/** * AES GCM routines supporting the Power 7+ Nest Accelerators driver * * Copyright (C) 2012 International Business Machines Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 only. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * Author: Kent Yoder */ #include #include #include #include #include #include #include "nx_csbcpb.h" #include "nx.h" static int gcm_aes_nx_set_key(struct crypto_aead *tfm, const u8 *in_key, unsigned int key_len) { struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(tfm); struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; 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_CPB_SET_KEY_SIZE(csbcpb_aead, 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_CPB_SET_KEY_SIZE(csbcpb_aead, 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_CPB_SET_KEY_SIZE(csbcpb_aead, 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_GCM; memcpy(csbcpb->cpb.aes_gcm.key, in_key, key_len); csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_GCA; memcpy(csbcpb_aead->cpb.aes_gca.key, in_key, key_len); return 0; } static int gcm4106_aes_nx_set_key(struct crypto_aead *tfm, const u8 *in_key, unsigned int key_len) { struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(tfm); char *nonce = nx_ctx->priv.gcm.nonce; int rc; if (key_len < 4) return -EINVAL; key_len -= 4; rc = gcm_aes_nx_set_key(tfm, in_key, key_len); if (rc) goto out; memcpy(nonce, in_key + key_len, 4); out: return rc; } static int gcm4106_aes_nx_setauthsize(struct crypto_aead *tfm, unsigned int authsize) { switch (authsize) { case 8: case 12: case 16: break; default: return -EINVAL; } return 0; } static int nx_gca(struct nx_crypto_ctx *nx_ctx, struct aead_request *req, u8 *out, unsigned int assoclen) { int rc; struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; struct scatter_walk walk; struct nx_sg *nx_sg = nx_ctx->in_sg; unsigned int nbytes = assoclen; unsigned int processed = 0, to_process; unsigned int max_sg_len; if (nbytes <= AES_BLOCK_SIZE) { scatterwalk_start(&walk, req->src); scatterwalk_copychunks(out, &walk, nbytes, SCATTERWALK_FROM_SG); scatterwalk_done(&walk, SCATTERWALK_FROM_SG, 0); return 0; } NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_CONTINUATION; /* page_limit: number of sg entries that fit on one page */ max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg), nx_ctx->ap->sglen); max_sg_len = min_t(u64, max_sg_len, nx_ctx->ap->databytelen/NX_PAGE_SIZE); do { /* * to_process: the data chunk to process in this update. * This value is bound by sg list limits. */ to_process = min_t(u64, nbytes - processed, nx_ctx->ap->databytelen); to_process = min_t(u64, to_process, NX_PAGE_SIZE * (max_sg_len - 1)); nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len, req->src, processed, &to_process); if ((to_process + processed) < nbytes) NX_CPB_FDM(csbcpb_aead) |= NX_FDM_INTERMEDIATE; else NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_INTERMEDIATE; nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_sg) * sizeof(struct nx_sg); rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead, req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); if (rc) return rc; memcpy(csbcpb_aead->cpb.aes_gca.in_pat, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE); NX_CPB_FDM(csbcpb_aead) |= NX_FDM_CONTINUATION; atomic_inc(&(nx_ctx->stats->aes_ops)); atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes)); processed += to_process; } while (processed < nbytes); memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE); return rc; } static int gmac(struct aead_request *req, struct blkcipher_desc *desc, unsigned int assoclen) { int rc; struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; struct nx_sg *nx_sg; unsigned int nbytes = assoclen; unsigned int processed = 0, to_process; unsigned int max_sg_len; /* Set GMAC mode */ csbcpb->cpb.hdr.mode = NX_MODE_AES_GMAC; NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION; /* page_limit: number of sg entries that fit on one page */ max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg), nx_ctx->ap->sglen); max_sg_len = min_t(u64, max_sg_len, nx_ctx->ap->databytelen/NX_PAGE_SIZE); /* Copy IV */ memcpy(csbcpb->cpb.aes_gcm.iv_or_cnt, desc->info, AES_BLOCK_SIZE); do { /* * to_process: the data chunk to process in this update. * This value is bound by sg list limits. */ to_process = min_t(u64, nbytes - processed, nx_ctx->ap->databytelen); to_process = min_t(u64, to_process, NX_PAGE_SIZE * (max_sg_len - 1)); nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len, req->src, processed, &to_process); if ((to_process + processed) < nbytes) NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; else NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; nx_ctx->op.inlen = (nx_ctx->in_sg - nx_sg) * sizeof(struct nx_sg); csbcpb->cpb.aes_gcm.bit_length_data = 0; csbcpb->cpb.aes_gcm.bit_length_aad = 8 * nbytes; rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); if (rc) goto out; memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad, csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE); memcpy(csbcpb->cpb.aes_gcm.in_s0, csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE); NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; atomic_inc(&(nx_ctx->stats->aes_ops)); atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes)); processed += to_process; } while (processed < nbytes); out: /* Restore GCM mode */ csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; return rc; } static int gcm_empty(struct aead_request *req, struct blkcipher_desc *desc, int enc) { int rc; struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; char out[AES_BLOCK_SIZE]; struct nx_sg *in_sg, *out_sg; int len; /* For scenarios where the input message is zero length, AES CTR mode * may be used. Set the source data to be a single block (16B) of all * zeros, and set the input IV value to be the same as the GMAC IV * value. - nx_wb 4.8.1.3 */ /* Change to ECB mode */ csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB; memcpy(csbcpb->cpb.aes_ecb.key, csbcpb->cpb.aes_gcm.key, sizeof(csbcpb->cpb.aes_ecb.key)); if (enc) NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; else NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; len = AES_BLOCK_SIZE; /* Encrypt the counter/IV */ in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) desc->info, &len, nx_ctx->ap->sglen); if (len != AES_BLOCK_SIZE) return -EINVAL; len = sizeof(out); out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *) out, &len, nx_ctx->ap->sglen); if (len != sizeof(out)) return -EINVAL; nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg); nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg); 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)); /* Copy out the auth tag */ memcpy(csbcpb->cpb.aes_gcm.out_pat_or_mac, out, crypto_aead_authsize(crypto_aead_reqtfm(req))); out: /* Restore XCBC mode */ csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; /* * ECB key uses the same region that GCM AAD and counter, so it's safe * to just fill it with zeroes. */ memset(csbcpb->cpb.aes_ecb.key, 0, sizeof(csbcpb->cpb.aes_ecb.key)); return rc; } static int gcm_aes_nx_crypt(struct aead_request *req, int enc, unsigned int assoclen) { struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); struct nx_gcm_rctx *rctx = aead_request_ctx(req); struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; struct blkcipher_desc desc; unsigned int nbytes = req->cryptlen; unsigned int processed = 0, to_process; unsigned long irq_flags; int rc = -EINVAL; spin_lock_irqsave(&nx_ctx->lock, irq_flags); desc.info = rctx->iv; /* initialize the counter */ *(u32 *)(desc.info + NX_GCM_CTR_OFFSET) = 1; if (nbytes == 0) { if (assoclen == 0) rc = gcm_empty(req, &desc, enc); else rc = gmac(req, &desc, assoclen); if (rc) goto out; else goto mac; } /* Process associated data */ csbcpb->cpb.aes_gcm.bit_length_aad = assoclen * 8; if (assoclen) { rc = nx_gca(nx_ctx, req, csbcpb->cpb.aes_gcm.in_pat_or_aad, assoclen); if (rc) goto out; } /* Set flags for encryption */ NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION; if (enc) { NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; } else { NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; nbytes -= crypto_aead_authsize(crypto_aead_reqtfm(req)); } do { to_process = nbytes - processed; csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8; rc = nx_build_sg_lists(nx_ctx, &desc, req->dst, req->src, &to_process, processed + req->assoclen, csbcpb->cpb.aes_gcm.iv_or_cnt); if (rc) goto out; if ((to_process + processed) < nbytes) NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; else NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); if (rc) goto out; memcpy(desc.info, csbcpb->cpb.aes_gcm.out_cnt, AES_BLOCK_SIZE); memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad, csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE); memcpy(csbcpb->cpb.aes_gcm.in_s0, csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE); NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; atomic_inc(&(nx_ctx->stats->aes_ops)); atomic64_add(csbcpb->csb.processed_byte_count, &(nx_ctx->stats->aes_bytes)); processed += to_process; } while (processed < nbytes); mac: if (enc) { /* copy out the auth tag */ scatterwalk_map_and_copy( csbcpb->cpb.aes_gcm.out_pat_or_mac, req->dst, req->assoclen + nbytes, crypto_aead_authsize(crypto_aead_reqtfm(req)), SCATTERWALK_TO_SG); } else { u8 *itag = nx_ctx->priv.gcm.iauth_tag; u8 *otag = csbcpb->cpb.aes_gcm.out_pat_or_mac; scatterwalk_map_and_copy( itag, req->src, req->assoclen + nbytes, crypto_aead_authsize(crypto_aead_reqtfm(req)), SCATTERWALK_FROM_SG); rc = memcmp(itag, otag, crypto_aead_authsize(crypto_aead_reqtfm(req))) ? -EBADMSG : 0; } out: spin_unlock_irqrestore(&nx_ctx->lock, irq_flags); return rc; } static int gcm_aes_nx_encrypt(struct aead_request *req) { struct nx_gcm_rctx *rctx = aead_request_ctx(req); char *iv = rctx->iv; memcpy(iv, req->iv, 12); return gcm_aes_nx_crypt(req, 1, req->assoclen); } static int gcm_aes_nx_decrypt(struct aead_request *req) { struct nx_gcm_rctx *rctx = aead_request_ctx(req); char *iv = rctx->iv; memcpy(iv, req->iv, 12); return gcm_aes_nx_crypt(req, 0, req->assoclen); } static int gcm4106_aes_nx_encrypt(struct aead_request *req) { struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); struct nx_gcm_rctx *rctx = aead_request_ctx(req); char *iv = rctx->iv; char *nonce = nx_ctx->priv.gcm.nonce; memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); if (req->assoclen < 8) return -EINVAL; return gcm_aes_nx_crypt(req, 1, req->assoclen - 8); } static int gcm4106_aes_nx_decrypt(struct aead_request *req) { struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); struct nx_gcm_rctx *rctx = aead_request_ctx(req); char *iv = rctx->iv; char *nonce = nx_ctx->priv.gcm.nonce; memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); if (req->assoclen < 8) return -EINVAL; return gcm_aes_nx_crypt(req, 0, req->assoclen - 8); } /* tell the block cipher walk routines that this is a stream cipher by * setting cra_blocksize to 1. Even using blkcipher_walk_virt_block * during encrypt/decrypt doesn't solve this problem, because it calls * blkcipher_walk_done under the covers, which doesn't use walk->blocksize, * but instead uses this tfm->blocksize. */ struct aead_alg nx_gcm_aes_alg = { .base = { .cra_name = "gcm(aes)", .cra_driver_name = "gcm-aes-nx", .cra_priority = 300, .cra_blocksize = 1, .cra_ctxsize = sizeof(struct nx_crypto_ctx), .cra_module = THIS_MODULE, }, .init = nx_crypto_ctx_aes_gcm_init, .exit = nx_crypto_ctx_aead_exit, .ivsize = 12, .maxauthsize = AES_BLOCK_SIZE, .setkey = gcm_aes_nx_set_key, .encrypt = gcm_aes_nx_encrypt, .decrypt = gcm_aes_nx_decrypt, }; struct aead_alg nx_gcm4106_aes_alg = { .base = { .cra_name = "rfc4106(gcm(aes))", .cra_driver_name = "rfc4106-gcm-aes-nx", .cra_priority = 300, .cra_blocksize = 1, .cra_ctxsize = sizeof(struct nx_crypto_ctx), .cra_module = THIS_MODULE, }, .init = nx_crypto_ctx_aes_gcm_init, .exit = nx_crypto_ctx_aead_exit, .ivsize = 8, .maxauthsize = AES_BLOCK_SIZE, .setkey = gcm4106_aes_nx_set_key, .setauthsize = gcm4106_aes_nx_setauthsize, .encrypt = gcm4106_aes_nx_encrypt, .decrypt = gcm4106_aes_nx_decrypt, };