Convert tls_construct_client_hello() to use PACKETW
[openssl.git] / ssl / t1_ext.c
index 115e4345eaae54e7e1ae7380653972f6acacad69..1ccd4c8b15595d5673e1fc3f97a5675cd55cf8cd 100644 (file)
-/* ssl/t1_ext.c */
-/* ====================================================================
- * Copyright (c) 2014 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).
+/*
+ * Copyright 2014-2016 The OpenSSL Project Authors. All Rights Reserved.
  *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
  */
 
 /* Custom extension utility functions */
 
+#include <openssl/ct.h>
 #include "ssl_locl.h"
 
-#ifndef OPENSSL_NO_TLSEXT
-
-/* Find a custom extension from the list */
+/* Find a custom extension from the list. */
+static custom_ext_method *custom_ext_find(const custom_ext_methods *exts,
+                                          unsigned int ext_type)
+{
+    size_t i;
+    custom_ext_method *meth = exts->meths;
+    for (i = 0; i < exts->meths_count; i++, meth++) {
+        if (ext_type == meth->ext_type)
+            return meth;
+    }
+    return NULL;
+}
 
-static custom_ext_method *custom_ext_find(custom_ext_methods *exts,
-                                               unsigned short ext_type)
-       {
-       size_t i;
-       custom_ext_method *meth = exts->meths;
-       for (i = 0; i < exts->meths_count; i++, meth++)
-               {
-               if (ext_type == meth->ext_type)
-                       return meth;
-               }
-       return NULL;
-       }
-/* Initialise custom extensions flags to indicate neither sent nor
- * received.
+/*
+ * Initialise custom extensions flags to indicate neither sent nor received.
  */
 void custom_ext_init(custom_ext_methods *exts)
-       {
-       size_t i;
-       custom_ext_method *meth = exts->meths;
-       for (i = 0; i < exts->meths_count; i++, meth++)
-               meth->ext_flags = 0;
-       }
-
-/* pass received custom extension data to the application for parsing */
+{
+    size_t i;
+    custom_ext_method *meth = exts->meths;
+    for (i = 0; i < exts->meths_count; i++, meth++)
+        meth->ext_flags = 0;
+}
 
+/* Pass received custom extension data to the application for parsing. */
 int custom_ext_parse(SSL *s, int server,
-                       unsigned int ext_type,
-                       const unsigned char *ext_data, 
-                       size_t ext_size,
-                       int *al)
-       {
-       custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
-       custom_ext_method *meth;
-       meth = custom_ext_find(exts, ext_type);
-       /* If not found or no parse function set, return success */
-       /* If not found return success */
-       if (!meth)
-               return 1;
-       if (!server)
-               {
-               /* If it's ServerHello we can't have any extensions not 
-                * sent in ClientHello.
-                */
-               if (!(meth->ext_flags & SSL_EXT_FLAG_SENT))
-                       {
-                       *al = TLS1_AD_UNSUPPORTED_EXTENSION;
-                       return 0;
-                       }
-               }
-       /* If already present it's a duplicate */
-       if (meth->ext_flags & SSL_EXT_FLAG_RECEIVED)
-               {
-               *al = TLS1_AD_DECODE_ERROR;
-               return 0;
-               }
-       meth->ext_flags |= SSL_EXT_FLAG_RECEIVED;
-       if (!meth->parse_cb)
-               return 1;
+                     unsigned int ext_type,
+                     const unsigned char *ext_data, size_t ext_size, int *al)
+{
+    custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
+    custom_ext_method *meth;
+    meth = custom_ext_find(exts, ext_type);
+    /* If not found return success */
+    if (!meth)
+        return 1;
+    if (!server) {
+        /*
+         * If it's ServerHello we can't have any extensions not sent in
+         * ClientHello.
+         */
+        if (!(meth->ext_flags & SSL_EXT_FLAG_SENT)) {
+            *al = TLS1_AD_UNSUPPORTED_EXTENSION;
+            return 0;
+        }
+    }
+    /* If already present it's a duplicate */
+    if (meth->ext_flags & SSL_EXT_FLAG_RECEIVED) {
+        *al = TLS1_AD_DECODE_ERROR;
+        return 0;
+    }
+    meth->ext_flags |= SSL_EXT_FLAG_RECEIVED;
+    /* If no parse function set return success */
+    if (!meth->parse_cb)
+        return 1;
 
-       return meth->parse_cb(s, ext_type, ext_data, ext_size, al, meth->parse_arg);
-       }
+    return meth->parse_cb(s, ext_type, ext_data, ext_size, al, meth->parse_arg);
+}
 
-/* request custom extension data from the application and add to the
- * return buffer
+/*
+ * Request custom extension data from the application and add to the return
+ * buffer. This is the old style function signature prior to PACKETW. This is
+ * here temporarily until the conversion to PACKETW is completed, i.e. it is
+ * used by code that hasn't been converted yet.
+ * TODO - REMOVE THIS FUNCTION
  */
+int custom_ext_add_old(SSL *s, int server,
+                       unsigned char **pret, unsigned char *limit, int *al)
+{
+    custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
+    custom_ext_method *meth;
+    unsigned char *ret = *pret;
+    size_t i;
 
-int custom_ext_add(SSL *s, int server,
-                       unsigned char **pret,
-                       unsigned char *limit,
-                       int *al)
-       {
-       custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
-       custom_ext_method *meth;
-       unsigned char *ret = *pret;
-       size_t i;
+    for (i = 0; i < exts->meths_count; i++) {
+        const unsigned char *out = NULL;
+        size_t outlen = 0;
+        meth = exts->meths + i;
 
-       for (i = 0; i < exts->meths_count; i++)
-               {
-               const unsigned char *out = NULL;
-               size_t outlen = 0;
-               meth = exts->meths + i;
+        if (server) {
+            /*
+             * For ServerHello only send extensions present in ClientHello.
+             */
+            if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED))
+                continue;
+            /* If callback absent for server skip it */
+            if (!meth->add_cb)
+                continue;
+        }
+        if (meth->add_cb) {
+            int cb_retval = 0;
+            cb_retval = meth->add_cb(s, meth->ext_type,
+                                     &out, &outlen, al, meth->add_arg);
+            if (cb_retval < 0)
+                return 0;       /* error */
+            if (cb_retval == 0)
+                continue;       /* skip this extension */
+        }
+        if (4 > limit - ret || outlen > (size_t)(limit - ret - 4))
+            return 0;
+        s2n(meth->ext_type, ret);
+        s2n(outlen, ret);
+        if (outlen) {
+            memcpy(ret, out, outlen);
+            ret += outlen;
+        }
+        /*
+         * We can't send duplicates: code logic should prevent this.
+         */
+        OPENSSL_assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT));
+        /*
+         * Indicate extension has been sent: this is both a sanity check to
+         * ensure we don't send duplicate extensions and indicates that it is
+         * not an error if the extension is present in ServerHello.
+         */
+        meth->ext_flags |= SSL_EXT_FLAG_SENT;
+        if (meth->free_cb)
+            meth->free_cb(s, meth->ext_type, out, meth->add_arg);
+    }
+    *pret = ret;
+    return 1;
+}
 
-               if (server)
-                       {
-                       /* For ServerHello only send extensions present
-                        * in ClientHello.
-                        */
-                       if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED))
-                               continue;
-                       /* If callback absent for server skip it */
-                       if (!meth->add_cb)
-                               continue;
-                       }
-               if (meth->add_cb)
-                       {
-                       int cb_retval = 0;
-                       cb_retval = meth->add_cb(s, meth->ext_type,
-                                                       &out, &outlen, al,
-                                                       meth->add_arg);
-                       if (cb_retval < 0)
-                               return 0; /* error */
-                       if (cb_retval == 0)
-                                       continue; /* skip this extension */
-                       }
-               if (4 > limit - ret || outlen > (size_t)(limit - ret - 4))
-                       return 0;
-               s2n(meth->ext_type, ret);
-               s2n(outlen, ret);
-               if (outlen)
-                       {
-                       memcpy(ret, out, outlen);
-                       ret += outlen;
-                       }
-               /* We can't send duplicates: code logic should prevent this */
-               OPENSSL_assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT));
-               /* Indicate extension has been sent: this is both a sanity
-                * check to ensure we don't send duplicate extensions
-                * and indicates to servers that an extension can be
-                * sent in ServerHello.
-                */
-               meth->ext_flags |= SSL_EXT_FLAG_SENT;
-               if (meth->free_cb)
-                       meth->free_cb(s, meth->ext_type, out, meth->add_arg);
-               }
-       *pret = ret;
-       return 1;
-       }
 
-/* Copy table of custom extensions */
+/*
+ * Request custom extension data from the application and add to the return
+ * buffer.
+ */
+int custom_ext_add(SSL *s, int server, PACKETW *pkt, int *al)
+{
+    custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
+    custom_ext_method *meth;
+    size_t i;
+
+    for (i = 0; i < exts->meths_count; i++) {
+        const unsigned char *out = NULL;
+        size_t outlen = 0;
+        PACKETW spkt;
+
+        meth = exts->meths + i;
 
+        if (server) {
+            /*
+             * For ServerHello only send extensions present in ClientHello.
+             */
+            if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED))
+                continue;
+            /* If callback absent for server skip it */
+            if (!meth->add_cb)
+                continue;
+        }
+        if (meth->add_cb) {
+            int cb_retval = 0;
+            cb_retval = meth->add_cb(s, meth->ext_type,
+                                     &out, &outlen, al, meth->add_arg);
+            if (cb_retval < 0)
+                return 0;       /* error */
+            if (cb_retval == 0)
+                continue;       /* skip this extension */
+        }
+
+        if (!PACKETW_put_bytes(pkt, meth->ext_type, 2)
+                || !PACKETW_get_sub_packet_len(pkt, &spkt, 2)
+                || (outlen > 0 && !PACKETW_memcpy(&spkt, out, outlen))
+                || !PACKETW_close(&spkt)) {
+            *al = SSL_AD_INTERNAL_ERROR;
+            return 0;
+        }
+        /*
+         * We can't send duplicates: code logic should prevent this.
+         */
+        OPENSSL_assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT));
+        /*
+         * Indicate extension has been sent: this is both a sanity check to
+         * ensure we don't send duplicate extensions and indicates that it is
+         * not an error if the extension is present in ServerHello.
+         */
+        meth->ext_flags |= SSL_EXT_FLAG_SENT;
+        if (meth->free_cb)
+            meth->free_cb(s, meth->ext_type, out, meth->add_arg);
+    }
+    return 1;
+}
+
+/* Copy table of custom extensions */
 int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src)
-       {
-       if (src->meths_count)
-               {
-               dst->meths = BUF_memdup(src->meths, sizeof(custom_ext_method) * src->meths_count);
-               if (dst->meths == NULL)
-                       return 0;
-               dst->meths_count = src->meths_count;
-               }
-       return 1;
-       }
+{
+    if (src->meths_count) {
+        dst->meths =
+            OPENSSL_memdup(src->meths,
+                           sizeof(custom_ext_method) * src->meths_count);
+        if (dst->meths == NULL)
+            return 0;
+        dst->meths_count = src->meths_count;
+    }
+    return 1;
+}
 
 void custom_exts_free(custom_ext_methods *exts)
-       {
-       if (exts->meths)
-               OPENSSL_free(exts->meths);
-       }
+{
+    OPENSSL_free(exts->meths);
+}
 
-/* Set callbacks for a custom extension */
-static int custom_ext_set(custom_ext_methods *exts,
-                       unsigned int ext_type,
-                       custom_ext_add_cb add_cb,
-                       custom_ext_free_cb free_cb,
-                       void *add_arg,
-                       custom_ext_parse_cb parse_cb, void *parse_arg)
-       {
-       custom_ext_method *meth;
-       /* See if it is a supported internally */
-       switch(ext_type)
-               {
-       case TLSEXT_TYPE_application_layer_protocol_negotiation:
-       case TLSEXT_TYPE_ec_point_formats:
-       case TLSEXT_TYPE_elliptic_curves:
-       case TLSEXT_TYPE_heartbeat:
-       case TLSEXT_TYPE_next_proto_neg:
-       case TLSEXT_TYPE_padding:
-       case TLSEXT_TYPE_renegotiate:
-       case TLSEXT_TYPE_server_name:
-       case TLSEXT_TYPE_session_ticket:
-       case TLSEXT_TYPE_signature_algorithms:
-       case TLSEXT_TYPE_srp:
-       case TLSEXT_TYPE_status_request:
-       case TLSEXT_TYPE_use_srtp:
-#ifdef TLSEXT_TYPE_opaque_prf_input
-       case TLSEXT_TYPE_opaque_prf_input:
-#endif
-#ifdef TLSEXT_TYPE_encrypt_then_mac
-       case TLSEXT_TYPE_encrypt_then_mac:
-#endif
-               return 0;
-               }
-       /* Extension type must fit in 16 bits */
-       if (ext_type > 0xffff)
-               return 0;
-       /* Search for duplicate */
-       if (custom_ext_find(exts, ext_type))
-               return 0;
-       exts->meths = OPENSSL_realloc(exts->meths,
-                                       (exts->meths_count + 1) * sizeof(custom_ext_method));
+/* Set callbacks for a custom extension. */
+static int custom_ext_meth_add(custom_ext_methods *exts,
+                               unsigned int ext_type,
+                               custom_ext_add_cb add_cb,
+                               custom_ext_free_cb free_cb,
+                               void *add_arg,
+                               custom_ext_parse_cb parse_cb, void *parse_arg)
+{
+    custom_ext_method *meth, *tmp;
+    /*
+     * Check application error: if add_cb is not set free_cb will never be
+     * called.
+     */
+    if (!add_cb && free_cb)
+        return 0;
+    /*
+     * Don't add if extension supported internally, but make exception
+     * for extension types that previously were not supported, but now are.
+     */
+    if (SSL_extension_supported(ext_type) &&
+        ext_type != TLSEXT_TYPE_signed_certificate_timestamp)
+        return 0;
+    /* Extension type must fit in 16 bits */
+    if (ext_type > 0xffff)
+        return 0;
+    /* Search for duplicate */
+    if (custom_ext_find(exts, ext_type))
+        return 0;
+    tmp = OPENSSL_realloc(exts->meths,
+                          (exts->meths_count + 1) * sizeof(custom_ext_method));
 
-       if (!exts->meths)
-               {
-               exts->meths_count = 0;
-               return 0;
-               }
+    if (tmp == NULL) {
+        OPENSSL_free(exts->meths);
+        exts->meths = NULL;
+        exts->meths_count = 0;
+        return 0;
+    }
 
-       meth = exts->meths + exts->meths_count;
-       memset(meth, 0, sizeof(custom_ext_method));
-       meth->parse_cb = parse_cb;
-       meth->add_cb = add_cb;
-       meth->free_cb = free_cb;
-       meth->ext_type = ext_type;
-       meth->add_arg = add_arg;
-       meth->parse_arg = parse_arg;
-       exts->meths_count++;
-       return 1;
-       }
+    exts->meths = tmp;
+    meth = exts->meths + exts->meths_count;
+    memset(meth, 0, sizeof(*meth));
+    meth->parse_cb = parse_cb;
+    meth->add_cb = add_cb;
+    meth->free_cb = free_cb;
+    meth->ext_type = ext_type;
+    meth->add_arg = add_arg;
+    meth->parse_arg = parse_arg;
+    exts->meths_count++;
+    return 1;
+}
 
-/* Application level functions to add custom extension callbacks */
+/* Return true if a client custom extension exists, false otherwise */
+int SSL_CTX_has_client_custom_ext(const SSL_CTX *ctx, unsigned int ext_type)
+{
+    return custom_ext_find(&ctx->cert->cli_ext, ext_type) != NULL;
+}
 
-int SSL_CTX_set_custom_cli_ext(SSL_CTX *ctx, unsigned int ext_type,
-                              custom_ext_add_cb add_cb,
-                              custom_ext_free_cb free_cb,
-                               void *add_arg,
-                              custom_ext_parse_cb parse_cb, void *parse_arg)
+/* Application level functions to add custom extension callbacks */
+int SSL_CTX_add_client_custom_ext(SSL_CTX *ctx, unsigned int ext_type,
+                                  custom_ext_add_cb add_cb,
+                                  custom_ext_free_cb free_cb,
+                                  void *add_arg,
+                                  custom_ext_parse_cb parse_cb, void *parse_arg)
+{
+#ifndef OPENSSL_NO_CT
+    /*
+     * We don't want applications registering callbacks for SCT extensions
+     * whilst simultaneously using the built-in SCT validation features, as
+     * these two things may not play well together.
+     */
+    if (ext_type == TLSEXT_TYPE_signed_certificate_timestamp &&
+        SSL_CTX_ct_is_enabled(ctx))
+        return 0;
+#endif
+    return custom_ext_meth_add(&ctx->cert->cli_ext, ext_type, add_cb,
+                               free_cb, add_arg, parse_cb, parse_arg);
+}
 
-       {
-       return custom_ext_set(&ctx->cert->cli_ext, ext_type,
-                               add_cb, free_cb, add_arg,
-                               parse_cb, parse_arg);
-       }
+int SSL_CTX_add_server_custom_ext(SSL_CTX *ctx, unsigned int ext_type,
+                                  custom_ext_add_cb add_cb,
+                                  custom_ext_free_cb free_cb,
+                                  void *add_arg,
+                                  custom_ext_parse_cb parse_cb, void *parse_arg)
+{
+    return custom_ext_meth_add(&ctx->cert->srv_ext, ext_type,
+                               add_cb, free_cb, add_arg, parse_cb, parse_arg);
+}
 
-int SSL_CTX_set_custom_srv_ext(SSL_CTX *ctx, unsigned int ext_type,
-                              custom_ext_add_cb add_cb,
-                              custom_ext_free_cb free_cb,
-                               void *add_arg,
-                              custom_ext_parse_cb parse_cb, void *parse_arg)
-       {
-       return custom_ext_set(&ctx->cert->srv_ext, ext_type,
-                               add_cb, free_cb, add_arg,
-                               parse_cb, parse_arg);
-       }
+int SSL_extension_supported(unsigned int ext_type)
+{
+    switch (ext_type) {
+        /* Internally supported extensions. */
+    case TLSEXT_TYPE_application_layer_protocol_negotiation:
+    case TLSEXT_TYPE_ec_point_formats:
+    case TLSEXT_TYPE_elliptic_curves:
+    case TLSEXT_TYPE_heartbeat:
+#ifndef OPENSSL_NO_NEXTPROTONEG
+    case TLSEXT_TYPE_next_proto_neg:
+#endif
+    case TLSEXT_TYPE_padding:
+    case TLSEXT_TYPE_renegotiate:
+    case TLSEXT_TYPE_server_name:
+    case TLSEXT_TYPE_session_ticket:
+    case TLSEXT_TYPE_signature_algorithms:
+    case TLSEXT_TYPE_srp:
+    case TLSEXT_TYPE_status_request:
+    case TLSEXT_TYPE_signed_certificate_timestamp:
+    case TLSEXT_TYPE_use_srtp:
+#ifdef TLSEXT_TYPE_encrypt_then_mac
+    case TLSEXT_TYPE_encrypt_then_mac:
 #endif
+        return 1;
+    default:
+        return 0;
+    }
+}