2016-06-15 15:07:55

by Tudor-Dan Ambarus

[permalink] [raw]
Subject: [PATCH v8 0/3] crypto: caam - add support for RSA algorithm

Changes in v8:
- store raw keys on stack
- use d_sz instead of n_sz for RSA private exponent
- add caam_read_raw_data function for reading RSA modulus raw byte stream
as a positive integer. The function updates the n_sz byte length too.
Needed because the decryption descriptor uses the RSA modulus length as
decryption output length. The accelerator will try to write n_sz bytes
to output SGT, resulting a SGT overfflow if RSA modulus contains leading
zeros.
- add caam_rsa_check_key_length function. Maximum supported modulus size is
4096 bits. Fallback mechanism to be added after removing
the (same) key length constraint from software implementation.

Changes in v7:
- sync with ASN.1 parser

Changes in v6:
- write descriptor PDB fields with inline append
- move Protocol Data Block (pdb) structures to pdb.h
- move setting of PDB fields in new functions
- unmap sec4_sg_dma on done callback
- remove redundant clean code on error path
- fix doc typos

Changes in v5:
- sync with ASN.1 parser

Changes in v4:
- sync with ASN.1 parser

Changes in v3:
- sync with ASN.1 parser

Changes in v2:
- fix memory leaks on error path
- rename struct akcipher_alg rsa to caam_rsa

Tudor Ambarus (3):
crypto: scatterwak - Add scatterwalk_sg_copychunks
crypto: scatterwalk - export scatterwalk_pagedone
crypto: caam - add support for RSA algorithm

crypto/scatterwalk.c | 31 +-
drivers/crypto/caam/Kconfig | 12 +
drivers/crypto/caam/Makefile | 4 +
drivers/crypto/caam/caampkc.c | 693 ++++++++++++++++++++++++++++++++++++++
drivers/crypto/caam/caampkc.h | 70 ++++
drivers/crypto/caam/compat.h | 3 +
drivers/crypto/caam/desc.h | 2 +
drivers/crypto/caam/desc_constr.h | 7 +
drivers/crypto/caam/pdb.h | 51 ++-
drivers/crypto/caam/pkc_desc.c | 36 ++
include/crypto/scatterwalk.h | 4 +
11 files changed, 910 insertions(+), 3 deletions(-)
create mode 100644 drivers/crypto/caam/caampkc.c
create mode 100644 drivers/crypto/caam/caampkc.h
create mode 100644 drivers/crypto/caam/pkc_desc.c

--
1.8.3.1


2016-06-15 14:52:54

by Tudor-Dan Ambarus

[permalink] [raw]
Subject: [PATCH v8 1/3] crypto: scatterwak - Add scatterwalk_sg_copychunks

This patch adds the function scatterwalk_sg_copychunks which writes
a chunk of data from a scatterwalk to another scatterwalk.
It will be used by caam driver to remove the leading zeros
for the output data of the RSA algorithm, after the computation completes.

Signed-off-by: Tudor Ambarus <[email protected]>
---
crypto/scatterwalk.c | 26 ++++++++++++++++++++++++++
include/crypto/scatterwalk.h | 2 ++
2 files changed, 28 insertions(+)

diff --git a/crypto/scatterwalk.c b/crypto/scatterwalk.c
index ea5815c..bc3222d 100644
--- a/crypto/scatterwalk.c
+++ b/crypto/scatterwalk.c
@@ -125,6 +125,32 @@ void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
}
EXPORT_SYMBOL_GPL(scatterwalk_map_and_copy);

+void scatterwalk_sg_copychunks(struct scatter_walk *dest,
+ struct scatter_walk *src, size_t nbytes)
+{
+ for (;;) {
+ unsigned int len_this_page = scatterwalk_pagelen(dest);
+ u8 *vaddr;
+
+ if (len_this_page > nbytes)
+ len_this_page = nbytes;
+
+ vaddr = scatterwalk_map(dest);
+ scatterwalk_copychunks(vaddr, src, len_this_page, 0);
+ scatterwalk_unmap(vaddr);
+
+ scatterwalk_advance(dest, len_this_page);
+
+ if (nbytes == len_this_page)
+ break;
+
+ nbytes -= len_this_page;
+
+ scatterwalk_pagedone(dest, 0, 1);
+ }
+}
+EXPORT_SYMBOL_GPL(scatterwalk_sg_copychunks);
+
int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes)
{
int offset = 0, n = 0;
diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h
index 35f99b6..8b799c5 100644
--- a/include/crypto/scatterwalk.h
+++ b/include/crypto/scatterwalk.h
@@ -86,6 +86,8 @@ static inline void scatterwalk_unmap(void *vaddr)
void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg);
void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
size_t nbytes, int out);
+void scatterwalk_sg_copychunks(struct scatter_walk *dest,
+ struct scatter_walk *src, size_t nbytes);
void *scatterwalk_map(struct scatter_walk *walk);
void scatterwalk_done(struct scatter_walk *walk, int out, int more);

--
1.8.3.1

2016-06-15 14:52:55

by Tudor-Dan Ambarus

[permalink] [raw]
Subject: [PATCH v8 2/3] crypto: scatterwalk - export scatterwalk_pagedone

Used in caam driver. Export the symbol since the caam driver
can be built as a module.

Signed-off-by: Tudor Ambarus <[email protected]>
---
crypto/scatterwalk.c | 5 +++--
include/crypto/scatterwalk.h | 2 ++
2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/crypto/scatterwalk.c b/crypto/scatterwalk.c
index bc3222d..03d34f9 100644
--- a/crypto/scatterwalk.c
+++ b/crypto/scatterwalk.c
@@ -47,8 +47,8 @@ void *scatterwalk_map(struct scatter_walk *walk)
}
EXPORT_SYMBOL_GPL(scatterwalk_map);

-static void scatterwalk_pagedone(struct scatter_walk *walk, int out,
- unsigned int more)
+void scatterwalk_pagedone(struct scatter_walk *walk, int out,
+ unsigned int more)
{
if (out) {
struct page *page;
@@ -69,6 +69,7 @@ static void scatterwalk_pagedone(struct scatter_walk *walk, int out,
scatterwalk_start(walk, sg_next(walk->sg));
}
}
+EXPORT_SYMBOL_GPL(scatterwalk_pagedone);

void scatterwalk_done(struct scatter_walk *walk, int out, int more)
{
diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h
index 8b799c5..6535a20 100644
--- a/include/crypto/scatterwalk.h
+++ b/include/crypto/scatterwalk.h
@@ -89,6 +89,8 @@ void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
void scatterwalk_sg_copychunks(struct scatter_walk *dest,
struct scatter_walk *src, size_t nbytes);
void *scatterwalk_map(struct scatter_walk *walk);
+void scatterwalk_pagedone(struct scatter_walk *walk, int out,
+ unsigned int more);
void scatterwalk_done(struct scatter_walk *walk, int out, int more);

void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
--
1.8.3.1

2016-06-15 14:52:58

by Tudor-Dan Ambarus

[permalink] [raw]
Subject: [PATCH v8 3/3] crypto: caam - add support for RSA algorithm

Add RSA support to caam driver.

Initial author is Yashpal Dutta <[email protected]>.

Signed-off-by: Tudor Ambarus <[email protected]>
---
drivers/crypto/caam/Kconfig | 12 +
drivers/crypto/caam/Makefile | 4 +
drivers/crypto/caam/caampkc.c | 693 ++++++++++++++++++++++++++++++++++++++
drivers/crypto/caam/caampkc.h | 70 ++++
drivers/crypto/caam/compat.h | 3 +
drivers/crypto/caam/desc.h | 2 +
drivers/crypto/caam/desc_constr.h | 7 +
drivers/crypto/caam/pdb.h | 51 ++-
drivers/crypto/caam/pkc_desc.c | 36 ++
9 files changed, 877 insertions(+), 1 deletion(-)
create mode 100644 drivers/crypto/caam/caampkc.c
create mode 100644 drivers/crypto/caam/caampkc.h
create mode 100644 drivers/crypto/caam/pkc_desc.c

diff --git a/drivers/crypto/caam/Kconfig b/drivers/crypto/caam/Kconfig
index ff54c42..64bf302 100644
--- a/drivers/crypto/caam/Kconfig
+++ b/drivers/crypto/caam/Kconfig
@@ -99,6 +99,18 @@ config CRYPTO_DEV_FSL_CAAM_AHASH_API
To compile this as a module, choose M here: the module
will be called caamhash.

+config CRYPTO_DEV_FSL_CAAM_PKC_API
+ tristate "Register public key cryptography implementations with Crypto API"
+ depends on CRYPTO_DEV_FSL_CAAM && CRYPTO_DEV_FSL_CAAM_JR
+ default y
+ select CRYPTO_RSA
+ help
+ Selecting this will allow SEC Public key support for RSA.
+ Supported cryptographic primitives: encryption, decryption,
+ signature and verification.
+ To compile this as a module, choose M here: the module
+ will be called caam_pkc.
+
config CRYPTO_DEV_FSL_CAAM_RNG_API
tristate "Register caam device for hwrng API"
depends on CRYPTO_DEV_FSL_CAAM && CRYPTO_DEV_FSL_CAAM_JR
diff --git a/drivers/crypto/caam/Makefile b/drivers/crypto/caam/Makefile
index 550758a..399ad55 100644
--- a/drivers/crypto/caam/Makefile
+++ b/drivers/crypto/caam/Makefile
@@ -5,11 +5,15 @@ ifeq ($(CONFIG_CRYPTO_DEV_FSL_CAAM_DEBUG), y)
EXTRA_CFLAGS := -DDEBUG
endif

+ccflags-y += -I$(srctree)/crypto
+
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM) += caam.o
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_JR) += caam_jr.o
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API) += caamalg.o
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API) += caamhash.o
obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API) += caamrng.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PKC_API) += caam_pkc.o

caam-objs := ctrl.o
caam_jr-objs := jr.o key_gen.o error.o
+caam_pkc-y := caampkc.o pkc_desc.o
diff --git a/drivers/crypto/caam/caampkc.c b/drivers/crypto/caam/caampkc.c
new file mode 100644
index 0000000..36d3419
--- /dev/null
+++ b/drivers/crypto/caam/caampkc.c
@@ -0,0 +1,693 @@
+/*
+ * caam - Freescale FSL CAAM support for Public Key Cryptography
+ *
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
+ * all the desired key parameters, input and output pointers.
+ */
+#include "compat.h"
+#include "regs.h"
+#include "intern.h"
+#include "jr.h"
+#include "error.h"
+#include "desc_constr.h"
+#include "sg_sw_sec4.h"
+#include "caampkc.h"
+#include "rsapubkey-asn1.h"
+#include "rsaprivkey-asn1.h"
+
+#define DESC_RSA_PUB_LEN (2 * CAAM_CMD_SZ + sizeof(struct rsa_pub_pdb))
+#define DESC_RSA_PRIV_F1_LEN (2 * CAAM_CMD_SZ + \
+ sizeof(struct rsa_priv_f1_pdb))
+
+static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
+ struct akcipher_request *req)
+{
+ dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
+ dma_unmap_sg(dev, req->src, edesc->src_nents, DMA_TO_DEVICE);
+
+ if (edesc->sec4_sg_bytes)
+ dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
+ DMA_TO_DEVICE);
+}
+
+static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
+ struct akcipher_request *req)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+ struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
+
+ dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
+ dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
+}
+
+static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
+ struct akcipher_request *req)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+ struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
+
+ dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
+ dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
+}
+
+static size_t caam_count_leading_zeros(u8 *ptr, size_t nbytes)
+{
+ size_t nr_zeros = 0;
+
+ while (!(*ptr) && nbytes) {
+ nbytes--;
+ ptr++;
+ nr_zeros++;
+ }
+
+ return nr_zeros;
+}
+
+static size_t scatterwalk_skip_leading_zeros(struct scatter_walk *walk,
+ size_t nbytes)
+{
+ size_t len_this_page, nr_zeros, cnt = 0;
+ u8 *vaddr;
+
+ for (;;) {
+ nr_zeros = 0;
+ len_this_page = scatterwalk_pagelen(walk);
+
+ if (len_this_page > nbytes)
+ len_this_page = nbytes;
+
+ vaddr = scatterwalk_map(walk);
+ nr_zeros = caam_count_leading_zeros(vaddr, len_this_page);
+ scatterwalk_unmap(vaddr);
+
+ /* count total number of zeros */
+ cnt += nr_zeros;
+
+ /* advance scatterwalk to the nonzero data */
+ scatterwalk_advance(walk, nr_zeros);
+
+ if (nr_zeros < len_this_page || nbytes == len_this_page)
+ break;
+
+ nbytes -= len_this_page;
+
+ scatterwalk_pagedone(walk, 0, 1);
+ }
+
+ return cnt;
+}
+
+/*
+ * This function drops the leading zeros and copies the data to the initial
+ * pointer so that it can be freed later on. Returns the updated data length.
+ */
+static size_t drop_leading_zeros(struct scatterlist *sg, size_t nbytes)
+{
+ struct scatter_walk walk_src, walk_dst;
+ size_t nr_zeros = 0;
+
+ scatterwalk_start(&walk_src, sg);
+ nr_zeros = scatterwalk_skip_leading_zeros(&walk_src, nbytes);
+
+ if (nr_zeros) {
+ nbytes = nbytes - nr_zeros;
+
+ scatterwalk_start(&walk_dst, sg);
+ scatterwalk_sg_copychunks(&walk_dst, &walk_src, nbytes);
+ scatterwalk_done(&walk_dst, 0, 0);
+ }
+
+ scatterwalk_done(&walk_src, 0, 0);
+
+ return nbytes;
+}
+
+/* RSA Job Completion handler */
+static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
+{
+ struct akcipher_request *req = context;
+ struct rsa_edesc *edesc;
+
+ if (err)
+ caam_jr_strstatus(dev, err);
+
+ /*
+ * RSA's output is expected to be a big integer. Drop the leading
+ * zeros since they are not meaningful in the world of numbers.
+ */
+ req->dst_len = drop_leading_zeros(req->dst, req->dst_len);
+
+ edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
+
+ rsa_pub_unmap(dev, edesc, req);
+ rsa_io_unmap(dev, edesc, req);
+ kfree(edesc);
+
+ akcipher_request_complete(req, err);
+}
+
+static void rsa_priv_f1_done(struct device *dev, u32 *desc, u32 err,
+ void *context)
+{
+ struct akcipher_request *req = context;
+ struct rsa_edesc *edesc;
+
+ if (err)
+ caam_jr_strstatus(dev, err);
+
+ /*
+ * RSA's output is expected to be a big integer. Drop the leading
+ * zeros since they are not meaningful in the world of numbers.
+ */
+ req->dst_len = drop_leading_zeros(req->dst, req->dst_len);
+
+ edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
+
+ rsa_priv_f1_unmap(dev, edesc, req);
+ rsa_io_unmap(dev, edesc, req);
+ kfree(edesc);
+
+ akcipher_request_complete(req, err);
+}
+
+static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req,
+ size_t desclen)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct device *dev = ctx->dev;
+ struct rsa_edesc *edesc;
+ gfp_t flags = (req->base.flags & (CRYPTO_TFM_REQ_MAY_BACKLOG |
+ CRYPTO_TFM_REQ_MAY_SLEEP)) ? GFP_KERNEL : GFP_ATOMIC;
+ int sgc;
+ int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
+ int src_nents, dst_nents;
+
+ src_nents = sg_nents_for_len(req->src, req->src_len);
+ dst_nents = sg_nents_for_len(req->dst, req->dst_len);
+
+ if (src_nents > 1)
+ sec4_sg_len = src_nents;
+ if (dst_nents > 1)
+ sec4_sg_len += dst_nents;
+
+ sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry);
+
+ /* allocate space for base edesc, hw desc commands and link tables */
+ edesc = kzalloc(sizeof(*edesc) + desclen + sec4_sg_bytes,
+ GFP_DMA | flags);
+ if (!edesc)
+ return ERR_PTR(-ENOMEM);
+
+ sgc = dma_map_sg(dev, req->src, src_nents, DMA_TO_DEVICE);
+ if (unlikely(!sgc)) {
+ dev_err(dev, "unable to map source\n");
+ goto src_fail;
+ }
+
+ sgc = dma_map_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
+ if (unlikely(!sgc)) {
+ dev_err(dev, "unable to map destination\n");
+ goto dst_fail;
+ }
+
+ edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen;
+
+ sec4_sg_index = 0;
+ if (src_nents > 1) {
+ sg_to_sec4_sg_last(req->src, src_nents, edesc->sec4_sg, 0);
+ sec4_sg_index += src_nents;
+ }
+ if (dst_nents > 1)
+ sg_to_sec4_sg_last(req->dst, dst_nents,
+ edesc->sec4_sg + sec4_sg_index, 0);
+
+ /* Save nents for later use in Job Descriptor */
+ edesc->src_nents = src_nents;
+ edesc->dst_nents = dst_nents;
+
+ if (!sec4_sg_bytes)
+ return edesc;
+
+ edesc->sec4_sg_dma = dma_map_single(dev, edesc->sec4_sg,
+ sec4_sg_bytes, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, edesc->sec4_sg_dma)) {
+ dev_err(dev, "unable to map S/G table\n");
+ goto sec4_sg_fail;
+ }
+
+ edesc->sec4_sg_bytes = sec4_sg_bytes;
+
+ return edesc;
+
+sec4_sg_fail:
+ dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
+dst_fail:
+ dma_unmap_sg(dev, req->src, src_nents, DMA_TO_DEVICE);
+src_fail:
+ kfree(edesc);
+ return ERR_PTR(-ENOMEM);
+}
+
+static int set_rsa_pub_pdb(struct akcipher_request *req,
+ struct rsa_edesc *edesc)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+ struct device *dev = ctx->dev;
+ struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
+ int sec4_sg_index = 0;
+
+ pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, pdb->n_dma)) {
+ dev_err(dev, "Unable to map RSA modulus memory\n");
+ return -ENOMEM;
+ }
+
+ pdb->e_dma = dma_map_single(dev, key->e, key->e_sz, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, pdb->e_dma)) {
+ dev_err(dev, "Unable to map RSA public exponent memory\n");
+ dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
+ return -ENOMEM;
+ }
+
+ if (edesc->src_nents > 1) {
+ pdb->sgf |= RSA_PDB_SGF_F;
+ pdb->f_dma = edesc->sec4_sg_dma;
+ sec4_sg_index += edesc->src_nents;
+ } else {
+ pdb->f_dma = sg_dma_address(req->src);
+ }
+
+ if (edesc->dst_nents > 1) {
+ pdb->sgf |= RSA_PDB_SGF_G;
+ pdb->g_dma = edesc->sec4_sg_dma +
+ sec4_sg_index * sizeof(struct sec4_sg_entry);
+ } else {
+ pdb->g_dma = sg_dma_address(req->dst);
+ }
+
+ pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz;
+ pdb->f_len = req->src_len;
+
+ return 0;
+}
+
+static int set_rsa_priv_f1_pdb(struct akcipher_request *req,
+ struct rsa_edesc *edesc)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+ struct device *dev = ctx->dev;
+ struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
+ int sec4_sg_index = 0;
+
+ pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, pdb->n_dma)) {
+ dev_err(dev, "Unable to map modulus memory\n");
+ return -ENOMEM;
+ }
+
+ pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, pdb->d_dma)) {
+ dev_err(dev, "Unable to map RSA private exponent memory\n");
+ dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
+ return -ENOMEM;
+ }
+
+ if (edesc->src_nents > 1) {
+ pdb->sgf |= RSA_PRIV_PDB_SGF_G;
+ pdb->g_dma = edesc->sec4_sg_dma;
+ sec4_sg_index += edesc->src_nents;
+ } else {
+ pdb->g_dma = sg_dma_address(req->src);
+ }
+
+ if (edesc->dst_nents > 1) {
+ pdb->sgf |= RSA_PRIV_PDB_SGF_F;
+ pdb->f_dma = edesc->sec4_sg_dma +
+ sec4_sg_index * sizeof(struct sec4_sg_entry);
+ } else {
+ pdb->f_dma = sg_dma_address(req->dst);
+ }
+
+ pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
+
+ return 0;
+}
+
+static int caam_rsa_enc(struct akcipher_request *req)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+ struct device *jrdev = ctx->dev;
+ struct rsa_edesc *edesc;
+ int ret;
+
+ if (unlikely(!key->n || !key->e))
+ return -EINVAL;
+
+ if (req->dst_len < key->n_sz) {
+ req->dst_len = key->n_sz;
+ dev_err(jrdev, "Output buffer length less than parameter n\n");
+ return -EOVERFLOW;
+ }
+
+ /* Allocate extended descriptor */
+ edesc = rsa_edesc_alloc(req, DESC_RSA_PUB_LEN);
+ if (IS_ERR(edesc))
+ return PTR_ERR(edesc);
+
+ /* Set RSA Encrypt Protocol Data Block */
+ ret = set_rsa_pub_pdb(req, edesc);
+ if (ret)
+ goto init_fail;
+
+ /* Initialize Job Descriptor */
+ init_rsa_pub_desc(edesc->hw_desc, &edesc->pdb.pub);
+
+ ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_pub_done, req);
+ if (!ret)
+ return -EINPROGRESS;
+
+ rsa_pub_unmap(jrdev, edesc, req);
+
+init_fail:
+ rsa_io_unmap(jrdev, edesc, req);
+ kfree(edesc);
+ return ret;
+}
+
+static int caam_rsa_dec(struct akcipher_request *req)
+{
+ struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+ struct device *jrdev = ctx->dev;
+ struct rsa_edesc *edesc;
+ int ret;
+
+ if (unlikely(!key->n || !key->d))
+ return -EINVAL;
+
+ if (req->dst_len < key->n_sz) {
+ req->dst_len = key->n_sz;
+ dev_err(jrdev, "Output buffer length less than parameter n\n");
+ return -EOVERFLOW;
+ }
+
+ /* Allocate extended descriptor */
+ edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F1_LEN);
+ if (IS_ERR(edesc))
+ return PTR_ERR(edesc);
+
+ /* Set RSA Decrypt Protocol Data Block - Private Key Form #1 */
+ ret = set_rsa_priv_f1_pdb(req, edesc);
+ if (ret)
+ goto init_fail;
+
+ /* Initialize Job Descriptor */
+ init_rsa_priv_f1_desc(edesc->hw_desc, &edesc->pdb.priv_f1);
+
+ ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f1_done, req);
+ if (!ret)
+ return -EINPROGRESS;
+
+ rsa_priv_f1_unmap(jrdev, edesc, req);
+
+init_fail:
+ rsa_io_unmap(jrdev, edesc, req);
+ kfree(edesc);
+ return ret;
+}
+
+static void caam_rsa_free_key(struct caam_rsa_key *key)
+{
+ kzfree(key->d);
+ kfree(key->e);
+ kfree(key->n);
+ key->d = NULL;
+ key->e = NULL;
+ key->n = NULL;
+ key->d_sz = 0;
+ key->e_sz = 0;
+ key->n_sz = 0;
+}
+
+/**
+ * caam_read_raw_data - Read a raw byte stream as a positive integer.
+ * The function skips buffer's leading zeros, copies the remained data
+ * to a buffer allocated in the GFP_DMA | GFP_KERNEL zone and returns
+ * the address of the new buffer.
+ *
+ * @buf : The data to read
+ * @nbytes: The amount of data to read
+ */
+static inline u8 *caam_read_raw_data(const u8 *buf, size_t *nbytes)
+{
+ u8 *val;
+
+ while (!*buf && *nbytes) {
+ buf++;
+ (*nbytes)--;
+ }
+
+ val = kzalloc(*nbytes, GFP_DMA | GFP_KERNEL);
+ if (!val)
+ return NULL;
+
+ memcpy(val, buf, *nbytes);
+
+ return val;
+}
+
+static int caam_rsa_check_key_length(unsigned int len)
+{
+ if (len > 4096)
+ return -EINVAL;
+ return 0;
+}
+
+static int caam_rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
+ unsigned int keylen)
+{
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct rsa_key raw_key = {0};
+ struct caam_rsa_key *rsa_key = &ctx->key;
+ int ret;
+
+ /* Free the old RSA key if any */
+ caam_rsa_free_key(rsa_key);
+
+ ret = rsa_parse_pub_key(&raw_key, key, keylen);
+ if (ret)
+ return ret;
+
+ /* Copy key in DMA zone */
+ rsa_key->e = kzalloc(raw_key.e_sz, GFP_DMA | GFP_KERNEL);
+ if (!rsa_key->e)
+ goto err;
+
+ /*
+ * Skip leading zeros and copy the positive integer to a buffer
+ * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
+ * expects a positive integer for the RSA modulus and uses its length as
+ * decryption output length.
+ */
+ rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
+ if (!rsa_key->n)
+ goto err;
+
+ if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
+ caam_rsa_free_key(rsa_key);
+ return -EINVAL;
+ }
+
+ rsa_key->e_sz = raw_key.e_sz;
+ rsa_key->n_sz = raw_key.n_sz;
+
+ memcpy(rsa_key->e, raw_key.e, raw_key.e_sz);
+
+ return 0;
+err:
+ caam_rsa_free_key(rsa_key);
+ return -ENOMEM;
+}
+
+static int caam_rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
+ unsigned int keylen)
+{
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct rsa_key raw_key = {0};
+ struct caam_rsa_key *rsa_key = &ctx->key;
+ int ret;
+
+ /* Free the old RSA key if any */
+ caam_rsa_free_key(rsa_key);
+
+ ret = rsa_parse_priv_key(&raw_key, key, keylen);
+ if (ret)
+ return ret;
+
+ /* Copy key in DMA zone */
+ rsa_key->d = kzalloc(raw_key.d_sz, GFP_DMA | GFP_KERNEL);
+ if (!rsa_key->d)
+ goto err;
+
+ rsa_key->e = kzalloc(raw_key.e_sz, GFP_DMA | GFP_KERNEL);
+ if (!rsa_key->e)
+ goto err;
+
+ /*
+ * Skip leading zeros and copy the positive integer to a buffer
+ * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
+ * expects a positive integer for the RSA modulus and uses its length as
+ * decryption output length.
+ */
+ rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
+ if (!rsa_key->n)
+ goto err;
+
+ if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
+ caam_rsa_free_key(rsa_key);
+ return -EINVAL;
+ }
+
+ rsa_key->d_sz = raw_key.d_sz;
+ rsa_key->e_sz = raw_key.e_sz;
+ rsa_key->n_sz = raw_key.n_sz;
+
+ memcpy(rsa_key->d, raw_key.d, raw_key.d_sz);
+ memcpy(rsa_key->e, raw_key.e, raw_key.e_sz);
+
+ return 0;
+
+err:
+ caam_rsa_free_key(rsa_key);
+ return -ENOMEM;
+}
+
+static int caam_rsa_max_size(struct crypto_akcipher *tfm)
+{
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+
+ return (key->n) ? key->n_sz : -EINVAL;
+}
+
+/* Per session pkc's driver context creation function */
+static int caam_rsa_init_tfm(struct crypto_akcipher *tfm)
+{
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+
+ ctx->dev = caam_jr_alloc();
+
+ if (IS_ERR(ctx->dev)) {
+ dev_err(ctx->dev, "Job Ring Device allocation for transform failed\n");
+ return PTR_ERR(ctx->dev);
+ }
+
+ return 0;
+}
+
+/* Per session pkc's driver context cleanup function */
+static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
+{
+ struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct caam_rsa_key *key = &ctx->key;
+
+ caam_rsa_free_key(key);
+ caam_jr_free(ctx->dev);
+}
+
+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,
+ .init = caam_rsa_init_tfm,
+ .exit = caam_rsa_exit_tfm,
+ .base = {
+ .cra_name = "rsa",
+ .cra_driver_name = "rsa-caam",
+ .cra_priority = 3000,
+ .cra_module = THIS_MODULE,
+ .cra_ctxsize = sizeof(struct caam_rsa_ctx),
+ },
+};
+
+/* Public Key Cryptography module initialization handler */
+static int __init caam_pkc_init(void)
+{
+ struct device_node *dev_node;
+ struct platform_device *pdev;
+ struct device *ctrldev;
+ struct caam_drv_private *priv;
+ u32 cha_inst, pk_inst;
+ int err;
+
+ dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0");
+ if (!dev_node) {
+ dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec4.0");
+ if (!dev_node)
+ return -ENODEV;
+ }
+
+ pdev = of_find_device_by_node(dev_node);
+ if (!pdev) {
+ of_node_put(dev_node);
+ return -ENODEV;
+ }
+
+ ctrldev = &pdev->dev;
+ priv = dev_get_drvdata(ctrldev);
+ of_node_put(dev_node);
+
+ /*
+ * If priv is NULL, it's probably because the caam driver wasn't
+ * properly initialized (e.g. RNG4 init failed). Thus, bail out here.
+ */
+ if (!priv)
+ return -ENODEV;
+
+ /* Determine public key hardware accelerator presence. */
+ cha_inst = rd_reg32(&priv->ctrl->perfmon.cha_num_ls);
+ pk_inst = (cha_inst & CHA_ID_LS_PK_MASK) >> CHA_ID_LS_PK_SHIFT;
+
+ /* Do not register algorithms if PKHA is not present. */
+ if (!pk_inst)
+ return -ENODEV;
+
+ err = crypto_register_akcipher(&caam_rsa);
+ if (err)
+ dev_warn(ctrldev, "%s alg registration failed\n",
+ caam_rsa.base.cra_driver_name);
+ else
+ dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n");
+
+ return err;
+}
+
+static void __exit caam_pkc_exit(void)
+{
+ crypto_unregister_akcipher(&caam_rsa);
+}
+
+module_init(caam_pkc_init);
+module_exit(caam_pkc_exit);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("FSL CAAM support for PKC functions of crypto API");
+MODULE_AUTHOR("Freescale Semiconductor");
diff --git a/drivers/crypto/caam/caampkc.h b/drivers/crypto/caam/caampkc.h
new file mode 100644
index 0000000..f595d15
--- /dev/null
+++ b/drivers/crypto/caam/caampkc.h
@@ -0,0 +1,70 @@
+/*
+ * caam - Freescale FSL CAAM support for Public Key Cryptography descriptors
+ *
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
+ * all the desired key parameters, input and output pointers.
+ */
+
+#ifndef _PKC_DESC_H_
+#define _PKC_DESC_H_
+#include "compat.h"
+#include "pdb.h"
+
+/**
+ * caam_rsa_key - CAAM RSA key structure. Keys are allocated in DMA zone.
+ * @n : RSA modulus raw byte stream
+ * @e : RSA public exponent raw byte stream
+ * @d : RSA private exponent raw byte stream
+ * @n_sz : length in bytes of RSA modulus n
+ * @e_sz : length in bytes of RSA public exponent
+ * @d_sz : length in bytes of RSA private exponent
+ */
+struct caam_rsa_key {
+ u8 *n;
+ u8 *e;
+ u8 *d;
+ size_t n_sz;
+ size_t e_sz;
+ size_t d_sz;
+};
+
+/**
+ * caam_rsa_ctx - per session context.
+ * @key : RSA key in DMA zone
+ * @dev : device structure
+ */
+struct caam_rsa_ctx {
+ struct caam_rsa_key key;
+ struct device *dev;
+};
+
+/**
+ * rsa_edesc - s/w-extended rsa descriptor
+ * @src_nents : number of segments in input scatterlist
+ * @dst_nents : number of segments in output scatterlist
+ * @sec4_sg_bytes : length of h/w link table
+ * @sec4_sg_dma : dma address of h/w link table
+ * @sec4_sg : pointer to h/w link table
+ * @pdb : specific RSA Protocol Data Block (PDB)
+ * @hw_desc : descriptor followed by link tables if any
+ */
+struct rsa_edesc {
+ int src_nents;
+ int dst_nents;
+ int sec4_sg_bytes;
+ dma_addr_t sec4_sg_dma;
+ struct sec4_sg_entry *sec4_sg;
+ union {
+ struct rsa_pub_pdb pub;
+ struct rsa_priv_f1_pdb priv_f1;
+ } pdb;
+ u32 hw_desc[];
+};
+
+/* Descriptor construction primitives. */
+void init_rsa_pub_desc(u32 *desc, struct rsa_pub_pdb *pdb);
+void init_rsa_priv_f1_desc(u32 *desc, struct rsa_priv_f1_pdb *pdb);
+
+#endif
diff --git a/drivers/crypto/caam/compat.h b/drivers/crypto/caam/compat.h
index b6955ec..7149cd2 100644
--- a/drivers/crypto/caam/compat.h
+++ b/drivers/crypto/caam/compat.h
@@ -35,8 +35,11 @@
#include <crypto/md5.h>
#include <crypto/internal/aead.h>
#include <crypto/authenc.h>
+#include <crypto/akcipher.h>
#include <crypto/scatterwalk.h>
#include <crypto/internal/skcipher.h>
#include <crypto/internal/hash.h>
+#include <crypto/internal/rsa.h>
+#include <crypto/internal/akcipher.h>

#endif /* !defined(CAAM_COMPAT_H) */
diff --git a/drivers/crypto/caam/desc.h b/drivers/crypto/caam/desc.h
index d8d5584..26427c1 100644
--- a/drivers/crypto/caam/desc.h
+++ b/drivers/crypto/caam/desc.h
@@ -453,6 +453,8 @@ struct sec4_sg_entry {
#define OP_PCLID_PUBLICKEYPAIR (0x14 << OP_PCLID_SHIFT)
#define OP_PCLID_DSASIGN (0x15 << OP_PCLID_SHIFT)
#define OP_PCLID_DSAVERIFY (0x16 << OP_PCLID_SHIFT)
+#define OP_PCLID_RSAENC_PUBKEY (0x18 << OP_PCLID_SHIFT)
+#define OP_PCLID_RSADEC_PRVKEY (0x19 << OP_PCLID_SHIFT)

/* Assuming OP_TYPE = OP_TYPE_DECAP_PROTOCOL/ENCAP_PROTOCOL */
#define OP_PCLID_IPSEC (0x01 << OP_PCLID_SHIFT)
diff --git a/drivers/crypto/caam/desc_constr.h b/drivers/crypto/caam/desc_constr.h
index ae3aef6..d3869b9 100644
--- a/drivers/crypto/caam/desc_constr.h
+++ b/drivers/crypto/caam/desc_constr.h
@@ -77,6 +77,13 @@ static inline void init_job_desc(u32 *desc, u32 options)
init_desc(desc, CMD_DESC_HDR | options);
}

+static inline void init_job_desc_pdb(u32 *desc, u32 options, size_t pdb_bytes)
+{
+ u32 pdb_len = (pdb_bytes + CAAM_CMD_SZ - 1) / CAAM_CMD_SZ;
+
+ init_job_desc(desc, (((pdb_len + 1) << HDR_START_IDX_SHIFT)) | options);
+}
+
static inline void append_ptr(u32 *desc, dma_addr_t ptr)
{
dma_addr_t *offset = (dma_addr_t *)desc_end(desc);
diff --git a/drivers/crypto/caam/pdb.h b/drivers/crypto/caam/pdb.h
index d383573..aaa00dd 100644
--- a/drivers/crypto/caam/pdb.h
+++ b/drivers/crypto/caam/pdb.h
@@ -1,12 +1,13 @@
/*
* CAAM Protocol Data Block (PDB) definition header file
*
- * Copyright 2008-2012 Freescale Semiconductor, Inc.
+ * Copyright 2008-2016 Freescale Semiconductor, Inc.
*
*/

#ifndef CAAM_PDB_H
#define CAAM_PDB_H
+#include "compat.h"

/*
* PDB- IPSec ESP Header Modification Options
@@ -476,4 +477,52 @@ struct dsa_verify_pdb {
u8 *ab; /* only used if ECC processing */
};

+/* RSA Protocol Data Block */
+#define RSA_PDB_SGF_SHIFT 28
+#define RSA_PDB_E_SHIFT 12
+#define RSA_PDB_E_MASK (0xFFF << RSA_PDB_E_SHIFT)
+#define RSA_PDB_D_SHIFT 12
+#define RSA_PDB_D_MASK (0xFFF << RSA_PDB_D_SHIFT)
+
+#define RSA_PDB_SGF_F (0x8 << RSA_PDB_SGF_SHIFT)
+#define RSA_PDB_SGF_G (0x4 << RSA_PDB_SGF_SHIFT)
+#define RSA_PRIV_PDB_SGF_F (0x4 << RSA_PDB_SGF_SHIFT)
+#define RSA_PRIV_PDB_SGF_G (0x8 << RSA_PDB_SGF_SHIFT)
+
+#define RSA_PRIV_KEY_FRM_1 0
+
+/**
+ * RSA Encrypt Protocol Data Block
+ * @sgf: scatter-gather field
+ * @f_dma: dma address of input data
+ * @g_dma: dma address of encrypted output data
+ * @n_dma: dma address of RSA modulus
+ * @e_dma: dma address of RSA public exponent
+ * @f_len: length in octets of the input data
+ */
+struct rsa_pub_pdb {
+ u32 sgf;
+ dma_addr_t f_dma;
+ dma_addr_t g_dma;
+ dma_addr_t n_dma;
+ dma_addr_t e_dma;
+ u32 f_len;
+} __packed;
+
+/**
+ * RSA Decrypt PDB - Private Key Form #1
+ * @sgf: scatter-gather field
+ * @g_dma: dma address of encrypted input data
+ * @f_dma: dma address of output data
+ * @n_dma: dma address of RSA modulus
+ * @d_dma: dma address of RSA private exponent
+ */
+struct rsa_priv_f1_pdb {
+ u32 sgf;
+ dma_addr_t g_dma;
+ dma_addr_t f_dma;
+ dma_addr_t n_dma;
+ dma_addr_t d_dma;
+} __packed;
+
#endif
diff --git a/drivers/crypto/caam/pkc_desc.c b/drivers/crypto/caam/pkc_desc.c
new file mode 100644
index 0000000..4e4183e
--- /dev/null
+++ b/drivers/crypto/caam/pkc_desc.c
@@ -0,0 +1,36 @@
+/*
+ * caam - Freescale FSL CAAM support for Public Key Cryptography descriptors
+ *
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
+ * all the desired key parameters, input and output pointers.
+ */
+#include "caampkc.h"
+#include "desc_constr.h"
+
+/* Descriptor for RSA Public operation */
+void init_rsa_pub_desc(u32 *desc, struct rsa_pub_pdb *pdb)
+{
+ init_job_desc_pdb(desc, 0, sizeof(*pdb));
+ append_cmd(desc, pdb->sgf);
+ append_ptr(desc, pdb->f_dma);
+ append_ptr(desc, pdb->g_dma);
+ append_ptr(desc, pdb->n_dma);
+ append_ptr(desc, pdb->e_dma);
+ append_cmd(desc, pdb->f_len);
+ append_operation(desc, OP_TYPE_UNI_PROTOCOL | OP_PCLID_RSAENC_PUBKEY);
+}
+
+/* Descriptor for RSA Private operation - Private Key Form #1 */
+void init_rsa_priv_f1_desc(u32 *desc, struct rsa_priv_f1_pdb *pdb)
+{
+ init_job_desc_pdb(desc, 0, sizeof(*pdb));
+ append_cmd(desc, pdb->sgf);
+ append_ptr(desc, pdb->g_dma);
+ append_ptr(desc, pdb->f_dma);
+ append_ptr(desc, pdb->n_dma);
+ append_ptr(desc, pdb->d_dma);
+ append_operation(desc, OP_TYPE_UNI_PROTOCOL | OP_PCLID_RSADEC_PRVKEY |
+ RSA_PRIV_KEY_FRM_1);
+}
--
1.8.3.1

2016-06-20 10:56:48

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH v8 1/3] crypto: scatterwak - Add scatterwalk_sg_copychunks

On Wed, Jun 15, 2016 at 05:52:42PM +0300, Tudor Ambarus wrote:
> This patch adds the function scatterwalk_sg_copychunks which writes
> a chunk of data from a scatterwalk to another scatterwalk.
> It will be used by caam driver to remove the leading zeros
> for the output data of the RSA algorithm, after the computation completes.
>
> Signed-off-by: Tudor Ambarus <[email protected]>

Not only does dropping leading zeroes lead to questions about
information leaks, but it makes every one of our RSA drivers
look crap.

So I'm going to change this and make it not skip leading zeroes.

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt