X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Fconnection.c;h=5a08de7431f07733179982b48e3cf7bac8e4d737;hb=b7ce41b809a3b3533d398c0da8fd9787c149434c;hp=1421afa0c384073e51776b5bda129f031d1fcf29;hpb=946885b04de70f8481f58160de12f3ee3b0b380a;p=tlsproxy%2Ftlsproxy.git diff --git a/src/connection.c b/src/connection.c index 1421afa..5a08de7 100644 --- a/src/connection.c +++ b/src/connection.c @@ -1,7 +1,7 @@ /* * Handle connections. * - * Copyright (C) 2011 Simon Ruderich + * Copyright (C) 2011-2013 Simon Ruderich * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -21,21 +21,36 @@ #include "connection.h" #include "verify.h" -/* close() */ -#include -/* getaddrinfo() */ +#include +#include +#include #include -/* poll() */ #include -/* errno */ -#include +#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 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\ +%s\r\n\ +\n\ +\n\ +%s\n\ +\n\ +

%s

\n\ +

\n\ +\n\ +\n" + static int initialize_tls_session_client(int peer_socket, const char *hostname, @@ -45,19 +60,20 @@ static int initialize_tls_session_server(int peer_socket, 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_authentication_required(FILE *client_fd); static void send_forwarding_failure(FILE *client_fd); -static void tls_send_server_error(gnutls_session_t session); +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); -static int read_from_write_to_tls(gnutls_session_t from, gnutls_session_t to); +static int read_from_write_to_tls(gnutls_session_t from, gnutls_session_t to, + size_t buffer_size); static int connect_to_host(const char *hostname, const char *port); @@ -67,13 +83,13 @@ static int parse_request(const char *buffer, char *host, char *port, 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; + int version_minor; /* x in HTTP/1.x */ int result; /* client_x509_cred is used when talking to the client (acting as a TSL @@ -86,177 +102,227 @@ void handle_connection(int client_socket) { int client_session_init, server_session_init; /* gnutls_handshake() called? - used for goto out */ int client_session_started, server_session_started; + /* Validation failed? If yes we need to send the special "invalid" + * 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 (NULL == client_fd) { - 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)); - if (-1 == result) { - /* Read error. */ - LOG(LOG_WARNING, "read_http_request(): client read error"); + result = read_http_request(client_fd_read, buffer, sizeof(buffer)); + if (result == -1) { + LOG(WARNING, "read_http_request(): client read error"); goto out; - } else if (-2 == result) { - /* EOF */ - LOG(LOG_WARNING, "read_http_request(): client EOF"); - send_bad_request(client_fd); + } else if (result == -2) { + LOG(WARNING, "read_http_request(): client EOF"); + send_bad_request(client_fd_write); + goto out; + } else if (result == -3) { + LOG(DEBUG, "read_http_request(): proxy authentication failed"); + send_authentication_required(client_fd_write); goto out; } - if (0 != parse_request(buffer, host, port, &version_minor)) { - LOG(LOG_WARNING, "bad request: %s", buffer); - send_bad_request(client_fd); + if (parse_request(buffer, host, port, &version_minor) != 0) { + 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 (NULL != global_proxy_host && NULL != global_proxy_port) { - LOG(LOG_DEBUG, "connecting to %s:%s", global_proxy_host, - global_proxy_port); + if (global_proxy_host != NULL && global_proxy_port != NULL) { + 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 (-1 == server_socket) { - LOG(LOG_WARNING, "failed to connect to server"); - send_forwarding_failure(client_fd); + if (server_socket < 0) { + LOG(WARNING, "failed to connect to server"); + send_forwarding_failure(client_fd_write); goto out; } - server_fd = fdopen(server_socket, "a+"); - if (NULL == server_fd) { - 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 (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"); + if (global_proxy_host != NULL && global_proxy_port != NULL) { + 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)); - if (-1 == result) { - /* Read error. */ - LOG(LOG_WARNING, "read_http_request(): proxy read error"); - send_forwarding_failure(client_fd); + result = read_http_request(server_fd_read, buffer, sizeof(buffer)); + if (result == -1) { + LOG(WARNING, "read_http_request(): proxy read error"); + send_forwarding_failure(client_fd_write); goto out; - } else if (-2 == result) { - /* EOF */ - LOG(LOG_WARNING, "read_http_request(): proxy EOF"); - send_forwarding_failure(client_fd); + } else if (result == -2) { + LOG(WARNING, "read_http_request(): proxy EOF"); + send_forwarding_failure(client_fd_write); goto out; } /* Check response of proxy server. */ - if (0 != strncmp(buffer, "HTTP/1.0 200", 12)) { - LOG(LOG_WARNING, "bad proxy response: %s", buffer); - send_forwarding_failure(client_fd); + if (strncmp(buffer, "HTTP/1.0 200", 12)) { + 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"); - /* 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); + /* 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[TLSPROXY_MAX_PATH_LENGTH]; + FILE *file = NULL; - /* 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; + if (server_certificate_file(&file, host, path, sizeof(path)) == -2) { + /* We've established a connection, tell the client. */ + 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, "transferring data"); - /* 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; + /* Proxy data between client and server until one side is done + * (EOF or error). */ + transfer_data(client_socket, server_socket); - LOG(LOG_DEBUG, "client TLS handshake finished"); + LOG(DEBUG, "finished transferring data"); + + goto out; + } + /* server_certificate_file() may have opened the file, close it. */ + if (file != NULL) { + 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); + if (result != 0) { + 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 (GNUTLS_E_SUCCESS != result) { - LOG(LOG_WARNING, "server TLS handshake failed: %s", - gnutls_strerror(result)); - send_forwarding_failure(client_fd); + if (result != GNUTLS_E_SUCCESS) { + LOG(WARNING, "server TLS handshake failed: %s", + gnutls_strerror(result)); + send_forwarding_failure(client_fd_write); goto out; } server_session_started = 1; - LOG(LOG_DEBUG, "server TLS handshake finished, transferring data"); + LOG(DEBUG, "server TLS handshake finished"); /* 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); + if (verify_tls_connection(server_session, host) != 0) { + 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; + } + + /* Initialize TLS server credentials to talk to the client. */ + result = initialize_tls_session_client(client_socket, + /* use a special host if the server + * certificate was invalid */ + (validation_failed) ? "invalid" + : host, + &client_session, + &client_x509_cred); + if (result != 0) { + 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_write, "HTTP/1.0 200 Connection established\r\n"); + fprintf(client_fd_write, "\r\n"); + fflush(client_fd_write); + + 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(WARNING, "client TLS handshake failed: %s", + gnutls_strerror(result)); + send_forwarding_failure(client_fd_write); goto out; } + client_session_started = 1; + + 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 + * invalid certificate but better be sure. */ + if (validation_failed) { + tls_send_invalid_cert_message(client_session); + goto out; + } + + 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(DEBUG, "finished transferring TLS data"); out: /* Close TLS sessions if necessary. Use GNUTLS_SHUT_RDWR so the data is * reliable transmitted. */ - if (0 != server_session_started) { + if (server_session_started) { gnutls_bye(server_session, GNUTLS_SHUT_RDWR); } - if (0 != client_session_started) { + if (client_session_started) { gnutls_bye(client_session, GNUTLS_SHUT_RDWR); } - if (0 != server_session_init) { + if (server_session_init) { gnutls_deinit(server_session); gnutls_certificate_free_credentials(server_x509_cred); } - if (0 != client_session_init) { + if (client_session_init) { gnutls_deinit(client_session); gnutls_certificate_free_cas(client_x509_cred); gnutls_certificate_free_keys(client_x509_cred); @@ -264,21 +330,27 @@ out: } /* Close connection to server/proxy. */ - if (NULL != server_fd) { - fclose(server_fd); - } else if (-1 != server_socket) { + 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 (NULL != client_fd) { - 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"); } @@ -287,78 +359,95 @@ static int initialize_tls_session_client(int peer_socket, gnutls_session_t *session, gnutls_certificate_credentials_t *x509_cred) { int result; - char path[1024]; + int use_invalid_cert; + char path[TLSPROXY_MAX_PATH_LENGTH]; - /* 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); + /* The "invalid" hostname is special. If it's used we send an invalid + * certificate to let the client know something is wrong. */ + use_invalid_cert = (!strcmp(hostname, "invalid")); + + if (proxy_certificate_path(hostname, path, sizeof(path)) != 0) { + LOG(ERROR, + "initialize_tls_session_client(): " + "failed to get proxy certificate path"); 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", + if (result != GNUTLS_E_SUCCESS) { + 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; + if (!use_invalid_cert) { + result = gnutls_certificate_set_x509_trust_file(*x509_cred, + PROXY_CA_FILE, + GNUTLS_X509_FMT_PEM); + if (result <= 0) { + 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. */ + /* 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", + if (!use_invalid_cert) { + result = gnutls_certificate_set_x509_key_file(*x509_cred, + path, PROXY_KEY_FILE, + GNUTLS_X509_FMT_PEM); + /* If the invalid hostname was specified load our special "invalid" + * certificate. */ + } else { + result = gnutls_certificate_set_x509_key_file(*x509_cred, + PROXY_INVALID_CERT_FILE, + PROXY_KEY_FILE, + GNUTLS_X509_FMT_PEM); + } + if (result != GNUTLS_E_SUCCESS) { + LOG(ERROR, + "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, + if (result != GNUTLS_E_SUCCESS) { + 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); - if (GNUTLS_E_SUCCESS != result) { - LOG(LOG_ERROR, + result = gnutls_priority_set(*session, global_tls_priority_cache); + if (result != GNUTLS_E_SUCCESS) { + 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, GNUTLS_CRD_CERTIFICATE, *x509_cred); - if (GNUTLS_E_SUCCESS != result) { - LOG(LOG_ERROR, + if (result != GNUTLS_E_SUCCESS) { + LOG(ERROR, "initialize_tls_session_client(): gnutls_credentials_set(): %s", gnutls_strerror(result)); + gnutls_deinit(*session); + gnutls_certificate_free_credentials(*x509_cred); return -1; } @@ -372,34 +461,39 @@ static int initialize_tls_session_server(int peer_socket, 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", + if (result != GNUTLS_E_SUCCESS) { + 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, + if (result != GNUTLS_E_SUCCESS) { + 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); - if (GNUTLS_E_SUCCESS != result) { - LOG(LOG_ERROR, + result = gnutls_priority_set(*session, global_tls_priority_cache); + if (result != GNUTLS_E_SUCCESS) { + 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, GNUTLS_CRD_CERTIFICATE, *x509_cred); - if (GNUTLS_E_SUCCESS != result) { - LOG(LOG_ERROR, + if (result != GNUTLS_E_SUCCESS) { + LOG(ERROR, "initialize_tls_session_server(): gnutls_credentials_set(): %s", gnutls_strerror(result)); + gnutls_deinit(*session); + gnutls_certificate_free_credentials(*x509_cred); return -1; } @@ -409,51 +503,110 @@ gnutls_certificate_allocate_credentials(): %s", } +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. */ static int read_http_request(FILE *client_fd, char *request, size_t length) { char buffer[MAX_REQUEST_LINE]; + int found_proxy_authorization; - if (NULL == fgets(request, (int)length, client_fd)) { + assert(length <= INT_MAX); + 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; } - while (NULL != fgets(buffer, MAX_REQUEST_LINE, client_fd)) { + found_proxy_authorization = 0; + while (fgets(buffer, sizeof(buffer), client_fd) != NULL) { + const char *authentication = "Proxy-Authorization: Basic "; + + if (http_digest_authorization != NULL + && !strncmp(buffer, authentication, strlen(authentication))) { + found_proxy_authorization = 1; + + /* Check if the passphrase matches. */ + strtok(buffer, "\r\n"); + if (strcmp(buffer + strlen(authentication), + http_digest_authorization)) { + return -3; + } + } + /* End of header. */ - if (0 == strcmp(buffer, "\n") || 0 == strcmp(buffer, "\r\n")) { + if (!strcmp(buffer, "\n") || !strcmp(buffer, "\r\n")) { break; } } if (ferror(client_fd)) { - LOG_PERROR(LOG_WARNING, "read_http_request(): fgets()"); + LOG_PERROR(WARNING, "read_http_request(): fgets()"); return -1; } + if (http_digest_authorization != NULL && !found_proxy_authorization) { + return -3; + } + return 0; } static void send_bad_request(FILE *client_fd) { - fprintf(client_fd, "HTTP/1.0 400 Bad Request\r\n"); - fprintf(client_fd, "\r\n"); + 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_authentication_required(FILE *client_fd) { + const char error[] = "407 Proxy Authentication Required"; + const char auth[] = "Proxy-Authenticate: Basic realm=\"tlsproxy\"\r\n"; + const char msg[] = "TODO"; + fprintf(client_fd, HTTP_RESPONSE_FORMAT, error, auth, error, error, msg); + fflush(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"); + 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_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); +static void tls_send_invalid_cert_message(gnutls_session_t session) { + const char error[] = "500 Internal Server Error"; + const char msg[] = "Server certificate validation failed, check logs."; + + int result; + 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)); } -#if 0 /* Transfer data between client and server sockets until one closes the * connection. */ static void transfer_data(int client, int server) { @@ -466,22 +619,22 @@ static void transfer_data(int client, int server) { 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; } /* Data available from client. */ if (fds[0].revents & POLLIN || fds[0].revents & POLLPRI) { - if (0 != read_from_write_to(client, server)) { + if (read_from_write_to(client, server) != 0) { /* EOF (or other error) */ break; } } /* Data available from server. */ if (fds[1].revents & POLLIN || fds[1].revents & POLLPRI) { - if (0 != read_from_write_to(server, client)) { + if (read_from_write_to(server, client) != 0) { /* EOF (or other error) */ break; } @@ -505,36 +658,38 @@ static int read_from_write_to(int from, int to) { ssize_t size_written; char buffer[4096]; + 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()"); + if (size_read < 0) { + LOG_PERROR(WARNING, "read_from_write_to(): read()"); return -1; - } /* EOF */ - if (0 == size_read) { + } else if (size_read == 0) { return -1; } size_written = write(to, buffer, (size_t)size_read); - if (0 > size_written) { - LOG_PERROR(LOG_WARNING, "read_from_write_to(): write()"); + if (size_written < 0) { + 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!", - (long int)size_written, (long int)size_read); + 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) { + size_t buffer_size; + struct pollfd fds[2]; fds[0].fd = client; fds[0].events = POLLIN | POLLPRI | POLLHUP | POLLERR; @@ -543,23 +698,33 @@ static void transfer_data_tls(int client, int server, fds[1].events = POLLIN | POLLPRI | POLLHUP | POLLERR; fds[1].revents = 0; + /* Get maximum possible buffer size. */ + buffer_size = gnutls_record_get_max_size(client_session); + if (gnutls_record_get_max_size(server_session) < buffer_size) { + buffer_size = gnutls_record_get_max_size(server_session); + } + 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; } /* Data available from client. */ if (fds[0].revents & POLLIN || fds[0].revents & POLLPRI) { - if (0 != read_from_write_to_tls(client_session, server_session)) { + if (read_from_write_to_tls(client_session, server_session, + buffer_size) != 0) { /* 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)) { + if (read_from_write_to_tls(server_session, client_session, + buffer_size) != 0) { /* EOF (or other error) */ break; } @@ -578,45 +743,37 @@ static void transfer_data_tls(int client, int server, /* 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; + gnutls_session_t to, + size_t buffer_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; + if (buffer_size > sizeof(buffer)) { + buffer_size = sizeof(buffer); } + 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(WARNING, "read_from_write_to_tls(): gnutls_record_recv(): %s", + gnutls_strerror((int)size_read)); + return -1; /* EOF */ - if (0 == size_read) { + } else if (size_read == 0) { 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)); + if (size_written < 0) { + 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!", - (long int)size_written, (long int)size_read); + LOG(ERROR, "read_from_write_to_tls(): only written %ld of %ld bytes!", + (long int)size_written, (long int)size_read); return -1; } @@ -632,7 +789,7 @@ static int connect_to_host(const char *hostname, const char *port) { int server_socket; struct addrinfo *server; - if (NULL == hostname || NULL == port) { + if (hostname == NULL || port == NULL) { return -1; } @@ -645,35 +802,39 @@ static int connect_to_host(const char *hostname, const char *port) { | AI_ADDRCONFIG /* supported by this computer */ | AI_V4MAPPED; /* support IPv4 through IPv6 */ gai_return = getaddrinfo(hostname, port, &gai_hints, &gai_result); - if (0 != gai_return) { - LOG_PERROR(LOG_WARNING, "connect_to_host(): getaddrinfo()"); + if (gai_return != 0) { + 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; } /* Now try to connect to each server returned by getaddrinfo(), use the * first successful connect. */ - for (server = gai_result; NULL != server; server = server->ai_next) { + for (server = gai_result; server != NULL; server = server->ai_next) { server_socket = socket(server->ai_family, server->ai_socktype, server->ai_protocol); - if (-1 == server_socket) { - LOG_PERROR(LOG_DEBUG, "connect_to_host(): socket(), trying next"); + if (server_socket < 0) { + LOG_PERROR(DEBUG, "connect_to_host(): socket(), trying next"); continue; } - if (-1 != connect(server_socket, server->ai_addr, - server->ai_addrlen)) { + if (connect(server_socket, server->ai_addr, server->ai_addrlen) == 0) { break; } - LOG_PERROR(LOG_DEBUG, "connect_to_host(): connect(), trying next"); + LOG_PERROR(DEBUG, "connect_to_host(): connect(), trying next"); close(server_socket); } /* Make sure we free the result from getaddrinfo(). */ freeaddrinfo(gai_result); - if (NULL == server) { - LOG_PERROR(LOG_WARNING, "connect_to_host(): no server found, abort"); + if (server == NULL) { + LOG_PERROR(WARNING, "connect_to_host(): no server found, abort"); return -1; } @@ -694,20 +855,19 @@ static int parse_request(const char *request, char *host, char *port, char *position; /* scanf() doesn't check spaces. */ - if (0 != strncmp(request, "CONNECT ", 8)) { + if (strncmp(request, "CONNECT ", 8)) { return -1; } /* Check request and extract data, "host:port" is not yet separated. */ - if (2 != sscanf(request, "CONNECT %s HTTP/1.%d", - host, version_minor)) { + if (sscanf(request, "CONNECT %s HTTP/1.%d", host, version_minor) != 2) { return -1; } /* Make sure ":port" is there. */ - if (NULL == (position = strchr(host, ':'))) { + if ((position = strchr(host, ':')) == NULL) { return -1; } /* Make sure port is numeric. */ - if (1 != sscanf(position + 1, "%d", &port_unused)) { + if (sscanf(position + 1, "%d", &port_unused) != 1) { return -1; } /* Store it in *port. */