/*
 * 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.
 */

/*
 * This file contains the definition of SPU messages. There are currently two
 * SPU message formats: SPU-M and SPU2. The hardware uses different values to
 * identify the same things in SPU-M vs SPU2. So this file defines values that
 * are hardware independent. Software can use these values for any version of
 * SPU hardware. These values are used in APIs in spu.c. Functions internal to
 * spu.c and spu2.c convert these to hardware-specific values.
 */

#ifndef _SPU_H
#define _SPU_H

#include <linux/types.h>
#include <linux/scatterlist.h>
#include <crypto/sha.h>

enum spu_cipher_alg {
        CIPHER_ALG_NONE = 0x0,
        CIPHER_ALG_RC4 = 0x1,
        CIPHER_ALG_DES = 0x2,
        CIPHER_ALG_3DES = 0x3,
        CIPHER_ALG_AES = 0x4,
        CIPHER_ALG_LAST = 0x5
};

enum spu_cipher_mode {
        CIPHER_MODE_NONE = 0x0,
        CIPHER_MODE_ECB = 0x0,
        CIPHER_MODE_CBC = 0x1,
        CIPHER_MODE_OFB = 0x2,
        CIPHER_MODE_CFB = 0x3,
        CIPHER_MODE_CTR = 0x4,
        CIPHER_MODE_CCM = 0x5,
        CIPHER_MODE_GCM = 0x6,
        CIPHER_MODE_XTS = 0x7,
        CIPHER_MODE_LAST = 0x8
};

enum spu_cipher_type {
        CIPHER_TYPE_NONE = 0x0,
        CIPHER_TYPE_DES = 0x0,
        CIPHER_TYPE_3DES = 0x0,
        CIPHER_TYPE_INIT = 0x0, /* used for ARC4 */
        CIPHER_TYPE_AES128 = 0x0,
        CIPHER_TYPE_AES192 = 0x1,
        CIPHER_TYPE_UPDT = 0x1, /* used for ARC4 */
        CIPHER_TYPE_AES256 = 0x2,
};

enum hash_alg {
        HASH_ALG_NONE = 0x0,
        HASH_ALG_MD5 = 0x1,
        HASH_ALG_SHA1 = 0x2,
        HASH_ALG_SHA224 = 0x3,
        HASH_ALG_SHA256 = 0x4,
        HASH_ALG_AES = 0x5,
        HASH_ALG_SHA384 = 0x6,
        HASH_ALG_SHA512 = 0x7,
        /* Keep SHA3 algorithms at the end always */
        HASH_ALG_SHA3_224 = 0x8,
        HASH_ALG_SHA3_256 = 0x9,
        HASH_ALG_SHA3_384 = 0xa,
        HASH_ALG_SHA3_512 = 0xb,
        HASH_ALG_LAST
};

enum hash_mode {
        HASH_MODE_NONE = 0x0,
        HASH_MODE_HASH = 0x0,
        HASH_MODE_XCBC = 0x0,
        HASH_MODE_CMAC = 0x1,
        HASH_MODE_CTXT = 0x1,
        HASH_MODE_HMAC = 0x2,
        HASH_MODE_RABIN = 0x4,
        HASH_MODE_FHMAC = 0x6,
        HASH_MODE_CCM = 0x5,
        HASH_MODE_GCM = 0x6,
};

enum hash_type {
        HASH_TYPE_NONE = 0x0,
        HASH_TYPE_FULL = 0x0,
        HASH_TYPE_INIT = 0x1,
        HASH_TYPE_UPDT = 0x2,
        HASH_TYPE_FIN = 0x3,
        HASH_TYPE_AES128 = 0x0,
        HASH_TYPE_AES192 = 0x1,
        HASH_TYPE_AES256 = 0x2
};

enum aead_type {
        AES_CCM,
        AES_GCM,
        AUTHENC,
        AEAD_TYPE_LAST
};

extern char *hash_alg_name[HASH_ALG_LAST];
extern char *aead_alg_name[AEAD_TYPE_LAST];

struct spu_request_opts {
        bool is_inbound;
        bool auth_first;
        bool is_aead;
        bool is_esp;
        bool bd_suppress;
        bool is_rfc4543;
};

struct spu_cipher_parms {
        enum spu_cipher_alg  alg;
        enum spu_cipher_mode mode;
        enum spu_cipher_type type;
        u8                  *key_buf;
        u16                  key_len;
        /* iv_buf and iv_len include salt, if applicable */
        u8                  *iv_buf;
        u16                  iv_len;
};

struct spu_hash_parms {
        enum hash_alg  alg;
        enum hash_mode mode;
        enum hash_type type;
        u8             digestsize;
        u8            *key_buf;
        u16            key_len;
        u16            prebuf_len;
        /* length of hash pad. signed, needs to handle roll-overs */
        int            pad_len;
};

struct spu_aead_parms {
        u32 assoc_size;
        u16 iv_len;      /* length of IV field between assoc data and data */
        u8  aad_pad_len; /* For AES GCM/CCM, length of padding after AAD */
        u8  data_pad_len;/* For AES GCM/CCM, length of padding after data */
        bool return_iv;  /* True if SPU should return an IV */
        u32 ret_iv_len;  /* Length in bytes of returned IV */
        u32 ret_iv_off;  /* Offset into full IV if partial IV returned */
};

/************** SPU sizes ***************/

#define SPU_RX_STATUS_LEN  4

/* Max length of padding for 4-byte alignment of STATUS field */
#define SPU_STAT_PAD_MAX  4

/* Max length of pad fragment. 4 is for 4-byte alignment of STATUS field */
#define SPU_PAD_LEN_MAX (SPU_GCM_CCM_ALIGN + MAX_HASH_BLOCK_SIZE + \
                         SPU_STAT_PAD_MAX)

/* GCM and CCM require 16-byte alignment */
#define SPU_GCM_CCM_ALIGN 16

/* Length up SUPDT field in SPU response message for RC4 */
#define SPU_SUPDT_LEN 260

/* SPU status error codes. These used as common error codes across all
 * SPU variants.
 */
#define SPU_INVALID_ICV  1

/* Indicates no limit to the length of the payload in a SPU message */
#define SPU_MAX_PAYLOAD_INF  0xFFFFFFFF

/* Size of XTS tweak ("i" parameter), in bytes */
#define SPU_XTS_TWEAK_SIZE 16

/* CCM B_0 field definitions, common for SPU-M and SPU2 */
#define CCM_B0_ADATA            0x40
#define CCM_B0_ADATA_SHIFT         6
#define CCM_B0_M_PRIME          0x38
#define CCM_B0_M_PRIME_SHIFT       3
#define CCM_B0_L_PRIME          0x07
#define CCM_B0_L_PRIME_SHIFT       0
#define CCM_ESP_L_VALUE            4

/**
 * spu_req_incl_icv() - Return true if SPU request message should include the
 * ICV as a separate buffer.
 * @cipher_mode:  the cipher mode being requested
 * @is_encrypt:   true if encrypting. false if decrypting.
 *
 * Return:  true if ICV to be included as separate buffer
 */
static __always_inline  bool spu_req_incl_icv(enum spu_cipher_mode cipher_mode,
                                              bool is_encrypt)
{
        if ((cipher_mode == CIPHER_MODE_GCM) && !is_encrypt)
                return true;
        if ((cipher_mode == CIPHER_MODE_CCM) && !is_encrypt)
                return true;

        return false;
}

static __always_inline u32 spu_real_db_size(u32 assoc_size,
                                            u32 aead_iv_buf_len,
                                            u32 prebuf_len,
                                            u32 data_size,
                                            u32 aad_pad_len,
                                            u32 gcm_pad_len,
                                            u32 hash_pad_len)
{
        return assoc_size + aead_iv_buf_len + prebuf_len + data_size +
            aad_pad_len + gcm_pad_len + hash_pad_len;
}

/************** SPU Functions Prototypes **************/

void spum_dump_msg_hdr(u8 *buf, unsigned int buf_len);

u32 spum_ns2_ctx_max_payload(enum spu_cipher_alg cipher_alg,
                             enum spu_cipher_mode cipher_mode,
                             unsigned int blocksize);
u32 spum_nsp_ctx_max_payload(enum spu_cipher_alg cipher_alg,
                             enum spu_cipher_mode cipher_mode,
                             unsigned int blocksize);
u32 spum_payload_length(u8 *spu_hdr);
u16 spum_response_hdr_len(u16 auth_key_len, u16 enc_key_len, bool is_hash);
u16 spum_hash_pad_len(enum hash_alg hash_alg, enum hash_mode hash_mode,
                      u32 chunksize, u16 hash_block_size);
u32 spum_gcm_ccm_pad_len(enum spu_cipher_mode cipher_mode,
                         unsigned int data_size);
u32 spum_assoc_resp_len(enum spu_cipher_mode cipher_mode,
                        unsigned int assoc_len, unsigned int iv_len,
                        bool is_encrypt);
u8 spum_aead_ivlen(enum spu_cipher_mode cipher_mode, u16 iv_len);
bool spu_req_incl_icv(enum spu_cipher_mode cipher_mode, bool is_encrypt);
enum hash_type spum_hash_type(u32 src_sent);
u32 spum_digest_size(u32 alg_digest_size, enum hash_alg alg,
                     enum hash_type htype);

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);

u16 spum_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms);

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);

void spum_request_pad(u8 *pad_start,
                      u32 gcm_padding,
                      u32 hash_pad_len,
                      enum hash_alg auth_alg,
                      enum hash_mode auth_mode,
                      unsigned int total_sent, u32 status_padding);

u8 spum_xts_tweak_in_payload(void);
u8 spum_tx_status_len(void);
u8 spum_rx_status_len(void);
int spum_status_process(u8 *statp);

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);
u32 spum_wordalign_padlen(u32 data_size);
#endif