mbedtls/programs/fuzz/fuzz_privkey.c
Gilles Peskine d5f68976e8 fuzz_pubkey, fuzz_privkey: no real need to access private fields
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2024-02-22 12:05:35 +01:00

105 lines
3.3 KiB
C

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "mbedtls/pk.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "common.h"
//4 Kb should be enough for every bug ;-)
#define MAX_LEN 0x1000
#if defined(MBEDTLS_PK_PARSE_C) && defined(MBEDTLS_CTR_DRBG_C) && defined(MBEDTLS_ENTROPY_C)
const char *pers = "fuzz_privkey";
#endif // MBEDTLS_PK_PARSE_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_ENTROPY_C
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
#if defined(MBEDTLS_PK_PARSE_C) && defined(MBEDTLS_CTR_DRBG_C) && defined(MBEDTLS_ENTROPY_C)
int ret;
mbedtls_pk_context pk;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_entropy_context entropy;
if (Size > MAX_LEN) {
//only work on small inputs
Size = MAX_LEN;
}
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_entropy_init(&entropy);
mbedtls_pk_init(&pk);
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_status_t status = psa_crypto_init();
if (status != PSA_SUCCESS) {
goto exit;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if (mbedtls_ctr_drbg_seed(&ctr_drbg, dummy_entropy, &entropy,
(const unsigned char *) pers, strlen(pers)) != 0) {
goto exit;
}
ret = mbedtls_pk_parse_key(&pk, Data, Size, NULL, 0,
dummy_random, &ctr_drbg);
if (ret == 0) {
#if defined(MBEDTLS_RSA_C)
if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_RSA) {
mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
mbedtls_rsa_context *rsa;
mbedtls_mpi_init(&N); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
mbedtls_mpi_init(&D); mbedtls_mpi_init(&E); mbedtls_mpi_init(&DP);
mbedtls_mpi_init(&DQ); mbedtls_mpi_init(&QP);
rsa = mbedtls_pk_rsa(pk);
if (mbedtls_rsa_export(rsa, &N, &P, &Q, &D, &E) != 0) {
abort();
}
if (mbedtls_rsa_export_crt(rsa, &DP, &DQ, &QP) != 0) {
abort();
}
mbedtls_mpi_free(&N); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
mbedtls_mpi_free(&D); mbedtls_mpi_free(&E); mbedtls_mpi_free(&DP);
mbedtls_mpi_free(&DQ); mbedtls_mpi_free(&QP);
} else
#endif
#if defined(MBEDTLS_ECP_C)
if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY ||
mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY_DH) {
mbedtls_ecp_keypair *ecp = mbedtls_pk_ec(pk);
mbedtls_ecp_group_id grp_id = mbedtls_ecp_keypair_get_group_id(ecp);
const mbedtls_ecp_curve_info *curve_info =
mbedtls_ecp_curve_info_from_grp_id(grp_id);
/* If the curve is not supported, the key should not have been
* accepted. */
if (curve_info == NULL) {
abort();
}
} else
#endif
{
/* The key is valid but is not of a supported type.
* This should not happen. */
abort();
}
}
exit:
mbedtls_entropy_free(&entropy);
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_pk_free(&pk);
#if defined(MBEDTLS_USE_PSA_CRYPTO)
mbedtls_psa_crypto_free();
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#else
(void) Data;
(void) Size;
#endif // MBEDTLS_PK_PARSE_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_ENTROPY_C
return 0;
}