freebsd-src/usr.sbin/kldxref/kldxref.c
Luigi Rizzo 9cb138bb35 various cleanups including:
+ check a possible buffer overflow when creating a temp file,
  submitted by Christoph Mallon
+ remove stale struct definitions
+ clarify the use of dflag and remove useless checks

MFC after:	3 days
2009-01-06 14:23:38 +00:00

361 lines
8.5 KiB
C

/*
* Copyright (c) 2000, Boris Popov
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Boris Popov.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/exec.h>
#include <sys/queue.h>
#include <sys/kernel.h>
#include <sys/reboot.h>
#include <sys/linker.h>
#include <sys/stat.h>
#include <sys/module.h>
#define FREEBSD_ELF
#include <link.h>
#include <err.h>
#include <fts.h>
#include <string.h>
#include <machine/elf.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include "ef.h"
#define MAXRECSIZE 1024
#define check(val) if ((error = (val)) != 0) break
static int dflag; /* do not create a hint file, only write on stdout */
static int verbose;
static FILE *fxref; /* current hints file */
static const char *xref_file = "linker.hints";
/*
* A record is stored in the static buffer recbuf before going to disk.
*/
static char recbuf[MAXRECSIZE];
static int recpos; /* current write position */
static int reccnt; /* total record written to this file so far */
static void
intalign(void)
{
recpos = (recpos + sizeof(int) - 1) & ~(sizeof(int) - 1);
}
static void
record_start(void)
{
recpos = 0;
memset(recbuf, 0, MAXRECSIZE);
}
static int
record_end(void)
{
if (recpos == 0)
return 0;
reccnt++;
intalign();
fwrite(&recpos, sizeof(recpos), 1, fxref);
return fwrite(recbuf, recpos, 1, fxref) != 1 ? errno : 0;
}
static int
record_buf(const void *buf, int size)
{
if (MAXRECSIZE - recpos < size)
errx(1, "record buffer overflow");
memcpy(recbuf + recpos, buf, size);
recpos += size;
return 0;
}
/*
* An int is stored in host order and aligned
*/
static int
record_int(int val)
{
intalign();
return record_buf(&val, sizeof(val));
}
/*
* A string is stored as 1-byte length plus data, no padding
*/
static int
record_string(const char *str)
{
int len, error;
u_char val;
if (dflag)
return 0;
val = len = strlen(str);
if (len > 255)
errx(1, "string %s too long", str);
error = record_buf(&val, sizeof(val));
if (error)
return error;
return record_buf(str, len);
}
static int
parse_entry(struct mod_metadata *md, const char *cval,
struct elf_file *ef, const char *kldname)
{
struct mod_depend mdp;
struct mod_version mdv;
Elf_Off data = (Elf_Off)md->md_data;
int error = 0;
record_start();
switch (md->md_type) {
case MDT_DEPEND:
if (!dflag)
break;
check(EF_SEG_READ(ef, data, sizeof(mdp), &mdp));
printf(" depends on %s.%d (%d,%d)\n", cval,
mdp.md_ver_preferred, mdp.md_ver_minimum, mdp.md_ver_maximum);
break;
case MDT_VERSION:
check(EF_SEG_READ(ef, data, sizeof(mdv), &mdv));
if (dflag) {
printf(" interface %s.%d\n", cval, mdv.mv_version);
} else {
record_int(MDT_VERSION);
record_string(cval);
record_int(mdv.mv_version);
record_string(kldname);
}
break;
case MDT_MODULE:
if (dflag) {
printf(" module %s\n", cval);
} else {
record_int(MDT_MODULE);
record_string(cval);
record_string(kldname);
}
break;
default:
warnx("unknown metadata record %d in file %s", md->md_type, kldname);
}
if (!error)
record_end();
return error;
}
static int
read_kld(char *filename, char *kldname)
{
struct mod_metadata md;
struct elf_file ef;
void **p, **orgp;
int error, eftype, nmlen;
long start, finish, entries;
char kldmodname[MAXMODNAME + 1], cval[MAXMODNAME + 1], *cp;
if (verbose || dflag)
printf("%s\n", filename);
error = ef_open(filename, &ef, verbose);
if (error) {
error = ef_obj_open(filename, &ef, verbose);
if (error) {
if (verbose)
warnc(error, "elf_open(%s)", filename);
return error;
}
}
eftype = EF_GET_TYPE(&ef);
if (eftype != EFT_KLD && eftype != EFT_KERNEL) {
EF_CLOSE(&ef);
return 0;
}
if (!dflag) {
cp = strrchr(kldname, '.');
nmlen = (cp != NULL) ? cp - kldname : (int)strlen(kldname);
if (nmlen > MAXMODNAME)
nmlen = MAXMODNAME;
strlcpy(kldmodname, kldname, nmlen);
/* fprintf(fxref, "%s:%s:%d\n", kldmodname, kldname, 0);*/
}
do {
check(EF_LOOKUP_SET(&ef, MDT_SETNAME, &start, &finish,
&entries));
check(EF_SEG_READ_ENTRY_REL(&ef, start, sizeof(*p) * entries,
(void *)&p));
orgp = p;
while(entries--) {
check(EF_SEG_READ_REL(&ef, (Elf_Off)*p, sizeof(md),
&md));
p++;
check(EF_SEG_READ(&ef, (Elf_Off)md.md_cval,
sizeof(cval), cval));
cval[MAXMODNAME] = '\0';
parse_entry(&md, cval, &ef, kldname);
}
if (error)
warnc(error, "error while reading %s", filename);
free(orgp);
} while(0);
EF_CLOSE(&ef);
return error;
}
/*
* Create a temp file in directory root, make sure we don't
* overflow the buffer for the destination name
*/
static FILE *
maketempfile(char *dest, const char *root)
{
char *p;
int n, fd;
p = strrchr(root, '/');
n = p != NULL ? p - root + 1 : 0;
if (snprintf(dest, MAXPATHLEN, "%.*slhint.XXXXXX", n, root) >=
MAXPATHLEN) {
errno = ENAMETOOLONG;
return NULL;
}
fd = mkstemp(dest);
if (fd < 0)
return NULL;
fchmod(fd, 0644); /* nothing secret in the file */
return fdopen(fd, "w+");
}
static char xrefname[MAXPATHLEN], tempname[MAXPATHLEN];
static void
usage(void)
{
fprintf(stderr, "%s\n",
"usage: kldxref [-Rdv] [-f hintsfile] path ..."
);
exit(1);
}
int
main(int argc, char *argv[])
{
FTS *ftsp;
FTSENT *p;
int opt, fts_options, ival;
struct stat sb;
fts_options = FTS_PHYSICAL;
while ((opt = getopt(argc, argv, "Rdf:v")) != -1) {
switch (opt) {
case 'd': /* no hint file, only print on stdout */
dflag = 1;
break;
case 'f': /* use this name instead of linker.hints */
xref_file = optarg;
break;
case 'v':
verbose++;
break;
case 'R': /* recurse on directories */
fts_options |= FTS_COMFOLLOW;
break;
default:
usage();
/* NOTREACHED */
}
}
if (argc - optind < 1)
usage();
argc -= optind;
argv += optind;
if (stat(argv[0], &sb) != 0)
err(1, "%s", argv[0]);
if ((sb.st_mode & S_IFDIR) == 0) {
errno = ENOTDIR;
err(1, "%s", argv[0]);
}
ftsp = fts_open(argv, fts_options, 0);
if (ftsp == NULL)
exit(1);
for (;;) {
p = fts_read(ftsp);
if ((p == NULL || p->fts_info == FTS_D) && fxref) {
/* close and rename the current hint file */
fclose(fxref);
fxref = NULL;
if (reccnt) {
rename(tempname, xrefname);
} else {
/* didn't find any entry, ignore this file */
unlink(tempname);
unlink(xrefname);
}
}
if (p == NULL)
break;
if (p->fts_info == FTS_D && !dflag) {
/* visiting a new directory, create a new hint file */
snprintf(xrefname, sizeof(xrefname), "%s/%s",
ftsp->fts_path, xref_file);
fxref = maketempfile(tempname, ftsp->fts_path);
if (fxref == NULL)
err(1, "can't create %s", tempname);
ival = 1;
fwrite(&ival, sizeof(ival), 1, fxref);
reccnt = 0;
}
/* skip non-files or .symbols entries */
if (p->fts_info != FTS_F)
continue;
if (p->fts_namelen >= 8 &&
strcmp(p->fts_name + p->fts_namelen - 8, ".symbols") == 0)
continue;
read_kld(p->fts_path, p->fts_name);
}
fts_close(ftsp);
return 0;
}