1 /* ocsp_ht.c */ 2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) 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 <openssl/asn1.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <ctype.h> 63 #include <string.h> 64 #include <openssl/ocsp.h> 65 #include <openssl/err.h> 66 #include <openssl/buffer.h> 67 #ifdef OPENSSL_SYS_SUNOS 68 #define strtoul (unsigned long)strtol 69 #endif /* OPENSSL_SYS_SUNOS */ 70 71 /* Stateful OCSP request code, supporting non-blocking I/O */ 72 73 /* Opaque OCSP request status structure */ 74 75 struct ocsp_req_ctx_st { 76 int state; /* Current I/O state */ 77 unsigned char *iobuf; /* Line buffer */ 78 int iobuflen; /* Line buffer length */ 79 BIO *io; /* BIO to perform I/O with */ 80 BIO *mem; /* Memory BIO response is built into */ 81 unsigned long asn1_len; /* ASN1 length of response */ 82 }; 83 84 #define OCSP_MAX_REQUEST_LENGTH (100 * 1024) 85 #define OCSP_MAX_LINE_LEN 4096; 86 87 /* OCSP states */ 88 89 /* If set no reading should be performed */ 90 #define OHS_NOREAD 0x1000 91 /* Error condition */ 92 #define OHS_ERROR (0 | OHS_NOREAD) 93 /* First line being read */ 94 #define OHS_FIRSTLINE 1 95 /* MIME headers being read */ 96 #define OHS_HEADERS 2 97 /* OCSP initial header (tag + length) being read */ 98 #define OHS_ASN1_HEADER 3 99 /* OCSP content octets being read */ 100 #define OHS_ASN1_CONTENT 4 101 /* Request being sent */ 102 #define OHS_ASN1_WRITE (6 | OHS_NOREAD) 103 /* Request being flushed */ 104 #define OHS_ASN1_FLUSH (7 | OHS_NOREAD) 105 /* Completed */ 106 #define OHS_DONE (8 | OHS_NOREAD) 107 108 109 static int parse_http_line1(char *line); 110 111 void OCSP_REQ_CTX_free(OCSP_REQ_CTX *rctx) 112 { 113 if (rctx->mem) 114 BIO_free(rctx->mem); 115 if (rctx->iobuf) 116 OPENSSL_free(rctx->iobuf); 117 OPENSSL_free(rctx); 118 } 119 120 OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req, 121 int maxline) 122 { 123 static char post_hdr[] = "POST %s HTTP/1.0\r\n" 124 "Content-Type: application/ocsp-request\r\n" 125 "Content-Length: %d\r\n\r\n"; 126 127 OCSP_REQ_CTX *rctx; 128 rctx = OPENSSL_malloc(sizeof(OCSP_REQ_CTX)); 129 rctx->state = OHS_FIRSTLINE; 130 rctx->mem = BIO_new(BIO_s_mem()); 131 rctx->io = io; 132 if (maxline > 0) 133 rctx->iobuflen = maxline; 134 else 135 rctx->iobuflen = OCSP_MAX_LINE_LEN; 136 rctx->iobuf = OPENSSL_malloc(rctx->iobuflen); 137 if (!path) 138 path = "/"; 139 140 if (BIO_printf(rctx->mem, post_hdr, path, 141 i2d_OCSP_REQUEST(req, NULL)) <= 0) 142 { 143 rctx->state = OHS_ERROR; 144 return 0; 145 } 146 if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0) 147 { 148 rctx->state = OHS_ERROR; 149 return 0; 150 } 151 rctx->state = OHS_ASN1_WRITE; 152 rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL); 153 154 return rctx; 155 } 156 157 /* Parse the HTTP response. This will look like this: 158 * "HTTP/1.0 200 OK". We need to obtain the numeric code and 159 * (optional) informational message. 160 */ 161 162 static int parse_http_line1(char *line) 163 { 164 int retcode; 165 char *p, *q, *r; 166 /* Skip to first white space (passed protocol info) */ 167 168 for(p = line; *p && !isspace((unsigned char)*p); p++) 169 continue; 170 if(!*p) 171 { 172 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 173 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 174 return 0; 175 } 176 177 /* Skip past white space to start of response code */ 178 while(*p && isspace((unsigned char)*p)) 179 p++; 180 181 if(!*p) 182 { 183 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 184 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 185 return 0; 186 } 187 188 /* Find end of response code: first whitespace after start of code */ 189 for(q = p; *q && !isspace((unsigned char)*q); q++) 190 continue; 191 192 if(!*q) 193 { 194 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, 195 OCSP_R_SERVER_RESPONSE_PARSE_ERROR); 196 return 0; 197 } 198 199 /* Set end of response code and start of message */ 200 *q++ = 0; 201 202 /* Attempt to parse numeric code */ 203 retcode = strtoul(p, &r, 10); 204 205 if(*r) 206 return 0; 207 208 /* Skip over any leading white space in message */ 209 while(*q && isspace((unsigned char)*q)) 210 q++; 211 212 if(*q) 213 { 214 /* Finally zap any trailing white space in message (include 215 * CRLF) */ 216 217 /* We know q has a non white space character so this is OK */ 218 for(r = q + strlen(q) - 1; isspace((unsigned char)*r); r--) 219 *r = 0; 220 } 221 if(retcode != 200) 222 { 223 OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR); 224 if(!*q) 225 ERR_add_error_data(2, "Code=", p); 226 else 227 ERR_add_error_data(4, "Code=", p, ",Reason=", q); 228 return 0; 229 } 230 231 232 return 1; 233 234 } 235 236 int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx) 237 { 238 int i, n; 239 const unsigned char *p; 240 next_io: 241 if (!(rctx->state & OHS_NOREAD)) 242 { 243 n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen); 244 245 if (n <= 0) 246 { 247 if (BIO_should_retry(rctx->io)) 248 return -1; 249 return 0; 250 } 251 252 /* Write data to memory BIO */ 253 254 if (BIO_write(rctx->mem, rctx->iobuf, n) != n) 255 return 0; 256 } 257 258 switch(rctx->state) 259 { 260 261 case OHS_ASN1_WRITE: 262 n = BIO_get_mem_data(rctx->mem, &p); 263 264 i = BIO_write(rctx->io, 265 p + (n - rctx->asn1_len), rctx->asn1_len); 266 267 if (i <= 0) 268 { 269 if (BIO_should_retry(rctx->io)) 270 return -1; 271 rctx->state = OHS_ERROR; 272 return 0; 273 } 274 275 rctx->asn1_len -= i; 276 277 if (rctx->asn1_len > 0) 278 goto next_io; 279 280 rctx->state = OHS_ASN1_FLUSH; 281 282 (void)BIO_reset(rctx->mem); 283 284 case OHS_ASN1_FLUSH: 285 286 i = BIO_flush(rctx->io); 287 288 if (i > 0) 289 { 290 rctx->state = OHS_FIRSTLINE; 291 goto next_io; 292 } 293 294 if (BIO_should_retry(rctx->io)) 295 return -1; 296 297 rctx->state = OHS_ERROR; 298 return 0; 299 300 case OHS_ERROR: 301 return 0; 302 303 case OHS_FIRSTLINE: 304 case OHS_HEADERS: 305 306 /* Attempt to read a line in */ 307 308 next_line: 309 /* Due to &%^*$" memory BIO behaviour with BIO_gets we 310 * have to check there's a complete line in there before 311 * calling BIO_gets or we'll just get a partial read. 312 */ 313 n = BIO_get_mem_data(rctx->mem, &p); 314 if ((n <= 0) || !memchr(p, '\n', n)) 315 { 316 if (n >= rctx->iobuflen) 317 { 318 rctx->state = OHS_ERROR; 319 return 0; 320 } 321 goto next_io; 322 } 323 n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen); 324 325 if (n <= 0) 326 { 327 if (BIO_should_retry(rctx->mem)) 328 goto next_io; 329 rctx->state = OHS_ERROR; 330 return 0; 331 } 332 333 /* Don't allow excessive lines */ 334 if (n == rctx->iobuflen) 335 { 336 rctx->state = OHS_ERROR; 337 return 0; 338 } 339 340 /* First line */ 341 if (rctx->state == OHS_FIRSTLINE) 342 { 343 if (parse_http_line1((char *)rctx->iobuf)) 344 { 345 rctx->state = OHS_HEADERS; 346 goto next_line; 347 } 348 else 349 { 350 rctx->state = OHS_ERROR; 351 return 0; 352 } 353 } 354 else 355 { 356 /* Look for blank line: end of headers */ 357 for (p = rctx->iobuf; *p; p++) 358 { 359 if ((*p != '\r') && (*p != '\n')) 360 break; 361 } 362 if (*p) 363 goto next_line; 364 365 rctx->state = OHS_ASN1_HEADER; 366 367 } 368 369 /* Fall thru */ 370 371 372 case OHS_ASN1_HEADER: 373 /* Now reading ASN1 header: can read at least 6 bytes which 374 * is more than enough for any valid ASN1 SEQUENCE header 375 */ 376 n = BIO_get_mem_data(rctx->mem, &p); 377 if (n < 6) 378 goto next_io; 379 380 /* Check it is an ASN1 SEQUENCE */ 381 if (*p++ != (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED)) 382 { 383 rctx->state = OHS_ERROR; 384 return 0; 385 } 386 387 /* Check out length field */ 388 if (*p & 0x80) 389 { 390 n = *p & 0x7F; 391 /* Not NDEF or excessive length */ 392 if (!n || (n > 4)) 393 { 394 rctx->state = OHS_ERROR; 395 return 0; 396 } 397 p++; 398 rctx->asn1_len = 0; 399 for (i = 0; i < n; i++) 400 { 401 rctx->asn1_len <<= 8; 402 rctx->asn1_len |= *p++; 403 } 404 405 if (rctx->asn1_len > OCSP_MAX_REQUEST_LENGTH) 406 { 407 rctx->state = OHS_ERROR; 408 return 0; 409 } 410 411 rctx->asn1_len += n + 2; 412 } 413 else 414 rctx->asn1_len = *p + 2; 415 416 rctx->state = OHS_ASN1_CONTENT; 417 418 /* Fall thru */ 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; 424 425 426 *presp = d2i_OCSP_RESPONSE(NULL, &p, rctx->asn1_len); 427 if (*presp) 428 { 429 rctx->state = OHS_DONE; 430 return 1; 431 } 432 433 rctx->state = OHS_ERROR; 434 return 0; 435 436 break; 437 438 case OHS_DONE: 439 return 1; 440 441 } 442 443 444 445 return 0; 446 447 448 } 449 450 /* Blocking OCSP request handler: now a special case of non-blocking I/O */ 451 452 OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req) 453 { 454 OCSP_RESPONSE *resp = NULL; 455 OCSP_REQ_CTX *ctx; 456 int rv; 457 458 ctx = OCSP_sendreq_new(b, path, req, -1); 459 460 do 461 { 462 rv = OCSP_sendreq_nbio(&resp, ctx); 463 } while ((rv == -1) && BIO_should_retry(b)); 464 465 OCSP_REQ_CTX_free(ctx); 466 467 if (rv) 468 return resp; 469 470 return NULL; 471 } 472