diff options
Diffstat (limited to 'plugins/sudoers/log_client.c')
| -rw-r--r-- | plugins/sudoers/log_client.c | 2102 |
1 files changed, 2102 insertions, 0 deletions
diff --git a/plugins/sudoers/log_client.c b/plugins/sudoers/log_client.c new file mode 100644 index 0000000..94f3b0b --- /dev/null +++ b/plugins/sudoers/log_client.c @@ -0,0 +1,2102 @@ +/* + * SPDX-License-Identifier: ISC + * + * Copyright (c) 2019-2022 Todd C. Miller <Todd.Miller@sudo.ws> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * This is an open source non-commercial project. Dear PVS-Studio, please check it. + * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com + */ + +#include <config.h> + +#ifdef SUDOERS_LOG_CLIENT + +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/wait.h> +#include <netinet/in.h> +#include <netinet/tcp.h> +#include <arpa/inet.h> + +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <netdb.h> +#if defined(HAVE_STDINT_H) +# include <stdint.h> +#elif defined(HAVE_INTTYPES_H) +# include <inttypes.h> +#endif +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <unistd.h> +#include <pwd.h> +#include <grp.h> +#ifndef HAVE_GETADDRINFO +# include <compat/getaddrinfo.h> +#endif + +#if defined(HAVE_OPENSSL) +# if defined(HAVE_WOLFSSL) +# include <wolfssl/options.h> +# endif +# include <openssl/ssl.h> +# include <openssl/err.h> +# include <openssl/x509v3.h> +#endif /* HAVE_OPENSSL */ + +#define NEED_INET_NTOP /* to expose sudo_inet_ntop in sudo_compat.h */ + +#include <sudoers.h> +#include <sudo_event.h> +#include <sudo_eventlog.h> +#include <sudo_iolog.h> +#include <hostcheck.h> +#include <log_client.h> +#include <strlist.h> + +/* Shared between iolog.c and audit.c */ +struct client_closure *client_closure; + +/* Server callback may redirect to client callback for TLS. */ +static void client_msg_cb(int fd, int what, void *v); +static void server_msg_cb(int fd, int what, void *v); + +static void +connect_cb(int sock, int what, void *v) +{ + int optval, ret, *errnump = v; + socklen_t optlen = sizeof(optval); + debug_decl(connect_cb, SUDOERS_DEBUG_UTIL); + + if (what == SUDO_PLUGIN_EV_TIMEOUT) { + *errnump = ETIMEDOUT; + } else { + ret = getsockopt(sock, SOL_SOCKET, SO_ERROR, &optval, &optlen); + *errnump = ret == 0 ? optval : errno; + } + + debug_return; +} + +/* + * Like connect(2) but with a timeout. + */ +static int +timed_connect(int sock, const struct sockaddr *addr, socklen_t addrlen, + const struct timespec *timeout) +{ + struct sudo_event_base *evbase = NULL; + struct sudo_event *connect_event = NULL; + int ret, errnum = 0; + debug_decl(timed_connect, SUDOERS_DEBUG_UTIL); + + ret = connect(sock, addr, addrlen); + if (ret == -1 && errno == EINPROGRESS) { + evbase = sudo_ev_base_alloc(); + connect_event = sudo_ev_alloc(sock, SUDO_PLUGIN_EV_WRITE, connect_cb, + &errnum); + if (evbase == NULL || connect_event == NULL) { + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + if (sudo_ev_add(evbase, connect_event, timeout, false) == -1) { + sudo_warnx("%s", U_("unable to add event to queue")); + goto done; + } + if (sudo_ev_dispatch(evbase) == -1) { + sudo_warn("%s", U_("error in event loop")); + goto done; + } + if (errnum == 0) + ret = 0; + else + errno = errnum; + } + +done: + sudo_ev_base_free(evbase); + sudo_ev_free(connect_event); + + debug_return_int(ret); +} + +#if defined(HAVE_OPENSSL) +static int +verify_peer_identity(int preverify_ok, X509_STORE_CTX *ctx) +{ + HostnameValidationResult result; + struct client_closure *closure; + SSL *ssl; + X509 *current_cert; + X509 *peer_cert; + debug_decl(verify_peer_identity, SUDOERS_DEBUG_UTIL); + + /* if pre-verification of the cert failed, just propagate that result back */ + if (preverify_ok != 1) { + debug_return_int(0); + } + + /* since this callback is called for each cert in the chain, + * check that current cert is the peer's certificate + */ + current_cert = X509_STORE_CTX_get_current_cert(ctx); + peer_cert = X509_STORE_CTX_get0_cert(ctx); + + if (current_cert != peer_cert) { + debug_return_int(1); + } + + /* read out the attached object (closure) from the ssl connection object */ + ssl = X509_STORE_CTX_get_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx()); + closure = SSL_get_ex_data(ssl, 1); + + result = validate_hostname(peer_cert, closure->server_name, + closure->server_ip, 0); + + switch(result) + { + case MatchFound: + debug_return_int(1); + default: + debug_return_int(0); + } +} + +static bool +tls_init(struct client_closure *closure) +{ + const char *errstr; + debug_decl(tls_init, SUDOERS_DEBUG_PLUGIN); + + /* Only attempt to initialize TLS once, the parameters don't change. */ + if (closure->ssl_initialized) { + if (closure->ssl == NULL) + debug_return_bool(false); + SSL_clear(closure->ssl); + debug_return_bool(true); + } + + closure->ssl_initialized = true; + SSL_library_init(); + OpenSSL_add_all_algorithms(); + SSL_load_error_strings(); + + /* Create the ssl context and enforce TLS 1.2 or higher. */ + if ((closure->ssl_ctx = SSL_CTX_new(TLS_method())) == NULL) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("Creation of new SSL_CTX object failed: %s"), + errstr ? errstr : strerror(errno)); + goto bad; + } +#ifdef HAVE_SSL_CTX_SET_MIN_PROTO_VERSION + if (!SSL_CTX_set_min_proto_version(closure->ssl_ctx, TLS1_2_VERSION)) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "unable to restrict min. protocol version: %s", + errstr ? errstr : strerror(errno)); + goto bad; + } +#else + SSL_CTX_set_options(closure->ssl_ctx, + SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3|SSL_OP_NO_TLSv1|SSL_OP_NO_TLSv1_1); +#endif + + /* Enable server cert verification if log_server_verify is set in sudoers */ + if (closure->log_details->verify_server) { + if (closure->log_details->ca_bundle != NULL) { + if (SSL_CTX_load_verify_locations(closure->ssl_ctx, + closure->log_details->ca_bundle, NULL) <= 0) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("%s: %s"), closure->log_details->ca_bundle, + errstr ? errstr : strerror(errno)); + sudo_warnx(U_("unable to load certificate authority bundle %s"), + closure->log_details->ca_bundle); + goto bad; + } + } else { + if (!SSL_CTX_set_default_verify_paths(closure->ssl_ctx)) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx("SSL_CTX_set_default_verify_paths: %s", + errstr ? errstr : strerror(errno)); + goto bad; + } + } + SSL_CTX_set_verify(closure->ssl_ctx, SSL_VERIFY_PEER, verify_peer_identity); + } + + /* Load the client certificate file if it is set in sudoers. */ + if (closure->log_details->cert_file != NULL) { + if (!SSL_CTX_use_certificate_chain_file(closure->ssl_ctx, + closure->log_details->cert_file)) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("%s: %s"), closure->log_details->cert_file, + errstr ? errstr : strerror(errno)); + sudo_warnx(U_("unable to load certificate %s"), + closure->log_details->cert_file); + goto bad; + } + if (closure->log_details->key_file == NULL) { + /* No explicit key file set, try to use the cert file. */ + closure->log_details->key_file = closure->log_details->cert_file; + } + if (!SSL_CTX_use_PrivateKey_file(closure->ssl_ctx, + closure->log_details->key_file, SSL_FILETYPE_PEM) || + !SSL_CTX_check_private_key(closure->ssl_ctx)) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("%s: %s"), closure->log_details->key_file, + errstr ? errstr : strerror(errno)); + sudo_warnx(U_("unable to load private key %s"), + closure->log_details->key_file); + goto bad; + } + } + + /* Create the SSL object and attach the closure. */ + if ((closure->ssl = SSL_new(closure->ssl_ctx)) == NULL) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("Unable to allocate ssl object: %s"), + errstr ? errstr : strerror(errno)); + goto bad; + } + if (SSL_set_ex_data(closure->ssl, 1, closure) <= 0) { + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("Unable to attach user data to the ssl object: %s"), + errstr ? errstr : strerror(errno)); + goto bad; + } + + debug_return_bool(true); + +bad: + SSL_free(closure->ssl); + closure->ssl = NULL; + SSL_CTX_free(closure->ssl_ctx); + closure->ssl_ctx = NULL; + debug_return_bool(false); +} + +struct tls_connect_closure { + bool tls_conn_status; + SSL *ssl; + const char *host; + const char *port; + const struct timespec *timeout; + struct sudo_event_base *evbase; + struct sudo_event *tls_connect_ev; +}; + +static void +tls_connect_cb(int sock, int what, void *v) +{ + struct tls_connect_closure *closure = v; + const struct timespec *timeout = closure->timeout; + int tls_con; + debug_decl(tls_connect_cb, SUDOERS_DEBUG_UTIL); + + if (what == SUDO_PLUGIN_EV_TIMEOUT) { + sudo_warnx("%s", U_("TLS handshake timeout occurred")); + goto bad; + } + + tls_con = SSL_connect(closure->ssl); + + if (tls_con == 1) { + sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO, + "TLS version: %s, negotiated cipher suite: %s", + SSL_get_version(closure->ssl), SSL_get_cipher(closure->ssl)); + closure->tls_conn_status = true; + } else { + const char *errstr; + + switch (SSL_get_error(closure->ssl, tls_con)) { + /* TLS handshake is not finished, reschedule event */ + case SSL_ERROR_WANT_READ: + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "SSL_connect returns SSL_ERROR_WANT_READ"); + if (what != SUDO_EV_READ) { + if (sudo_ev_set(closure->tls_connect_ev, sock, + SUDO_EV_READ, tls_connect_cb, closure) == -1) { + sudo_warnx("%s", U_("unable to set event")); + goto bad; + } + } + if (sudo_ev_add(closure->evbase, closure->tls_connect_ev, + timeout, false) == -1) { + sudo_warnx("%s", U_("unable to add event to queue")); + goto bad; + } + break; + case SSL_ERROR_WANT_WRITE: + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "SSL_connect returns SSL_ERROR_WANT_WRITE"); + if (what != SUDO_EV_WRITE) { + if (sudo_ev_set(closure->tls_connect_ev, sock, + SUDO_EV_WRITE, tls_connect_cb, closure) == -1) { + sudo_warnx("%s", U_("unable to set event")); + goto bad; + } + } + if (sudo_ev_add(closure->evbase, closure->tls_connect_ev, + timeout, false) == -1) { + sudo_warnx("%s", U_("unable to add event to queue")); + goto bad; + } + break; + case SSL_ERROR_SYSCALL: + sudo_warnx(U_("TLS connection to %s:%s failed: %s"), + closure->host, closure->port, strerror(errno)); + goto bad; + default: + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx(U_("TLS connection to %s:%s failed: %s"), + closure->host, closure->port, + errstr ? errstr : strerror(errno)); + goto bad; + } + } + + debug_return; + +bad: + /* Break out of tls connect event loop with an error. */ + sudo_ev_loopbreak(closure->evbase); + + debug_return; +} + +static bool +tls_timed_connect(SSL *ssl, const char *host, const char *port, + const struct timespec *timeout) +{ + struct tls_connect_closure closure; + debug_decl(tls_timed_connect, SUDOERS_DEBUG_UTIL); + + memset(&closure, 0, sizeof(closure)); + closure.ssl = ssl; + closure.host = host; + closure.port = port; + closure.timeout = timeout; + closure.evbase = sudo_ev_base_alloc(); + closure.tls_connect_ev = sudo_ev_alloc(SSL_get_fd(ssl), + SUDO_PLUGIN_EV_WRITE, tls_connect_cb, &closure); + + if (closure.evbase == NULL || closure.tls_connect_ev == NULL) { + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + + if (sudo_ev_add(closure.evbase, closure.tls_connect_ev, timeout, false) == -1) { + sudo_warnx("%s", U_("unable to add event to queue")); + goto done; + } + + if (sudo_ev_dispatch(closure.evbase) == -1) { + sudo_warnx("%s", U_("error in event loop")); + goto done; + } + +done: + if (closure.tls_connect_ev != NULL) + sudo_ev_free(closure.tls_connect_ev); + sudo_ev_base_free(closure.evbase); + + debug_return_bool(closure.tls_conn_status); +} +#endif /* HAVE_OPENSSL */ + +/* + * Connect to specified host:port + * If host has multiple addresses, the first one that connects is used. + * Returns open socket or -1 on error. + */ +static int +connect_server(const char *host, const char *port, bool tls, + struct client_closure *closure, const char **reason) +{ + const struct timespec *timeout = &closure->log_details->server_timeout; + struct addrinfo hints, *res, *res0; + const char *addr, *cause = NULL; + int error, sock = -1; + debug_decl(connect_server, SUDOERS_DEBUG_UTIL); + +#if !defined(HAVE_OPENSSL) + if (tls) { + errno = EPROTONOSUPPORT; + sudo_warn("%s:%s(tls)", host, port); + debug_return_int(-1); + } +#endif + + memset(&hints, 0, sizeof(hints)); + hints.ai_family = AF_UNSPEC; + hints.ai_socktype = SOCK_STREAM; + error = getaddrinfo(host, port, &hints, &res0); + if (error != 0) { + sudo_warnx(U_("unable to look up %s:%s: %s"), host, port, + gai_strerror(error)); + debug_return_int(-1); + } + + for (res = res0; res; res = res->ai_next) { + int flags, save_errno; + + sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol); + if (sock == -1) { + cause = "socket"; + continue; + } + flags = fcntl(sock, F_GETFL, 0); + if (flags == -1 || fcntl(sock, F_SETFL, flags | O_NONBLOCK) == -1) { + cause = "fcntl(O_NONBLOCK)"; + save_errno = errno; + close(sock); + errno = save_errno; + sock = -1; + continue; + } + if (fcntl(sock, F_SETFD, FD_CLOEXEC) == -1) { + cause = "fcntl(FD_CLOEXEC)"; + save_errno = errno; + close(sock); + errno = save_errno; + sock = -1; + continue; + } + if (closure->log_details->keepalive) { + flags = 1; + if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, &flags, + sizeof(flags)) == -1) { + cause = "setsockopt(SO_KEEPALIVE)"; + save_errno = errno; + close(sock); + errno = save_errno; + sock = -1; + continue; + } + } + if (timed_connect(sock, res->ai_addr, res->ai_addrlen, timeout) == -1) { + /* No need to set cause, caller's error message is sufficient. */ + save_errno = errno; + close(sock); + errno = save_errno; + sock = -1; + continue; + } + switch (res->ai_family) { + case AF_INET: + addr = (char *)&((struct sockaddr_in *)res->ai_addr)->sin_addr; + break; +#ifdef HAVE_STRUCT_IN6_ADDR + case AF_INET6: + addr = (char *)&((struct sockaddr_in6 *)res->ai_addr)->sin6_addr; + break; +#endif + default: + cause = "ai_family"; + save_errno = EAFNOSUPPORT; + shutdown(sock, SHUT_RDWR); + close(sock); + errno = save_errno; + sock = -1; + continue; + } + if (inet_ntop(res->ai_family, addr, closure->server_ip, + sizeof(closure->server_ip)) == NULL) { + cause = "inet_ntop"; + save_errno = errno; + shutdown(sock, SHUT_RDWR); + close(sock); + errno = save_errno; + sock = -1; + continue; + } + free(closure->server_name); + if ((closure->server_name = strdup(host)) == NULL) { + cause = "strdup"; + save_errno = errno; + shutdown(sock, SHUT_RDWR); + close(sock); + errno = save_errno; + sock = -1; + continue; + } + +#if defined(HAVE_OPENSSL) + if (tls) { + if (!tls_init(closure) || !SSL_set_fd(closure->ssl, sock)) { + cause = U_("TLS initialization was unsuccessful"); + save_errno = errno; + shutdown(sock, SHUT_RDWR); + close(sock); + errno = save_errno; + sock = -1; + continue; + } + /* Perform TLS handshake. */ + if (!tls_timed_connect(closure->ssl, host, port, timeout)) { + cause = U_("TLS handshake was unsuccessful"); + save_errno = errno; + shutdown(sock, SHUT_RDWR); + close(sock); + errno = save_errno; + sock = -1; + continue; + } + } else { + /* No TLS for this connection, make sure it is not initialized. */ + SSL_free(closure->ssl); + closure->ssl = NULL; + SSL_CTX_free(closure->ssl_ctx); + closure->ssl_ctx = NULL; + } +#endif /* HAVE_OPENSSL */ + break; /* success */ + } + freeaddrinfo(res0); + + if (sock == -1) + *reason = cause; + + debug_return_int(sock); +} + +/* + * Connect to the first server in the list. + * Stores socket in closure with O_NONBLOCK and close-on-exec flags set. + * Returns true on success, else false. + */ +bool +log_server_connect(struct client_closure *closure) +{ + struct sudoers_string *server; + char *host, *port, *copy = NULL; + const char *cause = NULL; + int sock; + bool tls, ret = false; + debug_decl(log_server_connect, SUDOERS_DEBUG_UTIL); + + STAILQ_FOREACH(server, closure->log_details->log_servers, entries) { + free(copy); + if ((copy = strdup(server->str)) == NULL) + break; + if (!iolog_parse_host_port(copy, &host, &port, &tls, DEFAULT_PORT, + DEFAULT_PORT_TLS)) { + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "unable to parse %s", copy); + continue; + } + sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO, + "connecting to %s port %s%s", host, port, tls ? " (tls)" : ""); + sock = connect_server(host, port, tls, closure, &cause); + if (sock != -1) { + if (closure->read_ev->set(closure->read_ev, sock, + SUDO_PLUGIN_EV_READ|SUDO_PLUGIN_EV_PERSIST, + server_msg_cb, closure) == -1) { + cause = (U_("unable to add event to queue")); + break; + } + + if (closure->write_ev->set(closure->write_ev, sock, + SUDO_PLUGIN_EV_WRITE|SUDO_PLUGIN_EV_PERSIST, + client_msg_cb, closure) == -1) { + cause = (U_("unable to add event to queue")); + break; + } + + /* success */ + closure->sock = sock; + ret = true; + break; + } + } + free(copy); + + if (!ret && cause != NULL) + sudo_warn("%s", cause); + + debug_return_bool(ret); +} + +/* + * Free client closure and contents, not including log details. + */ +void +client_closure_free(struct client_closure *closure) +{ + struct connection_buffer *buf; + debug_decl(client_closure_free, SUDOERS_DEBUG_UTIL); + + if (closure == NULL) + debug_return; + +#if defined(HAVE_OPENSSL) + /* Shut down the TLS connection cleanly and free SSL data. */ + if (closure->ssl != NULL) { + if (SSL_shutdown(closure->ssl) == 0) + SSL_shutdown(closure->ssl); + SSL_free(closure->ssl); + } + SSL_CTX_free(closure->ssl_ctx); +#endif + + if (closure->sock != -1) { + shutdown(closure->sock, SHUT_RDWR); + close(closure->sock); + } + free(closure->server_name); + while ((buf = TAILQ_FIRST(&closure->write_bufs)) != NULL) { + TAILQ_REMOVE(&closure->write_bufs, buf, entries); + free(buf->data); + free(buf); + } + while ((buf = TAILQ_FIRST(&closure->free_bufs)) != NULL) { + TAILQ_REMOVE(&closure->free_bufs, buf, entries); + free(buf->data); + free(buf); + } + if (closure->read_ev != NULL) + closure->read_ev->free(closure->read_ev); + if (closure->write_ev != NULL) + closure->write_ev->free(closure->write_ev); + free(closure->read_buf.data); + free(closure->iolog_id); + + free(closure); + + debug_return; +} + +static struct connection_buffer * +get_free_buf(struct client_closure *closure) +{ + struct connection_buffer *buf; + debug_decl(get_free_buf, SUDOERS_DEBUG_UTIL); + + buf = TAILQ_FIRST(&closure->free_bufs); + if (buf != NULL) + TAILQ_REMOVE(&closure->free_bufs, buf, entries); + else + buf = calloc(1, sizeof(*buf)); + + debug_return_ptr(buf); +} + +/* + * Format a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_client_message(struct client_closure *closure, ClientMessage *msg) +{ + struct connection_buffer *buf; + uint32_t msg_len; + bool ret = false; + size_t len; + debug_decl(fmt_client_message, SUDOERS_DEBUG_UTIL); + + if ((buf = get_free_buf(closure)) == NULL) { + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + + len = client_message__get_packed_size(msg); + if (len > MESSAGE_SIZE_MAX) { + sudo_warnx(U_("client message too large: %zu"), len); + goto done; + } + /* Wire message size is used for length encoding, precedes message. */ + msg_len = htonl((uint32_t)len); + len += sizeof(msg_len); + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: new ClientMessage, %zu bytes", + __func__, len); + + /* Resize buffer as needed. */ + if (len > buf->size) { + const size_t new_size = sudo_pow2_roundup(len); + if (new_size < len) { + /* overflow */ + errno = ENOMEM; + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + free(buf->data); + if ((buf->data = malloc(new_size)) == NULL) { + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + buf->size = new_size; + } + + memcpy(buf->data, &msg_len, sizeof(msg_len)); + client_message__pack(msg, buf->data + sizeof(msg_len)); + buf->len = len; + TAILQ_INSERT_TAIL(&closure->write_bufs, buf, entries); + buf = NULL; + + ret = true; + +done: + if (buf != NULL) { + free(buf->data); + free(buf); + } + debug_return_bool(ret); +} + +/* + * Build and format a ClientHello wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +static bool +fmt_client_hello(struct client_closure *closure) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + ClientHello hello_msg = CLIENT_HELLO__INIT; + bool ret = false; + debug_decl(fmt_client_hello, SUDOERS_DEBUG_UTIL); + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: sending ClientHello", __func__); + + /* Client name + version */ + hello_msg.client_id = (char *)"sudoers " PACKAGE_VERSION; + + /* Schedule ClientMessage */ + client_msg.u.hello_msg = &hello_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_HELLO_MSG; + ret = fmt_client_message(closure, &client_msg); + + debug_return_bool(ret); +} + +/* + * Free an array of InfoMessage. + * Does not free the actual contents, other than strlistval arrays. + */ +static void +free_info_messages(InfoMessage **info_msgs, size_t n) +{ + debug_decl(free_info_messages, SUDOERS_DEBUG_UTIL); + + if (info_msgs != NULL) { + while (n-- != 0) { + /* A strlist array is dynamically allocated. */ + if (info_msgs[n]->value_case == INFO_MESSAGE__VALUE_STRLISTVAL) { + free(info_msgs[n]->u.strlistval); + } + free(info_msgs[n]); + } + free(info_msgs); + } + + debug_return; +} + +static InfoMessage ** +fmt_info_messages(struct client_closure *closure, struct eventlog *evlog, + size_t *n_info_msgs) +{ + InfoMessage__StringList *runargv = NULL; + InfoMessage__StringList *runenv = NULL; + InfoMessage__StringList *submitenv = NULL; + InfoMessage **info_msgs = NULL; + size_t info_msgs_size, n = 0; + debug_decl(fmt_info_messages, SUDOERS_DEBUG_UTIL); + + /* Convert NULL-terminated vectors to StringList. */ + if (evlog->submitenv != NULL) { + if ((submitenv = malloc(sizeof(*submitenv))) == NULL) + goto bad; + info_message__string_list__init(submitenv); + submitenv->strings = evlog->submitenv; + while (submitenv->strings[submitenv->n_strings] != NULL) + submitenv->n_strings++; + } + + if (evlog->runargv != NULL) { + if ((runargv = malloc(sizeof(*runargv))) == NULL) + goto bad; + info_message__string_list__init(runargv); + runargv->strings = evlog->runargv; + while (runargv->strings[runargv->n_strings] != NULL) + runargv->n_strings++; + } + + if (evlog->runenv != NULL) { + if ((runenv = malloc(sizeof(*runenv))) == NULL) + goto bad; + info_message__string_list__init(runenv); + runenv->strings = evlog->runenv; + while (runenv->strings[runenv->n_strings] != NULL) + runenv->n_strings++; + } + + /* XXX - realloc as needed instead of preallocating */ + info_msgs_size = 24; + info_msgs = calloc(info_msgs_size, sizeof(InfoMessage *)); + if (info_msgs == NULL) + goto bad; + for (n = 0; n < info_msgs_size; n++) { + info_msgs[n] = malloc(sizeof(InfoMessage)); + if (info_msgs[n] == NULL) + goto bad; + info_message__init(info_msgs[n]); + } + +#define fill_str(_n, _v) do { \ + info_msgs[n]->key = (char *)(_n); \ + info_msgs[n]->u.strval = (_v); \ + info_msgs[n]->value_case = INFO_MESSAGE__VALUE_STRVAL; \ + n++; \ +} while (0) + +#define fill_strlist(_n, _v) do { \ + info_msgs[n]->key = (char *)(_n); \ + info_msgs[n]->u.strlistval = (_v); \ + info_msgs[n]->value_case = INFO_MESSAGE__VALUE_STRLISTVAL; \ + n++; \ +} while (0) + +#define fill_num(_n, _v) do { \ + info_msgs[n]->key = (char *)(_n); \ + info_msgs[n]->u.numval = (_v); \ + info_msgs[n]->value_case = INFO_MESSAGE__VALUE_NUMVAL; \ + n++; \ +} while (0) + + /* Fill in info_msgs */ + n = 0; + + /* TODO: clientargv (not currently supported by API) */ + /* TODO: clientpid */ + /* TODO: clientppid */ + /* TODO: clientsid */ + fill_num("columns", evlog->columns); + fill_str("command", evlog->command); + fill_num("lines", evlog->lines); + if (runargv != NULL) { + fill_strlist("runargv", runargv); + runargv = NULL; + } + if (evlog->runchroot != NULL) { + fill_str("runchroot", evlog->runchroot); + } + if (evlog->runcwd != NULL) { + fill_str("runcwd", evlog->runcwd); + } + if (runenv != NULL) { + fill_strlist("runenv", runenv); + runenv = NULL; + } + if (evlog->rungroup != NULL) { + fill_num("rungid", evlog->rungid); + fill_str("rungroup", evlog->rungroup); + } + /* TODO - rungids */ + /* TODO - rungroups */ + fill_num("runuid", evlog->runuid); + fill_str("runuser", evlog->runuser); + if (evlog->source != NULL) { + fill_str("source", evlog->source); + } + if (evlog->cwd != NULL) { + fill_str("submitcwd", evlog->cwd); + } + if (submitenv != NULL) { + fill_strlist("submitenv", submitenv); + submitenv = NULL; + } + /* TODO - submitgid */ + /* TODO - submitgids */ + /* TODO - submitgroup */ + /* TODO - submitgroups */ + fill_str("submithost", evlog->submithost); + /* TODO - submituid */ + fill_str("submituser", evlog->submituser); + if (evlog->ttyname != NULL) { + fill_str("ttyname", evlog->ttyname); + } + + /* Free unused structs. */ + while (info_msgs_size > n) + free(info_msgs[--info_msgs_size]); + + *n_info_msgs = n; + debug_return_ptr(info_msgs); + +bad: + free_info_messages(info_msgs, n); + free(runargv); + free(runenv); + free(submitenv); + + *n_info_msgs = 0; + debug_return_ptr(NULL); +} + +/* + * Build and format an AcceptMessage wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_accept_message(struct client_closure *closure, struct eventlog *evlog) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + AcceptMessage accept_msg = ACCEPT_MESSAGE__INIT; + TimeSpec ts = TIME_SPEC__INIT; + struct timespec now; + bool ret = false; + debug_decl(fmt_accept_message, SUDOERS_DEBUG_UTIL); + + /* + * Fill in AcceptMessage and add it to ClientMessage. + */ + if (sudo_gettime_real(&now)) { + sudo_warn("%s", U_("unable to get time of day")); + debug_return_bool(false); + } + ts.tv_sec = (int64_t)now.tv_sec; + ts.tv_nsec = (int32_t)now.tv_nsec; + accept_msg.submit_time = &ts; + + /* Client will send IoBuffer messages. */ + accept_msg.expect_iobufs = closure->log_io; + + accept_msg.info_msgs = fmt_info_messages(closure, evlog, + &accept_msg.n_info_msgs); + if (accept_msg.info_msgs == NULL) + goto done; + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending AcceptMessage, array length %zu", __func__, + accept_msg.n_info_msgs); + + /* Schedule ClientMessage */ + client_msg.u.accept_msg = &accept_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_ACCEPT_MSG; + ret = fmt_client_message(closure, &client_msg); + +done: + free_info_messages(accept_msg.info_msgs, accept_msg.n_info_msgs); + + debug_return_bool(ret); +} + +/* + * Build and format a RejectMessage wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_reject_message(struct client_closure *closure, struct eventlog *evlog) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + RejectMessage reject_msg = REJECT_MESSAGE__INIT; + TimeSpec ts = TIME_SPEC__INIT; + struct timespec now; + bool ret = false; + debug_decl(fmt_reject_message, SUDOERS_DEBUG_UTIL); + + /* + * Fill in RejectMessage and add it to ClientMessage. + */ + if (sudo_gettime_real(&now)) { + sudo_warn("%s", U_("unable to get time of day")); + debug_return_bool(false); + } + ts.tv_sec = (int64_t)now.tv_sec; + ts.tv_nsec = (int32_t)now.tv_nsec; + reject_msg.submit_time = &ts; + + /* Reason for rejecting the request. */ + reject_msg.reason = (char *)closure->reason; + + reject_msg.info_msgs = fmt_info_messages(closure, evlog, + &reject_msg.n_info_msgs); + if (reject_msg.info_msgs == NULL) + goto done; + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending RejectMessage, array length %zu", __func__, + reject_msg.n_info_msgs); + + /* Schedule ClientMessage */ + client_msg.u.reject_msg = &reject_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_REJECT_MSG; + ret = fmt_client_message(closure, &client_msg); + +done: + free_info_messages(reject_msg.info_msgs, reject_msg.n_info_msgs); + + debug_return_bool(ret); +} + +/* + * Build and format an AlertMessage wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +static bool +fmt_alert_message(struct client_closure *closure, struct eventlog *evlog) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + AlertMessage alert_msg = ALERT_MESSAGE__INIT; + TimeSpec ts = TIME_SPEC__INIT; + struct timespec now; + bool ret = false; + debug_decl(fmt_alert_message, SUDOERS_DEBUG_UTIL); + + /* + * Fill in AlertMessage and add it to ClientMessage. + */ + if (sudo_gettime_real(&now)) { + sudo_warn("%s", U_("unable to get time of day")); + debug_return_bool(false); + } + ts.tv_sec = (int64_t)now.tv_sec; + ts.tv_nsec = (int32_t)now.tv_nsec; + alert_msg.alert_time = &ts; + + /* Reason for the alert. */ + alert_msg.reason = (char *)closure->reason; + + alert_msg.info_msgs = fmt_info_messages(closure, evlog, + &alert_msg.n_info_msgs); + if (alert_msg.info_msgs == NULL) + goto done; + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending AlertMessage, array length %zu", __func__, + alert_msg.n_info_msgs); + + /* Schedule ClientMessage */ + client_msg.u.alert_msg = &alert_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_ALERT_MSG; + ret = fmt_client_message(closure, &client_msg); + +done: + free_info_messages(alert_msg.info_msgs, alert_msg.n_info_msgs); + + debug_return_bool(ret); +} + +/* + * Build and format an AcceptMessage, RejectMessage or AlertMessage + * (depending on initial_state) wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +static bool +fmt_initial_message(struct client_closure *closure) +{ + bool ret = false; + debug_decl(fmt_initial_message, SUDOERS_DEBUG_UTIL); + + closure->state = closure->initial_state; + switch (closure->state) { + case SEND_ACCEPT: + /* Format and schedule AcceptMessage. */ + if ((ret = fmt_accept_message(closure, closure->log_details->evlog))) { + /* + * Move read/write events back to main sudo event loop. + * Server messages may occur at any time, so no timeout. + * Write event will be re-enabled later. + */ + closure->read_ev->setbase(closure->read_ev, NULL); + if (closure->read_ev->add(closure->read_ev, NULL) == -1) { + sudo_warn("%s", U_("unable to add event to queue")); + ret = false; + } + closure->write_ev->setbase(closure->write_ev, NULL); + } + break; + case SEND_REJECT: + /* Format and schedule RejectMessage. */ + ret = fmt_reject_message(closure, closure->log_details->evlog); + break; + case SEND_ALERT: + /* Format and schedule AlertMessage. */ + ret = fmt_alert_message(closure, closure->log_details->evlog); + break; + default: + sudo_warnx(U_("%s: unexpected state %d"), __func__, closure->state); + break; + } + debug_return_bool(ret); +} + +#ifdef notyet +/* + * Build and format a RestartMessage wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_restart_message(struct client_closure *closure) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + RestartMessage restart_msg = RESTART_MESSAGE__INIT; + TimeSpec tv = TIME_SPEC__INIT; + bool ret = false; + debug_decl(fmt_restart_message, SUDOERS_DEBUG_UTIL); + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending RestartMessage, [%lld, %ld]", __func__, + (long long)closure->restart->tv_sec, closure->restart->tv_nsec); + + tv.tv_sec = closure->restart->tv_sec; + tv.tv_nsec = closure->restart->tv_nsec; + restart_msg.resume_point = &tv; + restart_msg.log_id = closure->iolog_id; + + /* Schedule ClientMessage */ + client_msg.restart_msg = &restart_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_RESTART_MSG; + ret = fmt_client_message(closure, &client_msg); + + debug_return_bool(ret); +} +#endif + +/* + * Build and format an ExitMessage wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_exit_message(struct client_closure *closure, int exit_status, int error) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + ExitMessage exit_msg = EXIT_MESSAGE__INIT; + TimeSpec ts = TIME_SPEC__INIT; + char signame[SIG2STR_MAX]; + bool ret = false; + struct timespec run_time; + debug_decl(fmt_exit_message, SUDOERS_DEBUG_UTIL); + + if (sudo_gettime_awake(&run_time) == -1) { + sudo_warn("%s", U_("unable to get time of day")); + goto done; + } + sudo_timespecsub(&run_time, &closure->start_time, &run_time); + + ts.tv_sec = (int64_t)run_time.tv_sec; + ts.tv_nsec = (int32_t)run_time.tv_nsec; + exit_msg.run_time = &ts; + + if (error != 0) { + /* Error executing the command. */ + exit_msg.error = strerror(error); + } else { + if (WIFEXITED(exit_status)) { + exit_msg.exit_value = WEXITSTATUS(exit_status); + } else if (WIFSIGNALED(exit_status)) { + const int signo = WTERMSIG(exit_status); + if (signo <= 0 || sig2str(signo, signame) == -1) { + sudo_warnx(U_("%s: internal error, invalid signal %d"), + __func__, signo); + goto done; + } + exit_msg.signal = signame; + if (WCOREDUMP(exit_status)) + exit_msg.dumped_core = true; + exit_msg.exit_value = WTERMSIG(exit_status) | 128; + } else if (WIFSTOPPED(exit_status)) { + const int signo = WSTOPSIG(exit_status); + sudo_warnx(U_("%s: internal error, invalid signal %d"), + __func__, signo); + goto done; + } else if (WIFCONTINUED(exit_status)) { + sudo_warnx(U_("%s: internal error, invalid signal %d"), + __func__, SIGCONT); + goto done; + } else { + sudo_warnx(U_("%s: internal error, invalid exit status %d"), + __func__, exit_status); + goto done; + } + } + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending ExitMessage, exitval %d, error %s, signal %s, coredump %s", + __func__, exit_msg.exit_value, exit_msg.error ? exit_msg.error : "", + exit_msg.signal ? exit_msg.signal : "", + exit_msg.dumped_core ? "yes" : "no"); + + /* Send ClientMessage */ + client_msg.u.exit_msg = &exit_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_EXIT_MSG; + if (!fmt_client_message(closure, &client_msg)) + goto done; + + closure->state = SEND_EXIT; + ret = true; + +done: + debug_return_bool(ret); +} + +/* + * Build and format an IoBuffer wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_io_buf(struct client_closure *closure, int type, const char *buf, + unsigned int len, struct timespec *delay) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + IoBuffer iobuf_msg = IO_BUFFER__INIT; + TimeSpec ts = TIME_SPEC__INIT; + bool ret = false; + debug_decl(fmt_io_buf, SUDOERS_DEBUG_UTIL); + + /* Fill in IoBuffer. */ + ts.tv_sec = (int64_t)delay->tv_sec; + ts.tv_nsec = (int32_t)delay->tv_nsec; + iobuf_msg.delay = &ts; + iobuf_msg.data.data = (void *)buf; + iobuf_msg.data.len = len; + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending IoBuffer length %zu, type %d, size %zu", __func__, + iobuf_msg.data.len, type, io_buffer__get_packed_size(&iobuf_msg)); + + /* Schedule ClientMessage, it doesn't matter which IoBuffer we set. */ + client_msg.u.ttyout_buf = &iobuf_msg; + client_msg.type_case = type; + if (!fmt_client_message(closure, &client_msg)) + goto done; + + ret = true; + +done: + debug_return_bool(ret); +} + +/* + * Build and format a ChangeWindowSize message wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_winsize(struct client_closure *closure, unsigned int lines, + unsigned int cols, struct timespec *delay) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + ChangeWindowSize winsize_msg = CHANGE_WINDOW_SIZE__INIT; + TimeSpec ts = TIME_SPEC__INIT; + bool ret = false; + debug_decl(fmt_winsize, SUDOERS_DEBUG_UTIL); + + /* Fill in ChangeWindowSize message. */ + ts.tv_sec = (int64_t)delay->tv_sec; + ts.tv_nsec = (int32_t)delay->tv_nsec; + winsize_msg.delay = &ts; + winsize_msg.rows = (int32_t)lines; + winsize_msg.cols = (int32_t)cols; + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: sending ChangeWindowSize, %dx%d", + __func__, winsize_msg.rows, winsize_msg.cols); + + /* Send ClientMessage */ + client_msg.u.winsize_event = &winsize_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_WINSIZE_EVENT; + if (!fmt_client_message(closure, &client_msg)) + goto done; + + ret = true; + +done: + debug_return_bool(ret); +} + +/* + * Build and format a CommandSuspend message wrapped in a ClientMessage. + * Appends the wire format message to the closure's write queue. + * Returns true on success, false on failure. + */ +bool +fmt_suspend(struct client_closure *closure, const char *signame, struct timespec *delay) +{ + ClientMessage client_msg = CLIENT_MESSAGE__INIT; + CommandSuspend suspend_msg = COMMAND_SUSPEND__INIT; + TimeSpec ts = TIME_SPEC__INIT; + bool ret = false; + debug_decl(fmt_suspend, SUDOERS_DEBUG_UTIL); + + /* Fill in CommandSuspend message. */ + ts.tv_sec = (int64_t)delay->tv_sec; + ts.tv_nsec = (int32_t)delay->tv_nsec; + suspend_msg.delay = &ts; + suspend_msg.signal = (char *)signame; + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending CommandSuspend, SIG%s", __func__, suspend_msg.signal); + + /* Send ClientMessage */ + client_msg.u.suspend_event = &suspend_msg; + client_msg.type_case = CLIENT_MESSAGE__TYPE_SUSPEND_EVENT; + if (!fmt_client_message(closure, &client_msg)) + goto done; + + ret = true; + +done: + debug_return_bool(ret); +} + +/* + * Additional work to do after a ClientMessage was sent to the server. + * Advances state and formats the next ClientMessage (if any). + * XXX - better name + */ +static bool +client_message_completion(struct client_closure *closure) +{ + debug_decl(client_message_completion, SUDOERS_DEBUG_UTIL); + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: state %d", __func__, closure->state); + + switch (closure->state) { + case RECV_HELLO: + /* Waiting for ServerHello, nothing else to do. */ + break; + case SEND_ALERT: + case SEND_REJECT: + /* Nothing else to send, we are done. */ + closure->write_ev->del(closure->write_ev); + closure->read_ev->del(closure->read_ev); + closure->state = FINISHED; + break; + case SEND_ACCEPT: + case SEND_RESTART: + closure->state = SEND_IO; + break; + case SEND_IO: + /* Arbitrary number of I/O log buffers, no state change. */ + break; + case SEND_EXIT: + if (closure->log_io) { + /* Done writing, just waiting for final commit point. */ + closure->write_ev->del(closure->write_ev); + closure->state = CLOSING; + + /* Enable timeout while waiting for final commit point. */ + if (closure->read_ev->add(closure->read_ev, + &closure->log_details->server_timeout) == -1) { + sudo_warn("%s", U_("unable to add event to queue")); + debug_return_bool(false); + } + } else { + /* No commit point to wait for, we are done. */ + closure->state = FINISHED; + closure->read_ev->del(closure->read_ev); + } + break; + default: + sudo_warnx(U_("%s: unexpected state %d"), __func__, closure->state); + debug_return_bool(false); + } + debug_return_bool(true); +} + +/* + * Read the ServerHello message from the log server. + * We do this synchronously, since we don't want the command to run + * before the log server connection is completely established. + */ +bool +read_server_hello(struct client_closure *closure) +{ + struct sudo_event_base *evbase = NULL; + bool ret = false; + debug_decl(read_server_hello, SUDOERS_DEBUG_UTIL); + + /* Get new event base so we can read ServerHello synchronously. */ + evbase = sudo_ev_base_alloc(); + if (evbase == NULL) { + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + + /* Write ClientHello. */ + if (!fmt_client_hello(closure)) + goto done; + closure->write_ev->setbase(closure->write_ev, evbase); + if (closure->write_ev->add(closure->write_ev, + &closure->log_details->server_timeout) == -1) { + sudo_warnx("%s", U_("unable to add event to queue")); + goto done; + } + + /* Read ServerHello. */ + closure->read_ev->setbase(closure->read_ev, evbase); + if (closure->read_ev->add(closure->read_ev, + &closure->log_details->server_timeout) == -1) { + sudo_warnx("%s", U_("unable to add event to queue")); + goto done; + } + + /* Read/write hello messages synchronously. */ + if (sudo_ev_dispatch(evbase) == -1) { + sudo_warnx("%s", U_("error in event loop")); + goto done; + } + + if (!sudo_ev_got_break(evbase)) + ret = true; + +done: + sudo_ev_base_free(evbase); + debug_return_bool(ret); +} + +/* + * Respond to a ServerHello message from the server. + * Returns true on success, false on error. + */ +static bool +handle_server_hello(ServerHello *msg, struct client_closure *closure) +{ + size_t n; + debug_decl(handle_server_hello, SUDOERS_DEBUG_UTIL); + + if (closure->state != RECV_HELLO) { + sudo_warnx(U_("%s: unexpected state %d"), __func__, closure->state); + debug_return_bool(false); + } + + /* Check that ServerHello is valid. */ + if (msg->server_id == NULL || msg->server_id[0] == '\0') { + sudo_warnx("%s", U_("invalid ServerHello")); + debug_return_bool(false); + } + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: server ID: %s", + __func__, msg->server_id); + /* TODO: handle redirect */ + if (msg->redirect != NULL && msg->redirect[0] != '\0') { + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: redirect: %s", + __func__, msg->redirect); + } + for (n = 0; n < msg->n_servers; n++) { + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: server %zu: %s", + __func__, n + 1, msg->servers[n]); + } + + /* Does the server support logging sub-commands in a session? */ + closure->subcommands = msg->subcommands; + + debug_return_bool(true); +} + +/* + * Respond to a CommitPoint message from the server. + * Returns true on success, false on error. + */ +static bool +handle_commit_point(TimeSpec *commit_point, struct client_closure *closure) +{ + debug_decl(handle_commit_point, SUDOERS_DEBUG_UTIL); + + /* Only valid after we have sent an IO buffer. */ + if (closure->state < SEND_IO) { + sudo_warnx(U_("%s: unexpected state %d"), __func__, closure->state); + debug_return_bool(false); + } + + closure->committed.tv_sec = (time_t)commit_point->tv_sec; + closure->committed.tv_nsec = (long)commit_point->tv_nsec; + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: received [%lld, %d], elapsed [%lld, %ld], committed [%lld, %ld]", + __func__, (long long)commit_point->tv_sec, commit_point->tv_nsec, + (long long)closure->elapsed.tv_sec, closure->elapsed.tv_nsec, + (long long)closure->committed.tv_sec, closure->committed.tv_nsec); + + if (closure->state == CLOSING) { + if (sudo_timespeccmp(&closure->elapsed, &closure->committed, ==)) { + /* Last commit point received, exit event loop. */ + closure->state = FINISHED; + closure->read_ev->del(closure->read_ev); + } + } + + debug_return_bool(true); +} + +/* + * Respond to a LogId message from the server. + * Always returns true. + */ +static bool +handle_log_id(char *id, struct client_closure *closure) +{ + debug_decl(handle_log_id, SUDOERS_DEBUG_UTIL); + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: remote log ID: %s", __func__, id); + if (closure->iolog_id != NULL) { + if ((closure->iolog_id = strdup(id)) == NULL) + sudo_fatal(U_("%s: %s"), __func__, U_("unable to allocate memory")); + } + debug_return_bool(true); +} + +/* + * Respond to a ServerError message from the server. + * Always returns false. + */ +static bool +handle_server_error(char *errmsg, struct client_closure *closure) +{ + debug_decl(handle_server_error, SUDOERS_DEBUG_UTIL); + + sudo_warnx(U_("error message received from server: %s"), errmsg); + debug_return_bool(false); +} + +/* + * Respond to a ServerAbort message from the server. + * Always returns false. + */ +static bool +handle_server_abort(char *errmsg, struct client_closure *closure) +{ + debug_decl(handle_server_abort, SUDOERS_DEBUG_UTIL); + + sudo_warnx(U_("abort message received from server: %s"), errmsg); + debug_return_bool(false); +} + +/* + * Respond to a ServerMessage from the server. + * Returns true on success, false on error. + */ +static bool +handle_server_message(uint8_t *buf, size_t len, + struct client_closure *closure) +{ + ServerMessage *msg; + bool ret = false; + debug_decl(handle_server_message, SUDOERS_DEBUG_UTIL); + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: unpacking ServerMessage", __func__); + msg = server_message__unpack(NULL, len, buf); + if (msg == NULL) { + sudo_warnx(U_("unable to unpack %s size %zu"), "ServerMessage", len); + debug_return_bool(false); + } + + switch (msg->type_case) { + case SERVER_MESSAGE__TYPE_HELLO: + if (handle_server_hello(msg->u.hello, closure)) { + if ((ret = fmt_initial_message(closure))) { + if (closure->write_ev->add(closure->write_ev, + &closure->log_details->server_timeout) == -1) { + sudo_warn("%s", U_("unable to add event to queue")); + ret = false; + } + } + } + break; + case SERVER_MESSAGE__TYPE_COMMIT_POINT: + ret = handle_commit_point(msg->u.commit_point, closure); + break; + case SERVER_MESSAGE__TYPE_LOG_ID: + ret = handle_log_id(msg->u.log_id, closure); + break; + case SERVER_MESSAGE__TYPE_ERROR: + ret = handle_server_error(msg->u.error, closure); + closure->state = ERROR; + break; + case SERVER_MESSAGE__TYPE_ABORT: + ret = handle_server_abort(msg->u.abort, closure); + closure->state = ERROR; + break; + default: + sudo_warnx(U_("%s: unexpected type_case value %d"), + __func__, msg->type_case); + break; + } + + server_message__free_unpacked(msg, NULL); + debug_return_bool(ret); +} + +/* + * Expand buf as needed or just reset it. + * XXX - share with logsrvd/sendlog + */ +static bool +expand_buf(struct connection_buffer *buf, size_t needed) +{ + void *newdata; + debug_decl(expand_buf, SUDOERS_DEBUG_UTIL); + + if (buf->size < needed) { + /* Expand buffer. */ + const size_t newsize = sudo_pow2_roundup(needed); + if (newsize < needed) { + /* overflow */ + errno = ENOMEM; + goto oom; + } + if ((newdata = malloc(needed)) == NULL) + goto oom; + if (buf->off > 0) + memcpy(newdata, buf->data + buf->off, buf->len - buf->off); + free(buf->data); + buf->data = newdata; + buf->size = newsize; + } else { + /* Just reset existing buffer. */ + if (buf->off > 0) { + memmove(buf->data, buf->data + buf->off, + buf->len - buf->off); + } + } + buf->len -= buf->off; + buf->off = 0; + + debug_return_bool(true); +oom: + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + debug_return_bool(false); +} + +/* + * Read and unpack a ServerMessage (read callback). + */ +static void +server_msg_cb(int fd, int what, void *v) +{ + struct client_closure *closure = v; + struct connection_buffer *buf = &closure->read_buf; + size_t nread; + uint32_t msg_len; + debug_decl(server_msg_cb, SUDOERS_DEBUG_UTIL); + + /* For TLS we may need to read as part of SSL_write_ex(). */ + if (closure->write_instead_of_read) { + closure->write_instead_of_read = false; + client_msg_cb(fd, what, v); + debug_return; + } + + if (what == SUDO_PLUGIN_EV_TIMEOUT) { + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: timed out reading from server", + __func__); + goto bad; + } + + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: reading ServerMessage", __func__); +#if defined(HAVE_OPENSSL) + if (closure->ssl != NULL) { + const int result = SSL_read_ex(closure->ssl, buf->data + buf->len, + buf->size - buf->len, &nread); + if (result <= 0) { + unsigned long errcode; + const char *errstr; + + switch (SSL_get_error(closure->ssl, result)) { + case SSL_ERROR_ZERO_RETURN: + /* TLS connection shutdown cleanly */ + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "TLS connection shut down cleanly"); + nread = 0; + break; + case SSL_ERROR_WANT_READ: + /* ssl wants to read more, read event is always active */ + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "SSL_read_ex returns SSL_ERROR_WANT_READ"); + debug_return; + case SSL_ERROR_WANT_WRITE: + /* ssl wants to write, so schedule the write handler */ + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "SSL_read_ex returns SSL_ERROR_WANT_WRITE"); + if (!closure->write_ev->pending(closure->write_ev, + SUDO_PLUGIN_EV_WRITE, NULL)) { + /* Enable a temporary write event. */ + if (closure->write_ev->add(closure->write_ev, NULL) == -1) { + sudo_warn("%s", U_("unable to add event to queue")); + goto bad; + } + closure->temporary_write_event = true; + } + /* Redirect write event to finish SSL_read_ex() */ + closure->read_instead_of_write = true; + debug_return; + case SSL_ERROR_SSL: + /* + * For TLS 1.3, if the cert verify function on the server + * returns an error, OpenSSL will send an internal error + * alert when we read ServerHello. Convert to a more useful + * message and hope that no actual internal error occurs. + */ + errcode = ERR_get_error(); +#if !defined(HAVE_WOLFSSL) + if (closure->state == RECV_HELLO && + ERR_GET_REASON(errcode) == SSL_R_TLSV1_ALERT_INTERNAL_ERROR) { + errstr = U_("host name does not match certificate"); + } else +#endif + { + errstr = ERR_reason_error_string(errcode); + } + sudo_warnx("%s", errstr ? errstr : strerror(errno)); + goto bad; + case SSL_ERROR_SYSCALL: + if (nread == 0) + sudo_warnx("%s", U_("lost connection to log server")); + else + sudo_warn("SSL_read_ex"); + goto bad; + default: + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx("SSL_read_ex: %s", + errstr ? errstr : strerror(errno)); + goto bad; + } + } + } else +#endif /* HAVE_OPENSSL */ + { + nread = (size_t)read(fd, buf->data + buf->len, buf->size - buf->len); + } + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: received %zd bytes from server", + __func__, nread); + switch (nread) { + case (size_t)-1: + if (errno == EAGAIN) + debug_return; + sudo_warn("read"); + goto bad; + case 0: + sudo_warnx("%s", U_("lost connection to log server")); + goto bad; + default: + break; + } + buf->len += nread; + + while (buf->len - buf->off >= sizeof(msg_len)) { + /* Read wire message size (uint32_t in network byte order). */ + memcpy(&msg_len, buf->data + buf->off, sizeof(msg_len)); + msg_len = ntohl(msg_len); + + if (msg_len > MESSAGE_SIZE_MAX) { + sudo_warnx(U_("server message too large: %u"), msg_len); + goto bad; + } + + if (msg_len + sizeof(msg_len) > buf->len - buf->off) { + /* Incomplete message, we'll read the rest next time. */ + if (!expand_buf(buf, msg_len + sizeof(msg_len))) + goto bad; + debug_return; + } + + /* Parse ServerMessage, could be zero bytes. */ + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: parsing ServerMessage, size %u", __func__, msg_len); + buf->off += sizeof(msg_len); + if (!handle_server_message(buf->data + buf->off, msg_len, closure)) + goto bad; + buf->off += msg_len; + } + buf->len -= buf->off; + buf->off = 0; + debug_return; +bad: + if (closure->log_details->ignore_log_errors) { + /* Disable plugin, the command continues. */ + closure->disabled = true; + closure->read_ev->del(closure->read_ev); + } else { + /* Break out of sudo event loop and kill the command. */ + closure->read_ev->loopbreak(closure->read_ev); + } + debug_return; +} + +/* + * Send a ClientMessage to the server (write callback). + */ +static void +client_msg_cb(int fd, int what, void *v) +{ + struct client_closure *closure = v; + struct connection_buffer *buf; + size_t nwritten; + debug_decl(client_msg_cb, SUDOERS_DEBUG_UTIL); + + /* For TLS we may need to write as part of SSL_read_ex(). */ + if (closure->read_instead_of_write) { + closure->read_instead_of_write = false; + /* Delete write event if it was only due to SSL_read_ex(). */ + if (closure->temporary_write_event) { + closure->temporary_write_event = false; + closure->write_ev->del(closure->write_ev); + } + server_msg_cb(fd, what, v); + debug_return; + } + + if (what == SUDO_PLUGIN_EV_TIMEOUT) { + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: timed out writing to server", + __func__); + goto bad; + } + + if ((buf = TAILQ_FIRST(&closure->write_bufs)) == NULL) { + sudo_warnx("%s", U_("missing write buffer")); + goto bad; + } + + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: sending %zu bytes to server", __func__, buf->len - buf->off); + +#if defined(HAVE_OPENSSL) + if (closure->ssl != NULL) { + const int result = SSL_write_ex(closure->ssl, buf->data + buf->off, + buf->len - buf->off, &nwritten); + if (result <= 0) { + const char *errstr; + + switch (SSL_get_error(closure->ssl, result)) { + case SSL_ERROR_ZERO_RETURN: + /* TLS connection shutdown cleanly */ + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "TLS connection shut down cleanly"); + goto bad; + case SSL_ERROR_WANT_READ: + /* ssl wants to read, read event always active */ + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "SSL_write_ex returns SSL_ERROR_WANT_READ"); + /* Redirect read event to finish SSL_write_ex() */ + closure->write_instead_of_read = true; + debug_return; + case SSL_ERROR_WANT_WRITE: + /* ssl wants to write more, write event remains active */ + sudo_debug_printf(SUDO_DEBUG_NOTICE|SUDO_DEBUG_LINENO, + "SSL_write_ex returns SSL_ERROR_WANT_WRITE"); + debug_return; + case SSL_ERROR_SSL: + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx("%s", errstr ? errstr : strerror(errno)); + goto bad; + case SSL_ERROR_SYSCALL: + sudo_warn("SSL_write_ex"); + goto bad; + default: + errstr = ERR_reason_error_string(ERR_get_error()); + sudo_warnx("SSL_write_ex: %s", + errstr ? errstr : strerror(errno)); + goto bad; + } + } + } else +#endif /* HAVE_OPENSSL */ + { + nwritten = (size_t)write(fd, buf->data + buf->off, buf->len - buf->off); + } + + if (nwritten == (size_t)-1) { + sudo_warn("send"); + goto bad; + } + buf->off += nwritten; + + if (buf->off == buf->len) { + /* sent entire message, move buf to free list */ + sudo_debug_printf(SUDO_DEBUG_INFO, + "%s: finished sending %zu bytes to server", __func__, buf->len); + buf->off = 0; + buf->len = 0; + TAILQ_REMOVE(&closure->write_bufs, buf, entries); + TAILQ_INSERT_TAIL(&closure->free_bufs, buf, entries); + if (TAILQ_EMPTY(&closure->write_bufs)) { + /* Write queue empty, check for state change. */ + closure->write_ev->del(closure->write_ev); + if (!client_message_completion(closure)) + goto bad; + } + } + debug_return; + +bad: + if (closure->log_details->ignore_log_errors) { + /* Disable plugin, the command continues. */ + closure->disabled = true; + closure->write_ev->del(closure->read_ev); + closure->write_ev->del(closure->write_ev); + } else { + /* Break out of sudo event loop and kill the command. */ + closure->write_ev->loopbreak(closure->write_ev); + } + debug_return; +} + +/* + * Allocate and initialize a new client closure + */ +static struct client_closure * +client_closure_alloc(struct log_details *details, struct timespec *now, + bool log_io, enum client_state initial_state, const char *reason) +{ + struct client_closure *closure; + debug_decl(client_closure_alloc, SUDOERS_DEBUG_UTIL); + + if (plugin_event_alloc == NULL) { + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "plugin_event_alloc is not set"); + debug_return_ptr(NULL); + } + + if ((closure = calloc(1, sizeof(*closure))) == NULL) + goto oom; + + closure->sock = -1; + closure->log_io = log_io; + closure->reason = reason; + closure->state = RECV_HELLO; + closure->initial_state = initial_state; + + closure->start_time.tv_sec = now->tv_sec; + closure->start_time.tv_nsec = now->tv_nsec; + + TAILQ_INIT(&closure->write_bufs); + TAILQ_INIT(&closure->free_bufs); + + closure->read_buf.size = 64 * 1024; + closure->read_buf.data = malloc(closure->read_buf.size); + if (closure->read_buf.data == NULL) + goto oom; + + if ((closure->read_ev = plugin_event_alloc()) == NULL) + goto oom; + + if ((closure->write_ev = plugin_event_alloc()) == NULL) + goto oom; + + closure->log_details = details; + + debug_return_ptr(closure); +oom: + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + client_closure_free(closure); + debug_return_ptr(NULL); +} + +struct client_closure * +log_server_open(struct log_details *details, struct timespec *now, + bool log_io, enum client_state initial_state, const char *reason) +{ + struct client_closure *closure; + static bool warned = false; + debug_decl(log_server_open, SUDOERS_DEBUG_UTIL); + + closure = client_closure_alloc(details, now, log_io, initial_state, + reason); + if (closure == NULL) + goto bad; + + /* Connect to log first available log server. */ + if (!log_server_connect(closure)) { + /* TODO: support offline logs if server unreachable */ + if (!warned) { + sudo_warnx("%s", U_("unable to connect to log server")); + warned = true; + } + goto bad; + } + + /* Read ServerHello synchronously or fail. */ + if (read_server_hello(closure)) + debug_return_ptr(closure); + +bad: + client_closure_free(closure); + debug_return_ptr(NULL); +} + +/* + * Send ExitMessage, wait for final commit message and free closure. + */ +bool +log_server_close(struct client_closure *closure, int exit_status, int error) +{ + struct sudo_event_base *evbase = NULL; + bool ret = false; + debug_decl(log_server_close, SUDOERS_DEBUG_UTIL); + + if (closure->disabled) + goto done; + + /* Format and append an ExitMessage to the write queue. */ + if (!fmt_exit_message(closure, exit_status, error)) + goto done; + + /* + * Create private event base and reparent the read/write events. + * We cannot use the main sudo event loop as it has already exited. + */ + if ((evbase = sudo_ev_base_alloc()) == NULL) { + sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory")); + goto done; + } + + /* Enable read event to receive server messages. */ + closure->read_ev->setbase(closure->read_ev, evbase); + if (closure->read_ev->add(closure->read_ev, + &closure->log_details->server_timeout) == -1) { + sudo_warn("%s", U_("unable to add event to queue")); + goto done; + } + + /* Enable the write event to write the ExitMessage. */ + closure->write_ev->setbase(closure->write_ev, evbase); + if (closure->write_ev->add(closure->write_ev, + &closure->log_details->server_timeout) == -1) { + sudo_warn("%s", U_("unable to add event to queue")); + goto done; + } + + /* Loop until queues are flushed and final commit point received. */ + sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO, + "flushing buffers and waiting for final commit point"); + if (sudo_ev_dispatch(evbase) == -1 || sudo_ev_got_break(evbase)) { + sudo_warnx("%s", U_("error in event loop")); + goto done; + } + + ret = true; + +done: + sudo_ev_base_free(evbase); + client_closure_free(closure); + debug_return_bool(ret); +} + +#endif /* SUDOERS_LOG_CLIENT */ |