crypto/ocsp/ocsp_ht.c

   1 /* ocsp_ht.c */
   2 /*
   3  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   4  * 2006.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    licensing@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <ctype.h>
  63 #include <string.h>
  64 #include "e_os.h"
  65 #include <openssl/asn1.h>
  66 #include <openssl/ocsp.h>
  67 #include <openssl/err.h>
  68 #include <openssl/buffer.h>
  69
  70 /* Stateful OCSP request code, supporting non-blocking I/O */
  71
  72 /* Opaque OCSP request status structure */
  73
  74 struct ocsp_req_ctx_st {
  75     int state;                  /* Current I/O state */
  76     unsigned char *iobuf;       /* Line buffer */
  77     int iobuflen;               /* Line buffer length */
  78     BIO *io;                    /* BIO to perform I/O with */
  79     BIO *mem;                   /* Memory BIO response is built into */
  80     unsigned long asn1_len;     /* ASN1 length of response */
  81     unsigned long max_resp_len; /* Maximum length of response */
  82 };
  83
  84 #define OCSP_MAX_RESP_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 /* First call: ready to start I/O */
 102 #define OHS_ASN1_WRITE_INIT     (5 | OHS_NOREAD)
 103 /* Request being sent */
 104 #define OHS_ASN1_WRITE          (6 | OHS_NOREAD)
 105 /* Request being flushed */
 106 #define OHS_ASN1_FLUSH          (7 | OHS_NOREAD)
 107 /* Completed */
 108 #define OHS_DONE                (8 | OHS_NOREAD)
 109 /* Headers set, no final \r\n included */
 110 #define OHS_HTTP_HEADER         (9 | OHS_NOREAD)
 111
 112 static int parse_http_line1(char *line);
 113
 114 OCSP_REQ_CTX *OCSP_REQ_CTX_new(BIO *io, int maxline)
 115 {
 116     OCSP_REQ_CTX *rctx = OPENSSL_malloc(sizeof(*rctx));
 117
 118     if (!rctx)
 119         return NULL;
 120     rctx->state = OHS_ERROR;
 121     rctx->max_resp_len = OCSP_MAX_RESP_LENGTH;
 122     rctx->mem = BIO_new(BIO_s_mem());
 123     rctx->io = io;
 124     rctx->asn1_len = 0;
 125     if (maxline > 0)
 126         rctx->iobuflen = maxline;
 127     else
 128         rctx->iobuflen = OCSP_MAX_LINE_LEN;
 129     rctx->iobuf = OPENSSL_malloc(rctx->iobuflen);
 130     if (!rctx->iobuf || !rctx->mem) {
 131         OCSP_REQ_CTX_free(rctx);
 132         return NULL;
 133     }
 134     return rctx;
 135 }
 136
 137 void OCSP_REQ_CTX_free(OCSP_REQ_CTX *rctx)
 138 {
 139     if (!rctx)
 140         return;
 141     BIO_free(rctx->mem);
 142     OPENSSL_free(rctx->iobuf);
 143     OPENSSL_free(rctx);
 144 }
 145
 146 BIO *OCSP_REQ_CTX_get0_mem_bio(OCSP_REQ_CTX *rctx)
 147 {
 148     return rctx->mem;
 149 }
 150
 151 void OCSP_set_max_response_length(OCSP_REQ_CTX *rctx, unsigned long len)
 152 {
 153     if (len == 0)
 154         rctx->max_resp_len = OCSP_MAX_RESP_LENGTH;
 155     else
 156         rctx->max_resp_len = len;
 157 }
 158
 159 int OCSP_REQ_CTX_i2d(OCSP_REQ_CTX *rctx, const ASN1_ITEM *it, ASN1_VALUE *val)
 160 {
 161     static const char req_hdr[] =
 162         "Content-Type: application/ocsp-request\r\n"
 163         "Content-Length: %d\r\n\r\n";
 164     int reqlen = ASN1_item_i2d(val, NULL, it);
 165     if (BIO_printf(rctx->mem, req_hdr, reqlen) <= 0)
 166         return 0;
 167     if (ASN1_item_i2d_bio(it, rctx->mem, val) <= 0)
 168         return 0;
 169     rctx->state = OHS_ASN1_WRITE_INIT;
 170     return 1;
 171 }
 172
 173 int OCSP_REQ_CTX_nbio_d2i(OCSP_REQ_CTX *rctx,
 174                           ASN1_VALUE **pval, const ASN1_ITEM *it)
 175 {
 176     int rv, len;
 177     const unsigned char *p;
 178
 179     rv = OCSP_REQ_CTX_nbio(rctx);
 180     if (rv != 1)
 181         return rv;
 182
 183     len = BIO_get_mem_data(rctx->mem, &p);
 184     *pval = ASN1_item_d2i(NULL, &p, len, it);
 185     if (*pval == NULL) {
 186         rctx->state = OHS_ERROR;
 187         return 0;
 188     }
 189     return 1;
 190 }
 191
 192 int OCSP_REQ_CTX_http(OCSP_REQ_CTX *rctx, const char *op, const char *path)
 193 {
 194     static const char http_hdr[] = "%s %s HTTP/1.0\r\n";
 195
 196     if (!path)
 197         path = "/";
 198
 199     if (BIO_printf(rctx->mem, http_hdr, op, path) <= 0)
 200         return 0;
 201     rctx->state = OHS_HTTP_HEADER;
 202     return 1;
 203 }
 204
 205 int OCSP_REQ_CTX_set1_req(OCSP_REQ_CTX *rctx, OCSP_REQUEST *req)
 206 {
 207     return OCSP_REQ_CTX_i2d(rctx, ASN1_ITEM_rptr(OCSP_REQUEST),
 208                             (ASN1_VALUE *)req);
 209 }
 210
 211 int OCSP_REQ_CTX_add1_header(OCSP_REQ_CTX *rctx,
 212                              const char *name, const char *value)
 213 {
 214     if (!name)
 215         return 0;
 216     if (BIO_puts(rctx->mem, name) <= 0)
 217         return 0;
 218     if (value) {
 219         if (BIO_write(rctx->mem, ": ", 2) != 2)
 220             return 0;
 221         if (BIO_puts(rctx->mem, value) <= 0)
 222             return 0;
 223     }
 224     if (BIO_write(rctx->mem, "\r\n", 2) != 2)
 225         return 0;
 226     rctx->state = OHS_HTTP_HEADER;
 227     return 1;
 228 }
 229
 230 OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, const char *path, OCSP_REQUEST *req,
 231                                int maxline)
 232 {
 233
 234     OCSP_REQ_CTX *rctx = NULL;
 235     rctx = OCSP_REQ_CTX_new(io, maxline);
 236     if (!rctx)
 237         return NULL;
 238
 239     if (!OCSP_REQ_CTX_http(rctx, "POST", path))
 240         goto err;
 241
 242     if (req && !OCSP_REQ_CTX_set1_req(rctx, req))
 243         goto err;
 244
 245     return rctx;
 246
 247  err:
 248     OCSP_REQ_CTX_free(rctx);
 249     return NULL;
 250 }
 251
 252 /*
 253  * Parse the HTTP response. This will look like this: "HTTP/1.0 200 OK". We
 254  * need to obtain the numeric code and (optional) informational message.
 255  */
 256
 257 static int parse_http_line1(char *line)
 258 {
 259     int retcode;
 260     char *p, *q, *r;
 261     /* Skip to first white space (passed protocol info) */
 262
 263     for (p = line; *p && !isspace((unsigned char)*p); p++)
 264         continue;
 265     if (!*p) {
 266         OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
 267         return 0;
 268     }
 269
 270     /* Skip past white space to start of response code */
 271     while (*p && isspace((unsigned char)*p))
 272         p++;
 273
 274     if (!*p) {
 275         OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
 276         return 0;
 277     }
 278
 279     /* Find end of response code: first whitespace after start of code */
 280     for (q = p; *q && !isspace((unsigned char)*q); q++)
 281         continue;
 282
 283     if (!*q) {
 284         OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
 285         return 0;
 286     }
 287
 288     /* Set end of response code and start of message */
 289     *q++ = 0;
 290
 291     /* Attempt to parse numeric code */
 292     retcode = strtoul(p, &r, 10);
 293
 294     if (*r)
 295         return 0;
 296
 297     /* Skip over any leading white space in message */
 298     while (*q && isspace((unsigned char)*q))
 299         q++;
 300
 301     if (*q) {
 302         /*
 303          * Finally zap any trailing white space in message (include CRLF)
 304          */
 305
 306         /* We know q has a non white space character so this is OK */
 307         for (r = q + strlen(q) - 1; isspace((unsigned char)*r); r--)
 308             *r = 0;
 309     }
 310     if (retcode != 200) {
 311         OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR);
 312         if (!*q)
 313             ERR_add_error_data(2, "Code=", p);
 314         else
 315             ERR_add_error_data(4, "Code=", p, ",Reason=", q);
 316         return 0;
 317     }
 318
 319     return 1;
 320
 321 }
 322
 323 int OCSP_REQ_CTX_nbio(OCSP_REQ_CTX *rctx)
 324 {
 325     int i, n;
 326     const unsigned char *p;
 327  next_io:
 328     if (!(rctx->state & OHS_NOREAD)) {
 329         n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen);
 330
 331         if (n <= 0) {
 332             if (BIO_should_retry(rctx->io))
 333                 return -1;
 334             return 0;
 335         }
 336
 337         /* Write data to memory BIO */
 338
 339         if (BIO_write(rctx->mem, rctx->iobuf, n) != n)
 340             return 0;
 341     }
 342
 343     switch (rctx->state) {
 344     case OHS_HTTP_HEADER:
 345         /* Last operation was adding headers: need a final \r\n */
 346         if (BIO_write(rctx->mem, "\r\n", 2) != 2) {
 347             rctx->state = OHS_ERROR;
 348             return 0;
 349         }
 350         rctx->state = OHS_ASN1_WRITE_INIT;
 351
 352     case OHS_ASN1_WRITE_INIT:
 353         rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL);
 354         rctx->state = OHS_ASN1_WRITE;
 355
 356     case OHS_ASN1_WRITE:
 357         n = BIO_get_mem_data(rctx->mem, &p);
 358
 359         i = BIO_write(rctx->io, p + (n - rctx->asn1_len), rctx->asn1_len);
 360
 361         if (i <= 0) {
 362             if (BIO_should_retry(rctx->io))
 363                 return -1;
 364             rctx->state = OHS_ERROR;
 365             return 0;
 366         }
 367
 368         rctx->asn1_len -= i;
 369
 370         if (rctx->asn1_len > 0)
 371             goto next_io;
 372
 373         rctx->state = OHS_ASN1_FLUSH;
 374
 375         (void)BIO_reset(rctx->mem);
 376
 377     case OHS_ASN1_FLUSH:
 378
 379         i = BIO_flush(rctx->io);
 380
 381         if (i > 0) {
 382             rctx->state = OHS_FIRSTLINE;
 383             goto next_io;
 384         }
 385
 386         if (BIO_should_retry(rctx->io))
 387             return -1;
 388
 389         rctx->state = OHS_ERROR;
 390         return 0;
 391
 392     case OHS_ERROR:
 393         return 0;
 394
 395     case OHS_FIRSTLINE:
 396     case OHS_HEADERS:
 397
 398         /* Attempt to read a line in */
 399
 400  next_line:
 401         /*
 402          * Due to &%^*$" memory BIO behaviour with BIO_gets we have to check
 403          * there's a complete line in there before calling BIO_gets or we'll
 404          * just get a partial read.
 405          */
 406         n = BIO_get_mem_data(rctx->mem, &p);
 407         if ((n <= 0) || !memchr(p, '\n', n)) {
 408             if (n >= rctx->iobuflen) {
 409                 rctx->state = OHS_ERROR;
 410                 return 0;
 411             }
 412             goto next_io;
 413         }
 414         n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen);
 415
 416         if (n <= 0) {
 417             if (BIO_should_retry(rctx->mem))
 418                 goto next_io;
 419             rctx->state = OHS_ERROR;
 420             return 0;
 421         }
 422
 423         /* Don't allow excessive lines */
 424         if (n == rctx->iobuflen) {
 425             rctx->state = OHS_ERROR;
 426             return 0;
 427         }
 428
 429         /* First line */
 430         if (rctx->state == OHS_FIRSTLINE) {
 431             if (parse_http_line1((char *)rctx->iobuf)) {
 432                 rctx->state = OHS_HEADERS;
 433                 goto next_line;
 434             } else {
 435                 rctx->state = OHS_ERROR;
 436                 return 0;
 437             }
 438         } else {
 439             /* Look for blank line: end of headers */
 440             for (p = rctx->iobuf; *p; p++) {
 441                 if ((*p != '\r') && (*p != '\n'))
 442                     break;
 443             }
 444             if (*p)
 445                 goto next_line;
 446
 447             rctx->state = OHS_ASN1_HEADER;
 448
 449         }
 450
 451         /* Fall thru */
 452
 453     case OHS_ASN1_HEADER:
 454         /*
 455          * Now reading ASN1 header: can read at least 2 bytes which is enough
 456          * for ASN1 SEQUENCE header and either length field or at least the
 457          * length of the length field.
 458          */
 459         n = BIO_get_mem_data(rctx->mem, &p);
 460         if (n < 2)
 461             goto next_io;
 462
 463         /* Check it is an ASN1 SEQUENCE */
 464         if (*p++ != (V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)) {
 465             rctx->state = OHS_ERROR;
 466             return 0;
 467         }
 468
 469         /* Check out length field */
 470         if (*p & 0x80) {
 471             /*
 472              * If MSB set on initial length octet we can now always read 6
 473              * octets: make sure we have them.
 474              */
 475             if (n < 6)
 476                 goto next_io;
 477             n = *p & 0x7F;
 478             /* Not NDEF or excessive length */
 479             if (!n || (n > 4)) {
 480                 rctx->state = OHS_ERROR;
 481                 return 0;
 482             }
 483             p++;
 484             rctx->asn1_len = 0;
 485             for (i = 0; i < n; i++) {
 486                 rctx->asn1_len <<= 8;
 487                 rctx->asn1_len |= *p++;
 488             }
 489
 490             if (rctx->asn1_len > rctx->max_resp_len) {
 491                 rctx->state = OHS_ERROR;
 492                 return 0;
 493             }
 494
 495             rctx->asn1_len += n + 2;
 496         } else
 497             rctx->asn1_len = *p + 2;
 498
 499         rctx->state = OHS_ASN1_CONTENT;
 500
 501         /* Fall thru */
 502
 503     case OHS_ASN1_CONTENT:
 504         n = BIO_get_mem_data(rctx->mem, NULL);
 505         if (n < (int)rctx->asn1_len)
 506             goto next_io;
 507
 508         rctx->state = OHS_DONE;
 509         return 1;
 510
 511     case OHS_DONE:
 512         return 1;
 513
 514     }
 515
 516     return 0;
 517
 518 }
 519
 520 int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx)
 521 {
 522     return OCSP_REQ_CTX_nbio_d2i(rctx,
 523                                  (ASN1_VALUE **)presp,
 524                                  ASN1_ITEM_rptr(OCSP_RESPONSE));
 525 }
 526
 527 /* Blocking OCSP request handler: now a special case of non-blocking I/O */
 528
 529 OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, const char *path, OCSP_REQUEST *req)
 530 {
 531     OCSP_RESPONSE *resp = NULL;
 532     OCSP_REQ_CTX *ctx;
 533     int rv;
 534
 535     ctx = OCSP_sendreq_new(b, path, req, -1);
 536
 537     if (!ctx)
 538         return NULL;
 539
 540     do {
 541         rv = OCSP_sendreq_nbio(&resp, ctx);
 542     } while ((rv == -1) && BIO_should_retry(b));
 543
 544     OCSP_REQ_CTX_free(ctx);
 545
 546     if (rv)
 547         return resp;
 548
 549     return NULL;
 550 }