static int
dsa_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
{
const unsigned char *p, *pm;
int pklen, pmlen;
int ptype;
void *pval;
ASN1_STRING *pstr;
X509_ALGOR *palg;
ASN1_INTEGER *privkey = NULL;
BN_CTX *ctx = NULL;
STACK_OF(ASN1_TYPE) *ndsa = NULL;
DSA *dsa = NULL;
if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
return 0;
X509_ALGOR_get0(NULL, &ptype, &pval, palg);
/* Check for broken DSA PKCS#8, UGH! */
if (*p == (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED)) {
ASN1_TYPE *t1, *t2;
if (!(ndsa = d2i_ASN1_SEQUENCE_ANY(NULL, &p, pklen)))
goto decerr;
if (sk_ASN1_TYPE_num(ndsa) != 2)
goto decerr;
/*
* Handle Two broken types:
* SEQUENCE {parameters, priv_key}
* SEQUENCE {pub_key, priv_key}
*/
t1 = sk_ASN1_TYPE_value(ndsa, 0);
t2 = sk_ASN1_TYPE_value(ndsa, 1);
if (t1->type == V_ASN1_SEQUENCE) {
p8->broken = PKCS8_EMBEDDED_PARAM;
pval = t1->value.ptr;
} else if (ptype == V_ASN1_SEQUENCE)
p8->broken = PKCS8_NS_DB;
else
goto decerr;
if (t2->type != V_ASN1_INTEGER)
goto decerr;
privkey = t2->value.integer;
} else {
const unsigned char *q = p;
if (!(privkey=d2i_ASN1_INTEGER(NULL, &p, pklen)))
goto decerr;
if (privkey->type == V_ASN1_NEG_INTEGER) {
p8->broken = PKCS8_NEG_PRIVKEY;
ASN1_INTEGER_free(privkey);
if (!(privkey = d2i_ASN1_UINTEGER(NULL, &q, pklen)))
goto decerr;
}
if (ptype != V_ASN1_SEQUENCE)
goto decerr;
}
pstr = pval;
pm = pstr->data;
pmlen = pstr->length;
if (!(dsa = d2i_DSAparams(NULL, &pm, pmlen)))
goto decerr;
/* We have parameters now set private key */
if (!(dsa->priv_key = ASN1_INTEGER_to_BN(privkey, NULL))) {
DSAerr(DSA_F_DSA_PRIV_DECODE,DSA_R_BN_ERROR);
goto dsaerr;
}
/* Calculate public key */
if (!(dsa->pub_key = BN_new())) {
DSAerr(DSA_F_DSA_PRIV_DECODE, ERR_R_MALLOC_FAILURE);
goto dsaerr;
}
if (!(ctx = BN_CTX_new())) {
DSAerr(DSA_F_DSA_PRIV_DECODE, ERR_R_MALLOC_FAILURE);
goto dsaerr;
}
if (!BN_mod_exp(dsa->pub_key, dsa->g, dsa->priv_key, dsa->p, ctx)) {
DSAerr(DSA_F_DSA_PRIV_DECODE,DSA_R_BN_ERROR);
goto dsaerr;
}
EVP_PKEY_assign_DSA(pkey, dsa);
BN_CTX_free (ctx);
if (ndsa)
sk_ASN1_TYPE_pop_free(ndsa, ASN1_TYPE_free);
else
ASN1_INTEGER_free(privkey);
return 1;
decerr:
DSAerr(DSA_F_DSA_PRIV_DECODE, EVP_R_DECODE_ERROR);
dsaerr:
BN_CTX_free (ctx);
if (privkey)
ASN1_INTEGER_free(privkey);
sk_ASN1_TYPE_pop_free(ndsa, ASN1_TYPE_free);
DSA_free(dsa);
return 0;
}
static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig,
DSA *dsa)
{
BN_CTX *ctx;
BIGNUM u1,u2,t1;
BN_MONT_CTX *mont=NULL;
int ret = -1;
if (!dsa->p || !dsa->q || !dsa->g)
{
DSAerr(DSA_F_DSA_DO_VERIFY,DSA_R_MISSING_PARAMETERS);
return -1;
}
BN_init(&u1);
BN_init(&u2);
BN_init(&t1);
if ((ctx=BN_CTX_new()) == NULL) goto err;
if (BN_is_zero(sig->r) || BN_is_negative(sig->r) ||
BN_ucmp(sig->r, dsa->q) >= 0)
{
ret = 0;
goto err;
}
if (BN_is_zero(sig->s) || BN_is_negative(sig->s) ||
BN_ucmp(sig->s, dsa->q) >= 0)
{
ret = 0;
goto err;
}
/* Calculate W = inv(S) mod Q
* save W in u2 */
if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err;
/* save M in u1 */
if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err;
/* u1 = M * w mod q */
if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err;
/* u2 = r * w mod q */
if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err;
if (dsa->flags & DSA_FLAG_CACHE_MONT_P)
{
mont = BN_MONT_CTX_set_locked(&dsa->method_mont_p,
CRYPTO_LOCK_DSA, dsa->p, ctx);
if (!mont)
goto err;
}
DSA_MOD_EXP(goto err, dsa, &t1, dsa->g, &u1, dsa->pub_key, &u2, dsa->p, ctx, mont);
/* BN_copy(&u1,&t1); */
/* let u1 = u1 mod q */
if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err;
/* V is now in u1. If the signature is correct, it will be
* equal to R. */
ret=(BN_ucmp(&u1, sig->r) == 0);
err:
/* XXX: surely this is wrong - if ret is 0, it just didn't verify;
there is no error in BN. Test should be ret == -1 (Ben) */
if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB);
if (ctx != NULL) BN_CTX_free(ctx);
BN_free(&u1);
BN_free(&u2);
BN_free(&t1);
return(ret);
}
static int dsa_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
{
const unsigned char *p, *pm;
int pklen, pmlen;
int ptype;
void *pval;
ASN1_STRING *pstr;
X509_ALGOR *palg;
ASN1_INTEGER *public_key = NULL;
DSA *dsa = NULL;
if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
return 0;
X509_ALGOR_get0(NULL, &ptype, &pval, palg);
if (ptype == V_ASN1_SEQUENCE)
{
pstr = pval;
pm = pstr->data;
pmlen = pstr->length;
if (!(dsa = d2i_DSAparams(NULL, &pm, pmlen)))
{
DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_DECODE_ERROR);
goto err;
}
}
else if ((ptype == V_ASN1_NULL) || (ptype == V_ASN1_UNDEF))
{
if (!(dsa = DSA_new()))
{
DSAerr(DSA_F_DSA_PUB_DECODE, ERR_R_MALLOC_FAILURE);
goto err;
}
}
else
{
DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_PARAMETER_ENCODING_ERROR);
goto err;
}
if (!(public_key=d2i_ASN1_INTEGER(NULL, &p, pklen)))
{
DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_DECODE_ERROR);
goto err;
}
if (!(dsa->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)))
{
DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_BN_DECODE_ERROR);
goto err;
}
ASN1_INTEGER_free(public_key);
EVP_PKEY_assign_DSA(pkey, dsa);
return 1;
err:
if (public_key)
ASN1_INTEGER_free(public_key);
if (dsa)
DSA_free(dsa);
return 0;
}
static DSA_SIG *dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
{
BIGNUM *kinv=NULL,*r=NULL,*s=NULL;
BIGNUM m;
BIGNUM xr;
BN_CTX *ctx=NULL;
int i,reason=ERR_R_BN_LIB;
DSA_SIG *ret=NULL;
BN_init(&m);
BN_init(&xr);
if (!dsa->p || !dsa->q || !dsa->g)
{
reason=DSA_R_MISSING_PARAMETERS;
goto err;
}
s=BN_new();
if (s == NULL) goto err;
i=BN_num_bytes(dsa->q); /* should be 20 */
if ((dlen > i) || (dlen > 50))
{
reason=DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE;
goto err;
}
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
if ((dsa->kinv == NULL) || (dsa->r == NULL))
{
if (!DSA_sign_setup(dsa,ctx,&kinv,&r)) goto err;
}
else
{
kinv=dsa->kinv;
dsa->kinv=NULL;
r=dsa->r;
dsa->r=NULL;
}
if (BN_bin2bn(dgst,dlen,&m) == NULL) goto err;
/* Compute s = inv(k) (m + xr) mod q */
if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */
if (!BN_add(s, &xr, &m)) goto err; /* s = m + xr */
if (BN_cmp(s,dsa->q) > 0)
BN_sub(s,s,dsa->q);
if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err;
ret=DSA_SIG_new();
if (ret == NULL) goto err;
ret->r = r;
ret->s = s;
err:
if (!ret)
{
DSAerr(DSA_F_DSA_DO_SIGN,reason);
BN_free(r);
BN_free(s);
}
if (ctx != NULL) BN_CTX_free(ctx);
BN_clear_free(&m);
BN_clear_free(&xr);
if (kinv != NULL) /* dsa->kinv is NULL now if we used it */
BN_clear_free(kinv);
return(ret);
}
static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
{
BN_CTX *ctx;
BIGNUM k,kq,*K,*kinv=NULL,*r=NULL;
int ret=0;
if (!dsa->p || !dsa->q || !dsa->g)
{
DSAerr(DSA_F_DSA_SIGN_SETUP,DSA_R_MISSING_PARAMETERS);
return 0;
}
BN_init(&k);
BN_init(&kq);
if (ctx_in == NULL)
{
if ((ctx=BN_CTX_new()) == NULL) goto err;
}
else
ctx=ctx_in;
if ((r=BN_new()) == NULL) goto err;
/* Get random k */
do
if (!BN_rand_range(&k, dsa->q)) goto err;
while (BN_is_zero(&k));
if ((dsa->flags & DSA_FLAG_NO_EXP_CONSTTIME) == 0)
{
BN_set_flags(&k, BN_FLG_EXP_CONSTTIME);
}
if (dsa->flags & DSA_FLAG_CACHE_MONT_P)
{
if (!BN_MONT_CTX_set_locked(&dsa->method_mont_p,
CRYPTO_LOCK_DSA,
dsa->p, ctx))
goto err;
}
/* Compute r = (g^k mod p) mod q */
if ((dsa->flags & DSA_FLAG_NO_EXP_CONSTTIME) == 0)
{
if (!BN_copy(&kq, &k)) goto err;
/* We do not want timing information to leak the length of k,
* so we compute g^k using an equivalent exponent of fixed length.
*
* (This is a kludge that we need because the BN_mod_exp_mont()
* does not let us specify the desired timing behaviour.) */
if (!BN_add(&kq, &kq, dsa->q)) goto err;
if (BN_num_bits(&kq) <= BN_num_bits(dsa->q))
{
if (!BN_add(&kq, &kq, dsa->q)) goto err;
}
K = &kq;
}
else
{
K = &k;
}
DSA_BN_MOD_EXP(goto err, dsa, r, dsa->g, K, dsa->p, ctx,
dsa->method_mont_p);
if (!BN_mod(r,r,dsa->q,ctx)) goto err;
/* Compute part of 's = inv(k) (m + xr) mod q' */
if ((kinv=BN_mod_inverse(NULL,&k,dsa->q,ctx)) == NULL) goto err;
if (*kinvp != NULL) BN_clear_free(*kinvp);
*kinvp=kinv;
kinv=NULL;
if (*rp != NULL) BN_clear_free(*rp);
*rp=r;
ret=1;
err:
if (!ret)
{
DSAerr(DSA_F_DSA_SIGN_SETUP,ERR_R_BN_LIB);
if (kinv != NULL) BN_clear_free(kinv);
if (r != NULL) BN_clear_free(r);
}
if (ctx_in == NULL) BN_CTX_free(ctx);
if (kinv != NULL) BN_clear_free(kinv);
BN_clear_free(&k);
BN_clear_free(&kq);
return(ret);
}
static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig,
DSA *dsa)
{
BN_CTX *ctx;
BIGNUM u1,u2,t1;
BN_MONT_CTX *mont=NULL;
int ret = -1;
if ((ctx=BN_CTX_new()) == NULL) goto err;
BN_init(&u1);
BN_init(&u2);
BN_init(&t1);
if (BN_is_zero(sig->r) || sig->r->neg || BN_ucmp(sig->r, dsa->q) >= 0)
{
ret = 0;
goto err;
}
if (BN_is_zero(sig->s) || sig->s->neg || BN_ucmp(sig->s, dsa->q) >= 0)
{
ret = 0;
goto err;
}
/* Calculate W = inv(S) mod Q
* save W in u2 */
if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err;
/* save M in u1 */
if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err;
/* u1 = M * w mod q */
if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err;
/* u2 = r * w mod q */
if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err;
if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P))
{
if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p,
dsa->p,ctx)) goto err;
}
mont=(BN_MONT_CTX *)dsa->method_mont_p;
#if 0
{
BIGNUM t2;
BN_init(&t2);
/* v = ( g^u1 * y^u2 mod p ) mod q */
/* let t1 = g ^ u1 mod p */
if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err;
/* let t2 = y ^ u2 mod p */
if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err;
/* let u1 = t1 * t2 mod p */
if (!BN_mod_mul(&u1,&t1,&t2,dsa->p,ctx)) goto err_bn;
BN_free(&t2);
}
/* let u1 = u1 mod q */
if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err;
#else
{
if (!dsa->meth->dsa_mod_exp(dsa, &t1,dsa->g,&u1,dsa->pub_key,&u2,
dsa->p,ctx,mont)) goto err;
/* BN_copy(&u1,&t1); */
/* let u1 = u1 mod q */
if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err;
}
#endif
/* V is now in u1. If the signature is correct, it will be
* equal to R. */
ret=(BN_ucmp(&u1, sig->r) == 0);
err:
if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB);
if (ctx != NULL) BN_CTX_free(ctx);
BN_free(&u1);
BN_free(&u2);
BN_free(&t1);
return(ret);
}
static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig,
DSA *dsa)
{
BN_CTX *ctx;
BIGNUM u1,u2,t1;
BN_MONT_CTX *mont=NULL;
int ret = -1;
if (!dsa->p || !dsa->q || !dsa->g)
{
DSAerr(DSA_F_DSA_DO_VERIFY,DSA_R_MISSING_PARAMETERS);
return -1;
}
if (BN_num_bits(dsa->q) != 160)
{
DSAerr(DSA_F_DSA_DO_VERIFY,DSA_R_BAD_Q_VALUE);
return -1;
}
if (BN_num_bits(dsa->p) > OPENSSL_DSA_MAX_MODULUS_BITS)
{
DSAerr(DSA_F_DSA_DO_VERIFY,DSA_R_MODULUS_TOO_LARGE);
return -1;
}
BN_init(&u1);
BN_init(&u2);
BN_init(&t1);
if ((ctx=BN_CTX_new()) == NULL) goto err;
if (BN_is_zero(sig->r) || sig->r->neg || BN_ucmp(sig->r, dsa->q) >= 0)
{
ret = 0;
goto err;
}
if (BN_is_zero(sig->s) || sig->s->neg || BN_ucmp(sig->s, dsa->q) >= 0)
{
ret = 0;
goto err;
}
/* Calculate W = inv(S) mod Q
* save W in u2 */
if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err;
/* save M in u1 */
if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err;
/* u1 = M * w mod q */
if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err;
/* u2 = r * w mod q */
if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err;
if (dsa->flags & DSA_FLAG_CACHE_MONT_P)
{
mont = BN_MONT_CTX_set_locked(
(BN_MONT_CTX **)&dsa->method_mont_p,
CRYPTO_LOCK_DSA, dsa->p, ctx);
if (!mont)
goto err;
}
#if 0
{
BIGNUM t2;
BN_init(&t2);
/* v = ( g^u1 * y^u2 mod p ) mod q */
/* let t1 = g ^ u1 mod p */
if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err;
/* let t2 = y ^ u2 mod p */
if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err;
/* let u1 = t1 * t2 mod p */
if (!BN_mod_mul(&u1,&t1,&t2,dsa->p,ctx)) goto err_bn;
BN_free(&t2);
}
/* let u1 = u1 mod q */
if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err;
#else
{
if (!dsa->meth->dsa_mod_exp(dsa, &t1,dsa->g,&u1,dsa->pub_key,&u2,
dsa->p,ctx,mont)) goto err;
/* BN_copy(&u1,&t1); */
/* let u1 = u1 mod q */
if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err;
}
#endif
/* V is now in u1. If the signature is correct, it will be
* equal to R. */
ret=(BN_ucmp(&u1, sig->r) == 0);
err:
if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB);
if (ctx != NULL) BN_CTX_free(ctx);
BN_free(&u1);
BN_free(&u2);
BN_free(&t1);
return(ret);
}
static int do_dsa_print(BIO *bp, const DSA *x, int off, int ptype)
{
unsigned char *m = NULL;
int ret = 0;
size_t buf_len = 0;
const char *ktype = NULL;
const BIGNUM *priv_key, *pub_key;
if (ptype == 2)
priv_key = x->priv_key;
else
priv_key = NULL;
if (ptype > 0)
pub_key = x->pub_key;
else
pub_key = NULL;
if (ptype == 2)
ktype = "Private-Key";
else if (ptype == 1)
ktype = "Public-Key";
else
ktype = "DSA-Parameters";
update_buflen(x->p, &buf_len);
update_buflen(x->q, &buf_len);
update_buflen(x->g, &buf_len);
update_buflen(priv_key, &buf_len);
update_buflen(pub_key, &buf_len);
m = (unsigned char *)OPENSSL_malloc(buf_len + 10);
if (m == NULL) {
DSAerr(DSA_F_DO_DSA_PRINT, ERR_R_MALLOC_FAILURE);
goto err;
}
if (priv_key) {
if (!BIO_indent(bp, off, 128))
goto err;
if (BIO_printf(bp, "%s: (%d bit)\n", ktype, BN_num_bits(x->p))
<= 0)
goto err;
}
if (!ASN1_bn_print(bp, "priv:", priv_key, m, off))
goto err;
if (!ASN1_bn_print(bp, "pub: ", pub_key, m, off))
goto err;
if (!ASN1_bn_print(bp, "P: ", x->p, m, off))
goto err;
if (!ASN1_bn_print(bp, "Q: ", x->q, m, off))
goto err;
if (!ASN1_bn_print(bp, "G: ", x->g, m, off))
goto err;
ret = 1;
err:
if (m != NULL)
OPENSSL_free(m);
return (ret);
}
int dsa_builtin_paramgen2(DSA *ret, size_t L, size_t N,
const EVP_MD *evpmd, const unsigned char *seed_in, size_t seed_len,
unsigned char *seed_out,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
{
int ok=-1;
unsigned char *seed = NULL;
unsigned char md[EVP_MAX_MD_SIZE];
int mdsize;
BIGNUM *r0,*W,*X,*c,*test;
BIGNUM *g=NULL,*q=NULL,*p=NULL;
BN_MONT_CTX *mont=NULL;
int i, k, n=0, m=0, qsize = N >> 3;
int counter=0;
int r=0;
BN_CTX *ctx=NULL;
unsigned int h=2;
#ifdef OPENSSL_FIPS
if(FIPS_selftest_failed())
{
FIPSerr(FIPS_F_DSA_BUILTIN_PARAMGEN2,
FIPS_R_FIPS_SELFTEST_FAILED);
goto err;
}
if (!fips_check_dsa_prng(ret, L, N))
goto err;
#endif
if (evpmd == NULL)
{
if (N == 160)
evpmd = EVP_sha1();
else if (N == 224)
evpmd = EVP_sha224();
else
evpmd = EVP_sha256();
}
mdsize = M_EVP_MD_size(evpmd);
if (seed_len == 0)
seed_len = mdsize;
seed = OPENSSL_malloc(seed_len);
if (!seed)
goto err;
if (seed_in)
memcpy(seed, seed_in, seed_len);
if ((ctx=BN_CTX_new()) == NULL)
goto err;
if ((mont=BN_MONT_CTX_new()) == NULL)
goto err;
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
g = BN_CTX_get(ctx);
W = BN_CTX_get(ctx);
q = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
c = BN_CTX_get(ctx);
p = BN_CTX_get(ctx);
test = BN_CTX_get(ctx);
if (!BN_lshift(test,BN_value_one(),L-1))
goto err;
for (;;)
{
for (;;) /* find q */
{
unsigned char *pmd;
/* step 1 */
if(!BN_GENCB_call(cb, 0, m++))
goto err;
if (!seed_in)
{
if (RAND_pseudo_bytes(seed, seed_len) < 0)
goto err;
}
/* step 2 */
if (!EVP_Digest(seed, seed_len, md, NULL, evpmd, NULL))
goto err;
/* Take least significant bits of md */
if (mdsize > qsize)
pmd = md + mdsize - qsize;
else
pmd = md;
if (mdsize < qsize)
memset(md + mdsize, 0, qsize - mdsize);
/* step 3 */
pmd[0] |= 0x80;
pmd[qsize-1] |= 0x01;
if (!BN_bin2bn(pmd, qsize, q))
goto err;
/* step 4 */
r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
seed_in ? 1 : 0, cb);
if (r > 0)
break;
if (r != 0)
goto err;
/* Provided seed didn't produce a prime: error */
if (seed_in)
{
ok = 0;
DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_Q_NOT_PRIME);
goto err;
}
/* do a callback call */
/* step 5 */
}
/* Copy seed to seed_out before we mess with it */
if (seed_out)
memcpy(seed_out, seed, seed_len);
if(!BN_GENCB_call(cb, 2, 0)) goto err;
if(!BN_GENCB_call(cb, 3, 0)) goto err;
/* step 6 */
counter=0;
/* "offset = 1" */
n=(L-1)/(mdsize << 3);
for (;;)
{
if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
goto err;
/* step 7 */
BN_zero(W);
/* now 'buf' contains "SEED + offset - 1" */
for (k=0; k<=n; k++)
{
/* obtain "SEED + offset + k" by incrementing: */
for (i = seed_len-1; i >= 0; i--)
{
seed[i]++;
if (seed[i] != 0)
break;
}
if (!EVP_Digest(seed, seed_len, md ,NULL, evpmd,
NULL))
goto err;
/* step 8 */
if (!BN_bin2bn(md, mdsize, r0))
goto err;
if (!BN_lshift(r0,r0,(mdsize << 3)*k)) goto err;
if (!BN_add(W,W,r0)) goto err;
}
/* more of step 8 */
if (!BN_mask_bits(W,L-1)) goto err;
if (!BN_copy(X,W)) goto err;
if (!BN_add(X,X,test)) goto err;
/* step 9 */
if (!BN_lshift1(r0,q)) goto err;
if (!BN_mod(c,X,r0,ctx)) goto err;
if (!BN_sub(r0,c,BN_value_one())) goto err;
if (!BN_sub(p,X,r0)) goto err;
/* step 10 */
if (BN_cmp(p,test) >= 0)
{
/* step 11 */
r = BN_is_prime_fasttest_ex(p, DSS_prime_checks,
ctx, 1, cb);
if (r > 0)
goto end; /* found it */
if (r != 0)
goto err;
}
/* step 13 */
counter++;
/* "offset = offset + n + 1" */
/* step 14 */
if (counter >= 4096) break;
}
}
end:
if(!BN_GENCB_call(cb, 2, 1))
goto err;
/* We now need to generate g */
/* Set r0=(p-1)/q */
if (!BN_sub(test,p,BN_value_one())) goto err;
if (!BN_div(r0,NULL,test,q,ctx)) goto err;
if (!BN_set_word(test,h)) goto err;
if (!BN_MONT_CTX_set(mont,p,ctx)) goto err;
for (;;)
{
/* g=test^r0%p */
if (!BN_mod_exp_mont(g,test,r0,p,ctx,mont)) goto err;
if (!BN_is_one(g)) break;
if (!BN_add(test,test,BN_value_one())) goto err;
h++;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
ok=1;
err:
if (ok == 1)
{
if(ret->p) BN_free(ret->p);
if(ret->q) BN_free(ret->q);
if(ret->g) BN_free(ret->g);
ret->p=BN_dup(p);
ret->q=BN_dup(q);
ret->g=BN_dup(g);
if (ret->p == NULL || ret->q == NULL || ret->g == NULL)
{
ok=-1;
goto err;
}
if (counter_ret != NULL) *counter_ret=counter;
if (h_ret != NULL) *h_ret=h;
}
if (seed)
OPENSSL_free(seed);
if(ctx)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
if (mont != NULL) BN_MONT_CTX_free(mont);
return ok;
}
int dsa_builtin_paramgen(DSA *ret, size_t bits, size_t qbits,
const EVP_MD *evpmd, const unsigned char *seed_in, size_t seed_len,
unsigned char *seed_out,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
{
int ok=0;
unsigned char seed[SHA256_DIGEST_LENGTH];
unsigned char md[SHA256_DIGEST_LENGTH];
unsigned char buf[SHA256_DIGEST_LENGTH],buf2[SHA256_DIGEST_LENGTH];
BIGNUM *r0,*W,*X,*c,*test;
BIGNUM *g=NULL,*q=NULL,*p=NULL;
BN_MONT_CTX *mont=NULL;
int i, k, n=0, m=0, qsize = qbits >> 3;
int counter=0;
int r=0;
BN_CTX *ctx=NULL;
unsigned int h=2;
#ifdef OPENSSL_FIPS
if(FIPS_selftest_failed())
{
FIPSerr(FIPS_F_DSA_BUILTIN_PARAMGEN, FIPS_R_FIPS_SELFTEST_FAILED);
goto err;
}
if (FIPS_mode() && !(ret->flags & DSA_FLAG_NON_FIPS_ALLOW)
&& (bits < OPENSSL_DSA_FIPS_MIN_MODULUS_BITS))
{
DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN, DSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
#endif
if (qsize != SHA_DIGEST_LENGTH && qsize != SHA224_DIGEST_LENGTH &&
qsize != SHA256_DIGEST_LENGTH)
/* invalid q size */
return 0;
if (evpmd == NULL)
/* use SHA1 as default */
evpmd = EVP_sha1();
if (bits < 512)
bits = 512;
bits = (bits+63)/64*64;
/* NB: seed_len == 0 is special case: copy generated seed to
* seed_in if it is not NULL.
*/
if (seed_len && (seed_len < (size_t)qsize))
seed_in = NULL; /* seed buffer too small -- ignore */
if (seed_len > (size_t)qsize)
seed_len = qsize; /* App. 2.2 of FIPS PUB 186 allows larger SEED,
* but our internal buffers are restricted to 160 bits*/
if (seed_in != NULL)
memcpy(seed, seed_in, seed_len);
if ((ctx=BN_CTX_new()) == NULL)
goto err;
if ((mont=BN_MONT_CTX_new()) == NULL)
goto err;
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
g = BN_CTX_get(ctx);
W = BN_CTX_get(ctx);
q = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
c = BN_CTX_get(ctx);
p = BN_CTX_get(ctx);
test = BN_CTX_get(ctx);
if (!BN_lshift(test,BN_value_one(),bits-1))
goto err;
for (;;)
{
for (;;) /* find q */
{
int seed_is_random;
/* step 1 */
if(!BN_GENCB_call(cb, 0, m++))
goto err;
if (!seed_len)
{
if (RAND_pseudo_bytes(seed, qsize) < 0)
goto err;
seed_is_random = 1;
}
else
{
seed_is_random = 0;
seed_len=0; /* use random seed if 'seed_in' turns out to be bad*/
}
memcpy(buf , seed, qsize);
memcpy(buf2, seed, qsize);
/* precompute "SEED + 1" for step 7: */
for (i = qsize-1; i >= 0; i--)
{
buf[i]++;
if (buf[i] != 0)
break;
}
/* step 2 */
if (!EVP_Digest(seed, qsize, md, NULL, evpmd, NULL))
goto err;
if (!EVP_Digest(buf, qsize, buf2, NULL, evpmd, NULL))
goto err;
for (i = 0; i < qsize; i++)
md[i]^=buf2[i];
/* step 3 */
md[0] |= 0x80;
md[qsize-1] |= 0x01;
if (!BN_bin2bn(md, qsize, q))
goto err;
/* step 4 */
r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
seed_is_random, cb);
if (r > 0)
break;
if (r != 0)
goto err;
/* do a callback call */
/* step 5 */
}
if(!BN_GENCB_call(cb, 2, 0)) goto err;
if(!BN_GENCB_call(cb, 3, 0)) goto err;
/* step 6 */
counter=0;
/* "offset = 2" */
n=(bits-1)/160;
for (;;)
{
if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
goto err;
/* step 7 */
BN_zero(W);
/* now 'buf' contains "SEED + offset - 1" */
for (k=0; k<=n; k++)
{
/* obtain "SEED + offset + k" by incrementing: */
for (i = qsize-1; i >= 0; i--)
{
buf[i]++;
if (buf[i] != 0)
break;
}
if (!EVP_Digest(buf, qsize, md ,NULL, evpmd,
NULL))
goto err;
/* step 8 */
if (!BN_bin2bn(md, qsize, r0))
goto err;
if (!BN_lshift(r0,r0,(qsize << 3)*k)) goto err;
if (!BN_add(W,W,r0)) goto err;
}
/* more of step 8 */
if (!BN_mask_bits(W,bits-1)) goto err;
if (!BN_copy(X,W)) goto err;
if (!BN_add(X,X,test)) goto err;
/* step 9 */
if (!BN_lshift1(r0,q)) goto err;
if (!BN_mod(c,X,r0,ctx)) goto err;
if (!BN_sub(r0,c,BN_value_one())) goto err;
if (!BN_sub(p,X,r0)) goto err;
/* step 10 */
if (BN_cmp(p,test) >= 0)
{
/* step 11 */
r = BN_is_prime_fasttest_ex(p, DSS_prime_checks,
ctx, 1, cb);
if (r > 0)
goto end; /* found it */
if (r != 0)
goto err;
}
/* step 13 */
counter++;
/* "offset = offset + n + 1" */
/* step 14 */
if (counter >= 4096) break;
}
}
end:
if(!BN_GENCB_call(cb, 2, 1))
goto err;
/* We now need to generate g */
/* Set r0=(p-1)/q */
if (!BN_sub(test,p,BN_value_one())) goto err;
if (!BN_div(r0,NULL,test,q,ctx)) goto err;
if (!BN_set_word(test,h)) goto err;
if (!BN_MONT_CTX_set(mont,p,ctx)) goto err;
for (;;)
{
/* g=test^r0%p */
if (!BN_mod_exp_mont(g,test,r0,p,ctx,mont)) goto err;
if (!BN_is_one(g)) break;
if (!BN_add(test,test,BN_value_one())) goto err;
h++;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
ok=1;
err:
if (ok)
{
if(ret->p) BN_free(ret->p);
if(ret->q) BN_free(ret->q);
if(ret->g) BN_free(ret->g);
ret->p=BN_dup(p);
ret->q=BN_dup(q);
ret->g=BN_dup(g);
if (ret->p == NULL || ret->q == NULL || ret->g == NULL)
{
ok=0;
goto err;
}
if (counter_ret != NULL) *counter_ret=counter;
if (h_ret != NULL) *h_ret=h;
if (seed_out)
memcpy(seed_out, seed, qsize);
}
if(ctx)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
if (mont != NULL) BN_MONT_CTX_free(mont);
return ok;
}
static DSA_SIG *dsa_do_sign(const unsigned char *dgst, FIPS_DSA_SIZE_T dlen, DSA *dsa)
{
BIGNUM *kinv=NULL,*r=NULL,*s=NULL;
BIGNUM m;
BIGNUM xr;
BN_CTX *ctx=NULL;
int i,reason=ERR_R_BN_LIB;
DSA_SIG *ret=NULL;
if(FIPS_selftest_failed())
{
FIPSerr(FIPS_F_DSA_DO_SIGN,FIPS_R_FIPS_SELFTEST_FAILED);
return NULL;
}
if (FIPS_mode() && (BN_num_bits(dsa->p) < OPENSSL_DSA_FIPS_MIN_MODULUS_BITS))
{
DSAerr(DSA_F_DSA_DO_SIGN, DSA_R_KEY_SIZE_TOO_SMALL);
return NULL;
}
BN_init(&m);
BN_init(&xr);
if (!dsa->p || !dsa->q || !dsa->g)
{
reason=DSA_R_MISSING_PARAMETERS;
goto err;
}
s=BN_new();
if (s == NULL) goto err;
i=BN_num_bytes(dsa->q); /* should be 20 */
if ((dlen > i) || (dlen > 50))
{
reason=DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE;
goto err;
}
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
if (!dsa->meth->dsa_sign_setup(dsa,ctx,&kinv,&r)) goto err;
if (BN_bin2bn(dgst,dlen,&m) == NULL) goto err;
/* Compute s = inv(k) (m + xr) mod q */
if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */
if (!BN_add(s, &xr, &m)) goto err; /* s = m + xr */
if (BN_cmp(s,dsa->q) > 0)
BN_sub(s,s,dsa->q);
if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err;
ret= DSA_SIG_new();
if (ret == NULL) goto err;
ret->r = r;
ret->s = s;
err:
if (!ret)
{
DSAerr(DSA_F_DSA_DO_SIGN,reason);
BN_free(r);
BN_free(s);
}
if (ctx != NULL) BN_CTX_free(ctx);
BN_clear_free(&m);
BN_clear_free(&xr);
if (kinv != NULL) /* dsa->kinv is NULL now if we used it */
BN_clear_free(kinv);
return(ret);
}
static int dsa_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
{
const unsigned char *p, *pm;
int pklen, pmlen;
int ptype;
void *pval;
ASN1_STRING *pstr;
X509_ALGOR *palg;
ASN1_INTEGER *privkey = NULL;
BN_CTX *ctx = NULL;
DSA *dsa = NULL;
int ret = 0;
if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
return 0;
X509_ALGOR_get0(NULL, &ptype, &pval, palg);
if ((privkey = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL)
goto decerr;
if (privkey->type == V_ASN1_NEG_INTEGER || ptype != V_ASN1_SEQUENCE)
goto decerr;
pstr = pval;
pm = pstr->data;
pmlen = pstr->length;
if ((dsa = d2i_DSAparams(NULL, &pm, pmlen)) == NULL)
goto decerr;
/* We have parameters now set private key */
if ((dsa->priv_key = BN_secure_new()) == NULL
|| !ASN1_INTEGER_to_BN(privkey, dsa->priv_key)) {
DSAerr(DSA_F_DSA_PRIV_DECODE, DSA_R_BN_ERROR);
goto dsaerr;
}
/* Calculate public key */
if ((dsa->pub_key = BN_new()) == NULL) {
DSAerr(DSA_F_DSA_PRIV_DECODE, ERR_R_MALLOC_FAILURE);
goto dsaerr;
}
if ((ctx = BN_CTX_new()) == NULL) {
DSAerr(DSA_F_DSA_PRIV_DECODE, ERR_R_MALLOC_FAILURE);
goto dsaerr;
}
if (!BN_mod_exp(dsa->pub_key, dsa->g, dsa->priv_key, dsa->p, ctx)) {
DSAerr(DSA_F_DSA_PRIV_DECODE, DSA_R_BN_ERROR);
goto dsaerr;
}
EVP_PKEY_assign_DSA(pkey, dsa);
ret = 1;
goto done;
decerr:
DSAerr(DSA_F_DSA_PRIV_DECODE, DSA_R_DECODE_ERROR);
dsaerr:
DSA_free(dsa);
done:
BN_CTX_free(ctx);
ASN1_STRING_clear_free(privkey);
return ret;
}
