Adding upstream version 1.9.13p3.upstream/1.9.13p3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1367 insertions, 0 deletions

diff --git a/plugins/sudoers/iolog.c b/plugins/sudoers/iolog.c
new file mode 100644
index 0000000..ec93698
--- /dev/null
+++ b/plugins/sudoers/iolog.c
@@ -0,0 +1,1367 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 2009-2022 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>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <pwd.h>
+#include <grp.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+
+#include "sudoers.h"
+#include "sudo_eventlog.h"
+#include "sudo_iolog.h"
+#include "strlist.h"
+#ifdef SUDOERS_LOG_CLIENT
+# include "log_client.h"
+#endif
+
+static struct iolog_file iolog_files[] = {
+    { false },	/* IOFD_STDIN */
+    { false },	/* IOFD_STDOUT */
+    { false },	/* IOFD_STDERR */
+    { false },	/* IOFD_TTYIN  */
+    { false },	/* IOFD_TTYOUT */
+    { true, },	/* IOFD_TIMING */
+};
+
+static struct sudoers_io_operations {
+    int (*open)(struct timespec *now);
+    void (*close)(int exit_status, int error, const char **errstr);
+    int (*log)(int event, const char *buf, unsigned int len,
+	struct timespec *delay, const char **errstr);
+    int (*change_winsize)(unsigned int lines, unsigned int cols,
+	struct timespec *delay, const char **errstr);
+    int (*suspend)(const char *signame, struct timespec *delay,
+	const char **errstr);
+} io_operations;
+
+static struct log_details iolog_details;
+static bool warned = false;
+static bool log_passwords = true;
+static int iolog_dir_fd = -1;
+static struct timespec last_time;
+static void *passprompt_regex_handle;
+static void sudoers_io_setops(void);
+
+/* sudoers_io is declared at the end of this file. */
+extern sudo_dso_public struct io_plugin sudoers_io;
+
+/*
+ * Sudoers callback for maxseq Defaults setting.
+ */
+bool
+cb_maxseq(const char *file, int line, int column,
+    const union sudo_defs_val *sd_un, int op)
+{
+    const char *errstr;
+    unsigned int value;
+    debug_decl(cb_maxseq, SUDOERS_DEBUG_UTIL);
+
+    value = sudo_strtonum(sd_un->str, 0, SESSID_MAX, &errstr);
+    if (errstr != NULL) {
+        if (errno != ERANGE) {
+            sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
+                "bad maxseq: %s: %s", sd_un->str, errstr);
+            debug_return_bool(false);
+        }
+        /* Out of range, clamp to SESSID_MAX as documented. */
+        value = SESSID_MAX;
+    }
+    iolog_set_maxseq(value);
+    debug_return_bool(true);
+}
+
+/*
+ * Sudoers callback for iolog_user Defaults setting.
+ */
+bool
+cb_iolog_user(const char *file, int line, int column,
+    const union sudo_defs_val *sd_un, int op)
+{
+    const char *name = sd_un->str;
+    struct passwd *pw;
+    debug_decl(cb_iolog_user, SUDOERS_DEBUG_UTIL);
+
+    /* NULL name means reset to default. */
+    if (name == NULL) {
+	iolog_set_owner(ROOT_UID, ROOT_GID);
+    } else {
+	if ((pw = sudo_getpwnam(name)) == NULL) {
+	    log_warningx(SLOG_SEND_MAIL, N_("unknown user %s"), name);
+	    debug_return_bool(false);
+	}
+	iolog_set_owner(pw->pw_uid, pw->pw_gid);
+	sudo_pw_delref(pw);
+    }
+
+    debug_return_bool(true);
+}
+
+/*
+ * Look up I/O log group-ID from group name.
+ */
+bool
+cb_iolog_group(const char *file, int line, int column,
+    const union sudo_defs_val *sd_un, int op)
+{
+    const char *name = sd_un->str;
+    struct group *gr;
+    debug_decl(cb_iolog_group, SUDOERS_DEBUG_UTIL);
+
+    /* NULL name means reset to default. */
+    if (name == NULL) {
+	iolog_set_gid(ROOT_GID);
+    } else {
+	if ((gr = sudo_getgrnam(name)) == NULL) {
+	    log_warningx(SLOG_SEND_MAIL, N_("unknown group %s"), name);
+	    debug_return_bool(false);
+	}
+	iolog_set_gid(gr->gr_gid);
+	sudo_gr_delref(gr);
+    }
+
+    debug_return_bool(true);
+}
+
+/*
+ * Sudoers callback for iolog_mode Defaults setting.
+ */
+bool
+cb_iolog_mode(const char *file, int line, int column,
+    const union sudo_defs_val *sd_un, int op)
+{
+    iolog_set_mode(sd_un->mode);
+    return true;
+}
+
+/*
+ * Make a shallow copy of a NULL-terminated argument or environment vector.
+ * Only the outer array is allocated, the pointers inside are copied.
+ * The caller is responsible for freeing the returned copy.
+ */
+static char **
+copy_vector_shallow(char * const *vec)
+{
+    char **copy;
+    size_t len;
+    debug_decl(copy_vector, SUDOERS_DEBUG_UTIL);
+
+    for (len = 0; vec[len] != NULL; len++)
+	continue;
+
+    if ((copy = reallocarray(NULL, len + 1, sizeof(char *))) != NULL) {
+	for (len = 0; vec[len] != NULL; len++)
+	    copy[len] = vec[len];
+	copy[len] = NULL;
+    }
+
+    debug_return_ptr(copy);
+}
+
+static void
+free_iolog_details(void)
+{
+    debug_decl(free_iolog_details, SUDOERS_DEBUG_PLUGIN);
+
+    if (iolog_details.evlog != NULL) {
+	/* We only make a shallow copy of argv and envp. */
+	free(iolog_details.evlog->argv);
+	iolog_details.evlog->argv = NULL;
+	free(iolog_details.evlog->envp);
+	iolog_details.evlog->envp = NULL;
+	eventlog_free(iolog_details.evlog);
+    }
+    str_list_free(iolog_details.log_servers);
+#if defined(HAVE_OPENSSL)
+    free(iolog_details.ca_bundle);
+    free(iolog_details.cert_file);
+    free(iolog_details.key_file);
+#endif /* HAVE_OPENSSL */
+
+    debug_return;
+}
+
+/*
+ * Convert a comma-separated list to a string list.
+ */
+static struct sudoers_str_list *
+deserialize_stringlist(const char *s)
+{
+    struct sudoers_str_list *strlist;
+    struct sudoers_string *str;
+    const char *s_end = s + strlen(s);
+    const char *cp, *ep;
+    debug_decl(deserialize_stringlist, SUDOERS_DEBUG_UTIL);
+
+    if ((strlist = str_list_alloc()) == NULL)
+	debug_return_ptr(NULL);
+
+    for (cp = sudo_strsplit(s, s_end, ",", &ep); cp != NULL;
+	    cp = sudo_strsplit(NULL, s_end, ",", &ep)) {
+	if (cp == ep)
+	    continue;
+	if ((str = malloc(sizeof(*str))) == NULL)
+	    goto bad;
+	if ((str->str = strndup(cp, (ep - cp))) == NULL) {
+	    free(str);
+	    goto bad;
+	}
+	unescape_string(str->str);
+	STAILQ_INSERT_TAIL(strlist, str, entries);
+    }
+    if (STAILQ_EMPTY(strlist))
+	goto bad;
+
+    debug_return_ptr(strlist);
+
+bad:
+    str_list_free(strlist);
+    debug_return_ptr(NULL);
+}
+
+/*
+ * Set passprompt regex filter based on a comma-separated string.
+ * Returns a passprompt regex handle pointer.
+ */
+static void *
+set_passprompt_regex(const char *cstr)
+{
+    void *handle;
+    char *cp, *str, *last = NULL;
+    debug_decl(set_passprompt_regex, SUDOERS_DEBUG_UTIL);
+
+    handle = iolog_pwfilt_alloc();
+    str = strdup(cstr);
+    if (handle == NULL || str == NULL) {
+	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	goto bad;
+    }
+
+    for ((cp = strtok_r(str, ",", &last)); cp != NULL;
+	    (cp = strtok_r(NULL, ",", &last))) {
+	unescape_string(cp);
+	if (!iolog_pwfilt_add(handle, cp))
+	    goto bad;
+    }
+
+    free(str);
+    debug_return_ptr(handle);
+bad:
+    free(str);
+    iolog_pwfilt_free(handle);
+    debug_return_ptr(NULL);
+}
+
+/*
+ * Pull out I/O log related data from user_info and command_info arrays.
+ * Returns true if I/O logging is enabled, false if not and -1 on error.
+ */
+static int
+iolog_deserialize_info(struct log_details *details, char * const user_info[],
+    char * const command_info[], char * const argv[], char * const user_env[])
+{
+    struct eventlog *evlog;
+    const char *runas_uid_str = "0", *runas_euid_str = NULL;
+    const char *runas_gid_str = "0", *runas_egid_str = NULL;
+    const char *errstr;
+    char idbuf[MAX_UID_T_LEN + 2];
+    char * const *cur;
+    struct passwd *pw;
+    struct group *gr;
+    id_t id;
+    debug_decl(iolog_deserialize_info, SUDOERS_DEBUG_UTIL);
+
+    if ((evlog = calloc(1, sizeof(*evlog))) == NULL)
+	goto oom;
+    details->evlog = evlog;
+
+    evlog->lines = 24;
+    evlog->columns = 80;
+    evlog->runuid = ROOT_UID;
+    evlog->rungid = 0;
+    sudo_gettime_real(&evlog->submit_time);
+
+    for (cur = user_info; *cur != NULL; cur++) {
+	switch (**cur) {
+	case 'c':
+	    if (strncmp(*cur, "cols=", sizeof("cols=") - 1) == 0) {
+		int n = sudo_strtonum(*cur + sizeof("cols=") - 1, 1, INT_MAX,
+		    NULL);
+		if (n > 0)
+		    evlog->columns = n;
+		continue;
+	    }
+	    if (strncmp(*cur, "cwd=", sizeof("cwd=") - 1) == 0) {
+		free(evlog->cwd);
+		evlog->cwd = strdup(*cur + sizeof("cwd=") - 1);
+		if (evlog->cwd == NULL)
+		    goto oom;
+		continue;
+	    }
+	    break;
+	case 'h':
+	    if (strncmp(*cur, "host=", sizeof("host=") - 1) == 0) {
+		free(evlog->submithost);
+		evlog->submithost = strdup(*cur + sizeof("host=") - 1);
+		if (evlog->submithost == NULL)
+		    goto oom;
+		continue;
+	    }
+	    break;
+	case 'l':
+	    if (strncmp(*cur, "lines=", sizeof("lines=") - 1) == 0) {
+		int n = sudo_strtonum(*cur + sizeof("lines=") - 1, 1, INT_MAX,
+		    NULL);
+		if (n > 0)
+		    evlog->lines = n;
+		continue;
+	    }
+	    break;
+	case 't':
+	    if (strncmp(*cur, "tty=", sizeof("tty=") - 1) == 0) {
+		free(evlog->ttyname);
+		evlog->ttyname = strdup(*cur + sizeof("tty=") - 1);
+		if (evlog->ttyname == NULL)
+		    goto oom;
+		continue;
+	    }
+	    break;
+	case 'u':
+	    if (strncmp(*cur, "user=", sizeof("user=") - 1) == 0) {
+		free(evlog->submituser);
+		evlog->submituser = strdup(*cur + sizeof("user=") - 1);
+		if (evlog->submituser == NULL)
+		    goto oom;
+		continue;
+	    }
+	    break;
+	}
+    }
+
+    for (cur = command_info; *cur != NULL; cur++) {
+	switch (**cur) {
+	case 'c':
+	    if (strncmp(*cur, "command=", sizeof("command=") - 1) == 0) {
+		free(evlog->command);
+		evlog->command = strdup(*cur + sizeof("command=") - 1);
+		if (evlog->command == NULL)
+		    goto oom;
+		continue;
+	    }
+	    if (strncmp(*cur, "chroot=", sizeof("chroot=") - 1) == 0) {
+		free(evlog->runchroot);
+		evlog->runchroot = strdup(*cur + sizeof("chroot=") - 1);
+		if (evlog->runchroot == NULL)
+		    goto oom;
+		continue;
+	    }
+	    break;
+	case 'i':
+	    if (strncmp(*cur, "ignore_iolog_errors=", sizeof("ignore_iolog_errors=") - 1) == 0) {
+		if (sudo_strtobool(*cur + sizeof("ignore_iolog_errors=") - 1) == true)
+		    details->ignore_log_errors = true;
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_path=", sizeof("iolog_path=") - 1) == 0) {
+		free(evlog->iolog_path);
+		evlog->iolog_path = strdup(*cur + sizeof("iolog_path=") - 1);
+		if (evlog->iolog_path == NULL)
+		    goto oom;
+		evlog->iolog_file = sudo_basename(evlog->iolog_path);
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_stdin=", sizeof("iolog_stdin=") - 1) == 0) {
+		if (sudo_strtobool(*cur + sizeof("iolog_stdin=") - 1) == true)
+		    iolog_files[IOFD_STDIN].enabled = true;
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_stdout=", sizeof("iolog_stdout=") - 1) == 0) {
+		if (sudo_strtobool(*cur + sizeof("iolog_stdout=") - 1) == true)
+		    iolog_files[IOFD_STDOUT].enabled = true;
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_stderr=", sizeof("iolog_stderr=") - 1) == 0) {
+		if (sudo_strtobool(*cur + sizeof("iolog_stderr=") - 1) == true)
+		    iolog_files[IOFD_STDERR].enabled = true;
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_ttyin=", sizeof("iolog_ttyin=") - 1) == 0) {
+		if (sudo_strtobool(*cur + sizeof("iolog_ttyin=") - 1) == true)
+		    iolog_files[IOFD_TTYIN].enabled = true;
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_ttyout=", sizeof("iolog_ttyout=") - 1) == 0) {
+		if (sudo_strtobool(*cur + sizeof("iolog_ttyout=") - 1) == true)
+		    iolog_files[IOFD_TTYOUT].enabled = true;
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_compress=", sizeof("iolog_compress=") - 1) == 0) {
+		int val = sudo_strtobool(*cur + sizeof("iolog_compress=") - 1);
+		if (val != -1) {
+		    iolog_set_compress(val);
+		} else {
+		    sudo_debug_printf(SUDO_DEBUG_WARN,
+			"%s: unable to parse %s", __func__, *cur);
+		}
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_flush=", sizeof("iolog_flush=") - 1) == 0) {
+		int val = sudo_strtobool(*cur + sizeof("iolog_flush=") - 1);
+		if (val != -1) {
+		    iolog_set_flush(val);
+		} else {
+		    sudo_debug_printf(SUDO_DEBUG_WARN,
+			"%s: unable to parse %s", __func__, *cur);
+		}
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_mode=", sizeof("iolog_mode=") - 1) == 0) {
+		mode_t mode = sudo_strtomode(*cur + sizeof("iolog_mode=") - 1, &errstr);
+		if (errstr == NULL) {
+		    iolog_set_mode(mode);
+		} else {
+		    sudo_debug_printf(SUDO_DEBUG_WARN,
+			"%s: unable to parse %s", __func__, *cur);
+		}
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_group=", sizeof("iolog_group=") - 1) == 0) {
+		gr = sudo_getgrnam(*cur + sizeof("iolog_group=") - 1);
+		if (gr == NULL) {
+		    sudo_debug_printf(SUDO_DEBUG_WARN, "%s: unknown group %s",
+			__func__, *cur + sizeof("iolog_group=") - 1);
+		} else {
+		    iolog_set_gid(gr->gr_gid);
+		    sudo_gr_delref(gr);
+		}
+		continue;
+	    }
+	    if (strncmp(*cur, "iolog_user=", sizeof("iolog_user=") - 1) == 0) {
+		pw = sudo_getpwnam(*cur + sizeof("iolog_user=") - 1);
+		if (pw == NULL) {
+		    sudo_debug_printf(SUDO_DEBUG_WARN, "%s: unknown user %s",
+			__func__, *cur + sizeof("iolog_user=") - 1);
+		} else {
+		    iolog_set_owner(pw->pw_uid, pw->pw_gid);
+		    sudo_pw_delref(pw);
+		}
+		continue;
+	    }
+	    break;
+	case 'l':
+	    if (strncmp(*cur, "log_passwords=", sizeof("log_passwords=") - 1) == 0) {
+		int val = sudo_strtobool(*cur + sizeof("log_passwords=") - 1);
+		if (val != -1) {
+		    log_passwords = val;
+		} else {
+		    sudo_debug_printf(SUDO_DEBUG_WARN,
+			"%s: unable to parse %s", __func__, *cur);
+		}
+		continue;
+	    }
+	    if (strncmp(*cur, "log_servers=", sizeof("log_servers=") - 1) == 0) {
+		details->log_servers =
+		    deserialize_stringlist(*cur + sizeof("log_servers=") - 1);
+		if (!details->log_servers)
+		    goto oom;
+		continue;
+	    }
+	    if (strncmp(*cur, "log_server_timeout=", sizeof("log_server_timeout=") - 1) == 0) {
+		details->server_timeout.tv_sec =
+		    sudo_strtonum(*cur + sizeof("log_server_timeout=") - 1, 1,
+		    TIME_T_MAX, NULL);
+		continue;
+	    }
+            if (strncmp(*cur, "log_server_keepalive=", sizeof("log_server_keepalive=") - 1) == 0) {
+                int val = sudo_strtobool(*cur + sizeof("log_server_keepalive=") - 1);
+                if (val != -1) {
+                    details->keepalive = val;
+                } else {
+                    sudo_debug_printf(SUDO_DEBUG_WARN,
+                        "%s: unable to parse %s", __func__, *cur);
+                }
+                continue;
+            }
+#if defined(HAVE_OPENSSL)
+            if (strncmp(*cur, "log_server_cabundle=", sizeof("log_server_cabundle=") - 1) == 0) {
+		free(details->ca_bundle);
+                details->ca_bundle = strdup(*cur + sizeof("log_server_cabundle=") - 1);
+		if (details->ca_bundle == NULL)
+		    goto oom;
+                continue;
+            }
+            if (strncmp(*cur, "log_server_peer_cert=", sizeof("log_server_peer_cert=") - 1) == 0) {
+		free(details->cert_file);
+                details->cert_file = strdup(*cur + sizeof("log_server_peer_cert=") - 1);
+		if (details->cert_file == NULL)
+		    goto oom;
+                continue;
+            }
+            if (strncmp(*cur, "log_server_peer_key=", sizeof("log_server_peer_key=") - 1) == 0) {
+		free(details->key_file);
+                details->key_file = strdup(*cur + sizeof("log_server_peer_key=") - 1);
+		if (details->key_file == NULL)
+		    goto oom;
+                continue;
+            }
+            if (strncmp(*cur, "log_server_verify=", sizeof("log_server_verify=") - 1) == 0) {
+                int val = sudo_strtobool(*cur + sizeof("log_server_verify=") - 1);
+                if (val != -1) {
+                    details->verify_server = val;
+                } else {
+                    sudo_debug_printf(SUDO_DEBUG_WARN,
+                        "%s: unable to parse %s", __func__, *cur);
+                }
+                continue;
+            }
+#endif /* HAVE_OPENSSL */
+	    break;
+	case 'm':
+	    if (strncmp(*cur, "maxseq=", sizeof("maxseq=") - 1) == 0) {
+		union sudo_defs_val sd_un;
+		sd_un.str = *cur + sizeof("maxseq=") - 1;
+		cb_maxseq("policy", -1, -1, &sd_un, true);
+		continue;
+	    }
+	    break;
+	case 'p':
+	    if (strncmp(*cur, "passprompt_regex=", sizeof("passprompt_regex=") - 1) == 0) {
+		iolog_pwfilt_free(passprompt_regex_handle);
+		passprompt_regex_handle =
+		    set_passprompt_regex(*cur + sizeof("passprompt_regex=") - 1);
+		if (passprompt_regex_handle == NULL)
+		    debug_return_int(-1);
+	    }
+	    break;
+	case 'r':
+	    if (strncmp(*cur, "runas_gid=", sizeof("runas_gid=") - 1) == 0) {
+		runas_gid_str = *cur + sizeof("runas_gid=") - 1;
+		continue;
+	    }
+	    if (strncmp(*cur, "runas_egid=", sizeof("runas_egid=") - 1) == 0) {
+		runas_egid_str = *cur + sizeof("runas_egid=") - 1;
+		continue;
+	    }
+	    if (strncmp(*cur, "runas_uid=", sizeof("runas_uid=") - 1) == 0) {
+		runas_uid_str = *cur + sizeof("runas_uid=") - 1;
+		continue;
+	    }
+	    if (strncmp(*cur, "runas_euid=", sizeof("runas_euid=") - 1) == 0) {
+		runas_euid_str = *cur + sizeof("runas_euid=") - 1;
+		continue;
+	    }
+	    if (strncmp(*cur, "runcwd=", sizeof("runcwd=") - 1) == 0) {
+		free(evlog->runcwd);
+		evlog->runcwd = strdup(*cur + sizeof("runcwd=") - 1);
+		if (evlog->runcwd == NULL)
+		    goto oom;
+		continue;
+	    }
+	    break;
+	}
+    }
+
+    if (argv != NULL) {
+	evlog->argv = copy_vector_shallow(argv);
+	if (evlog->argv == NULL)
+	    goto oom;
+    }
+    if (user_env != NULL) {
+	evlog->envp = copy_vector_shallow(user_env);
+	if (evlog->envp ==  NULL)
+	    goto oom;
+    }
+
+    /*
+     * Lookup runas user and group, preferring effective over real uid/gid.
+     */
+    if (runas_euid_str != NULL)
+	runas_uid_str = runas_euid_str;
+    if (runas_uid_str != NULL) {
+	id = sudo_strtoid(runas_uid_str, &errstr);
+	if (errstr != NULL)
+	    sudo_warnx("runas uid %s: %s", runas_uid_str, U_(errstr));
+	else
+	    evlog->runuid = (uid_t)id;
+    }
+    if (runas_egid_str != NULL)
+	runas_gid_str = runas_egid_str;
+    if (runas_gid_str != NULL) {
+	id = sudo_strtoid(runas_gid_str, &errstr);
+	if (errstr != NULL)
+	    sudo_warnx("runas gid %s: %s", runas_gid_str, U_(errstr));
+	else
+	    evlog->rungid = (gid_t)id;
+    }
+
+    pw = sudo_getpwuid(evlog->runuid);
+    if (pw != NULL) {
+	gid_t pw_gid = pw->pw_gid;
+	free(evlog->runuser);
+	evlog->runuser = strdup(pw->pw_name);
+	sudo_pw_delref(pw);
+	if (evlog->runuser == NULL)
+	    goto oom;
+	if (evlog->rungid != pw_gid) {
+	    gr = sudo_getgrgid(evlog->rungid);
+	    if (gr != NULL) {
+		free(evlog->rungroup);
+		evlog->rungroup = strdup(gr->gr_name);
+		sudo_gr_delref(gr);
+		if (evlog->rungroup == NULL)
+		    goto oom;
+	    } else {
+		idbuf[0] = '#';
+		strlcpy(&idbuf[1], runas_gid_str, sizeof(idbuf) - 1);
+		free(evlog->rungroup);
+		evlog->rungroup = strdup(idbuf);
+		if (evlog->rungroup == NULL)
+		    goto oom;
+	    }
+	}
+    } else {
+	idbuf[0] = '#';
+	strlcpy(&idbuf[1], runas_uid_str, sizeof(idbuf) - 1);
+	free(evlog->runuser);
+	evlog->runuser = strdup(idbuf);
+	if (evlog->runuser == NULL)
+	    goto oom;
+    }
+
+    debug_return_int(
+	iolog_files[IOFD_STDIN].enabled || iolog_files[IOFD_STDOUT].enabled ||
+	iolog_files[IOFD_STDERR].enabled || iolog_files[IOFD_TTYIN].enabled ||
+	iolog_files[IOFD_TTYOUT].enabled);
+oom:
+    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+    debug_return_int(-1);
+}
+
+static int
+sudoers_io_open_local(struct timespec *now)
+{
+    struct eventlog *evlog = iolog_details.evlog;
+    int i, ret = -1;
+    debug_decl(sudoers_io_open_local, SUDOERS_DEBUG_PLUGIN);
+
+    /* If no I/O log path defined we need to figure it out ourselves. */
+    if (evlog->iolog_path == NULL) {
+	int len;
+
+	/* Get next session ID and convert it into a path. */
+	if (!iolog_nextid(_PATH_SUDO_IO_LOGDIR, evlog->sessid)) {
+	    log_warning(SLOG_SEND_MAIL, N_("unable to update sequence file"));
+	    warned = true;
+	    goto done;
+	}
+	len = asprintf(&evlog->iolog_path, "%s/%c%c/%c%c/%c%c",
+	    _PATH_SUDO_IO_LOGDIR,
+	    evlog->sessid[0], evlog->sessid[1], evlog->sessid[2],
+	    evlog->sessid[3], evlog->sessid[4], evlog->sessid[5]);
+	if (len == -1) {
+	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	    goto done;
+	}
+    }
+
+    /*
+     * Create I/O log path along with any intermediate subdirs.
+     * Calls mkdtemp() if iolog_path ends in XXXXXX.
+     */
+    if (!iolog_mkpath(evlog->iolog_path)) {
+	log_warning(SLOG_SEND_MAIL, "%s", evlog->iolog_path);
+	warned = true;
+	goto done;
+    }
+
+    iolog_dir_fd = iolog_openat(AT_FDCWD, evlog->iolog_path, O_RDONLY);
+    if (iolog_dir_fd == -1) {
+	log_warning(SLOG_SEND_MAIL, "%s", evlog->iolog_path);
+	warned = true;
+	goto done;
+    }
+
+    /* Write log file with user and command details. */
+    if (!iolog_write_info_file(iolog_dir_fd, iolog_details.evlog)) {
+	log_warningx(SLOG_SEND_MAIL,
+	    N_("unable to write to I/O log file: %s"), strerror(errno));
+	warned = true;
+	goto done;
+    }
+
+    /* Create the timing and I/O log files. */
+    for (i = 0; i < IOFD_MAX; i++) {
+	if (!iolog_open(&iolog_files[i], iolog_dir_fd, i, "w")) {
+	    log_warning(SLOG_SEND_MAIL, N_("unable to create %s/%s"),
+		evlog->iolog_path, iolog_fd_to_name(i));
+	    warned = true;
+	    goto done;
+	}
+    }
+
+    ret = true;
+
+done:
+    debug_return_int(ret);
+}
+
+#ifdef SUDOERS_LOG_CLIENT
+static int
+sudoers_io_open_remote(struct timespec *now)
+{
+    debug_decl(sudoers_io_open_remote, SUDOERS_DEBUG_PLUGIN);
+
+    /* Open connection to log server, send hello and accept messages. */
+    client_closure = log_server_open(&iolog_details, now, true, SEND_ACCEPT,
+	NULL);
+    if (client_closure != NULL)
+	debug_return_int(1);
+
+    debug_return_int(-1);
+}
+#endif /* SUDOERS_LOG_CLIENT */
+
+static int
+sudoers_io_open(unsigned int version, sudo_conv_t conversation,
+    sudo_printf_t plugin_printf, char * const settings[],
+    char * const user_info[], char * const command_info[],
+    int argc, char * const argv[], char * const user_env[], char * const args[],
+    const char **errstr)
+{
+    struct sudo_conf_debug_file_list debug_files = TAILQ_HEAD_INITIALIZER(debug_files);
+    char * const *cur;
+    const char *cp, *plugin_path = NULL;
+    int ret = -1;
+    debug_decl(sudoers_io_open, SUDOERS_DEBUG_PLUGIN);
+
+    sudo_conv = conversation;
+    sudo_printf = plugin_printf;
+    if (sudoers_io.event_alloc != NULL)
+	plugin_event_alloc = sudoers_io.event_alloc;
+
+    bindtextdomain("sudoers", LOCALEDIR);
+
+    /* Initialize the debug subsystem.  */
+    for (cur = settings; (cp = *cur) != NULL; cur++) {
+	if (strncmp(cp, "debug_flags=", sizeof("debug_flags=") - 1) == 0) {
+	    cp += sizeof("debug_flags=") - 1;
+	    if (!sudoers_debug_parse_flags(&debug_files, cp))
+		debug_return_int(-1);
+	    continue;
+	}
+	if (strncmp(cp, "plugin_path=", sizeof("plugin_path=") - 1) == 0) {
+	    plugin_path = cp + sizeof("plugin_path=") - 1;
+	    continue;
+	}
+    }
+
+    if (!sudoers_debug_register(plugin_path, &debug_files))
+	goto done;
+
+    /* If we have no command (because -V was specified) just return. */
+    if (argc == 0)
+	debug_return_int(true);
+
+    /*
+     * Pull iolog settings out of command_info.
+     */
+    ret = iolog_deserialize_info(&iolog_details, user_info, command_info,
+	argv, user_env);
+    if (ret != true)
+	goto done;
+
+    /* Initialize io_operations. */
+    sudoers_io_setops();
+
+    if (sudo_gettime_awake(&last_time) == -1) {
+	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
+	    "%s: unable to get time of day", __func__);
+	goto done;
+    }
+
+    /*
+     * Create local I/O log file or connect to remote log server.
+     */
+    if ((ret = io_operations.open(&last_time)) != true)
+	goto done;
+
+    /*
+     * Clear I/O log function pointers for disabled log functions.
+     */
+    if (!iolog_files[IOFD_STDIN].enabled)
+	sudoers_io.log_stdin = NULL;
+    if (!iolog_files[IOFD_STDOUT].enabled)
+	sudoers_io.log_stdout = NULL;
+    if (!iolog_files[IOFD_STDERR].enabled)
+	sudoers_io.log_stderr = NULL;
+    if (!iolog_files[IOFD_TTYIN].enabled)
+	sudoers_io.log_ttyin = NULL;
+    if (!iolog_files[IOFD_TTYOUT].enabled)
+	sudoers_io.log_ttyout = NULL;
+
+done:
+    if (ret != true) {
+	if (iolog_dir_fd != -1) {
+	    close(iolog_dir_fd);
+	    iolog_dir_fd = -1;
+	}
+	free_iolog_details();
+	sudo_freepwcache();
+	sudo_freegrcache();
+    }
+
+    /* Ignore errors if they occur if the policy says so. */
+    if (ret == -1 && iolog_details.ignore_log_errors)
+	ret = 0;
+
+    debug_return_int(ret);
+}
+
+static void
+sudoers_io_close_local(int exit_status, int error, const char **errstr)
+{
+    int i;
+    debug_decl(sudoers_io_close_local, SUDOERS_DEBUG_PLUGIN);
+
+    /* Close the files. */
+    for (i = 0; i < IOFD_MAX; i++) {
+	if (iolog_files[i].fd.v == NULL)
+	    continue;
+	iolog_close(&iolog_files[i], errstr);
+    }
+
+    /* Clear write bits from I/O timing file to indicate completion. */
+    if (iolog_dir_fd != -1) {
+	struct stat sb;
+	if (fstatat(iolog_dir_fd, "timing", &sb, 0) != -1) {
+	    CLR(sb.st_mode, S_IWUSR|S_IWGRP|S_IWOTH);
+	    if (fchmodat(iolog_dir_fd, "timing", sb.st_mode, 0) == -1) {
+		sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
+		    "%s: unable to fchmodat timing file", __func__);
+	    }
+	}
+	close(iolog_dir_fd);
+	iolog_dir_fd = -1;
+    }
+
+    debug_return;
+}
+
+#ifdef SUDOERS_LOG_CLIENT
+static void
+sudoers_io_close_remote(int exit_status, int error, const char **errstr)
+{
+    debug_decl(sudoers_io_close_remote, SUDOERS_DEBUG_PLUGIN);
+
+    log_server_close(client_closure, exit_status, error);
+    client_closure = NULL;
+
+    debug_return;
+}
+#endif
+
+static void
+sudoers_io_close(int exit_status, int error)
+{
+    const char *errstr = NULL;
+    debug_decl(sudoers_io_close, SUDOERS_DEBUG_PLUGIN);
+
+    if (io_operations.close != NULL)
+	io_operations.close(exit_status, error, &errstr);
+
+    if (errstr != NULL && !warned) {
+	/* Only warn about I/O log file errors once. */
+	log_warningx(SLOG_SEND_MAIL,
+	    N_("unable to write to I/O log file: %s"), errstr);
+	warned = true;
+    }
+
+    free_iolog_details();
+    sudo_freepwcache();
+    sudo_freegrcache();
+    iolog_pwfilt_free(passprompt_regex_handle);
+    passprompt_regex_handle = NULL;
+
+    /* sudoers_debug_deregister() calls sudo_debug_exit() for us. */
+    sudoers_debug_deregister();
+}
+
+static int
+sudoers_io_version(int verbose)
+{
+    debug_decl(sudoers_io_version, SUDOERS_DEBUG_PLUGIN);
+
+    sudo_printf(SUDO_CONV_INFO_MSG, "Sudoers I/O plugin version %s\n",
+	PACKAGE_VERSION);
+
+    debug_return_int(true);
+}
+
+/*
+ * Write an I/O log entry to the local file system.
+ * Returns 1 on success and -1 on error.
+ * Fills in errstr on error.
+ */
+static int
+sudoers_io_log_local(int event, const char *buf, unsigned int len,
+    struct timespec *delay, const char **errstr)
+{
+    struct iolog_file *iol;
+    char tbuf[1024];
+    char *newbuf = NULL;
+    int ret = -1;
+    debug_decl(sudoers_io_log_local, SUDOERS_DEBUG_PLUGIN);
+
+    if (event < 0 || event >= IOFD_MAX) {
+	*errstr = NULL;
+	sudo_warnx(U_("unexpected I/O event %d"), event);
+	debug_return_int(-1);
+    }
+    iol = &iolog_files[event];
+    if (!iol->enabled) {
+	*errstr = NULL;
+	sudo_warnx(U_("%s: internal error, I/O log file for event %d not open"),
+	    __func__, event);
+	debug_return_int(-1);
+    }
+
+    if (!log_passwords && passprompt_regex_handle != NULL) {
+	if (!iolog_pwfilt_run(passprompt_regex_handle, event, buf, len, &newbuf))
+	    debug_return_int(-1);
+    }
+
+    /* Write I/O log file entry. */
+    if (iolog_write(iol, newbuf ? newbuf : buf, len, errstr) == -1)
+	goto done;
+
+    /* Write timing file entry. */
+    len = (unsigned int)snprintf(tbuf, sizeof(tbuf), "%d %lld.%09ld %u\n",
+	event, (long long)delay->tv_sec, delay->tv_nsec, len);
+    if (len >= sizeof(tbuf)) {
+	/* Not actually possible due to the size of tbuf[]. */
+	*errstr = strerror(EOVERFLOW);
+	goto done;
+    }
+    if (iolog_write(&iolog_files[IOFD_TIMING], tbuf, len, errstr) == -1)
+	goto done;
+
+    /* Success. */
+    ret = 1;
+
+done:
+    free(newbuf);
+    debug_return_int(ret);
+}
+
+#ifdef SUDOERS_LOG_CLIENT
+/*
+ * Schedule an I/O log entry to be written to the log server.
+ * Returns 1 on success and -1 on error.
+ * Fills in errstr on error.
+ */
+static int
+sudoers_io_log_remote(int event, const char *buf, unsigned int len,
+    struct timespec *delay, const char **errstr)
+{
+    int type, ret = -1;
+    debug_decl(sudoers_io_log_remote, SUDOERS_DEBUG_PLUGIN);
+
+    if (client_closure->disabled)
+	debug_return_int(1);
+
+    /* Track elapsed time for comparison with commit points. */
+    sudo_timespecadd(delay, &client_closure->elapsed, &client_closure->elapsed);
+
+    switch (event) {
+    case IO_EVENT_STDIN:
+	type = CLIENT_MESSAGE__TYPE_STDIN_BUF;
+	break;
+    case IO_EVENT_STDOUT:
+	type = CLIENT_MESSAGE__TYPE_STDOUT_BUF;
+	break;
+    case IO_EVENT_STDERR:
+	type = CLIENT_MESSAGE__TYPE_STDERR_BUF;
+	break;
+    case IO_EVENT_TTYIN:
+	type = CLIENT_MESSAGE__TYPE_TTYIN_BUF;
+	break;
+    case IO_EVENT_TTYOUT:
+	type = CLIENT_MESSAGE__TYPE_TTYOUT_BUF;
+	break;
+    default:
+	sudo_warnx(U_("unexpected I/O event %d"), event);
+	goto done;
+    }
+    if (fmt_io_buf(client_closure, type, buf, len, delay)) {
+	ret = client_closure->write_ev->add(client_closure->write_ev,
+	    &iolog_details.server_timeout);
+	if (ret == -1)
+	    sudo_warn("%s", U_("unable to add event to queue"));
+    }
+
+done:
+    debug_return_int(ret);
+}
+#endif /* SUDOERS_LOG_CLIENT */
+
+/*
+ * Generic I/O logging function.  Called by the I/O logging entry points.
+ * Returns 1 on success and -1 on error.
+ */
+static int
+sudoers_io_log(const char *buf, unsigned int len, int event, const char **errstr)
+{
+    struct timespec now, delay;
+    const char *ioerror = NULL;
+    int ret = -1;
+    debug_decl(sudoers_io_log, SUDOERS_DEBUG_PLUGIN);
+
+    if (sudo_gettime_awake(&now) == -1) {
+	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
+	    "%s: unable to get time of day", __func__);
+	ioerror = N_("unable to read the clock");
+	goto bad;
+    }
+    sudo_timespecsub(&now, &last_time, &delay);
+
+    ret = io_operations.log(event, buf, len, &delay, &ioerror);
+
+    last_time.tv_sec = now.tv_sec;
+    last_time.tv_nsec = now.tv_nsec;
+
+bad:
+    if (ret == -1) {
+	if (ioerror != NULL) {
+	    char *cp;
+
+	    if (asprintf(&cp, N_("unable to write to I/O log file: %s"),
+		    ioerror) != -1) {
+		*errstr = cp;
+	    }
+	    if (!warned) {
+		/* Only warn about I/O log file errors once. */
+		log_warningx(SLOG_SEND_MAIL,
+		    N_("unable to write to I/O log file: %s"), ioerror);
+		warned = true;
+	    }
+	}
+
+	/* Ignore errors if they occur if the policy says so. */
+	if (iolog_details.ignore_log_errors)
+	    ret = 1;
+    }
+
+    debug_return_int(ret);
+}
+
+static int
+sudoers_io_log_stdin(const char *buf, unsigned int len, const char **errstr)
+{
+    return sudoers_io_log(buf, len, IO_EVENT_STDIN, errstr);
+}
+
+static int
+sudoers_io_log_stdout(const char *buf, unsigned int len, const char **errstr)
+{
+    return sudoers_io_log(buf, len, IO_EVENT_STDOUT, errstr);
+}
+
+static int
+sudoers_io_log_stderr(const char *buf, unsigned int len, const char **errstr)
+{
+    return sudoers_io_log(buf, len, IO_EVENT_STDERR, errstr);
+}
+
+static int
+sudoers_io_log_ttyin(const char *buf, unsigned int len, const char **errstr)
+{
+    return sudoers_io_log(buf, len, IO_EVENT_TTYIN, errstr);
+}
+
+static int
+sudoers_io_log_ttyout(const char *buf, unsigned int len, const char **errstr)
+{
+    return sudoers_io_log(buf, len, IO_EVENT_TTYOUT, errstr);
+}
+
+static int
+sudoers_io_change_winsize_local(unsigned int lines, unsigned int cols,
+    struct timespec *delay, const char **errstr)
+{
+    char tbuf[1024];
+    int len, ret = -1;
+    debug_decl(sudoers_io_change_winsize_local, SUDOERS_DEBUG_PLUGIN);
+
+    /* Write window change event to the timing file. */
+    len = snprintf(tbuf, sizeof(tbuf), "%d %lld.%09ld %u %u\n",
+	IO_EVENT_WINSIZE, (long long)delay->tv_sec, delay->tv_nsec,
+	lines, cols);
+    if (len < 0 || len >= ssizeof(tbuf)) {
+	/* Not actually possible due to the size of tbuf[]. */
+	*errstr = strerror(EOVERFLOW);
+	goto done;
+    }
+    if (iolog_write(&iolog_files[IOFD_TIMING], tbuf, len, errstr) == -1)
+	goto done;
+
+    /* Success. */
+    ret = 1;
+
+done:
+    debug_return_int(ret);
+}
+
+#ifdef SUDOERS_LOG_CLIENT
+static int
+sudoers_io_change_winsize_remote(unsigned int lines, unsigned int cols,
+    struct timespec *delay, const char **errstr)
+{
+    int ret = -1;
+    debug_decl(sudoers_io_change_winsize_remote, SUDOERS_DEBUG_PLUGIN);
+
+    if (client_closure->disabled)
+	debug_return_int(1);
+
+    /* Track elapsed time for comparison with commit points. */
+    sudo_timespecadd(delay, &client_closure->elapsed, &client_closure->elapsed);
+
+    if (fmt_winsize(client_closure, lines, cols, delay)) {
+	ret = client_closure->write_ev->add(client_closure->write_ev,
+	    &iolog_details.server_timeout);
+	if (ret == -1)
+	    sudo_warn("%s", U_("unable to add event to queue"));
+    }
+
+    debug_return_int(ret);
+}
+#endif /* SUDOERS_LOG_CLIENT */
+
+static int
+sudoers_io_change_winsize(unsigned int lines, unsigned int cols, const char **errstr)
+{
+    struct timespec now, delay;
+    const char *ioerror = NULL;
+    int ret = -1;
+    debug_decl(sudoers_io_change_winsize, SUDOERS_DEBUG_PLUGIN);
+
+    if (sudo_gettime_awake(&now) == -1) {
+	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
+	    "%s: unable to get time of day", __func__);
+	ioerror = N_("unable to read the clock");
+	goto bad;
+    }
+    sudo_timespecsub(&now, &last_time, &delay);
+
+    ret = io_operations.change_winsize(lines, cols, &delay, &ioerror);
+
+    last_time.tv_sec = now.tv_sec;
+    last_time.tv_nsec = now.tv_nsec;
+
+bad:
+    if (ret == -1) {
+	if (ioerror != NULL && !warned) {
+	    char *cp;
+
+	    if (asprintf(&cp, N_("unable to write to I/O log file: %s"),
+		    ioerror) != -1) {
+		*errstr = cp;
+	    }
+	    if (!warned) {
+		/* Only warn about I/O log file errors once. */
+		log_warningx(SLOG_SEND_MAIL,
+		    N_("unable to write to I/O log file: %s"), ioerror);
+		warned = true;
+	    }
+	}
+
+	/* Ignore errors if they occur if the policy says so. */
+	if (iolog_details.ignore_log_errors)
+	    ret = 1;
+    }
+
+    debug_return_int(ret);
+}
+
+static int
+sudoers_io_suspend_local(const char *signame, struct timespec *delay,
+    const char **errstr)
+{
+    unsigned int len;
+    char tbuf[1024];
+    int ret = -1;
+    debug_decl(sudoers_io_suspend_local, SUDOERS_DEBUG_PLUGIN);
+
+    /* Write suspend event to the timing file. */
+    len = (unsigned int)snprintf(tbuf, sizeof(tbuf), "%d %lld.%09ld %s\n",
+	IO_EVENT_SUSPEND, (long long)delay->tv_sec, delay->tv_nsec, signame);
+    if (len >= sizeof(tbuf)) {
+	/* Not actually possible due to the size of tbuf[]. */
+	*errstr = strerror(EOVERFLOW);
+	goto done;
+    }
+    if (iolog_write(&iolog_files[IOFD_TIMING], tbuf, len, errstr) == -1)
+	goto done;
+
+    /* Success. */
+    ret = 1;
+
+done:
+    debug_return_int(ret);
+}
+
+#ifdef SUDOERS_LOG_CLIENT
+static int
+sudoers_io_suspend_remote(const char *signame, struct timespec *delay,
+    const char **errstr)
+{
+    int ret = -1;
+    debug_decl(sudoers_io_suspend_remote, SUDOERS_DEBUG_PLUGIN);
+
+    if (client_closure->disabled)
+	debug_return_int(1);
+
+    /* Track elapsed time for comparison with commit points. */
+    sudo_timespecadd(delay, &client_closure->elapsed, &client_closure->elapsed);
+
+    if (fmt_suspend(client_closure, signame, delay)) {
+	ret = client_closure->write_ev->add(client_closure->write_ev,
+	    &iolog_details.server_timeout);
+	if (ret == -1)
+	    sudo_warn("%s", U_("unable to add event to queue"));
+    }
+
+    debug_return_int(ret);
+}
+#endif /* SUDOERS_LOG_CLIENT */
+
+static int
+sudoers_io_suspend(int signo, const char **errstr)
+{
+    struct timespec now, delay;
+    char signame[SIG2STR_MAX];
+    const char *ioerror = NULL;
+    int ret = -1;
+    debug_decl(sudoers_io_suspend, SUDOERS_DEBUG_PLUGIN);
+
+    if (signo <= 0 || sig2str(signo, signame) == -1) {
+	sudo_warnx(U_("%s: internal error, invalid signal %d"),
+	    __func__, signo);
+	debug_return_int(-1);
+    }
+
+    if (sudo_gettime_awake(&now) == -1) {
+	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
+	    "%s: unable to get time of day", __func__);
+	ioerror = N_("unable to read the clock");
+	goto bad;
+    }
+    sudo_timespecsub(&now, &last_time, &delay);
+
+    /* Write suspend event to the timing file. */
+    ret = io_operations.suspend(signame, &delay, &ioerror);
+
+    last_time.tv_sec = now.tv_sec;
+    last_time.tv_nsec = now.tv_nsec;
+
+bad:
+    if (ret == -1) {
+	if (ioerror != NULL && !warned) {
+	    char *cp;
+
+	    if (asprintf(&cp, N_("unable to write to I/O log file: %s"),
+		    ioerror) != -1) {
+		*errstr = cp;
+	    }
+	    if (!warned) {
+		/* Only warn about I/O log file errors once. */
+		log_warningx(SLOG_SEND_MAIL,
+		    N_("unable to write to I/O log file: %s"), ioerror);
+		warned = true;
+	    }
+	}
+
+	/* Ignore errors if they occur if the policy says so. */
+	if (iolog_details.ignore_log_errors)
+	    ret = 1;
+    }
+
+    debug_return_int(ret);
+}
+
+/*
+ * Fill in the contents of io_operations, either local or remote.
+ */
+static void
+sudoers_io_setops(void)
+{
+    debug_decl(sudoers_io_setops, SUDOERS_DEBUG_PLUGIN);
+
+#ifdef SUDOERS_LOG_CLIENT
+    if (plugin_event_alloc != NULL && iolog_details.log_servers != NULL) {
+	io_operations.open = sudoers_io_open_remote;
+	io_operations.close = sudoers_io_close_remote;
+	io_operations.log = sudoers_io_log_remote;
+	io_operations.change_winsize = sudoers_io_change_winsize_remote;
+	io_operations.suspend = sudoers_io_suspend_remote;
+    } else
+#endif /* SUDOERS_LOG_CLIENT */
+    {
+	io_operations.open = sudoers_io_open_local;
+	io_operations.close = sudoers_io_close_local;
+	io_operations.log = sudoers_io_log_local;
+	io_operations.change_winsize = sudoers_io_change_winsize_local;
+	io_operations.suspend = sudoers_io_suspend_local;
+    }
+
+    debug_return;
+}
+
+sudo_dso_public struct io_plugin sudoers_io = {
+    SUDO_IO_PLUGIN,
+    SUDO_API_VERSION,
+    sudoers_io_open,
+    sudoers_io_close,
+    sudoers_io_version,
+    sudoers_io_log_ttyin,
+    sudoers_io_log_ttyout,
+    sudoers_io_log_stdin,
+    sudoers_io_log_stdout,
+    sudoers_io_log_stderr,
+    NULL, /* register_hooks */
+    NULL, /* deregister_hooks */
+    sudoers_io_change_winsize,
+    sudoers_io_suspend,
+    NULL /* event_alloc() filled in by sudo */
+};