/* client-tls-callback.c
*
* Copyright (C) 2006-2015 wolfSSL Inc.
*
* This file is part of wolfSSL. (formerly known as CyaSSL)
*
* wolfSSL is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* wolfSSL is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
/* the usual suspects */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
/* socket includes */
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <unistd.h>
/* wolfSSL */
#include <wolfssl/options.h>
#include <wolfssl/ssl.h>
#define DEFAULT_PORT 11111
#define CERT_FILE "../certs/ca-cert.pem"


int my_IORecv(WOLFSSL* ssl, char* buff, int sz, void* ctx)
{
/* By default, ctx will be a pointer to the file descriptor to read from.
* This can be changed by calling wolfSSL_SetIOReadCtx(). */
int sockfd = *(int*)ctx;
int recvd;
/* Receive message from socket */
if ((recvd = recv(sockfd, buff, sz, 0)) == -1) {
/* error encountered. Be responsible and report it in wolfSSL terms */
fprintf(stderr, "IO RECEIVE ERROR: ");
switch (errno) {
#if EAGAIN != EWOULDBLOCK
case EAGAIN: /* EAGAIN == EWOULDBLOCK on some systems, but not others */
#endif
case EWOULDBLOCK:
if (!wolfSSL_dtls(ssl) || wolfSSL_get_using_nonblock(ssl)) {
fprintf(stderr, "would block\n");
return WOLFSSL_CBIO_ERR_WANT_READ;
}
else {
fprintf(stderr, "socket timeout\n");
return WOLFSSL_CBIO_ERR_TIMEOUT;
}
case ECONNRESET:
fprintf(stderr, "connection reset\n");
return WOLFSSL_CBIO_ERR_CONN_RST;
case EINTR:
fprintf(stderr, "socket interrupted\n");
return WOLFSSL_CBIO_ERR_ISR;
case ECONNREFUSED:
fprintf(stderr, "connection refused\n");
return WOLFSSL_CBIO_ERR_WANT_READ;
case ECONNABORTED:
fprintf(stderr, "connection aborted\n");
return WOLFSSL_CBIO_ERR_CONN_CLOSE;
default:
fprintf(stderr, "general error\n");
return WOLFSSL_CBIO_ERR_GENERAL;
}
}
else if (recvd == 0) {
printf("Connection closed\n");
return WOLFSSL_CBIO_ERR_CONN_CLOSE;
}
/* successful receive */
printf("my_IORecv: received %d bytes from %d\n", sz, sockfd);
return recvd;
}


int my_IOSend(WOLFSSL* ssl, char* buff, int sz, void* ctx)
{
/* By default, ctx will be a pointer to the file descriptor to write to.
* This can be changed by calling wolfSSL_SetIOWriteCtx(). */
int sockfd = *(int*)ctx;
int sent;
/* Receive message from socket */
if ((sent = send(sockfd, buff, sz, 0)) == -1) {
/* error encountered. Be responsible and report it in wolfSSL terms */
fprintf(stderr, "IO SEND ERROR: ");
switch (errno) {
#if EAGAIN != EWOULDBLOCK
case EAGAIN: /* EAGAIN == EWOULDBLOCK on some systems, but not others */
#endif
case EWOULDBLOCK:
fprintf(stderr, "would block\n");
return WOLFSSL_CBIO_ERR_WANT_READ;
case ECONNRESET:
fprintf(stderr, "connection reset\n");
return WOLFSSL_CBIO_ERR_CONN_RST;
case EINTR:
fprintf(stderr, "socket interrupted\n");
return WOLFSSL_CBIO_ERR_ISR;
case EPIPE:
fprintf(stderr, "socket EPIPE\n");
return WOLFSSL_CBIO_ERR_CONN_CLOSE;
default:
fprintf(stderr, "general error\n");
return WOLFSSL_CBIO_ERR_GENERAL;
}
}
else if (sent == 0) {
printf("Connection closed\n");
return 0;
}
/* successful send */
printf("my_IOSend: sent %d bytes to %d\n", sz, sockfd);
return sent;
}



int main(int argc, char** argv)
{
int sockfd;
struct sockaddr_in servAddr;
char buff[256];
size_t len;
/* declare wolfSSL objects */
WOLFSSL_CTX* ctx;
WOLFSSL* ssl;
/* Check for proper calling convention */
if (argc != 2) {
printf("usage: %s <IPv4 address>\n", argv[0]);
return 0;
}
/* Initialize wolfSSL */
wolfSSL_Init();
/* Create a socket that uses an internet IPv4 address,
* Sets the socket to be stream based (TCP),
* 0 means choose the default protocol. */
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
fprintf(stderr, "ERROR: failed to create the socket\n");
return -1;
}
/* Create and initialize WOLFSSL_CTX */
if ((ctx = wolfSSL_CTX_new(wolfTLSv1_2_client_method())) == NULL) {
fprintf(stderr, "ERROR: failed to create WOLFSSL_CTX\n");
return -1;
}
/* Load client certificates into WOLFSSL_CTX */
if (wolfSSL_CTX_load_verify_locations(ctx, CERT_FILE, NULL)
!= SSL_SUCCESS) {
fprintf(stderr, "ERROR: failed to load %s, please check the file.\n",
CERT_FILE);
return -1;
}
/* Register callbacks */
wolfSSL_SetIORecv(ctx, my_IORecv);
wolfSSL_SetIOSend(ctx, my_IOSend);
/* Initialize the server address struct with zeros */
memset(&servAddr, 0, sizeof(servAddr));
/* Fill in the server address */
servAddr.sin_family = AF_INET; /* using IPv4 */
servAddr.sin_port = htons(DEFAULT_PORT); /* on DEFAULT_PORT */
/* Get the server IPv4 address from the command line call */
if (inet_pton(AF_INET, argv[1], &servAddr.sin_addr) != 1) {
fprintf(stderr, "ERROR: invalid address\n");
return -1;
}
/* Connect to the server */
if (connect(sockfd, (struct sockaddr*) &servAddr, sizeof(servAddr))
== -1) {
fprintf(stderr, "ERROR: failed to connect\n");
return -1;
}
/* Create a WOLFSSL object */
if ((ssl = wolfSSL_new(ctx)) == NULL) {
fprintf(stderr, "ERROR: failed to create WOLFSSL object\n");
return -1;
}
/* Attach wolfSSL to the socket */
wolfSSL_set_fd(ssl, sockfd);
/* Connect to wolfSSL on the server side */
if (wolfSSL_connect(ssl) != SSL_SUCCESS) {
fprintf(stderr, "ERROR: failed to connect to wolfSSL\n");
return -1;
}
/* Get a message for the server from stdin */
printf("Message for server: ");
memset(buff, 0, sizeof(buff));
fgets(buff, sizeof(buff), stdin);
len = strnlen(buff, sizeof(buff));
/* Send the message to the server */
if (wolfSSL_write(ssl, buff, len) != len) {
fprintf(stderr, "ERROR: failed to write\n");
return -1;
}
/* Read the server data into our buff array */
memset(buff, 0, sizeof(buff));
if (wolfSSL_read(ssl, buff, sizeof(buff)-1) == -1) {
fprintf(stderr, "ERROR: failed to read\n");
return -1;
}
/* Print to stdout any data the server sends */
printf("Server: %s\n", buff);
/* Cleanup and return */
wolfSSL_free(ssl); /* Free the wolfSSL object */
wolfSSL_CTX_free(ctx); /* Free the wolfSSL context object */
wolfSSL_Cleanup(); /* Cleanup the wolfSSL environment */
close(sockfd); /* Close the connection to the server */
return 0; /* Return reporting a success */

