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; }