#include "tlsproxy.h"
#include "connection.h"
+#include "verify.h"
/* close() */
#include <unistd.h>
#include <netdb.h>
/* poll() */
#include <poll.h>
+/* errno */
+#include <errno.h>
/* Maximum line of a HTTP request line. Longer request lines are aborted with
#define MAX_REQUEST_LINE 4096
+static int initialize_tls_session_client(int peer_socket,
+ const char *hostname,
+ gnutls_session_t *session,
+ gnutls_certificate_credentials_t *x509_cred);
+static int initialize_tls_session_server(int peer_socket,
+ gnutls_session_t *session,
+ gnutls_certificate_credentials_t *x509_cred);
+
static int read_http_request(FILE *client_fd, char *request, size_t length);
-static void send_close_bad_request(FILE *client_fd);
-static void send_close_forwarding_failure(FILE *client_fd);
+static void send_bad_request(FILE *client_fd);
+static void send_forwarding_failure(FILE *client_fd);
+static void tls_send_server_error(gnutls_session_t session);
+#if 0
static void transfer_data(int client, int server);
static int read_from_write_to(int from, int to);
+#endif
+static void transfer_data_tls(int client, int server,
+ gnutls_session_t client_session,
+ gnutls_session_t server_session);
+static int read_from_write_to_tls(gnutls_session_t from, gnutls_session_t to);
static int connect_to_host(const char *hostname, const char *port);
int version_minor;
int result;
+ /* client_x509_cred is used when talking to the client (acting as a TSL
+ * server), server_x509_cred is used when talking to the server (acting as
+ * a TSL client). */
+ gnutls_certificate_credentials_t client_x509_cred, server_x509_cred;
+
+ gnutls_session_t client_session, server_session;
+ /* initialize_tls_session_*() called? - used for goto out */
+ int client_session_init, server_session_init;
+ /* gnutls_handshake() called? - used for goto out */
+ int client_session_started, server_session_started;
+
+ LOG(LOG_DEBUG, "new connection");
+
+ server_socket = -1;
+ client_fd = NULL;
+ server_fd = NULL;
+ client_session_init = 0;
+ server_session_init = 0;
+ client_session_started = 0;
+ server_session_started = 0;
+
client_fd = fdopen(client_socket, "a+");
if (NULL == client_fd) {
- perror("fdopen()");
- close(client_socket);
- return;
+ LOG_PERROR(LOG_WARNING, "fdopen(): client failed");
+ goto out;
}
-#ifdef DEBUG
- printf("New connection:\n");
-#endif
-
/* Read request line (CONNECT ..) and headers (they are discarded). */
result = read_http_request(client_fd, buffer, sizeof(buffer));
if (-1 == result) {
- /* Read error, client_fd already closed. */
- return;
+ /* Read error. */
+ LOG(LOG_WARNING, "read_http_request(): client read error");
+ goto out;
} else if (-2 == result) {
/* EOF */
- send_close_bad_request(client_fd);
- return;
+ LOG(LOG_WARNING, "read_http_request(): client EOF");
+ send_bad_request(client_fd);
+ goto out;
}
-#ifdef DEBUG
- printf(" request: %s", buffer);
-#endif
-
if (0 != parse_request(buffer, host, port, &version_minor)) {
- send_close_bad_request(client_fd);
-#ifdef DEBUG
- printf(" bad request\n");
-#endif
- return;
+ LOG(LOG_WARNING, "bad request: %s", buffer);
+ send_bad_request(client_fd);
+ goto out;
}
-#ifdef DEBUG
- printf(" %s:%s (HTTP 1.%d)\n", host, port, version_minor);
-#endif
+ LOG(LOG_DEBUG, "target: %s:%s (HTTP 1.%d)", host, port, version_minor);
/* Connect to proxy server or directly to server. */
- if (NULL != use_proxy_host && NULL != use_proxy_port) {
- server_socket = connect_to_host(use_proxy_host, use_proxy_port);
+ if (NULL != global_proxy_host && NULL != global_proxy_port) {
+ LOG(LOG_DEBUG, "connecting to %s:%s", global_proxy_host,
+ global_proxy_port);
+ server_socket = connect_to_host(global_proxy_host, global_proxy_port);
} else {
+ LOG(LOG_DEBUG, "connecting to %s:%s", host, port);
server_socket = connect_to_host(host, port);
}
if (-1 == server_socket) {
- send_close_forwarding_failure(client_fd);
- return;
+ LOG(LOG_WARNING, "failed to connect to server");
+ send_forwarding_failure(client_fd);
+ goto out;
}
server_fd = fdopen(server_socket, "a+");
if (NULL == server_fd) {
- send_close_forwarding_failure(client_fd);
- return;
+ LOG_PERROR(LOG_WARNING, "fdopen(): server failed");
+ send_forwarding_failure(client_fd);
+ goto out;
}
/* Connect to proxy if requested (command line option). */
- if (NULL != use_proxy_host && NULL != use_proxy_port) {
+ if (NULL != global_proxy_host && NULL != global_proxy_port) {
fprintf(server_fd, "CONNECT %s:%s HTTP/1.0\r\n", host, port);
fprintf(server_fd, "\r\n");
/* Read response line from proxy server. */
result = read_http_request(server_fd, buffer, sizeof(buffer));
if (-1 == result) {
- /* Read error, server_fd already closed. */
- send_close_forwarding_failure(client_fd);
- return;
+ /* Read error. */
+ LOG(LOG_WARNING, "read_http_request(): proxy read error");
+ send_forwarding_failure(client_fd);
+ goto out;
} else if (-2 == result) {
/* EOF */
- fclose(server_fd);
- send_close_forwarding_failure(client_fd);
- return;
+ LOG(LOG_WARNING, "read_http_request(): proxy EOF");
+ send_forwarding_failure(client_fd);
+ goto out;
}
/* Check response of proxy server. */
if (0 != strncmp(buffer, "HTTP/1.0 200", 12)) {
-#ifdef DEBUG
- printf(" bad proxy response\n");
-#endif
- fclose(server_fd);
- send_close_forwarding_failure(client_fd);
- return;
+ LOG(LOG_WARNING, "bad proxy response: %s", buffer);
+ send_forwarding_failure(client_fd);
+ goto out;
}
}
-#ifdef DEBUG
- printf(" connection to server established\n");
-#endif
+ LOG(LOG_DEBUG, "connection to server established");
/* We've established a connection, tell the client. */
fprintf(client_fd, "HTTP/1.0 200 Connection established\r\n");
fprintf(client_fd, "\r\n");
fflush(client_fd);
- /* And transfer all data between client and server transparently. */
- transfer_data(client_socket, server_socket);
+ /* Initialize TLS server credentials to talk to the client. */
+ result = initialize_tls_session_client(client_socket, host,
+ &client_session,
+ &client_x509_cred);
+ if (0 != result) {
+ LOG(LOG_WARNING, "initialize_tls_session_client() failed");
+ send_forwarding_failure(client_fd);
+ goto out;
+ }
+ client_session_init = 1;
+
+ LOG(LOG_DEBUG, "starting client TLS handshake");
- fclose(client_fd);
- fclose(server_fd);
+ /* Try to establish TLS handshake between client and us. */
+ result = gnutls_handshake(client_session);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_WARNING, "client TLS handshake failed: %s",
+ gnutls_strerror(result));
+ send_forwarding_failure(client_fd);
+ goto out;
+ }
+ client_session_started = 1;
+
+ LOG(LOG_DEBUG, "client TLS handshake finished");
+
+ result = initialize_tls_session_server(server_socket, &server_session,
+ &server_x509_cred);
+ /* Initialize TLS client credentials to talk to the server. */
+ if (0 != result) {
+ LOG(LOG_WARNING, "initialize_tls_session_server() failed");
+ send_forwarding_failure(client_fd);
+ goto out;
+ }
+ server_session_init = 1;
+
+ LOG(LOG_DEBUG, "starting server TLS handshake");
+
+ /* Try to establish TLS handshake between us and server. */
+ result = gnutls_handshake(server_session);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_WARNING, "server TLS handshake failed: %s",
+ gnutls_strerror(result));
+ send_forwarding_failure(client_fd);
+ goto out;
+ }
+ server_session_started = 1;
+
+ LOG(LOG_DEBUG, "server TLS handshake finished, transferring data");
+
+ /* Make sure the server certificate is valid and known. */
+ if (0 != verify_tls_connection(server_session, host)) {
+ LOG(LOG_ERROR, "server certificate validation failed!");
+ tls_send_server_error(client_session);
+ goto out;
+ }
+
+ /* Proxy data between client and server until one suite is done (EOF or
+ * error). */
+ transfer_data_tls(client_socket, server_socket,
+ client_session, server_session);
+
+ LOG(LOG_DEBUG, "finished transferring data");
+
+out:
+ /* Close TLS sessions if necessary. Use GNUTLS_SHUT_RDWR so the data is
+ * reliable transmitted. */
+ if (0 != server_session_started) {
+ gnutls_bye(server_session, GNUTLS_SHUT_RDWR);
+ }
+ if (0 != client_session_started) {
+ gnutls_bye(client_session, GNUTLS_SHUT_RDWR);
+ }
+ if (0 != server_session_init) {
+ gnutls_deinit(server_session);
+ gnutls_certificate_free_credentials(server_x509_cred);
+ }
+ if (0 != client_session_init) {
+ gnutls_deinit(client_session);
+ gnutls_certificate_free_cas(client_x509_cred);
+ gnutls_certificate_free_keys(client_x509_cred);
+ gnutls_certificate_free_credentials(client_x509_cred);
+ }
+
+ /* Close connection to server/proxy. */
+ if (NULL != server_fd) {
+ fclose(server_fd);
+ } else if (-1 != server_socket) {
+ close(server_socket);
+ }
+ LOG(LOG_DEBUG, "connection to server closed");
+ /* Close connection to client. */
+ if (NULL != client_fd) {
+ fclose(client_fd);
+ } else {
+ close(client_socket);
+ }
+ LOG(LOG_DEBUG, "connection to client closed");
+
+ LOG(LOG_DEBUG, "connection finished");
+}
+
+
+static int initialize_tls_session_client(int peer_socket,
+ const char *hostname,
+ gnutls_session_t *session,
+ gnutls_certificate_credentials_t *x509_cred) {
+ int result;
+ char path[1024];
+
+ /* Hostname too long. */
+ if (sizeof(path) - strlen(PROXY_SERVER_CERT_FORMAT) <= strlen(hostname)) {
+ LOG(LOG_WARNING,
+ "initialize_tls_session_client(): hostname too long: '%s'",
+ hostname);
+ return -1;
+ }
+ /* Try to prevent path traversals in hostnames. */
+ if (NULL != strstr(hostname, "..")) {
+ LOG(LOG_WARNING,
+ "initialize_tls_session_client(): possible path traversal: '%s'",
+ hostname);
+ return -1;
+ }
+ snprintf(path, sizeof(path), PROXY_SERVER_CERT_FORMAT, hostname);
+
+ result = gnutls_certificate_allocate_credentials(x509_cred);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_client(): \
+gnutls_certificate_allocate_credentials(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+
+ /* Load proxy CA file, this CA "list" is send to the client. */
+ result = gnutls_certificate_set_x509_trust_file(*x509_cred,
+ PROXY_CA_FILE,
+ GNUTLS_X509_FMT_PEM);
+ if (0 >= result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_client(): can't read CA file: '%s'",
+ PROXY_CA_FILE);
+ return -1;
+ }
+ /* And certificate for this website and proxy's private key. */
+ result = gnutls_certificate_set_x509_key_file(*x509_cred,
+ path, PROXY_KEY_FILE,
+ GNUTLS_X509_FMT_PEM);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_client(): \
+can't read server certificate ('%s') or key file ('%s'): %s",
+ path, PROXY_KEY_FILE, gnutls_strerror(result));
+ /* Could be a missing certificate. */
+ return -2;
+ }
+
+ gnutls_certificate_set_dh_params(*x509_cred, tls_dh_params);
+
+ result = gnutls_init(session, GNUTLS_SERVER);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_client(): gnutls_init(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+ result = gnutls_priority_set(*session, tls_priority_cache);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_client(): gnutls_priority_set(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+ result = gnutls_credentials_set(*session,
+ GNUTLS_CRD_CERTIFICATE, *x509_cred);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_client(): gnutls_credentials_set(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+
+ gnutls_transport_set_ptr(*session, (gnutls_transport_ptr_t)peer_socket);
+
+ return 0;
}
+static int initialize_tls_session_server(int peer_socket,
+ gnutls_session_t *session,
+ gnutls_certificate_credentials_t *x509_cred) {
+ int result;
+
+ result = gnutls_certificate_allocate_credentials(x509_cred);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_server(): \
+gnutls_certificate_allocate_credentials(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+
+ result = gnutls_init(session, GNUTLS_CLIENT);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_server(): gnutls_init(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+ gnutls_priority_set(*session, tls_priority_cache);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_server(): gnutls_priority_set(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+ result = gnutls_credentials_set(*session,
+ GNUTLS_CRD_CERTIFICATE, *x509_cred);
+ if (GNUTLS_E_SUCCESS != result) {
+ LOG(LOG_ERROR,
+ "initialize_tls_session_server(): gnutls_credentials_set(): %s",
+ gnutls_strerror(result));
+ return -1;
+ }
+
+ gnutls_transport_set_ptr(*session, (gnutls_transport_ptr_t)peer_socket);
+
+ return 0;
+}
+
/* Read HTTP request line and headers (ignored).
*
- * On success 0 is returned, -1 on client error (we close client descriptor in
- * this case), -2 on unexpected EOF.
+ * On success 0 is returned, -1 on client error, -2 on unexpected EOF.
*/
static int read_http_request(FILE *client_fd, char *request, size_t length) {
char buffer[MAX_REQUEST_LINE];
if (NULL == fgets(request, (int)length, client_fd)) {
if (ferror(client_fd)) {
- perror("fgets(), request");
- fclose(client_fd);
+ LOG_PERROR(LOG_WARNING, "read_http_request(): fgets()");
return -1;
}
}
}
if (ferror(client_fd)) {
- perror("fgets(), header");
- fclose(client_fd);
+ LOG_PERROR(LOG_WARNING, "read_http_request(): fgets()");
return -1;
}
return 0;
}
-static void send_close_bad_request(FILE *client_fd) {
+static void send_bad_request(FILE *client_fd) {
fprintf(client_fd, "HTTP/1.0 400 Bad Request\r\n");
fprintf(client_fd, "\r\n");
- fclose(client_fd);
}
-static void send_close_forwarding_failure(FILE *client_fd) {
+static void send_forwarding_failure(FILE *client_fd) {
fprintf(client_fd, "HTTP/1.0 503 Forwarding failure\r\n");
fprintf(client_fd, "\r\n");
- fclose(client_fd);
+}
+static void tls_send_server_error(gnutls_session_t session) {
+ gnutls_record_send(session, "HTTP/1.0 500 Internal Server Error\r\n", 36);
+ gnutls_record_send(session, "\r\n", 2);
}
+#if 0
/* Transfer data between client and server sockets until one closes the
* connection. */
static void transfer_data(int client, int server) {
for (;;) {
int result = poll(fds, 2, -1 /* no timeout */);
if (result < 0) {
- perror("poll()");
+ LOG_PERROR(LOG_ERROR, "transfer_data(): poll()");
return;
}
size_read = read(from, buffer, sizeof(buffer));
if (0 > size_read) {
- perror("read()");
+ LOG_PERROR(LOG_WARNING, "read_from_write_to(): read()");
return -1;
}
/* EOF */
size_written = write(to, buffer, (size_t)size_read);
if (0 > size_written) {
- perror("write()");
+ LOG_PERROR(LOG_WARNING, "read_from_write_to(): write()");
+ return -1;
+ }
+ if (size_read != size_written) {
+ LOG(LOG_ERROR, "read_from_write_to(): only written %ld of %ld bytes!",
+ (long int)size_written, (long int)size_read);
+ return -1;
+ }
+
+ return 0;
+}
+#endif
+
+/* Transfer data between client and server TLS connection until one closes the
+ * connection. */
+static void transfer_data_tls(int client, int server,
+ gnutls_session_t client_session,
+ gnutls_session_t server_session) {
+ struct pollfd fds[2];
+ fds[0].fd = client;
+ fds[0].events = POLLIN | POLLPRI | POLLHUP | POLLERR;
+ fds[0].revents = 0;
+ fds[1].fd = server;
+ fds[1].events = POLLIN | POLLPRI | POLLHUP | POLLERR;
+ fds[1].revents = 0;
+
+ for (;;) {
+ int result = poll(fds, 2, -1 /* no timeout */);
+ if (result < 0) {
+ LOG_PERROR(LOG_ERROR, "transfer_data(): poll()");
+ return;
+ }
+
+ /* Data available from client. */
+ if (fds[0].revents & POLLIN || fds[0].revents & POLLPRI) {
+ if (0 != read_from_write_to_tls(client_session, server_session)) {
+ /* EOF (or other error) */
+ break;
+ }
+ }
+ /* Data available from server. */
+ if (fds[1].revents & POLLIN || fds[1].revents & POLLPRI) {
+ if (0 != read_from_write_to_tls(server_session, client_session)) {
+ /* EOF (or other error) */
+ break;
+ }
+ }
+
+ /* Client closed connection. */
+ if (fds[0].revents & POLLERR || fds[0].revents & POLLHUP) {
+ break;
+ }
+ /* Server closed connection. */
+ if (fds[1].revents & POLLERR || fds[1].revents & POLLHUP) {
+ break;
+ }
+ }
+}
+
+/* Read available data from session from and write to session to. */
+static int read_from_write_to_tls(gnutls_session_t from,
+ gnutls_session_t to) {
+ size_t size;
+ ssize_t size_read;
+ ssize_t size_written;
+ char buffer[16384];
+
+ /* Get maximum possible buffer size. */
+ size = gnutls_record_get_max_size(from);
+ LOG(LOG_DEBUG, "read_from_write_to_tls(): suggested buffer size: %ld",
+ (long int)size);
+ if (size > gnutls_record_get_max_size(to)) {
+ size = gnutls_record_get_max_size(to);
+ }
+ if (size > sizeof(buffer)) {
+ size = sizeof(buffer);
+ }
+ LOG(LOG_DEBUG, "read_from_write_to_tls(): used buffer size: %ld",
+ (long int)size);
+
+ size_read = gnutls_record_recv(from, buffer, size);
+ if (0 > size_read) {
+ LOG(LOG_WARNING, "read_from_write_to_tls(): gnutls_record_recv(): %s",
+ gnutls_strerror((int)size_read));
+ return -1;
+ }
+ /* EOF */
+ if (0 == size_read) {
+ return -1;
+ }
+
+ size_written = gnutls_record_send(to, buffer, (size_t)size_read);
+ if (0 > size_written) {
+ LOG(LOG_WARNING, "read_from_write_to_tls(): gnutls_record_send(): %s",
+ gnutls_strerror((int)size_written));
return -1;
}
if (size_read != size_written) {
- printf("only written %ld of %ld bytes!\n", (long int)size_read,
- (long int)size_written);
+ LOG(LOG_ERROR, "read_from_write_to_tls(): only written %ld of %ld bytes!",
+ (long int)size_written, (long int)size_read);
return -1;
}
| AI_V4MAPPED; /* support IPv4 through IPv6 */
gai_return = getaddrinfo(hostname, port, &gai_hints, &gai_result);
if (0 != gai_return) {
- perror("getaddrinfo()");
+ LOG_PERROR(LOG_WARNING, "connect_to_host(): getaddrinfo()");
return -1;
}
server->ai_socktype,
server->ai_protocol);
if (-1 == server_socket) {
- perror("socket(), trying next");
+ LOG_PERROR(LOG_DEBUG, "connect_to_host(): socket(), trying next");
continue;
}
server->ai_addrlen)) {
break;
}
- perror("connect(), trying next");
+ LOG_PERROR(LOG_DEBUG, "connect_to_host(): connect(), trying next");
close(server_socket);
}
freeaddrinfo(gai_result);
if (NULL == server) {
- fprintf(stderr, "no server found, aborting\n");
+ LOG_PERROR(LOG_WARNING, "connect_to_host(): no server found, abort");
return -1;
}
ruderich.org/simon / tlsproxy / tlsproxy.git / blobdiff