1 /*
2 * RSA simple data encryption 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 #include "mbedtls/build_info.h"
21
22 #include "mbedtls/platform.h"
23
24 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_RSA_C) && \
25 defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_FS_IO) && \
26 defined(MBEDTLS_CTR_DRBG_C)
27 #include "mbedtls/rsa.h"
28 #include "mbedtls/entropy.h"
29 #include "mbedtls/ctr_drbg.h"
30
31 #include <string.h>
32 #endif
33
34 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) || \
35 !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_FS_IO) || \
36 !defined(MBEDTLS_CTR_DRBG_C)
main(void)37 int main(void)
38 {
39 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
40 "MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO and/or "
41 "MBEDTLS_CTR_DRBG_C not defined.\n");
42 mbedtls_exit(0);
43 }
44 #else
45
46
main(int argc,char * argv[])47 int main(int argc, char *argv[])
48 {
49 FILE *f;
50 int ret = 1;
51 int exit_code = MBEDTLS_EXIT_FAILURE;
52 size_t i;
53 mbedtls_rsa_context rsa;
54 mbedtls_entropy_context entropy;
55 mbedtls_ctr_drbg_context ctr_drbg;
56 unsigned char input[1024];
57 unsigned char buf[512];
58 const char *pers = "rsa_encrypt";
59 mbedtls_mpi N, E;
60
61 if (argc != 2) {
62 mbedtls_printf("usage: rsa_encrypt <string of max 100 characters>\n");
63
64 #if defined(_WIN32)
65 mbedtls_printf("\n");
66 #endif
67
68 mbedtls_exit(exit_code);
69 }
70
71 mbedtls_printf("\n . Seeding the random number generator...");
72 fflush(stdout);
73
74 mbedtls_mpi_init(&N); mbedtls_mpi_init(&E);
75 mbedtls_rsa_init(&rsa);
76 mbedtls_ctr_drbg_init(&ctr_drbg);
77 mbedtls_entropy_init(&entropy);
78
79 ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func,
80 &entropy, (const unsigned char *) pers,
81 strlen(pers));
82 if (ret != 0) {
83 mbedtls_printf(" failed\n ! mbedtls_ctr_drbg_seed returned %d\n",
84 ret);
85 goto exit;
86 }
87
88 mbedtls_printf("\n . Reading public key from rsa_pub.txt");
89 fflush(stdout);
90
91 if ((f = fopen("rsa_pub.txt", "rb")) == NULL) {
92 mbedtls_printf(" failed\n ! Could not open rsa_pub.txt\n" \
93 " ! Please run rsa_genkey first\n\n");
94 goto exit;
95 }
96
97 if ((ret = mbedtls_mpi_read_file(&N, 16, f)) != 0 ||
98 (ret = mbedtls_mpi_read_file(&E, 16, f)) != 0) {
99 mbedtls_printf(" failed\n ! mbedtls_mpi_read_file returned %d\n\n",
100 ret);
101 fclose(f);
102 goto exit;
103 }
104 fclose(f);
105
106 if ((ret = mbedtls_rsa_import(&rsa, &N, NULL, NULL, NULL, &E)) != 0) {
107 mbedtls_printf(" failed\n ! mbedtls_rsa_import returned %d\n\n",
108 ret);
109 goto exit;
110 }
111
112 if (strlen(argv[1]) > 100) {
113 mbedtls_printf(" Input data larger than 100 characters.\n\n");
114 goto exit;
115 }
116
117 memcpy(input, argv[1], strlen(argv[1]));
118
119 /*
120 * Calculate the RSA encryption of the hash.
121 */
122 mbedtls_printf("\n . Generating the RSA encrypted value");
123 fflush(stdout);
124
125 ret = mbedtls_rsa_pkcs1_encrypt(&rsa, mbedtls_ctr_drbg_random,
126 &ctr_drbg, strlen(argv[1]), input, buf);
127 if (ret != 0) {
128 mbedtls_printf(" failed\n ! mbedtls_rsa_pkcs1_encrypt returned %d\n\n",
129 ret);
130 goto exit;
131 }
132
133 /*
134 * Write the signature into result-enc.txt
135 */
136 if ((f = fopen("result-enc.txt", "wb+")) == NULL) {
137 mbedtls_printf(" failed\n ! Could not create %s\n\n", "result-enc.txt");
138 goto exit;
139 }
140
141 for (i = 0; i < rsa.MBEDTLS_PRIVATE(len); i++) {
142 mbedtls_fprintf(f, "%02X%s", buf[i],
143 (i + 1) % 16 == 0 ? "\r\n" : " ");
144 }
145
146 fclose(f);
147
148 mbedtls_printf("\n . Done (created \"%s\")\n\n", "result-enc.txt");
149
150 exit_code = MBEDTLS_EXIT_SUCCESS;
151
152 exit:
153 mbedtls_mpi_free(&N); mbedtls_mpi_free(&E);
154 mbedtls_ctr_drbg_free(&ctr_drbg);
155 mbedtls_entropy_free(&entropy);
156 mbedtls_rsa_free(&rsa);
157
158 mbedtls_exit(exit_code);
159 }
160 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_ENTROPY_C &&
161 MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */
162
