/*
* InspIRCd -- Internet Relay Chat Daemon
*
* Copyright (C) 2020 Matt Schatz <genius3000@g3k.solutions>
* Copyright (C) 2019 linuxdaemon <linuxdaemon.irc@gmail.com>
* Copyright (C) 2013-2014, 2016-2021 Sadie Powell <sadie@witchery.services>
* Copyright (C) 2013 Daniel Vassdal <shutter@canternet.org>
* Copyright (C) 2012-2017 Attila Molnar <attilamolnar@hush.com>
* Copyright (C) 2012-2013, 2016 Adam <Adam@anope.org>
* Copyright (C) 2012 Robby <robby@chatbelgie.be>
* Copyright (C) 2012 ChrisTX <xpipe@hotmail.de>
* Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
* Copyright (C) 2009 Uli Schlachter <psychon@inspircd.org>
* Copyright (C) 2008 Robin Burchell <robin+git@viroteck.net>
* Copyright (C) 2008 John Brooks <special@inspircd.org>
* Copyright (C) 2007-2008, 2010 Craig Edwards <brain@inspircd.org>
* Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
* Copyright (C) 2006 Oliver Lupton <om@inspircd.org>
*
* This file is part of InspIRCd. InspIRCd 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, version 2.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
/// $CompilerFlags: find_compiler_flags("gnutls")
/// $LinkerFlags: find_linker_flags("gnutls")
/// $PackageInfo: require_system("arch") gnutls pkgconf
/// $PackageInfo: require_system("centos") gnutls-devel pkgconfig
/// $PackageInfo: require_system("darwin") gnutls pkg-config
/// $PackageInfo: require_system("debian") gnutls-bin libgnutls28-dev pkg-config
/// $PackageInfo: require_system("ubuntu") gnutls-bin libgnutls28-dev pkg-config
#include "inspircd.h"
#include "modules/ssl.h"
#include <gnutls/gnutls.h>
#include <gnutls/crypto.h>
#include <gnutls/x509.h>
// Check if the GnuTLS library is at least version major.minor.patch
#define INSPIRCD_GNUTLS_HAS_VERSION(major, minor, patch) (GNUTLS_VERSION_NUMBER >= ((major << 16) | (minor << 8) | patch))
#ifdef _WIN32
# pragma comment(lib, "libgnutls-30.lib")
#endif
enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_HANDSHAKEN };
#if INSPIRCD_GNUTLS_HAS_VERSION(3, 3, 5)
#define INSPIRCD_GNUTLS_HAS_RECV_PACKET
#endif
#if INSPIRCD_GNUTLS_HAS_VERSION(3, 1, 9)
#define INSPIRCD_GNUTLS_HAS_CORK
#endif
static Module* thismod;
namespace GnuTLS
{
void GenRandom(char* buffer, size_t len)
{
gnutls_rnd(GNUTLS_RND_RANDOM, buffer, len);
}
class Init
{
public:
Init() { gnutls_global_init(); }
~Init() { gnutls_global_deinit(); }
};
class Exception : public ModuleException
{
public:
Exception(const std::string& reason)
: ModuleException(reason) { }
};
void ThrowOnError(int errcode, const char* msg)
{
if (errcode < 0)
{
std::string reason = msg;
reason.append(" :").append(gnutls_strerror(errcode));
throw Exception(reason);
}
}
/** Used to create a gnutls_datum_t* from a std::string
*/
class Datum
{
gnutls_datum_t datum;
public:
Datum(const std::string& dat)
{
datum.data = (unsigned char*)dat.data();
datum.size = static_cast<unsigned int>(dat.length());
}
const gnutls_datum_t* get() const { return &datum; }
};
class Hash
{
gnutls_digest_algorithm_t hash;
public:
// Nothing to deallocate, constructor may throw freely
Hash(const std::string& hashname)
{
// As gnutls_digest_algorithm_t and gnutls_mac_algorithm_t are mapped 1:1, we can do this
// There is no gnutls_dig_get_id() at the moment, but it may come later
hash = (gnutls_digest_algorithm_t)gnutls_mac_get_id(hashname.c_str());
if (hash == GNUTLS_DIG_UNKNOWN)
throw Exception("Unknown hash type " + hashname);
// Check if the user is giving us something that is a valid MAC but not digest
gnutls_hash_hd_t is_digest;
if (gnutls_hash_init(&is_digest, hash) < 0)
throw Exception("Unknown hash type " + hashname);
gnutls_hash_deinit(is_digest, NULL);
}
gnutls_digest_algorithm_t get() const { return hash; }
};
class DHParams
{
gnutls_dh_params_t dh_params;
DHParams()
{
ThrowOnError(gnutls_dh_params_init(&dh_params), "gnutls_dh_params_init() failed");
}
public:
/** Import */
static std::shared_ptr<DHParams> Import(const std::string& dhstr)
{
std::shared_ptr<DHParams> dh(new DHParams);
int ret = gnutls_dh_params_import_pkcs3(dh->dh_params, Datum(dhstr).get(), GNUTLS_X509_FMT_PEM);
ThrowOnError(ret, "Unable to import DH params");
return dh;
}
~DHParams()
{
gnutls_dh_params_deinit(dh_params);
}
const gnutls_dh_params_t& get() const { return dh_params; }
};
class X509Key
{
/** Ensure that the key is deinited in case the constructor of X509Key throws
*/
class RAIIKey
{
public:
gnutls_x509_privkey_t key;
RAIIKey()
{
ThrowOnError(gnutls_x509_privkey_init(&key), "gnutls_x509_privkey_init() failed");
}
~RAIIKey()
{
gnutls_x509_privkey_deinit(key);
}
} key;
public:
/** Import */
X509Key(const std::string& keystr)
{
int ret = gnutls_x509_privkey_import(key.key, Datum(keystr).get(), GNUTLS_X509_FMT_PEM);
ThrowOnError(ret, "Unable to import private key");
}
gnutls_x509_privkey_t& get() { return key.key; }
};
class X509CertList
{
std::vector<gnutls_x509_crt_t> certs;
public:
/** Import */
X509CertList(const std::string& certstr)
{
unsigned int certcount = 3;
certs.resize(certcount);
Datum datum(certstr);
int ret = gnutls_x509_crt_list_import(raw(), &certcount, datum.get(), GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
if (ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
{
// the buffer wasn't big enough to hold all certs but gnutls changed certcount to the number of available certs,
// try again with a bigger buffer
certs.resize(certcount);
ret = gnutls_x509_crt_list_import(raw(), &certcount, datum.get(), GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
}
ThrowOnError(ret, "Unable to load certificates");
// Resize the vector to the actual number of certs because we rely on its size being correct
// when deallocating the certs
certs.resize(certcount);
}
~X509CertList()
{
for (const auto& cert : certs)
gnutls_x509_crt_deinit(cert);
}
gnutls_x509_crt_t* raw() { return &certs[0]; }
size_t size() const { return certs.size(); }
};
class X509CRL
{
class RAIICRL
{
public:
gnutls_x509_crl_t crl;
RAIICRL()
{
ThrowOnError(gnutls_x509_crl_init(&crl), "gnutls_x509_crl_init() failed");
}
~RAIICRL()
{
gnutls_x509_crl_deinit(crl);
}
} crl;
public:
/** Import */
X509CRL(const std::string& crlstr)
{
int ret = gnutls_x509_crl_import(get(), Datum(crlstr).get(), GNUTLS_X509_FMT_PEM);
ThrowOnError(ret, "Unable to load certificate revocation list");
}
gnutls_x509_crl_t& get() { return crl.crl; }
};
class Priority
{
gnutls_priority_t priority;
public:
Priority(const std::string& priorities)
{
// Try to set the priorities for ciphers, kex methods etc. to the user supplied string
// If the user did not supply anything then the string is already set to "NORMAL"
const char* priocstr = priorities.c_str();
const char* prioerror;
int ret = gnutls_priority_init(&priority, priocstr, &prioerror);
if (ret < 0)
{
// gnutls did not understand the user supplied string
throw Exception("Unable to initialize priorities to \"" + priorities + "\": " + gnutls_strerror(ret) + " Syntax error at position " + ConvToStr((unsigned int) (prioerror - priocstr)));
}
}
~Priority()
{
gnutls_priority_deinit(priority);
}
void SetupSession(gnutls_session_t sess)
{
gnutls_priority_set(sess, priority);
}
static const char* GetDefault()
{
return "NORMAL:%SERVER_PRECEDENCE:-VERS-SSL3.0";
}
static std::string RemoveUnknownTokens(const std::string& prio)
{
std::string ret;
irc::sepstream ss(prio, ':');
for (std::string token; ss.GetToken(token); )
{
// Save current position so we can revert later if needed
const std::string::size_type prevpos = ret.length();
// Append next token
if (!ret.empty())
ret.push_back(':');
ret.append(token);
gnutls_priority_t test;
if (gnutls_priority_init(&test, ret.c_str(), NULL) < 0)
{
// The new token broke the priority string, revert to the previously working one
ServerInstance->Logs.Log(MODNAME, LOG_DEBUG, "Priority string token not recognized: \"%s\"", token.c_str());
ret.erase(prevpos);
}
else
{
// Worked
gnutls_priority_deinit(test);
}
}
return ret;
}
};
class CertCredentials
{
/** DH parameters associated with these credentials
*/
std::shared_ptr<DHParams> dh;
protected:
gnutls_certificate_credentials_t cred;
public:
CertCredentials()
{
ThrowOnError(gnutls_certificate_allocate_credentials(&cred), "Cannot allocate certificate credentials");
}
~CertCredentials()
{
gnutls_certificate_free_credentials(cred);
}
/** Associates these credentials with the session
*/
void SetupSession(gnutls_session_t sess)
{
gnutls_credentials_set(sess, GNUTLS_CRD_CERTIFICATE, cred);
}
/** Set the given DH parameters to be used with these credentials
*/
void SetDH(std::shared_ptr<DHParams>& DH)
{
dh = DH;
gnutls_certificate_set_dh_params(cred, dh->get());
}
};
class X509Credentials : public CertCredentials
{
/** Private key
*/
X509Key key;
/** Certificate list, presented to the peer
*/
X509CertList certs;
/** Trusted CA, may be NULL
*/
std::shared_ptr<X509CertList> trustedca;
/** Certificate revocation list, may be NULL
*/
std::shared_ptr<X509CRL> crl;
static int cert_callback(gnutls_session_t session, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, gnutls_retr2_st* st);
public:
X509Credentials(const std::string& certstr, const std::string& keystr)
: key(keystr)
, certs(certstr)
{
// Throwing is ok here, the destructor of Credentials is called in that case
int ret = gnutls_certificate_set_x509_key(cred, certs.raw(), static_cast<int>(certs.size()), key.get());
ThrowOnError(ret, "Unable to set cert/key pair");
gnutls_certificate_set_retrieve_function(cred, cert_callback);
}
/** Sets the trusted CA and the certificate revocation list
* to use when verifying certificates
*/
void SetCA(std::shared_ptr<X509CertList>& certlist, std::shared_ptr<X509CRL>& CRL)
{
// Do nothing if certlist is NULL
if (certlist.get())
{
int ret = gnutls_certificate_set_x509_trust(cred, certlist->raw(), static_cast<int>(certlist->size()));
ThrowOnError(ret, "gnutls_certificate_set_x509_trust() failed");
if (CRL.get())
{
ret = gnutls_certificate_set_x509_crl(cred, &CRL->get(), 1);
ThrowOnError(ret, "gnutls_certificate_set_x509_crl() failed");
}
trustedca = certlist;
crl = CRL;
}
}
};
class DataReader
{
ssize_t retval;
#ifdef INSPIRCD_GNUTLS_HAS_RECV_PACKET
gnutls_packet_t packet;
public:
DataReader(gnutls_session_t sess)
{
// Using the packet API avoids the final copy of the data which GnuTLS does if we supply
// our own buffer. Instead, we get the buffer containing the data from GnuTLS and copy it
// to the recvq directly from there in appendto().
retval = gnutls_record_recv_packet(sess, &packet);
}
void appendto(std::string& recvq)
{
// Copy data from GnuTLS buffers to recvq
gnutls_datum_t datum;
gnutls_packet_get(packet, &datum, NULL);
recvq.append(reinterpret_cast<const char*>(datum.data), datum.size);
gnutls_packet_deinit(packet);
}
#else
char* const buffer;
public:
DataReader(gnutls_session_t sess)
: buffer(ServerInstance->GetReadBuffer())
{
// Read data from GnuTLS buffers into ReadBuffer
retval = gnutls_record_recv(sess, buffer, ServerInstance->Config->NetBufferSize);
}
void appendto(std::string& recvq)
{
// Copy data from ReadBuffer to recvq
recvq.append(buffer, retval);
}
#endif
ssize_t ret() const { return retval; }
};
class Profile
{
/** Name of this profile
*/
const std::string name;
/** X509 certificate(s) and key
*/
X509Credentials x509cred;
/** The minimum length in bits for the DH prime to be accepted as a client
*/
unsigned int min_dh_bits;
/** Hashing algorithm to use when generating certificate fingerprints
*/
Hash hash;
/** Priorities for ciphers, compression methods, etc.
*/
Priority priority;
/** Rough max size of records to send
*/
const unsigned int outrecsize;
/** True to request a client certificate as a server
*/
const bool requestclientcert;
static std::string ReadFile(const std::string& filename)
{
FileReader reader(filename);
std::string ret = reader.GetString();
if (ret.empty())
throw Exception("Cannot read file " + filename);
return ret;
}
static std::string GetPrioStr(const std::string& profilename, std::shared_ptr<ConfigTag> tag)
{
// Use default priority string if this tag does not specify one
std::string priostr = GnuTLS::Priority::GetDefault();
bool found = tag->readString("priority", priostr);
// If the prio string isn't set in the config don't be strict about the default one because it doesn't work on all versions of GnuTLS
if (!tag->getBool("strictpriority", found))
{
std::string stripped = GnuTLS::Priority::RemoveUnknownTokens(priostr);
if (stripped.empty())
{
// Stripping failed, act as if a prio string wasn't set
stripped = GnuTLS::Priority::RemoveUnknownTokens(GnuTLS::Priority::GetDefault());
ServerInstance->Logs.Log(MODNAME, LOG_DEFAULT, "Priority string for profile \"%s\" contains unknown tokens and stripping it didn't yield a working one either, falling back to \"%s\"", profilename.c_str(), stripped.c_str());
}
else if ((found) && (stripped != priostr))
{
// Prio string was set in the config and we ended up with something that works but different
ServerInstance->Logs.Log(MODNAME, LOG_DEFAULT, "Priority string for profile \"%s\" contains unknown tokens, stripped to \"%s\"", profilename.c_str(), stripped.c_str());
}
priostr.swap(stripped);
}
return priostr;
}
public:
struct Config
{
std::string name;
std::shared_ptr<X509CertList> ca;
std::shared_ptr<X509CRL> crl;
std::string certstr;
std::string keystr;
std::shared_ptr<DHParams> dh;
std::string priostr;
unsigned int mindh;
std::string hashstr;
unsigned int outrecsize;
bool requestclientcert;
Config(const std::string& profilename, std::shared_ptr<ConfigTag> tag)
: name(profilename)
, certstr(ReadFile(tag->getString("certfile", "cert.pem", 1)))
, keystr(ReadFile(tag->getString("keyfile", "key.pem", 1)))
, dh(DHParams::Import(ReadFile(tag->getString("dhfile", "dhparams.pem", 1))))
, priostr(GetPrioStr(profilename, tag))
, mindh(static_cast<unsigned int>(tag->getUInt("mindhbits", 1024, 0, UINT32_MAX)))
, hashstr(tag->getString("hash", "sha256", 1))
, requestclientcert(tag->getBool("requestclientcert", true))
{
// Load trusted CA and revocation list, if set
std::string filename = tag->getString("cafile");
if (!filename.empty())
{
ca.reset(new X509CertList(ReadFile(filename)));
filename = tag->getString("crlfile");
if (!filename.empty())
crl.reset(new X509CRL(ReadFile(filename)));
}
#ifdef INSPIRCD_GNUTLS_HAS_CORK
// If cork support is available outrecsize represents the (rough) max amount of data we give GnuTLS while corked
outrecsize = static_cast<unsigned int>(tag->getUInt("outrecsize", 2048, 512, UINT32_MAX));
#else
outrecsize = static_cast<unsigned int>(tag->getUInt("outrecsize", 2048, 512, 16384));
#endif
}
};
Profile(Config& config)
: name(config.name)
, x509cred(config.certstr, config.keystr)
, min_dh_bits(config.mindh)
, hash(config.hashstr)
, priority(config.priostr)
, outrecsize(config.outrecsize)
, requestclientcert(config.requestclientcert)
{
x509cred.SetDH(config.dh);
x509cred.SetCA(config.ca, config.crl);
}
/** Set up the given session with the settings in this profile
*/
void SetupSession(gnutls_session_t sess)
{
priority.SetupSession(sess);
x509cred.SetupSession(sess);
gnutls_dh_set_prime_bits(sess, min_dh_bits);
// Request client certificate if enabled and we are a server, no-op if we're a client
if (requestclientcert)
gnutls_certificate_server_set_request(sess, GNUTLS_CERT_REQUEST);
}
const std::string& GetName() const { return name; }
X509Credentials& GetX509Credentials() { return x509cred; }
gnutls_digest_algorithm_t GetHash() const { return hash.get(); }
unsigned int GetOutgoingRecordSize() const { return outrecsize; }
};
}
class GnuTLSIOHook : public SSLIOHook
{
private:
gnutls_session_t sess = nullptr;
issl_status status = ISSL_NONE;
#ifdef INSPIRCD_GNUTLS_HAS_CORK
size_t gbuffersize = 0;
#endif
void CloseSession()
{
if (this->sess)
{
gnutls_bye(this->sess, GNUTLS_SHUT_WR);
gnutls_deinit(this->sess);
}
sess = NULL;
certificate = NULL;
status = ISSL_NONE;
}
// Returns 1 if handshake succeeded, 0 if it is still in progress, -1 if it failed
int Handshake(StreamSocket* user)
{
int ret = gnutls_handshake(this->sess);
if (ret < 0)
{
if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
{
// Handshake needs resuming later, read() or write() would have blocked.
this->status = ISSL_HANDSHAKING;
if (gnutls_record_get_direction(this->sess) == 0)
{
// gnutls_handshake() wants to read() again.
SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
}
else
{
// gnutls_handshake() wants to write() again.
SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
}
return 0;
}
else
{
user->SetError("Handshake Failed - " + std::string(gnutls_strerror(ret)));
CloseSession();
return -1;
}
}
else
{
// Change the session state
this->status = ISSL_HANDSHAKEN;
VerifyCertificate();
// Finish writing, if any left
SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
return 1;
}
}
void VerifyCertificate()
{
ssl_cert* certinfo = new ssl_cert;
this->certificate = certinfo;
unsigned int certstatus;
int ret = gnutls_certificate_verify_peers2(this->sess, &certstatus);
if (ret < 0)
{
certinfo->error = gnutls_strerror(ret);
return;
}
certinfo->invalid = (certstatus & GNUTLS_CERT_INVALID);
certinfo->unknownsigner = (certstatus & GNUTLS_CERT_SIGNER_NOT_FOUND);
certinfo->revoked = (certstatus & GNUTLS_CERT_REVOKED);
certinfo->trusted = !(certstatus & GNUTLS_CERT_SIGNER_NOT_CA);
if (gnutls_certificate_type_get(this->sess) != GNUTLS_CRT_X509)
{
certinfo->error = "No X509 keys sent";
return;
}
gnutls_x509_crt_t cert;
ret = gnutls_x509_crt_init(&cert);
if (ret < 0)
{
certinfo->error = gnutls_strerror(ret);
return;
}
char buffer[512];
size_t buffer_size = sizeof(buffer);
unsigned int cert_list_size = 0;
const gnutls_datum_t* cert_list = gnutls_certificate_get_peers(this->sess, &cert_list_size);
if (cert_list == NULL)
{
certinfo->error = "No certificate was found";
goto info_done_dealloc;
}
ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
if (ret < 0)
{
certinfo->error = gnutls_strerror(ret);
goto info_done_dealloc;
}
if (gnutls_x509_crt_get_dn(cert, buffer, &buffer_size) == 0)
{
// Make sure there are no chars in the string that we consider invalid.
certinfo->dn = buffer;
if (certinfo->dn.find_first_of("\r\n") != std::string::npos)
certinfo->dn.clear();
}
buffer_size = sizeof(buffer);
if (gnutls_x509_crt_get_issuer_dn(cert, buffer, &buffer_size) == 0)
{
// Make sure there are no chars in the string that we consider invalid.
certinfo->issuer = buffer;
if (certinfo->issuer.find_first_of("\r\n") != std::string::npos)
certinfo->issuer.clear();
}
buffer_size = sizeof(buffer);
if ((ret = gnutls_x509_crt_get_fingerprint(cert, GetProfile().GetHash(), buffer, &buffer_size)) < 0)
{
certinfo->error = gnutls_strerror(ret);
}
else
{
certinfo->fingerprint = Hex::Encode(buffer, buffer_size);
}
/* Beware here we do not check for errors.
*/
if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
{
certinfo->error = "Not activated, or expired certificate";
}
info_done_dealloc:
gnutls_x509_crt_deinit(cert);
}
// Returns 1 if application I/O should proceed, 0 if it must wait for the underlying protocol to progress, -1 on fatal error
int PrepareIO(StreamSocket* sock)
{
if (status == ISSL_HANDSHAKEN)
return 1;
else if (status == ISSL_HANDSHAKING)
{
// The handshake isn't finished, try to finish it
return Handshake(sock);
}
CloseSession();
sock->SetError("No TLS session");
return -1;
}
#ifdef INSPIRCD_GNUTLS_HAS_CORK
int FlushBuffer(StreamSocket* sock)
{
// If GnuTLS has some data buffered, write it
if (gbuffersize)
return HandleWriteRet(sock, gnutls_record_uncork(this->sess, 0));
return 1;
}
#endif
int HandleWriteRet(StreamSocket* sock, int ret)
{
if (ret > 0)
{
#ifdef INSPIRCD_GNUTLS_HAS_CORK
gbuffersize -= ret;
if (gbuffersize)
{
SocketEngine::ChangeEventMask(sock, FD_WANT_SINGLE_WRITE);
return 0;
}
#endif
return ret;
}
else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED || ret == 0)
{
SocketEngine::ChangeEventMask(sock, FD_WANT_SINGLE_WRITE);
return 0;
}
else // (ret < 0)
{
sock->SetError(gnutls_strerror(ret));
CloseSession();
return -1;
}
}
static const char* UnknownIfNULL(const char* str)
{
return str ? str : "UNKNOWN";
}
static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t session_wrap, void* buffer, size_t size)
{
StreamSocket* sock = reinterpret_cast<StreamSocket*>(session_wrap);
#ifdef _WIN32
GnuTLSIOHook* session = static_cast<GnuTLSIOHook*>(sock->GetModHook(thismod));
#endif
if (sock->GetEventMask() & FD_READ_WILL_BLOCK)
{
#ifdef _WIN32
gnutls_transport_set_errno(session->sess, EAGAIN);
#else
errno = EAGAIN;
#endif
return -1;
}
ssize_t rv = SocketEngine::Recv(sock, reinterpret_cast<char *>(buffer), size, 0);
#ifdef _WIN32
if (rv < 0)
{
/* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
* and then set errno appropriately.
* The gnutls library may also have a different errno variable than us, see
* gnutls_transport_set_errno(3).
*/
gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
}
#endif
if (rv < 0 || size_t(rv) < size)
SocketEngine::ChangeEventMask(sock, FD_READ_WILL_BLOCK);
return rv;
}
static ssize_t VectorPush(gnutls_transport_ptr_t transportptr, const giovec_t* iov, int iovcnt)
{
StreamSocket* sock = reinterpret_cast<StreamSocket*>(transportptr);
#ifdef _WIN32
GnuTLSIOHook* session = static_cast<GnuTLSIOHook*>(sock->GetModHook(thismod));
#endif
if (sock->GetEventMask() & FD_WRITE_WILL_BLOCK)
{
#ifdef _WIN32
gnutls_transport_set_errno(session->sess, EAGAIN);
#else
errno = EAGAIN;
#endif
return -1;
}
// Cast the giovec_t to iovec not to IOVector so the correct function is called on Windows
ssize_t ret = SocketEngine::WriteV(sock, reinterpret_cast<const iovec*>(iov), iovcnt);
#ifdef _WIN32
// See the function above for more info about the usage of gnutls_transport_set_errno() on Windows
if (ret < 0)
gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
#endif
ssize_t size = 0;
for (int i = 0; i < iovcnt; i++)
size += iov[i].iov_len;
if (ret < size)
SocketEngine::ChangeEventMask(sock, FD_WRITE_WILL_BLOCK);
return ret;
}
public:
GnuTLSIOHook(std::shared_ptr<IOHookProvider> hookprov, StreamSocket* sock, unsigned int flags)
: SSLIOHook(hookprov)
{
gnutls_init(&sess, flags);
gnutls_transport_set_ptr(sess, reinterpret_cast<gnutls_transport_ptr_t>(sock));
gnutls_transport_set_vec_push_function(sess, VectorPush);
gnutls_transport_set_pull_function(sess, gnutls_pull_wrapper);
GetProfile().SetupSession(sess);
sock->AddIOHook(this);
Handshake(sock);
}
void OnStreamSocketClose(StreamSocket* user) override
{
CloseSession();
}
int OnStreamSocketRead(StreamSocket* user, std::string& recvq) override
{
// Finish handshake if needed
int prepret = PrepareIO(user);
if (prepret <= 0)
return prepret;
// If we resumed the handshake then this->status will be ISSL_HANDSHAKEN.
{
GnuTLS::DataReader reader(sess);
ssize_t ret = reader.ret();
if (ret > 0)
{
reader.appendto(recvq);
// Schedule a read if there is still data in the GnuTLS buffer
if (gnutls_record_check_pending(sess) > 0)
SocketEngine::ChangeEventMask(user, FD_ADD_TRIAL_READ);
return 1;
}
else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
{
return 0;
}
else if (ret == 0)
{
user->SetError("Connection closed");
CloseSession();
return -1;
}
else
{
user->SetError(gnutls_strerror(int(ret)));
CloseSession();
return -1;
}
}
}
ssize_t OnStreamSocketWrite(StreamSocket* user, StreamSocket::SendQueue& sendq) override
{
// Finish handshake if needed
int prepret = PrepareIO(user);
if (prepret <= 0)
return prepret;
// Session is ready for transferring application data
#ifdef INSPIRCD_GNUTLS_HAS_CORK
while (true)
{
// If there is something in the GnuTLS buffer try to send() it
ssize_t ret = FlushBuffer(user);
if (ret <= 0)
return ret; // Couldn't flush entire buffer, retry later (or close on error)
// GnuTLS buffer is empty, if the sendq is empty as well then break to set FD_WANT_NO_WRITE
if (sendq.empty())
break;
// GnuTLS buffer is empty but sendq is not, begin sending data from the sendq
gnutls_record_cork(this->sess);
while ((!sendq.empty()) && (gbuffersize < GetProfile().GetOutgoingRecordSize()))
{
const StreamSocket::SendQueue::Element& elem = sendq.front();
gbuffersize += elem.length();
ret = gnutls_record_send(this->sess, elem.data(), elem.length());
if (ret < 0)
{
CloseSession();
return -1;
}
sendq.pop_front();
}
}
#else
int ret = 0;
while (!sendq.empty())
{
FlattenSendQueue(sendq, GetProfile().GetOutgoingRecordSize());
const StreamSocket::SendQueue::Element& buffer = sendq.front();
ret = HandleWriteRet(user, gnutls_record_send(this->sess, buffer.data(), buffer.length()));
if (ret <= 0)
return ret;
else if (ret < (int)buffer.length())
{
sendq.erase_front(ret);
SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
return 0;
}
// Wrote entire record, continue sending
sendq.pop_front();
}
#endif
SocketEngine::ChangeEventMask(user, FD_WANT_NO_WRITE);
return 1;
}
void GetCiphersuite(std::string& out) const override
{
if (!IsHandshakeDone())
return;
out.append(UnknownIfNULL(gnutls_protocol_get_name(gnutls_protocol_get_version(sess)))).push_back('-');
out.append(UnknownIfNULL(gnutls_kx_get_name(gnutls_kx_get(sess)))).push_back('-');
out.append(UnknownIfNULL(gnutls_cipher_get_name(gnutls_cipher_get(sess)))).push_back('-');
out.append(UnknownIfNULL(gnutls_mac_get_name(gnutls_mac_get(sess))));
}
bool GetServerName(std::string& out) const override
{
std::vector<char> nameBuffer;
size_t nameLength = 0;
unsigned int nameType = GNUTLS_NAME_DNS;
// First, determine the size of the hostname.
if (gnutls_server_name_get(sess, &nameBuffer[0], &nameLength, &nameType, 0) != GNUTLS_E_SHORT_MEMORY_BUFFER)
return false;
// Then retrieve the hostname.
nameBuffer.resize(nameLength);
if (gnutls_server_name_get(sess, &nameBuffer[0], &nameLength, &nameType, 0) != GNUTLS_E_SUCCESS)
return false;
out.append(&nameBuffer[0]);
return true;
}
GnuTLS::Profile& GetProfile();
bool IsHandshakeDone() const { return (status == ISSL_HANDSHAKEN); }
};
int GnuTLS::X509Credentials::cert_callback(gnutls_session_t sess, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, gnutls_retr2_st* st)
{
st->cert_type = GNUTLS_CRT_X509;
st->key_type = GNUTLS_PRIVKEY_X509;
StreamSocket* sock = reinterpret_cast<StreamSocket*>(gnutls_transport_get_ptr(sess));
GnuTLS::X509Credentials& cred = static_cast<GnuTLSIOHook*>(sock->GetModHook(thismod))->GetProfile().GetX509Credentials();
st->ncerts = static_cast<unsigned int>(cred.certs.size());
st->cert.x509 = cred.certs.raw();
st->key.x509 = cred.key.get();
st->deinit_all = 0;
return 0;
}
class GnuTLSIOHookProvider : public SSLIOHookProvider
{
GnuTLS::Profile profile;
public:
GnuTLSIOHookProvider(Module* mod, GnuTLS::Profile::Config& config)
: SSLIOHookProvider(mod, config.name)
, profile(config)
{
ServerInstance->Modules.AddService(*this);
}
~GnuTLSIOHookProvider() override
{
ServerInstance->Modules.DelService(*this);
}
void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) override
{
new GnuTLSIOHook(shared_from_this(), sock, GNUTLS_SERVER);
}
void OnConnect(StreamSocket* sock) override
{
new GnuTLSIOHook(shared_from_this(), sock, GNUTLS_CLIENT);
}
GnuTLS::Profile& GetProfile() { return profile; }
};
GnuTLS::Profile& GnuTLSIOHook::GetProfile()
{
return std::static_pointer_cast<GnuTLSIOHookProvider>(prov)->GetProfile();
}
class ModuleSSLGnuTLS : public Module
{
typedef std::vector<std::shared_ptr<GnuTLSIOHookProvider>> ProfileList;
// First member of the class, gets constructed first and destructed last
GnuTLS::Init libinit;
ProfileList profiles;
void ReadProfiles()
{
// First, store all profiles in a new, temporary container. If no problems occur, swap the two
// containers; this way if something goes wrong we can go back and continue using the current profiles,
// avoiding unpleasant situations where no new TLS connections are possible.
ProfileList newprofiles;
auto tags = ServerInstance->Config->ConfTags("sslprofile");
if (tags.empty())
throw ModuleException("You have not specified any <sslprofile> tags that are usable by this module!");
for (const auto& [_, tag] : tags)
{
if (!stdalgo::string::equalsci(tag->getString("provider"), "gnutls"))
{
ServerInstance->Logs.Log(MODNAME, LOG_DEFAULT, "Ignoring non-GnuTLS <sslprofile> tag at " + tag->source.str());
continue;
}
std::string name = tag->getString("name");
if (name.empty())
{
ServerInstance->Logs.Log(MODNAME, LOG_DEFAULT, "Ignoring <sslprofile> tag without name at " + tag->source.str());
continue;
}
std::shared_ptr<GnuTLSIOHookProvider> prov;
try
{
GnuTLS::Profile::Config profileconfig(name, tag);
prov = std::make_shared<GnuTLSIOHookProvider>(this, profileconfig);
}
catch (CoreException& ex)
{
throw ModuleException("Error while initializing TLS profile \"" + name + "\" at " + tag->source.str() + " - " + ex.GetReason());
}
newprofiles.push_back(prov);
}
// New profiles are ok, begin using them
// Old profiles are deleted when their refcount drops to zero
for (const auto& profile : profiles)
ServerInstance->Modules.DelService(*profile);
profiles.swap(newprofiles);
}
public:
ModuleSSLGnuTLS()
: Module(VF_VENDOR, "Allows TLS encrypted connections using the GnuTLS library.")
{
thismod = this;
}
void init() override
{
ServerInstance->Logs.Log(MODNAME, LOG_DEFAULT, "GnuTLS lib version %s module was compiled for " GNUTLS_VERSION, gnutls_check_version(NULL));
ServerInstance->GenRandom = GnuTLS::GenRandom;
}
void ReadConfig(ConfigStatus& status) override
{
auto tag = ServerInstance->Config->ConfValue("gnutls");
if (status.initial || tag->getBool("onrehash", true))
ReadProfiles();
}
void OnModuleRehash(User* user, const std::string ¶m) override
{
if (!irc::equals(param, "tls") && !irc::equals(param, "ssl"))
return;
try
{
ReadProfiles();
ServerInstance->SNO.WriteToSnoMask('a', "GnuTLS TLS profiles have been reloaded.");
}
catch (ModuleException& ex)
{
ServerInstance->Logs.Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings.");
}
}
~ModuleSSLGnuTLS() override
{
ServerInstance->GenRandom = &InspIRCd::DefaultGenRandom;
}
void OnCleanup(ExtensionItem::ExtensibleType type, Extensible* item) override
{
if (type == ExtensionItem::EXT_USER)
{
LocalUser* user = IS_LOCAL(static_cast<User*>(item));
if ((user) && (user->eh.GetModHook(this)))
{
// User is using TLS, they're a local user, and they're using one of *our* TLS ports.
// Potentially there could be multiple TLS modules loaded at once on different ports.
ServerInstance->Users.QuitUser(user, "GnuTLS module unloading");
}
}
}
ModResult OnCheckReady(LocalUser* user) override
{
const GnuTLSIOHook* const iohook = static_cast<GnuTLSIOHook*>(user->eh.GetModHook(this));
if ((iohook) && (!iohook->IsHandshakeDone()))
return MOD_RES_DENY;
return MOD_RES_PASSTHRU;
}
};
MODULE_INIT(ModuleSSLGnuTLS)
