path.c

解Unix密码的程序john1.

/*
 * This file is part of John the Ripper password cracker,
 * Copyright (c) 1996-2000 by Solar Designer
 */

#include <string.h>

#include "misc.h"
#include "params.h"
#include "memory.h"
#include "path.h"

static char *john_home_path = NULL;
static int john_home_length;

#if JOHN_SYSTEMWIDE
#include <unistd.h>
#include <errno.h>
#include <pwd.h>
#include <sys/types.h>
#include <sys/stat.h>

static char *user_home_path = NULL;
static int user_home_length;
#endif

void path_init(char **argv)
{
#if JOHN_SYSTEMWIDE
	struct passwd *pw;
#ifdef JOHN_PRIVATE_HOME
	char *private;
#endif
#else
	char *pos;
#endif

#if JOHN_SYSTEMWIDE
	john_home_path = mem_alloc(PATH_BUFFER_SIZE);
	strnzcpy(john_home_path, JOHN_SYSTEMWIDE_HOME "/", PATH_BUFFER_SIZE);
	john_home_length = strlen(john_home_path);

	if (user_home_path) return;
	pw = getpwuid(getuid());
	endpwent();
	if (!pw) return;

	user_home_length = strlen(pw->pw_dir) + 1;
	if (user_home_length >= PATH_BUFFER_SIZE) return;

	user_home_path = mem_alloc(PATH_BUFFER_SIZE);
	memcpy(user_home_path, pw->pw_dir, user_home_length - 1);
	user_home_path[user_home_length - 1] = '/';

#ifdef JOHN_PRIVATE_HOME
	private = path_expand(JOHN_PRIVATE_HOME);
	if (mkdir(private, S_IRUSR | S_IWUSR | S_IXUSR)) {
		if (errno != EEXIST) pexit("mkdir: %s", private);
	} else
		fprintf(stderr, "Created directory: %s\n", private);
#endif
#else
	if (argv[0])
	if (!john_home_path && (pos = strrchr(argv[0], '/'))) {
		john_home_length = pos - argv[0] + 1;
		if (john_home_length >= PATH_BUFFER_SIZE) return;

		john_home_path = mem_alloc(PATH_BUFFER_SIZE);
		memcpy(john_home_path, argv[0], john_home_length);
	}
#endif
}

char *path_expand(char *name)
{
	if (!strncmp(name, "$JOHN/", 6)) {
		if (john_home_path &&
		    john_home_length + strlen(name) - 6 < PATH_BUFFER_SIZE) {
			strnzcpy(&john_home_path[john_home_length], &name[6],
				PATH_BUFFER_SIZE - john_home_length);
			return john_home_path;
		}
		return name + 6;
	}

#if JOHN_SYSTEMWIDE
	if (!strncmp(name, "~/", 2)) {
		if (user_home_path &&
		    user_home_length + strlen(name) - 2 < PATH_BUFFER_SIZE) {
			strnzcpy(&user_home_path[user_home_length], &name[2],
				PATH_BUFFER_SIZE - user_home_length);
			return user_home_path;
		}
		return name + 2;
	}
#endif

	return name;
}

void path_done(void)
{
	mem_free((void **)&john_home_path);
#if JOHN_SYSTEMWIDE
	mem_free((void **)&user_home_path);
#endif
}