Esempio n. 1
0
static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
	const struct rsa_asn1_template *digest_info;
	unsigned int pos;

	if (err == -EOVERFLOW)
		/* Decrypted value had no leading 0 byte */
		err = -EINVAL;

	if (err)
		goto done;

	if (req_ctx->child_req.dst_len != ctx->key_size - 1) {
		err = -EINVAL;
		goto done;
	}

	err = -EBADMSG;
	if (req_ctx->out_buf[0] != 0x01)
		goto done;

	for (pos = 1; pos < req_ctx->child_req.dst_len; pos++)
		if (req_ctx->out_buf[pos] != 0xff)
			break;

	if (pos < 9 || pos == req_ctx->child_req.dst_len ||
	    req_ctx->out_buf[pos] != 0x00)
		goto done;
	pos++;

	if (ctx->hash_name) {
		digest_info = rsa_lookup_asn1(ctx->hash_name);
		if (!digest_info)
			goto done;

		if (memcmp(req_ctx->out_buf + pos, digest_info->data,
			   digest_info->size))
			goto done;

		pos += digest_info->size;
	}

	err = 0;

	if (req->dst_len < req_ctx->child_req.dst_len - pos)
		err = -EOVERFLOW;
	req->dst_len = req_ctx->child_req.dst_len - pos;

	if (!err)
		sg_copy_from_buffer(req->dst,
				sg_nents_for_len(req->dst, req->dst_len),
				req_ctx->out_buf + pos, req->dst_len);
done:
	kzfree(req_ctx->out_buf);

	return err;
}
Esempio n. 2
0
static int pkcs1pad_sign(struct akcipher_request *req)
{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
	const struct rsa_asn1_template *digest_info = NULL;
	int err;
	unsigned int ps_end, digest_size = 0;

	if (!ctx->key_size)
		return -EINVAL;

	if (ctx->hash_name) {
		digest_info = rsa_lookup_asn1(ctx->hash_name);
		if (!digest_info)
			return -EINVAL;

		digest_size = digest_info->size;
	}

	if (req->src_len + digest_size > ctx->key_size - 11)
		return -EOVERFLOW;

	if (req->dst_len < ctx->key_size) {
		req->dst_len = ctx->key_size;
		return -EOVERFLOW;
	}

	if (ctx->key_size > PAGE_SIZE)
		return -ENOTSUPP;

	/*
	 * Replace both input and output to add the padding in the input and
	 * the potential missing leading zeros in the output.
	 */
	req_ctx->child_req.src = req_ctx->in_sg;
	req_ctx->child_req.src_len = ctx->key_size - 1;
	req_ctx->child_req.dst = req_ctx->out_sg;
	req_ctx->child_req.dst_len = ctx->key_size;

	req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
			(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
			GFP_KERNEL : GFP_ATOMIC);
	if (!req_ctx->in_buf)
		return -ENOMEM;

	ps_end = ctx->key_size - digest_size - req->src_len - 2;
	req_ctx->in_buf[0] = 0x01;
	memset(req_ctx->in_buf + 1, 0xff, ps_end - 1);
	req_ctx->in_buf[ps_end] = 0x00;

	if (digest_info) {
		memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data,
		       digest_info->size);
	}

	pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
			ctx->key_size - 1 - req->src_len, req->src);

	req_ctx->out_buf = kmalloc(ctx->key_size,
			(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
			GFP_KERNEL : GFP_ATOMIC);
	if (!req_ctx->out_buf) {
		kfree(req_ctx->in_buf);
		return -ENOMEM;
	}

	pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
			ctx->key_size, NULL);

	akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
	akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
			pkcs1pad_encrypt_sign_complete_cb, req);

	err = crypto_akcipher_sign(&req_ctx->child_req);
	if (err != -EINPROGRESS &&
			(err != -EBUSY ||
			 !(req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)))
		return pkcs1pad_encrypt_sign_complete(req, err);

	return err;
}
Esempio n. 3
0
static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
{
	const struct rsa_asn1_template *digest_info;
	struct crypto_attr_type *algt;
	struct akcipher_instance *inst;
	struct pkcs1pad_inst_ctx *ctx;
	struct crypto_akcipher_spawn *spawn;
	struct akcipher_alg *rsa_alg;
	const char *rsa_alg_name;
	const char *hash_name;
	int err;

	algt = crypto_get_attr_type(tb);
	if (IS_ERR(algt))
		return PTR_ERR(algt);

	if ((algt->type ^ CRYPTO_ALG_TYPE_AKCIPHER) & algt->mask)
		return -EINVAL;

	rsa_alg_name = crypto_attr_alg_name(tb[1]);
	if (IS_ERR(rsa_alg_name))
		return PTR_ERR(rsa_alg_name);

	hash_name = crypto_attr_alg_name(tb[2]);
	if (IS_ERR(hash_name))
		hash_name = NULL;

	if (hash_name) {
		digest_info = rsa_lookup_asn1(hash_name);
		if (!digest_info)
			return -EINVAL;
	} else
		digest_info = NULL;

	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
	if (!inst)
		return -ENOMEM;

	ctx = akcipher_instance_ctx(inst);
	spawn = &ctx->spawn;
	ctx->digest_info = digest_info;

	crypto_set_spawn(&spawn->base, akcipher_crypto_instance(inst));
	err = crypto_grab_akcipher(spawn, rsa_alg_name, 0,
			crypto_requires_sync(algt->type, algt->mask));
	if (err)
		goto out_free_inst;

	rsa_alg = crypto_spawn_akcipher_alg(spawn);

	err = -ENAMETOOLONG;

	if (!hash_name) {
		if (snprintf(inst->alg.base.cra_name,
			     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
			     rsa_alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
			goto out_drop_alg;

		if (snprintf(inst->alg.base.cra_driver_name,
			     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
			     rsa_alg->base.cra_driver_name) >=
			     CRYPTO_MAX_ALG_NAME)
			goto out_drop_alg;
	} else {
		if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
			     "pkcs1pad(%s,%s)", rsa_alg->base.cra_name,
			     hash_name) >= CRYPTO_MAX_ALG_NAME)
			goto out_drop_alg;

		if (snprintf(inst->alg.base.cra_driver_name,
			     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s,%s)",
			     rsa_alg->base.cra_driver_name,
			     hash_name) >= CRYPTO_MAX_ALG_NAME)
			goto out_drop_alg;
	}

	inst->alg.base.cra_flags = rsa_alg->base.cra_flags & CRYPTO_ALG_ASYNC;
	inst->alg.base.cra_priority = rsa_alg->base.cra_priority;
	inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx);

	inst->alg.init = pkcs1pad_init_tfm;
	inst->alg.exit = pkcs1pad_exit_tfm;

	inst->alg.encrypt = pkcs1pad_encrypt;
	inst->alg.decrypt = pkcs1pad_decrypt;
	inst->alg.sign = pkcs1pad_sign;
	inst->alg.verify = pkcs1pad_verify;
	inst->alg.set_pub_key = pkcs1pad_set_pub_key;
	inst->alg.set_priv_key = pkcs1pad_set_priv_key;
	inst->alg.max_size = pkcs1pad_get_max_size;
	inst->alg.reqsize = sizeof(struct pkcs1pad_request) + rsa_alg->reqsize;

	inst->free = pkcs1pad_free;

	err = akcipher_register_instance(tmpl, inst);
	if (err)
		goto out_drop_alg;

	return 0;

out_drop_alg:
	crypto_drop_akcipher(spawn);
out_free_inst:
	kfree(inst);
	return err;
}