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 "sha.h" 19 #include "crypt_s390.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; 26 int ret; 27 28 /* how much is already in the buffer? */ 29 index = ctx->count & (bsize - 1); 30 ctx->count += len; 31 32 if ((index + len) < bsize) 33 goto store; 34 35 /* process one stored block */ 36 if (index) { 37 memcpy(ctx->buf + index, data, bsize - index); 38 ret = crypt_s390_kimd(ctx->func, ctx->state, ctx->buf, bsize); 39 if (ret != bsize) 40 return -EIO; 41 data += bsize - index; 42 len -= bsize - index; 43 index = 0; 44 } 45 46 /* process as many blocks as possible */ 47 if (len >= bsize) { 48 ret = crypt_s390_kimd(ctx->func, ctx->state, data, 49 len & ~(bsize - 1)); 50 if (ret != (len & ~(bsize - 1))) 51 return -EIO; 52 data += ret; 53 len -= ret; 54 } 55 store: 56 if (len) 57 memcpy(ctx->buf + index , data, len); 58 59 return 0; 60 } 61 EXPORT_SYMBOL_GPL(s390_sha_update); 62 63 int s390_sha_final(struct shash_desc *desc, u8 *out) 64 { 65 struct s390_sha_ctx *ctx = shash_desc_ctx(desc); 66 unsigned int bsize = crypto_shash_blocksize(desc->tfm); 67 u64 bits; 68 unsigned int index, end, plen; 69 int ret; 70 71 /* SHA-512 uses 128 bit padding length */ 72 plen = (bsize > SHA256_BLOCK_SIZE) ? 16 : 8; 73 74 /* must perform manual padding */ 75 index = ctx->count & (bsize - 1); 76 end = (index < bsize - plen) ? bsize : (2 * bsize); 77 78 /* start pad with 1 */ 79 ctx->buf[index] = 0x80; 80 index++; 81 82 /* pad with zeros */ 83 memset(ctx->buf + index, 0x00, end - index - 8); 84 85 /* 86 * Append message length. Well, SHA-512 wants a 128 bit length value, 87 * nevertheless we use u64, should be enough for now... 88 */ 89 bits = ctx->count * 8; 90 memcpy(ctx->buf + end - 8, &bits, sizeof(bits)); 91 92 ret = crypt_s390_kimd(ctx->func, ctx->state, ctx->buf, end); 93 if (ret != end) 94 return -EIO; 95 96 /* copy digest to out */ 97 memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm)); 98 /* wipe context */ 99 memset(ctx, 0, sizeof *ctx); 100 101 return 0; 102 } 103 EXPORT_SYMBOL_GPL(s390_sha_final); 104 105 MODULE_LICENSE("GPL"); 106 MODULE_DESCRIPTION("s390 SHA cipher common functions"); 107