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/* vi: set sw=4 ts=4: */
/*
* deluser (remove lusers from the system ;) for TinyLogin
*
* Copyright (C) 1999 by Lineo, inc. and John Beppu
* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
* Unified with delgroup by Tito Ragusa <farmatito@tiscali.it>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
*/
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "busybox.h"
/* where to start and stop deletion */
typedef struct {
size_t start;
size_t stop;
} Bounds;
/* An interesting side-effect of boundary()'s
* implementation is that the first user (typically root)
* cannot be removed. Let's call it a feature. */
static inline Bounds boundary(const char *buffer, const char *login)
{
char needle[256];
char *start;
char *stop;
Bounds b;
snprintf(needle, 256, "\n%s:", login);
needle[255] = 0;
start = strstr(buffer, needle);
if (!start) {
b.start = 0;
b.stop = 0;
return b;
}
start++;
stop = strchr(start, '\n');
b.start = start - buffer;
b.stop = stop - buffer;
return b;
}
/* grep -v ^login (except it only deletes the first match) */
/* ...in fact, I think I'm going to simplify this later */
static void del_line_matching(const char *login, const char *filename)
{
char *buffer;
FILE *passwd;
Bounds b;
struct stat statbuf;
if ((passwd = bb_wfopen(filename, "r"))) {
xstat(filename, &statbuf);
buffer = (char *) xmalloc(statbuf.st_size * sizeof(char));
fread(buffer, statbuf.st_size, sizeof(char), passwd);
fclose(passwd);
/* find the user to remove */
b = boundary(buffer, login);
if (b.stop != 0) {
/* write the file w/o the user */
if ((passwd = bb_wfopen(filename, "w"))) {
fwrite(buffer, (b.start - 1), sizeof(char), passwd);
fwrite(&buffer[b.stop], (statbuf.st_size - b.stop), sizeof(char), passwd);
fclose(passwd);
}
} else {
bb_error_msg("Can't find '%s' in '%s'", login, filename);
}
free(buffer);
}
}
int deluser_main(int argc, char **argv)
{
if (argc != 2) {
bb_show_usage();
} else {
if (ENABLE_DELUSER && bb_applet_name[3] == 'u') {
del_line_matching(argv[1], bb_path_passwd_file);
if (ENABLE_FEATURE_SHADOWPASSWDS)
del_line_matching(argv[1], bb_path_shadow_file);
}
del_line_matching(argv[1], bb_path_group_file);
if (ENABLE_FEATURE_SHADOWPASSWDS)
del_line_matching(argv[1], bb_path_gshadow_file);
}
return (EXIT_SUCCESS);
}
/* $Id: deluser.c,v 1.4 2003/07/14 20:20:45 andersen Exp $ */
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