#include "connection.h"
#include "verify.h"
+#include <assert.h>
#include <errno.h>
#include <netdb.h>
#include <poll.h>
/* Format string used to send HTTP/1.0 error responses to the client.
*
- * %s is used 4 times, first three are the error code (no %n$s!), the last is
- * the message. */
+ * %s is used 5 times, first is the error code, then additional headers, next
+ * two are the error code (no %n$s!), the last is the message. */
#define HTTP_RESPONSE_FORMAT "HTTP/1.0 %s\r\n\
Content-Type: text/html; charset=US-ASCII\r\n\
-\r\n\
+%s\r\n\
<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">\n\
<html>\n\
<head><title>%s</title></head>\n\
gnutls_session_t *session,
gnutls_certificate_credentials_t *x509_cred);
+static int fdopen_read_write(int socket, FILE **read_fd, FILE **write_fd);
static int read_http_request(FILE *client_fd, char *request, size_t length);
static void send_bad_request(FILE *client_fd);
static void send_forwarding_failure(FILE *client_fd);
void handle_connection(int client_socket) {
int server_socket;
- FILE *client_fd, *server_fd;
+ FILE *client_fd_read, *client_fd_write, *server_fd_read, *server_fd_write;
char buffer[MAX_REQUEST_LINE];
char host[MAX_REQUEST_LINE];
char port[5 + 1];
- int version_minor; /* HTTP/1.x */
+ int version_minor; /* x in HTTP/1.x */
int result;
/* client_x509_cred is used when talking to the client (acting as a TSL
* certificate. */
int validation_failed;
- LOG(LOG_DEBUG, "new connection");
+ LOG(DEBUG, "new connection");
server_socket = -1;
- client_fd = NULL;
- server_fd = NULL;
+ client_fd_read = NULL;
+ client_fd_write = NULL;
+ server_fd_read = NULL;
+ server_fd_write = NULL;
client_session_init = 0;
server_session_init = 0;
client_session_started = 0;
server_session_started = 0;
validation_failed = 0;
- client_fd = fdopen(client_socket, "a+");
- if (client_fd == NULL) {
- LOG_PERROR(LOG_WARNING, "fdopen(): client failed");
+ if (fdopen_read_write(client_socket, &client_fd_read,
+ &client_fd_write) != 0) {
goto out;
}
/* Read request line (CONNECT ..) and headers (they are discarded). */
- result = read_http_request(client_fd, buffer, sizeof(buffer));
+ result = read_http_request(client_fd_read, buffer, sizeof(buffer));
if (result == -1) {
- /* Read error. */
- LOG(LOG_WARNING, "read_http_request(): client read error");
+ LOG(WARNING, "read_http_request(): client read error");
goto out;
} else if (result == -2) {
- /* EOF */
- LOG(LOG_WARNING, "read_http_request(): client EOF");
- send_bad_request(client_fd);
+ LOG(WARNING, "read_http_request(): client EOF");
+ send_bad_request(client_fd_write);
goto out;
}
if (parse_request(buffer, host, port, &version_minor) != 0) {
- LOG(LOG_WARNING, "bad request: %s", buffer);
- send_bad_request(client_fd);
+ LOG(WARNING, "bad request: %s", buffer);
+ send_bad_request(client_fd_write);
goto out;
}
- LOG(LOG_DEBUG, "target: %s:%s (HTTP 1.%d)", host, port, version_minor);
+ LOG(DEBUG, "target: %s:%s (HTTP 1.%d)", host, port, version_minor);
/* Connect to proxy server or directly to server. */
if (global_proxy_host != NULL && global_proxy_port != NULL) {
- LOG(LOG_DEBUG, "connecting to %s:%s", global_proxy_host,
+ 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);
+ LOG(DEBUG, "connecting to %s:%s", host, port);
server_socket = connect_to_host(host, port);
}
if (server_socket == -1) {
- LOG(LOG_WARNING, "failed to connect to server");
- send_forwarding_failure(client_fd);
+ LOG(WARNING, "failed to connect to server");
+ send_forwarding_failure(client_fd_write);
goto out;
}
- server_fd = fdopen(server_socket, "a+");
- if (server_fd == NULL) {
- LOG_PERROR(LOG_WARNING, "fdopen(): server failed");
- send_forwarding_failure(client_fd);
+ if (fdopen_read_write(server_socket, &server_fd_read,
+ &server_fd_write) != 0) {
+ send_forwarding_failure(client_fd_write);
goto out;
}
/* Connect to proxy if requested (command line option). */
if (global_proxy_host != NULL && global_proxy_port != NULL) {
- fprintf(server_fd, "CONNECT %s:%s HTTP/1.0\r\n", host, port);
- fprintf(server_fd, "\r\n");
+ fprintf(server_fd_write, "CONNECT %s:%s HTTP/1.0\r\n", host, port);
+ fprintf(server_fd_write, "\r\n");
+ fflush(server_fd_write);
/* Read response line from proxy server. */
- result = read_http_request(server_fd, buffer, sizeof(buffer));
+ result = read_http_request(server_fd_read, buffer, sizeof(buffer));
if (result == -1) {
- /* Read error. */
- LOG(LOG_WARNING, "read_http_request(): proxy read error");
- send_forwarding_failure(client_fd);
+ LOG(WARNING, "read_http_request(): proxy read error");
+ send_forwarding_failure(client_fd_write);
goto out;
} else if (result == -2) {
- /* EOF */
- LOG(LOG_WARNING, "read_http_request(): proxy EOF");
- send_forwarding_failure(client_fd);
+ LOG(WARNING, "read_http_request(): proxy EOF");
+ send_forwarding_failure(client_fd_write);
goto out;
}
/* Check response of proxy server. */
if (strncmp(buffer, "HTTP/1.0 200", 12)) {
- LOG(LOG_WARNING, "bad proxy response: %s", buffer);
- send_forwarding_failure(client_fd);
+ LOG(WARNING, "bad proxy response: %s", buffer);
+ send_forwarding_failure(client_fd_write);
goto out;
}
}
- LOG(LOG_DEBUG, "connection to server established");
+ LOG(DEBUG, "connection to server established");
/* If the -u option is used and we don't know this hostname's server
* certificate then just pass through the connection and let the client
if (server_certificate_file(&file, host, path, sizeof(path)) == -2) {
/* 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);
+ fprintf(client_fd_write, "HTTP/1.0 200 Connection established\r\n");
+ fprintf(client_fd_write, "\r\n");
+ fflush(client_fd_write);
- LOG(LOG_DEBUG, "transferring data");
+ LOG(DEBUG, "transferring data");
/* Proxy data between client and server until one side is done
* (EOF or error). */
transfer_data(client_socket, server_socket);
- LOG(LOG_DEBUG, "finished transferring data");
+ LOG(DEBUG, "finished transferring data");
goto out;
}
result = initialize_tls_session_server(server_socket, &server_session,
&server_x509_cred);
if (result != 0) {
- LOG(LOG_WARNING, "initialize_tls_session_server() failed");
- send_forwarding_failure(client_fd);
+ LOG(WARNING, "initialize_tls_session_server() failed");
+ send_forwarding_failure(client_fd_write);
goto out;
}
server_session_init = 1;
- LOG(LOG_DEBUG, "starting server TLS handshake");
+ LOG(DEBUG, "starting server TLS handshake");
/* Try to establish TLS handshake between us and server. */
result = gnutls_handshake(server_session);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_WARNING, "server TLS handshake failed: %s",
+ LOG(WARNING, "server TLS handshake failed: %s",
gnutls_strerror(result));
- send_forwarding_failure(client_fd);
+ send_forwarding_failure(client_fd_write);
goto out;
}
server_session_started = 1;
- LOG(LOG_DEBUG, "server TLS handshake finished");
+ LOG(DEBUG, "server TLS handshake finished");
/* Make sure the server certificate is valid and known. */
if (verify_tls_connection(server_session, host) != 0) {
- LOG(LOG_ERROR, "server certificate validation failed!");
- /* We send the error message over our TLS connection to the client,
+ LOG(ERROR, "server certificate validation failed!");
+ /* We'll send the error message over our TLS connection to the client,
* but with an invalid certificate. No data is transfered from/to the
* target server. */
validation_failed = 1;
&client_session,
&client_x509_cred);
if (result != 0) {
- LOG(LOG_WARNING, "initialize_tls_session_client() failed");
- send_forwarding_failure(client_fd);
+ LOG(WARNING, "initialize_tls_session_client() failed");
+ send_forwarding_failure(client_fd_write);
goto out;
}
client_session_init = 1;
/* 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);
+ fprintf(client_fd_write, "HTTP/1.0 200 Connection established\r\n");
+ fprintf(client_fd_write, "\r\n");
+ fflush(client_fd_write);
- LOG(LOG_DEBUG, "starting client TLS handshake");
+ LOG(DEBUG, "starting client TLS handshake");
/* Try to establish TLS handshake between client and us. */
result = gnutls_handshake(client_session);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_WARNING, "client TLS handshake failed: %s",
+ LOG(WARNING, "client TLS handshake failed: %s",
gnutls_strerror(result));
- send_forwarding_failure(client_fd);
+ send_forwarding_failure(client_fd_write);
goto out;
}
client_session_started = 1;
- LOG(LOG_DEBUG, "client TLS handshake finished");
+ LOG(DEBUG, "client TLS handshake finished");
/* Tell the client that the verification failed. Shouldn't be necessary as
* the client should terminate the connection because he received the
goto out;
}
- LOG(LOG_DEBUG, "transferring TLS data");
+ LOG(DEBUG, "transferring TLS data");
/* Proxy data between client and server until one side is done (EOF or
* error). */
transfer_data_tls(client_socket, server_socket,
client_session, server_session);
- LOG(LOG_DEBUG, "finished transferring TLS data");
+ LOG(DEBUG, "finished transferring TLS data");
out:
/* Close TLS sessions if necessary. Use GNUTLS_SHUT_RDWR so the data is
}
/* Close connection to server/proxy. */
- if (server_fd != NULL) {
- fclose(server_fd);
+ if (server_fd_read != NULL) {
+ if (server_fd_write != NULL) {
+ fclose(server_fd_write);
+ }
+ fclose(server_fd_read);
} else if (server_socket != -1) {
close(server_socket);
}
- LOG(LOG_DEBUG, "connection to server closed");
+ LOG(DEBUG, "connection to server closed");
/* Close connection to client. */
- if (client_fd != NULL) {
- fclose(client_fd);
+ if (client_fd_read != NULL) {
+ if (client_fd_write != NULL) {
+ fclose(client_fd_write);
+ }
+ fclose(client_fd_read);
} else {
close(client_socket);
}
- LOG(LOG_DEBUG, "connection to client closed");
+ LOG(DEBUG, "connection to client closed");
- LOG(LOG_DEBUG, "connection finished");
+ LOG(DEBUG, "connection finished");
}
use_invalid_cert = (!strcmp(hostname, "invalid"));
if (proxy_certificate_path(hostname, path, sizeof(path)) != 0) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): \
failed to get proxy certificate path");
return -1;
result = gnutls_certificate_allocate_credentials(x509_cred);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): \
gnutls_certificate_allocate_credentials(): %s",
gnutls_strerror(result));
PROXY_CA_FILE,
GNUTLS_X509_FMT_PEM);
if (result <= 0) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): can't read CA file: '%s'",
PROXY_CA_FILE);
gnutls_certificate_free_credentials(*x509_cred);
GNUTLS_X509_FMT_PEM);
}
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): \
can't read server certificate ('%s') or key file ('%s'): %s",
path, PROXY_KEY_FILE, gnutls_strerror(result));
result = gnutls_init(session, GNUTLS_SERVER);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): gnutls_init(): %s",
gnutls_strerror(result));
gnutls_certificate_free_credentials(*x509_cred);
}
result = gnutls_priority_set(*session, global_tls_priority_cache);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): gnutls_priority_set(): %s",
gnutls_strerror(result));
gnutls_deinit(*session);
result = gnutls_credentials_set(*session,
GNUTLS_CRD_CERTIFICATE, *x509_cred);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_client(): gnutls_credentials_set(): %s",
gnutls_strerror(result));
gnutls_deinit(*session);
result = gnutls_certificate_allocate_credentials(x509_cred);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_server(): \
gnutls_certificate_allocate_credentials(): %s",
gnutls_strerror(result));
result = gnutls_init(session, GNUTLS_CLIENT);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_server(): gnutls_init(): %s",
gnutls_strerror(result));
gnutls_certificate_free_credentials(*x509_cred);
}
result = gnutls_priority_set(*session, global_tls_priority_cache);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_server(): gnutls_priority_set(): %s",
gnutls_strerror(result));
gnutls_deinit(*session);
result = gnutls_credentials_set(*session,
GNUTLS_CRD_CERTIFICATE, *x509_cred);
if (result != GNUTLS_E_SUCCESS) {
- LOG(LOG_ERROR,
+ LOG(ERROR,
"initialize_tls_session_server(): gnutls_credentials_set(): %s",
gnutls_strerror(result));
gnutls_deinit(*session);
}
+static int fdopen_read_write(int socket, FILE **read_fd, FILE **write_fd) {
+ *read_fd = fdopen(socket, "r");
+ if (*read_fd == NULL) {
+ LOG_PERROR(WARNING, "fdopen_read_write(): fdopen(\"r\") failed");
+ return -1;
+ }
+
+ *write_fd = fdopen(dup(socket), "w");
+ if (*write_fd == NULL) {
+ LOG_PERROR(WARNING, "fdopen_read_write(): fdopen(\"w\") failed");
+ fclose(*read_fd);
+ *read_fd = NULL; /* "tell" caller read_fd is already closed */
+ return -1;
+ }
+
+ return 0;
+}
+
/* Read HTTP request line and headers (ignored).
*
* On success 0 is returned, -1 on client error, -2 on unexpected EOF.
if (fgets(request, (int)length, client_fd) == NULL) {
if (ferror(client_fd)) {
- LOG_PERROR(LOG_WARNING, "read_http_request(): fgets()");
+ LOG_PERROR(WARNING, "read_http_request(): fgets()");
return -1;
}
-
+ /* EOF */
return -2;
}
}
}
if (ferror(client_fd)) {
- LOG_PERROR(LOG_WARNING, "read_http_request(): fgets()");
+ LOG_PERROR(WARNING, "read_http_request(): fgets()");
return -1;
}
}
static void send_bad_request(FILE *client_fd) {
-#define RESPONSE_ERROR "400 Bad Request"
-#define RESPONSE_MSG "Your browser sent an invalid request."
- fprintf(client_fd, HTTP_RESPONSE_FORMAT,
- RESPONSE_ERROR, RESPONSE_ERROR, RESPONSE_ERROR,
- RESPONSE_MSG);
-#undef RESPONSE_ERROR
-#undef RESPONSE_MSG
+ const char error[] = "400 Bad Request";
+ const char msg[] = "Your browser sent an invalid request.";
+ fprintf(client_fd, HTTP_RESPONSE_FORMAT, error, "", error, error, msg);
+ fflush(client_fd);
}
static void send_forwarding_failure(FILE *client_fd) {
-#define RESPONSE_ERROR "503 Forwarding failure"
-#define RESPONSE_MSG "Failed to connect to server, check logs."
- fprintf(client_fd, HTTP_RESPONSE_FORMAT,
- RESPONSE_ERROR, RESPONSE_ERROR, RESPONSE_ERROR,
- RESPONSE_MSG);
-#undef RESPONSE_ERROR
-#undef RESPONSE_MSG
+ const char error[] = "503 Forwarding failure";
+ const char msg[] = "Failed to connect to server, check logs.";
+ fprintf(client_fd, HTTP_RESPONSE_FORMAT, error, "", error, error, msg);
+ fflush(client_fd);
}
static void tls_send_invalid_cert_message(gnutls_session_t session) {
-#define RESPONSE_ERROR "500 Internal Server Error"
-#define RESPONSE_MSG "Server certificate validation failed, check logs."
+ const char error[] = "500 Internal Server Error";
+ const char msg[] = "Server certificate validation failed, check logs.";
int result;
- char buffer[sizeof(HTTP_RESPONSE_FORMAT) - 1 /* '\0' */
- - 4 * 2 /* four %s */
- + (sizeof(RESPONSE_ERROR) - 1 /* '\0' */) * 3
- + sizeof(RESPONSE_MSG) - 1 /* '\0' */
- + 1 /* '\0' */];
-
- result = snprintf(buffer, sizeof(buffer),
- HTTP_RESPONSE_FORMAT,
- RESPONSE_ERROR, RESPONSE_ERROR, RESPONSE_ERROR,
- RESPONSE_MSG);
- if (result < 0) {
- LOG_PERROR(LOG_ERROR,
- "tls_send_invalid_cert_message(): snprintf failed");
- return;
- } else if ((size_t)result >= sizeof(buffer)) {
- LOG(LOG_ERROR,
- "tls_send_invalid_cert_message(): snprintf buffer too short");
- return;
- }
-
- gnutls_record_send(session, buffer, sizeof(buffer) - 1);
- /* don't send trailing '\0' */
-#undef RESPONSE_ERROR
-#undef RESPONSE_MSG
+ char buffer[sizeof(HTTP_RESPONSE_FORMAT)
+ + 3 * sizeof(error) + sizeof(msg)];
+
+ result = snprintf(buffer, sizeof(buffer), HTTP_RESPONSE_FORMAT,
+ error, "", error, error, msg);
+ assert(result > 0 && (size_t)result < sizeof(buffer));
+
+ gnutls_record_send(session, buffer, strlen(buffer));
}
fds[1].revents = 0;
for (;;) {
- int result = poll(fds, 2, -1 /* no timeout */);
+ int result = poll(fds, 2 /* fd count */, -1 /* no timeout */);
if (result < 0) {
- LOG_PERROR(LOG_ERROR, "transfer_data(): poll()");
+ LOG_PERROR(ERROR, "transfer_data(): poll()");
return;
}
ssize_t size_written;
char buffer[4096];
- LOG(LOG_DEBUG, "read_from_write_to(): %d -> %d", from, to);
+ LOG(DEBUG, "read_from_write_to(): %d -> %d", from, to);
size_read = read(from, buffer, sizeof(buffer));
if (size_read < 0) {
- LOG_PERROR(LOG_WARNING, "read_from_write_to(): read()");
+ LOG_PERROR(WARNING, "read_from_write_to(): read()");
return -1;
- }
/* EOF */
- if (size_read == 0) {
+ } else if (size_read == 0) {
return -1;
}
size_written = write(to, buffer, (size_t)size_read);
if (size_written < 0) {
- LOG_PERROR(LOG_WARNING, "read_from_write_to(): write()");
+ LOG_PERROR(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!",
+ LOG(ERROR, "read_from_write_to(): only written %ld of %ld bytes!",
(long int)size_written, (long int)size_read);
return -1;
}
if (gnutls_record_get_max_size(server_session) < buffer_size) {
buffer_size = gnutls_record_get_max_size(server_session);
}
- LOG(LOG_DEBUG, "transfer_data_tls(): suggested buffer size: %ld",
+ LOG(DEBUG, "transfer_data_tls(): suggested buffer size: %ld",
(long int)buffer_size);
for (;;) {
- int result = poll(fds, 2, -1 /* no timeout */);
+ int result = poll(fds, 2 /* fd count */, -1 /* no timeout */);
if (result < 0) {
- LOG_PERROR(LOG_ERROR, "transfer_data(): poll()");
+ LOG_PERROR(ERROR, "transfer_data(): poll()");
return;
}
if (buffer_size > sizeof(buffer)) {
buffer_size = sizeof(buffer);
}
- LOG(LOG_DEBUG, "read_from_write_to_tls(): used buffer size: %ld",
+ LOG(DEBUG, "read_from_write_to_tls(): used buffer size: %ld",
(long int)buffer_size);
size_read = gnutls_record_recv(from, buffer, buffer_size);
if (size_read < 0) {
- LOG(LOG_WARNING, "read_from_write_to_tls(): gnutls_record_recv(): %s",
+ LOG(WARNING, "read_from_write_to_tls(): gnutls_record_recv(): %s",
gnutls_strerror((int)size_read));
return -1;
- }
/* EOF */
- if (size_read == 0) {
+ } else if (size_read == 0) {
return -1;
}
size_written = gnutls_record_send(to, buffer, (size_t)size_read);
if (size_written < 0) {
- LOG(LOG_WARNING, "read_from_write_to_tls(): gnutls_record_send(): %s",
+ LOG(WARNING, "read_from_write_to_tls(): gnutls_record_send(): %s",
gnutls_strerror((int)size_written));
return -1;
}
if (size_read != size_written) {
- LOG(LOG_ERROR, "read_from_write_to_tls(): only written %ld of %ld bytes!",
+ 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 (gai_return != 0) {
- LOG_PERROR(LOG_WARNING, "connect_to_host(): getaddrinfo()");
+ if (gai_return == EAI_SYSTEM) {
+ LOG_PERROR(WARNING, "connect_to_host(): getaddrinfo()");
+ } else {
+ LOG(WARNING, "connect_to_host(): getaddrinfo(): %s",
+ gai_strerror(gai_return));
+ }
return -1;
}
server->ai_socktype,
server->ai_protocol);
if (server_socket == -1) {
- LOG_PERROR(LOG_DEBUG, "connect_to_host(): socket(), trying next");
+ LOG_PERROR(DEBUG, "connect_to_host(): socket(), trying next");
continue;
}
if (connect(server_socket, server->ai_addr, server->ai_addrlen) != -1) {
break;
}
- LOG_PERROR(LOG_DEBUG, "connect_to_host(): connect(), trying next");
+ LOG_PERROR(DEBUG, "connect_to_host(): connect(), trying next");
close(server_socket);
}
freeaddrinfo(gai_result);
if (server == NULL) {
- LOG_PERROR(LOG_WARNING, "connect_to_host(): no server found, abort");
+ LOG_PERROR(WARNING, "connect_to_host(): no server found, abort");
return -1;
}