mbedtls/programs/fuzz/fuzz_dtlsclient.c
Gilles Peskine 72da8b3521 Don't authorize private access to fields where not actually needed
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2024-02-22 12:07:29 +01:00

138 lines
3.7 KiB
C

#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include "common.h"
#include "mbedtls/ssl.h"
#if defined(MBEDTLS_SSL_PROTO_DTLS)
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/timing.h"
#include "test/certs.h"
#if defined(MBEDTLS_SSL_CLI_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_C) && \
defined(MBEDTLS_TIMING_C)
static int initialized = 0;
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
static mbedtls_x509_crt cacert;
#endif
const char *pers = "fuzz_dtlsclient";
#endif
#endif // MBEDTLS_SSL_PROTO_DTLS
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
#if defined(MBEDTLS_SSL_PROTO_DTLS) && \
defined(MBEDTLS_SSL_CLI_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_C) && \
defined(MBEDTLS_TIMING_C)
int ret;
size_t len;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_entropy_context entropy;
mbedtls_timing_delay_context timer;
unsigned char buf[4096];
fuzzBufferOffset_t biomemfuzz;
if (initialized == 0) {
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
mbedtls_x509_crt_init(&cacert);
if (mbedtls_x509_crt_parse(&cacert, (const unsigned char *) mbedtls_test_cas_pem,
mbedtls_test_cas_pem_len) != 0) {
return 1;
}
#endif
dummy_init();
initialized = 1;
}
mbedtls_ssl_init(&ssl);
mbedtls_ssl_config_init(&conf);
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_entropy_init(&entropy);
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_status_t status = psa_crypto_init();
if (status != PSA_SUCCESS) {
goto exit;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
srand(1);
if (mbedtls_ctr_drbg_seed(&ctr_drbg, dummy_entropy, &entropy,
(const unsigned char *) pers, strlen(pers)) != 0) {
goto exit;
}
if (mbedtls_ssl_config_defaults(&conf,
MBEDTLS_SSL_IS_CLIENT,
MBEDTLS_SSL_TRANSPORT_DATAGRAM,
MBEDTLS_SSL_PRESET_DEFAULT) != 0) {
goto exit;
}
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
mbedtls_ssl_conf_ca_chain(&conf, &cacert, NULL);
#endif
mbedtls_ssl_conf_authmode(&conf, MBEDTLS_SSL_VERIFY_NONE);
mbedtls_ssl_conf_rng(&conf, dummy_random, &ctr_drbg);
if (mbedtls_ssl_setup(&ssl, &conf) != 0) {
goto exit;
}
mbedtls_ssl_set_timer_cb(&ssl, &timer, mbedtls_timing_set_delay,
mbedtls_timing_get_delay);
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
if (mbedtls_ssl_set_hostname(&ssl, "localhost") != 0) {
goto exit;
}
#endif
biomemfuzz.Data = Data;
biomemfuzz.Size = Size;
biomemfuzz.Offset = 0;
mbedtls_ssl_set_bio(&ssl, &biomemfuzz, dummy_send, fuzz_recv, fuzz_recv_timeout);
ret = mbedtls_ssl_handshake(&ssl);
if (ret == 0) {
//keep reading data from server until the end
do {
len = sizeof(buf) - 1;
ret = mbedtls_ssl_read(&ssl, buf, len);
if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
continue;
} else if (ret <= 0) {
//EOF or error
break;
}
} while (1);
}
exit:
mbedtls_entropy_free(&entropy);
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_ssl_config_free(&conf);
mbedtls_ssl_free(&ssl);
#if defined(MBEDTLS_USE_PSA_CRYPTO)
mbedtls_psa_crypto_free();
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#else
(void) Data;
(void) Size;
#endif
return 0;
}