mirrors
/
sudo
mirror of https://github.com/sudo-project/sudo.git
0
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
sudo/plugins/sudoers/log_client.c

2114 lines
62 KiB
C
Raw Permalink Blame History

/*
* 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);
current_cert = X509_STORE_CTX_get_current_cert(ctx);
/* if pre-verification of the cert failed, just propagate that result back */
if (preverify_ok != 1) {
int err = X509_STORE_CTX_get_error(ctx);
char current_cert_name[256] = "";
if (current_cert != NULL)
X509_NAME_oneline(X509_get_subject_name(current_cert), current_cert_name, sizeof(current_cert_name));
sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
"TLS verification failed for cert '%s': '%d:%s'", current_cert_name,
err, X509_verify_cert_error_string(err));
debug_return_int(0);
}
/* since this callback is called for each cert in the chain,
* check that current cert is the peer's certificate
*/
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.
*/
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 *start_time,
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;
if (start_time != NULL) {
closure->start_time.tv_sec = start_time->tv_sec;
closure->start_time.tv_nsec = start_time->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 *start_time,
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, start_time, 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 */
Reference in New Issue View Git Blame Copy Permalink