1 #define MBEDTLS_ALLOW_PRIVATE_ACCESS
2
3 #include "mbedtls/ssl.h"
4 #include "mbedtls/entropy.h"
5 #include "mbedtls/ctr_drbg.h"
6 #include "test/certs.h"
7 #include "common.h"
8 #include <string.h>
9 #include <stdlib.h>
10 #include <stdint.h>
11
12
13 #if defined(MBEDTLS_SSL_CLI_C) && \
14 defined(MBEDTLS_ENTROPY_C) && \
15 defined(MBEDTLS_CTR_DRBG_C)
16 static int initialized = 0;
17 #if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
18 static mbedtls_x509_crt cacert;
19 #endif
20 const char *alpn_list[3];
21
22
23 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
24 const unsigned char psk[] = {
25 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
26 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
27 };
28 const char psk_id[] = "Client_identity";
29 #endif
30
31 const char *pers = "fuzz_client";
32 #endif /* MBEDTLS_SSL_CLI_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
33
34
LLVMFuzzerTestOneInput(const uint8_t * Data,size_t Size)35 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
36 {
37 #if defined(MBEDTLS_SSL_CLI_C) && \
38 defined(MBEDTLS_ENTROPY_C) && \
39 defined(MBEDTLS_CTR_DRBG_C)
40 int ret;
41 size_t len;
42 mbedtls_ssl_context ssl;
43 mbedtls_ssl_config conf;
44 mbedtls_ctr_drbg_context ctr_drbg;
45 mbedtls_entropy_context entropy;
46 unsigned char buf[4096];
47 fuzzBufferOffset_t biomemfuzz;
48 uint16_t options;
49
50 if (initialized == 0) {
51 #if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
52 mbedtls_x509_crt_init(&cacert);
53 if (mbedtls_x509_crt_parse(&cacert, (const unsigned char *) mbedtls_test_cas_pem,
54 mbedtls_test_cas_pem_len) != 0) {
55 return 1;
56 }
57 #endif
58
59 alpn_list[0] = "HTTP";
60 alpn_list[1] = "fuzzalpn";
61 alpn_list[2] = NULL;
62
63 dummy_init();
64
65 initialized = 1;
66 }
67
68 //we take 1 byte as options input
69 if (Size < 2) {
70 return 0;
71 }
72 options = (Data[Size - 2] << 8) | Data[Size - 1];
73 //Avoid warnings if compile options imply no options
74 (void) options;
75
76 mbedtls_ssl_init(&ssl);
77 mbedtls_ssl_config_init(&conf);
78 mbedtls_ctr_drbg_init(&ctr_drbg);
79 mbedtls_entropy_init(&entropy);
80
81 if (mbedtls_ctr_drbg_seed(&ctr_drbg, dummy_entropy, &entropy,
82 (const unsigned char *) pers, strlen(pers)) != 0) {
83 goto exit;
84 }
85
86 if (mbedtls_ssl_config_defaults(&conf,
87 MBEDTLS_SSL_IS_CLIENT,
88 MBEDTLS_SSL_TRANSPORT_STREAM,
89 MBEDTLS_SSL_PRESET_DEFAULT) != 0) {
90 goto exit;
91 }
92
93 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
94 if (options & 2) {
95 mbedtls_ssl_conf_psk(&conf, psk, sizeof(psk),
96 (const unsigned char *) psk_id, sizeof(psk_id) - 1);
97 }
98 #endif
99
100 #if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
101 if (options & 4) {
102 mbedtls_ssl_conf_ca_chain(&conf, &cacert, NULL);
103 mbedtls_ssl_conf_authmode(&conf, MBEDTLS_SSL_VERIFY_REQUIRED);
104 } else
105 #endif
106 {
107 mbedtls_ssl_conf_authmode(&conf, MBEDTLS_SSL_VERIFY_NONE);
108 }
109 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
110 mbedtls_ssl_conf_extended_master_secret(&conf,
111 (options &
112 0x10) ? MBEDTLS_SSL_EXTENDED_MS_DISABLED : MBEDTLS_SSL_EXTENDED_MS_ENABLED);
113 #endif
114 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
115 mbedtls_ssl_conf_encrypt_then_mac(&conf,
116 (options &
117 0x20) ? MBEDTLS_SSL_ETM_DISABLED : MBEDTLS_SSL_ETM_ENABLED);
118 #endif
119 #if defined(MBEDTLS_SSL_RENEGOTIATION)
120 mbedtls_ssl_conf_renegotiation(&conf,
121 (options &
122 0x80) ? MBEDTLS_SSL_RENEGOTIATION_ENABLED : MBEDTLS_SSL_RENEGOTIATION_DISABLED);
123 #endif
124 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
125 mbedtls_ssl_conf_session_tickets(&conf,
126 (options &
127 0x100) ? MBEDTLS_SSL_SESSION_TICKETS_DISABLED : MBEDTLS_SSL_SESSION_TICKETS_ENABLED);
128 #endif
129 #if defined(MBEDTLS_SSL_ALPN)
130 if (options & 0x200) {
131 mbedtls_ssl_conf_alpn_protocols(&conf, alpn_list);
132 }
133 #endif
134 //There may be other options to add :
135 // mbedtls_ssl_conf_cert_profile, mbedtls_ssl_conf_sig_hashes
136
137 srand(1);
138 mbedtls_ssl_conf_rng(&conf, dummy_random, &ctr_drbg);
139
140 if (mbedtls_ssl_setup(&ssl, &conf) != 0) {
141 goto exit;
142 }
143
144 #if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
145 if ((options & 1) == 0) {
146 if (mbedtls_ssl_set_hostname(&ssl, "localhost") != 0) {
147 goto exit;
148 }
149 }
150 #endif
151
152 biomemfuzz.Data = Data;
153 biomemfuzz.Size = Size-2;
154 biomemfuzz.Offset = 0;
155 mbedtls_ssl_set_bio(&ssl, &biomemfuzz, dummy_send, fuzz_recv, NULL);
156
157 ret = mbedtls_ssl_handshake(&ssl);
158 if (ret == 0) {
159 //keep reading data from server until the end
160 do {
161 len = sizeof(buf) - 1;
162 ret = mbedtls_ssl_read(&ssl, buf, len);
163
164 if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
165 continue;
166 } else if (ret <= 0) {
167 //EOF or error
168 break;
169 }
170 } while (1);
171 }
172
173 exit:
174 mbedtls_entropy_free(&entropy);
175 mbedtls_ctr_drbg_free(&ctr_drbg);
176 mbedtls_ssl_config_free(&conf);
177 mbedtls_ssl_free(&ssl);
178
179 #else
180 (void) Data;
181 (void) Size;
182 #endif /* MBEDTLS_SSL_CLI_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
183
184 return 0;
185 }
186