--- /dev/null
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of nss-myhostname.
+
+ Copyright 2008-2011 Lennart Poettering
+
+ nss-myhostname 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.
+
+ nss-myhostname 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 nss-myhostname; If not, see
+ <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <asm/types.h>
+#include <inttypes.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+#include <limits.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <stdlib.h>
+
+#include "ifconf.h"
+
+int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) {
+
+ struct {
+ struct nlmsghdr hdr;
+ struct rtgenmsg gen;
+ } req;
+ struct rtgenmsg *gen;
+ int fd, r, on = 1;
+ uint32_t seq = 4711;
+ struct address *list = NULL;
+ unsigned n_list = 0;
+
+ fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
+ if (fd < 0)
+ return -errno;
+
+ if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ memset(&req, 0, sizeof(req));
+ req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
+ req.hdr.nlmsg_type = RTM_GETADDR;
+ req.hdr.nlmsg_flags = NLM_F_REQUEST|NLM_F_DUMP|NLM_F_ACK;
+ req.hdr.nlmsg_seq = seq;
+ req.hdr.nlmsg_pid = 0;
+
+ gen = NLMSG_DATA(&req.hdr);
+ gen->rtgen_family = AF_UNSPEC;
+
+ if (send(fd, &req, req.hdr.nlmsg_len, 0) < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ for (;;) {
+ ssize_t bytes;
+ struct msghdr msg;
+ struct cmsghdr *cmsg;
+ struct ucred *ucred;
+ struct iovec iov;
+ struct nlmsghdr *p;
+ uint8_t cred_buffer[CMSG_SPACE(sizeof(struct ucred))];
+ struct {
+ struct nlmsghdr hdr;
+ struct ifaddrmsg ifaddrmsg;
+ uint8_t payload[16*1024];
+ } resp;
+
+ memset(&iov, 0, sizeof(iov));
+ iov.iov_base = &resp;
+ iov.iov_len = sizeof(resp);
+
+ memset(&msg, 0, sizeof(msg));
+ msg.msg_name = NULL;
+ msg.msg_namelen = 0;
+ msg.msg_iov = &iov;
+ msg.msg_iovlen = 1;
+ msg.msg_control = cred_buffer;
+ msg.msg_controllen = sizeof(cred_buffer);
+ msg.msg_flags = 0;
+
+ bytes = recvmsg(fd, &msg, 0);
+ if (bytes < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ cmsg = CMSG_FIRSTHDR(&msg);
+ if (!cmsg || cmsg->cmsg_type != SCM_CREDENTIALS) {
+ r = -EIO;
+ goto finish;
+ }
+
+ ucred = (struct ucred*) CMSG_DATA(cmsg);
+ if (ucred->uid != 0 || ucred->pid != 0)
+ continue;
+
+ for (p = &resp.hdr; bytes > 0; p = NLMSG_NEXT(p, bytes)) {
+ struct ifaddrmsg *ifaddrmsg;
+ struct rtattr *a;
+ size_t l;
+ void *local = NULL, *address = NULL;
+
+ if (!NLMSG_OK(p, (size_t) bytes)) {
+ r = -EIO;
+ goto finish;
+ }
+
+ if (p->nlmsg_seq != seq)
+ continue;
+
+ if (p->nlmsg_type == NLMSG_DONE) {
+ r = 0;
+ goto finish;
+ }
+
+ if (p->nlmsg_type == NLMSG_ERROR) {
+ struct nlmsgerr *nlmsgerr;
+
+ nlmsgerr = NLMSG_DATA(p);
+ r = -nlmsgerr->error;
+ goto finish;
+ }
+
+ if (p->nlmsg_type != RTM_NEWADDR)
+ continue;
+
+ ifaddrmsg = NLMSG_DATA(p);
+
+ if (ifaddrmsg->ifa_family != AF_INET &&
+ ifaddrmsg->ifa_family != AF_INET6)
+ continue;
+
+ if (ifaddrmsg->ifa_scope == RT_SCOPE_HOST ||
+ ifaddrmsg->ifa_scope == RT_SCOPE_NOWHERE)
+ continue;
+
+ if (ifaddrmsg->ifa_flags & IFA_F_DEPRECATED)
+ continue;
+
+ l = NLMSG_PAYLOAD(p, sizeof(struct ifaddrmsg));
+ a = IFA_RTA(ifaddrmsg);
+
+ while (RTA_OK(a, l)) {
+
+ if (a->rta_type == IFA_ADDRESS)
+ address = RTA_DATA(a);
+ else if (a->rta_type == IFA_LOCAL)
+ local = RTA_DATA(a);
+
+ a = RTA_NEXT(a, l);
+ }
+
+ if (local)
+ address = local;
+
+ if (!address)
+ continue;
+
+ list = realloc(list, (n_list+1) * sizeof(struct address));
+ if (!list) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ list[n_list].family = ifaddrmsg->ifa_family;
+ list[n_list].scope = ifaddrmsg->ifa_scope;
+ memcpy(list[n_list].address, address, ifaddrmsg->ifa_family == AF_INET ? 4 : 16);
+ list[n_list].ifindex = ifaddrmsg->ifa_index;
+
+ n_list++;
+ }
+ }
+
+finish:
+ close(fd);
+
+ if (r < 0)
+ free(list);
+ else {
+ qsort(list, n_list, sizeof(struct address), address_compare);
+
+ *_list = list;
+ *_n_list = n_list;
+ }
+
+ return r;
+}
~ianmdlvl / elogind.git / blobdiff