From 3f7b086e249e394427b896c93ae0a6749b755f41 Mon Sep 17 00:00:00 2001
From: Ian Gulliver <flamingcow@gmail.com>
Date: Thu, 5 Feb 2015 16:36:25 +0000
Subject: [PATCH] Main loop, epoll handling

---
 Makefile       |  2 +-
 auth-server.cc | 32 ++++++++++++++----
 crypto.cc      | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++
 crypto.h       | 31 +++++++++++++++++
 4 files changed, 150 insertions(+), 7 deletions(-)

diff --git a/Makefile b/Makefile
index c639b17..5020223 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 all: auth-server gen-key gen-keypair
 
 %.o: %.cc
-	g++ -c -o $@ $<
+	g++ -std=c++11 -c -o $@ $<
 
 auth-server: auth-server.o crypto.o
 	g++ -o auth-server auth-server.o crypto.o nacl/build/instance1/lib/amd64/randombytes.o nacl/build/instance1/lib/amd64/libnacl.a
diff --git a/auth-server.cc b/auth-server.cc
index 4ffa1cb..5453578 100644
--- a/auth-server.cc
+++ b/auth-server.cc
@@ -1,14 +1,34 @@
 #include <iostream>
 
-#include "nacl/build/instance1/include/amd64/crypto_box.h"
+#include <netinet/in.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include "crypto.h"
 
 int main() {
-	std::string pk;
-	std::string sk;
+	int fd = socket(PF_INET6, SOCK_STREAM, 0);
 
-	pk = crypto_box_keypair(&sk);
+  int optval = 1;
+  setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof(optval));
 
-	std::cout << pk.size() << std::endl;
+	struct sockaddr_in6 server_addr = {0};
+ 	server_addr.sin6_family = AF_INET6;
+ 	server_addr.sin6_addr = in6addr_any;
+ 	server_addr.sin6_port = htons(4990);
 
-	return 0;
+	if (bind(fd, (struct sockaddr*) &server_addr, sizeof(server_addr))) {
+		perror("bind");
+		return 1;
+	}
+
+	if (listen(fd, 256)) {
+		perror("listen");
+		return 1;
+	}
+
+	CryptoPubServer server(fd, "abcde");
+	server.Loop();
 }
diff --git a/crypto.cc b/crypto.cc
index a0dc488..dabaecd 100644
--- a/crypto.cc
+++ b/crypto.cc
@@ -1,9 +1,25 @@
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <iostream>
+
 #include "crypto.h"
 
 #include "nacl/build/instance1/include/amd64/crypto_box.h"
 #include "nacl/build/instance1/include/amd64/crypto_secretbox.h"
 #include "nacl/build/instance1/include/amd64/randombytes.h"
 
+CryptoBase::CryptoBase(const int fd)
+	: fd_(fd) {}
+
+CryptoBase::~CryptoBase() {
+	if (close(fd_)) {
+		perror("close");
+	}
+}
+
 std::string CryptoBase::BinToHex(const std::string& bin) {
 	static const char *hex = "0123456789ABCDEF";
 	std::string ret;
@@ -25,3 +41,79 @@ void CryptoBase::GenKey(std::string* key) {
 void CryptoBase::GenKeyPair(std::string* secret_key, std::string* public_key) {
 	*public_key = crypto_box_keypair(secret_key);
 }
+
+
+CryptoPubServer::CryptoPubServer(const int fd, const std::string secret_key)
+	: CryptoBase(fd),
+	  secret_key_(secret_key),
+    epoll_fd_(epoll_create(256)) {
+	epoll_event event = {
+		.events = EPOLLIN,
+		.data = {
+			.ptr = this,
+		},
+	};
+	epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, fd, &event);
+}
+
+CryptoPubServer::~CryptoPubServer() {
+	if (close(epoll_fd_)) {
+		perror("close");
+	}
+}
+
+int CryptoPubServer::OnReadable() {
+	struct sockaddr_in6 client;
+	socklen_t client_len = sizeof(client);
+	auto client_fd = accept(fd_, (struct sockaddr*) &client, &client_len);
+	if (client_fd == -1) {
+		perror("accept");
+		return -1;
+	}
+
+	char buf[128];
+	inet_ntop(AF_INET6, &client.sin6_addr, buf, 128);
+	std::cerr << "New connection from [" << buf << "]:" << ntohs(client.sin6_port) << std::endl;
+	auto peer = new CryptoPubPeer(client_fd, secret_key_);
+	
+	epoll_event event = {
+		.events = EPOLLIN,
+		.data = {
+			.ptr = peer,
+		},
+	};
+	epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, client_fd, &event);
+
+	return -1;
+}
+
+void CryptoPubServer::Loop() {
+	while (1) {
+		epoll_event events[10];
+		auto num_events = epoll_wait(epoll_fd_, events, 10, -1);
+		for (int i = 0; i < num_events; i++) {
+			if (events[i].events & EPOLLIN) {
+				auto obj = (CryptoBase*) events[i].data.ptr;
+				auto fd = obj->OnReadable();
+				if (fd >= 0) {
+					epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, &events[i]);
+				}
+			}
+		}
+	}
+}
+
+
+CryptoPubPeer::CryptoPubPeer(const int fd, const std::string secret_key)
+	: CryptoBase(fd),
+	  secret_key_(secret_key) {
+}
+
+int CryptoPubPeer::OnReadable() {
+	char buf[128];
+	if (read(fd_, buf, 128) == 0) {
+		auto fd = fd_;
+		delete this;
+		return fd;
+	}
+}
diff --git a/crypto.h b/crypto.h
index 6df3b98..9e11487 100644
--- a/crypto.h
+++ b/crypto.h
@@ -1,8 +1,39 @@
+#include <sys/epoll.h>
+
 #include <string>
 
 class CryptoBase {
 	public:
+		CryptoBase(const int fd);
+		virtual ~CryptoBase();
+
 		static std::string BinToHex(const std::string& bin);
 		static void GenKey(std::string* key);
 		static void GenKeyPair(std::string* secret_key, std::string* public_key);
+		virtual int OnReadable() = 0;
+
+	protected:
+		const int fd_;
+};
+
+class CryptoPubPeer : public CryptoBase {
+	public:
+		CryptoPubPeer(const int fd, const std::string secret_key);
+		int OnReadable();
+
+	private:
+		const std::string secret_key_;
+		const std::string ephemeral_secret_key_;
+};
+
+class CryptoPubServer : public CryptoBase {
+	public:
+		CryptoPubServer(const int fd, const std::string secret_key);
+		~CryptoPubServer();
+		int OnReadable();
+		void Loop();
+
+	private:
+		const std::string secret_key_;
+		const int epoll_fd_;
 };