1 /*************************************************
2 * Perl-Compatible Regular Expressions *
3 *************************************************/
4
5 /* PCRE is a library of functions to support regular expressions whose syntax
6 and semantics are as close as possible to those of the Perl 5 language.
7
8 Written by Philip Hazel
9 Copyright (c) 1997-2014 University of Cambridge
10
11 -----------------------------------------------------------------------------
12 Redistribution and use in source and binary forms, with or without
13 modification, are permitted provided that the following conditions are met:
14
15 * Redistributions of source code must retain the above copyright notice,
16 this list of conditions and the following disclaimer.
17
18 * Redistributions in binary form must reproduce the above copyright
19 notice, this list of conditions and the following disclaimer in the
20 documentation and/or other materials provided with the distribution.
21
22 * Neither the name of the University of Cambridge nor the names of its
23 contributors may be used to endorse or promote products derived from
24 this software without specific prior written permission.
25
26 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 POSSIBILITY OF SUCH DAMAGE.
37 -----------------------------------------------------------------------------
38 */
39
40
41 /* This module contains an internal function that tests a compiled pattern to
42 see if it was compiled with the opposite endianness. If so, it uses an
43 auxiliary local function to flip the appropriate bytes. */
44
45
46 #ifdef HAVE_CONFIG_H
47 #include "config.h"
48 #endif
49
50 #include "pcre_internal.h"
51
52
53 /*************************************************
54 * Swap byte functions *
55 *************************************************/
56
57 /* The following functions swap the bytes of a pcre_uint16
58 and pcre_uint32 value.
59
60 Arguments:
61 value any number
62
63 Returns: the byte swapped value
64 */
65
66 static pcre_uint32
swap_uint32(pcre_uint32 value)67 swap_uint32(pcre_uint32 value)
68 {
69 return ((value & 0x000000ff) << 24) |
70 ((value & 0x0000ff00) << 8) |
71 ((value & 0x00ff0000) >> 8) |
72 (value >> 24);
73 }
74
75 static pcre_uint16
swap_uint16(pcre_uint16 value)76 swap_uint16(pcre_uint16 value)
77 {
78 return (value >> 8) | (value << 8);
79 }
80
81
82 /*************************************************
83 * Test for a byte-flipped compiled regex *
84 *************************************************/
85
86 /* This function swaps the bytes of a compiled pattern usually
87 loaded form the disk. It also sets the tables pointer, which
88 is likely an invalid pointer after reload.
89
90 Arguments:
91 argument_re points to the compiled expression
92 extra_data points to extra data or is NULL
93 tables points to the character tables or NULL
94
95 Returns: 0 if the swap is successful, negative on error
96 */
97
98 #if defined COMPILE_PCRE8
pcre_pattern_to_host_byte_order(pcre * argument_re,pcre_extra * extra_data,const unsigned char * tables)99 PCRE_EXP_DECL int pcre_pattern_to_host_byte_order(pcre *argument_re,
100 pcre_extra *extra_data, const unsigned char *tables)
101 #elif defined COMPILE_PCRE16
102 PCRE_EXP_DECL int pcre16_pattern_to_host_byte_order(pcre16 *argument_re,
103 pcre16_extra *extra_data, const unsigned char *tables)
104 #elif defined COMPILE_PCRE32
105 PCRE_EXP_DECL int pcre32_pattern_to_host_byte_order(pcre32 *argument_re,
106 pcre32_extra *extra_data, const unsigned char *tables)
107 #endif
108 {
109 REAL_PCRE *re = (REAL_PCRE *)argument_re;
110 pcre_study_data *study;
111 #ifndef COMPILE_PCRE8
112 pcre_uchar *ptr;
113 int length;
114 #if defined SUPPORT_UTF && defined COMPILE_PCRE16
115 BOOL utf;
116 BOOL utf16_char;
117 #endif /* SUPPORT_UTF && COMPILE_PCRE16 */
118 #endif /* !COMPILE_PCRE8 */
119
120 if (re == NULL) return PCRE_ERROR_NULL;
121 if (re->magic_number == MAGIC_NUMBER)
122 {
123 if ((re->flags & PCRE_MODE) == 0) return PCRE_ERROR_BADMODE;
124 re->tables = tables;
125 return 0;
126 }
127
128 if (re->magic_number != REVERSED_MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC;
129 if ((swap_uint32(re->flags) & PCRE_MODE) == 0) return PCRE_ERROR_BADMODE;
130
131 re->magic_number = MAGIC_NUMBER;
132 re->size = swap_uint32(re->size);
133 re->options = swap_uint32(re->options);
134 re->flags = swap_uint32(re->flags);
135 re->limit_match = swap_uint32(re->limit_match);
136 re->limit_recursion = swap_uint32(re->limit_recursion);
137
138 #if defined COMPILE_PCRE8 || defined COMPILE_PCRE16
139 re->first_char = swap_uint16(re->first_char);
140 re->req_char = swap_uint16(re->req_char);
141 #elif defined COMPILE_PCRE32
142 re->first_char = swap_uint32(re->first_char);
143 re->req_char = swap_uint32(re->req_char);
144 #endif
145
146 re->max_lookbehind = swap_uint16(re->max_lookbehind);
147 re->top_bracket = swap_uint16(re->top_bracket);
148 re->top_backref = swap_uint16(re->top_backref);
149 re->name_table_offset = swap_uint16(re->name_table_offset);
150 re->name_entry_size = swap_uint16(re->name_entry_size);
151 re->name_count = swap_uint16(re->name_count);
152 re->ref_count = swap_uint16(re->ref_count);
153 re->tables = tables;
154
155 if (extra_data != NULL && (extra_data->flags & PCRE_EXTRA_STUDY_DATA) != 0)
156 {
157 study = (pcre_study_data *)extra_data->study_data;
158 study->size = swap_uint32(study->size);
159 study->flags = swap_uint32(study->flags);
160 study->minlength = swap_uint32(study->minlength);
161 }
162
163 #ifndef COMPILE_PCRE8
164 ptr = (pcre_uchar *)re + re->name_table_offset;
165 length = re->name_count * re->name_entry_size;
166 #if defined SUPPORT_UTF && defined COMPILE_PCRE16
167 utf = (re->options & PCRE_UTF16) != 0;
168 utf16_char = FALSE;
169 #endif /* SUPPORT_UTF && COMPILE_PCRE16 */
170
171 while(TRUE)
172 {
173 /* Swap previous characters. */
174 while (length-- > 0)
175 {
176 #if defined COMPILE_PCRE16
177 *ptr = swap_uint16(*ptr);
178 #elif defined COMPILE_PCRE32
179 *ptr = swap_uint32(*ptr);
180 #endif
181 ptr++;
182 }
183 #if defined SUPPORT_UTF && defined COMPILE_PCRE16
184 if (utf16_char)
185 {
186 if (HAS_EXTRALEN(ptr[-1]))
187 {
188 /* We know that there is only one extra character in UTF-16. */
189 *ptr = swap_uint16(*ptr);
190 ptr++;
191 }
192 }
193 utf16_char = FALSE;
194 #endif /* SUPPORT_UTF */
195
196 /* Get next opcode. */
197 length = 0;
198 #if defined COMPILE_PCRE16
199 *ptr = swap_uint16(*ptr);
200 #elif defined COMPILE_PCRE32
201 *ptr = swap_uint32(*ptr);
202 #endif
203 switch (*ptr)
204 {
205 case OP_END:
206 return 0;
207
208 #if defined SUPPORT_UTF && defined COMPILE_PCRE16
209 case OP_CHAR:
210 case OP_CHARI:
211 case OP_NOT:
212 case OP_NOTI:
213 case OP_STAR:
214 case OP_MINSTAR:
215 case OP_PLUS:
216 case OP_MINPLUS:
217 case OP_QUERY:
218 case OP_MINQUERY:
219 case OP_UPTO:
220 case OP_MINUPTO:
221 case OP_EXACT:
222 case OP_POSSTAR:
223 case OP_POSPLUS:
224 case OP_POSQUERY:
225 case OP_POSUPTO:
226 case OP_STARI:
227 case OP_MINSTARI:
228 case OP_PLUSI:
229 case OP_MINPLUSI:
230 case OP_QUERYI:
231 case OP_MINQUERYI:
232 case OP_UPTOI:
233 case OP_MINUPTOI:
234 case OP_EXACTI:
235 case OP_POSSTARI:
236 case OP_POSPLUSI:
237 case OP_POSQUERYI:
238 case OP_POSUPTOI:
239 case OP_NOTSTAR:
240 case OP_NOTMINSTAR:
241 case OP_NOTPLUS:
242 case OP_NOTMINPLUS:
243 case OP_NOTQUERY:
244 case OP_NOTMINQUERY:
245 case OP_NOTUPTO:
246 case OP_NOTMINUPTO:
247 case OP_NOTEXACT:
248 case OP_NOTPOSSTAR:
249 case OP_NOTPOSPLUS:
250 case OP_NOTPOSQUERY:
251 case OP_NOTPOSUPTO:
252 case OP_NOTSTARI:
253 case OP_NOTMINSTARI:
254 case OP_NOTPLUSI:
255 case OP_NOTMINPLUSI:
256 case OP_NOTQUERYI:
257 case OP_NOTMINQUERYI:
258 case OP_NOTUPTOI:
259 case OP_NOTMINUPTOI:
260 case OP_NOTEXACTI:
261 case OP_NOTPOSSTARI:
262 case OP_NOTPOSPLUSI:
263 case OP_NOTPOSQUERYI:
264 case OP_NOTPOSUPTOI:
265 if (utf) utf16_char = TRUE;
266 #endif
267 /* Fall through. */
268
269 default:
270 length = PRIV(OP_lengths)[*ptr] - 1;
271 break;
272
273 case OP_CLASS:
274 case OP_NCLASS:
275 /* Skip the character bit map. */
276 ptr += 32/sizeof(pcre_uchar);
277 length = 0;
278 break;
279
280 case OP_XCLASS:
281 /* Reverse the size of the XCLASS instance. */
282 ptr++;
283 #if defined COMPILE_PCRE16
284 *ptr = swap_uint16(*ptr);
285 #elif defined COMPILE_PCRE32
286 *ptr = swap_uint32(*ptr);
287 #endif
288 #ifndef COMPILE_PCRE32
289 if (LINK_SIZE > 1)
290 {
291 /* LINK_SIZE can be 1 or 2 in 16 bit mode. */
292 ptr++;
293 *ptr = swap_uint16(*ptr);
294 }
295 #endif
296 ptr++;
297 length = (GET(ptr, -LINK_SIZE)) - (1 + LINK_SIZE + 1);
298 #if defined COMPILE_PCRE16
299 *ptr = swap_uint16(*ptr);
300 #elif defined COMPILE_PCRE32
301 *ptr = swap_uint32(*ptr);
302 #endif
303 if ((*ptr & XCL_MAP) != 0)
304 {
305 /* Skip the character bit map. */
306 ptr += 32/sizeof(pcre_uchar);
307 length -= 32/sizeof(pcre_uchar);
308 }
309 break;
310 }
311 ptr++;
312 }
313 /* Control should never reach here in 16/32 bit mode. */
314 #else /* In 8-bit mode, the pattern does not need to be processed. */
315 return 0;
316 #endif /* !COMPILE_PCRE8 */
317 }
318
319 /* End of pcre_byte_order.c */
320