399 lines
		
	
	
		
			13 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			399 lines
		
	
	
		
			13 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|  | /*************************************************
 | ||
|  | *      Perl-Compatible Regular Expressions       * | ||
|  | *************************************************/ | ||
|  | 
 | ||
|  | /* PCRE is a library of functions to support regular expressions whose syntax
 | ||
|  | and semantics are as close as possible to those of the Perl 5 language. | ||
|  | 
 | ||
|  |                        Written by Philip Hazel | ||
|  |      Original API code Copyright (c) 1997-2012 University of Cambridge | ||
|  |           New API code Copyright (c) 2016-2020 University of Cambridge | ||
|  | 
 | ||
|  | ----------------------------------------------------------------------------- | ||
|  | Redistribution and use in source and binary forms, with or without | ||
|  | modification, are permitted provided that the following conditions are met: | ||
|  | 
 | ||
|  |     * Redistributions of source code must retain the above copyright notice, | ||
|  |       this list of conditions and the following disclaimer. | ||
|  | 
 | ||
|  |     * Redistributions in binary form must reproduce the above copyright | ||
|  |       notice, this list of conditions and the following disclaimer in the | ||
|  |       documentation and/or other materials provided with the distribution. | ||
|  | 
 | ||
|  |     * Neither the name of the University of Cambridge nor the names of its | ||
|  |       contributors may be used to endorse or promote products derived from | ||
|  |       this software without specific prior written permission. | ||
|  | 
 | ||
|  | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | ||
|  | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
|  | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
|  | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | ||
|  | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | ||
|  | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | ||
|  | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | ||
|  | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | ||
|  | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
|  | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | ||
|  | POSSIBILITY OF SUCH DAMAGE. | ||
|  | ----------------------------------------------------------------------------- | ||
|  | */ | ||
|  | 
 | ||
|  | 
 | ||
|  | /* This module contains an internal function for validating UTF character
 | ||
|  | strings. This file is also #included by the pcre2test program, which uses | ||
|  | macros to change names from _pcre2_xxx to xxxx, thereby avoiding name clashes | ||
|  | with the library. In this case, PCRE2_PCRE2TEST is defined. */ | ||
|  | 
 | ||
|  | #ifndef PCRE2_PCRE2TEST           /* We're compiling the library */
 | ||
|  | #ifdef HAVE_CONFIG_H
 | ||
|  | #include "config.h"
 | ||
|  | #endif
 | ||
|  | #include "pcre2_internal.h"
 | ||
|  | #endif /* PCRE2_PCRE2TEST */
 | ||
|  | 
 | ||
|  | 
 | ||
|  | #ifndef SUPPORT_UNICODE
 | ||
|  | /*************************************************
 | ||
|  | *  Dummy function when Unicode is not supported  * | ||
|  | *************************************************/ | ||
|  | 
 | ||
|  | /* This function should never be called when Unicode is not supported. */ | ||
|  | 
 | ||
|  | int | ||
|  | PRIV(valid_utf)(PCRE2_SPTR string, PCRE2_SIZE length, PCRE2_SIZE *erroroffset) | ||
|  | { | ||
|  | (void)string; | ||
|  | (void)length; | ||
|  | (void)erroroffset; | ||
|  | return 0; | ||
|  | } | ||
|  | #else  /* UTF is supported */
 | ||
|  | 
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /*************************************************
 | ||
|  | *           Validate a UTF string                * | ||
|  | *************************************************/ | ||
|  | 
 | ||
|  | /* This function is called (optionally) at the start of compile or match, to
 | ||
|  | check that a supposed UTF string is actually valid. The early check means | ||
|  | that subsequent code can assume it is dealing with a valid string. The check | ||
|  | can be turned off for maximum performance, but the consequences of supplying an | ||
|  | invalid string are then undefined. | ||
|  | 
 | ||
|  | Arguments: | ||
|  |   string       points to the string | ||
|  |   length       length of string | ||
|  |   errp         pointer to an error position offset variable | ||
|  | 
 | ||
|  | Returns:       == 0    if the string is a valid UTF string | ||
|  |                != 0    otherwise, setting the offset of the bad character | ||
|  | */ | ||
|  | 
 | ||
|  | int | ||
|  | PRIV(valid_utf)(PCRE2_SPTR string, PCRE2_SIZE length, PCRE2_SIZE *erroroffset) | ||
|  | { | ||
|  | PCRE2_SPTR p; | ||
|  | uint32_t c; | ||
|  | 
 | ||
|  | /* ----------------- Check a UTF-8 string ----------------- */ | ||
|  | 
 | ||
|  | #if PCRE2_CODE_UNIT_WIDTH == 8
 | ||
|  | 
 | ||
|  | /* Originally, this function checked according to RFC 2279, allowing for values
 | ||
|  | in the range 0 to 0x7fffffff, up to 6 bytes long, but ensuring that they were | ||
|  | in the canonical format. Once somebody had pointed out RFC 3629 to me (it | ||
|  | obsoletes 2279), additional restrictions were applied. The values are now | ||
|  | limited to be between 0 and 0x0010ffff, no more than 4 bytes long, and the | ||
|  | subrange 0xd000 to 0xdfff is excluded. However, the format of 5-byte and 6-byte | ||
|  | characters is still checked. Error returns are as follows: | ||
|  | 
 | ||
|  | PCRE2_ERROR_UTF8_ERR1   Missing 1 byte at the end of the string | ||
|  | PCRE2_ERROR_UTF8_ERR2   Missing 2 bytes at the end of the string | ||
|  | PCRE2_ERROR_UTF8_ERR3   Missing 3 bytes at the end of the string | ||
|  | PCRE2_ERROR_UTF8_ERR4   Missing 4 bytes at the end of the string | ||
|  | PCRE2_ERROR_UTF8_ERR5   Missing 5 bytes at the end of the string | ||
|  | PCRE2_ERROR_UTF8_ERR6   2nd-byte's two top bits are not 0x80 | ||
|  | PCRE2_ERROR_UTF8_ERR7   3rd-byte's two top bits are not 0x80 | ||
|  | PCRE2_ERROR_UTF8_ERR8   4th-byte's two top bits are not 0x80 | ||
|  | PCRE2_ERROR_UTF8_ERR9   5th-byte's two top bits are not 0x80 | ||
|  | PCRE2_ERROR_UTF8_ERR10  6th-byte's two top bits are not 0x80 | ||
|  | PCRE2_ERROR_UTF8_ERR11  5-byte character is not permitted by RFC 3629 | ||
|  | PCRE2_ERROR_UTF8_ERR12  6-byte character is not permitted by RFC 3629 | ||
|  | PCRE2_ERROR_UTF8_ERR13  4-byte character with value > 0x10ffff is not permitted | ||
|  | PCRE2_ERROR_UTF8_ERR14  3-byte character with value 0xd800-0xdfff is not permitted | ||
|  | PCRE2_ERROR_UTF8_ERR15  Overlong 2-byte sequence | ||
|  | PCRE2_ERROR_UTF8_ERR16  Overlong 3-byte sequence | ||
|  | PCRE2_ERROR_UTF8_ERR17  Overlong 4-byte sequence | ||
|  | PCRE2_ERROR_UTF8_ERR18  Overlong 5-byte sequence (won't ever occur) | ||
|  | PCRE2_ERROR_UTF8_ERR19  Overlong 6-byte sequence (won't ever occur) | ||
|  | PCRE2_ERROR_UTF8_ERR20  Isolated 0x80 byte (not within UTF-8 character) | ||
|  | PCRE2_ERROR_UTF8_ERR21  Byte with the illegal value 0xfe or 0xff | ||
|  | */ | ||
|  | 
 | ||
|  | for (p = string; length > 0; p++) | ||
|  |   { | ||
|  |   uint32_t ab, d; | ||
|  | 
 | ||
|  |   c = *p; | ||
|  |   length--; | ||
|  | 
 | ||
|  |   if (c < 128) continue;                /* ASCII character */ | ||
|  | 
 | ||
|  |   if (c < 0xc0)                         /* Isolated 10xx xxxx byte */ | ||
|  |     { | ||
|  |     *erroroffset = (PCRE2_SIZE)(p - string); | ||
|  |     return PCRE2_ERROR_UTF8_ERR20; | ||
|  |     } | ||
|  | 
 | ||
|  |   if (c >= 0xfe)                        /* Invalid 0xfe or 0xff bytes */ | ||
|  |     { | ||
|  |     *erroroffset = (PCRE2_SIZE)(p - string); | ||
|  |     return PCRE2_ERROR_UTF8_ERR21; | ||
|  |     } | ||
|  | 
 | ||
|  |   ab = PRIV(utf8_table4)[c & 0x3f];     /* Number of additional bytes (1-5) */ | ||
|  |   if (length < ab)                      /* Missing bytes */ | ||
|  |     { | ||
|  |     *erroroffset = (PCRE2_SIZE)(p - string); | ||
|  |     switch(ab - length) | ||
|  |       { | ||
|  |       case 1: return PCRE2_ERROR_UTF8_ERR1; | ||
|  |       case 2: return PCRE2_ERROR_UTF8_ERR2; | ||
|  |       case 3: return PCRE2_ERROR_UTF8_ERR3; | ||
|  |       case 4: return PCRE2_ERROR_UTF8_ERR4; | ||
|  |       case 5: return PCRE2_ERROR_UTF8_ERR5; | ||
|  |       } | ||
|  |     } | ||
|  |   length -= ab;                         /* Length remaining */ | ||
|  | 
 | ||
|  |   /* Check top bits in the second byte */ | ||
|  | 
 | ||
|  |   if (((d = *(++p)) & 0xc0) != 0x80) | ||
|  |     { | ||
|  |     *erroroffset = (int)(p - string) - 1; | ||
|  |     return PCRE2_ERROR_UTF8_ERR6; | ||
|  |     } | ||
|  | 
 | ||
|  |   /* For each length, check that the remaining bytes start with the 0x80 bit
 | ||
|  |   set and not the 0x40 bit. Then check for an overlong sequence, and for the | ||
|  |   excluded range 0xd800 to 0xdfff. */ | ||
|  | 
 | ||
|  |   switch (ab) | ||
|  |     { | ||
|  |     /* 2-byte character. No further bytes to check for 0x80. Check first byte
 | ||
|  |     for for xx00 000x (overlong sequence). */ | ||
|  | 
 | ||
|  |     case 1: if ((c & 0x3e) == 0) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 1; | ||
|  |       return PCRE2_ERROR_UTF8_ERR15; | ||
|  |       } | ||
|  |     break; | ||
|  | 
 | ||
|  |     /* 3-byte character. Check third byte for 0x80. Then check first 2 bytes
 | ||
|  |       for 1110 0000, xx0x xxxx (overlong sequence) or | ||
|  |           1110 1101, 1010 xxxx (0xd800 - 0xdfff) */ | ||
|  | 
 | ||
|  |     case 2: | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Third byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 2; | ||
|  |       return PCRE2_ERROR_UTF8_ERR7; | ||
|  |       } | ||
|  |     if (c == 0xe0 && (d & 0x20) == 0) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 2; | ||
|  |       return PCRE2_ERROR_UTF8_ERR16; | ||
|  |       } | ||
|  |     if (c == 0xed && d >= 0xa0) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 2; | ||
|  |       return PCRE2_ERROR_UTF8_ERR14; | ||
|  |       } | ||
|  |     break; | ||
|  | 
 | ||
|  |     /* 4-byte character. Check 3rd and 4th bytes for 0x80. Then check first 2
 | ||
|  |        bytes for for 1111 0000, xx00 xxxx (overlong sequence), then check for a | ||
|  |        character greater than 0x0010ffff (f4 8f bf bf) */ | ||
|  | 
 | ||
|  |     case 3: | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Third byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 2; | ||
|  |       return PCRE2_ERROR_UTF8_ERR7; | ||
|  |       } | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Fourth byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 3; | ||
|  |       return PCRE2_ERROR_UTF8_ERR8; | ||
|  |       } | ||
|  |     if (c == 0xf0 && (d & 0x30) == 0) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 3; | ||
|  |       return PCRE2_ERROR_UTF8_ERR17; | ||
|  |       } | ||
|  |     if (c > 0xf4 || (c == 0xf4 && d > 0x8f)) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 3; | ||
|  |       return PCRE2_ERROR_UTF8_ERR13; | ||
|  |       } | ||
|  |     break; | ||
|  | 
 | ||
|  |     /* 5-byte and 6-byte characters are not allowed by RFC 3629, and will be
 | ||
|  |     rejected by the length test below. However, we do the appropriate tests | ||
|  |     here so that overlong sequences get diagnosed, and also in case there is | ||
|  |     ever an option for handling these larger code points. */ | ||
|  | 
 | ||
|  |     /* 5-byte character. Check 3rd, 4th, and 5th bytes for 0x80. Then check for
 | ||
|  |     1111 1000, xx00 0xxx */ | ||
|  | 
 | ||
|  |     case 4: | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Third byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 2; | ||
|  |       return PCRE2_ERROR_UTF8_ERR7; | ||
|  |       } | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Fourth byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 3; | ||
|  |       return PCRE2_ERROR_UTF8_ERR8; | ||
|  |       } | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Fifth byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 4; | ||
|  |       return PCRE2_ERROR_UTF8_ERR9; | ||
|  |       } | ||
|  |     if (c == 0xf8 && (d & 0x38) == 0) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 4; | ||
|  |       return PCRE2_ERROR_UTF8_ERR18; | ||
|  |       } | ||
|  |     break; | ||
|  | 
 | ||
|  |     /* 6-byte character. Check 3rd-6th bytes for 0x80. Then check for
 | ||
|  |     1111 1100, xx00 00xx. */ | ||
|  | 
 | ||
|  |     case 5: | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Third byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 2; | ||
|  |       return PCRE2_ERROR_UTF8_ERR7; | ||
|  |       } | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Fourth byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 3; | ||
|  |       return PCRE2_ERROR_UTF8_ERR8; | ||
|  |       } | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Fifth byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 4; | ||
|  |       return PCRE2_ERROR_UTF8_ERR9; | ||
|  |       } | ||
|  |     if ((*(++p) & 0xc0) != 0x80)     /* Sixth byte */ | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 5; | ||
|  |       return PCRE2_ERROR_UTF8_ERR10; | ||
|  |       } | ||
|  |     if (c == 0xfc && (d & 0x3c) == 0) | ||
|  |       { | ||
|  |       *erroroffset = (int)(p - string) - 5; | ||
|  |       return PCRE2_ERROR_UTF8_ERR19; | ||
|  |       } | ||
|  |     break; | ||
|  |     } | ||
|  | 
 | ||
|  |   /* Character is valid under RFC 2279, but 4-byte and 5-byte characters are
 | ||
|  |   excluded by RFC 3629. The pointer p is currently at the last byte of the | ||
|  |   character. */ | ||
|  | 
 | ||
|  |   if (ab > 3) | ||
|  |     { | ||
|  |     *erroroffset = (int)(p - string) - ab; | ||
|  |     return (ab == 4)? PCRE2_ERROR_UTF8_ERR11 : PCRE2_ERROR_UTF8_ERR12; | ||
|  |     } | ||
|  |   } | ||
|  | return 0; | ||
|  | 
 | ||
|  | 
 | ||
|  | /* ----------------- Check a UTF-16 string ----------------- */ | ||
|  | 
 | ||
|  | #elif PCRE2_CODE_UNIT_WIDTH == 16
 | ||
|  | 
 | ||
|  | /* There's not so much work, nor so many errors, for UTF-16.
 | ||
|  | PCRE2_ERROR_UTF16_ERR1  Missing low surrogate at the end of the string | ||
|  | PCRE2_ERROR_UTF16_ERR2  Invalid low surrogate | ||
|  | PCRE2_ERROR_UTF16_ERR3  Isolated low surrogate | ||
|  | */ | ||
|  | 
 | ||
|  | for (p = string; length > 0; p++) | ||
|  |   { | ||
|  |   c = *p; | ||
|  |   length--; | ||
|  | 
 | ||
|  |   if ((c & 0xf800) != 0xd800) | ||
|  |     { | ||
|  |     /* Normal UTF-16 code point. Neither high nor low surrogate. */ | ||
|  |     } | ||
|  |   else if ((c & 0x0400) == 0) | ||
|  |     { | ||
|  |     /* High surrogate. Must be a followed by a low surrogate. */ | ||
|  |     if (length == 0) | ||
|  |       { | ||
|  |       *erroroffset = p - string; | ||
|  |       return PCRE2_ERROR_UTF16_ERR1; | ||
|  |       } | ||
|  |     p++; | ||
|  |     length--; | ||
|  |     if ((*p & 0xfc00) != 0xdc00) | ||
|  |       { | ||
|  |       *erroroffset = p - string - 1; | ||
|  |       return PCRE2_ERROR_UTF16_ERR2; | ||
|  |       } | ||
|  |     } | ||
|  |   else | ||
|  |     { | ||
|  |     /* Isolated low surrogate. Always an error. */ | ||
|  |     *erroroffset = p - string; | ||
|  |     return PCRE2_ERROR_UTF16_ERR3; | ||
|  |     } | ||
|  |   } | ||
|  | return 0; | ||
|  | 
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /* ----------------- Check a UTF-32 string ----------------- */ | ||
|  | 
 | ||
|  | #else
 | ||
|  | 
 | ||
|  | /* There is very little to do for a UTF-32 string.
 | ||
|  | PCRE2_ERROR_UTF32_ERR1  Surrogate character | ||
|  | PCRE2_ERROR_UTF32_ERR2  Character > 0x10ffff | ||
|  | */ | ||
|  | 
 | ||
|  | for (p = string; length > 0; length--, p++) | ||
|  |   { | ||
|  |   c = *p; | ||
|  |   if ((c & 0xfffff800u) != 0xd800u) | ||
|  |     { | ||
|  |     /* Normal UTF-32 code point. Neither high nor low surrogate. */ | ||
|  |     if (c > 0x10ffffu) | ||
|  |       { | ||
|  |       *erroroffset = p - string; | ||
|  |       return PCRE2_ERROR_UTF32_ERR2; | ||
|  |       } | ||
|  |     } | ||
|  |   else | ||
|  |     { | ||
|  |     /* A surrogate */ | ||
|  |     *erroroffset = p - string; | ||
|  |     return PCRE2_ERROR_UTF32_ERR1; | ||
|  |     } | ||
|  |   } | ||
|  | return 0; | ||
|  | #endif  /* CODE_UNIT_WIDTH */
 | ||
|  | } | ||
|  | #endif  /* SUPPORT_UNICODE */
 | ||
|  | 
 | ||
|  | /* End of pcre2_valid_utf.c */ |