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
|
/* This example code is placed in the public domain. */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <gnutls/gnutls.h>
/* Those functions are defined in other examples.
*/
extern void check_alert(gnutls_session_t session, int ret);
extern int tcp_connect(void);
extern void tcp_close(int sd);
#define MAX_BUF 1024
#define USERNAME "user"
#define PASSWORD "pass"
#define CAFILE "/etc/ssl/certs/ca-certificates.crt"
#define MSG "GET / HTTP/1.0\r\n\r\n"
int main(void)
{
int ret;
int sd, ii;
gnutls_session_t session;
char buffer[MAX_BUF + 1];
gnutls_srp_client_credentials_t srp_cred;
gnutls_certificate_credentials_t cert_cred;
if (gnutls_check_version("3.1.4") == NULL) {
fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
exit(1);
}
/* for backwards compatibility with gnutls < 3.3.0 */
gnutls_global_init();
gnutls_srp_allocate_client_credentials(&srp_cred);
gnutls_certificate_allocate_credentials(&cert_cred);
gnutls_certificate_set_x509_trust_file(cert_cred, CAFILE,
GNUTLS_X509_FMT_PEM);
gnutls_srp_set_client_credentials(srp_cred, USERNAME, PASSWORD);
/* connects to server
*/
sd = tcp_connect();
/* Initialize TLS session
*/
gnutls_init(&session, GNUTLS_CLIENT);
/* Set the priorities.
*/
gnutls_priority_set_direct(session,
"NORMAL:+SRP:+SRP-RSA:+SRP-DSS",
NULL);
/* put the SRP credentials to the current session
*/
gnutls_credentials_set(session, GNUTLS_CRD_SRP, srp_cred);
gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, cert_cred);
gnutls_transport_set_int(session, sd);
gnutls_handshake_set_timeout(session,
GNUTLS_DEFAULT_HANDSHAKE_TIMEOUT);
/* Perform the TLS handshake
*/
do {
ret = gnutls_handshake(session);
}
while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
if (ret < 0) {
fprintf(stderr, "*** Handshake failed\n");
gnutls_perror(ret);
goto end;
} else {
char *desc;
desc = gnutls_session_get_desc(session);
printf("- Session info: %s\n", desc);
gnutls_free(desc);
}
gnutls_record_send(session, MSG, strlen(MSG));
ret = gnutls_record_recv(session, buffer, MAX_BUF);
if (gnutls_error_is_fatal(ret) != 0 || ret == 0) {
if (ret == 0) {
printf
("- Peer has closed the GnuTLS connection\n");
goto end;
} else {
fprintf(stderr, "*** Error: %s\n",
gnutls_strerror(ret));
goto end;
}
} else
check_alert(session, ret);
if (ret > 0) {
printf("- Received %d bytes: ", ret);
for (ii = 0; ii < ret; ii++) {
fputc(buffer[ii], stdout);
}
fputs("\n", stdout);
}
gnutls_bye(session, GNUTLS_SHUT_RDWR);
end:
tcp_close(sd);
gnutls_deinit(session);
gnutls_srp_free_client_credentials(srp_cred);
gnutls_certificate_free_credentials(cert_cred);
gnutls_global_deinit();
return 0;
}
|
