uhub/src/core/link.c

509 lines
11 KiB
C

/*
* uhub - A tiny ADC p2p connection hub
* Copyright (C) 2007-2013, Jan Vidar Krey
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#include "uhub.h"
#ifdef LINK_SUPPORT
static int link_send_support(struct hub_link* link);
static void link_net_event(struct net_connection* con, int event, void *arg)
{
LOG_INFO("link_net_event(), event=%d", event);
struct hub_link* link = (struct hub_link*) arg;
struct hub_info* hub = link->hub;
int ret = 0;
if (event == NET_EVENT_TIMEOUT)
{
LOG_DEBUG("Hub link timeout!");
}
if (event & NET_EVENT_READ)
{
ret = link_handle_read(link);
if (ret < 0)
{
link_disconnect(link);
return;
}
}
if (event & NET_EVENT_WRITE)
{
ret = link_handle_write(link);
if (ret < 0)
{
link_disconnect(link);
return;
}
}
}
void link_disconnect(struct hub_link* link)
{
if (link->connection)
net_con_close(link->connection);
link->connection = NULL;
ioq_send_destroy(link->send_queue);
ioq_recv_destroy(link->recv_queue);
link->send_queue = NULL;
link->recv_queue = NULL;
// FIXME: Notify hub and disconnect users!
hub_free(link);
}
static struct hub_link* link_create_internal(struct hub_info* hub)
{
struct hub_link* link = NULL;
LOG_DEBUG("link_create_internal(), hub=%p");
link = (struct hub_link*) hub_malloc_zero(sizeof(struct hub_link));
if (link == NULL)
return NULL; /* OOM */
link->send_queue = ioq_send_create();
link->recv_queue = ioq_recv_create();
link->hub = hub;
link->state = state_protocol;
return link;
}
struct hub_link* link_create(struct hub_info* hub, struct net_connection* con, struct ip_addr_encap* addr)
{
struct hub_link* link = link_create_internal(hub);
link->connection = con;
net_con_reinitialize(link->connection, link_net_event, link, NET_EVENT_READ);
link->mode = link_mode_server;
return link;
}
static void link_connect_callback(struct net_connect_handle* handle, enum net_connect_status status, struct net_connection* con, void* ptr)
{
struct hub_link* link = (struct hub_link*) ptr;
link->connect_job = NULL;
LOG_DEBUG("link_connect_callback()");
switch (status)
{
case net_connect_status_ok:
link->connection = con;
net_con_reinitialize(link->connection, link_net_event, link, NET_EVENT_READ);
// FIXME: send handshake here
link_send_support(link);
break;
case net_connect_status_host_not_found:
case net_connect_status_no_address:
case net_connect_status_dns_error:
case net_connect_status_refused:
case net_connect_status_unreachable:
case net_connect_status_timeout:
case net_connect_status_socket_error:
// FIXME: Unable to connect - start timer and re-try connection establishment!
break;
}
}
struct link_address
{
char host[256];
uint16_t port;
};
static int link_parse_address(const char* arg, struct link_address* addr)
{
int port;
char* split;
memset(addr, 0, sizeof(struct link_address));
/* Split hostname and port (if possible) */
split = strrchr(arg, ':');
if (split == 0 || strlen(split) < 2 || strlen(split) > 6)
return 0;
/* Ensure port number is valid */
port = strtol(split+1, NULL, 10);
if (port <= 0 || port > 65535)
return 0;
memcpy(addr->host, arg, &split[0] - &arg[0]);
addr->port = port;
return 1;
}
struct hub_link* link_connect_uri(struct hub_info* hub, const char* address)
{
struct link_address link_address;
if (!link_parse_address(address, &link_address))
{
LOG_INFO("Invalid master hub link address");
return NULL;
}
return link_connect(hub, link_address.host, link_address.port);
}
struct hub_link* link_connect(struct hub_info* hub, const char* address, uint16_t port)
{
struct hub_link* link = link_create_internal(hub);
LOG_DEBUG("Connecting to master link at %s:%d...", address, port);
link->mode = link_mode_client;
link->connect_job = net_con_connect(address, port, link_connect_callback, link);
if (!link->connect_job)
{
// FIXME: Immediate failure!
LOG_DEBUG("Error connecting to master hub link.");
link_disconnect(link);
return NULL;
}
return link;
}
static int link_net_io_want_read(struct hub_link* link)
{
net_con_update(link->connection, NET_EVENT_READ);
}
static int link_net_io_want_write(struct hub_link* link)
{
net_con_update(link->connection, NET_EVENT_READ | NET_EVENT_WRITE);
}
int link_handle_write(struct hub_link* link)
{
int ret = 0;
while (ioq_send_get_bytes(link->send_queue))
{
ret = ioq_send_send(link->send_queue, link->connection);
if (ret <= 0)
break;
}
if (ret < 0)
return -1; // FIXME! Extract socket error!
if (ioq_send_get_bytes(link->send_queue))
link_net_io_want_write(link);
else
link_net_io_want_read(link);
return 0;
}
int link_send_message(struct hub_link* link, struct adc_message* msg)
{
#ifdef DEBUG_SENDQ
char* data = strndup(msg->cache, msg->length-1);
LOG_PROTO("[link] send %p: \"%s\"", link, data);
free(data);
#endif
if (!link->connection)
return -1;
uhub_assert(msg->cache && *msg->cache);
if (ioq_send_is_empty(link->send_queue) /*&& !user_flag_get(user, flag_pipeline)*/)
{
/* Perform oportunistic write */
ioq_send_add(link->send_queue, msg);
link_handle_write(link);
}
else
{
// if (check_send_queue(hub, user, msg) >= 0)
// {
ioq_send_add(link->send_queue, msg);
// if (!user_flag_get(user, flag_pipeline))
link_net_io_want_write(link);
}
return 0;
}
static int link_send_support(struct hub_link* link)
{
int ret;
struct adc_message* msg = adc_msg_construct(ADC_CMD_LSUP, 6 + strlen(ADC_PROTO_LINK_SUPPORT));
adc_msg_add_argument(msg, ADC_PROTO_LINK_SUPPORT);
ret = link_send_message(link, msg);
adc_msg_free(msg);
return ret;
}
static int link_send_welcome(struct hub_link* link)
{
int ret;
struct adc_message* info = adc_msg_construct(ADC_CMD_LINF, 128);
if (!info)
return -1;
adc_msg_add_named_argument(info, ADC_INF_FLAG_CLIENT_TYPE, ADC_CLIENT_TYPE_HUB);
adc_msg_add_named_argument_string(info, ADC_INF_FLAG_USER_AGENT, PRODUCT_STRING);
adc_msg_add_named_argument_string(info, ADC_INF_FLAG_NICK, link->hub->config->hub_name);
adc_msg_add_named_argument_string(info, ADC_INF_FLAG_DESCRIPTION, link->hub->config->hub_description);
ret = link_send_message(link, info);
link->state = state_normal;
}
static int link_send_auth_response(struct hub_link* link, const char* challenge)
{
int ret;
struct adc_message* msg = adc_msg_construct(ADC_CMD_LPAS, 128);
// FIXME: Solve challenge.
ret = link_send_message(link, msg);
adc_msg_free(msg);
return ret;
}
static int link_send_auth_request(struct hub_link* link)
{
int ret;
struct adc_message* msg = adc_msg_construct(ADC_CMD_LGPA, 128);
// FIXME: Create challenge.
char buf[64];
uint64_t tiger_res[3];
static char tiger_buf[MAX_CID_LEN+1];
LOG_DEBUG("link_send_auth_request");
// FIXME: Generate a better nonce scheme.
snprintf(buf, 64, "%p%d", link, (int) net_con_get_sd(link->connection));
tiger((uint64_t*) buf, strlen(buf), (uint64_t*) tiger_res);
base32_encode((unsigned char*) tiger_res, TIGERSIZE, tiger_buf);
tiger_buf[MAX_CID_LEN] = 0;
// Add nonce to message
adc_msg_add_argument(msg, (const char*) tiger_buf);
ret = link_send_message(link, msg);
adc_msg_free(msg);
return ret;
}
static int link_handle_support(struct hub_link* link, struct adc_message* msg)
{
int ret = 0;
LOG_DEBUG("link_handle_support");
if (link->mode == link_mode_server)
{
if (link->state == state_protocol)
{
ret = link_send_support(link);
if (ret == 0)
ret = link_send_auth_request(link);
link->state = state_verify;
}
}
return ret;
}
static int link_handle_auth_request(struct hub_link* link, struct adc_message* msg)
{
char* challenge;
int ret = -1;
LOG_DEBUG("link_handle_auth_request");
if (link->state == state_verify)
return -1;
if (link->mode == link_mode_client)
{
challenge = adc_msg_get_argument(msg, 0);
ret = link_send_auth_response(link, challenge);
hub_free(challenge);
}
return ret;
}
static int link_handle_auth_response(struct hub_link* link, struct adc_message* msg)
{
LOG_DEBUG("link_handle_auth_response. link_state=%d", (int) link->state);
if (link->state != state_verify)
return -1;
LOG_DEBUG("State is not verify!");
if (link->mode == link_mode_server)
{
// Check authentication data
// FIXME: Can involve plug-ins at this point.
return link_send_welcome(link);
}
else
{
LOG_DEBUG("Ignoring auth response - We're client mode!");
}
return -1;
}
static int link_handle_link_info(struct hub_link* link, struct adc_message* msg)
{
LOG_DEBUG("link_handle_link_info");
return 0;
}
static int link_handle_status(struct hub_link* link, struct adc_message* msg)
{
LOG_DEBUG("link_handle_status");
return -1;
}
static int link_handle_message(struct hub_link* link, const char* message, size_t length)
{
int ret = 0;
struct adc_message* cmd = 0;
LOG_INFO("link_handle_message(): %s (%d)", message, (int) length);
// FIXME: is this needed?
if (link->state == state_cleanup || link->state == state_disconnected)
return -1;
cmd = adc_msg_parse(message, length);
if (!cmd)
{
LOG_DEBUG("Unable to parse hub-link message");
return -1;
}
// if (
switch (cmd->cmd)
{
case ADC_CMD_LSUP:
ret = link_handle_support(link, cmd);
break;
case ADC_CMD_LPAS:
ret = link_handle_auth_response(link, cmd);
break;
case ADC_CMD_LGPA:
ret = link_handle_auth_request(link, cmd);
break;
case ADC_CMD_LINF:
ret = link_handle_link_info(link, cmd);
break;
case ADC_CMD_LSTA:
ret = link_handle_status(link, cmd);
break;
}
adc_msg_free(cmd);
return ret;
}
static int link_read_message(struct hub_link* link)
{
char* lastPos = 0;
char* pos = 0;
char* start = link->recv_queue->buf;
size_t remaining = link->recv_queue->size;
while ((pos = memchr(start, '\n', remaining)))
{
lastPos = pos+1;
pos[0] = '\0';
if (link->flags & 1)
{
/* FIXME Unset maxbuf flag */
link->flags = 0;
}
else
{
if (link_handle_message(link, start, (pos - start)) == -1)
{
return -1;
}
}
pos[0] = '\n'; /* FIXME: not needed */
pos ++;
remaining -= (pos - start);
start = pos;
}
ioq_recv_consume(link->recv_queue, (start - link->recv_queue->buf));
return 0;
}
int link_handle_read(struct hub_link* link)
{
int ret = 0;
while (1)
{
switch (ioq_recv_read(link->recv_queue, link->connection))
{
case ioq_recv_ok:
if (link_read_message(link) < 0)
{
// FIXME: propagate protocol error?
return -1;
}
// Parse messages then call again
break;
case ioq_recv_later:
return 0;
case ioq_recv_full:
link->flags = 1; // FIXME: MAXBUF
ioq_recv_set(link->recv_queue, 0, 0);
break;
case ioq_recv_error:
return -1; // FIXME: it would be good to signal type of socket error
}
}
return 0;
}
#endif /* LINK_SUPPORT */