Re: [PROPOSAL/PATCH] Fortuna PRNG in /dev/random

[Jean-Luc Cooke]

On Fri, Sep 24, 2004 at 12:38:51AM -0400, Theodore Ts'o wrote:
> I'm also a bit concerned about how much time AES takes over the
> cut-down MD4, as this may affect networking benchmarks.  (And we don't
> need super-strength crypto here.)

Oh,

openssl speed md4 aes shows:

type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
md4              10708.72k    38240.96k   111170.47k   215872.85k 296828.93k
aes-128 cbc      32121.81k    32678.31k    33119.49k    33221.29k 33210.59k
aes-192 cbc      27915.92k    27868.52k    28418.08k    28677.12k 28721.15k
aes-256 cbc      24599.57k    25142.38k    25381.80k    25474.88k 25392.46k

Since we're using small blocks.

Attached is the patch with the problems Ted pointed out.

JLC
diff -uNr linux-2.6.8.1-orig/include/linux/sysctl.h linux-2.6.8.1-fortuna/include/linux/sysctl.h
--- linux-2.6.8.1-orig/include/linux/sysctl.h	2004-08-14 12:55:33.000000000 +0200
+++ linux-2.6.8.1-fortuna/include/linux/sysctl.h	2004-09-13 18:55:43.000000000 +0200
@@ -198,7 +198,8 @@
 	RANDOM_READ_THRESH=3,
 	RANDOM_WRITE_THRESH=4,
 	RANDOM_BOOT_ID=5,
-	RANDOM_UUID=6
+	RANDOM_UUID=6,
+	RANDOM_DERIVE_SEED=7
 };
 
 /* /proc/sys/kernel/pty */
--- linux-2.6.8.1/drivers/char/random.c	2004-09-24 08:32:30.222610504 -0400
+++ linux-2.6.8.1-rand2/drivers/char/random.c	2004-09-24 09:31:30.251444320 -0400
@@ -2,9 +2,11 @@
  * random.c -- A strong random number generator
  *
  * Version 1.89, last modified 19-Sep-99
+ * Version 2.01, last modified 24-Sep-2004
  * 
  * Copyright Theodore Ts'o, 1994, 1995, 1996, 1997, 1998, 1999.  All
  * rights reserved.
+ * Copyright Jean-Luc Cooke, 2004.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -40,61 +42,157 @@
  */
 
 /*
- * (now, with legal B.S. out of the way.....) 
- * 
- * This routine gathers environmental noise from device drivers, etc.,
- * and returns good random numbers, suitable for cryptographic use.
- * Besides the obvious cryptographic uses, these numbers are also good
- * for seeding TCP sequence numbers, and other places where it is
- * desirable to have numbers which are not only random, but hard to
- * predict by an attacker.
- *
- * Theory of operation
- * ===================
- * 
- * Computers are very predictable devices.  Hence it is extremely hard
- * to produce truly random numbers on a computer --- as opposed to
- * pseudo-random numbers, which can easily generated by using a
- * algorithm.  Unfortunately, it is very easy for attackers to guess
- * the sequence of pseudo-random number generators, and for some
- * applications this is not acceptable.  So instead, we must try to
- * gather "environmental noise" from the computer's environment, which
- * must be hard for outside attackers to observe, and use that to
- * generate random numbers.  In a Unix environment, this is best done
- * from inside the kernel.
- * 
- * Sources of randomness from the environment include inter-keyboard
- * timings, inter-interrupt timings from some interrupts, and other
- * events which are both (a) non-deterministic and (b) hard for an
- * outside observer to measure.  Randomness from these sources are
- * added to an "entropy pool", which is mixed using a CRC-like function.
- * This is not cryptographically strong, but it is adequate assuming
- * the randomness is not chosen maliciously, and it is fast enough that
- * the overhead of doing it on every interrupt is very reasonable.
- * As random bytes are mixed into the entropy pool, the routines keep
- * an *estimate* of how many bits of randomness have been stored into
- * the random number generator's internal state.
- * 
- * When random bytes are desired, they are obtained by taking the SHA
- * hash of the contents of the "entropy pool".  The SHA hash avoids
- * exposing the internal state of the entropy pool.  It is believed to
- * be computationally infeasible to derive any useful information
- * about the input of SHA from its output.  Even if it is possible to
- * analyze SHA in some clever way, as long as the amount of data
- * returned from the generator is less than the inherent entropy in
- * the pool, the output data is totally unpredictable.  For this
- * reason, the routine decreases its internal estimate of how many
- * bits of "true randomness" are contained in the entropy pool as it
- * outputs random numbers.
- * 
- * If this estimate goes to zero, the routine can still generate
- * random numbers; however, an attacker may (at least in theory) be
- * able to infer the future output of the generator from prior
- * outputs.  This requires successful cryptanalysis of SHA, which is
- * not believed to be feasible, but there is a remote possibility.
- * Nonetheless, these numbers should be useful for the vast majority
- * of purposes.
- * 
+ * The entire PRNG used in this file was replaced using a variant of the Fortuna
+ * PRNG described in Practical Cryptography by Ferguson and Schnier.
+ *
+ * The changes to their design include:
+ *  - feeding the output of each pool back into their input to carry entropy
+ *    forward (avoids pool overflow attacks like
+ *    "dd if=/dev/zero of=/dev/random"
+ *
+ * Also, the entropy estimator was removed since it is not needed for
+ * cryptographically secure random data and such constructions are
+ * historically prone to attack
+ * [read Practical Cryptography].
+ *
+ * The Fortuna PRNG as described in Practical Cryptography is implemented here.
+ * 
+ * Pseudo-code follows.
+ *
+<b>create_entropy_pool(r)</b>
+ - create an entropy pool in "r"
+
+  r.pool0_len = 0;
+  r.reseed_count = 0;
+  r.derive_count = 0;
+  r.digestsize = // digest size for our hash
+  r.blocksize = // block size for our cipher
+  r.keysize = // key size for our cipher
+  for (i=0; i&lt;32; i++) {
+    crypto_digest_init(r.pool[i]);
+  }
+  memset(r.key, 0, r.keysize);
+  crypto_cipher_setkey(r.cipher, r.key, r.keysize);
+
+<b>add_entropy_words(r, in, nwords)</b>
+ - mix 32bit word array "in" which is "nwords" long into pool "r"
+
+  crypto_digest_update(r.pool[i], in, nwords*sizeof(in[0]));
+  if (r.pool_index == 0)
+    r.pool0_len += nwords*sizeof(in[0]);
+  r.pool_index = r.pool_index + 1  mod  (2<sup>number of pools</sup> - 1)
+  
+<b>random_reseed(r)</b>
+ - reseed the key from the pooling system
+
+  r.reseed_count++;
+  
+  crypto_digest_init(hash);
+  crypto_digest_update(hash, r.key, r.keysize);
+  
+  for (i=0; i&lt;32; i++) {
+    if (2<sup>i</sup> is a factor of r.reseed_count) {
+      crypto_digest_final(r.pool[i], tmp);
+      crypto_digest_init(r.poo[i]);
+      crypto_digest_update(hash, tmp, r.digestsize);
+  
+      // jlcooke: small change from Ferguson
+      crypto_digest_update(r.pool[i], tmp, r.digestsize);
+    }
+  }
+  
+  crypto_digest_final(hash, tmp);
+  crypto_cipher_setkey(r.cipher, tmp, r.keysize);
+  r.ctrValue = r.ctrValue + 1  mod  (2<sup>number of pools</sup> - 1)
+
+<b>extract_entropy(r, buf, nbytes, flags)</b>
+ - fill byte array "buf" with "nbytes" of random data from entropy pool "r"
+
+  random_reseed(r);
+  r.pool0_len = 0;
+  
+  while (nbytes &gt; 0) {
+    crypto_cipher_encrypt(r.cipher, tmp, r.ctrValue, r.blocksize);
+    r.ctrValue++; // modulo 2<sup>r.blocksize/8</sup> 
+  
+    //
+    // Copy r.blocksize of tmp to the user
+    // Unless nbytes is less than r.blocksize, in which case only copy nbytes
+    //  
+  
+    nbytes -= r.blocksize;
+  }
+  
+  // generate a new key
+  crypto_cipher_encrypt(r.cipher, r.key, r.ctrValue, r.blocksize);
+  crypto_cipher_setkey(r.cipher, r.key, r.keysize);
+  
+<b>derive_pool(r, buf)</b>
+ - Fill "buf" with the output from a 1-way transformation of all 32-pools
+
+  memset(tmp, 0, r.digestsize);
+  r.pool0_len = 0;
+  
+  for (i=0; i&lt;32; i++) {
+    crypto_digest_init(hash);
+  
+    crypto_digest_update(hash, tmp, r.digestsize);
+  
+    crypto_digest_final(r.pool[i], tmp);
+    crypto_digest_init(r.pool[i]);
+    crypto_digest_update(hash, tmp, r.digestsize);
+  
+    crypto_digest_update(hash, r.derive_count, sizeof(r.derive_count));
+  
+    crypto_digest_final(hash, tmp);
+  
+    // Replace all 0x00 in "tmp" with "0x01" because the API to return a byte
+    //  array does not exist.  Only a "return string" API is provided.  This
+    //  reduces the effective entropy of the output by 0.39%.
+    // 
+  
+    memcpy(&amp;buf[i*r.digestsize], tmp, r.digestsize);
+    r.derive_count++;
+  }
+ *
+ * Draft Security Statement/Analysis (Jean-Luc Cooke <jlcooke@xxxxxxxxxxxxxx>)
+ *
+ * The Fortuna PRNG is resilliant to all known and preventable PRNG attacks.
+ * Proof of strength to these attacks can be done by reduction to the security
+ * of the underlying cryptographic primitives.
+ *  * H = HASH(M)
+ *   + M={0,1}^Mlen  0 <= Mlen < infinity
+ *   + H={0,1}^Hlen  256 <= Hlen 
+ *  * C = ENCRYPT(K,M)
+ *   + K={0,1}^Klen  256 <= Klen
+ *   + M={0,1}^Mlen  Mlen = 128
+ *   + C={0,1}^Clen  Clen = 128
+ *
+ *  - Invertability of the output function
+ *    The state of the output function Output[i] = ENCRYPT(KEY, CTR++) is
+ *    {KEY,CTR}  To recover the state {KEY,CTR} the attacker must be able to
+ *    mount a known-plaintext or a known-ciphertext attack on the block cipher
+ *    C=ENCRYPT(K,M) with N blocks.
+ *    N = ReseedIntervalInSeconds * OutputRateInBytesPerSecond / BytesPerBlock
+ *    AES256 in CTR is secure from known-plaintext/ciphertext key recovery
+ *    attacks with N < 2^128
+ *    However, After 2^64 blocks (2^71 bits) an attacker would have a 0.5 chance
+ *    to guessing the next 128bit output.  N <<< 2^64
+ *
+ *  - Invertability of the pool mixing function
+ *    The pool mixing function H' = HASH(H' || M) is said to be non-inveretable
+ *    if H=HASH(MSG) is invertable.
+ *    There have been no invertability discoveries in SHA-256.
+ * 
+ *  - Manipulating pool mixing
+ *    An attack who has access to one or all of the entropy event sources may
+ *    be able to input mallicious event data to alter any one of the pool states
+ *    into a degenerate state.  This requires that the underlying H=HASH(MSG)
+ *    function is suseptible to a 1st pre-image attack.  SHA-256 has no such
+ *    known attacks.
+ */
+
+/*
  * Exported interfaces ---- output
  * ===============================
  * 
@@ -107,17 +205,13 @@
  * and place it in the requested buffer.
  * 
  * The two other interfaces are two character devices /dev/random and
- * /dev/urandom.  /dev/random is suitable for use when very high
- * quality randomness is desired (for example, for key generation or
- * one-time pads), as it will only return a maximum of the number of
- * bits of randomness (as estimated by the random number generator)
- * contained in the entropy pool.
- * 
- * The /dev/urandom device does not have this limit, and will return
- * as many bytes as are requested.  As more and more random bytes are
- * requested without giving time for the entropy pool to recharge,
- * this will result in random numbers that are merely cryptographically
- * strong.  For many applications, however, this is acceptable.
+ * /dev/urandom.  They are synonymous with eachother for legacy reasons
+ * 
+ * Both the devices will return as many bytes as are requested.  As more
+ * and more random bytes are requested without giving time for the entropy
+ * pool to recharge, this will result in random numbers that are merely
+ * cryptographically strong.  For many applications, however, this is
+ * acceptable.
  *
  * Exported interfaces ---- input
  * ==============================
@@ -160,32 +254,28 @@
  * following lines an appropriate script which is run during the boot
  * sequence: 
  *
- *	echo "Initializing random number generator..."
- *	random_seed=/var/run/random-seed
- *	# Carry a random seed from start-up to start-up
- *	# Load and then save the whole entropy pool
- *	if [ -f $random_seed ]; then
- *		cat $random_seed >/dev/urandom
- *	else
- *		touch $random_seed
- *	fi
- *	chmod 600 $random_seed
- *	poolfile=/proc/sys/kernel/random/poolsize
- *	[ -r $poolfile ] && bytes=`cat $poolfile` || bytes=512
- *	dd if=/dev/urandom of=$random_seed count=1 bs=$bytes
+ *      echo "Initializing random number generator..."
+ *      random_seed=/var/run/random-seed
+ *      # Carry a random seed from start-up to start-up
+ *      # Load and then save the whole entropy pool
+ *      if [ -f $random_seed ]; then
+ *              cat $random_seed >/dev/urandom
+ *      else
+ *              touch $random_seed
+ *      fi
+ *      chmod 600 $random_seed
+ *      dd if=/proc/sys/kernel/random/derive_seed of=$random_seed
  *
  * and the following lines in an appropriate script which is run as
  * the system is shutdown:
  *
- *	# Carry a random seed from shut-down to start-up
- *	# Save the whole entropy pool
- *	echo "Saving random seed..."
- *	random_seed=/var/run/random-seed
- *	touch $random_seed
- *	chmod 600 $random_seed
- *	poolfile=/proc/sys/kernel/random/poolsize
- *	[ -r $poolfile ] && bytes=`cat $poolfile` || bytes=512
- *	dd if=/dev/urandom of=$random_seed count=1 bs=$bytes
+ *      # Carry a random seed from shut-down to start-up
+ *      # Save the whole entropy pool
+ *      echo "Saving random seed..."
+ *      random_seed=/var/run/random-seed
+ *      touch $random_seed
+ *      chmod 600 $random_seed
+ *      dd if=/proc/sys/kernel/random/derive_seed of=$random_seed
  *
  * For example, on most modern systems using the System V init
  * scripts, such code fragments would be found in
@@ -215,22 +305,11 @@
  * Acknowledgements:
  * =================
  *
- * Ideas for constructing this random number generator were derived
- * from Pretty Good Privacy's random number generator, and from private
- * discussions with Phil Karn.  Colin Plumb provided a faster random
- * number generator, which speed up the mixing function of the entropy
- * pool, taken from PGPfone.  Dale Worley has also contributed many
- * useful ideas and suggestions to improve this driver.
+ * The design for this RNG come from Fortuna as explined above.
+ * Cryptographic implementations are used from the CryptoAPI.
  * 
  * Any flaws in the design are solely my responsibility, and should
- * not be attributed to the Phil, Colin, or any of authors of PGP.
- * 
- * The code for SHA transform was taken from Peter Gutmann's
- * implementation, which has been placed in the public domain.
- * The code for MD5 transform was taken from Colin Plumb's
- * implementation, which has been placed in the public domain.
- * The MD5 cryptographic checksum was devised by Ronald Rivest, and is
- * documented in RFC 1321, "The MD5 Message Digest Algorithm".
+ * not be attributed to the Ted, Phil, Colin, or any of authors of PGP.
  * 
  * Further background information on this topic may be obtained from
  * RFC 1750, "Randomness Recommendations for Security", by Donald
@@ -254,137 +333,43 @@
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <linux/percpu.h>
+#include <linux/crypto.h>
+#include <../crypto/internal.h>
 
+#include <asm/scatterlist.h>
 #include <asm/processor.h>
 #include <asm/uaccess.h>
 #include <asm/irq.h>
 #include <asm/io.h>
 
-/*
- * Configuration information
- */
-#define DEFAULT_POOL_SIZE 512
-#define SECONDARY_POOL_SIZE 128
-#define BATCH_ENTROPY_SIZE 256
-#define USE_SHA
-
-/*
- * The minimum number of bits of entropy before we wake up a read on
- * /dev/random.  Should be enough to do a significant reseed.
- */
-static int random_read_wakeup_thresh = 64;
-
-/*
- * If the entropy count falls under this number of bits, then we
- * should wake up processes which are selecting or polling on write
- * access to /dev/random.
- */
-static int random_write_wakeup_thresh = 128;
-
-/*
- * When the input pool goes over trickle_thresh, start dropping most
- * samples to avoid wasting CPU time and reduce lock contention.
- */
-
-static int trickle_thresh = DEFAULT_POOL_SIZE * 7;
-
-static DEFINE_PER_CPU(int, trickle_count) = 0;
+#if 0
+	#define DEBUG_PRINTK  printk
+#else
+	#define DEBUG_PRINTK  debug_printk
+static inline void debug_printk(const char *a, ...) {}
+#endif
 
 /*
- * A pool of size .poolwords is stirred with a primitive polynomial
- * of degree .poolwords over GF(2).  The taps for various sizes are
- * defined below.  They are chosen to be evenly spaced (minimum RMS
- * distance from evenly spaced; the numbers in the comments are a
- * scaled squared error sum) except for the last tap, which is 1 to
- * get the twisting happening as fast as possible.
+ * Configuration information
  */
-static struct poolinfo {
-	int	poolwords;
-	int	tap1, tap2, tap3, tap4, tap5;
-} poolinfo_table[] = {
-	/* x^2048 + x^1638 + x^1231 + x^819 + x^411 + x + 1  -- 115 */
-	{ 2048,	1638,	1231,	819,	411,	1 },
-
-	/* x^1024 + x^817 + x^615 + x^412 + x^204 + x + 1 -- 290 */
-	{ 1024,	817,	615,	412,	204,	1 },
-#if 0				/* Alternate polynomial */
-	/* x^1024 + x^819 + x^616 + x^410 + x^207 + x^2 + 1 -- 115 */
-	{ 1024,	819,	616,	410,	207,	2 },
-#endif
-
-	/* x^512 + x^411 + x^308 + x^208 + x^104 + x + 1 -- 225 */
-	{ 512,	411,	308,	208,	104,	1 },
-#if 0				/* Alternates */
-	/* x^512 + x^409 + x^307 + x^206 + x^102 + x^2 + 1 -- 95 */
-	{ 512,	409,	307,	206,	102,	2 },
-	/* x^512 + x^409 + x^309 + x^205 + x^103 + x^2 + 1 -- 95 */
-	{ 512,	409,	309,	205,	103,	2 },
-#endif
-
-	/* x^256 + x^205 + x^155 + x^101 + x^52 + x + 1 -- 125 */
-	{ 256,	205,	155,	101,	52,	1 },
-
-	/* x^128 + x^103 + x^76 + x^51 +x^25 + x + 1 -- 105 */
-	{ 128,	103,	76,	51,	25,	1 },
-#if 0	/* Alternate polynomial */
-	/* x^128 + x^103 + x^78 + x^51 + x^27 + x^2 + 1 -- 70 */
-	{ 128,	103,	78,	51,	27,	2 },
-#endif
-
-	/* x^64 + x^52 + x^39 + x^26 + x^14 + x + 1 -- 15 */
-	{ 64,	52,	39,	26,	14,	1 },
-
-	/* x^32 + x^26 + x^20 + x^14 + x^7 + x + 1 -- 15 */
-	{ 32,	26,	20,	14,	7,	1 },
-
-	{ 0,	0,	0,	0,	0,	0 },
-};
-
-#define POOLBITS	poolwords*32
-#define POOLBYTES	poolwords*4
+#define BATCH_ENTROPY_SIZE 512 /* how many events do we buffer?  BATCH_ENTROPY_SIZE/2 == how many we need before batch-submitting them */
+#define RANDOM_RESEED_INTERVAL 600 /* reseed the PRNG output state every 5mins */
+#define RANDOM_DEFAULT_CIPHER_ALGO "aes"
+#define RANDOM_DEFAULT_DIGEST_ALGO "sha256"
+
+#define DEFAULT_POOL_NUMBER 5 /* 2^{5} = 32 pools */
+#define MAXIMUM_POOL_NUMBER DEFAULT_POOL_NUMBER
+#define MINIMUM_POOL_NUMBER 2 /* 2^{2} = 4 pools */
+#define USE_SHA256
+#define RANDOM_MAX_DIGEST_SIZE 64 /* SHA512/WHIRLPOOL have 64bytes == 512 bits */
+#define RANDOM_MAX_BLOCK_SIZE  16 /* AES256 has 16byte blocks == 128 bits */
+#define RANDOM_MAX_KEY_SIZE    32 /* AES256 has 32byte keys == 256 bits */
+#define USE_AES256
 
 /*
- * For the purposes of better mixing, we use the CRC-32 polynomial as
- * well to make a twisted Generalized Feedback Shift Reigster
- *
- * (See M. Matsumoto & Y. Kurita, 1992.  Twisted GFSR generators.  ACM
- * Transactions on Modeling and Computer Simulation 2(3):179-194.
- * Also see M. Matsumoto & Y. Kurita, 1994.  Twisted GFSR generators
- * II.  ACM Transactions on Mdeling and Computer Simulation 4:254-266)
- *
- * Thanks to Colin Plumb for suggesting this.
- * 
- * We have not analyzed the resultant polynomial to prove it primitive;
- * in fact it almost certainly isn't.  Nonetheless, the irreducible factors
- * of a random large-degree polynomial over GF(2) are more than large enough
- * that periodicity is not a concern.
- * 
- * The input hash is much less sensitive than the output hash.  All
- * that we want of it is that it be a good non-cryptographic hash;
- * i.e. it not produce collisions when fed "random" data of the sort
- * we expect to see.  As long as the pool state differs for different
- * inputs, we have preserved the input entropy and done a good job.
- * The fact that an intelligent attacker can construct inputs that
- * will produce controlled alterations to the pool's state is not
- * important because we don't consider such inputs to contribute any
- * randomness.  The only property we need with respect to them is that
- * the attacker can't increase his/her knowledge of the pool's state.
- * Since all additions are reversible (knowing the final state and the
- * input, you can reconstruct the initial state), if an attacker has
- * any uncertainty about the initial state, he/she can only shuffle
- * that uncertainty about, but never cause any collisions (which would
- * decrease the uncertainty).
- *
- * The chosen system lets the state of the pool be (essentially) the input
- * modulo the generator polymnomial.  Now, for random primitive polynomials,
- * this is a universal class of hash functions, meaning that the chance
- * of a collision is limited by the attacker's knowledge of the generator
- * polynomail, so if it is chosen at random, an attacker can never force
- * a collision.  Here, we use a fixed polynomial, but we *can* assume that
- * ###--> it is unknown to the processes generating the input entropy. <-###
- * Because of this important property, this is a good, collision-resistant
- * hash; hash collisions will occur no more often than chance.
+ * Throttle mouse/keyboard/disk/interrupt entropy input to only add after this many jiffies/rdtsc counts
  */
+#define RANDOM_INPUT_THROTTLE  1000
 
 /*
  * Linux 2.2 compatibility
@@ -399,8 +384,10 @@
 /*
  * Static global variables
  */
+static int random_entropy_count; // jlc & cam have been together for 5 and 2/3 years as of the time this was written;
+static int random_read_wakeup_thresh = 0; // ignored now.
+static int random_write_wakeup_thresh = 0; // ignored now.
 static struct entropy_store *random_state; /* The default global store */
-static struct entropy_store *sec_random_state; /* secondary store */
 static DECLARE_WAIT_QUEUE_HEAD(random_read_wait);
 static DECLARE_WAIT_QUEUE_HEAD(random_write_wait);
 
@@ -411,71 +398,6 @@
 static void sysctl_init_random(struct entropy_store *random_state);
 #endif
 
-/*****************************************************************
- *
- * Utility functions, with some ASM defined functions for speed
- * purposes
- * 
- *****************************************************************/
-
-/*
- * Unfortunately, while the GCC optimizer for the i386 understands how
- * to optimize a static rotate left of x bits, it doesn't know how to
- * deal with a variable rotate of x bits.  So we use a bit of asm magic.
- */
-#if (!defined (__i386__))
-static inline __u32 rotate_left(int i, __u32 word)
-{
-	return (word << i) | (word >> (32 - i));
-	
-}
-#else
-static inline __u32 rotate_left(int i, __u32 word)
-{
-	__asm__("roll %%cl,%0"
-		:"=r" (word)
-		:"0" (word),"c" (i));
-	return word;
-}
-#endif
-
-/*
- * More asm magic....
- * 
- * For entropy estimation, we need to do an integral base 2
- * logarithm.  
- *
- * Note the "12bits" suffix - this is used for numbers between
- * 0 and 4095 only.  This allows a few shortcuts.
- */
-#if 0	/* Slow but clear version */
-static inline __u32 int_ln_12bits(__u32 word)
-{
-	__u32 nbits = 0;
-	
-	while (word >>= 1)
-		nbits++;
-	return nbits;
-}
-#else	/* Faster (more clever) version, courtesy Colin Plumb */
-static inline __u32 int_ln_12bits(__u32 word)
-{
-	/* Smear msbit right to make an n-bit mask */
-	word |= word >> 8;
-	word |= word >> 4;
-	word |= word >> 2;
-	word |= word >> 1;
-	/* Remove one bit to make this a logarithm */
-	word >>= 1;
-	/* Count the bits set in the word */
-	word -= (word >> 1) & 0x555;
-	word = (word & 0x333) + ((word >> 2) & 0x333);
-	word += (word >> 4);
-	word += (word >> 8);
-	return word & 15;
-}
-#endif
-
 #if 0
 #define DEBUG_ENT(fmt, arg...) printk(KERN_DEBUG "random: " fmt, ## arg)
 #else
@@ -490,15 +412,28 @@
  **********************************************************************/
 
 struct entropy_store {
-	/* mostly-read data: */
-	struct poolinfo poolinfo;
-	__u32		*pool;
+	const char *digestAlgo;
+	unsigned int  digestsize;
+	struct crypto_tfm *pools[1<<MAXIMUM_POOL_NUMBER];
+	/* optional, handy for statistics */
+	unsigned int pools_bytes[1<<MAXIMUM_POOL_NUMBER];
+
+	const char *cipherAlgo;
+	unsigned char key[RANDOM_MAX_DIGEST_SIZE];     /* the key */
+	unsigned int  keysize;
+	unsigned char iv[16];      /* the CTR value */
+	unsigned int  blocksize;
+	struct crypto_tfm *cipher;
+
+	unsigned int  pool_number; /* 2^pool_number # of pools */
+	unsigned int  pool_index;  /* current pool to add into */
+	unsigned int  pool0_len;   /* size of the first pool */
+	unsigned int  reseed_count; /* number of time we have reset */
+	struct crypto_tfm *reseedHash; /* digest used during random_reseed() */
+	struct crypto_tfm *networkCipher; /* cipher used for network randomness */
+	char networkCipher_ready;         /* flag indicating if networkCipher has been seeded */
 
-	/* read-write data: */
 	spinlock_t lock ____cacheline_aligned_in_smp;
-	unsigned	add_ptr;
-	int		entropy_count;
-	int		input_rotate;
 };
 
 /*
@@ -507,151 +442,107 @@
  *
  * Returns an negative error if there is a problem.
  */
-static int create_entropy_store(int size, struct entropy_store **ret_bucket)
+static int create_entropy_store(int pool_number_arg, struct entropy_store **ret_bucket)
 {
 	struct	entropy_store	*r;
-	struct	poolinfo	*p;
-	int	poolwords;
+	unsigned long pool_number;
+	int 	keysize, i, j;
 
-	poolwords = (size + 3) / 4; /* Convert bytes->words */
-	/* The pool size must be a multiple of 16 32-bit words */
-	poolwords = ((poolwords + 15) / 16) * 16;
-
-	for (p = poolinfo_table; p->poolwords; p++) {
-		if (poolwords == p->poolwords)
-			break;
-	}
-	if (p->poolwords == 0)
-		return -EINVAL;
+	pool_number = pool_number_arg;
+	if (pool_number < MINIMUM_POOL_NUMBER)
+		pool_number = MINIMUM_POOL_NUMBER;
 
 	r = kmalloc(sizeof(struct entropy_store), GFP_KERNEL);
-	if (!r)
+	if (!r) {
 		return -ENOMEM;
+	}
 
 	memset (r, 0, sizeof(struct entropy_store));
-	r->poolinfo = *p;
+	r->pool_number = pool_number;
+	r->digestAlgo = RANDOM_DEFAULT_DIGEST_ALGO;
 
-	r->pool = kmalloc(POOLBYTES, GFP_KERNEL);
-	if (!r->pool) {
-		kfree(r);
-		return -ENOMEM;
+DEBUG_PRINTK("create_entropy_store() pools=%u index=%u\n", 1<<pool_number, r->pool_index);
+	for (i=0; i<(1<<pool_number); i++) {
+DEBUG_PRINTK("create_entropy_store() i=%i index=%u\n", i, r->pool_index);
+		r->pools[i] = crypto_alloc_tfm(r->digestAlgo, 0);
+		if (r->pools[i] == NULL) {
+		  	for (j=0; j<i; j++) {
+				if (r->pools[j] != NULL) {
+					kfree(r->pools[j]);
+				}
+			}
+			kfree(r);
+			return -ENOMEM;
+		}
+		crypto_digest_init( r->pools[i] );
 	}
-	memset(r->pool, 0, POOLBYTES);
 	r->lock = SPIN_LOCK_UNLOCKED;
 	*ret_bucket = r;
-	return 0;
-}
 
-/* Clear the entropy pool and associated counters. */
-static void clear_entropy_store(struct entropy_store *r)
-{
-	r->add_ptr = 0;
-	r->entropy_count = 0;
-	r->input_rotate = 0;
-	memset(r->pool, 0, r->poolinfo.POOLBYTES);
-}
-#ifdef CONFIG_SYSCTL
-static void free_entropy_store(struct entropy_store *r)
-{
-	if (r->pool)
-		kfree(r->pool);
-	kfree(r);
-}
-#endif
-/*
- * This function adds a byte into the entropy "pool".  It does not
- * update the entropy estimate.  The caller should call
- * credit_entropy_store if this is appropriate.
- * 
- * The pool is stirred with a primitive polynomial of the appropriate
- * degree, and then twisted.  We twist by three bits at a time because
- * it's cheap to do so and helps slightly in the expected case where
- * the entropy is concentrated in the low-order bits.
- */
-static void add_entropy_words(struct entropy_store *r, const __u32 *in,
-			      int nwords)
-{
-	static __u32 const twist_table[8] = {
-		         0, 0x3b6e20c8, 0x76dc4190, 0x4db26158,
-		0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 };
-	unsigned long i, add_ptr, tap1, tap2, tap3, tap4, tap5;
-	int new_rotate, input_rotate;
-	int wordmask = r->poolinfo.poolwords - 1;
-	__u32 w, next_w;
-	unsigned long flags;
+	r->cipherAlgo = RANDOM_DEFAULT_CIPHER_ALGO;
+	if ((r->cipher=crypto_alloc_tfm(r->cipherAlgo, 0)) == NULL) {
+	  	return -ENOMEM;
+	}
 
-	/* Taps are constant, so we can load them without holding r->lock.  */
-	tap1 = r->poolinfo.tap1;
-	tap2 = r->poolinfo.tap2;
-	tap3 = r->poolinfo.tap3;
-	tap4 = r->poolinfo.tap4;
-	tap5 = r->poolinfo.tap5;
-	next_w = *in++;
+	/* If the HASH's output is greater then the cipher's keysize, truncate
+	 * to the cipher's keysize */
+	keysize = crypto_tfm_alg_max_keysize(r->cipher);
+	r->digestsize = crypto_tfm_alg_digestsize(r->pools[0]);
+	r->blocksize = crypto_tfm_alg_blocksize(r->cipher);
 
-	spin_lock_irqsave(&r->lock, flags);
-	prefetch_range(r->pool, wordmask);
-	input_rotate = r->input_rotate;
-	add_ptr = r->add_ptr;
-
-	while (nwords--) {
-		w = rotate_left(input_rotate, next_w);
-		if (nwords > 0)
-			next_w = *in++;
-		i = add_ptr = (add_ptr - 1) & wordmask;
-		/*
-		 * Normally, we add 7 bits of rotation to the pool.
-		 * At the beginning of the pool, add an extra 7 bits
-		 * rotation, so that successive passes spread the
-		 * input bits across the pool evenly.
-		 */
-		new_rotate = input_rotate + 14;
-		if (i)
-			new_rotate = input_rotate + 7;
-		input_rotate = new_rotate & 31;
-
-		/* XOR in the various taps */
-		w ^= r->pool[(i + tap1) & wordmask];
-		w ^= r->pool[(i + tap2) & wordmask];
-		w ^= r->pool[(i + tap3) & wordmask];
-		w ^= r->pool[(i + tap4) & wordmask];
-		w ^= r->pool[(i + tap5) & wordmask];
-		w ^= r->pool[i];
-		r->pool[i] = (w >> 3) ^ twist_table[w & 7];
+	r->keysize = (keysize < r->digestsize) ? keysize : r->digestsize;
+
+	if (crypto_cipher_setkey(r->cipher, r->key, r->keysize)) {
+		return -EINVAL;
 	}
 
-	r->input_rotate = input_rotate;
-	r->add_ptr = add_ptr;
+	/* digest used duing random-reseed() */
+	if ((r->reseedHash=crypto_alloc_tfm(r->digestAlgo, 0)) == NULL) {
+		return -ENOMEM;
+	}
+	/* cipher used for network randomness, init to key={zerovector}
+	 * for now */
+	if ((r->networkCipher=crypto_alloc_tfm(r->cipherAlgo, 0)) == NULL) {
+		return -ENOMEM;
+	}
 
-	spin_unlock_irqrestore(&r->lock, flags);
+	return 0;
 }
 
 /*
- * Credit (or debit) the entropy store with n bits of entropy
+ * This function adds a byte into the entropy "pool".
  */
-static void credit_entropy_store(struct entropy_store *r, int nbits)
+static void add_entropy_words(struct entropy_store *r, const __u32 *in,
+			      int nwords)
 {
 	unsigned long flags;
+	struct scatterlist sg[1];
+	static unsigned int totalBytes=0;
+
+	if (r == NULL) {
+		return;
+	}
 
 	spin_lock_irqsave(&r->lock, flags);
 
-	if (r->entropy_count + nbits < 0) {
-		DEBUG_ENT("negative entropy/overflow (%d+%d)\n",
-			  r->entropy_count, nbits);
-		r->entropy_count = 0;
-	} else if (r->entropy_count + nbits > r->poolinfo.POOLBITS) {
-		r->entropy_count = r->poolinfo.POOLBITS;
-	} else {
-		r->entropy_count += nbits;
-		if (nbits)
-			DEBUG_ENT("%04d %04d : added %d bits to %s\n",
-				  random_state->entropy_count,
-				  sec_random_state->entropy_count,
-				  nbits,
-				  r == sec_random_state ? "secondary" :
-				  r == random_state ? "primary" : "unknown");
+	totalBytes += nwords * sizeof(__u32);
+	r->pools_bytes[r->pool_index] += nwords * sizeof(__u32);
+
+	sg[0].page = virt_to_page(in);
+	sg[0].offset = offset_in_page(in);
+	sg[0].length = nwords*sizeof(__u32);
+	crypto_digest_update(r->pools[r->pool_index], sg, 1);
+
+	if (r->pool_index == 0) {
+		r->pool0_len += nwords*sizeof(__u32);
 	}
 
+	/* idx = (idx + 1) mod ( (2^N)-1 ) */
+	r->pool_index = (r->pool_index + 1) & ((1<<r->pool_number)-1);
+
 	spin_unlock_irqrestore(&r->lock, flags);
+DEBUG_PRINTK("0 add_entropy_words() nwords=%u pool[i].bytes=%u total=%u\n",
+	nwords, r->pools_bytes[r->pool_index], totalBytes);
 }
 
 /**********************************************************************
@@ -668,10 +559,10 @@
 };
 
 static struct sample *batch_entropy_pool, *batch_entropy_copy;
-static int	batch_head, batch_tail;
+static int      batch_head, batch_tail;
 static spinlock_t batch_lock = SPIN_LOCK_UNLOCKED;
 
-static int	batch_max;
+static int      batch_max;
 static void batch_entropy_process(void *private_);
 static DECLARE_WORK(batch_work, batch_entropy_process, NULL);
 
@@ -703,19 +594,20 @@
 	int new;
 	unsigned long flags;
 
-	if (!batch_max)
+	if (!batch_max) {
 		return;
+	}
 
 	spin_lock_irqsave(&batch_lock, flags);
 
 	batch_entropy_pool[batch_head].data[0] = a;
 	batch_entropy_pool[batch_head].data[1] = b;
-	batch_entropy_pool[batch_head].credit = num;
+	batch_entropy_pool[batch_head].credit = 0;
 
 	if (((batch_head - batch_tail) & (batch_max-1)) >= (batch_max / 2)) {
 		/*
-		 * Schedule it for the next timer tick:
-		 */
+		* Schedule it for the next timer tick:
+		*/
 		schedule_delayed_work(&batch_work, 1);
 	}
 
@@ -733,13 +625,11 @@
 
 /*
  * Flush out the accumulated entropy operations, adding entropy to the passed
- * store (normally random_state).  If that store has enough entropy, alternate
- * between randomizing the data of the primary and secondary stores.
+ * store (normally random_state).
  */
 static void batch_entropy_process(void *private_)
 {
-	struct entropy_store *r	= (struct entropy_store *) private_, *p;
-	int max_entropy = r->poolinfo.POOLBITS;
+	struct entropy_store *r = (struct entropy_store *) private_;
 	unsigned head, tail;
 
 	/* Mixing into the pool is expensive, so copy over the batch
@@ -750,7 +640,7 @@
 	spin_lock_irq(&batch_lock);
 
 	memcpy(batch_entropy_copy, batch_entropy_pool,
-	       batch_max*sizeof(struct sample));
+	batch_max*sizeof(struct sample));
 
 	head = batch_head;
 	tail = batch_tail;
@@ -758,61 +648,30 @@
 
 	spin_unlock_irq(&batch_lock);
 
-	p = r;
 	while (head != tail) {
-		if (r->entropy_count >= max_entropy) {
-			r = (r == sec_random_state) ?	random_state :
-							sec_random_state;
-			max_entropy = r->poolinfo.POOLBITS;
-		}
 		add_entropy_words(r, batch_entropy_copy[tail].data, 2);
-		credit_entropy_store(r, batch_entropy_copy[tail].credit);
 		tail = (tail+1) & (batch_max-1);
 	}
-	if (p->entropy_count >= random_read_wakeup_thresh)
-		wake_up_interruptible(&random_read_wait);
 }
 
+
 /*********************************************************************
  *
  * Entropy input management
  *
  *********************************************************************/
 
-/* There is one of these per entropy source */
-struct timer_rand_state {
-	__u32		last_time;
-	__s32		last_delta,last_delta2;
-	int		dont_count_entropy:1;
-};
-
-static struct timer_rand_state keyboard_timer_state;
-static struct timer_rand_state mouse_timer_state;
-static struct timer_rand_state extract_timer_state;
-static struct timer_rand_state *irq_timer_state[NR_IRQS];
-
 /*
  * This function adds entropy to the entropy "pool" by using timing
- * delays.  It uses the timer_rand_state structure to make an estimate
- * of how many bits of entropy this call has added to the pool.
+ * delays.
  *
  * The number "num" is also added to the pool - it should somehow describe
- * the type of event which just happened.  This is currently 0-255 for
- * keyboard scan codes, and 256 upwards for interrupts.
- * On the i386, this is assumed to be at most 16 bits, and the high bits
- * are used for a high-resolution timer.
- *
+ * the type of event which just happened.
  */
-static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
+static void add_timer_randomness(unsigned num)
 {
-	__u32		time;
-	__s32		delta, delta2, delta3;
-	int		entropy = 0;
-
-	/* if over the trickle threshold, use only 1 in 4096 samples */
-	if ( random_state->entropy_count > trickle_thresh &&
-	     (__get_cpu_var(trickle_count)++ & 0xfff))
-		return;
+	static __u32	lasttime=0;
+	__u32	time;
 
 #if defined (__i386__) || defined (__x86_64__)
 	if (cpu_has_tsc) {
@@ -822,480 +681,57 @@
 	} else {
 		time = jiffies;
 	}
-#elif defined (__sparc_v9__)
-	unsigned long tick = tick_ops->get_tick();
-
-	time = (unsigned int) tick;
-	num ^= (tick >> 32UL);
 #else
 	time = jiffies;
 #endif
 
-	/*
-	 * Calculate number of bits of randomness we probably added.
-	 * We take into account the first, second and third-order deltas
-	 * in order to make our estimate.
-	 */
-	if (!state->dont_count_entropy) {
-		delta = time - state->last_time;
-		state->last_time = time;
-
-		delta2 = delta - state->last_delta;
-		state->last_delta = delta;
-
-		delta3 = delta2 - state->last_delta2;
-		state->last_delta2 = delta2;
-
-		if (delta < 0)
-			delta = -delta;
-		if (delta2 < 0)
-			delta2 = -delta2;
-		if (delta3 < 0)
-			delta3 = -delta3;
-		if (delta > delta2)
-			delta = delta2;
-		if (delta > delta3)
-			delta = delta3;
-
-		/*
-		 * delta is now minimum absolute delta.
-		 * Round down by 1 bit on general principles,
-		 * and limit entropy entimate to 12 bits.
-		 */
-		delta >>= 1;
-		delta &= (1 << 12) - 1;
-
-		entropy = int_ln_12bits(delta);
+	/* Throttle our input to add_entropy_words() */
+	if ((time-lasttime) < RANDOM_INPUT_THROTTLE) {
+		return;
 	}
-	batch_entropy_store(num, time, entropy);
+	lasttime = time;
+
+	batch_entropy_store(num, time, 0);
 }
 
 void add_keyboard_randomness(unsigned char scancode)
 {
-	static unsigned char last_scancode;
-	/* ignore autorepeat (multiple key down w/o key up) */
-	if (scancode != last_scancode) {
-		last_scancode = scancode;
-		add_timer_randomness(&keyboard_timer_state, scancode);
-	}
+	/* jlcooke: we don't care about auto-repeats,
+	 * they can't hurt us anymore */
+	add_timer_randomness(scancode);
 }
 
 EXPORT_SYMBOL(add_keyboard_randomness);
 
 void add_mouse_randomness(__u32 mouse_data)
 {
-	add_timer_randomness(&mouse_timer_state, mouse_data);
+	add_timer_randomness(mouse_data);
 }
 
 EXPORT_SYMBOL(add_mouse_randomness);
 
 void add_interrupt_randomness(int irq)
 {
-	if (irq >= NR_IRQS || irq_timer_state[irq] == 0)
+	if (irq >= NR_IRQS)
 		return;
 
-	add_timer_randomness(irq_timer_state[irq], 0x100+irq);
+	/* jlcooke: no need to add 0x100 ... not random! :P */
+	add_timer_randomness(irq);
 }
 
 EXPORT_SYMBOL(add_interrupt_randomness);
 
 void add_disk_randomness(struct gendisk *disk)
 {
-	if (!disk || !disk->random)
+	if (!disk)
 		return;
-	/* first major is 1, so we get >= 0x200 here */
-	add_timer_randomness(disk->random, 0x100+MKDEV(disk->major, disk->first_minor));
+
+	/* jlcooke: no need to add 0x100 ... not random! :P */
+	add_timer_randomness(MKDEV(disk->major, disk->first_minor));
 }
 
 EXPORT_SYMBOL(add_disk_randomness);
 
-/******************************************************************
- *
- * Hash function definition
- *
- *******************************************************************/
-
-/*
- * This chunk of code defines a function
- * void HASH_TRANSFORM(__u32 digest[HASH_BUFFER_SIZE + HASH_EXTRA_SIZE],
- * 		__u32 const data[16])
- * 
- * The function hashes the input data to produce a digest in the first
- * HASH_BUFFER_SIZE words of the digest[] array, and uses HASH_EXTRA_SIZE
- * more words for internal purposes.  (This buffer is exported so the
- * caller can wipe it once rather than this code doing it each call,
- * and tacking it onto the end of the digest[] array is the quick and
- * dirty way of doing it.)
- *
- * It so happens that MD5 and SHA share most of the initial vector
- * used to initialize the digest[] array before the first call:
- * 1) 0x67452301
- * 2) 0xefcdab89
- * 3) 0x98badcfe
- * 4) 0x10325476
- * 5) 0xc3d2e1f0 (SHA only)
- * 
- * For /dev/random purposes, the length of the data being hashed is
- * fixed in length, so appending a bit count in the usual way is not
- * cryptographically necessary.
- */
-
-#ifdef USE_SHA
-
-#define HASH_BUFFER_SIZE 5
-#define HASH_EXTRA_SIZE 80
-#define HASH_TRANSFORM SHATransform
-
-/* Various size/speed tradeoffs are available.  Choose 0..3. */
-#define SHA_CODE_SIZE 0
-
-/*
- * SHA transform algorithm, taken from code written by Peter Gutmann,
- * and placed in the public domain.
- */
-
-/* The SHA f()-functions.  */
-
-#define f1(x,y,z)   ( z ^ (x & (y^z)) )		/* Rounds  0-19: x ? y : z */
-#define f2(x,y,z)   (x ^ y ^ z)			/* Rounds 20-39: XOR */
-#define f3(x,y,z)   ( (x & y) + (z & (x ^ y)) )	/* Rounds 40-59: majority */
-#define f4(x,y,z)   (x ^ y ^ z)			/* Rounds 60-79: XOR */
-
-/* The SHA Mysterious Constants */
-
-#define K1  0x5A827999L			/* Rounds  0-19: sqrt(2) * 2^30 */
-#define K2  0x6ED9EBA1L			/* Rounds 20-39: sqrt(3) * 2^30 */
-#define K3  0x8F1BBCDCL			/* Rounds 40-59: sqrt(5) * 2^30 */
-#define K4  0xCA62C1D6L			/* Rounds 60-79: sqrt(10) * 2^30 */
-
-#define ROTL(n,X)  ( ( ( X ) << n ) | ( ( X ) >> ( 32 - n ) ) )
-
-#define subRound(a, b, c, d, e, f, k, data) \
-    ( e += ROTL( 5, a ) + f( b, c, d ) + k + data, b = ROTL( 30, b ) )
-
-
-static void SHATransform(__u32 digest[85], __u32 const data[16])
-{
-    __u32 A, B, C, D, E;     /* Local vars */
-    __u32 TEMP;
-    int	i;
-#define W (digest + HASH_BUFFER_SIZE)	/* Expanded data array */
-
-    /*
-     * Do the preliminary expansion of 16 to 80 words.  Doing it
-     * out-of-line line this is faster than doing it in-line on
-     * register-starved machines like the x86, and not really any
-     * slower on real processors.
-     */
-    memcpy(W, data, 16*sizeof(__u32));
-    for (i = 0; i < 64; i++) {
-	    TEMP = W[i] ^ W[i+2] ^ W[i+8] ^ W[i+13];
-	    W[i+16] = ROTL(1, TEMP);
-    }
-
-    /* Set up first buffer and local data buffer */
-    A = digest[ 0 ];
-    B = digest[ 1 ];
-    C = digest[ 2 ];
-    D = digest[ 3 ];
-    E = digest[ 4 ];
-
-    /* Heavy mangling, in 4 sub-rounds of 20 iterations each. */
-#if SHA_CODE_SIZE == 0
-    /*
-     * Approximately 50% of the speed of the largest version, but
-     * takes up 1/16 the space.  Saves about 6k on an i386 kernel.
-     */
-    for (i = 0; i < 80; i++) {
-	if (i < 40) {
-	    if (i < 20)
-		TEMP = f1(B, C, D) + K1;
-	    else
-		TEMP = f2(B, C, D) + K2;
-	} else {
-	    if (i < 60)
-		TEMP = f3(B, C, D) + K3;
-	    else
-		TEMP = f4(B, C, D) + K4;
-	}
-	TEMP += ROTL(5, A) + E + W[i];
-	E = D; D = C; C = ROTL(30, B); B = A; A = TEMP;
-    }
-#elif SHA_CODE_SIZE == 1
-    for (i = 0; i < 20; i++) {
-	TEMP = f1(B, C, D) + K1 + ROTL(5, A) + E + W[i];
-	E = D; D = C; C = ROTL(30, B); B = A; A = TEMP;
-    }
-    for (; i < 40; i++) {
-	TEMP = f2(B, C, D) + K2 + ROTL(5, A) + E + W[i];
-	E = D; D = C; C = ROTL(30, B); B = A; A = TEMP;
-    }
-    for (; i < 60; i++) {
-	TEMP = f3(B, C, D) + K3 + ROTL(5, A) + E + W[i];
-	E = D; D = C; C = ROTL(30, B); B = A; A = TEMP;
-    }
-    for (; i < 80; i++) {
-	TEMP = f4(B, C, D) + K4 + ROTL(5, A) + E + W[i];
-	E = D; D = C; C = ROTL(30, B); B = A; A = TEMP;
-    }
-#elif SHA_CODE_SIZE == 2
-    for (i = 0; i < 20; i += 5) {
-	subRound( A, B, C, D, E, f1, K1, W[ i   ] );
-	subRound( E, A, B, C, D, f1, K1, W[ i+1 ] );
-	subRound( D, E, A, B, C, f1, K1, W[ i+2 ] );
-	subRound( C, D, E, A, B, f1, K1, W[ i+3 ] );
-	subRound( B, C, D, E, A, f1, K1, W[ i+4 ] );
-    }
-    for (; i < 40; i += 5) {
-	subRound( A, B, C, D, E, f2, K2, W[ i   ] );
-	subRound( E, A, B, C, D, f2, K2, W[ i+1 ] );
-	subRound( D, E, A, B, C, f2, K2, W[ i+2 ] );
-	subRound( C, D, E, A, B, f2, K2, W[ i+3 ] );
-	subRound( B, C, D, E, A, f2, K2, W[ i+4 ] );
-    }
-    for (; i < 60; i += 5) {
-	subRound( A, B, C, D, E, f3, K3, W[ i   ] );
-	subRound( E, A, B, C, D, f3, K3, W[ i+1 ] );
-	subRound( D, E, A, B, C, f3, K3, W[ i+2 ] );
-	subRound( C, D, E, A, B, f3, K3, W[ i+3 ] );
-	subRound( B, C, D, E, A, f3, K3, W[ i+4 ] );
-    }
-    for (; i < 80; i += 5) {
-	subRound( A, B, C, D, E, f4, K4, W[ i   ] );
-	subRound( E, A, B, C, D, f4, K4, W[ i+1 ] );
-	subRound( D, E, A, B, C, f4, K4, W[ i+2 ] );
-	subRound( C, D, E, A, B, f4, K4, W[ i+3 ] );
-	subRound( B, C, D, E, A, f4, K4, W[ i+4 ] );
-    }
-#elif SHA_CODE_SIZE == 3 /* Really large version */
-    subRound( A, B, C, D, E, f1, K1, W[  0 ] );
-    subRound( E, A, B, C, D, f1, K1, W[  1 ] );
-    subRound( D, E, A, B, C, f1, K1, W[  2 ] );
-    subRound( C, D, E, A, B, f1, K1, W[  3 ] );
-    subRound( B, C, D, E, A, f1, K1, W[  4 ] );
-    subRound( A, B, C, D, E, f1, K1, W[  5 ] );
-    subRound( E, A, B, C, D, f1, K1, W[  6 ] );
-    subRound( D, E, A, B, C, f1, K1, W[  7 ] );
-    subRound( C, D, E, A, B, f1, K1, W[  8 ] );
-    subRound( B, C, D, E, A, f1, K1, W[  9 ] );
-    subRound( A, B, C, D, E, f1, K1, W[ 10 ] );
-    subRound( E, A, B, C, D, f1, K1, W[ 11 ] );
-    subRound( D, E, A, B, C, f1, K1, W[ 12 ] );
-    subRound( C, D, E, A, B, f1, K1, W[ 13 ] );
-    subRound( B, C, D, E, A, f1, K1, W[ 14 ] );
-    subRound( A, B, C, D, E, f1, K1, W[ 15 ] );
-    subRound( E, A, B, C, D, f1, K1, W[ 16 ] );
-    subRound( D, E, A, B, C, f1, K1, W[ 17 ] );
-    subRound( C, D, E, A, B, f1, K1, W[ 18 ] );
-    subRound( B, C, D, E, A, f1, K1, W[ 19 ] );
-
-    subRound( A, B, C, D, E, f2, K2, W[ 20 ] );
-    subRound( E, A, B, C, D, f2, K2, W[ 21 ] );
-    subRound( D, E, A, B, C, f2, K2, W[ 22 ] );
-    subRound( C, D, E, A, B, f2, K2, W[ 23 ] );
-    subRound( B, C, D, E, A, f2, K2, W[ 24 ] );
-    subRound( A, B, C, D, E, f2, K2, W[ 25 ] );
-    subRound( E, A, B, C, D, f2, K2, W[ 26 ] );
-    subRound( D, E, A, B, C, f2, K2, W[ 27 ] );
-    subRound( C, D, E, A, B, f2, K2, W[ 28 ] );
-    subRound( B, C, D, E, A, f2, K2, W[ 29 ] );
-    subRound( A, B, C, D, E, f2, K2, W[ 30 ] );
-    subRound( E, A, B, C, D, f2, K2, W[ 31 ] );
-    subRound( D, E, A, B, C, f2, K2, W[ 32 ] );
-    subRound( C, D, E, A, B, f2, K2, W[ 33 ] );
-    subRound( B, C, D, E, A, f2, K2, W[ 34 ] );
-    subRound( A, B, C, D, E, f2, K2, W[ 35 ] );
-    subRound( E, A, B, C, D, f2, K2, W[ 36 ] );
-    subRound( D, E, A, B, C, f2, K2, W[ 37 ] );
-    subRound( C, D, E, A, B, f2, K2, W[ 38 ] );
-    subRound( B, C, D, E, A, f2, K2, W[ 39 ] );
-    
-    subRound( A, B, C, D, E, f3, K3, W[ 40 ] );
-    subRound( E, A, B, C, D, f3, K3, W[ 41 ] );
-    subRound( D, E, A, B, C, f3, K3, W[ 42 ] );
-    subRound( C, D, E, A, B, f3, K3, W[ 43 ] );
-    subRound( B, C, D, E, A, f3, K3, W[ 44 ] );
-    subRound( A, B, C, D, E, f3, K3, W[ 45 ] );
-    subRound( E, A, B, C, D, f3, K3, W[ 46 ] );
-    subRound( D, E, A, B, C, f3, K3, W[ 47 ] );
-    subRound( C, D, E, A, B, f3, K3, W[ 48 ] );
-    subRound( B, C, D, E, A, f3, K3, W[ 49 ] );
-    subRound( A, B, C, D, E, f3, K3, W[ 50 ] );
-    subRound( E, A, B, C, D, f3, K3, W[ 51 ] );
-    subRound( D, E, A, B, C, f3, K3, W[ 52 ] );
-    subRound( C, D, E, A, B, f3, K3, W[ 53 ] );
-    subRound( B, C, D, E, A, f3, K3, W[ 54 ] );
-    subRound( A, B, C, D, E, f3, K3, W[ 55 ] );
-    subRound( E, A, B, C, D, f3, K3, W[ 56 ] );
-    subRound( D, E, A, B, C, f3, K3, W[ 57 ] );
-    subRound( C, D, E, A, B, f3, K3, W[ 58 ] );
-    subRound( B, C, D, E, A, f3, K3, W[ 59 ] );
-
-    subRound( A, B, C, D, E, f4, K4, W[ 60 ] );
-    subRound( E, A, B, C, D, f4, K4, W[ 61 ] );
-    subRound( D, E, A, B, C, f4, K4, W[ 62 ] );
-    subRound( C, D, E, A, B, f4, K4, W[ 63 ] );
-    subRound( B, C, D, E, A, f4, K4, W[ 64 ] );
-    subRound( A, B, C, D, E, f4, K4, W[ 65 ] );
-    subRound( E, A, B, C, D, f4, K4, W[ 66 ] );
-    subRound( D, E, A, B, C, f4, K4, W[ 67 ] );
-    subRound( C, D, E, A, B, f4, K4, W[ 68 ] );
-    subRound( B, C, D, E, A, f4, K4, W[ 69 ] );
-    subRound( A, B, C, D, E, f4, K4, W[ 70 ] );
-    subRound( E, A, B, C, D, f4, K4, W[ 71 ] );
-    subRound( D, E, A, B, C, f4, K4, W[ 72 ] );
-    subRound( C, D, E, A, B, f4, K4, W[ 73 ] );
-    subRound( B, C, D, E, A, f4, K4, W[ 74 ] );
-    subRound( A, B, C, D, E, f4, K4, W[ 75 ] );
-    subRound( E, A, B, C, D, f4, K4, W[ 76 ] );
-    subRound( D, E, A, B, C, f4, K4, W[ 77 ] );
-    subRound( C, D, E, A, B, f4, K4, W[ 78 ] );
-    subRound( B, C, D, E, A, f4, K4, W[ 79 ] );
-#else
-#error Illegal SHA_CODE_SIZE
-#endif
-
-    /* Build message digest */
-    digest[ 0 ] += A;
-    digest[ 1 ] += B;
-    digest[ 2 ] += C;
-    digest[ 3 ] += D;
-    digest[ 4 ] += E;
-
-	/* W is wiped by the caller */
-#undef W
-}
-
-#undef ROTL
-#undef f1
-#undef f2
-#undef f3
-#undef f4
-#undef K1	
-#undef K2
-#undef K3	
-#undef K4	
-#undef subRound
-	
-#else /* !USE_SHA - Use MD5 */
-
-#define HASH_BUFFER_SIZE 4
-#define HASH_EXTRA_SIZE 0
-#define HASH_TRANSFORM MD5Transform
-	
-/*
- * MD5 transform algorithm, taken from code written by Colin Plumb,
- * and put into the public domain
- */
-
-/* The four core functions - F1 is optimized somewhat */
-
-/* #define F1(x, y, z) (x & y | ~x & z) */
-#define F1(x, y, z) (z ^ (x & (y ^ z)))
-#define F2(x, y, z) F1(z, x, y)
-#define F3(x, y, z) (x ^ y ^ z)
-#define F4(x, y, z) (y ^ (x | ~z))
-
-/* This is the central step in the MD5 algorithm. */
-#define MD5STEP(f, w, x, y, z, data, s) \
-	( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
-
-/*
- * The core of the MD5 algorithm, this alters an existing MD5 hash to
- * reflect the addition of 16 longwords of new data.  MD5Update blocks
- * the data and converts bytes into longwords for this routine.
- */
-static void MD5Transform(__u32 buf[HASH_BUFFER_SIZE], __u32 const in[16])
-{
-	__u32 a, b, c, d;
-
-	a = buf[0];
-	b = buf[1];
-	c = buf[2];
-	d = buf[3];
-
-	MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478,  7);
-	MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12);
-	MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17);
-	MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22);
-	MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf,  7);
-	MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12);
-	MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17);
-	MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22);
-	MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8,  7);
-	MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12);
-	MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17);
-	MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22);
-	MD5STEP(F1, a, b, c, d, in[12]+0x6b901122,  7);
-	MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12);
-	MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17);
-	MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22);
-
-	MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562,  5);
-	MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340,  9);
-	MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14);
-	MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20);
-	MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d,  5);
-	MD5STEP(F2, d, a, b, c, in[10]+0x02441453,  9);
-	MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14);
-	MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20);
-	MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6,  5);
-	MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6,  9);
-	MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14);
-	MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20);
-	MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905,  5);
-	MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8,  9);
-	MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14);
-	MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20);
-
-	MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942,  4);
-	MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11);
-	MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16);
-	MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23);
-	MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44,  4);
-	MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11);
-	MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16);
-	MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23);
-	MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6,  4);
-	MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11);
-	MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16);
-	MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23);
-	MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039,  4);
-	MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11);
-	MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16);
-	MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23);
-
-	MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244,  6);
-	MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10);
-	MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15);
-	MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21);
-	MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3,  6);
-	MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10);
-	MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15);
-	MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21);
-	MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f,  6);
-	MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10);
-	MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15);
-	MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21);
-	MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82,  6);
-	MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10);
-	MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15);
-	MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21);
-
-	buf[0] += a;
-	buf[1] += b;
-	buf[2] += c;
-	buf[3] += d;
-}
-
-#undef F1
-#undef F2
-#undef F3
-#undef F4
-#undef MD5STEP
-
-#endif /* !USE_SHA */
-
 /*********************************************************************
  *
  * Entropy extraction routines
@@ -1305,169 +741,145 @@
 #define EXTRACT_ENTROPY_USER		1
 #define EXTRACT_ENTROPY_SECONDARY	2
 #define EXTRACT_ENTROPY_LIMIT		4
-#define TMP_BUF_SIZE			(HASH_BUFFER_SIZE + HASH_EXTRA_SIZE)
-#define SEC_XFER_SIZE			(TMP_BUF_SIZE*4)
+#define CRYPTO_MAX_BLOCK_SIZE		32
 
 static ssize_t extract_entropy(struct entropy_store *r, void * buf,
 			       size_t nbytes, int flags);
 
+static inline void increment_iv(unsigned char *IV, const unsigned int IVsize) {
+	unsigned int i;
+	for (i=0; i<IVsize; i++) {
+		if ( ++(IV[i]) ) {
+			break;
+		}
+	}
+}
+
 /*
- * This utility inline function is responsible for transfering entropy
- * from the primary pool to the secondary extraction pool. We make
- * sure we pull enough for a 'catastrophic reseed'.
- */
-static inline void xfer_secondary_pool(struct entropy_store *r,
-				       size_t nbytes, __u32 *tmp)
-{
-	if (r->entropy_count < nbytes * 8 &&
-	    r->entropy_count < r->poolinfo.POOLBITS) {
-		int bytes = max_t(int, random_read_wakeup_thresh / 8,
-				min_t(int, nbytes, TMP_BUF_SIZE));
-
-		DEBUG_ENT("%04d %04d : going to reseed %s with %d bits "
-			  "(%d of %d requested)\n",
-			  random_state->entropy_count,
-			  sec_random_state->entropy_count,
-			  r == sec_random_state ? "secondary" : "unknown",
-			  bytes * 8, nbytes * 8, r->entropy_count);
-
-		bytes=extract_entropy(random_state, tmp, bytes,
-				      EXTRACT_ENTROPY_LIMIT);
-		add_entropy_words(r, tmp, bytes);
-		credit_entropy_store(r, bytes*8);
+ * Fortuna's Reseed is ...
+ */
+static void random_reseed(struct entropy_store *r) {
+	struct scatterlist sg[1];
+	int i;
+	unsigned char tmp[RANDOM_MAX_DIGEST_SIZE];
+
+	r->reseed_count++;
+
+	crypto_digest_init(r->reseedHash);
+
+	sg[0].page = virt_to_page(r->key);
+	sg[0].offset = offset_in_page(r->key);
+	sg[0].length = r->keysize;
+	crypto_digest_update(r->reseedHash, sg, 1);
+
+#define TESTBIT(VAL, N)\
+  ( ((VAL) >> (N)) & 1 )
+	for (i=0; i<(1<<r->pool_number); i++) {
+		/* using pool[i] if r->reseed_count is divisible by 2^i
+		 * since 2^0 == 1, we always use pool[0]
+		 */
+		if ( (i==0)  ||  TESTBIT(r->reseed_count,i)==0 ) {
+			crypto_digest_final(r->pools[i], tmp);
+
+			sg[0].page = virt_to_page(tmp);
+			sg[0].offset = offset_in_page(tmp);
+			sg[0].length = r->keysize;
+			crypto_digest_update(r->reseedHash, sg, 1);
+
+			crypto_digest_init(r->pools[i]);
+			/* should each pool carry it's past state forward? */
+			crypto_digest_update(r->pools[i], sg, 1);
+		} else {
+			/* pool N can only be used once every 2^N times */
+			break;
+		}
 	}
+#undef TESTBIT
+
+	crypto_digest_final(r->reseedHash, r->key);
+	crypto_cipher_setkey(r->cipher, r->key, r->keysize);
+	increment_iv(r->iv, r->blocksize);
 }
 
 /*
  * This function extracts randomness from the "entropy pool", and
- * returns it in a buffer.  This function computes how many remaining
- * bits of entropy are left in the pool, but it does not restrict the
- * number of bytes that are actually obtained.  If the EXTRACT_ENTROPY_USER
+ * returns it in a buffer.  If the EXTRACT_ENTROPY_USER
  * flag is given, then the buf pointer is assumed to be in user space.
- *
- * If the EXTRACT_ENTROPY_SECONDARY flag is given, then we are actually
- * extracting entropy from the secondary pool, and can refill from the
- * primary pool if needed.
- *
- * Note: extract_entropy() assumes that .poolwords is a multiple of 16 words.
  */
 static ssize_t extract_entropy(struct entropy_store *r, void * buf,
 			       size_t nbytes, int flags)
 {
 	ssize_t ret, i;
-	__u32 tmp[TMP_BUF_SIZE];
-	__u32 x;
+	__u32 tmp[CRYPTO_MAX_BLOCK_SIZE];
 	unsigned long cpuflags;
+	struct scatterlist sgiv[1],
+			   sgtmp[1];
 
-
-	/* Redundant, but just in case... */
-	if (r->entropy_count > r->poolinfo.POOLBITS)
-		r->entropy_count = r->poolinfo.POOLBITS;
-
-	if (flags & EXTRACT_ENTROPY_SECONDARY)
-		xfer_secondary_pool(r, nbytes, tmp);
-
-	/* Hold lock while accounting */
+	/* lock while we're reseeding */
 	spin_lock_irqsave(&r->lock, cpuflags);
 
-	DEBUG_ENT("%04d %04d : trying to extract %d bits from %s\n",
-		  random_state->entropy_count,
-		  sec_random_state->entropy_count,
-		  nbytes * 8,
-		  r == sec_random_state ? "secondary" :
-		  r == random_state ? "primary" : "unknown");
-
-	if (flags & EXTRACT_ENTROPY_LIMIT && nbytes >= r->entropy_count / 8)
-		nbytes = r->entropy_count / 8;
-
-	if (r->entropy_count / 8 >= nbytes)
-		r->entropy_count -= nbytes*8;
-	else
-		r->entropy_count = 0;
+	random_reseed(r);
+	r->pool0_len = 0;
 
-	if (r->entropy_count < random_write_wakeup_thresh)
-		wake_up_interruptible(&random_write_wait);
+	spin_unlock_irqrestore(&r->lock, cpuflags);
 
-	DEBUG_ENT("%04d %04d : debiting %d bits from %s%s\n",
-		  random_state->entropy_count,
-		  sec_random_state->entropy_count,
-		  nbytes * 8,
-		  r == sec_random_state ? "secondary" :
-		  r == random_state ? "primary" : "unknown",
-		  flags & EXTRACT_ENTROPY_LIMIT ? "" : " (unlimited)");
+	/*
+	 * don't output any data until we reseed at least once
+	 * But this causes problems at boot-time.  So weĺl assume since they
+	 * don't wait to the PRNG to setup, they don't really new strong random
+	 * data
+	*/
+	/*
+	if (r->reseed_count == 0)
+		return 0;
+	*/
 
-	spin_unlock_irqrestore(&r->lock, cpuflags);
+	sgiv[0].page = virt_to_page(r->iv);
+	sgiv[0].offset = offset_in_page(r->iv);
+	sgiv[0].length = r->blocksize;
+	sgtmp[0].page = virt_to_page(tmp);
+	sgtmp[0].offset = offset_in_page(tmp);
+	sgtmp[0].length = r->blocksize;
 
 	ret = 0;
 	while (nbytes) {
-		/*
-		 * Check if we need to break out or reschedule....
-		 */
-		if ((flags & EXTRACT_ENTROPY_USER) && need_resched()) {
-			if (signal_pending(current)) {
-				if (ret == 0)
-					ret = -ERESTARTSYS;
-				break;
-			}
+		crypto_cipher_encrypt(r->cipher, sgtmp, sgiv, r->blocksize);
+		increment_iv(r->iv, r->blocksize);
 
-			DEBUG_ENT("%04d %04d : extract feeling sleepy (%d bytes left)\n",
-				  random_state->entropy_count,
-				  sec_random_state->entropy_count, nbytes);
-
-			schedule();
-
-			DEBUG_ENT("%04d %04d : extract woke up\n",
-				  random_state->entropy_count,
-				  sec_random_state->entropy_count);
-		}
-
-		/* Hash the pool to get the output */
-		tmp[0] = 0x67452301;
-		tmp[1] = 0xefcdab89;
-		tmp[2] = 0x98badcfe;
-		tmp[3] = 0x10325476;
-#ifdef USE_SHA
-		tmp[4] = 0xc3d2e1f0;
-#endif
-		/*
-		 * As we hash the pool, we mix intermediate values of
-		 * the hash back into the pool.  This eliminates
-		 * backtracking attacks (where the attacker knows
-		 * the state of the pool plus the current outputs, and
-		 * attempts to find previous ouputs), unless the hash
-		 * function can be inverted.
-		 */
-		for (i = 0, x = 0; i < r->poolinfo.poolwords; i += 16, x+=2) {
-			HASH_TRANSFORM(tmp, r->pool+i);
-			add_entropy_words(r, &tmp[x%HASH_BUFFER_SIZE], 1);
-		}
-		
-		/*
-		 * In case the hash function has some recognizable
-		 * output pattern, we fold it in half.
-		 */
-		for (i = 0; i <  HASH_BUFFER_SIZE/2; i++)
-			tmp[i] ^= tmp[i + (HASH_BUFFER_SIZE+1)/2];
-#if HASH_BUFFER_SIZE & 1	/* There's a middle word to deal with */
-		x = tmp[HASH_BUFFER_SIZE/2];
-		x ^= (x >> 16);		/* Fold it in half */
-		((__u16 *)tmp)[HASH_BUFFER_SIZE-1] = (__u16)x;
-#endif
-		
 		/* Copy data to destination buffer */
-		i = min(nbytes, HASH_BUFFER_SIZE*sizeof(__u32)/2);
+		i = (nbytes < 16) ? nbytes : 16;
 		if (flags & EXTRACT_ENTROPY_USER) {
 			i -= copy_to_user(buf, (__u8 const *)tmp, i);
 			if (!i) {
 				ret = -EFAULT;
 				break;
 			}
-		} else
+		} else {
 			memcpy(buf, (__u8 const *)tmp, i);
+		}
 		nbytes -= i;
 		buf += i;
 		ret += i;
 	}
+	
+	/* generate a new key */
+	/* take into account the possibility that keysize >= blocksize */
+	for (i=0; i+r->blocksize<=r->keysize; i+=r->blocksize) {
+		sgtmp[0].page = virt_to_page( r->key+i );
+		sgtmp[0].offset = offset_in_page( r->key+i );
+		sgtmp[0].length = r->blocksize;
+		crypto_cipher_encrypt(r->cipher, sgtmp, sgiv, 1);
+		increment_iv(r->iv, r->blocksize);
+	}
+	sgtmp[0].page = virt_to_page( r->key+i );
+	sgtmp[0].offset = offset_in_page( r->key+i );
+	sgtmp[0].length = r->blocksize-i;
+	crypto_cipher_encrypt(r->cipher, sgtmp, sgiv, 1);
+	increment_iv(r->iv, r->blocksize);
+
+	if (crypto_cipher_setkey(r->cipher, r->key, r->keysize)) {
+		return -EINVAL;
+	}
 
 	/* Wipe data just returned from memory */
 	memset(tmp, 0, sizeof(tmp));
@@ -1482,10 +894,7 @@
  */
 void get_random_bytes(void *buf, int nbytes)
 {
-	if (sec_random_state)  
-		extract_entropy(sec_random_state, (char *) buf, nbytes, 
-				EXTRACT_ENTROPY_SECONDARY);
-	else if (random_state)
+	if (random_state)
 		extract_entropy(random_state, (char *) buf, nbytes, 0);
 	else
 		printk(KERN_NOTICE "get_random_bytes called before "
@@ -1500,57 +909,16 @@
  *
  *********************************************************************/
 
-/*
- * Initialize the random pool with standard stuff.
- *
- * NOTE: This is an OS-dependent function.
- */
-static void init_std_data(struct entropy_store *r)
-{
-	struct timeval 	tv;
-	__u32		words[2];
-	char 		*p;
-	int		i;
-
-	do_gettimeofday(&tv);
-	words[0] = tv.tv_sec;
-	words[1] = tv.tv_usec;
-	add_entropy_words(r, words, 2);
-
-	/*
-	 *	This doesn't lock system.utsname. However, we are generating
-	 *	entropy so a race with a name set here is fine.
-	 */
-	p = (char *) &system_utsname;
-	for (i = sizeof(system_utsname) / sizeof(words); i; i--) {
-		memcpy(words, p, sizeof(words));
-		add_entropy_words(r, words, sizeof(words)/4);
-		p += sizeof(words);
-	}
-}
-
 static int __init rand_initialize(void)
 {
-	int i;
-
-	if (create_entropy_store(DEFAULT_POOL_SIZE, &random_state))
-		goto err;
-	if (batch_entropy_init(BATCH_ENTROPY_SIZE, random_state))
-		goto err;
-	if (create_entropy_store(SECONDARY_POOL_SIZE, &sec_random_state))
+	if (create_entropy_store(DEFAULT_POOL_NUMBER, &random_state))
 		goto err;
-	clear_entropy_store(random_state);
-	clear_entropy_store(sec_random_state);
-	init_std_data(random_state);
+        if (batch_entropy_init(BATCH_ENTROPY_SIZE, random_state))
+                goto err;
+
 #ifdef CONFIG_SYSCTL
 	sysctl_init_random(random_state);
 #endif
-	for (i = 0; i < NR_IRQS; i++)
-		irq_timer_state[i] = NULL;
-	memset(&keyboard_timer_state, 0, sizeof(struct timer_rand_state));
-	memset(&mouse_timer_state, 0, sizeof(struct timer_rand_state));
-	memset(&extract_timer_state, 0, sizeof(struct timer_rand_state));
-	extract_timer_state.dont_count_entropy = 1;
 	return 0;
 err:
 	return -1;
@@ -1559,139 +927,33 @@
 
 void rand_initialize_irq(int irq)
 {
-	struct timer_rand_state *state;
-	
-	if (irq >= NR_IRQS || irq_timer_state[irq])
-		return;
-
-	/*
-	 * If kmalloc returns null, we just won't use that entropy
-	 * source.
-	 */
-	state = kmalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
-	if (state) {
-		memset(state, 0, sizeof(struct timer_rand_state));
-		irq_timer_state[irq] = state;
-	}
+	/* we don't use timers anymore, we just use the current time */
 }
  
 void rand_initialize_disk(struct gendisk *disk)
 {
-	struct timer_rand_state *state;
-	
-	/*
-	 * If kmalloc returns null, we just won't use that entropy
-	 * source.
-	 */
-	state = kmalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
-	if (state) {
-		memset(state, 0, sizeof(struct timer_rand_state));
-		disk->random = state;
-	}
-}
-
-static ssize_t
-random_read(struct file * file, char __user * buf, size_t nbytes, loff_t *ppos)
-{
-	DECLARE_WAITQUEUE(wait, current);
-	ssize_t			n, retval = 0, count = 0;
-	
-	if (nbytes == 0)
-		return 0;
-
-	while (nbytes > 0) {
-		n = nbytes;
-		if (n > SEC_XFER_SIZE)
-			n = SEC_XFER_SIZE;
-
-		DEBUG_ENT("%04d %04d : reading %d bits, p: %d s: %d\n",
-			  random_state->entropy_count,
-			  sec_random_state->entropy_count,
-			  n*8, random_state->entropy_count,
-			  sec_random_state->entropy_count);
-
-		n = extract_entropy(sec_random_state, buf, n,
-				    EXTRACT_ENTROPY_USER |
-				    EXTRACT_ENTROPY_LIMIT |
-				    EXTRACT_ENTROPY_SECONDARY);
-
-		DEBUG_ENT("%04d %04d : read got %d bits (%d still needed)\n",
-			  random_state->entropy_count,
-			  sec_random_state->entropy_count,
-			  n*8, (nbytes-n)*8);
-
-		if (n == 0) {
-			if (file->f_flags & O_NONBLOCK) {
-				retval = -EAGAIN;
-				break;
-			}
-			if (signal_pending(current)) {
-				retval = -ERESTARTSYS;
-				break;
-			}
-
-			DEBUG_ENT("%04d %04d : sleeping?\n",
-				  random_state->entropy_count,
-				  sec_random_state->entropy_count);
-
-			set_current_state(TASK_INTERRUPTIBLE);
-			add_wait_queue(&random_read_wait, &wait);
-
-			if (sec_random_state->entropy_count / 8 == 0)
-				schedule();
-
-			set_current_state(TASK_RUNNING);
-			remove_wait_queue(&random_read_wait, &wait);
-
-			DEBUG_ENT("%04d %04d : waking up\n",
-				  random_state->entropy_count,
-				  sec_random_state->entropy_count);
-
-			continue;
-		}
-
-		if (n < 0) {
-			retval = n;
-			break;
-		}
-		count += n;
-		buf += n;
-		nbytes -= n;
-		break;		/* This break makes the device work */
-				/* like a named pipe */
-	}
-
-	/*
-	 * If we gave the user some bytes, update the access time.
-	 */
-	if (count)
-		file_accessed(file);
-	
-	return (count ? count : retval);
+	/* we don't use timers anymore, we just use the current time */
 }
 
 static ssize_t
 urandom_read(struct file * file, char __user * buf,
 		      size_t nbytes, loff_t *ppos)
 {
-	return extract_entropy(sec_random_state, buf, nbytes,
+	return extract_entropy(random_state, buf, nbytes,
 			       EXTRACT_ENTROPY_USER |
 			       EXTRACT_ENTROPY_SECONDARY);
 }
 
+static ssize_t
+random_read(struct file * file, char __user * buf, size_t nbytes, loff_t *ppos)
+{
+	return urandom_read(file, buf, nbytes, ppos);
+}
+
 static unsigned int
 random_poll(struct file *file, poll_table * wait)
 {
-	unsigned int mask;
-
-	poll_wait(file, &random_read_wait, wait);
-	poll_wait(file, &random_write_wait, wait);
-	mask = 0;
-	if (random_state->entropy_count >= random_read_wakeup_thresh)
-		mask |= POLLIN | POLLRDNORM;
-	if (random_state->entropy_count < random_write_wakeup_thresh)
-		mask |= POLLOUT | POLLWRNORM;
-	return mask;
+	return POLLIN | POLLRDNORM  |  POLLOUT | POLLWRNORM;
 }
 
 static ssize_t
@@ -1701,12 +963,13 @@
 	int		ret = 0;
 	size_t		bytes;
 	__u32 		buf[16];
-	const char 	__user *p = buffer;
+	const char __user	*p = buffer;
 	size_t		c = count;
 
 	while (c > 0) {
 		bytes = min(c, sizeof(buf));
 
+DEBUG_PRINTK("random_write() %p, %p, %u\n", &buf, p, bytes);
 		bytes -= copy_from_user(&buf, p, bytes);
 		if (!bytes) {
 			ret = -EFAULT;
@@ -1730,67 +993,25 @@
 random_ioctl(struct inode * inode, struct file * file,
 	     unsigned int cmd, unsigned long arg)
 {
-	int *tmp, size, ent_count;
-	int __user *p = (int __user *)arg;
+	int size, ent_count;
+	int __user *p = (int __user *) arg;
 	int retval;
-	unsigned long flags;
 	
 	switch (cmd) {
 	case RNDGETENTCNT:
-		ent_count = random_state->entropy_count;
-		if (put_user(ent_count, p))
+		if (put_user(random_entropy_count, p))
 			return -EFAULT;
 		return 0;
 	case RNDADDTOENTCNT:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EPERM;
-		if (get_user(ent_count, p))
-			return -EFAULT;
-		credit_entropy_store(random_state, ent_count);
-		/*
-		 * Wake up waiting processes if we have enough
-		 * entropy.
-		 */
-		if (random_state->entropy_count >= random_read_wakeup_thresh)
-			wake_up_interruptible(&random_read_wait);
+		/* entropy accounting removed. */
 		return 0;
 	case RNDGETPOOL:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EPERM;
-		if (get_user(size, p) ||
-		    put_user(random_state->poolinfo.poolwords, p++))
-			return -EFAULT;
-		if (size < 0)
-			return -EFAULT;
-		if (size > random_state->poolinfo.poolwords)
-			size = random_state->poolinfo.poolwords;
-
-		/* prepare to atomically snapshot pool */
-
-		tmp = kmalloc(size * sizeof(__u32), GFP_KERNEL);
-
-		if (!tmp)
-			return -ENOMEM;
-
-		spin_lock_irqsave(&random_state->lock, flags);
-		ent_count = random_state->entropy_count;
-		memcpy(tmp, random_state->pool, size * sizeof(__u32));
-		spin_unlock_irqrestore(&random_state->lock, flags);
-
-		if (!copy_to_user(p, tmp, size * sizeof(__u32))) {
-			kfree(tmp);
-			return -EFAULT;
-		}
-
-		kfree(tmp);
-
-		if(put_user(ent_count, p++))
-			return -EFAULT;
-
+		/* jlcooke: never get the raw pool!!! */
 		return 0;
 	case RNDADDENTROPY:
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;
+		p = (int *) arg;
 		if (get_user(ent_count, p++))
 			return -EFAULT;
 		if (ent_count < 0)
@@ -1801,25 +1022,12 @@
 				      size, &file->f_pos);
 		if (retval < 0)
 			return retval;
-		credit_entropy_store(random_state, ent_count);
-		/*
-		 * Wake up waiting processes if we have enough
-		 * entropy.
-		 */
-		if (random_state->entropy_count >= random_read_wakeup_thresh)
-			wake_up_interruptible(&random_read_wait);
 		return 0;
 	case RNDZAPENTCNT:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EPERM;
-		random_state->entropy_count = 0;
+		/* entropy accounting removed. */
 		return 0;
 	case RNDCLEARPOOL:
-		/* Clear the entropy pool and associated counters. */
-		if (!capable(CAP_SYS_ADMIN))
-			return -EPERM;
-		clear_entropy_store(random_state);
-		init_std_data(random_state);
+		/* jlcooke: this is maddness! Never clear the entropy pool */
 		return 0;
 	default:
 		return -EINVAL;
@@ -1875,71 +1083,111 @@
 static int min_write_thresh, max_write_thresh;
 static char sysctl_bootid[16];
 
-/*
- * This function handles a request from the user to change the pool size 
- * of the primary entropy store.
- */
-static int change_poolsize(int poolsize)
-{
-	struct entropy_store	*new_store, *old_store;
-	int			ret;
-	
-	if ((ret = create_entropy_store(poolsize, &new_store)))
-		return ret;
-
-	add_entropy_words(new_store, random_state->pool,
-			  random_state->poolinfo.poolwords);
-	credit_entropy_store(new_store, random_state->entropy_count);
-
-	sysctl_init_random(new_store);
-	old_store = random_state;
-	random_state = batch_work.data = new_store;
-	free_entropy_store(old_store);
-	return 0;
-}
-
 static int proc_do_poolsize(ctl_table *table, int write, struct file *filp,
 			    void __user *buffer, size_t *lenp, loff_t *ppos)
 {
-	int	ret;
+	int ret;
 
-	sysctl_poolsize = random_state->poolinfo.POOLBYTES;
+	if (write) {
+		/* you can't change the poolsize, but we'll let you think
+		 * you can for legacy reasons.
+		 */
+		return 0;
+	}
 
+	sysctl_poolsize = (1<<random_state->pool_number) *
+				random_state->pools[0]->__crt_alg->cra_ctxsize;
 	ret = proc_dointvec(table, write, filp, buffer, lenp, ppos);
-	if (ret || !write ||
-	    (sysctl_poolsize == random_state->poolinfo.POOLBYTES))
-		return ret;
 
-	return change_poolsize(sysctl_poolsize);
+	return ret;
 }
 
-static int poolsize_strategy(ctl_table *table, int __user *name, int nlen,
+static int poolsize_strategy(ctl_table *table, int *name, int nlen,
 			     void __user *oldval, size_t __user *oldlenp,
 			     void __user *newval, size_t newlen, void **context)
 {
-	int	len;
-	
-	sysctl_poolsize = random_state->poolinfo.POOLBYTES;
-
-	/*
-	 * We only handle the write case, since the read case gets
-	 * handled by the default handler (and we don't care if the
-	 * write case happens twice; it's harmless).
+	/* you can't set a poolsize strtegy because it doesn't change in
+	 * size anymore
 	 */
-	if (newval && newlen) {
-		len = newlen;
-		if (len > table->maxlen)
-			len = table->maxlen;
-		if (copy_from_user(table->data, newval, len))
-			return -EFAULT;
+	return 0;
+}
+
+static int proc_derive_seed(ctl_table *table, int write, struct file *filp,
+				void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	static unsigned char	*hextab = "0123456789abcdef";
+	static unsigned int	derive_count=0;
+	 /* hex length of derived seed */
+	static unsigned char	buf[(1<<MAXIMUM_POOL_NUMBER) *
+				RANDOM_MAX_DIGEST_SIZE *8/4];
+	unsigned long flags;
+	ctl_table       fake_table;
+	unsigned char   tmp[RANDOM_MAX_DIGEST_SIZE];
+	unsigned int	i,j;
+	struct scatterlist sg[3];
+	int ret;
+	void *p;
+
+DEBUG_PRINTK("proc_derive_seed() 0\n");
+
+	spin_lock_irqsave(&random_state->lock, flags);
+	random_state->pool0_len = 0;
+
+	memset(buf, 0, random_state->pool_number * 2*random_state->digestsize);
+
+	/* the carry-state from pool to pool */
+	memset(tmp, 0, random_state->digestsize);
+
+	for (i=0; i<(1<<random_state->pool_number); i++) {
+		crypto_digest_init(random_state->reseedHash);
+
+		/*
+		 * carry the digest from the previous output so a derive seed
+		 * from a lightly seeded state is indistinguishavble from a
+		 * heavily seeded one
+		 */
+		p = &tmp;
+		sg[0].page = virt_to_page(p);
+		sg[0].offset = offset_in_page(p);
+		sg[0].length = sizeof(tmp);
+
+		/* finalize and digest the i-th pool */
+		crypto_digest_final(random_state->pools[i], tmp);
+		crypto_digest_init(random_state->pools[i]);
+		p = &tmp;
+		sg[1].page = virt_to_page(p);
+		sg[1].offset = offset_in_page(p);
+		sg[1].length = sizeof(tmp);
+
+		/*
+		 * digest in a counter to ensure the final hash can change even if the
+		 * message does not
+		 */
+		p = &derive_count;
+		sg[2].page = virt_to_page(p);
+		sg[2].offset = offset_in_page(p);
+		sg[2].length = sizeof(derive_count);
+
+		crypto_digest_digest(random_state->reseedHash, sg, 3, tmp);
+		for (j=0; j<random_state->digestsize; j++) {
+			buf[2*(i*random_state->digestsize +j)  ] = hextab[ (tmp[j] >> 4) & 0xf ];
+			buf[2*(i*random_state->digestsize +j)+1] = hextab[ (tmp[j]     ) & 0xf ];
+		}
+		derive_count++;
 	}
 
-	if (sysctl_poolsize != random_state->poolinfo.POOLBYTES)
-		return change_poolsize(sysctl_poolsize);
+	spin_unlock_irqrestore(&random_state->lock, flags);
 
-	return 0;
+	fake_table.data = buf;
+	fake_table.maxlen = (1<<random_state->pool_number) *
+				2*random_state->digestsize;
+
+	ret = proc_dostring(&fake_table, write, filp, buffer, lenp, ppos);
+
+	return ret;
 }
 
+
 /*
  * These functions is used to return both the bootid UUID, and random
  * UUID.  The difference is in whether table->data is NULL; if it is,
@@ -1975,7 +1223,7 @@
 	return proc_dostring(&fake_table, write, filp, buffer, lenp, ppos);
 }
 
-static int uuid_strategy(ctl_table *table, int __user *name, int nlen,
+static int uuid_strategy(ctl_table *table, int *name, int nlen,
 			 void __user *oldval, size_t __user *oldlenp,
 			 void __user *newval, size_t newlen, void **context)
 {
@@ -2011,38 +1259,41 @@
 		.procname	= "poolsize",
 		.data		= &sysctl_poolsize,
 		.maxlen		= sizeof(int),
+		/* you can't change the poolsize, but we'll let you think you
+		 * can for legacy reasons.
+		 */
 		.mode		= 0644,
 		.proc_handler	= &proc_do_poolsize,
 		.strategy	= &poolsize_strategy,
 	},
 	{
-		.ctl_name	= RANDOM_ENTROPY_COUNT,
-		.procname	= "entropy_avail",
-		.maxlen		= sizeof(int),
-		.mode		= 0444,
-		.proc_handler	= &proc_dointvec,
-	},
+		.ctl_name       = RANDOM_ENTROPY_COUNT,
+		.procname       = "entropy_avail",
+		.maxlen         = sizeof(int),
+		.mode           = 0444,
+		.proc_handler   = &proc_dointvec,
+        },
 	{
-		.ctl_name	= RANDOM_READ_THRESH,
-		.procname	= "read_wakeup_threshold",
-		.data		= &random_read_wakeup_thresh,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= &proc_dointvec_minmax,
-		.strategy	= &sysctl_intvec,
-		.extra1		= &min_read_thresh,
-		.extra2		= &max_read_thresh,
+		.ctl_name       = RANDOM_READ_THRESH,
+		.procname       = "read_wakeup_threshold",
+		.data           = &random_read_wakeup_thresh,
+		.maxlen         = sizeof(int),
+		.mode           = 0644,
+		.proc_handler   = &proc_dointvec_minmax,
+		.strategy       = &sysctl_intvec,
+		.extra1         = &min_read_thresh,
+		.extra2         = &max_read_thresh,
 	},
 	{
-		.ctl_name	= RANDOM_WRITE_THRESH,
-		.procname	= "write_wakeup_threshold",
-		.data		= &random_write_wakeup_thresh,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= &proc_dointvec_minmax,
-		.strategy	= &sysctl_intvec,
-		.extra1		= &min_write_thresh,
-		.extra2		= &max_write_thresh,
+		.ctl_name       = RANDOM_WRITE_THRESH,
+		.procname       = "write_wakeup_threshold",
+		.data           = &random_write_wakeup_thresh,
+		.maxlen         = sizeof(int),
+		.mode           = 0644,
+		.proc_handler   = &proc_dointvec_minmax,
+		.strategy       = &sysctl_intvec,
+		.extra1         = &min_write_thresh,
+		.extra2         = &max_write_thresh,
 	},
 	{
 		.ctl_name	= RANDOM_BOOT_ID,
@@ -2061,15 +1312,25 @@
 		.proc_handler	= &proc_do_uuid,
 		.strategy	= &uuid_strategy,
 	},
+	{
+		.ctl_name	= RANDOM_DERIVE_SEED,
+		.procname	= "derive_seed",
+		.maxlen		= MAXIMUM_POOL_NUMBER * RANDOM_MAX_DIGEST_SIZE,
+		.mode		= 0400,
+		.proc_handler	= &proc_derive_seed,
+	},
 	{ .ctl_name = 0 }
 };
 
-static void sysctl_init_random(struct entropy_store *random_state)
+static void sysctl_init_random(struct entropy_store *r)
 {
 	min_read_thresh = 8;
 	min_write_thresh = 0;
-	max_read_thresh = max_write_thresh = random_state->poolinfo.POOLBITS;
-	random_table[1].data = &random_state->entropy_count;
+	random_entropy_count =
+	max_read_thresh =
+	max_write_thresh = (1<<r->pool_number) *
+				r->pools[0]->__crt_alg->cra_ctxsize;
+	random_table[1].data = &random_entropy_count;
 }
 #endif 	/* CONFIG_SYSCTL */
 
@@ -2081,135 +1342,23 @@
 
 /*
  * TCP initial sequence number picking.  This uses the random number
- * generator to pick an initial secret value.  This value is hashed
- * along with the TCP endpoint information to provide a unique
- * starting point for each pair of TCP endpoints.  This defeats
- * attacks which rely on guessing the initial TCP sequence number.
- * This algorithm was suggested by Steve Bellovin.
+ * generator to pick an initial secret value.  This value is encrypted
+ * with the TCP endpoint information to provide a unique starting point
+ * for each pair of TCP endpoints.  This defeats attacks which rely on
+ * guessing the initial TCP sequence number.
  *
  * Using a very strong hash was taking an appreciable amount of the total
- * TCP connection establishment time, so this is a weaker hash,
- * compensated for by changing the secret periodically.
+ * TCP connection establishment time, so this now uses AES256
+ * 
+ * openssl spped md4 aes shows aes256 is 2.5 times faster then basic md4 for
+ * the block sizes we're dealing with.
+ * type          16 bytes   64 bytes  256 bytes  1024 bytes  8192 bytes
+ * md4           10708.72k  38240.96k 111170.47k  215872.85k  296828.93k
+ * aes-128 cbc   32121.81k  32678.31k  33119.49k   33221.29k   33210.59k
+ * aes-192 cbc   27915.92k  27868.52k  28418.08k   28677.12k   28721.15k
+ * aes-256 cbc   24599.57k  25142.38k  25381.80k   25474.88k   25392.46k
  */
 
-/* F, G and H are basic MD4 functions: selection, majority, parity */
-#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
-#define G(x, y, z) (((x) & (y)) + (((x) ^ (y)) & (z)))
-#define H(x, y, z) ((x) ^ (y) ^ (z))
-
-/*
- * The generic round function.  The application is so specific that
- * we don't bother protecting all the arguments with parens, as is generally
- * good macro practice, in favor of extra legibility.
- * Rotation is separate from addition to prevent recomputation
- */
-#define ROUND(f, a, b, c, d, x, s)	\
-	(a += f(b, c, d) + x, a = (a << s) | (a >> (32-s)))
-#define K1 0
-#define K2 013240474631UL
-#define K3 015666365641UL
-
-/*
- * Basic cut-down MD4 transform.  Returns only 32 bits of result.
- */
-static __u32 halfMD4Transform (__u32 const buf[4], __u32 const in[8])
-{
-	__u32	a = buf[0], b = buf[1], c = buf[2], d = buf[3];
-
-	/* Round 1 */
-	ROUND(F, a, b, c, d, in[0] + K1,  3);
-	ROUND(F, d, a, b, c, in[1] + K1,  7);
-	ROUND(F, c, d, a, b, in[2] + K1, 11);
-	ROUND(F, b, c, d, a, in[3] + K1, 19);
-	ROUND(F, a, b, c, d, in[4] + K1,  3);
-	ROUND(F, d, a, b, c, in[5] + K1,  7);
-	ROUND(F, c, d, a, b, in[6] + K1, 11);
-	ROUND(F, b, c, d, a, in[7] + K1, 19);
-
-	/* Round 2 */
-	ROUND(G, a, b, c, d, in[1] + K2,  3);
-	ROUND(G, d, a, b, c, in[3] + K2,  5);
-	ROUND(G, c, d, a, b, in[5] + K2,  9);
-	ROUND(G, b, c, d, a, in[7] + K2, 13);
-	ROUND(G, a, b, c, d, in[0] + K2,  3);
-	ROUND(G, d, a, b, c, in[2] + K2,  5);
-	ROUND(G, c, d, a, b, in[4] + K2,  9);
-	ROUND(G, b, c, d, a, in[6] + K2, 13);
-
-	/* Round 3 */
-	ROUND(H, a, b, c, d, in[3] + K3,  3);
-	ROUND(H, d, a, b, c, in[7] + K3,  9);
-	ROUND(H, c, d, a, b, in[2] + K3, 11);
-	ROUND(H, b, c, d, a, in[6] + K3, 15);
-	ROUND(H, a, b, c, d, in[1] + K3,  3);
-	ROUND(H, d, a, b, c, in[5] + K3,  9);
-	ROUND(H, c, d, a, b, in[0] + K3, 11);
-	ROUND(H, b, c, d, a, in[4] + K3, 15);
-
-	return buf[1] + b;	/* "most hashed" word */
-	/* Alternative: return sum of all words? */
-}
-
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-
-static __u32 twothirdsMD4Transform (__u32 const buf[4], __u32 const in[12])
-{
-	__u32	a = buf[0], b = buf[1], c = buf[2], d = buf[3];
-
-	/* Round 1 */
-	ROUND(F, a, b, c, d, in[ 0] + K1,  3);
-	ROUND(F, d, a, b, c, in[ 1] + K1,  7);
-	ROUND(F, c, d, a, b, in[ 2] + K1, 11);
-	ROUND(F, b, c, d, a, in[ 3] + K1, 19);
-	ROUND(F, a, b, c, d, in[ 4] + K1,  3);
-	ROUND(F, d, a, b, c, in[ 5] + K1,  7);
-	ROUND(F, c, d, a, b, in[ 6] + K1, 11);
-	ROUND(F, b, c, d, a, in[ 7] + K1, 19);
-	ROUND(F, a, b, c, d, in[ 8] + K1,  3);
-	ROUND(F, d, a, b, c, in[ 9] + K1,  7);
-	ROUND(F, c, d, a, b, in[10] + K1, 11);
-	ROUND(F, b, c, d, a, in[11] + K1, 19);
-
-	/* Round 2 */
-	ROUND(G, a, b, c, d, in[ 1] + K2,  3);
-	ROUND(G, d, a, b, c, in[ 3] + K2,  5);
-	ROUND(G, c, d, a, b, in[ 5] + K2,  9);
-	ROUND(G, b, c, d, a, in[ 7] + K2, 13);
-	ROUND(G, a, b, c, d, in[ 9] + K2,  3);
-	ROUND(G, d, a, b, c, in[11] + K2,  5);
-	ROUND(G, c, d, a, b, in[ 0] + K2,  9);
-	ROUND(G, b, c, d, a, in[ 2] + K2, 13);
-	ROUND(G, a, b, c, d, in[ 4] + K2,  3);
-	ROUND(G, d, a, b, c, in[ 6] + K2,  5);
-	ROUND(G, c, d, a, b, in[ 8] + K2,  9);
-	ROUND(G, b, c, d, a, in[10] + K2, 13);
-
-	/* Round 3 */
-	ROUND(H, a, b, c, d, in[ 3] + K3,  3);
-	ROUND(H, d, a, b, c, in[ 7] + K3,  9);
-	ROUND(H, c, d, a, b, in[11] + K3, 11);
-	ROUND(H, b, c, d, a, in[ 2] + K3, 15);
-	ROUND(H, a, b, c, d, in[ 6] + K3,  3);
-	ROUND(H, d, a, b, c, in[10] + K3,  9);
-	ROUND(H, c, d, a, b, in[ 1] + K3, 11);
-	ROUND(H, b, c, d, a, in[ 5] + K3, 15);
-	ROUND(H, a, b, c, d, in[ 9] + K3,  3);
-	ROUND(H, d, a, b, c, in[ 0] + K3,  9);
-	ROUND(H, c, d, a, b, in[ 4] + K3, 11);
-	ROUND(H, b, c, d, a, in[ 8] + K3, 15);
-
-	return buf[1] + b;	/* "most hashed" word */
-	/* Alternative: return sum of all words? */
-}
-#endif
-
-#undef ROUND
-#undef F
-#undef G
-#undef H
-#undef K1
-#undef K2
-#undef K3
 
 /* This should not be decreased so low that ISNs wrap too fast. */
 #define REKEY_INTERVAL	300
@@ -2237,79 +1386,70 @@
 #define HASH_BITS	24
 #define HASH_MASK	( (1<<HASH_BITS)-1 )
 
-static struct keydata {
-	time_t rekey_time;
-	__u32	count;		// already shifted to the final position
-	__u32	secret[12];
-} ____cacheline_aligned ip_keydata[2];
-
 static spinlock_t ip_lock = SPIN_LOCK_UNLOCKED;
-static unsigned int ip_cnt;
 
-static struct keydata *__check_and_rekey(time_t time)
+static __u32 network_random_read32(void)
 {
-	struct keydata *keyptr;
+	static u8			ctr[16];    /* max block size? */
+	static struct scatterlist	sgctr[1];
+	static unsigned int		master_count=0;
+	static time_t			lastRekey=0;
+
+	struct scatterlist sgtmp[1];
+	unsigned int	count;
+	unsigned char	tmp[16];
+	struct timeval	tv;
+
+        rmb();
 	spin_lock_bh(&ip_lock);
-	keyptr = &ip_keydata[ip_cnt&1];
-	if (!keyptr->rekey_time || (time - keyptr->rekey_time) > REKEY_INTERVAL) {
-		keyptr = &ip_keydata[1^(ip_cnt&1)];
-		keyptr->rekey_time = time;
-		get_random_bytes(keyptr->secret, sizeof(keyptr->secret));
-		keyptr->count = (ip_cnt&COUNT_MASK)<<HASH_BITS;
+
+	count = ++master_count;
+	increment_iv(ctr, random_state->blocksize);
+
+	do_gettimeofday(&tv);
+	if (lastRekey==0  || (tv.tv_sec - lastRekey) < REKEY_INTERVAL) {
+		lastRekey = tv.tv_sec;
+
+		sgctr[0].page = virt_to_page(ctr);
+		sgctr[0].offset = offset_in_page(ctr);
+		sgctr[0].length = 16;
+
+		if (!random_state->networkCipher_ready) {
+			u8 secret[32]; /* max key size? */
+			get_random_bytes(secret, random_state->keysize);
+			crypto_cipher_setkey(random_state->networkCipher,
+						(const u8*)secret,
+						random_state->keysize);
+			random_state->networkCipher_ready = 1;
+		}
+
 		mb();
-		ip_cnt++;
-	}
-	spin_unlock_bh(&ip_lock);
-	return keyptr;
-}
+        }
 
-static inline struct keydata *check_and_rekey(time_t time)
-{
-	struct keydata *keyptr = &ip_keydata[ip_cnt&1];
+        spin_unlock_bh(&ip_lock);
 
-	rmb();
-	if (!keyptr->rekey_time || (time - keyptr->rekey_time) > REKEY_INTERVAL) {
-		keyptr = __check_and_rekey(time);
-	}
+	sgtmp[0].page = virt_to_page(tmp);
+	sgtmp[0].offset = offset_in_page(tmp);
+	sgtmp[0].length = random_state->blocksize;
+	/* tmp[]/sg[0] = Enc(Sec, CTR++) */
+	crypto_cipher_encrypt(random_state->networkCipher, sgtmp, sgctr, 1);
+	increment_iv(ctr, random_state->blocksize);
 
-	return keyptr;
+	/* seq# needs to be random-ish, but incresing */
+	return (tmp[0] & COUNT_MASK) + (count << (32-COUNT_BITS));
 }
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 __u32 secure_tcpv6_sequence_number(__u32 *saddr, __u32 *daddr,
 				   __u16 sport, __u16 dport)
 {
-	struct timeval 	tv;
-	__u32		seq;
-	__u32		hash[12];
-	struct keydata *keyptr;
-
-	/* The procedure is the same as for IPv4, but addresses are longer.
-	 * Thus we must use twothirdsMD4Transform.
-	 */
-
-	do_gettimeofday(&tv);	/* We need the usecs below... */
-	keyptr = check_and_rekey(tv.tv_sec);
-
-	memcpy(hash, saddr, 16);
-	hash[4]=(sport << 16) + dport;
-	memcpy(&hash[5],keyptr->secret,sizeof(__u32)*7);
-
-	seq = twothirdsMD4Transform(daddr, hash) & HASH_MASK;
-	seq += keyptr->count;
-	seq += tv.tv_usec + tv.tv_sec*1000000;
-
-	return seq;
+	return network_random_read32();
 }
 EXPORT_SYMBOL(secure_tcpv6_sequence_number);
 
 __u32 secure_ipv6_id(__u32 *daddr)
 {
-	struct keydata *keyptr;
-
-	keyptr = check_and_rekey(get_seconds());
-
-	return halfMD4Transform(daddr, keyptr->secret);
+	return network_random_read32();
 }
 
 EXPORT_SYMBOL(secure_ipv6_id);
@@ -2319,75 +1459,20 @@
 __u32 secure_tcp_sequence_number(__u32 saddr, __u32 daddr,
 				 __u16 sport, __u16 dport)
 {
-	struct timeval 	tv;
-	__u32		seq;
-	__u32	hash[4];
-	struct keydata *keyptr;
-
-	/*
-	 * Pick a random secret every REKEY_INTERVAL seconds.
-	 */
-	do_gettimeofday(&tv);	/* We need the usecs below... */
-	keyptr = check_and_rekey(tv.tv_sec);
-
-	/*
-	 *  Pick a unique starting offset for each TCP connection endpoints
-	 *  (saddr, daddr, sport, dport).
-	 *  Note that the words are placed into the starting vector, which is 
-	 *  then mixed with a partial MD4 over random data.
-	 */
-	hash[0]=saddr;
-	hash[1]=daddr;
-	hash[2]=(sport << 16) + dport;
-	hash[3]=keyptr->secret[11];
-
-	seq = halfMD4Transform(hash, keyptr->secret) & HASH_MASK;
-	seq += keyptr->count;
-	/*
-	 *	As close as possible to RFC 793, which
-	 *	suggests using a 250 kHz clock.
-	 *	Further reading shows this assumes 2 Mb/s networks.
-	 *	For 10 Mb/s Ethernet, a 1 MHz clock is appropriate.
-	 *	That's funny, Linux has one built in!  Use it!
-	 *	(Networks are faster now - should this be increased?)
-	 */
-	seq += tv.tv_usec + tv.tv_sec*1000000;
-#if 0
-	printk("init_seq(%lx, %lx, %d, %d) = %d\n",
-	       saddr, daddr, sport, dport, seq);
-#endif
-	return seq;
+	return network_random_read32();
 }
 
 EXPORT_SYMBOL(secure_tcp_sequence_number);
 
-/*  The code below is shamelessly stolen from secure_tcp_sequence_number().
- *  All blames to Andrey V. Savochkin <saw@xxxxxx>.
- */
 __u32 secure_ip_id(__u32 daddr)
 {
-	struct keydata *keyptr;
-	__u32 hash[4];
-
-	keyptr = check_and_rekey(get_seconds());
-
-	/*
-	 *  Pick a unique starting offset for each IP destination.
-	 *  The dest ip address is placed in the starting vector,
-	 *  which is then hashed with random data.
-	 */
-	hash[0] = daddr;
-	hash[1] = keyptr->secret[9];
-	hash[2] = keyptr->secret[10];
-	hash[3] = keyptr->secret[11];
-
-	return halfMD4Transform(hash, keyptr->secret);
+	return network_random_read32();
 }
 
 #ifdef CONFIG_SYN_COOKIES
 /*
  * Secure SYN cookie computation. This is the algorithm worked out by
- * Dan Bernstein and Eric Schenk.
+ * Jean-Luc Cooke
  *
  * For linux I implement the 1 minute counter by looking at the jiffies clock.
  * The count is passed in as a parameter, so this code doesn't much care.
@@ -2396,50 +1481,54 @@
 #define COOKIEBITS 24	/* Upper bits store count */
 #define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1)
 
-static int	syncookie_init;
-static __u32	syncookie_secret[2][16-3+HASH_BUFFER_SIZE];
-
 __u32 secure_tcp_syn_cookie(__u32 saddr, __u32 daddr, __u16 sport,
 		__u16 dport, __u32 sseq, __u32 count, __u32 data)
 {
-	__u32 	tmp[16 + HASH_BUFFER_SIZE + HASH_EXTRA_SIZE];
-	__u32	seq;
-
-	/*
-	 * Pick two random secrets the first time we need a cookie.
-	 */
-	if (syncookie_init == 0) {
-		get_random_bytes(syncookie_secret, sizeof(syncookie_secret));
-		syncookie_init = 1;
-	}
+	struct scatterlist sg[1];
+	__u32	tmp[4];
 
 	/*
 	 * Compute the secure sequence number.
-	 * The output should be:
-   	 *   HASH(sec1,saddr,sport,daddr,dport,sec1) + sseq + (count * 2^24)
-	 *      + (HASH(sec2,saddr,sport,daddr,dport,count,sec2) % 2^24).
-	 * Where sseq is their sequence number and count increases every
-	 * minute by 1.
-	 * As an extra hack, we add a small "data" value that encodes the
-	 * MSS into the second hash value.
+	 * 
+	 * Output is the 32bit tag of a CBC-MAC of PT={count,0,0,0} with IV={addr,daddr,sport|dport,sseq}
+	 *   cookie = <8bit count> || truncate_24bit( Encrypt(Sec, {saddr,daddr,sport|dport,sseq}) )
+	 * 
+	 * DJB wrote (http://cr.yp.to/syncookies/archive) about how to do this with hash algorithms
+	 * - we can replace two SHA1s used in the previous kernel with two AESs and make things 3x faster
+	 * - I'd like to propose we remove the use of two whittenings with a single operation since we
+	 *   were only using addition modulo 2^32 of all these values anyways.  Not to mention the hashs
+	 *   differ only in that the second processes more data... why drop the first hash?  We did learn
+	 *   that addition is commutative and associative long ago.
+	 * - by replacing two SHA1s and addition modulo 2^32 with encryption of a 32bit value using AES-CTR
+	 *   we've made it 1,000,000,000 times easier to understand what is going on.
+	 * - Todo: we should rekey the cipher peridoically... if we do this, some packets will now fail 
+	 *   our checking system... is this ok?  How can we get around this?  Rekey's would ideally happen
+	 *   once per minute (6 million TCP connections per minute is a unrealistic enough security margin)
 	 */
 
-	memcpy(tmp+3, syncookie_secret[0], sizeof(syncookie_secret[0]));
-	tmp[0]=saddr;
-	tmp[1]=daddr;
-	tmp[2]=(sport << 16) + dport;
-	HASH_TRANSFORM(tmp+16, tmp);
-	seq = tmp[17] + sseq + (count << COOKIEBITS);
-
-	memcpy(tmp+3, syncookie_secret[1], sizeof(syncookie_secret[1]));
-	tmp[0]=saddr;
-	tmp[1]=daddr;
-	tmp[2]=(sport << 16) + dport;
-	tmp[3] = count;	/* minute counter */
-	HASH_TRANSFORM(tmp+16, tmp);
+	tmp[0] = saddr;
+	tmp[1] = daddr;
+	tmp[2] = (sport << 16) + dport;
+	tmp[3] = sseq;
+
+	sg[0].page = virt_to_page(tmp);
+	sg[0].offset = offset_in_page(tmp);
+	sg[0].length = 16;
+	if (!random_state->networkCipher_ready) {
+		u8 secret[32];
+		get_random_bytes(secret, sizeof(secret));
+		if (crypto_cipher_setkey(random_state->networkCipher,
+					secret, random_state->keysize)) {
+			return 0;
+		}
+		random_state->networkCipher_ready = 1;
+	}
+	/* tmp[]/sg[0] = Enc(Sec, {saddr,daddr,sport|dport,sseq}) */
+	crypto_cipher_encrypt(random_state->networkCipher, sg, sg, 1);
 
-	/* Add in the second hash and the data */
-	return seq + ((tmp[17] + data) & COOKIEMASK);
+	/* cookie = CTR encrypt of 8-bit-count and 24-bit-data */
+	return tmp[0] ^ ( (count << COOKIEBITS) |
+			(data >> (sizeof(__u32)*8-COOKIEBITS)) );
 }
 
 /*
@@ -2454,32 +1543,32 @@
 __u32 check_tcp_syn_cookie(__u32 cookie, __u32 saddr, __u32 daddr, __u16 sport,
 		__u16 dport, __u32 sseq, __u32 count, __u32 maxdiff)
 {
-	__u32 	tmp[16 + HASH_BUFFER_SIZE + HASH_EXTRA_SIZE];
-	__u32	diff;
+	struct scatterlist sg[1];
+	__u32 tmp[4], thiscount, diff;
 
-	if (syncookie_init == 0)
+	if (random_state == NULL  ||  !random_state->networkCipher_ready)
 		return (__u32)-1;	/* Well, duh! */
 
-	/* Strip away the layers from the cookie */
-	memcpy(tmp+3, syncookie_secret[0], sizeof(syncookie_secret[0]));
-	tmp[0]=saddr;
-	tmp[1]=daddr;
-	tmp[2]=(sport << 16) + dport;
-	HASH_TRANSFORM(tmp+16, tmp);
-	cookie -= tmp[17] + sseq;
-	/* Cookie is now reduced to (count * 2^24) ^ (hash % 2^24) */
-
-	diff = (count - (cookie >> COOKIEBITS)) & ((__u32)-1 >> COOKIEBITS);
-	if (diff >= maxdiff)
-		return (__u32)-1;
-
-	memcpy(tmp+3, syncookie_secret[1], sizeof(syncookie_secret[1]));
 	tmp[0] = saddr;
 	tmp[1] = daddr;
 	tmp[2] = (sport << 16) + dport;
-	tmp[3] = count - diff;	/* minute counter */
-	HASH_TRANSFORM(tmp+16, tmp);
+	tmp[3] = sseq;
+	sg[0].page = virt_to_page(tmp);
+	sg[0].offset = offset_in_page(tmp);
+	sg[0].length = 16;
+	crypto_cipher_encrypt(random_state->networkCipher, sg, sg, 1);
+
+	/* CTR decrypt the cookie */
+	cookie ^= tmp[0]; 
+
+	/* top 8 bits are 'count' */
+	thiscount = cookie >> COOKIEBITS; 
+
+	diff = count - thiscount;
+	if (diff >= maxdiff)
+		return (__u32)-1;
 
-	return (cookie - tmp[17]) & COOKIEMASK;	/* Leaving the data behind */
+	/* bottom 24 bits are 'data' */
+	return cookie >> (sizeof(__u32)*8-COOKIEBITS);
 }
 #endif