diff options
Diffstat (limited to '')
| -rw-r--r-- | src/tls.c | 1109 |
1 files changed, 1109 insertions, 0 deletions
diff --git a/src/tls.c b/src/tls.c new file mode 100644 index 0000000..a5f3501 --- /dev/null +++ b/src/tls.c @@ -0,0 +1,1109 @@ +/* + * Copyright (c) 2019, Redis Labs + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of Redis nor the names of its contributors may be used + * to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + + +#include "server.h" +#include "connhelpers.h" +#include "adlist.h" + +#ifdef USE_OPENSSL + +#include <openssl/conf.h> +#include <openssl/ssl.h> +#include <openssl/err.h> +#include <openssl/rand.h> +#include <openssl/pem.h> +#if OPENSSL_VERSION_NUMBER >= 0x30000000L +#include <openssl/decoder.h> +#endif +#include <sys/uio.h> + +#define REDIS_TLS_PROTO_TLSv1 (1<<0) +#define REDIS_TLS_PROTO_TLSv1_1 (1<<1) +#define REDIS_TLS_PROTO_TLSv1_2 (1<<2) +#define REDIS_TLS_PROTO_TLSv1_3 (1<<3) + +/* Use safe defaults */ +#ifdef TLS1_3_VERSION +#define REDIS_TLS_PROTO_DEFAULT (REDIS_TLS_PROTO_TLSv1_2|REDIS_TLS_PROTO_TLSv1_3) +#else +#define REDIS_TLS_PROTO_DEFAULT (REDIS_TLS_PROTO_TLSv1_2) +#endif + +extern ConnectionType CT_Socket; + +SSL_CTX *redis_tls_ctx = NULL; +SSL_CTX *redis_tls_client_ctx = NULL; + +static int parseProtocolsConfig(const char *str) { + int i, count = 0; + int protocols = 0; + + if (!str) return REDIS_TLS_PROTO_DEFAULT; + sds *tokens = sdssplitlen(str, strlen(str), " ", 1, &count); + + if (!tokens) { + serverLog(LL_WARNING, "Invalid tls-protocols configuration string"); + return -1; + } + for (i = 0; i < count; i++) { + if (!strcasecmp(tokens[i], "tlsv1")) protocols |= REDIS_TLS_PROTO_TLSv1; + else if (!strcasecmp(tokens[i], "tlsv1.1")) protocols |= REDIS_TLS_PROTO_TLSv1_1; + else if (!strcasecmp(tokens[i], "tlsv1.2")) protocols |= REDIS_TLS_PROTO_TLSv1_2; + else if (!strcasecmp(tokens[i], "tlsv1.3")) { +#ifdef TLS1_3_VERSION + protocols |= REDIS_TLS_PROTO_TLSv1_3; +#else + serverLog(LL_WARNING, "TLSv1.3 is specified in tls-protocols but not supported by OpenSSL."); + protocols = -1; + break; +#endif + } else { + serverLog(LL_WARNING, "Invalid tls-protocols specified. " + "Use a combination of 'TLSv1', 'TLSv1.1', 'TLSv1.2' and 'TLSv1.3'."); + protocols = -1; + break; + } + } + sdsfreesplitres(tokens, count); + + return protocols; +} + +/* list of connections with pending data already read from the socket, but not + * served to the reader yet. */ +static list *pending_list = NULL; + +/** + * OpenSSL global initialization and locking handling callbacks. + * Note that this is only required for OpenSSL < 1.1.0. + */ + +#if OPENSSL_VERSION_NUMBER < 0x10100000L +#define USE_CRYPTO_LOCKS +#endif + +#ifdef USE_CRYPTO_LOCKS + +static pthread_mutex_t *openssl_locks; + +static void sslLockingCallback(int mode, int lock_id, const char *f, int line) { + pthread_mutex_t *mt = openssl_locks + lock_id; + + if (mode & CRYPTO_LOCK) { + pthread_mutex_lock(mt); + } else { + pthread_mutex_unlock(mt); + } + + (void)f; + (void)line; +} + +static void initCryptoLocks(void) { + unsigned i, nlocks; + if (CRYPTO_get_locking_callback() != NULL) { + /* Someone already set the callback before us. Don't destroy it! */ + return; + } + nlocks = CRYPTO_num_locks(); + openssl_locks = zmalloc(sizeof(*openssl_locks) * nlocks); + for (i = 0; i < nlocks; i++) { + pthread_mutex_init(openssl_locks + i, NULL); + } + CRYPTO_set_locking_callback(sslLockingCallback); +} +#endif /* USE_CRYPTO_LOCKS */ + +void tlsInit(void) { + /* Enable configuring OpenSSL using the standard openssl.cnf + * OPENSSL_config()/OPENSSL_init_crypto() should be the first + * call to the OpenSSL* library. + * - OPENSSL_config() should be used for OpenSSL versions < 1.1.0 + * - OPENSSL_init_crypto() should be used for OpenSSL versions >= 1.1.0 + */ + #if OPENSSL_VERSION_NUMBER < 0x10100000L + OPENSSL_config(NULL); + SSL_load_error_strings(); + SSL_library_init(); + #elif OPENSSL_VERSION_NUMBER < 0x10101000L + OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL); + #else + OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG|OPENSSL_INIT_ATFORK, NULL); + #endif + +#ifdef USE_CRYPTO_LOCKS + initCryptoLocks(); +#endif + + if (!RAND_poll()) { + serverLog(LL_WARNING, "OpenSSL: Failed to seed random number generator."); + } + + pending_list = listCreate(); +} + +void tlsCleanup(void) { + if (redis_tls_ctx) { + SSL_CTX_free(redis_tls_ctx); + redis_tls_ctx = NULL; + } + if (redis_tls_client_ctx) { + SSL_CTX_free(redis_tls_client_ctx); + redis_tls_client_ctx = NULL; + } + + #if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER) + // unavailable on LibreSSL + OPENSSL_cleanup(); + #endif +} + +/* Callback for passing a keyfile password stored as an sds to OpenSSL */ +static int tlsPasswordCallback(char *buf, int size, int rwflag, void *u) { + UNUSED(rwflag); + + const char *pass = u; + size_t pass_len; + + if (!pass) return -1; + pass_len = strlen(pass); + if (pass_len > (size_t) size) return -1; + memcpy(buf, pass, pass_len); + + return (int) pass_len; +} + +/* Create a *base* SSL_CTX using the SSL configuration provided. The base context + * includes everything that's common for both client-side and server-side connections. + */ +static SSL_CTX *createSSLContext(redisTLSContextConfig *ctx_config, int protocols, int client) { + const char *cert_file = client ? ctx_config->client_cert_file : ctx_config->cert_file; + const char *key_file = client ? ctx_config->client_key_file : ctx_config->key_file; + const char *key_file_pass = client ? ctx_config->client_key_file_pass : ctx_config->key_file_pass; + char errbuf[256]; + SSL_CTX *ctx = NULL; + + ctx = SSL_CTX_new(SSLv23_method()); + + SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3); + +#ifdef SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS + SSL_CTX_set_options(ctx, SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS); +#endif + + if (!(protocols & REDIS_TLS_PROTO_TLSv1)) + SSL_CTX_set_options(ctx, SSL_OP_NO_TLSv1); + if (!(protocols & REDIS_TLS_PROTO_TLSv1_1)) + SSL_CTX_set_options(ctx, SSL_OP_NO_TLSv1_1); +#ifdef SSL_OP_NO_TLSv1_2 + if (!(protocols & REDIS_TLS_PROTO_TLSv1_2)) + SSL_CTX_set_options(ctx, SSL_OP_NO_TLSv1_2); +#endif +#ifdef SSL_OP_NO_TLSv1_3 + if (!(protocols & REDIS_TLS_PROTO_TLSv1_3)) + SSL_CTX_set_options(ctx, SSL_OP_NO_TLSv1_3); +#endif + +#ifdef SSL_OP_NO_COMPRESSION + SSL_CTX_set_options(ctx, SSL_OP_NO_COMPRESSION); +#endif + + SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE|SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER); + SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER|SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL); + + SSL_CTX_set_default_passwd_cb(ctx, tlsPasswordCallback); + SSL_CTX_set_default_passwd_cb_userdata(ctx, (void *) key_file_pass); + + if (SSL_CTX_use_certificate_chain_file(ctx, cert_file) <= 0) { + ERR_error_string_n(ERR_get_error(), errbuf, sizeof(errbuf)); + serverLog(LL_WARNING, "Failed to load certificate: %s: %s", cert_file, errbuf); + goto error; + } + + if (SSL_CTX_use_PrivateKey_file(ctx, key_file, SSL_FILETYPE_PEM) <= 0) { + ERR_error_string_n(ERR_get_error(), errbuf, sizeof(errbuf)); + serverLog(LL_WARNING, "Failed to load private key: %s: %s", key_file, errbuf); + goto error; + } + + if ((ctx_config->ca_cert_file || ctx_config->ca_cert_dir) && + SSL_CTX_load_verify_locations(ctx, ctx_config->ca_cert_file, ctx_config->ca_cert_dir) <= 0) { + ERR_error_string_n(ERR_get_error(), errbuf, sizeof(errbuf)); + serverLog(LL_WARNING, "Failed to configure CA certificate(s) file/directory: %s", errbuf); + goto error; + } + + if (ctx_config->ciphers && !SSL_CTX_set_cipher_list(ctx, ctx_config->ciphers)) { + serverLog(LL_WARNING, "Failed to configure ciphers: %s", ctx_config->ciphers); + goto error; + } + +#ifdef TLS1_3_VERSION + if (ctx_config->ciphersuites && !SSL_CTX_set_ciphersuites(ctx, ctx_config->ciphersuites)) { + serverLog(LL_WARNING, "Failed to configure ciphersuites: %s", ctx_config->ciphersuites); + goto error; + } +#endif + + return ctx; + +error: + if (ctx) SSL_CTX_free(ctx); + return NULL; +} + +/* Attempt to configure/reconfigure TLS. This operation is atomic and will + * leave the SSL_CTX unchanged if fails. + */ +int tlsConfigure(redisTLSContextConfig *ctx_config) { + char errbuf[256]; + SSL_CTX *ctx = NULL; + SSL_CTX *client_ctx = NULL; + + if (!ctx_config->cert_file) { + serverLog(LL_WARNING, "No tls-cert-file configured!"); + goto error; + } + + if (!ctx_config->key_file) { + serverLog(LL_WARNING, "No tls-key-file configured!"); + goto error; + } + + if (((server.tls_auth_clients != TLS_CLIENT_AUTH_NO) || server.tls_cluster || server.tls_replication) && + !ctx_config->ca_cert_file && !ctx_config->ca_cert_dir) { + serverLog(LL_WARNING, "Either tls-ca-cert-file or tls-ca-cert-dir must be specified when tls-cluster, tls-replication or tls-auth-clients are enabled!"); + goto error; + } + + int protocols = parseProtocolsConfig(ctx_config->protocols); + if (protocols == -1) goto error; + + /* Create server side/generla context */ + ctx = createSSLContext(ctx_config, protocols, 0); + if (!ctx) goto error; + + if (ctx_config->session_caching) { + SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_SERVER); + SSL_CTX_sess_set_cache_size(ctx, ctx_config->session_cache_size); + SSL_CTX_set_timeout(ctx, ctx_config->session_cache_timeout); + SSL_CTX_set_session_id_context(ctx, (void *) "redis", 5); + } else { + SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF); + } + +#ifdef SSL_OP_NO_CLIENT_RENEGOTIATION + SSL_CTX_set_options(ctx, SSL_OP_NO_CLIENT_RENEGOTIATION); +#endif + + if (ctx_config->prefer_server_ciphers) + SSL_CTX_set_options(ctx, SSL_OP_CIPHER_SERVER_PREFERENCE); + +#if ((OPENSSL_VERSION_NUMBER < 0x30000000L) && defined(SSL_CTX_set_ecdh_auto)) + SSL_CTX_set_ecdh_auto(ctx, 1); +#endif + SSL_CTX_set_options(ctx, SSL_OP_SINGLE_DH_USE); + + if (ctx_config->dh_params_file) { + FILE *dhfile = fopen(ctx_config->dh_params_file, "r"); + if (!dhfile) { + serverLog(LL_WARNING, "Failed to load %s: %s", ctx_config->dh_params_file, strerror(errno)); + goto error; + } + +#if (OPENSSL_VERSION_NUMBER >= 0x30000000L) + EVP_PKEY *pkey = NULL; + OSSL_DECODER_CTX *dctx = OSSL_DECODER_CTX_new_for_pkey( + &pkey, "PEM", NULL, "DH", OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS, NULL, NULL); + if (!dctx) { + serverLog(LL_WARNING, "No decoder for DH params."); + fclose(dhfile); + goto error; + } + if (!OSSL_DECODER_from_fp(dctx, dhfile)) { + serverLog(LL_WARNING, "%s: failed to read DH params.", ctx_config->dh_params_file); + OSSL_DECODER_CTX_free(dctx); + fclose(dhfile); + goto error; + } + + OSSL_DECODER_CTX_free(dctx); + fclose(dhfile); + + if (SSL_CTX_set0_tmp_dh_pkey(ctx, pkey) <= 0) { + ERR_error_string_n(ERR_get_error(), errbuf, sizeof(errbuf)); + serverLog(LL_WARNING, "Failed to load DH params file: %s: %s", ctx_config->dh_params_file, errbuf); + EVP_PKEY_free(pkey); + goto error; + } + /* Not freeing pkey, it is owned by OpenSSL now */ +#else + DH *dh = PEM_read_DHparams(dhfile, NULL, NULL, NULL); + fclose(dhfile); + if (!dh) { + serverLog(LL_WARNING, "%s: failed to read DH params.", ctx_config->dh_params_file); + goto error; + } + + if (SSL_CTX_set_tmp_dh(ctx, dh) <= 0) { + ERR_error_string_n(ERR_get_error(), errbuf, sizeof(errbuf)); + serverLog(LL_WARNING, "Failed to load DH params file: %s: %s", ctx_config->dh_params_file, errbuf); + DH_free(dh); + goto error; + } + + DH_free(dh); +#endif + } else { +#if (OPENSSL_VERSION_NUMBER >= 0x30000000L) + SSL_CTX_set_dh_auto(ctx, 1); +#endif + } + + /* If a client-side certificate is configured, create an explicit client context */ + if (ctx_config->client_cert_file && ctx_config->client_key_file) { + client_ctx = createSSLContext(ctx_config, protocols, 1); + if (!client_ctx) goto error; + } + + SSL_CTX_free(redis_tls_ctx); + SSL_CTX_free(redis_tls_client_ctx); + redis_tls_ctx = ctx; + redis_tls_client_ctx = client_ctx; + + return C_OK; + +error: + if (ctx) SSL_CTX_free(ctx); + if (client_ctx) SSL_CTX_free(client_ctx); + return C_ERR; +} + +/* Return 1 if TLS was already configured, 0 otherwise. + */ +int isTlsConfigured(void) { + return redis_tls_ctx != NULL; +} + +#ifdef TLS_DEBUGGING +#define TLSCONN_DEBUG(fmt, ...) \ + serverLog(LL_DEBUG, "TLSCONN: " fmt, __VA_ARGS__) +#else +#define TLSCONN_DEBUG(fmt, ...) +#endif + +ConnectionType CT_TLS; + +/* Normal socket connections have a simple events/handler correlation. + * + * With TLS connections we need to handle cases where during a logical read + * or write operation, the SSL library asks to block for the opposite + * socket operation. + * + * When this happens, we need to do two things: + * 1. Make sure we register for the event. + * 2. Make sure we know which handler needs to execute when the + * event fires. That is, if we notify the caller of a write operation + * that it blocks, and SSL asks for a read, we need to trigger the + * write handler again on the next read event. + * + */ + +typedef enum { + WANT_READ = 1, + WANT_WRITE +} WantIOType; + +#define TLS_CONN_FLAG_READ_WANT_WRITE (1<<0) +#define TLS_CONN_FLAG_WRITE_WANT_READ (1<<1) +#define TLS_CONN_FLAG_FD_SET (1<<2) + +typedef struct tls_connection { + connection c; + int flags; + SSL *ssl; + char *ssl_error; + listNode *pending_list_node; +} tls_connection; + +static connection *createTLSConnection(int client_side) { + SSL_CTX *ctx = redis_tls_ctx; + if (client_side && redis_tls_client_ctx) + ctx = redis_tls_client_ctx; + tls_connection *conn = zcalloc(sizeof(tls_connection)); + conn->c.type = &CT_TLS; + conn->c.fd = -1; + conn->ssl = SSL_new(ctx); + return (connection *) conn; +} + +connection *connCreateTLS(void) { + return createTLSConnection(1); +} + +/* Fetch the latest OpenSSL error and store it in the connection */ +static void updateTLSError(tls_connection *conn) { + conn->c.last_errno = 0; + if (conn->ssl_error) zfree(conn->ssl_error); + conn->ssl_error = zmalloc(512); + ERR_error_string_n(ERR_get_error(), conn->ssl_error, 512); +} + +/* Create a new TLS connection that is already associated with + * an accepted underlying file descriptor. + * + * The socket is not ready for I/O until connAccept() was called and + * invoked the connection-level accept handler. + * + * Callers should use connGetState() and verify the created connection + * is not in an error state. + */ +connection *connCreateAcceptedTLS(int fd, int require_auth) { + tls_connection *conn = (tls_connection *) createTLSConnection(0); + conn->c.fd = fd; + conn->c.state = CONN_STATE_ACCEPTING; + + if (!conn->ssl) { + updateTLSError(conn); + conn->c.state = CONN_STATE_ERROR; + return (connection *) conn; + } + + switch (require_auth) { + case TLS_CLIENT_AUTH_NO: + SSL_set_verify(conn->ssl, SSL_VERIFY_NONE, NULL); + break; + case TLS_CLIENT_AUTH_OPTIONAL: + SSL_set_verify(conn->ssl, SSL_VERIFY_PEER, NULL); + break; + default: /* TLS_CLIENT_AUTH_YES, also fall-secure */ + SSL_set_verify(conn->ssl, SSL_VERIFY_PEER|SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL); + break; + } + + SSL_set_fd(conn->ssl, conn->c.fd); + SSL_set_accept_state(conn->ssl); + + return (connection *) conn; +} + +static void tlsEventHandler(struct aeEventLoop *el, int fd, void *clientData, int mask); +static void updateSSLEvent(tls_connection *conn); + +/* Process the return code received from OpenSSL> + * Update the want parameter with expected I/O. + * Update the connection's error state if a real error has occurred. + * Returns an SSL error code, or 0 if no further handling is required. + */ +static int handleSSLReturnCode(tls_connection *conn, int ret_value, WantIOType *want) { + if (ret_value <= 0) { + int ssl_err = SSL_get_error(conn->ssl, ret_value); + switch (ssl_err) { + case SSL_ERROR_WANT_WRITE: + *want = WANT_WRITE; + return 0; + case SSL_ERROR_WANT_READ: + *want = WANT_READ; + return 0; + case SSL_ERROR_SYSCALL: + conn->c.last_errno = errno; + if (conn->ssl_error) zfree(conn->ssl_error); + conn->ssl_error = errno ? zstrdup(strerror(errno)) : NULL; + break; + default: + /* Error! */ + updateTLSError(conn); + break; + } + + return ssl_err; + } + + return 0; +} + +/* Handle OpenSSL return code following SSL_write() or SSL_read(): + * + * - Updates conn state and last_errno. + * - If update_event is nonzero, calls updateSSLEvent() when necessary. + * + * Returns ret_value, or -1 on error or dropped connection. + */ +static int updateStateAfterSSLIO(tls_connection *conn, int ret_value, int update_event) { + /* If system call was interrupted, there's no need to go through the full + * OpenSSL error handling and just report this for the caller to retry the + * operation. + */ + if (errno == EINTR) { + conn->c.last_errno = EINTR; + return -1; + } + + if (ret_value <= 0) { + WantIOType want = 0; + int ssl_err; + if (!(ssl_err = handleSSLReturnCode(conn, ret_value, &want))) { + if (want == WANT_READ) conn->flags |= TLS_CONN_FLAG_WRITE_WANT_READ; + if (want == WANT_WRITE) conn->flags |= TLS_CONN_FLAG_READ_WANT_WRITE; + if (update_event) updateSSLEvent(conn); + errno = EAGAIN; + return -1; + } else { + if (ssl_err == SSL_ERROR_ZERO_RETURN || + ((ssl_err == SSL_ERROR_SYSCALL && !errno))) { + conn->c.state = CONN_STATE_CLOSED; + return -1; + } else { + conn->c.state = CONN_STATE_ERROR; + return -1; + } + } + } + + return ret_value; +} + +static void registerSSLEvent(tls_connection *conn, WantIOType want) { + int mask = aeGetFileEvents(server.el, conn->c.fd); + + switch (want) { + case WANT_READ: + if (mask & AE_WRITABLE) aeDeleteFileEvent(server.el, conn->c.fd, AE_WRITABLE); + if (!(mask & AE_READABLE)) aeCreateFileEvent(server.el, conn->c.fd, AE_READABLE, + tlsEventHandler, conn); + break; + case WANT_WRITE: + if (mask & AE_READABLE) aeDeleteFileEvent(server.el, conn->c.fd, AE_READABLE); + if (!(mask & AE_WRITABLE)) aeCreateFileEvent(server.el, conn->c.fd, AE_WRITABLE, + tlsEventHandler, conn); + break; + default: + serverAssert(0); + break; + } +} + +void updateSSLEvent(tls_connection *conn) { + int mask = aeGetFileEvents(server.el, conn->c.fd); + int need_read = conn->c.read_handler || (conn->flags & TLS_CONN_FLAG_WRITE_WANT_READ); + int need_write = conn->c.write_handler || (conn->flags & TLS_CONN_FLAG_READ_WANT_WRITE); + + if (need_read && !(mask & AE_READABLE)) + aeCreateFileEvent(server.el, conn->c.fd, AE_READABLE, tlsEventHandler, conn); + if (!need_read && (mask & AE_READABLE)) + aeDeleteFileEvent(server.el, conn->c.fd, AE_READABLE); + + if (need_write && !(mask & AE_WRITABLE)) + aeCreateFileEvent(server.el, conn->c.fd, AE_WRITABLE, tlsEventHandler, conn); + if (!need_write && (mask & AE_WRITABLE)) + aeDeleteFileEvent(server.el, conn->c.fd, AE_WRITABLE); +} + +static void tlsHandleEvent(tls_connection *conn, int mask) { + int ret, conn_error; + + TLSCONN_DEBUG("tlsEventHandler(): fd=%d, state=%d, mask=%d, r=%d, w=%d, flags=%d", + fd, conn->c.state, mask, conn->c.read_handler != NULL, conn->c.write_handler != NULL, + conn->flags); + + ERR_clear_error(); + + switch (conn->c.state) { + case CONN_STATE_CONNECTING: + conn_error = connGetSocketError((connection *) conn); + if (conn_error) { + conn->c.last_errno = conn_error; + conn->c.state = CONN_STATE_ERROR; + } else { + if (!(conn->flags & TLS_CONN_FLAG_FD_SET)) { + SSL_set_fd(conn->ssl, conn->c.fd); + conn->flags |= TLS_CONN_FLAG_FD_SET; + } + ret = SSL_connect(conn->ssl); + if (ret <= 0) { + WantIOType want = 0; + if (!handleSSLReturnCode(conn, ret, &want)) { + registerSSLEvent(conn, want); + + /* Avoid hitting UpdateSSLEvent, which knows nothing + * of what SSL_connect() wants and instead looks at our + * R/W handlers. + */ + return; + } + + /* If not handled, it's an error */ + conn->c.state = CONN_STATE_ERROR; + } else { + conn->c.state = CONN_STATE_CONNECTED; + } + } + + if (!callHandler((connection *) conn, conn->c.conn_handler)) return; + conn->c.conn_handler = NULL; + break; + case CONN_STATE_ACCEPTING: + ret = SSL_accept(conn->ssl); + if (ret <= 0) { + WantIOType want = 0; + if (!handleSSLReturnCode(conn, ret, &want)) { + /* Avoid hitting UpdateSSLEvent, which knows nothing + * of what SSL_connect() wants and instead looks at our + * R/W handlers. + */ + registerSSLEvent(conn, want); + return; + } + + /* If not handled, it's an error */ + conn->c.state = CONN_STATE_ERROR; + } else { + conn->c.state = CONN_STATE_CONNECTED; + } + + if (!callHandler((connection *) conn, conn->c.conn_handler)) return; + conn->c.conn_handler = NULL; + break; + case CONN_STATE_CONNECTED: + { + int call_read = ((mask & AE_READABLE) && conn->c.read_handler) || + ((mask & AE_WRITABLE) && (conn->flags & TLS_CONN_FLAG_READ_WANT_WRITE)); + int call_write = ((mask & AE_WRITABLE) && conn->c.write_handler) || + ((mask & AE_READABLE) && (conn->flags & TLS_CONN_FLAG_WRITE_WANT_READ)); + + /* Normally we execute the readable event first, and the writable + * event laster. This is useful as sometimes we may be able + * to serve the reply of a query immediately after processing the + * query. + * + * However if WRITE_BARRIER is set in the mask, our application is + * asking us to do the reverse: never fire the writable event + * after the readable. In such a case, we invert the calls. + * This is useful when, for instance, we want to do things + * in the beforeSleep() hook, like fsynching a file to disk, + * before replying to a client. */ + int invert = conn->c.flags & CONN_FLAG_WRITE_BARRIER; + + if (!invert && call_read) { + conn->flags &= ~TLS_CONN_FLAG_READ_WANT_WRITE; + if (!callHandler((connection *) conn, conn->c.read_handler)) return; + } + + /* Fire the writable event. */ + if (call_write) { + conn->flags &= ~TLS_CONN_FLAG_WRITE_WANT_READ; + if (!callHandler((connection *) conn, conn->c.write_handler)) return; + } + + /* If we have to invert the call, fire the readable event now + * after the writable one. */ + if (invert && call_read) { + conn->flags &= ~TLS_CONN_FLAG_READ_WANT_WRITE; + if (!callHandler((connection *) conn, conn->c.read_handler)) return; + } + + /* If SSL has pending that, already read from the socket, we're at + * risk of not calling the read handler again, make sure to add it + * to a list of pending connection that should be handled anyway. */ + if ((mask & AE_READABLE)) { + if (SSL_pending(conn->ssl) > 0) { + if (!conn->pending_list_node) { + listAddNodeTail(pending_list, conn); + conn->pending_list_node = listLast(pending_list); + } + } else if (conn->pending_list_node) { + listDelNode(pending_list, conn->pending_list_node); + conn->pending_list_node = NULL; + } + } + + break; + } + default: + break; + } + + updateSSLEvent(conn); +} + +static void tlsEventHandler(struct aeEventLoop *el, int fd, void *clientData, int mask) { + UNUSED(el); + UNUSED(fd); + tls_connection *conn = clientData; + tlsHandleEvent(conn, mask); +} + +static void connTLSClose(connection *conn_) { + tls_connection *conn = (tls_connection *) conn_; + + if (conn->ssl) { + if (conn->c.state == CONN_STATE_CONNECTED) + SSL_shutdown(conn->ssl); + SSL_free(conn->ssl); + conn->ssl = NULL; + } + + if (conn->ssl_error) { + zfree(conn->ssl_error); + conn->ssl_error = NULL; + } + + if (conn->pending_list_node) { + listDelNode(pending_list, conn->pending_list_node); + conn->pending_list_node = NULL; + } + + CT_Socket.close(conn_); +} + +static int connTLSAccept(connection *_conn, ConnectionCallbackFunc accept_handler) { + tls_connection *conn = (tls_connection *) _conn; + int ret; + + if (conn->c.state != CONN_STATE_ACCEPTING) return C_ERR; + ERR_clear_error(); + + /* Try to accept */ + conn->c.conn_handler = accept_handler; + ret = SSL_accept(conn->ssl); + + if (ret <= 0) { + WantIOType want = 0; + if (!handleSSLReturnCode(conn, ret, &want)) { + registerSSLEvent(conn, want); /* We'll fire back */ + return C_OK; + } else { + conn->c.state = CONN_STATE_ERROR; + return C_ERR; + } + } + + conn->c.state = CONN_STATE_CONNECTED; + if (!callHandler((connection *) conn, conn->c.conn_handler)) return C_OK; + conn->c.conn_handler = NULL; + + return C_OK; +} + +static int connTLSConnect(connection *conn_, const char *addr, int port, const char *src_addr, ConnectionCallbackFunc connect_handler) { + tls_connection *conn = (tls_connection *) conn_; + + if (conn->c.state != CONN_STATE_NONE) return C_ERR; + ERR_clear_error(); + + /* Initiate Socket connection first */ + if (CT_Socket.connect(conn_, addr, port, src_addr, connect_handler) == C_ERR) return C_ERR; + + /* Return now, once the socket is connected we'll initiate + * TLS connection from the event handler. + */ + return C_OK; +} + +static int connTLSWrite(connection *conn_, const void *data, size_t data_len) { + tls_connection *conn = (tls_connection *) conn_; + int ret; + + if (conn->c.state != CONN_STATE_CONNECTED) return -1; + ERR_clear_error(); + ret = SSL_write(conn->ssl, data, data_len); + return updateStateAfterSSLIO(conn, ret, 1); +} + +static int connTLSWritev(connection *conn_, const struct iovec *iov, int iovcnt) { + if (iovcnt == 1) return connTLSWrite(conn_, iov[0].iov_base, iov[0].iov_len); + + /* Accumulate the amount of bytes of each buffer and check if it exceeds NET_MAX_WRITES_PER_EVENT. */ + size_t iov_bytes_len = 0; + for (int i = 0; i < iovcnt; i++) { + iov_bytes_len += iov[i].iov_len; + if (iov_bytes_len > NET_MAX_WRITES_PER_EVENT) break; + } + + /* The amount of all buffers is greater than NET_MAX_WRITES_PER_EVENT, + * which is not worth doing so much memory copying to reduce system calls, + * therefore, invoke connTLSWrite() multiple times to avoid memory copies. */ + if (iov_bytes_len > NET_MAX_WRITES_PER_EVENT) { + ssize_t tot_sent = 0; + for (int i = 0; i < iovcnt; i++) { + ssize_t sent = connTLSWrite(conn_, iov[i].iov_base, iov[i].iov_len); + if (sent <= 0) return tot_sent > 0 ? tot_sent : sent; + tot_sent += sent; + if ((size_t) sent != iov[i].iov_len) break; + } + return tot_sent; + } + + /* The amount of all buffers is less than NET_MAX_WRITES_PER_EVENT, + * which is worth doing more memory copies in exchange for fewer system calls, + * so concatenate these scattered buffers into a contiguous piece of memory + * and send it away by one call to connTLSWrite(). */ + char buf[iov_bytes_len]; + size_t offset = 0; + for (int i = 0; i < iovcnt; i++) { + memcpy(buf + offset, iov[i].iov_base, iov[i].iov_len); + offset += iov[i].iov_len; + } + return connTLSWrite(conn_, buf, iov_bytes_len); +} + +static int connTLSRead(connection *conn_, void *buf, size_t buf_len) { + tls_connection *conn = (tls_connection *) conn_; + int ret; + + if (conn->c.state != CONN_STATE_CONNECTED) return -1; + ERR_clear_error(); + ret = SSL_read(conn->ssl, buf, buf_len); + return updateStateAfterSSLIO(conn, ret, 1); +} + +static const char *connTLSGetLastError(connection *conn_) { + tls_connection *conn = (tls_connection *) conn_; + + if (conn->ssl_error) return conn->ssl_error; + return NULL; +} + +int connTLSSetWriteHandler(connection *conn, ConnectionCallbackFunc func, int barrier) { + conn->write_handler = func; + if (barrier) + conn->flags |= CONN_FLAG_WRITE_BARRIER; + else + conn->flags &= ~CONN_FLAG_WRITE_BARRIER; + updateSSLEvent((tls_connection *) conn); + return C_OK; +} + +int connTLSSetReadHandler(connection *conn, ConnectionCallbackFunc func) { + conn->read_handler = func; + updateSSLEvent((tls_connection *) conn); + return C_OK; +} + +static void setBlockingTimeout(tls_connection *conn, long long timeout) { + anetBlock(NULL, conn->c.fd); + anetSendTimeout(NULL, conn->c.fd, timeout); + anetRecvTimeout(NULL, conn->c.fd, timeout); +} + +static void unsetBlockingTimeout(tls_connection *conn) { + anetNonBlock(NULL, conn->c.fd); + anetSendTimeout(NULL, conn->c.fd, 0); + anetRecvTimeout(NULL, conn->c.fd, 0); +} + +static int connTLSBlockingConnect(connection *conn_, const char *addr, int port, long long timeout) { + tls_connection *conn = (tls_connection *) conn_; + int ret; + + if (conn->c.state != CONN_STATE_NONE) return C_ERR; + + /* Initiate socket blocking connect first */ + if (CT_Socket.blocking_connect(conn_, addr, port, timeout) == C_ERR) return C_ERR; + + /* Initiate TLS connection now. We set up a send/recv timeout on the socket, + * which means the specified timeout will not be enforced accurately. */ + SSL_set_fd(conn->ssl, conn->c.fd); + setBlockingTimeout(conn, timeout); + + if ((ret = SSL_connect(conn->ssl)) <= 0) { + conn->c.state = CONN_STATE_ERROR; + return C_ERR; + } + unsetBlockingTimeout(conn); + + conn->c.state = CONN_STATE_CONNECTED; + return C_OK; +} + +static ssize_t connTLSSyncWrite(connection *conn_, char *ptr, ssize_t size, long long timeout) { + tls_connection *conn = (tls_connection *) conn_; + + setBlockingTimeout(conn, timeout); + SSL_clear_mode(conn->ssl, SSL_MODE_ENABLE_PARTIAL_WRITE); + ERR_clear_error(); + int ret = SSL_write(conn->ssl, ptr, size); + ret = updateStateAfterSSLIO(conn, ret, 0); + SSL_set_mode(conn->ssl, SSL_MODE_ENABLE_PARTIAL_WRITE); + unsetBlockingTimeout(conn); + + return ret; +} + +static ssize_t connTLSSyncRead(connection *conn_, char *ptr, ssize_t size, long long timeout) { + tls_connection *conn = (tls_connection *) conn_; + + setBlockingTimeout(conn, timeout); + ERR_clear_error(); + int ret = SSL_read(conn->ssl, ptr, size); + ret = updateStateAfterSSLIO(conn, ret, 0); + unsetBlockingTimeout(conn); + + return ret; +} + +static ssize_t connTLSSyncReadLine(connection *conn_, char *ptr, ssize_t size, long long timeout) { + tls_connection *conn = (tls_connection *) conn_; + ssize_t nread = 0; + + setBlockingTimeout(conn, timeout); + + size--; + while(size) { + char c; + + ERR_clear_error(); + int ret = SSL_read(conn->ssl, &c, 1); + ret = updateStateAfterSSLIO(conn, ret, 0); + if (ret <= 0) { + nread = -1; + goto exit; + } + if (c == '\n') { + *ptr = '\0'; + if (nread && *(ptr-1) == '\r') *(ptr-1) = '\0'; + goto exit; + } else { + *ptr++ = c; + *ptr = '\0'; + nread++; + } + size--; + } +exit: + unsetBlockingTimeout(conn); + return nread; +} + +static int connTLSGetType(connection *conn_) { + (void) conn_; + + return CONN_TYPE_TLS; +} + +ConnectionType CT_TLS = { + .ae_handler = tlsEventHandler, + .accept = connTLSAccept, + .connect = connTLSConnect, + .blocking_connect = connTLSBlockingConnect, + .read = connTLSRead, + .write = connTLSWrite, + .writev = connTLSWritev, + .close = connTLSClose, + .set_write_handler = connTLSSetWriteHandler, + .set_read_handler = connTLSSetReadHandler, + .get_last_error = connTLSGetLastError, + .sync_write = connTLSSyncWrite, + .sync_read = connTLSSyncRead, + .sync_readline = connTLSSyncReadLine, + .get_type = connTLSGetType +}; + +int tlsHasPendingData() { + if (!pending_list) + return 0; + return listLength(pending_list) > 0; +} + +int tlsProcessPendingData() { + listIter li; + listNode *ln; + + int processed = listLength(pending_list); + listRewind(pending_list,&li); + while((ln = listNext(&li))) { + tls_connection *conn = listNodeValue(ln); + tlsHandleEvent(conn, AE_READABLE); + } + return processed; +} + +/* Fetch the peer certificate used for authentication on the specified + * connection and return it as a PEM-encoded sds. + */ +sds connTLSGetPeerCert(connection *conn_) { + tls_connection *conn = (tls_connection *) conn_; + if (conn_->type->get_type(conn_) != CONN_TYPE_TLS || !conn->ssl) return NULL; + + X509 *cert = SSL_get_peer_certificate(conn->ssl); + if (!cert) return NULL; + + BIO *bio = BIO_new(BIO_s_mem()); + if (bio == NULL || !PEM_write_bio_X509(bio, cert)) { + if (bio != NULL) BIO_free(bio); + return NULL; + } + + const char *bio_ptr; + long long bio_len = BIO_get_mem_data(bio, &bio_ptr); + sds cert_pem = sdsnewlen(bio_ptr, bio_len); + BIO_free(bio); + + return cert_pem; +} + +#else /* USE_OPENSSL */ + +void tlsInit(void) { +} + +void tlsCleanup(void) { +} + +int tlsConfigure(redisTLSContextConfig *ctx_config) { + UNUSED(ctx_config); + return C_OK; +} + +connection *connCreateTLS(void) { + return NULL; +} + +connection *connCreateAcceptedTLS(int fd, int require_auth) { + UNUSED(fd); + UNUSED(require_auth); + + return NULL; +} + +int tlsHasPendingData() { + return 0; +} + +int tlsProcessPendingData() { + return 0; +} + +sds connTLSGetPeerCert(connection *conn_) { + (void) conn_; + return NULL; +} + +#endif |