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#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/certs.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)
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)
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;
if (initialized == 0) {
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
mbedtls_x509_crt_init( &srvcert );
mbedtls_pk_init( &pkey );
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 ) != 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 );
mbedtls_ssl_cookie_init( &cookie_ctx );
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_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.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 );
mbedtls_ctr_drbg_free( &ctr_drbg );
mbedtls_ssl_config_free( &conf );
mbedtls_ssl_free( &ssl );
#else
(void) Data;
(void) Size;
#endif
return 0;
}
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