eng_cryptodev.c

OpenSSL 0.9.8k 最新版OpenSSL

 * a particular NID in the ENGINE. this says what we'll do at the
 * top level - note, that list is restricted by what we answer with
 */
static int
cryptodev_engine_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
    const int **nids, int nid)
{
	if (!cipher)
		return (cryptodev_usable_ciphers(nids));

	switch (nid) {
	case NID_des_ede3_cbc:
		*cipher = &cryptodev_3des_cbc;
		break;
	case NID_des_cbc:
		*cipher = &cryptodev_des_cbc;
		break;
	case NID_bf_cbc:
		*cipher = &cryptodev_bf_cbc;
		break;
	case NID_cast5_cbc:
		*cipher = &cryptodev_cast_cbc;
		break;
	case NID_aes_128_cbc:
		*cipher = &cryptodev_aes_cbc;
		break;
	default:
		*cipher = NULL;
		break;
	}
	return (*cipher != NULL);
}

static int
cryptodev_engine_digests(ENGINE *e, const EVP_MD **digest,
    const int **nids, int nid)
{
	if (!digest)
		return (cryptodev_usable_digests(nids));

	switch (nid) {
	case NID_md5:
		*digest = NULL; /* need to make a clean md5 critter */
		break;
	default:
		*digest = NULL;
		break;
	}
	return (*digest != NULL);
}

/*
 * Convert a BIGNUM to the representation that /dev/crypto needs.
 * Upon completion of use, the caller is responsible for freeing
 * crp->crp_p.
 */
static int
bn2crparam(const BIGNUM *a, struct crparam *crp)
{
	int i, j, k;
	ssize_t words, bytes, bits;
	u_char *b;

	crp->crp_p = NULL;
	crp->crp_nbits = 0;

	bits = BN_num_bits(a);
	bytes = (bits + 7) / 8;

	b = malloc(bytes);
	if (b == NULL)
		return (1);

	crp->crp_p = b;
	crp->crp_nbits = bits;

	for (i = 0, j = 0; i < a->top; i++) {
		for (k = 0; k < BN_BITS2 / 8; k++) {
			if ((j + k) >= bytes)
				return (0);
			b[j + k] = a->d[i] >> (k * 8);
		}
		j += BN_BITS2 / 8;
	}
	return (0);
}

/* Convert a /dev/crypto parameter to a BIGNUM */
static int
crparam2bn(struct crparam *crp, BIGNUM *a)
{
	u_int8_t *pd;
	int i, bytes;

	bytes = (crp->crp_nbits + 7) / 8;

	if (bytes == 0)
		return (-1);

	if ((pd = (u_int8_t *) malloc(bytes)) == NULL)
		return (-1);

	for (i = 0; i < bytes; i++)
		pd[i] = crp->crp_p[bytes - i - 1];

	BN_bin2bn(pd, bytes, a);
	free(pd);

	return (0);
}

static void
zapparams(struct crypt_kop *kop)
{
	int i;

	for (i = 0; i <= kop->crk_iparams + kop->crk_oparams; i++) {
		if (kop->crk_param[i].crp_p)
			free(kop->crk_param[i].crp_p);
		kop->crk_param[i].crp_p = NULL;
		kop->crk_param[i].crp_nbits = 0;
	}
}

static int
cryptodev_asym(struct crypt_kop *kop, int rlen, BIGNUM *r, int slen, BIGNUM *s)
{
	int fd, ret = -1;

	if ((fd = get_asym_dev_crypto()) < 0)
		return (ret);

	if (r) {
		kop->crk_param[kop->crk_iparams].crp_p = calloc(rlen, sizeof(char));
		kop->crk_param[kop->crk_iparams].crp_nbits = rlen * 8;
		kop->crk_oparams++;
	}
	if (s) {
		kop->crk_param[kop->crk_iparams+1].crp_p = calloc(slen, sizeof(char));
		kop->crk_param[kop->crk_iparams+1].crp_nbits = slen * 8;
		kop->crk_oparams++;
	}

	if (ioctl(fd, CIOCKEY, kop) == 0) {
		if (r)
			crparam2bn(&kop->crk_param[kop->crk_iparams], r);
		if (s)
			crparam2bn(&kop->crk_param[kop->crk_iparams+1], s);
		ret = 0;
	}

	return (ret);
}

static int
cryptodev_bn_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
    const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
{
	struct crypt_kop kop;
	int ret = 1;

	/* Currently, we know we can do mod exp iff we can do any
	 * asymmetric operations at all.
	 */
	if (cryptodev_asymfeat == 0) {
		ret = BN_mod_exp(r, a, p, m, ctx);
		return (ret);
	}

	memset(&kop, 0, sizeof kop);
	kop.crk_op = CRK_MOD_EXP;

	/* inputs: a^p % m */
	if (bn2crparam(a, &kop.crk_param[0]))
		goto err;
	if (bn2crparam(p, &kop.crk_param[1]))
		goto err;
	if (bn2crparam(m, &kop.crk_param[2]))
		goto err;
	kop.crk_iparams = 3;

	if (cryptodev_asym(&kop, BN_num_bytes(m), r, 0, NULL) == -1) {
		const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
		ret = meth->bn_mod_exp(r, a, p, m, ctx, in_mont);
	}
err:
	zapparams(&kop);
	return (ret);
}

static int
cryptodev_rsa_nocrt_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
{
	int r;
	BN_CTX *ctx;

	ctx = BN_CTX_new();
	r = cryptodev_bn_mod_exp(r0, I, rsa->d, rsa->n, ctx, NULL);
	BN_CTX_free(ctx);
	return (r);
}

static int
cryptodev_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
	struct crypt_kop kop;
	int ret = 1;

	if (!rsa->p || !rsa->q || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp) {
		/* XXX 0 means failure?? */
		return (0);
	}

	memset(&kop, 0, sizeof kop);
	kop.crk_op = CRK_MOD_EXP_CRT;
	/* inputs: rsa->p rsa->q I rsa->dmp1 rsa->dmq1 rsa->iqmp */
	if (bn2crparam(rsa->p, &kop.crk_param[0]))
		goto err;
	if (bn2crparam(rsa->q, &kop.crk_param[1]))
		goto err;
	if (bn2crparam(I, &kop.crk_param[2]))
		goto err;
	if (bn2crparam(rsa->dmp1, &kop.crk_param[3]))
		goto err;
	if (bn2crparam(rsa->dmq1, &kop.crk_param[4]))
		goto err;
	if (bn2crparam(rsa->iqmp, &kop.crk_param[5]))
		goto err;
	kop.crk_iparams = 6;

	if (cryptodev_asym(&kop, BN_num_bytes(rsa->n), r0, 0, NULL) == -1) {
		const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
		ret = (*meth->rsa_mod_exp)(r0, I, rsa, ctx);
	}
err:
	zapparams(&kop);
	return (ret);
}

static RSA_METHOD cryptodev_rsa = {
	"cryptodev RSA method",
	NULL,				/* rsa_pub_enc */
	NULL,				/* rsa_pub_dec */
	NULL,				/* rsa_priv_enc */
	NULL,				/* rsa_priv_dec */
	NULL,
	NULL,
	NULL,				/* init */
	NULL,				/* finish */
	0,				/* flags */
	NULL,				/* app_data */
	NULL,				/* rsa_sign */
	NULL				/* rsa_verify */
};

static int
cryptodev_dsa_bn_mod_exp(DSA *dsa, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
    const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx)
{
	return (cryptodev_bn_mod_exp(r, a, p, m, ctx, m_ctx));
}

static int
cryptodev_dsa_dsa_mod_exp(DSA *dsa, BIGNUM *t1, BIGNUM *g,
    BIGNUM *u1, BIGNUM *pub_key, BIGNUM *u2, BIGNUM *p,
    BN_CTX *ctx, BN_MONT_CTX *mont)
{
	BIGNUM t2;
	int ret = 0;

	BN_init(&t2);

	/* v = ( g^u1 * y^u2 mod p ) mod q */
	/* let t1 = g ^ u1 mod p */
	ret = 0;

	if (!dsa->meth->bn_mod_exp(dsa,t1,dsa->g,u1,dsa->p,ctx,mont))
		goto err;

	/* let t2 = y ^ u2 mod p */
	if (!dsa->meth->bn_mod_exp(dsa,&t2,dsa->pub_key,u2,dsa->p,ctx,mont))
		goto err;
	/* let u1 = t1 * t2 mod p */
	if (!BN_mod_mul(u1,t1,&t2,dsa->p,ctx))
		goto err;

	BN_copy(t1,u1);

	ret = 1;
err:
	BN_free(&t2);
	return(ret);
}

static DSA_SIG *
cryptodev_dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
{
	struct crypt_kop kop;
	BIGNUM *r = NULL, *s = NULL;
	DSA_SIG *dsaret = NULL;

	if ((r = BN_new()) == NULL)
		goto err;
	if ((s = BN_new()) == NULL) {
		BN_free(r);
		goto err;
	}

	memset(&kop, 0, sizeof kop);
	kop.crk_op = CRK_DSA_SIGN;

	/* inputs: dgst dsa->p dsa->q dsa->g dsa->priv_key */
	kop.crk_param[0].crp_p = (caddr_t)dgst;
	kop.crk_param[0].crp_nbits = dlen * 8;
	if (bn2crparam(dsa->p, &kop.crk_param[1]))
		goto err;
	if (bn2crparam(dsa->q, &kop.crk_param[2]))
		goto err;
	if (bn2crparam(dsa->g, &kop.crk_param[3]))
		goto err;
	if (bn2crparam(dsa->priv_key, &kop.crk_param[4]))
		goto err;
	kop.crk_iparams = 5;

	if (cryptodev_asym(&kop, BN_num_bytes(dsa->q), r,
	    BN_num_bytes(dsa->q), s) == 0) {
		dsaret = DSA_SIG_new();
		dsaret->r = r;
		dsaret->s = s;
	} else {
		const DSA_METHOD *meth = DSA_OpenSSL();
		BN_free(r);
		BN_free(s);
		dsaret = (meth->dsa_do_sign)(dgst, dlen, dsa);
	}
err:
	kop.crk_param[0].crp_p = NULL;
	zapparams(&kop);
	return (dsaret);
}

static int
cryptodev_dsa_verify(const unsigned char *dgst, int dlen,
    DSA_SIG *sig, DSA *dsa)
{
	struct crypt_kop kop;
	int dsaret = 1;

	memset(&kop, 0, sizeof kop);
	kop.crk_op = CRK_DSA_VERIFY;

	/* inputs: dgst dsa->p dsa->q dsa->g dsa->pub_key sig->r sig->s */
	kop.crk_param[0].crp_p = (caddr_t)dgst;
	kop.crk_param[0].crp_nbits = dlen * 8;
	if (bn2crparam(dsa->p, &kop.crk_param[1]))
		goto err;
	if (bn2crparam(dsa->q, &kop.crk_param[2]))
		goto err;
	if (bn2crparam(dsa->g, &kop.crk_param[3]))
		goto err;
	if (bn2crparam(dsa->pub_key, &kop.crk_param[4]))
		goto err;
	if (bn2crparam(sig->r, &kop.crk_param[5]))
		goto err;
	if (bn2crparam(sig->s, &kop.crk_param[6]))
		goto err;
	kop.crk_iparams = 7;

	if (cryptodev_asym(&kop, 0, NULL, 0, NULL) == 0) {
		dsaret = kop.crk_status;
	} else {
		const DSA_METHOD *meth = DSA_OpenSSL();

		dsaret = (meth->dsa_do_verify)(dgst, dlen, sig, dsa);
	}
err:
	kop.crk_param[0].crp_p = NULL;
	zapparams(&kop);
	return (dsaret);
}

static DSA_METHOD cryptodev_dsa = {
	"cryptodev DSA method",
	NULL,
	NULL,				/* dsa_sign_setup */
	NULL,
	NULL,				/* dsa_mod_exp */
	NULL,
	NULL,				/* init */
	NULL,				/* finish */
	0,	/* flags */
	NULL	/* app_data */
};

static int
cryptodev_mod_exp_dh(const DH *dh, BIGNUM *r, const BIGNUM *a,
    const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx,
    BN_MONT_CTX *m_ctx)
{
	return (cryptodev_bn_mod_exp(r, a, p, m, ctx, m_ctx));
}

static int
cryptodev_dh_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
	struct crypt_kop kop;
	int dhret = 1;
	int fd, keylen;

	if ((fd = get_asym_dev_crypto()) < 0) {
		const DH_METHOD *meth = DH_OpenSSL();

		return ((meth->compute_key)(key, pub_key, dh));
	}

	keylen = BN_num_bits(dh->p);

	memset(&kop, 0, sizeof kop);
	kop.crk_op = CRK_DH_COMPUTE_KEY;

	/* inputs: dh->priv_key pub_key dh->p key */
	if (bn2crparam(dh->priv_key, &kop.crk_param[0]))
		goto err;
	if (bn2crparam(pub_key, &kop.crk_param[1]))
		goto err;
	if (bn2crparam(dh->p, &kop.crk_param[2]))
		goto err;
	kop.crk_iparams = 3;

	kop.crk_param[3].crp_p = key;
	kop.crk_param[3].crp_nbits = keylen * 8;
	kop.crk_oparams = 1;

	if (ioctl(fd, CIOCKEY, &kop) == -1) {
		const DH_METHOD *meth = DH_OpenSSL();

		dhret = (meth->compute_key)(key, pub_key, dh);
	}
err:
	kop.crk_param[3].crp_p = NULL;
	zapparams(&kop);
	return (dhret);
}

static DH_METHOD cryptodev_dh = {
	"cryptodev DH method",
	NULL,				/* cryptodev_dh_generate_key */
	NULL,
	NULL,
	NULL,
	NULL,
	0,	/* flags */
	NULL	/* app_data */
};

/*
 * ctrl right now is just a wrapper that doesn't do much
 * but I expect we'll want some options soon.
 */
static int
cryptodev_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)())
{
#ifdef HAVE_SYSLOG_R
	struct syslog_data sd = SYSLOG_DATA_INIT;
#endif

	switch (cmd) {
	default:
#ifdef HAVE_SYSLOG_R
		syslog_r(LOG_ERR, &sd,
		    "cryptodev_ctrl: unknown command %d", cmd);
#else
		syslog(LOG_ERR, "cryptodev_ctrl: unknown command %d", cmd);
#endif
		break;
	}
	return (1);
}

void
ENGINE_load_cryptodev(void)
{
	ENGINE *engine = ENGINE_new();
	int fd;

	if (engine == NULL)
		return;
	if ((fd = get_dev_crypto()) < 0) {
		ENGINE_free(engine);
		return;
	}

	/*
	 * find out what asymmetric crypto algorithms we support
	 */
	if (ioctl(fd, CIOCASYMFEAT, &cryptodev_asymfeat) == -1) {
		close(fd);
		ENGINE_free(engine);
		return;
	}
	close(fd);

	if (!ENGINE_set_id(engine, "cryptodev") ||
	    !ENGINE_set_name(engine, "BSD cryptodev engine") ||
	    !ENGINE_set_ciphers(engine, cryptodev_engine_ciphers) ||
	    !ENGINE_set_digests(engine, cryptodev_engine_digests) ||
	    !ENGINE_set_ctrl_function(engine, cryptodev_ctrl) ||
	    !ENGINE_set_cmd_defns(engine, cryptodev_defns)) {
		ENGINE_free(engine);
		return;
	}

	if (ENGINE_set_RSA(engine, &cryptodev_rsa)) {
		const RSA_METHOD *rsa_meth = RSA_PKCS1_SSLeay();

		cryptodev_rsa.bn_mod_exp = rsa_meth->bn_mod_exp;
		cryptodev_rsa.rsa_mod_exp = rsa_meth->rsa_mod_exp;
		cryptodev_rsa.rsa_pub_enc = rsa_meth->rsa_pub_enc;
		cryptodev_rsa.rsa_pub_dec = rsa_meth->rsa_pub_dec;
		cryptodev_rsa.rsa_priv_enc = rsa_meth->rsa_priv_enc;
		cryptodev_rsa.rsa_priv_dec = rsa_meth->rsa_priv_dec;
		if (cryptodev_asymfeat & CRF_MOD_EXP) {
			cryptodev_rsa.bn_mod_exp = cryptodev_bn_mod_exp;
			if (cryptodev_asymfeat & CRF_MOD_EXP_CRT)
				cryptodev_rsa.rsa_mod_exp =
				    cryptodev_rsa_mod_exp;
			else
				cryptodev_rsa.rsa_mod_exp =
				    cryptodev_rsa_nocrt_mod_exp;
		}
	}

	if (ENGINE_set_DSA(engine, &cryptodev_dsa)) {
		const DSA_METHOD *meth = DSA_OpenSSL();

		memcpy(&cryptodev_dsa, meth, sizeof(DSA_METHOD));
		if (cryptodev_asymfeat & CRF_DSA_SIGN)
			cryptodev_dsa.dsa_do_sign = cryptodev_dsa_do_sign;
		if (cryptodev_asymfeat & CRF_MOD_EXP) {
			cryptodev_dsa.bn_mod_exp = cryptodev_dsa_bn_mod_exp;
			cryptodev_dsa.dsa_mod_exp = cryptodev_dsa_dsa_mod_exp;
		}
		if (cryptodev_asymfeat & CRF_DSA_VERIFY)
			cryptodev_dsa.dsa_do_verify = cryptodev_dsa_verify;
	}

	if (ENGINE_set_DH(engine, &cryptodev_dh)){
		const DH_METHOD *dh_meth = DH_OpenSSL();

		cryptodev_dh.generate_key = dh_meth->generate_key;
		cryptodev_dh.compute_key = dh_meth->compute_key;
		cryptodev_dh.bn_mod_exp = dh_meth->bn_mod_exp;
		if (cryptodev_asymfeat & CRF_MOD_EXP) {
			cryptodev_dh.bn_mod_exp = cryptodev_mod_exp_dh;
			if (cryptodev_asymfeat & CRF_DH_COMPUTE_KEY)
				cryptodev_dh.compute_key =
				    cryptodev_dh_compute_key;
		}
	}

	ENGINE_add(engine);
	ENGINE_free(engine);
	ERR_clear_error();
}

#endif /* HAVE_CRYPTODEV */