#include <linux/module.h>
#include <linux/sched.h>
#include <linux/scatterlist.h>
#include <linux/string.h>
#include <linux/crypto.h>
#include <crypto/algapi.h>
#include <crypto/internal/rsa.h>
#include <crypto/internal/akcipher.h>
#include <crypto/akcipher.h>
#include <crypto/scatterwalk.h>
#include "ccp-crypto.h"
static inline struct akcipher_request *akcipher_request_cast(
struct crypto_async_request *req)
{
return container_of(req, struct akcipher_request, base);
}
static inline int ccp_copy_and_save_keypart(u8 **kpbuf, unsigned int *kplen,
const u8 *buf, size_t sz)
{
int nskip;
for (nskip = 0; nskip < sz; nskip++)
if (buf[nskip])
break;
*kplen = sz - nskip;
*kpbuf = kmemdup(buf + nskip, *kplen, GFP_KERNEL);
if (!*kpbuf)
return -ENOMEM;
return 0;
}
static int ccp_rsa_complete(struct crypto_async_request *async_req, int ret)
{
struct akcipher_request *req = akcipher_request_cast(async_req);
struct ccp_rsa_req_ctx *rctx = akcipher_request_ctx_dma(req);
if (ret)
return ret;
req->dst_len = rctx->cmd.u.rsa.key_size >> 3;
return 0;
}
static unsigned int ccp_rsa_maxsize(struct crypto_akcipher *tfm)
{
struct ccp_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
return ctx->u.rsa.n_len;
}
static int ccp_rsa_crypt(struct akcipher_request *req, bool encrypt)
{
struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
struct ccp_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
struct ccp_rsa_req_ctx *rctx = akcipher_request_ctx_dma(req);
int ret = 0;
memset(&rctx->cmd, 0, sizeof(rctx->cmd));
INIT_LIST_HEAD(&rctx->cmd.entry);
rctx->cmd.engine = CCP_ENGINE_RSA;
rctx->cmd.u.rsa.key_size = ctx->u.rsa.key_len;
if (encrypt) {
rctx->cmd.u.rsa.exp = &ctx->u.rsa.e_sg;
rctx->cmd.u.rsa.exp_len = ctx->u.rsa.e_len;
} else {
rctx->cmd.u.rsa.exp = &ctx->u.rsa.d_sg;
rctx->cmd.u.rsa.exp_len = ctx->u.rsa.d_len;
}
rctx->cmd.u.rsa.mod = &ctx->u.rsa.n_sg;
rctx->cmd.u.rsa.mod_len = ctx->u.rsa.n_len;
rctx->cmd.u.rsa.src = req->src;
rctx->cmd.u.rsa.src_len = req->src_len;
rctx->cmd.u.rsa.dst = req->dst;
ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
return ret;
}
static int ccp_rsa_encrypt(struct akcipher_request *req)
{
return ccp_rsa_crypt(req, true);
}
static int ccp_rsa_decrypt(struct akcipher_request *req)
{
return ccp_rsa_crypt(req, false);
}
static int ccp_check_key_length(unsigned int len)
{
if (len < 8 || len > 4096)
return -EINVAL;
return 0;
}
static void ccp_rsa_free_key_bufs(struct ccp_ctx *ctx)
{
kfree_sensitive(ctx->u.rsa.e_buf);
ctx->u.rsa.e_buf = NULL;
ctx->u.rsa.e_len = 0;
kfree_sensitive(ctx->u.rsa.n_buf);
ctx->u.rsa.n_buf = NULL;
ctx->u.rsa.n_len = 0;
kfree_sensitive(ctx->u.rsa.d_buf);
ctx->u.rsa.d_buf = NULL;
ctx->u.rsa.d_len = 0;
}
static int ccp_rsa_setkey(struct crypto_akcipher *tfm, const void *key,
unsigned int keylen, bool private)
{
struct ccp_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
struct rsa_key raw_key;
int ret;
ccp_rsa_free_key_bufs(ctx);
memset(&raw_key, 0, sizeof(raw_key));
if (private)
ret = rsa_parse_priv_key(&raw_key, key, keylen);
else
ret = rsa_parse_pub_key(&raw_key, key, keylen);
if (ret)
goto n_key;
ret = ccp_copy_and_save_keypart(&ctx->u.rsa.n_buf, &ctx->u.rsa.n_len,
raw_key.n, raw_key.n_sz);
if (ret)
goto key_err;
sg_init_one(&ctx->u.rsa.n_sg, ctx->u.rsa.n_buf, ctx->u.rsa.n_len);
ctx->u.rsa.key_len = ctx->u.rsa.n_len << 3;
if (ccp_check_key_length(ctx->u.rsa.key_len)) {
ret = -EINVAL;
goto key_err;
}
ret = ccp_copy_and_save_keypart(&ctx->u.rsa.e_buf, &ctx->u.rsa.e_len,
raw_key.e, raw_key.e_sz);
if (ret)
goto key_err;
sg_init_one(&ctx->u.rsa.e_sg, ctx->u.rsa.e_buf, ctx->u.rsa.e_len);
if (private) {
ret = ccp_copy_and_save_keypart(&ctx->u.rsa.d_buf,
&ctx->u.rsa.d_len,
raw_key.d, raw_key.d_sz);
if (ret)
goto key_err;
sg_init_one(&ctx->u.rsa.d_sg,
ctx->u.rsa.d_buf, ctx->u.rsa.d_len);
}
return 0;
key_err:
ccp_rsa_free_key_bufs(ctx);
n_key:
return ret;
}
static int ccp_rsa_setprivkey(struct crypto_akcipher *tfm, const void *key,
unsigned int keylen)
{
return ccp_rsa_setkey(tfm, key, keylen, true);
}
static int ccp_rsa_setpubkey(struct crypto_akcipher *tfm, const void *key,
unsigned int keylen)
{
return ccp_rsa_setkey(tfm, key, keylen, false);
}
static int ccp_rsa_init_tfm(struct crypto_akcipher *tfm)
{
struct ccp_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
akcipher_set_reqsize_dma(tfm, sizeof(struct ccp_rsa_req_ctx));
ctx->complete = ccp_rsa_complete;
return 0;
}
static void ccp_rsa_exit_tfm(struct crypto_akcipher *tfm)
{
struct ccp_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
ccp_rsa_free_key_bufs(ctx);
}
static struct akcipher_alg ccp_rsa_defaults = {
.encrypt = ccp_rsa_encrypt,
.decrypt = ccp_rsa_decrypt,
.set_pub_key = ccp_rsa_setpubkey,
.set_priv_key = ccp_rsa_setprivkey,
.max_size = ccp_rsa_maxsize,
.init = ccp_rsa_init_tfm,
.exit = ccp_rsa_exit_tfm,
.base = {
.cra_name = "rsa",
.cra_driver_name = "rsa-ccp",
.cra_priority = CCP_CRA_PRIORITY,
.cra_module = THIS_MODULE,
.cra_ctxsize = 2 * sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
},
};
struct ccp_rsa_def {
unsigned int version;
const char *name;
const char *driver_name;
unsigned int reqsize;
struct akcipher_alg *alg_defaults;
};
static struct ccp_rsa_def rsa_algs[] = {
{
.version = CCP_VERSION(3, 0),
.name = "rsa",
.driver_name = "rsa-ccp",
.reqsize = sizeof(struct ccp_rsa_req_ctx),
.alg_defaults = &ccp_rsa_defaults,
}
};
static int ccp_register_rsa_alg(struct list_head *head,
const struct ccp_rsa_def *def)
{
struct ccp_crypto_akcipher_alg *ccp_alg;
struct akcipher_alg *alg;
int ret;
ccp_alg = kzalloc_obj(*ccp_alg);
if (!ccp_alg)
return -ENOMEM;
INIT_LIST_HEAD(&ccp_alg->entry);
alg = &ccp_alg->alg;
*alg = *def->alg_defaults;
strscpy(alg->base.cra_name, def->name);
strscpy(alg->base.cra_driver_name, def->driver_name);
ret = crypto_register_akcipher(alg);
if (ret) {
pr_err("%s akcipher algorithm registration error (%d)\n",
alg->base.cra_name, ret);
kfree(ccp_alg);
return ret;
}
list_add(&ccp_alg->entry, head);
return 0;
}
int ccp_register_rsa_algs(struct list_head *head)
{
int i, ret;
unsigned int ccpversion = ccp_version();
for (i = 0; i < ARRAY_SIZE(rsa_algs); i++) {
if (rsa_algs[i].version > ccpversion)
continue;
ret = ccp_register_rsa_alg(head, &rsa_algs[i]);
if (ret)
return ret;
}
return 0;
}
