ddnet/src/engine/shared/websockets.cpp
def e9bc42a63c Update websockets implementation (fixes #1022)
seems to work with libwebsockets 2.4
2018-02-14 12:30:14 +01:00

277 lines
7 KiB
C++

#if defined(CONF_WEBSOCKETS)
#include <string.h>
#include <stdlib.h>
#include <libwebsockets.h>
#include "base/system.h"
#include "protocol.h"
#include "ringbuffer.h"
#include <arpa/inet.h>
extern "C" {
#include "websockets.h"
// not sure why would anyone need more than one but well...
#define WS_CONTEXTS 4
// ddnet client opens two connections for whatever reason
#define WS_CLIENTS MAX_CLIENTS*2
typedef TStaticRingBuffer<unsigned char, WS_CLIENTS * 4 * 1024, CRingBufferBase::FLAG_RECYCLE> TRecvBuffer;
typedef TStaticRingBuffer<unsigned char, 4 * 1024, CRingBufferBase::FLAG_RECYCLE> TSendBuffer;
typedef struct
{
size_t size;
size_t read;
sockaddr_in addr;
unsigned char data[0];
} websocket_chunk;
struct per_session_data
{
struct lws *wsi;
int port;
sockaddr_in addr;
TSendBuffer send_buffer;
};
struct context_data
{
lws_context *context;
per_session_data *port_map[WS_CLIENTS];
TRecvBuffer recv_buffer;
int last_used_port;
};
static int receive_chunk(context_data *ctx_data, struct per_session_data *pss, void *in, size_t len)
{
websocket_chunk *chunk = (websocket_chunk *)ctx_data->recv_buffer.Allocate(len + sizeof(websocket_chunk));
if(chunk == 0)
return 1;
chunk->size = len;
chunk->read = 0;
memcpy(&chunk->addr, &pss->addr, sizeof(sockaddr_in));
memcpy(&chunk->data[0], in, len);
return 0;
}
static int websocket_callback(struct lws *wsi, enum lws_callback_reasons reason, void *user, void *in, size_t len)
{
struct per_session_data *pss = (struct per_session_data *)user;
lws_context *context = lws_get_context(wsi);
context_data *ctx_data = (context_data *)lws_context_user(context);
switch(reason)
{
case LWS_CALLBACK_ESTABLISHED:
{
int port = -1;
for(int i = 0; i < WS_CLIENTS; i++)
{
int j = (ctx_data->last_used_port + i + 1) % WS_CLIENTS;
if(ctx_data->port_map[j] == NULL)
{
port = j;
break;
}
}
if(port == -1)
{
dbg_msg("websockets", "no free ports, dropping");
pss->port = -1;
return -1;
}
ctx_data->last_used_port = port;
pss->wsi = wsi;
int fd = lws_get_socket_fd(wsi);
socklen_t addr_size = sizeof(pss->addr);
getpeername(fd, (struct sockaddr *)&pss->addr, &addr_size);
int orig_port = ntohs(pss->addr.sin_port);
pss->addr.sin_port = htons(port);
pss->send_buffer.Init();
pss->port = port;
ctx_data->port_map[port] = pss;
char addr_str[NETADDR_MAXSTRSIZE];
inet_ntop(AF_INET, &pss->addr.sin_addr, addr_str, sizeof(addr_str));
dbg_msg("websockets", "connection established with %s:%d , assigned fake port %d", addr_str, orig_port, port);
}
break;
case LWS_CALLBACK_CLOSED:
{
dbg_msg("websockets", "connection with fake port %d closed", pss->port);
if (pss->port > -1) {
unsigned char close_packet[] = { 0x10, 0x0e, 0x00, 0x04 };
receive_chunk(ctx_data, pss, &close_packet, sizeof(close_packet));
pss->wsi = 0;
ctx_data->port_map[pss->port] = NULL;
}
}
break;
case LWS_CALLBACK_SERVER_WRITEABLE:
{
websocket_chunk *chunk = (websocket_chunk *)pss->send_buffer.First();
if(chunk == NULL)
break;
int len = chunk->size - chunk->read;
int n = lws_write(wsi, &chunk->data[LWS_SEND_BUFFER_PRE_PADDING + chunk->read], chunk->size - chunk->read, LWS_WRITE_BINARY);
if(n < 0)
return 1;
if(n < len)
{
chunk->read += n;
lws_callback_on_writable(wsi);
break;
}
pss->send_buffer.PopFirst();
lws_callback_on_writable(wsi);
}
break;
case LWS_CALLBACK_RECEIVE:
if(pss->port == -1)
return -1;
if(!receive_chunk(ctx_data, pss, in, len))
return 1;
break;
default:
break;
}
return 0;
}
static struct lws_protocols protocols[] = { {
"binary", /* name */
websocket_callback, /* callback */
sizeof(struct per_session_data) /* per_session_data_size */
},
{
NULL, NULL, 0 /* End of list */
} };
static context_data contexts[WS_CONTEXTS];
int websocket_create(const char *addr, int port)
{
struct lws_context_creation_info info;
memset(&info, 0, sizeof(info));
info.port = port;
info.iface = addr;
info.protocols = protocols;
info.gid = -1;
info.uid = -1;
// find free context
int first_free = -1;
for(int i = 0; i < WS_CONTEXTS; i++)
{
if(contexts[i].context == NULL)
{
first_free = i;
break;
}
}
if(first_free == -1)
return -1;
context_data *ctx_data = &contexts[first_free];
info.user = (void *)ctx_data;
ctx_data->context = lws_create_context(&info);
if(ctx_data->context == NULL)
{
return -1;
}
memset(ctx_data->port_map, 0, sizeof(ctx_data->port_map));
ctx_data->recv_buffer.Init();
ctx_data->last_used_port = 0;
return first_free;
}
int websocket_destroy(int socket)
{
lws_context *context = contexts[socket].context;
if(context == NULL)
return -1;
lws_context_destroy(context);
contexts[socket].context = NULL;
return 0;
}
int websocket_recv(int socket, unsigned char *data, size_t maxsize, struct sockaddr_in *sockaddrbuf, size_t fromLen)
{
lws_context *context = contexts[socket].context;
if(context == NULL)
return -1;
int n = lws_service(context, 0);
if(n < 0)
return n;
context_data *ctx_data = (context_data *)lws_context_user(context);
websocket_chunk *chunk = (websocket_chunk *)ctx_data->recv_buffer.First();
if(chunk == 0)
return 0;
if(maxsize >= chunk->size - chunk->read)
{
int len = chunk->size - chunk->read;
memcpy(data, &chunk->data[chunk->read], len);
memcpy(sockaddrbuf, &chunk->addr, fromLen);
ctx_data->recv_buffer.PopFirst();
return len;
}
else
{
memcpy(data, &chunk->data[chunk->read], maxsize);
memcpy(sockaddrbuf, &chunk->addr, fromLen);
chunk->read += maxsize;
return maxsize;
}
}
int websocket_send(int socket, const unsigned char *data, size_t size, int port)
{
lws_context *context = contexts[socket].context;
if(context == NULL)
return -1;
context_data *ctx_data = (context_data *)lws_context_user(context);
struct per_session_data *pss = ctx_data->port_map[port];
if(pss == NULL)
return -1;
websocket_chunk *chunk = (websocket_chunk *)pss->send_buffer.Allocate(size + sizeof(websocket_chunk) + LWS_SEND_BUFFER_PRE_PADDING + LWS_SEND_BUFFER_POST_PADDING);
if(chunk == NULL)
return -1;
chunk->size = size;
chunk->read = 0;
memcpy(&chunk->addr, &pss->addr, sizeof(sockaddr_in));
memcpy(&chunk->data[LWS_SEND_BUFFER_PRE_PADDING], data, size);
lws_callback_on_writable(pss->wsi);
return size;
}
int websocket_fd_set(int socket, fd_set *set)
{
lws_context *context = contexts[socket].context;
if(context == NULL)
return -1;
context_data *ctx_data = (context_data *)lws_context_user(context);
int max = 0;
for(int i = 0; i < WS_CLIENTS; i++)
{
per_session_data *pss = ctx_data->port_map[i];
if(pss == NULL)
continue;
int fd = lws_get_socket_fd(pss->wsi);
if(fd > max)
max = fd;
FD_SET(fd, set);
}
return max;
}
}
#endif