diff options
Diffstat (limited to 'louloulibs/network')
| m--------- | louloulibs | 0 | ||||
| -rw-r--r-- | louloulibs/network/dns_handler.cpp | 112 | ||||
| -rw-r--r-- | louloulibs/network/dns_handler.hpp | 62 | ||||
| -rw-r--r-- | louloulibs/network/dns_socket_handler.cpp | 45 | ||||
| -rw-r--r-- | louloulibs/network/dns_socket_handler.hpp | 46 | ||||
| -rw-r--r-- | louloulibs/network/poller.cpp | 225 | ||||
| -rw-r--r-- | louloulibs/network/poller.hpp | 95 | ||||
| -rw-r--r-- | louloulibs/network/socket_handler.hpp | 45 | ||||
| -rw-r--r-- | louloulibs/network/tcp_socket_handler.cpp | 590 | ||||
| -rw-r--r-- | louloulibs/network/tcp_socket_handler.hpp | 293 |
10 files changed, 1513 insertions, 0 deletions
diff --git a/louloulibs b/louloulibs deleted file mode 160000 -Subproject 0f3c1183e2bf0941ae2bffd3f31577bce4f3001 diff --git a/louloulibs/network/dns_handler.cpp b/louloulibs/network/dns_handler.cpp new file mode 100644 index 0000000..ec53683 --- /dev/null +++ b/louloulibs/network/dns_handler.cpp @@ -0,0 +1,112 @@ +#include <louloulibs.h> +#ifdef CARES_FOUND + +#include <network/dns_socket_handler.hpp> +#include <network/tcp_socket_handler.hpp> +#include <network/dns_handler.hpp> +#include <network/poller.hpp> + +#include <algorithm> +#include <stdexcept> + +DNSHandler DNSHandler::instance; + +using namespace std::string_literals; + +void on_hostname4_resolved(void* arg, int status, int, struct hostent* hostent) +{ + TCPSocketHandler* socket_handler = static_cast<TCPSocketHandler*>(arg); + socket_handler->on_hostname4_resolved(status, hostent); +} + +void on_hostname6_resolved(void* arg, int status, int, struct hostent* hostent) +{ + TCPSocketHandler* socket_handler = static_cast<TCPSocketHandler*>(arg); + socket_handler->on_hostname6_resolved(status, hostent); +} + +DNSHandler::DNSHandler() +{ + int ares_error; + if ((ares_error = ::ares_library_init(ARES_LIB_INIT_ALL)) != 0) + throw std::runtime_error("Failed to initialize c-ares lib: "s + ares_strerror(ares_error)); + if ((ares_error = ::ares_init(&this->channel)) != ARES_SUCCESS) + throw std::runtime_error("Failed to initialize c-ares channel: "s + ares_strerror(ares_error)); +} + +ares_channel& DNSHandler::get_channel() +{ + return this->channel; +} + +void DNSHandler::destroy() +{ + this->socket_handlers.clear(); + ::ares_destroy(this->channel); + ::ares_library_cleanup(); +} + +void DNSHandler::gethostbyname(const std::string& name, + TCPSocketHandler* socket_handler, int family) +{ + socket_handler->free_cares_addrinfo(); + if (family == AF_INET) + ::ares_gethostbyname(this->channel, name.data(), family, + &::on_hostname4_resolved, socket_handler); + else + ::ares_gethostbyname(this->channel, name.data(), family, + &::on_hostname6_resolved, socket_handler); +} + +void DNSHandler::watch_dns_sockets(std::shared_ptr<Poller>& poller) +{ + fd_set readers; + fd_set writers; + + FD_ZERO(&readers); + FD_ZERO(&writers); + + int ndfs = ::ares_fds(this->channel, &readers, &writers); + // For each existing DNS socket, see if we are still supposed to watch it, + // if not then erase it + this->socket_handlers.erase( + std::remove_if(this->socket_handlers.begin(), this->socket_handlers.end(), + [&readers](const auto& dns_socket) + { + return !FD_ISSET(dns_socket->get_socket(), &readers); + }), + this->socket_handlers.end()); + + for (auto i = 0; i < ndfs; ++i) + { + bool read = FD_ISSET(i, &readers); + bool write = FD_ISSET(i, &writers); + // Look for the DNSSocketHandler with this fd + auto it = std::find_if(this->socket_handlers.begin(), + this->socket_handlers.end(), + [i](const auto& socket_handler) + { + return i == socket_handler->get_socket(); + }); + if (!read && !write) // No need to read or write to it + { // If found, erase it and stop watching it because it is not + // needed anymore + if (it != this->socket_handlers.end()) + // The socket destructor removes it from the poller + this->socket_handlers.erase(it); + } + else // We need to write and/or read to it + { // If not found, create it because we need to watch it + if (it == this->socket_handlers.end()) + { + this->socket_handlers.emplace_front(std::make_unique<DNSSocketHandler>(poller, i)); + it = this->socket_handlers.begin(); + } + poller->add_socket_handler(it->get()); + if (write) + poller->watch_send_events(it->get()); + } + } +} + +#endif /* CARES_FOUND */ diff --git a/louloulibs/network/dns_handler.hpp b/louloulibs/network/dns_handler.hpp new file mode 100644 index 0000000..a515f52 --- /dev/null +++ b/louloulibs/network/dns_handler.hpp @@ -0,0 +1,62 @@ +#ifndef DNS_HANDLER_HPP_INCLUDED +#define DNS_HANDLER_HPP_INCLUDED + +#include <louloulibs.h> +#ifdef CARES_FOUND + +class TCPSocketHandler; +class Poller; +class DNSSocketHandler; + +# include <ares.h> +# include <memory> +# include <string> +# include <list> + +void on_hostname4_resolved(void* arg, int status, int, struct hostent* hostent); +void on_hostname6_resolved(void* arg, int status, int, struct hostent* hostent); + +/** + * Class managing DNS resolution. It should only be statically instanciated + * once in SocketHandler. It manages ares channel and calls various + * functions of that library. + */ + +class DNSHandler +{ +public: + DNSHandler(); + ~DNSHandler() = default; + void gethostbyname(const std::string& name, TCPSocketHandler* socket_handler, + int family); + /** + * Call ares_fds to know what fd needs to be watched by the poller, create + * or destroy DNSSocketHandlers depending on the result. + */ + void watch_dns_sockets(std::shared_ptr<Poller>& poller); + /** + * Destroy and stop watching all the DNS sockets. Then de-init the channel + * and library. + */ + void destroy(); + ares_channel& get_channel(); + + static DNSHandler instance; + +private: + /** + * The list of sockets that needs to be watched, according to the last + * call to ares_fds. DNSSocketHandlers are added to it or removed from it + * in the watch_dns_sockets() method + */ + std::list<std::unique_ptr<DNSSocketHandler>> socket_handlers; + ares_channel channel; + + DNSHandler(const DNSHandler&) = delete; + DNSHandler(DNSHandler&&) = delete; + DNSHandler& operator=(const DNSHandler&) = delete; + DNSHandler& operator=(DNSHandler&&) = delete; +}; + +#endif /* CARES_FOUND */ +#endif /* DNS_HANDLER_HPP_INCLUDED */ diff --git a/louloulibs/network/dns_socket_handler.cpp b/louloulibs/network/dns_socket_handler.cpp new file mode 100644 index 0000000..124c9b2 --- /dev/null +++ b/louloulibs/network/dns_socket_handler.cpp @@ -0,0 +1,45 @@ +#include <louloulibs.h> +#ifdef CARES_FOUND + +#include <network/dns_socket_handler.hpp> +#include <network/dns_handler.hpp> +#include <network/poller.hpp> + +#include <ares.h> + +DNSSocketHandler::DNSSocketHandler(std::shared_ptr<Poller> poller, + const socket_t socket): + SocketHandler(poller, socket) +{ +} + +DNSSocketHandler::~DNSSocketHandler() +{ +} + +void DNSSocketHandler::connect() +{ +} + +void DNSSocketHandler::on_recv() +{ + // always stop watching send and read events. We will re-watch them if the + // next call to ares_fds tell us to + this->poller->remove_socket_handler(this->socket); + ::ares_process_fd(DNSHandler::instance.get_channel(), this->socket, ARES_SOCKET_BAD); +} + +void DNSSocketHandler::on_send() +{ + // always stop watching send and read events. We will re-watch them if the + // next call to ares_fds tell us to + this->poller->remove_socket_handler(this->socket); + ::ares_process_fd(DNSHandler::instance.get_channel(), ARES_SOCKET_BAD, this->socket); +} + +bool DNSSocketHandler::is_connected() const +{ + return true; +} + +#endif /* CARES_FOUND */ diff --git a/louloulibs/network/dns_socket_handler.hpp b/louloulibs/network/dns_socket_handler.hpp new file mode 100644 index 0000000..ad119e1 --- /dev/null +++ b/louloulibs/network/dns_socket_handler.hpp @@ -0,0 +1,46 @@ +#ifndef DNS_SOCKET_HANDLER_HPP +# define DNS_SOCKET_HANDLER_HPP + +#include <louloulibs.h> +#ifdef CARES_FOUND + +#include <network/socket_handler.hpp> +#include <ares.h> + +/** + * Manage a socket returned by ares_fds. We do not create, open or close the + * socket ourself: this is done by c-ares. We just call ares_process_fd() + * with the correct parameters, depending on what can be done on that socket + * (Poller reported it to be writable or readeable) + */ + +class DNSSocketHandler: public SocketHandler +{ +public: + explicit DNSSocketHandler(std::shared_ptr<Poller> poller, const socket_t socket); + ~DNSSocketHandler(); + /** + * Just call dns_process_fd, c-ares will do its work of send()ing or + * recv()ing the data it wants on that socket. + */ + void on_recv() override final; + void on_send() override final; + /** + * Do nothing, because we are always considered to be connected, since the + * connection is done by c-ares and not by us. + */ + void connect() override final; + /** + * Always true, see the comment for connect() + */ + bool is_connected() const override final; + +private: + DNSSocketHandler(const DNSSocketHandler&) = delete; + DNSSocketHandler(DNSSocketHandler&&) = delete; + DNSSocketHandler& operator=(const DNSSocketHandler&) = delete; + DNSSocketHandler& operator=(DNSSocketHandler&&) = delete; +}; + +#endif // CARES_FOUND +#endif // DNS_SOCKET_HANDLER_HPP diff --git a/louloulibs/network/poller.cpp b/louloulibs/network/poller.cpp new file mode 100644 index 0000000..329e1c8 --- /dev/null +++ b/louloulibs/network/poller.cpp @@ -0,0 +1,225 @@ +#include <network/poller.hpp> +#include <logger/logger.hpp> +#include <utils/timed_events.hpp> + +#include <assert.h> +#include <errno.h> +#include <stdio.h> +#include <signal.h> + +#include <cstring> +#include <iostream> +#include <stdexcept> + +Poller::Poller() +{ +#if POLLER == POLL + this->nfds = 0; +#elif POLLER == EPOLL + this->epfd = ::epoll_create1(0); + if (this->epfd == -1) + { + log_error("epoll failed: " << strerror(errno)); + throw std::runtime_error("Could not create epoll instance"); + } +#endif +} + +Poller::~Poller() +{ +} + +void Poller::add_socket_handler(SocketHandler* socket_handler) +{ + // Don't do anything if the socket is already managed + const auto it = this->socket_handlers.find(socket_handler->get_socket()); + if (it != this->socket_handlers.end()) + return ; + + this->socket_handlers.emplace(socket_handler->get_socket(), socket_handler); + + // We always watch all sockets for receive events +#if POLLER == POLL + this->fds[this->nfds].fd = socket_handler->get_socket(); + this->fds[this->nfds].events = POLLIN; + this->nfds++; +#endif +#if POLLER == EPOLL + struct epoll_event event = {EPOLLIN, {socket_handler}}; + const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_ADD, socket_handler->get_socket(), &event); + if (res == -1) + { + log_error("epoll_ctl failed: " << strerror(errno)); + throw std::runtime_error("Could not add socket to epoll"); + } +#endif +} + +void Poller::remove_socket_handler(const socket_t socket) +{ + const auto it = this->socket_handlers.find(socket); + if (it == this->socket_handlers.end()) + throw std::runtime_error("Trying to remove a SocketHandler that is not managed"); + this->socket_handlers.erase(it); + +#if POLLER == POLL + for (size_t i = 0; i < this->nfds; i++) + { + if (this->fds[i].fd == socket) + { + // Move all subsequent pollfd by one on the left, erasing the + // value of the one we remove + for (size_t j = i; j < this->nfds - 1; ++j) + { + this->fds[j].fd = this->fds[j+1].fd; + this->fds[j].events= this->fds[j+1].events; + } + this->nfds--; + } + } +#elif POLLER == EPOLL + const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_DEL, socket, nullptr); + if (res == -1) + { + log_error("epoll_ctl failed: " << strerror(errno)); + throw std::runtime_error("Could not remove socket from epoll"); + } +#endif +} + +void Poller::watch_send_events(SocketHandler* socket_handler) +{ +#if POLLER == POLL + for (size_t i = 0; i <= this->nfds; ++i) + { + if (this->fds[i].fd == socket_handler->get_socket()) + { + this->fds[i].events = POLLIN|POLLOUT; + return; + } + } + throw std::runtime_error("Cannot watch a non-registered socket for send events"); +#elif POLLER == EPOLL + struct epoll_event event = {EPOLLIN|EPOLLOUT, {socket_handler}}; + const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_MOD, socket_handler->get_socket(), &event); + if (res == -1) + { + log_error("epoll_ctl failed: " << strerror(errno)); + throw std::runtime_error("Could not modify socket flags in epoll"); + } +#endif +} + +void Poller::stop_watching_send_events(SocketHandler* socket_handler) +{ +#if POLLER == POLL + for (size_t i = 0; i <= this->nfds; ++i) + { + if (this->fds[i].fd == socket_handler->get_socket()) + { + this->fds[i].events = POLLIN; + return; + } + } + throw std::runtime_error("Cannot watch a non-registered socket for send events"); +#elif POLLER == EPOLL + struct epoll_event event = {EPOLLIN, {socket_handler}}; + const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_MOD, socket_handler->get_socket(), &event); + if (res == -1) + { + log_error("epoll_ctl failed: " << strerror(errno)); + throw std::runtime_error("Could not modify socket flags in epoll"); + } +#endif +} + +int Poller::poll(const std::chrono::milliseconds& timeout) +{ + if (this->socket_handlers.empty() && timeout == utils::no_timeout) + return -1; +#if POLLER == POLL + // Convert our nice timeout into this ugly struct + struct timespec timeout_ts; + struct timespec* timeout_tsp; + if (timeout > 0s) + { + auto seconds = std::chrono::duration_cast<std::chrono::seconds>(timeout); + timeout_ts.tv_sec = seconds.count(); + timeout_ts.tv_nsec = std::chrono::duration_cast<std::chrono::nanoseconds>(timeout - seconds).count(); + timeout_tsp = &timeout_ts; + } + else + timeout_tsp = nullptr; + + // Unblock all signals, only during the ppoll call + sigset_t empty_signal_set; + sigemptyset(&empty_signal_set); + int nb_events = ::ppoll(this->fds, this->nfds, timeout_tsp, + &empty_signal_set); + if (nb_events < 0) + { + if (errno == EINTR) + return true; + log_error("poll failed: " << strerror(errno)); + throw std::runtime_error("Poll failed"); + } + // We cannot possibly have more ready events than the number of fds we are + // watching + assert(static_cast<unsigned int>(nb_events) <= this->nfds); + for (size_t i = 0; i <= this->nfds && nb_events != 0; ++i) + { + if (this->fds[i].revents == 0) + continue; + else if (this->fds[i].revents & POLLIN) + { + auto socket_handler = this->socket_handlers.at(this->fds[i].fd); + socket_handler->on_recv(); + nb_events--; + } + else if (this->fds[i].revents & POLLOUT) + { + auto socket_handler = this->socket_handlers.at(this->fds[i].fd); + if (socket_handler->is_connected()) + socket_handler->on_send(); + else + socket_handler->connect(); + nb_events--; + } + } + return 1; +#elif POLLER == EPOLL + static const size_t max_events = 12; + struct epoll_event revents[max_events]; + // Unblock all signals, only during the epoll_pwait call + sigset_t empty_signal_set; + sigemptyset(&empty_signal_set); + const int nb_events = ::epoll_pwait(this->epfd, revents, max_events, timeout.count(), + &empty_signal_set); + if (nb_events == -1) + { + if (errno == EINTR) + return 0; + log_error("epoll wait: " << strerror(errno)); + throw std::runtime_error("Epoll_wait failed"); + } + for (int i = 0; i < nb_events; ++i) + { + auto socket_handler = static_cast<SocketHandler*>(revents[i].data.ptr); + if (revents[i].events & EPOLLIN) + socket_handler->on_recv(); + else if (revents[i].events & EPOLLOUT) + { + if (socket_handler->is_connected()) + socket_handler->on_send(); + else + socket_handler->connect(); + } + } + return nb_events; +#endif +} + +size_t Poller::size() const +{ + return this->socket_handlers.size(); +} diff --git a/louloulibs/network/poller.hpp b/louloulibs/network/poller.hpp new file mode 100644 index 0000000..de0cb48 --- /dev/null +++ b/louloulibs/network/poller.hpp @@ -0,0 +1,95 @@ +#ifndef POLLER_INCLUDED +# define POLLER_INCLUDED + +#include <network/socket_handler.hpp> + +#include <unordered_map> +#include <memory> +#include <chrono> + +#define POLL 1 +#define EPOLL 2 +#define KQUEUE 3 +#include <louloulibs.h> +#ifndef POLLER + #define POLLER POLL +#endif + +#if POLLER == POLL + #include <poll.h> + #define MAX_POLL_FD_NUMBER 4096 +#elif POLLER == EPOLL + #include <sys/epoll.h> +#else + #error Invalid POLLER value +#endif + +/** + * We pass some SocketHandlers to this Poller, which uses + * poll/epoll/kqueue/select etc to wait for events on these SocketHandlers, + * and call the callbacks when event occurs. + * + * TODO: support these pollers: + * - kqueue(2) + */ + +class Poller +{ +public: + explicit Poller(); + ~Poller(); + /** + * Add a SocketHandler to be monitored by this Poller. All receive events + * are always automatically watched. + */ + void add_socket_handler(SocketHandler* socket_handler); + /** + * Remove (and stop managing) a SocketHandler, designated by the given socket_t. + */ + void remove_socket_handler(const socket_t socket); + /** + * Signal the poller that he needs to watch for send events for the given + * SocketHandler. + */ + void watch_send_events(SocketHandler* socket_handler); + /** + * Signal the poller that he needs to stop watching for send events for + * this SocketHandler. + */ + void stop_watching_send_events(SocketHandler* socket_handler); + /** + * Wait for all watched events, and call the SocketHandlers' callbacks + * when one is ready. Returns if nothing happened before the provided + * timeout. If the timeout is 0, it waits forever. If there is no + * watched event, returns -1 immediately, ignoring the timeout value. + * Otherwise, returns the number of event handled. If 0 is returned this + * means that we were interrupted by a signal, or the timeout occured. + */ + int poll(const std::chrono::milliseconds& timeout); + /** + * Returns the number of SocketHandlers managed by the poller. + */ + size_t size() const; + +private: + /** + * A "list" of all the SocketHandlers that we manage, indexed by socket, + * because that's what is returned by select/poll/etc when an event + * occures. + */ + std::unordered_map<socket_t, SocketHandler*> socket_handlers; + +#if POLLER == POLL + struct pollfd fds[MAX_POLL_FD_NUMBER]; + nfds_t nfds; +#elif POLLER == EPOLL + int epfd; +#endif + + Poller(const Poller&) = delete; + Poller(Poller&&) = delete; + Poller& operator=(const Poller&) = delete; + Poller& operator=(Poller&&) = delete; +}; + +#endif // POLLER_INCLUDED diff --git a/louloulibs/network/socket_handler.hpp b/louloulibs/network/socket_handler.hpp new file mode 100644 index 0000000..d01ac5d --- /dev/null +++ b/louloulibs/network/socket_handler.hpp @@ -0,0 +1,45 @@ +#ifndef SOCKET_HANDLER_HPP +# define SOCKET_HANDLER_HPP + +#include <louloulibs.h> +#include <memory> + +class Poller; + +typedef int socket_t; + +class SocketHandler +{ +public: + explicit SocketHandler(std::shared_ptr<Poller> poller, const socket_t socket): + poller(poller), + socket(socket) + {} + virtual ~SocketHandler() {} + virtual void on_recv() = 0; + virtual void on_send() = 0; + virtual void connect() = 0; + virtual bool is_connected() const = 0; + + socket_t get_socket() const + { return this->socket; } + +protected: + /** + * A pointer to the poller that manages us, because we need to communicate + * with it. + */ + std::shared_ptr<Poller> poller; + /** + * The handled socket. + */ + socket_t socket; + +private: + SocketHandler(const SocketHandler&) = delete; + SocketHandler(SocketHandler&&) = delete; + SocketHandler& operator=(const SocketHandler&) = delete; + SocketHandler& operator=(SocketHandler&&) = delete; +}; + +#endif // SOCKET_HANDLER_HPP diff --git a/louloulibs/network/tcp_socket_handler.cpp b/louloulibs/network/tcp_socket_handler.cpp new file mode 100644 index 0000000..f647b86 --- /dev/null +++ b/louloulibs/network/tcp_socket_handler.cpp @@ -0,0 +1,590 @@ +#include <network/tcp_socket_handler.hpp> +#include <network/dns_handler.hpp> + +#include <utils/timed_events.hpp> +#include <utils/scopeguard.hpp> +#include <network/poller.hpp> + +#include <logger/logger.hpp> +#include <sys/socket.h> +#include <sys/types.h> +#include <stdexcept> +#include <unistd.h> +#include <errno.h> +#include <netdb.h> +#include <cstring> +#include <fcntl.h> + +#include <iostream> + +#ifdef BOTAN_FOUND +# include <botan/hex.h> + +Botan::AutoSeeded_RNG TCPSocketHandler::rng; +Permissive_Credentials_Manager TCPSocketHandler::credential_manager; +Botan::TLS::Policy TCPSocketHandler::policy; +Botan::TLS::Session_Manager_In_Memory TCPSocketHandler::session_manager(TCPSocketHandler::rng); + +#endif + +#ifndef UIO_FASTIOV +# define UIO_FASTIOV 8 +#endif + +using namespace std::string_literals; +using namespace std::chrono_literals; + +namespace ph = std::placeholders; + +TCPSocketHandler::TCPSocketHandler(std::shared_ptr<Poller> poller): + SocketHandler(poller, -1), + use_tls(false), + connected(false), + connecting(false) +#ifdef CARES_FOUND + ,resolving(false), + resolved(false), + resolved4(false), + resolved6(false), + cares_addrinfo(nullptr), + cares_error() +#endif +{} + +TCPSocketHandler::~TCPSocketHandler() +{ +#ifdef CARES_FOUND + this->free_cares_addrinfo(); +#endif +} + +void TCPSocketHandler::init_socket(const struct addrinfo* rp) +{ + if ((this->socket = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol)) == -1) + throw std::runtime_error("Could not create socket: "s + strerror(errno)); + int optval = 1; + if (::setsockopt(this->socket, SOL_SOCKET, SO_KEEPALIVE, &optval, sizeof(optval)) == -1) + log_warning("Failed to enable TCP keepalive on socket: " << strerror(errno)); + // Set the socket on non-blocking mode. This is useful to receive a EAGAIN + // error when connect() would block, to not block the whole process if a + // remote is not responsive. + const int existing_flags = ::fcntl(this->socket, F_GETFL, 0); + if ((existing_flags == -1) || + (::fcntl(this->socket, F_SETFL, existing_flags | O_NONBLOCK) == -1)) + throw std::runtime_error("Could not initialize socket: "s + strerror(errno)); +} + +void TCPSocketHandler::connect(const std::string& address, const std::string& port, const bool tls) +{ + this->address = address; + this->port = port; + this->use_tls = tls; + + utils::ScopeGuard sg; + + struct addrinfo* addr_res; + + if (!this->connecting) + { + // Get the addrinfo from getaddrinfo (or ares_gethostbyname), only if + // this is the first call of this function. +#ifdef CARES_FOUND + if (!this->resolved) + { + log_info("Trying to connect to " << address << ":" << port); + // Start the asynchronous process of resolving the hostname. Once + // the addresses have been found and `resolved` has been set to true + // (but connecting will still be false), TCPSocketHandler::connect() + // needs to be called, again. + this->resolving = true; + DNSHandler::instance.gethostbyname(address, this, AF_INET6); + DNSHandler::instance.gethostbyname(address, this, AF_INET); + return; + } + else + { + // The c-ares resolved the hostname and the available addresses + // where saved in the cares_addrinfo linked list. Now, just use + // this list to try to connect. + addr_res = this->cares_addrinfo; + if (!addr_res) + { + this->close(); + this->on_connection_failed(this->cares_error); + return ; + } + } +#else + log_info("Trying to connect to " << address << ":" << port); + struct addrinfo hints; + memset(&hints, 0, sizeof(struct addrinfo)); + hints.ai_flags = 0; + hints.ai_family = AF_UNSPEC; + hints.ai_socktype = SOCK_STREAM; + hints.ai_protocol = 0; + + const int res = ::getaddrinfo(address.c_str(), port.c_str(), &hints, &addr_res); + + if (res != 0) + { + log_warning("getaddrinfo failed: "s + gai_strerror(res)); + this->close(); + this->on_connection_failed(gai_strerror(res)); + return ; + } + // Make sure the alloced structure is always freed at the end of the + // function + sg.add_callback([&addr_res](){ freeaddrinfo(addr_res); }); +#endif + } + else + { // This function is called again, use the saved addrinfo structure, + // instead of re-doing the whole getaddrinfo process. + addr_res = &this->addrinfo; + } + + for (struct addrinfo* rp = addr_res; rp; rp = rp->ai_next) + { + if (!this->connecting) + { + try { + this->init_socket(rp); + } + catch (const std::runtime_error& error) { + log_error("Failed to init socket: " << error.what()); + break; + } + } + if (::connect(this->socket, rp->ai_addr, rp->ai_addrlen) == 0 + || errno == EISCONN) + { + log_info("Connection success."); + TimedEventsManager::instance().cancel("connection_timeout"s + + std::to_string(this->socket)); + this->poller->add_socket_handler(this); + this->connected = true; + this->connecting = false; +#ifdef BOTAN_FOUND + if (this->use_tls) + this->start_tls(); +#endif + this->on_connected(); + return ; + } + else if (errno == EINPROGRESS || errno == EALREADY) + { // retry this process later, when the socket + // is ready to be written on. + this->connecting = true; + this->poller->add_socket_handler(this); + this->poller->watch_send_events(this); + // Save the addrinfo structure, to use it on the next call + this->ai_addrlen = rp->ai_addrlen; + memcpy(&this->ai_addr, rp->ai_addr, this->ai_addrlen); + memcpy(&this->addrinfo, rp, sizeof(struct addrinfo)); + this->addrinfo.ai_addr = reinterpret_cast<struct sockaddr*>(&this->ai_addr); + this->addrinfo.ai_next = nullptr; + // If the connection has not succeeded or failed in 5s, we consider + // it to have failed + TimedEventsManager::instance().add_event( + TimedEvent(std::chrono::steady_clock::now() + 5s, + std::bind(&TCPSocketHandler::on_connection_timeout, this), + "connection_timeout"s + std::to_string(this->socket))); + return ; + } + log_info("Connection failed:" << strerror(errno)); + } + log_error("All connection attempts failed."); + this->close(); + this->on_connection_failed(strerror(errno)); + return ; +} + +void TCPSocketHandler::on_connection_timeout() +{ + this->close(); + this->on_connection_failed("connection timed out"); +} + +void TCPSocketHandler::connect() +{ + this->connect(this->address, this->port, this->use_tls); +} + +void TCPSocketHandler::on_recv() +{ +#ifdef BOTAN_FOUND + if (this->use_tls) + this->tls_recv(); + else +#endif + this->plain_recv(); +} + +void TCPSocketHandler::plain_recv() +{ + static constexpr size_t buf_size = 4096; + char buf[buf_size]; + void* recv_buf = this->get_receive_buffer(buf_size); + + if (recv_buf == nullptr) + recv_buf = buf; + + const ssize_t size = this->do_recv(recv_buf, buf_size); + + if (size > 0) + { + if (buf == recv_buf) + { + // data needs to be placed in the in_buf string, because no buffer + // was provided to receive that data directly. The in_buf buffer + // will be handled in parse_in_buffer() + this->in_buf += std::string(buf, size); + } + this->parse_in_buffer(size); + } +} + +ssize_t TCPSocketHandler::do_recv(void* recv_buf, const size_t buf_size) +{ + ssize_t size = ::recv(this->socket, recv_buf, buf_size, 0); + if (0 == size) + { + this->on_connection_close(""); + this->close(); + } + else if (-1 == size) + { + log_warning("Error while reading from socket: " << strerror(errno)); + // Remember if we were connecting, or already connected when this + // happened, because close() sets this->connecting to false + const auto were_connecting = this->connecting; + this->close(); + if (were_connecting) + this->on_connection_failed(strerror(errno)); + else + this->on_connection_close(strerror(errno)); + } + return size; +} + +void TCPSocketHandler::on_send() +{ + struct iovec msg_iov[UIO_FASTIOV] = {}; + struct msghdr msg{nullptr, 0, + msg_iov, + 0, nullptr, 0, 0}; + for (std::string& s: this->out_buf) + { + // unconsting the content of s is ok, sendmsg will never modify it + msg_iov[msg.msg_iovlen].iov_base = const_cast<char*>(s.data()); + msg_iov[msg.msg_iovlen].iov_len = s.size(); + if (++msg.msg_iovlen == UIO_FASTIOV) + break; + } + ssize_t res = ::sendmsg(this->socket, &msg, MSG_NOSIGNAL); + if (res < 0) + { + log_error("sendmsg failed: " << strerror(errno)); + this->on_connection_close(strerror(errno)); + this->close(); + } + else + { + // remove all the strings that were successfully sent. + for (auto it = this->out_buf.begin(); + it != this->out_buf.end();) + { + if (static_cast<size_t>(res) >= (*it).size()) + { + res -= (*it).size(); + it = this->out_buf.erase(it); + } + else + { + // If one string has partially been sent, we use substr to + // crop it + if (res > 0) + (*it) = (*it).substr(res, std::string::npos); + break; + } + } + if (this->out_buf.empty()) + this->poller->stop_watching_send_events(this); + } +} + +void TCPSocketHandler::close() +{ + TimedEventsManager::instance().cancel("connection_timeout"s + + std::to_string(this->socket)); + if (this->connected || this->connecting) + this->poller->remove_socket_handler(this->get_socket()); + if (this->socket != -1) + { + ::close(this->socket); + this->socket = -1; + } + this->connected = false; + this->connecting = false; +#ifdef CARES_FOUND + this->resolving = false; + this->resolved = false; + this->resolved4 = false; + this->resolved6 = false; + this->free_cares_addrinfo(); + this->cares_error.clear(); +#endif + this->in_buf.clear(); + this->out_buf.clear(); + this->port.clear(); +} + +void TCPSocketHandler::send_data(std::string&& data) +{ +#ifdef BOTAN_FOUND + if (this->use_tls) + this->tls_send(std::move(data)); + else +#endif + this->raw_send(std::move(data)); +} + +void TCPSocketHandler::raw_send(std::string&& data) +{ + if (data.empty()) + return ; + this->out_buf.emplace_back(std::move(data)); + if (this->connected) + this->poller->watch_send_events(this); +} + +void TCPSocketHandler::send_pending_data() +{ + if (this->connected && !this->out_buf.empty()) + this->poller->watch_send_events(this); +} + +bool TCPSocketHandler::is_connected() const +{ + return this->connected; +} + +bool TCPSocketHandler::is_connecting() const +{ +#ifdef CARES_FOUND + return this->connecting || this->resolving; +#else + return this->connecting; +#endif +} + +void* TCPSocketHandler::get_receive_buffer(const size_t) const +{ + return nullptr; +} + +#ifdef BOTAN_FOUND +void TCPSocketHandler::start_tls() +{ + Botan::TLS::Server_Information server_info(this->address, "irc", std::stoul(this->port)); + this->tls = std::make_unique<Botan::TLS::Client>( + std::bind(&TCPSocketHandler::tls_output_fn, this, ph::_1, ph::_2), + std::bind(&TCPSocketHandler::tls_data_cb, this, ph::_1, ph::_2), + std::bind(&TCPSocketHandler::tls_alert_cb, this, ph::_1, ph::_2, ph::_3), + std::bind(&TCPSocketHandler::tls_handshake_cb, this, ph::_1), + session_manager, credential_manager, policy, + rng, server_info, Botan::TLS::Protocol_Version::latest_tls_version()); +} + +void TCPSocketHandler::tls_recv() +{ + static constexpr size_t buf_size = 4096; + char recv_buf[buf_size]; + + const ssize_t size = this->do_recv(recv_buf, buf_size); + if (size > 0) + { + const bool was_active = this->tls->is_active(); + this->tls->received_data(reinterpret_cast<const Botan::byte*>(recv_buf), + static_cast<size_t>(size)); + if (!was_active && this->tls->is_active()) + this->on_tls_activated(); + } +} + +void TCPSocketHandler::tls_send(std::string&& data) +{ + if (this->tls->is_active()) + { + const bool was_active = this->tls->is_active(); + if (!this->pre_buf.empty()) + { + this->tls->send(reinterpret_cast<const Botan::byte*>(this->pre_buf.data()), + this->pre_buf.size()); + this->pre_buf = ""; + } + if (!data.empty()) + this->tls->send(reinterpret_cast<const Botan::byte*>(data.data()), + data.size()); + if (!was_active && this->tls->is_active()) + this->on_tls_activated(); + } + else + this->pre_buf += data; +} + +void TCPSocketHandler::tls_data_cb(const Botan::byte* data, size_t size) +{ + this->in_buf += std::string(reinterpret_cast<const char*>(data), + size); + if (!this->in_buf.empty()) + this->parse_in_buffer(size); +} + +void TCPSocketHandler::tls_output_fn(const Botan::byte* data, size_t size) +{ + this->raw_send(std::string(reinterpret_cast<const char*>(data), size)); +} + +void TCPSocketHandler::tls_alert_cb(Botan::TLS::Alert alert, const Botan::byte*, size_t) +{ + log_debug("tls_alert: " << alert.type_string()); +} + +bool TCPSocketHandler::tls_handshake_cb(const Botan::TLS::Session& session) +{ + log_debug("Handshake with " << session.server_info().hostname() << " complete." + << " Version: " << session.version().to_string() + << " using " << session.ciphersuite().to_string()); + if (!session.session_id().empty()) + log_debug("Session ID " << Botan::hex_encode(session.session_id())); + if (!session.session_ticket().empty()) + log_debug("Session ticket " << Botan::hex_encode(session.session_ticket())); + return true; +} + +void TCPSocketHandler::on_tls_activated() +{ + this->send_data(""); +} + +void Permissive_Credentials_Manager::verify_certificate_chain(const std::string& type, + const std::string& purported_hostname, + const std::vector<Botan::X509_Certificate>&) +{ // TODO: Offer the admin to disallow connection on untrusted + // certificates + log_debug("Checking remote certificate (" << type << ") for hostname " << purported_hostname); +} + +#endif // BOTAN_FOUND + +#ifdef CARES_FOUND + +void TCPSocketHandler::on_hostname4_resolved(int status, struct hostent* hostent) +{ + this->resolved4 = true; + if (status == ARES_SUCCESS) + this->fill_ares_addrinfo4(hostent); + else + this->cares_error = ::ares_strerror(status); + + if (this->resolved4 && this->resolved6) + { + this->resolved = true; + this->resolving = false; + this->connect(); + } +} + +void TCPSocketHandler::on_hostname6_resolved(int status, struct hostent* hostent) +{ + this->resolved6 = true; + if (status == ARES_SUCCESS) + this->fill_ares_addrinfo6(hostent); + else + this->cares_error = ::ares_strerror(status); + + if (this->resolved4 && this->resolved6) + { + this->resolved = true; + this->resolving = false; + this->connect(); + } +} + +void TCPSocketHandler::fill_ares_addrinfo4(const struct hostent* hostent) +{ + struct addrinfo* prev = this->cares_addrinfo; + struct in_addr** address = reinterpret_cast<struct in_addr**>(hostent->h_addr_list); + + while (*address) + { + // Create a new addrinfo list element, and fill it + struct addrinfo* current = new struct addrinfo; + current->ai_flags = 0; + current->ai_family = hostent->h_addrtype; + current->ai_socktype = SOCK_STREAM; + current->ai_protocol = 0; + current->ai_addrlen = sizeof(struct sockaddr_in); + + struct sockaddr_in* addr = new struct sockaddr_in; + addr->sin_family = hostent->h_addrtype; + addr->sin_port = htons(strtoul(this->port.data(), nullptr, 10)); + addr->sin_addr.s_addr = (*address)->s_addr; + + current->ai_addr = reinterpret_cast<struct sockaddr*>(addr); + current->ai_next = nullptr; + current->ai_canonname = nullptr; + + current->ai_next = prev; + this->cares_addrinfo = current; + prev = current; + ++address; + } +} + +void TCPSocketHandler::fill_ares_addrinfo6(const struct hostent* hostent) +{ + struct addrinfo* prev = this->cares_addrinfo; + struct in6_addr** address = reinterpret_cast<struct in6_addr**>(hostent->h_addr_list); + + while (*address) + { + // Create a new addrinfo list element, and fill it + struct addrinfo* current = new struct addrinfo; + current->ai_flags = 0; + current->ai_family = hostent->h_addrtype; + current->ai_socktype = SOCK_STREAM; + current->ai_protocol = 0; + current->ai_addrlen = sizeof(struct sockaddr_in6); + + struct sockaddr_in6* addr = new struct sockaddr_in6; + addr->sin6_family = hostent->h_addrtype; + addr->sin6_port = htons(strtoul(this->port.data(), nullptr, 10)); + ::memcpy(addr->sin6_addr.s6_addr, (*address)->s6_addr, 16); + addr->sin6_flowinfo = 0; + addr->sin6_scope_id = 0; + + current->ai_addr = reinterpret_cast<struct sockaddr*>(addr); + current->ai_next = nullptr; + current->ai_canonname = nullptr; + + current->ai_next = prev; + this->cares_addrinfo = current; + prev = current; + ++address; + } +} + +void TCPSocketHandler::free_cares_addrinfo() +{ + while (this->cares_addrinfo) + { + delete this->cares_addrinfo->ai_addr; + auto next = this->cares_addrinfo->ai_next; + delete this->cares_addrinfo; + this->cares_addrinfo = next; + } +} + +#endif // CARES_FOUND diff --git a/louloulibs/network/tcp_socket_handler.hpp b/louloulibs/network/tcp_socket_handler.hpp new file mode 100644 index 0000000..2b5cd49 --- /dev/null +++ b/louloulibs/network/tcp_socket_handler.hpp @@ -0,0 +1,293 @@ +#ifndef SOCKET_HANDLER_INCLUDED +# define SOCKET_HANDLER_INCLUDED + +#include <network/socket_handler.hpp> + +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <netdb.h> + +#include <memory> +#include <string> +#include <list> + +#include "louloulibs.h" + +#ifdef CARES_FOUND +# include <ares.h> +#endif + +#ifdef BOTAN_FOUND +# include <botan/botan.h> +# include <botan/tls_client.h> + +/** + * A very simple credential manager that accepts any certificate. + */ +class Permissive_Credentials_Manager: public Botan::Credentials_Manager +{ +public: + void verify_certificate_chain(const std::string& type, + const std::string& purported_hostname, + const std::vector<Botan::X509_Certificate>&); +}; +#endif // BOTAN_FOUND + +/** + * An interface, with a series of callbacks that should be implemented in + * subclasses that deal with a socket. These callbacks are called on various events + * (read/write/timeout, etc) when they are notified to a poller + * (select/poll/epoll etc) + */ +class TCPSocketHandler: public SocketHandler +{ +protected: + ~TCPSocketHandler(); + +public: + explicit TCPSocketHandler(std::shared_ptr<Poller> poller); + /** + * Connect to the remote server, and call on_connected() if this + * succeeds. If tls is true, we set use_tls to true and will also call + * start_tls() when the connection succeeds. + */ + void connect(const std::string& address, const std::string& port, const bool tls); + void connect() override final; + /** + * Reads raw data from the socket. And pass it to parse_in_buffer() + * If we are using TLS on this connection, we call tls_recv() + */ + void on_recv() override final; + /** + * Write as much data from out_buf as possible, in the socket. + */ + void on_send() override final; + /** + * Add the given data to out_buf and tell our poller that we want to be + * notified when a send event is ready. + * + * This can be overriden if we want to modify the data before sending + * it. For example if we want to encrypt it. + */ + void send_data(std::string&& data); + /** + * Watch the socket for send events, if our out buffer is not empty. + */ + void send_pending_data(); + /** + * Close the connection, remove us from the poller + */ + void close(); + /** + * Called by a TimedEvent, when the connection did not succeed or fail + * after a given time. + */ + void on_connection_timeout(); + /** + * Called when the connection is successful. + */ + virtual void on_connected() = 0; + /** + * Called when the connection fails. Not when it is closed later, just at + * the connect() call. + */ + virtual void on_connection_failed(const std::string& reason) = 0; + /** + * Called when we detect a disconnection from the remote host. + */ + virtual void on_connection_close(const std::string& error) = 0; + /** + * Handle/consume (some of) the data received so far. The data to handle + * may be in the in_buf buffer, or somewhere else, depending on what + * get_receive_buffer() returned. If some data is used from in_buf, it + * should be truncated, only the unused data should be left untouched. + * + * The size argument is the size of the last chunk of data that was added to the buffer. + */ + virtual void parse_in_buffer(const size_t size) = 0; + bool is_connected() const override final; + bool is_connecting() const; + +#ifdef CARES_FOUND + void on_hostname4_resolved(int status, struct hostent* hostent); + void on_hostname6_resolved(int status, struct hostent* hostent); + + void free_cares_addrinfo(); + + void fill_ares_addrinfo4(const struct hostent* hostent); + void fill_ares_addrinfo6(const struct hostent* hostent); +#endif + +private: + /** + * Initialize the socket with the parameters contained in the given + * addrinfo structure. + */ + void init_socket(const struct addrinfo* rp); + /** + * Reads from the socket into the provided buffer. If an error occurs + * (read returns <= 0), the handling of the error is done here (close the + * connection, log a message, etc). + * + * Returns the value returned by ::recv(), so the buffer should not be + * used if it’s not positive. + */ + ssize_t do_recv(void* recv_buf, const size_t buf_size); + /** + * Reads data from the socket and calls parse_in_buffer with it. + */ + void plain_recv(); + /** + * Mark the given data as ready to be sent, as-is, on the socket, as soon + * as we can. + */ + void raw_send(std::string&& data); + +#ifdef BOTAN_FOUND + /** + * Create the TLS::Client object, with all the callbacks etc. This must be + * called only when we know we are able to send TLS-encrypted data over + * the socket. + */ + void start_tls(); + /** + * An additional step to pass the data into our tls object to decrypt it + * before passing it to parse_in_buffer. + */ + void tls_recv(); + /** + * Pass the data to the tls object in order to encrypt it. The tls object + * will then call raw_send as a callback whenever data as been encrypted + * and can be sent on the socket. + */ + void tls_send(std::string&& data); + /** + * Called by the tls object that some data has been decrypt. We call + * parse_in_buffer() to handle that unencrypted data. + */ + void tls_data_cb(const Botan::byte* data, size_t size); + /** + * Called by the tls object to indicate that some data has been encrypted + * and is now ready to be sent on the socket as is. + */ + void tls_output_fn(const Botan::byte* data, size_t size); + /** + * Called by the tls object to indicate that a TLS alert has been + * received. We don’t use it, we just log some message, at the moment. + */ + void tls_alert_cb(Botan::TLS::Alert alert, const Botan::byte*, size_t); + /** + * Called by the tls object at the end of the TLS handshake. We don't do + * anything here appart from logging the TLS session information. + */ + bool tls_handshake_cb(const Botan::TLS::Session& session); + /** + * Called whenever the tls session goes from inactive to active. This + * means that the handshake has just been successfully done, and we can + * now proceed to send any available data into our tls object. + */ + void on_tls_activated(); +#endif // BOTAN_FOUND + /** + * Where data is added, when we want to send something to the client. + */ + std::list<std::string> out_buf; + /** + * Keep the details of the addrinfo that triggered a EINPROGRESS error when + * connect()ing to it, to reuse it directly when connect() is called + * again. + */ + struct addrinfo addrinfo; + struct sockaddr_in6 ai_addr; + socklen_t ai_addrlen; + +protected: + /** + * Where data read from the socket is added until we can extract a full + * and meaningful “message” from it. + * + * TODO: something more efficient than a string. + */ + std::string in_buf; + /** + * Whether we are using TLS on this connection or not. + */ + bool use_tls; + /** + * Provide a buffer in which data can be directly received. This can be + * used to avoid copying data into in_buf before using it. If no buffer + * needs to be provided, nullptr is returned (the default implementation + * does that), in that case our internal in_buf will be used to save the + * data until it can be used by parse_in_buffer(). + */ + virtual void* get_receive_buffer(const size_t size) const; + /** + * Hostname we are connected/connecting to + */ + std::string address; + /** + * Port we are connected/connecting to + */ + std::string port; + + bool connected; + bool connecting; + +#ifdef CARES_FOUND + bool resolving; + /** + * Whether or not the DNS resolution was successfully done + */ + bool resolved; + bool resolved4; + bool resolved6; + /** + * When using c-ares to resolve the host asynchronously, we need the + * c-ares callback to fill a structure (a struct addrinfo, for + * compatibility with getaddrinfo and the rest of the code that works when + * c-ares is not used) with all returned values (for example an IPv6 and + * an IPv4). The next call of connect() will then try all these values + * (exactly like we do with the result of getaddrinfo) and save the one + * that worked (or returned EINPROGRESS) in the other struct addrinfo (see + * the members addrinfo, ai_addrlen, and ai_addr). + */ + struct addrinfo* cares_addrinfo; + std::string cares_error; +#endif // CARES_FOUND + +private: + TCPSocketHandler(const TCPSocketHandler&) = delete; + TCPSocketHandler(TCPSocketHandler&&) = delete; + TCPSocketHandler& operator=(const TCPSocketHandler&) = delete; + TCPSocketHandler& operator=(TCPSocketHandler&&) = delete; + +#ifdef BOTAN_FOUND + /** + * Botan stuff to manipulate a TLS session. + */ + static Botan::AutoSeeded_RNG rng; + static Permissive_Credentials_Manager credential_manager; + static Botan::TLS::Policy policy; + static Botan::TLS::Session_Manager_In_Memory session_manager; + /** + * We use a unique_ptr because we may not want to create the object at + * all. The Botan::TLS::Client object generates a handshake message as + * soon and calls the output_fn callback with it as soon as it is + * created. Therefore, we do not want to create it if do not intend to do + * send any TLS-encrypted message. We create the object only when needed + * (for example after we have negociated a TLS session using a STARTTLS + * message, or stuf like that). + * + * See start_tls for the method where this object is created. + */ + std::unique_ptr<Botan::TLS::Client> tls; + /** + * An additional buffer to keep data that the user wants to send, but + * cannot because the handshake is not done. + */ + std::string pre_buf; +#endif // BOTAN_FOUND +}; + +#endif // SOCKET_HANDLER_INCLUDED |