icinga2/lib/remote/jsonrpcconnection-pki.cpp

395 lines
13 KiB
C++

/******************************************************************************
* Icinga 2 *
* Copyright (C) 2012-2018 Icinga Development Team (https://www.icinga.com/) *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of the GNU General Public License *
* as published by the Free Software Foundation; either version 2 *
* of the License, or (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* 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 St, Fifth Floor, Boston, MA 02110-1301, USA. *
******************************************************************************/
#include "remote/jsonrpcconnection.hpp"
#include "remote/apilistener.hpp"
#include "remote/apifunction.hpp"
#include "remote/jsonrpc.hpp"
#include "base/configtype.hpp"
#include "base/objectlock.hpp"
#include "base/utility.hpp"
#include "base/logger.hpp"
#include "base/exception.hpp"
#include "base/convert.hpp"
#include <boost/thread/once.hpp>
#include <boost/regex.hpp>
#include <fstream>
using namespace icinga;
static Value RequestCertificateHandler(const MessageOrigin::Ptr& origin, const Dictionary::Ptr& params);
REGISTER_APIFUNCTION(RequestCertificate, pki, &RequestCertificateHandler);
static Value UpdateCertificateHandler(const MessageOrigin::Ptr& origin, const Dictionary::Ptr& params);
REGISTER_APIFUNCTION(UpdateCertificate, pki, &UpdateCertificateHandler);
Value RequestCertificateHandler(const MessageOrigin::Ptr& origin, const Dictionary::Ptr& params)
{
if (!params)
return Empty;
String certText = params->Get("cert_request");
std::shared_ptr<X509> cert;
Dictionary::Ptr result = new Dictionary();
/* Use the presented client certificate if not provided. */
if (certText.IsEmpty())
cert = origin->FromClient->GetStream()->GetPeerCertificate();
else
cert = StringToCertificate(certText);
ApiListener::Ptr listener = ApiListener::GetInstance();
std::shared_ptr<X509> cacert = GetX509Certificate(listener->GetDefaultCaPath());
String cn = GetCertificateCN(cert);
bool signedByCA = VerifyCertificate(cacert, cert);
Log(LogInformation, "JsonRpcConnection")
<< "Received certificate request for CN '" << cn << "'"
<< (signedByCA ? "" : " not") << " signed by our CA.";
if (signedByCA) {
time_t now;
time(&now);
/* auto-renew all certificates which were created before 2017 to force an update of the CA,
* because Icinga versions older than 2.4 sometimes create certificates with an invalid
* serial number. */
time_t forceRenewalEnd = 1483228800; /* January 1st, 2017 */
time_t renewalStart = now + 30 * 24 * 60 * 60;
if (X509_cmp_time(X509_get_notBefore(cert.get()), &forceRenewalEnd) != -1 && X509_cmp_time(X509_get_notAfter(cert.get()), &renewalStart) != -1) {
Log(LogInformation, "JsonRpcConnection")
<< "The certificate for CN '" << cn << "' cannot be renewed yet.";
result->Set("status_code", 1);
result->Set("error", "The certificate for CN '" + cn + "' cannot be renewed yet.");
return result;
}
}
unsigned int n;
unsigned char digest[EVP_MAX_MD_SIZE];
if (!X509_digest(cert.get(), EVP_sha256(), digest, &n)) {
result->Set("status_code", 1);
result->Set("error", "Could not calculate fingerprint for the X509 certificate for CN '" + cn + "'.");
Log(LogWarning, "JsonRpcConnection")
<< "Could not calculate fingerprint for the X509 certificate requested for CN '"
<< cn << "'.";
return result;
}
char certFingerprint[EVP_MAX_MD_SIZE*2+1];
for (unsigned int i = 0; i < n; i++)
sprintf(certFingerprint + 2 * i, "%02x", digest[i]);
result->Set("fingerprint_request", certFingerprint);
String requestDir = ApiListener::GetCertificateRequestsDir();
String requestPath = requestDir + "/" + certFingerprint + ".json";
result->Set("ca", CertificateToString(cacert));
JsonRpcConnection::Ptr client = origin->FromClient;
/* If we already have a signed certificate request, send it to the client. */
if (Utility::PathExists(requestPath)) {
Dictionary::Ptr request = Utility::LoadJsonFile(requestPath);
String certResponse = request->Get("cert_response");
if (!certResponse.IsEmpty()) {
Log(LogInformation, "JsonRpcConnection")
<< "Sending certificate response for CN '" << cn
<< "' to endpoint '" << client->GetIdentity() << "'.";
result->Set("cert", certResponse);
result->Set("status_code", 0);
Dictionary::Ptr message = new Dictionary({
{ "jsonrpc", "2.0" },
{ "method", "pki::UpdateCertificate" },
{ "params", result }
});
JsonRpc::SendMessage(client->GetStream(), message);
return result;
}
}
std::shared_ptr<X509> newcert;
std::shared_ptr<EVP_PKEY> pubkey;
X509_NAME *subject;
Dictionary::Ptr message;
String ticket;
/* Check whether we are a signing instance or we
* must delay the signing request.
*/
if (!Utility::PathExists(GetIcingaCADir() + "/ca.key"))
goto delayed_request;
if (!signedByCA) {
String salt = listener->GetTicketSalt();
ticket = params->Get("ticket");
/* Auto-signing is disabled by either a) no TicketSalt
* or b) the client did not include a ticket in its request.
*/
if (salt.IsEmpty() || ticket.IsEmpty())
goto delayed_request;
String realTicket = PBKDF2_SHA1(cn, salt, 50000);
if (ticket != realTicket) {
Log(LogWarning, "JsonRpcConnection")
<< "Ticket for CN '" << cn << "' is invalid.";
result->Set("status_code", 1);
result->Set("error", "Invalid ticket for CN '" + cn + "'.");
return result;
}
}
pubkey = std::shared_ptr<EVP_PKEY>(X509_get_pubkey(cert.get()), EVP_PKEY_free);
subject = X509_get_subject_name(cert.get());
newcert = CreateCertIcingaCA(pubkey.get(), subject);
/* verify that the new cert matches the CA we're using for the ApiListener;
* this ensures that the CA we have in /var/lib/icinga2/ca matches the one
* we're using for cluster connections (there's no point in sending a client
* a certificate it wouldn't be able to use to connect to us anyway) */
if (!VerifyCertificate(cacert, newcert)) {
Log(LogWarning, "JsonRpcConnection")
<< "The CA in '" << listener->GetDefaultCaPath() << "' does not match the CA which Icinga uses "
<< "for its own cluster connections. This is most likely a configuration problem.";
goto delayed_request;
}
/* Send the signed certificate update. */
Log(LogInformation, "JsonRpcConnection")
<< "Sending certificate response for CN '" << cn << "' to endpoint '"
<< client->GetIdentity() << "'" << (!ticket.IsEmpty() ? " (auto-signing ticket)" : "" ) << ".";
result->Set("cert", CertificateToString(newcert));
result->Set("status_code", 0);
message = new Dictionary({
{ "jsonrpc", "2.0" },
{ "method", "pki::UpdateCertificate" },
{ "params", result }
});
JsonRpc::SendMessage(client->GetStream(), message);
return result;
delayed_request:
/* Send a delayed certificate signing request. */
Utility::MkDirP(requestDir, 0700);
Dictionary::Ptr request = new Dictionary({
{ "cert_request", CertificateToString(cert) },
{ "ticket", params->Get("ticket") }
});
Utility::SaveJsonFile(requestPath, 0600, request);
JsonRpcConnection::SendCertificateRequest(nullptr, origin, requestPath);
result->Set("status_code", 2);
result->Set("error", "Certificate request for CN '" + cn + "' is pending. Waiting for approval from the parent Icinga instance.");
Log(LogInformation, "JsonRpcConnection")
<< "Certificate request for CN '" << cn << "' is pending. Waiting for approval.";
return result;
}
void JsonRpcConnection::SendCertificateRequest(const JsonRpcConnection::Ptr& aclient, const MessageOrigin::Ptr& origin, const String& path)
{
Dictionary::Ptr message = new Dictionary();
message->Set("jsonrpc", "2.0");
message->Set("method", "pki::RequestCertificate");
ApiListener::Ptr listener = ApiListener::GetInstance();
if (!listener)
return;
Dictionary::Ptr params = new Dictionary();
message->Set("params", params);
/* Path is empty if this is our own request. */
if (path.IsEmpty()) {
String ticketPath = ApiListener::GetCertsDir() + "/ticket";
std::ifstream fp(ticketPath.CStr());
String ticket((std::istreambuf_iterator<char>(fp)), std::istreambuf_iterator<char>());
fp.close();
params->Set("ticket", ticket);
} else {
Dictionary::Ptr request = Utility::LoadJsonFile(path);
if (request->Contains("cert_response"))
return;
params->Set("cert_request", request->Get("cert_request"));
params->Set("ticket", request->Get("ticket"));
}
/* Send the request to a) the connected client
* or b) the local zone and all parents.
*/
if (aclient)
JsonRpc::SendMessage(aclient->GetStream(), message);
else
listener->RelayMessage(origin, Zone::GetLocalZone(), message, false);
}
Value UpdateCertificateHandler(const MessageOrigin::Ptr& origin, const Dictionary::Ptr& params)
{
if (origin->FromZone && !Zone::GetLocalZone()->IsChildOf(origin->FromZone)) {
Log(LogWarning, "ClusterEvents")
<< "Discarding 'update certificate' message from '" << origin->FromClient->GetIdentity() << "': Invalid endpoint origin (client not allowed).";
return Empty;
}
String ca = params->Get("ca");
String cert = params->Get("cert");
ApiListener::Ptr listener = ApiListener::GetInstance();
if (!listener)
return Empty;
std::shared_ptr<X509> oldCert = GetX509Certificate(listener->GetDefaultCertPath());
std::shared_ptr<X509> newCert = StringToCertificate(cert);
String cn = GetCertificateCN(newCert);
Log(LogInformation, "JsonRpcConnection")
<< "Received certificate update message for CN '" << cn << "'";
/* Check if this is a certificate update for a subordinate instance. */
std::shared_ptr<EVP_PKEY> oldKey = std::shared_ptr<EVP_PKEY>(X509_get_pubkey(oldCert.get()), EVP_PKEY_free);
std::shared_ptr<EVP_PKEY> newKey = std::shared_ptr<EVP_PKEY>(X509_get_pubkey(newCert.get()), EVP_PKEY_free);
if (X509_NAME_cmp(X509_get_subject_name(oldCert.get()), X509_get_subject_name(newCert.get())) != 0 ||
EVP_PKEY_cmp(oldKey.get(), newKey.get()) != 1) {
String certFingerprint = params->Get("fingerprint_request");
/* Validate the fingerprint format. */
boost::regex expr("^[0-9a-f]+$");
if (!boost::regex_match(certFingerprint.GetData(), expr)) {
Log(LogWarning, "JsonRpcConnection")
<< "Endpoint '" << origin->FromClient->GetIdentity() << "' sent an invalid certificate fingerprint: '"
<< certFingerprint << "' for CN '" << cn << "'.";
return Empty;
}
String requestDir = ApiListener::GetCertificateRequestsDir();
String requestPath = requestDir + "/" + certFingerprint + ".json";
/* Save the received signed certificate request to disk. */
if (Utility::PathExists(requestPath)) {
Log(LogInformation, "JsonRpcConnection")
<< "Saved certificate update for CN '" << cn << "'";
Dictionary::Ptr request = Utility::LoadJsonFile(requestPath);
request->Set("cert_response", cert);
Utility::SaveJsonFile(requestPath, 0644, request);
}
return Empty;
}
/* Update CA certificate. */
String caPath = listener->GetDefaultCaPath();
Log(LogInformation, "JsonRpcConnection")
<< "Updating CA certificate in '" << caPath << "'.";
std::fstream cafp;
String tempCaPath = Utility::CreateTempFile(caPath + ".XXXXXX", 0644, cafp);
cafp << ca;
cafp.close();
#ifdef _WIN32
_unlink(caPath.CStr());
#endif /* _WIN32 */
if (rename(tempCaPath.CStr(), caPath.CStr()) < 0) {
BOOST_THROW_EXCEPTION(posix_error()
<< boost::errinfo_api_function("rename")
<< boost::errinfo_errno(errno)
<< boost::errinfo_file_name(tempCaPath));
}
/* Update signed certificate. */
String certPath = listener->GetDefaultCertPath();
Log(LogInformation, "JsonRpcConnection")
<< "Updating client certificate for CN '" << cn << "' in '" << certPath << "'.";
std::fstream certfp;
String tempCertPath = Utility::CreateTempFile(certPath + ".XXXXXX", 0644, certfp);
certfp << cert;
certfp.close();
#ifdef _WIN32
_unlink(certPath.CStr());
#endif /* _WIN32 */
if (rename(tempCertPath.CStr(), certPath.CStr()) < 0) {
BOOST_THROW_EXCEPTION(posix_error()
<< boost::errinfo_api_function("rename")
<< boost::errinfo_errno(errno)
<< boost::errinfo_file_name(tempCertPath));
}
/* Remove ticket for successful signing request. */
String ticketPath = ApiListener::GetCertsDir() + "/ticket";
if (unlink(ticketPath.CStr()) < 0 && errno != ENOENT) {
BOOST_THROW_EXCEPTION(posix_error()
<< boost::errinfo_api_function("unlink")
<< boost::errinfo_errno(errno)
<< boost::errinfo_file_name(ticketPath));
}
/* Update the certificates at runtime and reconnect all endpoints. */
Log(LogInformation, "JsonRpcConnection")
<< "Updating the client certificate for CN '" << cn << "' at runtime and reconnecting the endpoints.";
listener->UpdateSSLContext();
return Empty;
}