xref: /openssl/fuzz/dtlsclient.c (revision b6461792)
1 /*
2  * Copyright 2016-2024 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  * https://www.openssl.org/source/license.html
8  * or in the file LICENSE in the source distribution.
9  */
10 
11 #include <time.h>
12 #include <openssl/rand.h>
13 #include <openssl/ssl.h>
14 #include <openssl/rsa.h>
15 #include <openssl/dsa.h>
16 #include <openssl/ec.h>
17 #include <openssl/dh.h>
18 #include <openssl/err.h>
19 #include "fuzzer.h"
20 
21 /* unused, to avoid warning. */
22 static int idx;
23 
24 #define FUZZTIME 1485898104
25 
26 #define TIME_IMPL(t) { if (t != NULL) *t = FUZZTIME; return FUZZTIME; }
27 
28 /*
29  * This might not work in all cases (and definitely not on Windows
30  * because of the way linkers are) and callees can still get the
31  * current time instead of the fixed time. This will just result
32  * in things not being fully reproducible and have a slightly
33  * different coverage.
34  */
35 #if !defined(_WIN32)
time(time_t * t)36 time_t time(time_t *t) TIME_IMPL(t)
37 #endif
38 
39 int FuzzerInitialize(int *argc, char ***argv)
40 {
41     STACK_OF(SSL_COMP) *comp_methods;
42 
43     FuzzerSetRand();
44     OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS | OPENSSL_INIT_ASYNC, NULL);
45     OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS, NULL);
46     ERR_clear_error();
47     CRYPTO_free_ex_index(0, -1);
48     idx = SSL_get_ex_data_X509_STORE_CTX_idx();
49     comp_methods = SSL_COMP_get_compression_methods();
50     if (comp_methods != NULL)
51         sk_SSL_COMP_sort(comp_methods);
52 
53     return 1;
54 }
55 
FuzzerTestOneInput(const uint8_t * buf,size_t len)56 int FuzzerTestOneInput(const uint8_t *buf, size_t len)
57 {
58     SSL *client = NULL;
59     BIO *in;
60     BIO *out;
61     SSL_CTX *ctx;
62 
63     if (len == 0)
64         return 0;
65 
66     /* This only fuzzes the initial flow from the client so far. */
67     ctx = SSL_CTX_new(DTLS_client_method());
68     if (ctx == NULL)
69         goto end;
70 
71     client = SSL_new(ctx);
72     if (client == NULL)
73         goto end;
74     OPENSSL_assert(SSL_set_min_proto_version(client, 0) == 1);
75     OPENSSL_assert(SSL_set_cipher_list(client, "ALL:eNULL:@SECLEVEL=0") == 1);
76     SSL_set_tlsext_host_name(client, "localhost");
77     in = BIO_new(BIO_s_mem());
78     if (in == NULL)
79         goto end;
80     out = BIO_new(BIO_s_mem());
81     if (out == NULL) {
82         BIO_free(in);
83         goto end;
84     }
85     SSL_set_bio(client, in, out);
86     SSL_set_connect_state(client);
87     OPENSSL_assert((size_t)BIO_write(in, buf, len) == len);
88     if (SSL_do_handshake(client) == 1) {
89         /* Keep reading application data until error or EOF. */
90         uint8_t tmp[1024];
91         for (;;) {
92             if (SSL_read(client, tmp, sizeof(tmp)) <= 0) {
93                 break;
94             }
95         }
96     }
97  end:
98     SSL_free(client);
99     ERR_clear_error();
100     SSL_CTX_free(ctx);
101 
102     return 0;
103 }
104 
FuzzerCleanup(void)105 void FuzzerCleanup(void)
106 {
107     FuzzerClearRand();
108 }
109