diff options
Diffstat (limited to 'tools/plink/sshrand.c')
| -rw-r--r-- | tools/plink/sshrand.c | 246 |
1 files changed, 0 insertions, 246 deletions
diff --git a/tools/plink/sshrand.c b/tools/plink/sshrand.c deleted file mode 100644 index 57ccc1393..000000000 --- a/tools/plink/sshrand.c +++ /dev/null @@ -1,246 +0,0 @@ -/*
- * cryptographic random number generator for PuTTY's ssh client
- */
-
-#include "putty.h"
-#include "ssh.h"
-
-/* Collect environmental noise every 5 minutes */
-#define NOISE_REGULAR_INTERVAL (5*60*TICKSPERSEC)
-
-void noise_get_heavy(void (*func) (void *, int));
-void noise_get_light(void (*func) (void *, int));
-
-/*
- * `pool' itself is a pool of random data which we actually use: we
- * return bytes from `pool', at position `poolpos', until `poolpos'
- * reaches the end of the pool. At this point we generate more
- * random data, by adding noise, stirring well, and resetting
- * `poolpos' to point to just past the beginning of the pool (not
- * _the_ beginning, since otherwise we'd give away the whole
- * contents of our pool, and attackers would just have to guess the
- * next lot of noise).
- *
- * `incomingb' buffers acquired noise data, until it gets full, at
- * which point the acquired noise is SHA'ed into `incoming' and
- * `incomingb' is cleared. The noise in `incoming' is used as part
- * of the noise for each stirring of the pool, in addition to local
- * time, process listings, and other such stuff.
- */
-
-#define HASHINPUT 64 /* 64 bytes SHA input */
-#define HASHSIZE 20 /* 160 bits SHA output */
-#define POOLSIZE 1200 /* size of random pool */
-
-struct RandPool {
- unsigned char pool[POOLSIZE];
- int poolpos;
-
- unsigned char incoming[HASHSIZE];
-
- unsigned char incomingb[HASHINPUT];
- int incomingpos;
-
- int stir_pending;
-};
-
-static struct RandPool pool;
-int random_active = 0;
-long next_noise_collection;
-
-static void random_stir(void)
-{
- word32 block[HASHINPUT / sizeof(word32)];
- word32 digest[HASHSIZE / sizeof(word32)];
- int i, j, k;
-
- /*
- * noise_get_light will call random_add_noise, which may call
- * back to here. Prevent recursive stirs.
- */
- if (pool.stir_pending)
- return;
- pool.stir_pending = TRUE;
-
- noise_get_light(random_add_noise);
-
- SHATransform((word32 *) pool.incoming, (word32 *) pool.incomingb);
- pool.incomingpos = 0;
-
- /*
- * Chunks of this code are blatantly endianness-dependent, but
- * as it's all random bits anyway, WHO CARES?
- */
- memcpy(digest, pool.incoming, sizeof(digest));
-
- /*
- * Make two passes over the pool.
- */
- for (i = 0; i < 2; i++) {
-
- /*
- * We operate SHA in CFB mode, repeatedly adding the same
- * block of data to the digest. But we're also fiddling
- * with the digest-so-far, so this shouldn't be Bad or
- * anything.
- */
- memcpy(block, pool.pool, sizeof(block));
-
- /*
- * Each pass processes the pool backwards in blocks of
- * HASHSIZE, just so that in general we get the output of
- * SHA before the corresponding input, in the hope that
- * things will be that much less predictable that way
- * round, when we subsequently return bytes ...
- */
- for (j = POOLSIZE; (j -= HASHSIZE) >= 0;) {
- /*
- * XOR the bit of the pool we're processing into the
- * digest.
- */
-
- for (k = 0; k < sizeof(digest) / sizeof(*digest); k++)
- digest[k] ^= ((word32 *) (pool.pool + j))[k];
-
- /*
- * Munge our unrevealed first block of the pool into
- * it.
- */
- SHATransform(digest, block);
-
- /*
- * Stick the result back into the pool.
- */
-
- for (k = 0; k < sizeof(digest) / sizeof(*digest); k++)
- ((word32 *) (pool.pool + j))[k] = digest[k];
- }
- }
-
- /*
- * Might as well save this value back into `incoming', just so
- * there'll be some extra bizarreness there.
- */
- SHATransform(digest, block);
- memcpy(pool.incoming, digest, sizeof(digest));
-
- pool.poolpos = sizeof(pool.incoming);
-
- pool.stir_pending = FALSE;
-}
-
-void random_add_noise(void *noise, int length)
-{
- unsigned char *p = noise;
- int i;
-
- if (!random_active)
- return;
-
- /*
- * This function processes HASHINPUT bytes into only HASHSIZE
- * bytes, so _if_ we were getting incredibly high entropy
- * sources then we would be throwing away valuable stuff.
- */
- while (length >= (HASHINPUT - pool.incomingpos)) {
- memcpy(pool.incomingb + pool.incomingpos, p,
- HASHINPUT - pool.incomingpos);
- p += HASHINPUT - pool.incomingpos;
- length -= HASHINPUT - pool.incomingpos;
- SHATransform((word32 *) pool.incoming, (word32 *) pool.incomingb);
- for (i = 0; i < HASHSIZE; i++) {
- pool.pool[pool.poolpos++] ^= pool.incomingb[i];
- if (pool.poolpos >= POOLSIZE)
- pool.poolpos = 0;
- }
- if (pool.poolpos < HASHSIZE)
- random_stir();
-
- pool.incomingpos = 0;
- }
-
- memcpy(pool.incomingb + pool.incomingpos, p, length);
- pool.incomingpos += length;
-}
-
-void random_add_heavynoise(void *noise, int length)
-{
- unsigned char *p = noise;
- int i;
-
- while (length >= POOLSIZE) {
- for (i = 0; i < POOLSIZE; i++)
- pool.pool[i] ^= *p++;
- random_stir();
- length -= POOLSIZE;
- }
-
- for (i = 0; i < length; i++)
- pool.pool[i] ^= *p++;
- random_stir();
-}
-
-static void random_add_heavynoise_bitbybit(void *noise, int length)
-{
- unsigned char *p = noise;
- int i;
-
- while (length >= POOLSIZE - pool.poolpos) {
- for (i = 0; i < POOLSIZE - pool.poolpos; i++)
- pool.pool[pool.poolpos + i] ^= *p++;
- random_stir();
- length -= POOLSIZE - pool.poolpos;
- pool.poolpos = 0;
- }
-
- for (i = 0; i < length; i++)
- pool.pool[i] ^= *p++;
- pool.poolpos = i;
-}
-
-static void random_timer(void *ctx, long now)
-{
- if (random_active > 0 && now - next_noise_collection >= 0) {
- noise_regular();
- next_noise_collection =
- schedule_timer(NOISE_REGULAR_INTERVAL, random_timer, &pool);
- }
-}
-
-void random_ref(void)
-{
- if (!random_active) {
- memset(&pool, 0, sizeof(pool)); /* just to start with */
-
- noise_get_heavy(random_add_heavynoise_bitbybit);
- random_stir();
-
- next_noise_collection =
- schedule_timer(NOISE_REGULAR_INTERVAL, random_timer, &pool);
- }
-
- random_active++;
-}
-
-void random_unref(void)
-{
- random_active--;
-}
-
-int random_byte(void)
-{
- if (pool.poolpos >= POOLSIZE)
- random_stir();
-
- return pool.pool[pool.poolpos++];
-}
-
-void random_get_savedata(void **data, int *len)
-{
- void *buf = snewn(POOLSIZE / 2, char);
- random_stir();
- memcpy(buf, pool.pool + pool.poolpos, POOLSIZE / 2);
- *len = POOLSIZE / 2;
- *data = buf;
- random_stir();
-}
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