1 /* 2 * Cryptographic API. 3 * 4 * s390 generic implementation of the SHA Secure Hash Algorithms. 5 * 6 * Copyright IBM Corp. 2007 7 * Author(s): Jan Glauber (jang@de.ibm.com) 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the Free 11 * Software Foundation; either version 2 of the License, or (at your option) 12 * any later version. 13 * 14 */ 15 16 #include <crypto/internal/hash.h> 17 #include <linux/module.h> 18 #include <asm/cpacf.h> 19 #include "sha.h" 20 21 int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len) 22 { 23 struct s390_sha_ctx *ctx = shash_desc_ctx(desc); 24 unsigned int bsize = crypto_shash_blocksize(desc->tfm); 25 unsigned int index, n; 26 27 /* how much is already in the buffer? */ 28 index = ctx->count & (bsize - 1); 29 ctx->count += len; 30 31 if ((index + len) < bsize) 32 goto store; 33 34 /* process one stored block */ 35 if (index) { 36 memcpy(ctx->buf + index, data, bsize - index); 37 cpacf_kimd(ctx->func, ctx->state, ctx->buf, bsize); 38 data += bsize - index; 39 len -= bsize - index; 40 index = 0; 41 } 42 43 /* process as many blocks as possible */ 44 if (len >= bsize) { 45 n = len & ~(bsize - 1); 46 cpacf_kimd(ctx->func, ctx->state, data, n); 47 data += n; 48 len -= n; 49 } 50 store: 51 if (len) 52 memcpy(ctx->buf + index , data, len); 53 54 return 0; 55 } 56 EXPORT_SYMBOL_GPL(s390_sha_update); 57 58 int s390_sha_final(struct shash_desc *desc, u8 *out) 59 { 60 struct s390_sha_ctx *ctx = shash_desc_ctx(desc); 61 unsigned int bsize = crypto_shash_blocksize(desc->tfm); 62 u64 bits; 63 unsigned int index, end, plen; 64 65 /* SHA-512 uses 128 bit padding length */ 66 plen = (bsize > SHA256_BLOCK_SIZE) ? 16 : 8; 67 68 /* must perform manual padding */ 69 index = ctx->count & (bsize - 1); 70 end = (index < bsize - plen) ? bsize : (2 * bsize); 71 72 /* start pad with 1 */ 73 ctx->buf[index] = 0x80; 74 index++; 75 76 /* pad with zeros */ 77 memset(ctx->buf + index, 0x00, end - index - 8); 78 79 /* 80 * Append message length. Well, SHA-512 wants a 128 bit length value, 81 * nevertheless we use u64, should be enough for now... 82 */ 83 bits = ctx->count * 8; 84 memcpy(ctx->buf + end - 8, &bits, sizeof(bits)); 85 cpacf_kimd(ctx->func, ctx->state, ctx->buf, end); 86 87 /* copy digest to out */ 88 memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm)); 89 /* wipe context */ 90 memset(ctx, 0, sizeof *ctx); 91 92 return 0; 93 } 94 EXPORT_SYMBOL_GPL(s390_sha_final); 95 96 MODULE_LICENSE("GPL"); 97 MODULE_DESCRIPTION("s390 SHA cipher common functions"); 98