eden-emu/mbedtls
15
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Generate random key for HelloVerifyRequest

Browse source
This commit is contained in:
Manuel Pégourié-Gonnard 2014-07-22 22:10:43 +02:00 • committed by Paul Bakker
parent dd3cdb0fbc
commit 98545f128a
4 changed files with 43 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

44
library/ssl_srv.c
View file

@ -1159,6 +1159,30 @@ have_ciphersuite_v2:
#error "DTLS hello verify needs SHA-1 or SHA-2"
#endif
/*
* Generate server key for HelloVerifyRequest
*/
int ssl_setup_hvr_key( ssl_context *ssl )
{
int ret;
unsigned char key[HVR_MD_LEN];
if( ( ret = ssl->f_rng( ssl->p_rng, key, sizeof( key ) ) ) != 0 )
return( ret );
ret = md_init_ctx( &ssl->hvr_hmac_ctx, md_info_from_type( HVR_MD ) );
if( ret != 0 )
return( ret );
ret = md_hmac_starts( &ssl->hvr_hmac_ctx, key, sizeof( key ) );
if( ret != 0 )
return( ret );
polarssl_zeroize( key, sizeof( key ) );
return( 0 );
}
/*
* Generate cookie for DTLS ClientHello verification
*/
@ -1168,10 +1192,6 @@ static int ssl_generate_verify_cookie( ssl_context *ssl )
unsigned char *cookie = ssl->handshake->verify_cookie;
unsigned char cookie_len;
unsigned char hmac_out[HVR_MD_LEN];
unsigned char hmac_key[32] = { 0 }; /* temporary! */
md_context_t hmac_ctx;
md_init( &hmac_ctx );
polarssl_free( cookie );
@ -1183,23 +1203,17 @@ static int ssl_generate_verify_cookie( ssl_context *ssl )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
/* Do a HMAC of client id */
ret = md_init_ctx( &hmac_ctx, md_info_from_type( HVR_MD ) );
if( ret != 0 )
if( ( ret = md_hmac_reset( &ssl->hvr_hmac_ctx ) ) != 0 ||
( ret = md_hmac_update( &ssl->hvr_hmac_ctx,
ssl->cli_id, ssl->cli_id_len ) ) != 0 ||
( ret = md_hmac_finish( &ssl->hvr_hmac_ctx, hmac_out ) ) != 0 )
{
SSL_DEBUG_RET( 0, "md_init_ctx", ret );
SSL_DEBUG_RET( 1, "md_hmac", ret );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
/* Only possible error is if hmac_ctx wasn't initialized */
(void) md_hmac_starts( &hmac_ctx, hmac_key, sizeof( hmac_key ) );
(void) md_hmac_update( &hmac_ctx, ssl->cli_id, ssl->cli_id_len );
(void) md_hmac_finish( &hmac_ctx, hmac_out );
memcpy( cookie, hmac_out, HVR_MD_USE );
md_free( &hmac_ctx );
ssl->handshake->verify_cookie = cookie;
ssl->handshake->verify_cookie_len = cookie_len;