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/*
* Copyright (c) 1998, by Sun Microsystems, Inc.
* All rights reserved.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
/*
* safechown changes the owner ship of src to uid. If the mode parameter
* does not equal -1 changes the mode of src as well.
*
* return -1 on failure and 0 on success.
*/
int
safechown(const char *src, uid_t uid, gid_t gid, int mode)
{
int fd;
struct stat fdbuf;
struct stat lbuf;
if ((fd = open(src, O_RDONLY, 0)) == -1)
return (-1);
if (fstat(fd, &fdbuf)) {
close(fd);
return (-1);
}
/* Make sure non directories are not hard links */
if (!S_ISDIR(fdbuf.st_mode) && fdbuf.st_nlink != 1) {
close(fd);
return (-1);
}
if (lstat(src, &lbuf)) {
close(fd);
return (-1);
}
/* Make sure file is not a symlink */
if (fdbuf.st_ino != lbuf.st_ino || fdbuf.st_dev != lbuf.st_dev ||
fdbuf.st_mode != lbuf.st_mode) {
close(fd);
return (-1);
}
/* we should probably get the primary group id for uid here */
if (fchown(fd, uid, gid)) {
close(fd);
return (-1);
}
if (mode != -1) {
if (fchmod(fd, (mode_t)mode)) {
close(fd);
return (-1);
}
}
close(fd);
return (0);
}
#ifdef TEST
void
usage(char *prg)
{
fprintf(stderr, "Usage %s [-u uid] [-m mode] source\n", prg);
exit(1);
}
main(int argc, char *argv[])
{
int opt;
int mode = -1;
uid_t uid = 0;
while ((opt = getopt(argc, argv, "m:u:")) != EOF) {
switch (opt) {
case 'm':
mode = strtol(optarg, 0, 8);
break;
case 'u':
uid = atoi(optarg);
break;
default:
usage(argv[0]);
}
}
if (argc - optind != 1)
usage(argv[0]);
if (safechown(argv[optind], uid, getgid(), mode)) {
perror("safechown");
exit(1);
}
return (0);
}
#endif /* TEST */
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