1 /*
2 * Simple MPI demonstration program
3 *
4 * Copyright The Mbed TLS Contributors
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
20 #if !defined(MBEDTLS_CONFIG_FILE)
21 #include "mbedtls/config.h"
22 #else
23 #include MBEDTLS_CONFIG_FILE
24 #endif
25
26 #if defined(MBEDTLS_PLATFORM_C)
27 #include "mbedtls/platform.h"
28 #else
29 #include <stdio.h>
30 #include <stdlib.h>
31 #define mbedtls_printf printf
32 #define mbedtls_exit exit
33 #define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
34 #define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
35 #endif /* MBEDTLS_PLATFORM_C */
36
37 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_FS_IO)
38 #include "mbedtls/bignum.h"
39
40 #include <stdio.h>
41 #endif
42
43 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_FS_IO)
main(void)44 int main( void )
45 {
46 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_FS_IO not defined.\n");
47 mbedtls_exit( 0 );
48 }
49 #else
50
51
main(void)52 int main( void )
53 {
54 int ret = 1;
55 int exit_code = MBEDTLS_EXIT_FAILURE;
56 mbedtls_mpi E, P, Q, N, H, D, X, Y, Z;
57
58 mbedtls_mpi_init( &E ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q ); mbedtls_mpi_init( &N );
59 mbedtls_mpi_init( &H ); mbedtls_mpi_init( &D ); mbedtls_mpi_init( &X ); mbedtls_mpi_init( &Y );
60 mbedtls_mpi_init( &Z );
61
62 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &P, 10, "2789" ) );
63 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &Q, 10, "3203" ) );
64 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &E, 10, "257" ) );
65 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &N, &P, &Q ) );
66
67 mbedtls_printf( "\n Public key:\n\n" );
68 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " N = ", &N, 10, NULL ) );
69 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " E = ", &E, 10, NULL ) );
70
71 mbedtls_printf( "\n Private key:\n\n" );
72 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " P = ", &P, 10, NULL ) );
73 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " Q = ", &Q, 10, NULL ) );
74
75 #if defined(MBEDTLS_GENPRIME)
76 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &P, &P, 1 ) );
77 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &Q, &Q, 1 ) );
78 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &H, &P, &Q ) );
79 MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &D, &E, &H ) );
80
81 mbedtls_mpi_write_file( " D = E^-1 mod (P-1)*(Q-1) = ",
82 &D, 10, NULL );
83 #else
84 mbedtls_printf("\nTest skipped (MBEDTLS_GENPRIME not defined).\n\n");
85 #endif
86 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &X, 10, "55555" ) );
87 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &Y, &X, &E, &N, NULL ) );
88 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &Z, &Y, &D, &N, NULL ) );
89
90 mbedtls_printf( "\n RSA operation:\n\n" );
91 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " X (plaintext) = ", &X, 10, NULL ) );
92 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " Y (ciphertext) = X^E mod N = ", &Y, 10, NULL ) );
93 MBEDTLS_MPI_CHK( mbedtls_mpi_write_file( " Z (decrypted) = Y^D mod N = ", &Z, 10, NULL ) );
94 mbedtls_printf( "\n" );
95
96 exit_code = MBEDTLS_EXIT_SUCCESS;
97
98 cleanup:
99 mbedtls_mpi_free( &E ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q ); mbedtls_mpi_free( &N );
100 mbedtls_mpi_free( &H ); mbedtls_mpi_free( &D ); mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y );
101 mbedtls_mpi_free( &Z );
102
103 if( exit_code != MBEDTLS_EXIT_SUCCESS )
104 {
105 mbedtls_printf( "\nAn error occurred.\n" );
106 }
107
108 #if defined(_WIN32)
109 mbedtls_printf( " Press Enter to exit this program.\n" );
110 fflush( stdout ); getchar();
111 #endif
112
113 mbedtls_exit( exit_code );
114 }
115 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_FS_IO */
116
