root / slirp / arp_table.c @ 8c43a6f0
History | View | Annotate | Download (3.4 kB)
1 |
/*
|
---|---|
2 |
* ARP table
|
3 |
*
|
4 |
* Copyright (c) 2011 AdaCore
|
5 |
*
|
6 |
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
7 |
* of this software and associated documentation files (the "Software"), to deal
|
8 |
* in the Software without restriction, including without limitation the rights
|
9 |
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
10 |
* copies of the Software, and to permit persons to whom the Software is
|
11 |
* furnished to do so, subject to the following conditions:
|
12 |
*
|
13 |
* The above copyright notice and this permission notice shall be included in
|
14 |
* all copies or substantial portions of the Software.
|
15 |
*
|
16 |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
17 |
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
18 |
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
19 |
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
20 |
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
21 |
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
22 |
* THE SOFTWARE.
|
23 |
*/
|
24 |
|
25 |
#include "slirp.h" |
26 |
|
27 |
void arp_table_add(Slirp *slirp, uint32_t ip_addr, uint8_t ethaddr[ETH_ALEN])
|
28 |
{ |
29 |
const uint32_t broadcast_addr =
|
30 |
~slirp->vnetwork_mask.s_addr | slirp->vnetwork_addr.s_addr; |
31 |
ArpTable *arptbl = &slirp->arp_table; |
32 |
int i;
|
33 |
|
34 |
DEBUG_CALL("arp_table_add");
|
35 |
DEBUG_ARG("ip = 0x%x", ip_addr);
|
36 |
DEBUG_ARGS((dfd, " hw addr = %02x:%02x:%02x:%02x:%02x:%02x\n",
|
37 |
ethaddr[0], ethaddr[1], ethaddr[2], |
38 |
ethaddr[3], ethaddr[4], ethaddr[5])); |
39 |
|
40 |
/* Check 0.0.0.0/8 invalid source-only addresses */
|
41 |
if ((ip_addr & htonl(~(0xf << 28))) == 0) { |
42 |
return;
|
43 |
} |
44 |
|
45 |
if (ip_addr == 0xffffffff || ip_addr == broadcast_addr) { |
46 |
/* Do not register broadcast addresses */
|
47 |
return;
|
48 |
} |
49 |
|
50 |
/* Search for an entry */
|
51 |
for (i = 0; i < ARP_TABLE_SIZE; i++) { |
52 |
if (arptbl->table[i].ar_sip == ip_addr) {
|
53 |
/* Update the entry */
|
54 |
memcpy(arptbl->table[i].ar_sha, ethaddr, ETH_ALEN); |
55 |
return;
|
56 |
} |
57 |
} |
58 |
|
59 |
/* No entry found, create a new one */
|
60 |
arptbl->table[arptbl->next_victim].ar_sip = ip_addr; |
61 |
memcpy(arptbl->table[arptbl->next_victim].ar_sha, ethaddr, ETH_ALEN); |
62 |
arptbl->next_victim = (arptbl->next_victim + 1) % ARP_TABLE_SIZE;
|
63 |
} |
64 |
|
65 |
bool arp_table_search(Slirp *slirp, uint32_t ip_addr,
|
66 |
uint8_t out_ethaddr[ETH_ALEN]) |
67 |
{ |
68 |
const uint32_t broadcast_addr =
|
69 |
~slirp->vnetwork_mask.s_addr | slirp->vnetwork_addr.s_addr; |
70 |
ArpTable *arptbl = &slirp->arp_table; |
71 |
int i;
|
72 |
|
73 |
DEBUG_CALL("arp_table_search");
|
74 |
DEBUG_ARG("ip = 0x%x", ip_addr);
|
75 |
|
76 |
/* Check 0.0.0.0/8 invalid source-only addresses */
|
77 |
assert((ip_addr & htonl(~(0xf << 28))) != 0); |
78 |
|
79 |
/* If broadcast address */
|
80 |
if (ip_addr == 0xffffffff || ip_addr == broadcast_addr) { |
81 |
/* return Ethernet broadcast address */
|
82 |
memset(out_ethaddr, 0xff, ETH_ALEN);
|
83 |
return 1; |
84 |
} |
85 |
|
86 |
for (i = 0; i < ARP_TABLE_SIZE; i++) { |
87 |
if (arptbl->table[i].ar_sip == ip_addr) {
|
88 |
memcpy(out_ethaddr, arptbl->table[i].ar_sha, ETH_ALEN); |
89 |
DEBUG_ARGS((dfd, " found hw addr = %02x:%02x:%02x:%02x:%02x:%02x\n",
|
90 |
out_ethaddr[0], out_ethaddr[1], out_ethaddr[2], |
91 |
out_ethaddr[3], out_ethaddr[4], out_ethaddr[5])); |
92 |
return 1; |
93 |
} |
94 |
} |
95 |
|
96 |
return 0; |
97 |
} |