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/************************
* sslconnect 0.2
* Last Change: 2013-06-17
* C Implementation by Simon Rettberg
* Original sslconnect 0.1 was written in perl by Martin Walter
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <netdb.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <openssl/bio.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
/* Init libs and data strctures */
void init();
/* print error report of something failed */
void ssl_error();
/* connect via ssl */
SSL* ssl_connect(char * host, uint16_t port, uint16_t local_port, SSL_CTX ** ctx);
/* read from ssl connection */
ssize_t ssl_read(SSL * bio, char * buffer, ssize_t length);
/* write to ssl connection */
int ssl_write(SSL * bio, char * buffer, ssize_t length);
int main(int argc, char ** argv);
void init()
{
SSL_load_error_strings();
SSL_library_init();
OpenSSL_add_all_algorithms();
}
void ssl_error(char* message)
{
fprintf(stderr, message);
fprintf(stderr, "\n%s\n", ERR_error_string(ERR_get_error(), NULL));
fprintf(stderr, "Details: %s\n", ERR_reason_error_string(ERR_get_error()));
ERR_print_errors_fp(stderr);
}
SSL* ssl_connect(char * host, uint16_t port, uint16_t local_port, SSL_CTX ** ctx)
{
int ret = 0;
/* create socket. needs to be done manually in order to bind to local port */
int fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
fprintf(stderr, "Could not create socket.\n");
return NULL;
}
struct sockaddr_in sa_dest, sa_local;
memset(&sa_local, 0, sizeof(sa_local));
memset(&sa_dest, 0, sizeof(sa_dest));
sa_local.sin_family = AF_INET;
sa_local.sin_port = htons(local_port);
ret = bind(fd, (struct sockaddr *)&sa_local, sizeof(struct sockaddr));
if (ret == -1) {
fprintf(stderr, "Could not bind local socket to 0.0.0.0:%d (%d)\n", (int)local_port, (int)errno);
close(fd);
return NULL;
}
sa_dest.sin_family = AF_INET;
sa_dest.sin_port = htons(port);
struct hostent * rec;
rec = gethostbyname(host);
if (rec == NULL) {
fprintf(stderr, "Error: Invalid host: %s\n", host);
return NULL;
}
memcpy(&(sa_dest.sin_addr), rec->h_addr, sizeof(struct in_addr));
ret = connect(fd, (struct sockaddr *)&sa_dest, sizeof(struct sockaddr));
if (ret == -1) {
fprintf(stderr, "Could not connect to %s:%d (%d)\n", host, (int)port, (int)errno);
close(fd);
return NULL;
}
/* openssl part */
SSL * ssl;
/* Set up the SSL pointers */
*ctx = SSL_CTX_new(SSLv23_client_method());
ssl = SSL_new(*ctx);
SSL_set_fd(ssl, fd);
ret = SSL_connect(ssl);
if (ret <= 0) {
ssl_error("Unable to SSL_connect");
return NULL;
}
SSL_set_mode(ssl, SSL_MODE_AUTO_RETRY);
return ssl;
}
ssize_t ssl_read(SSL * ssl, char * buffer, ssize_t length)
{
ssize_t ret = -1;
int retries = 10;
while (ret < 0 && --retries > 0) {
ret = SSL_read(ssl, buffer, length);
if (ret >= 0) {
return ret;
}
ssl_error("SSL_read failed");
return -1;
}
return -1;
}
int ssl_write(SSL * ssl, char * buffer, ssize_t length)
{
ssize_t ret = -1;
int retries = 10;
while (ret < 0 && --retries > 0) {
ret = SSL_write(ssl, buffer, length);
if (ret >= 0) {
return ret;
}
ssl_error("SSL_write failed");
return -1;
}
return -1;
}
#define READBUF 5000
int main(int argc, char ** argv)
{
if (argc < 2) {
fprintf(stderr, "Usage: %s host:port\n", argv[0]);
return 1;
}
init();
char buffer[READBUF];
SSL_CTX * ctx = NULL;
SSL * ssl;
ssize_t len;
size_t ret;
char * pos;
int port, lport;
pos = strchr(argv[1], ':');
if (pos == NULL) {
fprintf(stderr, "Error: No Port given.\n");
return 5;
}
port = atoi(pos+1);
*pos = '\0';
lport = rand() % 800 + 95;
ssl = ssl_connect(argv[1], (uint16_t)port, (uint16_t)lport, &ctx);
if (ssl == NULL) {
return 2;
}
ssl_write(ssl, "", 0);
for (;;) {
len = ssl_read(ssl, buffer, READBUF);
if (len <= 0) {
break;
}
ret = fwrite(buffer, 1, len, stdout);
if (ret != len) {
fprintf(stderr, "Error: fwrite could not write all received data to stdout.\n");
return 3;
}
}
if (len < 0) {
return 4;
}
return 0;
}
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