Adding upstream version 1.9.15p5.upstream/1.9.15p5upstream

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

1 files changed, 1184 insertions, 0 deletions

diff --git a/lib/util/sudo_debug.c b/lib/util/sudo_debug.c
new file mode 100644
index 0000000..47a7ba7
--- /dev/null
+++ b/lib/util/sudo_debug.c
@@ -0,0 +1,1184 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 2011-2023 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/stat.h>
+#include <sys/time.h>
+#include <sys/uio.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRINGS_H */
+#include <unistd.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <time.h>
+
+#include <sudo_compat.h>
+#include <sudo_conf.h>
+#include <sudo_debug.h>
+#include <sudo_fatal.h>
+#include <sudo_gettext.h>
+#include <sudo_plugin.h>
+#include <sudo_util.h>
+
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+/*
+ * The debug priorities and subsystems are currently hard-coded.
+ * In the future we might consider allowing plugins to register their
+ * own subsystems and provide direct access to the debugging API.
+ */
+
+/* Note: this must match the order in sudo_debug.h */
+static const char *const sudo_debug_priorities[] = {
+    "crit",
+    "err",
+    "warn",
+    "notice",
+    "diag",
+    "info",
+    "trace",
+    "debug",
+    NULL
+};
+
+/* Note: this must match the order in sudo_debug.h */
+static const char *const sudo_debug_default_subsystems[] = {
+    "args",
+    "conv",
+    "edit",
+    "event",
+    "exec",
+    "hooks",
+    "main",
+    "netif",
+    "pcomm",
+    "plugin",
+    "pty",
+    "selinux",
+    "util",
+    "utmp",
+    NULL
+};
+
+#define NUM_DEF_SUBSYSTEMS	(nitems(sudo_debug_default_subsystems) - 1)
+
+/*
+ * For multiple programs/plugins there is a per-program instance
+ * and one or more outputs (files).
+ */
+struct sudo_debug_output {
+    SLIST_ENTRY(sudo_debug_output) entries;
+    char *filename;
+    int *settings;
+    int fd;
+};
+SLIST_HEAD(sudo_debug_output_list, sudo_debug_output);
+struct sudo_debug_instance {
+    char *program;
+    const char *const *subsystems;
+    const unsigned int *subsystem_ids;
+    unsigned int max_subsystem;
+    unsigned int refcnt;
+    struct sudo_debug_output_list outputs;
+};
+
+/* Support up to 10 instances. */
+#define SUDO_DEBUG_INSTANCE_MAX 10
+static struct sudo_debug_instance *sudo_debug_instances[SUDO_DEBUG_INSTANCE_MAX];
+static int sudo_debug_last_instance = -1;
+
+static char sudo_debug_pidstr[STRLEN_MAX_SIGNED(int) + 3];
+static size_t sudo_debug_pidlen;
+
+#define round_nfds(_n)	(((_n) + (4 * NBBY) - 1) & ~((4 * NBBY) - 1))
+static int sudo_debug_fds_size;
+static unsigned char *sudo_debug_fds;
+static int sudo_debug_max_fd = -1;
+
+/* Default instance index to use for common utility functions. */
+static int sudo_debug_active_instance = -1;
+
+/*
+ * Free the specified output structure.
+ */
+static void
+sudo_debug_free_output(struct sudo_debug_output *output)
+{
+    free(output->filename);
+    free(output->settings);
+    if (output->fd != -1)
+	close(output->fd);
+    free(output);
+}
+
+/*
+ * Create a new output file for the specified debug instance.
+ * Returns NULL if the file cannot be opened or memory cannot be allocated.
+ * XXX - check for duplicates
+ */
+static struct sudo_debug_output *
+sudo_debug_new_output(struct sudo_debug_instance *instance,
+    struct sudo_debug_file *debug_file, int minfd)
+{
+    char *buf, *cp, *last, *subsys, *pri;
+    struct sudo_debug_output *output;
+    unsigned int j;
+    int i;
+
+    /* Create new output for the instance. */
+    /* XXX - reuse fd for existing filename? */
+    output = calloc(1, sizeof(*output));
+    if (output == NULL)
+	goto oom;
+    output->fd = -1;
+    output->settings = reallocarray(NULL, instance->max_subsystem + 1,
+	sizeof(int));
+    if (output->settings == NULL)
+	goto oom;
+    output->filename = strdup(debug_file->debug_file);
+    if (output->filename == NULL)
+	goto oom;
+
+    /* Init per-subsystems settings to -1 since 0 is a valid priority. */
+    for (j = 0; j <= instance->max_subsystem; j++)
+	output->settings[j] = -1;
+
+    /* Open debug file. */
+    output->fd = open(output->filename, O_WRONLY|O_APPEND, S_IRUSR|S_IWUSR);
+    if (output->fd == -1) {
+	/* Create debug file as needed and set group ownership. */
+	if (errno == ENOENT) {
+	    output->fd = open(output->filename, O_WRONLY|O_APPEND|O_CREAT,
+		S_IRUSR|S_IWUSR);
+	}
+	if (output->fd == -1) {
+	    sudo_warn_nodebug("%s", output->filename);
+	    goto bad;
+	}
+	ignore_result(fchown(output->fd, (uid_t)-1, 0));
+    }
+    if (output->fd < minfd) {
+	int newfd = fcntl(output->fd, F_DUPFD, minfd);
+	if (newfd == -1) {
+	    sudo_warn_nodebug("%s", output->filename);
+	    goto bad;
+	}
+	close(output->fd);
+	output->fd = newfd;
+    }
+    if (fcntl(output->fd, F_SETFD, FD_CLOEXEC) == -1) {
+	sudo_warn_nodebug("%s", output->filename);
+	goto bad;
+    }
+    if (sudo_debug_fds_size < output->fd) {
+	/* Bump fds size to the next multiple of 4 * NBBY. */
+	const int old_size = sudo_debug_fds_size / NBBY;
+	const int new_size = round_nfds(output->fd + 1) / NBBY;
+	unsigned char *new_fds;
+
+	new_fds = realloc(sudo_debug_fds, (size_t)new_size);
+	if (new_fds == NULL)
+	    goto oom;
+	memset(new_fds + old_size, 0, (size_t)(new_size - old_size));
+	sudo_debug_fds = new_fds;
+	sudo_debug_fds_size = new_size * NBBY;
+    }
+    sudo_setbit(sudo_debug_fds, output->fd);
+    if (output->fd > sudo_debug_max_fd)
+	sudo_debug_max_fd = output->fd;
+
+    /* Parse Debug conf string. */
+    buf = strdup(debug_file->debug_flags);
+    if (buf == NULL)
+	goto oom;
+    for ((cp = strtok_r(buf, ",", &last)); cp != NULL; (cp = strtok_r(NULL, ",", &last))) {
+	/* Should be in the form subsys@pri. */
+	subsys = cp;
+	if ((pri = strchr(cp, '@')) == NULL)
+	    continue;
+	*pri++ = '\0';
+
+	/* Look up priority and subsystem, fill in sudo_debug_settings[]. */
+	for (i = 0; sudo_debug_priorities[i] != NULL; i++) {
+	    if (strcasecmp(pri, sudo_debug_priorities[i]) == 0) {
+		for (j = 0; instance->subsystems[j] != NULL; j++) {
+		    if (strcasecmp(subsys, "all") == 0) {
+			const unsigned int idx = instance->subsystem_ids ?
+			    SUDO_DEBUG_SUBSYS(instance->subsystem_ids[j]) : j;
+			if (i > output->settings[idx])
+			    output->settings[idx] = i;
+			continue;
+		    }
+		    if (strcasecmp(subsys, instance->subsystems[j]) == 0) {
+			const unsigned int idx = instance->subsystem_ids ?
+			    SUDO_DEBUG_SUBSYS(instance->subsystem_ids[j]) : j;
+			if (i > output->settings[idx])
+			    output->settings[idx] = i;
+			break;
+		    }
+		}
+		break;
+	    }
+	}
+    }
+    free(buf);
+
+    return output;
+oom:
+    // -V:sudo_warn_nodebug:575, 618
+    sudo_warn_nodebug(NULL);
+bad:
+    if (output != NULL)
+	sudo_debug_free_output(output);
+    return NULL;
+}
+
+/*
+ * Register a program/plugin with the debug framework,
+ * parses settings string from sudo.conf and opens debug_files.
+ * If subsystem names are specified they override the default values.
+ * NOTE: subsystems must not be freed by caller unless deregistered.
+ * Sets the active instance to the newly registered instance.
+ * Returns instance index on success, SUDO_DEBUG_INSTANCE_INITIALIZER
+ * if no debug files are specified and SUDO_DEBUG_INSTANCE_ERROR
+ * on error.
+ */
+int
+sudo_debug_register_v2(const char *program, const char *const subsystems[],
+    unsigned int ids[], struct sudo_conf_debug_file_list *debug_files,
+    int minfd)
+{
+    struct sudo_debug_instance *instance = NULL;
+    struct sudo_debug_output *output;
+    struct sudo_debug_file *debug_file;
+    int idx, free_idx = -1;
+    debug_decl_func(sudo_debug_register);
+
+    if (debug_files == NULL)
+	return SUDO_DEBUG_INSTANCE_INITIALIZER;
+
+    /* Use default subsystem names if none are provided. */
+    if (subsystems == NULL) {
+	subsystems = sudo_debug_default_subsystems;
+    } else if (ids == NULL) {
+	/* If subsystems are specified we must have ids[] too. */
+	return SUDO_DEBUG_INSTANCE_ERROR;
+    }
+
+    /* Search for existing instance. */
+    for (idx = 0; idx <= sudo_debug_last_instance; idx++) {
+	if (sudo_debug_instances[idx] == NULL) {
+	    free_idx = idx;
+	    continue;
+	}
+	if (sudo_debug_instances[idx]->subsystems == subsystems &&
+	    strcmp(sudo_debug_instances[idx]->program, program) == 0) {
+	    instance = sudo_debug_instances[idx];
+	    break;
+	}
+    }
+
+    if (instance == NULL) {
+	size_t i;
+	unsigned int j, max_id = NUM_DEF_SUBSYSTEMS - 1;
+
+	/* Fill in subsystem name -> id mapping as needed. */
+	if (ids != NULL) {
+	    for (i = 0; subsystems[i] != NULL; i++) {
+		/* Check default subsystems. */
+		for (j = 0; j < NUM_DEF_SUBSYSTEMS; j++) {
+		    if (strcmp(subsystems[i], sudo_debug_default_subsystems[j]) == 0)
+			break;
+		}
+		if (j == NUM_DEF_SUBSYSTEMS)
+		    j = ++max_id;
+		ids[i] = ((j + 1) << 6);
+	    }
+	}
+
+	if (free_idx != -1)
+	    idx = free_idx;
+	if (idx == SUDO_DEBUG_INSTANCE_MAX) {
+	    /* XXX - realloc? */
+	    sudo_warnx_nodebug("too many debug instances (max %d)", SUDO_DEBUG_INSTANCE_MAX);
+	    return SUDO_DEBUG_INSTANCE_ERROR;
+	}
+	if (idx != sudo_debug_last_instance + 1 && idx != free_idx) {
+	    sudo_warnx_nodebug("%s: instance number mismatch: expected %d or %d, got %d", __func__, sudo_debug_last_instance + 1, free_idx, idx);
+	    return SUDO_DEBUG_INSTANCE_ERROR;
+	}
+	if ((instance = malloc(sizeof(*instance))) == NULL)
+	    return SUDO_DEBUG_INSTANCE_ERROR;
+	if ((instance->program = strdup(program)) == NULL) {
+	    free(instance);
+	    return SUDO_DEBUG_INSTANCE_ERROR;
+	}
+	instance->subsystems = subsystems;
+	instance->subsystem_ids = ids;
+	instance->max_subsystem = max_id;
+	instance->refcnt = 1;
+	SLIST_INIT(&instance->outputs);
+	sudo_debug_instances[idx] = instance;
+	if (idx != free_idx)
+	    sudo_debug_last_instance++;
+    } else {
+	/* Check for matching instance but different ids[]. */
+	if (ids != NULL && instance->subsystem_ids != ids) {
+	    size_t i;
+
+	    for (i = 0; subsystems[i] != NULL; i++)
+		ids[i] = instance->subsystem_ids[i];
+	}
+	instance->refcnt++;
+    }
+
+    TAILQ_FOREACH(debug_file, debug_files, entries) {
+	output = sudo_debug_new_output(instance, debug_file, minfd);
+	if (output != NULL)
+	    SLIST_INSERT_HEAD(&instance->outputs, output, entries);
+    }
+
+    /* Set active instance. */
+    sudo_debug_active_instance = idx;
+
+    /* Stash the pid string so we only have to format it once. */
+    if (sudo_debug_pidlen == 0) {
+	(void)snprintf(sudo_debug_pidstr, sizeof(sudo_debug_pidstr), "[%d] ",
+	    (int)getpid());
+	sudo_debug_pidlen = strlen(sudo_debug_pidstr);
+    }
+
+    return idx;
+}
+
+int
+sudo_debug_register_v1(const char *program, const char *const subsystems[],
+    unsigned int ids[], struct sudo_conf_debug_file_list *debug_files)
+{
+    return sudo_debug_register_v2(program, subsystems, ids, debug_files, -1);
+}
+
+/*
+ * De-register the specified instance from the debug subsystem
+ * and free up any associated data structures.
+ * Returns the number of remaining references for the instance or -1 on error.
+ */
+int
+sudo_debug_deregister_v1(int idx)
+{
+    struct sudo_debug_instance *instance;
+    struct sudo_debug_output *output, *next;
+    debug_decl_func(sudo_debug_deregister);
+
+    if (idx < 0 || idx > sudo_debug_last_instance) {
+	sudo_warnx_nodebug("%s: invalid instance ID %d, max %d",
+	    __func__, idx, sudo_debug_last_instance);
+	return -1;
+    }
+    /* Reset active instance as needed. */
+    if (sudo_debug_active_instance == idx)
+	sudo_debug_active_instance = -1;
+
+    instance = sudo_debug_instances[idx];
+    if (instance == NULL)
+	return -1;			/* already deregistered */
+
+    if (--instance->refcnt != 0)
+	return (int)instance->refcnt;	/* ref held by other caller */
+
+    /* Free up instance data, note that subsystems[] is owned by caller. */
+    sudo_debug_instances[idx] = NULL;
+    SLIST_FOREACH_SAFE(output, &instance->outputs, entries, next) {
+	close(output->fd);
+	free(output->filename);
+	free(output->settings);
+	free(output);
+    }
+    free(instance->program);
+    free(instance);
+
+    if (idx == sudo_debug_last_instance)
+	sudo_debug_last_instance--;
+
+    return 0;
+}
+
+/*
+ * Parse the "filename flags,..." debug_flags entry from sudo.conf
+ * and insert a new sudo_debug_file struct into the list.
+ * Returns 0 on success, 1 on parse error or -1 on malloc failure.
+ */
+int
+sudo_debug_parse_flags_v1(struct sudo_conf_debug_file_list *debug_files,
+    const char *entry)
+{
+    struct sudo_debug_file *debug_file;
+    const char *filename, *flags;
+    size_t namelen;
+
+    /* Only process new-style debug flags: filename flags,... */
+    filename = entry;
+    if (*filename != '/' || (flags = strpbrk(filename, " \t")) == NULL)
+	return 1;
+    namelen = (size_t)(flags - filename);
+    while (isblank((unsigned char)*flags))
+	flags++;
+    if (*flags != '\0') {
+	if ((debug_file = calloc(1, sizeof(*debug_file))) == NULL)
+	    goto oom;
+	if ((debug_file->debug_file = strndup(filename, namelen)) == NULL)
+	    goto oom;
+	if ((debug_file->debug_flags = strdup(flags)) == NULL)
+	    goto oom;
+	TAILQ_INSERT_TAIL(debug_files, debug_file, entries);
+    }
+    return 0;
+oom:
+    if (debug_file != NULL) {
+	free(debug_file->debug_file);
+	free(debug_file->debug_flags);
+	free(debug_file);
+    }
+    return -1;
+}
+
+int
+sudo_debug_get_instance_v1(const char *program)
+{
+    int idx;
+
+    for (idx = 0; idx <= sudo_debug_last_instance; idx++) {
+	if (sudo_debug_instances[idx] == NULL)
+	    continue;
+	if (strcmp(sudo_debug_instances[idx]->program, program) == 0)
+	    return idx;
+    }
+    return SUDO_DEBUG_INSTANCE_INITIALIZER;
+}
+
+pid_t
+sudo_debug_fork_v1(void)
+{
+    pid_t pid;
+
+    if ((pid = fork()) == 0) {
+	(void)snprintf(sudo_debug_pidstr, sizeof(sudo_debug_pidstr), "[%d] ",
+	    (int)getpid());
+	sudo_debug_pidlen = strlen(sudo_debug_pidstr);
+    }
+
+    return pid;
+}
+
+/* Functions versions of sudo_debug_enter* for backwards compatibility. */
+void
+sudo_debug_enter_v1(const char *func, const char *file, int line,
+    unsigned int subsys)
+{
+    sudo_debug_enter(func, file, line, subsys);
+}
+
+void
+sudo_debug_exit_v1(const char *func, const char *file, int line,
+    unsigned int subsys)
+{
+    sudo_debug_exit(func, file, line, subsys);
+}
+
+void
+sudo_debug_exit_int_v1(const char *func, const char *file, int line,
+    unsigned int subsys, int ret)
+{
+    sudo_debug_exit_int(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_uint_v1(const char *func, const char *file, int line,
+    unsigned int subsys, unsigned int ret)
+{
+    sudo_debug_exit_uint(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_long_v1(const char *func, const char *file, int line,
+    unsigned int subsys, long ret)
+{
+    sudo_debug_exit_long(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_id_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, id_t ret)
+{
+    sudo_debug_exit_id_t(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_size_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, size_t ret)
+{
+    sudo_debug_exit_size_t(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_ssize_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, ssize_t ret)
+{
+    sudo_debug_exit_ssize_t(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_time_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, time_t ret)
+{
+    sudo_debug_exit_time_t(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_mode_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, mode_t ret)
+{
+    sudo_debug_exit_mode_t(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_bool_v1(const char *func, const char *file, int line,
+    unsigned int subsys, bool ret)
+{
+    sudo_debug_exit_bool(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_str_v1(const char *func, const char *file, int line,
+    unsigned int subsys, const char *ret)
+{
+    sudo_debug_exit_str(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_str_masked_v1(const char *func, const char *file, int line,
+    unsigned int subsys, const char *ret)
+{
+    sudo_debug_exit_str_masked(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_exit_ptr_v1(const char *func, const char *file, int line,
+    unsigned int subsys, const void *ret)
+{
+    sudo_debug_exit_ptr(func, file, line, subsys, ret);
+}
+
+void
+sudo_debug_write2_v1(int fd, const char *func, const char *file, int lineno,
+    const char *str, unsigned int len, int errnum)
+{
+    char numbuf[(((sizeof(int) * 8) + 2) / 3) + 2];
+    char timebuf[64];
+    struct timeval tv;
+    struct iovec iov[12];
+    int iovcnt = 3;
+
+    /* Cannot use sudo_gettime_real() here since it calls sudo_debug. */
+    timebuf[0] = '\0';
+    if (gettimeofday(&tv, NULL) != -1) {
+	time_t now = tv.tv_sec;
+	struct tm tm;
+	size_t tlen;
+	if (localtime_r(&now, &tm) != NULL) {
+	    timebuf[sizeof(timebuf) - 1] = '\0';
+	    tlen = strftime(timebuf, sizeof(timebuf), "%b %e %H:%M:%S", &tm);
+	    if (tlen == 0 || timebuf[sizeof(timebuf) - 1] != '\0') {
+		/* contents are undefined on error */
+		timebuf[0] = '\0';
+	    } else {
+		(void)snprintf(timebuf + tlen, sizeof(timebuf) - tlen,
+		    ".%03d ", (int)tv.tv_usec / 1000);
+	    }
+	}
+    }
+    iov[0].iov_base = timebuf;
+    iov[0].iov_len = strlen(timebuf);
+
+    /* Prepend program name and pid with a trailing space. */
+    iov[1].iov_base = (char *)getprogname();
+    iov[1].iov_len = strlen(iov[1].iov_base);
+    iov[2].iov_base = sudo_debug_pidstr;
+    iov[2].iov_len = sudo_debug_pidlen;
+
+    /* Add string, trimming any trailing newlines. */
+    while (len > 0 && str[len - 1] == '\n')
+	len--;
+    if (len != 0) {
+	iov[iovcnt].iov_base = (char *)str;
+	iov[iovcnt].iov_len = len;
+	iovcnt++;
+    }
+
+    /* Append error string if errno is specified. */
+    if (errnum) {
+	if (len != 0) {
+	    iov[iovcnt].iov_base = (char *)": ";
+	    iov[iovcnt].iov_len = 2;
+	    iovcnt++;
+	}
+	iov[iovcnt].iov_base = strerror(errnum);
+	iov[iovcnt].iov_len = strlen(iov[iovcnt].iov_base);
+	iovcnt++;
+    }
+
+    /* If function, file and lineno are specified, append them. */
+    if (func != NULL && file != NULL && lineno != 0) {
+	iov[iovcnt].iov_base = (char *)" @ ";
+	iov[iovcnt].iov_len = 3;
+	iovcnt++;
+
+	iov[iovcnt].iov_base = (char *)func;
+	iov[iovcnt].iov_len = strlen(func);
+	iovcnt++;
+
+	iov[iovcnt].iov_base = (char *)"() ";
+	iov[iovcnt].iov_len = 3;
+	iovcnt++;
+
+	iov[iovcnt].iov_base = (char *)file;
+	iov[iovcnt].iov_len = strlen(file);
+	iovcnt++;
+
+	(void)snprintf(numbuf, sizeof(numbuf), ":%d", lineno);
+	iov[iovcnt].iov_base = numbuf;
+	iov[iovcnt].iov_len = strlen(numbuf);
+	iovcnt++;
+    }
+
+    /* Append newline. */
+    iov[iovcnt].iov_base = (char *)"\n";
+    iov[iovcnt].iov_len = 1;
+    iovcnt++;
+
+    /* Write message in a single syscall */
+    ignore_result(writev(fd, iov, iovcnt));
+}
+
+bool
+sudo_debug_needed_v1(unsigned int level)
+{
+    unsigned int subsys;
+    int pri;
+    struct sudo_debug_instance *instance;
+    struct sudo_debug_output *output;
+    bool result = false;
+
+    if (sudo_debug_active_instance == -1)
+        goto out;
+
+    /* Extract priority and subsystem from level. */
+    pri = (int)SUDO_DEBUG_PRI(level);
+    subsys = SUDO_DEBUG_SUBSYS(level);
+
+    if (sudo_debug_active_instance > sudo_debug_last_instance)
+        goto out;
+
+    instance = sudo_debug_instances[sudo_debug_active_instance];
+    if (instance == NULL)
+        goto out;
+
+    if (subsys <= instance->max_subsystem) {
+        SLIST_FOREACH(output, &instance->outputs, entries) {
+            if (output->settings[subsys] >= pri) {
+                result = true;
+                break;
+            }
+        }
+    }
+out:
+    return result;
+}
+
+void
+sudo_debug_vprintf2_v1(const char *func, const char *file, int lineno,
+    unsigned int level, const char * restrict fmt, va_list ap)
+{
+    int pri, saved_errno = errno;
+    unsigned int subsys;
+    char static_buf[1024], *buf = static_buf;
+    struct sudo_debug_instance *instance;
+    struct sudo_debug_output *output;
+    debug_decl_func(sudo_debug_vprintf2);
+
+    if (sudo_debug_active_instance == -1)
+	goto out;
+
+    /* Extract priority and subsystem from level. */
+    pri = (int)SUDO_DEBUG_PRI(level);
+    subsys = SUDO_DEBUG_SUBSYS(level);
+
+    /* Disable extra info if SUDO_DEBUG_LINENO is not enabled. */
+    if (!ISSET(level, SUDO_DEBUG_LINENO)) {
+	func = NULL;
+	file = NULL;
+	lineno = 0;
+    }
+
+    /* Find matching instance. */
+    if (sudo_debug_active_instance > sudo_debug_last_instance) {
+	sudo_warnx_nodebug("%s: invalid instance ID %d, max %d",
+	    __func__, sudo_debug_active_instance, sudo_debug_last_instance);
+	goto out;
+    }
+    instance = sudo_debug_instances[sudo_debug_active_instance];
+    if (instance == NULL) {
+	sudo_warnx_nodebug("%s: unregistered instance index %d", __func__,
+	    sudo_debug_active_instance);
+	goto out;
+    }
+
+    SLIST_FOREACH(output, &instance->outputs, entries) {
+	/* Make sure we want debug info at this level. */
+	if (subsys <= instance->max_subsystem && output->settings[subsys] >= pri) {
+	    int errcode, buflen = 0;
+	    va_list ap2;
+
+	    if (fmt != NULL) {
+		/* Operate on a copy of ap to support multiple outputs. */
+		va_copy(ap2, ap);
+		buflen = vsnprintf(static_buf, sizeof(static_buf), fmt, ap2);
+		va_end(ap2);
+		if (buflen < 0) {
+		    sudo_warnx_nodebug("%s: invalid format string \"%s\"",
+			__func__, fmt);
+		    buflen = 0;
+		} else if (buflen >= ssizeof(static_buf)) {
+		    /* Not enough room in static buf, allocate dynamically. */
+		    va_copy(ap2, ap);
+		    buflen = vasprintf(&buf, fmt, ap2);
+		    if (buflen == -1) {
+			buf = static_buf;
+			buflen = (int)strlen(buf);
+		    }
+		    va_end(ap2);
+		}
+	    }
+	    errcode = ISSET(level, SUDO_DEBUG_ERRNO) ? saved_errno : 0;
+	    sudo_debug_write2(output->fd, func, file, lineno, buf,
+		(unsigned int)buflen, errcode);
+	    if (buf != static_buf) {
+		free(buf);
+		buf = static_buf;
+	    }
+	}
+    }
+out:
+    errno = saved_errno;
+}
+
+#ifdef NO_VARIADIC_MACROS
+void
+sudo_debug_printf_nvm_v1(int pri, const char * restrict fmt, ...)
+{
+    va_list ap;
+
+    va_start(ap, fmt);
+    sudo_debug_vprintf2(NULL, NULL, 0, pri, fmt, ap);
+    va_end(ap);
+}
+#endif /* NO_VARIADIC_MACROS */
+
+void
+sudo_debug_printf2_v1(const char *func, const char *file, int lineno,
+    unsigned int level, const char * restrict fmt, ...)
+{
+    va_list ap;
+
+    va_start(ap, fmt);
+    sudo_debug_vprintf2(func, file, lineno, level, fmt, ap);
+    va_end(ap);
+}
+
+#define EXEC_PREFIX "exec "
+
+void
+sudo_debug_execve2_v1(unsigned int level, const char *path, char *const argv[],
+    char *const envp[])
+{
+    int pri, saved_errno = errno;
+    unsigned int subsys;
+    struct sudo_debug_instance *instance;
+    struct sudo_debug_output *output;
+    char * const *av;
+    char *cp, static_buf[4096], *buf = static_buf;
+    size_t buflen, plen;
+    debug_decl_func(sudo_debug_execve2);
+
+    if (sudo_debug_active_instance == -1 || path == NULL)
+	goto out;
+
+    /* Extract priority and subsystem from level. */
+    pri = (int)SUDO_DEBUG_PRI(level);
+    subsys = SUDO_DEBUG_SUBSYS(level);
+
+    /* Find matching instance. */
+    if (sudo_debug_active_instance > sudo_debug_last_instance) {
+	sudo_warnx_nodebug("%s: invalid instance ID %d, max %d",
+	    __func__, sudo_debug_active_instance, sudo_debug_last_instance);
+	goto out;
+    }
+    instance = sudo_debug_instances[sudo_debug_active_instance];
+    if (instance == NULL) {
+	sudo_warnx_nodebug("%s: unregistered instance index %d", __func__,
+	    sudo_debug_active_instance);
+	goto out;
+    }
+    if (subsys > instance->max_subsystem)
+	goto out;
+
+    SLIST_FOREACH(output, &instance->outputs, entries) {
+	bool log_envp = false;
+
+	/* Make sure we want debug info at this level. */
+	if (output->settings[subsys] < pri)
+	    continue;
+
+	/* Log envp for debug level "debug". */
+	if (output->settings[subsys] >= SUDO_DEBUG_DEBUG - 1 && envp != NULL)
+	    log_envp = true;
+
+	/* Alloc and build up buffer. */
+	plen = strlen(path);
+	buflen = sizeof(EXEC_PREFIX) -1 + plen;
+	if (argv != NULL && argv[0] != NULL) {
+	    buflen += sizeof(" []") - 1;
+	    for (av = argv; *av; av++)
+		buflen += strlen(*av) + 1;
+	    buflen--;
+	}
+	if (log_envp && envp[0] != NULL) {
+	    buflen += sizeof(" []") - 1;
+	    for (av = envp; *av; av++)
+		buflen += strlen(*av) + 1;
+	    buflen--;
+	}
+	if (buflen >= sizeof(static_buf)) {
+	    buf = malloc(buflen + 1);
+	    if (buf == NULL)
+		goto out;
+	}
+
+	/* Copy prefix and command. */
+	memcpy(buf, EXEC_PREFIX, sizeof(EXEC_PREFIX) - 1);
+	cp = buf + sizeof(EXEC_PREFIX) - 1;
+	memcpy(cp, path, plen);
+	cp += plen;
+
+	/* Copy argv. */
+	if (argv != NULL && argv[0] != NULL) {
+	    *cp++ = ' ';
+	    *cp++ = '[';
+	    for (av = argv; *av; av++) {
+		size_t avlen = strlen(*av);
+		memcpy(cp, *av, avlen);
+		cp += avlen;
+		*cp++ = ' ';
+	    }
+	    cp[-1] = ']';
+	}
+
+	if (log_envp && envp[0] != NULL) {
+	    *cp++ = ' ';
+	    *cp++ = '[';
+	    for (av = envp; *av; av++) {
+		size_t avlen = strlen(*av);
+		memcpy(cp, *av, avlen);
+		cp += avlen;
+		*cp++ = ' ';
+	    }
+	    cp[-1] = ']';
+	}
+
+	*cp = '\0';
+
+	sudo_debug_write(output->fd, buf, (unsigned int)buflen, 0);
+	if (buf != static_buf) {
+	    free(buf);
+	    buf = static_buf;
+	}
+    }
+out:
+    errno = saved_errno;
+}
+
+/*
+ * Returns the active instance or SUDO_DEBUG_INSTANCE_INITIALIZER
+ * if no instance is active.
+ */
+int
+sudo_debug_get_active_instance_v1(void)
+{
+    return sudo_debug_active_instance;
+}
+
+/*
+ * Sets a new active instance, returning the old one.
+ * Note that the old instance may be SUDO_DEBUG_INSTANCE_INITIALIZER
+ * if this is the only instance.
+ */
+int
+sudo_debug_set_active_instance_v1(int idx)
+{
+    const int old_idx = sudo_debug_active_instance;
+
+    if (idx >= -1 && idx <= sudo_debug_last_instance)
+	sudo_debug_active_instance = idx;
+    return old_idx;
+}
+
+/*
+ * Replace the ofd with nfd in all outputs if present.
+ * Also updates sudo_debug_fds.
+ */
+void
+sudo_debug_update_fd_v1(int ofd, int nfd)
+{
+    int idx;
+
+    if (ofd <= sudo_debug_max_fd && sudo_isset(sudo_debug_fds, ofd)) {
+	/* Update sudo_debug_fds. */
+	sudo_clrbit(sudo_debug_fds, ofd);
+	sudo_setbit(sudo_debug_fds, nfd);
+
+	/* Update the outputs. */
+	for (idx = 0; idx <= sudo_debug_last_instance; idx++) {
+	    struct sudo_debug_instance *instance;
+	    struct sudo_debug_output *output;
+
+	    instance = sudo_debug_instances[idx];
+	    if (instance == NULL)
+		continue;
+	    SLIST_FOREACH(output, &instance->outputs, entries) {
+		if (output->fd == ofd)
+		    output->fd = nfd;
+	    }
+	}
+    }
+}
+
+/*
+ * Returns the highest debug output fd or -1 if no debug files open.
+ * Fills in fds with the value of sudo_debug_fds.
+ */
+int
+sudo_debug_get_fds_v1(unsigned char **fds)
+{
+    *fds = sudo_debug_fds;
+    return sudo_debug_max_fd;
+}
+#else /* FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION */
+int
+sudo_debug_register_v2(const char *program, const char *const subsystems[],
+    unsigned int ids[], struct sudo_conf_debug_file_list *debug_files,
+    int minfd)
+{
+    return SUDO_DEBUG_INSTANCE_INITIALIZER;
+}
+
+int
+sudo_debug_register_v1(const char *program, const char *const subsystems[],
+    unsigned int ids[], struct sudo_conf_debug_file_list *debug_files)
+{
+    return SUDO_DEBUG_INSTANCE_INITIALIZER;
+}
+
+int
+sudo_debug_deregister_v1(int idx)
+{
+    return -1;
+}
+
+int
+sudo_debug_parse_flags_v1(struct sudo_conf_debug_file_list *debug_files,
+    const char *entry)
+{
+    return 0;
+}
+
+int
+sudo_debug_get_instance_v1(const char *program)
+{
+    return SUDO_DEBUG_INSTANCE_INITIALIZER;
+}
+
+pid_t
+sudo_debug_fork_v1(void)
+{
+    return fork();
+}
+
+void
+sudo_debug_enter_v1(const char *func, const char *file, int line,
+    unsigned int subsys)
+{
+}
+
+void
+sudo_debug_exit_v1(const char *func, const char *file, int line,
+    unsigned int subsys)
+{
+}
+
+void
+sudo_debug_exit_int_v1(const char *func, const char *file, int line,
+    unsigned int subsys, int ret)
+{
+}
+
+void
+sudo_debug_exit_uint_v1(const char *func, const char *file, int line,
+    unsigned int subsys, unsigned int ret)
+{
+}
+
+void
+sudo_debug_exit_long_v1(const char *func, const char *file, int line,
+    unsigned int subsys, long ret)
+{
+}
+
+void
+sudo_debug_exit_id_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, id_t ret)
+{
+}
+
+void
+sudo_debug_exit_size_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, size_t ret)
+{
+}
+
+void
+sudo_debug_exit_ssize_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, ssize_t ret)
+{
+}
+
+void
+sudo_debug_exit_time_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, time_t ret)
+{
+}
+
+void
+sudo_debug_exit_mode_t_v1(const char *func, const char *file, int line,
+    unsigned int subsys, mode_t ret)
+{
+}
+
+void
+sudo_debug_exit_bool_v1(const char *func, const char *file, int line,
+    unsigned int subsys, bool ret)
+{
+}
+
+void
+sudo_debug_exit_str_v1(const char *func, const char *file, int line,
+    unsigned int subsys, const char *ret)
+{
+}
+
+void
+sudo_debug_exit_str_masked_v1(const char *func, const char *file, int line,
+    unsigned int subsys, const char *ret)
+{
+}
+
+void
+sudo_debug_exit_ptr_v1(const char *func, const char *file, int line,
+    unsigned int subsys, const void *ret)
+{
+}
+
+void
+sudo_debug_write2_v1(int fd, const char *func, const char *file, int lineno,
+    const char *str, unsigned int len, int errnum)
+{
+}
+
+bool
+sudo_debug_needed_v1(unsigned int level)
+{
+    return false;
+}
+
+void
+sudo_debug_vprintf2_v1(const char *func, const char *file, int lineno,
+    unsigned int level, const char * restrict fmt, va_list ap)
+{
+}
+
+#ifdef NO_VARIADIC_MACROS
+void
+sudo_debug_printf_nvm_v1(int pri, const char * restrict fmt, ...)
+{
+}
+#endif /* NO_VARIADIC_MACROS */
+
+void
+sudo_debug_printf2_v1(const char *func, const char *file, int lineno,
+    unsigned int level, const char * restrict fmt, ...)
+{
+}
+
+void
+sudo_debug_execve2_v1(unsigned int level, const char *path, char *const argv[],
+    char *const envp[])
+{
+}
+
+int
+sudo_debug_get_active_instance_v1(void)
+{
+    return SUDO_DEBUG_INSTANCE_INITIALIZER;
+}
+
+int
+sudo_debug_set_active_instance_v1(int idx)
+{
+    return SUDO_DEBUG_INSTANCE_INITIALIZER;
+}
+
+void
+sudo_debug_update_fd_v1(int ofd, int nfd)
+{
+}
+
+int
+sudo_debug_get_fds_v1(unsigned char **fds)
+{
+    return -1;
+}
+#endif /* FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION */