API is reworked following suggestions of Herbert Xu.
Previous akcipher .verify() just `decrypts' (using RSA encrypt which is
using public key) signature to uncover message hash, which was then
compared in upper level public_key_verify_signature() with the expected
hash value, which itself was never passed into verify().
This approach was incompatible with EC-DSA family of algorithms,
because, to verify a signature EC-DSA algorithm also needs a hash value
as input; then it's used (together with a signature divided into halves
`r||s') to produce a witness value, which is then compared with `r' to
determine if the signature is correct. Thus, for EC-DSA, nor
requirements of .verify() itself, nor its output expectations in
public_key_verify_signature() wasn't sufficient.
Make improved .verify() call which gets a signature together with a hash
value as input and produce complete signature check without any output
besides status.
RSA backends should not have sign/verify callbacks defined (nor they
should be used directly). PKCS1 driver knows to call appropriate RSA
encrypt/decrypt callbacks to implement sign/verify.
Now for the top level verification only crypto_akcipher_verify() needs
to be called.
Tested on x86_64.
Signed-off-by: Vitaly Chikunov <vt@xxxxxxxxxxxx>
---
This should be applied over cryptodev tree.
Changes since v3:
- remove verify_rsa API from RSA backends.
- digest is appended to akcipher_request->src SG.
- pkcs1pad calls encrypt/decrypt for its backends instead of sign/verify.
- pkcs1pad now conform to the new verify API.
- make crypto_akcipher_{maxsize,sign,verify} more robust allowing
appropriate akcipher clllbacks to be undefined.
Changes since v2:
- `output` is factored out from public_key_verify_signature() into
crypto_akcipher_verify().
- in crypto_akcipher_verify_rsa() -ENOSYS error is added for robustness (if,
in the future, some RSA driver will not implement this api).
- api descriptions are updated to be more clear.
Changes since v1:
- complete rework to the different approach and should be treated as
a new patch.
crypto/asymmetric_keys/asym_tpm.c | 32 ++------
crypto/asymmetric_keys/public_key.c | 33 ++------
crypto/rsa-pkcs1pad.c | 31 +++++---
crypto/rsa.c | 109 --------------------------
crypto/testmgr.c | 47 ++++++-----
drivers/crypto/caam/caampkc.c | 2 -
drivers/crypto/ccp/ccp-crypto-rsa.c | 2 -
drivers/crypto/qat/qat_common/qat_asym_algs.c | 2 -
include/crypto/akcipher.h | 53 +++++++++----
9 files changed, 94 insertions(+), 217 deletions(-)
diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c
index 5d4c270463f6..eef548319877 100644
--- a/crypto/asymmetric_keys/asym_tpm.c
+++ b/crypto/asymmetric_keys/asym_tpm.c
@@ -744,11 +744,10 @@ static int tpm_key_verify_signature(const struct key *key,
struct crypto_wait cwait;
struct crypto_akcipher *tfm;
struct akcipher_request *req;
- struct scatterlist sig_sg, digest_sg;
+ struct scatterlist src_sg[2];
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;
@@ -781,36 +780,17 @@ static int tpm_key_verify_signature(const struct key *key,
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);
+ sg_init_table(&src_sg, 2);
+ sg_set_buf(&src_sg[0], sig->s, sig->s_size);
+ sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
+ akcipher_request_set_crypt(req, &src_sg, NULL, sig->s_size,
+ sig->digest_size);
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:
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index f5d85b47fcc6..33093b7bcc47 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -227,10 +227,8 @@ int public_key_verify_signature(const struct public_key *pkey,
struct crypto_wait cwait;
struct crypto_akcipher *tfm;
struct akcipher_request *req;
- struct scatterlist sig_sg, digest_sg;
+ struct scatterlist src_sg[2];
char alg_name[CRYPTO_MAX_ALG_NAME];
- void *output;
- unsigned int outlen;
int ret;
pr_devel("==>%s()\n", __func__);
@@ -263,36 +261,17 @@ int public_key_verify_signature(const struct public_key *pkey,
if (ret)
goto error_free_req;
- 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);
+ sg_init_table(src_sg, 2);
+ sg_set_buf(&src_sg[0], sig->s, sig->s_size);
+ sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
+ akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
+ sig->digest_size);
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:
diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c
index 0a6680ca8cb6..489bda6acf08 100644
--- a/crypto/rsa-pkcs1pad.c
+++ b/crypto/rsa-pkcs1pad.c
@@ -429,7 +429,7 @@ static int pkcs1pad_sign(struct akcipher_request *req)
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);
+ err = crypto_akcipher_decrypt(&req_ctx->child_req);
if (err != -EINPROGRESS && err != -EBUSY)
return pkcs1pad_encrypt_sign_complete(req, err);
@@ -488,14 +488,20 @@ static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
err = 0;
- if (req->dst_len < dst_len - pos)
- err = -EOVERFLOW;
- req->dst_len = dst_len - pos;
-
- if (!err)
- sg_copy_from_buffer(req->dst,
- sg_nents_for_len(req->dst, req->dst_len),
- out_buf + pos, req->dst_len);
+ if (req->dst_len != dst_len - pos) {
+ err = -EKEYREJECTED;
+ req->dst_len = dst_len - pos;
+ goto done;
+ }
+ /* Extract appended digest. */
+ sg_pcopy_to_buffer(req->src,
+ sg_nents_for_len(req->src,
+ req->src_len + req->dst_len),
+ req_ctx->out_buf + ctx->key_size,
+ req->dst_len, ctx->key_size);
+ /* Do the actual verification step. */
+ if (memcmp(req_ctx->out_buf + ctx->key_size, out_buf + pos, req->dst_len))
+ err = -EKEYREJECTED;
done:
kzfree(req_ctx->out_buf);
@@ -532,10 +538,11 @@ static int pkcs1pad_verify(struct akcipher_request *req)
struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
int err;
- if (!ctx->key_size || req->src_len < ctx->key_size)
+ if (req->dst || !req->dst_len ||
+ !ctx->key_size || req->src_len < ctx->key_size)
return -EINVAL;
- req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
+ req_ctx->out_buf = kmalloc(ctx->key_size + req->dst_len, GFP_KERNEL);
if (!req_ctx->out_buf)
return -ENOMEM;
@@ -551,7 +558,7 @@ static int pkcs1pad_verify(struct akcipher_request *req)
req_ctx->out_sg, req->src_len,
ctx->key_size);
- err = crypto_akcipher_verify(&req_ctx->child_req);
+ err = crypto_akcipher_encrypt(&req_ctx->child_req);
if (err != -EINPROGRESS && err != -EBUSY)
return pkcs1pad_verify_complete(req, err);
diff --git a/crypto/rsa.c b/crypto/rsa.c
index 4167980c243d..5d427c1100d6 100644
--- a/crypto/rsa.c
+++ b/crypto/rsa.c
@@ -50,34 +50,6 @@ static int _rsa_dec(const struct rsa_mpi_key *key, MPI m, MPI c)
return mpi_powm(m, c, key->d, key->n);
}
-/*
- * RSASP1 function [RFC3447 sec 5.2.1]
- * s = m^d mod n
- */
-static int _rsa_sign(const struct rsa_mpi_key *key, MPI s, MPI m)
-{
- /* (1) Validate 0 <= m < n */
- if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0)
- return -EINVAL;
-
- /* (2) s = m^d mod n */
- return mpi_powm(s, m, key->d, key->n);
-}
-
-/*
- * RSAVP1 function [RFC3447 sec 5.2.2]
- * m = s^e mod n;
- */
-static int _rsa_verify(const struct rsa_mpi_key *key, MPI m, MPI s)
-{
- /* (1) Validate 0 <= s < n */
- if (mpi_cmp_ui(s, 0) < 0 || mpi_cmp(s, key->n) >= 0)
- return -EINVAL;
-
- /* (2) m = s^e mod n */
- return mpi_powm(m, s, key->e, key->n);
-}
-
static inline struct rsa_mpi_key *rsa_get_key(struct crypto_akcipher *tfm)
{
return akcipher_tfm_ctx(tfm);
@@ -160,85 +132,6 @@ static int rsa_dec(struct akcipher_request *req)
return ret;
}
-static int rsa_sign(struct akcipher_request *req)
-{
- struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
- const struct rsa_mpi_key *pkey = rsa_get_key(tfm);
- MPI m, s = mpi_alloc(0);
- int ret = 0;
- int sign;
-
- if (!s)
- return -ENOMEM;
-
- if (unlikely(!pkey->n || !pkey->d)) {
- ret = -EINVAL;
- goto err_free_s;
- }
-
- ret = -ENOMEM;
- m = mpi_read_raw_from_sgl(req->src, req->src_len);
- if (!m)
- goto err_free_s;
-
- ret = _rsa_sign(pkey, s, m);
- if (ret)
- goto err_free_m;
-
- ret = mpi_write_to_sgl(s, req->dst, req->dst_len, &sign);
- if (ret)
- goto err_free_m;
-
- if (sign < 0)
- ret = -EBADMSG;
-
-err_free_m:
- mpi_free(m);
-err_free_s:
- mpi_free(s);
- return ret;
-}
-
-static int rsa_verify(struct akcipher_request *req)
-{
- struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
- const struct rsa_mpi_key *pkey = rsa_get_key(tfm);
- MPI s, m = mpi_alloc(0);
- int ret = 0;
- int sign;
-
- if (!m)
- return -ENOMEM;
-
- if (unlikely(!pkey->n || !pkey->e)) {
- ret = -EINVAL;
- goto err_free_m;
- }
-
- s = mpi_read_raw_from_sgl(req->src, req->src_len);
- if (!s) {
- ret = -ENOMEM;
- goto err_free_m;
- }
-
- ret = _rsa_verify(pkey, m, s);
- if (ret)
- goto err_free_s;
-
- ret = mpi_write_to_sgl(m, req->dst, req->dst_len, &sign);
- if (ret)
- goto err_free_s;
-
- if (sign < 0)
- ret = -EBADMSG;
-
-err_free_s:
- mpi_free(s);
-err_free_m:
- mpi_free(m);
- return ret;
-}
-
static void rsa_free_mpi_key(struct rsa_mpi_key *key)
{
mpi_free(key->d);
@@ -353,8 +246,6 @@ static void rsa_exit_tfm(struct crypto_akcipher *tfm)
static struct akcipher_alg rsa = {
.encrypt = rsa_enc,
.decrypt = rsa_dec,
- .sign = rsa_sign,
- .verify = rsa_verify,
.set_priv_key = rsa_set_priv_key,
.set_pub_key = rsa_set_pub_key,
.max_size = rsa_max_size,
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 4ac3d22256c3..a5a07caf4c76 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -2252,7 +2252,7 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
struct crypto_wait wait;
unsigned int out_len_max, out_len = 0;
int err = -ENOMEM;
- struct scatterlist src, dst, src_tab[2];
+ struct scatterlist src, dst, src_tab[3];
const char *m, *c;
unsigned int m_size, c_size;
const char *op;
@@ -2275,13 +2275,12 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
if (err)
goto free_req;
- err = -ENOMEM;
- out_len_max = crypto_akcipher_maxsize(tfm);
-
/*
* First run test which do not require a private key, such as
* encrypt or verify.
*/
+ err = -ENOMEM;
+ out_len_max = crypto_akcipher_maxsize(tfm);
outbuf_enc = kzalloc(out_len_max, GFP_KERNEL);
if (!outbuf_enc)
goto free_req;
@@ -2307,12 +2306,17 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
goto free_all;
memcpy(xbuf[0], m, m_size);
- sg_init_table(src_tab, 2);
+ sg_init_table(src_tab, 3);
sg_set_buf(&src_tab[0], xbuf[0], 8);
sg_set_buf(&src_tab[1], xbuf[0] + 8, m_size - 8);
- sg_init_one(&dst, outbuf_enc, out_len_max);
- akcipher_request_set_crypt(req, src_tab, &dst, m_size,
- out_len_max);
+ if (vecs->siggen_sigver_test) {
+ sg_set_buf(&src_tab[2], c, c_size);
+ akcipher_request_set_crypt(req, src_tab, NULL, m_size, c_size);
+ } else {
+ sg_init_one(&dst, outbuf_enc, out_len_max);
+ akcipher_request_set_crypt(req, src_tab, &dst, m_size,
+ out_len_max);
+ }
akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
crypto_req_done, &wait);
@@ -2325,18 +2329,21 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
pr_err("alg: akcipher: %s test failed. err %d\n", op, err);
goto free_all;
}
- if (req->dst_len != c_size) {
- pr_err("alg: akcipher: %s test failed. Invalid output len\n",
- op);
- err = -EINVAL;
- goto free_all;
- }
- /* verify that encrypted message is equal to expected */
- if (memcmp(c, outbuf_enc, c_size)) {
- pr_err("alg: akcipher: %s test failed. Invalid output\n", op);
- hexdump(outbuf_enc, c_size);
- err = -EINVAL;
- goto free_all;
+ if (!vecs->siggen_sigver_test) {
+ if (req->dst_len != c_size) {
+ pr_err("alg: akcipher: %s test failed. Invalid output len\n",
+ op);
+ err = -EINVAL;
+ goto free_all;
+ }
+ /* verify that encrypted message is equal to expected */
+ if (memcmp(c, outbuf_enc, c_size)) {
+ pr_err("alg: akcipher: %s test failed. Invalid output\n",
+ op);
+ hexdump(outbuf_enc, c_size);
+ err = -EINVAL;
+ goto free_all;
+ }
}
/*
diff --git a/drivers/crypto/caam/caampkc.c b/drivers/crypto/caam/caampkc.c
index 77ab28a2811a..d7e1fc5bacc5 100644
--- a/drivers/crypto/caam/caampkc.c
+++ b/drivers/crypto/caam/caampkc.c
@@ -994,8 +994,6 @@ static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
static struct akcipher_alg caam_rsa = {
.encrypt = caam_rsa_enc,
.decrypt = caam_rsa_dec,
- .sign = caam_rsa_dec,
- .verify = caam_rsa_enc,
.set_pub_key = caam_rsa_set_pub_key,
.set_priv_key = caam_rsa_set_priv_key,
.max_size = caam_rsa_max_size,
diff --git a/drivers/crypto/ccp/ccp-crypto-rsa.c b/drivers/crypto/ccp/ccp-crypto-rsa.c
index 05850dfd7940..71e40680c880 100644
--- a/drivers/crypto/ccp/ccp-crypto-rsa.c
+++ b/drivers/crypto/ccp/ccp-crypto-rsa.c
@@ -214,8 +214,6 @@ static void ccp_rsa_exit_tfm(struct crypto_akcipher *tfm)
static struct akcipher_alg ccp_rsa_defaults = {
.encrypt = ccp_rsa_encrypt,
.decrypt = ccp_rsa_decrypt,
- .sign = ccp_rsa_decrypt,
- .verify = ccp_rsa_encrypt,
.set_pub_key = ccp_rsa_setpubkey,
.set_priv_key = ccp_rsa_setprivkey,
.max_size = ccp_rsa_maxsize,
diff --git a/drivers/crypto/qat/qat_common/qat_asym_algs.c b/drivers/crypto/qat/qat_common/qat_asym_algs.c
index 320e7854b4ee..c05d03565e96 100644
--- a/drivers/crypto/qat/qat_common/qat_asym_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_asym_algs.c
@@ -1300,8 +1300,6 @@ static void qat_rsa_exit_tfm(struct crypto_akcipher *tfm)
static struct akcipher_alg rsa = {
.encrypt = qat_rsa_enc,
.decrypt = qat_rsa_dec,
- .sign = qat_rsa_dec,
- .verify = qat_rsa_enc,
.set_pub_key = qat_rsa_setpubkey,
.set_priv_key = qat_rsa_setprivkey,
.max_size = qat_rsa_max_size,
diff --git a/include/crypto/akcipher.h b/include/crypto/akcipher.h
index 2d690494568c..d44a3d566413 100644
--- a/include/crypto/akcipher.h
+++ b/include/crypto/akcipher.h
@@ -19,14 +19,20 @@
*
* @base: Common attributes for async crypto requests
* @src: Source data
- * @dst: Destination data
+ * For verify op this is signature + digest, in that case
+ * total size of @src is @src_len + @dst_len.
+ * @dst: Destination data (Should be NULL for verify op)
* @src_len: Size of the input buffer
- * @dst_len: Size of the output buffer. It needs to be at least
- * as big as the expected result depending on the operation
+ * For verify op it's size of signature part of @src, this part
+ * is supposed to be operated by cipher.
+ * @dst_len: Size of @dst buffer (for all ops except verify).
+ * It needs to be at least as big as the expected result
+ * depending on the operation.
* After operation it will be updated with the actual size of the
* result.
* In case of error where the dst sgl size was insufficient,
* it will be updated to the size required for the operation.
+ * For verify op this is size of digest part in @src.
* @__ctx: Start of private context data
*/
struct akcipher_request {
@@ -55,10 +61,9 @@ struct crypto_akcipher {
* algorithm. In case of error, where the dst_len was insufficient,
* the req->dst_len will be updated to the size required for the
* operation
- * @verify: Function performs a sign operation as defined by public key
- * algorithm. In case of error, where the dst_len was insufficient,
- * the req->dst_len will be updated to the size required for the
- * operation
+ * @verify: Function performs a complete verify operation as defined by public
+ * key algorithm, returning verification status. Requires digest
+ * value as input parameter.
* @encrypt: Function performs an encrypt operation as defined by public key
* algorithm. In case of error, where the dst_len was insufficient,
* the req->dst_len will be updated to the size required for the
@@ -238,9 +243,10 @@ static inline void akcipher_request_set_callback(struct akcipher_request *req,
*
* @req: public key request
* @src: ptr to input scatter list
- * @dst: ptr to output scatter list
+ * @dst: ptr to output scatter list or NULL for verify op
* @src_len: size of the src input scatter list to be processed
- * @dst_len: size of the dst output scatter list
+ * @dst_len: size of the dst output scatter list or size of signature
+ * portion in @src for verify op
*/
static inline void akcipher_request_set_crypt(struct akcipher_request *req,
struct scatterlist *src,
@@ -268,7 +274,10 @@ static inline unsigned int crypto_akcipher_maxsize(struct crypto_akcipher *tfm)
{
struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
- return alg->max_size(tfm);
+ if (alg->max_size)
+ return alg->max_size(tfm);
+ else
+ return 0;
}
/**
@@ -334,23 +343,28 @@ static inline int crypto_akcipher_sign(struct akcipher_request *req)
struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
struct crypto_alg *calg = tfm->base.__crt_alg;
- int ret;
+ int ret = -ENOSYS;
crypto_stats_get(calg);
- ret = alg->sign(req);
+ if (alg->sign)
+ ret = alg->sign(req);
crypto_stats_akcipher_sign(ret, calg);
return ret;
}
/**
- * crypto_akcipher_verify() - Invoke public key verify operation
+ * crypto_akcipher_verify() - Invoke public key signature verification
*
- * Function invokes the specific public key verify operation for a given
- * public key algorithm
+ * Function invokes the specific public key signature verification operation
+ * for a given public key algorithm.
*
* @req: asymmetric key request
*
- * Return: zero on success; error code in case of error
+ * Note: req->dst should be NULL, req->src should point to SG of size
+ * (req->src_size + req->dst_size), containing signature (of req->src_size
+ * length) with appended digest (of req->dst_size length).
+ *
+ * Return: zero on verification success; error code in case of error.
*/
static inline int crypto_akcipher_verify(struct akcipher_request *req)
{
@@ -360,7 +374,12 @@ static inline int crypto_akcipher_verify(struct akcipher_request *req)
int ret;
crypto_stats_get(calg);
- ret = alg->verify(req);
+ if (req->dst || !req->dst_len)
+ ret = -EINVAL;
+ else if (alg->verify)
+ ret = alg->verify(req);
+ else
+ ret = -ENOSYS;
crypto_stats_akcipher_verify(ret, calg);
return ret;
}
--
2.11.0
