1 /* 2 * Cryptographic API. 3 * 4 * powerpc implementation of the SHA1 Secure Hash Algorithm. 5 * 6 * Derived from cryptoapi implementation, adapted for in-place 7 * scatterlist interface. 8 * 9 * Derived from "crypto/sha1.c" 10 * Copyright (c) Alan Smithee. 11 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk> 12 * Copyright (c) Jean-Francois Dive <jef@linuxbe.org> 13 * 14 * This program is free software; you can redistribute it and/or modify it 15 * under the terms of the GNU General Public License as published by the Free 16 * Software Foundation; either version 2 of the License, or (at your option) 17 * any later version. 18 * 19 */ 20 #include <crypto/internal/hash.h> 21 #include <linux/init.h> 22 #include <linux/module.h> 23 #include <linux/mm.h> 24 #include <linux/cryptohash.h> 25 #include <linux/types.h> 26 #include <crypto/sha.h> 27 #include <asm/byteorder.h> 28 29 extern void powerpc_sha_transform(u32 *state, const u8 *src, u32 *temp); 30 31 static int sha1_init(struct shash_desc *desc) 32 { 33 struct sha1_state *sctx = shash_desc_ctx(desc); 34 35 *sctx = (struct sha1_state){ 36 .state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 }, 37 }; 38 39 return 0; 40 } 41 42 static int sha1_update(struct shash_desc *desc, const u8 *data, 43 unsigned int len) 44 { 45 struct sha1_state *sctx = shash_desc_ctx(desc); 46 unsigned int partial, done; 47 const u8 *src; 48 49 partial = sctx->count & 0x3f; 50 sctx->count += len; 51 done = 0; 52 src = data; 53 54 if ((partial + len) > 63) { 55 u32 temp[SHA_WORKSPACE_WORDS]; 56 57 if (partial) { 58 done = -partial; 59 memcpy(sctx->buffer + partial, data, done + 64); 60 src = sctx->buffer; 61 } 62 63 do { 64 powerpc_sha_transform(sctx->state, src, temp); 65 done += 64; 66 src = data + done; 67 } while (done + 63 < len); 68 69 memzero_explicit(temp, sizeof(temp)); 70 partial = 0; 71 } 72 memcpy(sctx->buffer + partial, src, len - done); 73 74 return 0; 75 } 76 77 78 /* Add padding and return the message digest. */ 79 static int sha1_final(struct shash_desc *desc, u8 *out) 80 { 81 struct sha1_state *sctx = shash_desc_ctx(desc); 82 __be32 *dst = (__be32 *)out; 83 u32 i, index, padlen; 84 __be64 bits; 85 static const u8 padding[64] = { 0x80, }; 86 87 bits = cpu_to_be64(sctx->count << 3); 88 89 /* Pad out to 56 mod 64 */ 90 index = sctx->count & 0x3f; 91 padlen = (index < 56) ? (56 - index) : ((64+56) - index); 92 sha1_update(desc, padding, padlen); 93 94 /* Append length */ 95 sha1_update(desc, (const u8 *)&bits, sizeof(bits)); 96 97 /* Store state in digest */ 98 for (i = 0; i < 5; i++) 99 dst[i] = cpu_to_be32(sctx->state[i]); 100 101 /* Wipe context */ 102 memset(sctx, 0, sizeof *sctx); 103 104 return 0; 105 } 106 107 static int sha1_export(struct shash_desc *desc, void *out) 108 { 109 struct sha1_state *sctx = shash_desc_ctx(desc); 110 111 memcpy(out, sctx, sizeof(*sctx)); 112 return 0; 113 } 114 115 static int sha1_import(struct shash_desc *desc, const void *in) 116 { 117 struct sha1_state *sctx = shash_desc_ctx(desc); 118 119 memcpy(sctx, in, sizeof(*sctx)); 120 return 0; 121 } 122 123 static struct shash_alg alg = { 124 .digestsize = SHA1_DIGEST_SIZE, 125 .init = sha1_init, 126 .update = sha1_update, 127 .final = sha1_final, 128 .export = sha1_export, 129 .import = sha1_import, 130 .descsize = sizeof(struct sha1_state), 131 .statesize = sizeof(struct sha1_state), 132 .base = { 133 .cra_name = "sha1", 134 .cra_driver_name= "sha1-powerpc", 135 .cra_flags = CRYPTO_ALG_TYPE_SHASH, 136 .cra_blocksize = SHA1_BLOCK_SIZE, 137 .cra_module = THIS_MODULE, 138 } 139 }; 140 141 static int __init sha1_powerpc_mod_init(void) 142 { 143 return crypto_register_shash(&alg); 144 } 145 146 static void __exit sha1_powerpc_mod_fini(void) 147 { 148 crypto_unregister_shash(&alg); 149 } 150 151 module_init(sha1_powerpc_mod_init); 152 module_exit(sha1_powerpc_mod_fini); 153 154 MODULE_LICENSE("GPL"); 155 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm"); 156 157 MODULE_ALIAS_CRYPTO("sha1"); 158 MODULE_ALIAS_CRYPTO("sha1-powerpc"); 159