X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Fconnection.c;h=513be7e6d7a2d3012ae7fa1770feb16cdc0df591;hb=80e82203daef6daf7a16219876fc404e12f82c8a;hp=26947ffdbfd60968e3c0b229b188161a2767ba8f;hpb=d232e106feb871ff63736df76b708eb684d31b72;p=tlsproxy%2Ftlsproxy.git diff --git a/src/connection.c b/src/connection.c index 26947ff..513be7e 100644 --- a/src/connection.c +++ b/src/connection.c @@ -19,6 +19,7 @@ #include "tlsproxy.h" #include "connection.h" +#include "verify.h" /* close() */ #include @@ -47,11 +48,10 @@ static int initialize_tls_session_server(int peer_socket, 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); +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); @@ -84,6 +84,9 @@ 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"); @@ -94,6 +97,7 @@ void handle_connection(int client_socket) { 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) { @@ -173,35 +177,34 @@ void handle_connection(int client_socket) { 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); + /* 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; - /* 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 (-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, "starting client TLS handshake"); + LOG(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 suite is done + * (EOF or error). */ + transfer_data(client_socket, server_socket); - LOG(LOG_DEBUG, "client TLS handshake finished"); + LOG(LOG_DEBUG, "finished transferring data"); + + goto out; + } + /* server_certificate_path() may open the file, close it. */ + if (NULL != file) { + fclose(file); + } + } result = initialize_tls_session_server(server_socket, &server_session, &server_x509_cred); @@ -225,24 +228,75 @@ void handle_connection(int client_socket) { } server_session_started = 1; - LOG(LOG_DEBUG, "server TLS handshake finished, transferring data"); + LOG(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!"); + /* We send the error message over our TLS connection to the client, + * but with an invalid certificate. */ + 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 + * certificate was invalid */ + (validation_failed) ? "invalid" + : 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; + + /* 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); - /* FIXME: verify server's fingerprint */ + LOG(LOG_DEBUG, "starting client TLS handshake"); + + /* 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"); + + /* 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(LOG_DEBUG, "transferring TLS data"); /* 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"); + LOG(LOG_DEBUG, "finished transferring TLS data"); out: - /* Close TLS sessions if necessary. */ + /* 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_WR); + gnutls_bye(server_session, GNUTLS_SHUT_RDWR); } if (0 != client_session_started) { - gnutls_bye(client_session, GNUTLS_SHUT_WR); + gnutls_bye(client_session, GNUTLS_SHUT_RDWR); } if (0 != server_session_init) { gnutls_deinit(server_session); @@ -279,8 +333,13 @@ static int initialize_tls_session_client(int peer_socket, gnutls_session_t *session, gnutls_certificate_credentials_t *x509_cred) { int result; + int use_invalid_cert; char path[1024]; + /* 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 = 0 == strcmp(hostname, "invalid"); + /* Hostname too long. */ if (sizeof(path) - strlen(PROXY_SERVER_CERT_FORMAT) <= strlen(hostname)) { LOG(LOG_WARNING, @@ -307,24 +366,41 @@ gnutls_certificate_allocate_credentials(): %s", } /* 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 (!use_invalid_cert) { + result = gnutls_certificate_set_x509_trust_file(*x509_cred, + PROXY_CA_FILE, + GNUTLS_X509_FMT_PEM); + /* 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); + gnutls_certificate_free_credentials(*x509_cred); 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 (!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 (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)); + gnutls_certificate_free_credentials(*x509_cred); /* Could be a missing certificate. */ return -2; } @@ -336,6 +412,7 @@ can't read server certificate ('%s') or key file ('%s'): %s", 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); @@ -343,6 +420,8 @@ can't read server certificate ('%s') or key file ('%s'): %s", 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, @@ -351,6 +430,8 @@ 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; } @@ -377,6 +458,7 @@ 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); @@ -384,6 +466,8 @@ gnutls_certificate_allocate_credentials(): %s", 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, @@ -392,6 +476,8 @@ 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; } @@ -439,9 +525,12 @@ static void send_forwarding_failure(FILE *client_fd) { fprintf(client_fd, "HTTP/1.0 503 Forwarding failure\r\n"); fprintf(client_fd, "\r\n"); } +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); +} -#if 0 /* Transfer data between client and server sockets until one closes the * connection. */ static void transfer_data(int client, int server) { @@ -493,6 +582,8 @@ 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()"); @@ -516,7 +607,6 @@ 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. */