#include "../libnetdata.h" #ifdef ENABLE_HTTPS SSL_CTX *netdata_ssl_exporting_ctx =NULL; SSL_CTX *netdata_ssl_streaming_sender_ctx =NULL; SSL_CTX *netdata_ssl_web_server_ctx =NULL; const char *netdata_ssl_security_key =NULL; const char *netdata_ssl_security_cert =NULL; const char *tls_version=NULL; const char *tls_ciphers=NULL; bool netdata_ssl_validate_certificate = true; bool netdata_ssl_validate_certificate_sender = true; static SOCKET_PEERS netdata_ssl_peers(NETDATA_SSL *ssl) { int sock_fd; if(unlikely(!ssl->conn)) sock_fd = -1; else sock_fd = SSL_get_rfd(ssl->conn); return socket_peers(sock_fd); } bool netdata_ssl_open(NETDATA_SSL *ssl, SSL_CTX *ctx, int fd) { errno = 0; ssl->ssl_errno = 0; if(ssl->conn) { if(!ctx || SSL_get_SSL_CTX(ssl->conn) != ctx) { SSL_free(ssl->conn); ssl->conn = NULL; } else if (SSL_clear(ssl->conn) == 0) { netdata_ssl_log_error_queue("SSL_clear", ssl); SSL_free(ssl->conn); ssl->conn = NULL; } } if(!ssl->conn) { if(!ctx) { internal_error(true, "SSL: not CTX given"); ssl->state = NETDATA_SSL_STATE_FAILED; return false; } ssl->conn = SSL_new(ctx); if (!ssl->conn) { netdata_ssl_log_error_queue("SSL_new", ssl); ssl->state = NETDATA_SSL_STATE_FAILED; return false; } } if(SSL_set_fd(ssl->conn, fd) != 1) { netdata_ssl_log_error_queue("SSL_set_fd", ssl); ssl->state = NETDATA_SSL_STATE_FAILED; return false; } ssl->state = NETDATA_SSL_STATE_INIT; ERR_clear_error(); return true; } void netdata_ssl_close(NETDATA_SSL *ssl) { errno = 0; ssl->ssl_errno = 0; if(ssl->conn) { if(SSL_connection(ssl)) { int ret = SSL_shutdown(ssl->conn); if(ret == 0) SSL_shutdown(ssl->conn); } SSL_free(ssl->conn); ERR_clear_error(); } *ssl = NETDATA_SSL_UNSET_CONNECTION; } void netdata_ssl_log_error_queue(const char *call, NETDATA_SSL *ssl) { error_limit_static_thread_var(erl, 1, 0); unsigned long err; while((err = ERR_get_error())) { char *code; switch (err) { case SSL_ERROR_NONE: code = "SSL_ERROR_NONE"; break; case SSL_ERROR_SSL: code = "SSL_ERROR_SSL"; ssl->state = NETDATA_SSL_STATE_FAILED; break; case SSL_ERROR_WANT_READ: code = "SSL_ERROR_WANT_READ"; break; case SSL_ERROR_WANT_WRITE: code = "SSL_ERROR_WANT_WRITE"; break; case SSL_ERROR_WANT_X509_LOOKUP: code = "SSL_ERROR_WANT_X509_LOOKUP"; break; case SSL_ERROR_SYSCALL: code = "SSL_ERROR_SYSCALL"; ssl->state = NETDATA_SSL_STATE_FAILED; break; case SSL_ERROR_ZERO_RETURN: code = "SSL_ERROR_ZERO_RETURN"; break; case SSL_ERROR_WANT_CONNECT: code = "SSL_ERROR_WANT_CONNECT"; break; case SSL_ERROR_WANT_ACCEPT: code = "SSL_ERROR_WANT_ACCEPT"; break; #ifdef SSL_ERROR_WANT_ASYNC case SSL_ERROR_WANT_ASYNC: code = "SSL_ERROR_WANT_ASYNC"; break; #endif #ifdef SSL_ERROR_WANT_ASYNC_JOB case SSL_ERROR_WANT_ASYNC_JOB: code = "SSL_ERROR_WANT_ASYNC_JOB"; break; #endif #ifdef SSL_ERROR_WANT_CLIENT_HELLO_CB case SSL_ERROR_WANT_CLIENT_HELLO_CB: code = "SSL_ERROR_WANT_CLIENT_HELLO_CB"; break; #endif #ifdef SSL_ERROR_WANT_RETRY_VERIFY case SSL_ERROR_WANT_RETRY_VERIFY: code = "SSL_ERROR_WANT_RETRY_VERIFY"; break; #endif default: code = "SSL_ERROR_UNKNOWN"; break; } char str[1024 + 1]; ERR_error_string_n(err, str, 1024); str[1024] = '\0'; SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: %s() on socket local [[%s]:%d] <-> remote [[%s]:%d], returned error %lu (%s): %s", call, peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, err, code, str); } } static inline bool is_handshake_complete(NETDATA_SSL *ssl, const char *op) { error_limit_static_thread_var(erl, 1, 0); if(unlikely(!ssl->conn)) { internal_error(true, "SSL: trying to %s on a NULL connection", op); return false; } switch(ssl->state) { case NETDATA_SSL_STATE_NOT_SSL: { SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: on socket local [[%s]:%d] <-> remote [[%s]:%d], attempt to %s on non-SSL connection", peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, op); return false; } case NETDATA_SSL_STATE_INIT: { SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: on socket local [[%s]:%d] <-> remote [[%s]:%d], attempt to %s on an incomplete connection", peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, op); return false; } case NETDATA_SSL_STATE_FAILED: { SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: on socket local [[%s]:%d] <-> remote [[%s]:%d], attempt to %s on a failed connection", peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, op); return false; } case NETDATA_SSL_STATE_COMPLETE: { return true; } } return false; } /* * netdata_ssl_read() should return the same as read(): * * Positive value: The read() function succeeded and read some bytes. The exact number of bytes read is returned. * * Zero: For files and sockets, a return value of zero signifies end-of-file (EOF), meaning no more data is available * for reading. For sockets, this usually means the other side has closed the connection. * * -1: An error occurred. The specific error can be found by examining the errno variable. * EAGAIN or EWOULDBLOCK: The file descriptor is in non-blocking mode, and the read operation would block. * (These are often the same value, but can be different on some systems.) */ ssize_t netdata_ssl_read(NETDATA_SSL *ssl, void *buf, size_t num) { errno = 0; ssl->ssl_errno = 0; if(unlikely(!is_handshake_complete(ssl, "read"))) return -1; int bytes = SSL_read(ssl->conn, buf, (int)num); if(unlikely(bytes <= 0)) { int err = SSL_get_error(ssl->conn, bytes); netdata_ssl_log_error_queue("SSL_read", ssl); if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE) { ssl->ssl_errno = err; errno = EWOULDBLOCK; } bytes = -1; // according to read() or recv() } return bytes; } /* * netdata_ssl_write() should return the same as write(): * * Positive value: The write() function succeeded and wrote some bytes. The exact number of bytes written is returned. * * Zero: It's technically possible for write() to return zero, indicating that zero bytes were written. However, for a * socket, this generally does not happen unless the size of the data to be written is zero. * * -1: An error occurred. The specific error can be found by examining the errno variable. * EAGAIN or EWOULDBLOCK: The file descriptor is in non-blocking mode, and the write operation would block. * (These are often the same value, but can be different on some systems.) */ ssize_t netdata_ssl_write(NETDATA_SSL *ssl, const void *buf, size_t num) { errno = 0; ssl->ssl_errno = 0; if(unlikely(!is_handshake_complete(ssl, "write"))) return -1; int bytes = SSL_write(ssl->conn, (uint8_t *)buf, (int)num); if(unlikely(bytes <= 0)) { int err = SSL_get_error(ssl->conn, bytes); netdata_ssl_log_error_queue("SSL_write", ssl); if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE) { ssl->ssl_errno = err; errno = EWOULDBLOCK; } bytes = -1; // according to write() or send() } return bytes; } static inline bool is_handshake_initialized(NETDATA_SSL *ssl, const char *op) { error_limit_static_thread_var(erl, 1, 0); if(unlikely(!ssl->conn)) { internal_error(true, "SSL: trying to %s on a NULL connection", op); return false; } switch(ssl->state) { case NETDATA_SSL_STATE_NOT_SSL: { SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: on socket local [[%s]:%d] <-> remote [[%s]:%d], attempt to %s on non-SSL connection", peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, op); return false; } case NETDATA_SSL_STATE_INIT: { return true; } case NETDATA_SSL_STATE_FAILED: { SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: on socket local [[%s]:%d] <-> remote [[%s]:%d], attempt to %s on a failed connection", peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, op); return false; } case NETDATA_SSL_STATE_COMPLETE: { SOCKET_PEERS peers = netdata_ssl_peers(ssl); error_limit(&erl, "SSL: on socket local [[%s]:%d] <-> remote [[%s]:%d], attempt to %s on an complete connection", peers.local.ip, peers.local.port, peers.peer.ip, peers.peer.port, op); return false; } } return false; } #define WANT_READ_WRITE_TIMEOUT_MS 10 static inline bool want_read_write_should_retry(NETDATA_SSL *ssl, int err) { int ssl_errno = SSL_get_error(ssl->conn, err); if(ssl_errno == SSL_ERROR_WANT_READ || ssl_errno == SSL_ERROR_WANT_WRITE) { struct pollfd pfds[1] = { [0] = { .fd = SSL_get_rfd(ssl->conn), .events = (short)(((ssl_errno == SSL_ERROR_WANT_READ ) ? POLLIN : 0) | ((ssl_errno == SSL_ERROR_WANT_WRITE) ? POLLOUT : 0)), }}; if(poll(pfds, 1, WANT_READ_WRITE_TIMEOUT_MS) <= 0) return false; // timeout (0) or error (<0) return true; // we have activity, so we should retry } return false; // an unknown error } bool netdata_ssl_connect(NETDATA_SSL *ssl) { errno = 0; ssl->ssl_errno = 0; if(unlikely(!is_handshake_initialized(ssl, "connect"))) return false; SSL_set_connect_state(ssl->conn); int err; while ((err = SSL_connect(ssl->conn)) != 1) { if(!want_read_write_should_retry(ssl, err)) break; } if (err != 1) { netdata_ssl_log_error_queue("SSL_connect", ssl); ssl->state = NETDATA_SSL_STATE_FAILED; return false; } ssl->state = NETDATA_SSL_STATE_COMPLETE; return true; } bool netdata_ssl_accept(NETDATA_SSL *ssl) { errno = 0; ssl->ssl_errno = 0; if(unlikely(!is_handshake_initialized(ssl, "accept"))) return false; SSL_set_accept_state(ssl->conn); int err; while ((err = SSL_accept(ssl->conn)) != 1) { if(!want_read_write_should_retry(ssl, err)) break; } if (err != 1) { netdata_ssl_log_error_queue("SSL_accept", ssl); ssl->state = NETDATA_SSL_STATE_FAILED; return false; } ssl->state = NETDATA_SSL_STATE_COMPLETE; return true; } /** * Info Callback * * Function used as callback for the OpenSSL Library * * @param ssl a pointer to the SSL structure of the client * @param where the variable with the flags set. * @param ret the return of the caller */ static void netdata_ssl_info_callback(const SSL *ssl, int where, int ret __maybe_unused) { (void)ssl; if (where & SSL_CB_ALERT) { debug(D_WEB_CLIENT,"SSL INFO CALLBACK %s %s", SSL_alert_type_string(ret), SSL_alert_desc_string_long(ret)); } } /** * OpenSSL Library * * Starts the openssl library for the Netdata. */ void netdata_ssl_initialize_openssl() { #if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110 # if (SSLEAY_VERSION_NUMBER >= OPENSSL_VERSION_097) OPENSSL_config(NULL); # endif SSL_load_error_strings(); SSL_library_init(); #else if (OPENSSL_init_ssl(OPENSSL_INIT_LOAD_CONFIG, NULL) != 1) { error("SSL library cannot be initialized."); } #endif } #if OPENSSL_VERSION_NUMBER >= OPENSSL_VERSION_110 /** * TLS version * * Returns the TLS version depending of the user input. * * @param lversion is the user input. * * @return it returns the version number. */ static int netdata_ssl_select_tls_version(const char *lversion) { if (!strcmp(lversion, "1") || !strcmp(lversion, "1.0")) return TLS1_VERSION; else if (!strcmp(lversion, "1.1")) return TLS1_1_VERSION; else if (!strcmp(lversion, "1.2")) return TLS1_2_VERSION; #if defined(TLS1_3_VERSION) else if (!strcmp(lversion, "1.3")) return TLS1_3_VERSION; #endif #if defined(TLS_MAX_VERSION) return TLS_MAX_VERSION; #else return TLS1_2_VERSION; #endif } #endif /** * Initialize Openssl Client * * Starts the client context with TLS 1.2. * * @return It returns the context on success or NULL otherwise */ SSL_CTX * netdata_ssl_create_client_ctx(unsigned long mode) { SSL_CTX *ctx; #if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110 ctx = SSL_CTX_new(SSLv23_client_method()); #else ctx = SSL_CTX_new(TLS_client_method()); #endif if(ctx) { #if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110 SSL_CTX_set_options (ctx,SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3|SSL_OP_NO_COMPRESSION); #else SSL_CTX_set_min_proto_version(ctx, TLS1_VERSION); # if defined(TLS_MAX_VERSION) SSL_CTX_set_max_proto_version(ctx, TLS_MAX_VERSION); # elif defined(TLS1_3_VERSION) SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION); # elif defined(TLS1_2_VERSION) SSL_CTX_set_max_proto_version(ctx, TLS1_2_VERSION); # endif #endif } if(mode) SSL_CTX_set_mode(ctx, mode); return ctx; } /** * Initialize OpenSSL server * * Starts the server context with TLS 1.2 and load the certificate. * * @return It returns the context on success or NULL otherwise */ static SSL_CTX * netdata_ssl_create_server_ctx(unsigned long mode) { SSL_CTX *ctx; char lerror[512]; static int netdata_id_context = 1; //TO DO: Confirm the necessity to check return for other OPENSSL function #if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110 ctx = SSL_CTX_new(SSLv23_server_method()); if (!ctx) { error("Cannot create a new SSL context, netdata won't encrypt communication"); return NULL; } SSL_CTX_use_certificate_file(ctx, netdata_ssl_security_cert, SSL_FILETYPE_PEM); #else ctx = SSL_CTX_new(TLS_server_method()); if (!ctx) { error("Cannot create a new SSL context, netdata won't encrypt communication"); return NULL; } SSL_CTX_use_certificate_chain_file(ctx, netdata_ssl_security_cert); #endif #if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110 SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3|SSL_OP_NO_COMPRESSION); #else SSL_CTX_set_min_proto_version(ctx, TLS1_VERSION); SSL_CTX_set_max_proto_version(ctx, netdata_ssl_select_tls_version(tls_version)); if(tls_ciphers && strcmp(tls_ciphers, "none") != 0) { if (!SSL_CTX_set_cipher_list(ctx, tls_ciphers)) { error("SSL error. cannot set the cipher list"); } } #endif SSL_CTX_use_PrivateKey_file(ctx, netdata_ssl_security_key,SSL_FILETYPE_PEM); if (!SSL_CTX_check_private_key(ctx)) { ERR_error_string_n(ERR_get_error(),lerror,sizeof(lerror)); error("SSL cannot check the private key: %s",lerror); SSL_CTX_free(ctx); return NULL; } SSL_CTX_set_session_id_context(ctx,(void*)&netdata_id_context,(unsigned int)sizeof(netdata_id_context)); SSL_CTX_set_info_callback(ctx, netdata_ssl_info_callback); #if (OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_095) SSL_CTX_set_verify_depth(ctx,1); #endif debug(D_WEB_CLIENT,"SSL GLOBAL CONTEXT STARTED\n"); SSL_CTX_set_mode(ctx, mode); return ctx; } /** * Start SSL * * Call the correct function to start the SSL context. * * @param selector informs the context that must be initialized, the following list has the valid values: * NETDATA_SSL_CONTEXT_SERVER - the server context * NETDATA_SSL_CONTEXT_STREAMING - Starts the streaming context. * NETDATA_SSL_CONTEXT_EXPORTING - Starts the OpenTSDB context */ void netdata_ssl_initialize_ctx(int selector) { static SPINLOCK sp = NETDATA_SPINLOCK_INITIALIZER; netdata_spinlock_lock(&sp); switch (selector) { case NETDATA_SSL_WEB_SERVER_CTX: { if(!netdata_ssl_web_server_ctx) { struct stat statbuf; if (stat(netdata_ssl_security_key, &statbuf) || stat(netdata_ssl_security_cert, &statbuf)) info("To use encryption it is necessary to set \"ssl certificate\" and \"ssl key\" in [web] !\n"); else { netdata_ssl_web_server_ctx = netdata_ssl_create_server_ctx( SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | // SSL_MODE_AUTO_RETRY | 0); if(netdata_ssl_web_server_ctx && !netdata_ssl_validate_certificate) SSL_CTX_set_verify(netdata_ssl_web_server_ctx, SSL_VERIFY_NONE, NULL); } } break; } case NETDATA_SSL_STREAMING_SENDER_CTX: { if(!netdata_ssl_streaming_sender_ctx) { //This is necessary for the stream, because it is working sometimes with nonblock socket. //It returns the bitmask after to change, there is not any description of errors in the documentation netdata_ssl_streaming_sender_ctx = netdata_ssl_create_client_ctx( SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | // SSL_MODE_AUTO_RETRY | 0 ); if(netdata_ssl_streaming_sender_ctx && !netdata_ssl_validate_certificate_sender) SSL_CTX_set_verify(netdata_ssl_streaming_sender_ctx, SSL_VERIFY_NONE, NULL); } break; } case NETDATA_SSL_EXPORTING_CTX: { if(!netdata_ssl_exporting_ctx) { netdata_ssl_exporting_ctx = netdata_ssl_create_client_ctx(0); if(netdata_ssl_exporting_ctx && !netdata_ssl_validate_certificate) SSL_CTX_set_verify(netdata_ssl_exporting_ctx, SSL_VERIFY_NONE, NULL); } break; } } netdata_spinlock_unlock(&sp); } /** * Clean Open SSL * * Clean all the allocated contexts from netdata. */ void netdata_ssl_cleanup() { if (netdata_ssl_web_server_ctx) { SSL_CTX_free(netdata_ssl_web_server_ctx); netdata_ssl_web_server_ctx = NULL; } if (netdata_ssl_streaming_sender_ctx) { SSL_CTX_free(netdata_ssl_streaming_sender_ctx); netdata_ssl_streaming_sender_ctx = NULL; } if (netdata_ssl_exporting_ctx) { SSL_CTX_free(netdata_ssl_exporting_ctx); netdata_ssl_exporting_ctx = NULL; } #if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110 ERR_free_strings(); #endif } /** * Test Certificate * * Check the certificate of Netdata parent * * @param ssl is the connection structure * * @return It returns 0 on success and -1 otherwise */ int security_test_certificate(SSL *ssl) { X509* cert = SSL_get_peer_certificate(ssl); int ret; long status; if (!cert) { return -1; } status = SSL_get_verify_result(ssl); if((X509_V_OK != status)) { char error[512]; ERR_error_string_n(ERR_get_error(), error, sizeof(error)); error("SSL RFC4158 check: We have a invalid certificate, the tests result with %ld and message %s", status, error); ret = -1; } else { ret = 0; } return ret; } /** * Location for context * * Case the user give us a directory with the certificates available and * the Netdata parent certificate, we use this function to validate the certificate. * * @param ctx the context where the path will be set. * @param file the file with Netdata parent certificate. * @param path the directory where the certificates are stored. * * @return It returns 0 on success and -1 otherwise. */ int ssl_security_location_for_context(SSL_CTX *ctx, char *file, char *path) { int load_custom = 1, load_default = 1; if (file || path) { if(!SSL_CTX_load_verify_locations(ctx, file, path)) { info("Netdata can not verify custom CAfile or CApath for parent's SSL certificate, so it will use the default OpenSSL configuration to validate certificates!"); load_custom = 0; } } if(!SSL_CTX_set_default_verify_paths(ctx)) { info("Can not verify default OpenSSL configuration to validate certificates!"); load_default = 0; } if (load_custom == 0 && load_default == 0) return -1; return 0; } #endif