 int state; /* Current I/O state */ 74 unsigned char *iobuf; /* Line buffer */ 75 int iobuflen; /* Line buffer length */ 76 BIO *io; /* BIO to perform I/O with */ 77 BIO *mem; /* Memory BIO response is built into */ 78 unsigned long asn1_len; /* ASN1 length of response */ 79 }; 80 81 #define OCSP_MAX_REQUEST_LENGTH (100 * 1024) 82 #define OCSP_MAX_LINE_LEN 4096; 83 84 /* OCSP states */ 85 86 /* If set no reading should be performed */ 87 #define OHS_NOREAD 0x1000 88 /* Error condition */ 89 #define OHS_ERROR (0 | OHS_NOREAD) 90 /* First line being read */ 91 #define OHS_FIRSTLINE 1 92 /* MIME headers being read */ 93 #define OHS_HEADERS 2 94 /* OCSP initial header (tag + length) being read */ 95 #define OHS_ASN1_HEADER 3 96 /* OCSP content octets being read */ 97 #define OHS_ASN1_CONTENT 4 98 /* Request being sent */ 99 #define OHS_ASN1_WRITE (6 | OHS_NOREAD) 100 /* Request being flushed */ 101 #define OHS_ASN1_FLUSH (7 | OHS_NOREAD) 102 /* Completed */ 103 #define OHS_DONE (8 | OHS_NOREAD) 104 105 106 static int parse_http_line1(char *line); 107 108 void 109 OCSP_REQ_CTX_free(OCSP_REQ_CTX *rctx) 110 { 111 if (rctx == NULL) 112 return; 113 114 BIO_free(rctx->mem); 115 free(rctx->iobuf); 116 free(rctx); 117 } 118 119 int 120 OCSP_REQ_CTX_set1_req(OCSP_REQ_CTX *rctx, OCSP_REQUEST *req) 121 { 122 if (BIO_printf(rctx->mem, "Content-Type: application/ocsp-request\r\n" 123 "Content-Length: %d\r\n\r\n", i2d_OCSP_REQUEST(req, NULL)) <= 0) 124 return 0; 125 if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0) 126 return 0; 127 rctx->state = OHS_ASN1_WRITE; 128 rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL); 129 return 1; 130 } 131 132 int 133 OCSP_REQ_CTX_add1_header(OCSP_REQ_CTX *rctx, const char *name, 134 const char *value) 135 { 136 if (!name) 137 return 0; 138 if (BIO_puts(rctx->mem, name) <= 0) 139 return 0; 140 if (value) { 141 if (BIO_write(rctx->mem, ": ", 2) != 2) 142 return 0; 143 if (BIO_puts(rctx->mem, value) <= 0) 144 return 0; 145 } 146 if (BIO_write(rctx->mem, "\r\n", 2) != 2) 147 return 0; 148 return 1; 149 } 150 151 OCSP_REQ_CTX * 152 OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req, int maxline) 153 { 154 OCSP_REQ_CTX *rctx; 155 156 rctx = malloc(sizeof(OCSP_REQ_CTX)); 157 if (rctx == NULL) 158 return NULL; 159 rctx->state = OHS_ERROR; 160 rctx->mem = BIO_new(BIO_s_mem()); 161 rctx->io = io; 162 rctx->asn1_len = 0; 163 if (maxline > 0) 164 rctx->iobuflen = maxline; 165 else 166 rctx->iobuflen = OCSP_MAX_LINE_LEN; 167 rctx->iobuf = malloc(rctx->iobuflen); 168 if (!rctx->iobuf) { 169 BIO_free(rctx->mem); 170 free(rctx); 171 return NULL; 172 } 173 if (!path) 174 path = "/"; 175 176 if (BIO_printf(rctx->mem, "POST %s HTTP/1.0\r\n", path) <= 0) { 177 free(rctx->iobuf); 178 BIO_free(rctx->mem); 179 free(rctx); 180 return NULL; 181 } 182 183 if (req && !OCSP_REQ_CTX_set1_req(rctx, req)) { 184 free(rctx->iobuf); 185 BIO_free(rctx->mem); 186 free(rctx); 187 return NULL; 188 } 189 190 return rctx; 191 } 192 193 /* Parse the HTTP response. This will look like this: 194 * "HTTP/1.0 200 OK". We need to obtain the numeric code and 195 * (optional) informational message. 196 */ 197 static int 198 parse_http_line1(char *line) 199 { 200 int retcode; 201 char *p, *q, *r; 202 203 /* Skip to first white space (passed protocol info) */ 204 for (p = line; *p && !isspace((unsigned char)*p); p++) 205 continue; 206 if (!*p) { 207 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 208 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 209 return 0; 210 } 211 212 /* Skip past white space to start of response code */ 213 while (*p && isspace((unsigned char)*p)) 214 p++; 215 if (!*p) { 216 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 217 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 218 return 0; 219 } 220 221 /* Find end of response code: first whitespace after start of code */ 222 for (q = p; *q && !isspace((unsigned char)*q); q++) 223 continue; 224 if (!*q) { 225 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 226 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 227 return 0; 228 } 229 230 /* Set end of response code and start of message */ 231 *q++ = 0; 232 233 /* Attempt to parse numeric code */ 234 retcode = strtoul(p, &r, 10); 235 236 if (*r) 237 return 0; 238 239 /* Skip over any leading white space in message */ 240 while (*q && isspace((unsigned char)*q)) 241 q++; 242 if (*q) { 243 /* Finally zap any trailing white space in message (include 244 * CRLF) */ 245 246 /* We know q has a non white space character so this is OK */ 247 for (r = q + strlen(q) - 1; isspace((unsigned char)*r); r--) 248 *r = 0; 249 } 250 if (retcode != 200) { 251 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR); 252 if (!*q) 253 ERR_asprintf_error_data("Code=%s", p); 254 else 255 ERR_asprintf_error_data("Code=%s,Reason=%s", p, q); 256 return 0; 257 } 258 259 return 1; 260 } 261 262 int 263 OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx) 264 { 265 int i, n; 266 const unsigned char *p; 267 268 next_io: 269 if (!(rctx->state & OHS_NOREAD)) { 270 n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen); 271 272 if (n <= 0) { 273 if (BIO_should_retry(rctx->io)) 274 return -1; 275 return 0; 276 } 277 278 /* Write data to memory BIO */ 279 if (BIO_write(rctx->mem, rctx->iobuf, n) != n) 280 return 0; 281 } 282 283 switch (rctx->state) { 284 case OHS_ASN1_WRITE: 285 n = BIO_get_mem_data(rctx->mem, &p); 286 i = BIO_write(rctx->io, 287 p + (n - rctx->asn1_len), rctx->asn1_len); 288 if (i <= 0) { 289 if (BIO_should_retry(rctx->io)) 290 return -1; 291 rctx->state = OHS_ERROR; 292 return 0; 293 } 294 295 rctx->asn1_len -= i; 296 if (rctx->asn1_len > 0) 297 goto next_io; 298 299 rctx->state = OHS_ASN1_FLUSH; 300 301 (void)BIO_reset(rctx->mem); 302 /* FALLTHROUGH */ 303 304 case OHS_ASN1_FLUSH: 305 i = BIO_flush(rctx->io); 306 if (i > 0) { 307 rctx->state = OHS_FIRSTLINE; 308 goto next_io; 309 } 310 311 if (BIO_should_retry(rctx->io)) 312 return -1; 313 314 rctx->state = OHS_ERROR; 315 return 0; 316 317 case OHS_ERROR: 318 return 0; 319 320 case OHS_FIRSTLINE: 321 case OHS_HEADERS: 322 /* Attempt to read a line in */ 323 next_line: 324 /* Due to &%^*$" memory BIO behaviour with BIO_gets we 325 * have to check there's a complete line in there before 326 * calling BIO_gets or we'll just get a partial read. 327 */ 328 n = BIO_get_mem_data(rctx->mem, &p); 329 if ((n <= 0) || !memchr(p, '\n', n)) { 330 if (n >= rctx->iobuflen) { 331 rctx->state = OHS_ERROR; 332 return 0; 333 } 334 goto next_io; 335 } 336 n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen); 337 if (n <= 0) { 338 if (BIO_should_retry(rctx->mem)) 339 goto next_io; 340 rctx->state = OHS_ERROR; 341 return 0; 342 } 343 344 /* Don't allow excessive lines */ 345 if (n == rctx->iobuflen) { 346 rctx->state = OHS_ERROR; 347 return 0; 348 } 349 350 /* First line */ 351 if (rctx->state == OHS_FIRSTLINE) { 352 if (parse_http_line1((char *)rctx->iobuf)) { 353 rctx->state = OHS_HEADERS; 354 goto next_line; 355 } else { 356 rctx->state = OHS_ERROR; 357 return 0; 358 } 359 } else { 360 /* Look for blank line: end of headers */ 361 for (p = rctx->iobuf; *p; p++) { 362 if ((*p != '\r') && (*p != '\n')) 363 break; 364 } 365 if (*p) 366 goto next_line; 367 368 rctx->state = OHS_ASN1_HEADER; 369 } 370 /* FALLTRHOUGH */ 371 372 case OHS_ASN1_HEADER: 373 /* Now reading ASN1 header: can read at least 2 bytes which 374 * is enough for ASN1 SEQUENCE header and either length field 375 * or at least the length of the length field. 376 */ 377 n = BIO_get_mem_data(rctx->mem, &p); 378 if (n < 2) 379 goto next_io; 380 381 /* Check it is an ASN1 SEQUENCE */ 382 if (*p++ != (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED)) { 383 rctx->state = OHS_ERROR; 384 return 0; 385 } 386 387 /* Check out length field */ 388 if (*p & 0x80) { 389 /* If MSB set on initial length octet we can now 390 * always read 6 octets: make sure we have them. 391 */ 392 if (n < 6) 393 goto next_io; 394 n = *p & 0x7F; 395 /* Not NDEF or excessive length */ 396 if (!n || (n > 4)) { 397 rctx->state = OHS_ERROR; 398 return 0; 399 } 400 p++; 401 rctx->asn1_len = 0; 402 for (i = 0; i < n; i++) { 403 rctx->asn1_len <<= 8; 404 rctx->asn1_len |= *p++; 405 } 406 407 if (rctx->asn1_len > OCSP_MAX_REQUEST_LENGTH) { 408 rctx->state = OHS_ERROR; 409 return 0; 410 } 411 412 rctx->asn1_len += n + 2; 413 } else 414 rctx->asn1_len = *p + 2; 415 416 rctx->state = OHS_ASN1_CONTENT; 417 418 /* FALLTHROUGH */ 419 420 case OHS_ASN1_CONTENT: 421 n = BIO_get_mem_data(rctx->mem, &p); 422 if (n < (int)rctx->asn1_len) 423 goto next_io; 424 425 *presp = d2i_OCSP_RESPONSE(NULL, &p, rctx->asn1_len); 426 if (*presp) { 427 rctx->state = OHS_DONE; 428 return 1; 429 } 430 431 rctx->state = OHS_ERROR; 432 return 0; 433 434 case OHS_DONE: 435 return 1; 436 } 437 438 return 0; 439 } 440 441 /* Blocking OCSP request handler: now a special case of non-blocking I/O */ 442 OCSP_RESPONSE * 443 OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req) 444 { 445 OCSP_RESPONSE *resp = NULL; 446 OCSP_REQ_CTX *ctx; 447 int rv; 448 449 ctx = OCSP_sendreq_new(b, path, req, -1); 450 if (ctx == NULL) 451 return NULL; 452 453 do { 454 rv = OCSP_sendreq_nbio(&resp, ctx); 455 } while ((rv == -1) && BIO_should_retry(b)); 456 457 OCSP_REQ_CTX_free(ctx); 458 459 if (rv) 460 return resp; 461 462 return NULL; 463 } 464