1 files changed, 338 insertions, 0 deletions

diff --git a/src/ssl/tls_record.c b/src/ssl/tls_record.c
new file mode 100644
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--- /dev/null
+++ b/src/ssl/tls_record.c
@@ -0,0 +1,338 @@
+/* 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 <openssl/ssl.h>
+
+#include <assert.h>
+
+#include <openssl/bytestring.h>
+#include <openssl/err.h>
+
+#include "internal.h"
+
+
+/* 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 record processing to loop
+ * forever. */
+static const uint8_t kMaxEmptyRecords = 32;
+
+size_t ssl_record_prefix_len(const SSL *ssl) {
+  if (SSL_IS_DTLS(ssl)) {
+    return DTLS1_RT_HEADER_LENGTH +
+           SSL_AEAD_CTX_explicit_nonce_len(ssl->aead_read_ctx);
+  } else {
+    return SSL3_RT_HEADER_LENGTH +
+           SSL_AEAD_CTX_explicit_nonce_len(ssl->aead_read_ctx);
+  }
+}
+
+size_t ssl_seal_prefix_len(const SSL *ssl) {
+  if (SSL_IS_DTLS(ssl)) {
+    return DTLS1_RT_HEADER_LENGTH +
+           SSL_AEAD_CTX_explicit_nonce_len(ssl->aead_write_ctx);
+  } else {
+    size_t ret = SSL3_RT_HEADER_LENGTH +
+                 SSL_AEAD_CTX_explicit_nonce_len(ssl->aead_write_ctx);
+    if (ssl->s3->need_record_splitting) {
+      ret += SSL3_RT_HEADER_LENGTH;
+      ret += ssl_cipher_get_record_split_len(ssl->aead_write_ctx->cipher);
+    }
+    return ret;
+  }
+}
+
+size_t ssl_max_seal_overhead(const SSL *ssl) {
+  if (SSL_IS_DTLS(ssl)) {
+    return DTLS1_RT_HEADER_LENGTH +
+           SSL_AEAD_CTX_max_overhead(ssl->aead_write_ctx);
+  } else {
+    size_t ret = SSL3_RT_HEADER_LENGTH +
+                 SSL_AEAD_CTX_max_overhead(ssl->aead_write_ctx);
+    if (ssl->s3->need_record_splitting) {
+      ret *= 2;
+    }
+    return ret;
+  }
+}
+
+enum ssl_open_record_t tls_open_record(
+    SSL *ssl, uint8_t *out_type, uint8_t *out, size_t *out_len,
+    size_t *out_consumed, uint8_t *out_alert, size_t max_out, const uint8_t *in,
+    size_t in_len) {
+  CBS cbs;
+  CBS_init(&cbs, in, in_len);
+
+  /* Decode the record header. */
+  uint8_t type;
+  uint16_t version, ciphertext_len;
+  if (!CBS_get_u8(&cbs, &type) ||
+      !CBS_get_u16(&cbs, &version) ||
+      !CBS_get_u16(&cbs, &ciphertext_len)) {
+    *out_consumed = SSL3_RT_HEADER_LENGTH;
+    return ssl_open_record_partial;
+  }
+
+  /* Check the version. */
+  if ((ssl->s3->have_version && version != ssl->version) ||
+      (version >> 8) != SSL3_VERSION_MAJOR) {
+    OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER);
+    *out_alert = SSL_AD_PROTOCOL_VERSION;
+    return ssl_open_record_error;
+  }
+
+  /* Check the ciphertext length. */
+  size_t extra = 0;
+  if (ssl->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) {
+    extra = SSL3_RT_MAX_EXTRA;
+  }
+  if (ciphertext_len > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
+    OPENSSL_PUT_ERROR(SSL, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
+    *out_alert = SSL_AD_RECORD_OVERFLOW;
+    return ssl_open_record_error;
+  }
+
+  /* Extract the body. */
+  CBS body;
+  if (!CBS_get_bytes(&cbs, &body, ciphertext_len)) {
+    *out_consumed = SSL3_RT_HEADER_LENGTH + (size_t)ciphertext_len;
+    return ssl_open_record_partial;
+  }
+
+  if (ssl->msg_callback != NULL) {
+    ssl->msg_callback(0 /* read */, 0, SSL3_RT_HEADER, in,
+                      SSL3_RT_HEADER_LENGTH, ssl, ssl->msg_callback_arg);
+  }
+
+  /* Decrypt the body. */
+  size_t plaintext_len;
+  if (!SSL_AEAD_CTX_open(ssl->aead_read_ctx, out, &plaintext_len, max_out,
+                         type, version, ssl->s3->read_sequence, CBS_data(&body),
+                         CBS_len(&body))) {
+    OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
+    *out_alert = SSL_AD_BAD_RECORD_MAC;
+    return ssl_open_record_error;
+  }
+  if (!ssl3_record_sequence_update(ssl->s3->read_sequence, 8)) {
+    *out_alert = SSL_AD_INTERNAL_ERROR;
+    return ssl_open_record_error;
+  }
+
+  /* Check the plaintext length. */
+  if (plaintext_len > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
+    OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG);
+    *out_alert = SSL_AD_RECORD_OVERFLOW;
+    return ssl_open_record_error;
+  }
+
+  /* Limit the number of consecutive empty records. */
+  if (plaintext_len == 0) {
+    ssl->s3->empty_record_count++;
+    if (ssl->s3->empty_record_count > kMaxEmptyRecords) {
+      OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_EMPTY_FRAGMENTS);
+      *out_alert = SSL_AD_UNEXPECTED_MESSAGE;
+      return ssl_open_record_error;
+    }
+    /* Apart from the limit, empty records are returned up to the caller. This
+     * allows the caller to reject records of the wrong type. */
+  } else {
+    ssl->s3->empty_record_count = 0;
+  }
+
+  *out_type = type;
+  *out_len = plaintext_len;
+  *out_consumed = in_len - CBS_len(&cbs);
+  return ssl_open_record_success;
+}
+
+static int do_seal_record(SSL *ssl, 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;
+  }
+  /* Check the record header does not alias any part of the input.
+   * |SSL_AEAD_CTX_seal| will internally enforce other aliasing requirements. */
+  if (in < out + SSL3_RT_HEADER_LENGTH && out < in + in_len) {
+    OPENSSL_PUT_ERROR(SSL, SSL_R_OUTPUT_ALIASES_INPUT);
+    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 = ssl->version;
+  if (!ssl->s3->have_version && ssl->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(ssl->aead_write_ctx, out + SSL3_RT_HEADER_LENGTH,
+                         &ciphertext_len, max_out - SSL3_RT_HEADER_LENGTH,
+                         type, wire_version, ssl->s3->write_sequence, in,
+                         in_len) ||
+      !ssl3_record_sequence_update(ssl->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 (ssl->msg_callback) {
+    ssl->msg_callback(1 /* write */, 0, SSL3_RT_HEADER, out,
+                      SSL3_RT_HEADER_LENGTH, ssl, ssl->msg_callback_arg);
+  }
+
+  return 1;
+}
+
+int tls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
+                    uint8_t type, const uint8_t *in, size_t in_len) {
+  size_t frag_len = 0;
+  if (ssl->s3->need_record_splitting && type == SSL3_RT_APPLICATION_DATA &&
+      in_len > 1) {
+    /* |do_seal_record| will notice if it clobbers |in[0]|, but not if it
+     * aliases the rest of |in|. */
+    if (in + 1 <= out && out < in + in_len) {
+      OPENSSL_PUT_ERROR(SSL, SSL_R_OUTPUT_ALIASES_INPUT);
+      return 0;
+    }
+    /* Ensure |do_seal_record| does not write beyond |in[0]|. */
+    size_t frag_max_out = max_out;
+    if (out <= in + 1 && in + 1 < out + frag_max_out) {
+      frag_max_out = (size_t)(in + 1 - out);
+    }
+    if (!do_seal_record(ssl, out, &frag_len, frag_max_out, type, in, 1)) {
+      return 0;
+    }
+    in++;
+    in_len--;
+    out += frag_len;
+    max_out -= frag_len;
+
+    assert(SSL3_RT_HEADER_LENGTH +
+               ssl_cipher_get_record_split_len(ssl->aead_write_ctx->cipher) ==
+           frag_len);
+  }
+
+  if (!do_seal_record(ssl, out, out_len, max_out, type, in, in_len)) {
+    return 0;
+  }
+  *out_len += frag_len;
+  return 1;
+}