/* * AMD Cryptographic Coprocessor (CCP) SHA crypto API support * * Copyright (C) 2013 Advanced Micro Devices, Inc. * * Author: Tom Lendacky <thomas.lendacky@amd.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/module.h> #include <linux/sched.h> #include <linux/delay.h> #include <linux/scatterlist.h> #include <linux/crypto.h> #include <crypto/algapi.h> #include <crypto/hash.h> #include <crypto/internal/hash.h> #include <crypto/sha.h> #include <crypto/scatterwalk.h> #include "ccp-crypto.h" static int ccp_sha_complete(struct crypto_async_request *async_req, int ret) { struct ahash_request *req = ahash_request_cast(async_req); struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); unsigned int digest_size = crypto_ahash_digestsize(tfm); if (ret) goto e_free; if (rctx->hash_rem) { /* Save remaining data to buffer */ unsigned int offset = rctx->nbytes - rctx->hash_rem; scatterwalk_map_and_copy(rctx->buf, rctx->src, offset, rctx->hash_rem, 0); rctx->buf_count = rctx->hash_rem; } else rctx->buf_count = 0; /* Update result area if supplied */ if (req->result) memcpy(req->result, rctx->ctx, digest_size); e_free: sg_free_table(&rctx->data_sg); return ret; } static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes, unsigned int final) { struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); struct scatterlist *sg; unsigned int block_size = crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); unsigned int sg_count; gfp_t gfp; u64 len; int ret; len = (u64)rctx->buf_count + (u64)nbytes; if (!final && (len <= block_size)) { scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src, 0, nbytes, 0); rctx->buf_count += nbytes; return 0; } rctx->src = req->src; rctx->nbytes = nbytes; rctx->final = final; rctx->hash_rem = final ? 0 : len & (block_size - 1); rctx->hash_cnt = len - rctx->hash_rem; if (!final && !rctx->hash_rem) { /* CCP can't do zero length final, so keep some data around */ rctx->hash_cnt -= block_size; rctx->hash_rem = block_size; } /* Initialize the context scatterlist */ sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx)); sg = NULL; if (rctx->buf_count && nbytes) { /* Build the data scatterlist table - allocate enough entries * for both data pieces (buffer and input data) */ gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL : GFP_ATOMIC; sg_count = sg_nents(req->src) + 1; ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp); if (ret) return ret; sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg); sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src); sg_mark_end(sg); sg = rctx->data_sg.sgl; } else if (rctx->buf_count) { sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); sg = &rctx->buf_sg; } else if (nbytes) { sg = req->src; } rctx->msg_bits += (rctx->hash_cnt << 3); /* Total in bits */ memset(&rctx->cmd, 0, sizeof(rctx->cmd)); INIT_LIST_HEAD(&rctx->cmd.entry); rctx->cmd.engine = CCP_ENGINE_SHA; rctx->cmd.u.sha.type = rctx->type; rctx->cmd.u.sha.ctx = &rctx->ctx_sg; rctx->cmd.u.sha.ctx_len = sizeof(rctx->ctx); rctx->cmd.u.sha.src = sg; rctx->cmd.u.sha.src_len = rctx->hash_cnt; rctx->cmd.u.sha.opad = ctx->u.sha.key_len ? &ctx->u.sha.opad_sg : NULL; rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ? ctx->u.sha.opad_count : 0; rctx->cmd.u.sha.first = rctx->first; rctx->cmd.u.sha.final = rctx->final; rctx->cmd.u.sha.msg_bits = rctx->msg_bits; rctx->first = 0; ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd); return ret; } static int ccp_sha_init(struct ahash_request *req) { struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm)); unsigned int block_size = crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); memset(rctx, 0, sizeof(*rctx)); rctx->type = alg->type; rctx->first = 1; if (ctx->u.sha.key_len) { /* Buffer the HMAC key for first update */ memcpy(rctx->buf, ctx->u.sha.ipad, block_size); rctx->buf_count = block_size; } return 0; } static int ccp_sha_update(struct ahash_request *req) { return ccp_do_sha_update(req, req->nbytes, 0); } static int ccp_sha_final(struct ahash_request *req) { return ccp_do_sha_update(req, 0, 1); } static int ccp_sha_finup(struct ahash_request *req) { return ccp_do_sha_update(req, req->nbytes, 1); } static int ccp_sha_digest(struct ahash_request *req) { int ret; ret = ccp_sha_init(req); if (ret) return ret; return ccp_sha_finup(req); } static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key, unsigned int key_len) { struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm)); struct crypto_shash *shash = ctx->u.sha.hmac_tfm; SHASH_DESC_ON_STACK(sdesc, shash); unsigned int block_size = crypto_shash_blocksize(shash); unsigned int digest_size = crypto_shash_digestsize(shash); int i, ret; /* Set to zero until complete */ ctx->u.sha.key_len = 0; /* Clear key area to provide zero padding for keys smaller * than the block size */ memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key)); if (key_len > block_size) { /* Must hash the input key */ sdesc->tfm = shash; sdesc->flags = crypto_ahash_get_flags(tfm) & CRYPTO_TFM_REQ_MAY_SLEEP; ret = crypto_shash_digest(sdesc, key, key_len, ctx->u.sha.key); if (ret) { crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); return -EINVAL; } key_len = digest_size; } else memcpy(ctx->u.sha.key, key, key_len); for (i = 0; i < block_size; i++) { ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36; ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c; } sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size); ctx->u.sha.opad_count = block_size; ctx->u.sha.key_len = key_len; return 0; } static int ccp_sha_cra_init(struct crypto_tfm *tfm) { struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); struct crypto_ahash *ahash = __crypto_ahash_cast(tfm); ctx->complete = ccp_sha_complete; ctx->u.sha.key_len = 0; crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx)); return 0; } static void ccp_sha_cra_exit(struct crypto_tfm *tfm) { } static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm) { struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm); struct crypto_shash *hmac_tfm; hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0); if (IS_ERR(hmac_tfm)) { pr_warn("could not load driver %s need for HMAC support\n", alg->child_alg); return PTR_ERR(hmac_tfm); } ctx->u.sha.hmac_tfm = hmac_tfm; return ccp_sha_cra_init(tfm); } static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm) { struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); if (ctx->u.sha.hmac_tfm) crypto_free_shash(ctx->u.sha.hmac_tfm); ccp_sha_cra_exit(tfm); } struct ccp_sha_def { const char *name; const char *drv_name; enum ccp_sha_type type; u32 digest_size; u32 block_size; }; static struct ccp_sha_def sha_algs[] = { { .name = "sha1", .drv_name = "sha1-ccp", .type = CCP_SHA_TYPE_1, .digest_size = SHA1_DIGEST_SIZE, .block_size = SHA1_BLOCK_SIZE, }, { .name = "sha224", .drv_name = "sha224-ccp", .type = CCP_SHA_TYPE_224, .digest_size = SHA224_DIGEST_SIZE, .block_size = SHA224_BLOCK_SIZE, }, { .name = "sha256", .drv_name = "sha256-ccp", .type = CCP_SHA_TYPE_256, .digest_size = SHA256_DIGEST_SIZE, .block_size = SHA256_BLOCK_SIZE, }, }; static int ccp_register_hmac_alg(struct list_head *head, const struct ccp_sha_def *def, const struct ccp_crypto_ahash_alg *base_alg) { struct ccp_crypto_ahash_alg *ccp_alg; struct ahash_alg *alg; struct hash_alg_common *halg; struct crypto_alg *base; int ret; ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); if (!ccp_alg) return -ENOMEM; /* Copy the base algorithm and only change what's necessary */ *ccp_alg = *base_alg; INIT_LIST_HEAD(&ccp_alg->entry); strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME); alg = &ccp_alg->alg; alg->setkey = ccp_sha_setkey; halg = &alg->halg; base = &halg->base; snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name); snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s", def->drv_name); base->cra_init = ccp_hmac_sha_cra_init; base->cra_exit = ccp_hmac_sha_cra_exit; ret = crypto_register_ahash(alg); if (ret) { pr_err("%s ahash algorithm registration error (%d)\n", base->cra_name, ret); kfree(ccp_alg); return ret; } list_add(&ccp_alg->entry, head); return ret; } static int ccp_register_sha_alg(struct list_head *head, const struct ccp_sha_def *def) { struct ccp_crypto_ahash_alg *ccp_alg; struct ahash_alg *alg; struct hash_alg_common *halg; struct crypto_alg *base; int ret; ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); if (!ccp_alg) return -ENOMEM; INIT_LIST_HEAD(&ccp_alg->entry); ccp_alg->type = def->type; alg = &ccp_alg->alg; alg->init = ccp_sha_init; alg->update = ccp_sha_update; alg->final = ccp_sha_final; alg->finup = ccp_sha_finup; alg->digest = ccp_sha_digest; halg = &alg->halg; halg->digestsize = def->digest_size; base = &halg->base; snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name); snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s", def->drv_name); base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC | CRYPTO_ALG_KERN_DRIVER_ONLY | CRYPTO_ALG_NEED_FALLBACK; base->cra_blocksize = def->block_size; base->cra_ctxsize = sizeof(struct ccp_ctx); base->cra_priority = CCP_CRA_PRIORITY; base->cra_type = &crypto_ahash_type; base->cra_init = ccp_sha_cra_init; base->cra_exit = ccp_sha_cra_exit; base->cra_module = THIS_MODULE; ret = crypto_register_ahash(alg); if (ret) { pr_err("%s ahash algorithm registration error (%d)\n", base->cra_name, ret); kfree(ccp_alg); return ret; } list_add(&ccp_alg->entry, head); ret = ccp_register_hmac_alg(head, def, ccp_alg); return ret; } int ccp_register_sha_algs(struct list_head *head) { int i, ret; for (i = 0; i < ARRAY_SIZE(sha_algs); i++) { ret = ccp_register_sha_alg(head, &sha_algs[i]); if (ret) return ret; } return 0; }