1#include "mbedtls/ssl.h"
2#include "mbedtls/entropy.h"
3#include "mbedtls/ctr_drbg.h"
4#include "mbedtls/ssl_ticket.h"
5#include "test/certs.h"
6#include "common.h"
7#include <string.h>
8#include <stdlib.h>
9#include <stdint.h>
10
11
12#if defined(MBEDTLS_SSL_SRV_C) && \
13    defined(MBEDTLS_ENTROPY_C) && \
14    defined(MBEDTLS_CTR_DRBG_C)
15const char *pers = "fuzz_server";
16static int initialized = 0;
17#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
18static mbedtls_x509_crt srvcert;
19static mbedtls_pk_context pkey;
20#endif
21const char *alpn_list[3];
22
23#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
24const unsigned char psk[] = {
25    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
26    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
27};
28const char psk_id[] = "Client_identity";
29#endif
30#endif // MBEDTLS_SSL_SRV_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C
31
32
33int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
34{
35#if defined(MBEDTLS_SSL_SRV_C) && \
36    defined(MBEDTLS_ENTROPY_C) && \
37    defined(MBEDTLS_CTR_DRBG_C)
38    int ret;
39    size_t len;
40    mbedtls_ssl_context ssl;
41    mbedtls_ssl_config conf;
42    mbedtls_ctr_drbg_context ctr_drbg;
43    mbedtls_entropy_context entropy;
44#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
45    mbedtls_ssl_ticket_context ticket_ctx;
46#endif
47    unsigned char buf[4096];
48    fuzzBufferOffset_t biomemfuzz;
49    uint8_t options;
50
51    //we take 1 byte as options input
52    if (Size < 1) {
53        return 0;
54    }
55    options = Data[Size - 1];
56
57    mbedtls_ctr_drbg_init(&ctr_drbg);
58    mbedtls_entropy_init(&entropy);
59#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
60    mbedtls_x509_crt_init(&srvcert);
61    mbedtls_pk_init(&pkey);
62#endif
63    mbedtls_ssl_init(&ssl);
64    mbedtls_ssl_config_init(&conf);
65#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
66    mbedtls_ssl_ticket_init(&ticket_ctx);
67#endif
68#if defined(MBEDTLS_USE_PSA_CRYPTO)
69    psa_status_t status = psa_crypto_init();
70    if (status != PSA_SUCCESS) {
71        goto exit;
72    }
73#endif /* MBEDTLS_USE_PSA_CRYPTO */
74
75    if (mbedtls_ctr_drbg_seed(&ctr_drbg, dummy_entropy, &entropy,
76                              (const unsigned char *) pers, strlen(pers)) != 0) {
77        return 1;
78    }
79
80    if (initialized == 0) {
81
82#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
83        if (mbedtls_x509_crt_parse(&srvcert, (const unsigned char *) mbedtls_test_srv_crt,
84                                   mbedtls_test_srv_crt_len) != 0) {
85            return 1;
86        }
87        if (mbedtls_x509_crt_parse(&srvcert, (const unsigned char *) mbedtls_test_cas_pem,
88                                   mbedtls_test_cas_pem_len) != 0) {
89            return 1;
90        }
91        if (mbedtls_pk_parse_key(&pkey, (const unsigned char *) mbedtls_test_srv_key,
92                                 mbedtls_test_srv_key_len, NULL, 0,
93                                 dummy_random, &ctr_drbg) != 0) {
94            return 1;
95        }
96#endif
97
98        alpn_list[0] = "HTTP";
99        alpn_list[1] = "fuzzalpn";
100        alpn_list[2] = NULL;
101
102        dummy_init();
103
104        initialized = 1;
105    }
106
107    if (mbedtls_ssl_config_defaults(&conf,
108                                    MBEDTLS_SSL_IS_SERVER,
109                                    MBEDTLS_SSL_TRANSPORT_STREAM,
110                                    MBEDTLS_SSL_PRESET_DEFAULT) != 0) {
111        goto exit;
112    }
113
114    srand(1);
115    mbedtls_ssl_conf_rng(&conf, dummy_random, &ctr_drbg);
116
117#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
118    mbedtls_ssl_conf_ca_chain(&conf, srvcert.next, NULL);
119    if (mbedtls_ssl_conf_own_cert(&conf, &srvcert, &pkey) != 0) {
120        goto exit;
121    }
122#endif
123
124    mbedtls_ssl_conf_cert_req_ca_list(&conf,
125                                      (options &
126                                       0x1) ? MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED : MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED);
127#if defined(MBEDTLS_SSL_ALPN)
128    if (options & 0x2) {
129        mbedtls_ssl_conf_alpn_protocols(&conf, alpn_list);
130    }
131#endif
132#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
133    if (options & 0x4) {
134        if (mbedtls_ssl_ticket_setup(&ticket_ctx,
135                                     dummy_random, &ctr_drbg,
136                                     MBEDTLS_CIPHER_AES_256_GCM,
137                                     86400) != 0) {
138            goto exit;
139        }
140
141        mbedtls_ssl_conf_session_tickets_cb(&conf,
142                                            mbedtls_ssl_ticket_write,
143                                            mbedtls_ssl_ticket_parse,
144                                            &ticket_ctx);
145    }
146#endif
147#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
148    mbedtls_ssl_conf_extended_master_secret(&conf,
149                                            (options &
150                                             0x10) ? MBEDTLS_SSL_EXTENDED_MS_DISABLED : MBEDTLS_SSL_EXTENDED_MS_ENABLED);
151#endif
152#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
153    mbedtls_ssl_conf_encrypt_then_mac(&conf,
154                                      (options &
155                                       0x20) ? MBEDTLS_SSL_ETM_ENABLED : MBEDTLS_SSL_ETM_DISABLED);
156#endif
157#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
158    if (options & 0x40) {
159        mbedtls_ssl_conf_psk(&conf, psk, sizeof(psk),
160                             (const unsigned char *) psk_id, sizeof(psk_id) - 1);
161    }
162#endif
163#if defined(MBEDTLS_SSL_RENEGOTIATION)
164    mbedtls_ssl_conf_renegotiation(&conf,
165                                   (options &
166                                    0x80) ? MBEDTLS_SSL_RENEGOTIATION_ENABLED : MBEDTLS_SSL_RENEGOTIATION_DISABLED);
167#endif
168
169    if (mbedtls_ssl_setup(&ssl, &conf) != 0) {
170        goto exit;
171    }
172
173    biomemfuzz.Data = Data;
174    biomemfuzz.Size = Size-1;
175    biomemfuzz.Offset = 0;
176    mbedtls_ssl_set_bio(&ssl, &biomemfuzz, dummy_send, fuzz_recv, NULL);
177
178    mbedtls_ssl_session_reset(&ssl);
179    ret = mbedtls_ssl_handshake(&ssl);
180    if (ret == 0) {
181        //keep reading data from server until the end
182        do {
183            len = sizeof(buf) - 1;
184            ret = mbedtls_ssl_read(&ssl, buf, len);
185
186            if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
187                continue;
188            } else if (ret <= 0) {
189                //EOF or error
190                break;
191            }
192        } while (1);
193    }
194
195exit:
196#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_TICKET_C)
197    mbedtls_ssl_ticket_free(&ticket_ctx);
198#endif
199    mbedtls_entropy_free(&entropy);
200    mbedtls_ctr_drbg_free(&ctr_drbg);
201    mbedtls_ssl_config_free(&conf);
202#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
203    mbedtls_x509_crt_free(&srvcert);
204    mbedtls_pk_free(&pkey);
205#endif
206    mbedtls_ssl_free(&ssl);
207#if defined(MBEDTLS_USE_PSA_CRYPTO)
208    mbedtls_psa_crypto_free();
209#endif
210#else
211    (void) Data;
212    (void) Size;
213#endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
214
215    return 0;
216}
217