Provide symmetric API for the first round

This commit is contained in:
Manuel Pégourié-Gonnard 2015-08-14 13:36:55 +02:00
parent e2d3a4e1b4
commit d8204a7bea
2 changed files with 32 additions and 80 deletions

View file

@ -27,8 +27,17 @@
* Implementation based on Chapter 7.4 of the Thread v1.0 Specification, * Implementation based on Chapter 7.4 of the Thread v1.0 Specification,
* available from the Thread Group http://threadgroup.org/ * available from the Thread Group http://threadgroup.org/
* *
* This file implements the EC J-PAKE algorithm, with payload serializations * J-PAKE is a password-authenticated key exchange that allows deriving a
* strong shared secret from a (potentially low entropy) pre-shared
* passphrase, with forward secrecy and mutual authentication.
* https://en.wikipedia.org/wiki/Password_Authenticated_Key_Exchange_by_Juggling
*
* This file implements the EC J-PAKE algorithm with payload serializations
* suitable for use in TLS, but the result could be used outside TLS. * suitable for use in TLS, but the result could be used outside TLS.
*
* As the J-PAKE algorithm is inherently symmetric, so is our API.
* Each party needs to send its first round message, in any order, to the
* other party, then each sends its second round message, in any order.
*/ */
#include "ecp.h" #include "ecp.h"
@ -107,8 +116,9 @@ int mbedtls_ecjpake_setup( mbedtls_ecjpake_context *ctx,
size_t len ); size_t len );
/* /*
* \brief Generate and write contents of ClientHello extension * \brief Generate and write the first round message
* (excluding extension type and length bytes) * (TLS: contents of the Client/ServerHello extension,
* excluding extension type and length bytes)
* *
* \param ctx Context to use * \param ctx Context to use
* \param buf Buffer to write the contents to * \param buf Buffer to write the contents to
@ -120,13 +130,14 @@ int mbedtls_ecjpake_setup( mbedtls_ecjpake_context *ctx,
* \return 0 if successfull, * \return 0 if successfull,
* a negative error code otherwise * a negative error code otherwise
*/ */
int mbedtls_ecjpake_tls_write_client_ext( mbedtls_ecjpake_context *ctx, int mbedtls_ecjpake_write_round_one( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen, unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t), int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng ); void *p_rng );
/* /*
* \brief Read and process contents of the ClientHello extension * \brief Generate and write the first round message
* (excluding extension type and length bytes) * (TLS: contents of the Client/ServerHello extension,
* excluding extension type and length bytes)
* *
* \param ctx Context to use * \param ctx Context to use
* \param buf Pointer to extension contents * \param buf Pointer to extension contents
@ -135,43 +146,9 @@ int mbedtls_ecjpake_tls_write_client_ext( mbedtls_ecjpake_context *ctx,
* \return 0 if successfull, * \return 0 if successfull,
* a negative error code otherwise * a negative error code otherwise
*/ */
int mbedtls_ecjpake_tls_read_client_ext( mbedtls_ecjpake_context *ctx, int mbedtls_ecjpake_read_round_one( mbedtls_ecjpake_context *ctx,
const unsigned char *buf, const unsigned char *buf,
size_t len ); size_t len );
/*
* \brief Generate and write contents of ServerHello extension
* (excluding extension type and length bytes)
*
* \param ctx Context to use
* \param buf Buffer to write the contents to
* \param len Buffer size
* \param olen Will be updated with the number of bytes written
* \param f_rng RNG function
* \param p_rng RNG parameter
*
* \return 0 if successfull,
* a negative error code otherwise
*/
int mbedtls_ecjpake_tls_write_server_ext( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng );
/*
* \brief Read and process contents of the ServerHello extension
* (excluding extension type and length bytes)
*
* \param ctx Context to use
* \param buf Pointer to extension contents
* \param len Extension length
*
* \return 0 if successfull,
* a negative error code otherwise
*/
int mbedtls_ecjpake_tls_read_server_ext( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len );
/* /*
* \brief Generate and write ServerECJPAKEParams * \brief Generate and write ServerECJPAKEParams

View file

@ -464,11 +464,11 @@ cleanup:
} }
/* /*
* Read the contents of the ClientHello extension * Read and process the first round message
*/ */
int mbedtls_ecjpake_tls_read_client_ext( mbedtls_ecjpake_context *ctx, int mbedtls_ecjpake_read_round_one( mbedtls_ecjpake_context *ctx,
const unsigned char *buf, const unsigned char *buf,
size_t len ) size_t len )
{ {
return( ecjpake_kkpp_read( ctx->md_info, &ctx->grp, &ctx->grp.G, return( ecjpake_kkpp_read( ctx->md_info, &ctx->grp, &ctx->grp.G,
&ctx->Xp1, &ctx->Xp2, ID_PEER, &ctx->Xp1, &ctx->Xp2, ID_PEER,
@ -476,34 +476,9 @@ int mbedtls_ecjpake_tls_read_client_ext( mbedtls_ecjpake_context *ctx,
} }
/* /*
* Read the contents of the ServerHello extension * Generate and write the first round message
*/ */
int mbedtls_ecjpake_tls_read_server_ext( mbedtls_ecjpake_context *ctx, int mbedtls_ecjpake_write_round_one( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len )
{
return( ecjpake_kkpp_read( ctx->md_info, &ctx->grp, &ctx->grp.G,
&ctx->Xp1, &ctx->Xp2, ID_PEER,
buf, len ) );
}
/*
* Generate the contents of the ClientHello extension
*/
int mbedtls_ecjpake_tls_write_client_ext( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
return( ecjpake_kkpp_write( ctx->md_info, &ctx->grp, &ctx->grp.G,
&ctx->xm1, &ctx->Xm1, &ctx->xm2, &ctx->Xm2,
ID_MINE, buf, len, olen, f_rng, p_rng ) );
}
/*
* Generate the contents of the ServerHello extension
*/
int mbedtls_ecjpake_tls_write_server_ext( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen, unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t), int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng ) void *p_rng )
@ -1047,15 +1022,15 @@ int mbedtls_ecjpake_self_test( int verbose )
if( verbose != 0 ) if( verbose != 0 )
mbedtls_printf( " ECJPAKE test #1 (random handshake): " ); mbedtls_printf( " ECJPAKE test #1 (random handshake): " );
TEST_ASSERT( mbedtls_ecjpake_tls_write_client_ext( &cli, TEST_ASSERT( mbedtls_ecjpake_write_round_one( &cli,
buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 ); buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_read_client_ext( &srv, buf, len ) == 0 ); TEST_ASSERT( mbedtls_ecjpake_read_round_one( &srv, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_write_server_ext( &srv, TEST_ASSERT( mbedtls_ecjpake_write_round_one( &srv,
buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 ); buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_read_server_ext( &cli, buf, len ) == 0 ); TEST_ASSERT( mbedtls_ecjpake_read_round_one( &cli, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_write_server_params( &srv, TEST_ASSERT( mbedtls_ecjpake_tls_write_server_params( &srv,
buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 ); buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 );
@ -1088,7 +1063,7 @@ int mbedtls_ecjpake_self_test( int verbose )
ecjpake_test_x2, sizeof( ecjpake_test_x2 ) ) ); ecjpake_test_x2, sizeof( ecjpake_test_x2 ) ) );
/* Server reads client ext */ /* Server reads client ext */
TEST_ASSERT( mbedtls_ecjpake_tls_read_client_ext( &srv, TEST_ASSERT( mbedtls_ecjpake_read_round_one( &srv,
ecjpake_test_cli_ext, ecjpake_test_cli_ext,
sizeof( ecjpake_test_cli_ext ) ) == 0 ); sizeof( ecjpake_test_cli_ext ) ) == 0 );
@ -1098,7 +1073,7 @@ int mbedtls_ecjpake_self_test( int verbose )
ecjpake_test_x4, sizeof( ecjpake_test_x4 ) ) ); ecjpake_test_x4, sizeof( ecjpake_test_x4 ) ) );
/* Client reads server ext and key exchange */ /* Client reads server ext and key exchange */
TEST_ASSERT( mbedtls_ecjpake_tls_read_server_ext( &cli, TEST_ASSERT( mbedtls_ecjpake_read_round_one( &cli,
ecjpake_test_srv_ext, ecjpake_test_srv_ext,
sizeof( ecjpake_test_srv_ext ) ) == 0 ); sizeof( ecjpake_test_srv_ext ) ) == 0 );