int NSCLASS dsr_ack_req_send(struct in_addr neigh_addr, unsigned short id)
{
struct dsr_pkt *dp;
struct dsr_ack_req_opt *ack_req;
int len = DSR_OPT_HDR_LEN + DSR_ACK_REQ_HDR_LEN;
char *buf;
dp = dsr_pkt_alloc(NULL);
dp->dst = neigh_addr;
dp->nxt_hop = neigh_addr;
dp->src = my_addr();
buf = dsr_pkt_alloc_opts(dp, len);
if (!buf)
goto out_err;
dp->nh.iph = dsr_build_ip(dp, dp->src, dp->dst, IP_HDR_LEN,
IP_HDR_LEN + len, IPPROTO_DSR, 1);
if (!dp->nh.iph) {
LOG_DBG("Could not create IP header\n");
goto out_err;
}
dp->dh.opth = dsr_opt_hdr_add(buf, len, DSR_NO_NEXT_HDR_TYPE);
if (!dp->dh.opth) {
LOG_DBG("Could not create DSR opt header\n");
goto out_err;
}
buf += DSR_OPT_HDR_LEN;
len -= DSR_OPT_HDR_LEN;
ack_req = dsr_ack_req_opt_create(buf, len, id);
if (!ack_req) {
LOG_DBG("Could not create ACK REQ opt\n");
goto out_err;
}
LOG_DBG("Sending ACK REQ for %s id=%u\n", print_ip(neigh_addr), id);
XMIT(dp);
return 1;
out_err:
dsr_pkt_free(dp);
return -1;
}
int NSCLASS dsr_opt_remove(struct dsr_pkt *dp)
{
int len, ip_len, prot, ttl;
if (!dp || !dp->dh.raw)
return -1;
prot = dp->dh.opth->nh;
#ifdef NS2
ip_len = 20;
ttl = dp->nh.iph->ttl();
#else
ip_len = (dp->nh.iph->ihl << 2);
ttl = dp->nh.iph->ttl;
#endif
dsr_build_ip(dp, dp->src, dp->dst, ip_len,
ip_len + dp->payload_len, prot, ttl);
len = dsr_pkt_free_opts(dp);
/* Return bytes removed */
return len;
}
int NSCLASS dsr_ack_send(struct in_addr dst, unsigned short id)
{
struct dsr_pkt *dp;
struct dsr_ack_opt *ack_opt;
int len;
char *buf;
/* srt = dsr_rtc_find(my_addr(), dst); */
/* if (!srt) { */
/* LOG_DBG("No source route to %s\n", print_ip(dst.s_addr)); */
/* return -1; */
/* } */
len = DSR_OPT_HDR_LEN + /* DSR_SRT_OPT_LEN(srt) + */ DSR_ACK_HDR_LEN;
dp = dsr_pkt_alloc(NULL);
dp->dst = dst;
/* dp->srt = srt; */
dp->nxt_hop = dst; //dsr_srt_next_hop(dp->srt, 0);
dp->src = my_addr();
buf = dsr_pkt_alloc_opts(dp, len);
if (!buf)
goto out_err;
dp->nh.iph = dsr_build_ip(dp, dp->src, dp->dst, IP_HDR_LEN,
IP_HDR_LEN + len, IPPROTO_DSR, IPDEFTTL);
if (!dp->nh.iph) {
LOG_DBG("Could not create IP header\n");
goto out_err;
}
dp->dh.opth = dsr_opt_hdr_add(buf, len, DSR_NO_NEXT_HDR_TYPE);
if (!dp->dh.opth) {
LOG_DBG("Could not create DSR opt header\n");
goto out_err;
}
buf += DSR_OPT_HDR_LEN;
len -= DSR_OPT_HDR_LEN;
/* dp->srt_opt = dsr_srt_opt_add(buf, len, dp->srt); */
/* if (!dp->srt_opt) { */
/* LOG_DBG("Could not create Source Route option header\n"); */
/* goto out_err; */
/* } */
/* buf += DSR_SRT_OPT_LEN(dp->srt); */
/* len -= DSR_SRT_OPT_LEN(dp->srt); */
ack_opt = dsr_ack_opt_add(buf, len, dp->src, dp->dst, id);
if (!ack_opt) {
LOG_DBG("Could not create DSR ACK opt header\n");
goto out_err;
}
LOG_DBG("Sending ACK to %s id=%u\n", print_ip(dst), id);
dp->flags |= PKT_XMIT_JITTER;
XMIT(dp);
return 1;
out_err:
dsr_pkt_free(dp);
return -1;
}
struct dsr_ack_req_opt *NSCLASS
dsr_ack_req_opt_add(struct dsr_pkt *dp, unsigned short id)
{
char *buf = NULL;
int prot = 0, tot_len = 0, ttl = IPDEFTTL;
if (!dp)
return NULL;
/* If we are forwarding a packet and there is already an ACK REQ option,
* we just overwrite the old one. */
if (dp->ack_req_opt) {
buf = (char *)dp->ack_req_opt;
goto end;
}
#ifdef NS2
if (dp->p) {
hdr_cmn *cmh = HDR_CMN(dp->p);
prot = cmh->ptype();
} else
prot = DSR_NO_NEXT_HDR_TYPE;
ttl = dp->nh.iph->ttl();
#else
if (dp->nh.raw) {
tot_len = ntohs(dp->nh.iph->tot_len);
prot = dp->nh.iph->protocol;
ttl = dp->nh.iph->ttl;
}
#endif
if (!dsr_pkt_opts_len(dp)) {
buf =
dsr_pkt_alloc_opts(dp,
DSR_OPT_HDR_LEN + DSR_ACK_REQ_HDR_LEN);
LOG_DBG("Allocating options for ACK REQ\n");
if (!buf)
return NULL;
dsr_build_ip(dp, dp->src, dp->dst, IP_HDR_LEN,
tot_len + DSR_OPT_HDR_LEN + DSR_ACK_REQ_HDR_LEN,
IPPROTO_DSR, ttl);
dp->dh.opth =
dsr_opt_hdr_add(buf, DSR_OPT_HDR_LEN + DSR_ACK_REQ_HDR_LEN,
prot);
if (!dp->dh.opth) {
return NULL;
}
buf += DSR_OPT_HDR_LEN;
} else {
buf = dsr_pkt_alloc_opts_expand(dp, DSR_ACK_REQ_HDR_LEN);
LOG_DBG("Expanding options for ACK REQ p_len=%d\n",
ntohs(dp->dh.opth->p_len));
if (!buf)
return NULL;
dsr_build_ip(dp, dp->src, dp->dst, IP_HDR_LEN,
tot_len + DSR_ACK_REQ_HDR_LEN, IPPROTO_DSR, ttl);
dp->dh.opth =
dsr_opt_hdr_add(dp->dh.raw,
DSR_OPT_HDR_LEN +
ntohs(dp->dh.opth->p_len) +
DSR_ACK_REQ_HDR_LEN, dp->dh.opth->nh);
}
LOG_DBG("Added ACK REQ option id=%u\n", id, ntohs(dp->dh.opth->p_len));
end:
return dsr_ack_req_opt_create(buf, DSR_ACK_REQ_HDR_LEN, id);
}
