|
- /* 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 <assert.h>
- #include <limits.h>
- #include <stdio.h>
- #include <string.h>
-
- #include <openssl/buf.h>
- #include <openssl/err.h>
- #include <openssl/evp.h>
- #include <openssl/mem.h>
- #include <openssl/rand.h>
-
- #include "internal.h"
-
-
- static int do_ssl3_write(SSL *s, int type, const uint8_t *buf, unsigned int len,
- char fragment);
- static int ssl3_get_record(SSL *s);
-
- int ssl3_read_n(SSL *s, int n, int extend) {
- /* If |extend| is 0, obtain new n-byte packet;
- * if |extend| is 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 DTLS and |extend| is 0, additional
- * bytes will be read into |rbuf|, up to the size of the buffer.)
- *
- * TODO(davidben): |dtls1_get_record| and |ssl3_get_record| have very
- * different needs. Separate the two record layers. In DTLS, |BIO_read| is
- * called at most once, and only when |extend| is 0. In TLS, the buffer never
- * contains more than one record. */
- int i, len, left;
- uintptr_t align = 0;
- uint8_t *pkt;
- SSL3_BUFFER *rb;
-
- if (n <= 0) {
- return n;
- }
-
- rb = &s->s3->rbuf;
- if (rb->buf == NULL && !ssl3_setup_read_buffer(s)) {
- return -1;
- }
-
- left = rb->left;
-
- align = (uintptr_t)rb->buf + SSL3_RT_HEADER_LENGTH;
- align = (0 - 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->packet = rb->buf + rb->offset;
- s->packet_length = 0;
- /* ... now we can act as if 'extend' was set */
- }
-
- /* In DTLS, if there is leftover data from the previous packet or |extend| is
- * true, clamp to the previous read. DTLS records may not span packet
- * boundaries. */
- if (SSL_IS_DTLS(s) && n > left && (left > 0 || extend)) {
- 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)) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return -1;
- }
-
- int max = n;
- if (SSL_IS_DTLS(s) && !extend) {
- 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). */
- ERR_clear_system_error();
- if (s->rbio != NULL) {
- s->rwstate = SSL_READING;
- i = BIO_read(s->rbio, pkt + len + left, max - left);
- } else {
- OPENSSL_PUT_ERROR(SSL, SSL_R_READ_BIO_NOT_SET);
- i = -1;
- }
-
- if (i <= 0) {
- rb->left = left;
- 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) && 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;
- }
-
- /* kMaxEmptyRecords is the number of consecutive, empty records that will be
- * processed. 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. */
- static const uint8_t kMaxEmptyRecords = 32;
-
- /* kMaxWarningAlerts is the number of consecutive warning alerts that will be
- * processed. */
- static const uint8_t kMaxWarningAlerts = 4;
-
- /* 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) {
- uint8_t ssl_major, ssl_minor;
- int al, n, i, ret = -1;
- SSL3_RECORD *rr = &s->s3->rrec;
- uint8_t *p;
- uint16_t version;
- size_t extra;
-
- 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, 0);
- if (n <= 0) {
- return n; /* error or non-blocking */
- }
- s->rstate = SSL_ST_READ_BODY;
-
- /* Some bytes were read, so the read buffer must be existant and
- * |s->s3->init_extra| is defined. */
- assert(s->s3->rbuf.buf != NULL);
- extra = s->s3->init_extra ? SSL3_RT_MAX_EXTRA : 0;
-
- 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 = (((uint16_t)ssl_major) << 8) | ssl_minor;
- n2s(p, rr->length);
-
- if (s->s3->have_version && version != s->version) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER);
- al = SSL_AD_PROTOCOL_VERSION;
- goto f_err;
- }
-
- if ((version >> 8) != SSL3_VERSION_MAJOR) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER);
- goto err;
- }
-
- if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
- al = SSL_AD_RECORD_OVERFLOW;
- OPENSSL_PUT_ERROR(SSL, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
- goto f_err;
- }
-
- /* now s->rstate == SSL_ST_READ_BODY */
- } else {
- /* |packet_length| is non-zero and |s->rstate| is |SSL_ST_READ_BODY|. The
- * read buffer must be existant and |s->s3->init_extra| is defined. */
- assert(s->s3->rbuf.buf != NULL);
- extra = s->s3->init_extra ? SSL3_RT_MAX_EXTRA : 0;
- }
-
- /* 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, 1);
- if (n <= 0) {
- /* Error or non-blocking IO. Now |n| == |rr->length|, and
- * |s->packet_length| == |SSL3_RT_HEADER_LENGTH| + |rr->length|. */
- return n;
- }
- }
-
- s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
-
- /* |rr->data| points to |rr->length| bytes of ciphertext in |s->packet|. */
- rr->data = &s->packet[SSL3_RT_HEADER_LENGTH];
-
- /* Decrypt the packet in-place.
- *
- * TODO(davidben): This assumes |s->version| is the same as the record-layer
- * version which isn't always true, but it only differs with the NULL cipher
- * which ignores the parameter. */
- size_t plaintext_len;
- if (!SSL_AEAD_CTX_open(s->aead_read_ctx, rr->data, &plaintext_len, rr->length,
- rr->type, s->version, s->s3->read_sequence, rr->data,
- rr->length)) {
- al = SSL_AD_BAD_RECORD_MAC;
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
- goto f_err;
- }
- if (!ssl3_record_sequence_update(s->s3->read_sequence, 8)) {
- goto err;
- }
- if (plaintext_len > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
- al = SSL_AD_RECORD_OVERFLOW;
- OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG);
- goto f_err;
- }
- assert(plaintext_len <= (1u << 16));
- rr->length = plaintext_len;
-
- rr->off = 0;
- /* So at this point the following is true:
- * ssl->s3->rrec.type is the type of record;
- * ssl->s3->rrec.length is the number of bytes in the record;
- * ssl->s3->rrec.off is the offset to first valid byte;
- * ssl->s3->rrec.data the first byte of the record body. */
-
- /* we have pulled in a full packet so zero things */
- s->packet_length = 0;
-
- /* just read a 0 length packet */
- if (rr->length == 0) {
- s->s3->empty_record_count++;
- if (s->s3->empty_record_count > kMaxEmptyRecords) {
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_EMPTY_FRAGMENTS);
- goto f_err;
- }
- goto again;
- }
- s->s3->empty_record_count = 0;
-
- return 1;
-
- f_err:
- ssl3_send_alert(s, SSL3_AL_FATAL, al);
- err:
- return ret;
- }
-
- int ssl3_write_app_data(SSL *ssl, const void *buf, int len) {
- return ssl3_write_bytes(ssl, SSL3_RT_APPLICATION_DATA, buf, len);
- }
-
- /* 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 uint8_t *buf = buf_;
- unsigned int tot, n, nw;
- int i;
-
- s->rwstate = SSL_NOTHING;
- assert(s->s3->wnum <= INT_MAX);
- tot = s->s3->wnum;
- s->s3->wnum = 0;
-
- if (!s->in_handshake && SSL_in_init(s) && !SSL_in_false_start(s)) {
- i = s->handshake_func(s);
- if (i < 0) {
- return i;
- }
- if (i == 0) {
- OPENSSL_PUT_ERROR(SSL, 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 < 0 || (size_t)len < tot) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_LENGTH);
- return -1;
- }
-
- int record_split_done = 0;
- n = (len - tot);
- for (;;) {
- /* max contains the maximum number of bytes that we can put into a
- * record. */
- unsigned max = s->max_send_fragment;
- /* fragment is true if do_ssl3_write should send the first byte in its own
- * record in order to randomise a CBC IV. */
- int fragment = 0;
- if (!record_split_done && s->s3->need_record_splitting &&
- type == SSL3_RT_APPLICATION_DATA) {
- /* Only the the first record per write call needs to be split. The
- * remaining plaintext was determined before the IV was randomized. */
- fragment = 1;
- record_split_done = 1;
- }
- if (n > max) {
- nw = max;
- } else {
- nw = n;
- }
-
- i = do_ssl3_write(s, type, &buf[tot], nw, fragment);
- 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))) {
- return tot + i;
- }
-
- n -= i;
- tot += i;
- }
- }
-
- /* ssl3_seal_record seals a new record of type |type| and plaintext |in| and
- * writes it to |out|. At most |max_out| bytes will be written. It returns one
- * on success and zero on error. On success, it updates the write sequence
- * number. */
- static int ssl3_seal_record(SSL *s, uint8_t *out, size_t *out_len,
- size_t max_out, uint8_t type, const uint8_t *in,
- size_t in_len) {
- if (max_out < SSL3_RT_HEADER_LENGTH) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL);
- return 0;
- }
-
- out[0] = type;
-
- /* Some servers hang if initial ClientHello is larger than 256 bytes and
- * record version number > TLS 1.0. */
- uint16_t wire_version = s->version;
- if (!s->s3->have_version && s->version > SSL3_VERSION) {
- wire_version = TLS1_VERSION;
- }
- out[1] = wire_version >> 8;
- out[2] = wire_version & 0xff;
-
- size_t ciphertext_len;
- if (!SSL_AEAD_CTX_seal(s->aead_write_ctx, out + SSL3_RT_HEADER_LENGTH,
- &ciphertext_len, max_out - SSL3_RT_HEADER_LENGTH,
- type, wire_version, s->s3->write_sequence, in,
- in_len) ||
- !ssl3_record_sequence_update(s->s3->write_sequence, 8)) {
- return 0;
- }
-
- if (ciphertext_len >= 1 << 16) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
- return 0;
- }
- out[3] = ciphertext_len >> 8;
- out[4] = ciphertext_len & 0xff;
-
- *out_len = SSL3_RT_HEADER_LENGTH + ciphertext_len;
-
- if (s->msg_callback) {
- s->msg_callback(1 /* write */, 0, SSL3_RT_HEADER, out, SSL3_RT_HEADER_LENGTH,
- s, s->msg_callback_arg);
- }
-
- return 1;
- }
-
- /* do_ssl3_write writes an SSL record of the given type. If |fragment| is 1
- * then it splits the record into a one byte record and a record with the rest
- * of the data in order to randomise a CBC IV. */
- static int do_ssl3_write(SSL *s, int type, const uint8_t *buf, unsigned int len,
- char fragment) {
- SSL3_BUFFER *wb = &s->s3->wbuf;
-
- /* 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) {
- int ret = s->method->ssl_dispatch_alert(s);
- if (ret <= 0) {
- return ret;
- }
- /* if it went, fall through and send more stuff */
- }
-
- if (wb->buf == NULL && !ssl3_setup_write_buffer(s)) {
- return -1;
- }
-
- if (len == 0) {
- return 0;
- }
- if (len == 1) {
- /* No sense in fragmenting a one-byte record. */
- fragment = 0;
- }
-
- /* Align the output so the ciphertext is aligned to |SSL3_ALIGN_PAYLOAD|. */
- uintptr_t align;
- if (fragment) {
- /* Only CBC-mode ciphers require fragmenting. CBC-mode ciphertext is a
- * multiple of the block size which we may assume is aligned. Thus we only
- * need to account for a second copy of the record header. */
- align = (uintptr_t)wb->buf + 2 * SSL3_RT_HEADER_LENGTH;
- } else {
- align = (uintptr_t)wb->buf + SSL3_RT_HEADER_LENGTH;
- }
- align = (0 - align) & (SSL3_ALIGN_PAYLOAD - 1);
- uint8_t *out = wb->buf + align;
- wb->offset = align;
- size_t max_out = wb->len - wb->offset;
-
- const uint8_t *orig_buf = buf;
- unsigned int orig_len = len;
- size_t fragment_len = 0;
- if (fragment) {
- /* Write the first byte in its own record as a countermeasure against
- * known-IV weaknesses in CBC ciphersuites. (See
- * http://www.openssl.org/~bodo/tls-cbc.txt.) */
- if (!ssl3_seal_record(s, out, &fragment_len, max_out, type, buf, 1)) {
- return -1;
- }
- out += fragment_len;
- max_out -= fragment_len;
- buf++;
- len--;
- }
-
- assert((((uintptr_t)out + SSL3_RT_HEADER_LENGTH) & (SSL3_ALIGN_PAYLOAD - 1))
- == 0);
- size_t ciphertext_len;
- if (!ssl3_seal_record(s, out, &ciphertext_len, max_out, type, buf, len)) {
- return -1;
- }
- ciphertext_len += fragment_len;
-
- /* now let's set up wb */
- wb->left = ciphertext_len;
-
- /* memorize arguments so that ssl3_write_pending can detect bad write retries
- * later */
- s->s3->wpend_tot = orig_len;
- s->s3->wpend_buf = orig_buf;
- s->s3->wpend_type = type;
- s->s3->wpend_ret = orig_len;
-
- /* we now just need to write the buffer */
- return ssl3_write_pending(s, type, orig_buf, orig_len);
- }
-
- /* if s->s3->wbuf.left != 0, we need to call this */
- int ssl3_write_pending(SSL *s, int type, const uint8_t *buf, unsigned int len) {
- int i;
- SSL3_BUFFER *wb = &(s->s3->wbuf);
-
- 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) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_WRITE_RETRY);
- return -1;
- }
-
- for (;;) {
- ERR_clear_system_error();
- if (s->wbio != NULL) {
- s->rwstate = SSL_WRITING;
- i = BIO_write(s->wbio, (char *)&(wb->buf[wb->offset]),
- (unsigned int)wb->left);
- } else {
- OPENSSL_PUT_ERROR(SSL, SSL_R_BIO_NOT_SET);
- i = -1;
- }
- if (i == wb->left) {
- wb->left = 0;
- wb->offset += i;
- ssl3_release_write_buffer(s);
- s->rwstate = SSL_NOTHING;
- return s->s3->wpend_ret;
- } else if (i <= 0) {
- if (SSL_IS_DTLS(s)) {
- /* For DTLS, just drop it. That's kind of the whole point in
- * using a datagram service */
- wb->left = 0;
- }
- return i;
- }
- /* TODO(davidben): This codepath is used in DTLS, but the write
- * payload may not split across packets. */
- wb->offset += i;
- wb->left -= i;
- }
- }
-
- /* ssl3_expect_change_cipher_spec informs the record layer that a
- * ChangeCipherSpec record is required at this point. If a Handshake record is
- * received before ChangeCipherSpec, the connection will fail. Moreover, if
- * there are unprocessed handshake bytes, the handshake will also fail and the
- * function returns zero. Otherwise, the function returns one. */
- int ssl3_expect_change_cipher_spec(SSL *s) {
- if (s->s3->handshake_fragment_len > 0 || s->s3->tmp.reuse_message) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNPROCESSED_HANDSHAKE_DATA);
- return 0;
- }
-
- s->s3->flags |= SSL3_FLAGS_EXPECT_CCS;
- return 1;
- }
-
- int ssl3_read_app_data(SSL *ssl, uint8_t *buf, int len, int peek) {
- return ssl3_read_bytes(ssl, SSL3_RT_APPLICATION_DATA, buf, len, peek);
- }
-
- void ssl3_read_close_notify(SSL *ssl) {
- ssl3_read_bytes(ssl, 0, NULL, 0, 0);
- }
-
- /* 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, uint8_t *buf, int len, int peek) {
- int al, i, ret;
- unsigned int n;
- SSL3_RECORD *rr;
- void (*cb)(const SSL *ssl, int type2, int val) = NULL;
-
- if ((type && type != SSL3_RT_APPLICATION_DATA && type != SSL3_RT_HANDSHAKE) ||
- (peek && type != SSL3_RT_APPLICATION_DATA)) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return -1;
- }
-
- if (type == SSL3_RT_HANDSHAKE && s->s3->handshake_fragment_len > 0) {
- /* (partially) satisfy request from storage */
- uint8_t *src = s->s3->handshake_fragment;
- uint8_t *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. */
-
- /* This may require multiple iterations. False Start will cause
- * |s->handshake_func| to signal success one step early, but the handshake
- * must be completely finished before other modes are accepted.
- *
- * TODO(davidben): Move this check up to a higher level. */
- while (!s->in_handshake && SSL_in_init(s)) {
- assert(type == SSL3_RT_APPLICATION_DATA);
- i = s->handshake_func(s);
- if (i < 0) {
- return i;
- }
- if (i == 0) {
- OPENSSL_PUT_ERROR(SSL, 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 */
-
- /* |change_cipher_spec is set when we receive a ChangeCipherSpec and reset by
- * ssl3_get_finished. */
- if (s->s3->change_cipher_spec && rr->type != SSL3_RT_HANDSHAKE &&
- rr->type != SSL3_RT_ALERT) {
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
- goto f_err;
- }
-
- /* If we are expecting a ChangeCipherSpec, it is illegal to receive a
- * Handshake record. */
- if (rr->type == SSL3_RT_HANDSHAKE && (s->s3->flags & SSL3_FLAGS_EXPECT_CCS)) {
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_HANDSHAKE_RECORD_BEFORE_CCS);
- 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) {
- s->s3->warning_alert_count = 0;
-
- /* 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->aead_read_ctx == NULL) {
- /* TODO(davidben): Is this check redundant with the handshake_func
- * check? */
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, 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->s3->rbuf.left == 0) {
- ssl3_release_read_buffer(s);
- }
- }
- }
-
- return n;
- }
-
- /* Process unexpected records. */
-
- if (rr->type == SSL3_RT_HANDSHAKE) {
- /* If peer renegotiations are disabled, all out-of-order handshake records
- * are fatal. Renegotiations as a server are never supported. */
- if (!s->accept_peer_renegotiations || s->server) {
- al = SSL_AD_NO_RENEGOTIATION;
- OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION);
- goto f_err;
- }
-
- /* HelloRequests may be fragmented across multiple records. */
- const size_t size = sizeof(s->s3->handshake_fragment);
- const size_t avail = size - s->s3->handshake_fragment_len;
- const size_t todo = (rr->length < avail) ? rr->length : avail;
- memcpy(s->s3->handshake_fragment + s->s3->handshake_fragment_len,
- &rr->data[rr->off], todo);
- rr->off += todo;
- rr->length -= todo;
- s->s3->handshake_fragment_len += todo;
- if (s->s3->handshake_fragment_len < size) {
- goto start; /* fragment was too small */
- }
-
- /* Parse out and consume a HelloRequest. */
- if (s->s3->handshake_fragment[0] != SSL3_MT_HELLO_REQUEST ||
- s->s3->handshake_fragment[1] != 0 ||
- s->s3->handshake_fragment[2] != 0 ||
- s->s3->handshake_fragment[3] != 0) {
- al = SSL_AD_DECODE_ERROR;
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_HELLO_REQUEST);
- goto f_err;
- }
- s->s3->handshake_fragment_len = 0;
-
- 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->initial_handshake_complete) {
- /* This cannot happen. If a handshake is in progress, |type| must be
- * |SSL3_RT_HANDSHAKE|. */
- assert(0);
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- goto err;
- }
-
- /* Renegotiation is only supported at quiescent points in the application
- * protocol, namely in HTTPS, just before reading the HTTP response. Require
- * the record-layer be idle and avoid complexities of sending a handshake
- * record while an application_data record is being written. */
- if (s->s3->wbuf.left != 0 || s->s3->rbuf.left != 0) {
- al = SSL_AD_NO_RENEGOTIATION;
- OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION);
- goto f_err;
- }
-
- /* Begin a new handshake. */
- s->state = SSL_ST_CONNECT;
- i = s->handshake_func(s);
- if (i < 0) {
- return i;
- }
- if (i == 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_SSL_HANDSHAKE_FAILURE);
- return -1;
- }
-
- /* The handshake completed synchronously. Continue reading records. */
- goto start;
- }
-
- /* If an alert record, process one alert out of the record. Note that we allow
- * a single record to contain multiple alerts. */
- if (rr->type == SSL3_RT_ALERT) {
- /* Alerts may not be fragmented. */
- if (rr->length < 2) {
- al = SSL_AD_DECODE_ERROR;
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_ALERT);
- goto f_err;
- }
-
- if (s->msg_callback) {
- s->msg_callback(0, s->version, SSL3_RT_ALERT, &rr->data[rr->off], 2, s,
- s->msg_callback_arg);
- }
- const uint8_t alert_level = rr->data[rr->off++];
- const uint8_t alert_descr = rr->data[rr->off++];
- rr->length -= 2;
-
- if (s->info_callback != NULL) {
- cb = s->info_callback;
- } else if (s->ctx->info_callback != NULL) {
- cb = s->ctx->info_callback;
- }
-
- if (cb != NULL) {
- uint16_t alert = (alert_level << 8) | alert_descr;
- cb(s, SSL_CB_READ_ALERT, alert);
- }
-
- if (alert_level == SSL3_AL_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;
- OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION);
- goto f_err;
- }
-
- s->s3->warning_alert_count++;
- if (s->s3->warning_alert_count > kMaxWarningAlerts) {
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_WARNING_ALERTS);
- goto f_err;
- }
- } else if (alert_level == SSL3_AL_FATAL) {
- char tmp[16];
-
- s->rwstate = SSL_NOTHING;
- s->s3->fatal_alert = alert_descr;
- OPENSSL_PUT_ERROR(SSL, 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;
- OPENSSL_PUT_ERROR(SSL, 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;
- OPENSSL_PUT_ERROR(SSL, 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;
- OPENSSL_PUT_ERROR(SSL, SSL_R_CCS_RECEIVED_EARLY);
- goto f_err;
- }
-
- if (!(s->s3->flags & SSL3_FLAGS_EXPECT_CCS)) {
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_CCS_RECEIVED_EARLY);
- goto f_err;
- }
-
- s->s3->flags &= ~SSL3_FLAGS_EXPECT_CCS;
-
- 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;
- }
- }
-
- /* We already handled these. */
- assert(rr->type != SSL3_RT_CHANGE_CIPHER_SPEC && rr->type != SSL3_RT_ALERT &&
- rr->type != SSL3_RT_HANDSHAKE);
-
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_RECORD);
-
- f_err:
- ssl3_send_alert(s, SSL3_AL_FATAL, al);
- err:
- return -1;
- }
-
- int ssl3_do_change_cipher_spec(SSL *s) {
- int i;
-
- 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 */
- OPENSSL_PUT_ERROR(SSL, SSL_R_CCS_RECEIVED_EARLY);
- return 0;
- }
-
- s->session->cipher = s->s3->tmp.new_cipher;
- if (!s->enc_method->setup_key_block(s)) {
- return 0;
- }
- }
-
- if (!s->enc_method->change_cipher_state(s, i)) {
- return 0;
- }
-
- return 1;
- }
-
- int ssl3_send_alert(SSL *s, int level, int desc) {
- /* Map tls/ssl alert value to correct one */
- desc = s->enc_method->alert_value(desc);
- if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) {
- /* SSL 3.0 does not have protocol_version alerts */
- desc = SSL_AD_HANDSHAKE_FAILURE;
- }
- 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);
- }
-
- s->s3->alert_dispatch = 1;
- s->s3->send_alert[0] = level;
- s->s3->send_alert[1] = desc;
- if (s->s3->wbuf.left == 0) {
- /* data is 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) {
- 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;
- }
|