chiark / gitweb /
udev: really exclude device-mapper from block device ownership event locking
[elogind.git] / src / nss-myhostname / netlink.c
index b1ef912c8ac1d268f683a31b919ab270f8477eb2..b4a464c06a084b7952b65add7cd63b7a72e731f4 100644 (file)
@@ -4,6 +4,7 @@
   This file is part of systemd.
 
   Copyright 2008-2011 Lennart Poettering
+  Copyright 2014 Tom Gundersen
 
   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
   along with systemd; 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 "sd-rtnl.h"
+#include "rtnl-util.h"
+#include "macro.h"
 
 #include "ifconf.h"
 
-#define SEQ 4711
-
-static int read_reply(int fd, struct address **list, unsigned *n_list) {
-        ssize_t bytes;
-        struct cmsghdr *cmsg;
-        struct ucred *ucred;
-        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;
-        struct iovec iov = {
-                .iov_base = &resp,
-                .iov_len = sizeof(resp),
-        };
-        struct msghdr msg = {
-                .msg_name = NULL,
-                .msg_namelen = 0,
-                .msg_iov = &iov,
-                .msg_iovlen = 1,
-                .msg_control = cred_buffer,
-                .msg_controllen = sizeof(cred_buffer),
-                .msg_flags = 0,
-        };
-
-        assert(fd >= 0);
-        assert(list);
-
-        bytes = recvmsg(fd, &msg, 0);
-        if (bytes < 0)
-                return -errno;
-
-        cmsg = CMSG_FIRSTHDR(&msg);
-        if (!cmsg || cmsg->cmsg_type != SCM_CREDENTIALS)
-                return -EIO;
-
-        ucred = (struct ucred*) CMSG_DATA(cmsg);
-        if (ucred->uid != 0 || ucred->pid != 0)
-                return 0;
-
-        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))
-                        return -EIO;
-
-                if (p->nlmsg_seq != SEQ)
-                        continue;
-
-                if (p->nlmsg_type == NLMSG_DONE)
-                        return 1;
+int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) {
+        _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
+        _cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL, *reply = NULL;
+        sd_rtnl_message *m;
+        _cleanup_free_ struct address *list = NULL;
+        struct address *new_list = NULL;
+        unsigned n_list = 0;
+        int r;
 
-                if (p->nlmsg_type == NLMSG_ERROR) {
-                        struct nlmsgerr *nlmsgerr;
+        r = sd_rtnl_open(&rtnl, 0);
+        if (r < 0)
+                return r;
 
-                        nlmsgerr = NLMSG_DATA(p);
-                        return -nlmsgerr->error;
-                }
+        r = sd_rtnl_message_new_addr(rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
+        if (r < 0)
+                return r;
 
-                if (p->nlmsg_type != RTM_NEWADDR)
+        r = sd_rtnl_call(rtnl, req, 0, &reply);
+        if (r < 0)
+                return r;
+        m = reply;
+
+        do {
+                uint16_t type;
+                unsigned char scope;
+                unsigned char flags;
+                unsigned char family;
+                int ifindex;
+                union {
+                        struct in_addr in;
+                        struct in6_addr in6;
+                } address;
+
+                r = sd_rtnl_message_get_errno(m);
+                if (r < 0)
+                        return r;
+
+                r = sd_rtnl_message_get_type(m, &type);
+                if (r < 0)
+                        return r;
+
+                if (type != RTM_NEWADDR)
                         continue;
 
-                ifaddrmsg = NLMSG_DATA(p);
+                r = sd_rtnl_message_addr_get_scope(m, &scope);
+                if (r < 0)
+                        return r;
 
-                if (ifaddrmsg->ifa_family != AF_INET &&
-                    ifaddrmsg->ifa_family != AF_INET6)
+                if (scope == RT_SCOPE_HOST || scope == RT_SCOPE_NOWHERE)
                         continue;
 
-                if (ifaddrmsg->ifa_scope == RT_SCOPE_HOST ||
-                    ifaddrmsg->ifa_scope == RT_SCOPE_NOWHERE)
-                        continue;
+                r = sd_rtnl_message_addr_get_flags(m, &flags);
+                if (r < 0)
+                        return r;
 
-                if (ifaddrmsg->ifa_flags & IFA_F_DEPRECATED)
+                if (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)
+                r = sd_rtnl_message_addr_get_family(m, &family);
+                if (r < 0)
+                        return r;
+
+                switch (family) {
+                case AF_INET:
+                        r = sd_rtnl_message_read_in_addr(m, IFA_LOCAL, &address.in);
+                        if (r < 0) {
+                                r = sd_rtnl_message_read_in_addr(m, IFA_ADDRESS, &address.in);
+                                if (r < 0)
+                                        continue;
+                        }
+                        break;
+                case AF_INET6:
+                        r = sd_rtnl_message_read_in6_addr(m, IFA_LOCAL, &address.in6);
+                        if (r < 0) {
+                                r = sd_rtnl_message_read_in6_addr(m, IFA_ADDRESS, &address.in6);
+                                if (r < 0)
+                                        continue;
+                        }
+                        break;
+                default:
                         continue;
-
-                *list = realloc(*list, (*n_list+1) * sizeof(struct address));
-                if (!*list)
-                        return -ENOMEM;
-
-                (*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)++;
-        }
-
-        return 0;
-}
-
-
-int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) {
-
-        struct {
-                struct nlmsghdr hdr;
-                struct rtgenmsg gen;
-        } req = { {
-                        .nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
-                        .nlmsg_type = RTM_GETADDR,
-                        .nlmsg_flags = NLM_F_REQUEST|NLM_F_DUMP|NLM_F_ACK,
-                        .nlmsg_seq = SEQ,
-                        .nlmsg_pid = 0,
-                }, {
-                        .rtgen_family = AF_UNSPEC,
                 }
-        };
-        int r, on = 1;
-        struct address *list = NULL;
-        unsigned n_list = 0;
-        int fd;
 
-        fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
-        if (fd < 0)
-                return -errno;
+                r = sd_rtnl_message_addr_get_ifindex(m, &ifindex);
+                if (r < 0)
+                        return r;
 
-        if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) {
-                r = -errno;
-                goto finish;
-        }
+                new_list = realloc(list, (n_list+1) * sizeof(struct address));
+                if (!new_list)
+                        return -ENOMEM;
+                else
+                        list = new_list;
 
-        if (send(fd, &req, req.hdr.nlmsg_len, 0) < 0) {
-                r = -errno;
-                goto finish;
-        }
+                assert_cc(sizeof(address) <= 16);
 
-        while((r = read_reply(fd, &list, &n_list)) == 0)
-                ;
+                list[n_list].family = family;
+                list[n_list].scope = scope;
+                memcpy(list[n_list].address, &address, sizeof(address));
+                list[n_list].ifindex = ifindex;
 
-finish:
-        close(fd);
+                n_list++;
 
-        if (r < 0) {
-                free(list);
-                return r;
-        }
+        } while ((m = sd_rtnl_message_next(m)));
 
-        qsort(list, n_list, sizeof(struct address), address_compare);
+        if (n_list)
+                qsort(list, n_list, sizeof(struct address), address_compare);
 
-        *_list = list;
         *_n_list = n_list;
+        *_list = list;
+        list = NULL;
 
         return 0;
 }