1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta content="Apache Forrest" name="Generator">
<meta name="Forrest-version" content="0.6">
<meta name="Forrest-skin-name" content="pelt">
<title>Frequently Asked Questions - C++</title>
<link type="text/css" href="../skin/basic.css" rel="stylesheet">
<link media="screen" type="text/css" href="../skin/screen.css" rel="stylesheet">
<link media="print" type="text/css" href="../skin/print.css" rel="stylesheet">
<link type="text/css" href="../skin/profile.css" rel="stylesheet">
<script src="../skin/getBlank.js" language="javascript" type="text/javascript"></script><script src="../skin/getMenu.js" language="javascript" type="text/javascript"></script><script src="../skin/fontsize.js" language="javascript" type="text/javascript"></script>
</head>
<body onload="init()">
<script type="text/javascript">ndeSetTextSize();</script>
<div id="top">
<!--+
|breadtrail
+-->
<div class="breadtrail">
<a href="http://www.apache.org/">apache</a> > <a href="http://xml.apache.org/">xml.apache</a><script src="../skin/breadcrumbs.js" language="JavaScript" type="text/javascript"></script>
</div>
<!--+
|header
+-->
<div class="header">
<!--+
|start group logo
+-->
<div class="grouplogo">
<a href="http:///xml.apache.org"><img class="logoImage" alt="Apache XML" src="../images/group-logo.gif"></a>
</div>
<!--+
|end group logo
+-->
<!--+
|start Project Logo
+-->
<div class="projectlogo">
<a href="http://xml.apache.org/security"><img class="logoImage" alt="Apache XML Security" src="../images/project-logo.gif"></a>
</div>
<!--+
|end Project Logo
+-->
<!--+
|start Search
+-->
<div class="searchbox">
<form action="http://www.google.com/search" method="get" class="roundtopsmall">
<input value="xml.apache.org/security" name="sitesearch" type="hidden"><input onFocus="getBlank (this, 'Search the site with google:');" value="Search the site with google:" size="25" name="q" id="query" type="text">
<input name="Search" value="Search" type="submit">
</form>
</div>
<!--+
|end search
+-->
<!--+
|start Tabs
+-->
<ul id="tabs">
<li>
<a class="base-not-selected" href="../index.html">Home</a>
</li>
<li>
<a class="base-not-selected" href="../Java/index.html">Java</a>
</li>
<li class="current">
<a class="base-selected" href="../c/index.html">C++</a>
</li>
</ul>
<!--+
|end Tabs
+-->
</div>
</div>
<div id="main">
<div id="publishedStrip">
<!--+
|start Subtabs
+-->
<div id="level2tabs"></div>
<!--+
|end Endtabs
+-->
<script type="text/javascript" language="JavaScript"><!--
document.write("Published: " + document.lastModified);
// --></script>
</div>
<!--+
|breadtrail
+-->
<div class="breadtrail">
</div>
<!--+
|start Menu, mainarea
+-->
<!--+
|start Menu
+-->
<div id="menu">
<div onclick="SwitchMenu('menu_selected_1.1', '../skin/')" id="menu_selected_1.1Title" class="menutitle" style="background-image: url('../skin/images/chapter_open.gif');">C++</div>
<div id="menu_selected_1.1" class="selectedmenuitemgroup" style="display: block;">
<div class="menuitem">
<a title="" href="../c/index.html">Index</a>
</div>
<div class="menuitem">
<a title="" href="../c/installation.html">Installation</a>
</div>
<div class="menupage">
<div class="menupagetitle">FAQs</div>
</div>
<div class="menuitem">
<a title="" href="../c/apiDocs/index.html">API Docs</a>
</div>
<div class="menuitem">
<a title="" href="http://nagoya.apache.org/~blautenb/xml-security-c/apiDocs/">Nightly API build</a>
</div>
<div class="menuitem">
<a title="" href="../c/tools.html">Tools</a>
</div>
<div class="menuitem">
<a title="" href="../c/releases.html">Release Information</a>
</div>
<div class="menuitem">
<a title="" href="../c/credits.html">Credits</a>
</div>
<div class="menuitem">
<a title="" href="../c/interop.html">Interoperability</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.2', '../skin/')" id="menu_1.2Title" class="menutitle">Programming</div>
<div id="menu_1.2" class="menuitemgroup">
<div class="menuitem">
<a title="" href="../c/programming.html">Signatures</a>
</div>
<div class="menuitem">
<a title="" href="../c/prog_enc.html">Encryption</a>
</div>
</div>
<div id="credit"></div>
<div id="roundbottom">
<img style="display: none" class="corner" height="15" width="15" alt="" src="../skin/images/rc-b-l-15-1body-2menu-3menu.png"></div>
<!--+
|alternative credits
+-->
</div>
<!--+
|end Menu
+-->
<!--+
|start content
+-->
<div id="content">
<div id="skinconf-txtlink"></div>
<h1>Frequently Asked Questions - C++</h1>
<a name="N10008"></a><a name="Questions"></a>
<h2 class="h3">Questions</h2>
<div class="section">
<a name="N1000C"></a><a name="general_c"></a>
<h3 class="h4">1. Compiling and Using the Library</h3>
<a name="N10010"></a><a name="openssl_c"></a>
<h4 class="faq">1.1.
Is OpenSSL required?
</h4>
<div align="right">
<a href="#openssl_c-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
The main development work for the library is done using OpenSSL, so
this is the recommended option. However, a Windows
Crypto API interface is also now provided.
</p>
<p>
It is also possible to implement interfaces for other cryptographic
libraries and pass them into the xml-security-c library during
initialisation (via the <em>XSECPlatformUtils::Initialise()</em>
call).
</p>
</div>
<a name="N1001E"></a><a name="openssl2_c"></a>
<h4 class="faq">1.2.
Does the library provide a full C++ wrapper for OpenSSL?
</h4>
<div align="right">
<a href="#openssl2_c-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
The C++ crypto interface layer provided for the library provides only
the smallest subset of cryptographic functions necessary for the
library to make calls to the provided library. Applications will
need to work directly with OpenSSL (or other libraries) to read and
manipulate encryption keys that should then be wrapped in XSECCrypto*
objects and passed into the library.
</p>
</div>
<a name="N10026"></a><a name="wincapi_c"></a>
<h4 class="faq">1.3.
What is WinCAPI?
</h4>
<div align="right">
<a href="#wincapi_c-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
WinCAPI is the developmental interface being built to give
users of the library access to the Windows Cryptographic library.
</p>
<p>
It is <em>not</em> a C API wrapper for the overall library.
</p>
</div>
<a name="N10034"></a><a name="xalan_c"></a>
<h4 class="faq">1.4.
Is Xalan required?
</h4>
<div align="right">
<a href="#xalan_c-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
The library can be compiled without linking to Xalan-c. However
doing so will disable support for XPath and XSLT transformations.
</p>
<p>
To disable Xalan-c support either use --without-xalan when running
configure on UNIX, or use the VC++ "without Xalan" settings.
</p>
</div>
<a name="N1003F"></a><a name="oldXalanC"></a>
<h4 class="faq">1.5.
Are versions of Xalan prior to 1.6 supported?
</h4>
<div align="right">
<a href="#oldXalanC-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
No. Whilst the functionality required is available in prior
versions, the location of include files changed in 1.6. A
decision was made in version 1.0.0 of xml-security-c to
update the source to support these new locations.
</p>
</div>
<a name="N10047"></a><a name="elementorder"></a>
<h4 class="faq">1.6.
I sign a document and when I try to verify using the same key, it fails
</h4>
<div align="right">
<a href="#elementorder-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
After you have created the XMLSignature object, before you sign the
document, you <em>must</em> embed the signature element in the owning
document (which is returned by the call to
<span class="codefrag">DSIGSignature::createBlankSignature(...)</span>) before
calling the <span class="codefrag">DSIGSignature::sign()</span> method,
</p>
<p>
During canonicalisation of the SignedInfo element, the library looks
at the parent and ancestor nodes of the Signature element to find
any namespaces that the SignedInfo node has inherited. Any that are
found are embedded in the canonical form of the SignedInfo. (This
is not true when Exclusive Canonicalisation is used, but it is still
good practice to insert the element node prior to the sign()
method being called).
</p>
<p>
If you have not embedded the signature node in the document, it will
not have any parent or ancestor nodes, so it will not inherit their
namespaces. If you then embed it in the document and call <span class="codefrag">
verify()</span>, the namespaces will be found and the canonical
form of SignedInfo will be different to that generated during
<span class="codefrag">sign()</span>.
</p>
</div>
<a name="N10064"></a><a name="ids"></a>
<h4 class="faq">1.7.
How does the library identify Id attributes?
</h4>
<div align="right">
<a href="#ids-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
During a signing operation, finding the correct Id attribute is
vital. Should the wrong Id Attribute be used, the wrong
part of the document will be identified, and what the user signs
will not be what they expect to sign.
</p>
<p>
The preferred method (and the method the library uses first) of
finding an Id is via the DOM Level 2 call
<em>DOMDocument::getElementById()</em>. This indicates to the
library that the Id has been explicitly identified via a schema,
DTD or during document building. However, if this call fails, the
library will then search the document for attributes named "Id" or
"id" with the appropriate value. The first one found will be used
as document fragment identifier.
</p>
<p>
As of version 1.2, the library also provides methods to allow
callers to set additional Id attribute names. This can be
done in one of two ways.
<em>DSIGSignature::registerIdAttributeName()</em> will register
a new name that will not be matched to a namespace.
<em>DSIGDSignature::registerIdAttribiteNameNS()</em> will
register an attribute name together with the namespace in
which the attribute resides.
</p>
<p>
As this is a potential security exposure, this behaviour can be
disabled using a call to
<em>DISGSignatures::setIdByAttributeName(false)</em>. There are
also methods provided to modify the list of attributes that will
be searched. However it is recommended that these methods not be
used, and DOM attributes of Type=ID be used.
</p>
<div class="frame warning">
<div class="label">Warning</div>
<div class="content">
In version 1.1 and above, the library defaults to searching for Id
attributes by name if a search by Id fails. As this is a potential
security risk, this behaviour may be changed in a future version
of the library.
</div>
</div>
</div>
<a name="N10084"></a><a name="xkms_support"></a>
<h4 class="faq">1.8.
What parts of the XKMS specification does the library support?
</h4>
<div align="right">
<a href="#xkms_support-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
The library currently supports X-KISS (XML Key Information
Service Specification) message generation and processing.
Support for X-KRSS (XML Key Registration Service Specification)
will be provided in version 1.3 of the library.
</p>
</div>
<a name="N1008C"></a><a name="xkms_client"></a>
<h4 class="faq">1.9.
Does the library provide a programmatic XKMS client?
</h4>
<div align="right">
<a href="#xkms_client-menu">^</a>
</div>
<div style="margin-left: 15px">
<p>
Not yet. A command line tool <em>xklient</em> is provided for
generating and processing messages. This can be used as an
example for processing XKMS messages.
</p>
<p>
A programmatic client will be provided in version 1.3 of the C++
library.
</p>
</div>
</div>
</div>
<!--+
|end content
+-->
<div class="clearboth"> </div>
</div>
<div id="footer">
<!--+
|start bottomstrip
+-->
<div class="lastmodified">
<script type="text/javascript"><!--
document.write("Last Published: " + document.lastModified);
// --></script>
</div>
<div class="copyright">
Copyright © 2002-2005 The Apache Software Foundation.</div>
<!--+
|end bottomstrip
+-->
</div>
</body>
</html>
|
