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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 | /* * Cryptographic API for the 842 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * Copyright (C) IBM Corporation, 2011 * * Authors: Robert Jennings <rcj@linux.vnet.ibm.com> * Seth Jennings <sjenning@linux.vnet.ibm.com> */ #include <linux/init.h> #include <linux/module.h> #include <linux/crypto.h> #include <linux/vmalloc.h> #include <linux/nx842.h> #include <linux/lzo.h> #include <linux/timer.h> static int nx842_uselzo; struct nx842_ctx { void *nx842_wmem; /* working memory for 842/lzo */ }; enum nx842_crypto_type { NX842_CRYPTO_TYPE_842, NX842_CRYPTO_TYPE_LZO }; #define NX842_SENTINEL 0xdeadbeef struct nx842_crypto_header { unsigned int sentinel; /* debug */ enum nx842_crypto_type type; }; static int nx842_init(struct crypto_tfm *tfm) { struct nx842_ctx *ctx = crypto_tfm_ctx(tfm); int wmemsize; wmemsize = max_t(int, nx842_get_workmem_size(), LZO1X_MEM_COMPRESS); ctx->nx842_wmem = kmalloc(wmemsize, GFP_NOFS); if (!ctx->nx842_wmem) return -ENOMEM; return 0; } static void nx842_exit(struct crypto_tfm *tfm) { struct nx842_ctx *ctx = crypto_tfm_ctx(tfm); kfree(ctx->nx842_wmem); } static void nx842_reset_uselzo(unsigned long data) { nx842_uselzo = 0; } static DEFINE_TIMER(failover_timer, nx842_reset_uselzo, 0, 0); static int nx842_crypto_compress(struct crypto_tfm *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen) { struct nx842_ctx *ctx = crypto_tfm_ctx(tfm); struct nx842_crypto_header *hdr; unsigned int tmp_len = *dlen; size_t lzodlen; /* needed for lzo */ int err; *dlen = 0; hdr = (struct nx842_crypto_header *)dst; hdr->sentinel = NX842_SENTINEL; /* debug */ dst += sizeof(struct nx842_crypto_header); tmp_len -= sizeof(struct nx842_crypto_header); lzodlen = tmp_len; if (likely(!nx842_uselzo)) { err = nx842_compress(src, slen, dst, &tmp_len, ctx->nx842_wmem); if (likely(!err)) { hdr->type = NX842_CRYPTO_TYPE_842; *dlen = tmp_len + sizeof(struct nx842_crypto_header); return 0; } /* hardware failed */ nx842_uselzo = 1; /* set timer to check for hardware again in 1 second */ mod_timer(&failover_timer, jiffies + msecs_to_jiffies(1000)); } /* no hardware, use lzo */ err = lzo1x_1_compress(src, slen, dst, &lzodlen, ctx->nx842_wmem); if (err != LZO_E_OK) return -EINVAL; hdr->type = NX842_CRYPTO_TYPE_LZO; *dlen = lzodlen + sizeof(struct nx842_crypto_header); return 0; } static int nx842_crypto_decompress(struct crypto_tfm *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen) { struct nx842_ctx *ctx = crypto_tfm_ctx(tfm); struct nx842_crypto_header *hdr; unsigned int tmp_len = *dlen; size_t lzodlen; /* needed for lzo */ int err; *dlen = 0; hdr = (struct nx842_crypto_header *)src; if (unlikely(hdr->sentinel != NX842_SENTINEL)) return -EINVAL; src += sizeof(struct nx842_crypto_header); slen -= sizeof(struct nx842_crypto_header); if (likely(hdr->type == NX842_CRYPTO_TYPE_842)) { err = nx842_decompress(src, slen, dst, &tmp_len, ctx->nx842_wmem); if (err) return -EINVAL; *dlen = tmp_len; } else if (hdr->type == NX842_CRYPTO_TYPE_LZO) { lzodlen = tmp_len; err = lzo1x_decompress_safe(src, slen, dst, &lzodlen); if (err != LZO_E_OK) return -EINVAL; *dlen = lzodlen; } else return -EINVAL; return 0; } static struct crypto_alg alg = { .cra_name = "842", .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, .cra_ctxsize = sizeof(struct nx842_ctx), .cra_module = THIS_MODULE, .cra_init = nx842_init, .cra_exit = nx842_exit, .cra_u = { .compress = { .coa_compress = nx842_crypto_compress, .coa_decompress = nx842_crypto_decompress } } }; static int __init nx842_mod_init(void) { del_timer(&failover_timer); return crypto_register_alg(&alg); } static void __exit nx842_mod_exit(void) { crypto_unregister_alg(&alg); } module_init(nx842_mod_init); module_exit(nx842_mod_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("842 Compression Algorithm"); |