xref: /aosp_15_r20/external/mbedtls/programs/pkey/mpi_demo.c (revision 62c56f9862f102b96d72393aff6076c951fb8148)
1*62c56f98SSadaf Ebrahimi /*
2*62c56f98SSadaf Ebrahimi  *  Simple MPI demonstration program
3*62c56f98SSadaf Ebrahimi  *
4*62c56f98SSadaf Ebrahimi  *  Copyright The Mbed TLS Contributors
5*62c56f98SSadaf Ebrahimi  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6*62c56f98SSadaf Ebrahimi  */
7*62c56f98SSadaf Ebrahimi 
8*62c56f98SSadaf Ebrahimi #include "mbedtls/build_info.h"
9*62c56f98SSadaf Ebrahimi 
10*62c56f98SSadaf Ebrahimi #include "mbedtls/platform.h"
11*62c56f98SSadaf Ebrahimi 
12*62c56f98SSadaf Ebrahimi #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_FS_IO)
13*62c56f98SSadaf Ebrahimi #include "mbedtls/bignum.h"
14*62c56f98SSadaf Ebrahimi 
15*62c56f98SSadaf Ebrahimi #include <stdio.h>
16*62c56f98SSadaf Ebrahimi #endif
17*62c56f98SSadaf Ebrahimi 
18*62c56f98SSadaf Ebrahimi #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_FS_IO)
main(void)19*62c56f98SSadaf Ebrahimi int main(void)
20*62c56f98SSadaf Ebrahimi {
21*62c56f98SSadaf Ebrahimi     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_FS_IO not defined.\n");
22*62c56f98SSadaf Ebrahimi     mbedtls_exit(0);
23*62c56f98SSadaf Ebrahimi }
24*62c56f98SSadaf Ebrahimi #else
25*62c56f98SSadaf Ebrahimi 
26*62c56f98SSadaf Ebrahimi 
main(void)27*62c56f98SSadaf Ebrahimi int main(void)
28*62c56f98SSadaf Ebrahimi {
29*62c56f98SSadaf Ebrahimi     int ret = 1;
30*62c56f98SSadaf Ebrahimi     int exit_code = MBEDTLS_EXIT_FAILURE;
31*62c56f98SSadaf Ebrahimi     mbedtls_mpi E, P, Q, N, H, D, X, Y, Z;
32*62c56f98SSadaf Ebrahimi 
33*62c56f98SSadaf Ebrahimi     mbedtls_mpi_init(&E); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q); mbedtls_mpi_init(&N);
34*62c56f98SSadaf Ebrahimi     mbedtls_mpi_init(&H); mbedtls_mpi_init(&D); mbedtls_mpi_init(&X); mbedtls_mpi_init(&Y);
35*62c56f98SSadaf Ebrahimi     mbedtls_mpi_init(&Z);
36*62c56f98SSadaf Ebrahimi 
37*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_read_string(&P, 10, "2789"));
38*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_read_string(&Q, 10, "3203"));
39*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_read_string(&E, 10,  "257"));
40*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&N, &P, &Q));
41*62c56f98SSadaf Ebrahimi 
42*62c56f98SSadaf Ebrahimi     mbedtls_printf("\n  Public key:\n\n");
43*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  N = ", &N, 10, NULL));
44*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  E = ", &E, 10, NULL));
45*62c56f98SSadaf Ebrahimi 
46*62c56f98SSadaf Ebrahimi     mbedtls_printf("\n  Private key:\n\n");
47*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  P = ", &P, 10, NULL));
48*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  Q = ", &Q, 10, NULL));
49*62c56f98SSadaf Ebrahimi 
50*62c56f98SSadaf Ebrahimi #if defined(MBEDTLS_GENPRIME)
51*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_sub_int(&P, &P, 1));
52*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_sub_int(&Q, &Q, 1));
53*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&H, &P, &Q));
54*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_inv_mod(&D, &E, &H));
55*62c56f98SSadaf Ebrahimi 
56*62c56f98SSadaf Ebrahimi     mbedtls_mpi_write_file("  D = E^-1 mod (P-1)*(Q-1) = ",
57*62c56f98SSadaf Ebrahimi                            &D, 10, NULL);
58*62c56f98SSadaf Ebrahimi #else
59*62c56f98SSadaf Ebrahimi     mbedtls_printf("\nTest skipped (MBEDTLS_GENPRIME not defined).\n\n");
60*62c56f98SSadaf Ebrahimi #endif
61*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_read_string(&X, 10, "55555"));
62*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&Y, &X, &E, &N, NULL));
63*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&Z, &Y, &D, &N, NULL));
64*62c56f98SSadaf Ebrahimi 
65*62c56f98SSadaf Ebrahimi     mbedtls_printf("\n  RSA operation:\n\n");
66*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  X (plaintext)  = ", &X, 10, NULL));
67*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  Y (ciphertext) = X^E mod N = ", &Y, 10, NULL));
68*62c56f98SSadaf Ebrahimi     MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("  Z (decrypted)  = Y^D mod N = ", &Z, 10, NULL));
69*62c56f98SSadaf Ebrahimi     mbedtls_printf("\n");
70*62c56f98SSadaf Ebrahimi 
71*62c56f98SSadaf Ebrahimi     exit_code = MBEDTLS_EXIT_SUCCESS;
72*62c56f98SSadaf Ebrahimi 
73*62c56f98SSadaf Ebrahimi cleanup:
74*62c56f98SSadaf Ebrahimi     mbedtls_mpi_free(&E); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q); mbedtls_mpi_free(&N);
75*62c56f98SSadaf Ebrahimi     mbedtls_mpi_free(&H); mbedtls_mpi_free(&D); mbedtls_mpi_free(&X); mbedtls_mpi_free(&Y);
76*62c56f98SSadaf Ebrahimi     mbedtls_mpi_free(&Z);
77*62c56f98SSadaf Ebrahimi 
78*62c56f98SSadaf Ebrahimi     if (exit_code != MBEDTLS_EXIT_SUCCESS) {
79*62c56f98SSadaf Ebrahimi         mbedtls_printf("\nAn error occurred.\n");
80*62c56f98SSadaf Ebrahimi     }
81*62c56f98SSadaf Ebrahimi 
82*62c56f98SSadaf Ebrahimi     mbedtls_exit(exit_code);
83*62c56f98SSadaf Ebrahimi }
84*62c56f98SSadaf Ebrahimi #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_FS_IO */
85