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-rw-r--r--drivers/crypto/bcm/spu.c1214
1 files changed, 1214 insertions, 0 deletions
diff --git a/drivers/crypto/bcm/spu.c b/drivers/crypto/bcm/spu.c
new file mode 100644
index 000000000..6283e8c6d
--- /dev/null
+++ b/drivers/crypto/bcm/spu.c
@@ -0,0 +1,1214 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2016 Broadcom
+ */
+
+#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_cpup((__be32 *)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_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) {
+ struct BDESC_HEADER *bdesc = (struct BDESC_HEADER *)ptr;
+
+ packet_log(" BDESC[0] 0x%08x\n", be32_to_cpup((__be32 *)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_cpup((__be32 *)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_cpup((__be32 *)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) {
+ struct BD_HEADER *bd = (struct BD_HEADER *)ptr;
+
+ packet_log(" BD[0] 0x%08x\n", be32_to_cpup((__be32 *)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;
+}
+
+/**
+ * spum_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_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
+ * @is_inbound: 0 encrypt, 1 decrypt
+ * @cipher_parms: Parameters describing cipher operation to be performed
+ * @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.
+ */
+void spum_cipher_req_finish(u8 *spu_hdr,
+ u16 spu_req_hdr_len,
+ unsigned int is_inbound,
+ struct spu_cipher_parms *cipher_parms,
+ 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);
+
+ /*
+ * 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;
+
+ 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)
+ *(__le64 *)ptr = cpu_to_le64(total_sent * 8ull);
+ else /* SHA1, SHA2-224, SHA2-256 */
+ *(__be64 *)ptr = cpu_to_be64(total_sent * 8ull);
+ 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;
+}