388 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
		
		
			
		
	
	
			388 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
|  | <?php | ||
|  | 
 | ||
|  | /** | ||
|  |  * IDNA URL encoder | ||
|  |  * | ||
|  |  * Note: Not fully compliant, as nameprep does nothing yet. | ||
|  |  * | ||
|  |  * @package Requests | ||
|  |  * @subpackage Utilities | ||
|  |  * @see https://tools.ietf.org/html/rfc3490 IDNA specification | ||
|  |  * @see https://tools.ietf.org/html/rfc3492 Punycode/Bootstrap specification | ||
|  |  */ | ||
|  | class Requests_IDNAEncoder { | ||
|  | 	/** | ||
|  | 	 * ACE prefix used for IDNA | ||
|  | 	 * | ||
|  | 	 * @see https://tools.ietf.org/html/rfc3490#section-5
 | ||
|  | 	 * @var string | ||
|  | 	 */ | ||
|  | 	const ACE_PREFIX = 'xn--'; | ||
|  | 
 | ||
|  | 	/**#@+
 | ||
|  | 	 * Bootstrap constant for Punycode | ||
|  | 	 * | ||
|  | 	 * @see https://tools.ietf.org/html/rfc3492#section-5
 | ||
|  | 	 * @var int | ||
|  | 	 */ | ||
|  | 	const BOOTSTRAP_BASE         = 36; | ||
|  | 	const BOOTSTRAP_TMIN         = 1; | ||
|  | 	const BOOTSTRAP_TMAX         = 26; | ||
|  | 	const BOOTSTRAP_SKEW         = 38; | ||
|  | 	const BOOTSTRAP_DAMP         = 700; | ||
|  | 	const BOOTSTRAP_INITIAL_BIAS = 72; | ||
|  | 	const BOOTSTRAP_INITIAL_N    = 128; | ||
|  | 	/**#@-*/ | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Encode a hostname using Punycode | ||
|  | 	 * | ||
|  | 	 * @param string $string Hostname | ||
|  | 	 * @return string Punycode-encoded hostname | ||
|  | 	 */ | ||
|  | 	public static function encode($string) { | ||
|  | 		$parts = explode('.', $string); | ||
|  | 		foreach ($parts as &$part) { | ||
|  | 			$part = self::to_ascii($part); | ||
|  | 		} | ||
|  | 		return implode('.', $parts); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Convert a UTF-8 string to an ASCII string using Punycode | ||
|  | 	 * | ||
|  | 	 * @throws Requests_Exception Provided string longer than 64 ASCII characters (`idna.provided_too_long`) | ||
|  | 	 * @throws Requests_Exception Prepared string longer than 64 ASCII characters (`idna.prepared_too_long`) | ||
|  | 	 * @throws Requests_Exception Provided string already begins with xn-- (`idna.provided_is_prefixed`) | ||
|  | 	 * @throws Requests_Exception Encoded string longer than 64 ASCII characters (`idna.encoded_too_long`) | ||
|  | 	 * | ||
|  | 	 * @param string $string ASCII or UTF-8 string (max length 64 characters) | ||
|  | 	 * @return string ASCII string | ||
|  | 	 */ | ||
|  | 	public static function to_ascii($string) { | ||
|  | 		// Step 1: Check if the string is already ASCII
 | ||
|  | 		if (self::is_ascii($string)) { | ||
|  | 			// Skip to step 7
 | ||
|  | 			if (strlen($string) < 64) { | ||
|  | 				return $string; | ||
|  | 			} | ||
|  | 
 | ||
|  | 			throw new Requests_Exception('Provided string is too long', 'idna.provided_too_long', $string); | ||
|  | 		} | ||
|  | 
 | ||
|  | 		// Step 2: nameprep
 | ||
|  | 		$string = self::nameprep($string); | ||
|  | 
 | ||
|  | 		// Step 3: UseSTD3ASCIIRules is false, continue
 | ||
|  | 		// Step 4: Check if it's ASCII now
 | ||
|  | 		if (self::is_ascii($string)) { | ||
|  | 			// Skip to step 7
 | ||
|  | 			if (strlen($string) < 64) { | ||
|  | 				return $string; | ||
|  | 			} | ||
|  | 
 | ||
|  | 			throw new Requests_Exception('Prepared string is too long', 'idna.prepared_too_long', $string); | ||
|  | 		} | ||
|  | 
 | ||
|  | 		// Step 5: Check ACE prefix
 | ||
|  | 		if (strpos($string, self::ACE_PREFIX) === 0) { | ||
|  | 			throw new Requests_Exception('Provided string begins with ACE prefix', 'idna.provided_is_prefixed', $string); | ||
|  | 		} | ||
|  | 
 | ||
|  | 		// Step 6: Encode with Punycode
 | ||
|  | 		$string = self::punycode_encode($string); | ||
|  | 
 | ||
|  | 		// Step 7: Prepend ACE prefix
 | ||
|  | 		$string = self::ACE_PREFIX . $string; | ||
|  | 
 | ||
|  | 		// Step 8: Check size
 | ||
|  | 		if (strlen($string) < 64) { | ||
|  | 			return $string; | ||
|  | 		} | ||
|  | 
 | ||
|  | 		throw new Requests_Exception('Encoded string is too long', 'idna.encoded_too_long', $string); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Check whether a given string contains only ASCII characters | ||
|  | 	 * | ||
|  | 	 * @internal (Testing found regex was the fastest implementation) | ||
|  | 	 * | ||
|  | 	 * @param string $string | ||
|  | 	 * @return bool Is the string ASCII-only? | ||
|  | 	 */ | ||
|  | 	protected static function is_ascii($string) { | ||
|  | 		return (preg_match('/(?:[^\x00-\x7F])/', $string) !== 1); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Prepare a string for use as an IDNA name | ||
|  | 	 * | ||
|  | 	 * @todo Implement this based on RFC 3491 and the newer 5891 | ||
|  | 	 * @param string $string | ||
|  | 	 * @return string Prepared string | ||
|  | 	 */ | ||
|  | 	protected static function nameprep($string) { | ||
|  | 		return $string; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Convert a UTF-8 string to a UCS-4 codepoint array | ||
|  | 	 * | ||
|  | 	 * Based on Requests_IRI::replace_invalid_with_pct_encoding() | ||
|  | 	 * | ||
|  | 	 * @throws Requests_Exception Invalid UTF-8 codepoint (`idna.invalidcodepoint`) | ||
|  | 	 * @param string $input | ||
|  | 	 * @return array Unicode code points | ||
|  | 	 */ | ||
|  | 	protected static function utf8_to_codepoints($input) { | ||
|  | 		$codepoints = array(); | ||
|  | 
 | ||
|  | 		// Get number of bytes
 | ||
|  | 		$strlen = strlen($input); | ||
|  | 
 | ||
|  | 		for ($position = 0; $position < $strlen; $position++) { | ||
|  | 			$value = ord($input[$position]); | ||
|  | 
 | ||
|  | 			// One byte sequence:
 | ||
|  | 			if ((~$value & 0x80) === 0x80) { | ||
|  | 				$character = $value; | ||
|  | 				$length = 1; | ||
|  | 				$remaining = 0; | ||
|  | 			} | ||
|  | 			// Two byte sequence:
 | ||
|  | 			elseif (($value & 0xE0) === 0xC0) { | ||
|  | 				$character = ($value & 0x1F) << 6; | ||
|  | 				$length = 2; | ||
|  | 				$remaining = 1; | ||
|  | 			} | ||
|  | 			// Three byte sequence:
 | ||
|  | 			elseif (($value & 0xF0) === 0xE0) { | ||
|  | 				$character = ($value & 0x0F) << 12; | ||
|  | 				$length = 3; | ||
|  | 				$remaining = 2; | ||
|  | 			} | ||
|  | 			// Four byte sequence:
 | ||
|  | 			elseif (($value & 0xF8) === 0xF0) { | ||
|  | 				$character = ($value & 0x07) << 18; | ||
|  | 				$length = 4; | ||
|  | 				$remaining = 3; | ||
|  | 			} | ||
|  | 			// Invalid byte:
 | ||
|  | 			else { | ||
|  | 				throw new Requests_Exception('Invalid Unicode codepoint', 'idna.invalidcodepoint', $value); | ||
|  | 			} | ||
|  | 
 | ||
|  | 			if ($remaining > 0) { | ||
|  | 				if ($position + $length > $strlen) { | ||
|  | 					throw new Requests_Exception('Invalid Unicode codepoint', 'idna.invalidcodepoint', $character); | ||
|  | 				} | ||
|  | 				for ($position++; $remaining > 0; $position++) { | ||
|  | 					$value = ord($input[$position]); | ||
|  | 
 | ||
|  | 					// If it is invalid, count the sequence as invalid and reprocess the current byte:
 | ||
|  | 					if (($value & 0xC0) !== 0x80) { | ||
|  | 						throw new Requests_Exception('Invalid Unicode codepoint', 'idna.invalidcodepoint', $character); | ||
|  | 					} | ||
|  | 
 | ||
|  | 					$character |= ($value & 0x3F) << (--$remaining * 6); | ||
|  | 				} | ||
|  | 				$position--; | ||
|  | 			} | ||
|  | 
 | ||
|  | 			if ( | ||
|  | 				// Non-shortest form sequences are invalid
 | ||
|  | 				   $length > 1 && $character <= 0x7F | ||
|  | 				|| $length > 2 && $character <= 0x7FF | ||
|  | 				|| $length > 3 && $character <= 0xFFFF | ||
|  | 				// Outside of range of ucschar codepoints
 | ||
|  | 				// Noncharacters
 | ||
|  | 				|| ($character & 0xFFFE) === 0xFFFE | ||
|  | 				|| $character >= 0xFDD0 && $character <= 0xFDEF | ||
|  | 				|| ( | ||
|  | 					// Everything else not in ucschar
 | ||
|  | 					   $character > 0xD7FF && $character < 0xF900 | ||
|  | 					|| $character < 0x20 | ||
|  | 					|| $character > 0x7E && $character < 0xA0 | ||
|  | 					|| $character > 0xEFFFD | ||
|  | 				) | ||
|  | 			) { | ||
|  | 				throw new Requests_Exception('Invalid Unicode codepoint', 'idna.invalidcodepoint', $character); | ||
|  | 			} | ||
|  | 
 | ||
|  | 			$codepoints[] = $character; | ||
|  | 		} | ||
|  | 
 | ||
|  | 		return $codepoints; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * RFC3492-compliant encoder | ||
|  | 	 * | ||
|  | 	 * @internal Pseudo-code from Section 6.3 is commented with "#" next to relevant code | ||
|  | 	 * @throws Requests_Exception On character outside of the domain (never happens with Punycode) (`idna.character_outside_domain`) | ||
|  | 	 * | ||
|  | 	 * @param string $input UTF-8 encoded string to encode | ||
|  | 	 * @return string Punycode-encoded string | ||
|  | 	 */ | ||
|  | 	public static function punycode_encode($input) { | ||
|  | 		$output = ''; | ||
|  | #		let n = initial_n
 | ||
|  | 		$n = self::BOOTSTRAP_INITIAL_N; | ||
|  | #		let delta = 0
 | ||
|  | 		$delta = 0; | ||
|  | #		let bias = initial_bias
 | ||
|  | 		$bias = self::BOOTSTRAP_INITIAL_BIAS; | ||
|  | #		let h = b = the number of basic code points in the input
 | ||
|  | 		$h = $b = 0; // see loop
 | ||
|  | #		copy them to the output in order
 | ||
|  | 		$codepoints = self::utf8_to_codepoints($input); | ||
|  | 		$extended = array(); | ||
|  | 
 | ||
|  | 		foreach ($codepoints as $char) { | ||
|  | 			if ($char < 128) { | ||
|  | 				// Character is valid ASCII
 | ||
|  | 				// TODO: this should also check if it's valid for a URL
 | ||
|  | 				$output .= chr($char); | ||
|  | 				$h++; | ||
|  | 			} | ||
|  | 			// Check if the character is non-ASCII, but below initial n
 | ||
|  | 			// This never occurs for Punycode, so ignore in coverage
 | ||
|  | 			// @codeCoverageIgnoreStart
 | ||
|  | 			elseif ($char < $n) { | ||
|  | 				throw new Requests_Exception('Invalid character', 'idna.character_outside_domain', $char); | ||
|  | 			} | ||
|  | 			// @codeCoverageIgnoreEnd
 | ||
|  | 			else { | ||
|  | 				$extended[$char] = true; | ||
|  | 			} | ||
|  | 		} | ||
|  | 		$extended = array_keys($extended); | ||
|  | 		sort($extended); | ||
|  | 		$b = $h; | ||
|  | #		[copy them] followed by a delimiter if b > 0
 | ||
|  | 		if (strlen($output) > 0) { | ||
|  | 			$output .= '-'; | ||
|  | 		} | ||
|  | #		{if the input contains a non-basic code point < n then fail}
 | ||
|  | #		while h < length(input) do begin
 | ||
|  | 		while ($h < count($codepoints)) { | ||
|  | #			let m = the minimum code point >= n in the input
 | ||
|  | 			$m = array_shift($extended); | ||
|  | 			//printf('next code point to insert is %s' . PHP_EOL, dechex($m));
 | ||
|  | #			let delta = delta + (m - n) * (h + 1), fail on overflow
 | ||
|  | 			$delta += ($m - $n) * ($h + 1); | ||
|  | #			let n = m
 | ||
|  | 			$n = $m; | ||
|  | #			for each code point c in the input (in order) do begin
 | ||
|  | 			for ($num = 0; $num < count($codepoints); $num++) { | ||
|  | 				$c = $codepoints[$num]; | ||
|  | #				if c < n then increment delta, fail on overflow
 | ||
|  | 				if ($c < $n) { | ||
|  | 					$delta++; | ||
|  | 				} | ||
|  | #				if c == n then begin
 | ||
|  | 				elseif ($c === $n) { | ||
|  | #					let q = delta
 | ||
|  | 					$q = $delta; | ||
|  | #					for k = base to infinity in steps of base do begin
 | ||
|  | 					for ($k = self::BOOTSTRAP_BASE; ; $k += self::BOOTSTRAP_BASE) { | ||
|  | #						let t = tmin if k <= bias {+ tmin}, or
 | ||
|  | #								tmax if k >= bias + tmax, or k - bias otherwise
 | ||
|  | 						if ($k <= ($bias + self::BOOTSTRAP_TMIN)) { | ||
|  | 							$t = self::BOOTSTRAP_TMIN; | ||
|  | 						} | ||
|  | 						elseif ($k >= ($bias + self::BOOTSTRAP_TMAX)) { | ||
|  | 							$t = self::BOOTSTRAP_TMAX; | ||
|  | 						} | ||
|  | 						else { | ||
|  | 							$t = $k - $bias; | ||
|  | 						} | ||
|  | #						if q < t then break
 | ||
|  | 						if ($q < $t) { | ||
|  | 							break; | ||
|  | 						} | ||
|  | #						output the code point for digit t + ((q - t) mod (base - t))
 | ||
|  | 						$digit = $t + (($q - $t) % (self::BOOTSTRAP_BASE - $t)); | ||
|  | 						$output .= self::digit_to_char($digit); | ||
|  | #						let q = (q - t) div (base - t)
 | ||
|  | 						$q = floor(($q - $t) / (self::BOOTSTRAP_BASE - $t)); | ||
|  | #					end
 | ||
|  | 					} | ||
|  | #					output the code point for digit q
 | ||
|  | 					$output .= self::digit_to_char($q); | ||
|  | #					let bias = adapt(delta, h + 1, test h equals b?)
 | ||
|  | 					$bias = self::adapt($delta, $h + 1, $h === $b); | ||
|  | #					let delta = 0
 | ||
|  | 					$delta = 0; | ||
|  | #					increment h
 | ||
|  | 					$h++; | ||
|  | #				end
 | ||
|  | 				} | ||
|  | #			end
 | ||
|  | 			} | ||
|  | #			increment delta and n
 | ||
|  | 			$delta++; | ||
|  | 			$n++; | ||
|  | #		end
 | ||
|  | 		} | ||
|  | 
 | ||
|  | 		return $output; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Convert a digit to its respective character | ||
|  | 	 * | ||
|  | 	 * @see https://tools.ietf.org/html/rfc3492#section-5
 | ||
|  | 	 * @throws Requests_Exception On invalid digit (`idna.invalid_digit`) | ||
|  | 	 * | ||
|  | 	 * @param int $digit Digit in the range 0-35 | ||
|  | 	 * @return string Single character corresponding to digit | ||
|  | 	 */ | ||
|  | 	protected static function digit_to_char($digit) { | ||
|  | 		// @codeCoverageIgnoreStart
 | ||
|  | 		// As far as I know, this never happens, but still good to be sure.
 | ||
|  | 		if ($digit < 0 || $digit > 35) { | ||
|  | 			throw new Requests_Exception(sprintf('Invalid digit %d', $digit), 'idna.invalid_digit', $digit); | ||
|  | 		} | ||
|  | 		// @codeCoverageIgnoreEnd
 | ||
|  | 		$digits = 'abcdefghijklmnopqrstuvwxyz0123456789'; | ||
|  | 		return substr($digits, $digit, 1); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/** | ||
|  | 	 * Adapt the bias | ||
|  | 	 * | ||
|  | 	 * @see https://tools.ietf.org/html/rfc3492#section-6.1
 | ||
|  | 	 * @param int $delta | ||
|  | 	 * @param int $numpoints | ||
|  | 	 * @param bool $firsttime | ||
|  | 	 * @return int New bias | ||
|  | 	 */ | ||
|  | 	protected static function adapt($delta, $numpoints, $firsttime) { | ||
|  | #	function adapt(delta,numpoints,firsttime):
 | ||
|  | #		if firsttime then let delta = delta div damp
 | ||
|  | 		if ($firsttime) { | ||
|  | 			$delta = floor($delta / self::BOOTSTRAP_DAMP); | ||
|  | 		} | ||
|  | #		else let delta = delta div 2
 | ||
|  | 		else { | ||
|  | 			$delta = floor($delta / 2); | ||
|  | 		} | ||
|  | #		let delta = delta + (delta div numpoints)
 | ||
|  | 		$delta += floor($delta / $numpoints); | ||
|  | #		let k = 0
 | ||
|  | 		$k = 0; | ||
|  | #		while delta > ((base - tmin) * tmax) div 2 do begin
 | ||
|  | 		$max = floor(((self::BOOTSTRAP_BASE - self::BOOTSTRAP_TMIN) * self::BOOTSTRAP_TMAX) / 2); | ||
|  | 		while ($delta > $max) { | ||
|  | #			let delta = delta div (base - tmin)
 | ||
|  | 			$delta = floor($delta / (self::BOOTSTRAP_BASE - self::BOOTSTRAP_TMIN)); | ||
|  | #			let k = k + base
 | ||
|  | 			$k += self::BOOTSTRAP_BASE; | ||
|  | #		end
 | ||
|  | 		} | ||
|  | #		return k + (((base - tmin + 1) * delta) div (delta + skew))
 | ||
|  | 		return $k + floor(((self::BOOTSTRAP_BASE - self::BOOTSTRAP_TMIN + 1) * $delta) / ($delta + self::BOOTSTRAP_SKEW)); | ||
|  | 	} | ||
|  | } |