1/*
2 *  RSASSA-PSS/SHA-256 signature verification 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/md.h"
29#include "mbedtls/pem.h"
30#include "mbedtls/pk.h"
31
32#include <stdio.h>
33#include <string.h>
34
35
36int main(int argc, char *argv[])
37{
38    FILE *f;
39    int ret = 1;
40    int exit_code = MBEDTLS_EXIT_FAILURE;
41    size_t i;
42    mbedtls_pk_context pk;
43    unsigned char hash[32];
44    unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
45    char filename[512];
46
47    mbedtls_pk_init(&pk);
48
49#if defined(MBEDTLS_USE_PSA_CRYPTO)
50    psa_status_t status = psa_crypto_init();
51    if (status != PSA_SUCCESS) {
52        mbedtls_fprintf(stderr, "Failed to initialize PSA Crypto implementation: %d\n",
53                        (int) status);
54        goto exit;
55    }
56#endif /* MBEDTLS_USE_PSA_CRYPTO */
57
58    if (argc != 3) {
59        mbedtls_printf("usage: rsa_verify_pss <key_file> <filename>\n");
60
61#if defined(_WIN32)
62        mbedtls_printf("\n");
63#endif
64
65        goto exit;
66    }
67
68    mbedtls_printf("\n  . Reading public key from '%s'", argv[1]);
69    fflush(stdout);
70
71    if ((ret = mbedtls_pk_parse_public_keyfile(&pk, argv[1])) != 0) {
72        mbedtls_printf(" failed\n  ! Could not read key from '%s'\n", argv[1]);
73        mbedtls_printf("  ! mbedtls_pk_parse_public_keyfile returned %d\n\n", ret);
74        goto exit;
75    }
76
77    if (!mbedtls_pk_can_do(&pk, MBEDTLS_PK_RSA)) {
78        mbedtls_printf(" failed\n  ! Key is not an RSA key\n");
79        goto exit;
80    }
81
82    if ((ret = mbedtls_rsa_set_padding(mbedtls_pk_rsa(pk),
83                                       MBEDTLS_RSA_PKCS_V21,
84                                       MBEDTLS_MD_SHA256)) != 0) {
85        mbedtls_printf(" failed\n  ! Invalid padding\n");
86        goto exit;
87    }
88
89    /*
90     * Extract the RSA signature from the file
91     */
92    mbedtls_snprintf(filename, 512, "%s.sig", argv[2]);
93
94    if ((f = fopen(filename, "rb")) == NULL) {
95        mbedtls_printf("\n  ! Could not open %s\n\n", filename);
96        goto exit;
97    }
98
99    i = fread(buf, 1, MBEDTLS_MPI_MAX_SIZE, f);
100
101    fclose(f);
102
103    /*
104     * Compute the SHA-256 hash of the input file and
105     * verify the signature
106     */
107    mbedtls_printf("\n  . Verifying 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[2], hash)) != 0) {
113        mbedtls_printf(" failed\n  ! Could not open or read %s\n\n", argv[2]);
114        goto exit;
115    }
116
117    if ((ret = mbedtls_pk_verify(&pk, MBEDTLS_MD_SHA256, hash, 0,
118                                 buf, i)) != 0) {
119        mbedtls_printf(" failed\n  ! mbedtls_pk_verify returned %d\n\n", ret);
120        goto exit;
121    }
122
123    mbedtls_printf("\n  . OK (the signature is valid)\n\n");
124
125    exit_code = MBEDTLS_EXIT_SUCCESS;
126
127exit:
128    mbedtls_pk_free(&pk);
129#if defined(MBEDTLS_USE_PSA_CRYPTO)
130    mbedtls_psa_crypto_free();
131#endif /* MBEDTLS_USE_PSA_CRYPTO */
132
133    mbedtls_exit(exit_code);
134}
135#endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_MD_CAN_SHA256 &&
136          MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO */
137