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].)
143 if (!ssl3_setup_read_buffer(s))
147 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
148 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
149 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
153 /* start with empty packet ... */
156 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) {
158 * check if next packet length is large enough to justify payload
161 pkt = rb->buf + rb->offset;
162 if (pkt[0] == SSL3_RT_APPLICATION_DATA
163 && (pkt[3] << 8 | pkt[4]) >= 128) {
165 * Note that even if packet is corrupted and its length field
166 * is insane, we can only be led to wrong decision about
167 * whether memmove will occur or not. Header values has no
168 * effect on memmove arguments and therefore no buffer
169 * overrun can be triggered.
171 memmove(rb->buf + align, pkt, left);
175 s->packet = rb->buf + rb->offset;
176 s->packet_length = 0;
177 /* ... now we can act as if 'extend' was set */
181 * For DTLS/UDP reads should not span multiple packets because the read
182 * operation returns the whole packet at once (as long as it fits into
185 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) {
186 if (left == 0 && extend)
188 if (left > 0 && n > left)
192 /* if there is enough in the buffer from a previous read, take some */
194 s->packet_length += n;
200 /* else we need to read more data */
202 len = s->packet_length;
203 pkt = rb->buf + align;
205 * Move any available bytes to front of buffer: 'len' bytes already
206 * pointed to by 'packet', 'left' extra ones at the end
208 if (s->packet != pkt) { /* len > 0 */
209 memmove(pkt, s->packet, len + left);
211 rb->offset = len + align;
214 if (n > (int)(rb->len - rb->offset)) { /* does not happen */
215 SSLerr(SSL_F_SSL3_READ_N, ERR_R_INTERNAL_ERROR);
220 /* ignore max parameter */
225 if (max > (int)(rb->len - rb->offset))
226 max = rb->len - rb->offset;
231 * Now we have len+left bytes at the front of s->s3->rbuf.buf and
232 * need to read in more until we have len+n (up to len+max if
237 if (s->rbio != NULL) {
238 s->rwstate = SSL_READING;
239 i = BIO_read(s->rbio, pkt + len + left, max - left);
241 SSLerr(SSL_F_SSL3_READ_N, SSL_R_READ_BIO_NOT_SET);
247 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
248 SSL_version(s) != DTLS1_VERSION
249 && SSL_version(s) != DTLS1_BAD_VER)
251 ssl3_release_read_buffer(s);
256 * reads should *never* span multiple packets for DTLS because the
257 * underlying transport protocol is message oriented as opposed to
258 * byte oriented as in the TLS case.
260 if (SSL_version(s) == DTLS1_VERSION
261 || SSL_version(s) == DTLS1_BAD_VER) {
263 n = left; /* makes the while condition false */
267 /* done reading, now the book-keeping */
270 s->packet_length += n;
271 s->rwstate = SSL_NOTHING;
276 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that
277 * will be processed per call to ssl3_get_record. Without this limit an
278 * attacker could send empty records at a faster rate than we can process and
279 * cause ssl3_get_record to loop forever.
281 #define MAX_EMPTY_RECORDS 32
284 * Call this to get a new input record.
285 * It will return <= 0 if more data is needed, normally due to an error
286 * or non-blocking IO.
287 * When it finishes, one packet has been decoded and can be found in
288 * ssl->s3->rrec.type - is the type of record
289 * ssl->s3->rrec.data, - data
290 * ssl->s3->rrec.length, - number of bytes
292 /* used only by ssl3_read_bytes */
293 static int ssl3_get_record(SSL *s)
295 int ssl_major, ssl_minor, al;
296 int enc_err, n, i, ret = -1;
300 unsigned char md[EVP_MAX_MD_SIZE];
302 unsigned mac_size, orig_len;
304 unsigned empty_record_count = 0;
309 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
310 extra = SSL3_RT_MAX_EXTRA;
313 if (extra && !s->s3->init_extra) {
315 * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after
316 * ssl3_setup_buffers() was done
318 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
323 /* check if we have the header */
324 if ((s->rstate != SSL_ST_READ_BODY) ||
325 (s->packet_length < SSL3_RT_HEADER_LENGTH)) {
326 n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
328 return (n); /* error or non-blocking */
329 s->rstate = SSL_ST_READ_BODY;
333 /* Pull apart the header into the SSL3_RECORD */
337 version = (ssl_major << 8) | ssl_minor;
340 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
343 /* Lets check version */
344 if (!s->first_packet) {
345 if (version != s->version) {
346 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
347 if ((s->version & 0xFF00) == (version & 0xFF00))
349 * Send back error using their minor version number :-)
351 s->version = (unsigned short)version;
352 al = SSL_AD_PROTOCOL_VERSION;
357 if ((version >> 8) != SSL3_VERSION_MAJOR) {
358 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
362 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) {
363 al = SSL_AD_RECORD_OVERFLOW;
364 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG);
368 /* now s->rstate == SSL_ST_READ_BODY */
371 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
373 if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) {
374 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
376 n = ssl3_read_n(s, i, i, 1);
378 return (n); /* error or non-blocking io */
380 * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH
385 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
388 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
389 * and we have that many bytes in s->packet
391 rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]);
394 * ok, we can now read from 's->packet' data into 'rr' rr->input points
395 * at rr->length bytes, which need to be copied into rr->data by either
396 * the decryption or by the decompression When the data is 'copied' into
397 * the rr->data buffer, rr->input will be pointed at the new buffer
401 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
402 * bytes of encrypted compressed stuff.
405 /* check is not needed I believe */
406 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
407 al = SSL_AD_RECORD_OVERFLOW;
408 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
412 /* decrypt in place in 'rr->input' */
413 rr->data = rr->input;
415 enc_err = s->method->ssl3_enc->enc(s, 0);
418 * 0: (in non-constant time) if the record is publically invalid.
419 * 1: if the padding is valid
420 * -1: if the padding is invalid
423 al = SSL_AD_DECRYPTION_FAILED;
424 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
428 printf("dec %d\n", rr->length);
431 for (z = 0; z < rr->length; z++)
432 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
437 /* r->length is now the compressed data plus mac */
438 if ((sess != NULL) &&
439 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {
440 /* s->read_hash != NULL => mac_size != -1 */
441 unsigned char *mac = NULL;
442 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
443 mac_size = EVP_MD_CTX_size(s->read_hash);
444 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
447 * kludge: *_cbc_remove_padding passes padding length in rr->type
449 orig_len = rr->length + ((unsigned int)rr->type >> 8);
452 * orig_len is the length of the record before any padding was
453 * removed. This is public information, as is the MAC in use,
454 * therefore we can safely process the record in a different amount
455 * of time if it's too short to possibly contain a MAC.
457 if (orig_len < mac_size ||
458 /* CBC records must have a padding length byte too. */
459 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
460 orig_len < mac_size + 1)) {
461 al = SSL_AD_DECODE_ERROR;
462 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
466 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
468 * We update the length so that the TLS header bytes can be
469 * constructed correctly but we need to extract the MAC in
470 * constant time from within the record, without leaking the
471 * contents of the padding bytes.
474 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
475 rr->length -= mac_size;
478 * In this case there's no padding, so |orig_len| equals
479 * |rec->length| and we checked that there's enough bytes for
482 rr->length -= mac_size;
483 mac = &rr->data[rr->length];
486 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
487 if (i < 0 || mac == NULL
488 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
490 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size)
496 * A separate 'decryption_failed' alert was introduced with TLS 1.0,
497 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
498 * failure is directly visible from the ciphertext anyway, we should
499 * not reveal which kind of error occured -- this might become
500 * visible to an attacker (e.g. via a logfile)
502 al = SSL_AD_BAD_RECORD_MAC;
503 SSLerr(SSL_F_SSL3_GET_RECORD,
504 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
508 /* r->length is now just compressed */
509 if (s->expand != NULL) {
510 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) {
511 al = SSL_AD_RECORD_OVERFLOW;
512 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG);
515 if (!ssl3_do_uncompress(s)) {
516 al = SSL_AD_DECOMPRESSION_FAILURE;
517 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION);
522 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
523 al = SSL_AD_RECORD_OVERFLOW;
524 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
530 * So at this point the following is true
531 * ssl->s3->rrec.type is the type of record
532 * ssl->s3->rrec.length == number of bytes in record
533 * ssl->s3->rrec.off == offset to first valid byte
534 * ssl->s3->rrec.data == where to take bytes from, increment
538 /* we have pulled in a full packet so zero things */
539 s->packet_length = 0;
541 /* just read a 0 length packet */
542 if (rr->length == 0) {
543 empty_record_count++;
544 if (empty_record_count > MAX_EMPTY_RECORDS) {
545 al = SSL_AD_UNEXPECTED_MESSAGE;
546 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL);
552 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type,
559 ssl3_send_alert(s, SSL3_AL_FATAL, al);
564 int ssl3_do_uncompress(SSL *ssl)
566 #ifndef OPENSSL_NO_COMP
570 rr = &(ssl->s3->rrec);
571 i = COMP_expand_block(ssl->expand, rr->comp,
572 SSL3_RT_MAX_PLAIN_LENGTH, rr->data,
583 int ssl3_do_compress(SSL *ssl)
585 #ifndef OPENSSL_NO_COMP
589 wr = &(ssl->s3->wrec);
590 i = COMP_compress_block(ssl->compress, wr->data,
591 SSL3_RT_MAX_COMPRESSED_LENGTH,
592 wr->input, (int)wr->length);
598 wr->input = wr->data;
604 * Call this to write data in records of type 'type' It will return <= 0 if
605 * not all data has been sent or non-blocking IO.
607 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
609 const unsigned char *buf = buf_;
613 s->rwstate = SSL_NOTHING;
614 OPENSSL_assert(s->s3->wnum <= INT_MAX);
618 if (SSL_in_init(s) && !s->in_handshake) {
619 i = s->handshake_func(s);
623 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
629 * ensure that if we end up with a smaller value of data to write out
630 * than the the original len from a write which didn't complete for
631 * non-blocking I/O and also somehow ended up avoiding the check for
632 * this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be
633 * possible to end up with (len-tot) as a large number that will then
634 * promptly send beyond the end of the users buffer ... so we trap and
635 * report the error in a way the user will notice
638 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH);
644 if (n > s->max_send_fragment)
645 nw = s->max_send_fragment;
649 i = do_ssl3_write(s, type, &(buf[tot]), nw, 0);
656 (type == SSL3_RT_APPLICATION_DATA &&
657 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) {
659 * next chunk of data should get another prepended empty fragment
660 * in ciphersuites with known-IV weakness:
662 s->s3->empty_fragment_done = 0;
672 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
673 unsigned int len, int create_empty_fragment)
675 unsigned char *p, *plen;
676 int i, mac_size, clear = 0;
680 SSL3_BUFFER *wb = &(s->s3->wbuf);
684 * first check if there is a SSL3_BUFFER still being written out. This
685 * will happen with non blocking IO
688 return (ssl3_write_pending(s, type, buf, len));
690 /* If we have an alert to send, lets send it */
691 if (s->s3->alert_dispatch) {
692 i = s->method->ssl_dispatch_alert(s);
695 /* if it went, fall through and send more stuff */
699 if (!ssl3_setup_write_buffer(s))
702 if (len == 0 && !create_empty_fragment)
708 if ((sess == NULL) ||
709 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
715 mac_size = EVP_MD_CTX_size(s->write_hash);
721 * 'create_empty_fragment' is true only when this function calls itself
723 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) {
725 * countermeasure against known-IV weakness in CBC ciphersuites (see
726 * http://www.openssl.org/~bodo/tls-cbc.txt)
729 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
731 * recursive function call with 'create_empty_fragment' set; this
732 * prepares and buffers the data for an empty fragment (these
733 * 'prefix_len' bytes are sent out later together with the actual
736 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
741 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
743 /* insufficient space */
744 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
749 s->s3->empty_fragment_done = 1;
752 if (create_empty_fragment) {
753 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
755 * extra fragment would be couple of cipher blocks, which would be
756 * multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real
757 * payload, then we can just pretent we simply have two headers.
759 align = (long)wb->buf + 2 * SSL3_RT_HEADER_LENGTH;
760 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
764 } else if (prefix_len) {
765 p = wb->buf + wb->offset + prefix_len;
767 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
768 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
769 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
775 /* write the header */
777 *(p++) = type & 0xff;
780 *(p++) = (s->version >> 8);
781 *(p++) = s->version & 0xff;
783 /* field where we are to write out packet length */
787 /* lets setup the record stuff. */
789 wr->length = (int)len;
790 wr->input = (unsigned char *)buf;
793 * we now 'read' from wr->input, wr->length bytes into wr->data
796 /* first we compress */
797 if (s->compress != NULL) {
798 if (!ssl3_do_compress(s)) {
799 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE);
803 memcpy(wr->data, wr->input, wr->length);
804 wr->input = wr->data;
808 * we should still have the output to wr->data and the input from
809 * wr->input. Length should be wr->length. wr->data still points in the
814 if (s->method->ssl3_enc->mac(s, &(p[wr->length]), 1) < 0)
816 wr->length += mac_size;
821 if (s->method->ssl3_enc->enc(s, 1) < 1)
824 /* record length after mac and block padding */
825 s2n(wr->length, plen);
828 * we should now have wr->data pointing to the encrypted data, which is
831 wr->type = type; /* not needed but helps for debugging */
832 wr->length += SSL3_RT_HEADER_LENGTH;
834 if (create_empty_fragment) {
836 * we are in a recursive call; just return the length, don't write
842 /* now let's set up wb */
843 wb->left = prefix_len + wr->length;
846 * memorize arguments so that ssl3_write_pending can detect bad write
849 s->s3->wpend_tot = len;
850 s->s3->wpend_buf = buf;
851 s->s3->wpend_type = type;
852 s->s3->wpend_ret = len;
854 /* we now just need to write the buffer */
855 return ssl3_write_pending(s, type, buf, len);
860 /* if s->s3->wbuf.left != 0, we need to call this */
861 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
865 SSL3_BUFFER *wb = &(s->s3->wbuf);
868 if ((s->s3->wpend_tot > (int)len)
869 || ((s->s3->wpend_buf != buf) &&
870 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
871 || (s->s3->wpend_type != type)) {
872 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY);
878 if (s->wbio != NULL) {
879 s->rwstate = SSL_WRITING;
880 i = BIO_write(s->wbio,
881 (char *)&(wb->buf[wb->offset]),
882 (unsigned int)wb->left);
884 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET);
890 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
891 SSL_version(s) != DTLS1_VERSION
892 && SSL_version(s) != DTLS1_BAD_VER)
893 ssl3_release_write_buffer(s);
894 s->rwstate = SSL_NOTHING;
895 return (s->s3->wpend_ret);
897 if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER) {
899 * For DTLS, just drop it. That's kind of the whole point in
900 * using a datagram service
912 * Return up to 'len' payload bytes received in 'type' records.
913 * 'type' is one of the following:
915 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
916 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
917 * - 0 (during a shutdown, no data has to be returned)
919 * If we don't have stored data to work from, read a SSL/TLS record first
920 * (possibly multiple records if we still don't have anything to return).
922 * This function must handle any surprises the peer may have for us, such as
923 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
924 * a surprise, but handled as if it were), or renegotiation requests.
925 * Also if record payloads contain fragments too small to process, we store
926 * them until there is enough for the respective protocol (the record protocol
927 * may use arbitrary fragmentation and even interleaving):
928 * Change cipher spec protocol
929 * just 1 byte needed, no need for keeping anything stored
931 * 2 bytes needed (AlertLevel, AlertDescription)
933 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
934 * to detect unexpected Client Hello and Hello Request messages
935 * here, anything else is handled by higher layers
936 * Application data protocol
937 * none of our business
939 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
944 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
946 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
947 if (!ssl3_setup_read_buffer(s))
950 if ((type && (type != SSL3_RT_APPLICATION_DATA)
951 && (type != SSL3_RT_HANDSHAKE)) || (peek
953 SSL3_RT_APPLICATION_DATA))) {
954 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
958 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
959 /* (partially) satisfy request from storage */
961 unsigned char *src = s->s3->handshake_fragment;
962 unsigned char *dst = buf;
967 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) {
970 s->s3->handshake_fragment_len--;
973 /* move any remaining fragment bytes: */
974 for (k = 0; k < s->s3->handshake_fragment_len; k++)
975 s->s3->handshake_fragment[k] = *src++;
980 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
983 if (!s->in_handshake && SSL_in_init(s)) {
984 /* type == SSL3_RT_APPLICATION_DATA */
985 i = s->handshake_func(s);
989 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
994 s->rwstate = SSL_NOTHING;
997 * s->s3->rrec.type - is the type of record
998 * s->s3->rrec.data, - data
999 * s->s3->rrec.off, - offset into 'data' for next read
1000 * s->s3->rrec.length, - number of bytes.
1002 rr = &(s->s3->rrec);
1004 /* get new packet if necessary */
1005 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
1006 ret = ssl3_get_record(s);
1011 /* we now have a packet which can be read and processed */
1013 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1014 * reset by ssl3_get_finished */
1015 && (rr->type != SSL3_RT_HANDSHAKE)) {
1016 al = SSL_AD_UNEXPECTED_MESSAGE;
1017 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1022 * If the other end has shut down, throw anything we read away (even in
1025 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
1027 s->rwstate = SSL_NOTHING;
1031 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
1032 * SSL3_RT_HANDSHAKE */
1034 * make sure that we are not getting application data when we are
1035 * doing a handshake for the first time
1037 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1038 (s->enc_read_ctx == NULL)) {
1039 al = SSL_AD_UNEXPECTED_MESSAGE;
1040 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
1047 if ((unsigned int)len > rr->length)
1050 n = (unsigned int)len;
1052 memcpy(buf, &(rr->data[rr->off]), n);
1056 if (rr->length == 0) {
1057 s->rstate = SSL_ST_READ_HEADER;
1059 if (s->mode & SSL_MODE_RELEASE_BUFFERS
1060 && s->s3->rbuf.left == 0)
1061 ssl3_release_read_buffer(s);
1068 * If we get here, then type != rr->type; if we have a handshake message,
1069 * then it was unexpected (Hello Request or Client Hello).
1073 * In case of record types for which we have 'fragment' storage, fill
1074 * that so that we can process the data at a fixed place.
1077 unsigned int dest_maxlen = 0;
1078 unsigned char *dest = NULL;
1079 unsigned int *dest_len = NULL;
1081 if (rr->type == SSL3_RT_HANDSHAKE) {
1082 dest_maxlen = sizeof s->s3->handshake_fragment;
1083 dest = s->s3->handshake_fragment;
1084 dest_len = &s->s3->handshake_fragment_len;
1085 } else if (rr->type == SSL3_RT_ALERT) {
1086 dest_maxlen = sizeof s->s3->alert_fragment;
1087 dest = s->s3->alert_fragment;
1088 dest_len = &s->s3->alert_fragment_len;
1091 if (dest_maxlen > 0) {
1092 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1094 n = rr->length; /* available bytes */
1096 /* now move 'n' bytes: */
1098 dest[(*dest_len)++] = rr->data[rr->off++];
1102 if (*dest_len < dest_maxlen)
1103 goto start; /* fragment was too small */
1108 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1109 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1110 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1113 /* If we are a client, check for an incoming 'Hello Request': */
1115 (s->s3->handshake_fragment_len >= 4) &&
1116 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1117 (s->session != NULL) && (s->session->cipher != NULL)) {
1118 s->s3->handshake_fragment_len = 0;
1120 if ((s->s3->handshake_fragment[1] != 0) ||
1121 (s->s3->handshake_fragment[2] != 0) ||
1122 (s->s3->handshake_fragment[3] != 0)) {
1123 al = SSL_AD_DECODE_ERROR;
1124 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
1128 if (s->msg_callback)
1129 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1130 s->s3->handshake_fragment, 4, s,
1131 s->msg_callback_arg);
1133 if (SSL_is_init_finished(s) &&
1134 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1135 !s->s3->renegotiate) {
1136 ssl3_renegotiate(s);
1137 if (ssl3_renegotiate_check(s)) {
1138 i = s->handshake_func(s);
1142 SSLerr(SSL_F_SSL3_READ_BYTES,
1143 SSL_R_SSL_HANDSHAKE_FAILURE);
1147 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1148 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1151 * In the case where we try to read application data,
1152 * but we trigger an SSL handshake, we return -1 with
1153 * the retry option set. Otherwise renegotiation may
1154 * cause nasty problems in the blocking world
1156 s->rwstate = SSL_READING;
1157 bio = SSL_get_rbio(s);
1158 BIO_clear_retry_flags(bio);
1159 BIO_set_retry_read(bio);
1166 * we either finished a handshake or ignored the request, now try
1167 * again to obtain the (application) data we were asked for
1172 * If we are a server and get a client hello when renegotiation isn't
1173 * allowed send back a no renegotiation alert and carry on. WARNING:
1174 * experimental code, needs reviewing (steve)
1177 SSL_is_init_finished(s) &&
1178 !s->s3->send_connection_binding &&
1179 (s->version > SSL3_VERSION) &&
1180 (s->s3->handshake_fragment_len >= 4) &&
1181 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1182 (s->session != NULL) && (s->session->cipher != NULL) &&
1183 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
1185 * s->s3->handshake_fragment_len = 0;
1188 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1191 if (s->s3->alert_fragment_len >= 2) {
1192 int alert_level = s->s3->alert_fragment[0];
1193 int alert_descr = s->s3->alert_fragment[1];
1195 s->s3->alert_fragment_len = 0;
1197 if (s->msg_callback)
1198 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1199 s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1201 if (s->info_callback != NULL)
1202 cb = s->info_callback;
1203 else if (s->ctx->info_callback != NULL)
1204 cb = s->ctx->info_callback;
1207 j = (alert_level << 8) | alert_descr;
1208 cb(s, SSL_CB_READ_ALERT, j);
1211 if (alert_level == 1) { /* warning */
1212 s->s3->warn_alert = alert_descr;
1213 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1214 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1218 * This is a warning but we receive it if we requested
1219 * renegotiation and the peer denied it. Terminate with a fatal
1220 * alert because if application tried to renegotiatie it
1221 * presumably had a good reason and expects it to succeed. In
1222 * future we might have a renegotiation where we don't care if
1223 * the peer refused it where we carry on.
1225 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) {
1226 al = SSL_AD_HANDSHAKE_FAILURE;
1227 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION);
1230 } else if (alert_level == 2) { /* fatal */
1233 s->rwstate = SSL_NOTHING;
1234 s->s3->fatal_alert = alert_descr;
1235 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1236 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1237 ERR_add_error_data(2, "SSL alert number ", tmp);
1238 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1239 SSL_CTX_remove_session(s->ctx, s->session);
1242 al = SSL_AD_ILLEGAL_PARAMETER;
1243 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
1250 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
1252 s->rwstate = SSL_NOTHING;
1257 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1259 * 'Change Cipher Spec' is just a single byte, so we know exactly
1260 * what the record payload has to look like
1262 if ((rr->length != 1) || (rr->off != 0) ||
1263 (rr->data[0] != SSL3_MT_CCS)) {
1264 al = SSL_AD_ILLEGAL_PARAMETER;
1265 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1269 /* Check we have a cipher to change to */
1270 if (s->s3->tmp.new_cipher == NULL) {
1271 al = SSL_AD_UNEXPECTED_MESSAGE;
1272 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1276 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) {
1277 al = SSL_AD_UNEXPECTED_MESSAGE;
1278 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1282 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1286 if (s->msg_callback)
1287 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1288 rr->data, 1, s, s->msg_callback_arg);
1290 s->s3->change_cipher_spec = 1;
1291 if (!ssl3_do_change_cipher_spec(s))
1298 * Unexpected handshake message (Client Hello, or protocol violation)
1300 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) {
1301 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1302 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1303 #if 0 /* worked only because C operator preferences
1304 * are not as expected (and because this is
1305 * not really needed for clients except for
1306 * detecting protocol violations): */
1307 s->state = SSL_ST_BEFORE | (s->server)
1308 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1310 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1314 i = s->handshake_func(s);
1318 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1322 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1323 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1326 * In the case where we try to read application data, but we
1327 * trigger an SSL handshake, we return -1 with the retry
1328 * option set. Otherwise renegotiation may cause nasty
1329 * problems in the blocking world
1331 s->rwstate = SSL_READING;
1332 bio = SSL_get_rbio(s);
1333 BIO_clear_retry_flags(bio);
1334 BIO_set_retry_read(bio);
1343 #ifndef OPENSSL_NO_TLS
1344 /* TLS just ignores unknown message types */
1345 if (s->version == TLS1_VERSION) {
1350 al = SSL_AD_UNEXPECTED_MESSAGE;
1351 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1353 case SSL3_RT_CHANGE_CIPHER_SPEC:
1355 case SSL3_RT_HANDSHAKE:
1357 * we already handled all of these, with the possible exception of
1358 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1359 * happen when type != rr->type
1361 al = SSL_AD_UNEXPECTED_MESSAGE;
1362 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1364 case SSL3_RT_APPLICATION_DATA:
1366 * At this point, we were expecting handshake data, but have
1367 * application data. If the library was running inside ssl3_read()
1368 * (i.e. in_read_app_data is set) and it makes sense to read
1369 * application data at this point (session renegotiation not yet
1370 * started), we will indulge it.
1372 if (s->s3->in_read_app_data &&
1373 (s->s3->total_renegotiations != 0) &&
1374 (((s->state & SSL_ST_CONNECT) &&
1375 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1376 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1377 ) || ((s->state & SSL_ST_ACCEPT) &&
1378 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1379 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1382 s->s3->in_read_app_data = 2;
1385 al = SSL_AD_UNEXPECTED_MESSAGE;
1386 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1393 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1398 int ssl3_do_change_cipher_spec(SSL *s)
1404 if (s->state & SSL_ST_ACCEPT)
1405 i = SSL3_CHANGE_CIPHER_SERVER_READ;
1407 i = SSL3_CHANGE_CIPHER_CLIENT_READ;
1409 if (s->s3->tmp.key_block == NULL) {
1410 if (s->session == NULL || s->session->master_key_length == 0) {
1411 /* might happen if dtls1_read_bytes() calls this */
1412 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,
1413 SSL_R_CCS_RECEIVED_EARLY);
1417 s->session->cipher = s->s3->tmp.new_cipher;
1418 if (!s->method->ssl3_enc->setup_key_block(s))
1422 if (!s->method->ssl3_enc->change_cipher_state(s, i))
1426 * we have to record the message digest at this point so we can get it
1427 * before we read the finished message
1429 if (s->state & SSL_ST_CONNECT) {
1430 sender = s->method->ssl3_enc->server_finished_label;
1431 slen = s->method->ssl3_enc->server_finished_label_len;
1433 sender = s->method->ssl3_enc->client_finished_label;
1434 slen = s->method->ssl3_enc->client_finished_label_len;
1437 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1440 s->s3->tmp.peer_finish_md);
1445 int ssl3_send_alert(SSL *s, int level, int desc)
1447 /* Map tls/ssl alert value to correct one */
1448 desc = s->method->ssl3_enc->alert_value(desc);
1449 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1450 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
1451 * protocol_version alerts */
1454 /* If a fatal one, remove from cache */
1455 if ((level == 2) && (s->session != NULL))
1456 SSL_CTX_remove_session(s->ctx, s->session);
1458 s->s3->alert_dispatch = 1;
1459 s->s3->send_alert[0] = level;
1460 s->s3->send_alert[1] = desc;
1461 if (s->s3->wbuf.left == 0) /* data still being written out? */
1462 return s->method->ssl_dispatch_alert(s);
1464 * else data is still being written out, we will get written some time in
1470 int ssl3_dispatch_alert(SSL *s)
1473 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1475 s->s3->alert_dispatch = 0;
1476 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1478 s->s3->alert_dispatch = 1;
1481 * Alert sent to BIO. If it is important, flush it now. If the
1482 * message does not get sent due to non-blocking IO, we will not
1485 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1486 (void)BIO_flush(s->wbio);
1488 if (s->msg_callback)
1489 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1490 2, s, s->msg_callback_arg);
1492 if (s->info_callback != NULL)
1493 cb = s->info_callback;
1494 else if (s->ctx->info_callback != NULL)
1495 cb = s->ctx->info_callback;
1498 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1499 cb(s, SSL_CB_WRITE_ALERT, j);