int main(int argc, char **argv)
{
if(argc != 2)
{
fprintf(stderr,"usage: %s hostname\n", argv[0]);
return 1;
}
signal(SIGINT, sigint_handler);
printf("Looking up addresses for %s ...\n", argv[1]);
struct addrinfo hints;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC; // AF_INET or AF_INET6 to force version
hints.ai_socktype = SOCK_STREAM;
struct addrinfo *dnsres;
int status_1 = getaddrinfo(argv[1], PORT, &hints, &dnsres);
if(status_1 != 0)
{
fprintf(stderr, "dns lookup failed: %s\n", gai_strerror(status_1));
return 2;
}
print_addrinfo(dnsres);
printf("Connecting to %s ...\n", "the server");
int sockfd = socket(dnsres->ai_family, dnsres->ai_socktype, dnsres->ai_protocol);
if(connect(sockfd, dnsres->ai_addr, dnsres->ai_addrlen) != 0)
{
perror("connect");
return 3;
}
printf("Connected.\n");
freeaddrinfo(dnsres); // frees the memory that was dynamically allocated for the linked lists by getaddrinfo
s2n_init();
struct s2n_config *config = s2n_config_new();
s2n_status_request_type type = S2N_STATUS_REQUEST_NONE;
s2n_config_set_status_request_type(config, type);
struct s2n_connection *conn = s2n_connection_new(S2N_CLIENT);
s2n_connection_set_config(conn, config);
s2n_connection_set_fd(conn, sockfd);
s2n_blocked_status blocked;
do {
if (s2n_negotiate(conn, &blocked) < 0) {
fprintf(stderr, "Failed to negotiate: '%s' %d\n", s2n_strerror(s2n_errno, "EN"), s2n_connection_get_alert(conn));
exit(1);
}
} while (blocked);
int client_hello_version;
int client_protocol_version;
int server_protocol_version;
int actual_protocol_version;
if ((client_hello_version = s2n_connection_get_client_hello_version(conn)) < 0) {
fprintf(stderr, "Could not get client hello version\n");
exit(1);
}
if ((client_protocol_version = s2n_connection_get_client_protocol_version(conn)) < 0) {
fprintf(stderr, "Could not get client protocol version\n");
exit(1);
}
if ((server_protocol_version = s2n_connection_get_server_protocol_version(conn)) < 0) {
fprintf(stderr, "Could not get server protocol version\n");
exit(1);
}
if ((actual_protocol_version = s2n_connection_get_actual_protocol_version(conn)) < 0) {
fprintf(stderr, "Could not get actual protocol version\n");
exit(1);
}
printf("Client hello version: %d\n", client_hello_version);
printf("Client protocol version: %d\n", client_protocol_version);
printf("Server protocol version: %d\n", server_protocol_version);
printf("Actual protocol version: %d\n", actual_protocol_version);
if (s2n_get_server_name(conn)) {
printf("Server name: %s\n", s2n_get_server_name(conn));
}
if (s2n_get_application_protocol(conn)) {
printf("Application protocol: %s\n", s2n_get_application_protocol(conn));
}
uint32_t length;
const uint8_t *status = s2n_connection_get_ocsp_response(conn, &length);
if (status && length > 0) {
fprintf(stderr, "OCSP response received, length %d\n", length);
}
printf("Cipher negotiated: %s\n", s2n_connection_get_cipher(conn));
char buf[BUFFERSIZE + 1];
int bytes_read, bytes_written;
// Make sure stdin is a terminal.
if (!isatty(STDIN_FILENO))
{
fprintf(stderr, "Not a terminal.\n");
exit(EXIT_FAILURE);
}
// Save the terminal attributes so we can restore them later.
tcgetattr(STDIN_FILENO, &saved_attributes);
atexit(reset_input_mode);
// Set the funny terminal modes.
struct termios tattr;
tcgetattr(STDIN_FILENO, &tattr);
tattr.c_lflag &= ~(ICANON | ECHO); // Clear ICANON and ECHO.
tattr.c_cc[VMIN] = 1;
tattr.c_cc[VTIME] = 0;
tcsetattr(STDIN_FILENO, TCSAFLUSH, &tattr);
fd_set master, readfds;
FD_ZERO(&master);
FD_SET(STDIN_FILENO, &master);
FD_SET(sockfd, &master);
for(;;)
{
readfds = master;
select(sockfd + 1, &readfds, NULL, NULL, NULL);
if(FD_ISSET(STDIN_FILENO, &readfds))
{
bytes_read = read(STDIN_FILENO, buf, BUFFERSIZE);
if(bytes_read < 1) break;
char *buf_ptr = buf;
int bytes_available = bytes_read;
do
{
bytes_written = s2n_send(conn, buf_ptr, bytes_available, &blocked);
if(bytes_written < 0) break;
bytes_available -= bytes_written;
buf_ptr += bytes_written;
} while(bytes_available || blocked);
}
if(FD_ISSET(sockfd, &readfds))
{
do
{
bytes_read = s2n_recv(conn, buf, BUFFERSIZE, &blocked);
if(bytes_read < 1) break;
write(STDOUT_FILENO, buf, bytes_read);
} while(blocked);
}
//if(nbytes != mbytes) printf("nbytes [%d] != mbytes [%d] \n", nbytes, mbytes);
}
close(sockfd);
s2n_connection_free(conn);
s2n_config_free(config);
s2n_cleanup();
printf("\nBYE!\n");
return 0;
}
int negotiate(struct s2n_connection *conn)
{
s2n_blocked_status blocked;
do {
if (s2n_negotiate(conn, &blocked) < 0) {
fprintf(stderr, "Failed to negotiate: '%s'. %s\n", s2n_strerror(s2n_errno, "EN"), s2n_strerror_debug(s2n_errno, "EN"));
fprintf(stderr, "Alert: %d\n", s2n_connection_get_alert(conn));
return -1;
}
} while (blocked);
/* Now that we've negotiated, print some parameters */
int client_hello_version;
int client_protocol_version;
int server_protocol_version;
int actual_protocol_version;
if ((client_hello_version = s2n_connection_get_client_hello_version(conn)) < 0) {
fprintf(stderr, "Could not get client hello version\n");
return -1;
}
if ((client_protocol_version = s2n_connection_get_client_protocol_version(conn)) < 0) {
fprintf(stderr, "Could not get client protocol version\n");
return -1;
}
if ((server_protocol_version = s2n_connection_get_server_protocol_version(conn)) < 0) {
fprintf(stderr, "Could not get server protocol version\n");
return -1;
}
if ((actual_protocol_version = s2n_connection_get_actual_protocol_version(conn)) < 0) {
fprintf(stderr, "Could not get actual protocol version\n");
return -1;
}
printf("CONNECTED:\n");
printf("Client hello version: %d\n", client_hello_version);
printf("Client protocol version: %d\n", client_protocol_version);
printf("Server protocol version: %d\n", server_protocol_version);
printf("Actual protocol version: %d\n", actual_protocol_version);
if (s2n_get_server_name(conn)) {
printf("Server name: %s\n", s2n_get_server_name(conn));
}
if (s2n_get_application_protocol(conn)) {
printf("Application protocol: %s\n", s2n_get_application_protocol(conn));
}
printf("Curve: %s\n", s2n_connection_get_curve(conn));
uint32_t length;
const uint8_t *status = s2n_connection_get_ocsp_response(conn, &length);
if (status && length > 0) {
fprintf(stderr, "OCSP response received, length %u\n", length);
}
printf("Cipher negotiated: %s\n", s2n_connection_get_cipher(conn));
if (s2n_connection_is_session_resumed(conn)) {
printf("Resumed session\n");
}
return 0;
}
