1/*
2 *  RSASSA-PSS/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_MD_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
15    !defined(MBEDTLS_RSA_C) || !defined(MBEDTLS_MD_CAN_SHA256) ||        \
16    !defined(MBEDTLS_PK_PARSE_C) || !defined(MBEDTLS_FS_IO) ||    \
17    !defined(MBEDTLS_CTR_DRBG_C)
18int main(void)
19{
20    mbedtls_printf("MBEDTLS_MD_C and/or MBEDTLS_ENTROPY_C and/or "
21                   "MBEDTLS_RSA_C and/or MBEDTLS_MD_CAN_SHA256 and/or "
22                   "MBEDTLS_PK_PARSE_C and/or MBEDTLS_FS_IO and/or "
23                   "MBEDTLS_CTR_DRBG_C not defined.\n");
24    mbedtls_exit(0);
25}
26#else
27
28#include "mbedtls/entropy.h"
29#include "mbedtls/ctr_drbg.h"
30#include "mbedtls/rsa.h"
31#include "mbedtls/pk.h"
32
33#include <stdio.h>
34#include <string.h>
35
36
37int main(int argc, char *argv[])
38{
39    FILE *f;
40    int ret = 1;
41    int exit_code = MBEDTLS_EXIT_FAILURE;
42    mbedtls_pk_context pk;
43    mbedtls_entropy_context entropy;
44    mbedtls_ctr_drbg_context ctr_drbg;
45    unsigned char hash[32];
46    unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
47    char filename[512];
48    const char *pers = "rsa_sign_pss";
49    size_t olen = 0;
50
51    mbedtls_entropy_init(&entropy);
52    mbedtls_pk_init(&pk);
53    mbedtls_ctr_drbg_init(&ctr_drbg);
54
55#if defined(MBEDTLS_USE_PSA_CRYPTO)
56    psa_status_t status = psa_crypto_init();
57    if (status != PSA_SUCCESS) {
58        mbedtls_fprintf(stderr, "Failed to initialize PSA Crypto implementation: %d\n",
59                        (int) status);
60        goto exit;
61    }
62#endif /* MBEDTLS_USE_PSA_CRYPTO */
63
64    if (argc != 3) {
65        mbedtls_printf("usage: rsa_sign_pss <key_file> <filename>\n");
66
67#if defined(_WIN32)
68        mbedtls_printf("\n");
69#endif
70
71        goto exit;
72    }
73
74    mbedtls_printf("\n  . Seeding the random number generator...");
75    fflush(stdout);
76
77    if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
78                                     (const unsigned char *) pers,
79                                     strlen(pers))) != 0) {
80        mbedtls_printf(" failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret);
81        goto exit;
82    }
83
84    mbedtls_printf("\n  . Reading private key from '%s'", argv[1]);
85    fflush(stdout);
86
87    if ((ret = mbedtls_pk_parse_keyfile(&pk, argv[1], "",
88                                        mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
89        mbedtls_printf(" failed\n  ! Could not read key from '%s'\n", argv[1]);
90        mbedtls_printf("  ! mbedtls_pk_parse_public_keyfile returned %d\n\n", ret);
91        goto exit;
92    }
93
94    if (!mbedtls_pk_can_do(&pk, MBEDTLS_PK_RSA)) {
95        mbedtls_printf(" failed\n  ! Key is not an RSA key\n");
96        goto exit;
97    }
98
99    if ((ret = mbedtls_rsa_set_padding(mbedtls_pk_rsa(pk),
100                                       MBEDTLS_RSA_PKCS_V21,
101                                       MBEDTLS_MD_SHA256)) != 0) {
102        mbedtls_printf(" failed\n  ! Padding not supported\n");
103        goto exit;
104    }
105
106    /*
107     * Compute the SHA-256 hash of the input file,
108     * then calculate the RSA signature of the hash.
109     */
110    mbedtls_printf("\n  . Generating the RSA/SHA-256 signature");
111    fflush(stdout);
112
113    if ((ret = mbedtls_md_file(
114             mbedtls_md_info_from_type(MBEDTLS_MD_SHA256),
115             argv[2], hash)) != 0) {
116        mbedtls_printf(" failed\n  ! Could not open or read %s\n\n", argv[2]);
117        goto exit;
118    }
119
120    if ((ret = mbedtls_pk_sign(&pk, MBEDTLS_MD_SHA256, hash, 0,
121                               buf, sizeof(buf), &olen,
122                               mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
123        mbedtls_printf(" failed\n  ! mbedtls_pk_sign returned %d\n\n", ret);
124        goto exit;
125    }
126
127    /*
128     * Write the signature into <filename>.sig
129     */
130    mbedtls_snprintf(filename, 512, "%s.sig", argv[2]);
131
132    if ((f = fopen(filename, "wb+")) == NULL) {
133        mbedtls_printf(" failed\n  ! Could not create %s\n\n", filename);
134        goto exit;
135    }
136
137    if (fwrite(buf, 1, olen, f) != olen) {
138        mbedtls_printf("failed\n  ! fwrite failed\n\n");
139        fclose(f);
140        goto exit;
141    }
142
143    fclose(f);
144
145    mbedtls_printf("\n  . Done (created \"%s\")\n\n", filename);
146
147    exit_code = MBEDTLS_EXIT_SUCCESS;
148
149exit:
150    mbedtls_pk_free(&pk);
151    mbedtls_ctr_drbg_free(&ctr_drbg);
152    mbedtls_entropy_free(&entropy);
153#if defined(MBEDTLS_USE_PSA_CRYPTO)
154    mbedtls_psa_crypto_free();
155#endif /* MBEDTLS_USE_PSA_CRYPTO */
156
157    mbedtls_exit(exit_code);
158}
159#endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_RSA_C &&
160          MBEDTLS_MD_CAN_SHA256 && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO &&
161          MBEDTLS_CTR_DRBG_C */
162