From patchwork Fri Jan 25 18:01:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 10781839 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E8B111399 for ; Fri, 25 Jan 2019 18:13:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D74793040F for ; Fri, 25 Jan 2019 18:13:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D54773041F; Fri, 25 Jan 2019 18:13:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 884BD3040F for ; Fri, 25 Jan 2019 18:13:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729316AbfAYSNK (ORCPT ); Fri, 25 Jan 2019 13:13:10 -0500 Received: from vmicros1.altlinux.org ([194.107.17.57]:45690 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726335AbfAYSNK (ORCPT ); Fri, 25 Jan 2019 13:13:10 -0500 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id EAB9F72CC61; Fri, 25 Jan 2019 21:01:24 +0300 (MSK) Received: from beacon.altlinux.org (unknown [185.6.174.98]) by imap.altlinux.org (Postfix) with ESMTPSA id AB9474A4A16; Fri, 25 Jan 2019 21:01:24 +0300 (MSK) From: Vitaly Chikunov To: Herbert Xu , "David S. Miller" , David Howells , Maxime Coquelin , Alexandre Torgue , =?utf-8?q?Horia_Geant=C4=83?= , Aymen Sghaier , Tom Lendacky , Gary Hook , Giovanni Cabiddu , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, keyrings@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, qat-linux@intel.com Subject: [RFC PATCH v4] akcipher: new verify API for public key algorithms Date: Fri, 25 Jan 2019 21:01:16 +0300 Message-Id: <20190125180116.13702-1-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 --- 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; }