freebsd-dev/usr.sbin/binmiscctl/binmiscctl.c
Sean Bruno b8fc9a86a8 If no arguments are passed to a subcommand that requires arguments,
error out before we deref a null pointer in the check for max length.

Thanks to otis in IRC for the bug report.

MFC after:	3 days
2015-02-15 23:58:57 +00:00

511 lines
11 KiB
C

/*-
* Copyright (c) 2013 Stacey D. Son
* 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <ctype.h>
#include <errno.h>
#include <getopt.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/imgact_binmisc.h>
#include <sys/linker.h>
#include <sys/sysctl.h>
enum cmd {
CMD_ADD = 0,
CMD_REMOVE,
CMD_DISABLE,
CMD_ENABLE,
CMD_LOOKUP,
CMD_LIST,
};
extern char *__progname;
typedef int (*cmd_func_t)(int argc, char *argv[], ximgact_binmisc_entry_t *xbe);
int add_cmd(int argc, char *argv[], ximgact_binmisc_entry_t *xbe);
int name_cmd(int argc, char *argv[], ximgact_binmisc_entry_t *xbe);
int noname_cmd(int argc, char *argv[], ximgact_binmisc_entry_t *xbe);
static const struct {
const int token;
const char *name;
cmd_func_t func;
const char *desc;
const char *args;
} cmds[] = {
{
CMD_ADD,
"add",
add_cmd,
"Add a new binary image activator (requires 'root' privilege)",
"<name> --interpreter <path_and_arguments> \\\n"
"\t\t--magic <magic_bytes> [--mask <mask_bytes>] \\\n"
"\t\t--size <magic_size> [--offset <magic_offset>] \\\n"
"\t\t[--set-enabled]"
},
{
CMD_REMOVE,
"remove",
name_cmd,
"Remove a binary image activator (requires 'root' privilege)",
"<name>"
},
{
CMD_DISABLE,
"disable",
name_cmd,
"Disable a binary image activator (requires 'root' privilege)",
"<name>"
},
{
CMD_ENABLE,
"enable",
name_cmd,
"Enable a binary image activator (requires 'root' privilege)",
"<name>"
},
{
CMD_LOOKUP,
"lookup",
name_cmd,
"Lookup a binary image activator",
"<name>"
},
{
CMD_LIST,
"list",
noname_cmd,
"List all the binary image activators",
""
},
};
static const struct option
add_opts[] = {
{ "set-enabled", no_argument, NULL, 'e' },
{ "interpreter", required_argument, NULL, 'i' },
{ "mask", required_argument, NULL, 'M' },
{ "magic", required_argument, NULL, 'm' },
{ "offset", required_argument, NULL, 'o' },
{ "size", required_argument, NULL, 's' },
{ NULL, 0, NULL, 0 }
};
static char const *cmd_sysctl_name[] = {
IBE_SYSCTL_NAME_ADD,
IBE_SYSCTL_NAME_REMOVE,
IBE_SYSCTL_NAME_DISABLE,
IBE_SYSCTL_NAME_ENABLE,
IBE_SYSCTL_NAME_LOOKUP,
IBE_SYSCTL_NAME_LIST
};
static void
usage(const char *format, ...)
{
va_list args;
size_t i;
int error = 0;
va_start(args, format);
if (format) {
vfprintf(stderr, format, args);
error = -1;
}
va_end(args);
fprintf(stderr, "\n");
fprintf(stderr, "usage: %s command [args...]\n\n", __progname);
for(i = 0; i < ( sizeof (cmds) / sizeof (cmds[0])); i++) {
fprintf(stderr, "%s:\n", cmds[i].desc);
fprintf(stderr, "\t%s %s %s\n\n", __progname, cmds[i].name,
cmds[i].args);
}
exit (error);
}
static void
fatal(const char *format, ...)
{
va_list args;
va_start(args, format);
if (format)
vfprintf(stderr, format, args);
fprintf(stderr, "\n");
exit(-1);
}
static void
getoptstr(char *str, size_t size, const char *argname)
{
if (strlen(optarg) > size)
usage("'%s' too large", argname);
strlcpy(str, optarg, size);
}
static void
printxbe(ximgact_binmisc_entry_t *xbe)
{
uint32_t i, flags = xbe->xbe_flags;
if (xbe->xbe_version != IBE_VERSION) {
fprintf(stderr, "Error: XBE version mismatch\n");
return;
}
printf("name: %s\n", xbe->xbe_name);
printf("interpreter: %s\n", xbe->xbe_interpreter);
printf("flags: %s%s\n", (flags & IBF_ENABLED) ? "ENABLED " : "",
(flags & IBF_USE_MASK) ? "USE_MASK " : "");
printf("magic size: %u\n", xbe->xbe_msize);
printf("magic offset: %u\n", xbe->xbe_moffset);
printf("magic: ");
for(i = 0; i < xbe->xbe_msize; i++) {
if (i && !(i % 12))
printf("\n ");
else
if (i && !(i % 4))
printf(" ");
printf("0x%02x ", xbe->xbe_magic[i]);
}
printf("\n");
if (flags & IBF_USE_MASK) {
printf("mask: ");
for(i = 0; i < xbe->xbe_msize; i++) {
if (i && !(i % 12))
printf("\n ");
else
if (i && !(i % 4))
printf(" ");
printf("0x%02x ", xbe->xbe_mask[i]);
}
printf("\n");
}
printf("\n");
}
static int
demux_cmd(__unused int argc, char *const argv[])
{
size_t i;
optind = 1;
optreset = 1;
for(i = 0; i < ( sizeof (cmds) / sizeof (cmds[0])); i++) {
if (!strcasecmp(cmds[i].name, argv[0])) {
return (i);
}
}
/* Unknown command */
return (-1);
}
static int
strlit2bin_cpy(uint8_t *d, char *s, size_t size)
{
int c;
size_t cnt = 0;
while((c = *s++) != '\0') {
if (c == '\\') {
/* Do '\' escapes. */
switch (*s) {
case '\\':
*d++ = '\\';
break;
case 'x':
s++;
c = toupper(*s++);
*d = (c - (isdigit(c) ? '0' : ('A' - 10))) << 4;
c = toupper(*s++);
*d++ |= c - (isdigit(c) ? '0' : ('A' - 10));
break;
default:
return (-1);
}
} else
*d++ = c;
if (++cnt > size)
return (-1);
}
return (cnt);
}
int
add_cmd(__unused int argc, char *argv[], ximgact_binmisc_entry_t *xbe)
{
int ch;
char *magic = NULL, *mask = NULL;
int sz;
if (strlen(argv[0]) > IBE_NAME_MAX)
usage("'%s' string length longer than IBE_NAME_MAX (%d)",
IBE_NAME_MAX);
strlcpy(&xbe->xbe_name[0], argv[0], IBE_NAME_MAX);
while ((ch = getopt_long(argc, argv, "ei:m:M:o:s:", add_opts, NULL))
!= -1) {
switch(ch) {
case 'i':
getoptstr(xbe->xbe_interpreter, IBE_INTERP_LEN_MAX,
"interpreter");
break;
case 'm':
magic = strdup(optarg);
break;
case 'M':
mask = strdup(optarg);
xbe->xbe_flags |= IBF_USE_MASK;
break;
case 'e':
xbe->xbe_flags |= IBF_ENABLED;
break;
case 'o':
xbe->xbe_moffset = atol(optarg);
break;
case 's':
xbe->xbe_msize = atol(optarg);
if (xbe->xbe_msize == 0 ||
xbe->xbe_msize > IBE_MAGIC_MAX)
usage("Error: Not valid '--size' value. "
"(Must be > 0 and < %u.)\n",
xbe->xbe_msize);
break;
default:
usage("Unknown argument: '%c'", ch);
}
}
if (xbe->xbe_msize == 0) {
if (NULL != magic)
free(magic);
if (NULL != mask)
free(mask);
usage("Error: Missing '--size' argument");
}
if (NULL != magic) {
if (xbe->xbe_msize == 0) {
if (magic)
free(magic);
if (mask)
free(mask);
usage("Error: Missing magic size argument");
}
sz = strlit2bin_cpy(xbe->xbe_magic, magic, IBE_MAGIC_MAX);
free(magic);
if (sz == -1 || (uint32_t)sz != xbe->xbe_msize) {
if (mask)
free(mask);
usage("Error: invalid magic argument");
}
if (mask) {
sz = strlit2bin_cpy(xbe->xbe_mask, mask, IBE_MAGIC_MAX);
free(mask);
if (sz == -1 || (uint32_t)sz != xbe->xbe_msize)
usage("Error: invalid mask argument");
}
} else {
if (mask)
free(mask);
usage("Error: Missing magic argument");
}
if (!strnlen(xbe->xbe_interpreter, IBE_INTERP_LEN_MAX)) {
usage("Error: Missing 'interpreter' argument");
}
return (0);
}
int
name_cmd(int argc, char *argv[], ximgact_binmisc_entry_t *xbe)
{
if (argc == 0)
usage("Required argument missing\n");
if (strlen(argv[0]) > IBE_NAME_MAX)
usage("'%s' string length longer than IBE_NAME_MAX (%d)",
IBE_NAME_MAX);
strlcpy(&xbe->xbe_name[0], argv[0], IBE_NAME_MAX);
return (0);
}
int
noname_cmd(__unused int argc, __unused char *argv[],
__unused ximgact_binmisc_entry_t *xbe)
{
return (0);
}
int
main(int argc, char **argv)
{
int error = 0, cmd = -1;
ximgact_binmisc_entry_t xbe_in, *xbe_inp = NULL;
ximgact_binmisc_entry_t xbe_out, *xbe_outp = NULL;
size_t xbe_in_sz = 0;
size_t xbe_out_sz = 0, *xbe_out_szp = NULL;
uint32_t i;
if (kldfind(KMOD_NAME) == -1) {
if (kldload(KMOD_NAME) == -1)
fatal("Can't load %s kernel module: %s",
KMOD_NAME, strerror(errno));
}
bzero(&xbe_in, sizeof(xbe_in));
bzero(&xbe_out, sizeof(xbe_out));
xbe_in.xbe_version = IBE_VERSION;
if (argc < 2)
usage("Error: requires at least one argument");
argc--, argv++;
cmd = demux_cmd(argc, argv);
if (cmd == -1)
usage("Error: Unknown command \"%s\"", argv[0]);
argc--, argv++;
error = (*cmds[cmd].func)(argc, argv, &xbe_in);
if (error)
usage("Can't parse command-line for '%s' command",
cmds[cmd].name);
if (cmd != CMD_LIST) {
xbe_inp = &xbe_in;
xbe_in_sz = sizeof(xbe_in);
} else
xbe_out_szp = &xbe_out_sz;
if (cmd == CMD_LOOKUP) {
xbe_out_sz = sizeof(xbe_out);
xbe_outp = &xbe_out;
xbe_out_szp = &xbe_out_sz;
}
error = sysctlbyname(cmd_sysctl_name[cmd], xbe_outp, xbe_out_szp,
xbe_inp, xbe_in_sz);
if (error)
switch(errno) {
case EINVAL:
usage("Invalid interpreter name or --interpreter, "
"--magic, --mask, or --size argument value");
break;
case EEXIST:
usage("'%s' is not unique in activator list",
xbe_in.xbe_name);
break;
case ENOENT:
usage("'%s' is not found in activator list",
xbe_in.xbe_name);
break;
case ENOSPC:
fatal("Fatal: no more room in the activator list "
"(limited to %d enties)", IBE_MAX_ENTRIES);
break;
case EPERM:
usage("Insufficient privileges for '%s' command",
cmds[cmd].name);
break;
default:
fatal("Fatal: sysctlbyname() returned: %s",
strerror(errno));
break;
}
if (cmd == CMD_LOOKUP)
printxbe(xbe_outp);
if (cmd == CMD_LIST && xbe_out_sz > 0) {
xbe_outp = malloc(xbe_out_sz);
if (!xbe_outp)
fatal("Fatal: out of memory");
while(1) {
size_t osize = xbe_out_sz;
error = sysctlbyname(cmd_sysctl_name[cmd], xbe_outp,
&xbe_out_sz, NULL, 0);
if (error == -1 && errno == ENOMEM &&
xbe_out_sz == osize) {
/*
* Buffer too small. Increase it by one
* entry.
*/
xbe_out_sz += sizeof(xbe_out);
xbe_outp = realloc(xbe_outp, xbe_out_sz);
if (!xbe_outp)
fatal("Fatal: out of memory");
} else
break;
}
if (error) {
free(xbe_outp);
fatal("Fatal: %s", strerror(errno));
}
for(i = 0; i < (xbe_out_sz / sizeof(xbe_out)); i++)
printxbe(&xbe_outp[i]);
}
return (error);
}