Added ecp_read_binary().

This commit is contained in:
Manuel Pégourié-Gonnard 2012-11-24 16:19:42 +01:00 committed by Paul Bakker
parent 37d218a8e3
commit 5e402d88ea
4 changed files with 106 additions and 1 deletions

View file

@ -218,7 +218,7 @@ int ecp_group_read_string( ecp_group *grp, int radix,
/**
* \brief Export a point into unsigned binary data
*
* \param grp Group the point belongs to
* \param grp Group to which the point should belong
* \param P Point to export
* \param format Point format, should be a POLARSSL_ECP_PF_XXX macro
* \param olen Length of the actual ouput
@ -230,6 +230,25 @@ int ecp_group_read_string( ecp_group *grp, int radix,
int ecp_write_binary( const ecp_group *grp, const ecp_point *P, int format,
size_t *olen, unsigned char *buf, size_t buflen );
/**
* \brief Import a point from unsigned binary data
*
* \param grp Group to which the point should belong
* \param P Point to import
* \param format Point format, must be POLARSSL_ECP_PF_UNCOMPRESSED for now
* \param buf Input buffer
* \param ilen Actual length of input
*
* \return 0 if successful,
* POLARSSL_ERR_ECP_GENERIC if input is invalid
* POLARSSL_ERR_MPI_MALLOC_FAILED if memory allocation failed
*
* \note This function does NOT check that the point actually
* belongs to the given group, see ecp_check_pubkey() for
* that.
*/
int ecp_read_binary( const ecp_group *grp, ecp_point *P, int format,
const unsigned char *buf, size_t ilen );
/**
* \brief Set a group using well-known domain parameters
*

View file

@ -228,6 +228,33 @@ cleanup:
return( ret );
}
/*
* Import a point from unsigned binary data (SEC1 2.3.4)
*/
int ecp_read_binary( const ecp_group *grp, ecp_point *P, int format,
const unsigned char *buf, size_t ilen ) {
int ret;
size_t plen;
if( format != POLARSSL_ECP_PF_UNCOMPRESSED )
return( POLARSSL_ERR_ECP_GENERIC );
if( ilen == 1 && buf[0] == 0x00 )
return( ecp_set_zero( P ) );
plen = mpi_size( &grp-> P );
if( ilen != 2 * plen + 1 || buf[0] != 0x04 )
return( POLARSSL_ERR_ECP_GENERIC );
MPI_CHK( mpi_read_binary( &P->X, buf + 1, plen ) );
MPI_CHK( mpi_read_binary( &P->Y, buf + 1 + plen, plen ) );
MPI_CHK( mpi_lset( &P->Z, 1 ) );
cleanup:
return( ret );
}
/*
* Wrapper around fast quasi-modp functions, with fall-back to mpi_mod_mpi.
* See the documentation of struct ecp_group.

View file

@ -163,6 +163,27 @@ ecp_write_binary:SECP192R1:"48d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc9933":"6
ECP write binary #7 (odd, compressed, buffer just fits)
ecp_write_binary:SECP192R1:"48d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc9933":"93112b28345b7d1d7799611e49bea9d8290cb2d7afe1f9f3":"01":COMPRESSED:"0348d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc9933":25:0
ECP read binary #0 (invalid format)
ecp_read_binary:SECP192R1:"00":UNKNOWN:"01":"01":"00":POLARSSL_ERR_ECP_GENERIC
ECP read binary #1 (zero, invalid ilen)
ecp_read_binary:SECP192R1:"0000":UNCOMPRESSED:"01":"01":"00":POLARSSL_ERR_ECP_GENERIC
ECP read binary #2 (zero, invalid first byte)
ecp_read_binary:SECP192R1:"01":UNCOMPRESSED:"01":"01":"00":POLARSSL_ERR_ECP_GENERIC
ECP read binary #3 (zero, OK)
ecp_read_binary:SECP192R1:"00":UNCOMPRESSED:"01":"01":"00":0
ECP read binary #4 (non-zero, invalid ilen)
ecp_read_binary:SECP192R1:"04001122":UNCOMPRESSED:"01":"01":"00":POLARSSL_ERR_ECP_GENERIC
ECP read binary #5 (non-zero, invalid first byte)
ecp_read_binary:SECP192R1:"0548d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc99336ceed4d7cba482e288669ee1b6415626d6f34d28501e060c":UNCOMPRESSED:"48d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc9933":"6ceed4d7cba482e288669ee1b6415626d6f34d28501e060c":"01":POLARSSL_ERR_ECP_GENERIC
ECP read binary #6 (non-zero, OK)
ecp_read_binary:SECP192R1:"0448d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc99336ceed4d7cba482e288669ee1b6415626d6f34d28501e060c":UNCOMPRESSED:"48d8082a3a1e3112bc03a8ef2f6d40d0a77a6f8e00cc9933":"6ceed4d7cba482e288669ee1b6415626d6f34d28501e060c":"01":0
ECP mod p192 readable
ecp_fast_mod:SECP192R1:"000000000000010500000000000001040000000000000103000000000000010200000000000001010000000000000100"

View file

@ -257,6 +257,44 @@ ecp_write_binary:id:x:y:z:format:out:blen:ret
}
END_CASE
BEGIN_CASE
ecp_read_binary:id:input:format:x:y:z:ret
{
ecp_group grp;
ecp_point P;
mpi X, Y, Z;
int ilen;
unsigned char buf[256];
memset( buf, 0, sizeof( buf ) );
ecp_group_init( &grp ); ecp_point_init( &P );
mpi_init( &X ); mpi_init( &Y ); mpi_init( &Z );
TEST_ASSERT( ecp_use_known_dp( &grp, POLARSSL_ECP_DP_{id} ) == 0 );
TEST_ASSERT( mpi_read_string( &X, 16, {x} ) == 0 );
TEST_ASSERT( mpi_read_string( &Y, 16, {y} ) == 0 );
TEST_ASSERT( mpi_read_string( &Z, 16, {z} ) == 0 );
ilen = unhexify( buf, {input} );
#define POLARSSL_ECP_PF_UNKNOWN -1
TEST_ASSERT( ecp_read_binary( &grp, &P, POLARSSL_ECP_PF_{format},
buf, ilen ) == {ret} );
if( {ret} == 0 )
{
TEST_ASSERT( mpi_cmp_mpi( &P.X, &X ) == 0 );
TEST_ASSERT( mpi_cmp_mpi( &P.Y, &Y ) == 0 );
TEST_ASSERT( mpi_cmp_mpi( &P.Z, &Z ) == 0 );
}
ecp_group_free( &grp ); ecp_point_free( &P );
mpi_free( &X ); mpi_free( &Y ); mpi_free( &Z );
}
END_CASE
BEGIN_CASE
ecp_selftest:
{