X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Fconnection.c;h=bfdac1c6db59df105ae2ac9fdc659be004da9e3a;hb=f1a626728ee8be94ebb023c6cfb2f68684671450;hp=2732f30caa9b700e3d6664262312c14a46afd8d5;hpb=8bc073500cb894b9fd974b53801f7daa86e96d12;p=tlsproxy%2Ftlsproxy.git diff --git a/src/connection.c b/src/connection.c index 2732f30..bfdac1c 100644 --- a/src/connection.c +++ b/src/connection.c @@ -31,11 +31,28 @@ #include -/* Maximum line of a HTTP request line. Longer request lines are aborted with - * an error. The standard doesn't specify a maximum line length but this - * should be a good limit to make processing simpler. */ +/* Maximum length of a HTTP request line. Longer request lines are aborted + * with an error. The standard doesn't specify a maximum line length but this + * should be a good limit to make processing simpler. As HTTPS is used this + * doesn't limit long GET requests. */ #define MAX_REQUEST_LINE 4096 +/* 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. */ +#define HTTP_RESPONSE_FORMAT "HTTP/1.0 %s\r\n\ +Content-Type: text/html; charset=US-ASCII\r\n\ +\r\n\ +\n\ +\n\ +%s\n\ +\n\ +

%s

\n\ +

\n\ +\n\ +\n" + static int initialize_tls_session_client(int peer_socket, const char *hostname, @@ -50,10 +67,8 @@ static void send_bad_request(FILE *client_fd); static void send_forwarding_failure(FILE *client_fd); static void tls_send_invalid_cert_message(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); @@ -73,7 +88,7 @@ void handle_connection(int client_socket) { char host[MAX_REQUEST_LINE]; char port[5 + 1]; - int version_minor; + int version_minor; /* HTTP/1.x */ int result; /* client_x509_cred is used when talking to the client (acting as a TSL @@ -179,9 +194,38 @@ void handle_connection(int client_socket) { LOG(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 + * verify the server certificate. */ + if (global_passthrough_unknown) { + char path[1024]; + FILE *file = NULL; + + if (-2 == server_certificate_path(&file, host, path, sizeof(path))) { + /* 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); + + LOG(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"); + + goto out; + } + /* server_certificate_path() may have opened the file, close it. */ + if (NULL != file) { + fclose(file); + } + } + + /* Initialize TLS client credentials to talk to the server. */ 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); @@ -207,13 +251,14 @@ void handle_connection(int client_socket) { if (0 != verify_tls_connection(server_session, host)) { LOG(LOG_ERROR, "server certificate validation failed!"); /* We send the error message over our TLS connection to the client, - * but with an invalid certificate. */ + * but with an invalid certificate. No data is transfered from/to the + * target server. */ validation_failed = 1; } /* Initialize TLS server credentials to talk to the client. */ result = initialize_tls_session_client(client_socket, - /* use special host if the server + /* use a special host if the server * certificate was invalid */ (validation_failed) ? "invalid" : host, @@ -253,14 +298,14 @@ void handle_connection(int client_socket) { goto out; } - LOG(LOG_DEBUG, "transferring data"); + LOG(LOG_DEBUG, "transferring TLS data"); - /* Proxy data between client and server until one suite is done (EOF or + /* 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 data"); + LOG(LOG_DEBUG, "finished transferring TLS data"); out: /* Close TLS sessions if necessary. Use GNUTLS_SHUT_RDWR so the data is @@ -327,7 +372,16 @@ static int initialize_tls_session_client(int peer_socket, hostname); return -1; } - snprintf(path, sizeof(path), PROXY_SERVER_CERT_FORMAT, hostname); + result = snprintf(path, sizeof(path), PROXY_SERVER_CERT_FORMAT, hostname); + if (result < 0) { + LOG_PERROR(LOG_ERROR, + "initialize_tls_session_client(): snprintf failed"); + return -1; + } else if ((size_t)result >= sizeof(path)) { + LOG(LOG_ERROR, + "initialize_tls_session_client(): snprintf buffer too short"); + return -1; + } result = gnutls_certificate_allocate_credentials(x509_cred); if (GNUTLS_E_SUCCESS != result) { @@ -343,17 +397,17 @@ gnutls_certificate_allocate_credentials(): %s", 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); + gnutls_certificate_free_credentials(*x509_cred); + return -1; + } + } /* If the invalid hostname was specified do nothing, we use a self-signed * certificate in this case. */ - } else { - result = 1; - } - 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. */ if (!use_invalid_cert) { result = gnutls_certificate_set_x509_key_file(*x509_cred, @@ -372,24 +426,28 @@ gnutls_certificate_allocate_credentials(): %s", "initialize_tls_session_client(): \ can't read server certificate ('%s') or key file ('%s'): %s", path, PROXY_KEY_FILE, gnutls_strerror(result)); + gnutls_certificate_free_credentials(*x509_cred); /* Could be a missing certificate. */ return -2; } - gnutls_certificate_set_dh_params(*x509_cred, tls_dh_params); + gnutls_certificate_set_dh_params(*x509_cred, global_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)); + gnutls_certificate_free_credentials(*x509_cred); return -1; } - result = gnutls_priority_set(*session, tls_priority_cache); + result = gnutls_priority_set(*session, global_tls_priority_cache); if (GNUTLS_E_SUCCESS != result) { LOG(LOG_ERROR, "initialize_tls_session_client(): gnutls_priority_set(): %s", gnutls_strerror(result)); + gnutls_deinit(*session); + gnutls_certificate_free_credentials(*x509_cred); return -1; } result = gnutls_credentials_set(*session, @@ -398,6 +456,8 @@ can't read server certificate ('%s') or key file ('%s'): %s", LOG(LOG_ERROR, "initialize_tls_session_client(): gnutls_credentials_set(): %s", gnutls_strerror(result)); + gnutls_deinit(*session); + gnutls_certificate_free_credentials(*x509_cred); return -1; } @@ -424,13 +484,16 @@ gnutls_certificate_allocate_credentials(): %s", LOG(LOG_ERROR, "initialize_tls_session_server(): gnutls_init(): %s", gnutls_strerror(result)); + gnutls_certificate_free_credentials(*x509_cred); return -1; } - gnutls_priority_set(*session, tls_priority_cache); + gnutls_priority_set(*session, global_tls_priority_cache); if (GNUTLS_E_SUCCESS != result) { LOG(LOG_ERROR, "initialize_tls_session_server(): gnutls_priority_set(): %s", gnutls_strerror(result)); + gnutls_deinit(*session); + gnutls_certificate_free_credentials(*x509_cred); return -1; } result = gnutls_credentials_set(*session, @@ -439,6 +502,8 @@ gnutls_certificate_allocate_credentials(): %s", LOG(LOG_ERROR, "initialize_tls_session_server(): gnutls_credentials_set(): %s", gnutls_strerror(result)); + gnutls_deinit(*session); + gnutls_certificate_free_credentials(*x509_cred); return -1; } @@ -479,20 +544,55 @@ static int read_http_request(FILE *client_fd, char *request, size_t length) { } static void send_bad_request(FILE *client_fd) { - fprintf(client_fd, "HTTP/1.0 400 Bad Request\r\n"); - fprintf(client_fd, "\r\n"); +#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 } static void send_forwarding_failure(FILE *client_fd) { - fprintf(client_fd, "HTTP/1.0 503 Forwarding failure\r\n"); - fprintf(client_fd, "\r\n"); +#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 } static void tls_send_invalid_cert_message(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); +#define RESPONSE_ERROR "500 Internal Server Error" +#define RESPONSE_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 } -#if 0 /* Transfer data between client and server sockets until one closes the * connection. */ static void transfer_data(int client, int server) { @@ -544,6 +644,8 @@ static int read_from_write_to(int from, int to) { ssize_t size_written; char buffer[4096]; + LOG(LOG_DEBUG, "read_from_write_to(): %d -> %d", from, to); + size_read = read(from, buffer, sizeof(buffer)); if (0 > size_read) { LOG_PERROR(LOG_WARNING, "read_from_write_to(): read()"); @@ -567,7 +669,6 @@ static int read_from_write_to(int from, int to) { return 0; } -#endif /* Transfer data between client and server TLS connection until one closes the * connection. */