--- /dev/null
+/*
+ * 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"
+
+#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);
+}
+
+/* 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);
+
+ 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);
+
+ 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");