"Invalid SPKAC requests are not properly validated"
This commit is contained in:
Wytze van der Raay
parent
9bde006b4d
commit
316ef65915
5 changed files with 410 additions and 359 deletions
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@ -17,6 +17,7 @@
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*/
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*/
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require_once("../includes/loggedin.php");
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require_once("../includes/loggedin.php");
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require_once("../includes/lib/l10n.php");
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require_once("../includes/lib/l10n.php");
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require_once('lib/check_weak_key.php');
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loadem("account");
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loadem("account");
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@ -284,361 +284,3 @@ function hideall() {
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</body>
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</body>
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</html><?
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</html><?
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}
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}
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/**
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* Produces a log entry with the error message with log level E_USER_WARN
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* and a random ID an returns a message that can be displayed to the user
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* including the generated ID
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*
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* @param $errormessage string
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* The error message that should be logged
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* @return string containing the generated ID that can be displayed to the
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* user
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*/
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function failWithId($errormessage) {
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$errorId = rand();
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trigger_error("$errormessage. ID: $errorId", E_USER_WARNING);
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return sprintf(_("Something went wrong when processing your request. ".
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"Please contact %s for help and provide them with the ".
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"following ID: %d"),
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"<a href='mailto:support@cacert.org?subject=System%20Error%20-%20".
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"ID%3A%20$errorId'>support@cacert.org</a>",
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$errorId);
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}
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/**
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* Checks whether the given CSR contains a vulnerable key
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*
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* @param $csr string
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* The CSR to be checked
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* @param $encoding string [optional]
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* The encoding the CSR is in (for the "-inform" parameter of OpenSSL,
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* currently only "PEM" (default) or "DER" allowed)
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* @return string containing the reason if the key is considered weak,
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* empty string otherwise
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*/
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function checkWeakKeyCSR($csr, $encoding = "PEM")
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{
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// non-PEM-encodings may be binary so don't use echo
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$descriptorspec = array(
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0 => array("pipe", "r"), // STDIN for child
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1 => array("pipe", "w"), // STDOUT for child
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);
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$encoding = escapeshellarg($encoding);
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$proc = proc_open("openssl req -inform $encoding -text -noout",
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$descriptorspec, $pipes);
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if (is_resource($proc))
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{
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fwrite($pipes[0], $csr);
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fclose($pipes[0]);
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$csrText = "";
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while (!feof($pipes[1]))
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{
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$csrText .= fread($pipes[1], 8192);
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}
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fclose($pipes[1]);
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if (($status = proc_close($proc)) !== 0 || $csrText === "")
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{
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return _("I didn't receive a valid Certificate Request, hit ".
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"the back button and try again.");
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}
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} else {
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return failWithId("checkWeakKeyCSR(): Failed to start OpenSSL");
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}
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return checkWeakKeyText($csrText);
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}
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/**
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* Checks whether the given X509 certificate contains a vulnerable key
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*
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* @param $cert string
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* The X509 certificate to be checked
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* @param $encoding string [optional]
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* The encoding the certificate is in (for the "-inform" parameter of
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* OpenSSL, currently only "PEM" (default), "DER" or "NET" allowed)
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* @return string containing the reason if the key is considered weak,
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* empty string otherwise
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*/
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function checkWeakKeyX509($cert, $encoding = "PEM")
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{
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// non-PEM-encodings may be binary so don't use echo
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$descriptorspec = array(
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0 => array("pipe", "r"), // STDIN for child
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1 => array("pipe", "w"), // STDOUT for child
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);
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$encoding = escapeshellarg($encoding);
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$proc = proc_open("openssl x509 -inform $encoding -text -noout",
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$descriptorspec, $pipes);
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if (is_resource($proc))
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{
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fwrite($pipes[0], $cert);
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fclose($pipes[0]);
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$certText = "";
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while (!feof($pipes[1]))
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{
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$certText .= fread($pipes[1], 8192);
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}
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fclose($pipes[1]);
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if (($status = proc_close($proc)) !== 0 || $certText === "")
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{
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return _("I didn't receive a valid Certificate Request, hit ".
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"the back button and try again.");
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}
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} else {
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return failWithId("checkWeakKeyCSR(): Failed to start OpenSSL");
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}
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return checkWeakKeyText($certText);
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}
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/**
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* Checks whether the given SPKAC contains a vulnerable key
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*
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* @param $spkac string
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* The SPKAC to be checked
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* @param $spkacname string [optional]
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* The name of the variable that contains the SPKAC. The default is
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* "SPKAC"
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* @return string containing the reason if the key is considered weak,
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* empty string otherwise
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*/
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function checkWeakKeySPKAC($spkac, $spkacname = "SPKAC")
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{
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/* Check for the debian OpenSSL vulnerability */
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$spkac = escapeshellarg($spkac);
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$spkacname = escapeshellarg($spkacname);
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$spkacText = `echo $spkac | openssl spkac -spkac $spkacname`;
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if ($spkacText === null) {
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return _("I didn't receive a valid Certificate Request, hit the ".
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"back button and try again.");
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}
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return checkWeakKeyText($spkacText);
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}
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/**
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* Checks whether the given text representation of a CSR or a SPKAC contains
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* a weak key
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*
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* @param $text string
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* The text representation of a key as output by the
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* "openssl <foo> -text -noout" commands
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* @return string containing the reason if the key is considered weak,
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* empty string otherwise
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*/
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function checkWeakKeyText($text)
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{
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/* Which public key algorithm? */
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if (!preg_match('/^\s*Public Key Algorithm: ([^\s]+)$/m', $text,
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$algorithm))
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{
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return failWithId("checkWeakKeyText(): Couldn't extract the ".
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"public key algorithm used");
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} else {
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$algorithm = $algorithm[1];
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}
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if ($algorithm === "rsaEncryption")
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{
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if (!preg_match('/^\s*RSA Public Key: \((\d+) bit\)$/m', $text,
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$keysize))
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{
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return failWithId("checkWeakKeyText(): Couldn't parse the RSA ".
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"key size");
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} else {
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$keysize = intval($keysize[1]);
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}
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if ($keysize < 1024)
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{
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return sprintf(_("The keys that you use are very small ".
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"and therefore insecure. Please generate stronger ".
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"keys. More information about this issue can be ".
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"found in %sthe wiki%s"),
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"<a href='//wiki.cacert.org/WeakKeys#SmallKey'>",
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"</a>");
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} elseif ($keysize < 2048) {
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// not critical but log so we have some statistics about
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// affected users
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trigger_error("checkWeakKeyText(): Certificate for small ".
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"key (< 2048 bit) requested", E_USER_NOTICE);
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}
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$debianVuln = checkDebianVulnerability($text, $keysize);
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if ($debianVuln === true)
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{
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return sprintf(_("The keys you use have very likely been ".
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"generated with a vulnerable version of OpenSSL which ".
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"was distributed by debian. Please generate new keys. ".
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"More information about this issue can be found in ".
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"%sthe wiki%s"),
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"<a href='//wiki.cacert.org/WeakKeys#DebianVulnerability'>",
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"</a>");
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} elseif ($debianVuln === false) {
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// not vulnerable => do nothing
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} else {
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return failWithId("checkWeakKeyText(): Something went wrong in".
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"checkDebianVulnerability()");
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}
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if (!preg_match('/^\s*Exponent: (\d+) \(0x[0-9a-fA-F]+\)$/m', $text,
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$exponent))
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{
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return failWithId("checkWeakKeyText(): Couldn't parse the RSA ".
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"exponent");
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} else {
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$exponent = $exponent[1]; // exponent might be very big =>
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//handle as string using bc*()
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if (bccomp($exponent, "3") === 0)
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{
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return sprintf(_("The keys you use might be insecure. ".
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"Although there is currently no known attack for ".
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"reasonable encryption schemes, we're being ".
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"cautious and don't allow certificates for such ".
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"keys. Please generate stronger keys. More ".
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"information about this issue can be found in ".
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"%sthe wiki%s"),
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"<a href='//wiki.cacert.org/WeakKeys#SmallExponent'>",
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"</a>");
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} elseif (!(bccomp($exponent, "65537") >= 0 &&
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(bccomp($exponent, "100000") === -1 ||
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// speed things up if way smaller than 2^256
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bccomp($exponent, bcpow("2", "256")) === -1) )) {
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// 65537 <= exponent < 2^256 recommended by NIST
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// not critical but log so we have some statistics about
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// affected users
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trigger_error("checkWeakKeyText(): Certificate for ".
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"unsuitable exponent '$exponent' requested",
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E_USER_NOTICE);
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}
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}
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}
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/* No weakness found */
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return "";
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}
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/**
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* Reimplement the functionality of the openssl-vulnkey tool
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*
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* @param $text string
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* The text representation of a key as output by the
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* "openssl <foo> -text -noout" commands
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* @param $keysize int [optional]
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* If the key size is already known it can be provided so it doesn't
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* have to be parsed again. This also skips the check whether the key
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* is an RSA key => use wisely
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* @return TRUE if key is vulnerable, FALSE otherwise, NULL in case of error
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*/
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function checkDebianVulnerability($text, $keysize = 0)
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{
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$keysize = intval($keysize);
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if ($keysize === 0)
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{
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/* Which public key algorithm? */
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if (!preg_match('/^\s*Public Key Algorithm: ([^\s]+)$/m', $text,
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$algorithm))
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{
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trigger_error("checkDebianVulnerability(): Couldn't extract ".
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"the public key algorithm used", E_USER_WARNING);
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return null;
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} else {
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$algorithm = $algorithm[1];
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}
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if ($algorithm !== "rsaEncryption") return false;
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/* Extract public key size */
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if (!preg_match('/^\s*RSA Public Key: \((\d+) bit\)$/m', $text,
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$keysize))
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{
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trigger_error("checkDebianVulnerability(): Couldn't parse the ".
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"RSA key size", E_USER_WARNING);
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return null;
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} else {
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$keysize = intval($keysize[1]);
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}
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}
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// $keysize has been made sure to contain an int
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$blacklist = "/usr/share/openssl-blacklist/blacklist.RSA-$keysize";
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if (!(is_file($blacklist) && is_readable($blacklist)))
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{
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if (in_array($keysize, array(512, 1024, 2048, 4096)))
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{
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trigger_error("checkDebianVulnerability(): Blacklist for ".
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"$keysize bit keys not accessible. Expected at ".
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"$blacklist", E_USER_ERROR);
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return null;
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}
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trigger_error("checkDebianVulnerability(): $blacklist is not ".
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"readable. Unsupported key size?", E_USER_WARNING);
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return false;
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}
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/* Extract RSA modulus */
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if (!preg_match('/^\s*Modulus \(\d+ bit\):\n'.
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'((?:\s*[0-9a-f][0-9a-f]:(?:\n)?)+[0-9a-f][0-9a-f])$/m',
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$text, $modulus))
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{
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trigger_error("checkDebianVulnerability(): Couldn't extract the ".
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"RSA modulus", E_USER_WARNING);
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return null;
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} else {
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$modulus = $modulus[1];
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// strip whitespace and colon leftovers
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$modulus = str_replace(array(" ", "\t", "\n", ":"), "", $modulus);
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// when using "openssl xxx -text" first byte was 00 in all my test
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// cases but 00 not present in the "openssl xxx -modulus" output
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if ($modulus[0] === "0" && $modulus[1] === "0")
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{
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$modulus = substr($modulus, 2);
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} else {
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trigger_error("checkDebianVulnerability(): First byte is not ".
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"zero", E_USER_NOTICE);
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}
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$modulus = strtoupper($modulus);
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}
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/* calculate checksum and look it up in the blacklist */
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$checksum = substr(sha1("Modulus=$modulus\n"), 20);
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// $checksum and $blacklist should be safe, but just to make sure
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$checksum = escapeshellarg($checksum);
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$blacklist = escapeshellarg($blacklist);
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exec("grep $checksum $blacklist", $dummy, $debianVuln);
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if ($debianVuln === 0) // grep returned something => it is on the list
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{
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return true;
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} elseif ($debianVuln === 1) { // grep returned nothing
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return false;
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} else {
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trigger_error("checkDebianVulnerability(): Something went wrong ".
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"when looking up the key with checksum $checksum in the ".
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"blacklist $blacklist", E_USER_ERROR);
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return null;
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}
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// Should not get here
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return null;
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}
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?>
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323
includes/lib/check_weak_key.php
Normal file
323
includes/lib/check_weak_key.php
Normal file
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@ -0,0 +1,323 @@
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<?php /*
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LibreSSL - CAcert web application
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Copyright (C) 2004-2011 CAcert Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||||
|
GNU General Public License for more details.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU General Public License
|
||||||
|
along with this program; if not, write to the Free Software
|
||||||
|
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
||||||
|
*/
|
||||||
|
|
||||||
|
// failWithId()
|
||||||
|
require_once 'general.php';
|
||||||
|
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Checks whether the given CSR contains a vulnerable key
|
||||||
|
*
|
||||||
|
* @param $csr string
|
||||||
|
* The CSR to be checked
|
||||||
|
* @param $encoding string [optional]
|
||||||
|
* The encoding the CSR is in (for the "-inform" parameter of OpenSSL,
|
||||||
|
* currently only "PEM" (default) or "DER" allowed)
|
||||||
|
* @return string containing the reason if the key is considered weak,
|
||||||
|
* empty string otherwise
|
||||||
|
*/
|
||||||
|
function checkWeakKeyCSR($csr, $encoding = "PEM")
|
||||||
|
{
|
||||||
|
$encoding = escapeshellarg($encoding);
|
||||||
|
$status = runCommand("openssl req -inform $encoding -text -noout",
|
||||||
|
$csr, $csrText);
|
||||||
|
if ($status === true) {
|
||||||
|
return failWithId("checkWeakKeyCSR(): Failed to start OpenSSL");
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($status !== 0 || $csrText === "") {
|
||||||
|
return _("I didn't receive a valid Certificate Request. Hit ".
|
||||||
|
"the back button and try again.");
|
||||||
|
}
|
||||||
|
|
||||||
|
return checkWeakKeyText($csrText);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Checks whether the given X509 certificate contains a vulnerable key
|
||||||
|
*
|
||||||
|
* @param $cert string
|
||||||
|
* The X509 certificate to be checked
|
||||||
|
* @param $encoding string [optional]
|
||||||
|
* The encoding the certificate is in (for the "-inform" parameter of
|
||||||
|
* OpenSSL, currently only "PEM" (default), "DER" or "NET" allowed)
|
||||||
|
* @return string containing the reason if the key is considered weak,
|
||||||
|
* empty string otherwise
|
||||||
|
*/
|
||||||
|
function checkWeakKeyX509($cert, $encoding = "PEM")
|
||||||
|
{
|
||||||
|
$encoding = escapeshellarg($encoding);
|
||||||
|
$status = runCommand("openssl x509 -inform $encoding -text -noout",
|
||||||
|
$cert, $certText);
|
||||||
|
if ($status === true) {
|
||||||
|
return failWithId("checkWeakKeyX509(): Failed to start OpenSSL");
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($status !== 0 || $certText === "") {
|
||||||
|
return _("I didn't receive a valid Certificate Request. Hit ".
|
||||||
|
"the back button and try again.");
|
||||||
|
}
|
||||||
|
|
||||||
|
return checkWeakKeyText($certText);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Checks whether the given SPKAC contains a vulnerable key
|
||||||
|
*
|
||||||
|
* @param $spkac string
|
||||||
|
* The SPKAC to be checked
|
||||||
|
* @param $spkacname string [optional]
|
||||||
|
* The name of the variable that contains the SPKAC. The default is
|
||||||
|
* "SPKAC"
|
||||||
|
* @return string containing the reason if the key is considered weak,
|
||||||
|
* empty string otherwise
|
||||||
|
*/
|
||||||
|
function checkWeakKeySPKAC($spkac, $spkacname = "SPKAC")
|
||||||
|
{
|
||||||
|
$spkacname = escapeshellarg($spkacname);
|
||||||
|
$status = runCommand("openssl spkac -spkac $spkacname", $spkac, $spkacText);
|
||||||
|
if ($status === true) {
|
||||||
|
return failWithId("checkWeakKeySPKAC(): Failed to start OpenSSL");
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($status !== 0 || $spkacText === "") {
|
||||||
|
return _("I didn't receive a valid Certificate Request. Hit the ".
|
||||||
|
"back button and try again.");
|
||||||
|
}
|
||||||
|
|
||||||
|
return checkWeakKeyText($spkacText);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Checks whether the given text representation of a CSR or a SPKAC contains
|
||||||
|
* a weak key
|
||||||
|
*
|
||||||
|
* @param $text string
|
||||||
|
* The text representation of a key as output by the
|
||||||
|
* "openssl <foo> -text -noout" commands
|
||||||
|
* @return string containing the reason if the key is considered weak,
|
||||||
|
* empty string otherwise
|
||||||
|
*/
|
||||||
|
function checkWeakKeyText($text)
|
||||||
|
{
|
||||||
|
/* Which public key algorithm? */
|
||||||
|
if (!preg_match('/^\s*Public Key Algorithm: ([^\s]+)$/m', $text,
|
||||||
|
$algorithm))
|
||||||
|
{
|
||||||
|
return failWithId("checkWeakKeyText(): Couldn't extract the ".
|
||||||
|
"public key algorithm used.\nData:\n$text");
|
||||||
|
} else {
|
||||||
|
$algorithm = $algorithm[1];
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
if ($algorithm === "rsaEncryption")
|
||||||
|
{
|
||||||
|
if (!preg_match('/^\s*RSA Public Key: \((\d+) bit\)$/m', $text,
|
||||||
|
$keysize))
|
||||||
|
{
|
||||||
|
return failWithId("checkWeakKeyText(): Couldn't parse the RSA ".
|
||||||
|
"key size.\nData:\n$text");
|
||||||
|
} else {
|
||||||
|
$keysize = intval($keysize[1]);
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($keysize < 1024)
|
||||||
|
{
|
||||||
|
return sprintf(_("The keys that you use are very small ".
|
||||||
|
"and therefore insecure. Please generate stronger ".
|
||||||
|
"keys. More information about this issue can be ".
|
||||||
|
"found in %sthe wiki%s"),
|
||||||
|
"<a href='//wiki.cacert.org/WeakKeys#SmallKey'>",
|
||||||
|
"</a>");
|
||||||
|
} elseif ($keysize < 2048) {
|
||||||
|
// not critical but log so we have some statistics about
|
||||||
|
// affected users
|
||||||
|
trigger_error("checkWeakKeyText(): Certificate for small ".
|
||||||
|
"key (< 2048 bit) requested", E_USER_NOTICE);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
$debianVuln = checkDebianVulnerability($text, $keysize);
|
||||||
|
if ($debianVuln === true)
|
||||||
|
{
|
||||||
|
return sprintf(_("The keys you use have very likely been ".
|
||||||
|
"generated with a vulnerable version of OpenSSL which ".
|
||||||
|
"was distributed by debian. Please generate new keys. ".
|
||||||
|
"More information about this issue can be found in ".
|
||||||
|
"%sthe wiki%s"),
|
||||||
|
"<a href='//wiki.cacert.org/WeakKeys#DebianVulnerability'>",
|
||||||
|
"</a>");
|
||||||
|
} elseif ($debianVuln === false) {
|
||||||
|
// not vulnerable => do nothing
|
||||||
|
} else {
|
||||||
|
return failWithId("checkWeakKeyText(): Something went wrong in".
|
||||||
|
"checkDebianVulnerability().\nKeysize: $keysize\n".
|
||||||
|
"Data:\n$text");
|
||||||
|
}
|
||||||
|
|
||||||
|
if (!preg_match('/^\s*Exponent: (\d+) \(0x[0-9a-fA-F]+\)$/m', $text,
|
||||||
|
$exponent))
|
||||||
|
{
|
||||||
|
return failWithId("checkWeakKeyText(): Couldn't parse the RSA ".
|
||||||
|
"exponent.\nData:\n$text");
|
||||||
|
} else {
|
||||||
|
$exponent = $exponent[1]; // exponent might be very big =>
|
||||||
|
//handle as string using bc*()
|
||||||
|
|
||||||
|
if (bccomp($exponent, "3") === 0)
|
||||||
|
{
|
||||||
|
return sprintf(_("The keys you use might be insecure. ".
|
||||||
|
"Although there is currently no known attack for ".
|
||||||
|
"reasonable encryption schemes, we're being ".
|
||||||
|
"cautious and don't allow certificates for such ".
|
||||||
|
"keys. Please generate stronger keys. More ".
|
||||||
|
"information about this issue can be found in ".
|
||||||
|
"%sthe wiki%s"),
|
||||||
|
"<a href='//wiki.cacert.org/WeakKeys#SmallExponent'>",
|
||||||
|
"</a>");
|
||||||
|
} elseif (!(bccomp($exponent, "65537") >= 0 &&
|
||||||
|
(bccomp($exponent, "100000") === -1 ||
|
||||||
|
// speed things up if way smaller than 2^256
|
||||||
|
bccomp($exponent, bcpow("2", "256")) === -1) )) {
|
||||||
|
// 65537 <= exponent < 2^256 recommended by NIST
|
||||||
|
// not critical but log so we have some statistics about
|
||||||
|
// affected users
|
||||||
|
trigger_error("checkWeakKeyText(): Certificate for ".
|
||||||
|
"unsuitable exponent '$exponent' requested",
|
||||||
|
E_USER_NOTICE);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* No weakness found */
|
||||||
|
return "";
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Reimplement the functionality of the openssl-vulnkey tool
|
||||||
|
*
|
||||||
|
* @param $text string
|
||||||
|
* The text representation of a key as output by the
|
||||||
|
* "openssl <foo> -text -noout" commands
|
||||||
|
* @param $keysize int [optional]
|
||||||
|
* If the key size is already known it can be provided so it doesn't
|
||||||
|
* have to be parsed again. This also skips the check whether the key
|
||||||
|
* is an RSA key => use wisely
|
||||||
|
* @return TRUE if key is vulnerable, FALSE otherwise, NULL in case of error
|
||||||
|
*/
|
||||||
|
function checkDebianVulnerability($text, $keysize = 0)
|
||||||
|
{
|
||||||
|
$keysize = intval($keysize);
|
||||||
|
|
||||||
|
if ($keysize === 0)
|
||||||
|
{
|
||||||
|
/* Which public key algorithm? */
|
||||||
|
if (!preg_match('/^\s*Public Key Algorithm: ([^\s]+)$/m', $text,
|
||||||
|
$algorithm))
|
||||||
|
{
|
||||||
|
trigger_error("checkDebianVulnerability(): Couldn't extract ".
|
||||||
|
"the public key algorithm used.\nData:\n$text",
|
||||||
|
E_USER_WARNING);
|
||||||
|
return null;
|
||||||
|
} else {
|
||||||
|
$algorithm = $algorithm[1];
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($algorithm !== "rsaEncryption") return false;
|
||||||
|
|
||||||
|
/* Extract public key size */
|
||||||
|
if (!preg_match('/^\s*RSA Public Key: \((\d+) bit\)$/m', $text,
|
||||||
|
$keysize))
|
||||||
|
{
|
||||||
|
trigger_error("checkDebianVulnerability(): Couldn't parse the ".
|
||||||
|
"RSA key size.\nData:\n$text", E_USER_WARNING);
|
||||||
|
return null;
|
||||||
|
} else {
|
||||||
|
$keysize = intval($keysize[1]);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// $keysize has been made sure to contain an int
|
||||||
|
$blacklist = "/usr/share/openssl-blacklist/blacklist.RSA-$keysize";
|
||||||
|
if (!(is_file($blacklist) && is_readable($blacklist)))
|
||||||
|
{
|
||||||
|
if (in_array($keysize, array(512, 1024, 2048, 4096)))
|
||||||
|
{
|
||||||
|
trigger_error("checkDebianVulnerability(): Blacklist for ".
|
||||||
|
"$keysize bit keys not accessible. Expected at ".
|
||||||
|
"$blacklist", E_USER_ERROR);
|
||||||
|
return null;
|
||||||
|
}
|
||||||
|
|
||||||
|
trigger_error("checkDebianVulnerability(): $blacklist is not ".
|
||||||
|
"readable. Unsupported key size?", E_USER_WARNING);
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* Extract RSA modulus */
|
||||||
|
if (!preg_match('/^\s*Modulus \(\d+ bit\):\n'.
|
||||||
|
'((?:\s*[0-9a-f][0-9a-f]:(?:\n)?)+[0-9a-f][0-9a-f])$/m',
|
||||||
|
$text, $modulus))
|
||||||
|
{
|
||||||
|
trigger_error("checkDebianVulnerability(): Couldn't extract the ".
|
||||||
|
"RSA modulus.\nData:\n$text", E_USER_WARNING);
|
||||||
|
return null;
|
||||||
|
} else {
|
||||||
|
$modulus = $modulus[1];
|
||||||
|
// strip whitespace and colon leftovers
|
||||||
|
$modulus = str_replace(array(" ", "\t", "\n", ":"), "", $modulus);
|
||||||
|
|
||||||
|
// when using "openssl xxx -text" first byte was 00 in all my test
|
||||||
|
// cases but 00 not present in the "openssl xxx -modulus" output
|
||||||
|
if ($modulus[0] === "0" && $modulus[1] === "0")
|
||||||
|
{
|
||||||
|
$modulus = substr($modulus, 2);
|
||||||
|
} else {
|
||||||
|
trigger_error("checkDebianVulnerability(): First byte is not ".
|
||||||
|
"zero", E_USER_NOTICE);
|
||||||
|
}
|
||||||
|
|
||||||
|
$modulus = strtoupper($modulus);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* calculate checksum and look it up in the blacklist */
|
||||||
|
$checksum = substr(sha1("Modulus=$modulus\n"), 20);
|
||||||
|
|
||||||
|
// $checksum and $blacklist should be safe, but just to make sure
|
||||||
|
$checksum = escapeshellarg($checksum);
|
||||||
|
$blacklist = escapeshellarg($blacklist);
|
||||||
|
$debianVuln = runCommand("grep $checksum $blacklist");
|
||||||
|
if ($debianVuln === 0) // grep returned something => it is on the list
|
||||||
|
{
|
||||||
|
return true;
|
||||||
|
} elseif ($debianVuln === 1) {
|
||||||
|
// grep returned nothing
|
||||||
|
return false;
|
||||||
|
} else {
|
||||||
|
trigger_error("checkDebianVulnerability(): Something went wrong ".
|
||||||
|
"when looking up the key with checksum $checksum in the ".
|
||||||
|
"blacklist $blacklist", E_USER_ERROR);
|
||||||
|
return null;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Should not get here
|
||||||
|
return null;
|
||||||
|
}
|
||||||
|
|
@ -47,4 +47,86 @@ function get_user_id_from_cert($serial, $issuer_cn)
|
||||||
return -1;
|
return -1;
|
||||||
}
|
}
|
||||||
|
|
||||||
?>
|
/**
|
||||||
|
* Produces a log entry with the error message with log level E_USER_WARN
|
||||||
|
* and a random ID an returns a message that can be displayed to the user
|
||||||
|
* including the generated ID
|
||||||
|
*
|
||||||
|
* @param $errormessage string
|
||||||
|
* The error message that should be logged
|
||||||
|
* @return string containing the generated ID that can be displayed to the
|
||||||
|
* user
|
||||||
|
*/
|
||||||
|
function failWithId($errormessage) {
|
||||||
|
$errorId = rand();
|
||||||
|
trigger_error("$errormessage. ID: $errorId", E_USER_WARNING);
|
||||||
|
return sprintf(_("Something went wrong when processing your request. ".
|
||||||
|
"Please contact %s for help and provide them with the ".
|
||||||
|
"following ID: %d"),
|
||||||
|
"<a href='mailto:support@cacert.org?subject=System%20Error%20-%20".
|
||||||
|
"ID%3A%20$errorId'>support@cacert.org</a>",
|
||||||
|
$errorId);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Runs a command on the shell and return it's exit code and output
|
||||||
|
*
|
||||||
|
* @param string $command
|
||||||
|
* The command to run. Make sure that you escapeshellarg() any non-constant
|
||||||
|
* parts as this is executed on a shell!
|
||||||
|
* @param string|bool $input
|
||||||
|
* The input that is passed to the command via STDIN, if true the real
|
||||||
|
* STDIN is passed through
|
||||||
|
* @param string|bool $output
|
||||||
|
* The output the command wrote to STDOUT (this is passed as reference),
|
||||||
|
* if true the output will be written to the real STDOUT. Output is ignored
|
||||||
|
* by default
|
||||||
|
* @param string|bool $errors
|
||||||
|
* The output the command wrote to STDERR (this is passed as reference),
|
||||||
|
* if true (default) the output will be written to the real STDERR
|
||||||
|
*
|
||||||
|
* @return int|bool
|
||||||
|
* The exit code of the command, true if the execution of the command
|
||||||
|
* failed (true because then
|
||||||
|
* <code>if (runCommand('echo "foo"')) handle_error();</code> will work)
|
||||||
|
*/
|
||||||
|
function runCommand($command, $input = "", &$output = null, &$errors = true) {
|
||||||
|
$descriptorspec = array();
|
||||||
|
|
||||||
|
if ($input !== true) {
|
||||||
|
$descriptorspec[0] = array("pipe", "r"); // STDIN for child
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($output !== true) {
|
||||||
|
$descriptorspec[1] = array("pipe", "w"); // STDOUT for child
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($errors !== true) {
|
||||||
|
$descriptorspec[2] = array("pipe", "w"); // STDERR for child
|
||||||
|
}
|
||||||
|
|
||||||
|
$proc = proc_open($command, $descriptorspec, $pipes);
|
||||||
|
|
||||||
|
if (is_resource($proc))
|
||||||
|
{
|
||||||
|
if ($input !== true) {
|
||||||
|
fwrite($pipes[0], $input);
|
||||||
|
fclose($pipes[0]);
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($output !== true) {
|
||||||
|
$output = stream_get_contents($pipes[1]);
|
||||||
|
}
|
||||||
|
|
||||||
|
if ($errors !== true) {
|
||||||
|
$errors = stream_get_contents($pipes[2]);
|
||||||
|
}
|
||||||
|
|
||||||
|
return proc_close($proc);
|
||||||
|
|
||||||
|
} else {
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
|
||||||
|
|
@ -15,6 +15,9 @@
|
||||||
along with this program; if not, write to the Free Software
|
along with this program; if not, write to the Free Software
|
||||||
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
||||||
*/
|
*/
|
||||||
|
|
||||||
|
require_once '../../includes/lib/check_weak_key.php';
|
||||||
|
|
||||||
$username = mysql_real_escape_string($_REQUEST['username']);
|
$username = mysql_real_escape_string($_REQUEST['username']);
|
||||||
$password = mysql_real_escape_string($_REQUEST['password']);
|
$password = mysql_real_escape_string($_REQUEST['password']);
|
||||||
|
|
||||||
|
|
|
||||||
Loading…
Reference in a new issue