diff options
Diffstat (limited to 'avahi-autoipd/iface-linux.c')
| -rw-r--r-- | avahi-autoipd/iface-linux.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/avahi-autoipd/iface-linux.c b/avahi-autoipd/iface-linux.c new file mode 100644 index 0000000..c2f24df --- /dev/null +++ b/avahi-autoipd/iface-linux.c @@ -0,0 +1,297 @@ +/* $Id$ */ + +/*** + This file is part of avahi. + + avahi 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. + + avahi 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 avahi; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 + USA. +***/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <sys/socket.h> +#include <errno.h> +#include <string.h> +#include <unistd.h> +#include <arpa/inet.h> + +#include <linux/types.h> +#include <linux/netlink.h> +#include <linux/rtnetlink.h> +#include <linux/if.h> +#include <linux/if_arp.h> + +#include <libdaemon/dlog.h> + +#include <avahi-common/llist.h> +#include <avahi-common/malloc.h> + +#include "iface.h" + +static int fd = -1; +static int ifindex = -1; + +typedef struct Address Address; + +struct Address { + uint32_t address; + AVAHI_LLIST_FIELDS(Address, addresses); +}; + +AVAHI_LLIST_HEAD(Address, addresses) = NULL; + +int iface_init(int i) { + struct sockaddr_nl addr; + + if ((fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE)) < 0) { + daemon_log(LOG_ERR, "socket(PF_NETLINK): %s", strerror(errno)); + goto fail; + } + + memset(&addr, 0, sizeof(addr)); + addr.nl_family = AF_NETLINK; + addr.nl_groups = RTMGRP_LINK|RTMGRP_IPV4_IFADDR; + addr.nl_pid = getpid(); + + if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { + daemon_log(LOG_ERR, "bind(): %s", strerror(errno)); + goto fail; + } + + ifindex = i; + + return fd; + +fail: + if (fd >= 0) { + close(fd); + fd = -1; + } + + return -1; +} + +static int process_nlmsg(struct nlmsghdr *n) { + assert(n); + + if (n->nlmsg_type == RTM_NEWLINK || n->nlmsg_type == RTM_DELLINK) { + /* A link appeared or was removed */ + + struct ifinfomsg *ifi; + ifi = NLMSG_DATA(n); + + if (ifi->ifi_family != AF_UNSPEC || ifi->ifi_index != ifindex) + return 0; + + if (n->nlmsg_type == RTM_DELLINK) { + daemon_log(LOG_ERR, "Interface vanished."); + return -1; + } + + assert(n->nlmsg_type == RTM_NEWLINK); + + if ((ifi->ifi_flags & IFF_LOOPBACK) || + (ifi->ifi_flags & IFF_NOARP) || + !(ifi->ifi_flags & IFF_UP) || + ifi->ifi_type != ARPHRD_ETHER) { + daemon_log(LOG_ERR, "Interface not suitable."); + return -1; + } + + } else if (n->nlmsg_type == RTM_NEWADDR || n->nlmsg_type == RTM_DELADDR) { + + /* An address was added or removed */ + + struct rtattr *a = NULL; + struct ifaddrmsg *ifa; + int l; + uint32_t address = 0; + Address *i; + char buf[32]; + + ifa = NLMSG_DATA(n); + + if (ifa->ifa_family != AF_INET || ifa->ifa_index != ifindex) + return 0; + + l = NLMSG_PAYLOAD(n, sizeof(*ifa)); + a = IFLA_RTA(ifa); + + while(RTA_OK(a, l)) { + + switch(a->rta_type) { + case IFA_LOCAL: + case IFA_ADDRESS: + assert(RTA_PAYLOAD(a) == 4); + memcpy(&address, RTA_DATA(a), sizeof(uint32_t)); + break; + } + + a = RTA_NEXT(a, l); + } + + daemon_log(LOG_INFO, "%s", inet_ntop(AF_INET, &address, buf, sizeof(buf))); + + if (!address || is_ll_address(address)) + return 0; + + for (i = addresses; i; i = i->addresses_next) + if (i->address == address) + break; + + if (n->nlmsg_type == RTM_DELADDR && i) { + AVAHI_LLIST_REMOVE(Address, addresses, addresses, i); + avahi_free(i); + } if (n->nlmsg_type == RTM_NEWADDR && !i) { + i = avahi_new(Address, 1); + i->address = address; + AVAHI_LLIST_PREPEND(Address, addresses, addresses, i); + } + } + + return 0; +} + +static int process_response(int wait_for_done, unsigned seq) { + assert(fd >= 0); + + do { + size_t bytes; + ssize_t r; + char replybuf[2048]; + struct nlmsghdr *p = (struct nlmsghdr *) replybuf; + + if ((r = recv(fd, replybuf, sizeof(replybuf), 0)) < 0) { + daemon_log(LOG_ERR, "recv() failed: %s", strerror(errno)); + return -1; + } + + bytes = (size_t) r; + + for (; bytes > 0; p = NLMSG_NEXT(p, bytes)) { + + if (!NLMSG_OK(p, bytes) || bytes < sizeof(struct nlmsghdr) || bytes < p->nlmsg_len) { + daemon_log(LOG_ERR, "Netlink packet too small."); + return -1; + } + + if (p->nlmsg_type == NLMSG_DONE && wait_for_done && p->nlmsg_seq == seq) + return 0; + + if (p->nlmsg_type == NLMSG_ERROR) { + struct nlmsgerr *e = (struct nlmsgerr *) NLMSG_DATA (p); + + if (e->error) { + daemon_log(LOG_ERR, "Netlink error: %s", strerror(-e->error)); + return -1; + } + } + + if ((pid_t) p->nlmsg_pid != getpid()) + continue; + + if (process_nlmsg(p) < 0) + return -1; + } + } while (wait_for_done); + + return 0; +} + +int iface_get_initial_state(State *state) { + struct nlmsghdr *n; + struct ifinfomsg *ifi; + struct ifaddrmsg *ifa; + uint8_t req[1024]; + int seq = 0; + + assert(fd >= 0); + assert(state); + + memset(&req, 0, sizeof(req)); + n = (struct nlmsghdr*) req; + n->nlmsg_len = NLMSG_LENGTH(sizeof(*ifi)); + n->nlmsg_type = RTM_GETLINK; + n->nlmsg_seq = seq; + n->nlmsg_flags = NLM_F_MATCH|NLM_F_REQUEST|NLM_F_ACK; + n->nlmsg_pid = 0; + + ifi = NLMSG_DATA(n); + ifi->ifi_family = AF_UNSPEC; + ifi->ifi_change = -1; + + if (send(fd, n, n->nlmsg_len, 0) < 0) { + daemon_log(LOG_ERR, "send(): %s", strerror(errno)); + return -1; + } + + if (process_response(1, 0) < 0) + return -1; + + n->nlmsg_type = RTM_GETADDR; + n->nlmsg_len = NLMSG_LENGTH(sizeof(*ifa)); + n->nlmsg_seq = ++seq; + + ifa = NLMSG_DATA(n); + ifa->ifa_family = AF_INET; + ifa->ifa_index = ifindex; + + if (send(fd, n, n->nlmsg_len, 0) < 0) { + daemon_log(LOG_ERR, "send(): %s", strerror(errno)); + return -1; + } + + if (process_response(1, seq) < 0) + return -1; + + *state = addresses ? STATE_SLEEPING : STATE_START; + + return 0; +} + +int iface_process(Event *event) { + int b; + assert(fd >= 0); + + b = !!addresses; + + if (process_response(0, 0) < 0) + return -1; + + if (b && !!addresses) + *event = EVENT_ROUTABLE_ADDR_UNCONFIGURED; + else if (!b && addresses) + *event = EVENT_ROUTABLE_ADDR_CONFIGURED; + + return 0; +} + +void iface_done(void) { + Address *a; + + if (fd >= 0) { + close(fd); + fd = -1; + } + + while ((a = addresses)) { + AVAHI_LLIST_REMOVE(Address, addresses, addresses, a); + avahi_free(a); + } +} + + |