freebsd-src/sbin/ldconfig/elfhints.c
David E. O'Brien 5e6220d9d0 * include/elf.h has been repo copied to include/elf-hints.h, and it no
longer includes machine/elf.h.
* consumers of elf.h now use the minimalist elf header possible.

This change is motivated by Binutils 2.11.0 and too much clashing over
our base elf headers and the Binutils elf headers.
2001-05-02 23:56:21 +00:00

303 lines
7.6 KiB
C

/*-
* Copyright (c) 1998 John D. Polstra
* 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <ctype.h>
#include <dirent.h>
#include <elf-hints.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "ldconfig.h"
#define MAXDIRS 1024 /* Maximum directories in path */
#define MAXFILESIZE (16*1024) /* Maximum hints file size */
static void add_dir(const char *, const char *, int);
static void read_dirs_from_file(const char *, const char *);
static void read_elf_hints(const char *, int);
static void write_elf_hints(const char *);
static const char *dirs[MAXDIRS];
static int ndirs;
int insecure;
static void
add_dir(const char *hintsfile, const char *name, int trusted)
{
struct stat stbuf;
int i;
/* Do some security checks */
if (!trusted && !insecure) {
if (stat(name, &stbuf) == -1) {
warn("%s", name);
return;
}
if (stbuf.st_uid != 0) {
warnx("%s: ignoring directory not owned by root", name);
return;
}
if ((stbuf.st_mode & S_IWOTH) != 0) {
warnx("%s: ignoring world-writable directory", name);
return;
}
if ((stbuf.st_mode & S_IWGRP) != 0) {
warnx("%s: ignoring group-writable directory", name);
return;
}
}
for (i = 0; i < ndirs; i++)
if (strcmp(dirs[i], name) == 0)
return;
if (ndirs >= MAXDIRS)
errx(1, "\"%s\": Too many directories in path", hintsfile);
dirs[ndirs++] = name;
}
void
list_elf_hints(const char *hintsfile)
{
int i;
int nlibs;
read_elf_hints(hintsfile, 1);
printf("%s:\n", hintsfile);
printf("\tsearch directories:");
for (i = 0; i < ndirs; i++)
printf("%c%s", i == 0 ? ' ' : ':', dirs[i]);
printf("\n");
nlibs = 0;
for (i = 0; i < ndirs; i++) {
DIR *dirp;
struct dirent *dp;
if ((dirp = opendir(dirs[i])) == NULL)
continue;
while ((dp = readdir(dirp)) != NULL) {
int len;
int namelen;
const char *name;
const char *vers;
/* Name can't be shorter than "libx.so.0" */
if ((len = strlen(dp->d_name)) < 9 ||
strncmp(dp->d_name, "lib", 3) != 0)
continue;
name = dp->d_name + 3;
vers = dp->d_name + len;
while (vers > dp->d_name && isdigit(*(vers-1)))
vers--;
if (vers == dp->d_name + len)
continue;
if (vers < dp->d_name + 4 ||
strncmp(vers - 4, ".so.", 4) != 0)
continue;
/* We have a valid shared library name. */
namelen = (vers - 4) - name;
printf("\t%d:-l%.*s.%s => %s/%s\n", nlibs,
namelen, name, vers, dirs[i], dp->d_name);
nlibs++;
}
closedir(dirp);
}
}
static void
read_dirs_from_file(const char *hintsfile, const char *listfile)
{
FILE *fp;
char buf[MAXPATHLEN];
int linenum;
if ((fp = fopen(listfile, "r")) == NULL)
err(1, "%s", listfile);
linenum = 0;
while (fgets(buf, sizeof buf, fp) != NULL) {
char *cp, *sp;
linenum++;
cp = buf;
/* Skip leading white space. */
while (isspace(*cp))
cp++;
if (*cp == '#' || *cp == '\0')
continue;
sp = cp;
/* Advance over the directory name. */
while (!isspace(*cp) && *cp != '\0')
cp++;
/* Terminate the string and skip trailing white space. */
if (*cp != '\0') {
*cp++ = '\0';
while (isspace(*cp))
cp++;
}
/* Now we had better be at the end of the line. */
if (*cp != '\0')
warnx("%s:%d: trailing characters ignored",
listfile, linenum);
if ((sp = strdup(sp)) == NULL)
errx(1, "Out of memory");
add_dir(hintsfile, sp, 0);
}
fclose(fp);
}
static void
read_elf_hints(const char *hintsfile, int must_exist)
{
int fd;
struct stat s;
void *mapbase;
struct elfhints_hdr *hdr;
char *strtab;
char *dirlist;
char *p;
if ((fd = open(hintsfile, O_RDONLY)) == -1) {
if (errno == ENOENT && !must_exist)
return;
err(1, "Cannot open \"%s\"", hintsfile);
}
if (fstat(fd, &s) == -1)
err(1, "Cannot stat \"%s\"", hintsfile);
if (s.st_size > MAXFILESIZE)
errx(1, "\"%s\" is unreasonably large", hintsfile);
/*
* We use a read-write, private mapping so that we can null-terminate
* some strings in it without affecting the underlying file.
*/
mapbase = mmap(NULL, s.st_size, PROT_READ|PROT_WRITE,
MAP_PRIVATE, fd, 0);
if (mapbase == MAP_FAILED)
err(1, "Cannot mmap \"%s\"", hintsfile);
close(fd);
hdr = (struct elfhints_hdr *)mapbase;
if (hdr->magic != ELFHINTS_MAGIC)
errx(1, "\"%s\": invalid file format", hintsfile);
if (hdr->version != 1)
errx(1, "\"%s\": unrecognized file version (%d)", hintsfile,
hdr->version);
strtab = (char *)mapbase + hdr->strtab;
dirlist = strtab + hdr->dirlist;
if (*dirlist != '\0')
while ((p = strsep(&dirlist, ":")) != NULL)
add_dir(hintsfile, p, 1);
}
void
update_elf_hints(const char *hintsfile, int argc, char **argv, int merge)
{
int i;
if (merge)
read_elf_hints(hintsfile, 0);
for (i = 0; i < argc; i++) {
struct stat s;
if (stat(argv[i], &s) == -1)
warn("warning: %s", argv[i]);
else if (S_ISREG(s.st_mode))
read_dirs_from_file(hintsfile, argv[i]);
else
add_dir(hintsfile, argv[i], 0);
}
write_elf_hints(hintsfile);
}
static void
write_elf_hints(const char *hintsfile)
{
struct elfhints_hdr hdr;
char *tempname;
int fd;
FILE *fp;
int i;
if (asprintf(&tempname, "%s.XXXXXX", hintsfile) == -1)
errx(1, "Out of memory");
if ((fd = mkstemp(tempname)) == -1)
err(1, "mkstemp(%s)", tempname);
if (fchmod(fd, 0444) == -1)
err(1, "fchmod(%s)", tempname);
if ((fp = fdopen(fd, "wb")) == NULL)
err(1, "fdopen(%s)", tempname);
hdr.magic = ELFHINTS_MAGIC;
hdr.version = 1;
hdr.strtab = sizeof hdr;
hdr.strsize = 0;
hdr.dirlist = 0;
memset(hdr.spare, 0, sizeof hdr.spare);
/* Count up the size of the string table. */
if (ndirs > 0) {
hdr.strsize += strlen(dirs[0]);
for (i = 1; i < ndirs; i++)
hdr.strsize += 1 + strlen(dirs[i]);
}
hdr.dirlistlen = hdr.strsize;
hdr.strsize++; /* For the null terminator */
/* Write the header. */
if (fwrite(&hdr, 1, sizeof hdr, fp) != sizeof hdr)
err(1, "%s: write error", tempname);
/* Write the strings. */
if (ndirs > 0) {
if (fputs(dirs[0], fp) == EOF)
err(1, "%s: write error", tempname);
for (i = 1; i < ndirs; i++)
if (fprintf(fp, ":%s", dirs[i]) < 0)
err(1, "%s: write error", tempname);
}
if (putc('\0', fp) == EOF || fclose(fp) == EOF)
err(1, "%s: write error", tempname);
if (rename(tempname, hintsfile) == -1)
err(1, "rename %s to %s", tempname, hintsfile);
free(tempname);
}