diff options
Diffstat (limited to 'security/nss/lib/freebl/rsa.c')
| -rw-r--r-- | security/nss/lib/freebl/rsa.c | 1725 |
1 files changed, 1725 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/rsa.c b/security/nss/lib/freebl/rsa.c new file mode 100644 index 0000000000..67d65ba2b4 --- /dev/null +++ b/security/nss/lib/freebl/rsa.c @@ -0,0 +1,1725 @@ +/* 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/. */ + +/* + * RSA key generation, public key op, private key op. + */ +#ifdef FREEBL_NO_DEPEND +#include "stubs.h" +#endif + +#include "secerr.h" + +#include "prclist.h" +#include "nssilock.h" +#include "prinit.h" +#include "blapi.h" +#include "mpi.h" +#include "mpprime.h" +#include "mplogic.h" +#include "secmpi.h" +#include "secitem.h" +#include "blapii.h" + +/* The minimal required randomness is 64 bits */ +/* EXP_BLINDING_RANDOMNESS_LEN is the length of the randomness in mp_digits */ +/* for 32 bits platforts it is 2 mp_digits (= 2 * 32 bits), for 64 bits it is equal to 128 bits */ +#define EXP_BLINDING_RANDOMNESS_LEN ((128 + MP_DIGIT_BIT - 1) / MP_DIGIT_BIT) +#define EXP_BLINDING_RANDOMNESS_LEN_BYTES (EXP_BLINDING_RANDOMNESS_LEN * sizeof(mp_digit)) + +/* +** Number of times to attempt to generate a prime (p or q) from a random +** seed (the seed changes for each iteration). +*/ +#define MAX_PRIME_GEN_ATTEMPTS 10 +/* +** Number of times to attempt to generate a key. The primes p and q change +** for each attempt. +*/ +#define MAX_KEY_GEN_ATTEMPTS 10 + +/* Blinding Parameters max cache size */ +#define RSA_BLINDING_PARAMS_MAX_CACHE_SIZE 20 + +/* exponent should not be greater than modulus */ +#define BAD_RSA_KEY_SIZE(modLen, expLen) \ + ((expLen) > (modLen) || (modLen) > RSA_MAX_MODULUS_BITS / 8 || \ + (expLen) > RSA_MAX_EXPONENT_BITS / 8) + +struct blindingParamsStr; +typedef struct blindingParamsStr blindingParams; + +struct blindingParamsStr { + blindingParams *next; + mp_int f, g; /* blinding parameter */ + int counter; /* number of remaining uses of (f, g) */ +}; + +/* +** RSABlindingParamsStr +** +** For discussion of Paul Kocher's timing attack against an RSA private key +** operation, see http://www.cryptography.com/timingattack/paper.html. The +** countermeasure to this attack, known as blinding, is also discussed in +** the Handbook of Applied Cryptography, 11.118-11.119. +*/ +struct RSABlindingParamsStr { + /* Blinding-specific parameters */ + PRCList link; /* link to list of structs */ + SECItem modulus; /* list element "key" */ + blindingParams *free, *bp; /* Blinding parameters queue */ + blindingParams array[RSA_BLINDING_PARAMS_MAX_CACHE_SIZE]; + /* precalculate montegomery reduction value */ + mp_digit n0i; /* n0i = -( n & MP_DIGIT) ** -1 mod mp_RADIX */ +}; +typedef struct RSABlindingParamsStr RSABlindingParams; + +/* +** RSABlindingParamsListStr +** +** List of key-specific blinding params. The arena holds the volatile pool +** of memory for each entry and the list itself. The lock is for list +** operations, in this case insertions and iterations, as well as control +** of the counter for each set of blinding parameters. +*/ +struct RSABlindingParamsListStr { + PZLock *lock; /* Lock for the list */ + PRCondVar *cVar; /* Condidtion Variable */ + int waitCount; /* Number of threads waiting on cVar */ + PRCList head; /* Pointer to the list */ +}; + +/* +** The master blinding params list. +*/ +static struct RSABlindingParamsListStr blindingParamsList = { 0 }; + +/* Number of times to reuse (f, g). Suggested by Paul Kocher */ +#define RSA_BLINDING_PARAMS_MAX_REUSE 50 + +/* Global, allows optional use of blinding. On by default. */ +/* Cannot be changed at the moment, due to thread-safety issues. */ +static PRBool nssRSAUseBlinding = PR_TRUE; + +static SECStatus +rsa_build_from_primes(const mp_int *p, const mp_int *q, + mp_int *e, PRBool needPublicExponent, + mp_int *d, PRBool needPrivateExponent, + RSAPrivateKey *key, unsigned int keySizeInBits) +{ + mp_int n, phi; + mp_int psub1, qsub1, tmp; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + MP_DIGITS(&n) = 0; + MP_DIGITS(&phi) = 0; + MP_DIGITS(&psub1) = 0; + MP_DIGITS(&qsub1) = 0; + MP_DIGITS(&tmp) = 0; + CHECK_MPI_OK(mp_init(&n)); + CHECK_MPI_OK(mp_init(&phi)); + CHECK_MPI_OK(mp_init(&psub1)); + CHECK_MPI_OK(mp_init(&qsub1)); + CHECK_MPI_OK(mp_init(&tmp)); + /* p and q must be distinct. */ + if (mp_cmp(p, q) == 0) { + PORT_SetError(SEC_ERROR_NEED_RANDOM); + rv = SECFailure; + goto cleanup; + } + /* 1. Compute n = p*q */ + CHECK_MPI_OK(mp_mul(p, q, &n)); + /* verify that the modulus has the desired number of bits */ + if ((unsigned)mpl_significant_bits(&n) != keySizeInBits) { + PORT_SetError(SEC_ERROR_NEED_RANDOM); + rv = SECFailure; + goto cleanup; + } + + /* at least one exponent must be given */ + PORT_Assert(!(needPublicExponent && needPrivateExponent)); + + /* 2. Compute phi = (p-1)*(q-1) */ + CHECK_MPI_OK(mp_sub_d(p, 1, &psub1)); + CHECK_MPI_OK(mp_sub_d(q, 1, &qsub1)); + if (needPublicExponent || needPrivateExponent) { + CHECK_MPI_OK(mp_lcm(&psub1, &qsub1, &phi)); + /* 3. Compute d = e**-1 mod(phi) */ + /* or e = d**-1 mod(phi) as necessary */ + if (needPublicExponent) { + err = mp_invmod(d, &phi, e); + } else { + err = mp_invmod(e, &phi, d); + } + } else { + err = MP_OKAY; + } + /* Verify that phi(n) and e have no common divisors */ + if (err != MP_OKAY) { + if (err == MP_UNDEF) { + PORT_SetError(SEC_ERROR_NEED_RANDOM); + err = MP_OKAY; /* to keep PORT_SetError from being called again */ + rv = SECFailure; + } + goto cleanup; + } + + /* 4. Compute exponent1 = d mod (p-1) */ + CHECK_MPI_OK(mp_mod(d, &psub1, &tmp)); + MPINT_TO_SECITEM(&tmp, &key->exponent1, key->arena); + /* 5. Compute exponent2 = d mod (q-1) */ + CHECK_MPI_OK(mp_mod(d, &qsub1, &tmp)); + MPINT_TO_SECITEM(&tmp, &key->exponent2, key->arena); + /* 6. Compute coefficient = q**-1 mod p */ + CHECK_MPI_OK(mp_invmod(q, p, &tmp)); + MPINT_TO_SECITEM(&tmp, &key->coefficient, key->arena); + + /* copy our calculated results, overwrite what is there */ + key->modulus.data = NULL; + MPINT_TO_SECITEM(&n, &key->modulus, key->arena); + key->privateExponent.data = NULL; + MPINT_TO_SECITEM(d, &key->privateExponent, key->arena); + key->publicExponent.data = NULL; + MPINT_TO_SECITEM(e, &key->publicExponent, key->arena); + key->prime1.data = NULL; + MPINT_TO_SECITEM(p, &key->prime1, key->arena); + key->prime2.data = NULL; + MPINT_TO_SECITEM(q, &key->prime2, key->arena); +cleanup: + mp_clear(&n); + mp_clear(&phi); + mp_clear(&psub1); + mp_clear(&qsub1); + mp_clear(&tmp); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +SECStatus +generate_prime(mp_int *prime, int primeLen) +{ + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + int piter; + unsigned char *pb = NULL; + pb = PORT_Alloc(primeLen); + if (!pb) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + goto cleanup; + } + for (piter = 0; piter < MAX_PRIME_GEN_ATTEMPTS; piter++) { + CHECK_SEC_OK(RNG_GenerateGlobalRandomBytes(pb, primeLen)); + pb[0] |= 0xC0; /* set two high-order bits */ + pb[primeLen - 1] |= 0x01; /* set low-order bit */ + CHECK_MPI_OK(mp_read_unsigned_octets(prime, pb, primeLen)); + err = mpp_make_prime_secure(prime, primeLen * 8, PR_FALSE); + if (err != MP_NO) + goto cleanup; + /* keep going while err == MP_NO */ + } +cleanup: + if (pb) + PORT_ZFree(pb, primeLen); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +/* + * make sure the key components meet fips186 requirements. + */ +static PRBool +rsa_fips186_verify(mp_int *p, mp_int *q, mp_int *d, int keySizeInBits) +{ + mp_int pq_diff; + mp_err err = MP_OKAY; + PRBool ret = PR_FALSE; + + if (keySizeInBits < 250) { + /* not a valid FIPS length, no point in our other tests */ + /* if you are here, and in FIPS mode, you are outside the security + * policy */ + return PR_TRUE; + } + + /* p & q are already known to be greater then sqrt(2)*2^(keySize/2-1) */ + /* we also know that gcd(p-1,e) = 1 and gcd(q-1,e) = 1 because the + * mp_invmod() function will fail. */ + /* now check p-q > 2^(keysize/2-100) */ + MP_DIGITS(&pq_diff) = 0; + CHECK_MPI_OK(mp_init(&pq_diff)); + /* NSS always has p > q, so we know pq_diff is positive */ + CHECK_MPI_OK(mp_sub(p, q, &pq_diff)); + if ((unsigned)mpl_significant_bits(&pq_diff) < (keySizeInBits / 2 - 100)) { + goto cleanup; + } + /* now verify d is large enough*/ + if ((unsigned)mpl_significant_bits(d) < (keySizeInBits / 2)) { + goto cleanup; + } + ret = PR_TRUE; + +cleanup: + mp_clear(&pq_diff); + return ret; +} + +/* +** Generate and return a new RSA public and private key. +** Both keys are encoded in a single RSAPrivateKey structure. +** "cx" is the random number generator context +** "keySizeInBits" is the size of the key to be generated, in bits. +** 512, 1024, etc. +** "publicExponent" when not NULL is a pointer to some data that +** represents the public exponent to use. The data is a byte +** encoded integer, in "big endian" order. +*/ +RSAPrivateKey * +RSA_NewKey(int keySizeInBits, SECItem *publicExponent) +{ + unsigned int primeLen; + mp_int p = { 0, 0, 0, NULL }; + mp_int q = { 0, 0, 0, NULL }; + mp_int e = { 0, 0, 0, NULL }; + mp_int d = { 0, 0, 0, NULL }; + int kiter; + int max_attempts; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + int prerr = 0; + RSAPrivateKey *key = NULL; + PLArenaPool *arena = NULL; + /* Require key size to be a multiple of 16 bits. */ + if (!publicExponent || keySizeInBits % 16 != 0 || + BAD_RSA_KEY_SIZE((unsigned int)keySizeInBits / 8, publicExponent->len)) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return NULL; + } + /* 1. Set the public exponent and check if it's uneven and greater than 2.*/ + MP_DIGITS(&e) = 0; + CHECK_MPI_OK(mp_init(&e)); + SECITEM_TO_MPINT(*publicExponent, &e); + if (mp_iseven(&e) || !(mp_cmp_d(&e, 2) > 0)) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + goto cleanup; + } +#ifndef NSS_FIPS_DISABLED + /* Check that the exponent is not smaller than 65537 */ + if (mp_cmp_d(&e, 0x10001) < 0) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + goto cleanup; + } +#endif + + /* 2. Allocate arena & key */ + arena = PORT_NewArena(NSS_FREEBL_DEFAULT_CHUNKSIZE); + if (!arena) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + goto cleanup; + } + key = PORT_ArenaZNew(arena, RSAPrivateKey); + if (!key) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + goto cleanup; + } + key->arena = arena; + /* length of primes p and q (in bytes) */ + primeLen = keySizeInBits / (2 * PR_BITS_PER_BYTE); + MP_DIGITS(&p) = 0; + MP_DIGITS(&q) = 0; + MP_DIGITS(&d) = 0; + CHECK_MPI_OK(mp_init(&p)); + CHECK_MPI_OK(mp_init(&q)); + CHECK_MPI_OK(mp_init(&d)); + /* 3. Set the version number (PKCS1 v1.5 says it should be zero) */ + SECITEM_AllocItem(arena, &key->version, 1); + key->version.data[0] = 0; + + kiter = 0; + max_attempts = 5 * (keySizeInBits / 2); /* FIPS 186-4 B.3.3 steps 4.7 and 5.8 */ + do { + PORT_SetError(0); + CHECK_SEC_OK(generate_prime(&p, primeLen)); + CHECK_SEC_OK(generate_prime(&q, primeLen)); + /* Assure p > q */ + /* NOTE: PKCS #1 does not require p > q, and NSS doesn't use any + * implementation optimization that requires p > q. We can remove + * this code in the future. + */ + if (mp_cmp(&p, &q) < 0) + mp_exch(&p, &q); + /* Attempt to use these primes to generate a key */ + rv = rsa_build_from_primes(&p, &q, + &e, PR_FALSE, /* needPublicExponent=false */ + &d, PR_TRUE, /* needPrivateExponent=true */ + key, keySizeInBits); + if (rv == SECSuccess) { + if (rsa_fips186_verify(&p, &q, &d, keySizeInBits)) { + break; + } + prerr = SEC_ERROR_NEED_RANDOM; /* retry with different values */ + } else { + prerr = PORT_GetError(); + } + kiter++; + /* loop until have primes */ + } while (prerr == SEC_ERROR_NEED_RANDOM && kiter < max_attempts); + +cleanup: + mp_clear(&p); + mp_clear(&q); + mp_clear(&e); + mp_clear(&d); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + if (rv && arena) { + PORT_FreeArena(arena, PR_TRUE); + key = NULL; + } + return key; +} + +mp_err +rsa_is_prime(mp_int *p) +{ + int res; + + /* run a Fermat test */ + res = mpp_fermat(p, 2); + if (res != MP_OKAY) { + return res; + } + + /* If that passed, run some Miller-Rabin tests */ + res = mpp_pprime_secure(p, 2); + return res; +} + +/* + * Factorize a RSA modulus n into p and q by using the exponents e and d. + * + * In: e, d, n + * Out: p, q + * + * See Handbook of Applied Cryptography, 8.2.2(i). + * + * The algorithm is probabilistic, it is run 64 times and each run has a 50% + * chance of succeeding with a runtime of O(log(e*d)). + * + * The returned p might be smaller than q. + */ +static mp_err +rsa_factorize_n_from_exponents(mp_int *e, mp_int *d, mp_int *p, mp_int *q, + mp_int *n) +{ + /* lambda is the private modulus: e*d = 1 mod lambda */ + /* so: e*d - 1 = k*lambda = t*2^s where t is odd */ + mp_int klambda; + mp_int t, onetwentyeight; + unsigned long s = 0; + unsigned long i; + + /* cand = a^(t * 2^i) mod n, next_cand = a^(t * 2^(i+1)) mod n */ + mp_int a; + mp_int cand; + mp_int next_cand; + + mp_int n_minus_one; + mp_err err = MP_OKAY; + + MP_DIGITS(&klambda) = 0; + MP_DIGITS(&t) = 0; + MP_DIGITS(&a) = 0; + MP_DIGITS(&cand) = 0; + MP_DIGITS(&n_minus_one) = 0; + MP_DIGITS(&next_cand) = 0; + MP_DIGITS(&onetwentyeight) = 0; + CHECK_MPI_OK(mp_init(&klambda)); + CHECK_MPI_OK(mp_init(&t)); + CHECK_MPI_OK(mp_init(&a)); + CHECK_MPI_OK(mp_init(&cand)); + CHECK_MPI_OK(mp_init(&n_minus_one)); + CHECK_MPI_OK(mp_init(&next_cand)); + CHECK_MPI_OK(mp_init(&onetwentyeight)); + + mp_set_int(&onetwentyeight, 128); + + /* calculate k*lambda = e*d - 1 */ + CHECK_MPI_OK(mp_mul(e, d, &klambda)); + CHECK_MPI_OK(mp_sub_d(&klambda, 1, &klambda)); + + /* factorize klambda into t*2^s */ + CHECK_MPI_OK(mp_copy(&klambda, &t)); + while (mpp_divis_d(&t, 2) == MP_YES) { + CHECK_MPI_OK(mp_div_2(&t, &t)); + s += 1; + } + + /* precompute n_minus_one = n - 1 */ + CHECK_MPI_OK(mp_copy(n, &n_minus_one)); + CHECK_MPI_OK(mp_sub_d(&n_minus_one, 1, &n_minus_one)); + + /* pick random bases a, each one has a 50% leading to a factorization */ + CHECK_MPI_OK(mp_set_int(&a, 2)); + /* The following is equivalent to for (a=2, a <= 128, a+=2) */ + while (mp_cmp(&a, &onetwentyeight) <= 0) { + /* compute the base cand = a^(t * 2^0) [i = 0] */ + CHECK_MPI_OK(mp_exptmod(&a, &t, n, &cand)); + + for (i = 0; i < s; i++) { + /* condition 1: skip the base if we hit a trivial factor of n */ + if (mp_cmp(&cand, &n_minus_one) == 0 || mp_cmp_d(&cand, 1) == 0) { + break; + } + + /* increase i in a^(t * 2^i) by squaring the number */ + CHECK_MPI_OK(mp_exptmod_d(&cand, 2, n, &next_cand)); + + /* condition 2: a^(t * 2^(i+1)) = 1 mod n */ + if (mp_cmp_d(&next_cand, 1) == 0) { + /* conditions verified, gcd(a^(t * 2^i) - 1, n) is a factor */ + CHECK_MPI_OK(mp_sub_d(&cand, 1, &cand)); + CHECK_MPI_OK(mp_gcd(&cand, n, p)); + if (mp_cmp_d(p, 1) == 0) { + CHECK_MPI_OK(mp_add_d(&cand, 1, &cand)); + break; + } + CHECK_MPI_OK(mp_div(n, p, q, NULL)); + goto cleanup; + } + CHECK_MPI_OK(mp_copy(&next_cand, &cand)); + } + + CHECK_MPI_OK(mp_add_d(&a, 2, &a)); + } + + /* if we reach here it's likely (2^64 - 1 / 2^64) that d is wrong */ + err = MP_RANGE; + +cleanup: + mp_clear(&klambda); + mp_clear(&t); + mp_clear(&a); + mp_clear(&cand); + mp_clear(&n_minus_one); + mp_clear(&next_cand); + mp_clear(&onetwentyeight); + return err; +} + +/* + * Try to find the two primes based on 2 exponents plus a prime. + * + * In: e, d and p. + * Out: p,q. + * + * Step 1, Since d = e**-1 mod phi, we know that d*e == 1 mod phi, or + * d*e = 1+k*phi, or d*e-1 = k*phi. since d is less than phi and e is + * usually less than d, then k must be an integer between e-1 and 1 + * (probably on the order of e). + * Step 1a, We can divide k*phi by prime-1 and get k*(q-1). This will reduce + * the size of our division through the rest of the loop. + * Step 2, Loop through the values k=e-1 to 1 looking for k. k should be on + * the order or e, and e is typically small. This may take a while for + * a large random e. We are looking for a k that divides kphi + * evenly. Once we find a k that divides kphi evenly, we assume it + * is the true k. It's possible this k is not the 'true' k but has + * swapped factors of p-1 and/or q-1. Because of this, we + * tentatively continue Steps 3-6 inside this loop, and may return looking + * for another k on failure. + * Step 3, Calculate our tentative phi=kphi/k. Note: real phi is (p-1)*(q-1). + * Step 4a, kphi is k*(q-1), so phi is our tenative q-1. q = phi+1. + * If k is correct, q should be the right length and prime. + * Step 4b, It's possible q-1 and k could have swapped factors. We now have a + * possible solution that meets our criteria. It may not be the only + * solution, however, so we keep looking. If we find more than one, + * we will fail since we cannot determine which is the correct + * solution, and returning the wrong modulus will compromise both + * moduli. If no other solution is found, we return the unique solution. + * + * This will return p & q. q may be larger than p in the case that p was given + * and it was the smaller prime. + */ +static mp_err +rsa_get_prime_from_exponents(mp_int *e, mp_int *d, mp_int *p, mp_int *q, + mp_int *n, unsigned int keySizeInBits) +{ + mp_int kphi; /* k*phi */ + mp_int k; /* current guess at 'k' */ + mp_int phi; /* (p-1)(q-1) */ + mp_int r; /* remainder */ + mp_int tmp; /* p-1 if p is given */ + mp_err err = MP_OKAY; + unsigned int order_k; + + MP_DIGITS(&kphi) = 0; + MP_DIGITS(&phi) = 0; + MP_DIGITS(&k) = 0; + MP_DIGITS(&r) = 0; + MP_DIGITS(&tmp) = 0; + CHECK_MPI_OK(mp_init(&kphi)); + CHECK_MPI_OK(mp_init(&phi)); + CHECK_MPI_OK(mp_init(&k)); + CHECK_MPI_OK(mp_init(&r)); + CHECK_MPI_OK(mp_init(&tmp)); + + /* our algorithm looks for a factor k whose maximum size is dependent + * on the size of our smallest exponent, which had better be the public + * exponent (if it's the private, the key is vulnerable to a brute force + * attack). + * + * since our factor search is linear, we need to limit the maximum + * size of the public key. this should not be a problem normally, since + * public keys are usually small. + * + * if we want to handle larger public key sizes, we should have + * a version which tries to 'completely' factor k*phi (where completely + * means 'factor into primes, or composites with which are products of + * large primes). Once we have all the factors, we can sort them out and + * try different combinations to form our phi. The risk is if (p-1)/2, + * (q-1)/2, and k are all large primes. In any case if the public key + * is small (order of 20 some bits), then a linear search for k is + * manageable. + */ + if (mpl_significant_bits(e) > 23) { + err = MP_RANGE; + goto cleanup; + } + + /* calculate k*phi = e*d - 1 */ + CHECK_MPI_OK(mp_mul(e, d, &kphi)); + CHECK_MPI_OK(mp_sub_d(&kphi, 1, &kphi)); + + /* kphi is (e*d)-1, which is the same as k*(p-1)(q-1) + * d < (p-1)(q-1), therefor k must be less than e-1 + * We can narrow down k even more, though. Since p and q are odd and both + * have their high bit set, then we know that phi must be on order of + * keySizeBits. + */ + order_k = (unsigned)mpl_significant_bits(&kphi) - keySizeInBits; + + if (order_k <= 1) { + err = MP_RANGE; + goto cleanup; + } + + /* for (k=kinit; order(k) >= order_k; k--) { */ + /* k=kinit: k can't be bigger than kphi/2^(keySizeInBits -1) */ + CHECK_MPI_OK(mp_2expt(&k, keySizeInBits - 1)); + CHECK_MPI_OK(mp_div(&kphi, &k, &k, NULL)); + if (mp_cmp(&k, e) >= 0) { + /* also can't be bigger then e-1 */ + CHECK_MPI_OK(mp_sub_d(e, 1, &k)); + } + + /* calculate our temp value */ + /* This saves recalculating this value when the k guess is wrong, which + * is reasonably frequent. */ + /* tmp = p-1 (used to calculate q-1= phi/tmp) */ + CHECK_MPI_OK(mp_sub_d(p, 1, &tmp)); + CHECK_MPI_OK(mp_div(&kphi, &tmp, &kphi, &r)); + if (mp_cmp_z(&r) != 0) { + /* p-1 doesn't divide kphi, some parameter wasn't correct */ + err = MP_RANGE; + goto cleanup; + } + mp_zero(q); + /* kphi is now k*(q-1) */ + + /* rest of the for loop */ + for (; (err == MP_OKAY) && (mpl_significant_bits(&k) >= order_k); + err = mp_sub_d(&k, 1, &k)) { + CHECK_MPI_OK(err); + /* looking for k as a factor of kphi */ + CHECK_MPI_OK(mp_div(&kphi, &k, &phi, &r)); + if (mp_cmp_z(&r) != 0) { + /* not a factor, try the next one */ + continue; + } + /* we have a possible phi, see if it works */ + if ((unsigned)mpl_significant_bits(&phi) != keySizeInBits / 2) { + /* phi is not the right size */ + continue; + } + /* phi should be divisible by 2, since + * q is odd and phi=(q-1). */ + if (mpp_divis_d(&phi, 2) == MP_NO) { + /* phi is not divisible by 4 */ + continue; + } + /* we now have a candidate for the second prime */ + CHECK_MPI_OK(mp_add_d(&phi, 1, &tmp)); + + /* check to make sure it is prime */ + err = rsa_is_prime(&tmp); + if (err != MP_OKAY) { + if (err == MP_NO) { + /* No, then we still have the wrong phi */ + continue; + } + goto cleanup; + } + /* + * It is possible that we have the wrong phi if + * k_guess*(q_guess-1) = k*(q-1) (k and q-1 have swapped factors). + * since our q_quess is prime, however. We have found a valid + * rsa key because: + * q is the correct order of magnitude. + * phi = (p-1)(q-1) where p and q are both primes. + * e*d mod phi = 1. + * There is no way to know from the info given if this is the + * original key. We never want to return the wrong key because if + * two moduli with the same factor is known, then euclid's gcd + * algorithm can be used to find that factor. Even though the + * caller didn't pass the original modulus, it doesn't mean the + * modulus wasn't known or isn't available somewhere. So to be safe + * if we can't be sure we have the right q, we don't return any. + * + * So to make sure we continue looking for other valid q's. If none + * are found, then we can safely return this one, otherwise we just + * fail */ + if (mp_cmp_z(q) != 0) { + /* this is the second valid q, don't return either, + * just fail */ + err = MP_RANGE; + break; + } + /* we only have one q so far, save it and if no others are found, + * it's safe to return it */ + CHECK_MPI_OK(mp_copy(&tmp, q)); + continue; + } + if ((unsigned)mpl_significant_bits(&k) < order_k) { + if (mp_cmp_z(q) == 0) { + /* If we get here, something was wrong with the parameters we + * were given */ + err = MP_RANGE; + } + } +cleanup: + mp_clear(&kphi); + mp_clear(&phi); + mp_clear(&k); + mp_clear(&r); + mp_clear(&tmp); + return err; +} + +/* + * take a private key with only a few elements and fill out the missing pieces. + * + * All the entries will be overwritten with data allocated out of the arena + * If no arena is supplied, one will be created. + * + * The following fields must be supplied in order for this function + * to succeed: + * one of either publicExponent or privateExponent + * two more of the following 5 parameters. + * modulus (n) + * prime1 (p) + * prime2 (q) + * publicExponent (e) + * privateExponent (d) + * + * NOTE: if only the publicExponent, privateExponent, and one prime is given, + * then there may be more than one RSA key that matches that combination. + * + * All parameters will be replaced in the key structure with new parameters + * Allocated out of the arena. There is no attempt to free the old structures. + * Prime1 will always be greater than prime2 (even if the caller supplies the + * smaller prime as prime1 or the larger prime as prime2). The parameters are + * not overwritten on failure. + * + * How it works: + * We can generate all the parameters from one of the exponents, plus the + * two primes. (rsa_build_key_from_primes) + * If we are given one of the exponents and both primes, we are done. + * If we are given one of the exponents, the modulus and one prime, we + * caclulate the second prime by dividing the modulus by the given + * prime, giving us an exponent and 2 primes. + * If we are given 2 exponents and one of the primes we calculate + * k*phi = d*e-1, where k is an integer less than d which + * divides d*e-1. We find factor k so we can isolate phi. + * phi = (p-1)(q-1) + * We can use phi to find the other prime as follows: + * q = (phi/(p-1)) + 1. We now have 2 primes and an exponent. + * (NOTE: if more then one prime meets this condition, the operation + * will fail. See comments elsewhere in this file about this). + * (rsa_get_prime_from_exponents) + * If we are given 2 exponents and the modulus we factor the modulus to + * get the 2 missing primes (rsa_factorize_n_from_exponents) + * + */ +SECStatus +RSA_PopulatePrivateKey(RSAPrivateKey *key) +{ + PLArenaPool *arena = NULL; + PRBool needPublicExponent = PR_TRUE; + PRBool needPrivateExponent = PR_TRUE; + PRBool hasModulus = PR_FALSE; + unsigned int keySizeInBits = 0; + int prime_count = 0; + /* standard RSA nominclature */ + mp_int p, q, e, d, n; + /* remainder */ + mp_int r; + mp_err err = 0; + SECStatus rv = SECFailure; + + MP_DIGITS(&p) = 0; + MP_DIGITS(&q) = 0; + MP_DIGITS(&e) = 0; + MP_DIGITS(&d) = 0; + MP_DIGITS(&n) = 0; + MP_DIGITS(&r) = 0; + CHECK_MPI_OK(mp_init(&p)); + CHECK_MPI_OK(mp_init(&q)); + CHECK_MPI_OK(mp_init(&e)); + CHECK_MPI_OK(mp_init(&d)); + CHECK_MPI_OK(mp_init(&n)); + CHECK_MPI_OK(mp_init(&r)); + + /* if the key didn't already have an arena, create one. */ + if (key->arena == NULL) { + arena = PORT_NewArena(NSS_FREEBL_DEFAULT_CHUNKSIZE); + if (!arena) { + goto cleanup; + } + key->arena = arena; + } + + /* load up the known exponents */ + if (key->publicExponent.data) { + SECITEM_TO_MPINT(key->publicExponent, &e); + needPublicExponent = PR_FALSE; + } + if (key->privateExponent.data) { + SECITEM_TO_MPINT(key->privateExponent, &d); + needPrivateExponent = PR_FALSE; + } + if (needPrivateExponent && needPublicExponent) { + /* Not enough information, we need at least one exponent */ + err = MP_BADARG; + goto cleanup; + } + + /* load up the known primes. If only one prime is given, it will be + * assigned 'p'. Once we have both primes, well make sure p is the larger. + * The value prime_count tells us howe many we have acquired. + */ + if (key->prime1.data) { + int primeLen = key->prime1.len; + if (key->prime1.data[0] == 0) { + primeLen--; + } + keySizeInBits = primeLen * 2 * PR_BITS_PER_BYTE; + SECITEM_TO_MPINT(key->prime1, &p); + prime_count++; + } + if (key->prime2.data) { + int primeLen = key->prime2.len; + if (key->prime2.data[0] == 0) { + primeLen--; + } + keySizeInBits = primeLen * 2 * PR_BITS_PER_BYTE; + SECITEM_TO_MPINT(key->prime2, prime_count ? &q : &p); + prime_count++; + } + /* load up the modulus */ + if (key->modulus.data) { + int modLen = key->modulus.len; + if (key->modulus.data[0] == 0) { + modLen--; + } + keySizeInBits = modLen * PR_BITS_PER_BYTE; + SECITEM_TO_MPINT(key->modulus, &n); + hasModulus = PR_TRUE; + } + /* if we have the modulus and one prime, calculate the second. */ + if ((prime_count == 1) && (hasModulus)) { + if (mp_div(&n, &p, &q, &r) != MP_OKAY || mp_cmp_z(&r) != 0) { + /* p is not a factor or n, fail */ + err = MP_BADARG; + goto cleanup; + } + prime_count++; + } + + /* If we didn't have enough primes try to calculate the primes from + * the exponents */ + if (prime_count < 2) { + /* if we don't have at least 2 primes at this point, then we need both + * exponents and one prime or a modulus*/ + if (!needPublicExponent && !needPrivateExponent && + (prime_count > 0)) { + CHECK_MPI_OK(rsa_get_prime_from_exponents(&e, &d, &p, &q, &n, + keySizeInBits)); + } else if (!needPublicExponent && !needPrivateExponent && hasModulus) { + CHECK_MPI_OK(rsa_factorize_n_from_exponents(&e, &d, &p, &q, &n)); + } else { + /* not enough given parameters to get both primes */ + err = MP_BADARG; + goto cleanup; + } + } + + /* Assure p > q */ + /* NOTE: PKCS #1 does not require p > q, and NSS doesn't use any + * implementation optimization that requires p > q. We can remove + * this code in the future. + */ + if (mp_cmp(&p, &q) < 0) + mp_exch(&p, &q); + + /* we now have our 2 primes and at least one exponent, we can fill + * in the key */ + rv = rsa_build_from_primes(&p, &q, + &e, needPublicExponent, + &d, needPrivateExponent, + key, keySizeInBits); +cleanup: + mp_clear(&p); + mp_clear(&q); + mp_clear(&e); + mp_clear(&d); + mp_clear(&n); + mp_clear(&r); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + if (rv && arena) { + PORT_FreeArena(arena, PR_TRUE); + key->arena = NULL; + } + return rv; +} + +static unsigned int +rsa_modulusLen(SECItem *modulus) +{ + if (modulus->len == 0) { + return 0; + }; + unsigned char byteZero = modulus->data[0]; + unsigned int modLen = modulus->len - !byteZero; + return modLen; +} + +/* +** Perform a raw public-key operation +** Length of input and output buffers are equal to key's modulus len. +*/ +SECStatus +RSA_PublicKeyOp(RSAPublicKey *key, + unsigned char *output, + const unsigned char *input) +{ + unsigned int modLen, expLen, offset; + mp_int n, e, m, c; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + if (!key || !output || !input) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + MP_DIGITS(&n) = 0; + MP_DIGITS(&e) = 0; + MP_DIGITS(&m) = 0; + MP_DIGITS(&c) = 0; + CHECK_MPI_OK(mp_init(&n)); + CHECK_MPI_OK(mp_init(&e)); + CHECK_MPI_OK(mp_init(&m)); + CHECK_MPI_OK(mp_init(&c)); + modLen = rsa_modulusLen(&key->modulus); + expLen = rsa_modulusLen(&key->publicExponent); + + if (modLen == 0) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + rv = SECFailure; + goto cleanup; + } + + /* 1. Obtain public key (n, e) */ + if (BAD_RSA_KEY_SIZE(modLen, expLen)) { + PORT_SetError(SEC_ERROR_INVALID_KEY); + rv = SECFailure; + goto cleanup; + } + SECITEM_TO_MPINT(key->modulus, &n); + SECITEM_TO_MPINT(key->publicExponent, &e); + if (e.used > n.used) { + /* exponent should not be greater than modulus */ + PORT_SetError(SEC_ERROR_INVALID_KEY); + rv = SECFailure; + goto cleanup; + } + /* 2. check input out of range (needs to be in range [0..n-1]) */ + offset = (key->modulus.data[0] == 0) ? 1 : 0; /* may be leading 0 */ + if (memcmp(input, key->modulus.data + offset, modLen) >= 0) { + PORT_SetError(SEC_ERROR_INPUT_LEN); + rv = SECFailure; + goto cleanup; + } + /* 2 bis. Represent message as integer in range [0..n-1] */ + CHECK_MPI_OK(mp_read_unsigned_octets(&m, input, modLen)); +/* 3. Compute c = m**e mod n */ +#ifdef USE_MPI_EXPT_D + /* XXX see which is faster */ + if (MP_USED(&e) == 1) { + CHECK_MPI_OK(mp_exptmod_d(&m, MP_DIGIT(&e, 0), &n, &c)); + } else +#endif + CHECK_MPI_OK(mp_exptmod(&m, &e, &n, &c)); + /* 4. result c is ciphertext */ + err = mp_to_fixlen_octets(&c, output, modLen); + if (err >= 0) + err = MP_OKAY; +cleanup: + mp_clear(&n); + mp_clear(&e); + mp_clear(&m); + mp_clear(&c); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +/* +** RSA Private key operation (no CRT). +*/ +static SECStatus +rsa_PrivateKeyOpNoCRT(RSAPrivateKey *key, mp_int *m, mp_int *c, mp_int *n, + unsigned int modLen) +{ + mp_int d; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + MP_DIGITS(&d) = 0; + CHECK_MPI_OK(mp_init(&d)); + SECITEM_TO_MPINT(key->privateExponent, &d); + /* 1. m = c**d mod n */ + CHECK_MPI_OK(mp_exptmod(c, &d, n, m)); +cleanup: + mp_clear(&d); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +/* +** RSA Private key operation using CRT. +*/ +static SECStatus +rsa_PrivateKeyOpCRTNoCheck(RSAPrivateKey *key, mp_int *m, mp_int *c) +{ + mp_int p, q, d_p, d_q, qInv; + /* + The length of the randomness comes from the papers: + https://link.springer.com/chapter/10.1007/978-3-642-29912-4_7 + https://link.springer.com/chapter/10.1007/978-3-642-21554-4_5. + */ + mp_int blinding_dp, blinding_dq, r1, r2; + unsigned char random_block[EXP_BLINDING_RANDOMNESS_LEN_BYTES]; + mp_int m1, m2, h, ctmp; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + MP_DIGITS(&p) = 0; + MP_DIGITS(&q) = 0; + MP_DIGITS(&d_p) = 0; + MP_DIGITS(&d_q) = 0; + MP_DIGITS(&qInv) = 0; + MP_DIGITS(&m1) = 0; + MP_DIGITS(&m2) = 0; + MP_DIGITS(&h) = 0; + MP_DIGITS(&ctmp) = 0; + MP_DIGITS(&blinding_dp) = 0; + MP_DIGITS(&blinding_dq) = 0; + MP_DIGITS(&r1) = 0; + MP_DIGITS(&r2) = 0; + + CHECK_MPI_OK(mp_init(&p)); + CHECK_MPI_OK(mp_init(&q)); + CHECK_MPI_OK(mp_init(&d_p)); + CHECK_MPI_OK(mp_init(&d_q)); + CHECK_MPI_OK(mp_init(&qInv)); + CHECK_MPI_OK(mp_init(&m1)); + CHECK_MPI_OK(mp_init(&m2)); + CHECK_MPI_OK(mp_init(&h)); + CHECK_MPI_OK(mp_init(&ctmp)); + CHECK_MPI_OK(mp_init(&blinding_dp)); + CHECK_MPI_OK(mp_init(&blinding_dq)); + CHECK_MPI_OK(mp_init_size(&r1, EXP_BLINDING_RANDOMNESS_LEN)); + CHECK_MPI_OK(mp_init_size(&r2, EXP_BLINDING_RANDOMNESS_LEN)); + + /* copy private key parameters into mp integers */ + SECITEM_TO_MPINT(key->prime1, &p); /* p */ + SECITEM_TO_MPINT(key->prime2, &q); /* q */ + SECITEM_TO_MPINT(key->exponent1, &d_p); /* d_p = d mod (p-1) */ + SECITEM_TO_MPINT(key->exponent2, &d_q); /* d_q = d mod (q-1) */ + SECITEM_TO_MPINT(key->coefficient, &qInv); /* qInv = q**-1 mod p */ + + // blinding_dp = 1 + CHECK_MPI_OK(mp_set_int(&blinding_dp, 1)); + // blinding_dp = p - 1 + CHECK_MPI_OK(mp_sub(&p, &blinding_dp, &blinding_dp)); + // generating a random value + RNG_GenerateGlobalRandomBytes(random_block, EXP_BLINDING_RANDOMNESS_LEN_BYTES); + MP_USED(&r1) = EXP_BLINDING_RANDOMNESS_LEN; + memcpy(MP_DIGITS(&r1), random_block, sizeof(random_block)); + // blinding_dp = random * (p - 1) + CHECK_MPI_OK(mp_mul(&blinding_dp, &r1, &blinding_dp)); + //d_p = d_p + random * (p - 1) + CHECK_MPI_OK(mp_add(&d_p, &blinding_dp, &d_p)); + + // blinding_dq = 1 + CHECK_MPI_OK(mp_set_int(&blinding_dq, 1)); + // blinding_dq = q - 1 + CHECK_MPI_OK(mp_sub(&q, &blinding_dq, &blinding_dq)); + // generating a random value + RNG_GenerateGlobalRandomBytes(random_block, EXP_BLINDING_RANDOMNESS_LEN_BYTES); + memcpy(MP_DIGITS(&r2), random_block, sizeof(random_block)); + MP_USED(&r2) = EXP_BLINDING_RANDOMNESS_LEN; + // blinding_dq = random * (q - 1) + CHECK_MPI_OK(mp_mul(&blinding_dq, &r2, &blinding_dq)); + //d_q = d_q + random * (q-1) + CHECK_MPI_OK(mp_add(&d_q, &blinding_dq, &d_q)); + + /* 1. m1 = c**d_p mod p */ + CHECK_MPI_OK(mp_mod(c, &p, &ctmp)); + CHECK_MPI_OK(mp_exptmod(&ctmp, &d_p, &p, &m1)); + /* 2. m2 = c**d_q mod q */ + CHECK_MPI_OK(mp_mod(c, &q, &ctmp)); + CHECK_MPI_OK(mp_exptmod(&ctmp, &d_q, &q, &m2)); + /* 3. h = (m1 - m2) * qInv mod p */ + CHECK_MPI_OK(mp_submod(&m1, &m2, &p, &h)); + CHECK_MPI_OK(mp_mulmod(&h, &qInv, &p, &h)); + /* 4. m = m2 + h * q */ + CHECK_MPI_OK(mp_mul(&h, &q, m)); + CHECK_MPI_OK(mp_add(m, &m2, m)); +cleanup: + mp_clear(&p); + mp_clear(&q); + mp_clear(&d_p); + mp_clear(&d_q); + mp_clear(&qInv); + mp_clear(&m1); + mp_clear(&m2); + mp_clear(&h); + mp_clear(&ctmp); + mp_clear(&blinding_dp); + mp_clear(&blinding_dq); + mp_clear(&r1); + mp_clear(&r2); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +/* +** An attack against RSA CRT was described by Boneh, DeMillo, and Lipton in: +** "On the Importance of Eliminating Errors in Cryptographic Computations", +** http://theory.stanford.edu/~dabo/papers/faults.ps.gz +** +** As a defense against the attack, carry out the private key operation, +** followed up with a public key operation to invert the result. +** Verify that result against the input. +*/ +static SECStatus +rsa_PrivateKeyOpCRTCheckedPubKey(RSAPrivateKey *key, mp_int *m, mp_int *c) +{ + mp_int n, e, v; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + MP_DIGITS(&n) = 0; + MP_DIGITS(&e) = 0; + MP_DIGITS(&v) = 0; + CHECK_MPI_OK(mp_init(&n)); + CHECK_MPI_OK(mp_init(&e)); + CHECK_MPI_OK(mp_init(&v)); + CHECK_SEC_OK(rsa_PrivateKeyOpCRTNoCheck(key, m, c)); + SECITEM_TO_MPINT(key->modulus, &n); + SECITEM_TO_MPINT(key->publicExponent, &e); + /* Perform a public key operation v = m ** e mod n */ + CHECK_MPI_OK(mp_exptmod(m, &e, &n, &v)); + if (mp_cmp(&v, c) != 0) { + rv = SECFailure; + } +cleanup: + mp_clear(&n); + mp_clear(&e); + mp_clear(&v); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +static PRCallOnceType coBPInit = { 0, 0, 0 }; +static PRStatus +init_blinding_params_list(void) +{ + blindingParamsList.lock = PZ_NewLock(nssILockOther); + if (!blindingParamsList.lock) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + return PR_FAILURE; + } + blindingParamsList.cVar = PR_NewCondVar(blindingParamsList.lock); + if (!blindingParamsList.cVar) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + return PR_FAILURE; + } + blindingParamsList.waitCount = 0; + PR_INIT_CLIST(&blindingParamsList.head); + return PR_SUCCESS; +} + +static SECStatus +generate_blinding_params(RSAPrivateKey *key, mp_int *f, mp_int *g, mp_int *n, + unsigned int modLen) +{ + SECStatus rv = SECSuccess; + mp_int e, k; + mp_err err = MP_OKAY; + unsigned char *kb = NULL; + + MP_DIGITS(&e) = 0; + MP_DIGITS(&k) = 0; + CHECK_MPI_OK(mp_init(&e)); + CHECK_MPI_OK(mp_init(&k)); + SECITEM_TO_MPINT(key->publicExponent, &e); + /* generate random k < n */ + kb = PORT_Alloc(modLen); + if (!kb) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + goto cleanup; + } + CHECK_SEC_OK(RNG_GenerateGlobalRandomBytes(kb, modLen)); + CHECK_MPI_OK(mp_read_unsigned_octets(&k, kb, modLen)); + /* k < n */ + CHECK_MPI_OK(mp_mod(&k, n, &k)); + /* f = k**e mod n */ + CHECK_MPI_OK(mp_exptmod(&k, &e, n, f)); + /* g = k**-1 mod n */ + CHECK_MPI_OK(mp_invmod(&k, n, g)); + /* g in montgomery form.. */ + CHECK_MPI_OK(mp_to_mont(g, n, g)); +cleanup: + if (kb) + PORT_ZFree(kb, modLen); + mp_clear(&k); + mp_clear(&e); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +static SECStatus +init_blinding_params(RSABlindingParams *rsabp, RSAPrivateKey *key, + mp_int *n, unsigned int modLen) +{ + blindingParams *bp = rsabp->array; + int i = 0; + + /* Initialize the list pointer for the element */ + PR_INIT_CLIST(&rsabp->link); + for (i = 0; i < RSA_BLINDING_PARAMS_MAX_CACHE_SIZE; ++i, ++bp) { + bp->next = bp + 1; + MP_DIGITS(&bp->f) = 0; + MP_DIGITS(&bp->g) = 0; + bp->counter = 0; + } + /* The last bp->next value was initialized with out + * of rsabp->array pointer and must be set to NULL + */ + rsabp->array[RSA_BLINDING_PARAMS_MAX_CACHE_SIZE - 1].next = NULL; + + bp = rsabp->array; + rsabp->bp = NULL; + rsabp->free = bp; + + /* precalculate montgomery reduction parameter */ + rsabp->n0i = mp_calculate_mont_n0i(n); + + /* List elements are keyed using the modulus */ + return SECITEM_CopyItem(NULL, &rsabp->modulus, &key->modulus); +} + +static SECStatus +get_blinding_params(RSAPrivateKey *key, mp_int *n, unsigned int modLen, + mp_int *f, mp_int *g, mp_digit *n0i) +{ + RSABlindingParams *rsabp = NULL; + blindingParams *bpUnlinked = NULL; + blindingParams *bp; + PRCList *el; + SECStatus rv = SECSuccess; + mp_err err = MP_OKAY; + int cmp = -1; + PRBool holdingLock = PR_FALSE; + + do { + if (blindingParamsList.lock == NULL) { + PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); + return SECFailure; + } + /* Acquire the list lock */ + PZ_Lock(blindingParamsList.lock); + holdingLock = PR_TRUE; + + /* Walk the list looking for the private key */ + for (el = PR_NEXT_LINK(&blindingParamsList.head); + el != &blindingParamsList.head; + el = PR_NEXT_LINK(el)) { + rsabp = (RSABlindingParams *)el; + cmp = SECITEM_CompareItem(&rsabp->modulus, &key->modulus); + if (cmp >= 0) { + /* The key is found or not in the list. */ + break; + } + } + + if (cmp) { + /* At this point, the key is not in the list. el should point to + ** the list element before which this key should be inserted. + */ + rsabp = PORT_ZNew(RSABlindingParams); + if (!rsabp) { + PORT_SetError(SEC_ERROR_NO_MEMORY); + goto cleanup; + } + + rv = init_blinding_params(rsabp, key, n, modLen); + if (rv != SECSuccess) { + PORT_ZFree(rsabp, sizeof(RSABlindingParams)); + goto cleanup; + } + + /* Insert the new element into the list + ** If inserting in the middle of the list, el points to the link + ** to insert before. Otherwise, the link needs to be appended to + ** the end of the list, which is the same as inserting before the + ** head (since el would have looped back to the head). + */ + PR_INSERT_BEFORE(&rsabp->link, el); + } + + /* We've found (or created) the RSAblindingParams struct for this key. + * Now, search its list of ready blinding params for a usable one. + */ + *n0i = rsabp->n0i; + while (0 != (bp = rsabp->bp)) { +#ifdef UNSAFE_FUZZER_MODE + /* Found a match and there are still remaining uses left */ + /* Return the parameters */ + CHECK_MPI_OK(mp_copy(&bp->f, f)); + CHECK_MPI_OK(mp_copy(&bp->g, g)); + + PZ_Unlock(blindingParamsList.lock); + return SECSuccess; +#else + if (--(bp->counter) > 0) { + /* Found a match and there are still remaining uses left */ + /* Return the parameters */ + CHECK_MPI_OK(mp_copy(&bp->f, f)); + CHECK_MPI_OK(mp_copy(&bp->g, g)); + + PZ_Unlock(blindingParamsList.lock); + return SECSuccess; + } + /* exhausted this one, give its values to caller, and + * then retire it. + */ + mp_exch(&bp->f, f); + mp_exch(&bp->g, g); + mp_clear(&bp->f); + mp_clear(&bp->g); + bp->counter = 0; + /* Move to free list */ + rsabp->bp = bp->next; + bp->next = rsabp->free; + rsabp->free = bp; + /* In case there're threads waiting for new blinding + * value - notify 1 thread the value is ready + */ + if (blindingParamsList.waitCount > 0) { + PR_NotifyCondVar(blindingParamsList.cVar); + blindingParamsList.waitCount--; + } + PZ_Unlock(blindingParamsList.lock); + return SECSuccess; +#endif + } + /* We did not find a usable set of blinding params. Can we make one? */ + /* Find a free bp struct. */ + if ((bp = rsabp->free) != NULL) { + /* unlink this bp */ + rsabp->free = bp->next; + bp->next = NULL; + bpUnlinked = bp; /* In case we fail */ + + PZ_Unlock(blindingParamsList.lock); + holdingLock = PR_FALSE; + /* generate blinding parameter values for the current thread */ + CHECK_SEC_OK(generate_blinding_params(key, f, g, n, modLen)); + + /* put the blinding parameter values into cache */ + CHECK_MPI_OK(mp_init(&bp->f)); + CHECK_MPI_OK(mp_init(&bp->g)); + CHECK_MPI_OK(mp_copy(f, &bp->f)); + CHECK_MPI_OK(mp_copy(g, &bp->g)); + + /* Put this at head of queue of usable params. */ + PZ_Lock(blindingParamsList.lock); + holdingLock = PR_TRUE; + (void)holdingLock; + /* initialize RSABlindingParamsStr */ + bp->counter = RSA_BLINDING_PARAMS_MAX_REUSE; + bp->next = rsabp->bp; + rsabp->bp = bp; + bpUnlinked = NULL; + /* In case there're threads waiting for new blinding value + * just notify them the value is ready + */ + if (blindingParamsList.waitCount > 0) { + PR_NotifyAllCondVar(blindingParamsList.cVar); + blindingParamsList.waitCount = 0; + } + PZ_Unlock(blindingParamsList.lock); + return SECSuccess; + } + /* Here, there are no usable blinding parameters available, + * and no free bp blocks, presumably because they're all + * actively having parameters generated for them. + * So, we need to wait here and not eat up CPU until some + * change happens. + */ + blindingParamsList.waitCount++; + PR_WaitCondVar(blindingParamsList.cVar, PR_INTERVAL_NO_TIMEOUT); + PZ_Unlock(blindingParamsList.lock); + holdingLock = PR_FALSE; + (void)holdingLock; + } while (1); + +cleanup: + /* It is possible to reach this after the lock is already released. */ + if (bpUnlinked) { + if (!holdingLock) { + PZ_Lock(blindingParamsList.lock); + holdingLock = PR_TRUE; + } + bp = bpUnlinked; + mp_clear(&bp->f); + mp_clear(&bp->g); + bp->counter = 0; + /* Must put the unlinked bp back on the free list */ + bp->next = rsabp->free; + rsabp->free = bp; + } + if (holdingLock) { + PZ_Unlock(blindingParamsList.lock); + } + if (err) { + MP_TO_SEC_ERROR(err); + } + *n0i = 0; + return SECFailure; +} + +/* +** Perform a raw private-key operation +** Length of input and output buffers are equal to key's modulus len. +*/ +static SECStatus +rsa_PrivateKeyOp(RSAPrivateKey *key, + unsigned char *output, + const unsigned char *input, + PRBool check) +{ + unsigned int modLen; + unsigned int offset; + SECStatus rv = SECSuccess; + mp_err err; + mp_int n, c, m; + mp_int f, g; + mp_digit n0i; + if (!key || !output || !input) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + /* check input out of range (needs to be in range [0..n-1]) */ + modLen = rsa_modulusLen(&key->modulus); + if (modLen == 0) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + offset = (key->modulus.data[0] == 0) ? 1 : 0; /* may be leading 0 */ + if (memcmp(input, key->modulus.data + offset, modLen) >= 0) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + MP_DIGITS(&n) = 0; + MP_DIGITS(&c) = 0; + MP_DIGITS(&m) = 0; + MP_DIGITS(&f) = 0; + MP_DIGITS(&g) = 0; + CHECK_MPI_OK(mp_init(&n)); + CHECK_MPI_OK(mp_init(&c)); + CHECK_MPI_OK(mp_init(&m)); + CHECK_MPI_OK(mp_init(&f)); + CHECK_MPI_OK(mp_init(&g)); + SECITEM_TO_MPINT(key->modulus, &n); + OCTETS_TO_MPINT(input, &c, modLen); + /* If blinding, compute pre-image of ciphertext by multiplying by + ** blinding factor + */ + if (nssRSAUseBlinding) { + CHECK_SEC_OK(get_blinding_params(key, &n, modLen, &f, &g, &n0i)); + /* c' = c*f mod n */ + CHECK_MPI_OK(mp_mulmod(&c, &f, &n, &c)); + } + /* Do the private key operation m = c**d mod n */ + if (key->prime1.len == 0 || + key->prime2.len == 0 || + key->exponent1.len == 0 || + key->exponent2.len == 0 || + key->coefficient.len == 0) { + CHECK_SEC_OK(rsa_PrivateKeyOpNoCRT(key, &m, &c, &n, modLen)); + } else if (check) { + CHECK_SEC_OK(rsa_PrivateKeyOpCRTCheckedPubKey(key, &m, &c)); + } else { + CHECK_SEC_OK(rsa_PrivateKeyOpCRTNoCheck(key, &m, &c)); + } + /* If blinding, compute post-image of plaintext by multiplying by + ** blinding factor + */ + if (nssRSAUseBlinding) { + /* m = m'*g mod n */ + CHECK_MPI_OK(mp_mulmontmodCT(&m, &g, &n, n0i, &m)); + } + err = mp_to_fixlen_octets(&m, output, modLen); + if (err >= 0) + err = MP_OKAY; +cleanup: + mp_clear(&n); + mp_clear(&c); + mp_clear(&m); + mp_clear(&f); + mp_clear(&g); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +SECStatus +RSA_PrivateKeyOp(RSAPrivateKey *key, + unsigned char *output, + const unsigned char *input) +{ + return rsa_PrivateKeyOp(key, output, input, PR_FALSE); +} + +SECStatus +RSA_PrivateKeyOpDoubleChecked(RSAPrivateKey *key, + unsigned char *output, + const unsigned char *input) +{ + return rsa_PrivateKeyOp(key, output, input, PR_TRUE); +} + +SECStatus +RSA_PrivateKeyCheck(const RSAPrivateKey *key) +{ + mp_int p, q, n, psub1, qsub1, e, d, d_p, d_q, qInv, res; + mp_err err = MP_OKAY; + SECStatus rv = SECSuccess; + MP_DIGITS(&p) = 0; + MP_DIGITS(&q) = 0; + MP_DIGITS(&n) = 0; + MP_DIGITS(&psub1) = 0; + MP_DIGITS(&qsub1) = 0; + MP_DIGITS(&e) = 0; + MP_DIGITS(&d) = 0; + MP_DIGITS(&d_p) = 0; + MP_DIGITS(&d_q) = 0; + MP_DIGITS(&qInv) = 0; + MP_DIGITS(&res) = 0; + CHECK_MPI_OK(mp_init(&p)); + CHECK_MPI_OK(mp_init(&q)); + CHECK_MPI_OK(mp_init(&n)); + CHECK_MPI_OK(mp_init(&psub1)); + CHECK_MPI_OK(mp_init(&qsub1)); + CHECK_MPI_OK(mp_init(&e)); + CHECK_MPI_OK(mp_init(&d)); + CHECK_MPI_OK(mp_init(&d_p)); + CHECK_MPI_OK(mp_init(&d_q)); + CHECK_MPI_OK(mp_init(&qInv)); + CHECK_MPI_OK(mp_init(&res)); + + if (!key->modulus.data || !key->prime1.data || !key->prime2.data || + !key->publicExponent.data || !key->privateExponent.data || + !key->exponent1.data || !key->exponent2.data || + !key->coefficient.data) { + /* call RSA_PopulatePrivateKey first, if the application wishes to + * recover these parameters */ + err = MP_BADARG; + goto cleanup; + } + + SECITEM_TO_MPINT(key->modulus, &n); + SECITEM_TO_MPINT(key->prime1, &p); + SECITEM_TO_MPINT(key->prime2, &q); + SECITEM_TO_MPINT(key->publicExponent, &e); + SECITEM_TO_MPINT(key->privateExponent, &d); + SECITEM_TO_MPINT(key->exponent1, &d_p); + SECITEM_TO_MPINT(key->exponent2, &d_q); + SECITEM_TO_MPINT(key->coefficient, &qInv); + /* p and q must be distinct. */ + if (mp_cmp(&p, &q) == 0) { + rv = SECFailure; + goto cleanup; + } +#define VERIFY_MPI_EQUAL(m1, m2) \ + if (mp_cmp(m1, m2) != 0) { \ + rv = SECFailure; \ + goto cleanup; \ + } +#define VERIFY_MPI_EQUAL_1(m) \ + if (mp_cmp_d(m, 1) != 0) { \ + rv = SECFailure; \ + goto cleanup; \ + } + /* n == p * q */ + CHECK_MPI_OK(mp_mul(&p, &q, &res)); + VERIFY_MPI_EQUAL(&res, &n); + /* gcd(e, p-1) == 1 */ + CHECK_MPI_OK(mp_sub_d(&p, 1, &psub1)); + CHECK_MPI_OK(mp_gcd(&e, &psub1, &res)); + VERIFY_MPI_EQUAL_1(&res); + /* gcd(e, q-1) == 1 */ + CHECK_MPI_OK(mp_sub_d(&q, 1, &qsub1)); + CHECK_MPI_OK(mp_gcd(&e, &qsub1, &res)); + VERIFY_MPI_EQUAL_1(&res); + /* d*e == 1 mod p-1 */ + CHECK_MPI_OK(mp_mulmod(&d, &e, &psub1, &res)); + VERIFY_MPI_EQUAL_1(&res); + /* d*e == 1 mod q-1 */ + CHECK_MPI_OK(mp_mulmod(&d, &e, &qsub1, &res)); + VERIFY_MPI_EQUAL_1(&res); + /* d_p == d mod p-1 */ + CHECK_MPI_OK(mp_mod(&d, &psub1, &res)); + VERIFY_MPI_EQUAL(&res, &d_p); + /* d_q == d mod q-1 */ + CHECK_MPI_OK(mp_mod(&d, &qsub1, &res)); + VERIFY_MPI_EQUAL(&res, &d_q); + /* q * q**-1 == 1 mod p */ + CHECK_MPI_OK(mp_mulmod(&q, &qInv, &p, &res)); + VERIFY_MPI_EQUAL_1(&res); + +cleanup: + mp_clear(&n); + mp_clear(&p); + mp_clear(&q); + mp_clear(&psub1); + mp_clear(&qsub1); + mp_clear(&e); + mp_clear(&d); + mp_clear(&d_p); + mp_clear(&d_q); + mp_clear(&qInv); + mp_clear(&res); + if (err) { + MP_TO_SEC_ERROR(err); + rv = SECFailure; + } + return rv; +} + +SECStatus +RSA_Init(void) +{ + if (PR_CallOnce(&coBPInit, init_blinding_params_list) != PR_SUCCESS) { + PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); + return SECFailure; + } + return SECSuccess; +} + +/* cleanup at shutdown */ +void +RSA_Cleanup(void) +{ + blindingParams *bp = NULL; + if (!coBPInit.initialized) + return; + + while (!PR_CLIST_IS_EMPTY(&blindingParamsList.head)) { + RSABlindingParams *rsabp = + (RSABlindingParams *)PR_LIST_HEAD(&blindingParamsList.head); + PR_REMOVE_LINK(&rsabp->link); + /* clear parameters cache */ + while (rsabp->bp != NULL) { + bp = rsabp->bp; + rsabp->bp = rsabp->bp->next; + mp_clear(&bp->f); + mp_clear(&bp->g); + } + SECITEM_ZfreeItem(&rsabp->modulus, PR_FALSE); + PORT_Free(rsabp); + } + + if (blindingParamsList.cVar) { + PR_DestroyCondVar(blindingParamsList.cVar); + blindingParamsList.cVar = NULL; + } + + if (blindingParamsList.lock) { + SKIP_AFTER_FORK(PZ_DestroyLock(blindingParamsList.lock)); + blindingParamsList.lock = NULL; + } + + coBPInit.initialized = 0; + coBPInit.inProgress = 0; + coBPInit.status = 0; +} + +/* + * need a central place for this function to free up all the memory that + * free_bl may have allocated along the way. Currently only RSA does this, + * so I've put it here for now. + */ +void +BL_Cleanup(void) +{ + RSA_Cleanup(); +} + +PRBool bl_parentForkedAfterC_Initialize; + +/* + * Set fork flag so it can be tested in SKIP_AFTER_FORK on relevant platforms. + */ +void +BL_SetForkState(PRBool forked) +{ + bl_parentForkedAfterC_Initialize = forked; +} |