static int interpretLink(struct nlmsghdr *p_hdr, struct ifaddrs **p_resultList) { struct ifinfomsg *l_info = (struct ifinfomsg *)NLMSG_DATA(p_hdr); size_t l_nameSize = 0; size_t l_addrSize = 0; size_t l_dataSize = 0; size_t l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifinfomsg)); struct rtattr *l_rta; for(l_rta = IFLA_RTA(l_info); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize)) { size_t l_rtaDataSize = RTA_PAYLOAD(l_rta); switch(l_rta->rta_type) { case IFLA_ADDRESS: case IFLA_BROADCAST: l_addrSize += NLMSG_ALIGN(calcAddrLen(AF_PACKET, l_rtaDataSize)); break; case IFLA_IFNAME: l_nameSize += NLMSG_ALIGN(l_rtaSize + 1); break; case IFLA_STATS: l_dataSize += NLMSG_ALIGN(l_rtaSize); break; default: break; } } struct ifaddrs *l_entry = malloc(sizeof(struct ifaddrs) + sizeof(int) + l_nameSize + l_addrSize + l_dataSize); if (l_entry == NULL) { return -1; } memset(l_entry, 0, sizeof(struct ifaddrs)); l_entry->ifa_name = ""; char *l_index = ((char *)l_entry) + sizeof(struct ifaddrs); char *l_name = l_index + sizeof(int); char *l_addr = l_name + l_nameSize; char *l_data = l_addr + l_addrSize; // save the interface index so we can look it up when handling the addresses. memcpy(l_index, &l_info->ifi_index, sizeof(int)); l_entry->ifa_flags = l_info->ifi_flags; l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifinfomsg)); for(l_rta = IFLA_RTA(l_info); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize)) { void *l_rtaData = RTA_DATA(l_rta); size_t l_rtaDataSize = RTA_PAYLOAD(l_rta); switch(l_rta->rta_type) { case IFLA_ADDRESS: case IFLA_BROADCAST: { size_t l_addrLen = calcAddrLen(AF_PACKET, l_rtaDataSize); makeSockaddr(AF_PACKET, (struct sockaddr *)l_addr, l_rtaData, l_rtaDataSize); ((struct sockaddr_ll *)l_addr)->sll_ifindex = l_info->ifi_index; ((struct sockaddr_ll *)l_addr)->sll_hatype = l_info->ifi_type; if(l_rta->rta_type == IFLA_ADDRESS) { l_entry->ifa_addr = (struct sockaddr *)l_addr; } else { l_entry->ifa_broadaddr = (struct sockaddr *)l_addr; } l_addr += NLMSG_ALIGN(l_addrLen); break; } case IFLA_IFNAME: strncpy(l_name, l_rtaData, l_rtaDataSize); l_name[l_rtaDataSize] = '\0'; l_entry->ifa_name = l_name; break; case IFLA_STATS: memcpy(l_data, l_rtaData, l_rtaDataSize); l_entry->ifa_data = l_data; break; default: break; } } addToEnd(p_resultList, l_entry); return 0; }
static int interpretAddr(struct nlmsghdr *p_hdr, struct ifaddrs **p_resultList, int p_numLinks) { struct ifaddrmsg *l_info = (struct ifaddrmsg *)NLMSG_DATA(p_hdr); struct ifaddrs *l_interface = findInterface(l_info->ifa_index, p_resultList, p_numLinks); if(l_info->ifa_family == AF_PACKET) { return 0; } size_t l_nameSize = 0; size_t l_addrSize = 0; int l_addedNetmask = 0; size_t l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifaddrmsg)); struct rtattr *l_rta; for(l_rta = IFA_RTA(l_info); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize)) { size_t l_rtaDataSize = RTA_PAYLOAD(l_rta); switch(l_rta->rta_type) { case IFA_ADDRESS: case IFA_LOCAL: if((l_info->ifa_family == AF_INET || l_info->ifa_family == AF_INET6) && !l_addedNetmask) { // make room for netmask l_addrSize += NLMSG_ALIGN(calcAddrLen(l_info->ifa_family, l_rtaDataSize)); l_addedNetmask = 1; } case IFA_BROADCAST: l_addrSize += NLMSG_ALIGN(calcAddrLen(l_info->ifa_family, l_rtaDataSize)); break; case IFA_LABEL: l_nameSize += NLMSG_ALIGN(l_rtaSize + 1); break; default: break; } } struct ifaddrs *l_entry = malloc(sizeof(struct ifaddrs) + l_nameSize + l_addrSize); if (l_entry == NULL) { return -1; } memset(l_entry, 0, sizeof(struct ifaddrs)); l_entry->ifa_name = (l_interface ? l_interface->ifa_name : ""); char *l_name = ((char *)l_entry) + sizeof(struct ifaddrs); char *l_addr = l_name + l_nameSize; l_entry->ifa_flags = l_info->ifa_flags; if(l_interface) { l_entry->ifa_flags |= l_interface->ifa_flags; } l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifaddrmsg)); for(l_rta = IFA_RTA(l_info); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize)) { void *l_rtaData = RTA_DATA(l_rta); size_t l_rtaDataSize = RTA_PAYLOAD(l_rta); switch(l_rta->rta_type) { case IFA_ADDRESS: case IFA_BROADCAST: case IFA_LOCAL: { size_t l_addrLen = calcAddrLen(l_info->ifa_family, l_rtaDataSize); makeSockaddr(l_info->ifa_family, (struct sockaddr *)l_addr, l_rtaData, l_rtaDataSize); if(l_info->ifa_family == AF_INET6) { if(IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)l_rtaData) || IN6_IS_ADDR_MC_LINKLOCAL((struct in6_addr *)l_rtaData)) { ((struct sockaddr_in6 *)l_addr)->sin6_scope_id = l_info->ifa_index; } } if(l_rta->rta_type == IFA_ADDRESS) { // apparently in a point-to-point network IFA_ADDRESS contains the dest address and IFA_LOCAL contains the local address if(l_entry->ifa_addr) { l_entry->ifa_dstaddr = (struct sockaddr *)l_addr; } else { l_entry->ifa_addr = (struct sockaddr *)l_addr; } } else if(l_rta->rta_type == IFA_LOCAL) { if(l_entry->ifa_addr) { l_entry->ifa_dstaddr = l_entry->ifa_addr; } l_entry->ifa_addr = (struct sockaddr *)l_addr; } else { l_entry->ifa_broadaddr = (struct sockaddr *)l_addr; } l_addr += NLMSG_ALIGN(l_addrLen); break; } case IFA_LABEL: strncpy(l_name, l_rtaData, l_rtaDataSize); l_name[l_rtaDataSize] = '\0'; l_entry->ifa_name = l_name; break; default: break; } } if(l_entry->ifa_addr && (l_entry->ifa_addr->sa_family == AF_INET || l_entry->ifa_addr->sa_family == AF_INET6)) { unsigned l_maxPrefix = (l_entry->ifa_addr->sa_family == AF_INET ? 32 : 128); unsigned l_prefix = (l_info->ifa_prefixlen > l_maxPrefix ? l_maxPrefix : l_info->ifa_prefixlen); char l_mask[16] = {0}; unsigned i; for(i=0; i<(l_prefix/8); ++i) { l_mask[i] = 0xff; } if(l_prefix % 8) { l_mask[i] = 0xff << (8 - (l_prefix % 8)); } makeSockaddr(l_entry->ifa_addr->sa_family, (struct sockaddr *)l_addr, l_mask, l_maxPrefix / 8); l_entry->ifa_netmask = (struct sockaddr *)l_addr; } addToEnd(p_resultList, l_entry); return 0; }
static void interpretLink(struct nlmsghdr *p_hdr, struct ifaddrs **p_links, struct ifaddrs **p_resultList) { struct ifinfomsg *l_info = (struct ifinfomsg *)NLMSG_DATA(p_hdr); size_t l_nameSize = 0; size_t l_addrSize = 0; size_t l_dataSize = 0; size_t l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifinfomsg)); struct rtattr *l_rta; for(l_rta = (struct rtattr *)(((char *)l_info) + NLMSG_ALIGN(sizeof(struct ifinfomsg))); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize)) { void *l_rtaData = RTA_DATA(l_rta); size_t l_rtaDataSize = RTA_PAYLOAD(l_rta); switch(l_rta->rta_type) { case IFLA_ADDRESS: case IFLA_BROADCAST: l_addrSize += NLMSG_ALIGN(calcAddrLen(AF_PACKET, l_rtaDataSize)); break; case IFLA_IFNAME: l_nameSize += NLMSG_ALIGN(l_rtaSize + 1); break; case IFLA_STATS: l_dataSize += NLMSG_ALIGN(l_rtaSize); break; default: break; } } struct ifaddrs *l_entry; l_entry = (struct ifaddrs *)malloc(sizeof(struct ifaddrs) + l_nameSize + l_addrSize + l_dataSize); memset(l_entry, 0, sizeof(struct ifaddrs)); l_entry->ifa_name = ""; char *l_name = ((char *)l_entry) + sizeof(struct ifaddrs); char *l_addr = l_name + l_nameSize; char *l_data = l_addr + l_addrSize; l_entry->ifa_flags = l_info->ifi_flags; l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifinfomsg)); for(l_rta = (struct rtattr *)(((char *)l_info) + NLMSG_ALIGN(sizeof(struct ifinfomsg))); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize)) { void *l_rtaData = RTA_DATA(l_rta); size_t l_rtaDataSize = RTA_PAYLOAD(l_rta); switch(l_rta->rta_type) { case IFLA_ADDRESS: case IFLA_BROADCAST: { size_t l_addrLen = calcAddrLen(AF_PACKET, l_rtaDataSize); makeSockaddr(AF_PACKET, (struct sockaddr *)l_addr, l_rtaData, l_rtaDataSize); ((struct sockaddr_ll *)l_addr)->sll_ifindex = l_info->ifi_index; ((struct sockaddr_ll *)l_addr)->sll_hatype = l_info->ifi_type; if(l_rta->rta_type == IFLA_ADDRESS) { l_entry->ifa_addr = (struct sockaddr *)l_addr; } else { l_entry->ifa_broadaddr = (struct sockaddr *)l_addr; } l_addr += NLMSG_ALIGN(l_addrLen); break; } case IFLA_IFNAME: strncpy(l_name, (char *)l_rtaData, l_rtaDataSize); l_name[l_rtaDataSize] = '\0'; l_entry->ifa_name = l_name; break; case IFLA_STATS: memcpy(l_data, l_rtaData, l_rtaDataSize); l_entry->ifa_data = l_data; break; default: break; } } addToEnd(p_resultList, l_entry); p_links[l_info->ifi_index - 1] = l_entry; }