diff --git a/usr.sbin/syslogd/Makefile b/usr.sbin/syslogd/Makefile
--- a/usr.sbin/syslogd/Makefile
+++ b/usr.sbin/syslogd/Makefile
@@ -17,7 +17,8 @@
 LIBADD=	util
 
 .if ${MK_CASPER} != "no"
-SRCS+=	syslogd_cap.c
+SRCS+=	syslogd_cap.c \
+	syslogd_cap_config.c
 CFLAGS+= -DWITH_CASPER
 LIBADD+= cap_net casper nv
 .endif
diff --git a/usr.sbin/syslogd/syslogd.h b/usr.sbin/syslogd/syslogd.h
--- a/usr.sbin/syslogd/syslogd.h
+++ b/usr.sbin/syslogd/syslogd.h
@@ -71,6 +71,8 @@
 #include <sys/syslog.h>
 
 #include <regex.h>
+#include <stdbool.h>
+#include <stdio.h>
 
 #define	MAXLINE		8192		/* maximum line length */
 #define	MAXSVLINE	MAXLINE		/* maximum saved line length */
@@ -178,5 +180,11 @@
 	u_int	f_repeatcount;			/* number of "repeated" msgs */
 	STAILQ_ENTRY(filed) next;		/* next in linked list */
 };
+extern STAILQ_HEAD(filed_list, filed) fhead;
+
+extern char LocalHostName[MAXHOSTNAMELEN];
+
+void closelogfiles(void);
+void parseconfigfile(FILE *, bool);
 
 #endif /* !_SYSLOGD_H_ */
diff --git a/usr.sbin/syslogd/syslogd.c b/usr.sbin/syslogd/syslogd.c
--- a/usr.sbin/syslogd/syslogd.c
+++ b/usr.sbin/syslogd/syslogd.c
@@ -198,8 +198,10 @@
 #define	RFC3164_DATELEN	15
 #define	RFC3164_DATEFMT	"%b %e %H:%M:%S"
 
-static STAILQ_HEAD(, filed) fhead =
-    STAILQ_HEAD_INITIALIZER(fhead);	/* Log files that we write to */
+/*
+ * List of log files.
+ */
+struct filed_list fhead = STAILQ_HEAD_INITIALIZER(fhead);
 static struct filed consfile;		/* Console */
 
 /*
@@ -279,7 +281,7 @@
 static bool	Debug;		/* debug flag */
 static bool	Foreground = false; /* Run in foreground, instead of daemonizing */
 static bool	resolve = true;	/* resolve hostname */
-static char	LocalHostName[MAXHOSTNAMELEN];	/* our hostname */
+char		LocalHostName[MAXHOSTNAMELEN];	/* our hostname */
 static const char *LocalDomain;	/* our local domain name */
 static bool	Initialized;	/* set when we have initialized ourselves */
 static int	MarkInterval = 20 * 60;	/* interval between marks in seconds */
@@ -2226,7 +2228,7 @@
 	return (1);
 }
 
-static void
+void
 parseconfigfile(FILE *cf, bool allow_includes)
 {
 	FILE *cf2;
@@ -2379,7 +2381,7 @@
 /*
  * Close all open log files.
  */
-static void
+void
 closelogfiles(void)
 {
 	struct filed *f;
diff --git a/usr.sbin/syslogd/syslogd_cap.h b/usr.sbin/syslogd/syslogd_cap.h
--- a/usr.sbin/syslogd/syslogd_cap.h
+++ b/usr.sbin/syslogd/syslogd_cap.h
@@ -43,9 +43,17 @@
 
 #include "syslogd.h"
 
+void cap_readconfigfile(cap_channel_t *, const char *);
+int casper_readconfigfile(nvlist_t *, nvlist_t *);
+
 nvlist_t *filed_to_nvlist(const struct filed *);
 struct filed *nvlist_to_filed(const nvlist_t *);
 
+#else /* !WITH_CASPER */
+
+#define	cap_readconfigfile(chan, cf) \
+	readconfigfile(cf)
+
 #endif /* WITH_CASPER */
 
 #endif /* !_SYSLOGD_CAP_H_ */
diff --git a/usr.sbin/syslogd/syslogd_cap.c b/usr.sbin/syslogd/syslogd_cap.c
--- a/usr.sbin/syslogd/syslogd_cap.c
+++ b/usr.sbin/syslogd/syslogd_cap.c
@@ -198,10 +198,14 @@
 
 /* This is where libcasper receives commands via nvlist. */
 static int
-casper_command(const char *cmd __unused, const nvlist_t *limits __unused,
-    nvlist_t *nvlin __unused, nvlist_t *nvlout __unused)
+casper_command(const char *cmd, const nvlist_t *limits __unused,
+    nvlist_t *nvlin, nvlist_t *nvlout)
 {
 	int error = EINVAL;
+
+	if (strcmp(cmd, "readconfigfile") == 0)
+		error = casper_readconfigfile(nvlin, nvlout);
+
 	return (error);
 }
 
diff --git a/usr.sbin/syslogd/syslogd_cap_config.c b/usr.sbin/syslogd/syslogd_cap_config.c
new file mode 100644
--- /dev/null
+++ b/usr.sbin/syslogd/syslogd_cap_config.c
@@ -0,0 +1,139 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2023 The FreeBSD Foundation
+ *
+ * This software was developed by Jake Freeland <jfree@FreeBSD.org>
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <err.h>
+#include <string.h>
+
+#include "syslogd_cap.h"
+
+/*
+ * Return an nvlist "environment" containing global variables
+ * that are subject to change during runtime.
+ */
+static nvlist_t *
+create_cap_env(void)
+{
+	struct filed *f;
+	nvlist_t *env = nvlist_create(0);
+	uint64_t count = 0;
+
+	nvlist_add_string(env, "LocalHostName", LocalHostName);
+	STAILQ_FOREACH(f, &fhead, next) {
+		nvlist_t *nvl_filed = filed_to_nvlist(f);
+		nvlist_append_nvlist_array(env, "filed_list", nvl_filed);
+		nvlist_destroy(nvl_filed);
+		++count;
+	}
+	if (count > 0)
+		nvlist_add_number(env, "filed_count", count);
+
+	return (env);
+}
+
+/*
+ * Populate the program's global variables using the values
+ * stored in the provided nvlist, @env.
+ */
+static void
+populate_cap_env(const nvlist_t *env)
+{
+	if (nvlist_exists_string(env, "LocalHostName")) {
+		strlcpy(LocalHostName, nvlist_get_string(env, "LocalHostName"),
+		    sizeof(LocalHostName));
+	}
+	if (nvlist_exists_nvlist_array(env, "filed_list")) {
+		struct filed *f;
+		const nvlist_t * const *filed_list;
+		uint64_t filed_count, i;
+
+		filed_count = nvlist_get_number(env, "filed_count");
+		filed_list = nvlist_get_nvlist_array(env, "filed_list",
+		    &filed_count);
+		for (i = 0; i < filed_count; ++i) {
+			f = nvlist_to_filed(filed_list[i]);
+			STAILQ_INSERT_TAIL(&fhead, f, next);
+		}
+	}
+}
+
+/*
+ * Parse the configuration and populate our global environment
+ * with the resulting nvlist.
+ */
+void
+cap_readconfigfile(cap_channel_t *chan, const char *path)
+{
+	nvlist_t *nvl = nvlist_create(0);
+	int error;
+
+	nvlist_add_string(nvl, "cmd", "readconfigfile");
+	nvlist_add_string(nvl, "path", path);
+	nvlist_move_nvlist(nvl, "env", create_cap_env());
+	nvl = cap_xfer_nvlist(chan, nvl);
+	if (nvl == NULL)
+		err(1, "Failed to xfer configuration nvlist");
+	error = nvlist_get_number(nvl, "error");
+	if (error != 0) {
+		nvlist_destroy(nvl);
+		errc(1, error, "Failed to parse configuration file: %s", path);
+	}
+	populate_cap_env(nvlist_get_nvlist(nvl, "env"));
+	nvlist_destroy(nvl);
+}
+
+/*
+ * Now that we're executing as libcasper, we can parse the syslogd
+ * configuration. Return our global environment via nvlist.
+ */
+int
+casper_readconfigfile(nvlist_t *nvlin, nvlist_t *nvlout)
+{
+	FILE *cf = fopen(nvlist_get_string(nvlin, "path"), "r");
+	if (cf == NULL)
+		return (errno);
+	populate_cap_env(nvlist_get_nvlist(nvlin, "env"));
+
+	/*
+	 * If we're here, the config has been reset
+	 * and syslogd's global filed list has been
+	 * cleared. Do the same here.
+	 */
+	closelogfiles();
+
+	/*
+	 * Parse the configuration file and create
+	 * a snapshot of our global env for syslogd.
+	 */
+	parseconfigfile(cf, true);
+	nvlist_add_nvlist(nvlout, "env", create_cap_env());
+
+	(void)fclose(cf);
+	return (0);
+}