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#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include "common.h"
#include "mbedtls/ssl.h"
#include "test/certs.h"
#if defined(MBEDTLS_SSL_PROTO_DTLS)
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/timing.h"
#include "mbedtls/ssl_cookie.h"
#if defined(MBEDTLS_SSL_SRV_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_C) && \
defined(MBEDTLS_TIMING_C) && \
(defined(MBEDTLS_MD_CAN_SHA384) || \
defined(MBEDTLS_MD_CAN_SHA256))
const char *pers = "fuzz_dtlsserver";
const unsigned char client_ip[4] = { 0x7F, 0, 0, 1 };
static int initialized = 0;
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
static mbedtls_x509_crt srvcert;
static mbedtls_pk_context pkey;
#endif
#endif
#endif // MBEDTLS_SSL_PROTO_DTLS
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
#if defined(MBEDTLS_SSL_PROTO_DTLS) && \
defined(MBEDTLS_SSL_SRV_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_C) && \
defined(MBEDTLS_TIMING_C) && \
(defined(MBEDTLS_MD_CAN_SHA384) || \
defined(MBEDTLS_MD_CAN_SHA256))
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;
mbedtls_ssl_cookie_ctx cookie_ctx;
unsigned char buf[4096];
fuzzBufferOffset_t biomemfuzz;
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_entropy_init(&entropy);
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
mbedtls_x509_crt_init(&srvcert);
mbedtls_pk_init(&pkey);
#endif
mbedtls_ssl_init(&ssl);
mbedtls_ssl_config_init(&conf);
mbedtls_ssl_cookie_init(&cookie_ctx);
#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;
}
if (initialized == 0) {
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
if (mbedtls_x509_crt_parse(&srvcert, (const unsigned char *) mbedtls_test_srv_crt,
mbedtls_test_srv_crt_len) != 0) {
return 1;
}
if (mbedtls_x509_crt_parse(&srvcert, (const unsigned char *) mbedtls_test_cas_pem,
mbedtls_test_cas_pem_len) != 0) {
return 1;
}
if (mbedtls_pk_parse_key(&pkey, (const unsigned char *) mbedtls_test_srv_key,
mbedtls_test_srv_key_len, NULL, 0,
dummy_random, &ctr_drbg) != 0) {
return 1;
}
#endif
dummy_init();
initialized = 1;
}
if (mbedtls_ssl_config_defaults(&conf,
MBEDTLS_SSL_IS_SERVER,
MBEDTLS_SSL_TRANSPORT_DATAGRAM,
MBEDTLS_SSL_PRESET_DEFAULT) != 0) {
goto exit;
}
srand(1);
mbedtls_ssl_conf_rng(&conf, dummy_random, &ctr_drbg);
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
mbedtls_ssl_conf_ca_chain(&conf, srvcert.next, NULL);
if (mbedtls_ssl_conf_own_cert(&conf, &srvcert, &pkey) != 0) {
goto exit;
}
#endif
if (mbedtls_ssl_cookie_setup(&cookie_ctx, dummy_random, &ctr_drbg) != 0) {
goto exit;
}
mbedtls_ssl_conf_dtls_cookies(&conf,
mbedtls_ssl_cookie_write,
mbedtls_ssl_cookie_check,
&cookie_ctx);
if (mbedtls_ssl_setup(&ssl, &conf) != 0) {
goto exit;
}
mbedtls_ssl_set_timer_cb(&ssl, &timer, mbedtls_timing_set_delay,
mbedtls_timing_get_delay);
biomemfuzz.Data = Data;
biomemfuzz.Size = Size;
biomemfuzz.Offset = 0;
mbedtls_ssl_set_bio(&ssl, &biomemfuzz, dummy_send, fuzz_recv, fuzz_recv_timeout);
if (mbedtls_ssl_set_client_transport_id(&ssl, client_ip, sizeof(client_ip)) != 0) {
goto exit;
}
ret = mbedtls_ssl_handshake(&ssl);
if (ret == MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED) {
biomemfuzz.Offset = ssl.MBEDTLS_PRIVATE(next_record_offset);
mbedtls_ssl_session_reset(&ssl);
mbedtls_ssl_set_bio(&ssl, &biomemfuzz, dummy_send, fuzz_recv, fuzz_recv_timeout);
if (mbedtls_ssl_set_client_transport_id(&ssl, client_ip, sizeof(client_ip)) != 0) {
goto exit;
}
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_ssl_cookie_free(&cookie_ctx);
mbedtls_entropy_free(&entropy);
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
mbedtls_pk_free(&pkey);
mbedtls_x509_crt_free(&srvcert);
#endif
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;
}
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