nx-aes-ctr.c

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#include <crypto/aes.h>
#include <crypto/ctr.h>
#include <crypto/algapi.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/crypto.h>
#include <asm/vio.h>

#include "nx_csbcpb.h"
#include "nx.h"


static int ctr_aes_nx_set_key(struct crypto_tfm *tfm,
                  const u8          *in_key,
                  unsigned int       key_len)
{
    struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
    struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;

    nx_ctx_init(nx_ctx, HCOP_FC_AES);

    switch (key_len) {
    case AES_KEYSIZE_128:
        NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
        nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
        break;
    case AES_KEYSIZE_192:
        NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
        nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
        break;
    case AES_KEYSIZE_256:
        NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
        nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
        break;
    default:
        return -EINVAL;
    }

    csbcpb->cpb.hdr.mode = NX_MODE_AES_CTR;
    memcpy(csbcpb->cpb.aes_ctr.key, in_key, key_len);

    return 0;
}

static int ctr3686_aes_nx_set_key(struct crypto_tfm *tfm,
                  const u8          *in_key,
                  unsigned int       key_len)
{
    struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);

    if (key_len < CTR_RFC3686_NONCE_SIZE)
        return -EINVAL;

    memcpy(nx_ctx->priv.ctr.iv,
           in_key + key_len - CTR_RFC3686_NONCE_SIZE,
           CTR_RFC3686_NONCE_SIZE);

    key_len -= CTR_RFC3686_NONCE_SIZE;

    return ctr_aes_nx_set_key(tfm, in_key, key_len);
}

static int ctr_aes_nx_crypt(struct blkcipher_desc *desc,
                struct scatterlist    *dst,
                struct scatterlist    *src,
                unsigned int           nbytes)
{
    struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm);
    struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
    int rc;

    if (nbytes > nx_ctx->ap->databytelen)
        return -EINVAL;

    rc = nx_build_sg_lists(nx_ctx, desc, dst, src, nbytes,
                   csbcpb->cpb.aes_ctr.iv);
    if (rc)
        goto out;

    if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
        rc = -EINVAL;
        goto out;
    }

    rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
               desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
    if (rc)
        goto out;

    atomic_inc(&(nx_ctx->stats->aes_ops));
    atomic64_add(csbcpb->csb.processed_byte_count,
             &(nx_ctx->stats->aes_bytes));
out:
    return rc;
}

static int ctr3686_aes_nx_crypt(struct blkcipher_desc *desc,
                struct scatterlist    *dst,
                struct scatterlist    *src,
                unsigned int           nbytes)
{
    struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm);
    u8 *iv = nx_ctx->priv.ctr.iv;

    memcpy(iv + CTR_RFC3686_NONCE_SIZE,
           desc->info, CTR_RFC3686_IV_SIZE);
    iv[15] = 1;

    desc->info = nx_ctx->priv.ctr.iv;

    return ctr_aes_nx_crypt(desc, dst, src, nbytes);
}

struct crypto_alg nx_ctr_aes_alg = {
    .cra_name        = "ctr(aes)",
    .cra_driver_name = "ctr-aes-nx",
    .cra_priority    = 300,
    .cra_flags       = CRYPTO_ALG_TYPE_BLKCIPHER,
    .cra_blocksize   = 1,
    .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
    .cra_type        = &crypto_blkcipher_type,
    .cra_module      = THIS_MODULE,
    .cra_init        = nx_crypto_ctx_aes_ctr_init,
    .cra_exit        = nx_crypto_ctx_exit,
    .cra_blkcipher = {
        .min_keysize = AES_MIN_KEY_SIZE,
        .max_keysize = AES_MAX_KEY_SIZE,
        .ivsize      = AES_BLOCK_SIZE,
        .setkey      = ctr_aes_nx_set_key,
        .encrypt     = ctr_aes_nx_crypt,
        .decrypt     = ctr_aes_nx_crypt,
    }
};

struct crypto_alg nx_ctr3686_aes_alg = {
    .cra_name        = "rfc3686(ctr(aes))",
    .cra_driver_name = "rfc3686-ctr-aes-nx",
    .cra_priority    = 300,
    .cra_flags       = CRYPTO_ALG_TYPE_BLKCIPHER,
    .cra_blocksize   = 1,
    .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
    .cra_type        = &crypto_blkcipher_type,
    .cra_module      = THIS_MODULE,
    .cra_init        = nx_crypto_ctx_aes_ctr_init,
    .cra_exit        = nx_crypto_ctx_exit,
    .cra_blkcipher = {
        .min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
        .max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
        .ivsize      = CTR_RFC3686_IV_SIZE,
        .geniv       = "seqiv",
        .setkey      = ctr3686_aes_nx_set_key,
        .encrypt     = ctr3686_aes_nx_crypt,
        .decrypt     = ctr3686_aes_nx_crypt,
    }
};