crypto: zlib - New zlib crypto module, using pcomp

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 1676f17..be5d312 100644 (file)
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -748,6 +748,15 @@ config CRYPTO_DEFLATE
 
          You will most probably want this if using IPSec.
 
+config CRYPTO_ZLIB
+       tristate "Zlib compression algorithm"
+       select CRYPTO_PCOMP
+       select ZLIB_INFLATE
+       select ZLIB_DEFLATE
+       select NLATTR
+       help
+         This is the zlib algorithm.
+
 config CRYPTO_LZO
        tristate "LZO compression algorithm"
        select CRYPTO_ALGAPI

diff --git a/crypto/Makefile b/crypto/Makefile
index 1132a67..673d9f7 100644 (file)
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -74,6 +74,7 @@ obj-$(CONFIG_CRYPTO_ANUBIS) += anubis.o
 obj-$(CONFIG_CRYPTO_SEED) += seed.o
 obj-$(CONFIG_CRYPTO_SALSA20) += salsa20_generic.o
 obj-$(CONFIG_CRYPTO_DEFLATE) += deflate.o
+obj-$(CONFIG_CRYPTO_ZLIB) += zlib.o
 obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o
 obj-$(CONFIG_CRYPTO_CRC32C) += crc32c.o
 obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o

diff --git a/crypto/zlib.c b/crypto/zlib.c
new file mode 100644 (file)
index 0000000..33609ba
--- /dev/null
+++ b/crypto/zlib.c
@@ -0,0 +1,378 @@
+/*
+ * Cryptographic API.
+ *
+ * Zlib algorithm
+ *
+ * Copyright 2008 Sony Corporation
+ *
+ * Based on deflate.c, which is
+ * Copyright (c) 2003 James Morris <jmorris@intercode.com.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.
+ *
+ * FIXME: deflate transforms will require up to a total of about 436k of kernel
+ * memory on i386 (390k for compression, the rest for decompression), as the
+ * current zlib kernel code uses a worst case pre-allocation system by default.
+ * This needs to be fixed so that the amount of memory required is properly
+ * related to the winbits and memlevel parameters.
+ */
+
+#define pr_fmt(fmt)    "%s: " fmt, __func__
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/zlib.h>
+#include <linux/vmalloc.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+
+#include <crypto/internal/compress.h>
+
+#include <net/netlink.h>
+
+
+struct zlib_ctx {
+       struct z_stream_s comp_stream;
+       struct z_stream_s decomp_stream;
+       int decomp_windowBits;
+};
+
+
+static void zlib_comp_exit(struct zlib_ctx *ctx)
+{
+       struct z_stream_s *stream = &ctx->comp_stream;
+
+       if (stream->workspace) {
+               zlib_deflateEnd(stream);
+               vfree(stream->workspace);
+               stream->workspace = NULL;
+       }
+}
+
+static void zlib_decomp_exit(struct zlib_ctx *ctx)
+{
+       struct z_stream_s *stream = &ctx->decomp_stream;
+
+       if (stream->workspace) {
+               zlib_inflateEnd(stream);
+               kfree(stream->workspace);
+               stream->workspace = NULL;
+       }
+}
+
+static int zlib_init(struct crypto_tfm *tfm)
+{
+       return 0;
+}
+
+static void zlib_exit(struct crypto_tfm *tfm)
+{
+       struct zlib_ctx *ctx = crypto_tfm_ctx(tfm);
+
+       zlib_comp_exit(ctx);
+       zlib_decomp_exit(ctx);
+}
+
+
+static int zlib_compress_setup(struct crypto_pcomp *tfm, void *params,
+                              unsigned int len)
+{
+       struct zlib_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &ctx->comp_stream;
+       struct nlattr *tb[ZLIB_COMP_MAX + 1];
+       size_t workspacesize;
+       int ret;
+
+       ret = nla_parse(tb, ZLIB_COMP_MAX, params, len, NULL);
+       if (ret)
+               return ret;
+
+       zlib_comp_exit(ctx);
+
+       workspacesize = zlib_deflate_workspacesize();
+       stream->workspace = vmalloc(workspacesize);
+       if (!stream->workspace)
+               return -ENOMEM;
+
+       memset(stream->workspace, 0, workspacesize);
+       ret = zlib_deflateInit2(stream,
+                               tb[ZLIB_COMP_LEVEL]
+                                       ? nla_get_u32(tb[ZLIB_COMP_LEVEL])
+                                       : Z_DEFAULT_COMPRESSION,
+                               tb[ZLIB_COMP_METHOD]
+                                       ? nla_get_u32(tb[ZLIB_COMP_METHOD])
+                                       : Z_DEFLATED,
+                               tb[ZLIB_COMP_WINDOWBITS]
+                                       ? nla_get_u32(tb[ZLIB_COMP_WINDOWBITS])
+                                       : MAX_WBITS,
+                               tb[ZLIB_COMP_MEMLEVEL]
+                                       ? nla_get_u32(tb[ZLIB_COMP_MEMLEVEL])
+                                       : DEF_MEM_LEVEL,
+                               tb[ZLIB_COMP_STRATEGY]
+                                       ? nla_get_u32(tb[ZLIB_COMP_STRATEGY])
+                                       : Z_DEFAULT_STRATEGY);
+       if (ret != Z_OK) {
+               vfree(stream->workspace);
+               stream->workspace = NULL;
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int zlib_compress_init(struct crypto_pcomp *tfm)
+{
+       int ret;
+       struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &dctx->comp_stream;
+
+       ret = zlib_deflateReset(stream);
+       if (ret != Z_OK)
+               return -EINVAL;
+
+       return 0;
+}
+
+static int zlib_compress_update(struct crypto_pcomp *tfm,
+                               struct comp_request *req)
+{
+       int ret;
+       struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &dctx->comp_stream;
+
+       pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
+       stream->next_in = req->next_in;
+       stream->avail_in = req->avail_in;
+       stream->next_out = req->next_out;
+       stream->avail_out = req->avail_out;
+
+       ret = zlib_deflate(stream, Z_NO_FLUSH);
+       switch (ret) {
+       case Z_OK:
+               break;
+
+       case Z_BUF_ERROR:
+               pr_debug("zlib_deflate could not make progress\n");
+               return -EAGAIN;
+
+       default:
+               pr_debug("zlib_deflate failed %d\n", ret);
+               return -EINVAL;
+       }
+
+       pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
+                stream->avail_in, stream->avail_out,
+                req->avail_in - stream->avail_in,
+                req->avail_out - stream->avail_out);
+       req->next_in = stream->next_in;
+       req->avail_in = stream->avail_in;
+       req->next_out = stream->next_out;
+       req->avail_out = stream->avail_out;
+       return 0;
+}
+
+static int zlib_compress_final(struct crypto_pcomp *tfm,
+                              struct comp_request *req)
+{
+       int ret;
+       struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &dctx->comp_stream;
+
+       pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
+       stream->next_in = req->next_in;
+       stream->avail_in = req->avail_in;
+       stream->next_out = req->next_out;
+       stream->avail_out = req->avail_out;
+
+       ret = zlib_deflate(stream, Z_FINISH);
+       if (ret != Z_STREAM_END) {
+               pr_debug("zlib_deflate failed %d\n", ret);
+               return -EINVAL;
+       }
+
+       pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
+                stream->avail_in, stream->avail_out,
+                req->avail_in - stream->avail_in,
+                req->avail_out - stream->avail_out);
+       req->next_in = stream->next_in;
+       req->avail_in = stream->avail_in;
+       req->next_out = stream->next_out;
+       req->avail_out = stream->avail_out;
+       return 0;
+}
+
+
+static int zlib_decompress_setup(struct crypto_pcomp *tfm, void *params,
+                                unsigned int len)
+{
+       struct zlib_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &ctx->decomp_stream;
+       struct nlattr *tb[ZLIB_DECOMP_MAX + 1];
+       int ret = 0;
+
+       ret = nla_parse(tb, ZLIB_DECOMP_MAX, params, len, NULL);
+       if (ret)
+               return ret;
+
+       zlib_decomp_exit(ctx);
+
+       ctx->decomp_windowBits = tb[ZLIB_DECOMP_WINDOWBITS]
+                                ? nla_get_u32(tb[ZLIB_DECOMP_WINDOWBITS])
+                                : DEF_WBITS;
+
+       stream->workspace = kzalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
+       if (!stream->workspace)
+               return -ENOMEM;
+
+       ret = zlib_inflateInit2(stream, ctx->decomp_windowBits);
+       if (ret != Z_OK) {
+               kfree(stream->workspace);
+               stream->workspace = NULL;
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int zlib_decompress_init(struct crypto_pcomp *tfm)
+{
+       int ret;
+       struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &dctx->decomp_stream;
+
+       ret = zlib_inflateReset(stream);
+       if (ret != Z_OK)
+               return -EINVAL;
+
+       return 0;
+}
+
+static int zlib_decompress_update(struct crypto_pcomp *tfm,
+                                 struct comp_request *req)
+{
+       int ret;
+       struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &dctx->decomp_stream;
+
+       pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
+       stream->next_in = req->next_in;
+       stream->avail_in = req->avail_in;
+       stream->next_out = req->next_out;
+       stream->avail_out = req->avail_out;
+
+       ret = zlib_inflate(stream, Z_SYNC_FLUSH);
+       switch (ret) {
+       case Z_OK:
+       case Z_STREAM_END:
+               break;
+
+       case Z_BUF_ERROR:
+               pr_debug("zlib_inflate could not make progress\n");
+               return -EAGAIN;
+
+       default:
+               pr_debug("zlib_inflate failed %d\n", ret);
+               return -EINVAL;
+       }
+
+       pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
+                stream->avail_in, stream->avail_out,
+                req->avail_in - stream->avail_in,
+                req->avail_out - stream->avail_out);
+       req->next_in = stream->next_in;
+       req->avail_in = stream->avail_in;
+       req->next_out = stream->next_out;
+       req->avail_out = stream->avail_out;
+       return 0;
+}
+
+static int zlib_decompress_final(struct crypto_pcomp *tfm,
+                                struct comp_request *req)
+{
+       int ret;
+       struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+       struct z_stream_s *stream = &dctx->decomp_stream;
+
+       pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
+       stream->next_in = req->next_in;
+       stream->avail_in = req->avail_in;
+       stream->next_out = req->next_out;
+       stream->avail_out = req->avail_out;
+
+       if (dctx->decomp_windowBits < 0) {
+               ret = zlib_inflate(stream, Z_SYNC_FLUSH);
+               /*
+                * Work around a bug in zlib, which sometimes wants to taste an
+                * extra byte when being used in the (undocumented) raw deflate
+                * mode. (From USAGI).
+                */
+               if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
+                       const void *saved_next_in = stream->next_in;
+                       u8 zerostuff = 0;
+
+                       stream->next_in = &zerostuff;
+                       stream->avail_in = 1;
+                       ret = zlib_inflate(stream, Z_FINISH);
+                       stream->next_in = saved_next_in;
+                       stream->avail_in = 0;
+               }
+       } else
+               ret = zlib_inflate(stream, Z_FINISH);
+       if (ret != Z_STREAM_END) {
+               pr_debug("zlib_inflate failed %d\n", ret);
+               return -EINVAL;
+       }
+
+       pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
+                stream->avail_in, stream->avail_out,
+                req->avail_in - stream->avail_in,
+                req->avail_out - stream->avail_out);
+       req->next_in = stream->next_in;
+       req->avail_in = stream->avail_in;
+       req->next_out = stream->next_out;
+       req->avail_out = stream->avail_out;
+       return 0;
+}
+
+
+static struct pcomp_alg zlib_alg = {
+       .compress_setup         = zlib_compress_setup,
+       .compress_init          = zlib_compress_init,
+       .compress_update        = zlib_compress_update,
+       .compress_final         = zlib_compress_final,
+       .decompress_setup       = zlib_decompress_setup,
+       .decompress_init        = zlib_decompress_init,
+       .decompress_update      = zlib_decompress_update,
+       .decompress_final       = zlib_decompress_final,
+
+       .base                   = {
+               .cra_name       = "zlib",
+               .cra_flags      = CRYPTO_ALG_TYPE_PCOMPRESS,
+               .cra_ctxsize    = sizeof(struct zlib_ctx),
+               .cra_module     = THIS_MODULE,
+               .cra_init       = zlib_init,
+               .cra_exit       = zlib_exit,
+       }
+};
+
+static int __init zlib_mod_init(void)
+{
+       return crypto_register_pcomp(&zlib_alg);
+}
+
+static void __exit zlib_mod_fini(void)
+{
+       crypto_unregister_pcomp(&zlib_alg);
+}
+
+module_init(zlib_mod_init);
+module_exit(zlib_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Zlib Compression Algorithm");
+MODULE_AUTHOR("Sony Corporation");

diff --git a/include/crypto/compress.h b/include/crypto/compress.h
index b7d2287..86163ef 100644 (file)
--- a/include/crypto/compress.h
+++ b/include/crypto/compress.h
@@ -30,6 +30,26 @@ struct comp_request {
        unsigned int avail_out;         /* bytes available at next_out */
 };
 
+enum zlib_comp_params {
+       ZLIB_COMP_LEVEL = 1,            /* e.g. Z_DEFAULT_COMPRESSION */
+       ZLIB_COMP_METHOD,               /* e.g. Z_DEFLATED */
+       ZLIB_COMP_WINDOWBITS,           /* e.g. MAX_WBITS */
+       ZLIB_COMP_MEMLEVEL,             /* e.g. DEF_MEM_LEVEL */
+       ZLIB_COMP_STRATEGY,             /* e.g. Z_DEFAULT_STRATEGY */
+       __ZLIB_COMP_MAX,
+};
+
+#define ZLIB_COMP_MAX  (__ZLIB_COMP_MAX - 1)
+
+
+enum zlib_decomp_params {
+       ZLIB_DECOMP_WINDOWBITS = 1,     /* e.g. DEF_WBITS */
+       __ZLIB_DECOMP_MAX,
+};
+
+#define ZLIB_DECOMP_MAX        (__ZLIB_DECOMP_MAX - 1)
+
+
 struct crypto_pcomp {
        struct crypto_tfm base;
 };