1 /* 2 * sha1-ce-glue.c - SHA-1 secure hash using ARMv8 Crypto Extensions 3 * 4 * Copyright (C) 2014 Linaro Ltd <ard.biesheuvel@linaro.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 #include <asm/neon.h> 12 #include <asm/unaligned.h> 13 #include <crypto/internal/hash.h> 14 #include <crypto/sha.h> 15 #include <linux/cpufeature.h> 16 #include <linux/crypto.h> 17 #include <linux/module.h> 18 19 MODULE_DESCRIPTION("SHA1 secure hash using ARMv8 Crypto Extensions"); 20 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); 21 MODULE_LICENSE("GPL v2"); 22 23 asmlinkage void sha1_ce_transform(int blocks, u8 const *src, u32 *state, 24 u8 *head, long bytes); 25 26 static int sha1_init(struct shash_desc *desc) 27 { 28 struct sha1_state *sctx = shash_desc_ctx(desc); 29 30 *sctx = (struct sha1_state){ 31 .state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 }, 32 }; 33 return 0; 34 } 35 36 static int sha1_update(struct shash_desc *desc, const u8 *data, 37 unsigned int len) 38 { 39 struct sha1_state *sctx = shash_desc_ctx(desc); 40 unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; 41 42 sctx->count += len; 43 44 if ((partial + len) >= SHA1_BLOCK_SIZE) { 45 int blocks; 46 47 if (partial) { 48 int p = SHA1_BLOCK_SIZE - partial; 49 50 memcpy(sctx->buffer + partial, data, p); 51 data += p; 52 len -= p; 53 } 54 55 blocks = len / SHA1_BLOCK_SIZE; 56 len %= SHA1_BLOCK_SIZE; 57 58 kernel_neon_begin_partial(16); 59 sha1_ce_transform(blocks, data, sctx->state, 60 partial ? sctx->buffer : NULL, 0); 61 kernel_neon_end(); 62 63 data += blocks * SHA1_BLOCK_SIZE; 64 partial = 0; 65 } 66 if (len) 67 memcpy(sctx->buffer + partial, data, len); 68 return 0; 69 } 70 71 static int sha1_final(struct shash_desc *desc, u8 *out) 72 { 73 static const u8 padding[SHA1_BLOCK_SIZE] = { 0x80, }; 74 75 struct sha1_state *sctx = shash_desc_ctx(desc); 76 __be64 bits = cpu_to_be64(sctx->count << 3); 77 __be32 *dst = (__be32 *)out; 78 int i; 79 80 u32 padlen = SHA1_BLOCK_SIZE 81 - ((sctx->count + sizeof(bits)) % SHA1_BLOCK_SIZE); 82 83 sha1_update(desc, padding, padlen); 84 sha1_update(desc, (const u8 *)&bits, sizeof(bits)); 85 86 for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++) 87 put_unaligned_be32(sctx->state[i], dst++); 88 89 *sctx = (struct sha1_state){}; 90 return 0; 91 } 92 93 static int sha1_finup(struct shash_desc *desc, const u8 *data, 94 unsigned int len, u8 *out) 95 { 96 struct sha1_state *sctx = shash_desc_ctx(desc); 97 __be32 *dst = (__be32 *)out; 98 int blocks; 99 int i; 100 101 if (sctx->count || !len || (len % SHA1_BLOCK_SIZE)) { 102 sha1_update(desc, data, len); 103 return sha1_final(desc, out); 104 } 105 106 /* 107 * Use a fast path if the input is a multiple of 64 bytes. In 108 * this case, there is no need to copy data around, and we can 109 * perform the entire digest calculation in a single invocation 110 * of sha1_ce_transform() 111 */ 112 blocks = len / SHA1_BLOCK_SIZE; 113 114 kernel_neon_begin_partial(16); 115 sha1_ce_transform(blocks, data, sctx->state, NULL, len); 116 kernel_neon_end(); 117 118 for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++) 119 put_unaligned_be32(sctx->state[i], dst++); 120 121 *sctx = (struct sha1_state){}; 122 return 0; 123 } 124 125 static int sha1_export(struct shash_desc *desc, void *out) 126 { 127 struct sha1_state *sctx = shash_desc_ctx(desc); 128 struct sha1_state *dst = out; 129 130 *dst = *sctx; 131 return 0; 132 } 133 134 static int sha1_import(struct shash_desc *desc, const void *in) 135 { 136 struct sha1_state *sctx = shash_desc_ctx(desc); 137 struct sha1_state const *src = in; 138 139 *sctx = *src; 140 return 0; 141 } 142 143 static struct shash_alg alg = { 144 .init = sha1_init, 145 .update = sha1_update, 146 .final = sha1_final, 147 .finup = sha1_finup, 148 .export = sha1_export, 149 .import = sha1_import, 150 .descsize = sizeof(struct sha1_state), 151 .digestsize = SHA1_DIGEST_SIZE, 152 .statesize = sizeof(struct sha1_state), 153 .base = { 154 .cra_name = "sha1", 155 .cra_driver_name = "sha1-ce", 156 .cra_priority = 200, 157 .cra_flags = CRYPTO_ALG_TYPE_SHASH, 158 .cra_blocksize = SHA1_BLOCK_SIZE, 159 .cra_module = THIS_MODULE, 160 } 161 }; 162 163 static int __init sha1_ce_mod_init(void) 164 { 165 return crypto_register_shash(&alg); 166 } 167 168 static void __exit sha1_ce_mod_fini(void) 169 { 170 crypto_unregister_shash(&alg); 171 } 172 173 module_cpu_feature_match(SHA1, sha1_ce_mod_init); 174 module_exit(sha1_ce_mod_fini); 175