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Diffstat (limited to 'crypto/842.c')
| -rw-r--r-- | crypto/842.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/crypto/842.c b/crypto/842.c new file mode 100644 index 000000000..bc26dc942 --- /dev/null +++ b/crypto/842.c @@ -0,0 +1,160 @@ +/* + * Cryptographic API for the 842 software compression algorithm. + * + * 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. + * + * 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 for more details. + * + * Copyright (C) IBM Corporation, 2011-2015 + * + * Original Authors: Robert Jennings <rcj@linux.vnet.ibm.com> + * Seth Jennings <sjenning@linux.vnet.ibm.com> + * + * Rewrite: Dan Streetman <ddstreet@ieee.org> + * + * This is the software implementation of compression and decompression using + * the 842 format. This uses the software 842 library at lib/842/ which is + * only a reference implementation, and is very, very slow as compared to other + * software compressors. You probably do not want to use this software + * compression. If you have access to the PowerPC 842 compression hardware, you + * want to use the 842 hardware compression interface, which is at: + * drivers/crypto/nx/nx-842-crypto.c + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/crypto.h> +#include <linux/sw842.h> +#include <crypto/internal/scompress.h> + +struct crypto842_ctx { + void *wmem; /* working memory for compress */ +}; + +static void *crypto842_alloc_ctx(struct crypto_scomp *tfm) +{ + void *ctx; + + ctx = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL); + if (!ctx) + return ERR_PTR(-ENOMEM); + + return ctx; +} + +static int crypto842_init(struct crypto_tfm *tfm) +{ + struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm); + + ctx->wmem = crypto842_alloc_ctx(NULL); + if (IS_ERR(ctx->wmem)) + return -ENOMEM; + + return 0; +} + +static void crypto842_free_ctx(struct crypto_scomp *tfm, void *ctx) +{ + kfree(ctx); +} + +static void crypto842_exit(struct crypto_tfm *tfm) +{ + struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto842_free_ctx(NULL, ctx->wmem); +} + +static int crypto842_compress(struct crypto_tfm *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int *dlen) +{ + struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm); + + return sw842_compress(src, slen, dst, dlen, ctx->wmem); +} + +static int crypto842_scompress(struct crypto_scomp *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int *dlen, void *ctx) +{ + return sw842_compress(src, slen, dst, dlen, ctx); +} + +static int crypto842_decompress(struct crypto_tfm *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int *dlen) +{ + return sw842_decompress(src, slen, dst, dlen); +} + +static int crypto842_sdecompress(struct crypto_scomp *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int *dlen, void *ctx) +{ + return sw842_decompress(src, slen, dst, dlen); +} + +static struct crypto_alg alg = { + .cra_name = "842", + .cra_driver_name = "842-generic", + .cra_priority = 100, + .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, + .cra_ctxsize = sizeof(struct crypto842_ctx), + .cra_module = THIS_MODULE, + .cra_init = crypto842_init, + .cra_exit = crypto842_exit, + .cra_u = { .compress = { + .coa_compress = crypto842_compress, + .coa_decompress = crypto842_decompress } } +}; + +static struct scomp_alg scomp = { + .alloc_ctx = crypto842_alloc_ctx, + .free_ctx = crypto842_free_ctx, + .compress = crypto842_scompress, + .decompress = crypto842_sdecompress, + .base = { + .cra_name = "842", + .cra_driver_name = "842-scomp", + .cra_priority = 100, + .cra_module = THIS_MODULE, + } +}; + +static int __init crypto842_mod_init(void) +{ + int ret; + + ret = crypto_register_alg(&alg); + if (ret) + return ret; + + ret = crypto_register_scomp(&scomp); + if (ret) { + crypto_unregister_alg(&alg); + return ret; + } + + return ret; +} +module_init(crypto842_mod_init); + +static void __exit crypto842_mod_exit(void) +{ + crypto_unregister_alg(&alg); + crypto_unregister_scomp(&scomp); +} +module_exit(crypto842_mod_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("842 Software Compression Algorithm"); +MODULE_ALIAS_CRYPTO("842"); +MODULE_ALIAS_CRYPTO("842-generic"); +MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>"); |