From 3aed1851b384cc09355fe1f5218a5246f84e3e3a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= Date: Wed, 12 Aug 2015 14:53:56 +0200 Subject: [PATCH] Re-order functions. Use the same order for all read-write pair of functions --- library/ecjpake.c | 118 +++++++++++++++++++++++----------------------- 1 file changed, 59 insertions(+), 59 deletions(-) diff --git a/library/ecjpake.c b/library/ecjpake.c index f56142cc9..a61c146eb 100644 --- a/library/ecjpake.c +++ b/library/ecjpake.c @@ -118,65 +118,6 @@ cleanup: return( ret ); } -/* - * Generate ZKP (7.4.2.3.2) and write it as ECSchnorrZKP (7.4.2.2.2) - */ -static int ecjpake_zkp_write( const mbedtls_md_info_t *md_info, - const mbedtls_ecp_group *grp, - const mbedtls_ecp_point *G, - const mbedtls_mpi *x, - const mbedtls_ecp_point *X, - const char *id, - unsigned char **p, - const unsigned char *end, - int (*f_rng)(void *, unsigned char *, size_t), - void *p_rng ) -{ - int ret; - mbedtls_ecp_point V; - mbedtls_mpi v; - mbedtls_mpi h; /* later recycled to hold r */ - size_t len; - - if( end < *p ) - return( MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL ); - - mbedtls_ecp_point_init( &V ); - mbedtls_mpi_init( &v ); - mbedtls_mpi_init( &h ); - - /* Compute signature */ - MBEDTLS_MPI_CHK( mbedtls_ecp_gen_keypair_base( (mbedtls_ecp_group *) grp, - G, &v, &V, f_rng, p_rng ) ); - MBEDTLS_MPI_CHK( ecjpake_hash( md_info, grp, G, &V, X, id, &h ) ); - MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &h, &h, x ) ); /* x*h */ - MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &h, &v, &h ) ); /* v - x*h */ - MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &h, &h, &grp->N ) ); /* r */ - - /* Write it out */ - MBEDTLS_MPI_CHK( mbedtls_ecp_tls_write_point( grp, &V, - MBEDTLS_ECP_PF_UNCOMPRESSED, &len, *p, end - *p ) ); - *p += len; - - len = mbedtls_mpi_size( &h ); /* actually r */ - if( end < *p || (size_t)( end - *p ) < 1 + len || len > 255 ) - { - ret = MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL; - goto cleanup; - } - - *(*p)++ = (unsigned char)( len & 0xFF ); - MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &h, *p, len ) ); /* r */ - *p += len; - -cleanup: - mbedtls_ecp_point_free( &V ); - mbedtls_mpi_free( &v ); - mbedtls_mpi_free( &h ); - - return( ret ); -} - /* * Parse a ECShnorrZKP (7.4.2.2.2) and verify it (7.4.2.3.3) */ @@ -248,6 +189,65 @@ cleanup: return( ret ); } +/* + * Generate ZKP (7.4.2.3.2) and write it as ECSchnorrZKP (7.4.2.2.2) + */ +static int ecjpake_zkp_write( const mbedtls_md_info_t *md_info, + const mbedtls_ecp_group *grp, + const mbedtls_ecp_point *G, + const mbedtls_mpi *x, + const mbedtls_ecp_point *X, + const char *id, + unsigned char **p, + const unsigned char *end, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng ) +{ + int ret; + mbedtls_ecp_point V; + mbedtls_mpi v; + mbedtls_mpi h; /* later recycled to hold r */ + size_t len; + + if( end < *p ) + return( MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL ); + + mbedtls_ecp_point_init( &V ); + mbedtls_mpi_init( &v ); + mbedtls_mpi_init( &h ); + + /* Compute signature */ + MBEDTLS_MPI_CHK( mbedtls_ecp_gen_keypair_base( (mbedtls_ecp_group *) grp, + G, &v, &V, f_rng, p_rng ) ); + MBEDTLS_MPI_CHK( ecjpake_hash( md_info, grp, G, &V, X, id, &h ) ); + MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &h, &h, x ) ); /* x*h */ + MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &h, &v, &h ) ); /* v - x*h */ + MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &h, &h, &grp->N ) ); /* r */ + + /* Write it out */ + MBEDTLS_MPI_CHK( mbedtls_ecp_tls_write_point( grp, &V, + MBEDTLS_ECP_PF_UNCOMPRESSED, &len, *p, end - *p ) ); + *p += len; + + len = mbedtls_mpi_size( &h ); /* actually r */ + if( end < *p || (size_t)( end - *p ) < 1 + len || len > 255 ) + { + ret = MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL; + goto cleanup; + } + + *(*p)++ = (unsigned char)( len & 0xFF ); + MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &h, *p, len ) ); /* r */ + *p += len; + +cleanup: + mbedtls_ecp_point_free( &V ); + mbedtls_mpi_free( &v ); + mbedtls_mpi_free( &h ); + + return( ret ); +} + /* * Parse a ECJPAKEKeyKP (7.4.2.2.1) and check proof * Output: verified public key X