for (;;) {
ssize_t l;
- if ((l = sendto(fd, buf, buf_len, flags, sa, sa_len)) >= 0)
+ l = sendto(fd, buf, buf_len, flags, sa, sa_len);
+ if (l >= 0)
return l;
if (errno != EINTR)
for (;;) {
ssize_t l;
- if ((l = recvfrom(fd, buf, buf_len, flags, sa, sa_len)) >= 0)
+ l = recvfrom(fd, buf, buf_len, flags, sa, sa_len);
+ if (l >= 0)
return l;
if (errno != EINTR)
union {
struct sockaddr sa;
struct sockaddr_nl nl;
- } sa;
+ } sa = {
+ .nl.nl_family = AF_NETLINK,
+ };
+
union {
struct nlmsghdr header;
uint8_t buf[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
NLMSG_ALIGN(sizeof(struct ifaddrmsg)) +
RTA_LENGTH(sizeof(struct in6_addr))];
- } request;
+ } request = {
+ .header.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
+ .header.nlmsg_type = RTM_NEWADDR,
+ .header.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_ACK,
+ .header.nlmsg_seq = *requests + 1,
+ };
struct ifaddrmsg *ifaddrmsg;
uint32_t ipv4_address = htonl(INADDR_LOOPBACK);
int r;
- zero(request);
-
- request.header.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
- request.header.nlmsg_type = RTM_NEWADDR;
- request.header.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_ACK;
- request.header.nlmsg_seq = *requests + 1;
-
ifaddrmsg = NLMSG_DATA(&request.header);
ifaddrmsg->ifa_family = AF_INET;
ifaddrmsg->ifa_prefixlen = 8;
ifaddrmsg->ifa_scope = RT_SCOPE_HOST;
ifaddrmsg->ifa_index = if_loopback;
- if ((r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL, &ipv4_address, sizeof(ipv4_address))) < 0)
+ r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL,
+ &ipv4_address, sizeof(ipv4_address));
+ if (r < 0)
return r;
- zero(sa);
- sa.nl.nl_family = AF_NETLINK;
-
if (sendto_loop(fd, &request, request.header.nlmsg_len, 0, &sa.sa, sizeof(sa)) < 0)
return -errno;
(*requests)++;
ifaddrmsg->ifa_family = AF_INET6;
ifaddrmsg->ifa_prefixlen = 128;
- if ((r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL, &in6addr_loopback, sizeof(in6addr_loopback))) < 0)
+ r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL,
+ &in6addr_loopback, sizeof(in6addr_loopback));
+ if (r < 0)
return r;
if (sendto_loop(fd, &request, request.header.nlmsg_len, 0, &sa.sa, sizeof(sa)) < 0)
union {
struct sockaddr sa;
struct sockaddr_nl nl;
- } sa;
+ } sa = {
+ .nl.nl_family = AF_NETLINK,
+ };
+
union {
struct nlmsghdr header;
uint8_t buf[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
NLMSG_ALIGN(sizeof(struct ifinfomsg))];
- } request;
+ } request = {
+ .header.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+ .header.nlmsg_type = RTM_NEWLINK,
+ .header.nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK,
+ .header.nlmsg_seq = *requests + 1,
+ };
struct ifinfomsg *ifinfomsg;
- zero(request);
-
- request.header.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
- request.header.nlmsg_type = RTM_NEWLINK;
- request.header.nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK;
- request.header.nlmsg_seq = *requests + 1;
-
ifinfomsg = NLMSG_DATA(&request.header);
ifinfomsg->ifi_family = AF_UNSPEC;
ifinfomsg->ifi_index = if_loopback;
ifinfomsg->ifi_flags = IFF_UP;
ifinfomsg->ifi_change = IFF_UP;
- zero(sa);
- sa.nl.nl_family = AF_NETLINK;
-
if (sendto_loop(fd, &request, request.header.nlmsg_len, 0, &sa.sa, sizeof(sa)) < 0)
return -errno;
socklen_t sa_len = sizeof(sa);
struct nlmsgerr *nlmsgerr;
- if ((l = recvfrom_loop(fd, &response, sizeof(response), 0, &sa.sa, &sa_len)) < 0)
+ l = recvfrom_loop(fd, &response, sizeof(response), 0, &sa.sa, &sa_len);
+ if (l < 0)
return -errno;
if (sa_len != sizeof(sa.nl) ||
nlmsgerr = NLMSG_DATA(&response.header);
- if (nlmsgerr->error < 0 && nlmsgerr->error != -EEXIST) {
- log_warning("Netlink failure for request %i: %s", response.header.nlmsg_seq, strerror(-nlmsgerr->error));
+ if (nlmsgerr->error < 0 && nlmsgerr->error != -EEXIST)
return nlmsgerr->error;
- }
return response.header.nlmsg_seq;
}
+static int check_loopback(void) {
+ int r;
+ _cleanup_close_ int fd;
+ union {
+ struct sockaddr sa;
+ struct sockaddr_in in;
+ } sa = {
+ .in.sin_family = AF_INET,
+ .in.sin_addr.s_addr = INADDR_LOOPBACK,
+ };
+
+ /* If we failed to set up the loop back device, check whether
+ * it might already be set up */
+
+ fd = socket(AF_INET, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0);
+ if (fd < 0)
+ return -errno;
+
+ if (bind(fd, &sa.sa, sizeof(sa.in)) >= 0)
+ r = 1;
+ else
+ r = errno == EADDRNOTAVAIL ? 0 : -errno;
+
+ return r;
+}
+
int loopback_setup(void) {
int r, if_loopback;
union {
struct sockaddr sa;
struct sockaddr_nl nl;
- struct sockaddr_storage storage;
- } sa;
+ } sa = {
+ .nl.nl_family = AF_NETLINK,
+ };
unsigned requests = 0, i;
- int fd;
+ _cleanup_close_ int fd = -1;
+ bool eperm = false;
errno = 0;
- if ((if_loopback = (int) if_nametoindex("lo")) <= 0)
+ if_loopback = (int) if_nametoindex("lo");
+ if (if_loopback <= 0)
return errno ? -errno : -ENODEV;
- if ((fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) < 0)
+ fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (fd < 0)
return -errno;
- zero(sa);
- sa.nl.nl_family = AF_NETLINK;
-
if (bind(fd, &sa.sa, sizeof(sa)) < 0) {
r = -errno;
- goto finish;
+ goto error;
}
- if ((r = add_adresses(fd, if_loopback, &requests)) < 0)
- goto finish;
+ r = add_adresses(fd, if_loopback, &requests);
+ if (r < 0)
+ goto error;
- if ((r = start_interface(fd, if_loopback, &requests)) < 0)
- goto finish;
+ r = start_interface(fd, if_loopback, &requests);
+ if (r < 0)
+ goto error;
for (i = 0; i < requests; i++) {
- if ((r = read_response(fd, requests)) < 0)
- goto finish;
- }
+ r = read_response(fd, requests);
- r = 0;
+ if (r == -EPERM)
+ eperm = true;
+ else if (r < 0)
+ goto error;
+ }
-finish:
- if (r < 0)
- log_warning("Failed to configure loopback device: %s", strerror(-r));
+ if (eperm && check_loopback() < 0) {
+ r = -EPERM;
+ goto error;
+ }
- if (fd >= 0)
- close_nointr_nofail(fd);
+ return 0;
+error:
+ log_warning("Failed to configure loopback device: %s", strerror(-r));
return r;
}