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/*
* TLS echo server using BSD sockets
* (C) 2014 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include "cli.h"
#if defined(BOTAN_HAS_TLS) && defined(BOTAN_TARGET_OS_HAS_SOCKETS)
#include <botan/tls_server.h>
#include <botan/hex.h>
#include "credentials.h"
#include <list>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#if !defined(MSG_NOSIGNAL)
#define MSG_NOSIGNAL 0
#endif
namespace Botan_CLI {
class TLS_Server final : public Command
{
public:
TLS_Server() : Command("tls_server cert key --port=443 --type=tcp") {}
void go() override
{
const std::string server_crt = get_arg("cert");
const std::string server_key = get_arg("key");
const int port = get_arg_sz("port");
const std::string transport = get_arg("type");
if(transport != "tcp" && transport != "udp")
throw CLI_Usage_Error("Invalid transport type '" + transport + "' for TLS");
const bool is_tcp = (transport == "tcp");
Botan::TLS::Policy policy; // TODO read policy from file
Botan::TLS::Session_Manager_In_Memory session_manager(rng()); // TODO sqlite3
Basic_Credentials_Manager creds(rng(), server_crt, server_key);
auto protocol_chooser = [](const std::vector<std::string>& protocols) -> std::string {
for(size_t i = 0; i != protocols.size(); ++i)
std::cout << "Client offered protocol " << i << " = " << protocols[i] << std::endl;
return "echo/1.0"; // too bad
};
output() << "Listening for new connections on " << transport << " port " << port << std::endl;
int server_fd = make_server_socket(is_tcp, port);
while(true)
{
int fd;
if(is_tcp)
fd = ::accept(server_fd, nullptr, nullptr);
else
{
struct sockaddr_in from;
socklen_t from_len = sizeof(sockaddr_in);
if(::recvfrom(server_fd, nullptr, 0, MSG_PEEK,
(struct sockaddr*)&from, &from_len) != 0)
throw CLI_Error("Could not peek next packet");
if(::connect(server_fd, (struct sockaddr*)&from, from_len) != 0)
throw CLI_Error("Could not connect UDP socket");
fd = server_fd;
}
using namespace std::placeholders;
auto socket_write = is_tcp ? std::bind(&stream_socket_write, fd, _1, _2) :
std::bind(&dgram_socket_write, fd, _1, _2);
std::string s;
std::list<std::string> pending_output;
auto proc_fn = [&](const uint8_t input[], size_t input_len)
{
for(size_t i = 0; i != input_len; ++i)
{
const char c = static_cast<char>(input[i]);
s += c;
if(c == '\n')
{
pending_output.push_back(s);
s.clear();
}
}
};
Botan::TLS::Server server(socket_write,
proc_fn,
std::bind(&TLS_Server::alert_received, this, _1, _2, _3),
std::bind(&TLS_Server::handshake_complete, this, _1),
session_manager,
creds,
policy,
rng(),
protocol_chooser,
!is_tcp);
while(!server.is_closed())
{
uint8_t buf[4*1024] = { 0 };
ssize_t got = ::read(fd, buf, sizeof(buf));
if(got == -1)
{
std::cout << "Error in socket read - " << strerror(errno) << std::endl;
break;
}
if(got == 0)
{
std::cout << "EOF on socket" << std::endl;
break;
}
server.received_data(buf, got);
while(server.is_active() && !pending_output.empty())
{
std::string output = pending_output.front();
pending_output.pop_front();
server.send(output);
if(output == "quit\n")
server.close();
}
}
if(is_tcp)
::close(fd);
}
}
private:
int make_server_socket(bool is_tcp, uint16_t port)
{
const int type = is_tcp ? SOCK_STREAM : SOCK_DGRAM;
int fd = ::socket(PF_INET, type, 0);
if(fd == -1)
throw CLI_Error("Unable to acquire socket");
sockaddr_in socket_info;
::memset(&socket_info, 0, sizeof(socket_info));
socket_info.sin_family = AF_INET;
socket_info.sin_port = htons(port);
// FIXME: support limiting listeners
socket_info.sin_addr.s_addr = INADDR_ANY;
if(::bind(fd, (sockaddr*)&socket_info, sizeof(struct sockaddr)) != 0)
{
::close(fd);
throw CLI_Error("server bind failed");
}
if(is_tcp)
{
if(::listen(fd, 100) != 0)
{
::close(fd);
throw CLI_Error("listen failed");
}
}
return fd;
}
bool handshake_complete(const Botan::TLS::Session& session)
{
std::cout << "Handshake complete, " << session.version().to_string()
<< " using " << session.ciphersuite().to_string() << std::endl;
if(!session.session_id().empty())
std::cout << "Session ID " << Botan::hex_encode(session.session_id()) << std::endl;
if(!session.session_ticket().empty())
std::cout << "Session ticket " << Botan::hex_encode(session.session_ticket()) << std::endl;
return true;
}
static void dgram_socket_write(int sockfd, const uint8_t buf[], size_t length)
{
ssize_t sent = ::send(sockfd, buf, length, MSG_NOSIGNAL);
if(sent == -1)
std::cout << "Error writing to socket - " << strerror(errno) << std::endl;
else if(sent != static_cast<ssize_t>(length))
std::cout << "Packet of length " << length << " truncated to " << sent << std::endl;
}
static void stream_socket_write(int sockfd, const uint8_t buf[], size_t length)
{
while(length)
{
ssize_t sent = ::send(sockfd, buf, length, MSG_NOSIGNAL);
if(sent == -1)
{
if(errno == EINTR)
sent = 0;
else
throw CLI_Error("Socket write failed");
}
buf += sent;
length -= sent;
}
}
void alert_received(Botan::TLS::Alert alert, const uint8_t[], size_t)
{
std::cout << "Alert: " << alert.type_string() << std::endl;
}
};
BOTAN_REGISTER_COMMAND("tls_server", TLS_Server);
}
#endif
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