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yuzu/externals/libressl/ssl/ssl_pkt.c

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/* $OpenBSD: ssl_pkt.c,v 1.31 2020/08/30 15:40:20 jsing Exp $ */
/* 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 <errno.h>
#include <stdio.h>
#include "ssl_locl.h"
#include <openssl/buffer.h>
#include <openssl/evp.h>
#include "bytestring.h"
static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
unsigned int len);
static int ssl3_get_record(SSL *s);
/*
* Force a WANT_READ return for certain error conditions where
* we don't want to spin internally.
*/
static void
ssl_force_want_read(SSL *s)
{
BIO * bio;
bio = SSL_get_rbio(s);
BIO_clear_retry_flags(bio);
BIO_set_retry_read(bio);
s->internal->rwstate = SSL_READING;
}
/*
* 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 S3I(s)->rbuf.buf specified
* by s->internal->packet and s->internal->packet_length.
* (If s->internal->read_ahead is set, 'max' bytes may be stored in rbuf
* [plus s->internal->packet_length bytes if extend == 1].)
*/
static int
ssl3_read_n(SSL *s, int n, int max, int extend)
{
int i, len, left;
size_t align;
unsigned char *pkt;
SSL3_BUFFER_INTERNAL *rb;
if (n <= 0)
return n;
rb = &(S3I(s)->rbuf);
if (rb->buf == NULL)
if (!ssl3_setup_read_buffer(s))
return -1;
left = rb->left;
align = (size_t)rb->buf + SSL3_RT_HEADER_LENGTH;
align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
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->internal->packet = rb->buf + rb->offset;
s->internal->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->internal->packet_length += n;
rb->left = left - n;
rb->offset += n;
return (n);
}
/* else we need to read more data */
len = s->internal->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->internal->packet != pkt) {
/* len > 0 */
memmove(pkt, s->internal->packet, len + left);
s->internal->packet = pkt;
rb->offset = len + align;
}
if (n > (int)(rb->len - rb->offset)) {
/* does not happen */
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if (!s->internal->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 S3I(s)->rbuf.buf
* and need to read in more until we have len+n (up to
* len+max if possible) */
errno = 0;
if (s->rbio != NULL) {
s->internal->rwstate = SSL_READING;
i = BIO_read(s->rbio, pkt + len + left, max - left);
} else {
SSLerror(s, SSL_R_READ_BIO_NOT_SET);
i = -1;
}
if (i <= 0) {
rb->left = left;
if (s->internal->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->internal->packet_length += n;
s->internal->rwstate = SSL_NOTHING;
return (n);
}
int
ssl3_packet_read(SSL *s, int plen)
{
int n;
n = ssl3_read_n(s, plen, S3I(s)->rbuf.len, 0);
if (n <= 0)
return n;
if (s->internal->packet_length < plen)
return s->internal->packet_length;
return plen;
}
int
ssl3_packet_extend(SSL *s, int plen)
{
int rlen, n;
if (s->internal->packet_length >= plen)
return plen;
rlen = plen - s->internal->packet_length;
n = ssl3_read_n(s, rlen, rlen, 1);
if (n <= 0)
return n;
if (s->internal->packet_length < plen)
return s->internal->packet_length;
return plen;
}
/* 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->internal->rrec.type - is the type of record
* ssl->s3->internal->rrec.data, - data
* ssl->s3->internal->rrec.length, - number of bytes
*/
/* used only by ssl3_read_bytes */
static int
ssl3_get_record(SSL *s)
{
int al;
int enc_err, n, i, ret = -1;
SSL3_RECORD_INTERNAL *rr;
SSL_SESSION *sess;
unsigned char md[EVP_MAX_MD_SIZE];
unsigned int mac_size, orig_len;
rr = &(S3I(s)->rrec);
sess = s->session;
again:
/* check if we have the header */
if ((s->internal->rstate != SSL_ST_READ_BODY) ||
(s->internal->packet_length < SSL3_RT_HEADER_LENGTH)) {
CBS header;
uint16_t len, ssl_version;
uint8_t type;
n = ssl3_packet_read(s, SSL3_RT_HEADER_LENGTH);
if (n <= 0)
return (n);
s->internal->mac_packet = 1;
s->internal->rstate = SSL_ST_READ_BODY;
if (s->server && s->internal->first_packet) {
if ((ret = ssl_server_legacy_first_packet(s)) != 1)
return (ret);
ret = -1;
}
CBS_init(&header, s->internal->packet, SSL3_RT_HEADER_LENGTH);
/* Pull apart the header into the SSL3_RECORD_INTERNAL */
if (!CBS_get_u8(&header, &type) ||
!CBS_get_u16(&header, &ssl_version) ||
!CBS_get_u16(&header, &len)) {
SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
goto err;
}
rr->type = type;
rr->length = len;
/* Lets check version */
if (!s->internal->first_packet && ssl_version != s->version) {
SSLerror(s, SSL_R_WRONG_VERSION_NUMBER);
if ((s->version & 0xFF00) == (ssl_version & 0xFF00) &&
!s->internal->enc_write_ctx && !s->internal->write_hash)
/* Send back error using their minor version number :-) */
s->version = ssl_version;
al = SSL_AD_PROTOCOL_VERSION;
goto f_err;
}
if ((ssl_version >> 8) != SSL3_VERSION_MAJOR) {
SSLerror(s, SSL_R_WRONG_VERSION_NUMBER);
goto err;
}
if (rr->length > S3I(s)->rbuf.len - SSL3_RT_HEADER_LENGTH) {
al = SSL_AD_RECORD_OVERFLOW;
SSLerror(s, SSL_R_PACKET_LENGTH_TOO_LONG);
goto f_err;
}
/* now s->internal->rstate == SSL_ST_READ_BODY */
}
/* s->internal->rstate == SSL_ST_READ_BODY, get and decode the data */
n = ssl3_packet_extend(s, SSL3_RT_HEADER_LENGTH + rr->length);
if (n <= 0)
return (n);
if (n != SSL3_RT_HEADER_LENGTH + rr->length)
return (n);
s->internal->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
/* At this point, s->internal->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
* and we have that many bytes in s->internal->packet
*/
rr->input = &(s->internal->packet[SSL3_RT_HEADER_LENGTH]);
/* ok, we can now read from 's->internal->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) {
al = SSL_AD_RECORD_OVERFLOW;
SSLerror(s, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
goto f_err;
}
/* decrypt in place in 'rr->input' */
rr->data = rr->input;
/* 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 = tls1_enc(s, 0)) == 0) {
al = SSL_AD_BAD_RECORD_MAC;
SSLerror(s, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
goto f_err;
}
/* 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)) {
/* 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 = rr->length + rr->padding_length;
/* 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 (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 &&
orig_len < mac_size + 1)) {
al = SSL_AD_DECODE_ERROR;
SSLerror(s, 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, orig_len);
rr->length -= mac_size;
} else {
/* In this case there's no padding, so |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 = tls1_mac(s,md,0 /* not send */);
if (i < 0 || mac == NULL ||
timingsafe_memcmp(md, mac, (size_t)mac_size) != 0)
enc_err = -1;
if (rr->length >
SSL3_RT_MAX_COMPRESSED_LENGTH + 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;
SSLerror(s, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
goto f_err;
}
if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) {
al = SSL_AD_RECORD_OVERFLOW;
SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
goto f_err;
}
rr->off = 0;
/*
* So at this point the following is true
*
* ssl->s3->internal->rrec.type is the type of record
* ssl->s3->internal->rrec.length == number of bytes in record
* ssl->s3->internal->rrec.off == offset to first valid byte
* ssl->s3->internal->rrec.data == where to take bytes from, increment
* after use :-).
*/
/* we have pulled in a full packet so zero things */
s->internal->packet_length = 0;
if (rr->length == 0) {
/*
* CBC countermeasures for known IV weaknesses
* can legitimately insert a single empty record,
* so we allow ourselves to read once past a single
* empty record without forcing want_read.
*/
if (s->internal->empty_record_count++ > SSL_MAX_EMPTY_RECORDS) {
SSLerror(s, SSL_R_PEER_BEHAVING_BADLY);
return -1;
}
if (s->internal->empty_record_count > 1) {
ssl_force_want_read(s);
return -1;
}
goto again;
} else {
s->internal->empty_record_count = 0;
}
return (1);
f_err:
ssl3_send_alert(s, SSL3_AL_FATAL, al);
err:
return (ret);
}
/* 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_;
unsigned int tot, n, nw;
int i;
if (len < 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
s->internal->rwstate = SSL_NOTHING;
tot = S3I(s)->wnum;
S3I(s)->wnum = 0;
if (SSL_in_init(s) && !s->internal->in_handshake) {
i = s->internal->handshake_func(s);
if (i < 0)
return (i);
if (i == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return -1;
}
}
if (len < tot)
len = 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);
if (i <= 0) {
S3I(s)->wnum = tot;
return i;
}
if ((i == (int)n) || (type == SSL3_RT_APPLICATION_DATA &&
(s->internal->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) {
/*
* Next chunk of data should get another prepended
* empty fragment in ciphersuites with known-IV
* weakness.
*/
S3I(s)->empty_fragment_done = 0;
return tot + i;
}
n -= i;
tot += i;
}
}
static int
do_ssl3_write(SSL *s, int type, const unsigned char *buf, unsigned int len)
{
SSL3_BUFFER_INTERNAL *wb = &(S3I(s)->wbuf);
SSL_SESSION *sess = s->session;
int need_empty_fragment = 0;
size_t align, out_len;
uint16_t version;
CBB cbb;
int ret;
memset(&cbb, 0, sizeof(cbb));
if (wb->buf == NULL)
if (!ssl3_setup_write_buffer(s))
return -1;
/*
* First check if there is a SSL3_BUFFER_INTERNAL 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, let's send it. */
if (S3I(s)->alert_dispatch) {
if ((ret = s->method->ssl_dispatch_alert(s)) <= 0)
return (ret);
/* If it went, fall through and send more stuff. */
/* We may have released our buffer, if so get it again. */
if (wb->buf == NULL)
if (!ssl3_setup_write_buffer(s))
return -1;
}
if (len == 0)
return 0;
/*
* Some servers hang if initial client hello is larger than 256
* bytes and record version number > TLS 1.0.
*/
version = s->version;
if (S3I(s)->hs.state == SSL3_ST_CW_CLNT_HELLO_B && !s->internal->renegotiate &&
TLS1_get_version(s) > TLS1_VERSION)
version = TLS1_VERSION;
/*
* Countermeasure against known-IV weakness in CBC ciphersuites
* (see http://www.openssl.org/~bodo/tls-cbc.txt). Note that this
* is unnecessary for AEAD.
*/
if (sess != NULL && s->internal->enc_write_ctx != NULL &&
EVP_MD_CTX_md(s->internal->write_hash) != NULL) {
if (S3I(s)->need_empty_fragments &&
!S3I(s)->empty_fragment_done &&
type == SSL3_RT_APPLICATION_DATA)
need_empty_fragment = 1;
}
/*
* An extra fragment would be a couple of cipher blocks, which would
* be a multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real
* payload, then we can just simply pretend we have two headers.
*/
align = (size_t)wb->buf + SSL3_RT_HEADER_LENGTH;
if (need_empty_fragment)
align += SSL3_RT_HEADER_LENGTH;
align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
wb->offset = align;
if (!CBB_init_fixed(&cbb, wb->buf + align, wb->len - align))
goto err;
tls12_record_layer_set_version(s->internal->rl, version);
if (need_empty_fragment) {
if (!tls12_record_layer_seal_record(s->internal->rl, type,
buf, 0, &cbb))
goto err;
S3I(s)->empty_fragment_done = 1;
}
if (!tls12_record_layer_seal_record(s->internal->rl, type, buf, len, &cbb))
goto err;
if (!CBB_finish(&cbb, NULL, &out_len))
goto err;
wb->left = out_len;
/*
* Memorize arguments so that ssl3_write_pending can detect
* bad write retries later.
*/
S3I(s)->wpend_tot = len;
S3I(s)->wpend_buf = buf;
S3I(s)->wpend_type = type;
S3I(s)->wpend_ret = len;
/* We now just need to write the buffer. */
return ssl3_write_pending(s, type, buf, len);
err:
CBB_cleanup(&cbb);
return -1;
}
/* if S3I(s)->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_INTERNAL *wb = &(S3I(s)->wbuf);
/* XXXX */
if ((S3I(s)->wpend_tot > (int)len) || ((S3I(s)->wpend_buf != buf) &&
!(s->internal->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) ||
(S3I(s)->wpend_type != type)) {
SSLerror(s, SSL_R_BAD_WRITE_RETRY);
return (-1);
}
for (;;) {
errno = 0;
if (s->wbio != NULL) {
s->internal->rwstate = SSL_WRITING;
i = BIO_write(s->wbio, (char *)&(wb->buf[wb->offset]),
(unsigned int)wb->left);
} else {
SSLerror(s, SSL_R_BIO_NOT_SET);
i = -1;
}
if (i == wb->left) {
wb->left = 0;
wb->offset += i;
if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS &&
!SSL_IS_DTLS(s))
ssl3_release_write_buffer(s);
s->internal->rwstate = SSL_NOTHING;
return (S3I(s)->wpend_ret);
} else if (i <= 0) {
/*
* For DTLS, just drop it. That's kind of the
* whole point in using a datagram service.
*/
if (SSL_IS_DTLS(s))
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)
{
void (*cb)(const SSL *ssl, int type2, int val) = NULL;
int al, i, j, ret, rrcount = 0;
unsigned int n;
SSL3_RECORD_INTERNAL *rr;
if (S3I(s)->rbuf.buf == NULL) /* Not initialized yet */
if (!ssl3_setup_read_buffer(s))
return (-1);
if (len < 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if ((type && type != SSL3_RT_APPLICATION_DATA &&
type != SSL3_RT_HANDSHAKE) ||
(peek && (type != SSL3_RT_APPLICATION_DATA))) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return -1;
}
if ((type == SSL3_RT_HANDSHAKE) &&
(S3I(s)->handshake_fragment_len > 0)) {
/* (partially) satisfy request from storage */
unsigned char *src = S3I(s)->handshake_fragment;
unsigned char *dst = buf;
unsigned int k;
/* peek == 0 */
n = 0;
while ((len > 0) && (S3I(s)->handshake_fragment_len > 0)) {
*dst++ = *src++;
len--;
S3I(s)->handshake_fragment_len--;
n++;
}
/* move any remaining fragment bytes: */
for (k = 0; k < S3I(s)->handshake_fragment_len; k++)
S3I(s)->handshake_fragment[k] = *src++;
return n;
}
/*
* Now S3I(s)->handshake_fragment_len == 0 if
* type == SSL3_RT_HANDSHAKE.
*/
if (!s->internal->in_handshake && SSL_in_init(s)) {
/* type == SSL3_RT_APPLICATION_DATA */
i = s->internal->handshake_func(s);
if (i < 0)
return (i);
if (i == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return (-1);
}
}
start:
/*
* Do not process more than three consecutive records, otherwise the
* peer can cause us to loop indefinitely. Instead, return with an
* SSL_ERROR_WANT_READ so the caller can choose when to handle further
* processing. In the future, the total number of non-handshake and
* non-application data records per connection should probably also be
* limited...
*/
if (rrcount++ >= 3) {
ssl_force_want_read(s);
return -1;
}
s->internal->rwstate = SSL_NOTHING;
/*
* S3I(s)->rrec.type - is the type of record
* S3I(s)->rrec.data, - data
* S3I(s)->rrec.off, - offset into 'data' for next read
* S3I(s)->rrec.length, - number of bytes.
*/
rr = &(S3I(s)->rrec);
/* get new packet if necessary */
if ((rr->length == 0) || (s->internal->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 (S3I(s)->change_cipher_spec /* set when we receive ChangeCipherSpec,
* reset by ssl3_get_finished */
&& (rr->type != SSL3_RT_HANDSHAKE)) {
al = SSL_AD_UNEXPECTED_MESSAGE;
SSLerror(s, 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->internal->shutdown & SSL_RECEIVED_SHUTDOWN) {
rr->length = 0;
s->internal->rwstate = SSL_NOTHING;
return (0);
}
/* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
if (type == rr->type) {
/* 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;
SSLerror(s, 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) {
memset(&(rr->data[rr->off]), 0, n);
rr->length -= n;
rr->off += n;
if (rr->length == 0) {
s->internal->rstate = SSL_ST_READ_HEADER;
rr->off = 0;
if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS &&
S3I(s)->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 S3I(s)->handshake_fragment;
dest = S3I(s)->handshake_fragment;
dest_len = &S3I(s)->handshake_fragment_len;
} else if (rr->type == SSL3_RT_ALERT) {
dest_maxlen = sizeof S3I(s)->alert_fragment;
dest = S3I(s)->alert_fragment;
dest_len = &S3I(s)->alert_fragment_len;
}
if (dest_maxlen > 0) {
/* available space in 'dest' */
n = dest_maxlen - *dest_len;
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 */
}
}
/* S3I(s)->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
* S3I(s)->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) && (S3I(s)->handshake_fragment_len >= 4) &&
(S3I(s)->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
(s->session != NULL) && (s->session->cipher != NULL)) {
S3I(s)->handshake_fragment_len = 0;
if ((S3I(s)->handshake_fragment[1] != 0) ||
(S3I(s)->handshake_fragment[2] != 0) ||
(S3I(s)->handshake_fragment[3] != 0)) {
al = SSL_AD_DECODE_ERROR;
SSLerror(s, SSL_R_BAD_HELLO_REQUEST);
goto f_err;
}
if (s->internal->msg_callback)
s->internal->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
S3I(s)->handshake_fragment, 4, s,
s->internal->msg_callback_arg);
if (SSL_is_init_finished(s) &&
!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
!S3I(s)->renegotiate) {
ssl3_renegotiate(s);
if (ssl3_renegotiate_check(s)) {
i = s->internal->handshake_func(s);
if (i < 0)
return (i);
if (i == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return (-1);
}
if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) {
if (S3I(s)->rbuf.left == 0) {
/* no read-ahead left? */
/* 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 */
ssl_force_want_read(s);
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;
}
/* Disallow client initiated renegotiation if configured. */
if (s->server && SSL_is_init_finished(s) &&
S3I(s)->handshake_fragment_len >= 4 &&
S3I(s)->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO &&
(s->internal->options & SSL_OP_NO_CLIENT_RENEGOTIATION)) {
al = SSL_AD_NO_RENEGOTIATION;
goto f_err;
}
/* 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) &&
!S3I(s)->send_connection_binding &&
(S3I(s)->handshake_fragment_len >= 4) &&
(S3I(s)->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
(s->session != NULL) && (s->session->cipher != NULL)) {
/*S3I(s)->handshake_fragment_len = 0;*/
rr->length = 0;
ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
goto start;
}
if (S3I(s)->alert_fragment_len >= 2) {
int alert_level = S3I(s)->alert_fragment[0];
int alert_descr = S3I(s)->alert_fragment[1];
S3I(s)->alert_fragment_len = 0;
if (s->internal->msg_callback)
s->internal->msg_callback(0, s->version, SSL3_RT_ALERT,
S3I(s)->alert_fragment, 2, s, s->internal->msg_callback_arg);
if (s->internal->info_callback != NULL)
cb = s->internal->info_callback;
else if (s->ctx->internal->info_callback != NULL)
cb = s->ctx->internal->info_callback;
if (cb != NULL) {
j = (alert_level << 8) | alert_descr;
cb(s, SSL_CB_READ_ALERT, j);
}
if (alert_level == SSL3_AL_WARNING) {
S3I(s)->warn_alert = alert_descr;
if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
s->internal->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;
SSLerror(s, SSL_R_NO_RENEGOTIATION);
goto f_err;
}
} else if (alert_level == SSL3_AL_FATAL) {
s->internal->rwstate = SSL_NOTHING;
S3I(s)->fatal_alert = alert_descr;
SSLerror(s, SSL_AD_REASON_OFFSET + alert_descr);
ERR_asprintf_error_data("SSL alert number %d",
alert_descr);
s->internal->shutdown |= SSL_RECEIVED_SHUTDOWN;
SSL_CTX_remove_session(s->ctx, s->session);
return (0);
} else {
al = SSL_AD_ILLEGAL_PARAMETER;
SSLerror(s, SSL_R_UNKNOWN_ALERT_TYPE);
goto f_err;
}
goto start;
}
if (s->internal->shutdown & SSL_SENT_SHUTDOWN) {
/* but we have not received a shutdown */
s->internal->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;
SSLerror(s, SSL_R_BAD_CHANGE_CIPHER_SPEC);
goto f_err;
}
/* Check we have a cipher to change to */
if (S3I(s)->hs.new_cipher == NULL) {
al = SSL_AD_UNEXPECTED_MESSAGE;
SSLerror(s, SSL_R_CCS_RECEIVED_EARLY);
goto f_err;
}
/* Check that we should be receiving a Change Cipher Spec. */
if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) {
al = SSL_AD_UNEXPECTED_MESSAGE;
SSLerror(s, SSL_R_CCS_RECEIVED_EARLY);
goto f_err;
}
s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
rr->length = 0;
if (s->internal->msg_callback) {
s->internal->msg_callback(0, s->version,
SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s,
s->internal->msg_callback_arg);
}
S3I(s)->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 ((S3I(s)->handshake_fragment_len >= 4) && !s->internal->in_handshake) {
if (((S3I(s)->hs.state&SSL_ST_MASK) == SSL_ST_OK) &&
!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
S3I(s)->hs.state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
s->internal->renegotiate = 1;
s->internal->new_session = 1;
}
i = s->internal->handshake_func(s);
if (i < 0)
return (i);
if (i == 0) {
SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE);
return (-1);
}
if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) {
if (S3I(s)->rbuf.left == 0) { /* no read-ahead left? */
/* 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 */
ssl_force_want_read(s);
return (-1);
}
}
goto start;
}
switch (rr->type) {
default:
/*
* 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;
}
al = SSL_AD_UNEXPECTED_MESSAGE;
SSLerror(s, 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->internal->in_handshake is set, but that
* should not happen when type != rr->type */
al = SSL_AD_UNEXPECTED_MESSAGE;
SSLerror(s, 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 (S3I(s)->in_read_app_data &&
(S3I(s)->total_renegotiations != 0) &&
(((S3I(s)->hs.state & SSL_ST_CONNECT) &&
(S3I(s)->hs.state >= SSL3_ST_CW_CLNT_HELLO_A) &&
(S3I(s)->hs.state <= SSL3_ST_CR_SRVR_HELLO_A)) ||
((S3I(s)->hs.state & SSL_ST_ACCEPT) &&
(S3I(s)->hs.state <= SSL3_ST_SW_HELLO_REQ_A) &&
(S3I(s)->hs.state >= SSL3_ST_SR_CLNT_HELLO_A)))) {
S3I(s)->in_read_app_data = 2;
return (-1);
} else {
al = SSL_AD_UNEXPECTED_MESSAGE;
SSLerror(s, 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 (S3I(s)->hs.state & SSL_ST_ACCEPT)
i = SSL3_CHANGE_CIPHER_SERVER_READ;
else
i = SSL3_CHANGE_CIPHER_CLIENT_READ;
if (S3I(s)->hs.key_block == NULL) {
if (s->session == NULL || s->session->master_key_length == 0) {
/* might happen if dtls1_read_bytes() calls this */
SSLerror(s, SSL_R_CCS_RECEIVED_EARLY);
return (0);
}
s->session->cipher = S3I(s)->hs.new_cipher;
if (!tls1_setup_key_block(s))
return (0);
}
if (!tls1_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 (S3I(s)->hs.state & SSL_ST_CONNECT) {
sender = TLS_MD_SERVER_FINISH_CONST;
slen = TLS_MD_SERVER_FINISH_CONST_SIZE;
} else {
sender = TLS_MD_CLIENT_FINISH_CONST;
slen = TLS_MD_CLIENT_FINISH_CONST_SIZE;
}
i = tls1_final_finish_mac(s, sender, slen,
S3I(s)->tmp.peer_finish_md);
if (i == 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return 0;
}
S3I(s)->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 = tls1_alert_code(desc);
if (desc < 0)
return -1;
/* If a fatal one, remove from cache */
if ((level == 2) && (s->session != NULL))
SSL_CTX_remove_session(s->ctx, s->session);
S3I(s)->alert_dispatch = 1;
S3I(s)->send_alert[0] = level;
S3I(s)->send_alert[1] = desc;
if (S3I(s)->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;
S3I(s)->alert_dispatch = 0;
i = do_ssl3_write(s, SSL3_RT_ALERT, &S3I(s)->send_alert[0], 2);
if (i <= 0) {
S3I(s)->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 (S3I(s)->send_alert[0] == SSL3_AL_FATAL)
(void)BIO_flush(s->wbio);
if (s->internal->msg_callback)
s->internal->msg_callback(1, s->version, SSL3_RT_ALERT,
S3I(s)->send_alert, 2, s, s->internal->msg_callback_arg);
if (s->internal->info_callback != NULL)
cb = s->internal->info_callback;
else if (s->ctx->internal->info_callback != NULL)
cb = s->ctx->internal->info_callback;
if (cb != NULL) {
j = (S3I(s)->send_alert[0]<<8)|S3I(s)->send_alert[1];
cb(s, SSL_CB_WRITE_ALERT, j);
}
}
return (i);
}
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