gecko/security/nss/lib/freebl/pqg.c
2009-04-07 03:36:45 +02:00

718 lines
24 KiB
C

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Netscape security libraries.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1994-2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* PQG parameter generation/verification. Based on FIPS 186-1.
*
* $Id: pqg.c,v 1.17 2009/03/26 23:16:37 glen.beasley%sun.com Exp $
*/
#ifdef FREEBL_NO_DEPEND
#include "stubs.h"
#endif
#include "prerr.h"
#include "secerr.h"
#include "prtypes.h"
#include "blapi.h"
#include "secitem.h"
#include "mpi.h"
#include "mpprime.h"
#include "mplogic.h"
#include "secmpi.h"
#define MAX_ITERATIONS 1000 /* Maximum number of iterations of primegen */
#define PQG_Q_PRIMALITY_TESTS 18 /* from HAC table 4.4 */
#define PQG_P_PRIMALITY_TESTS 5 /* from HAC table 4.4 */
/* XXX to be replaced by define in blapit.h */
#define BITS_IN_Q 160
/* For FIPS-compliance testing.
** The following array holds the seed defined in FIPS 186-1 appendix 5.
** This seed is used to generate P and Q according to appendix 2; use of
** this seed will exactly generate the PQG specified in appendix 2.
*/
#ifdef FIPS_186_1_A5_TEST
static const unsigned char fips_186_1_a5_pqseed[] = {
0xd5, 0x01, 0x4e, 0x4b, 0x60, 0xef, 0x2b, 0xa8,
0xb6, 0x21, 0x1b, 0x40, 0x62, 0xba, 0x32, 0x24,
0xe0, 0x42, 0x7d, 0xd3
};
#endif
/* Get a seed for generating P and Q. If in testing mode, copy in the
** seed from FIPS 186-1 appendix 5. Otherwise, obtain bytes from the
** global random number generator.
*/
static SECStatus
getPQseed(SECItem *seed, PRArenaPool* arena)
{
SECStatus rv;
if (!seed->data) {
seed->data = (unsigned char*)PORT_ArenaZAlloc(arena, seed->len);
}
if (!seed->data) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
return SECFailure;
}
#ifdef FIPS_186_1_A5_TEST
memcpy(seed->data, fips_186_1_a5_pqseed, seed->len);
return SECSuccess;
#else
rv = RNG_GenerateGlobalRandomBytes(seed->data, seed->len);
/*
* NIST CMVP disallows a sequence of 20 bytes with the most
* significant byte equal to 0. Perhaps they interpret
* "a sequence of at least 160 bits" as "a number >= 2^159".
* So we always set the most significant bit to 1. (bug 334533)
*/
seed->data[0] |= 0x80;
return rv;
#endif
}
/* Generate a candidate h value. If in testing mode, use the h value
** specified in FIPS 186-1 appendix 5, h = 2. Otherwise, obtain bytes
** from the global random number generator.
*/
static SECStatus
generate_h_candidate(SECItem *hit, mp_int *H)
{
SECStatus rv = SECSuccess;
mp_err err = MP_OKAY;
#ifdef FIPS_186_1_A5_TEST
memset(hit->data, 0, hit->len);
hit->data[hit->len-1] = 0x02;
#else
rv = RNG_GenerateGlobalRandomBytes(hit->data, hit->len);
#endif
if (rv)
return SECFailure;
err = mp_read_unsigned_octets(H, hit->data, hit->len);
if (err) {
MP_TO_SEC_ERROR(err);
return SECFailure;
}
return SECSuccess;
}
/* Compute SHA[(SEED + addend) mod 2**g]
** Result is placed in shaOutBuf.
** This computation is used in steps 2 and 7 of FIPS 186 Appendix 2.2 .
*/
static SECStatus
addToSeedThenSHA(const SECItem * seed,
unsigned long addend,
int g,
unsigned char * shaOutBuf)
{
SECItem str = { 0, 0, 0 };
mp_int s, sum, modulus, tmp;
mp_err err = MP_OKAY;
SECStatus rv = SECSuccess;
MP_DIGITS(&s) = 0;
MP_DIGITS(&sum) = 0;
MP_DIGITS(&modulus) = 0;
MP_DIGITS(&tmp) = 0;
CHECK_MPI_OK( mp_init(&s) );
CHECK_MPI_OK( mp_init(&sum) );
CHECK_MPI_OK( mp_init(&modulus) );
SECITEM_TO_MPINT(*seed, &s); /* s = seed */
/* seed += addend */
if (addend < MP_DIGIT_MAX) {
CHECK_MPI_OK( mp_add_d(&s, (mp_digit)addend, &s) );
} else {
CHECK_MPI_OK( mp_init(&tmp) );
CHECK_MPI_OK( mp_set_ulong(&tmp, addend) );
CHECK_MPI_OK( mp_add(&s, &tmp, &s) );
}
CHECK_MPI_OK( mp_div_2d(&s, (mp_digit)g, NULL, &sum) );/*sum = s mod 2**g */
MPINT_TO_SECITEM(&sum, &str, NULL);
rv = SHA1_HashBuf(shaOutBuf, str.data, str.len); /* SHA1 hash result */
cleanup:
mp_clear(&s);
mp_clear(&sum);
mp_clear(&modulus);
mp_clear(&tmp);
if (str.data)
SECITEM_ZfreeItem(&str, PR_FALSE);
if (err) {
MP_TO_SEC_ERROR(err);
return SECFailure;
}
return rv;
}
/*
** Perform steps 2 and 3 of FIPS 186, appendix 2.2.
** Generate Q from seed.
*/
static SECStatus
makeQfromSeed(
unsigned int g, /* input. Length of seed in bits. */
const SECItem * seed, /* input. */
mp_int * Q) /* output. */
{
unsigned char sha1[SHA1_LENGTH];
unsigned char sha2[SHA1_LENGTH];
unsigned char U[SHA1_LENGTH];
SECStatus rv = SECSuccess;
mp_err err = MP_OKAY;
int i;
/* ******************************************************************
** Step 2.
** "Compute U = SHA[SEED] XOR SHA[(SEED+1) mod 2**g]."
**/
CHECK_SEC_OK( SHA1_HashBuf(sha1, seed->data, seed->len) );
CHECK_SEC_OK( addToSeedThenSHA(seed, 1, g, sha2) );
for (i=0; i<SHA1_LENGTH; ++i)
U[i] = sha1[i] ^ sha2[i];
/* ******************************************************************
** Step 3.
** "Form Q from U by setting the most signficant bit (the 2**159 bit)
** and the least signficant bit to 1. In terms of boolean operations,
** Q = U OR 2**159 OR 1. Note that 2**159 < Q < 2**160."
*/
U[0] |= 0x80; /* U is MSB first */
U[SHA1_LENGTH-1] |= 0x01;
err = mp_read_unsigned_octets(Q, U, SHA1_LENGTH);
cleanup:
memset(U, 0, SHA1_LENGTH);
memset(sha1, 0, SHA1_LENGTH);
memset(sha2, 0, SHA1_LENGTH);
if (err) {
MP_TO_SEC_ERROR(err);
return SECFailure;
}
return rv;
}
/* Perform steps 7, 8 and 9 of FIPS 186, appendix 2.2.
** Generate P from Q, seed, L, and offset.
*/
static SECStatus
makePfromQandSeed(
unsigned int L, /* Length of P in bits. Per FIPS 186. */
unsigned int offset, /* Per FIPS 186, appendix 2.2. */
unsigned int g, /* input. Length of seed in bits. */
const SECItem * seed, /* input. */
const mp_int * Q, /* input. */
mp_int * P) /* output. */
{
unsigned int k; /* Per FIPS 186, appendix 2.2. */
unsigned int n; /* Per FIPS 186, appendix 2.2. */
mp_digit b; /* Per FIPS 186, appendix 2.2. */
unsigned char V_k[SHA1_LENGTH];
mp_int W, X, c, twoQ, V_n, tmp;
mp_err err = MP_OKAY;
SECStatus rv = SECSuccess;
/* Initialize bignums */
MP_DIGITS(&W) = 0;
MP_DIGITS(&X) = 0;
MP_DIGITS(&c) = 0;
MP_DIGITS(&twoQ) = 0;
MP_DIGITS(&V_n) = 0;
MP_DIGITS(&tmp) = 0;
CHECK_MPI_OK( mp_init(&W) );
CHECK_MPI_OK( mp_init(&X) );
CHECK_MPI_OK( mp_init(&c) );
CHECK_MPI_OK( mp_init(&twoQ) );
CHECK_MPI_OK( mp_init(&tmp) );
CHECK_MPI_OK( mp_init(&V_n) );
/* L - 1 = n*160 + b */
n = (L - 1) / BITS_IN_Q;
b = (L - 1) % BITS_IN_Q;
/* ******************************************************************
** Step 7.
** "for k = 0 ... n let
** V_k = SHA[(SEED + offset + k) mod 2**g]."
**
** Step 8.
** "Let W be the integer
** W = V_0 + (V_1 * 2**160) + ... + (V_n-1 * 2**((n-1)*160))
** + ((V_n mod 2**b) * 2**(n*160))
*/
for (k=0; k<n; ++k) { /* Do the first n terms of V_k */
/* Do step 7 for iteration k.
** V_k = SHA[(seed + offset + k) mod 2**g]
*/
CHECK_SEC_OK( addToSeedThenSHA(seed, offset + k, g, V_k) );
/* Do step 8 for iteration k.
** W += V_k * 2**(k*160)
*/
OCTETS_TO_MPINT(V_k, &tmp, SHA1_LENGTH); /* get bignum V_k */
CHECK_MPI_OK( mpl_lsh(&tmp, &tmp, k*160) ); /* tmp = V_k << k*160 */
CHECK_MPI_OK( mp_add(&W, &tmp, &W) ); /* W += tmp */
}
/* Step 8, continued.
** [W += ((V_n mod 2**b) * 2**(n*160))]
*/
CHECK_SEC_OK( addToSeedThenSHA(seed, offset + n, g, V_k) );
OCTETS_TO_MPINT(V_k, &V_n, SHA1_LENGTH); /* get bignum V_n */
CHECK_MPI_OK( mp_div_2d(&V_n, b, NULL, &tmp) ); /* tmp = V_n mod 2**b */
CHECK_MPI_OK( mpl_lsh(&tmp, &tmp, n*160) ); /* tmp = tmp << n*160 */
CHECK_MPI_OK( mp_add(&W, &tmp, &W) ); /* W += tmp */
/* Step 8, continued.
** "and let X = W + 2**(L-1).
** Note that 0 <= W < 2**(L-1) and hence 2**(L-1) <= X < 2**L."
*/
CHECK_MPI_OK( mpl_set_bit(&X, (mp_size)(L-1), 1) ); /* X = 2**(L-1) */
CHECK_MPI_OK( mp_add(&X, &W, &X) ); /* X += W */
/*************************************************************
** Step 9.
** "Let c = X mod 2q and set p = X - (c - 1).
** Note that p is congruent to 1 mod 2q."
*/
CHECK_MPI_OK( mp_mul_2(Q, &twoQ) ); /* 2q */
CHECK_MPI_OK( mp_mod(&X, &twoQ, &c) ); /* c = X mod 2q */
CHECK_MPI_OK( mp_sub_d(&c, 1, &c) ); /* c -= 1 */
CHECK_MPI_OK( mp_sub(&X, &c, P) ); /* P = X - c */
cleanup:
mp_clear(&W);
mp_clear(&X);
mp_clear(&c);
mp_clear(&twoQ);
mp_clear(&V_n);
mp_clear(&tmp);
if (err) {
MP_TO_SEC_ERROR(err);
return SECFailure;
}
return rv;
}
/*
** Generate G from h, P, and Q.
*/
static SECStatus
makeGfromH(const mp_int *P, /* input. */
const mp_int *Q, /* input. */
mp_int *H, /* input and output. */
mp_int *G, /* output. */
PRBool *passed)
{
mp_int exp, pm1;
mp_err err = MP_OKAY;
SECStatus rv = SECSuccess;
*passed = PR_FALSE;
MP_DIGITS(&exp) = 0;
MP_DIGITS(&pm1) = 0;
CHECK_MPI_OK( mp_init(&exp) );
CHECK_MPI_OK( mp_init(&pm1) );
CHECK_MPI_OK( mp_sub_d(P, 1, &pm1) ); /* P - 1 */
if ( mp_cmp(H, &pm1) >= 0) /* H >= P-1 */
CHECK_MPI_OK( mp_sub(H, &pm1, H) ); /* H = H mod (P-1) */
/* Let b = 2**n (smallest power of 2 greater than P).
** Since P-1 >= b/2, and H < b, quotient(H/(P-1)) = 0 or 1
** so the above operation safely computes H mod (P-1)
*/
/* Check for H = to 0 or 1. Regen H if so. (Regen means return error). */
if (mp_cmp_d(H, 1) <= 0) {
rv = SECFailure;
goto cleanup;
}
/* Compute G, according to the equation G = (H ** ((P-1)/Q)) mod P */
CHECK_MPI_OK( mp_div(&pm1, Q, &exp, NULL) ); /* exp = (P-1)/Q */
CHECK_MPI_OK( mp_exptmod(H, &exp, P, G) ); /* G = H ** exp mod P */
/* Check for G == 0 or G == 1, return error if so. */
if (mp_cmp_d(G, 1) <= 0) {
rv = SECFailure;
goto cleanup;
}
*passed = PR_TRUE;
cleanup:
mp_clear(&exp);
mp_clear(&pm1);
if (err) {
MP_TO_SEC_ERROR(err);
rv = SECFailure;
}
return rv;
}
SECStatus
PQG_ParamGen(unsigned int j, PQGParams **pParams, PQGVerify **pVfy)
{
unsigned int L; /* Length of P in bits. Per FIPS 186. */
unsigned int seedBytes;
if (j > 8 || !pParams || !pVfy) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
L = 512 + (j * 64); /* bits in P */
seedBytes = L/8;
return PQG_ParamGenSeedLen(j, seedBytes, pParams, pVfy);
}
/* This code uses labels and gotos, so that it can follow the numbered
** steps in the algorithms from FIPS 186 appendix 2.2 very closely,
** and so that the correctness of this code can be easily verified.
** So, please forgive the ugly c code.
**/
SECStatus
PQG_ParamGenSeedLen(unsigned int j, unsigned int seedBytes,
PQGParams **pParams, PQGVerify **pVfy)
{
unsigned int L; /* Length of P in bits. Per FIPS 186. */
unsigned int n; /* Per FIPS 186, appendix 2.2. */
unsigned int b; /* Per FIPS 186, appendix 2.2. */
unsigned int g; /* Per FIPS 186, appendix 2.2. */
unsigned int counter; /* Per FIPS 186, appendix 2.2. */
unsigned int offset; /* Per FIPS 186, appendix 2.2. */
SECItem *seed; /* Per FIPS 186, appendix 2.2. */
PRArenaPool *arena = NULL;
PQGParams *params = NULL;
PQGVerify *verify = NULL;
PRBool passed;
SECItem hit = { 0, 0, 0 };
mp_int P, Q, G, H, l;
mp_err err = MP_OKAY;
SECStatus rv = SECFailure;
int iterations = 0;
if (j > 8 || seedBytes < 20 || !pParams || !pVfy) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* Initialize an arena for the params. */
arena = PORT_NewArena(NSS_FREEBL_DEFAULT_CHUNKSIZE);
if (!arena) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
return SECFailure;
}
params = (PQGParams *)PORT_ArenaZAlloc(arena, sizeof(PQGParams));
if (!params) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
PORT_FreeArena(arena, PR_TRUE);
return SECFailure;
}
params->arena = arena;
/* Initialize an arena for the verify. */
arena = PORT_NewArena(NSS_FREEBL_DEFAULT_CHUNKSIZE);
if (!arena) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
PORT_FreeArena(params->arena, PR_TRUE);
return SECFailure;
}
verify = (PQGVerify *)PORT_ArenaZAlloc(arena, sizeof(PQGVerify));
if (!verify) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
PORT_FreeArena(arena, PR_TRUE);
PORT_FreeArena(params->arena, PR_TRUE);
return SECFailure;
}
verify->arena = arena;
seed = &verify->seed;
arena = NULL;
/* Initialize bignums */
MP_DIGITS(&P) = 0;
MP_DIGITS(&Q) = 0;
MP_DIGITS(&G) = 0;
MP_DIGITS(&H) = 0;
MP_DIGITS(&l) = 0;
CHECK_MPI_OK( mp_init(&P) );
CHECK_MPI_OK( mp_init(&Q) );
CHECK_MPI_OK( mp_init(&G) );
CHECK_MPI_OK( mp_init(&H) );
CHECK_MPI_OK( mp_init(&l) );
/* Compute lengths. */
L = 512 + (j * 64); /* bits in P */
n = (L - 1) / BITS_IN_Q; /* BITS_IN_Q is 160 */
b = (L - 1) % BITS_IN_Q;
g = seedBytes * BITS_PER_BYTE; /* bits in seed, NOT G of PQG. */
step_1:
/* ******************************************************************
** Step 1.
** "Choose an abitrary sequence of at least 160 bits and call it SEED.
** Let g be the length of SEED in bits."
*/
if (++iterations > MAX_ITERATIONS) { /* give up after a while */
PORT_SetError(SEC_ERROR_NEED_RANDOM);
goto cleanup;
}
seed->len = seedBytes;
CHECK_SEC_OK( getPQseed(seed, verify->arena) );
/* ******************************************************************
** Step 2.
** "Compute U = SHA[SEED] XOR SHA[(SEED+1) mod 2**g]."
**
** Step 3.
** "Form Q from U by setting the most signficant bit (the 2**159 bit)
** and the least signficant bit to 1. In terms of boolean operations,
** Q = U OR 2**159 OR 1. Note that 2**159 < Q < 2**160."
*/
CHECK_SEC_OK( makeQfromSeed(g, seed, &Q) );
/* ******************************************************************
** Step 4.
** "Use a robust primality testing algorithm to test whether q is prime."
**
** Appendix 2.1 states that a Rabin test with at least 50 iterations
** "will give an acceptable probability of error."
*/
/*CHECK_SEC_OK( prm_RabinTest(&Q, &passed) );*/
err = mpp_pprime(&Q, PQG_Q_PRIMALITY_TESTS);
passed = (err == MP_YES) ? SECSuccess : SECFailure;
/* ******************************************************************
** Step 5. "If q is not prime, goto step 1."
*/
if (passed != SECSuccess)
goto step_1;
/* ******************************************************************
** Step 6. "Let counter = 0 and offset = 2."
*/
counter = 0;
offset = 2;
step_7:
/* ******************************************************************
** Step 7.
** "for k = 0 ... n let
** V_k = SHA[(SEED + offset + k) mod 2**g]."
**
** Step 8.
** "Let W be the sum of (V_k * 2**(k*160)) for k = 0 ... n
** and let X = W + 2**(L-1).
** Note that 0 <= W < 2**(L-1) and hence 2**(L-1) <= X < 2**L."
**
** Step 9.
** "Let c = X mod 2q and set p = X - (c - 1).
** Note that p is congruent to 1 mod 2q."
*/
CHECK_SEC_OK( makePfromQandSeed(L, offset, g, seed, &Q, &P) );
/*************************************************************
** Step 10.
** "if p < 2**(L-1), then goto step 13."
*/
CHECK_MPI_OK( mpl_set_bit(&l, (mp_size)(L-1), 1) ); /* l = 2**(L-1) */
if (mp_cmp(&P, &l) < 0)
goto step_13;
/************************************************************
** Step 11.
** "Perform a robust primality test on p."
*/
/*CHECK_SEC_OK( prm_RabinTest(&P, &passed) );*/
err = mpp_pprime(&P, PQG_P_PRIMALITY_TESTS);
passed = (err == MP_YES) ? SECSuccess : SECFailure;
/* ******************************************************************
** Step 12. "If p passes the test performed in step 11, go to step 15."
*/
if (passed == SECSuccess)
goto step_15;
step_13:
/* ******************************************************************
** Step 13. "Let counter = counter + 1 and offset = offset + n + 1."
*/
counter++;
offset += n + 1;
/* ******************************************************************
** Step 14. "If counter >= 4096 goto step 1, otherwise go to step 7."
*/
if (counter >= 4096)
goto step_1;
goto step_7;
step_15:
/* ******************************************************************
** Step 15.
** "Save the value of SEED and the value of counter for use
** in certifying the proper generation of p and q."
*/
/* Generate h. */
SECITEM_AllocItem(NULL, &hit, L/8); /* h is no longer than p */
if (!hit.data) goto cleanup;
do {
/* loop generate h until 1<h<p-1 and (h**[(p-1)/q])mod p > 1 */
CHECK_SEC_OK( generate_h_candidate(&hit, &H) );
CHECK_SEC_OK( makeGfromH(&P, &Q, &H, &G, &passed) );
} while (passed != PR_TRUE);
/* All generation is done. Now, save the PQG params. */
MPINT_TO_SECITEM(&P, &params->prime, params->arena);
MPINT_TO_SECITEM(&Q, &params->subPrime, params->arena);
MPINT_TO_SECITEM(&G, &params->base, params->arena);
MPINT_TO_SECITEM(&H, &verify->h, verify->arena);
verify->counter = counter;
*pParams = params;
*pVfy = verify;
cleanup:
mp_clear(&P);
mp_clear(&Q);
mp_clear(&G);
mp_clear(&H);
mp_clear(&l);
if (err) {
MP_TO_SEC_ERROR(err);
rv = SECFailure;
}
if (rv) {
PORT_FreeArena(params->arena, PR_TRUE);
PORT_FreeArena(verify->arena, PR_TRUE);
}
if (hit.data) {
SECITEM_FreeItem(&hit, PR_FALSE);
}
return rv;
}
SECStatus
PQG_VerifyParams(const PQGParams *params,
const PQGVerify *vfy, SECStatus *result)
{
SECStatus rv = SECSuccess;
int passed;
unsigned int g, n, L, offset;
mp_int P, Q, G, P_, Q_, G_, r, h;
mp_err err = MP_OKAY;
int j;
#define CHECKPARAM(cond) \
if (!(cond)) { \
*result = SECFailure; \
goto cleanup; \
}
if (!params || !vfy || !result) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
MP_DIGITS(&P) = 0;
MP_DIGITS(&Q) = 0;
MP_DIGITS(&G) = 0;
MP_DIGITS(&P_) = 0;
MP_DIGITS(&Q_) = 0;
MP_DIGITS(&G_) = 0;
MP_DIGITS(&r) = 0;
MP_DIGITS(&h) = 0;
CHECK_MPI_OK( mp_init(&P) );
CHECK_MPI_OK( mp_init(&Q) );
CHECK_MPI_OK( mp_init(&G) );
CHECK_MPI_OK( mp_init(&P_) );
CHECK_MPI_OK( mp_init(&Q_) );
CHECK_MPI_OK( mp_init(&G_) );
CHECK_MPI_OK( mp_init(&r) );
CHECK_MPI_OK( mp_init(&h) );
*result = SECSuccess;
SECITEM_TO_MPINT(params->prime, &P);
SECITEM_TO_MPINT(params->subPrime, &Q);
SECITEM_TO_MPINT(params->base, &G);
/* 1. Q is 160 bits long. */
CHECKPARAM( mpl_significant_bits(&Q) == 160 );
/* 2. P is one of the 9 valid lengths. */
L = mpl_significant_bits(&P);
j = PQG_PBITS_TO_INDEX(L);
CHECKPARAM( j >= 0 && j <= 8 );
/* 3. G < P */
CHECKPARAM( mp_cmp(&G, &P) < 0 );
/* 4. P % Q == 1 */
CHECK_MPI_OK( mp_mod(&P, &Q, &r) );
CHECKPARAM( mp_cmp_d(&r, 1) == 0 );
/* 5. Q is prime */
CHECKPARAM( mpp_pprime(&Q, PQG_Q_PRIMALITY_TESTS) == MP_YES );
/* 6. P is prime */
CHECKPARAM( mpp_pprime(&P, PQG_P_PRIMALITY_TESTS) == MP_YES );
/* Steps 7-12 are done only if the optional PQGVerify is supplied. */
/* 7. counter < 4096 */
CHECKPARAM( vfy->counter < 4096 );
/* 8. g >= 160 and g < 2048 (g is length of seed in bits) */
g = vfy->seed.len * 8;
CHECKPARAM( g >= 160 && g < 2048 );
/* 9. Q generated from SEED matches Q in PQGParams. */
CHECK_SEC_OK( makeQfromSeed(g, &vfy->seed, &Q_) );
CHECKPARAM( mp_cmp(&Q, &Q_) == 0 );
/* 10. P generated from (L, counter, g, SEED, Q) matches P in PQGParams. */
n = (L - 1) / BITS_IN_Q;
offset = vfy->counter * (n + 1) + 2;
CHECK_SEC_OK( makePfromQandSeed(L, offset, g, &vfy->seed, &Q, &P_) );
CHECKPARAM( mp_cmp(&P, &P_) == 0 );
/* Next two are optional: if h == 0 ignore */
if (vfy->h.len == 0) goto cleanup;
/* 11. 1 < h < P-1 */
SECITEM_TO_MPINT(vfy->h, &h);
CHECK_MPI_OK( mpl_set_bit(&P, 0, 0) ); /* P is prime, p-1 == zero 1st bit */
CHECKPARAM( mp_cmp_d(&h, 1) > 0 && mp_cmp(&h, &P) );
CHECK_MPI_OK( mpl_set_bit(&P, 0, 1) ); /* set it back */
/* 12. G generated from h matches G in PQGParams. */
CHECK_SEC_OK( makeGfromH(&P, &Q, &h, &G_, &passed) );
CHECKPARAM( passed && mp_cmp(&G, &G_) == 0 );
cleanup:
mp_clear(&P);
mp_clear(&Q);
mp_clear(&G);
mp_clear(&P_);
mp_clear(&Q_);
mp_clear(&G_);
mp_clear(&r);
mp_clear(&h);
if (err) {
MP_TO_SEC_ERROR(err);
rv = SECFailure;
}
return rv;
}
/**************************************************************************
* Free the PQGParams struct and the things it points to. *
**************************************************************************/
void
PQG_DestroyParams(PQGParams *params)
{
if (params == NULL)
return;
if (params->arena != NULL) {
PORT_FreeArena(params->arena, PR_FALSE); /* don't zero it */
} else {
SECITEM_FreeItem(&params->prime, PR_FALSE); /* don't free prime */
SECITEM_FreeItem(&params->subPrime, PR_FALSE); /* don't free subPrime */
SECITEM_FreeItem(&params->base, PR_FALSE); /* don't free base */
PORT_Free(params);
}
}
/**************************************************************************
* Free the PQGVerify struct and the things it points to. *
**************************************************************************/
void
PQG_DestroyVerify(PQGVerify *vfy)
{
if (vfy == NULL)
return;
if (vfy->arena != NULL) {
PORT_FreeArena(vfy->arena, PR_FALSE); /* don't zero it */
} else {
SECITEM_FreeItem(&vfy->seed, PR_FALSE); /* don't free seed */
SECITEM_FreeItem(&vfy->h, PR_FALSE); /* don't free h */
PORT_Free(vfy);
}
}