arch/powerpc/crypto/sha1.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Cryptographic API.
   4  *
   5  * powerpc implementation of the SHA1 Secure Hash Algorithm.
   6  *
   7  * Derived from cryptoapi implementation, adapted for in-place
   8  * scatterlist interface.
   9  *
  10  * Derived from "crypto/sha1.c"
  11  * Copyright (c) Alan Smithee.
  12  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
  13  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
  14  */
  15 #include <crypto/internal/hash.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/mm.h>
  19 #include <linux/types.h>
  20 #include <crypto/sha1.h>
  21 #include <asm/byteorder.h>
  22
  23 void powerpc_sha_transform(u32 *state, const u8 *src);
  24
  25 static int powerpc_sha1_init(struct shash_desc *desc)
  26 {
  27         struct sha1_state *sctx = shash_desc_ctx(desc);
  28
  29         *sctx = (struct sha1_state){
  30                 .state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
  31         };
  32
  33         return 0;
  34 }
  35
  36 static int powerpc_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, done;
  41         const u8 *src;
  42
  43         partial = sctx->count & 0x3f;
  44         sctx->count += len;
  45         done = 0;
  46         src = data;
  47
  48         if ((partial + len) > 63) {
  49
  50                 if (partial) {
  51                         done = -partial;
  52                         memcpy(sctx->buffer + partial, data, done + 64);
  53                         src = sctx->buffer;
  54                 }
  55
  56                 do {
  57                         powerpc_sha_transform(sctx->state, src);
  58                         done += 64;
  59                         src = data + done;
  60                 } while (done + 63 < len);
  61
  62                 partial = 0;
  63         }
  64         memcpy(sctx->buffer + partial, src, len - done);
  65
  66         return 0;
  67 }
  68
  69
  70 /* Add padding and return the message digest. */
  71 static int powerpc_sha1_final(struct shash_desc *desc, u8 *out)
  72 {
  73         struct sha1_state *sctx = shash_desc_ctx(desc);
  74         __be32 *dst = (__be32 *)out;
  75         u32 i, index, padlen;
  76         __be64 bits;
  77         static const u8 padding[64] = { 0x80, };
  78
  79         bits = cpu_to_be64(sctx->count << 3);
  80
  81         /* Pad out to 56 mod 64 */
  82         index = sctx->count & 0x3f;
  83         padlen = (index < 56) ? (56 - index) : ((64+56) - index);
  84         powerpc_sha1_update(desc, padding, padlen);
  85
  86         /* Append length */
  87         powerpc_sha1_update(desc, (const u8 *)&bits, sizeof(bits));
  88
  89         /* Store state in digest */
  90         for (i = 0; i < 5; i++)
  91                 dst[i] = cpu_to_be32(sctx->state[i]);
  92
  93         /* Wipe context */
  94         memset(sctx, 0, sizeof *sctx);
  95
  96         return 0;
  97 }
  98
  99 static int powerpc_sha1_export(struct shash_desc *desc, void *out)
 100 {
 101         struct sha1_state *sctx = shash_desc_ctx(desc);
 102
 103         memcpy(out, sctx, sizeof(*sctx));
 104         return 0;
 105 }
 106
 107 static int powerpc_sha1_import(struct shash_desc *desc, const void *in)
 108 {
 109         struct sha1_state *sctx = shash_desc_ctx(desc);
 110
 111         memcpy(sctx, in, sizeof(*sctx));
 112         return 0;
 113 }
 114
 115 static struct shash_alg alg = {
 116         .digestsize     =       SHA1_DIGEST_SIZE,
 117         .init           =       powerpc_sha1_init,
 118         .update         =       powerpc_sha1_update,
 119         .final          =       powerpc_sha1_final,
 120         .export         =       powerpc_sha1_export,
 121         .import         =       powerpc_sha1_import,
 122         .descsize       =       sizeof(struct sha1_state),
 123         .statesize      =       sizeof(struct sha1_state),
 124         .base           =       {
 125                 .cra_name       =       "sha1",
 126                 .cra_driver_name=       "sha1-powerpc",
 127                 .cra_blocksize  =       SHA1_BLOCK_SIZE,
 128                 .cra_module     =       THIS_MODULE,
 129         }
 130 };
 131
 132 static int __init sha1_powerpc_mod_init(void)
 133 {
 134         return crypto_register_shash(&alg);
 135 }
 136
 137 static void __exit sha1_powerpc_mod_fini(void)
 138 {
 139         crypto_unregister_shash(&alg);
 140 }
 141
 142 module_init(sha1_powerpc_mod_init);
 143 module_exit(sha1_powerpc_mod_fini);
 144
 145 MODULE_LICENSE("GPL");
 146 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
 147
 148 MODULE_ALIAS_CRYPTO("sha1");
 149 MODULE_ALIAS_CRYPTO("sha1-powerpc");