target/linux/generic/patches-3.3/540-crypto-xz-decompression-support.patch

   1 --- a/crypto/Kconfig
   2 +++ b/crypto/Kconfig
   3 @@ -924,6 +924,13 @@ config CRYPTO_LZO
   4         help
   5           This is the LZO algorithm.
   6
   7 +config CRYPTO_XZ
   8 +       tristate "XZ compression algorithm"
   9 +       select CRYPTO_ALGAPI
  10 +       select XZ_DEC
  11 +       help
  12 +         This is the XZ algorithm. Only decompression is supported for now.
  13 +
  14  comment "Random Number Generation"
  15
  16  config CRYPTO_ANSI_CPRNG
  17 --- a/crypto/Makefile
  18 +++ b/crypto/Makefile
  19 @@ -82,6 +82,7 @@ obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += mich
  20  obj-$(CONFIG_CRYPTO_CRC32C) += crc32c.o
  21  obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o authencesn.o
  22  obj-$(CONFIG_CRYPTO_LZO) += lzo.o
  23 +obj-$(CONFIG_CRYPTO_XZ) += xz.o
  24  obj-$(CONFIG_CRYPTO_RNG2) += rng.o
  25  obj-$(CONFIG_CRYPTO_RNG2) += krng.o
  26  obj-$(CONFIG_CRYPTO_ANSI_CPRNG) += ansi_cprng.o
  27 --- /dev/null
  28 +++ b/crypto/xz.c
  29 @@ -0,0 +1,117 @@
  30 +/*
  31 + * Cryptographic API.
  32 + *
  33 + * XZ decompression support.
  34 + *
  35 + * Copyright (c) 2012 Gabor Juhos <juhosg@openwrt.org>
  36 + *
  37 + * This program is free software; you can redistribute it and/or modify it
  38 + * under the terms of the GNU General Public License version 2 as published by
  39 + * the Free Software Foundation.
  40 + *
  41 + */
  42 +#include <linux/init.h>
  43 +#include <linux/module.h>
  44 +#include <linux/crypto.h>
  45 +#include <linux/xz.h>
  46 +#include <linux/interrupt.h>
  47 +#include <linux/mm.h>
  48 +#include <linux/net.h>
  49 +
  50 +struct xz_comp_ctx {
  51 +       struct xz_dec   *decomp_state;
  52 +       struct xz_buf   decomp_buf;
  53 +};
  54 +
  55 +static int crypto_xz_decomp_init(struct xz_comp_ctx *ctx)
  56 +{
  57 +       ctx->decomp_state = xz_dec_init(XZ_SINGLE, 0);
  58 +       if (!ctx->decomp_state)
  59 +               return -ENOMEM;
  60 +
  61 +       return 0;
  62 +}
  63 +
  64 +static void crypto_xz_decomp_exit(struct xz_comp_ctx *ctx)
  65 +{
  66 +       xz_dec_end(ctx->decomp_state);
  67 +}
  68 +
  69 +static int crypto_xz_init(struct crypto_tfm *tfm)
  70 +{
  71 +       struct xz_comp_ctx *ctx = crypto_tfm_ctx(tfm);
  72 +
  73 +       return crypto_xz_decomp_init(ctx);
  74 +}
  75 +
  76 +static void crypto_xz_exit(struct crypto_tfm *tfm)
  77 +{
  78 +       struct xz_comp_ctx *ctx = crypto_tfm_ctx(tfm);
  79 +
  80 +       crypto_xz_decomp_exit(ctx);
  81 +}
  82 +
  83 +static int crypto_xz_compress(struct crypto_tfm *tfm, const u8 *src,
  84 +                             unsigned int slen, u8 *dst, unsigned int *dlen)
  85 +{
  86 +       return -EOPNOTSUPP;
  87 +}
  88 +
  89 +static int crypto_xz_decompress(struct crypto_tfm *tfm, const u8 *src,
  90 +                               unsigned int slen, u8 *dst, unsigned int *dlen)
  91 +{
  92 +       struct xz_comp_ctx *dctx = crypto_tfm_ctx(tfm);
  93 +       struct xz_buf *xz_buf = &dctx->decomp_buf;
  94 +       int ret;
  95 +
  96 +       memset(xz_buf, '\0', sizeof(struct xz_buf));
  97 +
  98 +       xz_buf->in = (u8 *) src;
  99 +       xz_buf->in_pos = 0;
 100 +       xz_buf->in_size = slen;
 101 +       xz_buf->out = (u8 *) dst;
 102 +       xz_buf->out_pos = 0;
 103 +       xz_buf->out_size = *dlen;
 104 +
 105 +       ret = xz_dec_run(dctx->decomp_state, xz_buf);
 106 +       if (ret != XZ_STREAM_END) {
 107 +               ret = -EINVAL;
 108 +               goto out;
 109 +       }
 110 +
 111 +       *dlen = xz_buf->out_pos;
 112 +       ret = 0;
 113 +
 114 +out:
 115 +       return ret;
 116 +}
 117 +
 118 +static struct crypto_alg crypto_xz_alg = {
 119 +       .cra_name               = "xz",
 120 +       .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
 121 +       .cra_ctxsize            = sizeof(struct xz_comp_ctx),
 122 +       .cra_module             = THIS_MODULE,
 123 +       .cra_list               = LIST_HEAD_INIT(crypto_xz_alg.cra_list),
 124 +       .cra_init               = crypto_xz_init,
 125 +       .cra_exit               = crypto_xz_exit,
 126 +       .cra_u                  = { .compress = {
 127 +       .coa_compress           = crypto_xz_compress,
 128 +       .coa_decompress         = crypto_xz_decompress } }
 129 +};
 130 +
 131 +static int __init crypto_xz_mod_init(void)
 132 +{
 133 +       return crypto_register_alg(&crypto_xz_alg);
 134 +}
 135 +
 136 +static void __exit crypto_xz_mod_exit(void)
 137 +{
 138 +       crypto_unregister_alg(&crypto_xz_alg);
 139 +}
 140 +
 141 +module_init(crypto_xz_mod_init);
 142 +module_exit(crypto_xz_mod_exit);
 143 +
 144 +MODULE_LICENSE("GPL v2");
 145 +MODULE_DESCRIPTION("Crypto XZ decompression support");
 146 +MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");