Show source - SSL/TLS client source code
include/polarssl/ssl.h
/**
* \file ssl.h
*
* Copyright (C) 2006-2010, Brainspark B.V.
*
* This file is part of PolarSSL (http://www.polarssl.org)
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
*
* All rights reserved.
*
* 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.
*/
#ifndef POLARSSL_SSL_H
#define POLARSSL_SSL_H
#include <time.h>
#include "polarssl/net.h"
#include "polarssl/dhm.h"
#include "polarssl/rsa.h"
#include "polarssl/md5.h"
#include "polarssl/sha1.h"
#include "polarssl/x509.h"
/*
* SSL Error codes
*/
#define POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE -0x1000
#define POLARSSL_ERR_SSL_BAD_INPUT_DATA -0x1800
#define POLARSSL_ERR_SSL_INVALID_MAC -0x2000
#define POLARSSL_ERR_SSL_INVALID_RECORD -0x2800
#define POLARSSL_ERR_SSL_INVALID_MODULUS_SIZE -0x3000
#define POLARSSL_ERR_SSL_UNKNOWN_CIPHER -0x3800
#define POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN -0x4000
#define POLARSSL_ERR_SSL_NO_SESSION_FOUND -0x4800
#define POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE -0x5000
#define POLARSSL_ERR_SSL_CERTIFICATE_TOO_LARGE -0x5800
#define POLARSSL_ERR_SSL_CERTIFICATE_REQUIRED -0x6000
#define POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED -0x6800
#define POLARSSL_ERR_SSL_CA_CHAIN_REQUIRED -0x7000
#define POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE -0x7800
#define POLARSSL_ERR_SSL_FATAL_ALERT_MESSAGE -0x8000
#define POLARSSL_ERR_SSL_PEER_VERIFY_FAILED -0x8800
#define POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY -0x9000
#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO -0x9800
#define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO -0xA000
#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE -0xA800
#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0xB000
#define POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0xB800
#define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0xC000
#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0xC800
#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0xD000
#define POLARSSL_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0xD800
#define POLARSSL_ERR_SSL_BAD_HS_FINISHED -0xE000
/*
* Various constants
*/
#define SSL_MAJOR_VERSION_3 3
#define SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */
#define SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */
#define SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */
#define SSL_IS_CLIENT 0
#define SSL_IS_SERVER 1
#define SSL_COMPRESS_NULL 0
#define SSL_VERIFY_NONE 0
#define SSL_VERIFY_OPTIONAL 1
#define SSL_VERIFY_REQUIRED 2
#define SSL_MAX_CONTENT_LEN 16384
/*
* Allow an extra 512 bytes for the record header
* and encryption overhead (counter + MAC + padding).
*/
#define SSL_BUFFER_LEN (SSL_MAX_CONTENT_LEN + 512)
/*
* Supported ciphersuites
*/
#define SSL_RSA_RC4_128_MD5 0x04
#define SSL_RSA_RC4_128_SHA 0x05
#define SSL_RSA_DES_168_SHA 0x0A
#define SSL_EDH_RSA_DES_168_SHA 0x16
#define SSL_RSA_AES_128_SHA 0x2F
#define SSL_EDH_RSA_AES_128_SHA 0x33
#define SSL_RSA_AES_256_SHA 0x35
#define SSL_EDH_RSA_AES_256_SHA 0x39
#define SSL_RSA_CAMELLIA_128_SHA 0x41
#define SSL_EDH_RSA_CAMELLIA_128_SHA 0x45
#define SSL_RSA_CAMELLIA_256_SHA 0x84
#define SSL_EDH_RSA_CAMELLIA_256_SHA 0x88
/*
* Message, alert and handshake types
*/
#define SSL_MSG_CHANGE_CIPHER_SPEC 20
#define SSL_MSG_ALERT 21
#define SSL_MSG_HANDSHAKE 22
#define SSL_MSG_APPLICATION_DATA 23
#define SSL_ALERT_LEVEL_WARNING 1
#define SSL_ALERT_LEVEL_FATAL 2
#define SSL_ALERT_MSG_CLOSE_NOTIFY 0
#define SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10
#define SSL_ALERT_MSG_BAD_RECORD_MAD 20
#define SSL_ALERT_MSG_DECRYPTION_FAILED 21
#define SSL_ALERT_MSG_RECORD_OVERFLOW 22
#define SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30
#define SSL_ALERT_MSG_HANDSHAKE_FAILURE 40
#define SSL_ALERT_MSG_NO_CERT 41
#define SSL_ALERT_MSG_BAD_CERT 42
#define SSL_ALERT_MSG_UNSUPPORTED_CERT 43
#define SSL_ALERT_MSG_CERT_REVOKED 44
#define SSL_ALERT_MSG_CERT_EXPIRED 45
#define SSL_ALERT_MSG_CERT_UNKNOWN 46
#define SSL_ALERT_MSG_ILLEGAL_PARAMETER 47
#define SSL_ALERT_MSG_UNKNOWN_CA 48
#define SSL_ALERT_MSG_ACCESS_DENIED 49
#define SSL_ALERT_MSG_DECODE_ERROR 50
#define SSL_ALERT_MSG_DECRYPT_ERROR 51
#define SSL_ALERT_MSG_EXPORT_RESTRICTION 60
#define SSL_ALERT_MSG_PROTOCOL_VERSION 70
#define SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71
#define SSL_ALERT_MSG_INTERNAL_ERROR 80
#define SSL_ALERT_MSG_USER_CANCELED 90
#define SSL_ALERT_MSG_NO_RENEGOTIATION 100
#define SSL_HS_HELLO_REQUEST 0
#define SSL_HS_CLIENT_HELLO 1
#define SSL_HS_SERVER_HELLO 2
#define SSL_HS_CERTIFICATE 11
#define SSL_HS_SERVER_KEY_EXCHANGE 12
#define SSL_HS_CERTIFICATE_REQUEST 13
#define SSL_HS_SERVER_HELLO_DONE 14
#define SSL_HS_CERTIFICATE_VERIFY 15
#define SSL_HS_CLIENT_KEY_EXCHANGE 16
#define SSL_HS_FINISHED 20
/*
* TLS extensions
*/
#define TLS_EXT_SERVERNAME 0
#define TLS_EXT_SERVERNAME_HOSTNAME 0
/*
* SSL state machine
*/
typedef enum
{
SSL_HELLO_REQUEST,
SSL_CLIENT_HELLO,
SSL_SERVER_HELLO,
SSL_SERVER_CERTIFICATE,
SSL_SERVER_KEY_EXCHANGE,
SSL_CERTIFICATE_REQUEST,
SSL_SERVER_HELLO_DONE,
SSL_CLIENT_CERTIFICATE,
SSL_CLIENT_KEY_EXCHANGE,
SSL_CERTIFICATE_VERIFY,
SSL_CLIENT_CHANGE_CIPHER_SPEC,
SSL_CLIENT_FINISHED,
SSL_SERVER_CHANGE_CIPHER_SPEC,
SSL_SERVER_FINISHED,
SSL_FLUSH_BUFFERS,
SSL_HANDSHAKE_OVER
}
ssl_states;
typedef struct _ssl_session ssl_session;
typedef struct _ssl_context ssl_context;
/*
* This structure is used for session resuming.
*/
struct _ssl_session
{
time_t start; /*!< starting time */
int cipher; /*!< chosen cipher */
int length; /*!< session id length */
unsigned char id[32]; /*!< session identifier */
unsigned char master[48]; /*!< the master secret */
ssl_session *next; /*!< next session entry */
};
struct _ssl_context
{
/*
* Miscellaneous
*/
int state; /*!< SSL handshake: current state */
int major_ver; /*!< equal to SSL_MAJOR_VERSION_3 */
int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */
int max_major_ver; /*!< max. major version from client */
int max_minor_ver; /*!< max. minor version from client */
/*
* Callbacks (RNG, debug, I/O)
*/
int (*f_rng)(void *);
void (*f_dbg)(void *, int, const char *);
int (*f_recv)(void *, unsigned char *, int);
int (*f_send)(void *, unsigned char *, int);
void *p_rng; /*!< context for the RNG function */
void *p_dbg; /*!< context for the debug function */
void *p_recv; /*!< context for reading operations */
void *p_send; /*!< context for writing operations */
/*
* Session layer
*/
int resume; /*!< session resuming flag */
int timeout; /*!< sess. expiration time */
ssl_session *session; /*!< current session data */
int (*s_get)(ssl_context *); /*!< (server) get callback */
int (*s_set)(ssl_context *); /*!< (server) set callback */
/*
* Record layer (incoming data)
*/
unsigned char *in_ctr; /*!< 64-bit incoming message counter */
unsigned char *in_hdr; /*!< 5-byte record header (in_ctr+8) */
unsigned char *in_msg; /*!< the message contents (in_hdr+5) */
unsigned char *in_offt; /*!< read offset in application data */
int in_msgtype; /*!< record header: message type */
int in_msglen; /*!< record header: message length */
int in_left; /*!< amount of data read so far */
int in_hslen; /*!< current handshake message length */
int nb_zero; /*!< # of 0-length encrypted messages */
/*
* Record layer (outgoing data)
*/
unsigned char *out_ctr; /*!< 64-bit outgoing message counter */
unsigned char *out_hdr; /*!< 5-byte record header (out_ctr+8) */
unsigned char *out_msg; /*!< the message contents (out_hdr+5) */
int out_msgtype; /*!< record header: message type */
int out_msglen; /*!< record header: message length */
int out_left; /*!< amount of data not yet written */
/*
* PKI layer
*/
rsa_context *rsa_key; /*!< own RSA private key */
x509_cert *own_cert; /*!< own X.509 certificate */
x509_cert *ca_chain; /*!< own trusted CA chain */
x509_crl *ca_crl; /*!< trusted CA CRLs */
x509_cert *peer_cert; /*!< peer X.509 cert chain */
const char *peer_cn; /*!< expected peer CN */
int endpoint; /*!< 0: client, 1: server */
int authmode; /*!< verification mode */
int client_auth; /*!< flag for client auth. */
int verify_result; /*!< verification result */
/*
* Crypto layer
*/
dhm_context dhm_ctx; /*!< DHM key exchange */
md5_context fin_md5; /*!< Finished MD5 checksum */
sha1_context fin_sha1; /*!< Finished SHA-1 checksum */
int do_crypt; /*!< en(de)cryption flag */
int *ciphers; /*!< allowed ciphersuites */
int pmslen; /*!< premaster length */
int keylen; /*!< symmetric key length */
int minlen; /*!< min. ciphertext length */
int ivlen; /*!< IV length */
int maclen; /*!< MAC length */
unsigned char randbytes[64]; /*!< random bytes */
unsigned char premaster[256]; /*!< premaster secret */
unsigned char iv_enc[16]; /*!< IV (encryption) */
unsigned char iv_dec[16]; /*!< IV (decryption) */
unsigned char mac_enc[32]; /*!< MAC (encryption) */
unsigned char mac_dec[32]; /*!< MAC (decryption) */
unsigned long ctx_enc[128]; /*!< encryption context */
unsigned long ctx_dec[128]; /*!< decryption context */
/*
* TLS extensions
*/
unsigned char *hostname;
unsigned long hostname_len;
};
#ifdef __cplusplus
extern "C" {
#endif
extern int ssl_default_ciphers[];
/**
* \brief Initialize an SSL context
*
* \param ssl SSL context
*
* \return 0 if successful, or 1 if memory allocation failed
*/
int ssl_init( ssl_context *ssl );
/**
* \brief Set the current endpoint type
*
* \param ssl SSL context
* \param endpoint must be SSL_IS_CLIENT or SSL_IS_SERVER
*/
void ssl_set_endpoint( ssl_context *ssl, int endpoint );
/**
* \brief Set the certificate verification mode
*
* \param ssl SSL context
* \param mode can be:
*
* SSL_VERIFY_NONE: peer certificate is not checked (default),
* this is insecure and SHOULD be avoided.
*
* SSL_VERIFY_OPTIONAL: peer certificate is checked, however the
* handshake continues even if verification failed;
* ssl_get_verify_result() can be called after the
* handshake is complete.
*
* SSL_VERIFY_REQUIRED: peer *must* present a valid certificate,
* handshake is aborted if verification failed.
*/
void ssl_set_authmode( ssl_context *ssl, int authmode );
/**
* \brief Set the random number generator callback
*
* \param ssl SSL context
* \param f_rng RNG function
* \param p_rng RNG parameter
*/
void ssl_set_rng( ssl_context *ssl,
int (*f_rng)(void *),
void *p_rng );
/**
* \brief Set the debug callback
*
* \param ssl SSL context
* \param f_dbg debug function
* \param p_dbg debug parameter
*/
void ssl_set_dbg( ssl_context *ssl,
void (*f_dbg)(void *, int, const char *),
void *p_dbg );
/**
* \brief Set the underlying BIO read and write callbacks
*
* \param ssl SSL context
* \param f_recv read callback
* \param p_recv read parameter
* \param f_send write callback
* \param p_send write parameter
*/
void ssl_set_bio( ssl_context *ssl,
int (*f_recv)(void *, unsigned char *, int), void *p_recv,
int (*f_send)(void *, unsigned char *, int), void *p_send );
/**
* \brief Set the session callbacks (server-side only)
*
* \param ssl SSL context
* \param s_get session get callback
* \param s_set session set callback
*/
void ssl_set_scb( ssl_context *ssl,
int (*s_get)(ssl_context *),
int (*s_set)(ssl_context *) );
/**
* \brief Set the session resuming flag, timeout and data
*
* \param ssl SSL context
* \param resume if 0 (default), the session will not be resumed
* \param timeout session timeout in seconds, or 0 (no timeout)
* \param session session context
*/
void ssl_set_session( ssl_context *ssl, int resume, int timeout,
ssl_session *session );
/**
* \brief Set the list of allowed ciphersuites
*
* \param ssl SSL context
* \param ciphers 0-terminated list of allowed ciphers
*/
void ssl_set_ciphers( ssl_context *ssl, int *ciphers );
/**
* \brief Set the data required to verify peer certificate
*
* \param ssl SSL context
* \param ca_chain trusted CA chain
* \param ca_crl trusted CA CRLs
* \param peer_cn expected peer CommonName (or NULL)
*
* \note TODO: add two more parameters: depth and crl
*/
void ssl_set_ca_chain( ssl_context *ssl, x509_cert *ca_chain,
x509_crl *ca_crl, const char *peer_cn );
/**
* \brief Set own certificate and private key
*
* \param ssl SSL context
* \param own_cert own public certificate
* \param rsa_key own private RSA key
*/
void ssl_set_own_cert( ssl_context *ssl, x509_cert *own_cert,
rsa_context *rsa_key );
/**
* \brief Set the Diffie-Hellman public P and G values,
* read as hexadecimal strings (server-side only)
*
* \param ssl SSL context
* \param dhm_P Diffie-Hellman-Merkle modulus
* \param dhm_G Diffie-Hellman-Merkle generator
*
* \return 0 if successful
*/
int ssl_set_dh_param( ssl_context *ssl, const char *dhm_P, const char *dhm_G );
/**
* \brief Set hostname for ServerName TLS Extension
*
*
* \param ssl SSL context
* \param hostname the server hostname
*
* \return 0 if successful
*/
int ssl_set_hostname( ssl_context *ssl, const char *hostname );
/**
* \brief Return the number of data bytes available to read
*
* \param ssl SSL context
*
* \return how many bytes are available in the read buffer
*/
int ssl_get_bytes_avail( const ssl_context *ssl );
/**
* \brief Return the result of the certificate verification
*
* \param ssl SSL context
*
* \return 0 if successful, or a combination of:
* BADCERT_EXPIRED
* BADCERT_REVOKED
* BADCERT_CN_MISMATCH
* BADCERT_NOT_TRUSTED
*/
int ssl_get_verify_result( const ssl_context *ssl );
/**
* \brief Return the name of the current cipher
*
* \param ssl SSL context
*
* \return a string containing the cipher name
*/
const char *ssl_get_cipher( const ssl_context *ssl );
/**
* \brief Perform the SSL handshake
*
* \param ssl SSL context
*
* \return 0 if successful, POLARSSL_ERR_NET_TRY_AGAIN,
* or a specific SSL error code.
*/
int ssl_handshake( ssl_context *ssl );
/**
* \brief Read at most 'len' application data bytes
*
* \param ssl SSL context
* \param buf buffer that will hold the data
* \param len how many bytes must be read
*
* \return This function returns the number of bytes read,
* or a negative error code.
*/
int ssl_read( ssl_context *ssl, unsigned char *buf, int len );
/**
* \brief Write exactly 'len' application data bytes
*
* \param ssl SSL context
* \param buf buffer holding the data
* \param len how many bytes must be written
*
* \return This function returns the number of bytes written,
* or a negative error code.
*
* \note When this function returns POLARSSL_ERR_NET_TRY_AGAIN,
* it must be called later with the *same* arguments,
* until it returns a positive value.
*/
int ssl_write( ssl_context *ssl, const unsigned char *buf, int len );
/**
* \brief Notify the peer that the connection is being closed
*
* \param ssl SSL context
*/
int ssl_close_notify( ssl_context *ssl );
/**
* \brief Free an SSL context
*
* \param ssl SSL context
*/
void ssl_free( ssl_context *ssl );
/*
* Internal functions (do not call directly)
*/
int ssl_handshake_client( ssl_context *ssl );
int ssl_handshake_server( ssl_context *ssl );
int ssl_derive_keys( ssl_context *ssl );
void ssl_calc_verify( ssl_context *ssl, unsigned char hash[36] );
int ssl_read_record( ssl_context *ssl );
int ssl_fetch_input( ssl_context *ssl, int nb_want );
int ssl_write_record( ssl_context *ssl );
int ssl_flush_output( ssl_context *ssl );
int ssl_parse_certificate( ssl_context *ssl );
int ssl_write_certificate( ssl_context *ssl );
int ssl_parse_change_cipher_spec( ssl_context *ssl );
int ssl_write_change_cipher_spec( ssl_context *ssl );
int ssl_parse_finished( ssl_context *ssl );
int ssl_write_finished( ssl_context *ssl );
#ifdef __cplusplus
}
#endif
#endif /* ssl.h */
library/ssl_cli.c
/*
* SSLv3/TLSv1 client-side functions
*
* Copyright (C) 2006-2010, Brainspark B.V.
*
* This file is part of PolarSSL (http://www.polarssl.org)
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
*
* All rights reserved.
*
* 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.
*/
#include "polarssl/config.h"
#if defined(POLARSSL_SSL_CLI_C)
#include "polarssl/debug.h"
#include "polarssl/ssl.h"
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
static int ssl_write_client_hello( ssl_context *ssl )
{
int ret, i, n;
unsigned char *buf;
unsigned char *p;
time_t t;
SSL_DEBUG_MSG( 2, ( "=> write client hello" ) );
ssl->major_ver = SSL_MAJOR_VERSION_3;
ssl->minor_ver = SSL_MINOR_VERSION_0;
ssl->max_major_ver = SSL_MAJOR_VERSION_3;
ssl->max_minor_ver = SSL_MINOR_VERSION_2;
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 highest version supported
* 6 . 9 current UNIX time
* 10 . 37 random bytes
*/
buf = ssl->out_msg;
p = buf + 4;
*p++ = (unsigned char) ssl->max_major_ver;
*p++ = (unsigned char) ssl->max_minor_ver;
SSL_DEBUG_MSG( 3, ( "client hello, max version: [%d:%d]",
buf[4], buf[5] ) );
t = time( NULL );
*p++ = (unsigned char)( t >> 24 );
*p++ = (unsigned char)( t >> 16 );
*p++ = (unsigned char)( t >> 8 );
*p++ = (unsigned char)( t );
SSL_DEBUG_MSG( 3, ( "client hello, current time: %lu", t ) );
for( i = 28; i > 0; i-- )
*p++ = (unsigned char) ssl->f_rng( ssl->p_rng );
memcpy( ssl->randbytes, buf + 6, 32 );
SSL_DEBUG_BUF( 3, "client hello, random bytes", buf + 6, 32 );
/*
* 38 . 38 session id length
* 39 . 39+n session id
* 40+n . 41+n cipherlist length
* 42+n . .. cipherlist
* .. . .. compression alg. (0)
* .. . .. extensions (unused)
*/
n = ssl->session->length;
if( n < 16 || n > 32 || ssl->resume == 0 ||
( ssl->timeout != 0 && t - ssl->session->start > ssl->timeout ) )
n = 0;
*p++ = (unsigned char) n;
for( i = 0; i < n; i++ )
*p++ = ssl->session->id[i];
SSL_DEBUG_MSG( 3, ( "client hello, session id len.: %d", n ) );
SSL_DEBUG_BUF( 3, "client hello, session id", buf + 39, n );
for( n = 0; ssl->ciphers[n] != 0; n++ );
*p++ = (unsigned char)( n >> 7 );
*p++ = (unsigned char)( n << 1 );
SSL_DEBUG_MSG( 3, ( "client hello, got %d ciphers", n ) );
for( i = 0; i < n; i++ )
{
SSL_DEBUG_MSG( 3, ( "client hello, add cipher: %2d",
ssl->ciphers[i] ) );
*p++ = (unsigned char)( ssl->ciphers[i] >> 8 );
*p++ = (unsigned char)( ssl->ciphers[i] );
}
SSL_DEBUG_MSG( 3, ( "client hello, compress len.: %d", 1 ) );
SSL_DEBUG_MSG( 3, ( "client hello, compress alg.: %d", 0 ) );
*p++ = 1;
*p++ = SSL_COMPRESS_NULL;
if ( ssl->hostname != NULL )
{
SSL_DEBUG_MSG( 3, ( "client hello, server name extension: %s",
ssl->hostname ) );
*p++ = (unsigned char)( ( (ssl->hostname_len + 9) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( (ssl->hostname_len + 9) ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_SERVERNAME >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_SERVERNAME ) & 0xFF );
*p++ = (unsigned char)( ( (ssl->hostname_len + 5) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( (ssl->hostname_len + 5) ) & 0xFF );
*p++ = (unsigned char)( ( (ssl->hostname_len + 3) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( (ssl->hostname_len + 3) ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_SERVERNAME_HOSTNAME ) & 0xFF );
*p++ = (unsigned char)( ( ssl->hostname_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->hostname_len ) & 0xFF );
memcpy( p, ssl->hostname, ssl->hostname_len );
p += ssl->hostname_len;
}
ssl->out_msglen = p - buf;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = SSL_HS_CLIENT_HELLO;
ssl->state++;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write client hello" ) );
return( 0 );
}
static int ssl_parse_server_hello( ssl_context *ssl )
{
time_t t;
int ret, i, n;
int ext_len;
unsigned char *buf;
SSL_DEBUG_MSG( 2, ( "=> parse server hello" ) );
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 protocol version
* 6 . 9 UNIX time()
* 10 . 37 random bytes
*/
buf = ssl->in_msg;
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
SSL_DEBUG_MSG( 3, ( "server hello, chosen version: [%d:%d]",
buf[4], buf[5] ) );
if( ssl->in_hslen < 42 ||
buf[0] != SSL_HS_SERVER_HELLO ||
buf[4] != SSL_MAJOR_VERSION_3 )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
if( buf[5] > ssl->max_minor_ver )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
ssl->minor_ver = buf[5];
t = ( (time_t) buf[6] << 24 )
| ( (time_t) buf[7] << 16 )
| ( (time_t) buf[8] << 8 )
| ( (time_t) buf[9] );
memcpy( ssl->randbytes + 32, buf + 6, 32 );
n = buf[38];
SSL_DEBUG_MSG( 3, ( "server hello, current time: %lu", t ) );
SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 6, 32 );
/*
* 38 . 38 session id length
* 39 . 38+n session id
* 39+n . 40+n chosen cipher
* 41+n . 41+n chosen compression alg.
* 42+n . 43+n extensions length
* 44+n . 44+n+m extensions
*/
if( n < 0 || n > 32 || ssl->in_hslen > 42 + n )
{
ext_len = ( ( buf[42 + n] << 8 )
| ( buf[43 + n] ) ) + 2;
}
else
{
ext_len = 0;
}
if( n < 0 || n > 32 || ssl->in_hslen != 42 + n + ext_len )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
i = ( buf[39 + n] << 8 ) | buf[40 + n];
SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) );
SSL_DEBUG_BUF( 3, "server hello, session id", buf + 39, n );
/*
* Check if the session can be resumed
*/
if( ssl->resume == 0 || n == 0 ||
ssl->session->cipher != i ||
ssl->session->length != n ||
memcmp( ssl->session->id, buf + 39, n ) != 0 )
{
ssl->state++;
ssl->resume = 0;
ssl->session->start = time( NULL );
ssl->session->cipher = i;
ssl->session->length = n;
memcpy( ssl->session->id, buf + 39, n );
}
else
{
ssl->state = SSL_SERVER_CHANGE_CIPHER_SPEC;
if( ( ret = ssl_derive_keys( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_derive_keys", ret );
return( ret );
}
}
SSL_DEBUG_MSG( 3, ( "%s session has been resumed",
ssl->resume ? "a" : "no" ) );
SSL_DEBUG_MSG( 3, ( "server hello, chosen cipher: %d", i ) );
SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d", buf[41 + n] ) );
i = 0;
while( 1 )
{
if( ssl->ciphers[i] == 0 )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
if( ssl->ciphers[i++] == ssl->session->cipher )
break;
}
if( buf[41 + n] != SSL_COMPRESS_NULL )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
/* TODO: Process extensions */
SSL_DEBUG_MSG( 2, ( "<= parse server hello" ) );
return( 0 );
}
static int ssl_parse_server_key_exchange( ssl_context *ssl )
{
int ret, n;
unsigned char *p, *end;
unsigned char hash[36];
md5_context md5;
sha1_context sha1;
SSL_DEBUG_MSG( 2, ( "=> parse server key exchange" ) );
if( ssl->session->cipher != SSL_EDH_RSA_DES_168_SHA &&
ssl->session->cipher != SSL_EDH_RSA_AES_128_SHA &&
ssl->session->cipher != SSL_EDH_RSA_AES_256_SHA &&
ssl->session->cipher != SSL_EDH_RSA_CAMELLIA_128_SHA &&
ssl->session->cipher != SSL_EDH_RSA_CAMELLIA_256_SHA)
{
SSL_DEBUG_MSG( 2, ( "<= skip parse server key exchange" ) );
ssl->state++;
return( 0 );
}
#if !defined(POLARSSL_DHM_C)
SSL_DEBUG_MSG( 1, ( "support for dhm in not available" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
#else
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
if( ssl->in_msg[0] != SSL_HS_SERVER_KEY_EXCHANGE )
{
SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
/*
* Ephemeral DH parameters:
*
* struct {
* opaque dh_p<1..2^16-1>;
* opaque dh_g<1..2^16-1>;
* opaque dh_Ys<1..2^16-1>;
* } ServerDHParams;
*/
p = ssl->in_msg + 4;
end = ssl->in_msg + ssl->in_hslen;
if( ( ret = dhm_read_params( &ssl->dhm_ctx, &p, end ) ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
if( (int)( end - p ) != ssl->peer_cert->rsa.len )
{
SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
if( ssl->dhm_ctx.len < 64 || ssl->dhm_ctx.len > 256 )
{
SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
SSL_DEBUG_MPI( 3, "DHM: P ", &ssl->dhm_ctx.P );
SSL_DEBUG_MPI( 3, "DHM: G ", &ssl->dhm_ctx.G );
SSL_DEBUG_MPI( 3, "DHM: GY", &ssl->dhm_ctx.GY );
/*
* digitally-signed struct {
* opaque md5_hash[16];
* opaque sha_hash[20];
* };
*
* md5_hash
* MD5(ClientHello.random + ServerHello.random
* + ServerParams);
* sha_hash
* SHA(ClientHello.random + ServerHello.random
* + ServerParams);
*/
n = ssl->in_hslen - ( end - p ) - 6;
md5_starts( &md5 );
md5_update( &md5, ssl->randbytes, 64 );
md5_update( &md5, ssl->in_msg + 4, n );
md5_finish( &md5, hash );
sha1_starts( &sha1 );
sha1_update( &sha1, ssl->randbytes, 64 );
sha1_update( &sha1, ssl->in_msg + 4, n );
sha1_finish( &sha1, hash + 16 );
SSL_DEBUG_BUF( 3, "parameters hash", hash, 36 );
if( ( ret = rsa_pkcs1_verify( &ssl->peer_cert->rsa, RSA_PUBLIC,
SIG_RSA_RAW, 36, hash, p ) ) != 0 )
{
SSL_DEBUG_RET( 1, "rsa_pkcs1_verify", ret );
return( ret );
}
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse server key exchange" ) );
return( 0 );
#endif
}
static int ssl_parse_certificate_request( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> parse certificate request" ) );
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 SSL version
* 6 . 6 cert type count
* 7 .. n-1 cert types
* n .. n+1 length of all DNs
* n+2 .. n+3 length of DN 1
* n+4 .. ... Distinguished Name #1
* ... .. ... length of DN 2, etc.
*/
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
ssl->client_auth = 0;
ssl->state++;
if( ssl->in_msg[0] == SSL_HS_CERTIFICATE_REQUEST )
ssl->client_auth++;
SSL_DEBUG_MSG( 3, ( "got %s certificate request",
ssl->client_auth ? "a" : "no" ) );
SSL_DEBUG_MSG( 2, ( "<= parse certificate request" ) );
return( 0 );
}
static int ssl_parse_server_hello_done( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> parse server hello done" ) );
if( ssl->client_auth != 0 )
{
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "bad server hello done message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
}
if( ssl->in_hslen != 4 ||
ssl->in_msg[0] != SSL_HS_SERVER_HELLO_DONE )
{
SSL_DEBUG_MSG( 1, ( "bad server hello done message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO_DONE );
}
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse server hello done" ) );
return( 0 );
}
static int ssl_write_client_key_exchange( ssl_context *ssl )
{
int ret, i, n;
SSL_DEBUG_MSG( 2, ( "=> write client key exchange" ) );
if( ssl->session->cipher == SSL_EDH_RSA_DES_168_SHA ||
ssl->session->cipher == SSL_EDH_RSA_AES_128_SHA ||
ssl->session->cipher == SSL_EDH_RSA_AES_256_SHA ||
ssl->session->cipher == SSL_EDH_RSA_CAMELLIA_128_SHA ||
ssl->session->cipher == SSL_EDH_RSA_CAMELLIA_256_SHA)
{
#if !defined(POLARSSL_DHM_C)
SSL_DEBUG_MSG( 1, ( "support for dhm in not available" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
#else
/*
* DHM key exchange -- send G^X mod P
*/
n = ssl->dhm_ctx.len;
ssl->out_msg[4] = (unsigned char)( n >> 8 );
ssl->out_msg[5] = (unsigned char)( n );
i = 6;
ret = dhm_make_public( &ssl->dhm_ctx, 256,
&ssl->out_msg[i], n,
ssl->f_rng, ssl->p_rng );
if( ret != 0 )
{
SSL_DEBUG_RET( 1, "dhm_make_public", ret );
return( ret );
}
SSL_DEBUG_MPI( 3, "DHM: X ", &ssl->dhm_ctx.X );
SSL_DEBUG_MPI( 3, "DHM: GX", &ssl->dhm_ctx.GX );
ssl->pmslen = ssl->dhm_ctx.len;
if( ( ret = dhm_calc_secret( &ssl->dhm_ctx,
ssl->premaster,
&ssl->pmslen ) ) != 0 )
{
SSL_DEBUG_RET( 1, "dhm_calc_secret", ret );
return( ret );
}
SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->dhm_ctx.K );
#endif
}
else
{
/*
* RSA key exchange -- send rsa_public(pkcs1 v1.5(premaster))
*/
ssl->premaster[0] = (unsigned char) ssl->max_major_ver;
ssl->premaster[1] = (unsigned char) ssl->max_minor_ver;
ssl->pmslen = 48;
for( i = 2; i < ssl->pmslen; i++ )
ssl->premaster[i] = (unsigned char) ssl->f_rng( ssl->p_rng );
i = 4;
n = ssl->peer_cert->rsa.len;
if( ssl->minor_ver != SSL_MINOR_VERSION_0 )
{
i += 2;
ssl->out_msg[4] = (unsigned char)( n >> 8 );
ssl->out_msg[5] = (unsigned char)( n );
}
ret = rsa_pkcs1_encrypt( &ssl->peer_cert->rsa,
ssl->f_rng, ssl->p_rng,
RSA_PUBLIC,
ssl->pmslen, ssl->premaster,
ssl->out_msg + i );
if( ret != 0 )
{
SSL_DEBUG_RET( 1, "rsa_pkcs1_encrypt", ret );
return( ret );
}
}
if( ( ret = ssl_derive_keys( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_derive_keys", ret );
return( ret );
}
ssl->out_msglen = i + n;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = SSL_HS_CLIENT_KEY_EXCHANGE;
ssl->state++;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write client key exchange" ) );
return( 0 );
}
static int ssl_write_certificate_verify( ssl_context *ssl )
{
int ret, n;
unsigned char hash[36];
SSL_DEBUG_MSG( 2, ( "=> write certificate verify" ) );
if( ssl->client_auth == 0 )
{
SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) );
ssl->state++;
return( 0 );
}
if( ssl->rsa_key == NULL )
{
SSL_DEBUG_MSG( 1, ( "got no private key" ) );
return( POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED );
}
/*
* Make an RSA signature of the handshake digests
*/
ssl_calc_verify( ssl, hash );
n = ssl->rsa_key->len;
ssl->out_msg[4] = (unsigned char)( n >> 8 );
ssl->out_msg[5] = (unsigned char)( n );
if( ( ret = rsa_pkcs1_sign( ssl->rsa_key, RSA_PRIVATE, SIG_RSA_RAW,
36, hash, ssl->out_msg + 6 ) ) != 0 )
{
SSL_DEBUG_RET( 1, "rsa_pkcs1_sign", ret );
return( ret );
}
ssl->out_msglen = 6 + n;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = SSL_HS_CERTIFICATE_VERIFY;
ssl->state++;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write certificate verify" ) );
return( 0 );
}
/*
* SSL handshake -- client side
*/
int ssl_handshake_client( ssl_context *ssl )
{
int ret = 0;
SSL_DEBUG_MSG( 2, ( "=> handshake client" ) );
while( ssl->state != SSL_HANDSHAKE_OVER )
{
SSL_DEBUG_MSG( 2, ( "client state: %d", ssl->state ) );
if( ( ret = ssl_flush_output( ssl ) ) != 0 )
break;
switch( ssl->state )
{
case SSL_HELLO_REQUEST:
ssl->state = SSL_CLIENT_HELLO;
break;
/*
* ==> ClientHello
*/
case SSL_CLIENT_HELLO:
ret = ssl_write_client_hello( ssl );
break;
/*
* <== ServerHello
* Certificate
* ( ServerKeyExchange )
* ( CertificateRequest )
* ServerHelloDone
*/
case SSL_SERVER_HELLO:
ret = ssl_parse_server_hello( ssl );
break;
case SSL_SERVER_CERTIFICATE:
ret = ssl_parse_certificate( ssl );
break;
case SSL_SERVER_KEY_EXCHANGE:
ret = ssl_parse_server_key_exchange( ssl );
break;
case SSL_CERTIFICATE_REQUEST:
ret = ssl_parse_certificate_request( ssl );
break;
case SSL_SERVER_HELLO_DONE:
ret = ssl_parse_server_hello_done( ssl );
break;
/*
* ==> ( Certificate/Alert )
* ClientKeyExchange
* ( CertificateVerify )
* ChangeCipherSpec
* Finished
*/
case SSL_CLIENT_CERTIFICATE:
ret = ssl_write_certificate( ssl );
break;
case SSL_CLIENT_KEY_EXCHANGE:
ret = ssl_write_client_key_exchange( ssl );
break;
case SSL_CERTIFICATE_VERIFY:
ret = ssl_write_certificate_verify( ssl );
break;
case SSL_CLIENT_CHANGE_CIPHER_SPEC:
ret = ssl_write_change_cipher_spec( ssl );
break;
case SSL_CLIENT_FINISHED:
ret = ssl_write_finished( ssl );
break;
/*
* <== ChangeCipherSpec
* Finished
*/
case SSL_SERVER_CHANGE_CIPHER_SPEC:
ret = ssl_parse_change_cipher_spec( ssl );
break;
case SSL_SERVER_FINISHED:
ret = ssl_parse_finished( ssl );
break;
case SSL_FLUSH_BUFFERS:
SSL_DEBUG_MSG( 2, ( "handshake: done" ) );
ssl->state = SSL_HANDSHAKE_OVER;
break;
default:
SSL_DEBUG_MSG( 1, ( "invalid state %d", ssl->state ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
if( ret != 0 )
break;
}
SSL_DEBUG_MSG( 2, ( "<= handshake client" ) );
return( ret );
}
#endif