control: remove unprivileged socket

compat/getpeereid.c

@@ -0,0 +1,64 @@
+/*
+ * compat: getpeereid
+ * SPDX-License-Identifier: BSD-2-Clause
+ * Copyright (c) 2006-2026 Roy Marples <roy@marples.name>
+ * All rights reserved
+
+ * 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 <sys/types.h>
+#include <sys/socket.h>
+
+#ifdef __sun
+#include <ucred.h>
+#endif
+
+#include "getpeereid.h"
+
+int
+getpeereid(int fd, uid_t *uid, gid_t *gid)
+{
+#if defined(SO_PEERCRED)
+	struct ucred creds;
+	socklen_t creds_len = sizeof(creds);
+
+	if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &creds, &creds_len) == -1)
+		return -1;
+
+	*uid = creds.uid;
+	*gid = creds.gid;
+#elif defined(__sun)
+	ucred_t *ucred = NULL;
+
+	if (getpeerucred(fd, &ucred) == -1)
+		return -1;
+
+	*uid = ucred_geteuid(ucred);
+	*gid = ucred_getegid(ucred);
+	ucred_free(ucred);
+#else
+#error OS has no getpeereid support!
+#endif
+
+	return 0;
+}

compat/getpeereid.h

@@ -0,0 +1,36 @@
+/*
+ * compat: getpeereid
+ * SPDX-License-Identifier: BSD-2-Clause
+ * Copyright (c) 2006-2026 Roy Marples <roy@marples.name>
+ * All rights reserved
+
+ * 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.
+ */
+
+#ifndef GETPEEREID_H
+#define GETPEEREID_H
+
+#include <sys/types.h>
+
+int getpeereid(int, uid_t *, gid_t *);
+
+#endif

configure

@@ -938,6 +938,29 @@ if [ "$ARC4RANDOM_UNIFORM" = no ]; then
 	echo "#include			\"compat/arc4random_uniform.h\"" >>$CONFIG_H
 fi
 
+if [ -z "$GETPEEREID" ]; then
+	printf "Testing for getpeereid ... "
+	cat <<EOF >_getpeereid.c
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+int main(void) {
+	return getpeereid(0, NULL, NULL);
+}
+EOF
+	if $XCC _getpeereid.c -o _getpeereid 2>&3; then
+		GETPEEREID=yes
+	else
+		GETPEEREID=no
+	fi
+	echo "$GETPEEREID"
+	rm -rf _getpeereid.* _getpeereid
+fi
+if [ "$GETPEEREID" = no ]; then
+	echo "COMPAT_SRCS+=	compat/getpeereid.c" >>$CONFIG_MK
+	echo "#include			\"compat/getpeereid.h\"" >>$CONFIG_H
+fi
+
 if [ -z "$MEMSET_EXPLICIT" ]; then
 	printf "Testing for memset_explicit ... "
 	cat <<EOF >_memset_explicit.c