X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Fconnection.c;h=fb854da4536937ae43f136ff6f418cbbaf776698;hb=HEAD;hp=a860a494c2b18e7d1bbe04b9f8902d7d77b83272;hpb=075cfe8260e8924bc62f08980e7034e439dddbcf;p=tlsproxy%2Ftlsproxy.git diff --git a/src/connection.c b/src/connection.c index a860a49..fb854da 100644 --- a/src/connection.c +++ b/src/connection.c @@ -1,7 +1,7 @@ /* * Handle connections. * - * Copyright (C) 2011-2013 Simon Ruderich + * Copyright (C) 2011-2014 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 @@ -26,8 +26,11 @@ #include #include #include +#include #include +#include + /* 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 @@ -38,7 +41,8 @@ /* 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$s!), the last is the message. */ + * two are the error code (no %n$s which is not in C98!), 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\ @@ -59,7 +63,7 @@ static int initialize_tls_session_client(int peer_socket, static int initialize_tls_session_server(int peer_socket, gnutls_session_t *session, gnutls_certificate_credentials_t *x509_cred); -static int initialize_tls_session_both(int flags, +static int initialize_tls_session_both(unsigned int flags, int peer_socket, gnutls_session_t *session, gnutls_certificate_credentials_t *x509_cred); @@ -84,6 +88,8 @@ static int connect_to_host(const char *hostname, const char *port); static int parse_request(const char *buffer, char *host, char *port, int *version_minor); +static void log_session_information(gnutls_session_t session); + void handle_connection(int client_socket) { int server_socket; @@ -96,9 +102,9 @@ void handle_connection(int client_socket) { int version_minor; /* x in HTTP/1.x */ int result; - /* client_x509_cred is used when talking to the client (acting as a TSL + /* client_x509_cred is used when talking to the client (acting as a TLS * server), server_x509_cred is used when talking to the server (acting as - * a TSL client). */ + * a TLS client). */ gnutls_certificate_credentials_t client_x509_cred, server_x509_cred; gnutls_session_t client_session, server_session; @@ -138,7 +144,7 @@ void handle_connection(int client_socket) { send_bad_request(client_fd_write); goto out; } else if (result == -3) { - LOG(DEBUG1, "read_http_request(): proxy authentication failed"); + LOG(WARNING, "read_http_request(): proxy authentication failed"); send_authentication_required(client_fd_write); goto out; } @@ -149,7 +155,7 @@ void handle_connection(int client_socket) { goto out; } - LOG(DEBUG1, "target: %s:%s (HTTP 1.%d)", host, port, version_minor); + LOG(DEBUG2, "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) { @@ -192,7 +198,7 @@ void handle_connection(int client_socket) { /* Check response of proxy server. */ if (strncmp(buffer, "HTTP/1.0 200", 12)) { - LOG(WARNING, "bad proxy response: %s", buffer); + LOG(WARNING, "bad proxy response: >%s<", buffer); send_forwarding_failure(client_fd_write); goto out; } @@ -201,7 +207,7 @@ void handle_connection(int client_socket) { LOG(DEBUG1, "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 + * 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]; @@ -253,6 +259,10 @@ void handle_connection(int client_socket) { LOG(DEBUG1, "server TLS handshake finished"); + if (global_log_level >= LOG_DEBUG2_LEVEL) { + log_session_information(server_session); + } + /* Make sure the server certificate is valid and known. */ if (verify_tls_connection(server_session, host) != 0) { LOG(ERROR, "server certificate validation failed!"); @@ -296,6 +306,10 @@ void handle_connection(int client_socket) { LOG(DEBUG1, "client TLS handshake finished"); + if (global_log_level >= LOG_DEBUG2_LEVEL) { + log_session_information(client_session); + } + /* 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. */ @@ -337,8 +351,6 @@ out: } if (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); } @@ -406,6 +418,11 @@ static int initialize_tls_session_client(int peer_socket, PROXY_CA_PATH); gnutls_certificate_free_credentials(*x509_cred); return -1; + } else if (result != 1) { + /* Must contain only one CA, our proxy CA. */ + LOG(ERROR, "initialize_tls_session_client(): multiple CAs found"); + gnutls_certificate_free_credentials(*x509_cred); + return -1; } } /* If the invalid hostname was specified do nothing, we use a self-signed @@ -457,7 +474,7 @@ static int initialize_tls_session_server(int peer_socket, return initialize_tls_session_both(GNUTLS_CLIENT, peer_socket, session, x509_cred); } -static int initialize_tls_session_both(int flags, +static int initialize_tls_session_both(unsigned int flags, int peer_socket, gnutls_session_t *session, gnutls_certificate_credentials_t *x509_cred) { @@ -566,6 +583,8 @@ static int read_http_request(FILE *client_fd, char *request, size_t length) { if (ferror(client_fd)) { LOG_PERROR(WARNING, "read_http_request(): fgets()"); return -1; + } else if (feof(client_fd)) { + return -2; } if (global_http_digest_authorization != NULL && !found_proxy_authorization) { @@ -599,6 +618,7 @@ static void tls_send_invalid_cert_message(gnutls_session_t session) { const char msg[] = "Server certificate validation failed, check logs."; int result; + ssize_t size_written; char buffer[sizeof(HTTP_RESPONSE_FORMAT) + 3 * sizeof(error) + sizeof(msg)]; @@ -606,7 +626,13 @@ static void tls_send_invalid_cert_message(gnutls_session_t session) { error, "", error, error, msg); assert(result > 0 && (size_t)result < sizeof(buffer)); - gnutls_record_send(session, buffer, strlen(buffer)); + size_written = gnutls_record_send(session, buffer, strlen(buffer)); + if (size_written < 0) { + LOG(WARNING, "tls_send_invalid_cert_message(): " + "gnutls_record_send(): %s", + gnutls_strerror((int)size_written)); + } + /* Just an error message, no need to check if everything was written. */ } @@ -621,7 +647,7 @@ static void transfer_data(int client, int server) { fds[1].events = POLLIN | POLLPRI | POLLHUP | POLLERR; fds[1].revents = 0; - LOG(DEBUG1, "transfer_data(): %d -> %d", client, server); + LOG(DEBUG2, "transfer_data(): %d -> %d", client, server); for (;;) { int result = poll(fds, 2 /* fd count */, -1 /* no timeout */); @@ -678,8 +704,8 @@ static int read_from_write_to(int from, int to) { return -1; } if (size_read != size_written) { - 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 %zu of %zu bytes!", + size_written, size_read); return -1; } @@ -706,8 +732,8 @@ static void transfer_data_tls(int client, int server, if (gnutls_record_get_max_size(server_session) < buffer_size) { buffer_size = gnutls_record_get_max_size(server_session); } - LOG(DEBUG1, "transfer_data_tls(): suggested buffer size: %ld", - (long int)buffer_size); + LOG(DEBUG2, "transfer_data_tls(): suggested buffer size: %zu", + buffer_size); for (;;) { int result = poll(fds, 2 /* fd count */, -1 /* no timeout */); @@ -750,16 +776,32 @@ static int read_from_write_to_tls(gnutls_session_t from, size_t buffer_size) { ssize_t size_read; ssize_t size_written; - char buffer[16384]; + char buffer[16384]; /* GnuTLS default maximum */ if (buffer_size > sizeof(buffer)) { - LOG(WARNING, "read_from_write_to_tls(): reduced buffer size to %ld", - (long int)(sizeof(buffer))); + LOG(WARNING, "read_from_write_to_tls(): reduced buffer size to %zu", + sizeof(buffer)); buffer_size = sizeof(buffer); } size_read = gnutls_record_recv(from, buffer, buffer_size); if (size_read < 0) { + /* Allow rehandshakes. As handshakes might be insecure make sure that + * %SAFE_RENEGOTIATION is used in GnuTLS's priority string. */ + if (size_read == GNUTLS_E_REHANDSHAKE) { + int result; + + LOG(DEBUG1, "server requested TLS rehandshake"); + + result = gnutls_handshake(from); + if (result != GNUTLS_E_SUCCESS) { + LOG(WARNING, "server TLS rehandshake failed: %s", + gnutls_strerror(result)); + return -1; + } + return 0; + } + LOG(WARNING, "read_from_write_to_tls(): gnutls_record_recv(): %s", gnutls_strerror((int)size_read)); return -1; @@ -775,8 +817,8 @@ static int read_from_write_to_tls(gnutls_session_t from, return -1; } if (size_read != size_written) { - 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 %zu of %zu bytes!", + size_written, size_read); return -1; } @@ -802,8 +844,10 @@ static int connect_to_host(const char *hostname, const char *port) { gai_hints.ai_socktype = SOCK_STREAM; gai_hints.ai_protocol = 0; gai_hints.ai_flags = AI_NUMERICSERV /* given port is numeric */ +#ifdef AI_ADDRCONFIG | AI_ADDRCONFIG /* supported by this computer */ - | AI_V4MAPPED; /* support IPv4 through IPv6 */ +#endif + ; gai_return = getaddrinfo(hostname, port, &gai_hints, &gai_result); if (gai_return != 0) { if (gai_return == EAI_SYSTEM) { @@ -881,3 +925,72 @@ static int parse_request(const char *request, char *host, char *port, return 0; } + + +static void log_session_information(gnutls_session_t session) { + /* From doc/examples/ex-session-info.c of GnuTLS 3.2.3's tarball and + * modified, thanks. */ + + const char *tmp; + gnutls_credentials_type_t cred; + gnutls_kx_algorithm_t kx; + int dhe, ecdh; + + dhe = 0; + ecdh = 0; + + /* Key exchange algorithm. */ + kx = gnutls_kx_get(session); + LOG(DEBUG2, "- key exchange: %s", gnutls_kx_get_name(kx)); + + /* Authentication type. */ + cred = gnutls_auth_get_type(session); + switch (cred) { + case GNUTLS_CRD_CERTIFICATE: + if (kx == GNUTLS_KX_DHE_RSA + || kx == GNUTLS_KX_DHE_DSS) { + dhe = 1; +#ifdef GNUTLS_KX_ECDHE_RSA + } else if (kx == GNUTLS_KX_ECDHE_RSA + || kx == GNUTLS_KX_ECDHE_ECDSA) { + ecdh = 1; +#endif + } + break; + + case GNUTLS_CRD_IA: + case GNUTLS_CRD_SRP: + case GNUTLS_CRD_PSK: + case GNUTLS_CRD_ANON: + default: + /* This shouldn't occur. */ + LOG(WARNING, "unexpected authentication method: %d", cred); + break; + } + + /* Information about key exchange. */ + if (dhe) { + LOG(DEBUG2, "- ephemeral DH using prime of %d bits", + gnutls_dh_get_prime_bits(session)); + } else if (ecdh) { +#ifdef GNUTLS_KX_ECDHE_RSA + LOG(DEBUG2, "- ephemeral ECDH using curve %s", + gnutls_ecc_curve_get_name(gnutls_ecc_curve_get(session))); +#endif + } + + tmp = gnutls_protocol_get_name(gnutls_protocol_get_version(session)); + LOG(DEBUG2, "- protocol: %s", tmp); /* e.g. TLS 1.0 */ + + tmp = gnutls_certificate_type_get_name(gnutls_certificate_type_get(session)); + LOG(DEBUG2, "- certificate type: %s", tmp); + + tmp = gnutls_compression_get_name(gnutls_compression_get(session)); + LOG(DEBUG2, "- compression: %s", tmp); + + tmp = gnutls_cipher_get_name(gnutls_cipher_get(session)); + LOG(DEBUG2, "- cipher: %s", tmp); + + tmp = gnutls_mac_get_name(gnutls_mac_get(session)); + LOG(DEBUG2, "- MAC: %s", tmp); +}