583 lines
19 KiB
C
583 lines
19 KiB
C
/* frames.c - handle incoming frames, prefill outgoing frames, parse TLVs etc. */
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/* Copyright (C) 1999 Heikki Vatiainen hessu@cs.tut.fi */
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/* Functions for handling LANE control frames used when joining an
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* ELAN are in lec.c
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*/
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include <atm.h>
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#include <linux/atmlec.h>
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#include <atmd.h>
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#include "conn.h"
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#include "lec.h"
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#include "frames.h"
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#include "display.h"
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#include "kernel.h"
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#define COMPONENT "frames.c"
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static uint32_t transaction_id = 0;
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static void extract_tlv_value(uint16_t opcode, uint32_t type, unsigned char *tlvp, int len);
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static void handle_x5(uint16_t opcode);
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/* Initializes LANE Control frame of type 'type'
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*/
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void prefill_frame(void *buff, uint16_t type)
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{
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struct frame_hdr *header;
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memset(buff, 0, sizeof(struct ctrl_frame));
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header = (struct frame_hdr *)buff;
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header->marker = htons(0xff00);
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header->protocol = 0x01;
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header->version = 0x01;
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header->opcode = htons(type);
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header->status = htons(0x0000);
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header->tran_id = htonl(transaction_id);
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header->lec_id = htons(lec_params.c14_lec_id);
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header->flags = htons(0x0000);
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transaction_id++;
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return;
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}
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/* Validates incoming Control frames except READY_IND and
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* READY_QUERY which do not start with the common header.
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* Also calls display_frame() to print out conforming frames.
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* Returns < 0 for error
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*/
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int validate_frame(unsigned char *buff, int size)
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{
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struct ready_frame *hdr; /* Ready is the shortest possible */
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if (size < sizeof(struct ready_frame)) {
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diag(COMPONENT, DIAG_DEBUG, "short frame, size %d\n", size);
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return -1;
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}
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hdr = (struct ready_frame *)buff;
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if (hdr->marker != htons(0xff00) ||
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hdr->protocol != 0x01 ||
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hdr->version != 0x01)
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return -1;
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/* READY_* frames are shorter than others */
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if (hdr->opcode == htons(READY_QUERY) ||
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hdr->opcode == htons(READY_IND)) {
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diag(COMPONENT, DIAG_DEBUG, "Received a %s\n", opcode2text(hdr->opcode));
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return 0;
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}
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if (size < sizeof(struct ctrl_frame)) {
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diag(COMPONENT, DIAG_DEBUG, "short frame, size %d\n", size);
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return -1;
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}
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display_frame(buff);
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return 0;
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}
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/* Handle incoming LE_FLUSH_REQUEST frames.
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*/
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static void handle_flush_req(struct ctrl_frame *f)
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{
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if (memcmp(lec_params.c1n_my_atm_addr, f->target_atm_addr, ATM_ESA_LEN) != 0)
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return;
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f->header.opcode = htons(LE_FLUSH_RSP);
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if (send_frame(lec_params.ctrl_direct, f, sizeof(struct ctrl_frame)) < 0)
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diag(COMPONENT, DIAG_DEBUG, "could not send LE_FLUSH_RESPONSE\n");
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return;
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}
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/* Handle incoming LE_FLUSH_RESPONSE frames.
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*/
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static void handle_flush_rsp(struct ctrl_frame *f)
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{
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struct atmlec_msg msg;
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if (f->header.lec_id != htons(lec_params.c14_lec_id)) {
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diag(COMPONENT, DIAG_DEBUG, "Wrong lec_id, ignoring\n");
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return;
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}
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memset(&msg, 0, sizeof(struct atmlec_msg));
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msg.type = l_flush_complete;
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msg.content.normal.flag = ntohl(f->header.tran_id);
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msg_to_kernel(&msg, sizeof(struct atmlec_msg));
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return;
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}
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/* Handle incoming READY_QUERY frames.
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*/
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static void handle_ready_query(Conn_t *conn, struct ready_frame *f)
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{
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f->opcode = htons(READY_IND);
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send_frame(conn, f, sizeof(struct ready_frame));
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return;
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}
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/* Helper for handle_le_arp_req.
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* If the target_lan_dst was not our MAC address, try to
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* see if the bridging table in the kernel knows about it.
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* Returns < 0 for serious error
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*/
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static int check_bridge(struct ctrl_frame *frame, int size)
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{
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struct atmlec_msg msg;
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if (lec_params.c4_proxy_flag == 0)
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return 0;
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memset(&msg, 0, sizeof(struct atmlec_msg));
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msg.type = l_should_bridge;
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memcpy(msg.content.proxy.mac_addr, frame->target_lan_dst.mac, ETH_ALEN);
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memcpy(msg.content.proxy.atm_addr, frame->src_atm_addr, ATM_ESA_LEN);
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msg.content.proxy.tran_id = frame->header.tran_id;
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msg.content.proxy.lec_id = frame->header.lec_id;
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return msg_to_kernel(&msg, sizeof(struct atmlec_msg));
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}
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/* Handles incoming LE_ARP_REQ and targetless LE_ARP_REQ.
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* See LANEv2, 7.1.5 and 7.1.30
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* Returns < 0 for serious error
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*/
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static int handle_le_arp_req(struct ctrl_frame *frame, int size)
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{
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int sizeoftlvs, sizeofrsp, retval;
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struct ctrl_frame *rsp;
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struct atmlec_msg *msg;
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if (frame->header.lec_id == htons(lec_params.c14_lec_id)) {
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diag(COMPONENT, DIAG_DEBUG, "Ignoring own LE_ARP_REQUEST\n");
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return 0;
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}
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retval = 0;
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if (frame->target_lan_dst.tag == htons(LAN_DST_MAC_ADDR)) {
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if (memcmp(frame->target_lan_dst.mac, lec_params.c6_mac_addr, ETH_ALEN) != 0)
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return (check_bridge(frame, size)); /* target was not us */
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sizeofrsp = sizeof(struct ctrl_frame) + lec_params.sizeoftlvs;
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rsp = (struct ctrl_frame *)malloc(sizeofrsp);
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if (rsp == NULL) return 0;
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memcpy(rsp, frame, sizeof(struct ctrl_frame));
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rsp->header.opcode = htons(LE_ARP_RSP);
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memcpy(rsp->target_atm_addr, lec_params.c1n_my_atm_addr, ATM_ESA_LEN);
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rsp->num_tlvs = lec_params.num_tlvs;
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if (lec_params.num_tlvs > 0)
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memcpy(rsp + 1, lec_params.tlvs, lec_params.sizeoftlvs);
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retval = send_frame(lec_params.ctrl_direct, rsp, sizeofrsp);
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free(rsp);
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} else if (frame->target_lan_dst.tag == htons(LAN_DST_NOT_PRESENT) &&
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lec_params.c29_v2_capable) {
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sizeoftlvs = size - sizeof(struct ctrl_frame);
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msg = (struct atmlec_msg *)malloc(sizeof(struct atmlec_msg) + sizeoftlvs);
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if (msg == NULL) return -1;
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memset(msg, 0, sizeof(struct atmlec_msg));
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msg->type = l_arp_update;
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memcpy(msg->content.normal.mac_addr, frame->src_lan_dst.mac, ETH_ALEN);
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memcpy(msg->content.normal.atm_addr, frame->src_atm_addr, ATM_ESA_LEN);
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msg->content.normal.flag = (frame->header.flags & REMOTE_ADDRESS) ? 1 : 0;
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msg->content.normal.targetless_le_arp = 1;
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msg->sizeoftlvs = sizeoftlvs;
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if (sizeoftlvs > 0) memcpy(msg + 1, frame + 1, sizeoftlvs);
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retval = msg_to_kernel(msg, sizeof(struct atmlec_msg) + sizeoftlvs);
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free(msg);
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}
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return retval;
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}
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/* Handles incoming LE_NARP_REQUESTS frames.
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* Mandatory only in LANEv2. If we are LANEv1, we'll just ignore these.
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* See LANEv2, 7.1.31-35 LE_NARP_REQUEST/RESPONSE.
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* For no-source, i.e. no source ATM address, we remove the LE_ARP cache entry.
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* If the source is non-zero, we first remove the entry
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* and then add the new entry in the LE_ARP cache.
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* Returns < 0 for serious error.
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*/
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static int handle_narp_req(struct ctrl_frame *frame, int size)
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{
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int sizeoftlvs, no_source = 0, retval;
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struct atmlec_msg *msg;
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unsigned char empty[ATM_ESA_LEN];
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if (frame->header.lec_id == htons(lec_params.c14_lec_id) ||
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lec_params.c29_v2_capable == 0) {
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diag(COMPONENT, DIAG_DEBUG, "Ignoring LE_NARP_REQUEST\n");
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return 0;
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}
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memset(empty, 0, ATM_ESA_LEN);
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if (memcmp(empty, frame->src_atm_addr, ATM_ESA_LEN) == 0)
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no_source = 1;
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sizeoftlvs = size - sizeof(struct ctrl_frame);
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msg = (struct atmlec_msg *)malloc(sizeof(struct atmlec_msg) + sizeoftlvs);
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if (msg == NULL) return -1;
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memset(msg, 0, sizeof(struct atmlec_msg));
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msg->type = l_narp_req;
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memcpy(msg->content.normal.mac_addr, frame->src_lan_dst.mac, ETH_ALEN);
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memcpy(msg->content.normal.atm_addr, frame->src_atm_addr, ATM_ESA_LEN);
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msg->content.normal.flag = (frame->header.flags & REMOTE_ADDRESS) ? 1 : 0;
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msg->content.normal.no_source_le_narp = no_source;
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msg->sizeoftlvs = sizeoftlvs;
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if (sizeoftlvs > 0) memcpy(msg + 1, frame + 1, sizeoftlvs);
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retval = msg_to_kernel(msg, sizeof(struct atmlec_msg) + sizeoftlvs);
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free(msg);
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return retval;
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}
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/* Handles incoming LE_ARP_RESPONSE frames.
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* Returns < 0 for serious error
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*/
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static int handle_arp_rsp(struct ctrl_frame *frame, int size)
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{
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int sizeoftlvs, msglen, retval;
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char buff[MAX_CTRL_FRAME];
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struct atmlec_msg *msg;
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if (frame->header.lec_id != htons(lec_params.c14_lec_id)) {
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diag(COMPONENT, DIAG_DEBUG, "Wrong lec_id, ignoring\n");
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return 0;
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}
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sizeoftlvs = size - sizeof(struct ctrl_frame);
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msglen = sizeof(struct atmlec_msg) + sizeoftlvs;
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msg = (struct atmlec_msg *)buff;
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memset(msg, 0, msglen);
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msg->type = l_arp_update;
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memcpy(msg->content.normal.mac_addr, frame->target_lan_dst.mac, ETH_ALEN);
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memcpy(msg->content.normal.atm_addr, frame->target_atm_addr, ATM_ESA_LEN);
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msg->content.normal.flag = (frame->header.flags & REMOTE_ADDRESS) ? 1 : 0;
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msg->sizeoftlvs = sizeoftlvs;
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if (sizeoftlvs > 0) memcpy(msg + 1, frame + 1, sizeoftlvs);
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retval = msg_to_kernel(msg, msglen);
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return retval;
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}
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/* Handles incoming LE_TOPOLOGY_REQUEST frames.
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* Returns < 0 for serious error
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*/
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static int handle_topo_req(struct ctrl_frame *frame)
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{
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struct atmlec_msg msg;
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memset(&msg, 0, sizeof(struct atmlec_msg));
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msg.type = l_topology_change;
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if (frame->header.flags & htons(TOPO_CHANGE))
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msg.content.normal.flag = 1;
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return(msg_to_kernel(&msg, sizeof(struct atmlec_msg)));
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}
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/* Processes and validates incoming frames. Calls frame
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* dependant handler functions.
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* Returns < 0 for serious error
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*/
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int handle_frame(Conn_t *conn, char *buff, int size)
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{
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struct ctrl_frame *frame;
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if (validate_frame(buff, size) < 0)
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return 0;
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frame = (struct ctrl_frame *)buff;
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switch (ntohs(frame->header.opcode)) {
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case LE_FLUSH_REQ:
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handle_flush_req(frame);
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break;
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case LE_FLUSH_RSP:
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handle_flush_rsp(frame);
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break;
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case READY_QUERY:
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handle_ready_query(conn, (struct ready_frame *)frame);
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break;
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case READY_IND:
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/* We can ignore these */
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break;
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case LE_ARP_REQ:
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if (handle_le_arp_req(frame, size) < 0)
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return -1;
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break;
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case LE_ARP_RSP:
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if (handle_arp_rsp(frame, size) < 0)
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return -1;
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break;
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case LE_TOPO_REQ:
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if (handle_topo_req(frame) < 0)
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return -1;
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break;
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case LE_REG_RSP:
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/* FIXME: Should we do something? */
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break;
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case LE_NARP_REQ:
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if (handle_narp_req(frame, size) < 0)
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return -1;
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break;
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default:
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diag(COMPONENT, DIAG_ERROR,
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"Unknown frame, opcode 0x%x %s\n", ntohs(frame->header.opcode),
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opcode2text(frame->header.opcode));
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break;
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}
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return 0;
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}
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/* Sends a READY_INDICATION when a non-blocking connect completes.
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*/
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void send_ready_ind(Conn_t *conn)
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{
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struct ready_frame frame;
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int retval;
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frame.marker = htons(0xff00);
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frame.protocol = 0x01;
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frame.version = 0x01;
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frame.opcode = htons(READY_IND);
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retval = send_frame(conn, &frame, sizeof(struct ready_frame));
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if (retval < 0)
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diag(COMPONENT, DIAG_DEBUG, "Could not send READY_IND, fd %d\n", conn->fd);
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return;
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}
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/* Sends a LE_FLUSH_REQUEST
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* Returns the transaction used with this flush REQ/RSP pair.
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*/
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uint32_t send_flush_req(Conn_t *conn)
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{
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struct ctrl_frame frame;
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prefill_frame(&frame, LE_FLUSH_REQ);
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memcpy(frame.src_atm_addr, lec_params.c1n_my_atm_addr, ATM_ESA_LEN);
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memcpy(frame.target_atm_addr, conn->atm_address, ATM_ESA_LEN);
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send_frame(lec_params.mcast_send, &frame, sizeof(struct ctrl_frame));
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return ntohl(frame.header.tran_id);
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}
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/* Registers our MAC address and associated TLVs with LES.
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* See LANEv2, 6. Registaration Protocol
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*/
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void send_register_req(void)
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{
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char buff[MAX_CTRL_FRAME];
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struct ctrl_frame *frame;
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frame = (struct ctrl_frame *)buff;
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prefill_frame(frame, LE_REG_REQ);
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frame->src_lan_dst.tag = htons(LAN_DST_MAC_ADDR);
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memcpy(frame->src_lan_dst.mac, lec_params.c6_mac_addr, ETH_ALEN);
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memcpy(frame->src_atm_addr, lec_params.c1n_my_atm_addr, ATM_ESA_LEN);
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frame->num_tlvs = lec_params.num_tlvs;
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if (lec_params.sizeoftlvs > 0)
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memcpy((frame + 1), lec_params.tlvs, lec_params.sizeoftlvs);
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send_frame(lec_params.ctrl_direct, frame, sizeof(struct ctrl_frame) + lec_params.sizeoftlvs);
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return;
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}
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/* Goes through the TLVs trailing a frame while passing them
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* one by one to the TLV handler.
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*/
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void parse_tlvs(uint16_t opcode, unsigned char *tlvp, int numtlvs, int sizeoftlvs)
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{
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uint32_t type;
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uint8_t len;
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unsigned char *end_of_tlvs;
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end_of_tlvs = tlvp + sizeoftlvs;
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while (numtlvs-- > 0 && end_of_tlvs - tlvp >= 5) {
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type = *(uint32_t *)tlvp;
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type = ntohl(type);
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len = tlvp[4];
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tlvp += 5;
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diag(COMPONENT, DIAG_DEBUG, "parse_tlvs: type %s len %d\n",
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tlv2text(type), len);
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if (tlvp + len > end_of_tlvs)
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return; /* value too long */
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extract_tlv_value(opcode, type, tlvp, len);
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tlvp += len;
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}
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return;
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}
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/* Does something depending on the frame type this TLV arrived with,
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* TLV type, and contents of TLV.
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*/
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static void extract_tlv_value(uint16_t opcode, uint32_t type, unsigned char *tlvp, int len)
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{
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uint16_t value16;
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uint32_t value32;
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/* LE_JOIN_RESPONSE does not support all the TLVs */
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if (opcode == htons(LE_JOIN_RSP) && type != htonl(ELAN_ID))
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return;
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switch(len) {
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case 0:
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switch (type) {
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case X5_ADJUSTMENT:
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handle_x5(opcode);
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break;
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default:
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goto whine;
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break;
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}
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break;
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case 2:
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value16 = *(uint16_t *)tlvp;
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value16 = ntohs(value16);
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diag(COMPONENT, DIAG_DEBUG, "value of TLV %d\n", value16);
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switch (type) {
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case MAX_CUM_CTRL_TIMEOUT:
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lec_params.c7_ctrl_timeout = value16;
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break;
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case MAX_UNKNOWN_FRAME_CNT:
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lec_params.c10_max_unknown_frames = value16;
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break;
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case MAX_UNKNOWN_FRAME_TIME:
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lec_params.c11_max_unknown_frame_time = value16;
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break;
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case MAX_RETRY_COUNT:
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lec_params.c13_max_retry_count = value16;
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break;
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case FORWARD_DELAY_TIME:
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lec_params.c18_forward_delay_time = value16;
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break;
|
|
case EXPECTED_LE_ARP_TIME:
|
|
lec_params.c20_le_arp_response_time = value16;
|
|
break;
|
|
case FLUSH_TIMEOUT:
|
|
lec_params.c21_flush_timeout = value16;
|
|
break;
|
|
case PATH_SWITCHING_DELAY:
|
|
lec_params.c22_path_switching_delay = value16;
|
|
break;
|
|
case LOCAL_SEGMENT_ID:
|
|
case DEF_MCAST_SND_VCC_TYPE:
|
|
case CONN_COMPLETION_TIMER:
|
|
case SERVICE_CATEGORY:
|
|
/* do nothing */
|
|
break;
|
|
default:
|
|
goto whine;
|
|
break;
|
|
}
|
|
break;
|
|
case 4:
|
|
value32 = *(uint32_t *)tlvp;
|
|
value32 = ntohl(value32);
|
|
diag(COMPONENT, DIAG_DEBUG, "value of TLV %d\n", value32);
|
|
switch (type) {
|
|
case VCC_TIMEOUT_PERIOD:
|
|
lec_params.c12_vcc_timeout = value32;
|
|
break;
|
|
case AGING_TIME:
|
|
lec_params.c17_aging_time = value32;
|
|
break;
|
|
case ELAN_ID:
|
|
lec_params.c31_elan_id = value32;
|
|
break;
|
|
case DEF_MCAST_SND_VCC_AVG:
|
|
case DEF_MCAST_SEND_PEAK_RT:
|
|
/* do nothing */
|
|
break;
|
|
default:
|
|
goto whine;
|
|
break;
|
|
}
|
|
break;
|
|
case 20:
|
|
switch(type) {
|
|
case PREFERRED_LES:
|
|
memcpy(lec_params.c35_preferred_les, tlvp, ATM_ESA_LEN);
|
|
lec_params.c35_contains_address = 1;
|
|
break;
|
|
case LLC_MUXED_ATM_ADDR:
|
|
/* do nothing */
|
|
break;
|
|
default:
|
|
goto whine;
|
|
break;
|
|
}
|
|
break;
|
|
default:
|
|
/* handle variable length TLVs */
|
|
switch(type) {
|
|
case CONFIG_FRAG_INFO:
|
|
diag(COMPONENT, DIAG_INFO, "Got Config-Frag-Info TLV\n");
|
|
break;
|
|
case LAYER3_ADDRESS:
|
|
/* do nothing */
|
|
break;
|
|
default:
|
|
goto whine;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
|
|
return;
|
|
|
|
whine:
|
|
diag(COMPONENT, DIAG_DEBUG, "Unknown TLV, type 0x%x, len %d\n", type, len);
|
|
|
|
return;
|
|
}
|
|
|
|
/* Figures out what to do when we get a X5-Adjustment TLV
|
|
*/
|
|
static void handle_x5(uint16_t opcode)
|
|
{
|
|
if (!lec_params.c29_v2_capable)
|
|
return;
|
|
if (opcode != ntohs(LE_CONFIG_RSP)) {
|
|
diag(COMPONENT, DIAG_WARN, "X5-Adjustment TLV received but not with LE_CONFIG_RSP\n");
|
|
return;
|
|
}
|
|
|
|
switch(lec_params.c3_max_frame_size) {
|
|
case 1:
|
|
lec_params.c3_max_frame_size = 5; /* 1580 */
|
|
return;
|
|
break;
|
|
case 2:
|
|
lec_params.c3_max_frame_size = 5; /* 1580 */
|
|
return;
|
|
break;
|
|
default:
|
|
/* rest of the values are not affected by X5 */
|
|
break;
|
|
}
|
|
|
|
return;
|
|
}
|