60 lines
1.6 KiB
C
60 lines
1.6 KiB
C
/* Encrypting Passwords
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Copyright (C) 1991-2022 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License
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as published by the Free Software Foundation; either version 2
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of the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, see <https://www.gnu.org/licenses/>.
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*/
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#include <stdio.h>
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#include <unistd.h>
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#include <crypt.h>
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int
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main(void)
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{
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unsigned char ubytes[16];
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char salt[20];
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const char *const saltchars =
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"./0123456789ABCDEFGHIJKLMNOPQRST"
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"UVWXYZabcdefghijklmnopqrstuvwxyz";
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char *hash;
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int i;
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/* Retrieve 16 unpredictable bytes from the operating system. */
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if (getentropy (ubytes, sizeof ubytes))
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{
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perror ("getentropy");
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return 1;
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}
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/* Use them to fill in the salt string. */
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salt[0] = '$';
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salt[1] = '5'; /* SHA-256 */
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salt[2] = '$';
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for (i = 0; i < 16; i++)
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salt[3+i] = saltchars[ubytes[i] & 0x3f];
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salt[3+i] = '\0';
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/* Read in the user's passphrase and hash it. */
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hash = crypt (getpass ("Enter new passphrase: "), salt);
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if (!hash || hash[0] == '*')
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{
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perror ("crypt");
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return 1;
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}
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/* Print the results. */
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puts (hash);
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return 0;
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}
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