| William A. Kennington III | 7d6fa42 | 2021-02-08 17:04:02 -0800 | [diff] [blame^] | 1 | #include "net_iface.h" |
| 2 | |
| 3 | #include <linux/if_packet.h> |
| 4 | #include <net/ethernet.h> |
| 5 | #include <sys/socket.h> |
| 6 | #include <unistd.h> |
| 7 | |
| 8 | #include <cstdio> |
| 9 | #include <cstring> |
| 10 | #include <stdexcept> |
| 11 | |
| 12 | namespace net |
| 13 | { |
| 14 | |
| 15 | IFaceBase::IFaceBase(const std::string& name) : name_{name} |
| 16 | { |
| 17 | if (name.size() >= IFNAMSIZ) |
| 18 | { |
| 19 | throw std::length_error("Interface name is too long"); |
| 20 | } |
| 21 | } |
| 22 | |
| 23 | int IFaceBase::get_index() const |
| 24 | { |
| 25 | struct ifreq ifr; |
| 26 | std::memset(&ifr, 0, sizeof(ifr)); |
| 27 | int ret = ioctl(SIOCGIFINDEX, &ifr); |
| 28 | if (ret < 0) |
| 29 | { |
| 30 | return ret; |
| 31 | } |
| 32 | |
| 33 | return ifr.ifr_ifindex; |
| 34 | } |
| 35 | |
| 36 | int IFaceBase::set_sock_flags(int sockfd, short flags) const |
| 37 | { |
| 38 | return mod_sock_flags(sockfd, flags, true); |
| 39 | } |
| 40 | |
| 41 | int IFaceBase::clear_sock_flags(int sockfd, short flags) const |
| 42 | { |
| 43 | return mod_sock_flags(sockfd, flags, false); |
| 44 | } |
| 45 | |
| 46 | int IFaceBase::mod_sock_flags(int sockfd, short flags, bool set) const |
| 47 | { |
| 48 | struct ifreq ifr; |
| 49 | std::memset(&ifr, 0, sizeof(ifr)); |
| 50 | |
| 51 | int ret = ioctl_sock(sockfd, SIOCGIFFLAGS, &ifr); |
| 52 | if (ret < 0) |
| 53 | { |
| 54 | return ret; |
| 55 | } |
| 56 | |
| 57 | if (set) |
| 58 | { |
| 59 | ifr.ifr_flags |= flags; |
| 60 | } |
| 61 | else |
| 62 | { |
| 63 | ifr.ifr_flags &= ~flags; |
| 64 | } |
| 65 | return ioctl_sock(sockfd, SIOCSIFFLAGS, &ifr); |
| 66 | } |
| 67 | |
| 68 | int IFace::ioctl_sock(int sockfd, int request, struct ifreq* ifr) const |
| 69 | { |
| 70 | if (ifr == nullptr) |
| 71 | { |
| 72 | return -1; |
| 73 | } |
| 74 | |
| 75 | /* Avoid string truncation. */ |
| 76 | size_t len = name_.length(); |
| 77 | if (len + 1 >= sizeof(ifr->ifr_name)) |
| 78 | { |
| 79 | return -1; |
| 80 | } |
| 81 | |
| 82 | std::memcpy(ifr->ifr_name, name_.c_str(), len); |
| 83 | ifr->ifr_name[len] = 0; |
| 84 | |
| 85 | return ::ioctl(sockfd, request, ifr); |
| 86 | } |
| 87 | |
| 88 | int IFace::bind_sock(int sockfd, struct sockaddr_ll* saddr) const |
| 89 | { |
| 90 | if (saddr == nullptr) |
| 91 | { |
| 92 | return -1; |
| 93 | } |
| 94 | |
| 95 | saddr->sll_ifindex = get_index(); |
| 96 | |
| 97 | return bind(sockfd, reinterpret_cast<struct sockaddr*>(saddr), |
| 98 | sizeof(*saddr)); |
| 99 | } |
| 100 | |
| 101 | int IFace::ioctl(int request, struct ifreq* ifr) const |
| 102 | { |
| 103 | if (ifr == nullptr) |
| 104 | { |
| 105 | return -1; |
| 106 | } |
| 107 | |
| 108 | int tempsock = socket(AF_INET, SOCK_DGRAM, 0); |
| 109 | if (tempsock < 0) |
| 110 | { |
| 111 | return tempsock; |
| 112 | } |
| 113 | |
| 114 | int ret = ioctl_sock(tempsock, request, ifr); |
| 115 | close(tempsock); |
| 116 | |
| 117 | return ret; |
| 118 | } |
| 119 | |
| 120 | } // namespace net |