db83aabfe1
Signed-off-by: Richard Hartmann <richih.mailinglist@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
261 lines
8.0 KiB
C
261 lines
8.0 KiB
C
/*
|
|
* Cryptographic API.
|
|
*
|
|
* CRC32C chksum
|
|
*
|
|
*@Article{castagnoli-crc,
|
|
* author = { Guy Castagnoli and Stefan Braeuer and Martin Herrman},
|
|
* title = {{Optimization of Cyclic Redundancy-Check Codes with 24
|
|
* and 32 Parity Bits}},
|
|
* journal = IEEE Transactions on Communication,
|
|
* year = {1993},
|
|
* volume = {41},
|
|
* number = {6},
|
|
* pages = {},
|
|
* month = {June},
|
|
*}
|
|
* Used by the iSCSI driver, possibly others, and derived from the
|
|
* the iscsi-crc.c module of the linux-iscsi driver at
|
|
* http://linux-iscsi.sourceforge.net.
|
|
*
|
|
* Following the example of lib/crc32, this function is intended to be
|
|
* flexible and useful for all users. Modules that currently have their
|
|
* own crc32c, but hopefully may be able to use this one are:
|
|
* net/sctp (please add all your doco to here if you change to
|
|
* use this one!)
|
|
* <endoflist>
|
|
*
|
|
* Copyright (c) 2004 Cisco Systems, Inc.
|
|
* Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
|
|
*
|
|
* 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 <crypto/internal/hash.h>
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/string.h>
|
|
#include <linux/kernel.h>
|
|
|
|
#define CHKSUM_BLOCK_SIZE 1
|
|
#define CHKSUM_DIGEST_SIZE 4
|
|
|
|
struct chksum_ctx {
|
|
u32 key;
|
|
};
|
|
|
|
struct chksum_desc_ctx {
|
|
u32 crc;
|
|
};
|
|
|
|
/*
|
|
* This is the CRC-32C table
|
|
* Generated with:
|
|
* width = 32 bits
|
|
* poly = 0x1EDC6F41
|
|
* reflect input bytes = true
|
|
* reflect output bytes = true
|
|
*/
|
|
|
|
static const u32 crc32c_table[256] = {
|
|
0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L,
|
|
0xC79A971FL, 0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL,
|
|
0x8AD958CFL, 0x78B2DBCCL, 0x6BE22838L, 0x9989AB3BL,
|
|
0x4D43CFD0L, 0xBF284CD3L, 0xAC78BF27L, 0x5E133C24L,
|
|
0x105EC76FL, 0xE235446CL, 0xF165B798L, 0x030E349BL,
|
|
0xD7C45070L, 0x25AFD373L, 0x36FF2087L, 0xC494A384L,
|
|
0x9A879FA0L, 0x68EC1CA3L, 0x7BBCEF57L, 0x89D76C54L,
|
|
0x5D1D08BFL, 0xAF768BBCL, 0xBC267848L, 0x4E4DFB4BL,
|
|
0x20BD8EDEL, 0xD2D60DDDL, 0xC186FE29L, 0x33ED7D2AL,
|
|
0xE72719C1L, 0x154C9AC2L, 0x061C6936L, 0xF477EA35L,
|
|
0xAA64D611L, 0x580F5512L, 0x4B5FA6E6L, 0xB93425E5L,
|
|
0x6DFE410EL, 0x9F95C20DL, 0x8CC531F9L, 0x7EAEB2FAL,
|
|
0x30E349B1L, 0xC288CAB2L, 0xD1D83946L, 0x23B3BA45L,
|
|
0xF779DEAEL, 0x05125DADL, 0x1642AE59L, 0xE4292D5AL,
|
|
0xBA3A117EL, 0x4851927DL, 0x5B016189L, 0xA96AE28AL,
|
|
0x7DA08661L, 0x8FCB0562L, 0x9C9BF696L, 0x6EF07595L,
|
|
0x417B1DBCL, 0xB3109EBFL, 0xA0406D4BL, 0x522BEE48L,
|
|
0x86E18AA3L, 0x748A09A0L, 0x67DAFA54L, 0x95B17957L,
|
|
0xCBA24573L, 0x39C9C670L, 0x2A993584L, 0xD8F2B687L,
|
|
0x0C38D26CL, 0xFE53516FL, 0xED03A29BL, 0x1F682198L,
|
|
0x5125DAD3L, 0xA34E59D0L, 0xB01EAA24L, 0x42752927L,
|
|
0x96BF4DCCL, 0x64D4CECFL, 0x77843D3BL, 0x85EFBE38L,
|
|
0xDBFC821CL, 0x2997011FL, 0x3AC7F2EBL, 0xC8AC71E8L,
|
|
0x1C661503L, 0xEE0D9600L, 0xFD5D65F4L, 0x0F36E6F7L,
|
|
0x61C69362L, 0x93AD1061L, 0x80FDE395L, 0x72966096L,
|
|
0xA65C047DL, 0x5437877EL, 0x4767748AL, 0xB50CF789L,
|
|
0xEB1FCBADL, 0x197448AEL, 0x0A24BB5AL, 0xF84F3859L,
|
|
0x2C855CB2L, 0xDEEEDFB1L, 0xCDBE2C45L, 0x3FD5AF46L,
|
|
0x7198540DL, 0x83F3D70EL, 0x90A324FAL, 0x62C8A7F9L,
|
|
0xB602C312L, 0x44694011L, 0x5739B3E5L, 0xA55230E6L,
|
|
0xFB410CC2L, 0x092A8FC1L, 0x1A7A7C35L, 0xE811FF36L,
|
|
0x3CDB9BDDL, 0xCEB018DEL, 0xDDE0EB2AL, 0x2F8B6829L,
|
|
0x82F63B78L, 0x709DB87BL, 0x63CD4B8FL, 0x91A6C88CL,
|
|
0x456CAC67L, 0xB7072F64L, 0xA457DC90L, 0x563C5F93L,
|
|
0x082F63B7L, 0xFA44E0B4L, 0xE9141340L, 0x1B7F9043L,
|
|
0xCFB5F4A8L, 0x3DDE77ABL, 0x2E8E845FL, 0xDCE5075CL,
|
|
0x92A8FC17L, 0x60C37F14L, 0x73938CE0L, 0x81F80FE3L,
|
|
0x55326B08L, 0xA759E80BL, 0xB4091BFFL, 0x466298FCL,
|
|
0x1871A4D8L, 0xEA1A27DBL, 0xF94AD42FL, 0x0B21572CL,
|
|
0xDFEB33C7L, 0x2D80B0C4L, 0x3ED04330L, 0xCCBBC033L,
|
|
0xA24BB5A6L, 0x502036A5L, 0x4370C551L, 0xB11B4652L,
|
|
0x65D122B9L, 0x97BAA1BAL, 0x84EA524EL, 0x7681D14DL,
|
|
0x2892ED69L, 0xDAF96E6AL, 0xC9A99D9EL, 0x3BC21E9DL,
|
|
0xEF087A76L, 0x1D63F975L, 0x0E330A81L, 0xFC588982L,
|
|
0xB21572C9L, 0x407EF1CAL, 0x532E023EL, 0xA145813DL,
|
|
0x758FE5D6L, 0x87E466D5L, 0x94B49521L, 0x66DF1622L,
|
|
0x38CC2A06L, 0xCAA7A905L, 0xD9F75AF1L, 0x2B9CD9F2L,
|
|
0xFF56BD19L, 0x0D3D3E1AL, 0x1E6DCDEEL, 0xEC064EEDL,
|
|
0xC38D26C4L, 0x31E6A5C7L, 0x22B65633L, 0xD0DDD530L,
|
|
0x0417B1DBL, 0xF67C32D8L, 0xE52CC12CL, 0x1747422FL,
|
|
0x49547E0BL, 0xBB3FFD08L, 0xA86F0EFCL, 0x5A048DFFL,
|
|
0x8ECEE914L, 0x7CA56A17L, 0x6FF599E3L, 0x9D9E1AE0L,
|
|
0xD3D3E1ABL, 0x21B862A8L, 0x32E8915CL, 0xC083125FL,
|
|
0x144976B4L, 0xE622F5B7L, 0xF5720643L, 0x07198540L,
|
|
0x590AB964L, 0xAB613A67L, 0xB831C993L, 0x4A5A4A90L,
|
|
0x9E902E7BL, 0x6CFBAD78L, 0x7FAB5E8CL, 0x8DC0DD8FL,
|
|
0xE330A81AL, 0x115B2B19L, 0x020BD8EDL, 0xF0605BEEL,
|
|
0x24AA3F05L, 0xD6C1BC06L, 0xC5914FF2L, 0x37FACCF1L,
|
|
0x69E9F0D5L, 0x9B8273D6L, 0x88D28022L, 0x7AB90321L,
|
|
0xAE7367CAL, 0x5C18E4C9L, 0x4F48173DL, 0xBD23943EL,
|
|
0xF36E6F75L, 0x0105EC76L, 0x12551F82L, 0xE03E9C81L,
|
|
0x34F4F86AL, 0xC69F7B69L, 0xD5CF889DL, 0x27A40B9EL,
|
|
0x79B737BAL, 0x8BDCB4B9L, 0x988C474DL, 0x6AE7C44EL,
|
|
0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L, 0xAD7D5351L
|
|
};
|
|
|
|
/*
|
|
* Steps through buffer one byte at at time, calculates reflected
|
|
* crc using table.
|
|
*/
|
|
|
|
static u32 crc32c(u32 crc, const u8 *data, unsigned int length)
|
|
{
|
|
while (length--)
|
|
crc = crc32c_table[(crc ^ *data++) & 0xFFL] ^ (crc >> 8);
|
|
|
|
return crc;
|
|
}
|
|
|
|
/*
|
|
* Steps through buffer one byte at at time, calculates reflected
|
|
* crc using table.
|
|
*/
|
|
|
|
static int chksum_init(struct shash_desc *desc)
|
|
{
|
|
struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
|
|
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
|
|
|
|
ctx->crc = mctx->key;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Setting the seed allows arbitrary accumulators and flexible XOR policy
|
|
* If your algorithm starts with ~0, then XOR with ~0 before you set
|
|
* the seed.
|
|
*/
|
|
static int chksum_setkey(struct crypto_shash *tfm, const u8 *key,
|
|
unsigned int keylen)
|
|
{
|
|
struct chksum_ctx *mctx = crypto_shash_ctx(tfm);
|
|
|
|
if (keylen != sizeof(mctx->key)) {
|
|
crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
|
|
return -EINVAL;
|
|
}
|
|
mctx->key = le32_to_cpu(*(__le32 *)key);
|
|
return 0;
|
|
}
|
|
|
|
static int chksum_update(struct shash_desc *desc, const u8 *data,
|
|
unsigned int length)
|
|
{
|
|
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
|
|
|
|
ctx->crc = crc32c(ctx->crc, data, length);
|
|
return 0;
|
|
}
|
|
|
|
static int chksum_final(struct shash_desc *desc, u8 *out)
|
|
{
|
|
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
|
|
|
|
*(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
|
|
return 0;
|
|
}
|
|
|
|
static int __chksum_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out)
|
|
{
|
|
*(__le32 *)out = ~cpu_to_le32(crc32c(*crcp, data, len));
|
|
return 0;
|
|
}
|
|
|
|
static int chksum_finup(struct shash_desc *desc, const u8 *data,
|
|
unsigned int len, u8 *out)
|
|
{
|
|
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
|
|
|
|
return __chksum_finup(&ctx->crc, data, len, out);
|
|
}
|
|
|
|
static int chksum_digest(struct shash_desc *desc, const u8 *data,
|
|
unsigned int length, u8 *out)
|
|
{
|
|
struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
|
|
|
|
return __chksum_finup(&mctx->key, data, length, out);
|
|
}
|
|
|
|
static int crc32c_cra_init(struct crypto_tfm *tfm)
|
|
{
|
|
struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
|
|
|
|
mctx->key = ~0;
|
|
return 0;
|
|
}
|
|
|
|
static struct shash_alg alg = {
|
|
.digestsize = CHKSUM_DIGEST_SIZE,
|
|
.setkey = chksum_setkey,
|
|
.init = chksum_init,
|
|
.update = chksum_update,
|
|
.final = chksum_final,
|
|
.finup = chksum_finup,
|
|
.digest = chksum_digest,
|
|
.descsize = sizeof(struct chksum_desc_ctx),
|
|
.base = {
|
|
.cra_name = "crc32c",
|
|
.cra_driver_name = "crc32c-generic",
|
|
.cra_priority = 100,
|
|
.cra_blocksize = CHKSUM_BLOCK_SIZE,
|
|
.cra_alignmask = 3,
|
|
.cra_ctxsize = sizeof(struct chksum_ctx),
|
|
.cra_module = THIS_MODULE,
|
|
.cra_init = crc32c_cra_init,
|
|
}
|
|
};
|
|
|
|
static int __init crc32c_mod_init(void)
|
|
{
|
|
return crypto_register_shash(&alg);
|
|
}
|
|
|
|
static void __exit crc32c_mod_fini(void)
|
|
{
|
|
crypto_unregister_shash(&alg);
|
|
}
|
|
|
|
module_init(crc32c_mod_init);
|
|
module_exit(crc32c_mod_fini);
|
|
|
|
MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
|
|
MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations wrapper for lib/crc32c");
|
|
MODULE_LICENSE("GPL");
|