2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
58 /* ====================================================================
59 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
87 * 6. Redistributions of any form whatsoever must retain the following
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
116 #include "ssl_locl.h"
117 #include <openssl/evp.h>
118 #include <openssl/buffer.h>
120 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
121 unsigned int len, int create_empty_fragment);
122 static int ssl3_get_record(SSL *s);
124 int ssl3_read_n(SSL *s, int n, int max, int extend)
127 * If extend == 0, obtain new n-byte packet; if extend == 1, increase
128 * packet by another n bytes. The packet will be in the sub-array of
129 * s->s3->rbuf.buf specified by s->packet and s->packet_length. (If
130 * s->read_ahead is set, 'max' bytes may be stored in rbuf [plus
131 * s->packet_length bytes if extend == 1].)
136 /* start with empty packet ... */
137 if (s->s3->rbuf.left == 0)
138 s->s3->rbuf.offset = 0;
139 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
140 s->packet_length = 0;
141 /* ... now we can act as if 'extend' was set */
145 * For DTLS/UDP reads should not span multiple packets because the read
146 * operation returns the whole packet at once (as long as it fits into
149 if (SSL_version(s) == DTLS1_VERSION) {
150 if (s->s3->rbuf.left == 0 && extend)
152 if (s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
153 n = s->s3->rbuf.left;
156 /* if there is enough in the buffer from a previous read, take some */
157 if (s->s3->rbuf.left >= (int)n) {
158 s->packet_length += n;
159 s->s3->rbuf.left -= n;
160 s->s3->rbuf.offset += n;
164 /* else we need to read more data */
169 /* avoid buffer overflow */
170 int max_max = s->s3->rbuf.len - s->packet_length;
174 if (n > max) { /* does not happen */
175 SSLerr(SSL_F_SSL3_READ_N, ERR_R_INTERNAL_ERROR);
179 off = s->packet_length;
180 newb = s->s3->rbuf.left;
182 * Move any available bytes to front of buffer: 'off' bytes already
183 * pointed to by 'packet', 'newb' extra ones at the end
185 if (s->packet != s->s3->rbuf.buf) {
187 memmove(s->s3->rbuf.buf, s->packet, off + newb);
188 s->packet = s->s3->rbuf.buf;
193 * Now we have off+newb bytes at the front of s->s3->rbuf.buf and
194 * need to read in more until we have off+n (up to off+max if
199 if (s->rbio != NULL) {
200 s->rwstate = SSL_READING;
201 i = BIO_read(s->rbio, &(s->s3->rbuf.buf[off + newb]), max - newb);
203 SSLerr(SSL_F_SSL3_READ_N, SSL_R_READ_BIO_NOT_SET);
208 s->s3->rbuf.left = newb;
213 * reads should *never* span multiple packets for DTLS because the
214 * underlying transport protocol is message oriented as opposed to
215 * byte oriented as in the TLS case.
217 if (SSL_version(s) == DTLS1_VERSION) {
219 n = newb; /* makes the while condition false */
223 /* done reading, now the book-keeping */
224 s->s3->rbuf.offset = off + n;
225 s->s3->rbuf.left = newb - n;
226 s->packet_length += n;
227 s->rwstate = SSL_NOTHING;
232 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that
233 * will be processed per call to ssl3_get_record. Without this limit an
234 * attacker could send empty records at a faster rate than we can process and
235 * cause ssl3_get_record to loop forever.
237 #define MAX_EMPTY_RECORDS 32
240 * Call this to get a new input record.
241 * It will return <= 0 if more data is needed, normally due to an error
242 * or non-blocking IO.
243 * When it finishes, one packet has been decoded and can be found in
244 * ssl->s3->rrec.type - is the type of record
245 * ssl->s3->rrec.data, - data
246 * ssl->s3->rrec.length, - number of bytes
248 /* used only by ssl3_read_bytes */
249 static int ssl3_get_record(SSL *s)
251 int ssl_major, ssl_minor, al;
252 int enc_err, n, i, ret = -1;
256 unsigned char md[EVP_MAX_MD_SIZE];
258 unsigned mac_size, orig_len;
260 unsigned empty_record_count = 0;
265 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
266 extra = SSL3_RT_MAX_EXTRA;
269 if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE) {
271 * actually likely an application error:
272 * SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after ssl3_setup_buffers()
275 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
280 /* check if we have the header */
281 if ((s->rstate != SSL_ST_READ_BODY) ||
282 (s->packet_length < SSL3_RT_HEADER_LENGTH)) {
283 n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
285 return (n); /* error or non-blocking */
286 s->rstate = SSL_ST_READ_BODY;
290 /* Pull apart the header into the SSL3_RECORD */
294 version = (ssl_major << 8) | ssl_minor;
297 /* Lets check version */
298 if (!s->first_packet) {
299 if (version != s->version) {
300 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
301 if ((s->version & 0xFF00) == (version & 0xFF00))
303 * Send back error using their minor version number :-)
305 s->version = (unsigned short)version;
306 al = SSL_AD_PROTOCOL_VERSION;
311 if ((version >> 8) != SSL3_VERSION_MAJOR) {
312 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
316 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
317 al = SSL_AD_RECORD_OVERFLOW;
318 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG);
322 /* now s->rstate == SSL_ST_READ_BODY */
325 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
327 if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) {
328 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
330 n = ssl3_read_n(s, i, i, 1);
332 return (n); /* error or non-blocking io */
334 * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH
339 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
342 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
343 * and we have that many bytes in s->packet
345 rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]);
348 * ok, we can now read from 's->packet' data into 'rr' rr->input points
349 * at rr->length bytes, which need to be copied into rr->data by either
350 * the decryption or by the decompression When the data is 'copied' into
351 * the rr->data buffer, rr->input will be pointed at the new buffer
355 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
356 * bytes of encrypted compressed stuff.
359 /* check is not needed I believe */
360 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
361 al = SSL_AD_RECORD_OVERFLOW;
362 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
366 /* decrypt in place in 'rr->input' */
367 rr->data = rr->input;
369 enc_err = s->method->ssl3_enc->enc(s, 0);
372 * 0: (in non-constant time) if the record is publically invalid.
373 * 1: if the padding is valid
374 * -1: if the padding is invalid
377 al = SSL_AD_DECRYPTION_FAILED;
378 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
382 printf("dec %d\n", rr->length);
385 for (z = 0; z < rr->length; z++)
386 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
391 /* r->length is now the compressed data plus mac */
392 if ((sess != NULL) && (s->enc_read_ctx != NULL) && (s->read_hash != NULL)) {
393 /* s->read_hash != NULL => mac_size != -1 */
394 unsigned char *mac = NULL;
395 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
396 mac_size = EVP_MD_size(s->read_hash);
397 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
400 * kludge: *_cbc_remove_padding passes padding length in rr->type
402 orig_len = rr->length + ((unsigned int)rr->type >> 8);
405 * orig_len is the length of the record before any padding was
406 * removed. This is public information, as is the MAC in use,
407 * therefore we can safely process the record in a different amount
408 * of time if it's too short to possibly contain a MAC.
410 if (orig_len < mac_size ||
411 /* CBC records must have a padding length byte too. */
412 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
413 orig_len < mac_size + 1)) {
414 al = SSL_AD_DECODE_ERROR;
415 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
419 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
421 * We update the length so that the TLS header bytes can be
422 * constructed correctly but we need to extract the MAC in
423 * constant time from within the record, without leaking the
424 * contents of the padding bytes.
427 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
428 rr->length -= mac_size;
431 * In this case there's no padding, so |orig_len| equals
432 * |rec->length| and we checked that there's enough bytes for
435 rr->length -= mac_size;
436 mac = &rr->data[rr->length];
439 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
440 if (i < 0 || mac == NULL
441 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
443 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size)
449 * A separate 'decryption_failed' alert was introduced with TLS 1.0,
450 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
451 * failure is directly visible from the ciphertext anyway, we should
452 * not reveal which kind of error occured -- this might become
453 * visible to an attacker (e.g. via a logfile)
455 al = SSL_AD_BAD_RECORD_MAC;
456 SSLerr(SSL_F_SSL3_GET_RECORD,
457 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
461 /* r->length is now just compressed */
462 if (s->expand != NULL) {
463 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) {
464 al = SSL_AD_RECORD_OVERFLOW;
465 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG);
468 if (!ssl3_do_uncompress(s)) {
469 al = SSL_AD_DECOMPRESSION_FAILURE;
470 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION);
475 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
476 al = SSL_AD_RECORD_OVERFLOW;
477 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
483 * So at this point the following is true
484 * ssl->s3->rrec.type is the type of record
485 * ssl->s3->rrec.length == number of bytes in record
486 * ssl->s3->rrec.off == offset to first valid byte
487 * ssl->s3->rrec.data == where to take bytes from, increment
491 /* we have pulled in a full packet so zero things */
492 s->packet_length = 0;
494 /* just read a 0 length packet */
495 if (rr->length == 0) {
496 empty_record_count++;
497 if (empty_record_count > MAX_EMPTY_RECORDS) {
498 al = SSL_AD_UNEXPECTED_MESSAGE;
499 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL);
508 ssl3_send_alert(s, SSL3_AL_FATAL, al);
513 int ssl3_do_uncompress(SSL *ssl)
515 #ifndef OPENSSL_NO_COMP
519 rr = &(ssl->s3->rrec);
520 i = COMP_expand_block(ssl->expand, rr->comp,
521 SSL3_RT_MAX_PLAIN_LENGTH, rr->data,
532 int ssl3_do_compress(SSL *ssl)
534 #ifndef OPENSSL_NO_COMP
538 wr = &(ssl->s3->wrec);
539 i = COMP_compress_block(ssl->compress, wr->data,
540 SSL3_RT_MAX_COMPRESSED_LENGTH,
541 wr->input, (int)wr->length);
547 wr->input = wr->data;
553 * Call this to write data in records of type 'type' It will return <= 0 if
554 * not all data has been sent or non-blocking IO.
556 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
558 const unsigned char *buf = buf_;
562 s->rwstate = SSL_NOTHING;
563 OPENSSL_assert(s->s3->wnum <= INT_MAX);
567 if (SSL_in_init(s) && !s->in_handshake) {
568 i = s->handshake_func(s);
572 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
578 * ensure that if we end up with a smaller value of data to write out
579 * than the the original len from a write which didn't complete for
580 * non-blocking I/O and also somehow ended up avoiding the check for
581 * this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be
582 * possible to end up with (len-tot) as a large number that will then
583 * promptly send beyond the end of the users buffer ... so we trap and
584 * report the error in a way the user will notice
587 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH);
593 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
594 nw = SSL3_RT_MAX_PLAIN_LENGTH;
598 i = do_ssl3_write(s, type, &(buf[tot]), nw, 0);
605 (type == SSL3_RT_APPLICATION_DATA &&
606 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) {
608 * next chunk of data should get another prepended empty fragment
609 * in ciphersuites with known-IV weakness:
611 s->s3->empty_fragment_done = 0;
621 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
622 unsigned int len, int create_empty_fragment)
624 unsigned char *p, *plen;
625 int i, mac_size, clear = 0;
632 * first check if there is a SSL3_BUFFER still being written out. This
633 * will happen with non blocking IO
635 if (s->s3->wbuf.left != 0)
636 return (ssl3_write_pending(s, type, buf, len));
638 /* If we have an alert to send, lets send it */
639 if (s->s3->alert_dispatch) {
640 i = s->method->ssl_dispatch_alert(s);
643 /* if it went, fall through and send more stuff */
646 if (len == 0 && !create_empty_fragment)
653 if ((sess == NULL) ||
654 (s->enc_write_ctx == NULL) || (s->write_hash == NULL))
660 mac_size = EVP_MD_size(s->write_hash);
663 * 'create_empty_fragment' is true only when this function calls itself
665 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) {
667 * countermeasure against known-IV weakness in CBC ciphersuites (see
668 * http://www.openssl.org/~bodo/tls-cbc.txt)
671 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
673 * recursive function call with 'create_empty_fragment' set; this
674 * prepares and buffers the data for an empty fragment (these
675 * 'prefix_len' bytes are sent out later together with the actual
678 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
682 if (s->s3->wbuf.len <
683 (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) {
684 /* insufficient space */
685 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
690 s->s3->empty_fragment_done = 1;
693 p = wb->buf + prefix_len;
695 /* write the header */
697 *(p++) = type & 0xff;
700 *(p++) = (s->version >> 8);
701 *(p++) = s->version & 0xff;
703 /* field where we are to write out packet length */
707 /* lets setup the record stuff. */
709 wr->length = (int)len;
710 wr->input = (unsigned char *)buf;
713 * we now 'read' from wr->input, wr->length bytes into wr->data
716 /* first we compress */
717 if (s->compress != NULL) {
718 if (!ssl3_do_compress(s)) {
719 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE);
723 memcpy(wr->data, wr->input, wr->length);
724 wr->input = wr->data;
728 * we should still have the output to wr->data and the input from
729 * wr->input. Length should be wr->length. wr->data still points in the
734 s->method->ssl3_enc->mac(s, &(p[wr->length]), 1);
735 wr->length += mac_size;
740 /* ssl3_enc can only have an error on read */
741 s->method->ssl3_enc->enc(s, 1);
743 /* record length after mac and block padding */
744 s2n(wr->length, plen);
747 * we should now have wr->data pointing to the encrypted data, which is
750 wr->type = type; /* not needed but helps for debugging */
751 wr->length += SSL3_RT_HEADER_LENGTH;
753 if (create_empty_fragment) {
755 * we are in a recursive call; just return the length, don't write
761 /* now let's set up wb */
762 wb->left = prefix_len + wr->length;
766 * memorize arguments so that ssl3_write_pending can detect bad write
769 s->s3->wpend_tot = len;
770 s->s3->wpend_buf = buf;
771 s->s3->wpend_type = type;
772 s->s3->wpend_ret = len;
774 /* we now just need to write the buffer */
775 return ssl3_write_pending(s, type, buf, len);
780 /* if s->s3->wbuf.left != 0, we need to call this */
781 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
787 if ((s->s3->wpend_tot > (int)len)
788 || ((s->s3->wpend_buf != buf) &&
789 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
790 || (s->s3->wpend_type != type)) {
791 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY);
797 if (s->wbio != NULL) {
798 s->rwstate = SSL_WRITING;
799 i = BIO_write(s->wbio,
800 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
801 (unsigned int)s->s3->wbuf.left);
803 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET);
806 if (i == s->s3->wbuf.left) {
807 s->s3->wbuf.left = 0;
808 s->rwstate = SSL_NOTHING;
809 return (s->s3->wpend_ret);
811 if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER) {
813 * For DTLS, just drop it. That's kind of the whole point in
814 * using a datagram service
816 s->s3->wbuf.left = 0;
820 s->s3->wbuf.offset += i;
821 s->s3->wbuf.left -= i;
826 * Return up to 'len' payload bytes received in 'type' records.
827 * 'type' is one of the following:
829 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
830 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
831 * - 0 (during a shutdown, no data has to be returned)
833 * If we don't have stored data to work from, read a SSL/TLS record first
834 * (possibly multiple records if we still don't have anything to return).
836 * This function must handle any surprises the peer may have for us, such as
837 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
838 * a surprise, but handled as if it were), or renegotiation requests.
839 * Also if record payloads contain fragments too small to process, we store
840 * them until there is enough for the respective protocol (the record protocol
841 * may use arbitrary fragmentation and even interleaving):
842 * Change cipher spec protocol
843 * just 1 byte needed, no need for keeping anything stored
845 * 2 bytes needed (AlertLevel, AlertDescription)
847 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
848 * to detect unexpected Client Hello and Hello Request messages
849 * here, anything else is handled by higher layers
850 * Application data protocol
851 * none of our business
853 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
858 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
860 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
861 if (!ssl3_setup_buffers(s))
864 if ((type && (type != SSL3_RT_APPLICATION_DATA)
865 && (type != SSL3_RT_HANDSHAKE)) || (peek
867 SSL3_RT_APPLICATION_DATA))) {
868 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
872 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
873 /* (partially) satisfy request from storage */
875 unsigned char *src = s->s3->handshake_fragment;
876 unsigned char *dst = buf;
881 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) {
884 s->s3->handshake_fragment_len--;
887 /* move any remaining fragment bytes: */
888 for (k = 0; k < s->s3->handshake_fragment_len; k++)
889 s->s3->handshake_fragment[k] = *src++;
894 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
897 if (!s->in_handshake && SSL_in_init(s)) {
898 /* type == SSL3_RT_APPLICATION_DATA */
899 i = s->handshake_func(s);
903 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
908 s->rwstate = SSL_NOTHING;
911 * s->s3->rrec.type - is the type of record
912 * s->s3->rrec.data, - data
913 * s->s3->rrec.off, - offset into 'data' for next read
914 * s->s3->rrec.length, - number of bytes.
918 /* get new packet if necessary */
919 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
920 ret = ssl3_get_record(s);
926 * Reset the count of consecutive warning alerts if we've got a non-empty
927 * record that isn't an alert.
929 if (rr->type != SSL3_RT_ALERT && rr->length != 0)
930 s->s3->alert_count = 0;
932 /* we now have a packet which can be read and processed */
934 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
935 * reset by ssl3_get_finished */
936 && (rr->type != SSL3_RT_HANDSHAKE)) {
937 al = SSL_AD_UNEXPECTED_MESSAGE;
938 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
943 * If the other end has shut down, throw anything we read away (even in
946 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
948 s->rwstate = SSL_NOTHING;
952 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
953 * SSL3_RT_HANDSHAKE */
955 * make sure that we are not getting application data when we are
956 * doing a handshake for the first time
958 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
959 (s->enc_read_ctx == NULL)) {
960 al = SSL_AD_UNEXPECTED_MESSAGE;
961 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
968 if ((unsigned int)len > rr->length)
971 n = (unsigned int)len;
973 memcpy(buf, &(rr->data[rr->off]), n);
977 if (rr->length == 0) {
978 s->rstate = SSL_ST_READ_HEADER;
986 * If we get here, then type != rr->type; if we have a handshake message,
987 * then it was unexpected (Hello Request or Client Hello).
991 * In case of record types for which we have 'fragment' storage, fill
992 * that so that we can process the data at a fixed place.
995 unsigned int dest_maxlen = 0;
996 unsigned char *dest = NULL;
997 unsigned int *dest_len = NULL;
999 if (rr->type == SSL3_RT_HANDSHAKE) {
1000 dest_maxlen = sizeof s->s3->handshake_fragment;
1001 dest = s->s3->handshake_fragment;
1002 dest_len = &s->s3->handshake_fragment_len;
1003 } else if (rr->type == SSL3_RT_ALERT) {
1004 dest_maxlen = sizeof s->s3->alert_fragment;
1005 dest = s->s3->alert_fragment;
1006 dest_len = &s->s3->alert_fragment_len;
1009 if (dest_maxlen > 0) {
1010 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1012 n = rr->length; /* available bytes */
1014 /* now move 'n' bytes: */
1016 dest[(*dest_len)++] = rr->data[rr->off++];
1020 if (*dest_len < dest_maxlen)
1021 goto start; /* fragment was too small */
1026 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1027 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1028 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1031 /* If we are a client, check for an incoming 'Hello Request': */
1033 (s->s3->handshake_fragment_len >= 4) &&
1034 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1035 (s->session != NULL) && (s->session->cipher != NULL)) {
1036 s->s3->handshake_fragment_len = 0;
1038 if ((s->s3->handshake_fragment[1] != 0) ||
1039 (s->s3->handshake_fragment[2] != 0) ||
1040 (s->s3->handshake_fragment[3] != 0)) {
1041 al = SSL_AD_DECODE_ERROR;
1042 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
1046 if (s->msg_callback)
1047 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1048 s->s3->handshake_fragment, 4, s,
1049 s->msg_callback_arg);
1051 if (SSL_is_init_finished(s) &&
1052 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1053 !s->s3->renegotiate) {
1054 ssl3_renegotiate(s);
1055 if (ssl3_renegotiate_check(s)) {
1056 i = s->handshake_func(s);
1060 SSLerr(SSL_F_SSL3_READ_BYTES,
1061 SSL_R_SSL_HANDSHAKE_FAILURE);
1065 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1066 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1069 * In the case where we try to read application data,
1070 * but we trigger an SSL handshake, we return -1 with
1071 * the retry option set. Otherwise renegotiation may
1072 * cause nasty problems in the blocking world
1074 s->rwstate = SSL_READING;
1075 bio = SSL_get_rbio(s);
1076 BIO_clear_retry_flags(bio);
1077 BIO_set_retry_read(bio);
1084 * we either finished a handshake or ignored the request, now try
1085 * again to obtain the (application) data we were asked for
1090 * If we are a server and get a client hello when renegotiation isn't
1091 * allowed send back a no renegotiation alert and carry on. WARNING:
1092 * experimental code, needs reviewing (steve)
1095 SSL_is_init_finished(s) &&
1096 !s->s3->send_connection_binding &&
1097 (s->version > SSL3_VERSION) &&
1098 (s->s3->handshake_fragment_len >= 4) &&
1099 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1100 (s->session != NULL) && (s->session->cipher != NULL) &&
1101 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
1103 * s->s3->handshake_fragment_len = 0;
1106 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1109 if (s->s3->alert_fragment_len >= 2) {
1110 int alert_level = s->s3->alert_fragment[0];
1111 int alert_descr = s->s3->alert_fragment[1];
1113 s->s3->alert_fragment_len = 0;
1115 if (s->msg_callback)
1116 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1117 s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1119 if (s->info_callback != NULL)
1120 cb = s->info_callback;
1121 else if (s->ctx->info_callback != NULL)
1122 cb = s->ctx->info_callback;
1125 j = (alert_level << 8) | alert_descr;
1126 cb(s, SSL_CB_READ_ALERT, j);
1129 if (alert_level == 1) { /* warning */
1130 s->s3->warn_alert = alert_descr;
1132 s->s3->alert_count++;
1133 if (s->s3->alert_count == MAX_WARN_ALERT_COUNT) {
1134 al = SSL_AD_UNEXPECTED_MESSAGE;
1135 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS);
1139 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1140 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1144 * This is a warning but we receive it if we requested
1145 * renegotiation and the peer denied it. Terminate with a fatal
1146 * alert because if application tried to renegotiatie it
1147 * presumably had a good reason and expects it to succeed. In
1148 * future we might have a renegotiation where we don't care if
1149 * the peer refused it where we carry on.
1151 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) {
1152 al = SSL_AD_HANDSHAKE_FAILURE;
1153 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION);
1156 } else if (alert_level == 2) { /* fatal */
1159 s->rwstate = SSL_NOTHING;
1160 s->s3->fatal_alert = alert_descr;
1161 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1162 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1163 ERR_add_error_data(2, "SSL alert number ", tmp);
1164 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1165 SSL_CTX_remove_session(s->ctx, s->session);
1168 al = SSL_AD_ILLEGAL_PARAMETER;
1169 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
1176 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
1178 s->rwstate = SSL_NOTHING;
1183 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1185 * 'Change Cipher Spec' is just a single byte, so we know exactly
1186 * what the record payload has to look like
1188 if ((rr->length != 1) || (rr->off != 0) ||
1189 (rr->data[0] != SSL3_MT_CCS)) {
1190 al = SSL_AD_ILLEGAL_PARAMETER;
1191 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1195 /* Check we have a cipher to change to */
1196 if (s->s3->tmp.new_cipher == NULL) {
1197 al = SSL_AD_UNEXPECTED_MESSAGE;
1198 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1202 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) {
1203 al = SSL_AD_UNEXPECTED_MESSAGE;
1204 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1208 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1212 if (s->msg_callback)
1213 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1214 rr->data, 1, s, s->msg_callback_arg);
1216 s->s3->change_cipher_spec = 1;
1217 if (!ssl3_do_change_cipher_spec(s))
1224 * Unexpected handshake message (Client Hello, or protocol violation)
1226 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) {
1227 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1228 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1229 #if 0 /* worked only because C operator preferences
1230 * are not as expected (and because this is
1231 * not really needed for clients except for
1232 * detecting protocol violations): */
1233 s->state = SSL_ST_BEFORE | (s->server)
1234 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1236 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1240 i = s->handshake_func(s);
1244 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1248 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1249 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1252 * In the case where we try to read application data, but we
1253 * trigger an SSL handshake, we return -1 with the retry
1254 * option set. Otherwise renegotiation may cause nasty
1255 * problems in the blocking world
1257 s->rwstate = SSL_READING;
1258 bio = SSL_get_rbio(s);
1259 BIO_clear_retry_flags(bio);
1260 BIO_set_retry_read(bio);
1269 #ifndef OPENSSL_NO_TLS
1270 /* TLS just ignores unknown message types */
1271 if (s->version == TLS1_VERSION) {
1276 al = SSL_AD_UNEXPECTED_MESSAGE;
1277 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1279 case SSL3_RT_CHANGE_CIPHER_SPEC:
1281 case SSL3_RT_HANDSHAKE:
1283 * we already handled all of these, with the possible exception of
1284 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1285 * happen when type != rr->type
1287 al = SSL_AD_UNEXPECTED_MESSAGE;
1288 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1290 case SSL3_RT_APPLICATION_DATA:
1292 * At this point, we were expecting handshake data, but have
1293 * application data. If the library was running inside ssl3_read()
1294 * (i.e. in_read_app_data is set) and it makes sense to read
1295 * application data at this point (session renegotiation not yet
1296 * started), we will indulge it.
1298 if (s->s3->in_read_app_data &&
1299 (s->s3->total_renegotiations != 0) &&
1300 (((s->state & SSL_ST_CONNECT) &&
1301 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1302 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1303 ) || ((s->state & SSL_ST_ACCEPT) &&
1304 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1305 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1308 s->s3->in_read_app_data = 2;
1311 al = SSL_AD_UNEXPECTED_MESSAGE;
1312 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1319 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1324 int ssl3_do_change_cipher_spec(SSL *s)
1330 if (s->state & SSL_ST_ACCEPT)
1331 i = SSL3_CHANGE_CIPHER_SERVER_READ;
1333 i = SSL3_CHANGE_CIPHER_CLIENT_READ;
1335 if (s->s3->tmp.key_block == NULL) {
1336 if (s->session == NULL || s->session->master_key_length == 0) {
1337 /* might happen if dtls1_read_bytes() calls this */
1338 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,
1339 SSL_R_CCS_RECEIVED_EARLY);
1343 s->session->cipher = s->s3->tmp.new_cipher;
1344 if (!s->method->ssl3_enc->setup_key_block(s))
1348 if (!s->method->ssl3_enc->change_cipher_state(s, i))
1352 * we have to record the message digest at this point so we can get it
1353 * before we read the finished message
1355 if (s->state & SSL_ST_CONNECT) {
1356 sender = s->method->ssl3_enc->server_finished_label;
1357 slen = s->method->ssl3_enc->server_finished_label_len;
1359 sender = s->method->ssl3_enc->client_finished_label;
1360 slen = s->method->ssl3_enc->client_finished_label_len;
1363 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1365 (s->s3->finish_dgst1),
1367 (s->s3->finish_dgst2),
1370 s->s3->tmp.peer_finish_md);
1375 int ssl3_send_alert(SSL *s, int level, int desc)
1377 /* Map tls/ssl alert value to correct one */
1378 desc = s->method->ssl3_enc->alert_value(desc);
1379 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1380 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
1381 * protocol_version alerts */
1384 /* If a fatal one, remove from cache */
1385 if ((level == 2) && (s->session != NULL))
1386 SSL_CTX_remove_session(s->ctx, s->session);
1388 s->s3->alert_dispatch = 1;
1389 s->s3->send_alert[0] = level;
1390 s->s3->send_alert[1] = desc;
1391 if (s->s3->wbuf.left == 0) /* data still being written out? */
1392 return s->method->ssl_dispatch_alert(s);
1394 * else data is still being written out, we will get written some time in
1400 int ssl3_dispatch_alert(SSL *s)
1403 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1405 s->s3->alert_dispatch = 0;
1406 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1408 s->s3->alert_dispatch = 1;
1411 * Alert sent to BIO. If it is important, flush it now. If the
1412 * message does not get sent due to non-blocking IO, we will not
1415 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1416 (void)BIO_flush(s->wbio);
1418 if (s->msg_callback)
1419 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1420 2, s, s->msg_callback_arg);
1422 if (s->info_callback != NULL)
1423 cb = s->info_callback;
1424 else if (s->ctx->info_callback != NULL)
1425 cb = s->ctx->info_callback;
1428 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1429 cb(s, SSL_CB_WRITE_ALERT, j);