1 /*
2 * Simple MPI demonstration program
3 *
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 * This file is part of mbed TLS (https://tls.mbed.org)
20 */
21
22 #if !defined(MBEDTLS_CONFIG_FILE)
23 #include "mbedtls/config.h"
24 #else
25 #include MBEDTLS_CONFIG_FILE
26 #endif
27
28 #if defined(MBEDTLS_PLATFORM_C)
29 #include "mbedtls/platform.h"
30 #else
31 #include <stdio.h>
32 #define mbedtls_printf printf
33 #endif
34
35 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_FS_IO)
36 #include "mbedtls/bignum.h"
37
38 #include <stdio.h>
39 #endif
40
41 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_FS_IO)
main(void)42 int main( void )
43 {
44 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_FS_IO not defined.\n");
45 return( 0 );
46 }
47 #else
main(void)48 int main( void )
49 {
50 int ret;
51 mbedtls_mpi E, P, Q, N, H, D, X, Y, Z;
52
53 mbedtls_mpi_init( &E ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q ); mbedtls_mpi_init( &N );
54 mbedtls_mpi_init( &H ); mbedtls_mpi_init( &D ); mbedtls_mpi_init( &X ); mbedtls_mpi_init( &Y );
55 mbedtls_mpi_init( &Z );
56
57 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &P, 10, "2789" ) );
58 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &Q, 10, "3203" ) );
59 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &E, 10, "257" ) );
60 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &N, &P, &Q ) );
61
62 mbedtls_printf( "\n Public key:\n\n" );
63 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " N = ", &N, 10, NULL ) );
64 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " E = ", &E, 10, NULL ) );
65
66 mbedtls_printf( "\n Private key:\n\n" );
67 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " P = ", &P, 10, NULL ) );
68 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " Q = ", &Q, 10, NULL ) );
69
70 #if defined(MBEDTLS_GENPRIME)
71 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &P, &P, 1 ) );
72 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &Q, &Q, 1 ) );
73 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &H, &P, &Q ) );
74 MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &D, &E, &H ) );
75
76 mbedtls_mpi_write_file( " D = E^-1 mod (P-1)*(Q-1) = ",
77 &D, 10, NULL );
78 #else
79 mbedtls_printf("\nTest skipped (MBEDTLS_GENPRIME not defined).\n\n");
80 #endif
81 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &X, 10, "55555" ) );
82 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &Y, &X, &E, &N, NULL ) );
83 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &Z, &Y, &D, &N, NULL ) );
84
85 mbedtls_printf( "\n RSA operation:\n\n" );
86 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " X (plaintext) = ", &X, 10, NULL ) );
87 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " Y (ciphertext) = X^E mod N = ", &Y, 10, NULL ) );
88 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " Z (decrypted) = Y^D mod N = ", &Z, 10, NULL ) );
89 mbedtls_printf( "\n" );
90
91 cleanup:
92 mbedtls_mpi_free( &E ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q ); mbedtls_mpi_free( &N );
93 mbedtls_mpi_free( &H ); mbedtls_mpi_free( &D ); mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y );
94 mbedtls_mpi_free( &Z );
95
96 if( ret != 0 )
97 {
98 mbedtls_printf( "\nAn error occurred.\n" );
99 ret = 1;
100 }
101
102 #if defined(_WIN32)
103 mbedtls_printf( " Press Enter to exit this program.\n" );
104 fflush( stdout ); getchar();
105 #endif
106
107 return( ret );
108 }
109 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_FS_IO */
110
