ssl/bio_ssl.c

   1 /*
   2  * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <errno.h>
  14 #include <openssl/crypto.h>
  15 #include "internal/bio.h"
  16 #include <openssl/err.h>
  17 #include "ssl_local.h"
  18
  19 static int ssl_write(BIO *h, const char *buf, size_t size, size_t *written);
  20 static int ssl_read(BIO *b, char *buf, size_t size, size_t *readbytes);
  21 static int ssl_puts(BIO *h, const char *str);
  22 static long ssl_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  23 static int ssl_new(BIO *h);
  24 static int ssl_free(BIO *data);
  25 static long ssl_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp);
  26 typedef struct bio_ssl_st {
  27     SSL *ssl;                   /* The ssl handle :-) */
  28     /* re-negotiate every time the total number of bytes is this size */
  29     int num_renegotiates;
  30     unsigned long renegotiate_count;
  31     size_t byte_count;
  32     unsigned long renegotiate_timeout;
  33     unsigned long last_time;
  34 } BIO_SSL;
  35
  36 static const BIO_METHOD methods_sslp = {
  37     BIO_TYPE_SSL,
  38     "ssl",
  39     ssl_write,
  40     NULL,                       /* ssl_write_old, */
  41     ssl_read,
  42     NULL,                       /* ssl_read_old,  */
  43     ssl_puts,
  44     NULL,                       /* ssl_gets,      */
  45     ssl_ctrl,
  46     ssl_new,
  47     ssl_free,
  48     ssl_callback_ctrl,
  49 };
  50
  51 const BIO_METHOD *BIO_f_ssl(void)
  52 {
  53     return &methods_sslp;
  54 }
  55
  56 static int ssl_new(BIO *bi)
  57 {
  58     BIO_SSL *bs = OPENSSL_zalloc(sizeof(*bs));
  59
  60     if (bs == NULL) {
  61         ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
  62         return 0;
  63     }
  64     BIO_set_init(bi, 0);
  65     BIO_set_data(bi, bs);
  66     /* Clear all flags */
  67     BIO_clear_flags(bi, ~0);
  68
  69     return 1;
  70 }
  71
  72 static int ssl_free(BIO *a)
  73 {
  74     BIO_SSL *bs;
  75
  76     if (a == NULL)
  77         return 0;
  78     bs = BIO_get_data(a);
  79     if (BIO_get_shutdown(a)) {
  80         if (bs->ssl != NULL)
  81             SSL_shutdown(bs->ssl);
  82         if (BIO_get_init(a))
  83             SSL_free(bs->ssl);
  84         BIO_clear_flags(a, ~0); /* Clear all flags */
  85         BIO_set_init(a, 0);
  86     }
  87     OPENSSL_free(bs);
  88     return 1;
  89 }
  90
  91 static int ssl_read(BIO *b, char *buf, size_t size, size_t *readbytes)
  92 {
  93     int ret = 1;
  94     BIO_SSL *sb;
  95     SSL *ssl;
  96     int retry_reason = 0;
  97     int r = 0;
  98
  99     if (buf == NULL)
 100         return 0;
 101     sb = BIO_get_data(b);
 102     ssl = sb->ssl;
 103
 104     BIO_clear_retry_flags(b);
 105
 106     ret = ssl_read_internal(ssl, buf, size, readbytes);
 107
 108     switch (SSL_get_error(ssl, ret)) {
 109     case SSL_ERROR_NONE:
 110         if (sb->renegotiate_count > 0) {
 111             sb->byte_count += *readbytes;
 112             if (sb->byte_count > sb->renegotiate_count) {
 113                 sb->byte_count = 0;
 114                 sb->num_renegotiates++;
 115                 SSL_renegotiate(ssl);
 116                 r = 1;
 117             }
 118         }
 119         if ((sb->renegotiate_timeout > 0) && (!r)) {
 120             unsigned long tm;
 121
 122             tm = (unsigned long)time(NULL);
 123             if (tm > sb->last_time + sb->renegotiate_timeout) {
 124                 sb->last_time = tm;
 125                 sb->num_renegotiates++;
 126                 SSL_renegotiate(ssl);
 127             }
 128         }
 129
 130         break;
 131     case SSL_ERROR_WANT_READ:
 132         BIO_set_retry_read(b);
 133         break;
 134     case SSL_ERROR_WANT_WRITE:
 135         BIO_set_retry_write(b);
 136         break;
 137     case SSL_ERROR_WANT_X509_LOOKUP:
 138         BIO_set_retry_special(b);
 139         retry_reason = BIO_RR_SSL_X509_LOOKUP;
 140         break;
 141     case SSL_ERROR_WANT_ACCEPT:
 142         BIO_set_retry_special(b);
 143         retry_reason = BIO_RR_ACCEPT;
 144         break;
 145     case SSL_ERROR_WANT_CONNECT:
 146         BIO_set_retry_special(b);
 147         retry_reason = BIO_RR_CONNECT;
 148         break;
 149     case SSL_ERROR_SYSCALL:
 150     case SSL_ERROR_SSL:
 151     case SSL_ERROR_ZERO_RETURN:
 152     default:
 153         break;
 154     }
 155
 156     BIO_set_retry_reason(b, retry_reason);
 157
 158     return ret;
 159 }
 160
 161 static int ssl_write(BIO *b, const char *buf, size_t size, size_t *written)
 162 {
 163     int ret, r = 0;
 164     int retry_reason = 0;
 165     SSL *ssl;
 166     BIO_SSL *bs;
 167
 168     if (buf == NULL)
 169         return 0;
 170     bs = BIO_get_data(b);
 171     ssl = bs->ssl;
 172
 173     BIO_clear_retry_flags(b);
 174
 175     ret = ssl_write_internal(ssl, buf, size, written);
 176
 177     switch (SSL_get_error(ssl, ret)) {
 178     case SSL_ERROR_NONE:
 179         if (bs->renegotiate_count > 0) {
 180             bs->byte_count += *written;
 181             if (bs->byte_count > bs->renegotiate_count) {
 182                 bs->byte_count = 0;
 183                 bs->num_renegotiates++;
 184                 SSL_renegotiate(ssl);
 185                 r = 1;
 186             }
 187         }
 188         if ((bs->renegotiate_timeout > 0) && (!r)) {
 189             unsigned long tm;
 190
 191             tm = (unsigned long)time(NULL);
 192             if (tm > bs->last_time + bs->renegotiate_timeout) {
 193                 bs->last_time = tm;
 194                 bs->num_renegotiates++;
 195                 SSL_renegotiate(ssl);
 196             }
 197         }
 198         break;
 199     case SSL_ERROR_WANT_WRITE:
 200         BIO_set_retry_write(b);
 201         break;
 202     case SSL_ERROR_WANT_READ:
 203         BIO_set_retry_read(b);
 204         break;
 205     case SSL_ERROR_WANT_X509_LOOKUP:
 206         BIO_set_retry_special(b);
 207         retry_reason = BIO_RR_SSL_X509_LOOKUP;
 208         break;
 209     case SSL_ERROR_WANT_CONNECT:
 210         BIO_set_retry_special(b);
 211         retry_reason = BIO_RR_CONNECT;
 212     case SSL_ERROR_SYSCALL:
 213     case SSL_ERROR_SSL:
 214     default:
 215         break;
 216     }
 217
 218     BIO_set_retry_reason(b, retry_reason);
 219
 220     return ret;
 221 }
 222
 223 static long ssl_ctrl(BIO *b, int cmd, long num, void *ptr)
 224 {
 225     SSL **sslp, *ssl;
 226     BIO_SSL *bs, *dbs;
 227     BIO *dbio, *bio;
 228     long ret = 1;
 229     BIO *next;
 230     SSL_CONNECTION *sc = NULL;
 231
 232     bs = BIO_get_data(b);
 233     next = BIO_next(b);
 234     ssl = bs->ssl;
 235     if ((ssl == NULL
 236          || (sc = SSL_CONNECTION_FROM_SSL(ssl)) == NULL)
 237         && cmd != BIO_C_SET_SSL)
 238         return 0;
 239     /* TODO(QUIC): The rbio/wbio might be from QUIC_CONNECTION instead */
 240     switch (cmd) {
 241     case BIO_CTRL_RESET:
 242         SSL_shutdown(ssl);
 243
 244         if (sc->handshake_func == ssl->method->ssl_connect)
 245             SSL_set_connect_state(ssl);
 246         else if (sc->handshake_func == ssl->method->ssl_accept)
 247             SSL_set_accept_state(ssl);
 248
 249         if (!SSL_clear(ssl)) {
 250             ret = 0;
 251             break;
 252         }
 253
 254         if (next != NULL)
 255             ret = BIO_ctrl(next, cmd, num, ptr);
 256         else if (sc->rbio != NULL)
 257             ret = BIO_ctrl(sc->rbio, cmd, num, ptr);
 258         else
 259             ret = 1;
 260         break;
 261     case BIO_CTRL_INFO:
 262         ret = 0;
 263         break;
 264     case BIO_C_SSL_MODE:
 265         if (num)                /* client mode */
 266             SSL_set_connect_state(ssl);
 267         else
 268             SSL_set_accept_state(ssl);
 269         break;
 270     case BIO_C_SET_SSL_RENEGOTIATE_TIMEOUT:
 271         ret = bs->renegotiate_timeout;
 272         if (num < 60)
 273             num = 5;
 274         bs->renegotiate_timeout = (unsigned long)num;
 275         bs->last_time = (unsigned long)time(NULL);
 276         break;
 277     case BIO_C_SET_SSL_RENEGOTIATE_BYTES:
 278         ret = bs->renegotiate_count;
 279         if ((long)num >= 512)
 280             bs->renegotiate_count = (unsigned long)num;
 281         break;
 282     case BIO_C_GET_SSL_NUM_RENEGOTIATES:
 283         ret = bs->num_renegotiates;
 284         break;
 285     case BIO_C_SET_SSL:
 286         if (ssl != NULL) {
 287             ssl_free(b);
 288             if (!ssl_new(b))
 289                 return 0;
 290             bs = BIO_get_data(b);
 291         }
 292         BIO_set_shutdown(b, num);
 293         ssl = (SSL *)ptr;
 294         bs->ssl = ssl;
 295         bio = SSL_get_rbio(ssl);
 296         if (bio != NULL) {
 297             if (next != NULL)
 298                 BIO_push(bio, next);
 299             BIO_set_next(b, bio);
 300             BIO_up_ref(bio);
 301         }
 302         BIO_set_init(b, 1);
 303         break;
 304     case BIO_C_GET_SSL:
 305         if (ptr != NULL) {
 306             sslp = (SSL **)ptr;
 307             *sslp = ssl;
 308         } else
 309             ret = 0;
 310         break;
 311     case BIO_CTRL_GET_CLOSE:
 312         ret = BIO_get_shutdown(b);
 313         break;
 314     case BIO_CTRL_SET_CLOSE:
 315         BIO_set_shutdown(b, (int)num);
 316         break;
 317     case BIO_CTRL_WPENDING:
 318         ret = BIO_ctrl(sc->wbio, cmd, num, ptr);
 319         break;
 320     case BIO_CTRL_PENDING:
 321         ret = SSL_pending(ssl);
 322         if (ret == 0)
 323             ret = BIO_pending(sc->rbio);
 324         break;
 325     case BIO_CTRL_FLUSH:
 326         BIO_clear_retry_flags(b);
 327         ret = BIO_ctrl(sc->wbio, cmd, num, ptr);
 328         BIO_copy_next_retry(b);
 329         break;
 330     case BIO_CTRL_PUSH:
 331         if ((next != NULL) && (next != sc->rbio)) {
 332             /*
 333              * We are going to pass ownership of next to the SSL object...but
 334              * we don't own a reference to pass yet - so up ref
 335              */
 336             BIO_up_ref(next);
 337             SSL_set_bio(ssl, next, next);
 338         }
 339         break;
 340     case BIO_CTRL_POP:
 341         /* Only detach if we are the BIO explicitly being popped */
 342         if (b == ptr) {
 343             /* This will clear the reference we obtained during push */
 344             SSL_set_bio(ssl, NULL, NULL);
 345         }
 346         break;
 347     case BIO_C_DO_STATE_MACHINE:
 348         BIO_clear_retry_flags(b);
 349
 350         BIO_set_retry_reason(b, 0);
 351         ret = (int)SSL_do_handshake(ssl);
 352
 353         switch (SSL_get_error(ssl, (int)ret)) {
 354         case SSL_ERROR_WANT_READ:
 355             BIO_set_flags(b, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
 356             break;
 357         case SSL_ERROR_WANT_WRITE:
 358             BIO_set_flags(b, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
 359             break;
 360         case SSL_ERROR_WANT_CONNECT:
 361             BIO_set_flags(b, BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY);
 362             BIO_set_retry_reason(b, BIO_get_retry_reason(next));
 363             break;
 364         case SSL_ERROR_WANT_X509_LOOKUP:
 365             BIO_set_retry_special(b);
 366             BIO_set_retry_reason(b, BIO_RR_SSL_X509_LOOKUP);
 367             break;
 368         default:
 369             break;
 370         }
 371         break;
 372     case BIO_CTRL_DUP:
 373         dbio = (BIO *)ptr;
 374         dbs = BIO_get_data(dbio);
 375         SSL_free(dbs->ssl);
 376         dbs->ssl = SSL_dup(ssl);
 377         dbs->num_renegotiates = bs->num_renegotiates;
 378         dbs->renegotiate_count = bs->renegotiate_count;
 379         dbs->byte_count = bs->byte_count;
 380         dbs->renegotiate_timeout = bs->renegotiate_timeout;
 381         dbs->last_time = bs->last_time;
 382         ret = (dbs->ssl != NULL);
 383         break;
 384     case BIO_C_GET_FD:
 385         ret = BIO_ctrl(sc->rbio, cmd, num, ptr);
 386         break;
 387     case BIO_CTRL_SET_CALLBACK:
 388         ret = 0; /* use callback ctrl */
 389         break;
 390     default:
 391         ret = BIO_ctrl(sc->rbio, cmd, num, ptr);
 392         break;
 393     }
 394     return ret;
 395 }
 396
 397 static long ssl_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
 398 {
 399     SSL *ssl;
 400     BIO_SSL *bs;
 401     long ret = 1;
 402
 403     bs = BIO_get_data(b);
 404     ssl = bs->ssl;
 405     switch (cmd) {
 406     case BIO_CTRL_SET_CALLBACK:
 407         ret = BIO_callback_ctrl(SSL_get_rbio(ssl), cmd, fp);
 408         break;
 409     default:
 410         ret = 0;
 411         break;
 412     }
 413     return ret;
 414 }
 415
 416 static int ssl_puts(BIO *bp, const char *str)
 417 {
 418     int n, ret;
 419
 420     n = strlen(str);
 421     ret = BIO_write(bp, str, n);
 422     return ret;
 423 }
 424
 425 BIO *BIO_new_buffer_ssl_connect(SSL_CTX *ctx)
 426 {
 427 #ifndef OPENSSL_NO_SOCK
 428     BIO *ret = NULL, *buf = NULL, *ssl = NULL;
 429
 430     if ((buf = BIO_new(BIO_f_buffer())) == NULL)
 431         return NULL;
 432     if ((ssl = BIO_new_ssl_connect(ctx)) == NULL)
 433         goto err;
 434     if ((ret = BIO_push(buf, ssl)) == NULL)
 435         goto err;
 436     return ret;
 437  err:
 438     BIO_free(buf);
 439     BIO_free(ssl);
 440 #endif
 441     return NULL;
 442 }
 443
 444 BIO *BIO_new_ssl_connect(SSL_CTX *ctx)
 445 {
 446 #ifndef OPENSSL_NO_SOCK
 447     BIO *ret = NULL, *con = NULL, *ssl = NULL;
 448
 449     if ((con = BIO_new(BIO_s_connect())) == NULL)
 450         return NULL;
 451     if ((ssl = BIO_new_ssl(ctx, 1)) == NULL)
 452         goto err;
 453     if ((ret = BIO_push(ssl, con)) == NULL)
 454         goto err;
 455     return ret;
 456  err:
 457     BIO_free(ssl);
 458     BIO_free(con);
 459 #endif
 460     return NULL;
 461 }
 462
 463 BIO *BIO_new_ssl(SSL_CTX *ctx, int client)
 464 {
 465     BIO *ret;
 466     SSL *ssl;
 467
 468     if ((ret = BIO_new(BIO_f_ssl())) == NULL)
 469         return NULL;
 470     if ((ssl = SSL_new(ctx)) == NULL) {
 471         BIO_free(ret);
 472         return NULL;
 473     }
 474     if (client)
 475         SSL_set_connect_state(ssl);
 476     else
 477         SSL_set_accept_state(ssl);
 478
 479     BIO_set_ssl(ret, ssl, BIO_CLOSE);
 480     return ret;
 481 }
 482
 483 int BIO_ssl_copy_session_id(BIO *t, BIO *f)
 484 {
 485     BIO_SSL *tdata, *fdata;
 486     t = BIO_find_type(t, BIO_TYPE_SSL);
 487     f = BIO_find_type(f, BIO_TYPE_SSL);
 488     if ((t == NULL) || (f == NULL))
 489         return 0;
 490     tdata = BIO_get_data(t);
 491     fdata = BIO_get_data(f);
 492     if ((tdata->ssl == NULL) || (fdata->ssl == NULL))
 493         return 0;
 494     if (!SSL_copy_session_id(tdata->ssl, (fdata->ssl)))
 495         return 0;
 496     return 1;
 497 }
 498
 499 void BIO_ssl_shutdown(BIO *b)
 500 {
 501     BIO_SSL *bdata;
 502
 503     for (; b != NULL; b = BIO_next(b)) {
 504         if (BIO_method_type(b) != BIO_TYPE_SSL)
 505             continue;
 506         bdata = BIO_get_data(b);
 507         if (bdata != NULL && bdata->ssl != NULL)
 508             SSL_shutdown(bdata->ssl);
 509     }
 510 }