1 /* $NetBSD: config.c,v 1.6 1995/12/10 10:06:58 mycroft Exp $ */ 2 3 /* 4 * The mrouted program is covered by the license in the accompanying file 5 * named "LICENSE". Use of the mrouted program represents acceptance of 6 * the terms and conditions listed in that file. 7 * 8 * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of 9 * Leland Stanford Junior University. 10 */ 11 12 #include "defs.h" 13 #include <net/if.h> 14 #include <ifaddrs.h> 15 16 17 /* 18 * Query the kernel to find network interfaces that are multicast-capable 19 * and install them in the uvifs array. 20 */ 21 void 22 config_vifs_from_kernel(void) 23 { 24 struct ifaddrs *ifa, *ifap; 25 struct uvif *v; 26 vifi_t vifi; 27 u_int32_t addr, mask, subnet; 28 short flags; 29 30 if (getifaddrs(&ifap) < 0) 31 logit(LOG_ERR, errno, "getifaddrs"); 32 33 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 34 /* 35 * Ignore any interface for an address family other than IP. 36 */ 37 if (ifa->ifa_addr->sa_family != AF_INET) 38 continue; 39 40 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr; 41 42 /* 43 * Ignore loopback interfaces and interfaces that do not support 44 * multicast. 45 */ 46 flags = ifa->ifa_flags; 47 if ((flags & (IFF_LOOPBACK|IFF_MULTICAST)) != IFF_MULTICAST) 48 continue; 49 50 /* 51 * Ignore any interface whose address and mask do not define a 52 * valid subnet number, or whose address is of the form {subnet,0} 53 * or {subnet,-1}. 54 */ 55 mask = ((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr.s_addr; 56 subnet = addr & mask; 57 if (!inet_valid_subnet(subnet, mask) || 58 addr == subnet || 59 addr == (subnet | ~mask)) { 60 logit(LOG_WARNING, 0, 61 "ignoring %s, has invalid address (%s) and/or mask (%s)", 62 ifa->ifa_name, inet_fmt(addr, s1), inet_fmt(mask, s2)); 63 continue; 64 } 65 66 /* 67 * Ignore any interface that is connected to the same subnet as 68 * one already installed in the uvifs array. 69 */ 70 for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { 71 if ((addr & v->uv_subnetmask) == v->uv_subnet || 72 (v->uv_subnet & mask) == subnet) { 73 logit(LOG_WARNING, 0, "ignoring %s, same subnet as %s", 74 ifa->ifa_name, v->uv_name); 75 break; 76 } 77 } 78 if (vifi != numvifs) 79 continue; 80 81 /* 82 * If there is room in the uvifs array, install this interface. 83 */ 84 if (numvifs == MAXVIFS) { 85 logit(LOG_WARNING, 0, "too many vifs, ignoring %s", ifa->ifa_name); 86 continue; 87 } 88 v = &uvifs[numvifs]; 89 v->uv_flags = 0; 90 v->uv_metric = DEFAULT_METRIC; 91 v->uv_rate_limit = DEFAULT_PHY_RATE_LIMIT; 92 v->uv_threshold = DEFAULT_THRESHOLD; 93 v->uv_lcl_addr = addr; 94 v->uv_rmt_addr = 0; 95 v->uv_subnet = subnet; 96 v->uv_subnetmask = mask; 97 v->uv_subnetbcast = subnet | ~mask; 98 strlcpy(v->uv_name, ifa->ifa_name, sizeof(v->uv_name)); 99 v->uv_groups = NULL; 100 v->uv_neighbors = NULL; 101 v->uv_acl = NULL; 102 v->uv_addrs = NULL; 103 104 logit(LOG_INFO,0,"installing %s (%s on subnet %s) as vif #%u - rate=%d", 105 v->uv_name, inet_fmt(addr, s1), inet_fmts(subnet, mask, s2), 106 numvifs, v->uv_rate_limit); 107 108 ++numvifs; 109 110 /* 111 * If the interface is not yet up, set the vifs_down flag to 112 * remind us to check again later. 113 */ 114 if (!(flags & IFF_UP)) { 115 v->uv_flags |= VIFF_DOWN; 116 vifs_down = TRUE; 117 } 118 } 119 120 freeifaddrs(ifap); 121 } 122