1 /*
2 * ccdigest_update.c
3 * corecrypto
4 *
5 * Created on 11/30/2010
6 *
7 * Copyright (c) 2010,2011,2014,2015 Apple Inc. All rights reserved.
8 *
9 *
10 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
11 *
12 * This file contains Original Code and/or Modifications of Original Code
13 * as defined in and that are subject to the Apple Public Source License
14 * Version 2.0 (the 'License'). You may not use this file except in
15 * compliance with the License. The rights granted to you under the License
16 * may not be used to create, or enable the creation or redistribution of,
17 * unlawful or unlicensed copies of an Apple operating system, or to
18 * circumvent, violate, or enable the circumvention or violation of, any
19 * terms of an Apple operating system software license agreement.
20 *
21 * Please obtain a copy of the License at
22 * http://www.opensource.apple.com/apsl/ and read it before using this file.
23 *
24 * The Original Code and all software distributed under the License are
25 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
26 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
27 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
28 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
29 * Please see the License for the specific language governing rights and
30 * limitations under the License.
31 *
32 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
33 */
34
35 #include <corecrypto/ccdigest.h>
36 #include <corecrypto/cc_priv.h>
37
38 void
ccdigest_update(const struct ccdigest_info * di,ccdigest_ctx_t ctx,size_t len,const void * data)39 ccdigest_update(const struct ccdigest_info *di, ccdigest_ctx_t ctx, size_t len, const void *data)
40 {
41 const char * data_ptr = data;
42 size_t nblocks, nbytes;
43
44 // Sanity check to recover from ctx corruptions.
45 if (ccdigest_num(di, ctx) >= di->block_size) {
46 ccdigest_num(di, ctx) = 0;
47 }
48
49 while (len > 0) {
50 if (ccdigest_num(di, ctx) == 0 && len > di->block_size) {
51 if (di->block_size == 1 << 6) { // md5 & sha1 & sha256
52 nblocks = len >> 6;
53 nbytes = nblocks << 6;
54 } else if (di->block_size == 1 << 7) { // sha384 & sha512
55 nblocks = len >> 7;
56 nbytes = nblocks << 7;
57 } else {
58 nblocks = len / di->block_size;
59 nbytes = nblocks * di->block_size;
60 }
61
62 di->compress(ccdigest_state(di, ctx), nblocks, data_ptr);
63 len -= nbytes;
64 data_ptr += nbytes;
65 ccdigest_nbits(di, ctx) += (uint64_t) (nbytes) * 8;
66 } else {
67 size_t n = CC_MIN(di->block_size - ccdigest_num(di, ctx), len);
68 cc_memcpy(ccdigest_data(di, ctx) + ccdigest_num(di, ctx), data_ptr, n);
69 /* typecast: less than block size, will always fit into an int */
70 ccdigest_num(di, ctx) += (unsigned int)n;
71 len -= n;
72 data_ptr += n;
73 if (ccdigest_num(di, ctx) == di->block_size) {
74 di->compress(ccdigest_state(di, ctx), 1, ccdigest_data(di, ctx));
75 ccdigest_nbits(di, ctx) += ccdigest_num(di, ctx) * 8;
76 ccdigest_num(di, ctx) = 0;
77 }
78 }
79 }
80 }
81