freebsd-skq/usr.sbin/efivar/efiutil.c
Warner Losh 66c613905f Tweak output of the loader variable
When the DEVICE_PATH is <= 4 that means it's effectively empty. I have
a laptop that has a BIOS that likes to generate these:

8be4df61-93ca-11d2-aa0d-00e098032b8c-Boot2001
0000: 01 00 00 00 04 00 45 00 46 00 49 00 20 00 55 00
0010: 53 00 42 00 20 00 44 00 65 00 76 00 69 00 63 00
0020: 65 00 00 00 7f ff 04 00 52 43

which now decodes as
8be4df61-93ca-11d2-aa0d-00e098032b8c-Boot2001
* EFI USB Device
Empty path
Option:
0000: 52 43

which matches my hand-decode.

Add an extra newline after Option: to make it look nice.

I suspect that these entries really should be VenHw entries instead,
but my ability to change that is NIL, so cope with them as best we can.

efibootmgr(8)'s output is fine and doesn't need adjusting.
2020-09-25 18:20:41 +00:00

193 lines
4.7 KiB
C

/*-
* Copyright (c) 2017-2019 Netflix, Inc.
*
* 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <ctype.h>
#include <efivar.h>
#include <efivar-dp.h>
#include <err.h>
#include <errno.h>
#include <getopt.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "efiutil.h"
#include "efichar.h"
#include <efivar-dp.h>
/*
* Dump the data as ASCII data, which is a pretty
* printed form
*/
void
asciidump(uint8_t *data, size_t datalen)
{
size_t i;
int len;
len = 0;
for (i = 0; i < datalen; i++) {
if (isprint(data[i])) {
len++;
if (len > 80) {
len = 0;
printf("\n");
}
printf("%c", data[i]);
} else {
len +=3;
if (len > 80) {
len = 0;
printf("\n");
}
printf("%%%02x", data[i]);
}
}
printf("\n");
}
void
utf8dump(uint8_t *data, size_t datalen)
{
char *utf8 = NULL;
efi_char *ucs2;
/*
* NUL terminate the string. Not all strings need it, but some
* do and an extra NUL won't change what's printed.
*/
ucs2 = malloc(datalen + sizeof(efi_char));
memcpy(ucs2, data, datalen);
ucs2[datalen / sizeof(efi_char)] = 0;
ucs2_to_utf8(ucs2, &utf8);
printf("%s\n", utf8);
free(utf8);
free(ucs2);
}
void
hexdump(uint8_t *data, size_t datalen)
{
size_t i;
for (i = 0; i < datalen; i++) {
if (i % 16 == 0) {
if (i != 0)
printf("\n");
printf("%04x: ", (int)i);
}
printf("%02x ", data[i]);
}
printf("\n");
}
void
bindump(uint8_t *data, size_t datalen)
{
write(1, data, datalen);
}
#define LOAD_OPTION_ACTIVE 1
#define SIZE(dp, edp) (size_t)((intptr_t)(void *)edp - (intptr_t)(void *)dp)
void
efi_print_load_option(uint8_t *data, size_t datalen, int Aflag, int bflag, int uflag)
{
char *dev, *relpath, *abspath;
uint8_t *ep = data + datalen;
uint8_t *walker = data;
uint32_t attr;
uint16_t fplen;
efi_char *descr;
efidp dp, edp;
char *str = NULL;
char buf[1024];
int len;
void *opt;
int optlen;
int rv;
if (datalen < sizeof(attr) + sizeof(fplen) + sizeof(efi_char))
return;
// First 4 bytes are attribute flags
attr = le32dec(walker);
walker += sizeof(attr);
// Next two bytes are length of the file paths
fplen = le16dec(walker);
walker += sizeof(fplen);
// Next we have a 0 terminated UCS2 string that we know to be aligned
descr = (efi_char *)(intptr_t)(void *)walker;
len = ucs2len(descr); // XXX need to sanity check that len < (datalen - (ep - walker) / 2)
walker += (len + 1) * sizeof(efi_char);
if (walker > ep)
return;
// Now we have fplen bytes worth of file path stuff
dp = (efidp)walker;
walker += fplen;
if (walker > ep)
return;
edp = (efidp)walker;
// Everything left is the binary option args
opt = walker;
optlen = ep - walker;
// We got to here, everything is good
printf("%c ", attr & LOAD_OPTION_ACTIVE ? '*' : ' ');
ucs2_to_utf8(descr, &str);
printf("%s\n", str);
free(str);
if (fplen <= 4) {
printf("Empty path\n");
} else {
while (dp < edp && SIZE(dp, edp) > sizeof(efidp_header)) {
efidp_format_device_path(buf, sizeof(buf), dp, SIZE(dp, edp));
rv = efivar_device_path_to_unix_path(dp, &dev, &relpath, &abspath);
dp = (efidp)((char *)dp + efidp_size(dp));
printf(" %s\n", buf);
if (rv == 0) {
printf(" %*s:%s\n", len + (int)strlen(dev), dev, relpath);
free(dev);
free(relpath);
free(abspath);
}
}
}
if (optlen == 0)
return;
printf("Option:\n");
if (Aflag)
asciidump(opt, optlen);
else if (bflag)
bindump(opt, optlen);
else if (uflag)
utf8dump(opt, optlen);
else
hexdump(opt, optlen);
}