Copy scryptenc.{c,h} to genpass.{c,h}
This commit is contained in:
Chris Oei
parent
84c31465be
commit
324f7a8124
2 changed files with 718 additions and 0 deletions
606
lib/genpass/genpass.c
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606
lib/genpass/genpass.c
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@ -0,0 +1,606 @@
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/*-
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* Copyright 2009 Colin Percival
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* This file was originally written by Colin Percival as part of the Tarsnap
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* online backup system.
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*/
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#include "scrypt_platform.h"
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#include <errno.h>
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#include <fcntl.h>
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#include <stdint.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <openssl/aes.h>
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#include "crypto_aesctr.h"
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#include "crypto_scrypt.h"
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#include "memlimit.h"
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#include "scryptenc_cpuperf.h"
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#include "sha256.h"
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#include "sysendian.h"
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#include "scryptenc.h"
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#define ENCBLOCK 65536
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static int pickparams(size_t, double, double,
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int *, uint32_t *, uint32_t *);
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static int checkparams(size_t, double, double, int, uint32_t, uint32_t);
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static int getsalt(uint8_t[32]);
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static int
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pickparams(size_t maxmem, double maxmemfrac, double maxtime,
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int * logN, uint32_t * r, uint32_t * p)
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{
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size_t memlimit;
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double opps;
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double opslimit;
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double maxN, maxrp;
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int rc;
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/* Figure out how much memory to use. */
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if (memtouse(maxmem, maxmemfrac, &memlimit))
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return (1);
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/* Figure out how fast the CPU is. */
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if ((rc = scryptenc_cpuperf(&opps)) != 0)
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return (rc);
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opslimit = opps * maxtime;
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/* Allow a minimum of 2^15 salsa20/8 cores. */
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if (opslimit < 32768)
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opslimit = 32768;
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/* Fix r = 8 for now. */
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*r = 8;
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/*
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* The memory limit requires that 128Nr <= memlimit, while the CPU
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* limit requires that 4Nrp <= opslimit. If opslimit < memlimit/32,
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* opslimit imposes the stronger limit on N.
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*/
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#ifdef DEBUG
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fprintf(stderr, "Requiring 128Nr <= %zu, 4Nrp <= %f\n",
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memlimit, opslimit);
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#endif
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if (opslimit < memlimit/32) {
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/* Set p = 1 and choose N based on the CPU limit. */
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*p = 1;
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maxN = opslimit / (*r * 4);
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for (*logN = 1; *logN < 63; *logN += 1) {
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if ((uint64_t)(1) << *logN > maxN / 2)
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break;
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}
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} else {
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/* Set N based on the memory limit. */
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maxN = memlimit / (*r * 128);
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for (*logN = 1; *logN < 63; *logN += 1) {
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if ((uint64_t)(1) << *logN > maxN / 2)
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break;
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}
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/* Choose p based on the CPU limit. */
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maxrp = (opslimit / 4) / ((uint64_t)(1) << *logN);
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if (maxrp > 0x3fffffff)
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maxrp = 0x3fffffff;
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*p = (uint32_t)(maxrp) / *r;
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}
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#ifdef DEBUG
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fprintf(stderr, "N = %zu r = %d p = %d\n",
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(size_t)(1) << *logN, (int)(*r), (int)(*p));
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#endif
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/* Success! */
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return (0);
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}
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static int
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checkparams(size_t maxmem, double maxmemfrac, double maxtime,
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int logN, uint32_t r, uint32_t p)
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{
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size_t memlimit;
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double opps;
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double opslimit;
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uint64_t N;
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int rc;
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/* Figure out the maximum amount of memory we can use. */
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if (memtouse(maxmem, maxmemfrac, &memlimit))
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return (1);
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/* Figure out how fast the CPU is. */
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if ((rc = scryptenc_cpuperf(&opps)) != 0)
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return (rc);
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opslimit = opps * maxtime;
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/* Sanity-check values. */
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if ((logN < 1) || (logN > 63))
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return (7);
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if ((uint64_t)(r) * (uint64_t)(p) >= 0x40000000)
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return (7);
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/* Check limits. */
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N = (uint64_t)(1) << logN;
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if ((memlimit / N) / r < 128)
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return (9);
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if ((opslimit / N) / (r * p) < 4)
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return (10);
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/* Success! */
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return (0);
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}
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static int
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getsalt(uint8_t salt[32])
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{
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int fd;
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ssize_t lenread;
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uint8_t * buf = salt;
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size_t buflen = 32;
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/* Open /dev/urandom. */
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if ((fd = open("/dev/urandom", O_RDONLY)) == -1)
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goto err0;
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/* Read bytes until we have filled the buffer. */
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while (buflen > 0) {
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if ((lenread = read(fd, buf, buflen)) == -1)
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goto err1;
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/* The random device should never EOF. */
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if (lenread == 0)
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goto err1;
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/* We're partly done. */
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buf += lenread;
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buflen -= lenread;
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}
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/* Close the device. */
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while (close(fd) == -1) {
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if (errno != EINTR)
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goto err0;
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}
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/* Success! */
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return (0);
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err1:
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close(fd);
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err0:
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/* Failure! */
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return (4);
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}
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static int
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scryptenc_setup(uint8_t header[96], uint8_t dk[64],
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const uint8_t * passwd, size_t passwdlen,
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size_t maxmem, double maxmemfrac, double maxtime)
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{
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uint8_t salt[32];
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uint8_t hbuf[32];
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int logN;
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uint64_t N;
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uint32_t r;
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uint32_t p;
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SHA256_CTX ctx;
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uint8_t * key_hmac = &dk[32];
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HMAC_SHA256_CTX hctx;
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int rc;
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/* Pick values for N, r, p. */
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if ((rc = pickparams(maxmem, maxmemfrac, maxtime,
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&logN, &r, &p)) != 0)
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return (rc);
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N = (uint64_t)(1) << logN;
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/* Get some salt. */
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if ((rc = getsalt(salt)) != 0)
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return (rc);
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/* Generate the derived keys. */
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if (crypto_scrypt(passwd, passwdlen, salt, 32, N, r, p, dk, 64))
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return (3);
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/* Construct the file header. */
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memcpy(header, "scrypt", 6);
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header[6] = 0;
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header[7] = logN;
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be32enc(&header[8], r);
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be32enc(&header[12], p);
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memcpy(&header[16], salt, 32);
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/* Add header checksum. */
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SHA256_Init(&ctx);
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SHA256_Update(&ctx, header, 48);
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SHA256_Final(hbuf, &ctx);
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memcpy(&header[48], hbuf, 16);
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/* Add header signature (used for verifying password). */
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HMAC_SHA256_Init(&hctx, key_hmac, 32);
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HMAC_SHA256_Update(&hctx, header, 64);
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HMAC_SHA256_Final(hbuf, &hctx);
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memcpy(&header[64], hbuf, 32);
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/* Success! */
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return (0);
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}
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static int
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scryptdec_setup(const uint8_t header[96], uint8_t dk[64],
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const uint8_t * passwd, size_t passwdlen,
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size_t maxmem, double maxmemfrac, double maxtime)
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{
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uint8_t salt[32];
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uint8_t hbuf[32];
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int logN;
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uint32_t r;
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uint32_t p;
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uint64_t N;
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SHA256_CTX ctx;
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uint8_t * key_hmac = &dk[32];
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HMAC_SHA256_CTX hctx;
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int rc;
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/* Parse N, r, p, salt. */
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logN = header[7];
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r = be32dec(&header[8]);
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p = be32dec(&header[12]);
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memcpy(salt, &header[16], 32);
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/* Verify header checksum. */
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SHA256_Init(&ctx);
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SHA256_Update(&ctx, header, 48);
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SHA256_Final(hbuf, &ctx);
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if (memcmp(&header[48], hbuf, 16))
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return (7);
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/*
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* Check whether the provided parameters are valid and whether the
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* key derivation function can be computed within the allowed memory
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* and CPU time.
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*/
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if ((rc = checkparams(maxmem, maxmemfrac, maxtime, logN, r, p)) != 0)
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return (rc);
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/* Compute the derived keys. */
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N = (uint64_t)(1) << logN;
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if (crypto_scrypt(passwd, passwdlen, salt, 32, N, r, p, dk, 64))
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return (3);
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/* Check header signature (i.e., verify password). */
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HMAC_SHA256_Init(&hctx, key_hmac, 32);
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HMAC_SHA256_Update(&hctx, header, 64);
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HMAC_SHA256_Final(hbuf, &hctx);
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if (memcmp(hbuf, &header[64], 32))
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return (11);
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/* Success! */
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return (0);
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}
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/**
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* scryptenc_buf(inbuf, inbuflen, outbuf, passwd, passwdlen,
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* maxmem, maxmemfrac, maxtime):
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* Encrypt inbuflen bytes from inbuf, writing the resulting inbuflen + 128
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* bytes to outbuf.
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*/
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int
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scryptenc_buf(const uint8_t * inbuf, size_t inbuflen, uint8_t * outbuf,
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const uint8_t * passwd, size_t passwdlen,
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size_t maxmem, double maxmemfrac, double maxtime)
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{
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uint8_t dk[64];
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uint8_t hbuf[32];
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uint8_t header[96];
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uint8_t * key_enc = dk;
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uint8_t * key_hmac = &dk[32];
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int rc;
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HMAC_SHA256_CTX hctx;
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AES_KEY key_enc_exp;
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struct crypto_aesctr * AES;
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/* Generate the header and derived key. */
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if ((rc = scryptenc_setup(header, dk, passwd, passwdlen,
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maxmem, maxmemfrac, maxtime)) != 0)
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return (rc);
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/* Copy header into output buffer. */
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memcpy(outbuf, header, 96);
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/* Encrypt data. */
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if (AES_set_encrypt_key(key_enc, 256, &key_enc_exp))
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return (5);
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if ((AES = crypto_aesctr_init(&key_enc_exp, 0)) == NULL)
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return (6);
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crypto_aesctr_stream(AES, inbuf, &outbuf[96], inbuflen);
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crypto_aesctr_free(AES);
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/* Add signature. */
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HMAC_SHA256_Init(&hctx, key_hmac, 32);
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HMAC_SHA256_Update(&hctx, outbuf, 96 + inbuflen);
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HMAC_SHA256_Final(hbuf, &hctx);
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memcpy(&outbuf[96 + inbuflen], hbuf, 32);
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/* Zero sensitive data. */
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memset(dk, 0, 64);
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memset(&key_enc_exp, 0, sizeof(AES_KEY));
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/* Success! */
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return (0);
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}
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/**
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* scryptdec_buf(inbuf, inbuflen, outbuf, outlen, passwd, passwdlen,
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* maxmem, maxmemfrac, maxtime):
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* Decrypt inbuflen bytes fro inbuf, writing the result into outbuf and the
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* decrypted data length to outlen. The allocated length of outbuf must
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* be at least inbuflen.
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*/
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int
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scryptdec_buf(const uint8_t * inbuf, size_t inbuflen, uint8_t * outbuf,
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size_t * outlen, const uint8_t * passwd, size_t passwdlen,
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|
size_t maxmem, double maxmemfrac, double maxtime)
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{
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uint8_t hbuf[32];
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uint8_t dk[64];
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uint8_t * key_enc = dk;
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uint8_t * key_hmac = &dk[32];
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int rc;
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HMAC_SHA256_CTX hctx;
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AES_KEY key_enc_exp;
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struct crypto_aesctr * AES;
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/*
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* All versions of the scrypt format will start with "scrypt" and
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* have at least 7 bytes of header.
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*/
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if ((inbuflen < 7) || (memcmp(inbuf, "scrypt", 6) != 0))
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||||||
|
return (7);
|
||||||
|
|
||||||
|
/* Check the format. */
|
||||||
|
if (inbuf[6] != 0)
|
||||||
|
return (8);
|
||||||
|
|
||||||
|
/* We must have at least 128 bytes. */
|
||||||
|
if (inbuflen < 128)
|
||||||
|
return (7);
|
||||||
|
|
||||||
|
/* Parse the header and generate derived keys. */
|
||||||
|
if ((rc = scryptdec_setup(inbuf, dk, passwd, passwdlen,
|
||||||
|
maxmem, maxmemfrac, maxtime)) != 0)
|
||||||
|
return (rc);
|
||||||
|
|
||||||
|
/* Decrypt data. */
|
||||||
|
if (AES_set_encrypt_key(key_enc, 256, &key_enc_exp))
|
||||||
|
return (5);
|
||||||
|
if ((AES = crypto_aesctr_init(&key_enc_exp, 0)) == NULL)
|
||||||
|
return (6);
|
||||||
|
crypto_aesctr_stream(AES, &inbuf[96], outbuf, inbuflen - 128);
|
||||||
|
crypto_aesctr_free(AES);
|
||||||
|
*outlen = inbuflen - 128;
|
||||||
|
|
||||||
|
/* Verify signature. */
|
||||||
|
HMAC_SHA256_Init(&hctx, key_hmac, 32);
|
||||||
|
HMAC_SHA256_Update(&hctx, inbuf, inbuflen - 32);
|
||||||
|
HMAC_SHA256_Final(hbuf, &hctx);
|
||||||
|
if (memcmp(hbuf, &inbuf[inbuflen - 32], 32))
|
||||||
|
return (7);
|
||||||
|
|
||||||
|
/* Zero sensitive data. */
|
||||||
|
memset(dk, 0, 64);
|
||||||
|
memset(&key_enc_exp, 0, sizeof(AES_KEY));
|
||||||
|
|
||||||
|
/* Success! */
|
||||||
|
return (0);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* scryptenc_file(infile, outfile, passwd, passwdlen,
|
||||||
|
* maxmem, maxmemfrac, maxtime):
|
||||||
|
* Read a stream from infile and encrypt it, writing the resulting stream to
|
||||||
|
* outfile.
|
||||||
|
*/
|
||||||
|
int
|
||||||
|
scryptenc_file(FILE * infile, FILE * outfile,
|
||||||
|
const uint8_t * passwd, size_t passwdlen,
|
||||||
|
size_t maxmem, double maxmemfrac, double maxtime)
|
||||||
|
{
|
||||||
|
uint8_t buf[ENCBLOCK];
|
||||||
|
uint8_t dk[64];
|
||||||
|
uint8_t hbuf[32];
|
||||||
|
uint8_t header[96];
|
||||||
|
uint8_t * key_enc = dk;
|
||||||
|
uint8_t * key_hmac = &dk[32];
|
||||||
|
size_t readlen;
|
||||||
|
HMAC_SHA256_CTX hctx;
|
||||||
|
AES_KEY key_enc_exp;
|
||||||
|
struct crypto_aesctr * AES;
|
||||||
|
int rc;
|
||||||
|
|
||||||
|
/* Generate the header and derived key. */
|
||||||
|
if ((rc = scryptenc_setup(header, dk, passwd, passwdlen,
|
||||||
|
maxmem, maxmemfrac, maxtime)) != 0)
|
||||||
|
return (rc);
|
||||||
|
|
||||||
|
/* Hash and write the header. */
|
||||||
|
HMAC_SHA256_Init(&hctx, key_hmac, 32);
|
||||||
|
HMAC_SHA256_Update(&hctx, header, 96);
|
||||||
|
if (fwrite(header, 96, 1, outfile) != 1)
|
||||||
|
return (12);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Read blocks of data, encrypt them, and write them out; hash the
|
||||||
|
* data as it is produced.
|
||||||
|
*/
|
||||||
|
if (AES_set_encrypt_key(key_enc, 256, &key_enc_exp))
|
||||||
|
return (5);
|
||||||
|
if ((AES = crypto_aesctr_init(&key_enc_exp, 0)) == NULL)
|
||||||
|
return (6);
|
||||||
|
do {
|
||||||
|
if ((readlen = fread(buf, 1, ENCBLOCK, infile)) == 0)
|
||||||
|
break;
|
||||||
|
crypto_aesctr_stream(AES, buf, buf, readlen);
|
||||||
|
HMAC_SHA256_Update(&hctx, buf, readlen);
|
||||||
|
if (fwrite(buf, 1, readlen, outfile) < readlen)
|
||||||
|
return (12);
|
||||||
|
} while (1);
|
||||||
|
crypto_aesctr_free(AES);
|
||||||
|
|
||||||
|
/* Did we exit the loop due to a read error? */
|
||||||
|
if (ferror(infile))
|
||||||
|
return (13);
|
||||||
|
|
||||||
|
/* Compute the final HMAC and output it. */
|
||||||
|
HMAC_SHA256_Final(hbuf, &hctx);
|
||||||
|
if (fwrite(hbuf, 32, 1, outfile) != 1)
|
||||||
|
return (12);
|
||||||
|
|
||||||
|
/* Zero sensitive data. */
|
||||||
|
memset(dk, 0, 64);
|
||||||
|
memset(&key_enc_exp, 0, sizeof(AES_KEY));
|
||||||
|
|
||||||
|
/* Success! */
|
||||||
|
return (0);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* scryptdec_file(infile, outfile, passwd, passwdlen,
|
||||||
|
* maxmem, maxmemfrac, maxtime):
|
||||||
|
* Read a stream from infile and decrypt it, writing the resulting stream to
|
||||||
|
* outfile.
|
||||||
|
*/
|
||||||
|
int
|
||||||
|
scryptdec_file(FILE * infile, FILE * outfile,
|
||||||
|
const uint8_t * passwd, size_t passwdlen,
|
||||||
|
size_t maxmem, double maxmemfrac, double maxtime)
|
||||||
|
{
|
||||||
|
uint8_t buf[ENCBLOCK + 32];
|
||||||
|
uint8_t header[96];
|
||||||
|
uint8_t hbuf[32];
|
||||||
|
uint8_t dk[64];
|
||||||
|
uint8_t * key_enc = dk;
|
||||||
|
uint8_t * key_hmac = &dk[32];
|
||||||
|
size_t buflen = 0;
|
||||||
|
size_t readlen;
|
||||||
|
HMAC_SHA256_CTX hctx;
|
||||||
|
AES_KEY key_enc_exp;
|
||||||
|
struct crypto_aesctr * AES;
|
||||||
|
int rc;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Read the first 7 bytes of the file; all future version of scrypt
|
||||||
|
* are guaranteed to have at least 7 bytes of header.
|
||||||
|
*/
|
||||||
|
if (fread(header, 7, 1, infile) < 1) {
|
||||||
|
if (ferror(infile))
|
||||||
|
return (13);
|
||||||
|
else
|
||||||
|
return (7);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Do we have the right magic? */
|
||||||
|
if (memcmp(header, "scrypt", 6))
|
||||||
|
return (7);
|
||||||
|
if (header[6] != 0)
|
||||||
|
return (8);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Read another 89 bytes of the file; version 0 of the srypt file
|
||||||
|
* format has a 96-byte header.
|
||||||
|
*/
|
||||||
|
if (fread(&header[7], 89, 1, infile) < 1) {
|
||||||
|
if (ferror(infile))
|
||||||
|
return (13);
|
||||||
|
else
|
||||||
|
return (7);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Parse the header and generate derived keys. */
|
||||||
|
if ((rc = scryptdec_setup(header, dk, passwd, passwdlen,
|
||||||
|
maxmem, maxmemfrac, maxtime)) != 0)
|
||||||
|
return (rc);
|
||||||
|
|
||||||
|
/* Start hashing with the header. */
|
||||||
|
HMAC_SHA256_Init(&hctx, key_hmac, 32);
|
||||||
|
HMAC_SHA256_Update(&hctx, header, 96);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* We don't know how long the encrypted data block is (we can't know,
|
||||||
|
* since data can be streamed into 'scrypt enc') so we need to read
|
||||||
|
* data and decrypt all of it except the final 32 bytes, then check
|
||||||
|
* if that final 32 bytes is the correct signature.
|
||||||
|
*/
|
||||||
|
if (AES_set_encrypt_key(key_enc, 256, &key_enc_exp))
|
||||||
|
return (5);
|
||||||
|
if ((AES = crypto_aesctr_init(&key_enc_exp, 0)) == NULL)
|
||||||
|
return (6);
|
||||||
|
do {
|
||||||
|
/* Read data until we have more than 32 bytes of it. */
|
||||||
|
if ((readlen = fread(&buf[buflen], 1,
|
||||||
|
ENCBLOCK + 32 - buflen, infile)) == 0)
|
||||||
|
break;
|
||||||
|
buflen += readlen;
|
||||||
|
if (buflen <= 32)
|
||||||
|
continue;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Decrypt, hash, and output everything except the last 32
|
||||||
|
* bytes out of what we have in our buffer.
|
||||||
|
*/
|
||||||
|
HMAC_SHA256_Update(&hctx, buf, buflen - 32);
|
||||||
|
crypto_aesctr_stream(AES, buf, buf, buflen - 32);
|
||||||
|
if (fwrite(buf, 1, buflen - 32, outfile) < buflen - 32)
|
||||||
|
return (12);
|
||||||
|
|
||||||
|
/* Move the last 32 bytes to the start of the buffer. */
|
||||||
|
memmove(buf, &buf[buflen - 32], 32);
|
||||||
|
buflen = 32;
|
||||||
|
} while (1);
|
||||||
|
crypto_aesctr_free(AES);
|
||||||
|
|
||||||
|
/* Did we exit the loop due to a read error? */
|
||||||
|
if (ferror(infile))
|
||||||
|
return (13);
|
||||||
|
|
||||||
|
/* Did we read enough data that we *might* have a valid signature? */
|
||||||
|
if (buflen < 32)
|
||||||
|
return (7);
|
||||||
|
|
||||||
|
/* Verify signature. */
|
||||||
|
HMAC_SHA256_Final(hbuf, &hctx);
|
||||||
|
if (memcmp(hbuf, buf, 32))
|
||||||
|
return (7);
|
||||||
|
|
||||||
|
/* Zero sensitive data. */
|
||||||
|
memset(dk, 0, 64);
|
||||||
|
memset(&key_enc_exp, 0, sizeof(AES_KEY));
|
||||||
|
|
||||||
|
return (0);
|
||||||
|
}
|
||||||
112
lib/genpass/genpass.h
Normal file
112
lib/genpass/genpass.h
Normal file
|
|
@ -0,0 +1,112 @@
|
||||||
|
/*-
|
||||||
|
* Copyright 2009 Colin Percival
|
||||||
|
* All rights reserved.
|
||||||
|
*
|
||||||
|
* Redistribution and use in source and binary forms, with or without
|
||||||
|
* modification, are permitted provided that the following conditions
|
||||||
|
* are met:
|
||||||
|
* 1. Redistributions of source code must retain the above copyright
|
||||||
|
* notice, this list of conditions and the following disclaimer.
|
||||||
|
* 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
* notice, this list of conditions and the following disclaimer in the
|
||||||
|
* documentation and/or other materials provided with the distribution.
|
||||||
|
*
|
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
||||||
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||||
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||||
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||||||
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||||
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||||
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||||
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||||
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||||
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||||
|
* SUCH DAMAGE.
|
||||||
|
*
|
||||||
|
* This file was originally written by Colin Percival as part of the Tarsnap
|
||||||
|
* online backup system.
|
||||||
|
*/
|
||||||
|
#ifndef _SCRYPTENC_H_
|
||||||
|
#define _SCRYPTENC_H_
|
||||||
|
|
||||||
|
#include <stdint.h>
|
||||||
|
#include <stdio.h>
|
||||||
|
|
||||||
|
/**
|
||||||
|
* The parameters maxmem, maxmemfrac, and maxtime used by all of these
|
||||||
|
* functions are defined as follows:
|
||||||
|
* maxmem - maximum number of bytes of storage to use for V array (which is
|
||||||
|
* by far the largest consumer of memory). If this value is set to 0, no
|
||||||
|
* maximum will be enforced; any other value less than 1 MiB will be
|
||||||
|
* treated as 1 MiB.
|
||||||
|
* maxmemfrac - maximum fraction of available storage to use for the V array,
|
||||||
|
* where "available storage" is defined as the minimum out of the
|
||||||
|
* RLIMIT_AS, RLIMIT_DATA. and RLIMIT_RSS resource limits (if any are
|
||||||
|
* set). If this value is set to 0 or more than 0.5 it will be treated
|
||||||
|
* as 0.5; and this value will never cause a limit of less than 1 MiB to
|
||||||
|
* be enforced.
|
||||||
|
* maxtime - maximum amount of CPU time to spend computing the derived keys,
|
||||||
|
* in seconds. This limit is only approximately enforced; the CPU
|
||||||
|
* performance is estimated and parameter limits are chosen accordingly.
|
||||||
|
* For the encryption functions, the parameters to the scrypt key derivation
|
||||||
|
* function are chosen to make the key as strong as possible subject to the
|
||||||
|
* specified limits; for the decryption functions, the parameters used are
|
||||||
|
* compared to the computed limits and an error is returned if decrypting
|
||||||
|
* the data would take too much memory or CPU time.
|
||||||
|
*/
|
||||||
|
/**
|
||||||
|
* Return codes from scrypt(enc|dec)_(buf|file):
|
||||||
|
* 0 success
|
||||||
|
* 1 getrlimit or sysctl(hw.usermem) failed
|
||||||
|
* 2 clock_getres or clock_gettime failed
|
||||||
|
* 3 error computing derived key
|
||||||
|
* 4 could not read salt from /dev/urandom
|
||||||
|
* 5 error in OpenSSL
|
||||||
|
* 6 malloc failed
|
||||||
|
* 7 data is not a valid scrypt-encrypted block
|
||||||
|
* 8 unrecognized scrypt format
|
||||||
|
* 9 decrypting file would take too much memory
|
||||||
|
* 10 decrypting file would take too long
|
||||||
|
* 11 password is incorrect
|
||||||
|
* 12 error writing output file
|
||||||
|
* 13 error reading input file
|
||||||
|
*/
|
||||||
|
|
||||||
|
/**
|
||||||
|
* scryptenc_buf(inbuf, inbuflen, outbuf, passwd, passwdlen,
|
||||||
|
* maxmem, maxmemfrac, maxtime):
|
||||||
|
* Encrypt inbuflen bytes from inbuf, writing the resulting inbuflen + 128
|
||||||
|
* bytes to outbuf.
|
||||||
|
*/
|
||||||
|
int scryptenc_buf(const uint8_t *, size_t, uint8_t *,
|
||||||
|
const uint8_t *, size_t, size_t, double, double);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* scryptdec_buf(inbuf, inbuflen, outbuf, outlen, passwd, passwdlen,
|
||||||
|
* maxmem, maxmemfrac, maxtime):
|
||||||
|
* Decrypt inbuflen bytes from inbuf, writing the result into outbuf and the
|
||||||
|
* decrypted data length to outlen. The allocated length of outbuf must
|
||||||
|
* be at least inbuflen.
|
||||||
|
*/
|
||||||
|
int scryptdec_buf(const uint8_t *, size_t, uint8_t *, size_t *,
|
||||||
|
const uint8_t *, size_t, size_t, double, double);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* scryptenc_file(infile, outfile, passwd, passwdlen,
|
||||||
|
* maxmem, maxmemfrac, maxtime):
|
||||||
|
* Read a stream from infile and encrypt it, writing the resulting stream to
|
||||||
|
* outfile.
|
||||||
|
*/
|
||||||
|
int scryptenc_file(FILE *, FILE *, const uint8_t *, size_t,
|
||||||
|
size_t, double, double);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* scryptdec_file(infile, outfile, passwd, passwdlen,
|
||||||
|
* maxmem, maxmemfrac, maxtime):
|
||||||
|
* Read a stream from infile and decrypt it, writing the resulting stream to
|
||||||
|
* outfile.
|
||||||
|
*/
|
||||||
|
int scryptdec_file(FILE *, FILE *, const uint8_t *, size_t,
|
||||||
|
size_t, double, double);
|
||||||
|
|
||||||
|
#endif /* !_SCRYPTENC_H_ */
|
||||||
Reference in a new issue