Exemplo n.º 1
0
int PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt,
                       int saltlen, int id, int iter, int n,
                       unsigned char *out, const EVP_MD *md_type)
{
    unsigned char *B = NULL, *D = NULL, *I = NULL, *p = NULL, *Ai = NULL;
    int Slen, Plen, Ilen, Ijlen;
    int i, j, u, v;
    int ret = 0;
    BIGNUM *Ij = NULL, *Bpl1 = NULL; /* These hold Ij and B + 1 */
    EVP_MD_CTX *ctx = NULL;
#ifdef  OPENSSL_DEBUG_KEYGEN
    unsigned char *tmpout = out;
    int tmpn = n;
#endif

    ctx = EVP_MD_CTX_new();
    if (ctx == NULL)
        goto err;

#ifdef  OPENSSL_DEBUG_KEYGEN
    fprintf(stderr, "KEYGEN DEBUG\n");
    fprintf(stderr, "ID %d, ITER %d\n", id, iter);
    fprintf(stderr, "Password (length %d):\n", passlen);
    h__dump(pass, passlen);
    fprintf(stderr, "Salt (length %d):\n", saltlen);
    h__dump(salt, saltlen);
#endif
    v = EVP_MD_block_size(md_type);
    u = EVP_MD_size(md_type);
    if (u < 0 || v <= 0)
        goto err;
    D = OPENSSL_malloc(v);
    Ai = OPENSSL_malloc(u);
    B = OPENSSL_malloc(v + 1);
    Slen = v * ((saltlen + v - 1) / v);
    if (passlen)
        Plen = v * ((passlen + v - 1) / v);
    else
        Plen = 0;
    Ilen = Slen + Plen;
    I = OPENSSL_malloc(Ilen);
    Ij = BN_new();
    Bpl1 = BN_new();
    if (D == NULL || Ai == NULL || B == NULL || I == NULL || Ij == NULL
            || Bpl1 == NULL)
        goto err;
    for (i = 0; i < v; i++)
        D[i] = id;
    p = I;
    for (i = 0; i < Slen; i++)
        *p++ = salt[i % saltlen];
    for (i = 0; i < Plen; i++)
        *p++ = pass[i % passlen];
    for (;;) {
        if (!EVP_DigestInit_ex(ctx, md_type, NULL)
            || !EVP_DigestUpdate(ctx, D, v)
            || !EVP_DigestUpdate(ctx, I, Ilen)
            || !EVP_DigestFinal_ex(ctx, Ai, NULL))
            goto err;
        for (j = 1; j < iter; j++) {
            if (!EVP_DigestInit_ex(ctx, md_type, NULL)
                || !EVP_DigestUpdate(ctx, Ai, u)
                || !EVP_DigestFinal_ex(ctx, Ai, NULL))
                goto err;
        }
        memcpy(out, Ai, min(n, u));
        if (u >= n) {
#ifdef OPENSSL_DEBUG_KEYGEN
            fprintf(stderr, "Output KEY (length %d)\n", tmpn);
            h__dump(tmpout, tmpn);
#endif
            ret = 1;
            goto end;
        }
        n -= u;
        out += u;
        for (j = 0; j < v; j++)
            B[j] = Ai[j % u];
        /* Work out B + 1 first then can use B as tmp space */
        if (!BN_bin2bn(B, v, Bpl1))
            goto err;
        if (!BN_add_word(Bpl1, 1))
            goto err;
        for (j = 0; j < Ilen; j += v) {
            if (!BN_bin2bn(I + j, v, Ij))
                goto err;
            if (!BN_add(Ij, Ij, Bpl1))
                goto err;
            if (!BN_bn2bin(Ij, B))
                goto err;
            Ijlen = BN_num_bytes(Ij);
            /* If more than 2^(v*8) - 1 cut off MSB */
            if (Ijlen > v) {
                if (!BN_bn2bin(Ij, B))
                    goto err;
                memcpy(I + j, B + 1, v);
#ifndef PKCS12_BROKEN_KEYGEN
                /* If less than v bytes pad with zeroes */
            } else if (Ijlen < v) {
                memset(I + j, 0, v - Ijlen);
                if (!BN_bn2bin(Ij, I + j + v - Ijlen))
                    goto err;
#endif
            } else if (!BN_bn2bin(Ij, I + j))
                goto err;
        }
    }

 err:
    PKCS12err(PKCS12_F_PKCS12_KEY_GEN_UNI, ERR_R_MALLOC_FAILURE);

 end:
    OPENSSL_free(Ai);
    OPENSSL_free(B);
    OPENSSL_free(D);
    OPENSSL_free(I);
    BN_free(Ij);
    BN_free(Bpl1);
    EVP_MD_CTX_free(ctx);
    return ret;
}
Exemplo n.º 2
0
int BN_X931_derive_prime_ex(BIGNUM *p, BIGNUM *p1, BIGNUM *p2,
                            const BIGNUM *Xp, const BIGNUM *Xp1,
                            const BIGNUM *Xp2, const BIGNUM *e, BN_CTX *ctx,
                            BN_GENCB *cb)
{
    int ret = 0;

    BIGNUM *t, *p1p2, *pm1;

    /* Only even e supported */
    if (!BN_is_odd(e))
        return 0;

    BN_CTX_start(ctx);
    if (!p1)
        p1 = BN_CTX_get(ctx);

    if (!p2)
        p2 = BN_CTX_get(ctx);

    t = BN_CTX_get(ctx);

    p1p2 = BN_CTX_get(ctx);

    pm1 = BN_CTX_get(ctx);

    if (!bn_x931_derive_pi(p1, Xp1, ctx, cb))
        goto err;

    if (!bn_x931_derive_pi(p2, Xp2, ctx, cb))
        goto err;

    if (!BN_mul(p1p2, p1, p2, ctx))
        goto err;

    /* First set p to value of Rp */

    if (!BN_mod_inverse(p, p2, p1, ctx))
        goto err;

    if (!BN_mul(p, p, p2, ctx))
        goto err;

    if (!BN_mod_inverse(t, p1, p2, ctx))
        goto err;

    if (!BN_mul(t, t, p1, ctx))
        goto err;

    if (!BN_sub(p, p, t))
        goto err;

    if (p->neg && !BN_add(p, p, p1p2))
        goto err;

    /* p now equals Rp */

    if (!BN_mod_sub(p, p, Xp, p1p2, ctx))
        goto err;

    if (!BN_add(p, p, Xp))
        goto err;

    /* p now equals Yp0 */

    for (;;) {
        int i = 1;
        BN_GENCB_call(cb, 0, i++);
        if (!BN_copy(pm1, p))
            goto err;
        if (!BN_sub_word(pm1, 1))
            goto err;
        if (!BN_gcd(t, pm1, e, ctx))
            goto err;
        if (BN_is_one(t)
            /*
             * X9.31 specifies 8 MR and 1 Lucas test or any prime test
             * offering similar or better guarantees 50 MR is considerably
             * better.
             */
            && BN_is_prime_fasttest_ex(p, 50, ctx, 1, cb))
            break;
        if (!BN_add(p, p, p1p2))
            goto err;
    }

    BN_GENCB_call(cb, 3, 0);

    ret = 1;

 err:

    BN_CTX_end(ctx);

    return ret;
}
Exemplo n.º 3
0
int
PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt,
    int saltlen, int id, int iter, int n, unsigned char *out,
    const EVP_MD *md_type)
{
	unsigned char *B, *D, *I, *p, *Ai;
	int Slen, Plen, Ilen, Ijlen;
	int i, j, u, v;
	int ret = 0;
	BIGNUM *Ij, *Bpl1;	/* These hold Ij and B + 1 */
	EVP_MD_CTX ctx;

#if 0
	if (!pass) {
		PKCS12err(PKCS12_F_PKCS12_KEY_GEN_UNI, ERR_R_PASSED_NULL_PARAMETER);
		return 0;
	}
#endif

	EVP_MD_CTX_init(&ctx);
	v = EVP_MD_block_size(md_type);
	u = EVP_MD_size(md_type);
	if (u < 0)
		return 0;
	D = malloc(v);
	Ai = malloc(u);
	B = malloc(v + 1);
	Slen = v * ((saltlen + v - 1) / v);
	if (passlen)
		Plen = v * ((passlen + v - 1)/v);
	else
		Plen = 0;
	Ilen = Slen + Plen;
	I = malloc(Ilen);
	Ij = BN_new();
	Bpl1 = BN_new();
	if (!D || !Ai || !B || !I || !Ij || !Bpl1)
		goto err;
	for (i = 0; i < v; i++)
		D[i] = id;
	p = I;
	for (i = 0; i < Slen; i++)
		*p++ = salt[i % saltlen];
	for (i = 0; i < Plen; i++)
		*p++ = pass[i % passlen];
	for (;;) {
		if (!EVP_DigestInit_ex(&ctx, md_type, NULL) ||
		    !EVP_DigestUpdate(&ctx, D, v) ||
		    !EVP_DigestUpdate(&ctx, I, Ilen) ||
		    !EVP_DigestFinal_ex(&ctx, Ai, NULL))
			goto err;
		for (j = 1; j < iter; j++) {
			if (!EVP_DigestInit_ex(&ctx, md_type, NULL) ||
			    !EVP_DigestUpdate(&ctx, Ai, u) ||
			    !EVP_DigestFinal_ex(&ctx, Ai, NULL))
				goto err;
		}
		memcpy (out, Ai, min (n, u));
		if (u >= n) {
			ret = 1;
			goto end;
		}
		n -= u;
		out += u;
		for (j = 0; j < v; j++)
			B[j] = Ai[j % u];
		/* Work out B + 1 first then can use B as tmp space */
		if (!BN_bin2bn (B, v, Bpl1))
			goto err;
		if (!BN_add_word (Bpl1, 1))
			goto err;
		for (j = 0; j < Ilen; j += v) {
			if (!BN_bin2bn(I + j, v, Ij))
				goto err;
			if (!BN_add(Ij, Ij, Bpl1))
				goto err;
			if (!BN_bn2bin(Ij, B))
				goto err;
			Ijlen = BN_num_bytes (Ij);
			/* If more than 2^(v*8) - 1 cut off MSB */
			if (Ijlen > v) {
				if (!BN_bn2bin (Ij, B))
					goto err;
				memcpy (I + j, B + 1, v);
#ifndef PKCS12_BROKEN_KEYGEN
				/* If less than v bytes pad with zeroes */
			} else if (Ijlen < v) {
				memset(I + j, 0, v - Ijlen);
				if (!BN_bn2bin(Ij, I + j + v - Ijlen))
					goto err;
#endif
			} else if (!BN_bn2bin (Ij, I + j))
				goto err;
		}
	}

err:
	PKCS12err(PKCS12_F_PKCS12_KEY_GEN_UNI, ERR_R_MALLOC_FAILURE);

end:
	free(Ai);
	free(B);
	free(D);
	free(I);
	BN_free(Ij);
	BN_free(Bpl1);
	EVP_MD_CTX_cleanup(&ctx);
	return ret;
}
Exemplo n.º 4
0
/* solves ax == 1 (mod n) */
BIGNUM *BN_mod_inverse(BIGNUM *in, BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
	{
	BIGNUM *A,*B,*X,*Y,*M,*D,*R=NULL;
	BIGNUM *T,*ret=NULL;
	int sign;

	bn_check_top(a);
	bn_check_top(n);

	BN_CTX_start(ctx);
	A = BN_CTX_get(ctx);
	B = BN_CTX_get(ctx);
	X = BN_CTX_get(ctx);
	D = BN_CTX_get(ctx);
	M = BN_CTX_get(ctx);
	Y = BN_CTX_get(ctx);
	if (Y == NULL) goto err;

	if (in == NULL)
		R=BN_new();
	else
		R=in;
	if (R == NULL) goto err;

	if (!BN_zero(X)) goto err;
	if (!BN_one(Y)) goto err;
	if (BN_copy(A,a) == NULL) goto err;
	if (BN_copy(B,n) == NULL) goto err;
	sign=1;

	while (!BN_is_zero(B))
		{
		if (!BN_div(D,M,A,B,ctx)) goto err;
		T=A;
		A=B;
		B=M;
		/* T has a struct, M does not */

		if (!BN_mul(T,D,X,ctx)) goto err;
		if (!BN_add(T,T,Y)) goto err;
		M=Y;
		Y=X;
		X=T;
		sign= -sign;
		}
	if (sign < 0)
		{
		if (!BN_sub(Y,n,Y)) goto err;
		}

	if (BN_is_one(A))
		{ if (!BN_mod(R,Y,n,ctx)) goto err; }
	else
		{
		BNerr(BN_F_BN_MOD_INVERSE,BN_R_NO_INVERSE);
		goto err;
		}
	ret=R;
err:
	if ((ret == NULL) && (in == NULL)) BN_free(R);
	BN_CTX_end(ctx);
	return(ret);
	}
Exemplo n.º 5
0
/*
 * Find the bignum ranges that produce a given prefix.
 */
static int
get_prefix_ranges(int addrtype, const char *pfx, BIGNUM **result,
		  BN_CTX *bnctx)
{
	int i, p, c;
	int zero_prefix = 0;
	int check_upper = 0;
	int b58pow, b58ceil, b58top = 0;
	int ret = -1;

	BIGNUM bntarg, bnceil, bnfloor;
	BIGNUM bnbase;
	BIGNUM *bnap, *bnbp, *bntp;
	BIGNUM *bnhigh = NULL, *bnlow = NULL, *bnhigh2 = NULL, *bnlow2 = NULL;
	BIGNUM bntmp, bntmp2;

	BN_init(&bntarg);
	BN_init(&bnceil);
	BN_init(&bnfloor);
	BN_init(&bnbase);
	BN_init(&bntmp);
	BN_init(&bntmp2);

	BN_set_word(&bnbase, 58);

	p = strlen(pfx);

	for (i = 0; i < p; i++) {
		c = vg_b58_reverse_map[(int)pfx[i]];
		if (c == -1) {
			fprintf(stderr,
				"Invalid character '%c' in prefix '%s'\n",
				pfx[i], pfx);
			goto out;
		}
		if (i == zero_prefix) {
			if (c == 0) {
				/* Add another zero prefix */
				zero_prefix++;
				if (zero_prefix > 19) {
					fprintf(stderr,
						"Prefix '%s' is too long\n",
						pfx);
					goto out;
				}
				continue;
			}

			/* First non-zero character */
			b58top = c;
			BN_set_word(&bntarg, c);

		} else {
			BN_set_word(&bntmp2, c);
			BN_mul(&bntmp, &bntarg, &bnbase, bnctx);
			BN_add(&bntarg, &bntmp, &bntmp2);
		}
	}

	/* Power-of-two ceiling and floor values based on leading 1s */
	BN_clear(&bntmp);
	BN_set_bit(&bntmp, 200 - (zero_prefix * 8));
	BN_sub(&bnceil, &bntmp, BN_value_one());
	BN_set_bit(&bnfloor, 192 - (zero_prefix * 8));

	bnlow = BN_new();
	bnhigh = BN_new();

	if (b58top) {
		/*
		 * If a non-zero was given in the prefix, find the
		 * numeric boundaries of the prefix.
		 */

		BN_copy(&bntmp, &bnceil);
		bnap = &bntmp;
		bnbp = &bntmp2;
		b58pow = 0;
		while (BN_cmp(bnap, &bnbase) > 0) {
			b58pow++;
			BN_div(bnbp, NULL, bnap, &bnbase, bnctx);
			bntp = bnap;
			bnap = bnbp;
			bnbp = bntp;
		}
		b58ceil = BN_get_word(bnap);

		if ((b58pow - (p - zero_prefix)) < 6) {
			/*
			 * Do not allow the prefix to constrain the
			 * check value, this is ridiculous.
			 */
			fprintf(stderr, "Prefix '%s' is too long\n", pfx);
			goto out;
		}

		BN_set_word(&bntmp2, b58pow - (p - zero_prefix));
		BN_exp(&bntmp, &bnbase, &bntmp2, bnctx);
		BN_mul(bnlow, &bntmp, &bntarg, bnctx);
		BN_sub(&bntmp2, &bntmp, BN_value_one());
		BN_add(bnhigh, bnlow, &bntmp2);

		if (b58top <= b58ceil) {
			/* Fill out the upper range too */
			check_upper = 1;
			bnlow2 = BN_new();
			bnhigh2 = BN_new();

			BN_mul(bnlow2, bnlow, &bnbase, bnctx);
			BN_mul(&bntmp2, bnhigh, &bnbase, bnctx);
			BN_set_word(&bntmp, 57);
			BN_add(bnhigh2, &bntmp2, &bntmp);

			/*
			 * Addresses above the ceiling will have one
			 * fewer "1" prefix in front than we require.
			 */
			if (BN_cmp(&bnceil, bnlow2) < 0) {
				/* High prefix is above the ceiling */
				check_upper = 0;
				BN_free(bnhigh2);
				bnhigh2 = NULL;
				BN_free(bnlow2);
				bnlow2 = NULL;
			}
			else if (BN_cmp(&bnceil, bnhigh2) < 0)
				/* High prefix is partly above the ceiling */
				BN_copy(bnhigh2, &bnceil);

			/*
			 * Addresses below the floor will have another
			 * "1" prefix in front instead of our target.
			 */
			if (BN_cmp(&bnfloor, bnhigh) >= 0) {
				/* Low prefix is completely below the floor */
				assert(check_upper);
				check_upper = 0;
				BN_free(bnhigh);
				bnhigh = bnhigh2;
				bnhigh2 = NULL;
				BN_free(bnlow);
				bnlow = bnlow2;
				bnlow2 = NULL;
			}			
			else if (BN_cmp(&bnfloor, bnlow) > 0) {
				/* Low prefix is partly below the floor */
				BN_copy(bnlow, &bnfloor);
			}
		}

	} else {
		BN_copy(bnhigh, &bnceil);
		BN_clear(bnlow);
	}

	/* Limit the prefix to the address type */
	BN_clear(&bntmp);
	BN_set_word(&bntmp, addrtype);
	BN_lshift(&bntmp2, &bntmp, 192);

	if (check_upper) {
		if (BN_cmp(&bntmp2, bnhigh2) > 0) {
			check_upper = 0;
			BN_free(bnhigh2);
			bnhigh2 = NULL;
			BN_free(bnlow2);
			bnlow2 = NULL;
		}
		else if (BN_cmp(&bntmp2, bnlow2) > 0)
			BN_copy(bnlow2, &bntmp2);
	}

	if (BN_cmp(&bntmp2, bnhigh) > 0) {
		if (!check_upper)
			goto not_possible;
		check_upper = 0;
		BN_free(bnhigh);
		bnhigh = bnhigh2;
		bnhigh2 = NULL;
		BN_free(bnlow);
		bnlow = bnlow2;
		bnlow2 = NULL;
	}
	else if (BN_cmp(&bntmp2, bnlow) > 0) {
		BN_copy(bnlow, &bntmp2);
	}

	BN_set_word(&bntmp, addrtype + 1);
	BN_lshift(&bntmp2, &bntmp, 192);

	if (check_upper) {
		if (BN_cmp(&bntmp2, bnlow2) < 0) {
			check_upper = 0;
			BN_free(bnhigh2);
			bnhigh2 = NULL;
			BN_free(bnlow2);
			bnlow2 = NULL;
		}
		else if (BN_cmp(&bntmp2, bnhigh2) < 0)
			BN_copy(bnlow2, &bntmp2);
	}

	if (BN_cmp(&bntmp2, bnlow) < 0) {
		if (!check_upper)
			goto not_possible;
		check_upper = 0;
		BN_free(bnhigh);
		bnhigh = bnhigh2;
		bnhigh2 = NULL;
		BN_free(bnlow);
		bnlow = bnlow2;
		bnlow2 = NULL;
	}
	else if (BN_cmp(&bntmp2, bnhigh) < 0) {
		BN_copy(bnhigh, &bntmp2);
	}

	/* Address ranges are complete */
	assert(check_upper || ((bnlow2 == NULL) && (bnhigh2 == NULL)));
	result[0] = bnlow;
	result[1] = bnhigh;
	result[2] = bnlow2;
	result[3] = bnhigh2;
	bnlow = NULL;
	bnhigh = NULL;
	bnlow2 = NULL;
	bnhigh2 = NULL;
	ret = 0;

	if (0) {
	not_possible:
		ret = -2;
	}

out:
	BN_clear_free(&bntarg);
	BN_clear_free(&bnceil);
	BN_clear_free(&bnfloor);
	BN_clear_free(&bnbase);
	BN_clear_free(&bntmp);
	BN_clear_free(&bntmp2);
	if (bnhigh)
		BN_free(bnhigh);
	if (bnlow)
		BN_free(bnlow);
	if (bnhigh2)
		BN_free(bnhigh2);
	if (bnlow2)
		BN_free(bnlow2);

	return ret;
}
Exemplo n.º 6
0
 bigint& bigint::operator += ( const bigint& a ){
   bigint tmp(*this);
   BN_add( tmp.n, n, a.n );
   std::swap(*this,tmp);
   return *this;
 }
Exemplo n.º 7
0
static struct wpabuf *
eap_pwd_build_commit_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
{
	struct wpabuf *req = NULL;
	BIGNUM *mask = NULL, *x = NULL, *y = NULL;
	u8 *scalar = NULL, *element = NULL;
	u16 offset;

	wpa_printf(MSG_DEBUG, "EAP-pwd: Commit/Request");

	if (((data->private_value = BN_new()) == NULL) ||
	    ((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
	    ((data->my_scalar = BN_new()) == NULL) ||
	    ((mask = BN_new()) == NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): scalar allocation "
			   "fail");
		goto fin;
	}

	BN_rand_range(data->private_value, data->grp->order);
	BN_rand_range(mask, data->grp->order);
	BN_add(data->my_scalar, data->private_value, mask);
	BN_mod(data->my_scalar, data->my_scalar, data->grp->order,
	       data->bnctx);

	if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
			  data->grp->pwe, mask, data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): element allocation "
			   "fail");
		eap_pwd_state(data, FAILURE);
		goto fin;
	}

	if (!EC_POINT_invert(data->grp->group, data->my_element, data->bnctx))
	{
		wpa_printf(MSG_INFO, "EAP-PWD (server): element inversion "
			   "fail");
		goto fin;
	}
	BN_free(mask);

	if (((x = BN_new()) == NULL) ||
	    ((y = BN_new()) == NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): point allocation "
			   "fail");
		goto fin;
	}
	if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
						 data->my_element, x, y,
						 data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): point assignment "
			   "fail");
		goto fin;
	}

	if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
	    ((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
	     NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): data allocation fail");
		goto fin;
	}

	/*
	 * bignums occupy as little memory as possible so one that is
	 * sufficiently smaller than the prime or order might need pre-pending
	 * with zeros.
	 */
	os_memset(scalar, 0, BN_num_bytes(data->grp->order));
	os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
	offset = BN_num_bytes(data->grp->order) -
		BN_num_bytes(data->my_scalar);
	BN_bn2bin(data->my_scalar, scalar + offset);

	offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
	BN_bn2bin(x, element + offset);
	offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
	BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);

	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
			    1 + (2 * BN_num_bytes(data->grp->prime)) +
			    BN_num_bytes(data->grp->order),
			    EAP_CODE_REQUEST, id);
	if (req == NULL)
		goto fin;
	wpabuf_put_u8(req, EAP_PWD_OPCODE_COMMIT_EXCH);

	/* We send the element as (x,y) followed by the scalar */
	wpabuf_put_data(req, element, (2 * BN_num_bytes(data->grp->prime)));
	wpabuf_put_data(req, scalar, BN_num_bytes(data->grp->order));

fin:
	os_free(scalar);
	os_free(element);
	BN_free(x);
	BN_free(y);
	if (req == NULL)
		eap_pwd_state(data, FAILURE);

	return req;
}
Exemplo n.º 8
0
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,
	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;

	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)
				{
				RAND_pseudo_bytes(seed, qsize);
				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 */
			EVP_Digest(seed, qsize, md,   NULL, evpmd, NULL);
			EVP_Digest(buf,  qsize, buf2, NULL, evpmd, NULL);
			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;
					}

				EVP_Digest(buf, qsize, md ,NULL, evpmd, NULL);

				/* 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(ctx)
		{
		BN_CTX_end(ctx);
		BN_CTX_free(ctx);
		}
	if (mont != NULL) BN_MONT_CTX_free(mont);
	return ok;
	}
Exemplo n.º 9
0
DSA *DSA_generate_parameters(int bits,
		unsigned char *seed_in, int seed_len,
		int *counter_ret, unsigned long *h_ret,
		void (*callback)(int, int, void *),
		void *cb_arg)
	{
	int ok=0;
	unsigned char seed[SHA_DIGEST_LENGTH];
	unsigned char md[SHA_DIGEST_LENGTH];
	unsigned char buf[SHA_DIGEST_LENGTH],buf2[SHA_DIGEST_LENGTH];
	BIGNUM *r0,*W,*X,*c,*test;
	BIGNUM *g=NULL,*q=NULL,*p=NULL;
	BN_MONT_CTX *mont=NULL;
	int k,n=0,i,b,m=0;
	int counter=0;
	int r=0;
	BN_CTX *ctx=NULL,*ctx2=NULL,*ctx3=NULL;
	unsigned int h=2;
	DSA *ret=NULL;

	if (bits < 512) bits=512;
	bits=(bits+63)/64*64;

	if (seed_len < 20)
		seed_in = NULL; /* seed buffer too small -- ignore */
	if (seed_len > 20) 
		seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED,
		                * but our internal buffers are restricted to 160 bits*/
	if ((seed_in != NULL) && (seed_len == 20))
		memcpy(seed,seed_in,seed_len);

	if ((ctx=BN_CTX_new()) == NULL) goto err;
	if ((ctx2=BN_CTX_new()) == NULL) goto err;
	if ((ctx3=BN_CTX_new()) == NULL) goto err;
	if ((ret=DSA_new()) == NULL) goto err;

	if ((mont=BN_MONT_CTX_new()) == NULL) goto err;

	BN_CTX_start(ctx2);
	r0 = BN_CTX_get(ctx2);
	g = BN_CTX_get(ctx2);
	W = BN_CTX_get(ctx2);
	q = BN_CTX_get(ctx2);
	X = BN_CTX_get(ctx2);
	c = BN_CTX_get(ctx2);
	p = BN_CTX_get(ctx2);
	test = BN_CTX_get(ctx2);
	if (test == NULL) goto err;

	if (!BN_lshift(test,BN_value_one(),bits-1)) goto err;

	for (;;)
		{
		for (;;) /* find q */
			{
			int seed_is_random;

			/* step 1 */
			if (callback != NULL) callback(0,m++,cb_arg);

			if (!seed_len)
				{
				RAND_pseudo_bytes(seed,SHA_DIGEST_LENGTH);
				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,SHA_DIGEST_LENGTH);
			memcpy(buf2,seed,SHA_DIGEST_LENGTH);
			/* precompute "SEED + 1" for step 7: */
			for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--)
				{
				buf[i]++;
				if (buf[i] != 0) break;
				}

			/* step 2 */
			EVP_Digest(seed,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL);
			EVP_Digest(buf,SHA_DIGEST_LENGTH,buf2,NULL,HASH, NULL);
			for (i=0; i<SHA_DIGEST_LENGTH; i++)
				md[i]^=buf2[i];

			/* step 3 */
			md[0]|=0x80;
			md[SHA_DIGEST_LENGTH-1]|=0x01;
			if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err;

			/* step 4 */
			r = BN_is_prime_fasttest(q, DSS_prime_checks, callback, ctx3, cb_arg, seed_is_random);
			if (r > 0)
				break;
			if (r != 0)
				goto err;

			/* do a callback call */
			/* step 5 */
			}

		if (callback != NULL) callback(2,0,cb_arg);
		if (callback != NULL) callback(3,0,cb_arg);

		/* step 6 */
		counter=0;
		/* "offset = 2" */

		n=(bits-1)/160;
		b=(bits-1)-n*160;

		for (;;)
			{
			if (callback != NULL && counter != 0)
				callback(0,counter,cb_arg);

			/* step 7 */
			if (!BN_zero(W)) goto err;
			/* now 'buf' contains "SEED + offset - 1" */
			for (k=0; k<=n; k++)
				{
				/* obtain "SEED + offset + k" by incrementing: */
				for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--)
					{
					buf[i]++;
					if (buf[i] != 0) break;
					}

				EVP_Digest(buf,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL);

				/* step 8 */
				if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0))
					goto err;
				if (!BN_lshift(r0,r0,160*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(p, DSS_prime_checks, callback, ctx3, cb_arg, 1);
				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 (callback != NULL) callback(2,1,cb_arg);

	/* 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 (callback != NULL) callback(3,1,cb_arg);

	ok=1;
err:
	if (!ok)
		{
		if (ret != NULL) DSA_free(ret);
		}
	else
		{
		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 ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20);
		if (counter_ret != NULL) *counter_ret=counter;
		if (h_ret != NULL) *h_ret=h;
		}
	if (ctx != NULL) BN_CTX_free(ctx);
	if (ctx2 != NULL)
		{
		BN_CTX_end(ctx2);
		BN_CTX_free(ctx2);
		}
	if (ctx3 != NULL) BN_CTX_free(ctx3);
	if (mont != NULL) BN_MONT_CTX_free(mont);
	return(ok?ret:NULL);
	}
Exemplo n.º 10
0
static void
eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
				struct eap_method_ret *ret,
				const struct wpabuf *reqData,
				const u8 *payload, size_t payload_len)
{
	EC_POINT *K = NULL, *point = NULL;
	BIGNUM *mask = NULL, *x = NULL, *y = NULL, *cofactor = NULL;
	u16 offset;
	u8 *ptr, *scalar = NULL, *element = NULL;
	size_t prime_len, order_len;

	if (data->state != PWD_Commit_Req) {
		ret->ignore = TRUE;
		goto fin;
	}

	prime_len = BN_num_bytes(data->grp->prime);
	order_len = BN_num_bytes(data->grp->order);

	if (payload_len != 2 * prime_len + order_len) {
		wpa_printf(MSG_INFO,
			   "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
			   (unsigned int) payload_len,
			   (unsigned int) (2 * prime_len + order_len));
		goto fin;
	}

	if (((data->private_value = BN_new()) == NULL) ||
	    ((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
	    ((cofactor = BN_new()) == NULL) ||
	    ((data->my_scalar = BN_new()) == NULL) ||
	    ((mask = BN_new()) == NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): scalar allocation fail");
		goto fin;
	}

	if (!EC_GROUP_get_cofactor(data->grp->group, cofactor, NULL)) {
		wpa_printf(MSG_INFO, "EAP-pwd (peer): unable to get cofactor "
			   "for curve");
		goto fin;
	}

	if (BN_rand_range(data->private_value, data->grp->order) != 1 ||
	    BN_rand_range(mask, data->grp->order) != 1 ||
	    BN_add(data->my_scalar, data->private_value, mask) != 1 ||
	    BN_mod(data->my_scalar, data->my_scalar, data->grp->order,
		   data->bnctx) != 1) {
		wpa_printf(MSG_INFO,
			   "EAP-pwd (peer): unable to get randomness");
		goto fin;
	}

	if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
			  data->grp->pwe, mask, data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): element allocation "
			   "fail");
		eap_pwd_state(data, FAILURE);
		goto fin;
	}

	if (!EC_POINT_invert(data->grp->group, data->my_element, data->bnctx))
	{
		wpa_printf(MSG_INFO, "EAP-PWD (peer): element inversion fail");
		goto fin;
	}
	BN_clear_free(mask);

	if (((x = BN_new()) == NULL) ||
	    ((y = BN_new()) == NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): point allocation fail");
		goto fin;
	}

	/* process the request */
	if (((data->server_scalar = BN_new()) == NULL) ||
	    ((data->k = BN_new()) == NULL) ||
	    ((K = EC_POINT_new(data->grp->group)) == NULL) ||
	    ((point = EC_POINT_new(data->grp->group)) == NULL) ||
	    ((data->server_element = EC_POINT_new(data->grp->group)) == NULL))
	{
		wpa_printf(MSG_INFO, "EAP-PWD (peer): peer data allocation "
			   "fail");
		goto fin;
	}

	/* element, x then y, followed by scalar */
	ptr = (u8 *) payload;
	BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), x);
	ptr += BN_num_bytes(data->grp->prime);
	BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), y);
	ptr += BN_num_bytes(data->grp->prime);
	BN_bin2bn(ptr, BN_num_bytes(data->grp->order), data->server_scalar);
	if (!EC_POINT_set_affine_coordinates_GFp(data->grp->group,
						 data->server_element, x, y,
						 data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): setting peer element "
			   "fail");
		goto fin;
	}

	/* check to ensure server's element is not in a small sub-group */
	if (BN_cmp(cofactor, BN_value_one())) {
		if (!EC_POINT_mul(data->grp->group, point, NULL,
				  data->server_element, cofactor, NULL)) {
			wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
				   "server element by order!\n");
			goto fin;
		}
		if (EC_POINT_is_at_infinity(data->grp->group, point)) {
			wpa_printf(MSG_INFO, "EAP-PWD (peer): server element "
				   "is at infinity!\n");
			goto fin;
		}
	}

	/* compute the shared key, k */
	if ((!EC_POINT_mul(data->grp->group, K, NULL, data->grp->pwe,
			   data->server_scalar, data->bnctx)) ||
	    (!EC_POINT_add(data->grp->group, K, K, data->server_element,
			   data->bnctx)) ||
	    (!EC_POINT_mul(data->grp->group, K, NULL, K, data->private_value,
			   data->bnctx))) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): computing shared key "
			   "fail");
		goto fin;
	}

	/* ensure that the shared key isn't in a small sub-group */
	if (BN_cmp(cofactor, BN_value_one())) {
		if (!EC_POINT_mul(data->grp->group, K, NULL, K, cofactor,
				  NULL)) {
			wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
				   "shared key point by order");
			goto fin;
		}
	}

	/*
	 * This check is strictly speaking just for the case above where
	 * co-factor > 1 but it was suggested that even though this is probably
	 * never going to happen it is a simple and safe check "just to be
	 * sure" so let's be safe.
	 */
	if (EC_POINT_is_at_infinity(data->grp->group, K)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): shared key point is at "
			   "infinity!\n");
		goto fin;
	}

	if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group, K, data->k,
						 NULL, data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to extract "
			   "shared secret from point");
		goto fin;
	}

	/* now do the response */
	if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
						 data->my_element, x, y,
						 data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): point assignment fail");
		goto fin;
	}

	if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
	    ((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
	     NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (peer): data allocation fail");
		goto fin;
	}

	/*
	 * bignums occupy as little memory as possible so one that is
	 * sufficiently smaller than the prime or order might need pre-pending
	 * with zeros.
	 */
	os_memset(scalar, 0, BN_num_bytes(data->grp->order));
	os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
	offset = BN_num_bytes(data->grp->order) -
		BN_num_bytes(data->my_scalar);
	BN_bn2bin(data->my_scalar, scalar + offset);

	offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
	BN_bn2bin(x, element + offset);
	offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
	BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);

	data->outbuf = wpabuf_alloc(BN_num_bytes(data->grp->order) +
				    2 * BN_num_bytes(data->grp->prime));
	if (data->outbuf == NULL)
		goto fin;

	/* we send the element as (x,y) follwed by the scalar */
	wpabuf_put_data(data->outbuf, element,
			2 * BN_num_bytes(data->grp->prime));
	wpabuf_put_data(data->outbuf, scalar, BN_num_bytes(data->grp->order));

fin:
	os_free(scalar);
	os_free(element);
	BN_clear_free(x);
	BN_clear_free(y);
	BN_clear_free(cofactor);
	EC_POINT_clear_free(K);
	EC_POINT_clear_free(point);
	if (data->outbuf == NULL)
		eap_pwd_state(data, FAILURE);
	else
		eap_pwd_state(data, PWD_Confirm_Req);
}
Exemplo n.º 11
0
int
BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx)
{
    if (!BN_add(r, a, b)) return 0;
    return BN_nnmod(r, r, m, ctx);
}
Exemplo n.º 12
0
static int probable_prime_dh_safe(BIGNUM *p, int bits, const BIGNUM *padd,
                                  const BIGNUM *rem, BN_CTX *ctx) {
  int i, ret = 0;
  BIGNUM *t1, *qadd, *q;

  bits--;
  BN_CTX_start(ctx);
  t1 = BN_CTX_get(ctx);
  q = BN_CTX_get(ctx);
  qadd = BN_CTX_get(ctx);
  if (qadd == NULL) {
    goto err;
  }

  if (!BN_rshift1(qadd, padd)) {
    goto err;
  }

  if (!BN_rand(q, bits, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ODD)) {
    goto err;
  }

  /* we need ((rnd-rem) % add) == 0 */
  if (!BN_mod(t1, q, qadd, ctx)) {
    goto err;
  }

  if (!BN_sub(q, q, t1)) {
    goto err;
  }

  if (rem == NULL) {
    if (!BN_add_word(q, 1)) {
      goto err;
    }
  } else {
    if (!BN_rshift1(t1, rem)) {
      goto err;
    }
    if (!BN_add(q, q, t1)) {
      goto err;
    }
  }

  /* we now have a random number 'rand' to test. */
  if (!BN_lshift1(p, q)) {
    goto err;
  }
  if (!BN_add_word(p, 1)) {
    goto err;
  }

loop:
  for (i = 1; i < NUMPRIMES; i++) {
    /* check that p and q are prime */
    /* check that for p and q
     * gcd(p-1,primes) == 1 (except for 2) */
    BN_ULONG pmod = BN_mod_word(p, (BN_ULONG)primes[i]);
    BN_ULONG qmod = BN_mod_word(q, (BN_ULONG)primes[i]);
    if (pmod == (BN_ULONG)-1 || qmod == (BN_ULONG)-1) {
      goto err;
    }
    if (pmod == 0 || qmod == 0) {
      if (!BN_add(p, p, padd)) {
        goto err;
      }
      if (!BN_add(q, q, qadd)) {
        goto err;
      }
      goto loop;
    }
  }

  ret = 1;

err:
  BN_CTX_end(ctx);
  return ret;
}
Exemplo n.º 13
0
static int mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx) {
  assert(ctx != NULL);

  assert(rsa->n != NULL);
  assert(rsa->e != NULL);
  assert(rsa->d != NULL);
  assert(rsa->p != NULL);
  assert(rsa->q != NULL);
  assert(rsa->dmp1 != NULL);
  assert(rsa->dmq1 != NULL);
  assert(rsa->iqmp != NULL);

  BIGNUM *r1, *m1, *vrfy;
  BIGNUM local_dmp1, local_dmq1, local_c, local_r1;
  BIGNUM *dmp1, *dmq1, *c, *pr1;
  int ret = 0;
  size_t i, num_additional_primes = 0;

  if (rsa->additional_primes != NULL) {
    num_additional_primes = sk_RSA_additional_prime_num(rsa->additional_primes);
  }

  BN_CTX_start(ctx);
  r1 = BN_CTX_get(ctx);
  m1 = BN_CTX_get(ctx);
  vrfy = BN_CTX_get(ctx);
  if (r1 == NULL ||
      m1 == NULL ||
      vrfy == NULL) {
    goto err;
  }

  {
    BIGNUM local_p, local_q;
    BIGNUM *p = NULL, *q = NULL;

    /* Make sure BN_mod_inverse in Montgomery intialization uses the
     * BN_FLG_CONSTTIME flag. */
    BN_init(&local_p);
    p = &local_p;
    BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);

    BN_init(&local_q);
    q = &local_q;
    BN_with_flags(q, rsa->q, BN_FLG_CONSTTIME);

    if (!BN_MONT_CTX_set_locked(&rsa->mont_p, &rsa->lock, p, ctx) ||
        !BN_MONT_CTX_set_locked(&rsa->mont_q, &rsa->lock, q, ctx)) {
      goto err;
    }
  }

  if (!BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx)) {
    goto err;
  }

  /* compute I mod q */
  c = &local_c;
  BN_with_flags(c, I, BN_FLG_CONSTTIME);
  if (!BN_mod(r1, c, rsa->q, ctx)) {
    goto err;
  }

  /* compute r1^dmq1 mod q */
  dmq1 = &local_dmq1;
  BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
  if (!BN_mod_exp_mont_consttime(m1, r1, dmq1, rsa->q, ctx, rsa->mont_q)) {
    goto err;
  }

  /* compute I mod p */
  c = &local_c;
  BN_with_flags(c, I, BN_FLG_CONSTTIME);
  if (!BN_mod(r1, c, rsa->p, ctx)) {
    goto err;
  }

  /* compute r1^dmp1 mod p */
  dmp1 = &local_dmp1;
  BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
  if (!BN_mod_exp_mont_consttime(r0, r1, dmp1, rsa->p, ctx, rsa->mont_p)) {
    goto err;
  }

  if (!BN_sub(r0, r0, m1)) {
    goto err;
  }
  /* This will help stop the size of r0 increasing, which does
   * affect the multiply if it optimised for a power of 2 size */
  if (BN_is_negative(r0)) {
    if (!BN_add(r0, r0, rsa->p)) {
      goto err;
    }
  }

  if (!BN_mul(r1, r0, rsa->iqmp, ctx)) {
    goto err;
  }

  /* Turn BN_FLG_CONSTTIME flag on before division operation */
  pr1 = &local_r1;
  BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);

  if (!BN_mod(r0, pr1, rsa->p, ctx)) {
    goto err;
  }

  /* If p < q it is occasionally possible for the correction of
   * adding 'p' if r0 is negative above to leave the result still
   * negative. This can break the private key operations: the following
   * second correction should *always* correct this rare occurrence.
   * This will *never* happen with OpenSSL generated keys because
   * they ensure p > q [steve] */
  if (BN_is_negative(r0)) {
    if (!BN_add(r0, r0, rsa->p)) {
      goto err;
    }
  }
  if (!BN_mul(r1, r0, rsa->q, ctx)) {
    goto err;
  }
  if (!BN_add(r0, r1, m1)) {
    goto err;
  }

  for (i = 0; i < num_additional_primes; i++) {
    /* multi-prime RSA. */
    BIGNUM local_exp, local_prime;
    BIGNUM *exp = &local_exp, *prime = &local_prime;
    RSA_additional_prime *ap =
        sk_RSA_additional_prime_value(rsa->additional_primes, i);

    BN_with_flags(exp, ap->exp, BN_FLG_CONSTTIME);
    BN_with_flags(prime, ap->prime, BN_FLG_CONSTTIME);

    /* c will already point to a BIGNUM with the correct flags. */
    if (!BN_mod(r1, c, prime, ctx)) {
      goto err;
    }

    if (!BN_MONT_CTX_set_locked(&ap->mont, &rsa->lock, prime, ctx) ||
        !BN_mod_exp_mont_consttime(m1, r1, exp, prime, ctx, ap->mont)) {
      goto err;
    }

    BN_set_flags(m1, BN_FLG_CONSTTIME);

    if (!BN_sub(m1, m1, r0) ||
        !BN_mul(m1, m1, ap->coeff, ctx) ||
        !BN_mod(m1, m1, prime, ctx) ||
        (BN_is_negative(m1) && !BN_add(m1, m1, prime)) ||
        !BN_mul(m1, m1, ap->r, ctx) ||
        !BN_add(r0, r0, m1)) {
      goto err;
    }
  }

  ret = 1;

err:
  BN_CTX_end(ctx);
  return ret;
}
Exemplo n.º 14
0
int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
	     BN_CTX *ctx)
	{
	int retn=0;

#ifdef MONT_WORD
	BIGNUM *n,*r;
	BN_ULONG *ap,*np,*rp,n0,v,*nrp;
	int al,nl,max,i,x,ri;

	BN_CTX_start(ctx);
	if ((r = BN_CTX_get(ctx)) == NULL) goto err;

	if (!BN_copy(r,a)) goto err;
	n= &(mont->N);

	ap=a->d;
	/* mont->ri is the size of mont->N in bits (rounded up
	   to the word size) */
	al=ri=mont->ri/BN_BITS2;
	
	nl=n->top;
	if ((al == 0) || (nl == 0)) { r->top=0; return(1); }

	max=(nl+al+1); /* allow for overflow (no?) XXX */
	if (bn_wexpand(r,max) == NULL) goto err;
	if (bn_wexpand(ret,max) == NULL) goto err;

	r->neg=a->neg^n->neg;
	np=n->d;
	rp=r->d;
	nrp= &(r->d[nl]);

	/* clear the top words of T */
#if 1
	for (i=r->top; i<max; i++) /* memset? XXX */
		r->d[i]=0;
#else
	memset(&(r->d[r->top]),0,(max-r->top)*sizeof(BN_ULONG)); 
#endif

	r->top=max;
	n0=mont->n0;

#ifdef BN_COUNT
	fprintf(stderr,"word BN_from_montgomery %d * %d\n",nl,nl);
#endif
	for (i=0; i<nl; i++)
		{
#ifdef __TANDEM
                {
                   long long t1;
                   long long t2;
                   long long t3;
                   t1 = rp[0] * (n0 & 0177777);
                   t2 = 037777600000l;
                   t2 = n0 & t2;
                   t3 = rp[0] & 0177777;
                   t2 = (t3 * t2) & BN_MASK2;
                   t1 = t1 + t2;
                   v=bn_mul_add_words(rp,np,nl,(BN_ULONG) t1);
                }
#else
		v=bn_mul_add_words(rp,np,nl,(rp[0]*n0)&BN_MASK2);
#endif
		nrp++;
		rp++;
		if (((nrp[-1]+=v)&BN_MASK2) >= v)
			continue;
		else
			{
			if (((++nrp[0])&BN_MASK2) != 0) continue;
			if (((++nrp[1])&BN_MASK2) != 0) continue;
			for (x=2; (((++nrp[x])&BN_MASK2) == 0); x++) ;
			}
		}
	bn_fix_top(r);
	
	/* mont->ri will be a multiple of the word size */
#if 0
	BN_rshift(ret,r,mont->ri);
#else
	ret->neg = r->neg;
	x=ri;
	rp=ret->d;
	ap= &(r->d[x]);
	if (r->top < x)
		al=0;
	else
		al=r->top-x;
	ret->top=al;
	al-=4;
	for (i=0; i<al; i+=4)
		{
		BN_ULONG t1,t2,t3,t4;
		
		t1=ap[i+0];
		t2=ap[i+1];
		t3=ap[i+2];
		t4=ap[i+3];
		rp[i+0]=t1;
		rp[i+1]=t2;
		rp[i+2]=t3;
		rp[i+3]=t4;
		}
	al+=4;
	for (; i<al; i++)
		rp[i]=ap[i];
#endif
#else /* !MONT_WORD */ 
	BIGNUM *t1,*t2;

	BN_CTX_start(ctx);
	t1 = BN_CTX_get(ctx);
	t2 = BN_CTX_get(ctx);
	if (t1 == NULL || t2 == NULL) goto err;
	
	if (!BN_copy(t1,a)) goto err;
	BN_mask_bits(t1,mont->ri);

	if (!BN_mul(t2,t1,&mont->Ni,ctx)) goto err;
	BN_mask_bits(t2,mont->ri);

	if (!BN_mul(t1,t2,&mont->N,ctx)) goto err;
	if (!BN_add(t2,a,t1)) goto err;
	if (!BN_rshift(ret,t2,mont->ri)) goto err;
#endif /* MONT_WORD */

	if (BN_ucmp(ret, &(mont->N)) >= 0)
		{
		if (!BN_usub(ret,ret,&(mont->N))) goto err;
		}
	retn=1;
 err:
	BN_CTX_end(ctx);
	return(retn);
	}
Exemplo n.º 15
0
static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in,
					BIGNUM **kinvp, BIGNUM **rp,
					const unsigned char *dgst, int dlen)
{
	BN_CTX   *ctx = NULL;
	BIGNUM	 *k = NULL, *r = NULL, *order = NULL, *X = NULL;
	EC_POINT *tmp_point=NULL;
	const EC_GROUP *group;
	int 	 ret = 0;

	if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL)
	{
		ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER);
		return 0;
	}

	if (ctx_in == NULL) 
	{
		if ((ctx = BN_CTX_new()) == NULL)
		{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,ERR_R_MALLOC_FAILURE);
			return 0;
		}
	}
	else
		ctx = ctx_in;

	k     = BN_new();	/* this value is later returned in *kinvp */
	r     = BN_new();	/* this value is later returned in *rp    */
	order = BN_new();
	X     = BN_new();
	if (!k || !r || !order || !X)
	{
		ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
		goto err;
	}
	if ((tmp_point = EC_POINT_new(group)) == NULL)
	{
		ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
		goto err;
	}
	if (!EC_GROUP_get_order(group, order, ctx))
	{
		ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
		goto err;
	}

	do
	{
		/* get random k */	
		do
#ifndef OPENSSL_NO_SHA512
			if (dgst != NULL)
			{
				if (!BN_generate_dsa_nonce(k, order, EC_KEY_get0_private_key(eckey),
							   dgst, dlen, ctx))
					{
					ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
						 ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
					goto err;
					}
			}
			else
#endif
			{
				if (!BN_rand_range(k, order))
				{
					ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
						 ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
					goto err;
				}
			}
		while (BN_is_zero(k));

		/* We do not want timing information to leak the length of k,
		 * so we compute G*k using an equivalent scalar of fixed
		 * bit-length. */

		if (!BN_add(k, k, order)) goto err;
		if (BN_num_bits(k) <= BN_num_bits(order))
			if (!BN_add(k, k, order)) goto err;

		/* compute r the x-coordinate of generator * k */
		if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx))
		{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
			goto err;
		}
		if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == NID_X9_62_prime_field)
		{
			if (!EC_POINT_get_affine_coordinates_GFp(group,
				tmp_point, X, NULL, ctx))
			{
				ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,ERR_R_EC_LIB);
				goto err;
			}
		}
#ifndef OPENSSL_NO_EC2M
		else /* NID_X9_62_characteristic_two_field */
		{
			if (!EC_POINT_get_affine_coordinates_GF2m(group,
				tmp_point, X, NULL, ctx))
			{
				ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,ERR_R_EC_LIB);
				goto err;
			}
		}
#endif
		if (!BN_nnmod(r, X, order, ctx))
		{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
			goto err;
		}
	}
	while (BN_is_zero(r));

	/* compute the inverse of k */
	if (EC_GROUP_get_mont_data(group) != NULL)
		{
		/* We want inverse in constant time, therefore we utilize the
		 * fact order must be prime and use Fermats Little Theorem
		 * instead. */
		if (!BN_set_word(X, 2) )
			{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
			goto err;
			}
		if (!BN_mod_sub(X, order, X, order, ctx))
			{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
			goto err;
			}
		BN_set_flags(X, BN_FLG_CONSTTIME);
		if (!BN_mod_exp_mont_consttime(k, k, X, order, ctx, EC_GROUP_get_mont_data(group)))
			{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
			goto err;
			}
		}
	else
		{
		if (!BN_mod_inverse(k, k, order, ctx))
			{
			ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
			goto err;	
			}
		}

	/* clear old values if necessary */
	if (*rp != NULL)
		BN_clear_free(*rp);
	if (*kinvp != NULL) 
		BN_clear_free(*kinvp);
	/* save the pre-computed values  */
	*rp    = r;
	*kinvp = k;
	ret = 1;
err:
	if (!ret)
	{
		if (k != NULL) BN_clear_free(k);
		if (r != NULL) BN_clear_free(r);
	}
	if (ctx_in == NULL) 
		BN_CTX_free(ctx);
	if (order != NULL)
		BN_free(order);
	if (tmp_point != NULL) 
		EC_POINT_free(tmp_point);
	if (X)
		BN_clear_free(X);
	return(ret);
}
Exemplo n.º 16
0
static int
ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
{
	BN_CTX   *ctx = NULL;
	BIGNUM	 *k = NULL, *r = NULL, *order = NULL, *X = NULL;
	EC_POINT *tmp_point = NULL;
	const EC_GROUP *group;
	int 	 ret = 0;

	if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
		ECDSAerror(ERR_R_PASSED_NULL_PARAMETER);
		return 0;
	}

	if (ctx_in == NULL) {
		if ((ctx = BN_CTX_new()) == NULL) {
			ECDSAerror(ERR_R_MALLOC_FAILURE);
			return 0;
		}
	} else
		ctx = ctx_in;

	k = BN_new();	/* this value is later returned in *kinvp */
	r = BN_new();	/* this value is later returned in *rp    */
	order = BN_new();
	X = BN_new();
	if (!k || !r || !order || !X) {
		ECDSAerror(ERR_R_MALLOC_FAILURE);
		goto err;
	}
	if ((tmp_point = EC_POINT_new(group)) == NULL) {
		ECDSAerror(ERR_R_EC_LIB);
		goto err;
	}
	if (!EC_GROUP_get_order(group, order, ctx)) {
		ECDSAerror(ERR_R_EC_LIB);
		goto err;
	}

	do {
		/* get random k */
		do
			if (!BN_rand_range(k, order)) {
				ECDSAerror(ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
				goto err;
			}
		while (BN_is_zero(k));

		/* We do not want timing information to leak the length of k,
		 * so we compute G*k using an equivalent scalar of fixed
		 * bit-length. */
		if (!BN_add(k, k, order))
			goto err;
		if (BN_num_bits(k) <= BN_num_bits(order))
			if (!BN_add(k, k, order))
				goto err;

		BN_set_flags(k, BN_FLG_CONSTTIME);

		/* compute r the x-coordinate of generator * k */
		if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) {
			ECDSAerror(ERR_R_EC_LIB);
			goto err;
		}
		if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==
		    NID_X9_62_prime_field) {
			if (!EC_POINT_get_affine_coordinates_GFp(group,
			    tmp_point, X, NULL, ctx)) {
				ECDSAerror(ERR_R_EC_LIB);
				goto err;
			}
		}
#ifndef OPENSSL_NO_EC2M
		else /* NID_X9_62_characteristic_two_field */
		{
			if (!EC_POINT_get_affine_coordinates_GF2m(group,
			    tmp_point, X, NULL, ctx)) {
				ECDSAerror(ERR_R_EC_LIB);
				goto err;
			}
		}
#endif
		if (!BN_nnmod(r, X, order, ctx)) {
			ECDSAerror(ERR_R_BN_LIB);
			goto err;
		}
	} while (BN_is_zero(r));

	/* compute the inverse of k */
	if (!BN_mod_inverse_ct(k, k, order, ctx)) {
		ECDSAerror(ERR_R_BN_LIB);
		goto err;
	}
	/* clear old values if necessary */
	BN_clear_free(*rp);
	BN_clear_free(*kinvp);
	/* save the pre-computed values  */
	*rp = r;
	*kinvp = k;
	ret = 1;

err:
	if (!ret) {
		BN_clear_free(k);
		BN_clear_free(r);
	}
	if (ctx_in == NULL)
		BN_CTX_free(ctx);
	BN_free(order);
	EC_POINT_free(tmp_point);
	BN_clear_free(X);
	return (ret);
}
Exemplo n.º 17
0
 bigint bigint::operator + ( const bigint& a )const {
   bigint tmp(*this);
   BN_add( tmp.n, n, a.n );
   return tmp;
 }
Exemplo n.º 18
0
static int ecdsa_sign_setup(const EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
                            BIGNUM **rp, const uint8_t *digest,
                            size_t digest_len) {
  BN_CTX *ctx = NULL;
  BIGNUM *k = NULL, *kinv = NULL, *r = NULL, *tmp = NULL;
  EC_POINT *tmp_point = NULL;
  const EC_GROUP *group;
  int ret = 0;

  if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
    OPENSSL_PUT_ERROR(ECDSA, ERR_R_PASSED_NULL_PARAMETER);
    return 0;
  }

  if (ctx_in == NULL) {
    if ((ctx = BN_CTX_new()) == NULL) {
      OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE);
      return 0;
    }
  } else {
    ctx = ctx_in;
  }

  k = BN_new();
  kinv = BN_new();  // this value is later returned in *kinvp
  r = BN_new();  // this value is later returned in *rp
  tmp = BN_new();
  if (k == NULL || kinv == NULL || r == NULL || tmp == NULL) {
    OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE);
    goto err;
  }
  tmp_point = EC_POINT_new(group);
  if (tmp_point == NULL) {
    OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB);
    goto err;
  }

  const BIGNUM *order = EC_GROUP_get0_order(group);

  // Check that the size of the group order is FIPS compliant (FIPS 186-4
  // B.5.2).
  if (BN_num_bits(order) < 160) {
    OPENSSL_PUT_ERROR(ECDSA, EC_R_INVALID_GROUP_ORDER);
    goto err;
  }

  do {
    // If possible, we'll include the private key and message digest in the k
    // generation. The |digest| argument is only empty if |ECDSA_sign_setup| is
    // being used.
    if (eckey->fixed_k != NULL) {
      if (!BN_copy(k, eckey->fixed_k)) {
        goto err;
      }
    } else if (digest_len > 0) {
      do {
        if (!BN_generate_dsa_nonce(k, order, EC_KEY_get0_private_key(eckey),
                                   digest, digest_len, ctx)) {
          OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
          goto err;
        }
      } while (BN_is_zero(k));
    } else if (!BN_rand_range_ex(k, 1, order)) {
      OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
      goto err;
    }

    // Compute the inverse of k. The order is a prime, so use Fermat's Little
    // Theorem. Note |ec_group_get_order_mont| may return NULL but
    // |bn_mod_inverse_prime| allows this.
    if (!bn_mod_inverse_prime(kinv, k, order, ctx,
                              ec_group_get_order_mont(group))) {
      OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB);
      goto err;
    }

    // We do not want timing information to leak the length of k,
    // so we compute G*k using an equivalent scalar of fixed
    // bit-length.

    if (!BN_add(k, k, order)) {
      goto err;
    }
    if (BN_num_bits(k) <= BN_num_bits(order)) {
      if (!BN_add(k, k, order)) {
        goto err;
      }
    }

    // compute r the x-coordinate of generator * k
    if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) {
      OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB);
      goto err;
    }
    if (!EC_POINT_get_affine_coordinates_GFp(group, tmp_point, tmp, NULL,
                                             ctx)) {
      OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB);
      goto err;
    }

    if (!BN_nnmod(r, tmp, order, ctx)) {
      OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB);
      goto err;
    }
  } while (BN_is_zero(r));

  // clear old values if necessary
  BN_clear_free(*rp);
  BN_clear_free(*kinvp);

  // save the pre-computed values
  *rp = r;
  *kinvp = kinv;
  ret = 1;

err:
  BN_clear_free(k);
  if (!ret) {
    BN_clear_free(kinv);
    BN_clear_free(r);
  }
  if (ctx_in == NULL) {
    BN_CTX_free(ctx);
  }
  EC_POINT_free(tmp_point);
  BN_clear_free(tmp);
  return ret;
}
Exemplo n.º 19
0
static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
	{
	BIGNUM *r1,*m1,*vrfy;
	BIGNUM local_dmp1,local_dmq1,local_c,local_r1;
	BIGNUM *dmp1,*dmq1,*c,*pr1;
	int ret=0;

	BN_CTX_start(ctx);
	r1 = BN_CTX_get(ctx);
	m1 = BN_CTX_get(ctx);
	vrfy = BN_CTX_get(ctx);

	{
		BIGNUM local_p, local_q;
		BIGNUM *p = NULL, *q = NULL;

		/* Make sure BN_mod_inverse in Montgomery intialization uses the
		 * BN_FLG_CONSTTIME flag (unless RSA_FLAG_NO_CONSTTIME is set)
		 */
		if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
			{
			BN_init(&local_p);
			p = &local_p;
			BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);

			BN_init(&local_q);
			q = &local_q;
			BN_with_flags(q, rsa->q, BN_FLG_CONSTTIME);
			}
		else
			{
			p = rsa->p;
			q = rsa->q;
			}

		if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
			{
			if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_p, CRYPTO_LOCK_RSA, p, ctx))
				goto err;
			if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_q, CRYPTO_LOCK_RSA, q, ctx))
				goto err;
			}
	}

	if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
		if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, CRYPTO_LOCK_RSA, rsa->n, ctx))
			goto err;

	/* compute I mod q */
	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
		{
		c = &local_c;
		BN_with_flags(c, I, BN_FLG_CONSTTIME);
		if (!BN_mod(r1,c,rsa->q,ctx)) goto err;
		}
	else
		{
		if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
		}

	/* compute r1^dmq1 mod q */
	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
		{
		dmq1 = &local_dmq1;
		BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
		}
	else
		dmq1 = rsa->dmq1;
	if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
		rsa->_method_mod_q)) goto err;

	/* compute I mod p */
	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
		{
		c = &local_c;
		BN_with_flags(c, I, BN_FLG_CONSTTIME);
		if (!BN_mod(r1,c,rsa->p,ctx)) goto err;
		}
	else
		{
		if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
		}

	/* compute r1^dmp1 mod p */
	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
		{
		dmp1 = &local_dmp1;
		BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
		}
	else
		dmp1 = rsa->dmp1;
	if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
		rsa->_method_mod_p)) goto err;

	if (!BN_sub(r0,r0,m1)) goto err;
	/* This will help stop the size of r0 increasing, which does
	 * affect the multiply if it optimised for a power of 2 size */
	if (BN_is_negative(r0))
		if (!BN_add(r0,r0,rsa->p)) goto err;

	if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;

	/* Turn BN_FLG_CONSTTIME flag on before division operation */
	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
		{
		pr1 = &local_r1;
		BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
		}
	else
		pr1 = r1;
	if (!BN_mod(r0,pr1,rsa->p,ctx)) goto err;

	/* If p < q it is occasionally possible for the correction of
	 * adding 'p' if r0 is negative above to leave the result still
	 * negative. This can break the private key operations: the following
	 * second correction should *always* correct this rare occurrence.
	 * This will *never* happen with OpenSSL generated keys because
	 * they ensure p > q [steve]
	 */
	if (BN_is_negative(r0))
		if (!BN_add(r0,r0,rsa->p)) goto err;
	if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
	if (!BN_add(r0,r1,m1)) goto err;

	if (rsa->e && rsa->n)
		{
		if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
		/* If 'I' was greater than (or equal to) rsa->n, the operation
		 * will be equivalent to using 'I mod n'. However, the result of
		 * the verify will *always* be less than 'n' so we don't check
		 * for absolute equality, just congruency. */
		if (!BN_sub(vrfy, vrfy, I)) goto err;
		if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
		if (BN_is_negative(vrfy))
			if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
		if (!BN_is_zero(vrfy))
			{
			/* 'I' and 'vrfy' aren't congruent mod n. Don't leak
			 * miscalculated CRT output, just do a raw (slower)
			 * mod_exp and return that instead. */

			BIGNUM local_d;
			BIGNUM *d = NULL;
		
			if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
				{
				d = &local_d;
				BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
				}
			else
				d = rsa->d;
			if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
						   rsa->_method_mod_n)) goto err;
			}
		}
	ret=1;
err:
	BN_CTX_end(ctx);
	return(ret);
	}
Exemplo n.º 20
0
int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
	   BN_CTX *ctx)
	{
	int norm_shift,i,j,loop;
	BIGNUM *tmp,wnum,*snum,*sdiv,*res;
	BN_ULONG *resp,*wnump;
	BN_ULONG d0,d1;
	int num_n,div_n;

	bn_check_top(num);
	bn_check_top(divisor);

	if (BN_is_zero(divisor))
		{
		BNerr(BN_F_BN_DIV,BN_R_DIV_BY_ZERO);
		return(0);
		}

	if (BN_ucmp(num,divisor) < 0)
		{
		if (rm != NULL)
			{ if (BN_copy(rm,num) == NULL) return(0); }
		if (dv != NULL) BN_zero(dv);
		return(1);
		}

	BN_CTX_start(ctx);
	tmp=BN_CTX_get(ctx);
	snum=BN_CTX_get(ctx);
	sdiv=BN_CTX_get(ctx);
	if (dv == NULL)
		res=BN_CTX_get(ctx);
	else	res=dv;
	if (sdiv==NULL || res == NULL) goto err;
	tmp->neg=0;

	/* First we normalise the numbers */
	norm_shift=BN_BITS2-((BN_num_bits(divisor))%BN_BITS2);
	if (!(BN_lshift(sdiv,divisor,norm_shift))) goto err;
	sdiv->neg=0;
	norm_shift+=BN_BITS2;
	if (!(BN_lshift(snum,num,norm_shift))) goto err;
	snum->neg=0;
	div_n=sdiv->top;
	num_n=snum->top;
	loop=num_n-div_n;

	/* Lets setup a 'window' into snum
	 * This is the part that corresponds to the current
	 * 'area' being divided */
	BN_init(&wnum);
	wnum.d=	 &(snum->d[loop]);
	wnum.top= div_n;
	wnum.dmax= snum->dmax+1; /* a bit of a lie */

	/* Get the top 2 words of sdiv */
	/* i=sdiv->top; */
	d0=sdiv->d[div_n-1];
	d1=(div_n == 1)?0:sdiv->d[div_n-2];

	/* pointer to the 'top' of snum */
	wnump= &(snum->d[num_n-1]);

	/* Setup to 'res' */
	res->neg= (num->neg^divisor->neg);
	if (!bn_wexpand(res,(loop+1))) goto err;
	res->top=loop;
	resp= &(res->d[loop-1]);

	/* space for temp */
	if (!bn_wexpand(tmp,(div_n+1))) goto err;

	if (BN_ucmp(&wnum,sdiv) >= 0)
		{
		if (!BN_usub(&wnum,&wnum,sdiv)) goto err;
		*resp=1;
		res->d[res->top-1]=1;
		}
	else
		res->top--;
	resp--;

	for (i=0; i<loop-1; i++)
		{
		BN_ULONG q,l0;
#if defined(BN_DIV3W) && !defined(NO_ASM)
		BN_ULONG bn_div_3_words(BN_ULONG*,BN_ULONG,BN_ULONG);
		q=bn_div_3_words(wnump,d1,d0);
#else
		BN_ULONG n0,n1,rem=0;

		n0=wnump[0];
		n1=wnump[-1];
		if (n0 == d0)
			q=BN_MASK2;
		else 			/* n0 < d0 */
			{
#ifdef BN_LLONG
			BN_ULLONG t2;

#if defined(BN_LLONG) && defined(BN_DIV2W) && !defined(bn_div_words)
			q=(BN_ULONG)(((((BN_ULLONG)n0)<<BN_BITS2)|n1)/d0);
#else
			q=bn_div_words(n0,n1,d0);
#endif

#ifndef REMAINDER_IS_ALREADY_CALCULATED
			/*
			 * rem doesn't have to be BN_ULLONG. The least we
			 * know it's less that d0, isn't it?
			 */
			rem=(n1-q*d0)&BN_MASK2;
#endif
			t2=(BN_ULLONG)d1*q;

			for (;;)
				{
				if (t2 <= ((((BN_ULLONG)rem)<<BN_BITS2)|wnump[-2]))
					break;
				q--;
				rem += d0;
				if (rem < d0) break; /* don't let rem overflow */
				t2 -= d1;
				}
#else /* !BN_LLONG */
			BN_ULONG t2l,t2h,ql,qh;

			q=bn_div_words(n0,n1,d0);
#ifndef REMAINDER_IS_ALREADY_CALCULATED
			rem=(n1-q*d0)&BN_MASK2;
#endif

#ifdef BN_UMULT_HIGH
			t2l = d1 * q;
			t2h = BN_UMULT_HIGH(d1,q);
#else
			t2l=LBITS(d1); t2h=HBITS(d1);
			ql =LBITS(q);  qh =HBITS(q);
			mul64(t2l,t2h,ql,qh); /* t2=(BN_ULLONG)d1*q; */
#endif

			for (;;)
				{
				if ((t2h < rem) ||
					((t2h == rem) && (t2l <= wnump[-2])))
					break;
				q--;
				rem += d0;
				if (rem < d0) break; /* don't let rem overflow */
				if (t2l < d1) t2h--; t2l -= d1;
				}
#endif /* !BN_LLONG */
			}
#endif /* !BN_DIV3W */

		l0=bn_mul_words(tmp->d,sdiv->d,div_n,q);
		wnum.d--; wnum.top++;
		tmp->d[div_n]=l0;
		for (j=div_n+1; j>0; j--)
			if (tmp->d[j-1]) break;
		tmp->top=j;

		j=wnum.top;
		if (!BN_sub(&wnum,&wnum,tmp)) goto err;

		snum->top=snum->top+wnum.top-j;

		if (wnum.neg)
			{
			q--;
			j=wnum.top;
			if (!BN_add(&wnum,&wnum,sdiv)) goto err;
			snum->top+=wnum.top-j;
			}
		*(resp--)=q;
		wnump--;
		}
	if (rm != NULL)
		{
		BN_rshift(rm,snum,norm_shift);
		rm->neg=num->neg;
		}
	BN_CTX_end(ctx);
	return(1);
err:
	BN_CTX_end(ctx);
	return(0);
	}
Exemplo n.º 21
0
static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
	{
	BIGNUM *r1,*m1,*vrfy;
	BIGNUM local_dmp1, local_dmq1;
	BIGNUM *dmp1, *dmq1;
	int ret=0;

	BN_CTX_start(ctx);
	r1 = BN_CTX_get(ctx);
	m1 = BN_CTX_get(ctx);
	vrfy = BN_CTX_get(ctx);

	MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
	MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
	MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);

	if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
	if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
		{
		dmq1 = &local_dmq1;
		BN_with_flags(dmq1, rsa->dmq1, BN_FLG_EXP_CONSTTIME);
		}
	else
		dmq1 = rsa->dmq1;
	if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
		rsa->_method_mod_q)) goto err;

	if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
	if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
		{
		dmp1 = &local_dmp1;
		BN_with_flags(dmp1, rsa->dmp1, BN_FLG_EXP_CONSTTIME);
		}
	else
		dmp1 = rsa->dmp1;
	if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
		rsa->_method_mod_p)) goto err;

	if (!BN_sub(r0,r0,m1)) goto err;
	/* This will help stop the size of r0 increasing, which does
	 * affect the multiply if it optimised for a power of 2 size */
	if (BN_is_negative(r0))
		if (!BN_add(r0,r0,rsa->p)) goto err;

	if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
	if (!BN_mod(r0,r1,rsa->p,ctx)) goto err;
	/* If p < q it is occasionally possible for the correction of
         * adding 'p' if r0 is negative above to leave the result still
	 * negative. This can break the private key operations: the following
	 * second correction should *always* correct this rare occurrence.
	 * This will *never* happen with OpenSSL generated keys because
         * they ensure p > q [steve]
         */
	if (BN_is_negative(r0))
		if (!BN_add(r0,r0,rsa->p)) goto err;
	if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
	if (!BN_add(r0,r1,m1)) goto err;

	if (rsa->e && rsa->n)
		{
		if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
		/* If 'I' was greater than (or equal to) rsa->n, the operation
		 * will be equivalent to using 'I mod n'. However, the result of
		 * the verify will *always* be less than 'n' so we don't check
		 * for absolute equality, just congruency. */
		if (!BN_sub(vrfy, vrfy, I)) goto err;
		if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
		if (BN_is_negative(vrfy))
			if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
		if (!BN_is_zero(vrfy))
			{
			/* 'I' and 'vrfy' aren't congruent mod n. Don't leak
			 * miscalculated CRT output, just do a raw (slower)
			 * mod_exp and return that instead. */

			BIGNUM local_d;
			BIGNUM *d = NULL;
		
			if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
				{
				d = &local_d;
				BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
				}
			else
				d = rsa->d;
			if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
						   rsa->_method_mod_n)) goto err;
			}
		}
	ret=1;
err:
	BN_CTX_end(ctx);
	return(ret);
	}
Exemplo n.º 22
0
static int probable_prime_dh_safe(BIGNUM *p, int bits, const BIGNUM *padd,
                                  const BIGNUM *rem, BN_CTX *ctx)
{
    int i, ret = 0;
    BIGNUM *t1, *qadd, *q;

    bits--;
    BN_CTX_start(ctx);
    t1 = BN_CTX_get(ctx);
    q = BN_CTX_get(ctx);
    qadd = BN_CTX_get(ctx);
    if (qadd == NULL)
        goto err;

    if (!BN_rshift1(qadd, padd))
        goto err;

    if (!BN_rand(q, bits, 0, 1))
        goto err;

    /* we need ((rnd-rem) % add) == 0 */
    if (!BN_mod(t1, q, qadd, ctx))
        goto err;
    if (!BN_sub(q, q, t1))
        goto err;
    if (rem == NULL) {
        if (!BN_add_word(q, 1))
            goto err;
    } else {
        if (!BN_rshift1(t1, rem))
            goto err;
        if (!BN_add(q, q, t1))
            goto err;
    }

    /* we now have a random number 'rand' to test. */
    if (!BN_lshift1(p, q))
        goto err;
    if (!BN_add_word(p, 1))
        goto err;

 loop:
    for (i = 1; i < NUMPRIMES; i++) {
        /* check that p and q are prime */
        /*
         * check that for p and q gcd(p-1,primes) == 1 (except for 2)
         */
        if ((BN_mod_word(p, (BN_ULONG)primes[i]) == 0) ||
            (BN_mod_word(q, (BN_ULONG)primes[i]) == 0)) {
            if (!BN_add(p, p, padd))
                goto err;
            if (!BN_add(q, q, qadd))
                goto err;
            goto loop;
        }
    }
    ret = 1;

 err:
    BN_CTX_end(ctx);
    bn_check_top(p);
    return (ret);
}
Exemplo n.º 23
0
static int
vg_prefix_context_add_patterns(vg_context_t *vcp,
			       const char ** const patterns, int npatterns)
{
	vg_prefix_context_t *vcpp = (vg_prefix_context_t *) vcp;
	prefix_case_iter_t caseiter;
	vg_prefix_t *vp, *vp2;
	BN_CTX *bnctx;
	BIGNUM bntmp, bntmp2, bntmp3;
	BIGNUM *ranges[4];
	int ret = 0;
	int i, impossible = 0;
	int case_impossible;
	unsigned long npfx;
	char *dbuf;

	bnctx = BN_CTX_new();
	BN_init(&bntmp);
	BN_init(&bntmp2);
	BN_init(&bntmp3);

	npfx = 0;
	for (i = 0; i < npatterns; i++) {
		if (!vcpp->vcp_caseinsensitive) {
			vp = NULL;
			ret = get_prefix_ranges(vcpp->base.vc_addrtype,
						patterns[i],
						ranges, bnctx);
			if (!ret) {
				vp = vg_prefix_add_ranges(&vcpp->vcp_avlroot,
							  patterns[i],
							  ranges, NULL);
			}

		} else {
			/* Case-enumerate the prefix */
			if (!prefix_case_iter_init(&caseiter, patterns[i])) {
				fprintf(stderr,
					"Prefix '%s' is too long\n",
					patterns[i]);
				continue;
			}

			if (caseiter.ci_nbits > 16) {
				fprintf(stderr,
					"WARNING: Prefix '%s' has "
					"2^%d case-varied derivatives\n",
					patterns[i], caseiter.ci_nbits);
			}

			case_impossible = 0;
			vp = NULL;
			do {
				ret = get_prefix_ranges(vcpp->base.vc_addrtype,
							caseiter.ci_prefix,
							ranges, bnctx);
				if (ret == -2) {
					case_impossible++;
					ret = 0;
					continue;
				}
				if (ret)
					break;
				vp2 = vg_prefix_add_ranges(&vcpp->vcp_avlroot,
							   patterns[i],
							   ranges,
							   vp);
				if (!vp2) {
					ret = -1;
					break;
				}
				if (!vp)
					vp = vp2;

			} while (prefix_case_iter_next(&caseiter));

			if (!vp && case_impossible)
				ret = -2;

			if (ret && vp) {
				vg_prefix_delete(&vcpp->vcp_avlroot, vp);
				vp = NULL;
			}
		}

		if (ret == -2) {
			fprintf(stderr,
				"Prefix '%s' not possible\n", patterns[i]);
			impossible++;
		}

		if (!vp)
			continue;

		npfx++;

		/* Determine the probability of finding a match */
		vg_prefix_range_sum(vp, &bntmp, &bntmp2);
		BN_add(&bntmp2, &vcpp->vcp_difficulty, &bntmp);
		BN_copy(&vcpp->vcp_difficulty, &bntmp2);

		if (vcp->vc_verbose > 1) {
			BN_clear(&bntmp2);
			BN_set_bit(&bntmp2, 192);
			BN_div(&bntmp3, NULL, &bntmp2, &bntmp, bnctx);

			dbuf = BN_bn2dec(&bntmp3);
			fprintf(stderr,
				"Prefix difficulty: %20s %s\n",
				dbuf, patterns[i]);
			OPENSSL_free(dbuf);
		}
	}

	vcpp->base.vc_npatterns += npfx;
	vcpp->base.vc_npatterns_start += npfx;

	if (!npfx && impossible) {
		const char *ats = "bitcoin", *bw = "\"1\"";
		switch (vcpp->base.vc_addrtype) {
		case 5:
			ats = "bitcoin script";
			bw = "\"3\"";
			break;
		case 111:
			ats = "testnet";
			bw = "\"m\" or \"n\"";
			break;
		case 52:
			ats = "namecoin";
			bw = "\"M\" or \"N\"";
			break;
		default:
			break;
		}
		fprintf(stderr,
			"Hint: valid %s addresses begin with %s\n", ats, bw);
	}

	if (npfx)
		vg_prefix_context_next_difficulty(vcpp, &bntmp, &bntmp2, bnctx);

	ret = (npfx != 0);

	BN_clear_free(&bntmp);
	BN_clear_free(&bntmp2);
	BN_clear_free(&bntmp3);
	BN_CTX_free(bnctx);
	return ret;
}
Exemplo n.º 24
0
static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
                            BIGNUM **rp)
{
    BN_CTX *ctx = NULL;
    BIGNUM *k = NULL, *r = NULL, *order = NULL, *X = NULL;
    EC_POINT *tmp_point = NULL;
    const EC_GROUP *group;
    int ret = 0;
    int order_bits;

    if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
        ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }

    if (ctx_in == NULL) {
        if ((ctx = BN_CTX_new()) == NULL) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
            return 0;
        }
    } else
        ctx = ctx_in;

    k = BN_new();               /* this value is later returned in *kinvp */
    r = BN_new();               /* this value is later returned in *rp */
    order = BN_new();
    X = BN_new();
    if (!k || !r || !order || !X) {
        ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    if ((tmp_point = EC_POINT_new(group)) == NULL) {
        ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
        goto err;
    }
    if (!EC_GROUP_get_order(group, order, ctx)) {
        ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
        goto err;
    }

    /* Preallocate space */
    order_bits = BN_num_bits(order);
    if (!BN_set_bit(k, order_bits)
        || !BN_set_bit(r, order_bits)
        || !BN_set_bit(X, order_bits))
        goto err;

    do {
        /* get random k */
        do
            if (!BN_rand_range(k, order)) {
                ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
                         ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
                goto err;
            }
        while (BN_is_zero(k)) ;

        /*
         * We do not want timing information to leak the length of k, so we
         * compute G*k using an equivalent scalar of fixed bit-length.
         *
         * We unconditionally perform both of these additions to prevent a
         * small timing information leakage.  We then choose the sum that is
         * one bit longer than the order.  This guarantees the code
         * path used in the constant time implementations elsewhere.
         *
         * TODO: revisit the BN_copy aiming for a memory access agnostic
         * conditional copy.
         */
        if (!BN_add(r, k, order)
            || !BN_add(X, r, order)
            || !BN_copy(k, BN_num_bits(r) > order_bits ? r : X))
            goto err;

        /* compute r the x-coordinate of generator * k */
        if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
            goto err;
        }
        if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==
            NID_X9_62_prime_field) {
            if (!EC_POINT_get_affine_coordinates_GFp
                (group, tmp_point, X, NULL, ctx)) {
                ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
                goto err;
            }
        }
#ifndef OPENSSL_NO_EC2M
        else {                  /* NID_X9_62_characteristic_two_field */

            if (!EC_POINT_get_affine_coordinates_GF2m(group,
                                                      tmp_point, X, NULL,
                                                      ctx)) {
                ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
                goto err;
            }
        }
#endif
        if (!BN_nnmod(r, X, order, ctx)) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
            goto err;
        }
    }
    while (BN_is_zero(r));

    /* compute the inverse of k */
    if (EC_GROUP_get_mont_data(group) != NULL) {
        /*
         * We want inverse in constant time, therefore we utilize the fact
         * order must be prime and use Fermats Little Theorem instead.
         */
        if (!BN_set_word(X, 2)) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
            goto err;
        }
        if (!BN_mod_sub(X, order, X, order, ctx)) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
            goto err;
        }
        BN_set_flags(X, BN_FLG_CONSTTIME);
        if (!BN_mod_exp_mont_consttime
            (k, k, X, order, ctx, EC_GROUP_get_mont_data(group))) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
            goto err;
        }
    } else {
        if (!BN_mod_inverse(k, k, order, ctx)) {
            ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
            goto err;
        }
    }

    /* clear old values if necessary */
    if (*rp != NULL)
        BN_clear_free(*rp);
    if (*kinvp != NULL)
        BN_clear_free(*kinvp);
    /* save the pre-computed values  */
    *rp = r;
    *kinvp = k;
    ret = 1;
 err:
    if (!ret) {
        if (k != NULL)
            BN_clear_free(k);
        if (r != NULL)
            BN_clear_free(r);
    }
    if (ctx_in == NULL)
        BN_CTX_free(ctx);
    if (order != NULL)
        BN_free(order);
    if (tmp_point != NULL)
        EC_POINT_free(tmp_point);
    if (X)
        BN_clear_free(X);
    return (ret);
}
Exemplo n.º 25
0
// Perform ECDSA key recovery (see SEC1 4.1.6) for curves over (mod p)-fields
// recid selects which key is recovered
// if check is non-zero, additional checks are performed
int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check)
{
    if (!eckey) return 0;

    int ret = 0;
    BN_CTX *ctx = NULL;

    BIGNUM *x = NULL;
    BIGNUM *e = NULL;
    BIGNUM *order = NULL;
    BIGNUM *sor = NULL;
    BIGNUM *eor = NULL;
    BIGNUM *field = NULL;
    EC_POINT *R = NULL;
    EC_POINT *O = NULL;
    EC_POINT *Q = NULL;
    BIGNUM *rr = NULL;
    BIGNUM *zero = NULL;
    int n = 0;
    int i = recid / 2;

    const EC_GROUP *group = EC_KEY_get0_group(eckey);
    if ((ctx = BN_CTX_new()) == NULL) { ret = -1; goto err; }
    BN_CTX_start(ctx);
    order = BN_CTX_get(ctx);
    if (!EC_GROUP_get_order(group, order, ctx)) { ret = -2; goto err; }
    x = BN_CTX_get(ctx);
    if (!BN_copy(x, order)) { ret=-1; goto err; }
    if (!BN_mul_word(x, i)) { ret=-1; goto err; }
    if (!BN_add(x, x, ecsig->r)) { ret=-1; goto err; }
    field = BN_CTX_get(ctx);
    if (!EC_GROUP_get_curve_GFp(group, field, NULL, NULL, ctx)) { ret=-2; goto err; }
    if (BN_cmp(x, field) >= 0) { ret=0; goto err; }
    if ((R = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
    if (!EC_POINT_set_compressed_coordinates_GFp(group, R, x, recid % 2, ctx)) { ret=0; goto err; }
    if (check)
    {
        if ((O = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
        if (!EC_POINT_mul(group, O, NULL, R, order, ctx)) { ret=-2; goto err; }
        if (!EC_POINT_is_at_infinity(group, O)) { ret = 0; goto err; }
    }
    if ((Q = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
    n = EC_GROUP_get_degree(group);
    e = BN_CTX_get(ctx);
    if (!BN_bin2bn(msg, msglen, e)) { ret=-1; goto err; }
    if (8*msglen > n) BN_rshift(e, e, 8-(n & 7));
    zero = BN_CTX_get(ctx);
    if (!BN_zero(zero)) { ret=-1; goto err; }
    if (!BN_mod_sub(e, zero, e, order, ctx)) { ret=-1; goto err; }
    rr = BN_CTX_get(ctx);
    if (!BN_mod_inverse(rr, ecsig->r, order, ctx)) { ret=-1; goto err; }
    sor = BN_CTX_get(ctx);
    if (!BN_mod_mul(sor, ecsig->s, rr, order, ctx)) { ret=-1; goto err; }
    eor = BN_CTX_get(ctx);
    if (!BN_mod_mul(eor, e, rr, order, ctx)) { ret=-1; goto err; }
    if (!EC_POINT_mul(group, Q, eor, R, sor, ctx)) { ret=-2; goto err; }
    if (!EC_KEY_set_public_key(eckey, Q)) { ret=-2; goto err; }

    ret = 1;

err:
    if (ctx) {
        BN_CTX_end(ctx);
        BN_CTX_free(ctx);
    }
    if (R != NULL) EC_POINT_free(R);
    if (O != NULL) EC_POINT_free(O);
    if (Q != NULL) EC_POINT_free(Q);
    return ret;
}
Exemplo n.º 26
0
Arquivo: srp.c Projeto: ucodev/libsidp
/* Out: bytes_B, len_B.
 * 
 * On failure, bytes_B will be set to NULL and len_B will be set to 0
 */
struct SRPVerifier *  srp_verifier_new( SRP_HashAlgorithm alg, SRP_NGType ng_type, const char * username,
                                        const unsigned char * bytes_s, int len_s, 
                                        const unsigned char * bytes_v, int len_v,
                                        const unsigned char * bytes_A, int len_A,
                                        const unsigned char ** bytes_B, int * len_B,
                                        const char * n_hex, const char * g_hex )
{
    BIGNUM     *s    = BN_bin2bn(bytes_s, len_s, NULL);
    BIGNUM     *v    = BN_bin2bn(bytes_v, len_v, NULL);
    BIGNUM     *A    = BN_bin2bn(bytes_A, len_A, NULL);
    BIGNUM     *u    = 0;
    BIGNUM     *B    = BN_new();
    BIGNUM     *S    = BN_new();
    BIGNUM     *b    = BN_new();
    BIGNUM     *k    = 0;
    BIGNUM     *tmp1 = BN_new();
    BIGNUM     *tmp2 = BN_new();
    BN_CTX     *ctx  = BN_CTX_new();
    int         ulen = strlen(username) + 1;
    NGConstant *ng   = new_ng( ng_type, n_hex, g_hex );
    
    struct SRPVerifier * ver = (struct SRPVerifier *) malloc( sizeof(struct SRPVerifier) );

    init_random(); /* Only happens once */
    
    ver->username = (char *) malloc( ulen );
    ver->hash_alg = alg;
    ver->ng       = ng;
    
    memcpy( (char*)ver->username, username, ulen );
    
    ver->authenticated = 0;
        
    /* SRP-6a safety check */
    BN_mod(tmp1, A, ng->N, ctx);
    if ( !BN_is_zero(tmp1) )
    {        
        BN_rand(b, 256, -1, 0);
        
        k = H_nn(alg, ng->N, ng->g);
        
        /* B = kv + g^b */
        BN_mul(tmp1, k, v, ctx);
        BN_mod_exp(tmp2, ng->g, b, ng->N, ctx);
        BN_add(B, tmp1, tmp2);
        
        u = H_nn(alg, A, B);
        
        /* S = (A *(v^u)) ^ b */
        BN_mod_exp(tmp1, v, u, ng->N, ctx);
        BN_mul(tmp2, A, tmp1, ctx);
        BN_mod_exp(S, tmp2, b, ng->N, ctx);

        hash_num(alg, S, ver->session_key);
        
        calculate_M( alg, ng, ver->M, username, s, A, B, ver->session_key );
        calculate_H_AMK( alg, ver->H_AMK, A, ver->M, ver->session_key );
        
        *len_B   = BN_num_bytes(B);
        *bytes_B = (const unsigned char *) malloc( *len_B );
        
        BN_bn2bin( B, (unsigned char *) *bytes_B );
        
        ver->bytes_B = *bytes_B;
    }
    else
    {
        *len_B   = 0;
        *bytes_B = NULL;
    }
    
    BN_free(s);
    BN_free(v);
    BN_free(A);
    if (u) BN_free(u);
    if (k) BN_free(k);
    BN_free(B);
    BN_free(S);
    BN_free(b);
    BN_free(tmp1);
    BN_free(tmp2);
    BN_CTX_free(ctx);
    
    return ver;
}
Exemplo n.º 27
0
static void eap_pwd_build_commit_req(struct eap_sm *sm,
				     struct eap_pwd_data *data, u8 id)
{
	BIGNUM *mask = NULL, *x = NULL, *y = NULL;
	u8 *scalar = NULL, *element = NULL;
	u16 offset;

	wpa_printf(MSG_DEBUG, "EAP-pwd: Commit/Request");
	/*
	 * if we're fragmenting then we already have an commit request, just
	 * return
	 */
	if (data->out_frag_pos)
		return;

	if (((data->private_value = BN_new()) == NULL) ||
	    ((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
	    ((data->my_scalar = BN_new()) == NULL) ||
	    ((mask = BN_new()) == NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): scalar allocation "
			   "fail");
		goto fin;
	}

	if (BN_rand_range(data->private_value, data->grp->order) != 1 ||
	    BN_rand_range(mask, data->grp->order) != 1 ||
	    BN_add(data->my_scalar, data->private_value, mask) != 1 ||
	    BN_mod(data->my_scalar, data->my_scalar, data->grp->order,
		   data->bnctx) != 1) {
		wpa_printf(MSG_INFO,
			   "EAP-pwd (server): unable to get randomness");
		goto fin;
	}

	if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
			  data->grp->pwe, mask, data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): element allocation "
			   "fail");
		eap_pwd_state(data, FAILURE);
		goto fin;
	}

	if (!EC_POINT_invert(data->grp->group, data->my_element, data->bnctx))
	{
		wpa_printf(MSG_INFO, "EAP-PWD (server): element inversion "
			   "fail");
		goto fin;
	}
	BN_clear_free(mask);

	if (((x = BN_new()) == NULL) ||
	    ((y = BN_new()) == NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): point allocation "
			   "fail");
		goto fin;
	}
	if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
						 data->my_element, x, y,
						 data->bnctx)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): point assignment "
			   "fail");
		goto fin;
	}

	if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
	    ((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
	     NULL)) {
		wpa_printf(MSG_INFO, "EAP-PWD (server): data allocation fail");
		goto fin;
	}

	/*
	 * bignums occupy as little memory as possible so one that is
	 * sufficiently smaller than the prime or order might need pre-pending
	 * with zeros.
	 */
	os_memset(scalar, 0, BN_num_bytes(data->grp->order));
	os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
	offset = BN_num_bytes(data->grp->order) -
		BN_num_bytes(data->my_scalar);
	BN_bn2bin(data->my_scalar, scalar + offset);

	offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
	BN_bn2bin(x, element + offset);
	offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
	BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);

	data->outbuf = wpabuf_alloc(2 * BN_num_bytes(data->grp->prime) +
				    BN_num_bytes(data->grp->order));
	if (data->outbuf == NULL)
		goto fin;

	/* We send the element as (x,y) followed by the scalar */
	wpabuf_put_data(data->outbuf, element,
			2 * BN_num_bytes(data->grp->prime));
	wpabuf_put_data(data->outbuf, scalar, BN_num_bytes(data->grp->order));

fin:
	os_free(scalar);
	os_free(element);
	BN_clear_free(x);
	BN_clear_free(y);
	if (data->outbuf == NULL)
		eap_pwd_state(data, FAILURE);
}
Exemplo n.º 28
0
Arquivo: srp.c Projeto: ucodev/libsidp
/* Output: bytes_M. Buffer length is SHA512_DIGEST_LENGTH */
void  srp_user_process_challenge( struct SRPUser * usr, 
                                  const unsigned char * bytes_s, int len_s, 
                                  const unsigned char * bytes_B, int len_B,
                                  const unsigned char ** bytes_M, int * len_M )
{
    BIGNUM *s    = BN_bin2bn(bytes_s, len_s, NULL);
    BIGNUM *B    = BN_bin2bn(bytes_B, len_B, NULL);
    BIGNUM *u    = 0;
    BIGNUM *x    = 0;
    BIGNUM *k    = 0;
    BIGNUM *v    = BN_new();
    BIGNUM *tmp1 = BN_new();
    BIGNUM *tmp2 = BN_new();
    BIGNUM *tmp3 = BN_new();
    BN_CTX *ctx  = BN_CTX_new();
    
    u = H_nn(usr->hash_alg, usr->A, B);
    
    x = calculate_x( usr->hash_alg, s, usr->username, usr->password, usr->password_len );
    
    k = H_nn(usr->hash_alg, usr->ng->N, usr->ng->g);
    
    /* SRP-6a safety check */
    if ( !BN_is_zero(B) && !BN_is_zero(u) )
    {
        BN_mod_exp(v, usr->ng->g, x, usr->ng->N, ctx);
        
        /* S = (B - k*(g^x)) ^ (a + ux) */
        BN_mul(tmp1, u, x, ctx);
        BN_add(tmp2, usr->a, tmp1);             /* tmp2 = (a + ux)      */
        BN_mod_exp(tmp1, usr->ng->g, x, usr->ng->N, ctx);
        BN_mul(tmp3, k, tmp1, ctx);             /* tmp3 = k*(g^x)       */
        BN_sub(tmp1, B, tmp3);                  /* tmp1 = (B - K*(g^x)) */
        BN_mod_exp(usr->S, tmp1, tmp2, usr->ng->N, ctx);

        hash_num(usr->hash_alg, usr->S, usr->session_key);
        
        calculate_M( usr->hash_alg, usr->ng, usr->M, usr->username, s, usr->A, B, usr->session_key );
        calculate_H_AMK( usr->hash_alg, usr->H_AMK, usr->A, usr->M, usr->session_key );
        
        *bytes_M = usr->M;
        if (len_M)
            *len_M = hash_length( usr->hash_alg );
    }
    else
    {
        *bytes_M = NULL;
        if (len_M) 
            *len_M   = 0;
    }
    
    BN_free(s);
    BN_free(B);
    BN_free(u);
    BN_free(x);
    BN_free(k);
    BN_free(v);
    BN_free(tmp1);
    BN_free(tmp2);
    BN_free(tmp3);
    BN_CTX_free(ctx);
}
Exemplo n.º 29
0
int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
                      const EC_POINT *b, BN_CTX *ctx)
{
    int (*field_mul) (const EC_GROUP *, BIGNUM *, const BIGNUM *,
                      const BIGNUM *, BN_CTX *);
    int (*field_sqr) (const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *);
    const BIGNUM *p;
    BN_CTX *new_ctx = NULL;
    BIGNUM *n0, *n1, *n2, *n3, *n4, *n5, *n6;
    int ret = 0;

    if (a == b)
        return EC_POINT_dbl(group, r, a, ctx);
    if (EC_POINT_is_at_infinity(group, a))
        return EC_POINT_copy(r, b);
    if (EC_POINT_is_at_infinity(group, b))
        return EC_POINT_copy(r, a);

    field_mul = group->meth->field_mul;
    field_sqr = group->meth->field_sqr;
    p = group->field;

    if (ctx == NULL) {
        ctx = new_ctx = BN_CTX_new();
        if (ctx == NULL)
            return 0;
    }

    BN_CTX_start(ctx);
    n0 = BN_CTX_get(ctx);
    n1 = BN_CTX_get(ctx);
    n2 = BN_CTX_get(ctx);
    n3 = BN_CTX_get(ctx);
    n4 = BN_CTX_get(ctx);
    n5 = BN_CTX_get(ctx);
    n6 = BN_CTX_get(ctx);
    if (n6 == NULL)
        goto end;

    /*
     * Note that in this function we must not read components of 'a' or 'b'
     * once we have written the corresponding components of 'r'. ('r' might
     * be one of 'a' or 'b'.)
     */

    /* n1, n2 */
    if (b->Z_is_one) {
        if (!BN_copy(n1, a->X))
            goto end;
        if (!BN_copy(n2, a->Y))
            goto end;
        /* n1 = X_a */
        /* n2 = Y_a */
    } else {
        if (!field_sqr(group, n0, b->Z, ctx))
            goto end;
        if (!field_mul(group, n1, a->X, n0, ctx))
            goto end;
        /* n1 = X_a * Z_b^2 */

        if (!field_mul(group, n0, n0, b->Z, ctx))
            goto end;
        if (!field_mul(group, n2, a->Y, n0, ctx))
            goto end;
        /* n2 = Y_a * Z_b^3 */
    }

    /* n3, n4 */
    if (a->Z_is_one) {
        if (!BN_copy(n3, b->X))
            goto end;
        if (!BN_copy(n4, b->Y))
            goto end;
        /* n3 = X_b */
        /* n4 = Y_b */
    } else {
        if (!field_sqr(group, n0, a->Z, ctx))
            goto end;
        if (!field_mul(group, n3, b->X, n0, ctx))
            goto end;
        /* n3 = X_b * Z_a^2 */

        if (!field_mul(group, n0, n0, a->Z, ctx))
            goto end;
        if (!field_mul(group, n4, b->Y, n0, ctx))
            goto end;
        /* n4 = Y_b * Z_a^3 */
    }

    /* n5, n6 */
    if (!BN_mod_sub_quick(n5, n1, n3, p))
        goto end;
    if (!BN_mod_sub_quick(n6, n2, n4, p))
        goto end;
    /* n5 = n1 - n3 */
    /* n6 = n2 - n4 */

    if (BN_is_zero(n5)) {
        if (BN_is_zero(n6)) {
            /* a is the same point as b */
            BN_CTX_end(ctx);
            ret = EC_POINT_dbl(group, r, a, ctx);
            ctx = NULL;
            goto end;
        } else {
            /* a is the inverse of b */
            BN_zero(r->Z);
            r->Z_is_one = 0;
            ret = 1;
            goto end;
        }
    }

    /* 'n7', 'n8' */
    if (!BN_mod_add_quick(n1, n1, n3, p))
        goto end;
    if (!BN_mod_add_quick(n2, n2, n4, p))
        goto end;
    /* 'n7' = n1 + n3 */
    /* 'n8' = n2 + n4 */

    /* Z_r */
    if (a->Z_is_one && b->Z_is_one) {
        if (!BN_copy(r->Z, n5))
            goto end;
    } else {
        if (a->Z_is_one) {
            if (!BN_copy(n0, b->Z))
                goto end;
        } else if (b->Z_is_one) {
            if (!BN_copy(n0, a->Z))
                goto end;
        } else {
            if (!field_mul(group, n0, a->Z, b->Z, ctx))
                goto end;
        }
        if (!field_mul(group, r->Z, n0, n5, ctx))
            goto end;
    }
    r->Z_is_one = 0;
    /* Z_r = Z_a * Z_b * n5 */

    /* X_r */
    if (!field_sqr(group, n0, n6, ctx))
        goto end;
    if (!field_sqr(group, n4, n5, ctx))
        goto end;
    if (!field_mul(group, n3, n1, n4, ctx))
        goto end;
    if (!BN_mod_sub_quick(r->X, n0, n3, p))
        goto end;
    /* X_r = n6^2 - n5^2 * 'n7' */

    /* 'n9' */
    if (!BN_mod_lshift1_quick(n0, r->X, p))
        goto end;
    if (!BN_mod_sub_quick(n0, n3, n0, p))
        goto end;
    /* n9 = n5^2 * 'n7' - 2 * X_r */

    /* Y_r */
    if (!field_mul(group, n0, n0, n6, ctx))
        goto end;
    if (!field_mul(group, n5, n4, n5, ctx))
        goto end;               /* now n5 is n5^3 */
    if (!field_mul(group, n1, n2, n5, ctx))
        goto end;
    if (!BN_mod_sub_quick(n0, n0, n1, p))
        goto end;
    if (BN_is_odd(n0))
        if (!BN_add(n0, n0, p))
            goto end;
    /* now  0 <= n0 < 2*p,  and n0 is even */
    if (!BN_rshift1(r->Y, n0))
        goto end;
    /* Y_r = (n6 * 'n9' - 'n8' * 'n5^3') / 2 */

    ret = 1;

 end:
    if (ctx)                    /* otherwise we already called BN_CTX_end */
        BN_CTX_end(ctx);
    BN_CTX_free(new_ctx);
    return ret;
}
Exemplo n.º 30
0
/*
 * Computes gost_ec signature as DSA_SIG structure
 *
 */
DSA_SIG *gost_ec_sign(const unsigned char *dgst, int dlen, EC_KEY *eckey)
{
    DSA_SIG *newsig = NULL, *ret = NULL;
    BIGNUM *md = NULL;
    BIGNUM *order = NULL;
    const EC_GROUP *group;
    const BIGNUM *priv_key;
    BIGNUM *r = NULL, *s = NULL, *X = NULL, *tmp = NULL, *tmp2 = NULL,
        *k = NULL, *e = NULL;
    EC_POINT *C = NULL;
    BN_CTX *ctx;

    OPENSSL_assert(dgst != NULL && eckey != NULL);

    if (!(ctx = BN_CTX_new())) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
        return NULL;
    }

    BN_CTX_start(ctx);
    OPENSSL_assert(dlen == 32 || dlen == 64);
    md = hashsum2bn(dgst, dlen);
    newsig = DSA_SIG_new();
    if (!newsig || !md) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    group = EC_KEY_get0_group(eckey);
    if (!group) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
        goto err;
    }
    order = BN_CTX_get(ctx);
    if (!order || !EC_GROUP_get_order(group, order, ctx)) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
        goto err;
    }
    priv_key = EC_KEY_get0_private_key(eckey);
    if (!priv_key) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
        goto err;
    }
    e = BN_CTX_get(ctx);
    if (!e || !BN_mod(e, md, order, ctx)) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
        goto err;
    }
#ifdef DEBUG_SIGN
    fprintf(stderr, "digest as bignum=");
    BN_print_fp(stderr, md);
    fprintf(stderr, "\ndigest mod q=");
    BN_print_fp(stderr, e);
    fprintf(stderr, "\n");
#endif
    if (BN_is_zero(e)) {
        BN_one(e);
    }
    k = BN_CTX_get(ctx);
    C = EC_POINT_new(group);
    if (!k || !C) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    do {
        do {
            if (!BN_rand_range(k, order)) {
                GOSTerr(GOST_F_GOST_EC_SIGN, GOST_R_RNG_ERROR);
                goto err;
            }
            /*
             * To avoid timing information leaking the length of k,
             * compute C*k using an equivalent scalar of fixed bit-length */
            if (!BN_add(k, k, order)
                || (BN_num_bits(k) <= BN_num_bits(order)
                    && !BN_add(k, k, order))) {
                goto err;
            }
            if (!EC_POINT_mul(group, C, k, NULL, NULL, ctx)) {
                GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_EC_LIB);
                goto err;
            }
            if (!X)
                X = BN_CTX_get(ctx);
            if (!r)
                r = BN_CTX_get(ctx);
            if (!X || !r) {
                GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
                goto err;
            }
            if (!EC_POINT_get_affine_coordinates_GFp(group, C, X, NULL, ctx)) {
                GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_EC_LIB);
                goto err;
            }

            if (!BN_nnmod(r, X, order, ctx)) {
                GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
                goto err;
            }
        }
        while (BN_is_zero(r));
        /* s =  (r*priv_key+k*e) mod order */
        if (!tmp)
            tmp = BN_CTX_get(ctx);
        if (!tmp2)
            tmp2 = BN_CTX_get(ctx);
        if (!s)
            s = BN_CTX_get(ctx);
        if (!tmp || !tmp2 || !s) {
            GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
            goto err;
        }

        if (!BN_mod_mul(tmp, priv_key, r, order, ctx)
            || !BN_mod_mul(tmp2, k, e, order, ctx)
            || !BN_mod_add(s, tmp, tmp2, order, ctx)) {
            GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
            goto err;
        }
    }
    while (BN_is_zero(s));

    newsig->s = BN_dup(s);
    newsig->r = BN_dup(r);
    if (!newsig->s || !newsig->r) {
        GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    ret = newsig;
 err:
    BN_CTX_end(ctx);
    BN_CTX_free(ctx);
    if (C)
        EC_POINT_free(C);
    if (md)
        BN_free(md);
    if (!ret && newsig) {
        DSA_SIG_free(newsig);
    }
    return ret;
}