diff options
Diffstat (limited to 'drivers/crypto/sunxi-ss/sun4i-ss-hash.c')
| -rw-r--r-- | drivers/crypto/sunxi-ss/sun4i-ss-hash.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-hash.c b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c new file mode 100644 index 000000000..ff8031498 --- /dev/null +++ b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c @@ -0,0 +1,492 @@ +/* + * sun4i-ss-hash.c - hardware cryptographic accelerator for Allwinner A20 SoC + * + * Copyright (C) 2013-2015 Corentin LABBE <clabbe.montjoie@gmail.com> + * + * This file add support for MD5 and SHA1. + * + * You could find the datasheet in Documentation/arm/sunxi/README + * + * 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; either version 2 of the License, or + * (at your option) any later version. + */ +#include "sun4i-ss.h" +#include <linux/scatterlist.h> + +/* This is a totally arbitrary value */ +#define SS_TIMEOUT 100 + +int sun4i_hash_crainit(struct crypto_tfm *tfm) +{ + crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm), + sizeof(struct sun4i_req_ctx)); + return 0; +} + +/* sun4i_hash_init: initialize request context */ +int sun4i_hash_init(struct ahash_request *areq) +{ + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); + struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg); + struct sun4i_ss_alg_template *algt; + struct sun4i_ss_ctx *ss; + + memset(op, 0, sizeof(struct sun4i_req_ctx)); + + algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash); + ss = algt->ss; + op->ss = algt->ss; + op->mode = algt->mode; + + return 0; +} + +int sun4i_hash_export_md5(struct ahash_request *areq, void *out) +{ + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + struct md5_state *octx = out; + int i; + + octx->byte_count = op->byte_count + op->len; + + memcpy(octx->block, op->buf, op->len); + + if (op->byte_count > 0) { + for (i = 0; i < 4; i++) + octx->hash[i] = op->hash[i]; + } else { + octx->hash[0] = SHA1_H0; + octx->hash[1] = SHA1_H1; + octx->hash[2] = SHA1_H2; + octx->hash[3] = SHA1_H3; + } + + return 0; +} + +int sun4i_hash_import_md5(struct ahash_request *areq, const void *in) +{ + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + const struct md5_state *ictx = in; + int i; + + sun4i_hash_init(areq); + + op->byte_count = ictx->byte_count & ~0x3F; + op->len = ictx->byte_count & 0x3F; + + memcpy(op->buf, ictx->block, op->len); + + for (i = 0; i < 4; i++) + op->hash[i] = ictx->hash[i]; + + return 0; +} + +int sun4i_hash_export_sha1(struct ahash_request *areq, void *out) +{ + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + struct sha1_state *octx = out; + int i; + + octx->count = op->byte_count + op->len; + + memcpy(octx->buffer, op->buf, op->len); + + if (op->byte_count > 0) { + for (i = 0; i < 5; i++) + octx->state[i] = op->hash[i]; + } else { + octx->state[0] = SHA1_H0; + octx->state[1] = SHA1_H1; + octx->state[2] = SHA1_H2; + octx->state[3] = SHA1_H3; + octx->state[4] = SHA1_H4; + } + + return 0; +} + +int sun4i_hash_import_sha1(struct ahash_request *areq, const void *in) +{ + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + const struct sha1_state *ictx = in; + int i; + + sun4i_hash_init(areq); + + op->byte_count = ictx->count & ~0x3F; + op->len = ictx->count & 0x3F; + + memcpy(op->buf, ictx->buffer, op->len); + + for (i = 0; i < 5; i++) + op->hash[i] = ictx->state[i]; + + return 0; +} + +/* + * sun4i_hash_update: update hash engine + * + * Could be used for both SHA1 and MD5 + * Write data by step of 32bits and put then in the SS. + * + * Since we cannot leave partial data and hash state in the engine, + * we need to get the hash state at the end of this function. + * We can get the hash state every 64 bytes + * + * So the first work is to get the number of bytes to write to SS modulo 64 + * The extra bytes will go to a temporary buffer op->buf storing op->len bytes + * + * So at the begin of update() + * if op->len + areq->nbytes < 64 + * => all data will be written to wait buffer (op->buf) and end=0 + * if not, write all data from op->buf to the device and position end to + * complete to 64bytes + * + * example 1: + * update1 60o => op->len=60 + * update2 60o => need one more word to have 64 bytes + * end=4 + * so write all data from op->buf and one word of SGs + * write remaining data in op->buf + * final state op->len=56 + */ +int sun4i_hash_update(struct ahash_request *areq) +{ + u32 v, ivmode = 0; + unsigned int i = 0; + /* + * i is the total bytes read from SGs, to be compared to areq->nbytes + * i is important because we cannot rely on SG length since the sum of + * SG->length could be greater than areq->nbytes + */ + + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + struct sun4i_ss_ctx *ss = op->ss; + struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); + unsigned int in_i = 0; /* advancement in the current SG */ + unsigned int end; + /* + * end is the position when we need to stop writing to the device, + * to be compared to i + */ + int in_r, err = 0; + unsigned int todo; + u32 spaces, rx_cnt = SS_RX_DEFAULT; + size_t copied = 0; + struct sg_mapping_iter mi; + + dev_dbg(ss->dev, "%s %s bc=%llu len=%u mode=%x wl=%u h0=%0x", + __func__, crypto_tfm_alg_name(areq->base.tfm), + op->byte_count, areq->nbytes, op->mode, + op->len, op->hash[0]); + + if (areq->nbytes == 0) + return 0; + + /* protect against overflow */ + if (areq->nbytes > UINT_MAX - op->len) { + dev_err(ss->dev, "Cannot process too large request\n"); + return -EINVAL; + } + + if (op->len + areq->nbytes < 64) { + /* linearize data to op->buf */ + copied = sg_pcopy_to_buffer(areq->src, sg_nents(areq->src), + op->buf + op->len, areq->nbytes, 0); + op->len += copied; + return 0; + } + + end = ((areq->nbytes + op->len) / 64) * 64 - op->len; + + if (end > areq->nbytes || areq->nbytes - end > 63) { + dev_err(ss->dev, "ERROR: Bound error %u %u\n", + end, areq->nbytes); + return -EINVAL; + } + + spin_lock_bh(&ss->slock); + + /* + * if some data have been processed before, + * we need to restore the partial hash state + */ + if (op->byte_count > 0) { + ivmode = SS_IV_ARBITRARY; + for (i = 0; i < 5; i++) + writel(op->hash[i], ss->base + SS_IV0 + i * 4); + } + /* Enable the device */ + writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL); + + i = 0; + sg_miter_start(&mi, areq->src, sg_nents(areq->src), + SG_MITER_FROM_SG | SG_MITER_ATOMIC); + sg_miter_next(&mi); + in_i = 0; + + do { + /* + * we need to linearize in two case: + * - the buffer is already used + * - the SG does not have enough byte remaining ( < 4) + */ + if (op->len > 0 || (mi.length - in_i) < 4) { + /* + * if we have entered here we have two reason to stop + * - the buffer is full + * - reach the end + */ + while (op->len < 64 && i < end) { + /* how many bytes we can read from current SG */ + in_r = min3(mi.length - in_i, end - i, + 64 - op->len); + memcpy(op->buf + op->len, mi.addr + in_i, in_r); + op->len += in_r; + i += in_r; + in_i += in_r; + if (in_i == mi.length) { + sg_miter_next(&mi); + in_i = 0; + } + } + if (op->len > 3 && (op->len % 4) == 0) { + /* write buf to the device */ + writesl(ss->base + SS_RXFIFO, op->buf, + op->len / 4); + op->byte_count += op->len; + op->len = 0; + } + } + if (mi.length - in_i > 3 && i < end) { + /* how many bytes we can read from current SG */ + in_r = min3(mi.length - in_i, areq->nbytes - i, + ((mi.length - in_i) / 4) * 4); + /* how many bytes we can write in the device*/ + todo = min3((u32)(end - i) / 4, rx_cnt, (u32)in_r / 4); + writesl(ss->base + SS_RXFIFO, mi.addr + in_i, todo); + op->byte_count += todo * 4; + i += todo * 4; + in_i += todo * 4; + rx_cnt -= todo; + if (rx_cnt == 0) { + spaces = readl(ss->base + SS_FCSR); + rx_cnt = SS_RXFIFO_SPACES(spaces); + } + if (in_i == mi.length) { + sg_miter_next(&mi); + in_i = 0; + } + } + } while (i < end); + /* final linear */ + if ((areq->nbytes - i) < 64) { + while (i < areq->nbytes && in_i < mi.length && op->len < 64) { + /* how many bytes we can read from current SG */ + in_r = min3(mi.length - in_i, areq->nbytes - i, + 64 - op->len); + memcpy(op->buf + op->len, mi.addr + in_i, in_r); + op->len += in_r; + i += in_r; + in_i += in_r; + if (in_i == mi.length) { + sg_miter_next(&mi); + in_i = 0; + } + } + } + + sg_miter_stop(&mi); + + writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL); + i = 0; + do { + v = readl(ss->base + SS_CTL); + i++; + } while (i < SS_TIMEOUT && (v & SS_DATA_END) > 0); + if (i >= SS_TIMEOUT) { + dev_err_ratelimited(ss->dev, + "ERROR: hash end timeout %d>%d ctl=%x len=%u\n", + i, SS_TIMEOUT, v, areq->nbytes); + err = -EIO; + goto release_ss; + } + + /* get the partial hash only if something was written */ + for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) + op->hash[i] = readl(ss->base + SS_MD0 + i * 4); + +release_ss: + writel(0, ss->base + SS_CTL); + spin_unlock_bh(&ss->slock); + return err; +} + +/* + * sun4i_hash_final: finalize hashing operation + * + * If we have some remaining bytes, we write them. + * Then ask the SS for finalizing the hashing operation + * + * I do not check RX FIFO size in this function since the size is 32 + * after each enabling and this function neither write more than 32 words. + */ +int sun4i_hash_final(struct ahash_request *areq) +{ + u32 v, ivmode = 0; + unsigned int i; + unsigned int j = 0; + int zeros, err = 0; + unsigned int index, padlen; + __be64 bits; + struct sun4i_req_ctx *op = ahash_request_ctx(areq); + struct sun4i_ss_ctx *ss = op->ss; + struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); + u32 bf[32]; + u32 wb = 0; + unsigned int nwait, nbw = 0; + + dev_dbg(ss->dev, "%s: byte=%llu len=%u mode=%x wl=%u h=%x", + __func__, op->byte_count, areq->nbytes, op->mode, + op->len, op->hash[0]); + + spin_lock_bh(&ss->slock); + + /* + * if we have already written something, + * restore the partial hash state + */ + if (op->byte_count > 0) { + ivmode = SS_IV_ARBITRARY; + for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) + writel(op->hash[i], ss->base + SS_IV0 + i * 4); + } + writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL); + + /* write the remaining words of the wait buffer */ + if (op->len > 0) { + nwait = op->len / 4; + if (nwait > 0) { + writesl(ss->base + SS_RXFIFO, op->buf, nwait); + op->byte_count += 4 * nwait; + } + nbw = op->len - 4 * nwait; + wb = *(u32 *)(op->buf + nwait * 4); + wb &= (0xFFFFFFFF >> (4 - nbw) * 8); + } + + /* write the remaining bytes of the nbw buffer */ + if (nbw > 0) { + wb |= ((1 << 7) << (nbw * 8)); + bf[j++] = wb; + } else { + bf[j++] = 1 << 7; + } + + /* + * number of space to pad to obtain 64o minus 8(size) minus 4 (final 1) + * I take the operations from other MD5/SHA1 implementations + */ + + /* we have already send 4 more byte of which nbw data */ + if (op->mode == SS_OP_MD5) { + index = (op->byte_count + 4) & 0x3f; + op->byte_count += nbw; + if (index > 56) + zeros = (120 - index) / 4; + else + zeros = (56 - index) / 4; + } else { + op->byte_count += nbw; + index = op->byte_count & 0x3f; + padlen = (index < 56) ? (56 - index) : ((64 + 56) - index); + zeros = (padlen - 1) / 4; + } + + memset(bf + j, 0, 4 * zeros); + j += zeros; + + /* write the length of data */ + if (op->mode == SS_OP_SHA1) { + bits = cpu_to_be64(op->byte_count << 3); + bf[j++] = bits & 0xffffffff; + bf[j++] = (bits >> 32) & 0xffffffff; + } else { + bf[j++] = (op->byte_count << 3) & 0xffffffff; + bf[j++] = (op->byte_count >> 29) & 0xffffffff; + } + writesl(ss->base + SS_RXFIFO, bf, j); + + /* Tell the SS to stop the hashing */ + writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL); + + /* + * Wait for SS to finish the hash. + * The timeout could happen only in case of bad overcloking + * or driver bug. + */ + i = 0; + do { + v = readl(ss->base + SS_CTL); + i++; + } while (i < SS_TIMEOUT && (v & SS_DATA_END) > 0); + if (i >= SS_TIMEOUT) { + dev_err_ratelimited(ss->dev, + "ERROR: hash end timeout %d>%d ctl=%x len=%u\n", + i, SS_TIMEOUT, v, areq->nbytes); + err = -EIO; + goto release_ss; + } + + /* Get the hash from the device */ + if (op->mode == SS_OP_SHA1) { + for (i = 0; i < 5; i++) { + v = cpu_to_be32(readl(ss->base + SS_MD0 + i * 4)); + memcpy(areq->result + i * 4, &v, 4); + } + } else { + for (i = 0; i < 4; i++) { + v = readl(ss->base + SS_MD0 + i * 4); + memcpy(areq->result + i * 4, &v, 4); + } + } + +release_ss: + writel(0, ss->base + SS_CTL); + spin_unlock_bh(&ss->slock); + return err; +} + +/* sun4i_hash_finup: finalize hashing operation after an update */ +int sun4i_hash_finup(struct ahash_request *areq) +{ + int err; + + err = sun4i_hash_update(areq); + if (err != 0) + return err; + + return sun4i_hash_final(areq); +} + +/* combo of init/update/final functions */ +int sun4i_hash_digest(struct ahash_request *areq) +{ + int err; + + err = sun4i_hash_init(areq); + if (err != 0) + return err; + + err = sun4i_hash_update(areq); + if (err != 0) + return err; + + return sun4i_hash_final(areq); +} |