freenx-server/nxviewer-passwd/nxpasswd/vncpasswd.c.TIGHTVNC.original
2025-08-08 20:28:57 +02:00

287 lines
7.5 KiB
Plaintext

/*
* Copyright (C) 2002-2003 Constantin Kaplinsky. All Rights Reserved.
* Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
/*
* vncpasswd: A standalone program which gets and verifies a password,
* encrypts it, and stores it to a file. Optionally, it does
* the same for a second (view-only) password. Always ignore
* anything after 8 characters, since this is what Solaris
* getpass() does anyway.
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include "vncauth.h"
static void usage(char *argv[]);
static char *getenv_safe(char *name, size_t maxlen);
static void mkdir_and_check(char *dirname, int be_strict);
static int read_password(char *result);
static int ask_password(char *result);
int main(int argc, char *argv[])
{
int read_from_stdin = 0;
int make_directory = 0;
int check_strictly = 0;
char passwd1[9];
char passwd2[9];
char *passwd2_ptr;
char yesno[2];
char passwdDir[256];
char passwdFile[256];
int i;
if (argc == 1) {
sprintf(passwdDir, "%s/.vnc", getenv_safe("HOME", 240));
sprintf(passwdFile, "%s/passwd", passwdDir);
read_from_stdin = 0;
make_directory = 1;
check_strictly = 0;
} else if (argc == 2) {
if (strcmp(argv[1], "-t") == 0) {
sprintf(passwdDir, "/tmp/%s-vnc", getenv_safe("USER", 32));
sprintf(passwdFile, "%s/passwd", passwdDir);
read_from_stdin = 0;
make_directory = 1;
check_strictly = 1;
} else if (strcmp(argv[1], "-f") == 0) {
strcpy(passwdFile, "-");
read_from_stdin = 1;
make_directory = 0;
check_strictly = 0;
} else {
if (strlen(argv[1]) > 255) {
fprintf(stderr, "Error: file name too long\n");
exit(1);
}
strcpy(passwdFile, argv[1]);
read_from_stdin = 0;
make_directory = 0;
check_strictly = 0;
}
} else {
usage(argv);
}
if (make_directory) {
fprintf(stderr, "Using password file %s\n", passwdFile);
mkdir_and_check(passwdDir, check_strictly);
}
passwd2_ptr = NULL;
if (read_from_stdin) {
/* Read one or two passwords from stdin */
if (!read_password(passwd1)) {
fprintf(stderr, "Could not read password\n");
exit(1);
}
if (read_password(passwd2)) {
passwd2_ptr = passwd2;
}
} else {
/* Ask the primary (full-control) password. */
if (!ask_password(passwd1)) {
exit(1);
}
/* Optionally, ask the second (view-only) password. */
/* FIXME: Is it correct to read from stdin here? */
fprintf(stderr, "Would you like to enter a view-only password (y/n)? ");
if (fgets(yesno, 2, stdin) != NULL && strchr("Yy", yesno[0]) != NULL) {
if (ask_password(passwd2)) {
passwd2_ptr = passwd2;
}
}
}
/* Actually write the passwords. */
if (!vncEncryptAndStorePasswd2(passwd1, passwd2_ptr, passwdFile)) {
memset(passwd1, 0, strlen(passwd1));
memset(passwd2, 0, strlen(passwd2));
fprintf(stderr, "Cannot write password file %s\n", passwdFile);
exit(1);
}
/* Zero the memory. */
memset(passwd1, 0, strlen(passwd1));
memset(passwd2, 0, strlen(passwd2));
return 0;
}
static void usage(char *argv[])
{
fprintf(stderr,
"Usage: %s [FILE]\n"
" %s -t\n",
argv[0], argv[0], argv[0]);
exit(1);
}
static char *getenv_safe(char *name, size_t maxlen)
{
char *result;
result = getenv(name);
if (result == NULL) {
fprintf(stderr, "Error: no %s environment variable\n", name);
exit(1);
}
if (strlen(result) > maxlen) {
fprintf(stderr, "Error: %s environment variable string too long\n", name);
exit(1);
}
return result;
}
/*
* Check if the specified vnc directory exists, create it if
* necessary, and perform a number of sanity checks.
*/
static void mkdir_and_check(char *dirname, int be_strict)
{
struct stat stbuf;
if (lstat(dirname, &stbuf) != 0) {
if (errno != ENOENT) {
fprintf(stderr, "lstat() failed for %s: %s\n", dirname, strerror(errno));
exit(1);
}
fprintf(stderr, "VNC directory %s does not exist, creating.\n", dirname);
if (mkdir(dirname, S_IRWXU) == -1) {
fprintf(stderr, "Error creating directory %s: %s\n",
dirname, strerror(errno));
exit(1);
}
}
if (lstat(dirname, &stbuf) != 0) {
fprintf(stderr, "Error in lstat() for %s: %s\n", dirname, strerror(errno));
exit(1);
}
if (!S_ISDIR(stbuf.st_mode)) {
fprintf(stderr, "Error: %s is not a directory\n", dirname);
exit(1);
}
if (stbuf.st_uid != getuid()) {
fprintf(stderr, "Error: bad ownership on %s\n", dirname);
exit(1);
}
if (be_strict && ((S_IRWXG|S_IRWXO) & stbuf.st_mode)){
fprintf(stderr, "Error: bad access modes on %s\n", dirname);
exit(1);
}
}
/*
* Read a password from stdin. The password is terminated either by an
* end of line, or by the end of stdin data. Return 1 on success, 0 on
* error. On success, the password will be stored in the specified
* 9-byte buffer.
*/
static int read_password(char *result)
{
char passwd[256];
char *ptr;
/* Try to read the password. */
if (fgets(passwd, 256, stdin) == NULL)
return 0;
/* Remove the newline if present. */
ptr = strchr(passwd, '\n');
if (ptr != NULL)
*ptr = '\0';
/* Truncate if necessary. */
if (strlen(passwd) > 8) {
memset(passwd + 8, 0, strlen(passwd) - 8);
fprintf(stderr, "Warning: password truncated to the length of 8.\n");
}
/* Save the password and zero our copies. */
strcpy(result, passwd);
memset(passwd, 0, strlen(passwd));
return 1;
}
/*
* Ask a password, check its length and ask to confirm it once more.
* Return 1 on success, 0 on error. On success, the password will be
* stored in the specified 9-byte buffer.
*/
static int ask_password(char *result)
{
char *passwd;
char passwd_copy[9];
while (1) {
passwd = getpass("Password: ");
if (!passwd) {
fprintf(stderr, "Can't get password: not a tty?\n");
return 0;
}
if (strlen(passwd) < 6) {
fprintf(stderr, "Password too short\n");
return 0;
}
if (strlen(passwd) > 8) {
memset(passwd + 8, 0, strlen(passwd) - 8);
fprintf(stderr, "Warning: password truncated to the length of 8.\n");
}
strcpy(passwd_copy, passwd);
passwd = getpass("Verify: ");
if (strlen(passwd) > 8)
memset(passwd + 8, 0, strlen(passwd) - 8);
if (strcmp(passwd, passwd_copy) == 0)
break; /* success */
fprintf(stderr,"Passwords do not match. Please try again.\n\n");
}
/* Save the password and zero our copies. */
strcpy(result, passwd);
memset(passwd, 0, strlen(passwd));
memset(passwd_copy, 0, strlen(passwd_copy));
return 1;
}