AmendHub

--- telnet.c Tue Dec 28 22:01:27 2021 +++ telnet.c Sat Jan 1 21:47:57 2022 @@ -88,11 +88,11 @@ enum { struct telnet_node { short id; short state; - TCPiopb pb, listen_pb; + TCPiopb rcv_pb, send_pb, listen_pb; StreamPtr stream; wdsEntry tcp_wds[2]; unsigned short obuflen; - unsigned char obuf[512]; /* this must be session.obuf*2 */ + unsigned char obuf[512]; unsigned char ibuf[64]; unsigned short ibuflen; unsigned short sending_iac; @@ -114,11 +114,12 @@ TCPStatusPB telnet_status_pb; void telnet_atexit(void); void telnet_setup(struct session *session); +short telnet_process_input(struct session *session); void telnet_output_iac(struct session *session, char *iacs, size_t len); struct node_funcs telnet_node_funcs = { telnet_setup, - telnet_input, + telnet_process_input, /* we'll receive input outside of session */ telnet_output, telnet_close }; @@ -182,7 +183,7 @@ telnet_idle(void) node = xmalloczero(sizeof(struct telnet_node)); node->id = n; - error = _TCPCreate(&node->pb, &node->stream, + error = _TCPCreate(&node->send_pb, &node->stream, (Ptr)&node->tcp_buf, sizeof(node->tcp_buf), nil, nil, nil, false); if (error) @@ -202,8 +203,8 @@ telnet_idle(void) switch (node->state) { case TELNET_PB_STATE_LISTENING: - error = _TCPStatus(&node->pb, node->stream, &telnet_status_pb, - nil, nil, false); + error = _TCPStatus(&node->send_pb, node->stream, + &telnet_status_pb, nil, nil, false); if (error == connectionDoesntExist) continue; if (error != noErr) @@ -262,14 +263,14 @@ telnet_input(struct session *session) if (session->ending) return 0; - if (session->ibuflen >= sizeof(session->ibuf)) + if (node->ibuflen >= sizeof(node->ibuf)) return 0; - if (node->pb.ioResult > 0) + if (node->rcv_pb.ioResult > 0) /* previous _TCPSend/_TCPRecv has not completed yet */ return 0; - error = _TCPStatus(&node->pb, node->stream, &telnet_status_pb, nil, + error = _TCPStatus(&node->rcv_pb, node->stream, &telnet_status_pb, nil, nil, false); if (error || telnet_status_pb.connectionState != ConnectionStateEstablished) { @@ -281,20 +282,42 @@ telnet_input(struct session *session) return 0; rlen = telnet_status_pb.amtUnreadData; - if (session->ibuflen + rlen >= sizeof(session->ibuf)) - rlen = sizeof(session->ibuf) - session->ibuflen; + if (node->ibuflen + rlen >= sizeof(node->ibuf)) + rlen = sizeof(node->ibuf) - node->ibuflen; - error = _TCPRcv(&node->pb, node->stream, (Ptr)(node->ibuf), &rlen, - nil, nil, false); + error = _TCPRcv(&node->rcv_pb, node->stream, + (Ptr)(node->ibuf + node->ibuflen), &rlen, nil, nil, false); if (error) { warn("TCPRecv[%d] failed: %d", node->id, error); session->ending = 1; return 0; } + + node->ibuflen += rlen; + + return rlen; +} +short +telnet_process_input(struct session *session) +{ + struct telnet_node *node = (struct telnet_node *)session->cookie; + short error, n; + unsigned char c; + char iac_out[8] = { IAC, 0 }; + + if (node->ibuflen == 0) + return 0; + + if (session->ending) + return 0; + session->last_input_at = Time; - - for (n = 0; n < rlen; n++) { + + for (n = 0; n < node->ibuflen; n++) { + if (session->ibuflen >= sizeof(session->ibuf) - 5) + break; + c = node->ibuf[n]; switch (node->iac_state) { @@ -461,8 +484,16 @@ telnet_input(struct session *session) break; } } - - return rlen; + + if (n) { + node->ibuflen -= n; + if (node->ibuflen == 1) + node->ibuf[0] = node->ibuf[n]; + else if (node->ibuflen != 0) + memmove(node->ibuf, node->ibuf + n, node->ibuflen); + } + + return n; } short @@ -475,17 +506,18 @@ telnet_output(struct session *session) if (session->obuflen == 0 || session->ending) return 0; - if (node->pb.ioResult > 0) + if (node->send_pb.ioResult > 0) /* previous _TCPSend has not completed yet */ return 0; +process_result: if (node->tcp_wds[0].length) { /* previous _TCPSend completed, shift out those bytes */ session->obuflen -= node->obuflen; if (session->obuflen < 0) warn("bogus obuflen %d", session->obuflen); if (session->obuflen > 0) - BlockMove(session->obuf + node->obuflen, session->obuf, + memmove(session->obuf, session->obuf + node->obuflen, session->obuflen); node->tcp_wds[0].length = 0; @@ -496,7 +528,7 @@ telnet_output(struct session *session) /* copy obuf to node buffer, escaping IACs */ for (node->escaped_obuflen = 0, node->obuflen = 0; - node->obuflen < session->obuflen; + node->obuflen < session->obuflen && node->escaped_obuflen < sizeof(node->obuf); node->obuflen++) { c = session->obuf[node->obuflen]; @@ -517,13 +549,17 @@ telnet_output(struct session *session) node->tcp_wds[0].ptr = (Ptr)&node->obuf; node->tcp_wds[0].length = node->escaped_obuflen; - error = _TCPSend(&node->pb, node->stream, node->tcp_wds, nil, nil, + error = _TCPSend(&node->send_pb, node->stream, node->tcp_wds, nil, nil, true); if (error) { warn("TCPSend[%d] failed: %d", node->id, error); session->ending = 1; } + /* if we sent quickly enough, we won't have to cycle again */ + if (node->send_pb.ioResult <= 0) + goto process_result; + return 0; } @@ -532,20 +568,13 @@ telnet_output_iac(struct session *session, char *iacs, { struct telnet_node *node = (struct telnet_node *)session->cookie; - /* flush output buffer */ - while (session->obuflen && !session->ending) - telnet_output(session); - + session_flush(session); if (session->ending) return; node->sending_iac = 1; - session_output(session, iacs, len); - - while (session->obuflen && !session->ending) - telnet_output(session); - + session_flush(session); node->sending_iac = 0; }