1/*
2 * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24
25//
26// blob - generic extensible binary blob frame
27//
28#include "blob.h"
29#include <security_utilities/unix++.h>
30
31namespace Security {
32
33
34//
35// Content access and validation calls
36//
37char *BlobCore::stringAt(Offset offset)
38{
39	char *s = at<char>(offset);
40	if (offset < this->length() && memchr(s, 0, this->length() - offset))
41		return s;
42	else
43		return NULL;
44}
45
46const char *BlobCore::stringAt(Offset offset) const
47{
48	const char *s = at<const char>(offset);
49	if (offset < this->length() && memchr(s, 0, this->length() - offset))
50		return s;
51	else
52		return NULL;
53}
54
55
56//
57// Read a blob from a standard file stream.
58// Reads in one pass, so it's suitable for transmission over pipes and networks.
59// The blob is allocated with malloc(3).
60// On error, sets errno and returns NULL; in which case the input stream may
61// be partially consumed.
62//
63BlobCore *BlobCore::readBlob(int fd, size_t offset, uint32_t magic, size_t minSize, size_t maxSize)
64{
65	BlobCore header;
66	if (::pread(fd, &header, sizeof(header), offset) == sizeof(header))
67		if (header.validateBlob(magic, minSize, maxSize))
68			if (BlobCore *blob = (BlobCore *)malloc(header.length())) {
69				memcpy(blob, &header, sizeof(header));
70				size_t remainder = header.length() - sizeof(header);
71				if (::pread(fd, blob+1, remainder, offset + sizeof(header)) == ssize_t(remainder))
72					return blob;
73				free(blob);
74				errno = EINVAL;
75			}
76	return NULL;
77}
78
79BlobCore *BlobCore::readBlob(int fd, uint32_t magic, size_t minSize, size_t maxSize)
80{
81	BlobCore header;
82	if (::read(fd, &header, sizeof(header)) == sizeof(header))
83		if (header.validateBlob(magic, minSize, maxSize))
84			if (BlobCore *blob = (BlobCore *)malloc(header.length())) {
85				memcpy(blob, &header, sizeof(header));
86				size_t remainder = header.length() - sizeof(header);
87				if (::read(fd, blob+1, remainder) == ssize_t(remainder))
88					return blob;
89				free(blob);
90				errno = EINVAL;
91			}
92	return NULL;
93}
94
95BlobCore *BlobCore::readBlob(std::FILE *file, uint32_t magic, size_t minSize, size_t maxSize)
96{
97	BlobCore header;
98	if (::fread(&header, sizeof(header), 1, file) == 1)
99		if (header.validateBlob(magic, minSize, maxSize))
100			if (BlobCore *blob = (BlobCore *)malloc(header.length())) {
101				memcpy(blob, &header, sizeof(header));
102				if (::fread(blob+1, header.length() - sizeof(header), 1, file) == 1)
103					return blob;
104				free(blob);
105				errno = EINVAL;
106			}
107	return NULL;
108}
109
110
111//
112// BlobWrappers
113//
114BlobWrapper *BlobWrapper::alloc(size_t length, Magic magic /* = _magic */)
115{
116	size_t wrapLength = length + sizeof(BlobCore);
117	if (wrapLength < length)	// overflow
118		return NULL;
119	BlobWrapper *w = (BlobWrapper *)malloc(wrapLength);
120	if (w)
121		w->BlobCore::initialize(magic, wrapLength);
122	return w;
123}
124
125BlobWrapper *BlobWrapper::alloc(const void *data, size_t length, Magic magic /* = _magic */)
126{
127	BlobWrapper *w = alloc(length, magic);
128	if (w)
129		memcpy(w->data(), data, w->length());
130	return w;
131}
132
133
134}	// Security
135