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         return 0;
  62     BIO_set_init(bi, 0);
  63     BIO_set_data(bi, bs);
  64     /* Clear all flags */
  65     BIO_clear_flags(bi, ~0);
  66
  67     return 1;
  68 }
  69
  70 static int ssl_free(BIO *a)
  71 {
  72     BIO_SSL *bs;
  73
  74     if (a == NULL)
  75         return 0;
  76     bs = BIO_get_data(a);
  77     if (BIO_get_shutdown(a)) {
  78         if (bs->ssl != NULL)
  79             SSL_shutdown(bs->ssl);
  80         if (BIO_get_init(a))
  81             SSL_free(bs->ssl);
  82         BIO_clear_flags(a, ~0); /* Clear all flags */
  83         BIO_set_init(a, 0);
  84     }
  85     OPENSSL_free(bs);
  86     return 1;
  87 }
  88
  89 static int ssl_read(BIO *b, char *buf, size_t size, size_t *readbytes)
  90 {
  91     int ret = 1;
  92     BIO_SSL *sb;
  93     SSL *ssl;
  94     int retry_reason = 0;
  95     int r = 0;
  96
  97     if (buf == NULL)
  98         return 0;
  99     sb = BIO_get_data(b);
 100     ssl = sb->ssl;
 101
 102     BIO_clear_retry_flags(b);
 103
 104     ret = ssl_read_internal(ssl, buf, size, readbytes);
 105
 106     switch (SSL_get_error(ssl, ret)) {
 107     case SSL_ERROR_NONE:
 108         if (sb->renegotiate_count > 0) {
 109             sb->byte_count += *readbytes;
 110             if (sb->byte_count > sb->renegotiate_count) {
 111                 sb->byte_count = 0;
 112                 sb->num_renegotiates++;
 113                 SSL_renegotiate(ssl);
 114                 r = 1;
 115             }
 116         }
 117         if ((sb->renegotiate_timeout > 0) && (!r)) {
 118             unsigned long tm;
 119
 120             tm = (unsigned long)time(NULL);
 121             if (tm > sb->last_time + sb->renegotiate_timeout) {
 122                 sb->last_time = tm;
 123                 sb->num_renegotiates++;
 124                 SSL_renegotiate(ssl);
 125             }
 126         }
 127
 128         break;
 129     case SSL_ERROR_WANT_READ:
 130         BIO_set_retry_read(b);
 131         break;
 132     case SSL_ERROR_WANT_WRITE:
 133         BIO_set_retry_write(b);
 134         break;
 135     case SSL_ERROR_WANT_X509_LOOKUP:
 136         BIO_set_retry_special(b);
 137         retry_reason = BIO_RR_SSL_X509_LOOKUP;
 138         break;
 139     case SSL_ERROR_WANT_ACCEPT:
 140         BIO_set_retry_special(b);
 141         retry_reason = BIO_RR_ACCEPT;
 142         break;
 143     case SSL_ERROR_WANT_CONNECT:
 144         BIO_set_retry_special(b);
 145         retry_reason = BIO_RR_CONNECT;
 146         break;
 147     case SSL_ERROR_SYSCALL:
 148     case SSL_ERROR_SSL:
 149     case SSL_ERROR_ZERO_RETURN:
 150     default:
 151         break;
 152     }
 153
 154     BIO_set_retry_reason(b, retry_reason);
 155
 156     return ret;
 157 }
 158
 159 static int ssl_write(BIO *b, const char *buf, size_t size, size_t *written)
 160 {
 161     int ret, r = 0;
 162     int retry_reason = 0;
 163     SSL *ssl;
 164     BIO_SSL *bs;
 165
 166     if (buf == NULL)
 167         return 0;
 168     bs = BIO_get_data(b);
 169     ssl = bs->ssl;
 170
 171     BIO_clear_retry_flags(b);
 172
 173     ret = ssl_write_internal(ssl, buf, size, written);
 174
 175     switch (SSL_get_error(ssl, ret)) {
 176     case SSL_ERROR_NONE:
 177         if (bs->renegotiate_count > 0) {
 178             bs->byte_count += *written;
 179             if (bs->byte_count > bs->renegotiate_count) {
 180                 bs->byte_count = 0;
 181                 bs->num_renegotiates++;
 182                 SSL_renegotiate(ssl);
 183                 r = 1;
 184             }
 185         }
 186         if ((bs->renegotiate_timeout > 0) && (!r)) {
 187             unsigned long tm;
 188
 189             tm = (unsigned long)time(NULL);
 190             if (tm > bs->last_time + bs->renegotiate_timeout) {
 191                 bs->last_time = tm;
 192                 bs->num_renegotiates++;
 193                 SSL_renegotiate(ssl);
 194             }
 195         }
 196         break;
 197     case SSL_ERROR_WANT_WRITE:
 198         BIO_set_retry_write(b);
 199         break;
 200     case SSL_ERROR_WANT_READ:
 201         BIO_set_retry_read(b);
 202         break;
 203     case SSL_ERROR_WANT_X509_LOOKUP:
 204         BIO_set_retry_special(b);
 205         retry_reason = BIO_RR_SSL_X509_LOOKUP;
 206         break;
 207     case SSL_ERROR_WANT_CONNECT:
 208         BIO_set_retry_special(b);
 209         retry_reason = BIO_RR_CONNECT;
 210     case SSL_ERROR_SYSCALL:
 211     case SSL_ERROR_SSL:
 212     default:
 213         break;
 214     }
 215
 216     BIO_set_retry_reason(b, retry_reason);
 217
 218     return ret;
 219 }
 220
 221 static long ssl_ctrl(BIO *b, int cmd, long num, void *ptr)
 222 {
 223     SSL **sslp, *ssl;
 224     BIO_SSL *bs, *dbs;
 225     BIO *dbio, *bio;
 226     long ret = 1;
 227     BIO *next;
 228     SSL_CONNECTION *sc = NULL;
 229
 230     bs = BIO_get_data(b);
 231     next = BIO_next(b);
 232     ssl = bs->ssl;
 233     if ((ssl == NULL
 234          || (sc = SSL_CONNECTION_FROM_SSL(ssl)) == NULL)
 235         && cmd != BIO_C_SET_SSL)
 236         return 0;
 237     /* TODO(QUIC): The rbio/wbio might be from QUIC_CONNECTION instead */
 238     switch (cmd) {
 239     case BIO_CTRL_RESET:
 240         SSL_shutdown(ssl);
 241
 242         if (sc->handshake_func == ssl->method->ssl_connect)
 243             SSL_set_connect_state(ssl);
 244         else if (sc->handshake_func == ssl->method->ssl_accept)
 245             SSL_set_accept_state(ssl);
 246
 247         if (!SSL_clear(ssl)) {
 248             ret = 0;
 249             break;
 250         }
 251
 252         if (next != NULL)
 253             ret = BIO_ctrl(next, cmd, num, ptr);
 254         else if (sc->rbio != NULL)
 255             ret = BIO_ctrl(sc->rbio, cmd, num, ptr);
 256         else
 257             ret = 1;
 258         break;
 259     case BIO_CTRL_INFO:
 260         ret = 0;
 261         break;
 262     case BIO_C_SSL_MODE:
 263         if (num)                /* client mode */
 264             SSL_set_connect_state(ssl);
 265         else
 266             SSL_set_accept_state(ssl);
 267         break;
 268     case BIO_C_SET_SSL_RENEGOTIATE_TIMEOUT:
 269         ret = bs->renegotiate_timeout;
 270         if (num < 60)
 271             num = 5;
 272         bs->renegotiate_timeout = (unsigned long)num;
 273         bs->last_time = (unsigned long)time(NULL);
 274         break;
 275     case BIO_C_SET_SSL_RENEGOTIATE_BYTES:
 276         ret = bs->renegotiate_count;
 277         if ((long)num >= 512)
 278             bs->renegotiate_count = (unsigned long)num;
 279         break;
 280     case BIO_C_GET_SSL_NUM_RENEGOTIATES:
 281         ret = bs->num_renegotiates;
 282         break;
 283     case BIO_C_SET_SSL:
 284         if (ssl != NULL) {
 285             ssl_free(b);
 286             if (!ssl_new(b))
 287                 return 0;
 288             bs = BIO_get_data(b);
 289         }
 290         BIO_set_shutdown(b, num);
 291         ssl = (SSL *)ptr;
 292         bs->ssl = ssl;
 293         bio = SSL_get_rbio(ssl);
 294         if (bio != NULL) {
 295             if (next != NULL)
 296                 BIO_push(bio, next);
 297             BIO_set_next(b, bio);
 298             BIO_up_ref(bio);
 299         }
 300         BIO_set_init(b, 1);
 301         break;
 302     case BIO_C_GET_SSL:
 303         if (ptr != NULL) {
 304             sslp = (SSL **)ptr;
 305             *sslp = ssl;
 306         } else
 307             ret = 0;
 308         break;
 309     case BIO_CTRL_GET_CLOSE:
 310         ret = BIO_get_shutdown(b);
 311         break;
 312     case BIO_CTRL_SET_CLOSE:
 313         BIO_set_shutdown(b, (int)num);
 314         break;
 315     case BIO_CTRL_WPENDING:
 316         ret = BIO_ctrl(sc->wbio, cmd, num, ptr);
 317         break;
 318     case BIO_CTRL_PENDING:
 319         ret = SSL_pending(ssl);
 320         if (ret == 0)
 321             ret = BIO_pending(sc->rbio);
 322         break;
 323     case BIO_CTRL_FLUSH:
 324         BIO_clear_retry_flags(b);
 325         ret = BIO_ctrl(sc->wbio, cmd, num, ptr);
 326         BIO_copy_next_retry(b);
 327         break;
 328     case BIO_CTRL_PUSH:
 329         if ((next != NULL) && (next != sc->rbio)) {
 330             /*
 331              * We are going to pass ownership of next to the SSL object...but
 332              * we don't own a reference to pass yet - so up ref
 333              */
 334             BIO_up_ref(next);
 335             SSL_set_bio(ssl, next, next);
 336         }
 337         break;
 338     case BIO_CTRL_POP:
 339         /* Only detach if we are the BIO explicitly being popped */
 340         if (b == ptr) {
 341             /* This will clear the reference we obtained during push */
 342             SSL_set_bio(ssl, NULL, NULL);
 343         }
 344         break;
 345     case BIO_C_DO_STATE_MACHINE:
 346         BIO_clear_retry_flags(b);
 347
 348         BIO_set_retry_reason(b, 0);
 349         ret = (int)SSL_do_handshake(ssl);
 350
 351         switch (SSL_get_error(ssl, (int)ret)) {
 352         case SSL_ERROR_WANT_READ:
 353             BIO_set_flags(b, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
 354             break;
 355         case SSL_ERROR_WANT_WRITE:
 356             BIO_set_flags(b, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
 357             break;
 358         case SSL_ERROR_WANT_CONNECT:
 359             BIO_set_flags(b, BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY);
 360             BIO_set_retry_reason(b, BIO_get_retry_reason(next));
 361             break;
 362         case SSL_ERROR_WANT_X509_LOOKUP:
 363             BIO_set_retry_special(b);
 364             BIO_set_retry_reason(b, BIO_RR_SSL_X509_LOOKUP);
 365             break;
 366         default:
 367             break;
 368         }
 369         break;
 370     case BIO_CTRL_DUP:
 371         dbio = (BIO *)ptr;
 372         dbs = BIO_get_data(dbio);
 373         SSL_free(dbs->ssl);
 374         dbs->ssl = SSL_dup(ssl);
 375         dbs->num_renegotiates = bs->num_renegotiates;
 376         dbs->renegotiate_count = bs->renegotiate_count;
 377         dbs->byte_count = bs->byte_count;
 378         dbs->renegotiate_timeout = bs->renegotiate_timeout;
 379         dbs->last_time = bs->last_time;
 380         ret = (dbs->ssl != NULL);
 381         break;
 382     case BIO_C_GET_FD:
 383         ret = BIO_ctrl(sc->rbio, cmd, num, ptr);
 384         break;
 385     case BIO_CTRL_SET_CALLBACK:
 386         ret = 0; /* use callback ctrl */
 387         break;
 388     case BIO_CTRL_GET_RPOLL_DESCRIPTOR:
 389         if (!SSL_get_rpoll_descriptor(ssl, (BIO_POLL_DESCRIPTOR *)ptr))
 390             ret = 0;
 391         break;
 392     case BIO_CTRL_GET_WPOLL_DESCRIPTOR:
 393         if (!SSL_get_wpoll_descriptor(ssl, (BIO_POLL_DESCRIPTOR *)ptr))
 394             ret = 0;
 395         break;
 396     default:
 397         ret = BIO_ctrl(sc->rbio, cmd, num, ptr);
 398         break;
 399     }
 400     return ret;
 401 }
 402
 403 static long ssl_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
 404 {
 405     SSL *ssl;
 406     BIO_SSL *bs;
 407     long ret = 1;
 408
 409     bs = BIO_get_data(b);
 410     ssl = bs->ssl;
 411     switch (cmd) {
 412     case BIO_CTRL_SET_CALLBACK:
 413         ret = BIO_callback_ctrl(SSL_get_rbio(ssl), cmd, fp);
 414         break;
 415     default:
 416         ret = 0;
 417         break;
 418     }
 419     return ret;
 420 }
 421
 422 static int ssl_puts(BIO *bp, const char *str)
 423 {
 424     int n, ret;
 425
 426     n = strlen(str);
 427     ret = BIO_write(bp, str, n);
 428     return ret;
 429 }
 430
 431 BIO *BIO_new_buffer_ssl_connect(SSL_CTX *ctx)
 432 {
 433 #ifndef OPENSSL_NO_SOCK
 434     BIO *ret = NULL, *buf = NULL, *ssl = NULL;
 435
 436     if ((buf = BIO_new(BIO_f_buffer())) == NULL)
 437         return NULL;
 438     if ((ssl = BIO_new_ssl_connect(ctx)) == NULL)
 439         goto err;
 440     if ((ret = BIO_push(buf, ssl)) == NULL)
 441         goto err;
 442     return ret;
 443  err:
 444     BIO_free(buf);
 445     BIO_free(ssl);
 446 #endif
 447     return NULL;
 448 }
 449
 450 BIO *BIO_new_ssl_connect(SSL_CTX *ctx)
 451 {
 452 #ifndef OPENSSL_NO_SOCK
 453     BIO *ret = NULL, *con = NULL, *ssl = NULL;
 454
 455     if ((con = BIO_new(BIO_s_connect())) == NULL)
 456         return NULL;
 457     if ((ssl = BIO_new_ssl(ctx, 1)) == NULL)
 458         goto err;
 459     if ((ret = BIO_push(ssl, con)) == NULL)
 460         goto err;
 461     return ret;
 462  err:
 463     BIO_free(ssl);
 464     BIO_free(con);
 465 #endif
 466     return NULL;
 467 }
 468
 469 BIO *BIO_new_ssl(SSL_CTX *ctx, int client)
 470 {
 471     BIO *ret;
 472     SSL *ssl;
 473
 474     if ((ret = BIO_new(BIO_f_ssl())) == NULL)
 475         return NULL;
 476     if ((ssl = SSL_new(ctx)) == NULL) {
 477         BIO_free(ret);
 478         return NULL;
 479     }
 480     if (client)
 481         SSL_set_connect_state(ssl);
 482     else
 483         SSL_set_accept_state(ssl);
 484
 485     BIO_set_ssl(ret, ssl, BIO_CLOSE);
 486     return ret;
 487 }
 488
 489 int BIO_ssl_copy_session_id(BIO *t, BIO *f)
 490 {
 491     BIO_SSL *tdata, *fdata;
 492     t = BIO_find_type(t, BIO_TYPE_SSL);
 493     f = BIO_find_type(f, BIO_TYPE_SSL);
 494     if ((t == NULL) || (f == NULL))
 495         return 0;
 496     tdata = BIO_get_data(t);
 497     fdata = BIO_get_data(f);
 498     if ((tdata->ssl == NULL) || (fdata->ssl == NULL))
 499         return 0;
 500     if (!SSL_copy_session_id(tdata->ssl, (fdata->ssl)))
 501         return 0;
 502     return 1;
 503 }
 504
 505 void BIO_ssl_shutdown(BIO *b)
 506 {
 507     BIO_SSL *bdata;
 508
 509     for (; b != NULL; b = BIO_next(b)) {
 510         if (BIO_method_type(b) != BIO_TYPE_SSL)
 511             continue;
 512         bdata = BIO_get_data(b);
 513         if (bdata != NULL && bdata->ssl != NULL)
 514             SSL_shutdown(bdata->ssl);
 515     }
 516 }