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#include "mbedtls/ssl.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/certs.h"
#include "common.h"
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#if defined(MBEDTLS_SSL_CLI_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_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 *alpn_list[3];
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
const unsigned char psk[] = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
};
const char psk_id[] = "Client_identity";
#endif
const char *pers = "fuzz_client";
#endif /* MBEDTLS_SSL_CLI_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
#if defined(MBEDTLS_SSL_CLI_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_C)
int ret;
size_t len;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_entropy_context entropy;
unsigned char buf[4096];
fuzzBufferOffset_t biomemfuzz;
uint16_t options;
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
alpn_list[0] = "HTTP";
alpn_list[1] = "fuzzalpn";
alpn_list[2] = NULL;
dummy_init();
initialized = 1;
}
//we take 1 byte as options input
if (Size < 2) {
return 0;
}
options = (Data[Size - 2] << 8) | Data[Size - 1];
//Avoid warnings if compile options imply no options
(void) options;
mbedtls_ssl_init( &ssl );
mbedtls_ssl_config_init( &conf );
mbedtls_ctr_drbg_init( &ctr_drbg );
mbedtls_entropy_init( &entropy );
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_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT ) != 0 )
goto exit;
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
if (options & 2) {
mbedtls_ssl_conf_psk( &conf, psk, sizeof( psk ),
(const unsigned char *) psk_id, sizeof( psk_id ) - 1 );
}
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
if (options & 4) {
mbedtls_ssl_conf_ca_chain( &conf, &cacert, NULL );
mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_REQUIRED );
} else
#endif
{
mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_NONE );
}
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
mbedtls_ssl_conf_truncated_hmac( &conf, (options & 8) ? MBEDTLS_SSL_TRUNC_HMAC_ENABLED : MBEDTLS_SSL_TRUNC_HMAC_DISABLED);
#endif
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
mbedtls_ssl_conf_extended_master_secret( &conf, (options & 0x10) ? MBEDTLS_SSL_EXTENDED_MS_DISABLED : MBEDTLS_SSL_EXTENDED_MS_ENABLED);
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
mbedtls_ssl_conf_encrypt_then_mac( &conf, (options & 0x20) ? MBEDTLS_SSL_ETM_DISABLED : MBEDTLS_SSL_ETM_ENABLED);
#endif
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
mbedtls_ssl_conf_cbc_record_splitting( &conf, (options & 0x40) ? MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED : MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED );
#endif
#if defined(MBEDTLS_SSL_RENEGOTIATION)
mbedtls_ssl_conf_renegotiation( &conf, (options & 0x80) ? MBEDTLS_SSL_RENEGOTIATION_ENABLED : MBEDTLS_SSL_RENEGOTIATION_DISABLED );
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
mbedtls_ssl_conf_session_tickets( &conf, (options & 0x100) ? MBEDTLS_SSL_SESSION_TICKETS_DISABLED : MBEDTLS_SSL_SESSION_TICKETS_ENABLED );
#endif
#if defined(MBEDTLS_SSL_ALPN)
if (options & 0x200) {
mbedtls_ssl_conf_alpn_protocols( &conf, alpn_list );
}
#endif
//There may be other options to add :
// mbedtls_ssl_conf_cert_profile, mbedtls_ssl_conf_sig_hashes
srand(1);
mbedtls_ssl_conf_rng( &conf, dummy_random, &ctr_drbg );
if( mbedtls_ssl_setup( &ssl, &conf ) != 0 )
goto exit;
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
if ((options & 1) == 0) {
if( mbedtls_ssl_set_hostname( &ssl, "localhost" ) != 0 )
goto exit;
}
#endif
biomemfuzz.Data = Data;
biomemfuzz.Size = Size-2;
biomemfuzz.Offset = 0;
mbedtls_ssl_set_bio( &ssl, &biomemfuzz, dummy_send, fuzz_recv, NULL );
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 );
#else
(void) Data;
(void) Size;
#endif /* MBEDTLS_SSL_CLI_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
return 0;
}
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