confd: replace sysrepo-plugind + bootstrap + load with single daemon

On single-core Cortex-A7, the YANG bootstrap and config loading is the
dominant boot bottleneck.  The current sequence spawns three serial
phases (bootstrap, sysrepo-plugind, load), each performing independent
sr_connect()/sr_disconnect() cycles, and every sysrepoctl/sysrepocfg
invocation is a fork+exec that rebuilds SHM from scratch.

Replace all three with a single confd binary that does one sr_connect()
and performs all datastore operations in-process:

 - Wipe stale /dev/shm/sr_* for a clean slate
 - sr_install_factory_config() from the generated JSON
 - Smart migration: compare config version via libjansson, only
   fork+exec the migrate script when versions actually differ
 - Load startup-config (or test-config) via lyd_parse_data() +
   sr_replace_config(), mirroring what sysrepocfg -I does internally
 - On failure: revert to factory-default, load failure-config, set
   login banners (Fail Secure mode)
 - On first boot: copy factory-default to running, export to file
 - dlopen plugins and enter event loop

The bootstrap shell script is split: config generation (gen-hostname,
gen-interfaces, etc.) stays in the new gen-config script, while all
sysrepo operations move into the C daemon.  The finit boot sequence
collapses from 5 stanzas to 2 (gen-config -> confd).

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

board/common/rootfs/usr/libexec/infix/init.d/30-cfg-migrate

@@ -1,20 +0,0 @@
-#!/bin/sh
-# Check if /cfg/startup-config.cfg needs to be migrated to new syntax.
-# Backup of the original is created in /cfg/backup/ for old versions,
-# the migrate tool inserts old version in name before .cfg extension.
-CONFIG_FILE="/cfg/startup-config.cfg"
-BACKUP_FILE="/cfg/backup/startup-config.cfg"
-BACKUP_DIR="$(dirname "$BACKUP_FILE")"
-
-mkdir -p         "$BACKUP_DIR"
-chown root:wheel "$BACKUP_DIR"
-chmod 0770       "$BACKUP_DIR"
-
-if [ ! -f "$CONFIG_FILE" ]; then
-    logger -I $$ -k -p user.notice -t $(basename "$0")  "No $(basename "$CONFIG_FILE" .cfg) yet, likely factory reset."
-    exit 0
-elif migrate -cq "$CONFIG_FILE"; then
-    exit 0
-fi
-
-migrate -i -b "$BACKUP_FILE" "$CONFIG_FILE"

package/confd/confd.conf

@@ -1,27 +1,19 @@
 #set DEBUG=1
 
+# Phase 1: Generate factory/failure/test configs (shell)
 run name:bootstrap log:prio:user.notice norestart <usr/ixinit> \
-	[S] /usr/libexec/confd/bootstrap \
+	[S] /usr/libexec/confd/gen-config \
-	-- Bootstrapping YANG datastore
+	-- Generating factory configuration
 
 run name:error :1 log:console norestart if:<run/bootstrap/failure> \
 	[S] /usr/libexec/confd/error --
 
-service name:confd log:prio:daemon.err <run/bootstrap/success> \
+# Phase 2: Single daemon handles datastore init, config load, and plugins
-	[S12345] sysrepo-plugind -f -p /run/confd.pid -n -v warning \
+#  log:prio:daemon.err
+service name:confd <run/bootstrap/success> env:/etc/default/confd \
+	[S12345] confd -f -n -v warning -p /run/confd.pid \
+		-F /etc/factory-config.cfg \
+		-S /cfg/startup-config.cfg \
+		-E /etc/failure-config.cfg \
+		-t $CONFD_TIMEOUT \
 	-- Configuration daemon
-
-# Bootstrap system with startup-config
-run name:startup log:prio:user.notice norestart <pid/confd> env:/etc/default/confd \
-	[S] /usr/libexec/confd/load -t $CONFD_TIMEOUT startup-config \
-	-- Loading startup-config
-
-# Run if loading startup-config fails for some reason
-run	name:failure log:prio:user.crit norestart env:/etc/default/confd \
-	if:<run/startup/failure> \
-	[S] <pid/confd> /usr/libexec/confd/load -t $CONFD_TIMEOUT failure-config \
-	-- Loading failure-config
-
-run	name:error :2 log:console norestart \
-	if:<run/failure/failure> \
-	[S] /usr/libexec/confd/error --

src/confd/bin/Makefile.am

@@ -1,4 +1,3 @@
-pkglibexec_SCRIPTS = bootstrap error load gen-hostname \
+pkglibexec_SCRIPTS = gen-hostname gen-interfaces gen-motd gen-hardware \
-		     gen-interfaces gen-motd gen-hardware gen-version \
+		     gen-version mstpd-wait-online wait-interface
-		     mstpd-wait-online wait-interface
 sbin_SCRIPTS       = dagger migrate firewall

src/confd/bin/gen-config

@@ -1,42 +1,32 @@
 #!/bin/sh
-# Bootstrap system factory-config, failure-config, test-config and sysrepo db.
+# Generate factory-config, failure-config, and test-config files.
 #
-########################################################################
+# These configs are derived from default settings snippets in
-# The system factory-config, failure-config and test-config are derived
+# /usr/share/confd/factory.d, and generated snippets (e.g., hostname
-# from default settings snippets, from /usr/share/confd/factory.d, and
+# based on base MAC address, number of interfaces).
-# some generated snippets, e.g., hostname (based on base MAC address)
-# and number of interfaces.
 #
-# The resulting factory-config is used to create the syrepo db (below)
+# The sysrepo datastore operations (loading factory defaults, startup
-# {factory} datastore.  Hence, the factory-config file must match the
+# config, migration) are handled by the confd daemon.
-# the YANG models of the active image.
 ########################################################################
 # NOTE: with the Infix defaults, a br2-external can provide a build-time
 #       /etc/factory-config.cfg to override the behavior of this script.
 #
 #       This applies also for /etc/failure-config.cfg, but we recommend
 #       strongly that you instead provide gen-err-custom, see below.
-#
-# TODO: Look for statically defined factory-config, based on system's
-#       product ID, or just custom site-specific factory on /cfg.
 ########################################################################
-STATUS=""
 
 # Log functions
-critical()
-{
-    logger -i -p user.crit -t bootstrap "$1" 2>/dev/null || echo "$1"
-}
-
 err()
 {
-    logger -i -p user.err -t bootstrap "$1" 2>/dev/null || echo "$1"
+    logger -i -p user.err -t gen-config "$1" 2>/dev/null || echo "$1"
 }
 
-# When logging errors, generating /etc/issue* or /etc/banner (SSH)
+log()
-. /etc/os-release
+{
+    logger -i -p user.notice -t gen-config "$1" 2>/dev/null || echo "$1"
+}
 
-# /etc/confdrc controls the behavior or most of the gen-scripts,
+# /etc/confdrc controls the behavior of most of the gen-scripts,
 # customize in an overlay when using Infix as an br2-external.
 RC=/etc/confdrc
 if [ "$1" = "-f" ] && [ -f "$2" ]; then
@@ -79,25 +69,6 @@ collate()
     fi
 }
 
-# Report error on console, syslog, and set login banners for getty + ssh
-console_error()
-{
-    critical "$1"
-
-    # shellcheck disable=SC3037
-    /bin/echo -e "\n\n\e[31mCRITICAL BOOTSTRAP ERROR\n$1\e[0m\n" > /dev/console
-
-    [ -z "$STATUS" ] || return
-    STATUS="CRITICAL ERROR: $1"
-
-    printf "\n$STATUS\n" | tee -a \
-			       /etc/banner \
-			       /etc/issue \
-			       /etc/issue.net \
-			       >/dev/null
-    return 0
-}
-
 gen_factory_cfg()
 {
     # Fetch defaults, simplifies sort in collate()
@@ -145,49 +116,18 @@ gen_test_cfg()
     collate "$TEST_GEN" "$TEST_CFG" "$TEST_D"
 }
 
-# Both factory-config and failure-config are generated every boot
+log "Starting up, calling gen_factory_cfg()"
-# regardless if there is a static /etc/factory-config.cfg or not.
 gen_factory_cfg
+log "Starting up, calling gen_failure_cfg()"
 gen_failure_cfg
 
 if [ -f "/mnt/aux/test-mode" ]; then
     gen_test_cfg
-    sysrepoctl -c infix-test -e test-mode-enable
 fi
 
-if [ -n "$TESTING" ]; then
+# Ensure 'admin' group users always have access to /cfg
-	echo "Done."
+mkdir -p "$CFG_PATH_"
-	exit 0
+chgrp wheel "$CFG_PATH_" 2>/dev/null
-fi
+chmod g+w   "$CFG_PATH_" 2>/dev/null
-mkdir -p /etc/sysrepo/
-if [ -f "$FACTORY_CFG" ]; then
-    cp "$FACTORY_CFG" "$INIT_DATA"
-else
-    cp "$FAILURE_CFG" "$INIT_DATA"
-fi
-rc=$?
 
-# Ensure 'admin' group users always have access
+log "All done."
-chgrp wheel "$CFG_PATH_"
-chmod g+w   "$CFG_PATH_"
-
-# Ensure factory-config has correct syntax
-if ! migrate -cq "$INIT_DATA"; then
-    if migrate -iq -b "${INIT_DATA%.*}.bak" "$INIT_DATA"; then
-	err "${INIT_DATA}: found and fixed old syntax!"
-    fi
-fi
-
-if ! sysrepoctl -z "$INIT_DATA"; then
-    rc=$?
-    err "Failed loading factory-default datastore"
-else
-    # Clear running-config so we can load/create startup in the next step
-    temp=$(mktemp)
-    echo "{}" > "$temp"
-    sysrepocfg -f json -I"$temp" -d running
-    rc=$?
-    rm "$temp"
-fi
-
-exit $rc

src/confd/bin/load

@@ -1,143 +0,0 @@
-#!/bin/sh
-# load [-b] <startup-config | failure-config | test-config>
-#
-# Import a configuration to the sysrepo datastore using `sysrepocfg -Ifile`
-#
-# If the '-b' option is used we set the Finit <usr/bootstrap> condition if
-# sysrepocfg returns OK.  This to be able to detect and trigger the Infix
-# Fail Secure Mode at boot.
-#
-
-banner_append()
-{
-    printf "\n%s\n" "$*" | tee -a \
-			  /etc/banner \
-			  /etc/issue \
-			  /etc/issue.net \
-			  >/dev/null
-    return 0
-}
-
-# Ensure correct ownership and permissions, in particular after factory reset
-# Created by the system, writable by any user in the admin group.
-perms()
-{
-    chown root:wheel "$1"
-    chmod 0660 "$1"
-}
-
-note()
-{
-    msg="$*"
-    logger -I $$ -p user.notice -t load -- "$msg"
-}
-
-err()
-{
-    msg="$*"
-    logger -I $$ -p user.error -t load -- "$msg"
-}
-
-
-# shellcheck disable=SC1091
-. /etc/confdrc
-
-sysrepocfg=sysrepocfg
-while getopts "t:" opt; do
-    case ${opt} in
-	t)
-	    sysrepocfg="$sysrepocfg -t $OPTARG"
-	    ;;
-	*)
-	    ;;
-    esac
-done
-shift $((OPTIND - 1))
-
-if [ $# -lt 1 ]; then
-    err "No configuration file supplied"
-    exit 1
-fi
-
-
-config=$1
-
-if [ -f "/mnt/aux/test-mode" ] && [ "$config" = "startup-config" ]; then
-
-    if [ -f "/mnt/aux/test-override-startup" ]; then
-	rm -f "/mnt/aux/test-override-startup"
-    else
-    	note "Test mode detected, switching to test-config"
-    	config="test-config"
-    fi
-fi
-
-if [ -f "$config" ]; then
-    fn="$config"
-else
-    if [ -f "$CFG_PATH_/${config}.cfg" ]; then
-	fn="$CFG_PATH_/${config}.cfg"
-    else
-	fn="$SYS_PATH_/${config}.cfg"
-    fi
-fi
-
-if [ ! -f "$fn" ]; then
-    case "$config" in
-	startup-config)
-	    note "startup-config missing, initializing running datastore from factory-config"
-	    $sysrepocfg -C factory-default
-	    rc=$?
-	    note "saving factory-config to $STARTUP_CFG ..."
-	    $sysrepocfg -f json -X"$STARTUP_CFG"
-	    perms "$STARTUP_CFG"
-	    exit $rc
-	    ;;
-	*)
-	    err "No such file, $fn, aborting!"
-	    exit 1
-	    ;;
-    esac
-fi
-
-note "Loading $config ..."
-if ! $sysrepocfg -v2 -I"$fn" -f json; then
-    case "$config" in
-	startup-config)
-	    err "Failed loading $fn, reverting to Fail Secure mode!"
-	    # On failure to load startup-config the system is in an undefined state
-	    cat <<-EOF >/tmp/factory.json
-		{
-		   "infix-factory-default:factory-default": {}
-		}
-		EOF
-
-	    if ! $sysrepocfg -f json -R /tmp/factory.json; then
-		rm -f /etc/sysrepo/data/*startup*
-		rm -f /etc/sysrepo/data/*running*
-		rm -f /dev/shm/sr_*
-		killall sysrepo-plugind
-	    fi
-	    ;;
-	failure-config)
-	    err "Failed loading $fn, aborting!"
-	    banner_append "CRITICAL ERROR: Logins are disabled, no credentials available"
-	    initctl -nbq runlevel 9
-	    ;;
-	*)
-	    err "Unknown config $config, aborting!"
-	    ;;
-    esac
-
-    exit 1
-else
-    note "Success, syncing with startup datastore."
-    $sysrepocfg -v2 -d startup -C running
-fi
-
-note "Loaded $fn successfully."
-if [ "$config" = "failure-config" ]; then
-    banner_append "ERROR: Corrupt startup-config, system has reverted to default login credentials"
-else
-    perms "$fn"
-fi

src/confd/configure.ac

@@ -84,7 +84,8 @@ PKG_CHECK_MODULES([crypt],   [libxcrypt >= 4.4.27])
 PKG_CHECK_MODULES([glib],    [glib-2.0 >= 2.50 gio-2.0 gio-unix-2.0])
 PKG_CHECK_MODULES([jansson], [jansson >= 2.0.0])
 PKG_CHECK_MODULES([libite],  [libite >= 2.6.1])
-PKG_CHECK_MODULES([sysrepo], [sysrepo >= 2.2.36])
+PKG_CHECK_MODULES([sysrepo], [sysrepo >= 4.2.10])
+PKG_CHECK_MODULES([libyang], [libyang >= 4.2.2])
 PKG_CHECK_MODULES([libsrx],  [libsrx >= 1.0.0])
 
 # Control build with automake flags

src/confd/src/Makefile.am

@@ -1,8 +1,15 @@
 AM_CPPFLAGS             = -D_DEFAULT_SOURCE -D_XOPEN_SOURCE -D_GNU_SOURCE -DYANG_PATH_=\"$(YANGDIR)\"
+AM_CPPFLAGS            +=  -DCONFD_VERSION=\"$(PACKAGE_VERSION)\"
 CLEANFILES              = $(rauc_installer_sources)
 plugindir               = $(srpdplugindir)
 plugin_LTLIBRARIES      = confd-plugin.la
 
+sbin_PROGRAMS           = confd
+
+confd_CFLAGS            = $(sysrepo_CFLAGS) $(libyang_CFLAGS) $(jansson_CFLAGS) $(libite_CFLAGS)
+confd_LDADD             = $(sysrepo_LIBS)   $(libyang_LIBS)   $(jansson_LIBS)   $(libite_LIBS)   -ldl
+confd_SOURCES           = main.c
+
 confd_plugin_la_LDFLAGS = -module -avoid-version -shared
 
 confd_plugin_la_CFLAGS  =			\

src/confd/src/main.c

@@ -0,0 +1,840 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * confd - Infix configuration daemon
+ *
+ * Replaces sysrepo-plugind + bootstrap + load with a single binary.
+ * One sr_connect(), all datastore operations in-process, then load
+ * plugins and enter the event loop.
+ *
+ * Copyright (c) 2018 - 2021 Deutsche Telekom AG.
+ * Copyright (c) 2018 - 2021 CESNET, z.s.p.o.
+ */
+
+#include <dirent.h>
+#include <dlfcn.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <glob.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <jansson.h>
+#include <libyang/libyang.h>
+#include <libite/lite.h>
+#include <sysrepo.h>
+#include <sysrepo/version.h>
+
+/* Callback type names from sysrepo plugin API */
+#define SRP_INIT_CB    "sr_plugin_init_cb"
+#define SRP_CLEANUP_CB "sr_plugin_cleanup_cb"
+
+#ifndef CONFD_VERSION
+#define CONFD_VERSION PACKAGE_VERSION
+#endif
+
+#ifndef SRPD_PLUGINS_PATH
+#define SRPD_PLUGINS_PATH "/usr/lib/sysrepo-plugind/plugins"
+#endif
+
+struct plugin {
+	void *handle;
+	char *name;
+	int (*init_cb)(sr_session_ctx_t *session, void **private_data);
+	void (*cleanup_cb)(sr_session_ctx_t *session, void *private_data);
+	void *private_data;
+	int initialized;
+};
+
+/* Protected flag for terminating */
+static int loop_finish;
+static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+
+static void error_print(int sr_error, const char *format, ...)
+{
+	va_list ap;
+	char msg[2048];
+
+	if (!sr_error)
+		snprintf(msg, sizeof(msg), "confd error: %s\n", format);
+	else
+		snprintf(msg, sizeof(msg), "confd error: %s (%s)\n", format, sr_strerror(sr_error));
+
+	va_start(ap, format);
+	vfprintf(stderr, msg, ap);
+	va_end(ap);
+}
+
+static void version_print(void)
+{
+	printf("confd - Infix configuration daemon v%s, compiled with libsysrepo v%s\n\n",
+	       CONFD_VERSION, SR_VERSION);
+}
+
+static void help_print(void)
+{
+	printf(
+		"Usage:\n"
+		"  confd [-h] [-V] [-v <level>] [-d] [-n] [-f] [-p pidfile]\n"
+		"        [-F factory-config] [-S startup-config] [-E failure-config]\n"
+		"        [-t timeout]\n"
+		"\n"
+		"Options:\n"
+		"  -h, --help           Prints usage help.\n"
+		"  -V, --version        Prints version information.\n"
+		"  -v, --verbosity <level>\n"
+		"                       Change verbosity to a level (none, error, warning, info, debug) or\n"
+		"                       number (0, 1, 2, 3, 4).\n"
+		"  -d, --debug          Debug mode - not daemonized and logs to stderr.\n"
+		"  -n, --foreground     Run in foreground and log to syslog.\n"
+		"  -f, --fatal-plugin-fail\n"
+		"                       Terminate if any plugin initialization fails.\n"
+		"  -p, --pid-file <path>\n"
+		"                       Create a PID file at the specified path.\n"
+		"  -F, --factory-config <path>\n"
+		"                       Factory default config file (default: /etc/factory-config.cfg).\n"
+		"  -S, --startup-config <path>\n"
+		"                       Startup config file (default: /cfg/startup-config.cfg).\n"
+		"  -E, --failure-config <path>\n"
+		"                       Failure fallback config file (default: /etc/failure-config.cfg).\n"
+		"  -t, --timeout <ms>   Sysrepo operation timeout in seconds (default: 60).\n"
+		"\n"
+		"Environment variable $SRPD_PLUGINS_PATH overwrites the default plugins directory.\n"
+		"\n");
+}
+
+static void signal_handler(int sig)
+{
+	switch (sig) {
+	case SIGINT:
+	case SIGQUIT:
+	case SIGABRT:
+	case SIGTERM:
+	case SIGHUP:
+		pthread_mutex_lock(&lock);
+		if (!loop_finish) {
+			loop_finish = 1;
+			pthread_cond_signal(&cond);
+		} else {
+			error_print(0, "Exiting without a proper cleanup");
+			exit(EXIT_FAILURE);
+		}
+		pthread_mutex_unlock(&lock);
+		break;
+	default:
+		error_print(0, "Exiting on receiving an unhandled signal");
+		exit(EXIT_FAILURE);
+	}
+}
+
+static void handle_signals(void)
+{
+	struct sigaction action;
+	sigset_t block_mask;
+
+	sigfillset(&block_mask);
+	action.sa_handler = signal_handler;
+	action.sa_mask = block_mask;
+	action.sa_flags = 0;
+	sigaction(SIGINT, &action, NULL);
+	sigaction(SIGQUIT, &action, NULL);
+	sigaction(SIGABRT, &action, NULL);
+	sigaction(SIGTERM, &action, NULL);
+	sigaction(SIGHUP, &action, NULL);
+
+	action.sa_handler = SIG_IGN;
+	sigaction(SIGPIPE, &action, NULL);
+	sigaction(SIGTSTP, &action, NULL);
+	sigaction(SIGTTIN, &action, NULL);
+	sigaction(SIGTTOU, &action, NULL);
+}
+
+static void daemon_init(int debug, sr_log_level_t log_level)
+{
+	pid_t pid = 0, sid = 0;
+	int fd = -1;
+
+	if (debug) {
+		handle_signals();
+		if (debug < 0)
+			goto done;
+		sr_log_stderr(log_level);
+		return;
+	}
+
+	pid = fork();
+	if (pid < 0) {
+		error_print(0, "fork() failed (%s).", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+	if (pid > 0)
+		exit(EXIT_SUCCESS);
+
+	handle_signals();
+
+	sid = setsid();
+	if (sid < 0) {
+		error_print(0, "setsid() failed (%s).", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	if (chdir("/") < 0) {
+		error_print(0, "chdir() failed (%s).", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	fd = open("/dev/null", O_RDWR, 0);
+	if (fd != -1) {
+		dup2(fd, STDIN_FILENO);
+		dup2(fd, STDOUT_FILENO);
+		dup2(fd, STDERR_FILENO);
+		close(fd);
+	}
+
+done:
+	sr_log_syslog("confd", log_level);
+}
+
+static int open_pidfile(const char *pidfile)
+{
+	int pidfd;
+
+	pidfd = open(pidfile, O_RDWR | O_CREAT, 0640);
+	if (pidfd < 0) {
+		error_print(0, "Unable to open the PID file \"%s\" (%s).", pidfile, strerror(errno));
+		return -1;
+	}
+
+	if (lockf(pidfd, F_TLOCK, 0) < 0) {
+		if (errno == EACCES || errno == EAGAIN)
+			error_print(0, "Another instance of confd is running.");
+		else
+			error_print(0, "Unable to lock the PID file \"%s\" (%s).", pidfile, strerror(errno));
+		close(pidfd);
+		return -1;
+	}
+
+	return pidfd;
+}
+
+static int write_pidfile(int pidfd)
+{
+	char pid[30] = {0};
+	int pid_len;
+
+	if (ftruncate(pidfd, 0)) {
+		error_print(0, "Failed to truncate pid file (%s).", strerror(errno));
+		return -1;
+	}
+
+	snprintf(pid, sizeof(pid) - 1, "%ld\n", (long)getpid());
+	pid_len = strlen(pid);
+	if (write(pidfd, pid, pid_len) < pid_len) {
+		error_print(0, "Failed to write PID into pid file (%s).", strerror(errno));
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Plugin loading -- external .so files only (no internal plugins)
+ */
+static size_t path_len_no_ext(const char *path)
+{
+	const char *dot;
+
+	dot = strrchr(path, '.');
+	if (!dot || dot == path)
+		return 0;
+
+	return dot - path;
+}
+
+static int load_plugins(struct plugin **plugins, int *plugin_count)
+{
+	void *mem, *handle;
+	struct plugin *plugin;
+	DIR *dir;
+	struct dirent *ent;
+	const char *plugins_dir;
+	char *path;
+	size_t name_len;
+	int rc = 0;
+
+	*plugins = NULL;
+	*plugin_count = 0;
+
+	plugins_dir = getenv("SRPD_PLUGINS_PATH");
+	if (!plugins_dir)
+		plugins_dir = SRPD_PLUGINS_PATH;
+
+	dir = opendir(plugins_dir);
+	if (!dir) {
+		error_print(0, "Opening \"%s\" directory failed (%s).", plugins_dir, strerror(errno));
+		return -1;
+	}
+
+	while ((ent = readdir(dir))) {
+		if (!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, ".."))
+			continue;
+
+		if (asprintf(&path, "%s/%s", plugins_dir, ent->d_name) == -1) {
+			error_print(0, "asprintf() failed (%s).", strerror(errno));
+			rc = -1;
+			break;
+		}
+		handle = dlopen(path, RTLD_LAZY);
+		if (!handle) {
+			error_print(0, "Opening plugin \"%s\" failed (%s).", path, dlerror());
+			free(path);
+			rc = -1;
+			break;
+		}
+		free(path);
+
+		mem = realloc(*plugins, (*plugin_count + 1) * sizeof(**plugins));
+		if (!mem) {
+			error_print(0, "realloc() failed (%s).", strerror(errno));
+			dlclose(handle);
+			rc = -1;
+			break;
+		}
+		*plugins = mem;
+		plugin = &(*plugins)[*plugin_count];
+		memset(plugin, 0, sizeof(*plugin));
+
+		*(void **)&plugin->init_cb = dlsym(handle, SRP_INIT_CB);
+		if (!plugin->init_cb) {
+			error_print(0, "Failed to find function \"%s\" in plugin \"%s\".",
+				    SRP_INIT_CB, ent->d_name);
+			dlclose(handle);
+			rc = -1;
+			break;
+		}
+
+		*(void **)&plugin->cleanup_cb = dlsym(handle, SRP_CLEANUP_CB);
+		if (!plugin->cleanup_cb) {
+			error_print(0, "Failed to find function \"%s\" in plugin \"%s\".",
+				    SRP_CLEANUP_CB, ent->d_name);
+			dlclose(handle);
+			rc = -1;
+			break;
+		}
+
+		plugin->handle = handle;
+
+		name_len = path_len_no_ext(ent->d_name);
+		if (name_len == 0) {
+			error_print(0, "Wrong filename \"%s\".", ent->d_name);
+			dlclose(handle);
+			rc = -1;
+			break;
+		}
+
+		plugin->name = strndup(ent->d_name, name_len);
+		if (!plugin->name) {
+			error_print(0, "strndup() failed.");
+			dlclose(handle);
+			rc = -1;
+			break;
+		}
+
+		++(*plugin_count);
+	}
+
+	closedir(dir);
+	return rc;
+}
+
+/*
+ * Wipe stale sysrepo SHM files for a clean slate every boot.
+ */
+static void wipe_sysrepo_shm(void)
+{
+	glob_t gl;
+
+	if (glob("/dev/shm/sr_*", 0, NULL, &gl) == 0) {
+		for (size_t i = 0; i < gl.gl_pathc; i++)
+			unlink(gl.gl_pathv[i]);
+		globfree(&gl);
+	}
+}
+
+const char *basenm(const char *path)
+{
+	const char *slash;
+
+	if (!path)
+		return NULL;
+
+	slash = strrchr(path, '/');
+	if (slash)
+		return slash[1] ? slash + 1 : NULL;
+
+	return path;
+}
+
+/*
+ * Append error message to login banners.
+ */
+static void banner_append(const char *msg)
+{
+	const char *files[] = {
+		"/etc/banner",
+		"/etc/issue",
+		"/etc/issue.net",
+	};
+
+	for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
+		FILE *fp = fopen(files[i], "a");
+
+		if (fp) {
+			fprintf(fp, "\n%s\n", msg);
+			fclose(fp);
+		}
+	}
+}
+
+/*
+ * Smart migration: only fork+exec the migrate script if the version
+ * in the config file doesn't match the current confd version.
+ */
+static int maybe_migrate(const char *path)
+{
+	const char *backup_dir = "/cfg/backup";
+	json_t *root, *meta, *ver;
+	const char *file_ver;
+	char backup[256];
+	int rc;
+
+	root = json_load_file(path, 0, NULL);
+	if (!root)
+		return -1;
+
+	meta     = json_object_get(root, "infix-meta:meta");
+	ver      = meta ? json_object_get(meta, "version") : NULL;
+	file_ver = ver ? json_string_value(ver) : "0.0";
+
+	if (!strcmp(file_ver, CONFD_VERSION)) {
+		json_decref(root);
+		return 0;
+	}
+	json_decref(root);
+
+	SRPLG_LOG_INF("confd", "%s config version %s vs confd %s, migrating ...",
+		      path, file_ver, CONFD_VERSION);
+
+	mkpath(backup_dir, 0770);
+	chown(backup_dir, 0, 10); /* root:wheel */
+
+	snprintf(backup, sizeof(backup), "%s/%s", backup_dir, basenm(path));
+	rc = systemf("migrate -i -b \"%s\" \"%s\"", backup, path);
+	if (rc)
+		SRPLG_LOG_ERR("confd", "Migration of %s failed (rc=%d)", path, rc);
+
+	return rc;
+}
+
+static int file_exists(const char *path)
+{
+	return access(path, F_OK) == 0;
+}
+
+/*
+ * Load a JSON config file into the running datastore.
+ * Mirrors what sysrepocfg -I does: lyd_parse_data() + sr_replace_config().
+ */
+static int load_config(sr_conn_ctx_t *conn, sr_session_ctx_t *sess,
+		       const char *path, uint32_t timeout_ms)
+{
+	const struct ly_ctx *ly_ctx;
+	struct lyd_node *data = NULL;
+	struct ly_in *in = NULL;
+	LY_ERR lyrc;
+	int r;
+
+	ly_ctx = sr_acquire_context(conn);
+
+	lyrc = ly_in_new_filepath(path, 0, &in);
+	if (lyrc == LY_EINVAL) {
+		/* empty file */
+		char *empty = strdup("");
+
+		ly_in_new_memory(empty, &in);
+	} else if (lyrc) {
+		error_print(0, "Failed to open \"%s\" for reading", path);
+		sr_release_context(conn);
+		return -1;
+	}
+
+	lyrc = lyd_parse_data(ly_ctx, NULL, in, LYD_JSON,
+			      LYD_PARSE_NO_STATE | LYD_PARSE_ONLY | LYD_PARSE_STRICT,
+			      0, &data);
+	ly_in_free(in, 1);
+
+	if (lyrc) {
+		SRPLG_LOG_ERR("confd", "Parsing %s failed", path);
+		sr_release_context(conn);
+		return -1;
+	}
+
+	sr_release_context(conn);
+
+	r = sr_replace_config(sess, NULL, data, timeout_ms);
+	if (r != SR_ERR_OK) {
+		SRPLG_LOG_ERR("confd", "sr_replace_config failed: %s", sr_strerror(r));
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Export running datastore to a JSON file.
+ */
+static int export_running(sr_session_ctx_t *sess, const char *path, uint32_t timeout_ms)
+{
+	sr_data_t *data = NULL;
+	FILE *fp;
+	int r;
+
+	r = sr_get_data(sess, "/*", 0, timeout_ms, 0, &data);
+	if (r != SR_ERR_OK) {
+		SRPLG_LOG_ERR("confd", "sr_get_data failed: %s", sr_strerror(r));
+		return -1;
+	}
+
+	fp = fopen(path, "w");
+	if (!fp) {
+		SRPLG_LOG_ERR("confd", "Failed to open %s for writing: %s", path, strerror(errno));
+		sr_release_data(data);
+		return -1;
+	}
+
+	lyd_print_file(fp, data ? data->tree : NULL, LYD_JSON, LYD_PRINT_SIBLINGS);
+	fclose(fp);
+	sr_release_data(data);
+
+	chown(path, 0, 0);    /* root:root initially */
+	chmod(path, 0660);
+
+	/* Set group to 'wheel' for admin access */
+	systemf("chgrp wheel '%s' 2>/dev/null", path);
+
+	return 0;
+}
+
+/*
+ * Handle startup-config load failure: revert to factory-default,
+ * then load failure-config, set error banners.
+ */
+static void handle_startup_failure(sr_session_ctx_t *sess, const char *failure_path,
+				   sr_conn_ctx_t *conn, uint32_t timeout_ms)
+{
+	int r;
+
+	SRPLG_LOG_ERR("confd", "Failed loading startup-config, reverting to Fail Secure mode!");
+
+	/* Reset to factory-default */
+	r = sr_copy_config(sess, NULL, SR_DS_FACTORY_DEFAULT, timeout_ms);
+	if (r != SR_ERR_OK) {
+		SRPLG_LOG_ERR("confd", "sr_copy_config(factory-default) failed: %s", sr_strerror(r));
+		/* Nuclear option: wipe everything */
+		systemf("rm -f /etc/sysrepo/data/*startup* /etc/sysrepo/data/*running* /dev/shm/sr_*");
+		return;
+	}
+
+	/* Load failure-config on top */
+	if (file_exists(failure_path)) {
+		if (load_config(conn, sess, failure_path, timeout_ms)) {
+			SRPLG_LOG_ERR("confd", "Failed loading failure-config, aborting!");
+			banner_append("CRITICAL ERROR: Logins are disabled, no credentials available");
+			systemf("initctl -nbq runlevel 9");
+			return;
+		}
+	}
+
+	banner_append("ERROR: Corrupt startup-config, system has reverted to default login credentials");
+}
+
+/*
+ * Enable test-mode if the test-mode marker exists.
+ */
+static void maybe_enable_test_mode(void)
+{
+	if (file_exists("/mnt/aux/test-mode"))
+		systemf("sysrepoctl -c infix-test -e test-mode-enable");
+}
+
+/*
+ * Determine which config to load:
+ * - test-mode (unless override exists)
+ * - startup-config
+ * - first-boot from factory
+ */
+static int bootstrap_config(sr_conn_ctx_t *conn, sr_session_ctx_t *sess,
+			    const char *factory_path, const char *startup_path,
+			    const char *failure_path, const char *test_path,
+			    uint32_t timeout_ms)
+{
+	const char *config_path;
+	int r;
+
+	/* Test mode support */
+	if (file_exists("/mnt/aux/test-mode")) {
+		if (file_exists("/mnt/aux/test-override-startup")) {
+			unlink("/mnt/aux/test-override-startup");
+			config_path = startup_path;
+		} else {
+			SRPLG_LOG_INF("confd", "Test mode detected, switching to test-config");
+			config_path = test_path;
+		}
+	} else {
+		config_path = startup_path;
+	}
+
+	if (file_exists(config_path)) {
+		/* Run migration if needed */
+		maybe_migrate(config_path);
+
+		/* Load startup (or test) config */
+		SRPLG_LOG_INF("confd", "Loading %s ...", config_path);
+		if (load_config(conn, sess, config_path, timeout_ms)) {
+			handle_startup_failure(sess, failure_path, conn, timeout_ms);
+			return 0; /* continue running even in fail-secure */
+		}
+
+		SRPLG_LOG_INF("confd", "Loaded %s successfully, syncing startup datastore.", config_path);
+		sr_session_switch_ds(sess, SR_DS_STARTUP);
+		r = sr_copy_config(sess, NULL, SR_DS_RUNNING, timeout_ms);
+		sr_session_switch_ds(sess, SR_DS_RUNNING);
+		if (r != SR_ERR_OK)
+			SRPLG_LOG_WRN("confd", "Failed to sync startup datastore: %s", sr_strerror(r));
+
+		return 0;
+	}
+
+	/* First boot: no startup-config, initialize from factory */
+	SRPLG_LOG_INF("confd", "startup-config missing, initializing from factory-config");
+
+	r = sr_copy_config(sess, NULL, SR_DS_FACTORY_DEFAULT, timeout_ms);
+	if (r != SR_ERR_OK) {
+		SRPLG_LOG_ERR("confd", "sr_copy_config(factory-default) failed: %s", sr_strerror(r));
+		return -1;
+	}
+
+	/* Export running → startup file */
+	if (export_running(sess, startup_path, timeout_ms))
+		SRPLG_LOG_WRN("confd", "Failed to export running to %s", startup_path);
+
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	struct plugin *plugins = NULL;
+	sr_conn_ctx_t *conn = NULL;
+	sr_session_ctx_t *sess = NULL;
+	sr_log_level_t log_level = SR_LL_ERR;
+	int plugin_count = 0, i, r, rc = EXIT_FAILURE, opt, debug = 0;
+	int pidfd = -1, fatal_fail = 0;
+	const char *pidfile = NULL;
+	const char *factory_path = "/etc/factory-config.cfg";
+	const char *startup_path = "/cfg/startup-config.cfg";
+	const char *failure_path = "/etc/failure-config.cfg";
+	const char *test_path = "/etc/test-config.cfg";
+	uint32_t timeout_s = 60;
+	uint32_t timeout_ms;
+
+	struct option options[] = {
+		{"help",              no_argument,       NULL, 'h'},
+		{"version",           no_argument,       NULL, 'V'},
+		{"verbosity",         required_argument, NULL, 'v'},
+		{"debug",             no_argument,       NULL, 'd'},
+		{"foreground",        no_argument,       NULL, 'n'},
+		{"pid-file",          required_argument, NULL, 'p'},
+		{"fatal-plugin-fail", no_argument,       NULL, 'f'},
+		{"factory-config",    required_argument, NULL, 'F'},
+		{"startup-config",    required_argument, NULL, 'S'},
+		{"failure-config",    required_argument, NULL, 'E'},
+		{"timeout",           required_argument, NULL, 't'},
+		{NULL,                0,                 NULL, 0},
+	};
+
+	opterr = 0;
+	while ((opt = getopt_long(argc, argv, "hVv:dnp:fF:S:E:t:", options, NULL)) != -1) {
+		switch (opt) {
+		case 'h':
+			version_print();
+			help_print();
+			rc = EXIT_SUCCESS;
+			goto cleanup;
+		case 'V':
+			version_print();
+			rc = EXIT_SUCCESS;
+			goto cleanup;
+		case 'v':
+			if (!strcmp(optarg, "none"))
+				log_level = SR_LL_NONE;
+			else if (!strcmp(optarg, "error"))
+				log_level = SR_LL_ERR;
+			else if (!strcmp(optarg, "warning"))
+				log_level = SR_LL_WRN;
+			else if (!strcmp(optarg, "info"))
+				log_level = SR_LL_INF;
+			else if (!strcmp(optarg, "debug"))
+				log_level = SR_LL_DBG;
+			else if (strlen(optarg) == 1 && optarg[0] >= '0' && optarg[0] <= '4')
+				log_level = atoi(optarg);
+			else {
+				error_print(0, "Invalid verbosity \"%s\"", optarg);
+				goto cleanup;
+			}
+			break;
+		case 'd':
+			debug = 1;
+			break;
+		case 'n':
+			debug = -1;
+			break;
+		case 'p':
+			pidfile = optarg;
+			break;
+		case 'f':
+			fatal_fail = 1;
+			break;
+		case 'F':
+			factory_path = optarg;
+			break;
+		case 'S':
+			startup_path = optarg;
+			break;
+		case 'E':
+			failure_path = optarg;
+			break;
+		case 't':
+			timeout_s = (uint32_t)atoi(optarg);
+			break;
+		default:
+			error_print(0, "Invalid option or missing argument: -%c", optopt);
+			goto cleanup;
+		}
+	}
+
+	if (optind < argc) {
+		error_print(0, "Redundant parameters");
+		goto cleanup;
+	}
+
+	timeout_ms = timeout_s * 1000;
+
+	if (pidfile && (pidfd = open_pidfile(pidfile)) < 0)
+		goto cleanup;
+
+	/* Load plugins from disk (dlopen) before daemonizing */
+	if (load_plugins(&plugins, &plugin_count))
+		error_print(0, "load_plugins failed (continuing)");
+
+	/* Daemonize -- after this point, confd no longer logs to stderr */
+	daemon_init(debug, log_level);
+
+	/* Phase 1: Wipe stale SHM for a clean slate */
+	wipe_sysrepo_shm();
+
+	/* Phase 2: Connect to sysrepo (rebuilds SHM from installed YANG modules) */
+	r = sr_connect(0, &conn);
+	if (r != SR_ERR_OK) {
+		error_print(r, "Failed to connect");
+		goto cleanup;
+	}
+
+	/* Phase 3: Install factory defaults into all datastores */
+	SRPLG_LOG_INF("confd", "Loading factory-default datastore from %s ...", factory_path);
+	r = sr_install_factory_config(conn, factory_path);
+	if (r != SR_ERR_OK) {
+		SRPLG_LOG_ERR("confd", "sr_install_factory_config failed: %s", sr_strerror(r));
+		goto cleanup;
+	}
+
+	/* Phase 4: Start running-datastore session */
+	r = sr_session_start(conn, SR_DS_RUNNING, &sess);
+	if (r != SR_ERR_OK) {
+		error_print(r, "Failed to start new session");
+		goto cleanup;
+	}
+
+	/* Phase 4b: Clear running datastore so plugin init sees an empty
+	 * tree.  This matches the original bootstrap flow where running
+	 * was cleared with '{}' before sysrepo-plugind started.  When we
+	 * later load startup-config, the diff will be all-create which is
+	 * what the plugin callbacks expect. */
+	r = sr_replace_config(sess, NULL, NULL, timeout_ms);
+	if (r != SR_ERR_OK) {
+		SRPLG_LOG_ERR("confd", "Failed to clear running datastore: %s", sr_strerror(r));
+		goto cleanup;
+	}
+
+	/* Enable test-mode YANG feature if needed */
+	maybe_enable_test_mode();
+
+	/* Phase 5: Initialize plugins (subscribe to YANG module changes) */
+	for (i = 0; i < plugin_count; i++) {
+		r = plugins[i].init_cb(sess, &plugins[i].private_data);
+		if (r) {
+			SRPLG_LOG_ERR("confd", "Plugin \"%s\" initialization failed (%s).",
+				      plugins[i].name, sr_strerror(r));
+			if (fatal_fail)
+				goto cleanup;
+		} else {
+			SRPLG_LOG_INF("confd", "Plugin \"%s\" initialized.", plugins[i].name);
+			plugins[i].initialized = 1;
+		}
+	}
+
+	/* Phase 6: Load startup config -- plugins are now subscribed, so
+	 * sr_replace_config() will trigger their change callbacks. */
+	if (bootstrap_config(conn, sess, factory_path, startup_path,
+			     failure_path, test_path, timeout_ms))
+		goto cleanup;
+
+	/* Write PID file after everything is ready */
+	if (pidfile && write_pidfile(pidfd) < 0)
+		goto cleanup;
+
+	/* Wait for a terminating signal */
+	pthread_mutex_lock(&lock);
+	while (!loop_finish)
+		pthread_cond_wait(&cond, &lock);
+	pthread_mutex_unlock(&lock);
+
+	rc = EXIT_SUCCESS;
+
+cleanup:
+	while (plugin_count > 0) {
+		if (plugins[plugin_count - 1].initialized)
+			plugins[plugin_count - 1].cleanup_cb(sess, plugins[plugin_count - 1].private_data);
+		if (plugins[plugin_count - 1].handle)
+			dlclose(plugins[plugin_count - 1].handle);
+		free(plugins[plugin_count - 1].name);
+		--plugin_count;
+	}
+	free(plugins);
+
+	if (pidfd >= 0) {
+		close(pidfd);
+		unlink(pidfile);
+	}
+
+	sr_disconnect(conn);
+	return rc;
+}