From 996d16975b4d802335188a3be2bbc3635c1287f3 Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Tue, 18 Aug 2015 15:37:43 +0200 Subject: sd-ipv4ll: filter out unwanted ARP packets in the kernel We currently process every ARP packet, but we should only care about the ones relating to our IP address. Also rename ipv4ll helpers to apr-utils.[ch], and rework the helpers a bit. --- src/libsystemd-network/ipv4ll-network.c | 91 --------------------------------- 1 file changed, 91 deletions(-) delete mode 100644 src/libsystemd-network/ipv4ll-network.c (limited to 'src/libsystemd-network/ipv4ll-network.c') diff --git a/src/libsystemd-network/ipv4ll-network.c b/src/libsystemd-network/ipv4ll-network.c deleted file mode 100644 index 93ffed408f..0000000000 --- a/src/libsystemd-network/ipv4ll-network.c +++ /dev/null @@ -1,91 +0,0 @@ -/*** - This file is part of systemd. - - Copyright (C) 2014 Axis Communications AB. All rights reserved. - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see . -***/ - -#include - -#include "util.h" -#include "ipv4ll-internal.h" - -int arp_network_send_raw_socket(int fd, const union sockaddr_union *link, - const struct ether_arp *arp) { - int r; - - assert(arp); - assert(link); - assert(fd >= 0); - - r = sendto(fd, arp, sizeof(struct ether_arp), 0, &link->sa, sizeof(link->ll)); - if (r < 0) - return -errno; - - return 0; -} - -int arp_network_bind_raw_socket(int ifindex, union sockaddr_union *link) { - - static const struct sock_filter filter[] = { - BPF_STMT(BPF_LD + BPF_W + BPF_LEN, 0), /* A <- packet length */ - BPF_JUMP(BPF_JMP + BPF_JGE + BPF_K, sizeof(struct ether_arp), 1, 0), /* packet >= arp packet ? */ - BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */ - BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(struct ether_arp, ea_hdr.ar_hrd)), /* A <- header */ - BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ARPHRD_ETHER, 1, 0), /* header == ethernet ? */ - BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */ - BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(struct ether_arp, ea_hdr.ar_pro)), /* A <- protocol */ - BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ETHERTYPE_IP, 1, 0), /* protocol == IP ? */ - BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */ - BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(struct ether_arp, ea_hdr.ar_op)), /* A <- operation */ - BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ARPOP_REQUEST, 0, 1), /* protocol == request ? */ - BPF_STMT(BPF_RET + BPF_K, 65535), /* return all */ - BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ARPOP_REPLY, 0, 1), /* protocol == reply ? */ - BPF_STMT(BPF_RET + BPF_K, 65535), /* return all */ - BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */ - }; - struct sock_fprog fprog = { - .len = ELEMENTSOF(filter), - .filter = (struct sock_filter*) filter - }; - _cleanup_close_ int s = -1; - int r; - - assert(ifindex > 0); - assert(link); - - s = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 0); - if (s < 0) - return -errno; - - r = setsockopt(s, SOL_SOCKET, SO_ATTACH_FILTER, &fprog, sizeof(fprog)); - if (r < 0) - return -errno; - - link->ll.sll_family = AF_PACKET; - link->ll.sll_protocol = htons(ETH_P_ARP); - link->ll.sll_ifindex = ifindex; - link->ll.sll_halen = ETH_ALEN; - memset(link->ll.sll_addr, 0xff, ETH_ALEN); - - r = bind(s, &link->sa, sizeof(link->ll)); - if (r < 0) - return -errno; - - r = s; - s = -1; - - return r; -} -- cgit v1.2.3-54-g00ecf