1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
#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) && \
defined(MBEDTLS_CERTS_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;
}
|
