9pfs: fix crash when fsdev is missing
[qemu.git] / slirp / ndp_table.c
1 /*
2 * Copyright (c) 2013
3 * Guillaume Subiron, Yann Bordenave, Serigne Modou Wagne.
4 */
5
6 #include "qemu/osdep.h"
7 #include "qemu-common.h"
8 #include "slirp.h"
9
10 void ndp_table_add(Slirp *slirp, struct in6_addr ip_addr,
11 uint8_t ethaddr[ETH_ALEN])
12 {
13 NdpTable *ndp_table = &slirp->ndp_table;
14 int i;
15
16 DEBUG_CALL("ndp_table_add");
17 #if !defined(_WIN32) || (_WIN32_WINNT >= 0x0600)
18 char addrstr[INET6_ADDRSTRLEN];
19 inet_ntop(AF_INET6, &(ip_addr), addrstr, INET6_ADDRSTRLEN);
20 DEBUG_ARG("ip = %s", addrstr);
21 #endif
22 DEBUG_ARGS((dfd, " hw addr = %02x:%02x:%02x:%02x:%02x:%02x\n",
23 ethaddr[0], ethaddr[1], ethaddr[2],
24 ethaddr[3], ethaddr[4], ethaddr[5]));
25
26 if (IN6_IS_ADDR_MULTICAST(&ip_addr) || IN6_IS_ADDR_UNSPECIFIED(&ip_addr)) {
27 /* Do not register multicast or unspecified addresses */
28 DEBUG_CALL(" abort: do not register multicast or unspecified address");
29 return;
30 }
31
32 /* Search for an entry */
33 for (i = 0; i < NDP_TABLE_SIZE; i++) {
34 if (in6_equal(&ndp_table->table[i].ip_addr, &ip_addr)) {
35 DEBUG_CALL(" already in table: update the entry");
36 /* Update the entry */
37 memcpy(ndp_table->table[i].eth_addr, ethaddr, ETH_ALEN);
38 return;
39 }
40 }
41
42 /* No entry found, create a new one */
43 DEBUG_CALL(" create new entry");
44 ndp_table->table[ndp_table->next_victim].ip_addr = ip_addr;
45 memcpy(ndp_table->table[ndp_table->next_victim].eth_addr,
46 ethaddr, ETH_ALEN);
47 ndp_table->next_victim = (ndp_table->next_victim + 1) % NDP_TABLE_SIZE;
48 }
49
50 bool ndp_table_search(Slirp *slirp, struct in6_addr ip_addr,
51 uint8_t out_ethaddr[ETH_ALEN])
52 {
53 NdpTable *ndp_table = &slirp->ndp_table;
54 int i;
55
56 DEBUG_CALL("ndp_table_search");
57 #if !defined(_WIN32) || (_WIN32_WINNT >= 0x0600)
58 char addrstr[INET6_ADDRSTRLEN];
59 inet_ntop(AF_INET6, &(ip_addr), addrstr, INET6_ADDRSTRLEN);
60 DEBUG_ARG("ip = %s", addrstr);
61 #endif
62
63 assert(!IN6_IS_ADDR_UNSPECIFIED(&ip_addr));
64
65 /* Multicast address: fec0::abcd:efgh/8 -> 33:33:ab:cd:ef:gh */
66 if (IN6_IS_ADDR_MULTICAST(&ip_addr)) {
67 out_ethaddr[0] = 0x33; out_ethaddr[1] = 0x33;
68 out_ethaddr[2] = ip_addr.s6_addr[12];
69 out_ethaddr[3] = ip_addr.s6_addr[13];
70 out_ethaddr[4] = ip_addr.s6_addr[14];
71 out_ethaddr[5] = ip_addr.s6_addr[15];
72 DEBUG_ARGS((dfd, " multicast addr = %02x:%02x:%02x:%02x:%02x:%02x\n",
73 out_ethaddr[0], out_ethaddr[1], out_ethaddr[2],
74 out_ethaddr[3], out_ethaddr[4], out_ethaddr[5]));
75 return 1;
76 }
77
78 for (i = 0; i < NDP_TABLE_SIZE; i++) {
79 if (in6_equal(&ndp_table->table[i].ip_addr, &ip_addr)) {
80 memcpy(out_ethaddr, ndp_table->table[i].eth_addr, ETH_ALEN);
81 DEBUG_ARGS((dfd, " found hw addr = %02x:%02x:%02x:%02x:%02x:%02x\n",
82 out_ethaddr[0], out_ethaddr[1], out_ethaddr[2],
83 out_ethaddr[3], out_ethaddr[4], out_ethaddr[5]));
84 return 1;
85 }
86 }
87
88 DEBUG_CALL(" ip not found in table");
89 return 0;
90 }