gecko-dev/security/nss/lib/freebl/drbg.c

951 строка
36 KiB
C

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifdef FREEBL_NO_DEPEND
#include "stubs.h"
#endif
#include "prerror.h"
#include "secerr.h"
#include "prtypes.h"
#include "prinit.h"
#include "blapi.h"
#include "blapii.h"
#include "nssilock.h"
#include "secitem.h"
#include "sha_fast.h"
#include "sha256.h"
#include "secrng.h" /* for RNG_SystemRNG() */
#include "secmpi.h"
/* PRNG_SEEDLEN defined in NIST SP 800-90 section 10.1
* for SHA-1, SHA-224, and SHA-256 it's 440 bits.
* for SHA-384 and SHA-512 it's 888 bits */
#define PRNG_SEEDLEN (440 / PR_BITS_PER_BYTE)
#define PRNG_MAX_ADDITIONAL_BYTES PR_INT64(0x100000000)
/* 2^35 bits or 2^32 bytes */
#define PRNG_MAX_REQUEST_SIZE 0x10000 /* 2^19 bits or 2^16 bytes */
#define PRNG_ADDITONAL_DATA_CACHE_SIZE (8 * 1024) /* must be less than \
* PRNG_MAX_ADDITIONAL_BYTES \
*/
/* RESEED_COUNT is how many calls to the prng before we need to reseed
* under normal NIST rules, you must return an error. In the NSS case, we
* self-reseed with RNG_SystemRNG(). Count can be a large number. For code
* simplicity, we specify count with 2 components: RESEED_BYTE (which is
* the same as LOG256(RESEED_COUNT)) and RESEED_VALUE (which is the same as
* RESEED_COUNT / (256 ^ RESEED_BYTE)). Another way to look at this is
* RESEED_COUNT = RESEED_VALUE * (256 ^ RESEED_BYTE). For Hash based DRBG
* we use the maximum count value, 2^48, or RESEED_BYTE=6 and RESEED_VALUE=1
*/
#define RESEED_BYTE 6
#define RESEED_VALUE 1
#define PRNG_RESET_RESEED_COUNT(rng) \
PORT_Memset((rng)->reseed_counter, 0, sizeof(rng)->reseed_counter); \
(rng)->reseed_counter[RESEED_BYTE] = 1;
/*
* The actual values of this enum are specified in SP 800-90, 10.1.1.*
* The spec does not name the types, it only uses bare values
*/
typedef enum {
prngCGenerateType = 0, /* used when creating a new 'C' */
prngReseedType = 1, /* used in reseeding */
prngAdditionalDataType = 2, /* used in mixing additional data */
prngGenerateByteType = 3 /* used when mixing internal state while
* generating bytes */
} prngVTypes;
/*
* Global RNG context
*/
struct RNGContextStr {
PZLock *lock; /* Lock to serialize access to global rng */
/*
* NOTE, a number of steps in the drbg algorithm need to hash
* V_type || V. The code, therefore, depends on the V array following
* immediately after V_type to avoid extra copies. To accomplish this
* in a way that compiliers can't perturb, we declare V_type and V
* as a V_Data array and reference them by macros */
PRUint8 V_Data[PRNG_SEEDLEN + 1]; /* internal state variables */
#define V_type V_Data[0]
#define V(rng) (((rng)->V_Data) + 1)
#define VSize(rng) ((sizeof(rng)->V_Data) - 1)
PRUint8 C[PRNG_SEEDLEN]; /* internal state variables */
PRUint8 lastOutput[SHA256_LENGTH]; /* for continuous rng checking */
/* If we get calls for the PRNG to return less than the length of our
* hash, we extend the request for a full hash (since we'll be doing
* the full hash anyway). Future requests for random numbers are fulfilled
* from the remainder of the bytes we generated. Requests for bytes longer
* than the hash size are fulfilled directly from the HashGen function
* of the random number generator. */
PRUint8 reseed_counter[RESEED_BYTE + 1]; /* number of requests since the
* last reseed. Need only be
* big enough to hold the whole
* reseed count */
PRUint8 data[SHA256_LENGTH]; /* when we request less than a block
* save the rest of the rng output for
* another partial block */
PRUint8 dataAvail; /* # bytes of output available in our cache,
* [0...SHA256_LENGTH] */
/* store additional data that has been shovelled off to us by
* RNG_RandomUpdate. */
PRUint8 additionalDataCache[PRNG_ADDITONAL_DATA_CACHE_SIZE];
PRUint32 additionalAvail;
PRBool isValid; /* false if RNG reaches an invalid state */
PRBool isKatTest; /* true if running NIST PRNG KAT tests */
};
typedef struct RNGContextStr RNGContext;
static RNGContext *globalrng = NULL;
static RNGContext theGlobalRng;
/*
* The next several functions are derived from the NIST SP 800-90
* spec. In these functions, an attempt was made to use names consistent
* with the names in the spec, even if they differ from normal NSS usage.
*/
/*
* Hash Derive function defined in NISP SP 800-90 Section 10.4.1.
* This function is used in the Instantiate and Reseed functions.
*
* NOTE: requested_bytes cannot overlap with input_string_1 or input_string_2.
* input_string_1 and input_string_2 are logically concatentated.
* input_string_1 must be supplied.
* if input_string_2 is not supplied, NULL should be passed for this parameter.
*/
static SECStatus
prng_Hash_df(PRUint8 *requested_bytes, unsigned int no_of_bytes_to_return,
const PRUint8 *input_string_1, unsigned int input_string_1_len,
const PRUint8 *input_string_2, unsigned int input_string_2_len)
{
SHA256Context ctx;
PRUint32 tmp;
PRUint8 counter;
tmp = SHA_HTONL(no_of_bytes_to_return * 8);
for (counter = 1; no_of_bytes_to_return > 0; counter++) {
unsigned int hash_return_len;
SHA256_Begin(&ctx);
SHA256_Update(&ctx, &counter, 1);
SHA256_Update(&ctx, (unsigned char *)&tmp, sizeof tmp);
SHA256_Update(&ctx, input_string_1, input_string_1_len);
if (input_string_2) {
SHA256_Update(&ctx, input_string_2, input_string_2_len);
}
SHA256_End(&ctx, requested_bytes, &hash_return_len,
no_of_bytes_to_return);
requested_bytes += hash_return_len;
no_of_bytes_to_return -= hash_return_len;
}
return SECSuccess;
}
/*
* Hash_DRBG Instantiate NIST SP 800-90 10.1.1.2
*
* NOTE: bytes & len are entropy || nonce || personalization_string. In
* normal operation, NSS calculates them all together in a single call.
*/
static SECStatus
prng_instantiate(RNGContext *rng, const PRUint8 *bytes, unsigned int len)
{
if (!rng->isKatTest && len < PRNG_SEEDLEN) {
/* If the seedlen is too small, it's probably because we failed to get
* enough random data.
* This is stricter than NIST SP800-90A requires. Don't enforce it for
* tests. */
PORT_SetError(SEC_ERROR_NEED_RANDOM);
return SECFailure;
}
prng_Hash_df(V(rng), VSize(rng), bytes, len, NULL, 0);
rng->V_type = prngCGenerateType;
prng_Hash_df(rng->C, sizeof rng->C, rng->V_Data, sizeof rng->V_Data, NULL, 0);
PRNG_RESET_RESEED_COUNT(rng)
return SECSuccess;
}
/*
* Update the global random number generator with more seeding
* material. Use the Hash_DRBG reseed algorithm from NIST SP-800-90
* section 10.1.1.3
*
* If entropy is NULL, it is fetched from the noise generator.
*/
static SECStatus
prng_reseed(RNGContext *rng, const PRUint8 *entropy, unsigned int entropy_len,
const PRUint8 *additional_input, unsigned int additional_input_len)
{
PRUint8 noiseData[(sizeof rng->V_Data) + PRNG_SEEDLEN];
PRUint8 *noise = &noiseData[0];
/* if entropy wasn't supplied, fetch it. (normal operation case) */
if (entropy == NULL) {
entropy_len = (unsigned int)RNG_SystemRNG(
&noiseData[sizeof rng->V_Data], PRNG_SEEDLEN);
} else {
/* NOTE: this code is only available for testing, not to applications */
/* if entropy was too big for the stack variable, get it from malloc */
if (entropy_len > PRNG_SEEDLEN) {
noise = PORT_Alloc(entropy_len + (sizeof rng->V_Data));
if (noise == NULL) {
return SECFailure;
}
}
PORT_Memcpy(&noise[sizeof rng->V_Data], entropy, entropy_len);
}
if (entropy_len < 256 / PR_BITS_PER_BYTE) {
/* noise == &noiseData[0] at this point, so nothing to free */
PORT_SetError(SEC_ERROR_NEED_RANDOM);
return SECFailure;
}
rng->V_type = prngReseedType;
PORT_Memcpy(noise, rng->V_Data, sizeof rng->V_Data);
prng_Hash_df(V(rng), VSize(rng), noise, (sizeof rng->V_Data) + entropy_len,
additional_input, additional_input_len);
/* clear potential CSP */
PORT_Memset(noise, 0, (sizeof rng->V_Data) + entropy_len);
rng->V_type = prngCGenerateType;
prng_Hash_df(rng->C, sizeof rng->C, rng->V_Data, sizeof rng->V_Data, NULL, 0);
PRNG_RESET_RESEED_COUNT(rng)
if (noise != &noiseData[0]) {
PORT_Free(noise);
}
return SECSuccess;
}
/*
* SP 800-90 requires we rerun our health tests on reseed
*/
static SECStatus
prng_reseed_test(RNGContext *rng, const PRUint8 *entropy,
unsigned int entropy_len, const PRUint8 *additional_input,
unsigned int additional_input_len)
{
SECStatus rv;
/* do health checks in FIPS mode */
rv = PRNGTEST_RunHealthTests();
if (rv != SECSuccess) {
/* error set by PRNGTEST_RunHealTests() */
rng->isValid = PR_FALSE;
return SECFailure;
}
return prng_reseed(rng, entropy, entropy_len,
additional_input, additional_input_len);
}
/*
* build some fast inline functions for adding.
*/
#define PRNG_ADD_CARRY_ONLY(dest, start, carry) \
{ \
int k1; \
for (k1 = start; carry && k1 >= 0; k1--) { \
carry = !(++dest[k1]); \
} \
}
/*
* NOTE: dest must be an array for the following to work.
*/
#define PRNG_ADD_BITS(dest, dest_len, add, len, carry) \
carry = 0; \
PORT_Assert((dest_len) >= (len)); \
{ \
int k1, k2; \
for (k1 = dest_len - 1, k2 = len - 1; k2 >= 0; --k1, --k2) { \
carry += dest[k1] + add[k2]; \
dest[k1] = (PRUint8)carry; \
carry >>= 8; \
} \
}
#define PRNG_ADD_BITS_AND_CARRY(dest, dest_len, add, len, carry) \
PRNG_ADD_BITS(dest, dest_len, add, len, carry) \
PRNG_ADD_CARRY_ONLY(dest, dest_len - len - 1, carry)
/*
* This function expands the internal state of the prng to fulfill any number
* of bytes we need for this request. We only use this call if we need more
* than can be supplied by a single call to SHA256_HashBuf.
*
* This function is specified in NIST SP 800-90 section 10.1.1.4, Hashgen
*/
static void
prng_Hashgen(RNGContext *rng, PRUint8 *returned_bytes,
unsigned int no_of_returned_bytes)
{
PRUint8 data[VSize(rng)];
PRUint8 thisHash[SHA256_LENGTH];
PRUint8 *lastHash = rng->lastOutput;
PORT_Memcpy(data, V(rng), VSize(rng));
while (no_of_returned_bytes) {
SHA256Context ctx;
unsigned int len;
unsigned int carry;
SHA256_Begin(&ctx);
SHA256_Update(&ctx, data, sizeof data);
SHA256_End(&ctx, thisHash, &len, SHA256_LENGTH);
if (PORT_Memcmp(lastHash, thisHash, len) == 0) {
rng->isValid = PR_FALSE;
break;
}
if (no_of_returned_bytes < SHA256_LENGTH) {
len = no_of_returned_bytes;
}
PORT_Memcpy(returned_bytes, thisHash, len);
lastHash = returned_bytes;
returned_bytes += len;
no_of_returned_bytes -= len;
/* The carry parameter is a bool (increment or not).
* This increments data if no_of_returned_bytes is not zero */
carry = no_of_returned_bytes;
PRNG_ADD_CARRY_ONLY(data, (sizeof data) - 1, carry);
}
PORT_Memcpy(rng->lastOutput, thisHash, SHA256_LENGTH);
PORT_Memset(data, 0, sizeof data);
PORT_Memset(thisHash, 0, sizeof thisHash);
}
/*
* Generates new random bytes and advances the internal prng state.
* additional bytes are only used in algorithm testing.
*
* This function is specified in NIST SP 800-90 section 10.1.1.4
*/
static SECStatus
prng_generateNewBytes(RNGContext *rng,
PRUint8 *returned_bytes, unsigned int no_of_returned_bytes,
const PRUint8 *additional_input,
unsigned int additional_input_len)
{
PRUint8 H[SHA256_LENGTH]; /* both H and w since they
* aren't used concurrently */
unsigned int carry;
if (!rng->isValid) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* This code only triggers during tests, normal
* prng operation does not use additional_input */
if (additional_input) {
SHA256Context ctx;
/* NIST SP 800-90 defines two temporaries in their calculations,
* w and H. These temporaries are the same lengths, and used
* at different times, so we use the following macro to collapse
* them to the same variable, but keeping their unique names for
* easy comparison to the spec */
#define w H
rng->V_type = prngAdditionalDataType;
SHA256_Begin(&ctx);
SHA256_Update(&ctx, rng->V_Data, sizeof rng->V_Data);
SHA256_Update(&ctx, additional_input, additional_input_len);
SHA256_End(&ctx, w, NULL, sizeof w);
PRNG_ADD_BITS_AND_CARRY(V(rng), VSize(rng), w, sizeof w, carry)
PORT_Memset(w, 0, sizeof w);
#undef w
}
if (no_of_returned_bytes == SHA256_LENGTH) {
/* short_cut to hashbuf and a couple of copies and clears */
SHA256_HashBuf(returned_bytes, V(rng), VSize(rng));
/* continuous rng check */
if (memcmp(rng->lastOutput, returned_bytes, SHA256_LENGTH) == 0) {
rng->isValid = PR_FALSE;
}
PORT_Memcpy(rng->lastOutput, returned_bytes, sizeof rng->lastOutput);
} else {
prng_Hashgen(rng, returned_bytes, no_of_returned_bytes);
}
/* advance our internal state... */
rng->V_type = prngGenerateByteType;
SHA256_HashBuf(H, rng->V_Data, sizeof rng->V_Data);
PRNG_ADD_BITS_AND_CARRY(V(rng), VSize(rng), H, sizeof H, carry)
PRNG_ADD_BITS(V(rng), VSize(rng), rng->C, sizeof rng->C, carry);
PRNG_ADD_BITS_AND_CARRY(V(rng), VSize(rng), rng->reseed_counter,
sizeof rng->reseed_counter, carry)
carry = 1;
PRNG_ADD_CARRY_ONLY(rng->reseed_counter, (sizeof rng->reseed_counter) - 1, carry);
/* if the prng failed, don't return any output, signal softoken */
if (!rng->isValid) {
PORT_Memset(returned_bytes, 0, no_of_returned_bytes);
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
return SECSuccess;
}
/* Use NSPR to prevent RNG_RNGInit from being called from separate
* threads, creating a race condition.
*/
static const PRCallOnceType pristineCallOnce;
static PRCallOnceType coRNGInit;
static PRStatus
rng_init(void)
{
PRUint8 bytes[PRNG_SEEDLEN * 2]; /* entropy + nonce */
unsigned int numBytes;
SECStatus rv = SECSuccess;
if (globalrng == NULL) {
/* bytes needs to have enough space to hold
* a SHA256 hash value. Blow up at compile time if this isn't true */
PR_STATIC_ASSERT(sizeof(bytes) >= SHA256_LENGTH);
/* create a new global RNG context */
globalrng = &theGlobalRng;
PORT_Assert(NULL == globalrng->lock);
/* create a lock for it */
globalrng->lock = PZ_NewLock(nssILockOther);
if (globalrng->lock == NULL) {
globalrng = NULL;
PORT_SetError(PR_OUT_OF_MEMORY_ERROR);
return PR_FAILURE;
}
/* Try to get some seed data for the RNG */
numBytes = (unsigned int)RNG_SystemRNG(bytes, sizeof bytes);
PORT_Assert(numBytes == 0 || numBytes == sizeof bytes);
if (numBytes != 0) {
/* if this is our first call, instantiate, otherwise reseed
* prng_instantiate gets a new clean state, we want to mix
* any previous entropy we may have collected */
if (V(globalrng)[0] == 0) {
rv = prng_instantiate(globalrng, bytes, numBytes);
} else {
rv = prng_reseed_test(globalrng, bytes, numBytes, NULL, 0);
}
memset(bytes, 0, numBytes);
} else {
PZ_DestroyLock(globalrng->lock);
globalrng->lock = NULL;
globalrng = NULL;
return PR_FAILURE;
}
if (rv != SECSuccess) {
return PR_FAILURE;
}
/* the RNG is in a valid state */
globalrng->isValid = PR_TRUE;
globalrng->isKatTest = PR_FALSE;
/* fetch one random value so that we can populate rng->oldV for our
* continous random number test. */
prng_generateNewBytes(globalrng, bytes, SHA256_LENGTH, NULL, 0);
/* Fetch more entropy into the PRNG */
RNG_SystemInfoForRNG();
}
return PR_SUCCESS;
}
/*
* Clean up the global RNG context
*/
static void
prng_freeRNGContext(RNGContext *rng)
{
PRUint8 inputhash[VSize(rng) + (sizeof rng->C)];
/* destroy context lock */
SKIP_AFTER_FORK(PZ_DestroyLock(globalrng->lock));
/* zero global RNG context except for C & V to preserve entropy */
prng_Hash_df(inputhash, sizeof rng->C, rng->C, sizeof rng->C, NULL, 0);
prng_Hash_df(&inputhash[sizeof rng->C], VSize(rng), V(rng), VSize(rng),
NULL, 0);
memset(rng, 0, sizeof *rng);
memcpy(rng->C, inputhash, sizeof rng->C);
memcpy(V(rng), &inputhash[sizeof rng->C], VSize(rng));
memset(inputhash, 0, sizeof inputhash);
}
/*
* Public functions
*/
/*
* Initialize the global RNG context and give it some seed input taken
* from the system. This function is thread-safe and will only allow
* the global context to be initialized once. The seed input is likely
* small, so it is imperative that RNG_RandomUpdate() be called with
* additional seed data before the generator is used. A good way to
* provide the generator with additional entropy is to call
* RNG_SystemInfoForRNG(). Note that C_Initialize() does exactly that.
*/
SECStatus
RNG_RNGInit(void)
{
/* Allow only one call to initialize the context */
PR_CallOnce(&coRNGInit, rng_init);
/* Make sure there is a context */
return (globalrng != NULL) ? SECSuccess : SECFailure;
}
/*
** Update the global random number generator with more seeding
** material.
*/
SECStatus
RNG_RandomUpdate(const void *data, size_t bytes)
{
SECStatus rv;
/* Make sure our assumption that size_t is unsigned is true */
PR_STATIC_ASSERT(((size_t)-1) > (size_t)1);
#if defined(NS_PTR_GT_32) || (defined(NSS_USE_64) && !defined(NS_PTR_LE_32))
/*
* NIST 800-90 requires us to verify our inputs. This value can
* come from the application, so we need to make sure it's within the
* spec. The spec says it must be less than 2^32 bytes (2^35 bits).
* This can only happen if size_t is greater than 32 bits (i.e. on
* most 64 bit platforms). The 90% case (perhaps 100% case), size_t
* is less than or equal to 32 bits if the platform is not 64 bits, and
* greater than 32 bits if it is a 64 bit platform. The corner
* cases are handled with explicit defines NS_PTR_GT_32 and NS_PTR_LE_32.
*
* In general, neither NS_PTR_GT_32 nor NS_PTR_LE_32 will need to be
* defined. If you trip over the next two size ASSERTS at compile time,
* you will need to define them for your platform.
*
* if 'sizeof(size_t) > 4' is triggered it means that we were expecting
* sizeof(size_t) to be greater than 4, but it wasn't. Setting
* NS_PTR_LE_32 will correct that mistake.
*
* if 'sizeof(size_t) <= 4' is triggered, it means that we were expecting
* sizeof(size_t) to be less than or equal to 4, but it wasn't. Setting
* NS_PTR_GT_32 will correct that mistake.
*/
PR_STATIC_ASSERT(sizeof(size_t) > 4);
if (bytes > (size_t)PRNG_MAX_ADDITIONAL_BYTES) {
bytes = PRNG_MAX_ADDITIONAL_BYTES;
}
#else
PR_STATIC_ASSERT(sizeof(size_t) <= 4);
#endif
PZ_Lock(globalrng->lock);
/* if we're passed more than our additionalDataCache, simply
* call reseed with that data */
if (bytes > sizeof(globalrng->additionalDataCache)) {
rv = prng_reseed_test(globalrng, NULL, 0, data, (unsigned int)bytes);
/* if we aren't going to fill or overflow the buffer, just cache it */
} else if (bytes < ((sizeof globalrng->additionalDataCache) - globalrng->additionalAvail)) {
PORT_Memcpy(globalrng->additionalDataCache + globalrng->additionalAvail,
data, bytes);
globalrng->additionalAvail += (PRUint32)bytes;
rv = SECSuccess;
} else {
/* we are going to fill or overflow the buffer. In this case we will
* fill the entropy buffer, reseed with it, start a new buffer with the
* remainder. We know the remainder will fit in the buffer because
* we already handled the case where bytes > the size of the buffer.
*/
size_t bufRemain = (sizeof globalrng->additionalDataCache) - globalrng->additionalAvail;
/* fill the rest of the buffer */
if (bufRemain) {
PORT_Memcpy(globalrng->additionalDataCache + globalrng->additionalAvail,
data, bufRemain);
data = ((unsigned char *)data) + bufRemain;
bytes -= bufRemain;
}
/* reseed from buffer */
rv = prng_reseed_test(globalrng, NULL, 0,
globalrng->additionalDataCache,
sizeof globalrng->additionalDataCache);
/* copy the rest into the cache */
PORT_Memcpy(globalrng->additionalDataCache, data, bytes);
globalrng->additionalAvail = (PRUint32)bytes;
}
PZ_Unlock(globalrng->lock);
return rv;
}
/*
** Generate some random bytes, using the global random number generator
** object.
*/
static SECStatus
prng_GenerateGlobalRandomBytes(RNGContext *rng,
void *dest, size_t len)
{
SECStatus rv = SECSuccess;
PRUint8 *output = dest;
/* check for a valid global RNG context */
PORT_Assert(rng != NULL);
if (rng == NULL) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* FIPS limits the amount of entropy available in a single request */
if (len > PRNG_MAX_REQUEST_SIZE) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* --- LOCKED --- */
PZ_Lock(rng->lock);
/* Check the amount of seed data in the generator. If not enough,
* don't produce any data.
*/
if (rng->reseed_counter[0] >= RESEED_VALUE) {
rv = prng_reseed_test(rng, NULL, 0, NULL, 0);
PZ_Unlock(rng->lock);
if (rv != SECSuccess) {
return rv;
}
RNG_SystemInfoForRNG();
PZ_Lock(rng->lock);
}
/*
* see if we have enough bytes to fulfill the request.
*/
if (len <= rng->dataAvail) {
memcpy(output, rng->data + ((sizeof rng->data) - rng->dataAvail), len);
memset(rng->data + ((sizeof rng->data) - rng->dataAvail), 0, len);
rng->dataAvail -= len;
rv = SECSuccess;
/* if we are asking for a small number of bytes, cache the rest of
* the bytes */
} else if (len < sizeof rng->data) {
rv = prng_generateNewBytes(rng, rng->data, sizeof rng->data,
rng->additionalAvail ? rng->additionalDataCache : NULL,
rng->additionalAvail);
rng->additionalAvail = 0;
if (rv == SECSuccess) {
memcpy(output, rng->data, len);
memset(rng->data, 0, len);
rng->dataAvail = (sizeof rng->data) - len;
}
/* we are asking for lots of bytes, just ask the generator to pass them */
} else {
rv = prng_generateNewBytes(rng, output, len,
rng->additionalAvail ? rng->additionalDataCache : NULL,
rng->additionalAvail);
rng->additionalAvail = 0;
}
PZ_Unlock(rng->lock);
/* --- UNLOCKED --- */
return rv;
}
/*
** Generate some random bytes, using the global random number generator
** object.
*/
SECStatus
RNG_GenerateGlobalRandomBytes(void *dest, size_t len)
{
return prng_GenerateGlobalRandomBytes(globalrng, dest, len);
}
void
RNG_RNGShutdown(void)
{
/* check for a valid global RNG context */
PORT_Assert(globalrng != NULL);
if (globalrng == NULL) {
/* Should set a "not initialized" error code. */
PORT_SetError(SEC_ERROR_NO_MEMORY);
return;
}
/* clear */
prng_freeRNGContext(globalrng);
globalrng = NULL;
/* reset the callonce struct to allow a new call to RNG_RNGInit() */
coRNGInit = pristineCallOnce;
}
/*
* Test case interface. used by fips testing and power on self test
*/
/* make sure the test context is separate from the global context, This
* allows us to test the internal random number generator without losing
* entropy we may have previously collected. */
RNGContext testContext;
SECStatus
PRNGTEST_Instantiate_Kat(const PRUint8 *entropy, unsigned int entropy_len,
const PRUint8 *nonce, unsigned int nonce_len,
const PRUint8 *personal_string, unsigned int ps_len)
{
testContext.isKatTest = PR_TRUE;
return PRNGTEST_Instantiate(entropy, entropy_len,
nonce, nonce_len,
personal_string, ps_len);
}
/*
* Test vector API. Use NIST SP 800-90 general interface so one of the
* other NIST SP 800-90 algorithms may be used in the future.
*/
SECStatus
PRNGTEST_Instantiate(const PRUint8 *entropy, unsigned int entropy_len,
const PRUint8 *nonce, unsigned int nonce_len,
const PRUint8 *personal_string, unsigned int ps_len)
{
int bytes_len = entropy_len + nonce_len + ps_len;
PRUint8 *bytes = NULL;
SECStatus rv;
if (entropy_len < 256 / PR_BITS_PER_BYTE) {
PORT_SetError(SEC_ERROR_NEED_RANDOM);
return SECFailure;
}
bytes = PORT_Alloc(bytes_len);
if (bytes == NULL) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
return SECFailure;
}
/* concatenate the various inputs, internally NSS only instantiates with
* a single long string */
PORT_Memcpy(bytes, entropy, entropy_len);
if (nonce) {
PORT_Memcpy(&bytes[entropy_len], nonce, nonce_len);
} else {
PORT_Assert(nonce_len == 0);
}
if (personal_string) {
PORT_Memcpy(&bytes[entropy_len + nonce_len], personal_string, ps_len);
} else {
PORT_Assert(ps_len == 0);
}
rv = prng_instantiate(&testContext, bytes, bytes_len);
PORT_ZFree(bytes, bytes_len);
if (rv == SECFailure) {
return SECFailure;
}
testContext.isValid = PR_TRUE;
return SECSuccess;
}
SECStatus
PRNGTEST_Reseed(const PRUint8 *entropy, unsigned int entropy_len,
const PRUint8 *additional, unsigned int additional_len)
{
if (!testContext.isValid) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* This magic input tells us to set the reseed count to it's max count,
* so we can simulate PRNGTEST_Generate reaching max reseed count */
if ((entropy == NULL) && (entropy_len == 0) &&
(additional == NULL) && (additional_len == 0)) {
testContext.reseed_counter[0] = RESEED_VALUE;
return SECSuccess;
}
return prng_reseed(&testContext, entropy, entropy_len, additional,
additional_len);
}
SECStatus
PRNGTEST_Generate(PRUint8 *bytes, unsigned int bytes_len,
const PRUint8 *additional, unsigned int additional_len)
{
SECStatus rv;
if (!testContext.isValid) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* replicate reseed test from prng_GenerateGlobalRandomBytes */
if (testContext.reseed_counter[0] >= RESEED_VALUE) {
rv = prng_reseed(&testContext, NULL, 0, NULL, 0);
if (rv != SECSuccess) {
return rv;
}
}
return prng_generateNewBytes(&testContext, bytes, bytes_len,
additional, additional_len);
}
SECStatus
PRNGTEST_Uninstantiate()
{
if (!testContext.isValid) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
PORT_Memset(&testContext, 0, sizeof testContext);
return SECSuccess;
}
SECStatus
PRNGTEST_RunHealthTests()
{
static const PRUint8 entropy[] = {
0x8e, 0x9c, 0x0d, 0x25, 0x75, 0x22, 0x04, 0xf9,
0xc5, 0x79, 0x10, 0x8b, 0x23, 0x79, 0x37, 0x14,
0x9f, 0x2c, 0xc7, 0x0b, 0x39, 0xf8, 0xee, 0xef,
0x95, 0x0c, 0x97, 0x59, 0xfc, 0x0a, 0x85, 0x41,
0x76, 0x9d, 0x6d, 0x67, 0x00, 0x4e, 0x19, 0x12,
0x02, 0x16, 0x53, 0xea, 0xf2, 0x73, 0xd7, 0xd6,
0x7f, 0x7e, 0xc8, 0xae, 0x9c, 0x09, 0x99, 0x7d,
0xbb, 0x9e, 0x48, 0x7f, 0xbb, 0x96, 0x46, 0xb3,
0x03, 0x75, 0xf8, 0xc8, 0x69, 0x45, 0x3f, 0x97,
0x5e, 0x2e, 0x48, 0xe1, 0x5d, 0x58, 0x97, 0x4c
};
static const PRUint8 rng_known_result[] = {
0x16, 0xe1, 0x8c, 0x57, 0x21, 0xd8, 0xf1, 0x7e,
0x5a, 0xa0, 0x16, 0x0b, 0x7e, 0xa6, 0x25, 0xb4,
0x24, 0x19, 0xdb, 0x54, 0xfa, 0x35, 0x13, 0x66,
0xbb, 0xaa, 0x2a, 0x1b, 0x22, 0x33, 0x2e, 0x4a,
0x14, 0x07, 0x9d, 0x52, 0xfc, 0x73, 0x61, 0x48,
0xac, 0xc1, 0x22, 0xfc, 0xa4, 0xfc, 0xac, 0xa4,
0xdb, 0xda, 0x5b, 0x27, 0x33, 0xc4, 0xb3
};
static const PRUint8 reseed_entropy[] = {
0xc6, 0x0b, 0x0a, 0x30, 0x67, 0x07, 0xf4, 0xe2,
0x24, 0xa7, 0x51, 0x6f, 0x5f, 0x85, 0x3e, 0x5d,
0x67, 0x97, 0xb8, 0x3b, 0x30, 0x9c, 0x7a, 0xb1,
0x52, 0xc6, 0x1b, 0xc9, 0x46, 0xa8, 0x62, 0x79
};
static const PRUint8 additional_input[] = {
0x86, 0x82, 0x28, 0x98, 0xe7, 0xcb, 0x01, 0x14,
0xae, 0x87, 0x4b, 0x1d, 0x99, 0x1b, 0xc7, 0x41,
0x33, 0xff, 0x33, 0x66, 0x40, 0x95, 0x54, 0xc6,
0x67, 0x4d, 0x40, 0x2a, 0x1f, 0xf9, 0xeb, 0x65
};
static const PRUint8 rng_reseed_result[] = {
0x02, 0x0c, 0xc6, 0x17, 0x86, 0x49, 0xba, 0xc4,
0x7b, 0x71, 0x35, 0x05, 0xf0, 0xdb, 0x4a, 0xc2,
0x2c, 0x38, 0xc1, 0xa4, 0x42, 0xe5, 0x46, 0x4a,
0x7d, 0xf0, 0xbe, 0x47, 0x88, 0xb8, 0x0e, 0xc6,
0x25, 0x2b, 0x1d, 0x13, 0xef, 0xa6, 0x87, 0x96,
0xa3, 0x7d, 0x5b, 0x80, 0xc2, 0x38, 0x76, 0x61,
0xc7, 0x80, 0x5d, 0x0f, 0x05, 0x76, 0x85
};
static const PRUint8 rng_no_reseed_result[] = {
0xc4, 0x40, 0x41, 0x8c, 0xbf, 0x2f, 0x70, 0x23,
0x88, 0xf2, 0x7b, 0x30, 0xc3, 0xca, 0x1e, 0xf3,
0xef, 0x53, 0x81, 0x5d, 0x30, 0xed, 0x4c, 0xf1,
0xff, 0x89, 0xa5, 0xee, 0x92, 0xf8, 0xc0, 0x0f,
0x88, 0x53, 0xdf, 0xb6, 0x76, 0xf0, 0xaa, 0xd3,
0x2e, 0x1d, 0x64, 0x37, 0x3e, 0xe8, 0x4a, 0x02,
0xff, 0x0a, 0x7f, 0xe5, 0xe9, 0x2b, 0x6d
};
SECStatus rng_status = SECSuccess;
PR_STATIC_ASSERT(sizeof(rng_known_result) >= sizeof(rng_reseed_result));
PRUint8 result[sizeof(rng_known_result)];
/********************************************/
/* First test instantiate error path. */
/* In this case we supply enough entropy, */
/* but not enough seed. This will trigger */
/* the code that checks for a entropy */
/* source failure. */
/********************************************/
rng_status = PRNGTEST_Instantiate(entropy, 256 / PR_BITS_PER_BYTE,
NULL, 0, NULL, 0);
if (rng_status == SECSuccess) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (PORT_GetError() != SEC_ERROR_NEED_RANDOM) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* we failed with the proper error code, we can continue */
/********************************************/
/* Generate random bytes with a known seed. */
/********************************************/
rng_status = PRNGTEST_Instantiate(entropy, sizeof entropy,
NULL, 0, NULL, 0);
if (rng_status != SECSuccess) {
/* Error set by PRNGTEST_Instantiate */
return SECFailure;
}
rng_status = PRNGTEST_Generate(result, sizeof rng_known_result, NULL, 0);
if ((rng_status != SECSuccess) ||
(PORT_Memcmp(result, rng_known_result,
sizeof rng_known_result) != 0)) {
PRNGTEST_Uninstantiate();
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
rng_status = PRNGTEST_Reseed(reseed_entropy, sizeof reseed_entropy,
additional_input, sizeof additional_input);
if (rng_status != SECSuccess) {
/* Error set by PRNG_Reseed */
PRNGTEST_Uninstantiate();
return SECFailure;
}
rng_status = PRNGTEST_Generate(result, sizeof rng_reseed_result, NULL, 0);
if ((rng_status != SECSuccess) ||
(PORT_Memcmp(result, rng_reseed_result,
sizeof rng_reseed_result) != 0)) {
PRNGTEST_Uninstantiate();
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* This magic forces the reseed count to it's max count, so we can see if
* PRNGTEST_Generate will actually when it reaches it's count */
rng_status = PRNGTEST_Reseed(NULL, 0, NULL, 0);
if (rng_status != SECSuccess) {
PRNGTEST_Uninstantiate();
/* Error set by PRNG_Reseed */
return SECFailure;
}
/* This generate should now reseed */
rng_status = PRNGTEST_Generate(result, sizeof rng_reseed_result, NULL, 0);
if ((rng_status != SECSuccess) ||
/* NOTE we fail if the result is equal to the no_reseed_result.
* no_reseed_result is the value we would have gotten if we didn't
* do an automatic reseed in PRNGTEST_Generate */
(PORT_Memcmp(result, rng_no_reseed_result,
sizeof rng_no_reseed_result) == 0)) {
PRNGTEST_Uninstantiate();
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* make sure reseed fails when we don't supply enough entropy */
rng_status = PRNGTEST_Reseed(reseed_entropy, 4, NULL, 0);
if (rng_status == SECSuccess) {
PRNGTEST_Uninstantiate();
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (PORT_GetError() != SEC_ERROR_NEED_RANDOM) {
PRNGTEST_Uninstantiate();
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
rng_status = PRNGTEST_Uninstantiate();
if (rng_status != SECSuccess) {
/* Error set by PRNG_Uninstantiate */
return rng_status;
}
/* make sure uninstantiate fails if the contest is not initiated (also tests
* if the context was cleared in the previous Uninstantiate) */
rng_status = PRNGTEST_Uninstantiate();
if (rng_status == SECSuccess) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (PORT_GetError() != SEC_ERROR_LIBRARY_FAILURE) {
return rng_status;
}
return SECSuccess;
}