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|
/*
* Copyright 2016 Broadcom
*
* 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 (the "GPL").
*
* 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 version 2 (GPLv2) for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 (GPLv2) along with this source code.
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include "util.h"
#include "spu.h"
#include "spum.h"
#include "cipher.h"
char *hash_alg_name[] = { "None", "md5", "sha1", "sha224", "sha256", "aes",
"sha384", "sha512", "sha3_224", "sha3_256", "sha3_384", "sha3_512" };
char *aead_alg_name[] = { "ccm(aes)", "gcm(aes)", "authenc" };
/* Assumes SPU-M messages are in big endian */
void spum_dump_msg_hdr(u8 *buf, unsigned int buf_len)
{
u8 *ptr = buf;
struct SPUHEADER *spuh = (struct SPUHEADER *)buf;
unsigned int hash_key_len = 0;
unsigned int hash_state_len = 0;
unsigned int cipher_key_len = 0;
unsigned int iv_len;
u32 pflags;
u32 cflags;
u32 ecf;
u32 cipher_alg;
u32 cipher_mode;
u32 cipher_type;
u32 hash_alg;
u32 hash_mode;
u32 hash_type;
u32 sctx_size; /* SCTX length in words */
u32 sctx_pl_len; /* SCTX payload length in bytes */
packet_log("\n");
packet_log("SPU Message header %p len: %u\n", buf, buf_len);
/* ========== Decode MH ========== */
packet_log(" MH 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
if (spuh->mh.flags & MH_SCTX_PRES)
packet_log(" SCTX present\n");
if (spuh->mh.flags & MH_BDESC_PRES)
packet_log(" BDESC present\n");
if (spuh->mh.flags & MH_MFM_PRES)
packet_log(" MFM present\n");
if (spuh->mh.flags & MH_BD_PRES)
packet_log(" BD present\n");
if (spuh->mh.flags & MH_HASH_PRES)
packet_log(" HASH present\n");
if (spuh->mh.flags & MH_SUPDT_PRES)
packet_log(" SUPDT present\n");
packet_log(" Opcode 0x%02x\n", spuh->mh.op_code);
ptr += sizeof(spuh->mh) + sizeof(spuh->emh); /* skip emh. unused */
/* ========== Decode SCTX ========== */
if (spuh->mh.flags & MH_SCTX_PRES) {
pflags = be32_to_cpu(spuh->sa.proto_flags);
packet_log(" SCTX[0] 0x%08x\n", pflags);
sctx_size = pflags & SCTX_SIZE;
packet_log(" Size %u words\n", sctx_size);
cflags = be32_to_cpu(spuh->sa.cipher_flags);
packet_log(" SCTX[1] 0x%08x\n", cflags);
packet_log(" Inbound:%lu (1:decrypt/vrfy 0:encrypt/auth)\n",
(cflags & CIPHER_INBOUND) >> CIPHER_INBOUND_SHIFT);
packet_log(" Order:%lu (1:AuthFirst 0:EncFirst)\n",
(cflags & CIPHER_ORDER) >> CIPHER_ORDER_SHIFT);
packet_log(" ICV_IS_512:%lx\n",
(cflags & ICV_IS_512) >> ICV_IS_512_SHIFT);
cipher_alg = (cflags & CIPHER_ALG) >> CIPHER_ALG_SHIFT;
cipher_mode = (cflags & CIPHER_MODE) >> CIPHER_MODE_SHIFT;
cipher_type = (cflags & CIPHER_TYPE) >> CIPHER_TYPE_SHIFT;
packet_log(" Crypto Alg:%u Mode:%u Type:%u\n",
cipher_alg, cipher_mode, cipher_type);
hash_alg = (cflags & HASH_ALG) >> HASH_ALG_SHIFT;
hash_mode = (cflags & HASH_MODE) >> HASH_MODE_SHIFT;
hash_type = (cflags & HASH_TYPE) >> HASH_TYPE_SHIFT;
packet_log(" Hash Alg:%x Mode:%x Type:%x\n",
hash_alg, hash_mode, hash_type);
packet_log(" UPDT_Offset:%u\n", cflags & UPDT_OFST);
ecf = be32_to_cpu(spuh->sa.ecf);
packet_log(" SCTX[2] 0x%08x\n", ecf);
packet_log(" WriteICV:%lu CheckICV:%lu ICV_SIZE:%u ",
(ecf & INSERT_ICV) >> INSERT_ICV_SHIFT,
(ecf & CHECK_ICV) >> CHECK_ICV_SHIFT,
(ecf & ICV_SIZE) >> ICV_SIZE_SHIFT);
packet_log("BD_SUPPRESS:%lu\n",
(ecf & BD_SUPPRESS) >> BD_SUPPRESS_SHIFT);
packet_log(" SCTX_IV:%lu ExplicitIV:%lu GenIV:%lu ",
(ecf & SCTX_IV) >> SCTX_IV_SHIFT,
(ecf & EXPLICIT_IV) >> EXPLICIT_IV_SHIFT,
(ecf & GEN_IV) >> GEN_IV_SHIFT);
packet_log("IV_OV_OFST:%lu EXP_IV_SIZE:%u\n",
(ecf & IV_OFFSET) >> IV_OFFSET_SHIFT,
ecf & EXP_IV_SIZE);
ptr += sizeof(struct SCTX);
if (hash_alg && hash_mode) {
char *name = "NONE";
switch (hash_alg) {
case HASH_ALG_MD5:
hash_key_len = 16;
name = "MD5";
break;
case HASH_ALG_SHA1:
hash_key_len = 20;
name = "SHA1";
break;
case HASH_ALG_SHA224:
hash_key_len = 28;
name = "SHA224";
break;
case HASH_ALG_SHA256:
hash_key_len = 32;
name = "SHA256";
break;
case HASH_ALG_SHA384:
hash_key_len = 48;
name = "SHA384";
break;
case HASH_ALG_SHA512:
hash_key_len = 64;
name = "SHA512";
break;
case HASH_ALG_AES:
hash_key_len = 0;
name = "AES";
break;
case HASH_ALG_NONE:
break;
}
packet_log(" Auth Key Type:%s Length:%u Bytes\n",
name, hash_key_len);
packet_dump(" KEY: ", ptr, hash_key_len);
ptr += hash_key_len;
} else if ((hash_alg == HASH_ALG_AES) &&
(hash_mode == HASH_MODE_XCBC)) {
char *name = "NONE";
switch (cipher_type) {
case CIPHER_TYPE_AES128:
hash_key_len = 16;
name = "AES128-XCBC";
break;
case CIPHER_TYPE_AES192:
hash_key_len = 24;
name = "AES192-XCBC";
break;
case CIPHER_TYPE_AES256:
hash_key_len = 32;
name = "AES256-XCBC";
break;
}
packet_log(" Auth Key Type:%s Length:%u Bytes\n",
name, hash_key_len);
packet_dump(" KEY: ", ptr, hash_key_len);
ptr += hash_key_len;
}
if (hash_alg && (hash_mode == HASH_MODE_NONE) &&
(hash_type == HASH_TYPE_UPDT)) {
char *name = "NONE";
switch (hash_alg) {
case HASH_ALG_MD5:
hash_state_len = 16;
name = "MD5";
break;
case HASH_ALG_SHA1:
hash_state_len = 20;
name = "SHA1";
break;
case HASH_ALG_SHA224:
hash_state_len = 32;
name = "SHA224";
break;
case HASH_ALG_SHA256:
hash_state_len = 32;
name = "SHA256";
break;
case HASH_ALG_SHA384:
hash_state_len = 48;
name = "SHA384";
break;
case HASH_ALG_SHA512:
hash_state_len = 64;
name = "SHA512";
break;
case HASH_ALG_AES:
hash_state_len = 0;
name = "AES";
break;
case HASH_ALG_NONE:
break;
}
packet_log(" Auth State Type:%s Length:%u Bytes\n",
name, hash_state_len);
packet_dump(" State: ", ptr, hash_state_len);
ptr += hash_state_len;
}
if (cipher_alg) {
char *name = "NONE";
switch (cipher_alg) {
case CIPHER_ALG_DES:
cipher_key_len = 8;
name = "DES";
break;
case CIPHER_ALG_3DES:
cipher_key_len = 24;
name = "3DES";
break;
case CIPHER_ALG_RC4:
cipher_key_len = 260;
name = "ARC4";
break;
case CIPHER_ALG_AES:
switch (cipher_type) {
case CIPHER_TYPE_AES128:
cipher_key_len = 16;
name = "AES128";
break;
case CIPHER_TYPE_AES192:
cipher_key_len = 24;
name = "AES192";
break;
case CIPHER_TYPE_AES256:
cipher_key_len = 32;
name = "AES256";
break;
}
break;
case CIPHER_ALG_NONE:
break;
}
packet_log(" Cipher Key Type:%s Length:%u Bytes\n",
name, cipher_key_len);
/* XTS has two keys */
if (cipher_mode == CIPHER_MODE_XTS) {
packet_dump(" KEY2: ", ptr, cipher_key_len);
ptr += cipher_key_len;
packet_dump(" KEY1: ", ptr, cipher_key_len);
ptr += cipher_key_len;
cipher_key_len *= 2;
} else {
packet_dump(" KEY: ", ptr, cipher_key_len);
ptr += cipher_key_len;
}
if (ecf & SCTX_IV) {
sctx_pl_len = sctx_size * sizeof(u32) -
sizeof(struct SCTX);
iv_len = sctx_pl_len -
(hash_key_len + hash_state_len +
cipher_key_len);
packet_log(" IV Length:%u Bytes\n", iv_len);
packet_dump(" IV: ", ptr, iv_len);
ptr += iv_len;
}
}
}
/* ========== Decode BDESC ========== */
if (spuh->mh.flags & MH_BDESC_PRES) {
#ifdef DEBUG
struct BDESC_HEADER *bdesc = (struct BDESC_HEADER *)ptr;
#endif
packet_log(" BDESC[0] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
packet_log(" OffsetMAC:%u LengthMAC:%u\n",
be16_to_cpu(bdesc->offset_mac),
be16_to_cpu(bdesc->length_mac));
ptr += sizeof(u32);
packet_log(" BDESC[1] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
packet_log(" OffsetCrypto:%u LengthCrypto:%u\n",
be16_to_cpu(bdesc->offset_crypto),
be16_to_cpu(bdesc->length_crypto));
ptr += sizeof(u32);
packet_log(" BDESC[2] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
packet_log(" OffsetICV:%u OffsetIV:%u\n",
be16_to_cpu(bdesc->offset_icv),
be16_to_cpu(bdesc->offset_iv));
ptr += sizeof(u32);
}
/* ========== Decode BD ========== */
if (spuh->mh.flags & MH_BD_PRES) {
#ifdef DEBUG
struct BD_HEADER *bd = (struct BD_HEADER *)ptr;
#endif
packet_log(" BD[0] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
packet_log(" Size:%ubytes PrevLength:%u\n",
be16_to_cpu(bd->size), be16_to_cpu(bd->prev_length));
ptr += 4;
}
/* Double check sanity */
if (buf + buf_len != ptr) {
packet_log(" Packet parsed incorrectly. ");
packet_log("buf:%p buf_len:%u buf+buf_len:%p ptr:%p\n",
buf, buf_len, buf + buf_len, ptr);
}
packet_log("\n");
}
/**
* spum_ns2_ctx_max_payload() - Determine the max length of the payload for a
* SPU message for a given cipher and hash alg context.
* @cipher_alg: The cipher algorithm
* @cipher_mode: The cipher mode
* @blocksize: The size of a block of data for this algo
*
* The max payload must be a multiple of the blocksize so that if a request is
* too large to fit in a single SPU message, the request can be broken into
* max_payload sized chunks. Each chunk must be a multiple of blocksize.
*
* Return: Max payload length in bytes
*/
u32 spum_ns2_ctx_max_payload(enum spu_cipher_alg cipher_alg,
enum spu_cipher_mode cipher_mode,
unsigned int blocksize)
{
u32 max_payload = SPUM_NS2_MAX_PAYLOAD;
u32 excess;
/* In XTS on SPU-M, we'll need to insert tweak before input data */
if (cipher_mode == CIPHER_MODE_XTS)
max_payload -= SPU_XTS_TWEAK_SIZE;
excess = max_payload % blocksize;
return max_payload - excess;
}
/**
* spum_nsp_ctx_max_payload() - Determine the max length of the payload for a
* SPU message for a given cipher and hash alg context.
* @cipher_alg: The cipher algorithm
* @cipher_mode: The cipher mode
* @blocksize: The size of a block of data for this algo
*
* The max payload must be a multiple of the blocksize so that if a request is
* too large to fit in a single SPU message, the request can be broken into
* max_payload sized chunks. Each chunk must be a multiple of blocksize.
*
* Return: Max payload length in bytes
*/
u32 spum_nsp_ctx_max_payload(enum spu_cipher_alg cipher_alg,
enum spu_cipher_mode cipher_mode,
unsigned int blocksize)
{
u32 max_payload = SPUM_NSP_MAX_PAYLOAD;
u32 excess;
/* In XTS on SPU-M, we'll need to insert tweak before input data */
if (cipher_mode == CIPHER_MODE_XTS)
max_payload -= SPU_XTS_TWEAK_SIZE;
excess = max_payload % blocksize;
return max_payload - excess;
}
/** spum_payload_length() - Given a SPU-M message header, extract the payload
* length.
* @spu_hdr: Start of SPU header
*
* Assumes just MH, EMH, BD (no SCTX, BDESC. Works for response frames.
*
* Return: payload length in bytes
*/
u32 spum_payload_length(u8 *spu_hdr)
{
struct BD_HEADER *bd;
u32 pl_len;
/* Find BD header. skip MH, EMH */
bd = (struct BD_HEADER *)(spu_hdr + 8);
pl_len = be16_to_cpu(bd->size);
return pl_len;
}
/**
* spum_response_hdr_len() - Given the length of the hash key and encryption
* key, determine the expected length of a SPU response header.
* @auth_key_len: authentication key length (bytes)
* @enc_key_len: encryption key length (bytes)
* @is_hash: true if response message is for a hash operation
*
* Return: length of SPU response header (bytes)
*/
u16 spum_response_hdr_len(u16 auth_key_len, u16 enc_key_len, bool is_hash)
{
if (is_hash)
return SPU_HASH_RESP_HDR_LEN;
else
return SPU_RESP_HDR_LEN;
}
/**
* spum_hash_pad_len() - Calculate the length of hash padding required to extend
* data to a full block size.
* @hash_alg: hash algorithm
* @hash_mode: hash mode
* @chunksize: length of data, in bytes
* @hash_block_size: size of a block of data for hash algorithm
*
* Reserve space for 1 byte (0x80) start of pad and the total length as u64
*
* Return: length of hash pad in bytes
*/
u16 spum_hash_pad_len(enum hash_alg hash_alg, enum hash_mode hash_mode,
u32 chunksize, u16 hash_block_size)
{
unsigned int length_len;
unsigned int used_space_last_block;
int hash_pad_len;
/* AES-XCBC hash requires just padding to next block boundary */
if ((hash_alg == HASH_ALG_AES) && (hash_mode == HASH_MODE_XCBC)) {
used_space_last_block = chunksize % hash_block_size;
hash_pad_len = hash_block_size - used_space_last_block;
if (hash_pad_len >= hash_block_size)
hash_pad_len -= hash_block_size;
return hash_pad_len;
}
used_space_last_block = chunksize % hash_block_size + 1;
if ((hash_alg == HASH_ALG_SHA384) || (hash_alg == HASH_ALG_SHA512))
length_len = 2 * sizeof(u64);
else
length_len = sizeof(u64);
used_space_last_block += length_len;
hash_pad_len = hash_block_size - used_space_last_block;
if (hash_pad_len < 0)
hash_pad_len += hash_block_size;
hash_pad_len += 1 + length_len;
return hash_pad_len;
}
/**
* spum_gcm_ccm_pad_len() - Determine the required length of GCM or CCM padding.
* @cipher_mode: Algo type
* @data_size: Length of plaintext (bytes)
*
* @Return: Length of padding, in bytes
*/
u32 spum_gcm_ccm_pad_len(enum spu_cipher_mode cipher_mode,
unsigned int data_size)
{
u32 pad_len = 0;
u32 m1 = SPU_GCM_CCM_ALIGN - 1;
if ((cipher_mode == CIPHER_MODE_GCM) ||
(cipher_mode == CIPHER_MODE_CCM))
pad_len = ((data_size + m1) & ~m1) - data_size;
return pad_len;
}
/**
* spum_assoc_resp_len() - Determine the size of the receive buffer required to
* catch associated data.
* @cipher_mode: cipher mode
* @assoc_len: length of associated data (bytes)
* @iv_len: length of IV (bytes)
* @is_encrypt: true if encrypting. false if decrypting.
*
* Return: length of associated data in response message (bytes)
*/
u32 spum_assoc_resp_len(enum spu_cipher_mode cipher_mode,
unsigned int assoc_len, unsigned int iv_len,
bool is_encrypt)
{
u32 buflen = 0;
u32 pad;
if (assoc_len)
buflen = assoc_len;
if (cipher_mode == CIPHER_MODE_GCM) {
/* AAD needs to be padded in responses too */
pad = spum_gcm_ccm_pad_len(cipher_mode, buflen);
buflen += pad;
}
if (cipher_mode == CIPHER_MODE_CCM) {
/*
* AAD needs to be padded in responses too
* for CCM, len + 2 needs to be 128-bit aligned.
*/
pad = spum_gcm_ccm_pad_len(cipher_mode, buflen + 2);
buflen += pad;
}
return buflen;
}
/**
* spu_aead_ivlen() - Calculate the length of the AEAD IV to be included
* in a SPU request after the AAD and before the payload.
* @cipher_mode: cipher mode
* @iv_ctr_len: initialization vector length in bytes
*
* In Linux ~4.2 and later, the assoc_data sg includes the IV. So no need
* to include the IV as a separate field in the SPU request msg.
*
* Return: Length of AEAD IV in bytes
*/
u8 spum_aead_ivlen(enum spu_cipher_mode cipher_mode, u16 iv_len)
{
return 0;
}
/**
* spum_hash_type() - Determine the type of hash operation.
* @src_sent: The number of bytes in the current request that have already
* been sent to the SPU to be hashed.
*
* We do not use HASH_TYPE_FULL for requests that fit in a single SPU message.
* Using FULL causes failures (such as when the string to be hashed is empty).
* For similar reasons, we never use HASH_TYPE_FIN. Instead, submit messages
* as INIT or UPDT and do the hash padding in sw.
*/
enum hash_type spum_hash_type(u32 src_sent)
{
return src_sent ? HASH_TYPE_UPDT : HASH_TYPE_INIT;
}
/**
* spum_digest_size() - Determine the size of a hash digest to expect the SPU to
* return.
* alg_digest_size: Number of bytes in the final digest for the given algo
* alg: The hash algorithm
* htype: Type of hash operation (init, update, full, etc)
*
* When doing incremental hashing for an algorithm with a truncated hash
* (e.g., SHA224), the SPU returns the full digest so that it can be fed back as
* a partial result for the next chunk.
*/
u32 spum_digest_size(u32 alg_digest_size, enum hash_alg alg,
enum hash_type htype)
{
u32 digestsize = alg_digest_size;
/* SPU returns complete digest when doing incremental hash and truncated
* hash algo.
*/
if ((htype == HASH_TYPE_INIT) || (htype == HASH_TYPE_UPDT)) {
if (alg == HASH_ALG_SHA224)
digestsize = SHA256_DIGEST_SIZE;
else if (alg == HASH_ALG_SHA384)
digestsize = SHA512_DIGEST_SIZE;
}
return digestsize;
}
/**
* spum_create_request() - Build a SPU request message header, up to and
* including the BD header. Construct the message starting at spu_hdr. Caller
* should allocate this buffer in DMA-able memory at least SPU_HEADER_ALLOC_LEN
* bytes long.
* @spu_hdr: Start of buffer where SPU request header is to be written
* @req_opts: SPU request message options
* @cipher_parms: Parameters related to cipher algorithm
* @hash_parms: Parameters related to hash algorithm
* @aead_parms: Parameters related to AEAD operation
* @data_size: Length of data to be encrypted or authenticated. If AEAD, does
* not include length of AAD.
* Return: the length of the SPU header in bytes. 0 if an error occurs.
*/
u32 spum_create_request(u8 *spu_hdr,
struct spu_request_opts *req_opts,
struct spu_cipher_parms *cipher_parms,
struct spu_hash_parms *hash_parms,
struct spu_aead_parms *aead_parms,
unsigned int data_size)
{
struct SPUHEADER *spuh;
struct BDESC_HEADER *bdesc;
struct BD_HEADER *bd;
u8 *ptr;
u32 protocol_bits = 0;
u32 cipher_bits = 0;
u32 ecf_bits = 0;
u8 sctx_words = 0;
unsigned int buf_len = 0;
/* size of the cipher payload */
unsigned int cipher_len = hash_parms->prebuf_len + data_size +
hash_parms->pad_len;
/* offset of prebuf or data from end of BD header */
unsigned int cipher_offset = aead_parms->assoc_size +
aead_parms->iv_len + aead_parms->aad_pad_len;
/* total size of the DB data (without STAT word padding) */
unsigned int real_db_size = spu_real_db_size(aead_parms->assoc_size,
aead_parms->iv_len,
hash_parms->prebuf_len,
data_size,
aead_parms->aad_pad_len,
aead_parms->data_pad_len,
hash_parms->pad_len);
unsigned int auth_offset = 0;
unsigned int offset_iv = 0;
/* size/offset of the auth payload */
unsigned int auth_len;
auth_len = real_db_size;
if (req_opts->is_aead && req_opts->is_inbound)
cipher_len -= hash_parms->digestsize;
if (req_opts->is_aead && req_opts->is_inbound)
auth_len -= hash_parms->digestsize;
if ((hash_parms->alg == HASH_ALG_AES) &&
(hash_parms->mode == HASH_MODE_XCBC)) {
auth_len -= hash_parms->pad_len;
cipher_len -= hash_parms->pad_len;
}
flow_log("%s()\n", __func__);
flow_log(" in:%u authFirst:%u\n",
req_opts->is_inbound, req_opts->auth_first);
flow_log(" %s. cipher alg:%u mode:%u type %u\n",
spu_alg_name(cipher_parms->alg, cipher_parms->mode),
cipher_parms->alg, cipher_parms->mode, cipher_parms->type);
flow_log(" key: %d\n", cipher_parms->key_len);
flow_dump(" key: ", cipher_parms->key_buf, cipher_parms->key_len);
flow_log(" iv: %d\n", cipher_parms->iv_len);
flow_dump(" iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
flow_log(" auth alg:%u mode:%u type %u\n",
hash_parms->alg, hash_parms->mode, hash_parms->type);
flow_log(" digestsize: %u\n", hash_parms->digestsize);
flow_log(" authkey: %d\n", hash_parms->key_len);
flow_dump(" authkey: ", hash_parms->key_buf, hash_parms->key_len);
flow_log(" assoc_size:%u\n", aead_parms->assoc_size);
flow_log(" prebuf_len:%u\n", hash_parms->prebuf_len);
flow_log(" data_size:%u\n", data_size);
flow_log(" hash_pad_len:%u\n", hash_parms->pad_len);
flow_log(" real_db_size:%u\n", real_db_size);
flow_log(" auth_offset:%u auth_len:%u cipher_offset:%u cipher_len:%u\n",
auth_offset, auth_len, cipher_offset, cipher_len);
flow_log(" aead_iv: %u\n", aead_parms->iv_len);
/* starting out: zero the header (plus some) */
ptr = spu_hdr;
memset(ptr, 0, sizeof(struct SPUHEADER));
/* format master header word */
/* Do not set the next bit even though the datasheet says to */
spuh = (struct SPUHEADER *)ptr;
ptr += sizeof(struct SPUHEADER);
buf_len += sizeof(struct SPUHEADER);
spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC;
spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES);
/* Format sctx word 0 (protocol_bits) */
sctx_words = 3; /* size in words */
/* Format sctx word 1 (cipher_bits) */
if (req_opts->is_inbound)
cipher_bits |= CIPHER_INBOUND;
if (req_opts->auth_first)
cipher_bits |= CIPHER_ORDER;
/* Set the crypto parameters in the cipher.flags */
cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT;
cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT;
cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT;
/* Set the auth parameters in the cipher.flags */
cipher_bits |= hash_parms->alg << HASH_ALG_SHIFT;
cipher_bits |= hash_parms->mode << HASH_MODE_SHIFT;
cipher_bits |= hash_parms->type << HASH_TYPE_SHIFT;
/*
* Format sctx extensions if required, and update main fields if
* required)
*/
if (hash_parms->alg) {
/* Write the authentication key material if present */
if (hash_parms->key_len) {
memcpy(ptr, hash_parms->key_buf, hash_parms->key_len);
ptr += hash_parms->key_len;
buf_len += hash_parms->key_len;
sctx_words += hash_parms->key_len / 4;
}
if ((cipher_parms->mode == CIPHER_MODE_GCM) ||
(cipher_parms->mode == CIPHER_MODE_CCM))
/* unpadded length */
offset_iv = aead_parms->assoc_size;
/* if GCM/CCM we need to write ICV into the payload */
if (!req_opts->is_inbound) {
if ((cipher_parms->mode == CIPHER_MODE_GCM) ||
(cipher_parms->mode == CIPHER_MODE_CCM))
ecf_bits |= 1 << INSERT_ICV_SHIFT;
} else {
ecf_bits |= CHECK_ICV;
}
/* Inform the SPU of the ICV size (in words) */
if (hash_parms->digestsize == 64)
cipher_bits |= ICV_IS_512;
else
ecf_bits |=
(hash_parms->digestsize / 4) << ICV_SIZE_SHIFT;
}
if (req_opts->bd_suppress)
ecf_bits |= BD_SUPPRESS;
/* copy the encryption keys in the SAD entry */
if (cipher_parms->alg) {
if (cipher_parms->key_len) {
memcpy(ptr, cipher_parms->key_buf,
cipher_parms->key_len);
ptr += cipher_parms->key_len;
buf_len += cipher_parms->key_len;
sctx_words += cipher_parms->key_len / 4;
}
/*
* if encrypting then set IV size, use SCTX IV unless no IV
* given here
*/
if (cipher_parms->iv_buf && cipher_parms->iv_len) {
/* Use SCTX IV */
ecf_bits |= SCTX_IV;
/* cipher iv provided so put it in here */
memcpy(ptr, cipher_parms->iv_buf, cipher_parms->iv_len);
ptr += cipher_parms->iv_len;
buf_len += cipher_parms->iv_len;
sctx_words += cipher_parms->iv_len / 4;
}
}
/*
* RFC4543 (GMAC/ESP) requires data to be sent as part of AAD
* so we need to override the BDESC parameters.
*/
if (req_opts->is_rfc4543) {
if (req_opts->is_inbound)
data_size -= hash_parms->digestsize;
offset_iv = aead_parms->assoc_size + data_size;
cipher_len = 0;
cipher_offset = offset_iv;
auth_len = cipher_offset + aead_parms->data_pad_len;
}
/* write in the total sctx length now that we know it */
protocol_bits |= sctx_words;
/* Endian adjust the SCTX */
spuh->sa.proto_flags = cpu_to_be32(protocol_bits);
spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
spuh->sa.ecf = cpu_to_be32(ecf_bits);
/* === create the BDESC section === */
bdesc = (struct BDESC_HEADER *)ptr;
bdesc->offset_mac = cpu_to_be16(auth_offset);
bdesc->length_mac = cpu_to_be16(auth_len);
bdesc->offset_crypto = cpu_to_be16(cipher_offset);
bdesc->length_crypto = cpu_to_be16(cipher_len);
/*
* CCM in SPU-M requires that ICV not be in same 32-bit word as data or
* padding. So account for padding as necessary.
*/
if (cipher_parms->mode == CIPHER_MODE_CCM)
auth_len += spum_wordalign_padlen(auth_len);
bdesc->offset_icv = cpu_to_be16(auth_len);
bdesc->offset_iv = cpu_to_be16(offset_iv);
ptr += sizeof(struct BDESC_HEADER);
buf_len += sizeof(struct BDESC_HEADER);
/* === no MFM section === */
/* === create the BD section === */
/* add the BD header */
bd = (struct BD_HEADER *)ptr;
bd->size = cpu_to_be16(real_db_size);
bd->prev_length = 0;
ptr += sizeof(struct BD_HEADER);
buf_len += sizeof(struct BD_HEADER);
packet_dump(" SPU request header: ", spu_hdr, buf_len);
return buf_len;
}
/**
* spum_cipher_req_init() - Build a SPU request message header, up to and
* including the BD header.
* @spu_hdr: Start of SPU request header (MH)
* @cipher_parms: Parameters that describe the cipher request
*
* Construct the message starting at spu_hdr. Caller should allocate this buffer
* in DMA-able memory at least SPU_HEADER_ALLOC_LEN bytes long.
*
* Return: the length of the SPU header in bytes. 0 if an error occurs.
*/
u16 spum_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms)
{
struct SPUHEADER *spuh;
u32 protocol_bits = 0;
u32 cipher_bits = 0;
u32 ecf_bits = 0;
u8 sctx_words = 0;
u8 *ptr = spu_hdr;
flow_log("%s()\n", __func__);
flow_log(" cipher alg:%u mode:%u type %u\n", cipher_parms->alg,
cipher_parms->mode, cipher_parms->type);
flow_log(" cipher_iv_len: %u\n", cipher_parms->iv_len);
flow_log(" key: %d\n", cipher_parms->key_len);
flow_dump(" key: ", cipher_parms->key_buf, cipher_parms->key_len);
/* starting out: zero the header (plus some) */
memset(spu_hdr, 0, sizeof(struct SPUHEADER));
ptr += sizeof(struct SPUHEADER);
/* format master header word */
/* Do not set the next bit even though the datasheet says to */
spuh = (struct SPUHEADER *)spu_hdr;
spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC;
spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES);
/* Format sctx word 0 (protocol_bits) */
sctx_words = 3; /* size in words */
/* copy the encryption keys in the SAD entry */
if (cipher_parms->alg) {
if (cipher_parms->key_len) {
ptr += cipher_parms->key_len;
sctx_words += cipher_parms->key_len / 4;
}
/*
* if encrypting then set IV size, use SCTX IV unless no IV
* given here
*/
if (cipher_parms->iv_len) {
/* Use SCTX IV */
ecf_bits |= SCTX_IV;
ptr += cipher_parms->iv_len;
sctx_words += cipher_parms->iv_len / 4;
}
}
/* Set the crypto parameters in the cipher.flags */
cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT;
cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT;
cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT;
/* copy the encryption keys in the SAD entry */
if (cipher_parms->alg && cipher_parms->key_len)
memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len);
/* write in the total sctx length now that we know it */
protocol_bits |= sctx_words;
/* Endian adjust the SCTX */
spuh->sa.proto_flags = cpu_to_be32(protocol_bits);
/* Endian adjust the SCTX */
spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
spuh->sa.ecf = cpu_to_be32(ecf_bits);
packet_dump(" SPU request header: ", spu_hdr,
sizeof(struct SPUHEADER));
return sizeof(struct SPUHEADER) + cipher_parms->key_len +
cipher_parms->iv_len + sizeof(struct BDESC_HEADER) +
sizeof(struct BD_HEADER);
}
/**
* spum_cipher_req_finish() - Finish building a SPU request message header for a
* block cipher request. Assumes much of the header was already filled in at
* setkey() time in spu_cipher_req_init().
* @spu_hdr: Start of the request message header (MH field)
* @spu_req_hdr_len: Length in bytes of the SPU request header
* @isInbound: 0 encrypt, 1 decrypt
* @cipher_parms: Parameters describing cipher operation to be performed
* @update_key: If true, rewrite the cipher key in SCTX
* @data_size: Length of the data in the BD field
*
* Assumes much of the header was already filled in at setkey() time in
* spum_cipher_req_init().
* spum_cipher_req_init() fills in the encryption key. For RC4, when submitting
* a request for a non-first chunk, we use the 260-byte SUPDT field from the
* previous response as the key. update_key is true for this case. Unused in all
* other cases.
*/
void spum_cipher_req_finish(u8 *spu_hdr,
u16 spu_req_hdr_len,
unsigned int is_inbound,
struct spu_cipher_parms *cipher_parms,
bool update_key,
unsigned int data_size)
{
struct SPUHEADER *spuh;
struct BDESC_HEADER *bdesc;
struct BD_HEADER *bd;
u8 *bdesc_ptr = spu_hdr + spu_req_hdr_len -
(sizeof(struct BD_HEADER) + sizeof(struct BDESC_HEADER));
u32 cipher_bits;
flow_log("%s()\n", __func__);
flow_log(" in: %u\n", is_inbound);
flow_log(" cipher alg: %u, cipher_type: %u\n", cipher_parms->alg,
cipher_parms->type);
if (update_key) {
flow_log(" cipher key len: %u\n", cipher_parms->key_len);
flow_dump(" key: ", cipher_parms->key_buf,
cipher_parms->key_len);
}
/*
* In XTS mode, API puts "i" parameter (block tweak) in IV. For
* SPU-M, should be in start of the BD; tx_sg_create() copies it there.
* IV in SPU msg for SPU-M should be 0, since that's the "j" parameter
* (block ctr within larger data unit) - given we can send entire disk
* block (<= 4KB) in 1 SPU msg, don't need to use this parameter.
*/
if (cipher_parms->mode == CIPHER_MODE_XTS)
memset(cipher_parms->iv_buf, 0, cipher_parms->iv_len);
flow_log(" iv len: %d\n", cipher_parms->iv_len);
flow_dump(" iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
flow_log(" data_size: %u\n", data_size);
/* format master header word */
/* Do not set the next bit even though the datasheet says to */
spuh = (struct SPUHEADER *)spu_hdr;
/* cipher_bits was initialized at setkey time */
cipher_bits = be32_to_cpu(spuh->sa.cipher_flags);
/* Format sctx word 1 (cipher_bits) */
if (is_inbound)
cipher_bits |= CIPHER_INBOUND;
else
cipher_bits &= ~CIPHER_INBOUND;
/* update encryption key for RC4 on non-first chunk */
if (update_key) {
spuh->sa.cipher_flags |=
cipher_parms->type << CIPHER_TYPE_SHIFT;
memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len);
}
if (cipher_parms->alg && cipher_parms->iv_buf && cipher_parms->iv_len)
/* cipher iv provided so put it in here */
memcpy(bdesc_ptr - cipher_parms->iv_len, cipher_parms->iv_buf,
cipher_parms->iv_len);
spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
/* === create the BDESC section === */
bdesc = (struct BDESC_HEADER *)bdesc_ptr;
bdesc->offset_mac = 0;
bdesc->length_mac = 0;
bdesc->offset_crypto = 0;
/* XTS mode, data_size needs to include tweak parameter */
if (cipher_parms->mode == CIPHER_MODE_XTS)
bdesc->length_crypto = cpu_to_be16(data_size +
SPU_XTS_TWEAK_SIZE);
else
bdesc->length_crypto = cpu_to_be16(data_size);
bdesc->offset_icv = 0;
bdesc->offset_iv = 0;
/* === no MFM section === */
/* === create the BD section === */
/* add the BD header */
bd = (struct BD_HEADER *)(bdesc_ptr + sizeof(struct BDESC_HEADER));
bd->size = cpu_to_be16(data_size);
/* XTS mode, data_size needs to include tweak parameter */
if (cipher_parms->mode == CIPHER_MODE_XTS)
bd->size = cpu_to_be16(data_size + SPU_XTS_TWEAK_SIZE);
else
bd->size = cpu_to_be16(data_size);
bd->prev_length = 0;
packet_dump(" SPU request header: ", spu_hdr, spu_req_hdr_len);
}
/**
* spum_request_pad() - Create pad bytes at the end of the data.
* @pad_start: Start of buffer where pad bytes are to be written
* @gcm_ccm_padding: length of GCM/CCM padding, in bytes
* @hash_pad_len: Number of bytes of padding extend data to full block
* @auth_alg: authentication algorithm
* @auth_mode: authentication mode
* @total_sent: length inserted at end of hash pad
* @status_padding: Number of bytes of padding to align STATUS word
*
* There may be three forms of pad:
* 1. GCM/CCM pad - for GCM/CCM mode ciphers, pad to 16-byte alignment
* 2. hash pad - pad to a block length, with 0x80 data terminator and
* size at the end
* 3. STAT pad - to ensure the STAT field is 4-byte aligned
*/
void spum_request_pad(u8 *pad_start,
u32 gcm_ccm_padding,
u32 hash_pad_len,
enum hash_alg auth_alg,
enum hash_mode auth_mode,
unsigned int total_sent, u32 status_padding)
{
u8 *ptr = pad_start;
/* fix data alignent for GCM/CCM */
if (gcm_ccm_padding > 0) {
flow_log(" GCM: padding to 16 byte alignment: %u bytes\n",
gcm_ccm_padding);
memset(ptr, 0, gcm_ccm_padding);
ptr += gcm_ccm_padding;
}
if (hash_pad_len > 0) {
/* clear the padding section */
memset(ptr, 0, hash_pad_len);
if ((auth_alg == HASH_ALG_AES) &&
(auth_mode == HASH_MODE_XCBC)) {
/* AES/XCBC just requires padding to be 0s */
ptr += hash_pad_len;
} else {
/* terminate the data */
*ptr = 0x80;
ptr += (hash_pad_len - sizeof(u64));
/* add the size at the end as required per alg */
if (auth_alg == HASH_ALG_MD5)
*(u64 *)ptr = cpu_to_le64((u64)total_sent * 8);
else /* SHA1, SHA2-224, SHA2-256 */
*(u64 *)ptr = cpu_to_be64((u64)total_sent * 8);
ptr += sizeof(u64);
}
}
/* pad to a 4byte alignment for STAT */
if (status_padding > 0) {
flow_log(" STAT: padding to 4 byte alignment: %u bytes\n",
status_padding);
memset(ptr, 0, status_padding);
ptr += status_padding;
}
}
/**
* spum_xts_tweak_in_payload() - Indicate that SPUM DOES place the XTS tweak
* field in the packet payload (rather than using IV)
*
* Return: 1
*/
u8 spum_xts_tweak_in_payload(void)
{
return 1;
}
/**
* spum_tx_status_len() - Return the length of the STATUS field in a SPU
* response message.
*
* Return: Length of STATUS field in bytes.
*/
u8 spum_tx_status_len(void)
{
return SPU_TX_STATUS_LEN;
}
/**
* spum_rx_status_len() - Return the length of the STATUS field in a SPU
* response message.
*
* Return: Length of STATUS field in bytes.
*/
u8 spum_rx_status_len(void)
{
return SPU_RX_STATUS_LEN;
}
/**
* spum_status_process() - Process the status from a SPU response message.
* @statp: start of STATUS word
* Return:
* 0 - if status is good and response should be processed
* !0 - status indicates an error and response is invalid
*/
int spum_status_process(u8 *statp)
{
u32 status;
status = __be32_to_cpu(*(__be32 *)statp);
flow_log("SPU response STATUS %#08x\n", status);
if (status & SPU_STATUS_ERROR_FLAG) {
pr_err("%s() Warning: Error result from SPU: %#08x\n",
__func__, status);
if (status & SPU_STATUS_INVALID_ICV)
return SPU_INVALID_ICV;
return -EBADMSG;
}
return 0;
}
/**
* spum_ccm_update_iv() - Update the IV as per the requirements for CCM mode.
*
* @digestsize: Digest size of this request
* @cipher_parms: (pointer to) cipher parmaeters, includes IV buf & IV len
* @assoclen: Length of AAD data
* @chunksize: length of input data to be sent in this req
* @is_encrypt: true if this is an output/encrypt operation
* @is_esp: true if this is an ESP / RFC4309 operation
*
*/
void spum_ccm_update_iv(unsigned int digestsize,
struct spu_cipher_parms *cipher_parms,
unsigned int assoclen,
unsigned int chunksize,
bool is_encrypt,
bool is_esp)
{
u8 L; /* L from CCM algorithm, length of plaintext data */
u8 mprime; /* M' from CCM algo, (M - 2) / 2, where M=authsize */
u8 adata;
if (cipher_parms->iv_len != CCM_AES_IV_SIZE) {
pr_err("%s(): Invalid IV len %d for CCM mode, should be %d\n",
__func__, cipher_parms->iv_len, CCM_AES_IV_SIZE);
return;
}
/*
* IV needs to be formatted as follows:
*
* | Byte 0 | Bytes 1 - N | Bytes (N+1) - 15 |
* | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | Bits 7 - 0 | Bits 7 - 0 |
* | 0 |Ad?|(M - 2) / 2| L - 1 | Nonce | Plaintext Length |
*
* Ad? = 1 if AAD present, 0 if not present
* M = size of auth field, 8, 12, or 16 bytes (SPU-M) -or-
* 4, 6, 8, 10, 12, 14, 16 bytes (SPU2)
* L = Size of Plaintext Length field; Nonce size = 15 - L
*
* It appears that the crypto API already expects the L-1 portion
* to be set in the first byte of the IV, which implicitly determines
* the nonce size, and also fills in the nonce. But the other bits
* in byte 0 as well as the plaintext length need to be filled in.
*
* In rfc4309/esp mode, L is not already in the supplied IV and
* we need to fill it in, as well as move the IV data to be after
* the salt
*/
if (is_esp) {
L = CCM_ESP_L_VALUE; /* RFC4309 has fixed L */
} else {
/* L' = plaintext length - 1 so Plaintext length is L' + 1 */
L = ((cipher_parms->iv_buf[0] & CCM_B0_L_PRIME) >>
CCM_B0_L_PRIME_SHIFT) + 1;
}
mprime = (digestsize - 2) >> 1; /* M' = (M - 2) / 2 */
adata = (assoclen > 0); /* adata = 1 if any associated data */
cipher_parms->iv_buf[0] = (adata << CCM_B0_ADATA_SHIFT) |
(mprime << CCM_B0_M_PRIME_SHIFT) |
((L - 1) << CCM_B0_L_PRIME_SHIFT);
/* Nonce is already filled in by crypto API, and is 15 - L bytes */
/* Don't include digest in plaintext size when decrypting */
if (!is_encrypt)
chunksize -= digestsize;
/* Fill in length of plaintext, formatted to be L bytes long */
format_value_ccm(chunksize, &cipher_parms->iv_buf[15 - L + 1], L);
}
/**
* spum_wordalign_padlen() - Given the length of a data field, determine the
* padding required to align the data following this field on a 4-byte boundary.
* @data_size: length of data field in bytes
*
* Return: length of status field padding, in bytes
*/
u32 spum_wordalign_padlen(u32 data_size)
{
return ((data_size + 3) & ~3) - data_size;
}
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