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
|
/*++
Copyright (c) 1989 Microsoft Corporation
Module Name:
PrefxSup.c
Abstract:
This module implements the Named Pipe Prefix support routines
Author:
Gary Kimura [GaryKi] 13-Feb-1990
Revision History:
--*/
#include "NpProcs.h"
//
// The Bug check file id for this module
//
#define BugCheckFileId (NPFS_BUG_CHECK_PREFXSUP)
//
// The debug trace level for this module
//
#define Dbg (DEBUG_TRACE_PREFXSUP)
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, NpFindPrefix)
#pragma alloc_text(PAGE, NpFindRelativePrefix)
#endif
PFCB
NpFindPrefix (
IN PUNICODE_STRING String,
IN BOOLEAN CaseInsensitive,
OUT PUNICODE_STRING RemainingPart
)
/*++
Routine Description:
This routine searches the FCBs/DCBs of a volume and locates the
FCB/DCB with longest matching prefix for the given input string. The
search is relative to the root of the volume. So all names must start
with a "\".
Arguments:
String - Supplies the input string to search for
CaseInsensitive - Specifies if the search is to be done case sensitive
(FALSE) or insensitive (TRUE)
RemainingPart - Returns the string when the prefix no longer matches.
For example, if the input string is "\alpha\beta" only matches the
root directory then the remaining string is "alpha\beta". If the
same string matches a DCB for "\alpha" then the remaining string is
"beta".
Return Value:
PFCB - Returns a pointer to either an FCB or a DCB whichever is the
longest matching prefix.
--*/
{
PUNICODE_PREFIX_TABLE_ENTRY PrefixTableEntry;
PFCB Fcb;
PAGED_CODE();
DebugTrace(+1, Dbg, "NpFindPrefix, NpVcb = %08lx\n", NpVcb);
DebugTrace( 0, Dbg, " String = %Z\n", String);
//
// Find the longest matching prefix
//
PrefixTableEntry = RtlFindUnicodePrefix( &NpVcb->PrefixTable,
String,
CaseInsensitive );
//
// If we didn't find one then it's an error
//
if (PrefixTableEntry == NULL) {
DebugDump("Error looking up a prefix", 0, NpVcb);
NpBugCheck( 0, 0, 0 );
}
//
// Get a pointer to the Fcb containing the prefix table entry
//
Fcb = CONTAINING_RECORD( PrefixTableEntry, FCB, PrefixTableEntry );
//
// Tell the caller how many characters we were able to match. We first
// set the remaining part to the original string minus the matched
// prefix, then we check if the remaining part starts with a backslash
// and if it does then we remove the backslash from the remaining string.
//
RemainingPart->Length = String->Length - Fcb->FullFileName.Length;
RemainingPart->MaximumLength = RemainingPart->Length;
RemainingPart->Buffer = &String->Buffer[ Fcb->FullFileName.Length/sizeof(WCHAR) ];
if ((RemainingPart->Length > 0) &&
(RemainingPart->Buffer[0] == L'\\')) {
RemainingPart->Length -= sizeof(WCHAR);
RemainingPart->MaximumLength -= sizeof(WCHAR);
RemainingPart->Buffer += 1;
}
DebugTrace(0, Dbg, "RemainingPart set to %Z\n", RemainingPart);
//
// And return to our caller
//
DebugTrace(-1, Dbg, "NpFindPrefix -> %08lx\n", Fcb);
return Fcb;
}
PFCB
NpFindRelativePrefix (
IN PDCB Dcb,
IN PUNICODE_STRING String,
IN BOOLEAN CaseInsensitive,
OUT PUNICODE_STRING RemainingPart
)
/*++
Routine Description:
This routine searches the FCBs/DCBs of a volume and locates the
FCB/DCB with longest matching prefix for the given input string. The
search is relative to a input DCB, and must not start with a leading "\"
All searching is done case insensitive.
Arguments:
Dcb - Supplies the Dcb to start searching from
String - Supplies the input string to search for
CaseInsensitive - Specifies if the search is to be done case sensitive
(FALSE) or insensitive (TRUE)
RemainingPart - Returns the index into the string when the prefix no
longer matches. For example, if the input string is "beta\gamma"
and the input Dcb is for "\alpha" and we only match beta then
the remaining string is "gamma".
Return Value:
PFCB - Returns a pointer to either an FCB or a DCB whichever is the
longest matching prefix.
--*/
{
ULONG NameLength;
PWCH Name;
UNICODE_STRING FullString;
PWCH Temp;
PFCB Fcb;
PAGED_CODE();
DebugTrace(+1, Dbg, "NpFindRelativePrefix, Dcb = %08lx\n", Dcb);
DebugTrace( 0, Dbg, "String = %08lx\n", String);
//
// Initialize the Temp buffer to null so in our termination handler
// we'll know to release pool
//
Temp = NULL;
try {
//
// We first need to build the complete name and then do a relative
// search from the root
//
NameLength = String->Length;
Name = String->Buffer;
ASSERT(NodeType(Dcb) == NPFS_NTC_ROOT_DCB);
Temp = FsRtlAllocatePool( PagedPool, NameLength + 2*sizeof(WCHAR) );
Temp[0] = L'\\';
RtlCopyMemory( &Temp[1], Name, NameLength );
Temp[NameLength/sizeof(WCHAR) + 1] = L'\0';
RtlInitUnicodeString( &FullString, Temp );
//
// Find the prefix relative to the volume
//
Fcb = NpFindPrefix( &FullString,
CaseInsensitive,
RemainingPart );
//
// Now adjust the remaining part to take care of the relative
// volume prefix.
//
RemainingPart->Buffer = &String->Buffer[(String->Length -
RemainingPart->Length) / sizeof(WCHAR)];
DebugTrace(0, Dbg, "RemainingPart set to %Z\n", RemainingPart);
} finally {
//
// Release the pool if we it was allocated
//
if (Temp != NULL) { ExFreePool( Temp ); }
//
// And return to our caller
//
DebugTrace(-1, Dbg, "NpFindRelativePrefix -> %08lx\n", Fcb);
}
return Fcb;
}
|
