GRUB_NET_ARPHRD_ETHERNET = 1
};
-struct arphdr {
+struct arppkt {
grub_uint16_t hrd;
grub_uint16_t pro;
grub_uint8_t hln;
grub_uint8_t pln;
grub_uint16_t op;
+ grub_uint8_t sender_mac[6];
+ grub_uint32_t sender_ip;
+ grub_uint8_t recv_mac[6];
+ grub_uint32_t recv_ip;
} GRUB_PACKED;
static int have_pending;
const grub_net_network_level_address_t *proto_addr)
{
struct grub_net_buff nb;
- struct arphdr *arp_header;
- grub_net_link_level_address_t target_hw_addr;
- grub_uint8_t *aux, arp_data[128];
+ struct arppkt *arp_packet;
+ grub_net_link_level_address_t target_mac_addr;
grub_err_t err;
int i;
- grub_size_t addrlen;
- grub_uint16_t etherpro;
grub_uint8_t *nbd;
+ grub_uint8_t arp_data[128];
- if (proto_addr->type == GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4)
- {
- addrlen = 4;
- etherpro = GRUB_NET_ETHERTYPE_IP;
- }
- else
+ if (proto_addr->type != GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4)
return grub_error (GRUB_ERR_BUG, "unsupported address family");
/* Build a request packet. */
grub_netbuff_clear (&nb);
grub_netbuff_reserve (&nb, 128);
- err = grub_netbuff_push (&nb, sizeof (*arp_header) + 2 * (6 + addrlen));
+ err = grub_netbuff_push (&nb, sizeof (*arp_packet));
if (err)
return err;
- arp_header = (struct arphdr *) nb.data;
- arp_header->hrd = grub_cpu_to_be16 (GRUB_NET_ARPHRD_ETHERNET);
- arp_header->hln = 6;
- arp_header->pro = grub_cpu_to_be16 (etherpro);
- arp_header->pln = addrlen;
- arp_header->op = grub_cpu_to_be16 (ARP_REQUEST);
- aux = (grub_uint8_t *) arp_header + sizeof (*arp_header);
+ arp_packet = (struct arppkt *) nb.data;
+ arp_packet->hrd = grub_cpu_to_be16_compile_time (GRUB_NET_ARPHRD_ETHERNET);
+ arp_packet->hln = 6;
+ arp_packet->pro = grub_cpu_to_be16 (GRUB_NET_ETHERTYPE_IP);
+ arp_packet->pln = 4;
+ arp_packet->op = grub_cpu_to_be16_compile_time (ARP_REQUEST);
/* Sender hardware address. */
- grub_memcpy (aux, &inf->hwaddress.mac, 6);
-
- aux += 6;
- /* Sender protocol address */
- grub_memcpy (aux, &inf->address.ipv4, 4);
- aux += addrlen;
- /* Target hardware address */
- for (i = 0; i < 6; i++)
- aux[i] = 0x00;
- aux += 6;
+ grub_memcpy (arp_packet->sender_mac, &inf->hwaddress.mac, 6);
+ arp_packet->sender_ip = inf->address.ipv4;
+ grub_memset (arp_packet->recv_mac, 0, 6);
+ arp_packet->recv_ip = proto_addr->ipv4;
/* Target protocol address */
- grub_memcpy (aux, &proto_addr->ipv4, 4);
- grub_memset (&target_hw_addr.mac, 0xff, 6);
+ grub_memset (&target_mac_addr.mac, 0xff, 6);
nbd = nb.data;
- send_ethernet_packet (inf, &nb, target_hw_addr, GRUB_NET_ETHERTYPE_ARP);
+ send_ethernet_packet (inf, &nb, target_mac_addr, GRUB_NET_ETHERTYPE_ARP);
for (i = 0; i < GRUB_NET_TRIES; i++)
{
if (grub_net_link_layer_resolve_check (inf, proto_addr))
if (grub_net_link_layer_resolve_check (inf, proto_addr))
return GRUB_ERR_NONE;
nb.data = nbd;
- send_ethernet_packet (inf, &nb, target_hw_addr, GRUB_NET_ETHERTYPE_ARP);
+ send_ethernet_packet (inf, &nb, target_mac_addr, GRUB_NET_ETHERTYPE_ARP);
}
return GRUB_ERR_NONE;
grub_net_arp_receive (struct grub_net_buff *nb,
struct grub_net_card *card)
{
- struct arphdr *arp_header = (struct arphdr *) nb->data;
- grub_uint8_t *sender_hardware_address;
- grub_uint8_t *target_hardware_address;
+ struct arppkt *arp_packet = (struct arppkt *) nb->data;
grub_net_network_level_address_t sender_addr, target_addr;
- grub_net_link_level_address_t sender_hw_addr;
+ grub_net_link_level_address_t sender_mac_addr;
struct grub_net_network_level_interface *inf;
- grub_uint8_t *sender_protocol_address, *target_protocol_address;
-
- sender_hardware_address =
- (grub_uint8_t *) arp_header + sizeof (*arp_header);
- sender_protocol_address = sender_hardware_address + arp_header->hln;
- target_hardware_address = sender_protocol_address + arp_header->pln;
- target_protocol_address = target_hardware_address + arp_header->hln;
- if (grub_be_to_cpu16 (arp_header->pro) == GRUB_NET_ETHERTYPE_IP
- && arp_header->pln == 4)
- {
- sender_addr.type = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
- target_addr.type = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
- grub_memcpy (&sender_addr.ipv4, sender_protocol_address, 4);
- grub_memcpy (&target_addr.ipv4, target_protocol_address, 4);
- if (grub_memcmp (sender_protocol_address, &pending_req, 4) == 0)
- have_pending = 1;
- }
- else
+
+ if (arp_packet->pro != grub_cpu_to_be16_compile_time (GRUB_NET_ETHERTYPE_IP)
+ || arp_packet->pln != 4 || arp_packet->hln != 6
+ || nb->tail - nb->data < (int) sizeof (*arp_packet))
return GRUB_ERR_NONE;
- sender_hw_addr.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
- grub_memcpy (sender_hw_addr.mac, sender_hardware_address,
- sizeof (sender_hw_addr.mac));
- grub_net_link_layer_add_address (card, &sender_addr, &sender_hw_addr, 1);
+ sender_addr.type = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
+ target_addr.type = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
+ sender_addr.ipv4 = arp_packet->sender_ip;
+ target_addr.ipv4 = arp_packet->recv_ip;
+ if (arp_packet->sender_ip == pending_req)
+ have_pending = 1;
+
+ sender_mac_addr.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
+ grub_memcpy (sender_mac_addr.mac, arp_packet->sender_mac,
+ sizeof (sender_mac_addr.mac));
+ grub_net_link_layer_add_address (card, &sender_addr, &sender_mac_addr, 1);
FOR_NET_NETWORK_LEVEL_INTERFACES (inf)
{
/* Am I the protocol address target? */
if (grub_net_addr_cmp (&inf->address, &target_addr) == 0
- && grub_be_to_cpu16 (arp_header->op) == ARP_REQUEST)
+ && arp_packet->op == grub_cpu_to_be16_compile_time (ARP_REQUEST))
{
grub_net_link_level_address_t target;
- /* We've already checked that pln is either 4 or 16. */
- char tmp[16];
- grub_size_t pln = arp_header->pln;
-
- if (pln > 16)
- pln = 16;
+ struct grub_net_buff nb_reply;
+ struct arppkt *arp_reply;
+ grub_uint8_t arp_data[128];
+ grub_err_t err;
+
+ nb_reply.head = arp_data;
+ nb_reply.end = arp_data + sizeof (arp_data);
+ grub_netbuff_clear (&nb_reply);
+ grub_netbuff_reserve (&nb_reply, 128);
+
+ err = grub_netbuff_push (&nb_reply, sizeof (*arp_packet));
+ if (err)
+ return err;
+
+ arp_reply = (struct arppkt *) nb_reply.data;
+
+ arp_reply->hrd = grub_cpu_to_be16_compile_time (GRUB_NET_ARPHRD_ETHERNET);
+ arp_reply->pro = grub_cpu_to_be16_compile_time (GRUB_NET_ETHERTYPE_IP);
+ arp_reply->pln = 4;
+ arp_reply->hln = 6;
+ arp_reply->op = grub_cpu_to_be16_compile_time (ARP_REPLY);
+ arp_reply->sender_ip = arp_packet->recv_ip;
+ arp_reply->recv_ip = arp_packet->sender_ip;
+ arp_reply->hln = 6;
target.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
- grub_memcpy (target.mac, sender_hardware_address, 6);
- grub_memcpy (target_hardware_address, target.mac, 6);
- grub_memcpy (sender_hardware_address, inf->hwaddress.mac, 6);
-
- grub_memcpy (tmp, sender_protocol_address, pln);
- grub_memcpy (sender_protocol_address, target_protocol_address, pln);
- grub_memcpy (target_protocol_address, tmp, pln);
+ grub_memcpy (target.mac, arp_packet->sender_mac, 6);
+ grub_memcpy (arp_reply->sender_mac, inf->hwaddress.mac, 6);
+ grub_memcpy (arp_reply->recv_mac, arp_packet->sender_mac, 6);
/* Change operation to REPLY and send packet */
- arp_header->op = grub_be_to_cpu16 (ARP_REPLY);
- send_ethernet_packet (inf, nb, target, GRUB_NET_ETHERTYPE_ARP);
+ send_ethernet_packet (inf, &nb_reply, target, GRUB_NET_ETHERTYPE_ARP);
}
}
return GRUB_ERR_NONE;