Unify round two

This commit is contained in:
Manuel Pégourié-Gonnard 2015-08-14 14:20:48 +02:00
parent d8204a7bea
commit e1927101fb
2 changed files with 61 additions and 186 deletions

View File

@ -150,40 +150,6 @@ int mbedtls_ecjpake_read_round_one( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len );
/*
* \brief Generate and write ServerECJPAKEParams
* (the contents for the ServerKeyExchange)
*
* \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_params( 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 ServerECJPAKEParams
* (the contents for the ServerKeyExchange)
*
* \param ctx Context to use
* \param buf Pointer to the message
* \param len Message length
*
* \return 0 if successfull,
* a negative error code otherwise
*/
int mbedtls_ecjpake_tls_read_server_params( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len );
/*
* \brief Generate and write ClientECJPAKEParams
* (the contents for the ClientKeyExchange)
@ -198,7 +164,7 @@ int mbedtls_ecjpake_tls_read_server_params( mbedtls_ecjpake_context *ctx,
* \return 0 if successfull,
* a negative error code otherwise
*/
int mbedtls_ecjpake_tls_write_client_params( mbedtls_ecjpake_context *ctx,
int mbedtls_ecjpake_write_round_two( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng );
@ -214,7 +180,7 @@ int mbedtls_ecjpake_tls_write_client_params( mbedtls_ecjpake_context *ctx,
* \return 0 if successfull,
* a negative error code otherwise
*/
int mbedtls_ecjpake_tls_read_client_params( mbedtls_ecjpake_context *ctx,
int mbedtls_ecjpake_read_round_two( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len );

View File

@ -512,9 +512,9 @@ cleanup:
}
/*
* Read and process ServerECJPAKEParams (7.4.2.5)
* Read and process second round message (C: 7.4.2.5, S: 7.4.2.6)
*/
int mbedtls_ecjpake_tls_read_server_params( mbedtls_ecjpake_context *ctx,
int mbedtls_ecjpake_read_round_two( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len )
{
@ -522,28 +522,30 @@ int mbedtls_ecjpake_tls_read_server_params( mbedtls_ecjpake_context *ctx,
const unsigned char *p = buf;
const unsigned char *end = buf + len;
mbedtls_ecp_group grp;
mbedtls_ecp_point GB;
mbedtls_ecp_point G;
mbedtls_ecp_group_init( &grp );
mbedtls_ecp_point_init( &GB );
mbedtls_ecp_point_init( &G );
/*
* Server: GA = X3 + X4 + X1 (7.4.2.6.1)
* Client: GB = X1 + X2 + X3 (7.4.2.5.1)
* Unified: GB = Xm1 + Xm2 + Xp1
* Unified: G = Xm1 + Xm2 + Xp1
* We need that before parsing in order to check Xp as we read it
*/
MBEDTLS_MPI_CHK( ecjpake_ecp_add3( &ctx->grp, &GB,
MBEDTLS_MPI_CHK( ecjpake_ecp_add3( &ctx->grp, &G,
&ctx->Xm1, &ctx->Xm2, &ctx->Xp1 ) );
/*
* struct {
* ECParameters curve_params;
* ECParameters curve_params; // only client reading server msg
* ECJPAKEKeyKP ecjpake_key_kp;
* } ServerECJPAKEParams;
* } Client/ServerECJPAKEParams;
*/
if( ctx->role == MBEDTLS_ECJPAKE_CLIENT )
MBEDTLS_MPI_CHK( mbedtls_ecp_tls_read_group( &grp, &p, len ) );
MBEDTLS_MPI_CHK( ecjpake_kkp_read( ctx->md_info, &ctx->grp,
&GB, &ctx->Xp, ID_PEER, &p, end ) );
&G, &ctx->Xp, ID_PEER, &p, end ) );
if( p != end )
{
@ -552,185 +554,92 @@ int mbedtls_ecjpake_tls_read_server_params( mbedtls_ecjpake_context *ctx,
}
/*
* Xs already checked, only thing left to check is the group
* Xs already checked, only thing left to check is the group,
*/
if( grp.id != ctx->grp.id )
if( ctx->role == MBEDTLS_ECJPAKE_CLIENT && grp.id != ctx->grp.id )
{
ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
goto cleanup;
}
cleanup:
mbedtls_ecp_group_free( &grp );
mbedtls_ecp_point_free( &GB );
mbedtls_ecp_point_free( &G );
return( ret );
}
/*
* Generate and write ServerECJPAKEParams (7.4.2.5)
* Generate and write the second round message (S: 7.4.2.5, C: 7.4.2.6)
*/
int mbedtls_ecjpake_tls_write_server_params( mbedtls_ecjpake_context *ctx,
int mbedtls_ecjpake_write_round_two( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
mbedtls_ecp_point GB, Xs;
mbedtls_mpi xs;
mbedtls_ecp_point G; /* C: GA, S: GB */
mbedtls_ecp_point Xm; /* C: Xc, S: Xs */
mbedtls_mpi xm; /* C: xc, S: xs */
unsigned char *p = buf;
const unsigned char *end = buf + len;
size_t ec_len;
if( end < p )
return( MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL );
mbedtls_ecp_point_init( &GB );
mbedtls_ecp_point_init( &Xs );
mbedtls_mpi_init( &xs );
mbedtls_ecp_point_init( &G );
mbedtls_ecp_point_init( &Xm );
mbedtls_mpi_init( &xm );
/*
* First generate private/public key pair (7.4.2.5.1)
* First generate private/public key pair (S: 7.4.2.5.1, C: 7.4.2.6.1)
*
* Server: GB = X1 + X2 + X3
* Unified:
* xs = x4 * s mod n
* Xs = xs * GB
* Client: GA = X1 + X3 + X4 | xs = x2 * s | Xc = xc * GA
* Server: GB = X3 + X1 + X2 | xs = x4 * s | Xs = xs * GB
* Unified: G = Xm1 + Xp1 + Xp2 | xm = xm2 * s | Xm = xm * G
*/
MBEDTLS_MPI_CHK( ecjpake_ecp_add3( &ctx->grp, &GB,
MBEDTLS_MPI_CHK( ecjpake_ecp_add3( &ctx->grp, &G,
&ctx->Xp1, &ctx->Xp2, &ctx->Xm1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &xs, &ctx->xm2, &ctx->s ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &xs, &xs, &ctx->grp.N ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &ctx->grp, &Xs, &xs, &GB, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &xm, &ctx->xm2, &ctx->s ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &xm, &xm, &ctx->grp.N ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &ctx->grp, &Xm, &xm, &G, f_rng, p_rng ) );
/*
* Now write things out
*
* struct {
* ECParameters curve_params; // only server writing its message
* ECJPAKEKeyKP ecjpake_key_kp;
* } Client/ServerECJPAKEParams;
*/
if( ctx->role == MBEDTLS_ECJPAKE_SERVER )
{
if( end < p )
{
ret = MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL;
goto cleanup;
}
MBEDTLS_MPI_CHK( mbedtls_ecp_tls_write_group( &ctx->grp, &ec_len,
p, end - p ) );
p += ec_len;
}
if( end < p )
{
ret = MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL;
goto cleanup;
}
MBEDTLS_MPI_CHK( mbedtls_ecp_tls_write_point( &ctx->grp, &Xs,
MBEDTLS_MPI_CHK( mbedtls_ecp_tls_write_point( &ctx->grp, &Xm,
MBEDTLS_ECP_PF_UNCOMPRESSED, &ec_len, p, end - p ) );
p += ec_len;
MBEDTLS_MPI_CHK( ecjpake_zkp_write( ctx->md_info, &ctx->grp,
&GB, &xs, &Xs, ID_MINE,
&G, &xm, &Xm, ID_MINE,
&p, end, f_rng, p_rng ) );
*olen = p - buf;
cleanup:
mbedtls_ecp_point_free( &GB );
mbedtls_ecp_point_free( &Xs );
mbedtls_mpi_free( &xs );
return( ret );
}
/*
* Read and process ClientECJPAKEParams (7.4.2.6)
*/
int mbedtls_ecjpake_tls_read_client_params( mbedtls_ecjpake_context *ctx,
const unsigned char *buf,
size_t len )
{
int ret;
const unsigned char *p = buf;
const unsigned char *end = buf + len;
mbedtls_ecp_group grp;
mbedtls_ecp_point GA;
mbedtls_ecp_group_init( &grp );
mbedtls_ecp_point_init( &GA );
/*
* Server: GA = X1 + X3 + X4 (7.4.2.6.1)
* Unified: G = Xp1 + Xm1 + Xm2
* We need that before parsing in order to check Xc as we read it
*/
MBEDTLS_MPI_CHK( ecjpake_ecp_add3( &ctx->grp, &GA,
&ctx->Xp1, &ctx->Xm1, &ctx->Xm2 ) );
/*
* struct {
* ECJPAKEKeyKP ecjpake_key_kp;
* } CLientECJPAKEParams;
*/
MBEDTLS_MPI_CHK( ecjpake_kkp_read( ctx->md_info, &ctx->grp,
&GA, &ctx->Xp, ID_PEER, &p, end ) );
if( p != end )
{
ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
goto cleanup;
}
cleanup:
mbedtls_ecp_group_free( &grp );
mbedtls_ecp_point_free( &GA );
return( ret );
}
/*
* Generate and write ClientECJPAKEParams (7.4.2.6)
*/
int mbedtls_ecjpake_tls_write_client_params( mbedtls_ecjpake_context *ctx,
unsigned char *buf, size_t len, size_t *olen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
mbedtls_ecp_point GA, Xc;
mbedtls_mpi xc;
unsigned char *p = buf;
const unsigned char *end = buf + len;
size_t ec_len;
if( end < p )
return( MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL );
mbedtls_ecp_point_init( &GA );
mbedtls_ecp_point_init( &Xc );
mbedtls_mpi_init( &xc );
/*
* First generate private/public key pair (7.4.2.6.1)
*
* Client: GA = X1 + X3 + X4
* Unified: G = Xm1 + Xp1 + Xp2
* xc = x2 * s mod n
* Xc = xc * GA
*/
MBEDTLS_MPI_CHK( ecjpake_ecp_add3( &ctx->grp, &GA,
&ctx->Xm1, &ctx->Xp1, &ctx->Xp2 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &xc, &ctx->xm2, &ctx->s ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &xc, &xc, &ctx->grp.N ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_mul( &ctx->grp, &Xc, &xc, &GA, f_rng, p_rng ) );
/*
* Now write things out
*/
MBEDTLS_MPI_CHK( mbedtls_ecp_tls_write_point( &ctx->grp, &Xc,
MBEDTLS_ECP_PF_UNCOMPRESSED, &ec_len, p, end - p ) );
p += ec_len;
MBEDTLS_MPI_CHK( ecjpake_zkp_write( ctx->md_info, &ctx->grp,
&GA, &xc, &Xc, ID_MINE,
&p, end, f_rng, p_rng ) );
*olen = p - buf;
cleanup:
mbedtls_ecp_point_free( &GA );
mbedtls_ecp_point_free( &Xc );
mbedtls_mpi_free( &xc );
mbedtls_ecp_point_free( &G );
mbedtls_ecp_point_free( &Xm );
mbedtls_mpi_free( &xm );
return( ret );
}
@ -1032,18 +941,18 @@ int mbedtls_ecjpake_self_test( int verbose )
TEST_ASSERT( mbedtls_ecjpake_read_round_one( &cli, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_write_server_params( &srv,
TEST_ASSERT( mbedtls_ecjpake_write_round_two( &srv,
buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_read_server_params( &cli, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_read_round_two( &cli, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_derive_pms( &cli,
pms, sizeof( pms ), &pmslen, ecjpake_lgc, NULL ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_write_client_params( &cli,
TEST_ASSERT( mbedtls_ecjpake_write_round_two( &cli,
buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_read_client_params( &srv, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_read_round_two( &srv, buf, len ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_derive_pms( &srv,
buf, sizeof( buf ), &len, ecjpake_lgc, NULL ) == 0 );
@ -1077,12 +986,12 @@ int mbedtls_ecjpake_self_test( int verbose )
ecjpake_test_srv_ext,
sizeof( ecjpake_test_srv_ext ) ) == 0 );
TEST_ASSERT( mbedtls_ecjpake_tls_read_server_params( &cli,
TEST_ASSERT( mbedtls_ecjpake_read_round_two( &cli,
ecjpake_test_srv_kx,
sizeof( ecjpake_test_srv_kx ) ) == 0 );
/* Server reads client key exchange */
TEST_ASSERT( mbedtls_ecjpake_tls_read_client_params( &srv,
TEST_ASSERT( mbedtls_ecjpake_read_round_two( &srv,
ecjpake_test_cli_kx,
sizeof( ecjpake_test_cli_kx ) ) == 0 );