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#include "mbedtls/ssl.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/certs.h"
#include "mbedtls/ssl_ticket.h"
#include "common.h"
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#if defined(MBEDTLS_SSL_SRV_C) && \
defined(MBEDTLS_ENTROPY_C) && \
defined(MBEDTLS_CTR_DRBG_C)
const char *pers = "fuzz_server";
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
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
#endif // MBEDTLS_SSL_SRV_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
#if defined(MBEDTLS_SSL_SRV_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;
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
mbedtls_ssl_ticket_context ticket_ctx;
#endif
unsigned char buf[4096];
fuzzBufferOffset_t biomemfuzz;
uint8_t options;
//we take 1 byte as options input
if (Size < 1) {
return 0;
}
options = Data[Size - 1];
if (initialized == 0) {
#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C) && \
defined(MBEDTLS_CERTS_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
alpn_list[0] = "HTTP";
alpn_list[1] = "fuzzalpn";
alpn_list[2] = NULL;
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_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
mbedtls_ssl_ticket_init(&ticket_ctx);
#endif
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_STREAM,
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
mbedtls_ssl_conf_cert_req_ca_list(&conf,
(options &
0x1) ? MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED : MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED);
#if defined(MBEDTLS_SSL_ALPN)
if (options & 0x2) {
mbedtls_ssl_conf_alpn_protocols(&conf, alpn_list);
}
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
if (options & 0x4) {
if (mbedtls_ssl_ticket_setup(&ticket_ctx,
dummy_random, &ctr_drbg,
MBEDTLS_CIPHER_AES_256_GCM,
86400) != 0) {
goto exit;
}
mbedtls_ssl_conf_session_tickets_cb(&conf,
mbedtls_ssl_ticket_write,
mbedtls_ssl_ticket_parse,
&ticket_ctx);
}
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
mbedtls_ssl_conf_truncated_hmac(&conf,
(options &
0x8) ? 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_ENABLED : MBEDTLS_SSL_ETM_DISABLED);
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
if (options & 0x40) {
mbedtls_ssl_conf_psk(&conf, psk, sizeof(psk),
(const unsigned char *) psk_id, sizeof(psk_id) - 1);
}
#endif
#if defined(MBEDTLS_SSL_RENEGOTIATION)
mbedtls_ssl_conf_renegotiation(&conf,
(options &
0x80) ? MBEDTLS_SSL_RENEGOTIATION_ENABLED : MBEDTLS_SSL_RENEGOTIATION_DISABLED);
#endif
if (mbedtls_ssl_setup(&ssl, &conf) != 0) {
goto exit;
}
biomemfuzz.Data = Data;
biomemfuzz.Size = Size-1;
biomemfuzz.Offset = 0;
mbedtls_ssl_set_bio(&ssl, &biomemfuzz, dummy_send, fuzz_recv, NULL);
mbedtls_ssl_session_reset(&ssl);
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:
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
mbedtls_ssl_ticket_free(&ticket_ctx);
#endif
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_SRV_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
return 0;
}
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