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tls_ffdhe.c
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tls_ffdhe.c
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/**
* @file tls_ffdhe.c
* @brief FFDHE key exchange
*
* @section License
*
* SPDX-License-Identifier: GPL-2.0-or-later
*
* Copyright (C) 2010-2022 Oryx Embedded SARL. All rights reserved.
*
* This file is part of CycloneSSL Open.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* @author Oryx Embedded SARL (www.oryx-embedded.com)
* @version 2.1.4
**/
//Switch to the appropriate trace level
#define TRACE_LEVEL TLS_TRACE_LEVEL
//Dependencies
#include <string.h>
#include "tls.h"
#include "tls_ffdhe.h"
#include "debug.h"
//Check TLS library configuration
#if (TLS_SUPPORT == ENABLED && TLS_FFDHE_SUPPORT == ENABLED)
#if (TLS_FFDHE2048_SUPPORT == ENABLED)
/**
* @brief ffdhe2048 group
**/
const TlsFfdheGroup ffdhe2048Group =
{
//Group name
"ffdhe2048",
//Prime modulus
{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xAD, 0xF8, 0x54, 0x58, 0xA2, 0xBB, 0x4A, 0x9A,
0xAF, 0xDC, 0x56, 0x20, 0x27, 0x3D, 0x3C, 0xF1, 0xD8, 0xB9, 0xC5, 0x83, 0xCE, 0x2D, 0x36, 0x95,
0xA9, 0xE1, 0x36, 0x41, 0x14, 0x64, 0x33, 0xFB, 0xCC, 0x93, 0x9D, 0xCE, 0x24, 0x9B, 0x3E, 0xF9,
0x7D, 0x2F, 0xE3, 0x63, 0x63, 0x0C, 0x75, 0xD8, 0xF6, 0x81, 0xB2, 0x02, 0xAE, 0xC4, 0x61, 0x7A,
0xD3, 0xDF, 0x1E, 0xD5, 0xD5, 0xFD, 0x65, 0x61, 0x24, 0x33, 0xF5, 0x1F, 0x5F, 0x06, 0x6E, 0xD0,
0x85, 0x63, 0x65, 0x55, 0x3D, 0xED, 0x1A, 0xF3, 0xB5, 0x57, 0x13, 0x5E, 0x7F, 0x57, 0xC9, 0x35,
0x98, 0x4F, 0x0C, 0x70, 0xE0, 0xE6, 0x8B, 0x77, 0xE2, 0xA6, 0x89, 0xDA, 0xF3, 0xEF, 0xE8, 0x72,
0x1D, 0xF1, 0x58, 0xA1, 0x36, 0xAD, 0xE7, 0x35, 0x30, 0xAC, 0xCA, 0x4F, 0x48, 0x3A, 0x79, 0x7A,
0xBC, 0x0A, 0xB1, 0x82, 0xB3, 0x24, 0xFB, 0x61, 0xD1, 0x08, 0xA9, 0x4B, 0xB2, 0xC8, 0xE3, 0xFB,
0xB9, 0x6A, 0xDA, 0xB7, 0x60, 0xD7, 0xF4, 0x68, 0x1D, 0x4F, 0x42, 0xA3, 0xDE, 0x39, 0x4D, 0xF4,
0xAE, 0x56, 0xED, 0xE7, 0x63, 0x72, 0xBB, 0x19, 0x0B, 0x07, 0xA7, 0xC8, 0xEE, 0x0A, 0x6D, 0x70,
0x9E, 0x02, 0xFC, 0xE1, 0xCD, 0xF7, 0xE2, 0xEC, 0xC0, 0x34, 0x04, 0xCD, 0x28, 0x34, 0x2F, 0x61,
0x91, 0x72, 0xFE, 0x9C, 0xE9, 0x85, 0x83, 0xFF, 0x8E, 0x4F, 0x12, 0x32, 0xEE, 0xF2, 0x81, 0x83,
0xC3, 0xFE, 0x3B, 0x1B, 0x4C, 0x6F, 0xAD, 0x73, 0x3B, 0xB5, 0xFC, 0xBC, 0x2E, 0xC2, 0x20, 0x05,
0xC5, 0x8E, 0xF1, 0x83, 0x7D, 0x16, 0x83, 0xB2, 0xC6, 0xF3, 0x4A, 0x26, 0xC1, 0xB2, 0xEF, 0xFA,
0x88, 0x6B, 0x42, 0x38, 0x61, 0x28, 0x5C, 0x97, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
256,
//Generator
2
};
#endif
#if (TLS_FFDHE3072_SUPPORT == ENABLED)
/**
* @brief ffdhe3072 group
**/
const TlsFfdheGroup ffdhe3072Group =
{
//Group name
"ffdhe3072",
//Prime modulus
{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xAD, 0xF8, 0x54, 0x58, 0xA2, 0xBB, 0x4A, 0x9A,
0xAF, 0xDC, 0x56, 0x20, 0x27, 0x3D, 0x3C, 0xF1, 0xD8, 0xB9, 0xC5, 0x83, 0xCE, 0x2D, 0x36, 0x95,
0xA9, 0xE1, 0x36, 0x41, 0x14, 0x64, 0x33, 0xFB, 0xCC, 0x93, 0x9D, 0xCE, 0x24, 0x9B, 0x3E, 0xF9,
0x7D, 0x2F, 0xE3, 0x63, 0x63, 0x0C, 0x75, 0xD8, 0xF6, 0x81, 0xB2, 0x02, 0xAE, 0xC4, 0x61, 0x7A,
0xD3, 0xDF, 0x1E, 0xD5, 0xD5, 0xFD, 0x65, 0x61, 0x24, 0x33, 0xF5, 0x1F, 0x5F, 0x06, 0x6E, 0xD0,
0x85, 0x63, 0x65, 0x55, 0x3D, 0xED, 0x1A, 0xF3, 0xB5, 0x57, 0x13, 0x5E, 0x7F, 0x57, 0xC9, 0x35,
0x98, 0x4F, 0x0C, 0x70, 0xE0, 0xE6, 0x8B, 0x77, 0xE2, 0xA6, 0x89, 0xDA, 0xF3, 0xEF, 0xE8, 0x72,
0x1D, 0xF1, 0x58, 0xA1, 0x36, 0xAD, 0xE7, 0x35, 0x30, 0xAC, 0xCA, 0x4F, 0x48, 0x3A, 0x79, 0x7A,
0xBC, 0x0A, 0xB1, 0x82, 0xB3, 0x24, 0xFB, 0x61, 0xD1, 0x08, 0xA9, 0x4B, 0xB2, 0xC8, 0xE3, 0xFB,
0xB9, 0x6A, 0xDA, 0xB7, 0x60, 0xD7, 0xF4, 0x68, 0x1D, 0x4F, 0x42, 0xA3, 0xDE, 0x39, 0x4D, 0xF4,
0xAE, 0x56, 0xED, 0xE7, 0x63, 0x72, 0xBB, 0x19, 0x0B, 0x07, 0xA7, 0xC8, 0xEE, 0x0A, 0x6D, 0x70,
0x9E, 0x02, 0xFC, 0xE1, 0xCD, 0xF7, 0xE2, 0xEC, 0xC0, 0x34, 0x04, 0xCD, 0x28, 0x34, 0x2F, 0x61,
0x91, 0x72, 0xFE, 0x9C, 0xE9, 0x85, 0x83, 0xFF, 0x8E, 0x4F, 0x12, 0x32, 0xEE, 0xF2, 0x81, 0x83,
0xC3, 0xFE, 0x3B, 0x1B, 0x4C, 0x6F, 0xAD, 0x73, 0x3B, 0xB5, 0xFC, 0xBC, 0x2E, 0xC2, 0x20, 0x05,
0xC5, 0x8E, 0xF1, 0x83, 0x7D, 0x16, 0x83, 0xB2, 0xC6, 0xF3, 0x4A, 0x26, 0xC1, 0xB2, 0xEF, 0xFA,
0x88, 0x6B, 0x42, 0x38, 0x61, 0x1F, 0xCF, 0xDC, 0xDE, 0x35, 0x5B, 0x3B, 0x65, 0x19, 0x03, 0x5B,
0xBC, 0x34, 0xF4, 0xDE, 0xF9, 0x9C, 0x02, 0x38, 0x61, 0xB4, 0x6F, 0xC9, 0xD6, 0xE6, 0xC9, 0x07,
0x7A, 0xD9, 0x1D, 0x26, 0x91, 0xF7, 0xF7, 0xEE, 0x59, 0x8C, 0xB0, 0xFA, 0xC1, 0x86, 0xD9, 0x1C,
0xAE, 0xFE, 0x13, 0x09, 0x85, 0x13, 0x92, 0x70, 0xB4, 0x13, 0x0C, 0x93, 0xBC, 0x43, 0x79, 0x44,
0xF4, 0xFD, 0x44, 0x52, 0xE2, 0xD7, 0x4D, 0xD3, 0x64, 0xF2, 0xE2, 0x1E, 0x71, 0xF5, 0x4B, 0xFF,
0x5C, 0xAE, 0x82, 0xAB, 0x9C, 0x9D, 0xF6, 0x9E, 0xE8, 0x6D, 0x2B, 0xC5, 0x22, 0x36, 0x3A, 0x0D,
0xAB, 0xC5, 0x21, 0x97, 0x9B, 0x0D, 0xEA, 0xDA, 0x1D, 0xBF, 0x9A, 0x42, 0xD5, 0xC4, 0x48, 0x4E,
0x0A, 0xBC, 0xD0, 0x6B, 0xFA, 0x53, 0xDD, 0xEF, 0x3C, 0x1B, 0x20, 0xEE, 0x3F, 0xD5, 0x9D, 0x7C,
0x25, 0xE4, 0x1D, 0x2B, 0x66, 0xC6, 0x2E, 0x37, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
384,
//Generator
2
};
#endif
#if (TLS_FFDHE4096_SUPPORT == ENABLED)
/**
* @brief ffdhe4096 group
**/
const TlsFfdheGroup ffdhe4096Group =
{
//Group name
"ffdhe4096",
//Prime modulus
{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xAD, 0xF8, 0x54, 0x58, 0xA2, 0xBB, 0x4A, 0x9A,
0xAF, 0xDC, 0x56, 0x20, 0x27, 0x3D, 0x3C, 0xF1, 0xD8, 0xB9, 0xC5, 0x83, 0xCE, 0x2D, 0x36, 0x95,
0xA9, 0xE1, 0x36, 0x41, 0x14, 0x64, 0x33, 0xFB, 0xCC, 0x93, 0x9D, 0xCE, 0x24, 0x9B, 0x3E, 0xF9,
0x7D, 0x2F, 0xE3, 0x63, 0x63, 0x0C, 0x75, 0xD8, 0xF6, 0x81, 0xB2, 0x02, 0xAE, 0xC4, 0x61, 0x7A,
0xD3, 0xDF, 0x1E, 0xD5, 0xD5, 0xFD, 0x65, 0x61, 0x24, 0x33, 0xF5, 0x1F, 0x5F, 0x06, 0x6E, 0xD0,
0x85, 0x63, 0x65, 0x55, 0x3D, 0xED, 0x1A, 0xF3, 0xB5, 0x57, 0x13, 0x5E, 0x7F, 0x57, 0xC9, 0x35,
0x98, 0x4F, 0x0C, 0x70, 0xE0, 0xE6, 0x8B, 0x77, 0xE2, 0xA6, 0x89, 0xDA, 0xF3, 0xEF, 0xE8, 0x72,
0x1D, 0xF1, 0x58, 0xA1, 0x36, 0xAD, 0xE7, 0x35, 0x30, 0xAC, 0xCA, 0x4F, 0x48, 0x3A, 0x79, 0x7A,
0xBC, 0x0A, 0xB1, 0x82, 0xB3, 0x24, 0xFB, 0x61, 0xD1, 0x08, 0xA9, 0x4B, 0xB2, 0xC8, 0xE3, 0xFB,
0xB9, 0x6A, 0xDA, 0xB7, 0x60, 0xD7, 0xF4, 0x68, 0x1D, 0x4F, 0x42, 0xA3, 0xDE, 0x39, 0x4D, 0xF4,
0xAE, 0x56, 0xED, 0xE7, 0x63, 0x72, 0xBB, 0x19, 0x0B, 0x07, 0xA7, 0xC8, 0xEE, 0x0A, 0x6D, 0x70,
0x9E, 0x02, 0xFC, 0xE1, 0xCD, 0xF7, 0xE2, 0xEC, 0xC0, 0x34, 0x04, 0xCD, 0x28, 0x34, 0x2F, 0x61,
0x91, 0x72, 0xFE, 0x9C, 0xE9, 0x85, 0x83, 0xFF, 0x8E, 0x4F, 0x12, 0x32, 0xEE, 0xF2, 0x81, 0x83,
0xC3, 0xFE, 0x3B, 0x1B, 0x4C, 0x6F, 0xAD, 0x73, 0x3B, 0xB5, 0xFC, 0xBC, 0x2E, 0xC2, 0x20, 0x05,
0xC5, 0x8E, 0xF1, 0x83, 0x7D, 0x16, 0x83, 0xB2, 0xC6, 0xF3, 0x4A, 0x26, 0xC1, 0xB2, 0xEF, 0xFA,
0x88, 0x6B, 0x42, 0x38, 0x61, 0x1F, 0xCF, 0xDC, 0xDE, 0x35, 0x5B, 0x3B, 0x65, 0x19, 0x03, 0x5B,
0xBC, 0x34, 0xF4, 0xDE, 0xF9, 0x9C, 0x02, 0x38, 0x61, 0xB4, 0x6F, 0xC9, 0xD6, 0xE6, 0xC9, 0x07,
0x7A, 0xD9, 0x1D, 0x26, 0x91, 0xF7, 0xF7, 0xEE, 0x59, 0x8C, 0xB0, 0xFA, 0xC1, 0x86, 0xD9, 0x1C,
0xAE, 0xFE, 0x13, 0x09, 0x85, 0x13, 0x92, 0x70, 0xB4, 0x13, 0x0C, 0x93, 0xBC, 0x43, 0x79, 0x44,
0xF4, 0xFD, 0x44, 0x52, 0xE2, 0xD7, 0x4D, 0xD3, 0x64, 0xF2, 0xE2, 0x1E, 0x71, 0xF5, 0x4B, 0xFF,
0x5C, 0xAE, 0x82, 0xAB, 0x9C, 0x9D, 0xF6, 0x9E, 0xE8, 0x6D, 0x2B, 0xC5, 0x22, 0x36, 0x3A, 0x0D,
0xAB, 0xC5, 0x21, 0x97, 0x9B, 0x0D, 0xEA, 0xDA, 0x1D, 0xBF, 0x9A, 0x42, 0xD5, 0xC4, 0x48, 0x4E,
0x0A, 0xBC, 0xD0, 0x6B, 0xFA, 0x53, 0xDD, 0xEF, 0x3C, 0x1B, 0x20, 0xEE, 0x3F, 0xD5, 0x9D, 0x7C,
0x25, 0xE4, 0x1D, 0x2B, 0x66, 0x9E, 0x1E, 0xF1, 0x6E, 0x6F, 0x52, 0xC3, 0x16, 0x4D, 0xF4, 0xFB,
0x79, 0x30, 0xE9, 0xE4, 0xE5, 0x88, 0x57, 0xB6, 0xAC, 0x7D, 0x5F, 0x42, 0xD6, 0x9F, 0x6D, 0x18,
0x77, 0x63, 0xCF, 0x1D, 0x55, 0x03, 0x40, 0x04, 0x87, 0xF5, 0x5B, 0xA5, 0x7E, 0x31, 0xCC, 0x7A,
0x71, 0x35, 0xC8, 0x86, 0xEF, 0xB4, 0x31, 0x8A, 0xED, 0x6A, 0x1E, 0x01, 0x2D, 0x9E, 0x68, 0x32,
0xA9, 0x07, 0x60, 0x0A, 0x91, 0x81, 0x30, 0xC4, 0x6D, 0xC7, 0x78, 0xF9, 0x71, 0xAD, 0x00, 0x38,
0x09, 0x29, 0x99, 0xA3, 0x33, 0xCB, 0x8B, 0x7A, 0x1A, 0x1D, 0xB9, 0x3D, 0x71, 0x40, 0x00, 0x3C,
0x2A, 0x4E, 0xCE, 0xA9, 0xF9, 0x8D, 0x0A, 0xCC, 0x0A, 0x82, 0x91, 0xCD, 0xCE, 0xC9, 0x7D, 0xCF,
0x8E, 0xC9, 0xB5, 0x5A, 0x7F, 0x88, 0xA4, 0x6B, 0x4D, 0xB5, 0xA8, 0x51, 0xF4, 0x41, 0x82, 0xE1,
0xC6, 0x8A, 0x00, 0x7E, 0x5E, 0x65, 0x5F, 0x6A, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
512,
//Generator
2
};
#endif
/**
* @brief Select the named group to be used when performing FFDHE key exchange
* @param[in] context Pointer to the TLS context
* @param[in] groupList List of named groups supported by the peer
* @return Error code
**/
error_t tlsSelectFfdheGroup(TlsContext *context,
const TlsSupportedGroupList *groupList)
{
error_t error;
uint_t i;
uint_t j;
uint_t n;
uint16_t namedGroup;
bool_t ffdheGroupFound;
//Initialize status code
error = ERROR_HANDSHAKE_FAILED;
//Initialize flag
ffdheGroupFound = FALSE;
//Reset the named group to its default value
context->namedGroup = TLS_GROUP_NONE;
//Check whether a list of named groups is offered by the client
if(groupList != NULL)
{
//Get the number of named groups present in the list
n = ntohs(groupList->length) / sizeof(uint16_t);
//Any preferred groups?
if(context->numSupportedGroups > 0)
{
//Loop through the list of allowed groups (most preferred first)
for(i = 0; i < context->numSupportedGroups; i++)
{
//Loop through the list of named groups the client supports
for(j = 0; j < n; j++)
{
//Convert the named group to host byte order
namedGroup = ntohs(groupList->value[j]);
//Check whether the SupportedGroups extension contains codepoints
//between 256 and 511, inclusive
if(namedGroup >= TLS_GROUP_FFDHE2048 &&
namedGroup <= TLS_GROUP_FFDHE_MAX)
{
//The list contains at least one FFDHE group
ffdheGroupFound = TRUE;
}
//The named group to be used when performing FFDHE key exchange
//must be one of those present in the SupportedGroups extension
if(context->supportedGroups[i] == namedGroup)
{
//Acceptable FFDHE group found?
if(tlsGetFfdheGroup(context, namedGroup) != NULL)
{
//Save the named group
if(context->namedGroup == TLS_GROUP_NONE)
{
context->namedGroup = namedGroup;
}
}
}
}
}
}
else
{
//The named group to be used when performing FFDHE key exchange must
//be one of those present in the SupportedGroups extension
for(j = 0; j < n; j++)
{
//Convert the named group to host byte order
namedGroup = ntohs(groupList->value[j]);
//Check whether the SupportedGroups extension contains codepoints
//between 256 and 511, inclusive
if(namedGroup >= TLS_GROUP_FFDHE2048 &&
namedGroup <= TLS_GROUP_FFDHE_MAX)
{
//The list contains at least one FFDHE group
ffdheGroupFound = TRUE;
}
//Acceptable FFDHE group found?
if(tlsGetFfdheGroup(context, namedGroup) != NULL)
{
//Save the named group
if(context->namedGroup == TLS_GROUP_NONE)
{
context->namedGroup = namedGroup;
}
}
}
}
}
//If the SupportedGroups extension is either absent from the ClientHello
//entirely or contains no FFDHE groups, then the server knows that the
//client is not compatible with RFC 7919
if(!ffdheGroupFound)
{
//In this scenario, the server may select an FFDHE group of its choice
if(tlsGetFfdheGroup(context, TLS_GROUP_FFDHE2048) != NULL)
{
//Select ffdhe2048 finite field group
context->namedGroup = TLS_GROUP_FFDHE2048;
}
else if(tlsGetFfdheGroup(context, TLS_GROUP_FFDHE3072) != NULL)
{
//Select ffdhe3072 finite field group
context->namedGroup = TLS_GROUP_FFDHE3072;
}
else if(tlsGetFfdheGroup(context, TLS_GROUP_FFDHE4096) != NULL)
{
//Select ffdhe4096 finite field group
context->namedGroup = TLS_GROUP_FFDHE4096;
}
else
{
//Just for sanity
context->namedGroup = TLS_GROUP_NONE;
}
}
//If no acceptable choices are presented, then return an error
if(context->namedGroup != TLS_GROUP_NONE)
{
error = NO_ERROR;
}
//Return status code
return error;
}
/**
* @brief Get the FFDHE parameters that match the specified named group
* @param[in] context Pointer to the TLS context
* @param[in] namedGroup Named group
* @return FFDHE parameters
**/
const TlsFfdheGroup *tlsGetFfdheGroup(TlsContext *context, uint16_t namedGroup)
{
uint_t i;
const TlsFfdheGroup *ffdheGroup;
//Check named group
switch(namedGroup)
{
#if (TLS_FFDHE2048_SUPPORT == ENABLED)
//ffdhe2048 group?
case TLS_GROUP_FFDHE2048:
ffdheGroup = &ffdhe2048Group;
break;
#endif
#if (TLS_FFDHE3072_SUPPORT == ENABLED)
//ffdhe3072 group?
case TLS_GROUP_FFDHE3072:
ffdheGroup = &ffdhe3072Group;
break;
#endif
#if (TLS_FFDHE4096_SUPPORT == ENABLED)
//ffdhe4096 group?
case TLS_GROUP_FFDHE4096:
ffdheGroup = &ffdhe4096Group;
break;
#endif
//Unknown group?
default:
ffdheGroup = NULL;
break;
}
//Restrict the use of certain FFDHE groups
if(context->numSupportedGroups > 0)
{
//Loop through the list of allowed named groups
for(i = 0; i < context->numSupportedGroups; i++)
{
//Compare named groups
if(context->supportedGroups[i] == namedGroup)
break;
}
//Check whether the use of the FFDHE group is restricted
if(i >= context->numSupportedGroups)
ffdheGroup = NULL;
}
//Return FFDHE parameters, if any
return ffdheGroup;
}
/**
* @brief Load FFDHE parameters
* @param[out] params Pointer to the structure to be initialized
* @param[in] ffdheGroup FFDHE parameters
* @return Error code
**/
error_t tlsLoadFfdheParameters(DhParameters *params,
const TlsFfdheGroup *ffdheGroup)
{
error_t error;
//Make sure the FFDHE group is supported
if(ffdheGroup != NULL)
{
//Convert the prime modulus to a multiple precision integer
error = mpiImport(¶ms->p, ffdheGroup->p, ffdheGroup->pLen,
MPI_FORMAT_BIG_ENDIAN);
//Check status code
if(!error)
{
//Convert the generator to a multiple precision integer
error = mpiSetValue(¶ms->g, ffdheGroup->g);
}
}
else
{
//The specified FFDHE group is not supported
error = ERROR_FAILURE;
}
//Return status code
return error;
}
#endif