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).
115 #include "ssl_locl.h"
116 #include <openssl/evp.h>
117 #include <openssl/buffer.h>
119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
120 unsigned int len, int create_empty_fragment);
121 static int ssl3_get_record(SSL *s);
123 int ssl3_read_n(SSL *s, int n, int max, int extend)
125 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
126 * packet by another n bytes.
127 * The packet will be in the sub-array of s->s3->rbuf.buf specified
128 * by s->packet and s->packet_length.
129 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
130 * [plus s->packet_length bytes if extend == 1].)
132 int i,len,left,align=0;
136 if (n <= 0) return n;
140 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
141 align = (int)rb->buf + SSL3_RT_HEADER_LENGTH;
142 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
147 /* start with empty packet ... */
150 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
152 /* check if next packet length is large
153 * enough to justify payload alignment... */
154 pkt = rb->buf + rb->offset;
155 if (pkt[0] == SSL3_RT_APPLICATION_DATA
156 && (pkt[3]<<8|pkt[4]) >= 128)
158 /* Note that even if packet is corrupted
159 * and its length field is insane, we can
160 * only be led to wrong decision about
161 * whether memmove will occur or not.
162 * Header values has no effect on memmove
163 * arguments and therefore no buffer
164 * overrun can be triggered. */
165 memmove (rb->buf+align,pkt,left);
169 s->packet = rb->buf + rb->offset;
170 s->packet_length = 0;
171 /* ... now we can act as if 'extend' was set */
174 /* extend reads should not span multiple packets for DTLS */
175 if ( SSL_version(s) == DTLS1_VERSION &&
178 if ( left > 0 && n > left)
182 /* if there is enough in the buffer from a previous read, take some */
191 /* else we need to read more data */
193 len = s->packet_length;
195 /* Move any available bytes to front of buffer:
196 * 'len' bytes already pointed to by 'packet',
197 * 'left' extra ones at the end */
198 if (s->packet != pkt) /* len > 0 */
200 memmove(pkt, s->packet, len+left);
202 rb->offset = len + align;
205 max = rb->len - rb->offset;
206 if (n > max) /* does not happen */
208 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
217 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
218 * and need to read in more until we have len+n (up to
219 * len+max if possible) */
224 s->rwstate=SSL_READING;
225 i=BIO_read(s->rbio,pkt+len+left, max-left);
229 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
241 /* done reading, now the book-keeping */
244 s->packet_length += n;
245 s->rwstate=SSL_NOTHING;
249 /* Call this to get a new input record.
250 * It will return <= 0 if more data is needed, normally due to an error
251 * or non-blocking IO.
252 * When it finishes, one packet has been decoded and can be found in
253 * ssl->s3->rrec.type - is the type of record
254 * ssl->s3->rrec.data, - data
255 * ssl->s3->rrec.length, - number of bytes
257 /* used only by ssl3_read_bytes */
258 static int ssl3_get_record(SSL *s)
260 int ssl_major,ssl_minor,al;
261 int enc_err,n,i,ret= -1;
265 unsigned char md[EVP_MAX_MD_SIZE];
267 unsigned int mac_size;
270 int decryption_failed_or_bad_record_mac = 0;
271 unsigned char *mac = NULL;
276 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
277 extra=SSL3_RT_MAX_EXTRA;
280 if (extra && !s->s3->init_extra)
282 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
283 * set after ssl3_setup_buffers() was done */
284 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
289 /* check if we have the header */
290 if ( (s->rstate != SSL_ST_READ_BODY) ||
291 (s->packet_length < SSL3_RT_HEADER_LENGTH))
293 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
294 if (n <= 0) return(n); /* error or non-blocking */
295 s->rstate=SSL_ST_READ_BODY;
299 /* Pull apart the header into the SSL3_RECORD */
303 version=(ssl_major<<8)|ssl_minor;
306 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
309 /* Lets check version */
310 if (!s->first_packet)
312 if (version != s->version)
314 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
315 /* Send back error using their
316 * version number :-) */
318 al=SSL_AD_PROTOCOL_VERSION;
323 if ((version>>8) != SSL3_VERSION_MAJOR)
325 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
329 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
331 al=SSL_AD_RECORD_OVERFLOW;
332 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
336 /* now s->rstate == SSL_ST_READ_BODY */
339 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
341 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
343 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
345 n=ssl3_read_n(s,i,i,1);
346 if (n <= 0) return(n); /* error or non-blocking io */
347 /* now n == rr->length,
348 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
351 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
353 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
354 * and we have that many bytes in s->packet
356 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
358 /* ok, we can now read from 's->packet' data into 'rr'
359 * rr->input points at rr->length bytes, which
360 * need to be copied into rr->data by either
361 * the decryption or by the decompression
362 * When the data is 'copied' into the rr->data buffer,
363 * rr->input will be pointed at the new buffer */
365 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
366 * rr->length bytes of encrypted compressed stuff. */
368 /* check is not needed I believe */
369 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
371 al=SSL_AD_RECORD_OVERFLOW;
372 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
376 /* decrypt in place in 'rr->input' */
379 enc_err = s->method->ssl3_enc->enc(s,0);
383 /* SSLerr() and ssl3_send_alert() have been called */
386 /* Otherwise enc_err == -1, which indicates bad padding
387 * (rec->length has not been changed in this case).
388 * To minimize information leaked via timing, we will perform
389 * the MAC computation anyway. */
390 decryption_failed_or_bad_record_mac = 1;
394 printf("dec %d\n",rr->length);
395 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
399 /* r->length is now the compressed data plus mac */
400 if ( (sess == NULL) ||
401 (s->enc_read_ctx == NULL) ||
402 (s->read_hash == NULL))
407 mac_size=EVP_MD_size(s->read_hash);
409 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
411 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
412 al=SSL_AD_RECORD_OVERFLOW;
413 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
416 decryption_failed_or_bad_record_mac = 1;
419 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
420 if (rr->length >= mac_size)
422 rr->length -= mac_size;
423 mac = &rr->data[rr->length];
427 /* record (minus padding) is too short to contain a MAC */
428 #if 0 /* OK only for stream ciphers */
429 al=SSL_AD_DECODE_ERROR;
430 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
433 decryption_failed_or_bad_record_mac = 1;
437 i=s->method->ssl3_enc->mac(s,md,0);
438 if (mac == NULL || memcmp(md, mac, mac_size) != 0)
440 decryption_failed_or_bad_record_mac = 1;
444 if (decryption_failed_or_bad_record_mac)
446 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
447 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
448 * failure is directly visible from the ciphertext anyway,
449 * we should not reveal which kind of error occured -- this
450 * might become visible to an attacker (e.g. via a logfile) */
451 al=SSL_AD_BAD_RECORD_MAC;
452 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
456 /* r->length is now just compressed */
457 if (s->expand != NULL)
459 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
461 al=SSL_AD_RECORD_OVERFLOW;
462 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
465 if (!ssl3_do_uncompress(s))
467 al=SSL_AD_DECOMPRESSION_FAILURE;
468 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
473 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
475 al=SSL_AD_RECORD_OVERFLOW;
476 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
481 /* So at this point the following is true
482 * ssl->s3->rrec.type is the type of record
483 * ssl->s3->rrec.length == number of bytes in record
484 * ssl->s3->rrec.off == offset to first valid byte
485 * ssl->s3->rrec.data == where to take bytes from, increment
489 /* we have pulled in a full packet so zero things */
492 /* just read a 0 length packet */
493 if (rr->length == 0) goto again;
496 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
502 ssl3_send_alert(s,SSL3_AL_FATAL,al);
507 int ssl3_do_uncompress(SSL *ssl)
509 #ifndef OPENSSL_NO_COMP
513 rr= &(ssl->s3->rrec);
514 i=COMP_expand_block(ssl->expand,rr->comp,
515 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
525 int ssl3_do_compress(SSL *ssl)
527 #ifndef OPENSSL_NO_COMP
531 wr= &(ssl->s3->wrec);
532 i=COMP_compress_block(ssl->compress,wr->data,
533 SSL3_RT_MAX_COMPRESSED_LENGTH,
534 wr->input,(int)wr->length);
545 /* Call this to write data in records of type 'type'
546 * It will return <= 0 if not all data has been sent or non-blocking IO.
548 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
550 const unsigned char *buf=buf_;
551 unsigned int tot,n,nw;
554 s->rwstate=SSL_NOTHING;
558 if (SSL_in_init(s) && !s->in_handshake)
560 i=s->handshake_func(s);
561 if (i < 0) return(i);
564 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
572 if (n > s->max_send_fragment)
573 nw=s->max_send_fragment;
577 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
585 (type == SSL3_RT_APPLICATION_DATA &&
586 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
588 /* next chunk of data should get another prepended empty fragment
589 * in ciphersuites with known-IV weakness: */
590 s->s3->empty_fragment_done = 0;
600 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
601 unsigned int len, int create_empty_fragment)
603 unsigned char *p,*plen;
604 int i,mac_size,clear=0;
605 int prefix_len=0,align=0;
607 SSL3_BUFFER *wb=&(s->s3->wbuf);
610 /* first check if there is a SSL3_BUFFER still being written
611 * out. This will happen with non blocking IO */
613 return(ssl3_write_pending(s,type,buf,len));
615 /* If we have an alert to send, lets send it */
616 if (s->s3->alert_dispatch)
618 i=s->method->ssl_dispatch_alert(s);
621 /* if it went, fall through and send more stuff */
624 if (len == 0 && !create_empty_fragment)
630 if ( (sess == NULL) ||
631 (s->enc_write_ctx == NULL) ||
632 (s->write_hash == NULL))
638 mac_size=EVP_MD_size(s->write_hash);
640 /* 'create_empty_fragment' is true only when this function calls itself */
641 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
643 /* countermeasure against known-IV weakness in CBC ciphersuites
644 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
646 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
648 /* recursive function call with 'create_empty_fragment' set;
649 * this prepares and buffers the data for an empty fragment
650 * (these 'prefix_len' bytes are sent out later
651 * together with the actual payload) */
652 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
657 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
659 /* insufficient space */
660 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
665 s->s3->empty_fragment_done = 1;
668 if (create_empty_fragment)
670 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
671 /* extra fragment would be couple of cipher blocks,
672 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
673 * if we want to align the real payload, then we can
674 * just pretent we simply have two headers. */
675 align = (int)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
676 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
683 p = wb->buf + wb->offset + prefix_len;
687 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
688 align = (int)wb->buf + SSL3_RT_HEADER_LENGTH;
689 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
695 /* write the header */
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. */
710 wr->input=(unsigned char *)buf;
712 /* we now 'read' from wr->input, wr->length bytes into
715 /* first we compress */
716 if (s->compress != NULL)
718 if (!ssl3_do_compress(s))
720 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
726 memcpy(wr->data,wr->input,wr->length);
730 /* we should still have the output to wr->data and the input
731 * from wr->input. Length should be wr->length.
732 * wr->data still points in the wb->buf */
736 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
737 wr->length+=mac_size;
742 /* ssl3_enc can only have an error on read */
743 s->method->ssl3_enc->enc(s,1);
745 /* record length after mac and block padding */
746 s2n(wr->length,plen);
748 /* we should now have
749 * wr->data pointing to the encrypted data, which is
751 wr->type=type; /* not needed but helps for debugging */
752 wr->length+=SSL3_RT_HEADER_LENGTH;
754 if (create_empty_fragment)
756 /* we are in a recursive call;
757 * just return the length, don't write out anything here
762 /* now let's set up wb */
763 wb->left = prefix_len + wr->length;
765 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
766 s->s3->wpend_tot=len;
767 s->s3->wpend_buf=buf;
768 s->s3->wpend_type=type;
769 s->s3->wpend_ret=len;
771 /* we now just need to write the buffer */
772 return ssl3_write_pending(s,type,buf,len);
777 /* if s->s3->wbuf.left != 0, we need to call this */
778 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
782 SSL3_BUFFER *wb=&(s->s3->wbuf);
785 if ((s->s3->wpend_tot > (int)len)
786 || ((s->s3->wpend_buf != buf) &&
787 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
788 || (s->s3->wpend_type != type))
790 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
799 s->rwstate=SSL_WRITING;
801 (char *)&(wb->buf[wb->offset]),
802 (unsigned int)wb->left);
806 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
813 s->rwstate=SSL_NOTHING;
814 return(s->s3->wpend_ret);
823 /* Return up to 'len' payload bytes received in 'type' records.
824 * 'type' is one of the following:
826 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
827 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
828 * - 0 (during a shutdown, no data has to be returned)
830 * If we don't have stored data to work from, read a SSL/TLS record first
831 * (possibly multiple records if we still don't have anything to return).
833 * This function must handle any surprises the peer may have for us, such as
834 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
835 * a surprise, but handled as if it were), or renegotiation requests.
836 * Also if record payloads contain fragments too small to process, we store
837 * them until there is enough for the respective protocol (the record protocol
838 * may use arbitrary fragmentation and even interleaving):
839 * Change cipher spec protocol
840 * just 1 byte needed, no need for keeping anything stored
842 * 2 bytes needed (AlertLevel, AlertDescription)
844 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
845 * to detect unexpected Client Hello and Hello Request messages
846 * here, anything else is handled by higher layers
847 * Application data protocol
848 * none of our business
850 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
855 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
857 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
858 if (!ssl3_setup_buffers(s))
861 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
862 (peek && (type != SSL3_RT_APPLICATION_DATA)))
864 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
868 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
869 /* (partially) satisfy request from storage */
871 unsigned char *src = s->s3->handshake_fragment;
872 unsigned char *dst = buf;
877 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
880 len--; s->s3->handshake_fragment_len--;
883 /* move any remaining fragment bytes: */
884 for (k = 0; k < s->s3->handshake_fragment_len; k++)
885 s->s3->handshake_fragment[k] = *src++;
889 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
891 if (!s->in_handshake && SSL_in_init(s))
893 /* type == SSL3_RT_APPLICATION_DATA */
894 i=s->handshake_func(s);
895 if (i < 0) return(i);
898 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
903 s->rwstate=SSL_NOTHING;
905 /* s->s3->rrec.type - is the type of record
906 * s->s3->rrec.data, - data
907 * s->s3->rrec.off, - offset into 'data' for next read
908 * s->s3->rrec.length, - number of bytes. */
911 /* get new packet if necessary */
912 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
914 ret=ssl3_get_record(s);
915 if (ret <= 0) return(ret);
918 /* we now have a packet which can be read and processed */
920 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
921 * reset by ssl3_get_finished */
922 && (rr->type != SSL3_RT_HANDSHAKE))
924 al=SSL_AD_UNEXPECTED_MESSAGE;
925 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
929 /* If the other end has shut down, throw anything we read away
930 * (even in 'peek' mode) */
931 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
934 s->rwstate=SSL_NOTHING;
939 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
941 /* make sure that we are not getting application data when we
942 * are doing a handshake for the first time */
943 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
944 (s->enc_read_ctx == NULL))
946 al=SSL_AD_UNEXPECTED_MESSAGE;
947 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
951 if (len <= 0) return(len);
953 if ((unsigned int)len > rr->length)
956 n = (unsigned int)len;
958 memcpy(buf,&(rr->data[rr->off]),n);
965 s->rstate=SSL_ST_READ_HEADER;
973 /* If we get here, then type != rr->type; if we have a handshake
974 * message, then it was unexpected (Hello Request or Client Hello). */
976 /* In case of record types for which we have 'fragment' storage,
977 * fill that so that we can process the data at a fixed place.
980 unsigned int dest_maxlen = 0;
981 unsigned char *dest = NULL;
982 unsigned int *dest_len = NULL;
984 if (rr->type == SSL3_RT_HANDSHAKE)
986 dest_maxlen = sizeof s->s3->handshake_fragment;
987 dest = s->s3->handshake_fragment;
988 dest_len = &s->s3->handshake_fragment_len;
990 else if (rr->type == SSL3_RT_ALERT)
992 dest_maxlen = sizeof s->s3->alert_fragment;
993 dest = s->s3->alert_fragment;
994 dest_len = &s->s3->alert_fragment_len;
999 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1001 n = rr->length; /* available bytes */
1003 /* now move 'n' bytes: */
1006 dest[(*dest_len)++] = rr->data[rr->off++];
1010 if (*dest_len < dest_maxlen)
1011 goto start; /* fragment was too small */
1015 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1016 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1017 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1019 /* If we are a client, check for an incoming 'Hello Request': */
1021 (s->s3->handshake_fragment_len >= 4) &&
1022 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1023 (s->session != NULL) && (s->session->cipher != NULL))
1025 s->s3->handshake_fragment_len = 0;
1027 if ((s->s3->handshake_fragment[1] != 0) ||
1028 (s->s3->handshake_fragment[2] != 0) ||
1029 (s->s3->handshake_fragment[3] != 0))
1031 al=SSL_AD_DECODE_ERROR;
1032 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1036 if (s->msg_callback)
1037 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1039 if (SSL_is_init_finished(s) &&
1040 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1041 !s->s3->renegotiate)
1043 ssl3_renegotiate(s);
1044 if (ssl3_renegotiate_check(s))
1046 i=s->handshake_func(s);
1047 if (i < 0) return(i);
1050 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1054 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1056 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1059 /* In the case where we try to read application data,
1060 * but we trigger an SSL handshake, we return -1 with
1061 * the retry option set. Otherwise renegotiation may
1062 * cause nasty problems in the blocking world */
1063 s->rwstate=SSL_READING;
1064 bio=SSL_get_rbio(s);
1065 BIO_clear_retry_flags(bio);
1066 BIO_set_retry_read(bio);
1072 /* we either finished a handshake or ignored the request,
1073 * now try again to obtain the (application) data we were asked for */
1077 if (s->s3->alert_fragment_len >= 2)
1079 int alert_level = s->s3->alert_fragment[0];
1080 int alert_descr = s->s3->alert_fragment[1];
1082 s->s3->alert_fragment_len = 0;
1084 if (s->msg_callback)
1085 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1087 if (s->info_callback != NULL)
1088 cb=s->info_callback;
1089 else if (s->ctx->info_callback != NULL)
1090 cb=s->ctx->info_callback;
1094 j = (alert_level << 8) | alert_descr;
1095 cb(s, SSL_CB_READ_ALERT, j);
1098 if (alert_level == 1) /* warning */
1100 s->s3->warn_alert = alert_descr;
1101 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1103 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1107 else if (alert_level == 2) /* fatal */
1111 s->rwstate=SSL_NOTHING;
1112 s->s3->fatal_alert = alert_descr;
1113 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1114 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1115 ERR_add_error_data(2,"SSL alert number ",tmp);
1116 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1117 SSL_CTX_remove_session(s->ctx,s->session);
1122 al=SSL_AD_ILLEGAL_PARAMETER;
1123 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1130 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1132 s->rwstate=SSL_NOTHING;
1137 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1139 /* 'Change Cipher Spec' is just a single byte, so we know
1140 * exactly what the record payload has to look like */
1141 if ( (rr->length != 1) || (rr->off != 0) ||
1142 (rr->data[0] != SSL3_MT_CCS))
1144 al=SSL_AD_ILLEGAL_PARAMETER;
1145 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1149 /* Check we have a cipher to change to */
1150 if (s->s3->tmp.new_cipher == NULL)
1152 al=SSL_AD_UNEXPECTED_MESSAGE;
1153 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1159 if (s->msg_callback)
1160 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1162 s->s3->change_cipher_spec=1;
1163 if (!ssl3_do_change_cipher_spec(s))
1169 /* Unexpected handshake message (Client Hello, or protocol violation) */
1170 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1172 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1173 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1175 #if 0 /* worked only because C operator preferences are not as expected (and
1176 * because this is not really needed for clients except for detecting
1177 * protocol violations): */
1178 s->state=SSL_ST_BEFORE|(s->server)
1182 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1186 i=s->handshake_func(s);
1187 if (i < 0) return(i);
1190 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1194 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1196 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1199 /* In the case where we try to read application data,
1200 * but we trigger an SSL handshake, we return -1 with
1201 * the retry option set. Otherwise renegotiation may
1202 * cause nasty problems in the blocking world */
1203 s->rwstate=SSL_READING;
1204 bio=SSL_get_rbio(s);
1205 BIO_clear_retry_flags(bio);
1206 BIO_set_retry_read(bio);
1216 #ifndef OPENSSL_NO_TLS
1217 /* TLS just ignores unknown message types */
1218 if (s->version == TLS1_VERSION)
1224 al=SSL_AD_UNEXPECTED_MESSAGE;
1225 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1227 case SSL3_RT_CHANGE_CIPHER_SPEC:
1229 case SSL3_RT_HANDSHAKE:
1230 /* we already handled all of these, with the possible exception
1231 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1232 * should not happen when type != rr->type */
1233 al=SSL_AD_UNEXPECTED_MESSAGE;
1234 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1236 case SSL3_RT_APPLICATION_DATA:
1237 /* At this point, we were expecting handshake data,
1238 * but have application data. If the library was
1239 * running inside ssl3_read() (i.e. in_read_app_data
1240 * is set) and it makes sense to read application data
1241 * at this point (session renegotiation not yet started),
1242 * we will indulge it.
1244 if (s->s3->in_read_app_data &&
1245 (s->s3->total_renegotiations != 0) &&
1247 (s->state & SSL_ST_CONNECT) &&
1248 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1249 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1251 (s->state & SSL_ST_ACCEPT) &&
1252 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1253 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1257 s->s3->in_read_app_data=2;
1262 al=SSL_AD_UNEXPECTED_MESSAGE;
1263 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1270 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1275 int ssl3_do_change_cipher_spec(SSL *s)
1281 if (s->state & SSL_ST_ACCEPT)
1282 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1284 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1286 if (s->s3->tmp.key_block == NULL)
1288 s->session->cipher=s->s3->tmp.new_cipher;
1289 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1292 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1295 /* we have to record the message digest at
1296 * this point so we can get it before we read
1297 * the finished message */
1298 if (s->state & SSL_ST_CONNECT)
1300 sender=s->method->ssl3_enc->server_finished_label;
1301 slen=s->method->ssl3_enc->server_finished_label_len;
1305 sender=s->method->ssl3_enc->client_finished_label;
1306 slen=s->method->ssl3_enc->client_finished_label_len;
1309 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1310 &(s->s3->finish_dgst1),
1311 &(s->s3->finish_dgst2),
1312 sender,slen,s->s3->tmp.peer_finish_md);
1317 void ssl3_send_alert(SSL *s, int level, int desc)
1319 /* Map tls/ssl alert value to correct one */
1320 desc=s->method->ssl3_enc->alert_value(desc);
1321 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1322 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1323 if (desc < 0) return;
1324 /* If a fatal one, remove from cache */
1325 if ((level == 2) && (s->session != NULL))
1326 SSL_CTX_remove_session(s->ctx,s->session);
1328 s->s3->alert_dispatch=1;
1329 s->s3->send_alert[0]=level;
1330 s->s3->send_alert[1]=desc;
1331 if (s->s3->wbuf.left == 0) /* data still being written out? */
1332 s->method->ssl_dispatch_alert(s);
1333 /* else data is still being written out, we will get written
1334 * some time in the future */
1337 int ssl3_dispatch_alert(SSL *s)
1340 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1342 s->s3->alert_dispatch=0;
1343 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1346 s->s3->alert_dispatch=1;
1350 /* Alert sent to BIO. If it is important, flush it now.
1351 * If the message does not get sent due to non-blocking IO,
1352 * we will not worry too much. */
1353 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1354 (void)BIO_flush(s->wbio);
1356 if (s->msg_callback)
1357 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1359 if (s->info_callback != NULL)
1360 cb=s->info_callback;
1361 else if (s->ctx->info_callback != NULL)
1362 cb=s->ctx->info_callback;
1366 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1367 cb(s,SSL_CB_WRITE_ALERT,j);