diff options
Diffstat (limited to 'src/shared')
| -rw-r--r-- | src/shared/arp.c | 126 | ||||
| -rwxr-xr-x | src/shared/arp.h | 47 |
2 files changed, 173 insertions, 0 deletions
diff --git a/src/shared/arp.c b/src/shared/arp.c new file mode 100644 index 00000000..6cd611f2 --- /dev/null +++ b/src/shared/arp.c @@ -0,0 +1,126 @@ +/* + * + * Connection Manager + * + * based on IPv4 Local Link library with GLib integration, + * Copyright (C) 2009-2010 Aldebaran Robotics. All rights reserved. + * + * Copyright (C) 2018 Commend International. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program 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 General Public License for more details. + * + */ +#include <string.h> +#include <stdlib.h> +#include <errno.h> +#include <unistd.h> + +#include <sys/time.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <netpacket/packet.h> +#include <net/ethernet.h> +#include <netinet/if_ether.h> +#include <net/if_arp.h> + +#include <arpa/inet.h> + +#include "src/shared/arp.h" +#include "src/connman.h" + +int arp_send_packet(uint8_t* source_eth, uint32_t source_ip, + uint32_t target_ip, int ifindex) +{ + struct sockaddr_ll dest; + struct ether_arp p; + uint32_t ip_source; + uint32_t ip_target; + int fd, n; + + fd = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC, 0); + if (fd < 0) + return -errno; + + memset(&dest, 0, sizeof(dest)); + memset(&p, 0, sizeof(p)); + + dest.sll_family = AF_PACKET; + dest.sll_protocol = htons(ETH_P_ARP); + dest.sll_ifindex = ifindex; + dest.sll_halen = ETH_ALEN; + memset(dest.sll_addr, 0xFF, ETH_ALEN); + if (bind(fd, (struct sockaddr *)&dest, sizeof(dest)) < 0) { + int err = errno; + close(fd); + return -err; + } + + ip_source = htonl(source_ip); + ip_target = htonl(target_ip); + p.arp_hrd = htons(ARPHRD_ETHER); + p.arp_pro = htons(ETHERTYPE_IP); + p.arp_hln = ETH_ALEN; + p.arp_pln = 4; + p.arp_op = htons(ARPOP_REQUEST); + + memcpy(&p.arp_sha, source_eth, ETH_ALEN); + memcpy(&p.arp_spa, &ip_source, sizeof(p.arp_spa)); + memcpy(&p.arp_tpa, &ip_target, sizeof(p.arp_tpa)); + + n = sendto(fd, &p, sizeof(p), 0, + (struct sockaddr*) &dest, sizeof(dest)); + if (n < 0) + n = -errno; + + close(fd); + + return n; +} + +int arp_socket(int ifindex) +{ + int fd; + struct sockaddr_ll sock; + + fd = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC, 0); + if (fd < 0) + return fd; + + memset(&sock, 0, sizeof(sock)); + + sock.sll_family = AF_PACKET; + sock.sll_protocol = htons(ETH_P_ARP); + sock.sll_ifindex = ifindex; + + if (bind(fd, (struct sockaddr *) &sock, sizeof(sock)) != 0) { + int err = errno; + close(fd); + return -err; + } + + return fd; +} + +/** + * Return a random link local IP (in host byte order) + */ +uint32_t arp_random_ip(void) +{ + unsigned tmp; + + do { + uint64_t rand; + __connman_util_get_random(&rand); + tmp = rand; + tmp = tmp & IN_CLASSB_HOST; + } while (tmp > (IN_CLASSB_HOST - 0x0200)); + + return (LINKLOCAL_ADDR + 0x0100) + tmp; +} diff --git a/src/shared/arp.h b/src/shared/arp.h new file mode 100755 index 00000000..03e2168c --- /dev/null +++ b/src/shared/arp.h @@ -0,0 +1,47 @@ +/* + * + * Connection Manager + * + * based on IPv4 Local Link library with GLib integration, + * Copyright (C) 2009-2010 Aldebaran Robotics. All rights reserved. + * + * Copyright (C) 2018 Commend International. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program 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 General Public License for more details. + * + */ + +#ifndef SHARED_ARP_H +#define SHARED_ARP_H + +#include <stdint.h> + +/* IPv4 Link-Local (RFC 3927), IPv4 Address Conflict Detection (RFC 5227) */ +#define PROBE_WAIT 1 +#define PROBE_NUM 3 +#define PROBE_MIN 1 +#define PROBE_MAX 2 +#define ANNOUNCE_WAIT 2 +#define ANNOUNCE_NUM 2 +#define ANNOUNCE_INTERVAL 2 +#define MAX_CONFLICTS 10 +#define RATE_LIMIT_INTERVAL 60 +#define DEFEND_INTERVAL 10 + +/* 169.254.0.0 */ +#define LINKLOCAL_ADDR 0xa9fe0000 + +int arp_send_packet(uint8_t* source_eth, uint32_t source_ip, + uint32_t target_ip, int ifindex); +int arp_socket(int ifindex); + +uint32_t arp_random_ip(void); + +#endif |