Annotation of embedaddon/php/ext/pcre/pcrelib/pcre_valid_utf8.c, revision 1.1.1.2
1.1 misho 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
1.1.1.2 ! misho 9: Copyright (c) 1997-2012 University of Cambridge
1.1 misho 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 for validating UTF-8 character
42: strings. */
43:
44:
1.1.1.2 ! misho 45: #ifdef HAVE_CONFIG_H
1.1 misho 46: #include "config.h"
1.1.1.2 ! misho 47: #endif
1.1 misho 48:
49: #include "pcre_internal.h"
50:
51:
52: /*************************************************
53: * Validate a UTF-8 string *
54: *************************************************/
55:
56: /* This function is called (optionally) at the start of compile or match, to
1.1.1.2 ! misho 57: check that a supposed UTF-8 string is actually valid. The early check means
1.1 misho 58: that subsequent code can assume it is dealing with a valid string. The check
1.1.1.2 ! misho 59: can be turned off for maximum performance, but the consequences of supplying an
! 60: invalid string are then undefined.
1.1 misho 61:
62: Originally, this function checked according to RFC 2279, allowing for values in
63: the range 0 to 0x7fffffff, up to 6 bytes long, but ensuring that they were in
64: the canonical format. Once somebody had pointed out RFC 3629 to me (it
65: obsoletes 2279), additional restrictions were applied. The values are now
66: limited to be between 0 and 0x0010ffff, no more than 4 bytes long, and the
1.1.1.2 ! misho 67: subrange 0xd000 to 0xdfff is excluded. However, the format of 5-byte and 6-byte
! 68: characters is still checked.
! 69:
! 70: From release 8.13 more information about the details of the error are passed
! 71: back in the returned value:
! 72:
! 73: PCRE_UTF8_ERR0 No error
! 74: PCRE_UTF8_ERR1 Missing 1 byte at the end of the string
! 75: PCRE_UTF8_ERR2 Missing 2 bytes at the end of the string
! 76: PCRE_UTF8_ERR3 Missing 3 bytes at the end of the string
! 77: PCRE_UTF8_ERR4 Missing 4 bytes at the end of the string
! 78: PCRE_UTF8_ERR5 Missing 5 bytes at the end of the string
! 79: PCRE_UTF8_ERR6 2nd-byte's two top bits are not 0x80
! 80: PCRE_UTF8_ERR7 3rd-byte's two top bits are not 0x80
! 81: PCRE_UTF8_ERR8 4th-byte's two top bits are not 0x80
! 82: PCRE_UTF8_ERR9 5th-byte's two top bits are not 0x80
! 83: PCRE_UTF8_ERR10 6th-byte's two top bits are not 0x80
! 84: PCRE_UTF8_ERR11 5-byte character is not permitted by RFC 3629
! 85: PCRE_UTF8_ERR12 6-byte character is not permitted by RFC 3629
! 86: PCRE_UTF8_ERR13 4-byte character with value > 0x10ffff is not permitted
! 87: PCRE_UTF8_ERR14 3-byte character with value 0xd000-0xdfff is not permitted
! 88: PCRE_UTF8_ERR15 Overlong 2-byte sequence
! 89: PCRE_UTF8_ERR16 Overlong 3-byte sequence
! 90: PCRE_UTF8_ERR17 Overlong 4-byte sequence
! 91: PCRE_UTF8_ERR18 Overlong 5-byte sequence (won't ever occur)
! 92: PCRE_UTF8_ERR19 Overlong 6-byte sequence (won't ever occur)
! 93: PCRE_UTF8_ERR20 Isolated 0x80 byte (not within UTF-8 character)
! 94: PCRE_UTF8_ERR21 Byte with the illegal value 0xfe or 0xff
! 95: PCRE_UTF8_ERR22 Non-character
1.1 misho 96:
97: Arguments:
98: string points to the string
99: length length of string, or -1 if the string is zero-terminated
1.1.1.2 ! misho 100: errp pointer to an error position offset variable
1.1 misho 101:
1.1.1.2 ! misho 102: Returns: = 0 if the string is a valid UTF-8 string
! 103: > 0 otherwise, setting the offset of the bad character
1.1 misho 104: */
105:
106: int
1.1.1.2 ! misho 107: PRIV(valid_utf)(PCRE_PUCHAR string, int length, int *erroroffset)
1.1 misho 108: {
1.1.1.2 ! misho 109: #ifdef SUPPORT_UTF
! 110: register PCRE_PUCHAR p;
1.1 misho 111:
112: if (length < 0)
113: {
114: for (p = string; *p != 0; p++);
1.1.1.2 ! misho 115: length = (int)(p - string);
1.1 misho 116: }
117:
118: for (p = string; length-- > 0; p++)
119: {
1.1.1.2 ! misho 120: register pcre_uchar ab, c, d;
! 121: pcre_uint32 v = 0;
! 122:
! 123: c = *p;
! 124: if (c < 128) continue; /* ASCII character */
! 125:
! 126: if (c < 0xc0) /* Isolated 10xx xxxx byte */
! 127: {
! 128: *erroroffset = (int)(p - string);
! 129: return PCRE_UTF8_ERR20;
! 130: }
! 131:
! 132: if (c >= 0xfe) /* Invalid 0xfe or 0xff bytes */
! 133: {
! 134: *erroroffset = (int)(p - string);
! 135: return PCRE_UTF8_ERR21;
! 136: }
! 137:
! 138: ab = PRIV(utf8_table4)[c & 0x3f]; /* Number of additional bytes */
! 139: if (length < ab)
! 140: {
! 141: *erroroffset = (int)(p - string); /* Missing bytes */
! 142: return ab - length; /* Codes ERR1 to ERR5 */
! 143: }
! 144: length -= ab; /* Length remaining */
1.1 misho 145:
146: /* Check top bits in the second byte */
147:
1.1.1.2 ! misho 148: if (((d = *(++p)) & 0xc0) != 0x80)
! 149: {
! 150: *erroroffset = (int)(p - string) - 1;
! 151: return PCRE_UTF8_ERR6;
! 152: }
! 153:
! 154: /* For each length, check that the remaining bytes start with the 0x80 bit
! 155: set and not the 0x40 bit. Then check for an overlong sequence, and for the
! 156: excluded range 0xd800 to 0xdfff. */
1.1 misho 157:
158: switch (ab)
159: {
1.1.1.2 ! misho 160: /* 2-byte character. No further bytes to check for 0x80. Check first byte
! 161: for for xx00 000x (overlong sequence). */
1.1 misho 162:
1.1.1.2 ! misho 163: case 1: if ((c & 0x3e) == 0)
! 164: {
! 165: *erroroffset = (int)(p - string) - 1;
! 166: return PCRE_UTF8_ERR15;
! 167: }
! 168: break;
1.1 misho 169:
1.1.1.2 ! misho 170: /* 3-byte character. Check third byte for 0x80. Then check first 2 bytes
! 171: for 1110 0000, xx0x xxxx (overlong sequence) or
! 172: 1110 1101, 1010 xxxx (0xd800 - 0xdfff) */
1.1 misho 173:
174: case 2:
1.1.1.2 ! misho 175: if ((*(++p) & 0xc0) != 0x80) /* Third byte */
! 176: {
! 177: *erroroffset = (int)(p - string) - 2;
! 178: return PCRE_UTF8_ERR7;
! 179: }
! 180: if (c == 0xe0 && (d & 0x20) == 0)
! 181: {
! 182: *erroroffset = (int)(p - string) - 2;
! 183: return PCRE_UTF8_ERR16;
! 184: }
! 185: if (c == 0xed && d >= 0xa0)
! 186: {
! 187: *erroroffset = (int)(p - string) - 2;
! 188: return PCRE_UTF8_ERR14;
! 189: }
! 190: v = ((c & 0x0f) << 12) | ((d & 0x3f) << 6) | (*p & 0x3f);
1.1 misho 191: break;
192:
1.1.1.2 ! misho 193: /* 4-byte character. Check 3rd and 4th bytes for 0x80. Then check first 2
! 194: bytes for for 1111 0000, xx00 xxxx (overlong sequence), then check for a
! 195: character greater than 0x0010ffff (f4 8f bf bf) */
1.1 misho 196:
197: case 3:
1.1.1.2 ! misho 198: if ((*(++p) & 0xc0) != 0x80) /* Third byte */
! 199: {
! 200: *erroroffset = (int)(p - string) - 2;
! 201: return PCRE_UTF8_ERR7;
! 202: }
! 203: if ((*(++p) & 0xc0) != 0x80) /* Fourth byte */
! 204: {
! 205: *erroroffset = (int)(p - string) - 3;
! 206: return PCRE_UTF8_ERR8;
! 207: }
! 208: if (c == 0xf0 && (d & 0x30) == 0)
! 209: {
! 210: *erroroffset = (int)(p - string) - 3;
! 211: return PCRE_UTF8_ERR17;
! 212: }
! 213: if (c > 0xf4 || (c == 0xf4 && d > 0x8f))
! 214: {
! 215: *erroroffset = (int)(p - string) - 3;
! 216: return PCRE_UTF8_ERR13;
! 217: }
! 218: v = ((c & 0x07) << 18) | ((d & 0x3f) << 12) | ((p[-1] & 0x3f) << 6) | (*p & 0x3f);
1.1 misho 219: break;
220:
1.1.1.2 ! misho 221: /* 5-byte and 6-byte characters are not allowed by RFC 3629, and will be
! 222: rejected by the length test below. However, we do the appropriate tests
! 223: here so that overlong sequences get diagnosed, and also in case there is
! 224: ever an option for handling these larger code points. */
! 225:
! 226: /* 5-byte character. Check 3rd, 4th, and 5th bytes for 0x80. Then check for
! 227: 1111 1000, xx00 0xxx */
1.1 misho 228:
229: case 4:
1.1.1.2 ! misho 230: if ((*(++p) & 0xc0) != 0x80) /* Third byte */
! 231: {
! 232: *erroroffset = (int)(p - string) - 2;
! 233: return PCRE_UTF8_ERR7;
! 234: }
! 235: if ((*(++p) & 0xc0) != 0x80) /* Fourth byte */
! 236: {
! 237: *erroroffset = (int)(p - string) - 3;
! 238: return PCRE_UTF8_ERR8;
! 239: }
! 240: if ((*(++p) & 0xc0) != 0x80) /* Fifth byte */
! 241: {
! 242: *erroroffset = (int)(p - string) - 4;
! 243: return PCRE_UTF8_ERR9;
! 244: }
! 245: if (c == 0xf8 && (d & 0x38) == 0)
! 246: {
! 247: *erroroffset = (int)(p - string) - 4;
! 248: return PCRE_UTF8_ERR18;
! 249: }
1.1 misho 250: break;
251:
1.1.1.2 ! misho 252: /* 6-byte character. Check 3rd-6th bytes for 0x80. Then check for
! 253: 1111 1100, xx00 00xx. */
! 254:
1.1 misho 255: case 5:
1.1.1.2 ! misho 256: if ((*(++p) & 0xc0) != 0x80) /* Third byte */
! 257: {
! 258: *erroroffset = (int)(p - string) - 2;
! 259: return PCRE_UTF8_ERR7;
! 260: }
! 261: if ((*(++p) & 0xc0) != 0x80) /* Fourth byte */
! 262: {
! 263: *erroroffset = (int)(p - string) - 3;
! 264: return PCRE_UTF8_ERR8;
! 265: }
! 266: if ((*(++p) & 0xc0) != 0x80) /* Fifth byte */
! 267: {
! 268: *erroroffset = (int)(p - string) - 4;
! 269: return PCRE_UTF8_ERR9;
! 270: }
! 271: if ((*(++p) & 0xc0) != 0x80) /* Sixth byte */
! 272: {
! 273: *erroroffset = (int)(p - string) - 5;
! 274: return PCRE_UTF8_ERR10;
! 275: }
! 276: if (c == 0xfc && (d & 0x3c) == 0)
! 277: {
! 278: *erroroffset = (int)(p - string) - 5;
! 279: return PCRE_UTF8_ERR19;
! 280: }
1.1 misho 281: break;
1.1.1.2 ! misho 282: }
1.1 misho 283:
1.1.1.2 ! misho 284: /* Character is valid under RFC 2279, but 4-byte and 5-byte characters are
! 285: excluded by RFC 3629. The pointer p is currently at the last byte of the
! 286: character. */
! 287:
! 288: if (ab > 3)
! 289: {
! 290: *erroroffset = (int)(p - string) - ab;
! 291: return (ab == 4)? PCRE_UTF8_ERR11 : PCRE_UTF8_ERR12;
1.1 misho 292: }
293:
1.1.1.2 ! misho 294: /* Reject non-characters. The pointer p is currently at the last byte of the
! 295: character. */
! 296: if ((v & 0xfffeu) == 0xfffeu || (v >= 0xfdd0 && v <= 0xfdef))
1.1 misho 297: {
1.1.1.2 ! misho 298: *erroroffset = (int)(p - string) - ab;
! 299: return PCRE_UTF8_ERR22;
1.1 misho 300: }
301: }
1.1.1.2 ! misho 302:
! 303: #else /* Not SUPPORT_UTF */
1.1 misho 304: (void)(string); /* Keep picky compilers happy */
305: (void)(length);
1.1.1.2 ! misho 306: (void)(erroroffset);
1.1 misho 307: #endif
308:
1.1.1.2 ! misho 309: return PCRE_UTF8_ERR0; /* This indicates success */
1.1 misho 310: }
311:
312: /* End of pcre_valid_utf8.c */
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>
![[BACK]](/icons/cvsweb/back.gif){kind=icon}
Return to pcre_valid_utf8.c CVS log ![[TXT]](/icons/cvsweb/text.gif){kind=icon}
![[DIR]](/icons/cvsweb/dir.gif){kind=icon}
Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / php / ext / pcre / pcrelib