1 /*
2 * RSA/SHA-256 signature creation program
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7
8 #include "mbedtls/build_info.h"
9
10 #include "mbedtls/platform.h"
11 /* md.h is included this early since MD_CAN_XXX macros are defined there. */
12 #include "mbedtls/md.h"
13
14 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) || \
15 !defined(MBEDTLS_MD_CAN_SHA256) || !defined(MBEDTLS_MD_C) || \
16 !defined(MBEDTLS_FS_IO)
main(void)17 int main(void)
18 {
19 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
20 "MBEDTLS_MD_C and/or "
21 "MBEDTLS_MD_CAN_SHA256 and/or MBEDTLS_FS_IO not defined.\n");
22 mbedtls_exit(0);
23 }
24 #else
25
26 #include "mbedtls/rsa.h"
27
28 #include <stdio.h>
29 #include <string.h>
30
31
main(int argc,char * argv[])32 int main(int argc, char *argv[])
33 {
34 FILE *f;
35 int ret = 1;
36 int exit_code = MBEDTLS_EXIT_FAILURE;
37 size_t i;
38 mbedtls_rsa_context rsa;
39 unsigned char hash[32];
40 unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
41 char filename[512];
42 mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
43
44 mbedtls_rsa_init(&rsa);
45
46 mbedtls_mpi_init(&N); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
47 mbedtls_mpi_init(&D); mbedtls_mpi_init(&E); mbedtls_mpi_init(&DP);
48 mbedtls_mpi_init(&DQ); mbedtls_mpi_init(&QP);
49
50 if (argc != 2) {
51 mbedtls_printf("usage: rsa_sign <filename>\n");
52
53 #if defined(_WIN32)
54 mbedtls_printf("\n");
55 #endif
56
57 goto exit;
58 }
59
60 mbedtls_printf("\n . Reading private key from rsa_priv.txt");
61 fflush(stdout);
62
63 if ((f = fopen("rsa_priv.txt", "rb")) == NULL) {
64 mbedtls_printf(" failed\n ! Could not open rsa_priv.txt\n" \
65 " ! Please run rsa_genkey first\n\n");
66 goto exit;
67 }
68
69 if ((ret = mbedtls_mpi_read_file(&N, 16, f)) != 0 ||
70 (ret = mbedtls_mpi_read_file(&E, 16, f)) != 0 ||
71 (ret = mbedtls_mpi_read_file(&D, 16, f)) != 0 ||
72 (ret = mbedtls_mpi_read_file(&P, 16, f)) != 0 ||
73 (ret = mbedtls_mpi_read_file(&Q, 16, f)) != 0 ||
74 (ret = mbedtls_mpi_read_file(&DP, 16, f)) != 0 ||
75 (ret = mbedtls_mpi_read_file(&DQ, 16, f)) != 0 ||
76 (ret = mbedtls_mpi_read_file(&QP, 16, f)) != 0) {
77 mbedtls_printf(" failed\n ! mbedtls_mpi_read_file returned %d\n\n", ret);
78 fclose(f);
79 goto exit;
80 }
81 fclose(f);
82
83 if ((ret = mbedtls_rsa_import(&rsa, &N, &P, &Q, &D, &E)) != 0) {
84 mbedtls_printf(" failed\n ! mbedtls_rsa_import returned %d\n\n",
85 ret);
86 goto exit;
87 }
88
89 if ((ret = mbedtls_rsa_complete(&rsa)) != 0) {
90 mbedtls_printf(" failed\n ! mbedtls_rsa_complete returned %d\n\n",
91 ret);
92 goto exit;
93 }
94
95 mbedtls_printf("\n . Checking the private key");
96 fflush(stdout);
97 if ((ret = mbedtls_rsa_check_privkey(&rsa)) != 0) {
98 mbedtls_printf(" failed\n ! mbedtls_rsa_check_privkey failed with -0x%0x\n",
99 (unsigned int) -ret);
100 goto exit;
101 }
102
103 /*
104 * Compute the SHA-256 hash of the input file,
105 * then calculate the RSA signature of the hash.
106 */
107 mbedtls_printf("\n . Generating the RSA/SHA-256 signature");
108 fflush(stdout);
109
110 if ((ret = mbedtls_md_file(
111 mbedtls_md_info_from_type(MBEDTLS_MD_SHA256),
112 argv[1], hash)) != 0) {
113 mbedtls_printf(" failed\n ! Could not open or read %s\n\n", argv[1]);
114 goto exit;
115 }
116
117 if ((ret = mbedtls_rsa_pkcs1_sign(&rsa, NULL, NULL, MBEDTLS_MD_SHA256,
118 32, hash, buf)) != 0) {
119 mbedtls_printf(" failed\n ! mbedtls_rsa_pkcs1_sign returned -0x%0x\n\n",
120 (unsigned int) -ret);
121 goto exit;
122 }
123
124 /*
125 * Write the signature into <filename>.sig
126 */
127 mbedtls_snprintf(filename, sizeof(filename), "%s.sig", argv[1]);
128
129 if ((f = fopen(filename, "wb+")) == NULL) {
130 mbedtls_printf(" failed\n ! Could not create %s\n\n", argv[1]);
131 goto exit;
132 }
133
134 for (i = 0; i < mbedtls_rsa_get_len(&rsa); i++) {
135 mbedtls_fprintf(f, "%02X%s", buf[i],
136 (i + 1) % 16 == 0 ? "\r\n" : " ");
137 }
138
139 fclose(f);
140
141 mbedtls_printf("\n . Done (created \"%s\")\n\n", filename);
142
143 exit_code = MBEDTLS_EXIT_SUCCESS;
144
145 exit:
146
147 mbedtls_rsa_free(&rsa);
148 mbedtls_mpi_free(&N); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
149 mbedtls_mpi_free(&D); mbedtls_mpi_free(&E); mbedtls_mpi_free(&DP);
150 mbedtls_mpi_free(&DQ); mbedtls_mpi_free(&QP);
151
152 mbedtls_exit(exit_code);
153 }
154 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_MD_CAN_SHA256 &&
155 MBEDTLS_FS_IO */
156