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Several source comment changes.

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This commit is contained in:
likewise 2003-10-02 21:43:18 +00:00
parent 73a095572e
commit 5df9545dcc
1 changed files with 14 additions and 10 deletions
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24
src/netif/etharp.c
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@ -4,8 +4,10 @@
* *
* Functionally, ARP is divided into two parts. The first maps an IP address * Functionally, ARP is divided into two parts. The first maps an IP address
* to a physical address when sending a packet, and the second part answers * to a physical address when sending a packet, and the second part answers
* requests from other machines. * requests from other machines for our physical address.
* *
* This implementation complies with RFC 826 (Ethernet ARP) and supports
* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6.
*/ */
/* /*
@ -497,9 +499,9 @@ etharp_arp_input(struct netif *netif, struct eth_addr *ethaddr, struct pbuf *p)
* returned, ready to be sent. * returned, ready to be sent.
* *
* If ARP does not have the Ethernet address in cache the packet is * If ARP does not have the Ethernet address in cache the packet is
* queued and a ARP request is sent (on a best-effort basis). This * queued (if enabled and space available) and a ARP request is sent.
* ARP request is returned as a pbuf, which should be sent by the * This ARP request is returned as a pbuf, which should be sent by
* caller. * the caller.
* *
* If ARP failed to allocate resources, NULL is returned. * If ARP failed to allocate resources, NULL is returned.
* *
@ -509,7 +511,8 @@ etharp_arp_input(struct netif *netif, struct eth_addr *ethaddr, struct pbuf *p)
* @param ipaddr The IP address of the packet destination. * @param ipaddr The IP address of the packet destination.
* @param pbuf The pbuf(s) containing the IP packet to be sent. * @param pbuf The pbuf(s) containing the IP packet to be sent.
* *
* @return If non-NULL, a packet ready to be sent. * @return If non-NULL, a packet ready to be sent by caller.
*
*/ */
struct pbuf * struct pbuf *
etharp_output(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q) etharp_output(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q)
@ -535,9 +538,9 @@ etharp_output(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q)
/* assume unresolved Ethernet address */ /* assume unresolved Ethernet address */
dest = NULL; dest = NULL;
/* Construct Ethernet header. Start with looking up deciding which /* Construct Ethernet header. Start with looking up deciding which
MAC address to use as a destination address. Broadcasts and MAC address to use as a destination address. Broadcasts and
multicasts are special, all other addresses are looked up in the multicasts are special, all other addresses are looked up in the
ARP table. */ ARP table. */
/* destination IP address is an IP broadcast address? */ /* destination IP address is an IP broadcast address? */
if (ip_addr_isany(ipaddr) || if (ip_addr_isany(ipaddr) ||
@ -549,7 +552,7 @@ etharp_output(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q)
else if (ip_addr_ismulticast(ipaddr)) { else if (ip_addr_ismulticast(ipaddr)) {
/* Hash IP multicast address to MAC address. */ /* Hash IP multicast address to MAC address. */
mcastaddr.addr[0] = 0x01; mcastaddr.addr[0] = 0x01;
mcastaddr.addr[1] = 0x0; mcastaddr.addr[1] = 0x00;
mcastaddr.addr[2] = 0x5e; mcastaddr.addr[2] = 0x5e;
mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f; mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
mcastaddr.addr[4] = ip4_addr3(ipaddr); mcastaddr.addr[4] = ip4_addr3(ipaddr);
@ -577,7 +580,7 @@ etharp_output(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q)
} }
/* Ethernet address for IP destination address is in ARP cache? */ /* Ethernet address for IP destination address is in ARP cache? */
for(i = 0; i < ARP_TABLE_SIZE; ++i) { for (i = 0; i < ARP_TABLE_SIZE; ++i) {
/* match found? */ /* match found? */
if (arp_table[i].state == ETHARP_STATE_STABLE && if (arp_table[i].state == ETHARP_STATE_STABLE &&
ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) { ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
@ -588,6 +591,7 @@ etharp_output(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q)
/* could not find the destination Ethernet address in ARP cache? */ /* could not find the destination Ethernet address in ARP cache? */
if (dest == NULL) { if (dest == NULL) {
/* ARP query for the IP address, submit this IP packet for queueing */ /* ARP query for the IP address, submit this IP packet for queueing */
/* TODO: How do we handle netif->ipaddr == ipaddr? */
etharp_query(netif, ipaddr, q); etharp_query(netif, ipaddr, q);
/* return nothing */ /* return nothing */
return NULL; return NULL;