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| author | Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> | 2014-10-28 16:09:17 +0530 |
|---|---|---|
| committer | Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> | 2014-10-29 17:02:08 +0530 |
| commit | 1f33e4f29e8cf4ba14e75d8fa37fd9ba0ea09c53 (patch) | |
| tree | f84498b942fa111803bf223dd1389b12132dcb6b /clients | |
| parent | b931c7bc10a3c29a8ca0e693d4dfb94f17311451 (diff) | |
| download | SLOF-1f33e4f29e8cf4ba14e75d8fa37fd9ba0ea09c53.zip SLOF-1f33e4f29e8cf4ba14e75d8fa37fd9ba0ea09c53.tar.gz SLOF-1f33e4f29e8cf4ba14e75d8fa37fd9ba0ea09c53.tar.bz2 | |
ipv4: Fix send packet across a subnet
The send packet code does understand that the IP is not part of the
current network and needs to use the router. And then tries to get the
MAC address of the router IP from arp cache, that fails. This is
becuase there was no ARP Request send for the router IP.
So in case when there is router involved, send arp request for the
router IP and after the reply, we have the router mac cached to
communicate with.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Diffstat (limited to 'clients')
| -rw-r--r-- | clients/net-snk/app/netlib/ipv4.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/clients/net-snk/app/netlib/ipv4.c b/clients/net-snk/app/netlib/ipv4.c index 1d5dd73..8185de5 100644 --- a/clients/net-snk/app/netlib/ipv4.c +++ b/clients/net-snk/app/netlib/ipv4.c @@ -428,6 +428,7 @@ send_ipv4(int fd, void* buffer, int len) arp_entry_t *arp_entry = 0; struct iphdr *ip; const uint8_t *mac_addr = 0; + uint32_t ip_dst = 0; if(len + sizeof(struct ethhdr) > ETH_MTU_SIZE) return -1; @@ -459,6 +460,7 @@ send_ipv4(int fd, void* buffer, int len) fill_udp_checksum(ip); } + ip_dst = ip->ip_dst; // Check if the MAC address is already cached if(~ip->ip_dst == 0 || ( ((~subnet_mask) & ip->ip_dst) == ~subnet_mask && @@ -475,8 +477,10 @@ send_ipv4(int fd, void* buffer, int len) if((subnet_mask & own_ip) == (subnet_mask & ip->ip_dst)) arp_entry = lookup_mac_addr(ip->ip_dst); // if not then we need to know the router's IP address - else + else { + ip_dst = router_ip; arp_entry = lookup_mac_addr(router_ip); + } if(arp_entry && memcmp(arp_entry->mac_addr, null_mac_addr, 6) != 0) mac_addr = arp_entry->mac_addr; } @@ -484,7 +488,7 @@ send_ipv4(int fd, void* buffer, int len) // If we could not resolv the MAC address by our own... if(!mac_addr) { // send the ARP request - arp_send_request(fd, ip->ip_dst); + arp_send_request(fd, ip_dst); // drop the current packet if there is already a ARP request pending if(arp_entry) @@ -500,9 +504,9 @@ send_ipv4(int fd, void* buffer, int len) // store the packet to be send if the ARP reply is received arp_entry->pkt_pending = 1; - arp_entry->ipv4_addr = ip->ip_dst; + arp_entry->ipv4_addr = ip_dst; memset(arp_entry->mac_addr, 0, 6); - pending_pkt.ipv4_addr = ip->ip_dst; + pending_pkt.ipv4_addr = ip_dst; memset(pending_pkt.mac_addr, 0, 6); fill_ethhdr (pending_pkt.eth_frame, htons(ETHERTYPE_IP), get_mac_address(), null_mac_addr); |