diff options
Diffstat (limited to 'security/nss/lib/freebl/drbg.c')
| -rw-r--r-- | security/nss/lib/freebl/drbg.c | 1024 |
1 files changed, 1024 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/drbg.c b/security/nss/lib/freebl/drbg.c new file mode 100644 index 0000000000..3ed1751c3e --- /dev/null +++ b/security/nss/lib/freebl/drbg.c @@ -0,0 +1,1024 @@ +/* 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 \ + */ +#define PRNG_ENTROPY_BLOCK_SIZE SHA256_LENGTH + +/* 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 */ + /* 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 */ + /* for continuous entropy check */ + PRUint8 previousEntropyHash[SHA256_LENGTH]; +}; + +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; + } + SHA256_DestroyContext(&ctx, PR_FALSE); + 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; +} + +static PRCallOnceType coRNGInitEntropy; + +static PRStatus +prng_initEntropy(void) +{ + size_t length; + PRUint8 block[PRNG_ENTROPY_BLOCK_SIZE]; + SHA256Context ctx; + + /* For FIPS 140-2 4.9.2 continuous random number generator test, + * fetch the initial entropy from the system RNG and keep it for + * later comparison. */ + length = RNG_SystemRNG(block, sizeof(block)); + if (length == 0) { + return PR_FAILURE; /* error is already set */ + } + PORT_Assert(length == sizeof(block)); + + /* Store the hash of the entropy block rather than the block + * itself for backward secrecy. */ + SHA256_Begin(&ctx); + SHA256_Update(&ctx, block, sizeof(block)); + SHA256_End(&ctx, globalrng->previousEntropyHash, NULL, + sizeof(globalrng->previousEntropyHash)); + PORT_Memset(block, 0, sizeof(block)); + SHA256_DestroyContext(&ctx, PR_FALSE); + return PR_SUCCESS; +} + +static SECStatus +prng_getEntropy(PRUint8 *buffer, size_t requestLength) +{ + size_t total = 0; + PRUint8 block[PRNG_ENTROPY_BLOCK_SIZE]; + PRUint8 hash[SHA256_LENGTH]; + SHA256Context ctx; + SECStatus rv = SECSuccess; + + if (PR_CallOnce(&coRNGInitEntropy, prng_initEntropy) != PR_SUCCESS) { + PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); + return SECFailure; + } + + /* For FIPS 140-2 4.9.2 continuous random generator test, + * iteratively fetch fixed sized blocks from the system and + * compare consecutive blocks. */ + while (total < requestLength) { + size_t length = RNG_SystemRNG(block, sizeof(block)); + if (length == 0) { + rv = SECFailure; /* error is already set */ + goto out; + } + PORT_Assert(length == sizeof(block)); + + /* Store the hash of the entropy block rather than the block + * itself for backward secrecy. */ + SHA256_Begin(&ctx); + SHA256_Update(&ctx, block, sizeof(block)); + SHA256_End(&ctx, hash, NULL, sizeof(hash)); + + if (PORT_Memcmp(globalrng->previousEntropyHash, hash, sizeof(hash)) == 0) { + PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); + rv = SECFailure; + goto out; + } + PORT_Memcpy(globalrng->previousEntropyHash, hash, sizeof(hash)); + length = PR_MIN(requestLength - total, sizeof(block)); + PORT_Memcpy(buffer, block, length); + total += length; + buffer += length; + } + +out: + PORT_Memset(hash, 0, sizeof hash); + PORT_Memset(block, 0, sizeof block); + return rv; +} + +/* + * 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]; + SECStatus rv; + + /* if entropy wasn't supplied, fetch it. (normal operation case) */ + if (entropy == NULL) { + entropy_len = PRNG_SEEDLEN; + rv = prng_getEntropy(&noiseData[sizeof rng->V_Data], entropy_len); + if (rv != SECSuccess) { + return SECFailure; /* error is already set */ + } + } 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]; + + 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 (no_of_returned_bytes < SHA256_LENGTH) { + len = no_of_returned_bytes; + } + PORT_Memcpy(returned_bytes, thisHash, len); + 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); + SHA256_DestroyContext(&ctx, PR_FALSE); + } + 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); + SHA256_DestroyContext(&ctx, PR_FALSE); +#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)); + } 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 */ + PORT_Memset(H, 0, sizeof H); + 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 */ + 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 */ + rv = prng_getEntropy(bytes, sizeof bytes); + if (rv == SECSuccess) { + /* 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, sizeof bytes); + } else { + rv = prng_reseed_test(globalrng, bytes, sizeof bytes, NULL, 0); + } + memset(bytes, 0, sizeof bytes); + } 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; +} |