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-rw-r--r--src/rng/randpool/randpool.cpp140
-rw-r--r--src/rng/randpool/randpool.h22
2 files changed, 67 insertions, 95 deletions
diff --git a/src/rng/randpool/randpool.cpp b/src/rng/randpool/randpool.cpp
index e35ee22ca..594916a84 100644
--- a/src/rng/randpool/randpool.cpp
+++ b/src/rng/randpool/randpool.cpp
@@ -1,7 +1,7 @@
-/*************************************************
-* Randpool Source File *
-* (C) 1999-2008 Jack Lloyd *
-*************************************************/
+/*
+* Randpool Source File
+* (C) 1999-2009 Jack Lloyd
+*/
#include <botan/randpool.h>
#include <botan/loadstor.h>
@@ -14,9 +14,9 @@ namespace Botan {
namespace {
-/*************************************************
-* PRF based on a MAC *
-*************************************************/
+/**
+* PRF based on a MAC
+*/
enum RANDPOOL_PRF_TAG {
CIPHER_KEY = 0,
MAC_KEY = 1,
@@ -25,14 +25,14 @@ enum RANDPOOL_PRF_TAG {
}
-/*************************************************
-* Generate a buffer of random bytes *
-*************************************************/
+/**
+* Generate a buffer of random bytes
+*/
void Randpool::randomize(byte out[], u32bit length)
{
if(!is_seeded())
{
- reseed();
+ reseed(8 * mac->OUTPUT_LENGTH);
if(!is_seeded())
throw PRNG_Unseeded(name());
@@ -49,15 +49,15 @@ void Randpool::randomize(byte out[], u32bit length)
}
}
-/*************************************************
-* Refill the output buffer *
-*************************************************/
+/**
+* Refill the output buffer
+*/
void Randpool::update_buffer()
{
const u64bit timestamp = system_time();
- for(u32bit j = 0; j != counter.size(); ++j)
- if(++counter[j])
+ for(u32bit i = 0; i != counter.size(); ++i)
+ if(++counter[i])
break;
store_be(timestamp, counter + 4);
@@ -65,17 +65,17 @@ void Randpool::update_buffer()
mac->update(counter, counter.size());
SecureVector<byte> mac_val = mac->final();
- for(u32bit j = 0; j != mac_val.size(); ++j)
- buffer[j % buffer.size()] ^= mac_val[j];
+ for(u32bit i = 0; i != mac_val.size(); ++i)
+ buffer[i % buffer.size()] ^= mac_val[i];
cipher->encrypt(buffer);
if(counter[0] % ITERATIONS_BEFORE_RESEED == 0)
mix_pool();
}
-/*************************************************
-* Mix the entropy pool *
-*************************************************/
+/**
+* Mix the entropy pool
+*/
void Randpool::mix_pool()
{
const u32bit BLOCK_SIZE = cipher->BLOCK_SIZE;
@@ -90,10 +90,10 @@ void Randpool::mix_pool()
xor_buf(pool, buffer, BLOCK_SIZE);
cipher->encrypt(pool);
- for(u32bit j = 1; j != POOL_BLOCKS; ++j)
+ for(u32bit i = 1; i != POOL_BLOCKS; ++i)
{
- const byte* previous_block = pool + BLOCK_SIZE*(j-1);
- byte* this_block = pool + BLOCK_SIZE*j;
+ const byte* previous_block = pool + BLOCK_SIZE*(i-1);
+ byte* this_block = pool + BLOCK_SIZE*i;
xor_buf(this_block, previous_block, BLOCK_SIZE);
cipher->encrypt(this_block);
}
@@ -101,61 +101,33 @@ void Randpool::mix_pool()
update_buffer();
}
-/*************************************************
-* Reseed the internal state *
-*************************************************/
-void Randpool::reseed()
+/**
+* Reseed the internal state
+*/
+void Randpool::reseed(u32bit poll_bits)
{
- SecureVector<byte> buffer(128);
+ Entropy_Accumulator accum(poll_bits);
- u32bit entropy_est = 0;
-
- /*
- When we reseed, assume we get 1 bit per byte sampled.
-
- This class used to perform entropy estimation, but what we really
- want to measure is the conditional entropy of the data with respect
- to an unknown attacker with unknown capabilities. For this reason
- making any sort of sane estimate is impossible. See also
- "Boaz Barak, Shai Halevi: A model and architecture for
- pseudo-random generation with applications to /dev/random. ACM
- Conference on Computer and Communications Security 2005."
- */
-
- // First do a fast poll of all sources (no matter what)
- for(u32bit j = 0; j != entropy_sources.size(); ++j)
+ for(u32bit i = 0; i != entropy_sources.size(); ++i)
{
- u32bit got = entropy_sources[j]->fast_poll(buffer, buffer.size());
-
- mac->update(buffer, got);
- entropy_est += got;
- buffer.clear();
- }
+ entropy_sources[i]->poll(accum);
- // Then do a slow poll, until we think we have got enough entropy
- for(u32bit j = 0; j != entropy_sources.size(); ++j)
- {
- u32bit got = entropy_sources[j]->slow_poll(buffer, buffer.size());
-
- mac->update(buffer, got);
- entropy_est += got;
-
- if(entropy_est > 512)
+ if(accum.polling_goal_achieved())
break;
- buffer.clear();
}
- SecureVector<byte> mac_val = mac->final();
+ SecureVector<byte> mac_val = mac->process(accum.get_entropy_buffer());
xor_buf(pool, mac_val, mac_val.size());
mix_pool();
- entropy = std::min<u32bit>(entropy + entropy_est, 8 * mac_val.size());
+ entropy = std::min<u32bit>(entropy + accum.bits_collected(),
+ 8 * mac_val.size());
}
-/*************************************************
-* Add user-supplied entropy *
-*************************************************/
+/**
+* Add user-supplied entropy
+*/
void Randpool::add_entropy(const byte input[], u32bit length)
{
SecureVector<byte> mac_val = mac->process(input, length);
@@ -166,25 +138,25 @@ void Randpool::add_entropy(const byte input[], u32bit length)
entropy = std::min<u32bit>(entropy + length, 8 * mac_val.size());
}
-/*************************************************
-* Add another entropy source to the list *
-*************************************************/
+/**
+* Add another entropy source to the list
+*/
void Randpool::add_entropy_source(EntropySource* src)
{
entropy_sources.push_back(src);
}
-/*************************************************
-* Check if the the pool is seeded *
-*************************************************/
+/**
+* Check if the the pool is seeded
+*/
bool Randpool::is_seeded() const
{
return (entropy >= 7 * mac->OUTPUT_LENGTH);
}
-/*************************************************
-* Clear memory of sensitive data *
-*************************************************/
+/**
+* Clear memory of sensitive data
+*/
void Randpool::clear() throw()
{
cipher->clear();
@@ -195,17 +167,17 @@ void Randpool::clear() throw()
entropy = 0;
}
-/*************************************************
-* Return the name of this type *
-*************************************************/
+/**
+* Return the name of this type
+*/
std::string Randpool::name() const
{
return "Randpool(" + cipher->name() + "," + mac->name() + ")";
}
-/*************************************************
-* Randpool Constructor *
-*************************************************/
+/**
+* Randpool Constructor
+*/
Randpool::Randpool(BlockCipher* cipher_in,
MessageAuthenticationCode* mac_in,
u32bit pool_blocks,
@@ -234,9 +206,9 @@ Randpool::Randpool(BlockCipher* cipher_in,
entropy = 0;
}
-/*************************************************
-* Randpool Destructor *
-*************************************************/
+/**
+* Randpool Destructor
+*/
Randpool::~Randpool()
{
delete cipher;
diff --git a/src/rng/randpool/randpool.h b/src/rng/randpool/randpool.h
index f6bae9d52..46683934e 100644
--- a/src/rng/randpool/randpool.h
+++ b/src/rng/randpool/randpool.h
@@ -1,7 +1,7 @@
-/*************************************************
-* Randpool Header File *
-* (C) 1999-2008 Jack Lloyd *
-*************************************************/
+/*
+* Randpool Header File
+* (C) 1999-2008 Jack Lloyd
+*/
#ifndef BOTAN_RANDPOOL_H__
#define BOTAN_RANDPOOL_H__
@@ -13,9 +13,9 @@
namespace Botan {
-/*************************************************
-* Randpool *
-*************************************************/
+/**
+* Randpool
+*/
class BOTAN_DLL Randpool : public RandomNumberGenerator
{
public:
@@ -24,11 +24,11 @@ class BOTAN_DLL Randpool : public RandomNumberGenerator
void clear() throw();
std::string name() const;
- void reseed();
- void add_entropy_source(EntropySource*);
- void add_entropy(const byte[], u32bit);
+ void reseed(u32bit bits_to_collect);
+ void add_entropy_source(EntropySource* es);
+ void add_entropy(const byte input[], u32bit length);
- Randpool(BlockCipher*, MessageAuthenticationCode*,
+ Randpool(BlockCipher* cipher, MessageAuthenticationCode* mac,
u32bit pool_blocks = 32,
u32bit iterations_before_reseed = 128);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-30 02:29:35 +0000