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
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Implementing a custom keys store.: XML Security Library Reference Manual</title>
<meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
<link rel="home" href="index.html" title="XML Security Library Reference Manual">
<link rel="up" href="xmlsec-notes-keysmngr.html" title="Keys manager.">
<link rel="prev" href="xmlsec-notes-keys-mngr-verify-decrypt.html" title="Using keys manager for verification/decryption.">
<link rel="next" href="xmlsec-notes-x509.html" title="Using X509 Certificates.">
<meta name="generator" content="GTK-Doc V1.34.0 (XML mode)">
<link rel="stylesheet" href="style.css" type="text/css">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle">
<td width="100%" align="left" class="shortcuts"></td>
<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td>
<td><a accesskey="u" href="xmlsec-notes-keysmngr.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td>
<td><a accesskey="p" href="xmlsec-notes-keys-mngr-verify-decrypt.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
<td><a accesskey="n" href="xmlsec-notes-x509.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
</tr></table>
<div class="sect1">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="xmlsec-notes-custom-keys-store"></a>Implementing a custom keys store.</h2></div></div></div>
<p>In many cases, a default built-in list based keys store
is not good enough. For example, XML Security Library (and
the built-in default keys store) have no synchronization and
you'll need to implement a custom keys store if you want to
add or remove keys while other threads use the store.</p>
<p>
</p>
<div class="example">
<a name="id-1.2.10.6.3.1"></a><p class="title"><b>Example 19. Creating a custom keys manager.</b></p>
<div class="example-contents">
<pre class="programlisting">
/**
* create_files_keys_mngr:
*
* Creates a files based keys manager: we assume that key name is
* the key file name,
*
* Returns pointer to newly created keys manager or NULL if an error occurs.
*/
xmlSecKeysMngrPtr
create_files_keys_mngr(void) {
xmlSecKeyStorePtr keysStore;
xmlSecKeysMngrPtr mngr;
/* create files based keys store */
keysStore = xmlSecKeyStoreCreate(files_keys_store_get_klass());
if(keysStore == NULL) {
fprintf(stderr, "Error: failed to create keys store.\n");
return(NULL);
}
/* create keys manager */
mngr = xmlSecKeysMngrCreate();
if(mngr == NULL) {
fprintf(stderr, "Error: failed to create keys manager.\n");
xmlSecKeyStoreDestroy(keysStore);
return(NULL);
}
/* add store to keys manager, from now on keys manager destroys the store if needed */
if(xmlSecKeysMngrAdoptKeysStore(mngr, keysStore) < 0) {
fprintf(stderr, "Error: failed to add keys store to keys manager.\n");
xmlSecKeyStoreDestroy(keysStore);
xmlSecKeysMngrDestroy(mngr);
return(NULL);
}
/* initialize crypto library specific data in keys manager */
if(xmlSecCryptoKeysMngrInit(mngr) < 0) {
fprintf(stderr, "Error: failed to initialize crypto data in keys manager.\n");
xmlSecKeysMngrDestroy(mngr);
return(NULL);
}
/* set the get key callback */
mngr->getKey = xmlSecKeysMngrGetKey;
return(mngr);
}
/****************************************************************************
*
* Files Keys Store: we assume that key's name (content of the
* <dsig:KeyName/> element is a name of the file with a key.
* Attention: this probably not a good solution for high traffic systems.
*
***************************************************************************/
static xmlSecKeyPtr files_keys_store_find_key (xmlSecKeyStorePtr store,
const xmlChar* name,
xmlSecKeyInfoCtxPtr keyInfoCtx);
static xmlSecKeyStoreKlass files_keys_store_klass = {
sizeof(xmlSecKeyStoreKlass),
sizeof(xmlSecKeyStore),
BAD_CAST "files-based-keys-store", /* const xmlChar* name; */
NULL, /* xmlSecKeyStoreInitializeMethod initialize; */
NULL, /* xmlSecKeyStoreFinalizeMethod finalize; */
files_keys_store_find_key, /* xmlSecKeyStoreFindKeyMethod findKey; */
/* reserved for the future */
NULL, /* void* reserved0; */
NULL, /* void* reserved1; */
};
/**
* files_keys_store_get_klass:
*
* The files based keys store klass: we assume that key name is the
* key file name,
*
* Returns files based keys store klass.
*/
xmlSecKeyStoreId
files_keys_store_get_klass(void) {
return(&files_keys_store_klass);
}
/**
* files_keys_store_find_key:
* @store: the pointer to default keys store.
* @name: the desired key name.
* @keyInfoCtx: the pointer to <dsig:KeyInfo/> node processing context.
*
* Lookups key in the @store.
*
* Returns pointer to key or NULL if key not found or an error occurs.
*/
static xmlSecKeyPtr
files_keys_store_find_key(xmlSecKeyStorePtr store, const xmlChar* name, xmlSecKeyInfoCtxPtr keyInfoCtx) {
xmlSecKeyPtr key;
const xmlChar* p;
assert(store);
assert(keyInfoCtx);
/* it's possible to do not have the key name or desired key type
* but we could do nothing in this case */
if((name == NULL) || (keyInfoCtx->keyReq.keyId == xmlSecKeyDataIdUnknown)){
return(NULL);
}
/* we don't want to open files in a folder other than "current";
* to prevent it limit the characters in the key name to alpha/digit,
* '.', '-' or '_'.
*/
for(p = name; (*p) != '\0'; ++p) {
if(!isalnum((*p)) && ((*p) != '.') && ((*p) != '-') && ((*p) != '_')) {
return(NULL);
}
}
if((keyInfoCtx->keyReq.keyId == xmlSecKeyDataDsaId) || (keyInfoCtx->keyReq.keyId == xmlSecKeyDataRsaId)) {
/* load key from a pem file, if key is not found then it's an error (is it?) */
key = xmlSecCryptoAppKeyLoad(name, xmlSecKeyDataFormatPem, NULL, NULL, NULL);
if(key == NULL) {
fprintf(stderr,"Error: failed to load pem key from \"%s\"\n", name);
return(NULL);
}
} else {
/* otherwise it's a binary key, if key is not found then it's an error (is it?) */
key = xmlSecKeyReadBinaryFile(keyInfoCtx->keyReq.keyId, name);
if(key == NULL) {
fprintf(stderr,"Error: failed to load key from binary file \"%s\"\n", name);
return(NULL);
}
}
/* set key name */
if(xmlSecKeySetName(key, name) < 0) {
fprintf(stderr,"Error: failed to set key name for key from \"%s\"\n", name);
xmlSecKeyDestroy(key);
return(NULL);
}
return(key);
}
</pre>
<p><a class="link" href="xmlsec-custom-keys-manager.html#xmlsec-example-decrypt3" title="decrypt3.c">Full program listing</a></p>
</div>
</div>
<p><br class="example-break">
</p>
</div>
<div class="footer">
<hr>Generated by GTK-Doc V1.34.0</div>
</body>
</html>
|
