Explicitly check hex2bin input

For #23197

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>
This commit is contained in:
Roeland Jago Douma 2021-02-18 20:12:20 +01:00
parent 3c9b923eb1
commit 86de5d9265
1 changed files with 19 additions and 3 deletions

View File

@ -122,14 +122,14 @@ class Crypto implements ICrypto {
throw new \Exception('Authenticated ciphertext could not be decoded.');
}
$ciphertext = hex2bin($parts[0]);
$ciphertext = $this->hex2bin($parts[0]);
$iv = $parts[1];
$hmac = hex2bin($parts[2]);
$hmac = $this->hex2bin($parts[2]);
if ($partCount === 4) {
$version = $parts[3];
if ($version === '2') {
$iv = hex2bin($iv);
$iv = $this->hex2bin($iv);
}
}
@ -146,4 +146,20 @@ class Crypto implements ICrypto {
return $result;
}
private function hex2bin(string $hex): string {
if (!ctype_xdigit($hex)) {
throw new \RuntimeException('String contains non hex chars: ' . $hex);
}
if (strlen($hex) % 2 !== 0) {
throw new \RuntimeException('Hex string is not of even length: ' . $hex);
}
$result = hex2bin($hex);
if ($result === false) {
throw new \RuntimeException('Hex to bin conversion failed: ' . $hex);
}
return $result;
}
}