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openssl/ssl/s3_pkt.c

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/* ssl/s3_pkt.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/* ====================================================================
* Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#include <stdio.h>
#include <limits.h>
#include <errno.h>
#define USE_SOCKETS
#include "ssl_locl.h"
#include <openssl/evp.h>
#include <openssl/buffer.h>
#include <openssl/rand.h>
#ifndef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
# define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
#endif
#if defined(OPENSSL_SMALL_FOOTPRINT) || \
!( defined(AES_ASM) && ( \
defined(__x86_64) || defined(__x86_64__) || \
defined(_M_AMD64) || defined(_M_X64) || \
defined(__INTEL__) ) \
)
# undef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
# define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
#endif
static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
unsigned int len, int create_empty_fragment);
static int ssl3_get_record(SSL *s);
int ssl3_read_n(SSL *s, int n, int max, int extend)
{
/* If extend == 0, obtain new n-byte packet; if extend == 1, increase
* packet by another n bytes.
* The packet will be in the sub-array of s->s3->rbuf.buf specified
* by s->packet and s->packet_length.
* (If s->read_ahead is set, 'max' bytes may be stored in rbuf
* [plus s->packet_length bytes if extend == 1].)
*/
int i,len,left;
long align=0;
unsigned char *pkt;
SSL3_BUFFER *rb;
if (n <= 0) return n;
rb = &(s->s3->rbuf);
if (rb->buf == NULL)
if (!ssl3_setup_read_buffer(s))
return -1;
left = rb->left;
#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
#endif
if (!extend)
{
/* start with empty packet ... */
if (left == 0)
rb->offset = align;
else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
{
/* check if next packet length is large
* enough to justify payload alignment... */
pkt = rb->buf + rb->offset;
if (pkt[0] == SSL3_RT_APPLICATION_DATA
&& (pkt[3]<<8|pkt[4]) >= 128)
{
/* Note that even if packet is corrupted
* and its length field is insane, we can
* only be led to wrong decision about
* whether memmove will occur or not.
* Header values has no effect on memmove
* arguments and therefore no buffer
* overrun can be triggered. */
memmove (rb->buf+align,pkt,left);
rb->offset = align;
}
}
s->packet = rb->buf + rb->offset;
s->packet_length = 0;
/* ... now we can act as if 'extend' was set */
}
/* For DTLS/UDP reads should not span multiple packets
* because the read operation returns the whole packet
* at once (as long as it fits into the buffer). */
if (SSL_IS_DTLS(s))
{
if (left > 0 && n > left)
n = left;
}
/* if there is enough in the buffer from a previous read, take some */
if (left >= n)
{
s->packet_length+=n;
rb->left=left-n;
rb->offset+=n;
return(n);
}
/* else we need to read more data */
len = s->packet_length;
pkt = rb->buf+align;
/* Move any available bytes to front of buffer:
* 'len' bytes already pointed to by 'packet',
* 'left' extra ones at the end */
if (s->packet != pkt) /* len > 0 */
{
memmove(pkt, s->packet, len+left);
s->packet = pkt;
rb->offset = len + align;
}
if (n > (int)(rb->len - rb->offset)) /* does not happen */
{
SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
return -1;
}
if (!s->read_ahead)
/* ignore max parameter */
max = n;
else
{
if (max < n)
max = n;
if (max > (int)(rb->len - rb->offset))
max = rb->len - rb->offset;
}
while (left < n)
{
/* Now we have len+left bytes at the front of s->s3->rbuf.buf
* and need to read in more until we have len+n (up to
* len+max if possible) */
clear_sys_error();
if (s->rbio != NULL)
{
s->rwstate=SSL_READING;
i=BIO_read(s->rbio,pkt+len+left, max-left);
}
else
{
SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
i = -1;
}
if (i <= 0)
{
rb->left = left;
if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
!SSL_IS_DTLS(s))
if (len+left == 0)
ssl3_release_read_buffer(s);
return(i);
}
left+=i;
/* reads should *never* span multiple packets for DTLS because
* the underlying transport protocol is message oriented as opposed
* to byte oriented as in the TLS case. */
if (SSL_IS_DTLS(s))
{
if (n > left)
n = left; /* makes the while condition false */
}
}
/* done reading, now the book-keeping */
rb->offset += n;
rb->left = left - n;
s->packet_length += n;
s->rwstate=SSL_NOTHING;
return(n);
}
/* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will
* be processed per call to ssl3_get_record. Without this limit an attacker
* could send empty records at a faster rate than we can process and cause
* ssl3_get_record to loop forever. */
#define MAX_EMPTY_RECORDS 32
/* Call this to get a new input record.
* It will return <= 0 if more data is needed, normally due to an error
* or non-blocking IO.
* When it finishes, one packet has been decoded and can be found in
* ssl->s3->rrec.type - is the type of record
* ssl->s3->rrec.data, - data
* ssl->s3->rrec.length, - number of bytes
*/
/* used only by ssl3_read_bytes */
static int ssl3_get_record(SSL *s)
{
int ssl_major,ssl_minor,al;
int enc_err,n,i,ret= -1;
SSL3_RECORD *rr;
SSL_SESSION *sess;
unsigned char *p;
unsigned char md[EVP_MAX_MD_SIZE];
short version;
unsigned mac_size;
size_t extra;
unsigned empty_record_count = 0;
rr= &(s->s3->rrec);
sess=s->session;
if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
extra=SSL3_RT_MAX_EXTRA;
else
extra=0;
if (extra && !s->s3->init_extra)
{
/* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
* set after ssl3_setup_buffers() was done */
SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
return -1;
}
again:
/* check if we have the header */
if ( (s->rstate != SSL_ST_READ_BODY) ||
(s->packet_length < SSL3_RT_HEADER_LENGTH))
{
n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
if (n <= 0) return(n); /* error or non-blocking */
s->rstate=SSL_ST_READ_BODY;
p=s->packet;
if (s->msg_callback)
s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
/* Pull apart the header into the SSL3_RECORD */
rr->type= *(p++);
ssl_major= *(p++);
ssl_minor= *(p++);
version=(ssl_major<<8)|ssl_minor;
n2s(p,rr->length);
#if 0
fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
#endif
/* Lets check version */
if (!s->first_packet)
{
if (version != s->version)
{
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash)
/* Send back error using their minor version number :-) */
s->version = (unsigned short)version;
al=SSL_AD_PROTOCOL_VERSION;
goto f_err;
}
}
if ((version>>8) != SSL3_VERSION_MAJOR)
{
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
goto err;
}
if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
{
al=SSL_AD_RECORD_OVERFLOW;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
goto f_err;
}
/* now s->rstate == SSL_ST_READ_BODY */
}
/* s->rstate == SSL_ST_READ_BODY, get and decode the data */
if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
{
/* now s->packet_length == SSL3_RT_HEADER_LENGTH */
i=rr->length;
n=ssl3_read_n(s,i,i,1);
if (n <= 0) return(n); /* error or non-blocking io */
/* now n == rr->length,
* and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
}
s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
/* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
* and we have that many bytes in s->packet
*/
rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
/* ok, we can now read from 's->packet' data into 'rr'
* rr->input points at rr->length bytes, which
* need to be copied into rr->data by either
* the decryption or by the decompression
* When the data is 'copied' into the rr->data buffer,
* rr->input will be pointed at the new buffer */
/* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
* rr->length bytes of encrypted compressed stuff. */
/* check is not needed I believe */
if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
{
al=SSL_AD_RECORD_OVERFLOW;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
goto f_err;
}
/* decrypt in place in 'rr->input' */
rr->data=rr->input;
rr->orig_len=rr->length;
/* If in encrypt-then-mac mode calculate mac from encrypted record.
* All the details below are public so no timing details can leak.
*/
if (SSL_USE_ETM(s) && s->read_hash)
{
unsigned char *mac;
mac_size=EVP_MD_CTX_size(s->read_hash);
OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
if (rr->length < mac_size)
{
al=SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
goto f_err;
}
rr->length -= mac_size;
mac = rr->data + rr->length;
i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
if (i < 0 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
{
al=SSL_AD_BAD_RECORD_MAC;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
goto f_err;
}
}
enc_err = s->method->ssl3_enc->enc(s,0);
/* enc_err is:
* 0: (in non-constant time) if the record is publically invalid.
* 1: if the padding is valid
* -1: if the padding is invalid */
if (enc_err == 0)
{
al=SSL_AD_DECRYPTION_FAILED;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
goto f_err;
}
#ifdef TLS_DEBUG
printf("dec %d\n",rr->length);
{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
printf("\n");
#endif
/* r->length is now the compressed data plus mac */
if ((sess != NULL) &&
(s->enc_read_ctx != NULL) &&
(EVP_MD_CTX_md(s->read_hash) != NULL) && !SSL_USE_ETM(s))
{
/* s->read_hash != NULL => mac_size != -1 */
unsigned char *mac = NULL;
unsigned char mac_tmp[EVP_MAX_MD_SIZE];
mac_size=EVP_MD_CTX_size(s->read_hash);
OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
/* orig_len is the length of the record before any padding was
* removed. This is public information, as is the MAC in use,
* therefore we can safely process the record in a different
* amount of time if it's too short to possibly contain a MAC.
*/
if (rr->orig_len < mac_size ||
/* CBC records must have a padding length byte too. */
(EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
rr->orig_len < mac_size+1))
{
al=SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
goto f_err;
}
if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
{
/* We update the length so that the TLS header bytes
* can be constructed correctly but we need to extract
* the MAC in constant time from within the record,
* without leaking the contents of the padding bytes.
* */
mac = mac_tmp;
ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);
rr->length -= mac_size;
}
else
{
/* In this case there's no padding, so |rec->orig_len|
* equals |rec->length| and we checked that there's
* enough bytes for |mac_size| above. */
rr->length -= mac_size;
mac = &rr->data[rr->length];
}
i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
enc_err = -1;
if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
enc_err = -1;
}
if (enc_err < 0)
{
/* A separate 'decryption_failed' alert was introduced with TLS 1.0,
* SSL 3.0 only has 'bad_record_mac'. But unless a decryption
* failure is directly visible from the ciphertext anyway,
* we should not reveal which kind of error occurred -- this
* might become visible to an attacker (e.g. via a logfile) */
al=SSL_AD_BAD_RECORD_MAC;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
goto f_err;
}
/* r->length is now just compressed */
if (s->expand != NULL)
{
if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
{
al=SSL_AD_RECORD_OVERFLOW;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
goto f_err;
}
if (!ssl3_do_uncompress(s))
{
al=SSL_AD_DECOMPRESSION_FAILURE;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
goto f_err;
}
}
if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
{
al=SSL_AD_RECORD_OVERFLOW;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
goto f_err;
}
rr->off=0;
/* So at this point the following is true
* ssl->s3->rrec.type is the type of record
* ssl->s3->rrec.length == number of bytes in record
* ssl->s3->rrec.off == offset to first valid byte
* ssl->s3->rrec.data == where to take bytes from, increment
* after use :-).
*/
/* we have pulled in a full packet so zero things */
s->packet_length=0;
/* just read a 0 length packet */
if (rr->length == 0)
{
empty_record_count++;
if (empty_record_count > MAX_EMPTY_RECORDS)
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL);
goto f_err;
}
goto again;
}
#if 0
fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
#endif
return(1);
f_err:
ssl3_send_alert(s,SSL3_AL_FATAL,al);
err:
return(ret);
}
int ssl3_do_uncompress(SSL *ssl)
{
#ifndef OPENSSL_NO_COMP
int i;
SSL3_RECORD *rr;
rr= &(ssl->s3->rrec);
i=COMP_expand_block(ssl->expand,rr->comp,
SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
if (i < 0)
return(0);
else
rr->length=i;
rr->data=rr->comp;
#endif
return(1);
}
int ssl3_do_compress(SSL *ssl)
{
#ifndef OPENSSL_NO_COMP
int i;
SSL3_RECORD *wr;
wr= &(ssl->s3->wrec);
i=COMP_compress_block(ssl->compress,wr->data,
SSL3_RT_MAX_COMPRESSED_LENGTH,
wr->input,(int)wr->length);
if (i < 0)
return(0);
else
wr->length=i;
wr->input=wr->data;
#endif
return(1);
}
/* Call this to write data in records of type 'type'
* It will return <= 0 if not all data has been sent or non-blocking IO.
*/
int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
{
const unsigned char *buf=buf_;
int tot;
unsigned int n,nw;
#if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
unsigned int max_send_fragment;
#endif
SSL3_BUFFER *wb=&(s->s3->wbuf);
int i;
unsigned int u_len = (unsigned int)len;
if (len < 0)
{
SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_NEGATIVE_LENGTH);
return -1;
}
s->rwstate=SSL_NOTHING;
OPENSSL_assert(s->s3->wnum <= INT_MAX);
tot=s->s3->wnum;
s->s3->wnum=0;
if (SSL_in_init(s) && !s->in_handshake)
{
i=s->handshake_func(s);
if (i < 0) return(i);
if (i == 0)
{
SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
return -1;
}
}
/* ensure that if we end up with a smaller value of data to write
* out than the the original len from a write which didn't complete
* for non-blocking I/O and also somehow ended up avoiding
* the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
* it must never be possible to end up with (len-tot) as a large
* number that will then promptly send beyond the end of the users
* buffer ... so we trap and report the error in a way the user
* will notice
*/
if (len < tot)
{
SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
return(-1);
}
/* first check if there is a SSL3_BUFFER still being written
* out. This will happen with non blocking IO */
if (wb->left != 0)
{
i = ssl3_write_pending(s,type,&buf[tot],s->s3->wpend_tot);
if (i<=0)
{
/* XXX should we ssl3_release_write_buffer if i<0? */
s->s3->wnum=tot;
return i;
}
tot += i; /* this might be last fragment */
}
#if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
/*
* Depending on platform multi-block can deliver several *times*
* better performance. Downside is that it has to allocate
* jumbo buffer to accomodate up to 8 records, but the
* compromise is considered worthy.
*/
if (type==SSL3_RT_APPLICATION_DATA &&
u_len >= 4*(max_send_fragment=s->max_send_fragment) &&
s->compress==NULL && s->msg_callback==NULL &&
!SSL_USE_ETM(s) && SSL_USE_EXPLICIT_IV(s) &&
EVP_CIPHER_flags(s->enc_write_ctx->cipher)&EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK)
{
unsigned char aad[13];
EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param;
int packlen;
/* minimize address aliasing conflicts */
if ((max_send_fragment&0xfff) == 0)
max_send_fragment -= 512;
if (tot==0 || wb->buf==NULL) /* allocate jumbo buffer */
{
ssl3_release_write_buffer(s);
packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
EVP_CTRL_TLS1_1_MULTIBLOCK_MAX_BUFSIZE,
max_send_fragment,NULL);
if (u_len >= 8*max_send_fragment) packlen *= 8;
else packlen *= 4;
wb->buf=OPENSSL_malloc(packlen);
wb->len=packlen;
}
else if (tot==len) /* done? */
{
OPENSSL_free(wb->buf); /* free jumbo buffer */
wb->buf = NULL;
return tot;
}
n=(len-tot);
for (;;)
{
if (n < 4*max_send_fragment)
{
OPENSSL_free(wb->buf); /* free jumbo buffer */
wb->buf = NULL;
break;
}
if (s->s3->alert_dispatch)
{
i=s->method->ssl_dispatch_alert(s);
if (i <= 0)
{
s->s3->wnum=tot;
return i;
}
}
if (n >= 8*max_send_fragment)
nw = max_send_fragment*(mb_param.interleave=8);
else
nw = max_send_fragment*(mb_param.interleave=4);
memcpy(aad,s->s3->write_sequence,8);
aad[8]=type;
aad[9]=(unsigned char)(s->version>>8);
aad[10]=(unsigned char)(s->version);
aad[11]=0;
aad[12]=0;
mb_param.out = NULL;
mb_param.inp = aad;
mb_param.len = nw;
packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
EVP_CTRL_TLS1_1_MULTIBLOCK_AAD,
sizeof(mb_param),&mb_param);
if (packlen<=0 || packlen>(int)wb->len) /* never happens */
{
OPENSSL_free(wb->buf); /* free jumbo buffer */
wb->buf = NULL;
break;
}
mb_param.out = wb->buf;
mb_param.inp = &buf[tot];
mb_param.len = nw;
if (EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT,
sizeof(mb_param),&mb_param)<=0)
return -1;
s->s3->write_sequence[7] += mb_param.interleave;
if (s->s3->write_sequence[7] < mb_param.interleave)
{
int j=6;
while (j>=0 && (++s->s3->write_sequence[j--])==0) ;
}
wb->offset = 0;
wb->left = packlen;
s->s3->wpend_tot = nw;
s->s3->wpend_buf = &buf[tot];
s->s3->wpend_type= type;
s->s3->wpend_ret = nw;
i = ssl3_write_pending(s,type,&buf[tot],nw);
if (i<=0)
{
if (i<0)
{
OPENSSL_free(wb->buf);
wb->buf = NULL;
}
s->s3->wnum=tot;
return i;
}
if (i==(int)n)
{
OPENSSL_free(wb->buf); /* free jumbo buffer */
wb->buf = NULL;
return tot+i;
}
n-=i;
tot+=i;
}
}
else
#endif
if (tot==len) /* done? */
{
if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
!SSL_IS_DTLS(s))
ssl3_release_write_buffer(s);
return tot;
}
n=(len-tot);
for (;;)
{
if (n > s->max_send_fragment)
nw=s->max_send_fragment;
else
nw=n;
i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
if (i <= 0)
{
/* XXX should we ssl3_release_write_buffer if i<0? */
s->s3->wnum=tot;
return i;
}
if ((i == (int)n) ||
(type == SSL3_RT_APPLICATION_DATA &&
(s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
{
/* next chunk of data should get another prepended empty fragment
* in ciphersuites with known-IV weakness: */
s->s3->empty_fragment_done = 0;
if ((i==(int)n) && s->mode & SSL_MODE_RELEASE_BUFFERS &&
!SSL_IS_DTLS(s))
ssl3_release_write_buffer(s);
return tot+i;
}
n-=i;
tot+=i;
}
}
static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
unsigned int len, int create_empty_fragment)
{
unsigned char *p,*plen;
int i,mac_size,clear=0;
int prefix_len=0;
int eivlen;
long align=0;
SSL3_RECORD *wr;
SSL3_BUFFER *wb=&(s->s3->wbuf);
SSL_SESSION *sess;
/* first check if there is a SSL3_BUFFER still being written
* out. This will happen with non blocking IO */
if (wb->left != 0)
return(ssl3_write_pending(s,type,buf,len));
/* If we have an alert to send, lets send it */
if (s->s3->alert_dispatch)
{
i=s->method->ssl_dispatch_alert(s);
if (i <= 0)
return(i);
/* if it went, fall through and send more stuff */
}
if (wb->buf == NULL)
if (!ssl3_setup_write_buffer(s))
return -1;
if (len == 0 && !create_empty_fragment)
return 0;
wr= &(s->s3->wrec);
sess=s->session;
if ( (sess == NULL) ||
(s->enc_write_ctx == NULL) ||
(EVP_MD_CTX_md(s->write_hash) == NULL))
{
#if 1
clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */
#else
clear=1;
#endif
mac_size=0;
}
else
{
mac_size=EVP_MD_CTX_size(s->write_hash);
if (mac_size < 0)
goto err;
}
#if 0 && !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
if (type==SSL3_RT_APPLICATION_DATA && s->compress==NULL &&
!SSL_USE_ETM(s) && SSL_USE_EXPLICIT_IV(s) && /*!SSL_IS_DTLS(s) &&*/
EVP_CIPHER_flags(s->enc_write_ctx->cipher)&EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK)
do {
unsigned char aad[13];
EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param = {NULL,aad,sizeof(aad),0};
int packlen;
memcpy(aad,s->s3->write_sequence,8);
aad[8]=type;
aad[9]=(unsigned char)(s->version>>8);
aad[10]=(unsigned char)(s->version);
aad[11]=(unsigned char)(len>>8);
aad[12]=(unsigned char)len;
packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
EVP_CTRL_TLS1_1_MULTIBLOCK_AAD,
sizeof(mb_param),&mb_param);
if (packlen==0 || packlen > wb->len) break;
mb_param.out = wb->buf;
mb_param.inp = buf;
mb_param.len = len;
EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT,
sizeof(mb_param),&mb_param);
s->s3->write_sequence[7] += mb_param.interleave;
if (s->s3->write_sequence[7] < mb_param.interleave)
{
int j=6;
while (j>=0 && (++s->s3->write_sequence[j--])==0) ;
}
wb->offset=0;
wb->left = packlen;
/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
s->s3->wpend_tot=len;
s->s3->wpend_buf=buf;
s->s3->wpend_type=type;
s->s3->wpend_ret=len;
/* we now just need to write the buffer */
return ssl3_write_pending(s,type,buf,len);
} while (0);
#endif
/* 'create_empty_fragment' is true only when this function calls itself */
if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
{
/* countermeasure against known-IV weakness in CBC ciphersuites
* (see http://www.openssl.org/~bodo/tls-cbc.txt) */
if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
{
/* recursive function call with 'create_empty_fragment' set;
* this prepares and buffers the data for an empty fragment
* (these 'prefix_len' bytes are sent out later
* together with the actual payload) */
prefix_len = do_ssl3_write(s, type, buf, 0, 1);
if (prefix_len <= 0)
goto err;
if (prefix_len >
(SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
{
/* insufficient space */
SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
goto err;
}
}
s->s3->empty_fragment_done = 1;
}
if (create_empty_fragment)
{
#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
/* extra fragment would be couple of cipher blocks,
* which would be multiple of SSL3_ALIGN_PAYLOAD, so
* if we want to align the real payload, then we can
* just pretent we simply have two headers. */
align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
#endif
p = wb->buf + align;
wb->offset = align;
}
else if (prefix_len)
{
p = wb->buf + wb->offset + prefix_len;
}
else
{
#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
#endif
p = wb->buf + align;
wb->offset = align;
}
/* write the header */
*(p++)=type&0xff;
wr->type=type;
*(p++)=(s->version>>8);
/* Some servers hang if iniatial client hello is larger than 256
* bytes and record version number > TLS 1.0
*/
if (s->state == SSL3_ST_CW_CLNT_HELLO_B
&& !s->renegotiate
&& TLS1_get_version(s) > TLS1_VERSION)
*(p++) = 0x1;
else
*(p++)=s->version&0xff;
/* field where we are to write out packet length */
plen=p;
p+=2;
/* Explicit IV length, block ciphers appropriate version flag */
if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s))
{
int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
if (mode == EVP_CIPH_CBC_MODE)
{
eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
if (eivlen <= 1)
eivlen = 0;
}
/* Need explicit part of IV for GCM mode */
else if (mode == EVP_CIPH_GCM_MODE)
eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
else
eivlen = 0;
}
else
eivlen = 0;
/* lets setup the record stuff. */
wr->data=p + eivlen;
wr->length=(int)len;
wr->input=(unsigned char *)buf;
/* we now 'read' from wr->input, wr->length bytes into
* wr->data */
/* first we compress */
if (s->compress != NULL)
{
if (!ssl3_do_compress(s))
{
SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
goto err;
}
}
else
{
memcpy(wr->data,wr->input,wr->length);
wr->input=wr->data;
}
/* we should still have the output to wr->data and the input
* from wr->input. Length should be wr->length.
* wr->data still points in the wb->buf */
if (!SSL_USE_ETM(s) && mac_size != 0)
{
if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
goto err;
wr->length+=mac_size;
}
wr->input=p;
wr->data=p;
if (eivlen)
{
/* if (RAND_pseudo_bytes(p, eivlen) <= 0)
goto err; */
wr->length += eivlen;
}
if(s->method->ssl3_enc->enc(s,1)<1) goto err;
if (SSL_USE_ETM(s) && mac_size != 0)
{
if (s->method->ssl3_enc->mac(s,p + wr->length,1) < 0)
goto err;
wr->length+=mac_size;
}
/* record length after mac and block padding */
s2n(wr->length,plen);
if (s->msg_callback)
s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
/* we should now have
* wr->data pointing to the encrypted data, which is
* wr->length long */
wr->type=type; /* not needed but helps for debugging */
wr->length+=SSL3_RT_HEADER_LENGTH;
if (create_empty_fragment)
{
/* we are in a recursive call;
* just return the length, don't write out anything here
*/
return wr->length;
}
/* now let's set up wb */
wb->left = prefix_len + wr->length;
/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
s->s3->wpend_tot=len;
s->s3->wpend_buf=buf;
s->s3->wpend_type=type;
s->s3->wpend_ret=len;
/* we now just need to write the buffer */
return ssl3_write_pending(s,type,buf,len);
err:
return -1;
}
/* if s->s3->wbuf.left != 0, we need to call this */
int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
unsigned int len)
{
int i;
SSL3_BUFFER *wb=&(s->s3->wbuf);
/* XXXX */
if ((s->s3->wpend_tot > (int)len)
|| ((s->s3->wpend_buf != buf) &&
!(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
|| (s->s3->wpend_type != type))
{
SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
return(-1);
}
for (;;)
{
clear_sys_error();
if (s->wbio != NULL)
{
s->rwstate=SSL_WRITING;
i=BIO_write(s->wbio,
(char *)&(wb->buf[wb->offset]),
(unsigned int)wb->left);
}
else
{
SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
i= -1;
}
if (i == wb->left)
{
wb->left=0;
wb->offset+=i;
s->rwstate=SSL_NOTHING;
return(s->s3->wpend_ret);
}
else if (i <= 0) {
if (s->version == DTLS1_VERSION ||
s->version == DTLS1_BAD_VER) {
/* For DTLS, just drop it. That's kind of the whole
point in using a datagram service */
wb->left = 0;
}
return(i);
}
wb->offset+=i;
wb->left-=i;
}
}
/* Return up to 'len' payload bytes received in 'type' records.
* 'type' is one of the following:
*
* - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
* - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
* - 0 (during a shutdown, no data has to be returned)
*
* If we don't have stored data to work from, read a SSL/TLS record first
* (possibly multiple records if we still don't have anything to return).
*
* This function must handle any surprises the peer may have for us, such as
* Alert records (e.g. close_notify), ChangeCipherSpec records (not really
* a surprise, but handled as if it were), or renegotiation requests.
* Also if record payloads contain fragments too small to process, we store
* them until there is enough for the respective protocol (the record protocol
* may use arbitrary fragmentation and even interleaving):
* Change cipher spec protocol
* just 1 byte needed, no need for keeping anything stored
* Alert protocol
* 2 bytes needed (AlertLevel, AlertDescription)
* Handshake protocol
* 4 bytes needed (HandshakeType, uint24 length) -- we just have
* to detect unexpected Client Hello and Hello Request messages
* here, anything else is handled by higher layers
* Application data protocol
* none of our business
*/
int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
{
int al,i,j,ret;
unsigned int n;
SSL3_RECORD *rr;
void (*cb)(const SSL *ssl,int type2,int val)=NULL;
if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
if (!ssl3_setup_read_buffer(s))
return(-1);
if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) ||
(peek && (type != SSL3_RT_APPLICATION_DATA)))
{
SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
return -1;
}
if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
/* (partially) satisfy request from storage */
{
unsigned char *src = s->s3->handshake_fragment;
unsigned char *dst = buf;
unsigned int k;
/* peek == 0 */
n = 0;
while ((len > 0) && (s->s3->handshake_fragment_len > 0))
{
*dst++ = *src++;
len--; s->s3->handshake_fragment_len--;
n++;
}
/* move any remaining fragment bytes: */
for (k = 0; k < s->s3->handshake_fragment_len; k++)
s->s3->handshake_fragment[k] = *src++;
return n;
}
/* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
if (!s->in_handshake && SSL_in_init(s))
{
/* type == SSL3_RT_APPLICATION_DATA */
i=s->handshake_func(s);
if (i < 0) return(i);
if (i == 0)
{
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
return(-1);
}
}
start:
s->rwstate=SSL_NOTHING;
/* s->s3->rrec.type - is the type of record
* s->s3->rrec.data, - data
* s->s3->rrec.off, - offset into 'data' for next read
* s->s3->rrec.length, - number of bytes. */
rr = &(s->s3->rrec);
/* get new packet if necessary */
if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
{
ret=ssl3_get_record(s);
if (ret <= 0) return(ret);
}
/* we now have a packet which can be read and processed */
if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
* reset by ssl3_get_finished */
&& (rr->type != SSL3_RT_HANDSHAKE))
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
goto f_err;
}
/* If the other end has shut down, throw anything we read away
* (even in 'peek' mode) */
if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
{
rr->length=0;
s->rwstate=SSL_NOTHING;
return(0);
}
if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
{
/* make sure that we are not getting application data when we
* are doing a handshake for the first time */
if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
(s->enc_read_ctx == NULL))
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
goto f_err;
}
if (len <= 0) return(len);
if ((unsigned int)len > rr->length)
n = rr->length;
else
n = (unsigned int)len;
memcpy(buf,&(rr->data[rr->off]),n);
if (!peek)
{
rr->length-=n;
rr->off+=n;
if (rr->length == 0)
{
s->rstate=SSL_ST_READ_HEADER;
rr->off=0;
if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0)
ssl3_release_read_buffer(s);
}
}
return(n);
}
/* If we get here, then type != rr->type; if we have a handshake
* message, then it was unexpected (Hello Request or Client Hello). */
/* In case of record types for which we have 'fragment' storage,
* fill that so that we can process the data at a fixed place.
*/
{
unsigned int dest_maxlen = 0;
unsigned char *dest = NULL;
unsigned int *dest_len = NULL;
if (rr->type == SSL3_RT_HANDSHAKE)
{
dest_maxlen = sizeof s->s3->handshake_fragment;
dest = s->s3->handshake_fragment;
dest_len = &s->s3->handshake_fragment_len;
}
else if (rr->type == SSL3_RT_ALERT)
{
dest_maxlen = sizeof s->s3->alert_fragment;
dest = s->s3->alert_fragment;
dest_len = &s->s3->alert_fragment_len;
}
#ifndef OPENSSL_NO_HEARTBEATS
else if (rr->type == TLS1_RT_HEARTBEAT)
{
tls1_process_heartbeat(s);
/* Exit and notify application to read again */
rr->length = 0;
s->rwstate=SSL_READING;
BIO_clear_retry_flags(SSL_get_rbio(s));
BIO_set_retry_read(SSL_get_rbio(s));
return(-1);
}
#endif
if (dest_maxlen > 0)
{
n = dest_maxlen - *dest_len; /* available space in 'dest' */
if (rr->length < n)
n = rr->length; /* available bytes */
/* now move 'n' bytes: */
while (n-- > 0)
{
dest[(*dest_len)++] = rr->data[rr->off++];
rr->length--;
}
if (*dest_len < dest_maxlen)
goto start; /* fragment was too small */
}
}
/* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
* s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
* (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
/* If we are a client, check for an incoming 'Hello Request': */
if ((!s->server) &&
(s->s3->handshake_fragment_len >= 4) &&
(s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
(s->session != NULL) && (s->session->cipher != NULL))
{
s->s3->handshake_fragment_len = 0;
if ((s->s3->handshake_fragment[1] != 0) ||
(s->s3->handshake_fragment[2] != 0) ||
(s->s3->handshake_fragment[3] != 0))
{
al=SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
goto f_err;
}
if (s->msg_callback)
s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
if (SSL_is_init_finished(s) &&
!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
!s->s3->renegotiate)
{
ssl3_renegotiate(s);
if (ssl3_renegotiate_check(s))
{
i=s->handshake_func(s);
if (i < 0) return(i);
if (i == 0)
{
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
return(-1);
}
if (!(s->mode & SSL_MODE_AUTO_RETRY))
{
if (s->s3->rbuf.left == 0) /* no read-ahead left? */
{
BIO *bio;
/* In the case where we try to read application data,
* but we trigger an SSL handshake, we return -1 with
* the retry option set. Otherwise renegotiation may
* cause nasty problems in the blocking world */
s->rwstate=SSL_READING;
bio=SSL_get_rbio(s);
BIO_clear_retry_flags(bio);
BIO_set_retry_read(bio);
return(-1);
}
}
}
}
/* we either finished a handshake or ignored the request,
* now try again to obtain the (application) data we were asked for */
goto start;
}
/* If we are a server and get a client hello when renegotiation isn't
* allowed send back a no renegotiation alert and carry on.
* WARNING: experimental code, needs reviewing (steve)
*/
if (s->server &&
SSL_is_init_finished(s) &&
!s->s3->send_connection_binding &&
(s->version > SSL3_VERSION) &&
(s->s3->handshake_fragment_len >= 4) &&
(s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
(s->session != NULL) && (s->session->cipher != NULL) &&
!(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
{
/*s->s3->handshake_fragment_len = 0;*/
rr->length = 0;
ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
goto start;
}
if (s->s3->alert_fragment_len >= 2)
{
int alert_level = s->s3->alert_fragment[0];
int alert_descr = s->s3->alert_fragment[1];
s->s3->alert_fragment_len = 0;
if (s->msg_callback)
s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
if (s->info_callback != NULL)
cb=s->info_callback;
else if (s->ctx->info_callback != NULL)
cb=s->ctx->info_callback;
if (cb != NULL)
{
j = (alert_level << 8) | alert_descr;
cb(s, SSL_CB_READ_ALERT, j);
}
if (alert_level == 1) /* warning */
{
s->s3->warn_alert = alert_descr;
if (alert_descr == SSL_AD_CLOSE_NOTIFY)
{
s->shutdown |= SSL_RECEIVED_SHUTDOWN;
return(0);
}
/* This is a warning but we receive it if we requested
* renegotiation and the peer denied it. Terminate with
* a fatal alert because if application tried to
* renegotiatie it presumably had a good reason and
* expects it to succeed.
*
* In future we might have a renegotiation where we
* don't care if the peer refused it where we carry on.
*/
else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
{
al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
goto f_err;
}
#ifdef SSL_AD_MISSING_SRP_USERNAME
else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
return(0);
#endif
}
else if (alert_level == 2) /* fatal */
{
char tmp[16];
s->rwstate=SSL_NOTHING;
s->s3->fatal_alert = alert_descr;
SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
ERR_add_error_data(2,"SSL alert number ",tmp);
s->shutdown|=SSL_RECEIVED_SHUTDOWN;
SSL_CTX_remove_session(s->ctx,s->session);
return(0);
}
else
{
al=SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
goto f_err;
}
goto start;
}
if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
{
s->rwstate=SSL_NOTHING;
rr->length=0;
return(0);
}
if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
{
/* 'Change Cipher Spec' is just a single byte, so we know
* exactly what the record payload has to look like */
if ( (rr->length != 1) || (rr->off != 0) ||
(rr->data[0] != SSL3_MT_CCS))
{
al=SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
goto f_err;
}
/* Check we have a cipher to change to */
if (s->s3->tmp.new_cipher == NULL)
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
goto f_err;
}
if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
goto f_err;
}
s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
rr->length=0;
if (s->msg_callback)
s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
s->s3->change_cipher_spec=1;
if (!ssl3_do_change_cipher_spec(s))
goto err;
else
goto start;
}
/* Unexpected handshake message (Client Hello, or protocol violation) */
if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
{
if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
{
#if 0 /* worked only because C operator preferences are not as expected (and
* because this is not really needed for clients except for detecting
* protocol violations): */
s->state=SSL_ST_BEFORE|(s->server)
?SSL_ST_ACCEPT
:SSL_ST_CONNECT;
#else
s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
#endif
s->renegotiate=1;
s->new_session=1;
}
i=s->handshake_func(s);
if (i < 0) return(i);
if (i == 0)
{
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
return(-1);
}
if (!(s->mode & SSL_MODE_AUTO_RETRY))
{
if (s->s3->rbuf.left == 0) /* no read-ahead left? */
{
BIO *bio;
/* In the case where we try to read application data,
* but we trigger an SSL handshake, we return -1 with
* the retry option set. Otherwise renegotiation may
* cause nasty problems in the blocking world */
s->rwstate=SSL_READING;
bio=SSL_get_rbio(s);
BIO_clear_retry_flags(bio);
BIO_set_retry_read(bio);
return(-1);
}
}
goto start;
}
switch (rr->type)
{
default:
#ifndef OPENSSL_NO_TLS
/* TLS up to v1.1 just ignores unknown message types:
* TLS v1.2 give an unexpected message alert.
*/
if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
{
rr->length = 0;
goto start;
}
#endif
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
goto f_err;
case SSL3_RT_CHANGE_CIPHER_SPEC:
case SSL3_RT_ALERT:
case SSL3_RT_HANDSHAKE:
/* we already handled all of these, with the possible exception
* of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
* should not happen when type != rr->type */
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
goto f_err;
case SSL3_RT_APPLICATION_DATA:
/* At this point, we were expecting handshake data,
* but have application data. If the library was
* running inside ssl3_read() (i.e. in_read_app_data
* is set) and it makes sense to read application data
* at this point (session renegotiation not yet started),
* we will indulge it.
*/
if (s->s3->in_read_app_data &&
(s->s3->total_renegotiations != 0) &&
((
(s->state & SSL_ST_CONNECT) &&
(s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
(s->state <= SSL3_ST_CR_SRVR_HELLO_A)
) || (
(s->state & SSL_ST_ACCEPT) &&
(s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
(s->state >= SSL3_ST_SR_CLNT_HELLO_A)
)
))
{
s->s3->in_read_app_data=2;
return(-1);
}
else
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
goto f_err;
}
}
/* not reached */
f_err:
ssl3_send_alert(s,SSL3_AL_FATAL,al);
err:
return(-1);
}
int ssl3_do_change_cipher_spec(SSL *s)
{
int i;
const char *sender;
int slen;
if (s->state & SSL_ST_ACCEPT)
i=SSL3_CHANGE_CIPHER_SERVER_READ;
else
i=SSL3_CHANGE_CIPHER_CLIENT_READ;
if (s->s3->tmp.key_block == NULL)
{
if (s->session == NULL || s->session->master_key_length == 0)
{
/* might happen if dtls1_read_bytes() calls this */
SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
return (0);
}
s->session->cipher=s->s3->tmp.new_cipher;
if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
}
if (!s->method->ssl3_enc->change_cipher_state(s,i))
return(0);
/* we have to record the message digest at
* this point so we can get it before we read
* the finished message */
if (s->state & SSL_ST_CONNECT)
{
sender=s->method->ssl3_enc->server_finished_label;
slen=s->method->ssl3_enc->server_finished_label_len;
}
else
{
sender=s->method->ssl3_enc->client_finished_label;
slen=s->method->ssl3_enc->client_finished_label_len;
}
i = s->method->ssl3_enc->final_finish_mac(s,
sender,slen,s->s3->tmp.peer_finish_md);
if (i == 0)
{
SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
return 0;
}
s->s3->tmp.peer_finish_md_len = i;
return(1);
}
int ssl3_send_alert(SSL *s, int level, int desc)
{
/* Map tls/ssl alert value to correct one */
desc=s->method->ssl3_enc->alert_value(desc);
if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
if (desc < 0) return -1;
/* If a fatal one, remove from cache */
if ((level == SSL3_AL_FATAL) && (s->session != NULL))
SSL_CTX_remove_session(s->ctx,s->session);
s->s3->alert_dispatch=1;
s->s3->send_alert[0]=level;
s->s3->send_alert[1]=desc;
if (s->s3->wbuf.left == 0) /* data still being written out? */
return s->method->ssl_dispatch_alert(s);
/* else data is still being written out, we will get written
* some time in the future */
return -1;
}
int ssl3_dispatch_alert(SSL *s)
{
int i,j;
void (*cb)(const SSL *ssl,int type,int val)=NULL;
s->s3->alert_dispatch=0;
i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
if (i <= 0)
{
s->s3->alert_dispatch=1;
}
else
{
/* Alert sent to BIO. If it is important, flush it now.
* If the message does not get sent due to non-blocking IO,
* we will not worry too much. */
if (s->s3->send_alert[0] == SSL3_AL_FATAL)
(void)BIO_flush(s->wbio);
if (s->msg_callback)
s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
if (s->info_callback != NULL)
cb=s->info_callback;
else if (s->ctx->info_callback != NULL)
cb=s->ctx->info_callback;
if (cb != NULL)
{
j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
cb(s,SSL_CB_WRITE_ALERT,j);
}
}
return(i);
}
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