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Diffstat (limited to 'src/libfreeswan/prng.c')
| -rw-r--r-- | src/libfreeswan/prng.c | 200 |
1 files changed, 0 insertions, 200 deletions
diff --git a/src/libfreeswan/prng.c b/src/libfreeswan/prng.c deleted file mode 100644 index 347f13f89..000000000 --- a/src/libfreeswan/prng.c +++ /dev/null @@ -1,200 +0,0 @@ -/* - * crypto-class pseudorandom number generator - * currently uses same algorithm as RC4(TM), from Schneier 2nd ed p397 - * Copyright (C) 2002 Henry Spencer. - * - * This library is free software; you can redistribute it and/or modify it - * under the terms of the GNU Library General Public License as published by - * the Free Software Foundation; either version 2 of the License, or (at your - * option) any later version. See <http://www.fsf.org/copyleft/lgpl.txt>. - * - * This library 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 Library General Public - * License for more details. - */ -#include "internal.h" -#include "freeswan.h" - -/* - - prng_init - initialize PRNG from a key - */ -void -prng_init(prng, key, keylen) -struct prng *prng; -const unsigned char *key; -size_t keylen; -{ - unsigned char k[256]; - int i, j; - unsigned const char *p; - unsigned const char *keyend = key + keylen; - unsigned char t; - - for (i = 0; i <= 255; i++) - prng->sbox[i] = i; - p = key; - for (i = 0; i <= 255; i++) { - k[i] = *p++; - if (p >= keyend) - p = key; - } - j = 0; - for (i = 0; i <= 255; i++) { - j = (j + prng->sbox[i] + k[i]) & 0xff; - t = prng->sbox[i]; - prng->sbox[i] = prng->sbox[j]; - prng->sbox[j] = t; - k[i] = 0; /* clear out key memory */ - } - prng->i = 0; - prng->j = 0; - prng->count = 0; -} - -/* - - prng_bytes - get some pseudorandom bytes from PRNG - */ -void -prng_bytes(prng, dst, dstlen) -struct prng *prng; -unsigned char *dst; -size_t dstlen; -{ - int i, j, t; - unsigned char *p = dst; - size_t remain = dstlen; -# define MAX 4000000000ul - - while (remain > 0) { - i = (prng->i + 1) & 0xff; - prng->i = i; - j = (prng->j + prng->sbox[i]) & 0xff; - prng->j = j; - t = prng->sbox[i]; - prng->sbox[i] = prng->sbox[j]; - prng->sbox[j] = t; - t = (t + prng->sbox[i]) & 0xff; - *p++ = prng->sbox[t]; - remain--; - } - if (prng->count < MAX - dstlen) - prng->count += dstlen; - else - prng->count = MAX; -} - -/* - - prnt_count - how many bytes have been extracted from PRNG so far? - */ -unsigned long -prng_count(prng) -struct prng *prng; -{ - return prng->count; -} - -/* - - prng_final - clear out PRNG to ensure nothing left in memory - */ -void -prng_final(prng) -struct prng *prng; -{ - int i; - - for (i = 0; i <= 255; i++) - prng->sbox[i] = 0; - prng->i = 0; - prng->j = 0; - prng->count = 0; /* just for good measure */ -} - - - -#ifdef PRNG_MAIN - -#include <stdio.h> - -void regress(); - -int -main(argc, argv) -int argc; -char *argv[]; -{ - struct prng pr; - unsigned char buf[100]; - unsigned char *p; - size_t n; - - if (argc < 2) { - fprintf(stderr, "Usage: %s {key|-r}\n", argv[0]); - exit(2); - } - - if (strcmp(argv[1], "-r") == 0) { - regress(); - fprintf(stderr, "regress() returned?!?\n"); - exit(1); - } - - prng_init(&pr, argv[1], strlen(argv[1])); - prng_bytes(&pr, buf, 32); - printf("0x"); - for (p = buf, n = 32; n > 0; p++, n--) - printf("%02x", *p); - printf("\n%lu bytes\n", prng_count(&pr)); - prng_final(&pr); - exit(0); -} - -void -regress() -{ - struct prng pr; - unsigned char buf[100]; - unsigned char *p; - size_t n; - /* somewhat non-random sample key */ - unsigned char key[] = "here we go gathering nuts in May"; - /* first thirty bytes of output from that key */ - unsigned char good[] = "\x3f\x02\x8e\x4a\x2a\xea\x23\x18\x92\x7c" - "\x09\x52\x83\x61\xaa\x26\xce\xbb\x9d\x71" - "\x71\xe5\x10\x22\xaf\x60\x54\x8d\x5b\x28"; - int nzero, none; - int show = 0; - - prng_init(&pr, key, strlen(key)); - prng_bytes(&pr, buf, sizeof(buf)); - for (p = buf, n = sizeof(buf); n > 0; p++, n--) { - if (*p == 0) - nzero++; - if (*p == 255) - none++; - } - if (nzero > 3 || none > 3) { - fprintf(stderr, "suspiciously non-random output!\n"); - show = 1; - } - if (memcmp(buf, good, strlen(good)) != 0) { - fprintf(stderr, "incorrect output!\n"); - show = 1; - } - if (show) { - fprintf(stderr, "0x"); - for (p = buf, n = sizeof(buf); n > 0; p++, n--) - fprintf(stderr, "%02x", *p); - fprintf(stderr, "\n"); - exit(1); - } - if (prng_count(&pr) != sizeof(buf)) { - fprintf(stderr, "got %u bytes, but count is %lu\n", - sizeof(buf), prng_count(&pr)); - exit(1); - } - prng_final(&pr); - exit(0); -} - -#endif /* PRNG_MAIN */ |