zfs/module/icp/algs/modes/ecb.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #include <sys/zfs_context.h>
  27 #include <modes/modes.h>
  28 #include <sys/crypto/common.h>
  29 #include <sys/crypto/impl.h>
  30
  31 /*
  32  * Algorithm independent ECB functions.
  33  */
  34 int
  35 ecb_cipher_contiguous_blocks(ecb_ctx_t *ctx, char *data, size_t length,
  36     crypto_data_t *out, size_t block_size,
  37     int (*cipher)(const void *ks, const uint8_t *pt, uint8_t *ct))
  38 {
  39         size_t remainder = length;
  40         size_t need = 0;
  41         uint8_t *datap = (uint8_t *)data;
  42         uint8_t *blockp;
  43         uint8_t *lastp;
  44         void *iov_or_mp;
  45         offset_t offset;
  46         uint8_t *out_data_1;
  47         uint8_t *out_data_2;
  48         size_t out_data_1_len;
  49
  50         if (length + ctx->ecb_remainder_len < block_size) {
  51                 /* accumulate bytes here and return */
  52                 bcopy(datap,
  53                     (uint8_t *)ctx->ecb_remainder + ctx->ecb_remainder_len,
  54                     length);
  55                 ctx->ecb_remainder_len += length;
  56                 ctx->ecb_copy_to = datap;
  57                 return (CRYPTO_SUCCESS);
  58         }
  59
  60         lastp = (uint8_t *)ctx->ecb_iv;
  61         if (out != NULL)
  62                 crypto_init_ptrs(out, &iov_or_mp, &offset);
  63
  64         do {
  65                 /* Unprocessed data from last call. */
  66                 if (ctx->ecb_remainder_len > 0) {
  67                         need = block_size - ctx->ecb_remainder_len;
  68
  69                         if (need > remainder)
  70                                 return (CRYPTO_DATA_LEN_RANGE);
  71
  72                         bcopy(datap, &((uint8_t *)ctx->ecb_remainder)
  73                             [ctx->ecb_remainder_len], need);
  74
  75                         blockp = (uint8_t *)ctx->ecb_remainder;
  76                 } else {
  77                         blockp = datap;
  78                 }
  79
  80                 if (out == NULL) {
  81                         cipher(ctx->ecb_keysched, blockp, blockp);
  82
  83                         ctx->ecb_lastp = blockp;
  84                         lastp = blockp;
  85
  86                         if (ctx->ecb_remainder_len > 0) {
  87                                 bcopy(blockp, ctx->ecb_copy_to,
  88                                     ctx->ecb_remainder_len);
  89                                 bcopy(blockp + ctx->ecb_remainder_len, datap,
  90                                     need);
  91                         }
  92                 } else {
  93                         cipher(ctx->ecb_keysched, blockp, lastp);
  94                         crypto_get_ptrs(out, &iov_or_mp, &offset, &out_data_1,
  95                             &out_data_1_len, &out_data_2, block_size);
  96
  97                         /* copy block to where it belongs */
  98                         bcopy(lastp, out_data_1, out_data_1_len);
  99                         if (out_data_2 != NULL) {
 100                                 bcopy(lastp + out_data_1_len, out_data_2,
 101                                     block_size - out_data_1_len);
 102                         }
 103                         /* update offset */
 104                         out->cd_offset += block_size;
 105                 }
 106
 107                 /* Update pointer to next block of data to be processed. */
 108                 if (ctx->ecb_remainder_len != 0) {
 109                         datap += need;
 110                         ctx->ecb_remainder_len = 0;
 111                 } else {
 112                         datap += block_size;
 113                 }
 114
 115                 remainder = (size_t)&data[length] - (size_t)datap;
 116
 117                 /* Incomplete last block. */
 118                 if (remainder > 0 && remainder < block_size) {
 119                         bcopy(datap, ctx->ecb_remainder, remainder);
 120                         ctx->ecb_remainder_len = remainder;
 121                         ctx->ecb_copy_to = datap;
 122                         goto out;
 123                 }
 124                 ctx->ecb_copy_to = NULL;
 125
 126         } while (remainder > 0);
 127
 128 out:
 129         return (CRYPTO_SUCCESS);
 130 }
 131
 132 /* ARGSUSED */
 133 void *
 134 ecb_alloc_ctx(int kmflag)
 135 {
 136         ecb_ctx_t *ecb_ctx;
 137
 138         if ((ecb_ctx = kmem_zalloc(sizeof (ecb_ctx_t), kmflag)) == NULL)
 139                 return (NULL);
 140
 141         ecb_ctx->ecb_flags = ECB_MODE;
 142         return (ecb_ctx);
 143 }