From cdcecfd9991fe9aac8160a9731b0ffd1e702d19d Mon Sep 17 00:00:00 2001 From: Danny Tsen Date: Mon, 20 Feb 2023 22:40:16 -0500 Subject: [PATCH] crypto: p10-aes-gcm - Glue code for AES/GCM stitched implementation Signed-off-by: Danny Tsen Signed-off-by: Herbert Xu --- arch/powerpc/crypto/aes-gcm-p10-glue.c | 345 +++++++++++++++++++++++++++++++++ 1 file changed, 345 insertions(+) create mode 100644 arch/powerpc/crypto/aes-gcm-p10-glue.c diff --git a/arch/powerpc/crypto/aes-gcm-p10-glue.c b/arch/powerpc/crypto/aes-gcm-p10-glue.c new file mode 100644 index 0000000..c95f5b7 --- /dev/null +++ b/arch/powerpc/crypto/aes-gcm-p10-glue.c @@ -0,0 +1,345 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Glue code for accelerated AES-GCM stitched implementation for ppc64le. + * + * Copyright 2022- IBM Inc. All rights reserved + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define PPC_MODULE_FEATURE_P10 (32 + ilog2(PPC_FEATURE2_ARCH_3_1)) +#define PPC_ALIGN 16 +#define GCM_IV_SIZE 12 + +MODULE_DESCRIPTION("PPC64le AES-GCM with Stitched implementation"); +MODULE_AUTHOR("Danny Tsen aadLen = alen; + i = alen & ~0xf; + if (i) { + gcm_ghash_p8(nXi, hash->Htable+32, aad, i); + aad += i; + alen -= i; + } + if (alen) { + for (i = 0; i < alen; i++) + nXi[i] ^= aad[i]; + + memset(gctx->aad_hash, 0, 16); + gcm_ghash_p8(gctx->aad_hash, hash->Htable+32, nXi, 16); + } else { + memcpy(gctx->aad_hash, nXi, 16); + } + + memcpy(hash->Htable, gctx->aad_hash, 16); +} + +static void gcmp10_init(struct gcm_ctx *gctx, u8 *iv, unsigned char *rdkey, + struct Hash_ctx *hash, u8 *assoc, unsigned int assoclen) +{ + __be32 counter = cpu_to_be32(1); + + aes_p8_encrypt(hash->H, hash->H, rdkey); + set_subkey(hash->H); + gcm_init_htable(hash->Htable+32, hash->H); + + *((__be32 *)(iv+12)) = counter; + + gctx->Plen = 0; + + /* + * Encrypt counter vector as iv tag and increment counter. + */ + aes_p8_encrypt(iv, gctx->ivtag, rdkey); + + counter = cpu_to_be32(2); + *((__be32 *)(iv+12)) = counter; + memcpy(gctx->iv, iv, 16); + + gctx->aadLen = assoclen; + memset(gctx->aad_hash, 0, 16); + if (assoclen) + set_aad(gctx, hash, assoc, assoclen); +} + +static void finish_tag(struct gcm_ctx *gctx, struct Hash_ctx *hash, int len) +{ + int i; + unsigned char len_ac[16 + PPC_ALIGN]; + unsigned char *aclen = PTR_ALIGN((void *)len_ac, PPC_ALIGN); + __be64 clen = cpu_to_be64(len << 3); + __be64 alen = cpu_to_be64(gctx->aadLen << 3); + + if (len == 0 && gctx->aadLen == 0) { + memcpy(hash->Htable, gctx->ivtag, 16); + return; + } + + /* + * Len is in bits. + */ + *((__be64 *)(aclen)) = alen; + *((__be64 *)(aclen+8)) = clen; + + /* + * hash (AAD len and len) + */ + gcm_ghash_p8(hash->Htable, hash->Htable+32, aclen, 16); + + for (i = 0; i < 16; i++) + hash->Htable[i] ^= gctx->ivtag[i]; +} + +static int set_authsize(struct crypto_aead *tfm, unsigned int authsize) +{ + switch (authsize) { + case 4: + case 8: + case 12: + case 13: + case 14: + case 15: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + +static int p10_aes_gcm_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct crypto_tfm *tfm = crypto_aead_tfm(aead); + struct p10_aes_gcm_ctx *ctx = crypto_tfm_ctx(tfm); + int ret; + + vsx_begin(); + ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); + vsx_end(); + + return ret ? -EINVAL : 0; +} + +static int p10_aes_gcm_crypt(struct aead_request *req, int enc) +{ + struct crypto_tfm *tfm = req->base.tfm; + struct p10_aes_gcm_ctx *ctx = crypto_tfm_ctx(tfm); + u8 databuf[sizeof(struct gcm_ctx) + PPC_ALIGN]; + struct gcm_ctx *gctx = PTR_ALIGN((void *)databuf, PPC_ALIGN); + u8 hashbuf[sizeof(struct Hash_ctx) + PPC_ALIGN]; + struct Hash_ctx *hash = PTR_ALIGN((void *)hashbuf, PPC_ALIGN); + struct scatter_walk assoc_sg_walk; + struct skcipher_walk walk; + u8 *assocmem = NULL; + u8 *assoc; + unsigned int assoclen = req->assoclen; + unsigned int cryptlen = req->cryptlen; + unsigned char ivbuf[AES_BLOCK_SIZE+PPC_ALIGN]; + unsigned char *iv = PTR_ALIGN((void *)ivbuf, PPC_ALIGN); + int ret; + unsigned long auth_tag_len = crypto_aead_authsize(__crypto_aead_cast(tfm)); + u8 otag[16]; + int total_processed = 0; + + memset(databuf, 0, sizeof(databuf)); + memset(hashbuf, 0, sizeof(hashbuf)); + memset(ivbuf, 0, sizeof(ivbuf)); + memcpy(iv, req->iv, GCM_IV_SIZE); + + /* Linearize assoc, if not already linear */ + if (req->src->length >= assoclen && req->src->length) { + scatterwalk_start(&assoc_sg_walk, req->src); + assoc = scatterwalk_map(&assoc_sg_walk); + } else { + gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? + GFP_KERNEL : GFP_ATOMIC; + + /* assoc can be any length, so must be on heap */ + assocmem = kmalloc(assoclen, flags); + if (unlikely(!assocmem)) + return -ENOMEM; + assoc = assocmem; + + scatterwalk_map_and_copy(assoc, req->src, 0, assoclen, 0); + } + + vsx_begin(); + gcmp10_init(gctx, iv, (unsigned char *) &ctx->enc_key, hash, assoc, assoclen); + vsx_end(); + + if (!assocmem) + scatterwalk_unmap(assoc); + else + kfree(assocmem); + + if (enc) + ret = skcipher_walk_aead_encrypt(&walk, req, false); + else + ret = skcipher_walk_aead_decrypt(&walk, req, false); + if (ret) + return ret; + + while (walk.nbytes > 0 && ret == 0) { + + vsx_begin(); + if (enc) + aes_p10_gcm_encrypt(walk.src.virt.addr, + walk.dst.virt.addr, + walk.nbytes, + &ctx->enc_key, gctx->iv, hash->Htable); + else + aes_p10_gcm_decrypt(walk.src.virt.addr, + walk.dst.virt.addr, + walk.nbytes, + &ctx->enc_key, gctx->iv, hash->Htable); + vsx_end(); + + total_processed += walk.nbytes; + ret = skcipher_walk_done(&walk, 0); + } + + if (ret) + return ret; + + /* Finalize hash */ + vsx_begin(); + finish_tag(gctx, hash, total_processed); + vsx_end(); + + /* copy Xi to end of dst */ + if (enc) + scatterwalk_map_and_copy(hash->Htable, req->dst, req->assoclen + cryptlen, + auth_tag_len, 1); + else { + scatterwalk_map_and_copy(otag, req->src, + req->assoclen + cryptlen - auth_tag_len, + auth_tag_len, 0); + + if (crypto_memneq(otag, hash->Htable, auth_tag_len)) { + memzero_explicit(hash->Htable, 16); + return -EBADMSG; + } + } + + return 0; +} + +static int p10_aes_gcm_encrypt(struct aead_request *req) +{ + return p10_aes_gcm_crypt(req, 1); +} + +static int p10_aes_gcm_decrypt(struct aead_request *req) +{ + return p10_aes_gcm_crypt(req, 0); +} + +static struct aead_alg gcm_aes_alg = { + .ivsize = GCM_IV_SIZE, + .maxauthsize = 16, + + .setauthsize = set_authsize, + .setkey = p10_aes_gcm_setkey, + .encrypt = p10_aes_gcm_encrypt, + .decrypt = p10_aes_gcm_decrypt, + + .base.cra_name = "gcm(aes)", + .base.cra_driver_name = "aes_gcm_p10", + .base.cra_priority = 2100, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct p10_aes_gcm_ctx), + .base.cra_module = THIS_MODULE, +}; + +static int __init p10_init(void) +{ + return crypto_register_aead(&gcm_aes_alg); +} + +static void __exit p10_exit(void) +{ + crypto_unregister_aead(&gcm_aes_alg); +} + +module_cpu_feature_match(PPC_MODULE_FEATURE_P10, p10_init); +module_exit(p10_exit); -- 2.7.4