/*
* The verify operation is here for completeness similar to the verification
* defined in RFC2313 section 10.2 except that block type 0 is not accepted,
* as in RFC2437. RFC2437 section 9.2 doesn't define any operation to
* retrieve the DigestInfo from a signature, instead the user is expected
* to call the sign operation to generate the expected signature and compare
* signatures instead of the message-digests.
*/
static int pkcs1pad_verify(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);
int err;
if (!ctx->key_size || req->src_len < ctx->key_size)
return -EINVAL;
req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
if (!req_ctx->out_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_verify_complete_cb, req);
/* Reuse input buffer, output to a new buffer */
akcipher_request_set_crypt(&req_ctx->child_req, req->src,
req_ctx->out_sg, req->src_len,
ctx->key_size);
err = crypto_akcipher_verify(&req_ctx->child_req);
if (err != -EINPROGRESS && err != -EBUSY)
return pkcs1pad_verify_complete(req, err);
return err;
}
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);
struct akcipher_instance *inst = akcipher_alg_instance(tfm);
struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
const struct rsa_asn1_template *digest_info = ictx->digest_info;
int err;
unsigned int ps_end, digest_size = 0;
if (!ctx->key_size)
return -EINVAL;
if (digest_info)
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;
}
req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
GFP_KERNEL);
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);
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);
/* Reuse output buffer */
akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
req->dst, ctx->key_size - 1, req->dst_len);
err = crypto_akcipher_sign(&req_ctx->child_req);
if (err != -EINPROGRESS && err != -EBUSY)
return pkcs1pad_encrypt_sign_complete(req, err);
return err;
}
/*
* Encryption operation is performed with the public key. Hence it is done
* in software
*/
static int tpm_key_encrypt(struct tpm_key *tk,
struct kernel_pkey_params *params,
const void *in, void *out)
{
char alg_name[CRYPTO_MAX_ALG_NAME];
struct crypto_akcipher *tfm;
struct akcipher_request *req;
struct crypto_wait cwait;
struct scatterlist in_sg, out_sg;
uint8_t der_pub_key[PUB_KEY_BUF_SIZE];
uint32_t der_pub_key_len;
int ret;
pr_devel("==>%s()\n", __func__);
ret = determine_akcipher(params->encoding, params->hash_algo, alg_name);
if (ret < 0)
return ret;
tfm = crypto_alloc_akcipher(alg_name, 0, 0);
if (IS_ERR(tfm))
return PTR_ERR(tfm);
der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len,
der_pub_key);
ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len);
if (ret < 0)
goto error_free_tfm;
req = akcipher_request_alloc(tfm, GFP_KERNEL);
if (!req)
goto error_free_tfm;
sg_init_one(&in_sg, in, params->in_len);
sg_init_one(&out_sg, out, params->out_len);
akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len,
params->out_len);
crypto_init_wait(&cwait);
akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
CRYPTO_TFM_REQ_MAY_SLEEP,
crypto_req_done, &cwait);
ret = crypto_akcipher_encrypt(req);
ret = crypto_wait_req(ret, &cwait);
if (ret == 0)
ret = req->dst_len;
akcipher_request_free(req);
error_free_tfm:
crypto_free_akcipher(tfm);
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
}
static int pkcs1pad_encrypt(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);
int err;
unsigned int i, ps_end;
if (!ctx->key_size)
return -EINVAL;
if (req->src_len > ctx->key_size - 11)
return -EOVERFLOW;
if (req->dst_len < ctx->key_size) {
req->dst_len = ctx->key_size;
return -EOVERFLOW;
}
req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
GFP_KERNEL);
if (!req_ctx->in_buf)
return -ENOMEM;
ps_end = ctx->key_size - req->src_len - 2;
req_ctx->in_buf[0] = 0x02;
for (i = 1; i < ps_end; i++)
req_ctx->in_buf[i] = 1 + prandom_u32_max(255);
req_ctx->in_buf[ps_end] = 0x00;
pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
ctx->key_size - 1 - req->src_len, req->src);
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);
/* Reuse output buffer */
akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
req->dst, ctx->key_size - 1, req->dst_len);
err = crypto_akcipher_encrypt(&req_ctx->child_req);
if (err != -EINPROGRESS && err != -EBUSY)
return pkcs1pad_encrypt_sign_complete(req, err);
return err;
}
/*
* The verify operation is here for completeness similar to the verification
* defined in RFC2313 section 10.2 except that block type 0 is not accepted,
* as in RFC2437. RFC2437 section 9.2 doesn't define any operation to
* retrieve the DigestInfo from a signature, instead the user is expected
* to call the sign operation to generate the expected signature and compare
* signatures instead of the message-digests.
*/
static int pkcs1pad_verify(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);
int err;
if (!ctx->key_size || req->src_len < ctx->key_size)
return -EINVAL;
if (ctx->key_size > PAGE_SIZE)
return -ENOTSUPP;
/* Reuse input buffer, output to a new buffer */
req_ctx->child_req.src = req->src;
req_ctx->child_req.src_len = req->src_len;
req_ctx->child_req.dst = req_ctx->out_sg;
req_ctx->child_req.dst_len = ctx->key_size - 1;
req_ctx->out_buf = kmalloc(ctx->key_size - 1,
(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
GFP_KERNEL : GFP_ATOMIC);
if (!req_ctx->out_buf)
return -ENOMEM;
pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
ctx->key_size - 1, NULL);
akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
pkcs1pad_verify_complete_cb, req);
err = crypto_akcipher_verify(&req_ctx->child_req);
if (err != -EINPROGRESS &&
(err != -EBUSY ||
!(req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)))
return pkcs1pad_verify_complete(req, err);
return err;
}
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;
}
static int pkcs1pad_encrypt(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);
int err;
unsigned int i, ps_end;
if (!ctx->key_size)
return -EINVAL;
if (req->src_len > 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 - req->src_len - 2;
req_ctx->in_buf[0] = 0x02;
for (i = 1; i < ps_end; i++)
req_ctx->in_buf[i] = 1 + prandom_u32_max(255);
req_ctx->in_buf[ps_end] = 0x00;
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_encrypt(&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;
}
/*
* Verify a signature using a public key.
*/
static int tpm_key_verify_signature(const struct key *key,
const struct public_key_signature *sig)
{
const struct tpm_key *tk = key->payload.data[asym_crypto];
struct crypto_wait cwait;
struct crypto_akcipher *tfm;
struct akcipher_request *req;
struct scatterlist sig_sg, digest_sg;
char alg_name[CRYPTO_MAX_ALG_NAME];
uint8_t der_pub_key[PUB_KEY_BUF_SIZE];
uint32_t der_pub_key_len;
void *output;
unsigned int outlen;
int ret;
pr_devel("==>%s()\n", __func__);
BUG_ON(!tk);
BUG_ON(!sig);
BUG_ON(!sig->s);
if (!sig->digest)
return -ENOPKG;
ret = determine_akcipher(sig->encoding, sig->hash_algo, alg_name);
if (ret < 0)
return ret;
tfm = crypto_alloc_akcipher(alg_name, 0, 0);
if (IS_ERR(tfm))
return PTR_ERR(tfm);
der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len,
der_pub_key);
ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len);
if (ret < 0)
goto error_free_tfm;
ret = -ENOMEM;
req = akcipher_request_alloc(tfm, GFP_KERNEL);
if (!req)
goto error_free_tfm;
ret = -ENOMEM;
outlen = crypto_akcipher_maxsize(tfm);
output = kmalloc(outlen, GFP_KERNEL);
if (!output)
goto error_free_req;
sg_init_one(&sig_sg, sig->s, sig->s_size);
sg_init_one(&digest_sg, output, outlen);
akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size,
outlen);
crypto_init_wait(&cwait);
akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
CRYPTO_TFM_REQ_MAY_SLEEP,
crypto_req_done, &cwait);
/* Perform the verification calculation. This doesn't actually do the
* verification, but rather calculates the hash expected by the
* signature and returns that to us.
*/
ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
if (ret)
goto out_free_output;
/* Do the actual verification step. */
if (req->dst_len != sig->digest_size ||
memcmp(sig->digest, output, sig->digest_size) != 0)
ret = -EKEYREJECTED;
out_free_output:
kfree(output);
error_free_req:
akcipher_request_free(req);
error_free_tfm:
crypto_free_akcipher(tfm);
pr_devel("<==%s() = %d\n", __func__, ret);
if (WARN_ON_ONCE(ret > 0))
ret = -EINVAL;
return ret;
}