/**
* aim_gettlv16 - Retrieve the Nth TLV in chain as a 16bit integer.
* @list: Source TLV chain
* @type: TLV type to search for
* @nth: Index of TLV to return
*
* Same as aim_gettlv(), except that the return value is a
* 16bit integer instead of an aim_tlv_t.
*
*/
faim_internal fu16_t aim_gettlv16(aim_tlvlist_t *list, const fu16_t t, const int n)
{
aim_tlv_t *tlv;
if (!(tlv = aim_gettlv(list, t, n)))
return 0; /* erm */
return aimutil_get16(tlv->value);
}
guint16 byte_stream_get16(ByteStream *bs)
{
if (byte_stream_empty(bs) < 2)
return 0; /* XXX throw an exception */
bs->offset += 2;
return aimutil_get16(bs->data + bs->offset - 2);
}
faim_internal fu16_t aimbs_get16(aim_bstream_t *bs)
{
if (aim_bstream_empty(bs) < 2)
return 0; /* XXX throw an exception */
bs->offset += 2;
return aimutil_get16(bs->data + bs->offset - 2);
}
guint16 aimbs_get16(aim_bstream_t *bs)
{
if (aim_bstream_empty(bs) < 2) {
return 0; /* XXX throw an exception */
}
bs->offset += 2;
return aimutil_get16(bs->data + bs->offset - 2);
}
/**
* This should be used to read ODC and OFT framing info. It should
* NOT be used to read the payload sent across the connection (IMs,
* file data, etc), and it should NOT be used to read proxy negotiation
* headers.
*
* Unlike flap_connection_recv_cb(), this only reads one frame at a
* time. This is done so that the watcher can be changed during the
* handling of the frame. If the watcher is changed then this
* function will not read in any more data. This happens when
* reading the payload of a direct IM frame, or when we're
* receiving a file from the remote user. Once the data has been
* read, the watcher will be switched back to this function to
* continue reading the next frame.
*/
void
peer_connection_recv_cb(gpointer data, gint source, PurpleInputCondition cond)
{
PeerConnection *conn;
gssize read;
conn = data;
/* Start reading a new ODC/OFT frame */
if (conn->buffer_incoming.data == NULL)
{
/* Read the first 6 bytes (magic string and frame length) */
read = recv(conn->fd, conn->header + conn->header_received,
6 - conn->header_received, 0);
/* Check if the remote user closed the connection */
if (read == 0)
{
peer_connection_destroy(conn, OSCAR_DISCONNECT_REMOTE_CLOSED, NULL);
return;
}
/* If there was an error then close the connection */
if (read < 0)
{
if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
/* No worries */
return;
peer_connection_destroy(conn,
OSCAR_DISCONNECT_LOST_CONNECTION, g_strerror(errno));
return;
}
conn->lastactivity = time(NULL);
/* If we don't even have the first 6 bytes then do nothing */
conn->header_received += read;
if (conn->header_received < 6)
return;
/* All ODC/OFT frames must start with a magic string */
if (memcmp(conn->magic, conn->header, 4))
{
purple_debug_warning("oscar", "Expecting magic string to "
"be %c%c%c%c but received magic string %c%c%c%c. "
"Closing connection.\n",
conn->magic[0], conn->magic[1], conn->magic[2],
conn->magic[3], conn->header[0], conn->header[1],
conn->header[2], conn->header[3]);
peer_connection_destroy(conn, OSCAR_DISCONNECT_INVALID_DATA, NULL);
return;
}
/* Initialize a new temporary ByteStream for incoming data */
conn->buffer_incoming.len = aimutil_get16(&conn->header[4]) - 6;
conn->buffer_incoming.data = g_new(guint8, conn->buffer_incoming.len);
conn->buffer_incoming.offset = 0;
}
/* Read data into the temporary buffer until it is complete */
read = recv(conn->fd,
&conn->buffer_incoming.data[conn->buffer_incoming.offset],
conn->buffer_incoming.len - conn->buffer_incoming.offset,
0);
/* Check if the remote user closed the connection */
if (read == 0)
{
peer_connection_destroy(conn, OSCAR_DISCONNECT_REMOTE_CLOSED, NULL);
return;
}
if (read < 0)
{
if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
/* No worries */
return;
peer_connection_destroy(conn,
OSCAR_DISCONNECT_LOST_CONNECTION, g_strerror(errno));
return;
}
conn->lastactivity = time(NULL);
conn->buffer_incoming.offset += read;
if (conn->buffer_incoming.offset < conn->buffer_incoming.len)
/* Waiting for more data to arrive */
return;
/* We have a complete ODC/OFT frame! Handle it and continue reading */
byte_stream_rewind(&conn->buffer_incoming);
if (conn->type == OSCAR_CAPABILITY_DIRECTIM)
{
peer_odc_recv_frame(conn, &conn->buffer_incoming);
}
else if (conn->type == OSCAR_CAPABILITY_SENDFILE)
{
peer_oft_recv_frame(conn, &conn->buffer_incoming);
}
g_free(conn->buffer_incoming.data);
conn->buffer_incoming.data = NULL;
conn->header_received = 0;
}
static void
peer_proxy_connection_recv_cb(gpointer data, gint source, PurpleInputCondition cond)
{
PeerConnection *conn;
gssize read;
ProxyFrame *frame;
conn = data;
frame = conn->frame;
/* Start reading a new proxy frame */
if (frame == NULL)
{
/* Read the first 12 bytes (frame length and header) */
read = recv(conn->fd, conn->proxy_header + conn->proxy_header_received,
12 - conn->proxy_header_received, 0);
/* Check if the proxy server closed the connection */
if (read == 0)
{
purple_debug_info("oscar", "Peer proxy server closed connection\n");
peer_connection_trynext(conn);
return;
}
/* If there was an error then close the connection */
if (read < 0)
{
if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
/* No worries */
return;
purple_debug_info("oscar", "Lost connection with peer proxy server\n");
peer_connection_trynext(conn);
return;
}
conn->lastactivity = time(NULL);
/* If we don't even have the first 12 bytes then do nothing */
conn->proxy_header_received += read;
if (conn->proxy_header_received < 12)
return;
/* We only support a specific version of the proxy protocol */
if (aimutil_get16(&conn->proxy_header[2]) != PEER_PROXY_PACKET_VERSION)
{
purple_debug_warning("oscar", "Expected peer proxy protocol "
"version %u but received version %u. Closing "
"connection.\n", PEER_PROXY_PACKET_VERSION,
aimutil_get16(&conn->proxy_header[2]));
peer_connection_trynext(conn);
return;
}
/* Initialize a new temporary ProxyFrame for incoming data */
frame = g_new0(ProxyFrame, 1);
frame->payload.len = aimutil_get16(&conn->proxy_header[0]) - 10;
frame->version = aimutil_get16(&conn->proxy_header[2]);
frame->type = aimutil_get16(&conn->proxy_header[4]);
frame->unknown = aimutil_get16(&conn->proxy_header[6]);
frame->flags = aimutil_get16(&conn->proxy_header[10]);
if (frame->payload.len > 0)
frame->payload.data = g_new(guint8, frame->payload.len);
conn->frame = frame;
}
/* If this frame has a payload then attempt to read it */
if (frame->payload.len - frame->payload.offset > 0)
{
/* Read data into the temporary buffer until it is complete */
read = recv(conn->fd,
&frame->payload.data[frame->payload.offset],
frame->payload.len - frame->payload.offset,
0);
/* Check if the proxy server closed the connection */
if (read == 0)
{
purple_debug_info("oscar", "Peer proxy server closed connection\n");
g_free(frame->payload.data);
g_free(frame);
conn->frame = NULL;
peer_connection_trynext(conn);
return;
}
/* If there was an error then close the connection */
if (read < 0)
{
if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
/* No worries */
return;
purple_debug_info("oscar", "Lost connection with peer proxy server\n");
g_free(frame->payload.data);
g_free(frame);
conn->frame = NULL;
peer_connection_trynext(conn);
return;
}
frame->payload.offset += read;
}
conn->lastactivity = time(NULL);
if (frame->payload.offset < frame->payload.len)
/* Waiting for more data to arrive */
return;
/* We have a complete proxy frame! Handle it and continue reading */
conn->frame = NULL;
byte_stream_rewind(&frame->payload);
peer_proxy_recv_frame(conn, frame);
g_free(frame->payload.data);
g_free(frame);
conn->proxy_header_received = 0;
}
/**
* Read in all available data on the socket for a given connection.
* All complete FLAPs handled immedate after they're received.
* Incomplete FLAP data is stored locally and appended to the next
* time this callback is triggered.
*
* This is called by flap_connection_recv_cb and
* flap_connection_recv_cb_ssl for unencrypted/encrypted connections.
*/
static void
flap_connection_recv(FlapConnection *conn)
{
gpointer buf;
gsize buflen;
gssize read;
/* Read data until we run out of data and break out of the loop */
while (TRUE)
{
/* Start reading a new FLAP */
if (conn->buffer_incoming.data.data == NULL)
{
buf = conn->header + conn->header_received;
buflen = 6 - conn->header_received;
/* Read the first 6 bytes (the FLAP header) */
if (conn->gsc)
read = purple_ssl_read(conn->gsc, buf, buflen);
else
read = recv(conn->fd, buf, buflen, 0);
/* Check if the FLAP server closed the connection */
if (read == 0)
{
flap_connection_schedule_destroy(conn,
OSCAR_DISCONNECT_REMOTE_CLOSED, NULL);
break;
}
/* If there was an error then close the connection */
if (read < 0)
{
if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
/* No worries */
break;
/* Error! */
flap_connection_schedule_destroy(conn,
OSCAR_DISCONNECT_LOST_CONNECTION, g_strerror(errno));
break;
}
conn->od->gc->last_received = time(NULL);
/* If we don't even have a complete FLAP header then do nothing */
conn->header_received += read;
if (conn->header_received < 6)
break;
/* All FLAP frames must start with the byte 0x2a */
if (aimutil_get8(&conn->header[0]) != 0x2a)
{
flap_connection_schedule_destroy(conn,
OSCAR_DISCONNECT_INVALID_DATA, NULL);
break;
}
/* Initialize a new temporary FlapFrame for incoming data */
conn->buffer_incoming.channel = aimutil_get8(&conn->header[1]);
conn->buffer_incoming.seqnum = aimutil_get16(&conn->header[2]);
conn->buffer_incoming.data.len = aimutil_get16(&conn->header[4]);
conn->buffer_incoming.data.data = g_new(guint8, conn->buffer_incoming.data.len);
conn->buffer_incoming.data.offset = 0;
}
buflen = conn->buffer_incoming.data.len - conn->buffer_incoming.data.offset;
if (buflen)
{
buf = &conn->buffer_incoming.data.data[conn->buffer_incoming.data.offset];
/* Read data into the temporary FlapFrame until it is complete */
if (conn->gsc)
read = purple_ssl_read(conn->gsc, buf, buflen);
else
read = recv(conn->fd, buf, buflen, 0);
/* Check if the FLAP server closed the connection */
if (read == 0)
{
flap_connection_schedule_destroy(conn,
OSCAR_DISCONNECT_REMOTE_CLOSED, NULL);
break;
}
if (read < 0)
{
if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
/* No worries */
break;
/* Error! */
flap_connection_schedule_destroy(conn,
OSCAR_DISCONNECT_LOST_CONNECTION, g_strerror(errno));
break;
}
conn->buffer_incoming.data.offset += read;
if (conn->buffer_incoming.data.offset < conn->buffer_incoming.data.len)
/* Waiting for more data to arrive */
break;
}
/* We have a complete FLAP! Handle it and continue reading */
byte_stream_rewind(&conn->buffer_incoming.data);
parse_flap(conn->od, conn, &conn->buffer_incoming);
conn->lastactivity = time(NULL);
g_free(conn->buffer_incoming.data.data);
conn->buffer_incoming.data.data = NULL;
conn->header_received = 0;
}
}
