1 files changed, 223 insertions, 0 deletions

diff --git a/sys/kern/subr_boot.c b/sys/kern/subr_boot.c
new file mode 100644
index 000000000000..00890c3150d7
--- /dev/null
+++ b/sys/kern/subr_boot.c
@@ -0,0 +1,223 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
+ * All Rights Reserved.
+ * Copyright (c) 1998 Robert Nordier
+ * All Rights Reserved.
+ * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
+ * All rights reserved.
+ * Copyright (c) 2014 Roger Pau Monné <roger.pau@citrix.com>
+ * All Rights Reserved.
+ * Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
+ * Copyright (c) 2018 Netflix
+ *
+ * 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
+ *    in this position and unchanged.
+ * 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/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/* Note: This is compiled in both the kernel and boot loader contexts */
+
+#include <sys/param.h>
+#ifdef _KERNEL
+#include <sys/systm.h>
+#else
+#include <stand.h>
+#endif
+#include <sys/reboot.h>
+#include <sys/boot.h>
+
+#ifdef _KERNEL
+#define SETENV(k, v)	kern_setenv(k, v)
+#define GETENV(k)	kern_getenv(k)
+#define FREE(v)		freeenv(v)
+#else	/* Boot loader */
+#define SETENV(k, v)	setenv(k, v, 1)
+#define GETENV(k)	getenv(k)
+#define	FREE(v)
+#endif
+
+static struct
+{
+	const char	*ev;
+	int		mask;
+} howto_names[] = {
+	{ "boot_askname",	RB_ASKNAME},
+	{ "boot_cdrom",		RB_CDROM},
+	{ "boot_ddb",		RB_KDB},
+	{ "boot_dfltroot",	RB_DFLTROOT},
+	{ "boot_gdb",		RB_GDB},
+	{ "boot_multicons",	RB_MULTIPLE},
+	{ "boot_mute",		RB_MUTE},
+	{ "boot_pause",		RB_PAUSE},
+	{ "boot_serial",	RB_SERIAL},
+	{ "boot_single",	RB_SINGLE},
+	{ "boot_verbose",	RB_VERBOSE},
+	{ NULL,	0}
+};
+
+/*
+ * In the boot environment, we often parse a command line and have to throw away
+ * its contents. As we do so, we set environment variables that correspond to
+ * the flags we encounter. Later, to get a howto mask, we grovel through these
+ * to reconstruct it. This also allows users in their loader.conf to set them
+ * and have the kernel see them.
+ */
+
+/**
+ * @brief convert the env vars in howto_names into a howto mask
+ */
+int
+boot_env_to_howto(void)
+{
+	int i, howto;
+	char *val;
+
+	for (howto = 0, i = 0; howto_names[i].ev != NULL; i++) {
+		val = GETENV(howto_names[i].ev);
+		if (val != NULL && strcasecmp(val, "no") != 0)
+			howto |= howto_names[i].mask;
+		FREE(val);
+	}
+	return (howto);
+}
+
+/**
+ * @brief Set env vars from howto_names based on howto passed in
+ */
+void
+boot_howto_to_env(int howto)
+{
+	int i;
+
+	for (i = 0; howto_names[i].ev != NULL; i++)
+		if (howto & howto_names[i].mask)
+			SETENV(howto_names[i].ev, "YES");
+}
+
+/**
+ * @brief Helper routine to parse a single arg and return its mask
+ *
+ * Parse all the - options to create a mask (or a serial speed in the
+ * case of -S). If the arg doesn't start with '-' assume it's an env
+ * variable and set that instead.
+ */
+int
+boot_parse_arg(char *v)
+{
+	char *n;
+	int howto;
+
+#if 0
+/* Need to see if this is better or worse than the meat of the #else */
+static const char howto_switches[] = "aCdrgDmphsv";
+static int howto_masks[] = {
+	RB_ASKNAME, RB_CDROM, RB_KDB, RB_DFLTROOT, RB_GDB, RB_MULTIPLE,
+	RB_MUTE, RB_PAUSE, RB_SERIAL, RB_SINGLE, RB_VERBOSE
+};
+
+	opts = strchr(kargs, '-');
+	while (opts != NULL) {
+		while (*(++opts) != '\0') {
+			sw = strchr(howto_switches, *opts);
+			if (sw == NULL)
+				break;
+			howto |= howto_masks[sw - howto_switches];
+		}
+		opts = strchr(opts, '-');
+	}
+#else
+	howto = 0;
+	if (*v == '-') {
+		while (*v != '\0') {
+			v++;
+			switch (*v) {
+			case 'a': howto |= RB_ASKNAME; break;
+			case 'C': howto |= RB_CDROM; break;
+			case 'd': howto |= RB_KDB; break;
+			case 'D': howto |= RB_MULTIPLE; break;
+			case 'm': howto |= RB_MUTE; break;
+			case 'g': howto |= RB_GDB; break;
+			case 'h': howto |= RB_SERIAL; break;
+			case 'p': howto |= RB_PAUSE; break;
+			case 'P': howto |= RB_PROBE; break;
+			case 'r': howto |= RB_DFLTROOT; break;
+			case 's': howto |= RB_SINGLE; break;
+			case 'S': SETENV("comconsole_speed", v + 1); v += strlen(v); break;
+			case 'v': howto |= RB_VERBOSE; break;
+			}
+		}
+	} else {
+		n = strsep(&v, "=");
+		if (v == NULL)
+			SETENV(n, "1");
+		else
+			SETENV(n, v);
+	}
+#endif
+	return (howto);
+}
+
+/**
+ * @brief breakup the command line into args, and pass to boot_parse_arg
+ */
+int
+boot_parse_cmdline_delim(char *cmdline, const char *delim)
+{
+	char *v;
+	int howto;
+
+	howto = 0;
+	while ((v = strsep(&cmdline, delim)) != NULL) {
+		if (*v == '\0')
+			continue;
+		howto |= boot_parse_arg(v);
+	}
+	return (howto);
+}
+
+/**
+ * @brief Simplified interface for common 'space separated' args
+ */
+int
+boot_parse_cmdline(char *cmdline)
+{
+
+	return (boot_parse_cmdline_delim(cmdline, " \n"));
+}
+
+/**
+ * @brief Pass a vector of strings to boot_parse_arg
+ */
+int
+boot_parse_args(int argc, char *argv[])
+{
+        int i, howto;
+
+	howto = 0;
+        for (i = 1; i < argc; i++)
+                howto |= boot_parse_arg(argv[i]);
+	return (howto);
+}