1 #define MBEDTLS_ALLOW_PRIVATE_ACCESS
2
3 #include <stdint.h>
4 #include <stdlib.h>
5 #include <string.h>
6 #include "mbedtls/pk.h"
7 #include "mbedtls/entropy.h"
8 #include "mbedtls/ctr_drbg.h"
9 #include "common.h"
10
11 //4 Kb should be enough for every bug ;-)
12 #define MAX_LEN 0x1000
13
14 #if defined(MBEDTLS_PK_PARSE_C) && defined(MBEDTLS_CTR_DRBG_C) && defined(MBEDTLS_ENTROPY_C)
15 const char *pers = "fuzz_privkey";
16 #endif // MBEDTLS_PK_PARSE_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_ENTROPY_C
17
LLVMFuzzerTestOneInput(const uint8_t * Data,size_t Size)18 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
19 {
20 #if defined(MBEDTLS_PK_PARSE_C) && defined(MBEDTLS_CTR_DRBG_C) && defined(MBEDTLS_ENTROPY_C)
21 int ret;
22 mbedtls_pk_context pk;
23 mbedtls_ctr_drbg_context ctr_drbg;
24 mbedtls_entropy_context entropy;
25
26 if (Size > MAX_LEN) {
27 //only work on small inputs
28 Size = MAX_LEN;
29 }
30
31 mbedtls_ctr_drbg_init(&ctr_drbg);
32 mbedtls_entropy_init(&entropy);
33 mbedtls_pk_init(&pk);
34
35 #if defined(MBEDTLS_USE_PSA_CRYPTO)
36 psa_status_t status = psa_crypto_init();
37 if (status != PSA_SUCCESS) {
38 goto exit;
39 }
40 #endif /* MBEDTLS_USE_PSA_CRYPTO */
41
42 if (mbedtls_ctr_drbg_seed(&ctr_drbg, dummy_entropy, &entropy,
43 (const unsigned char *) pers, strlen(pers)) != 0) {
44 goto exit;
45 }
46
47 ret = mbedtls_pk_parse_key(&pk, Data, Size, NULL, 0,
48 dummy_random, &ctr_drbg);
49 if (ret == 0) {
50 #if defined(MBEDTLS_RSA_C)
51 if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_RSA) {
52 mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
53 mbedtls_rsa_context *rsa;
54
55 mbedtls_mpi_init(&N); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
56 mbedtls_mpi_init(&D); mbedtls_mpi_init(&E); mbedtls_mpi_init(&DP);
57 mbedtls_mpi_init(&DQ); mbedtls_mpi_init(&QP);
58
59 rsa = mbedtls_pk_rsa(pk);
60 if (mbedtls_rsa_export(rsa, &N, &P, &Q, &D, &E) != 0) {
61 abort();
62 }
63 if (mbedtls_rsa_export_crt(rsa, &DP, &DQ, &QP) != 0) {
64 abort();
65 }
66
67 mbedtls_mpi_free(&N); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
68 mbedtls_mpi_free(&D); mbedtls_mpi_free(&E); mbedtls_mpi_free(&DP);
69 mbedtls_mpi_free(&DQ); mbedtls_mpi_free(&QP);
70 } else
71 #endif
72 #if defined(MBEDTLS_ECP_C)
73 if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY ||
74 mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY_DH) {
75 mbedtls_ecp_keypair *ecp = mbedtls_pk_ec(pk);
76 mbedtls_ecp_group_id grp_id = ecp->grp.id;
77 const mbedtls_ecp_curve_info *curve_info =
78 mbedtls_ecp_curve_info_from_grp_id(grp_id);
79
80 /* If the curve is not supported, the key should not have been
81 * accepted. */
82 if (curve_info == NULL) {
83 abort();
84 }
85 } else
86 #endif
87 {
88 /* The key is valid but is not of a supported type.
89 * This should not happen. */
90 abort();
91 }
92 }
93 exit:
94 mbedtls_entropy_free(&entropy);
95 mbedtls_ctr_drbg_free(&ctr_drbg);
96 mbedtls_pk_free(&pk);
97 #if defined(MBEDTLS_USE_PSA_CRYPTO)
98 mbedtls_psa_crypto_free();
99 #endif /* MBEDTLS_USE_PSA_CRYPTO */
100 #else
101 (void) Data;
102 (void) Size;
103 #endif // MBEDTLS_PK_PARSE_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_ENTROPY_C
104
105 return 0;
106 }
107