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Change the readrawsocket API a little so that we know when EOF is reached.

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This allows us to remove the non blocking option from our sockets due to the way BPF works.
This commit is contained in:
Roy Marples 2014-05-02 23:54:29 +00:00
parent 94cb985a8e
commit 68e672702b
9 changed files with 204 additions and 221 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arp.c
View File

@ -134,14 +134,20 @@ arp_packet(void *arg)
const char *hwaddr;
struct in_addr ina;
char hwbuf[HWADDR_LEN * 3];
int flags;
state = D_STATE(ifp);
state->fail.s_addr = 0;
for(;;) {
flags = 0;
while (!(flags & RAW_EOF)) {
bytes = if_readrawpacket(ifp, ETHERTYPE_ARP,
arp_buffer, sizeof(arp_buffer), NULL);
if (bytes == 0 || bytes == -1)
arp_buffer, sizeof(arp_buffer), &flags);
if (bytes == 0 || bytes == -1) {
syslog(LOG_ERR, "%s: arp if_readrawpacket: %m",
ifp->name);
dhcp_close(ifp);
return;
}
/* We must have a full ARP header */
if ((size_t)bytes < sizeof(ar))
continue;

55
dhcp.c
View File

@ -2557,55 +2557,58 @@ valid_udp_packet(const uint8_t *data, size_t data_len, struct in_addr *from,
static void
dhcp_handlepacket(void *arg)
{
struct interface *iface = arg;
struct interface *ifp = arg;
struct dhcp_message *dhcp = NULL;
const uint8_t *pp;
size_t bytes;
struct in_addr from;
int i, partialcsum = 0;
const struct dhcp_state *state = D_CSTATE(iface);
int i, flags;
const struct dhcp_state *state = D_CSTATE(ifp);
/* We loop through until our buffer is empty.
* The benefit is that if we get >1 DHCP packet in our buffer and
* the first one fails for any reason, we can use the next. */
for(;;) {
bytes = (size_t)if_readrawpacket(iface, ETHERTYPE_IP,
iface->ctx->packet, udp_dhcp_len, &partialcsum);
if (bytes == 0 || (ssize_t)bytes == -1)
/* Need this API due to BPF */
flags = 0;
while (!(flags & RAW_EOF)) {
bytes = (size_t)if_readrawpacket(ifp, ETHERTYPE_IP,
ifp->ctx->packet, udp_dhcp_len, &flags);
if (bytes == 0 || (ssize_t)bytes == -1) {
syslog(LOG_ERR, "%s: dhcp if_readrawpacket: %m",
ifp->name);
dhcp_close(ifp);
break;
if (valid_udp_packet(iface->ctx->packet, bytes,
&from, partialcsum) == -1)
}
if (valid_udp_packet(ifp->ctx->packet, bytes,
&from, flags & RAW_PARTIALCSUM) == -1)
{
syslog(LOG_ERR, "%s: invalid UDP packet from %s",
iface->name, inet_ntoa(from));
ifp->name, inet_ntoa(from));
continue;
}
i = whitelisted_ip(iface->options, from.s_addr);
i = whitelisted_ip(ifp->options, from.s_addr);
if (i == 0) {
syslog(LOG_WARNING,
"%s: non whitelisted DHCP packet from %s",
iface->name, inet_ntoa(from));
ifp->name, inet_ntoa(from));
continue;
} else if (i != 1 &&
blacklisted_ip(iface->options, from.s_addr) == 1)
blacklisted_ip(ifp->options, from.s_addr) == 1)
{
syslog(LOG_WARNING,
"%s: blacklisted DHCP packet from %s",
iface->name, inet_ntoa(from));
ifp->name, inet_ntoa(from));
continue;
}
if (iface->flags & IFF_POINTOPOINT &&
if (ifp->flags & IFF_POINTOPOINT &&
state->dst.s_addr != from.s_addr)
{
syslog(LOG_WARNING,
"%s: server %s is not destination",
iface->name, inet_ntoa(from));
ifp->name, inet_ntoa(from));
}
bytes = get_udp_data(&pp, iface->ctx->packet);
bytes = get_udp_data(&pp, ifp->ctx->packet);
if (bytes > sizeof(*dhcp)) {
syslog(LOG_ERR,
"%s: packet greater than DHCP size from %s",
iface->name, inet_ntoa(from));
ifp->name, inet_ntoa(from));
continue;
}
if (dhcp == NULL) {
@ -2618,22 +2621,22 @@ dhcp_handlepacket(void *arg)
memcpy(dhcp, pp, bytes);
if (dhcp->cookie != htonl(MAGIC_COOKIE)) {
syslog(LOG_DEBUG, "%s: bogus cookie from %s",
iface->name, inet_ntoa(from));
ifp->name, inet_ntoa(from));
continue;
}
/* Ensure packet is for us */
if (iface->hwlen <= sizeof(dhcp->chaddr) &&
memcmp(dhcp->chaddr, iface->hwaddr, iface->hwlen))
if (ifp->hwlen <= sizeof(dhcp->chaddr) &&
memcmp(dhcp->chaddr, ifp->hwaddr, ifp->hwlen))
{
char buf[sizeof(dhcp->chaddr) * 3];
syslog(LOG_DEBUG, "%s: xid 0x%x is not for hwaddr %s",
iface->name, ntohl(dhcp->xid),
ifp->name, ntohl(dhcp->xid),
hwaddr_ntoa(dhcp->chaddr, sizeof(dhcp->chaddr),
buf, sizeof(buf)));
continue;
}
dhcp_handledhcp(iface, &dhcp, &from);
dhcp_handledhcp(ifp, &dhcp, &from);
if (state->raw_fd == -1)
break;
}

5
dhcp6.c
View File

@ -2036,8 +2036,11 @@ dhcp6_handledata(void *arg)
ctx = dhcpcd_ctx->ipv6;
ctx->rcvhdr.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo));
bytes = recvmsg(ctx->dhcp_fd, &ctx->rcvhdr, 0);
if (bytes == -1) {
if (bytes == -1 || bytes == 0) {
syslog(LOG_ERR, "recvmsg: %m");
close(ctx->dhcp_fd);
eloop_event_delete(dhcpcd_ctx->eloop, ctx->dhcp_fd);
ctx->dhcp_fd = -1;
return;
}
len = (size_t)bytes;

6
dhcpcd.c
View File

@ -641,8 +641,12 @@ handle_link(void *arg)
struct dhcpcd_ctx *ctx;
ctx = arg;
if (if_managelink(ctx) == -1 && errno != ENXIO && errno != ENODEV)
if (if_managelink(ctx) == -1) {
syslog(LOG_ERR, "if_managelink: %m");
eloop_event_delete(ctx->eloop, ctx->link_fd);
close(ctx->link_fd);
ctx->link_fd = -1;
}
}
static void

4
eloop.c
View File

@ -386,7 +386,7 @@ eloop_start(struct dhcpcd_ctx *dctx)
n = poll(ctx->fds, ctx->events_len, timeout);
#endif
if (n == -1) {
if (errno == EAGAIN || errno == EINTR)
if (errno == EINTR)
continue;
syslog(LOG_ERR, "poll: %m");
break;
@ -395,7 +395,7 @@ eloop_start(struct dhcpcd_ctx *dctx)
/* Process any triggered events. */
if (n > 0) {
TAILQ_FOREACH(e, &ctx->events, next) {
if (e->pollfd->revents & (POLLIN | POLLHUP)) {
if (e->pollfd->revents & (POLLIN)) {
e->callback(e->arg);
/* We need to break here as the
* callback could destroy the next

292
if-bsd.c
View File

@ -114,7 +114,7 @@ if_openlinksocket(void)
{
#ifdef SOCK_CLOEXEC
return socket(PF_ROUTE, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, 0);
return socket(PF_ROUTE, SOCK_RAW | SOCK_CLOEXEC, 0);
#else
int s, flags;
@ -126,12 +126,6 @@ if_openlinksocket(void)
close(s);
return -1;
}
if ((flags = fcntl(s, F_GETFL, 0)) == -1 ||
fcntl(s, F_SETFL, flags | O_NONBLOCK) == -1)
{
close(s);
return -1;
}
return s;
#endif
}
@ -228,14 +222,14 @@ if_openrawsocket(struct interface *ifp, int protocol)
int flags;
#endif
#ifdef _PATH_BPF
fd = open(_PATH_BPF, O_RDWR | O_CLOEXEC | O_NONBLOCK);
fd = open(_PATH_BPF, O_RDWR | O_CLOEXEC);
#else
char device[32];
int n = 0;
do {
snprintf(device, sizeof(device), "/dev/bpf%d", n++);
fd = open(device, O_RDWR | O_CLOEXEC | O_NONBLOCK);
fd = open(device, O_RDWR | O_CLOEXEC);
} while (fd == -1 && errno == EBUSY);
#endif
@ -289,13 +283,6 @@ if_openrawsocket(struct interface *ifp, int protocol)
if (ioctl(fd, BIOCSETF, &pf) == -1)
goto eexit;
#ifdef __OpenBSD__
/* For some reason OpenBSD fails to open the fd as non blocking */
if ((flags = fcntl(fd, F_GETFL, 0)) == -1 ||
fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1)
goto eexit;
#endif
return fd;
eexit:
@ -333,9 +320,9 @@ if_sendrawpacket(const struct interface *ifp, int protocol,
* So we pass the buffer in the API so we can loop on >1 packet. */
ssize_t
if_readrawpacket(struct interface *ifp, int protocol,
void *data, size_t len, int *partialcsum)
void *data, size_t len, int *flags)
{
int fd = -1;
int fd;
struct bpf_hdr packet;
ssize_t bytes;
const unsigned char *payload;
@ -347,16 +334,14 @@ if_readrawpacket(struct interface *ifp, int protocol,
else
fd = state->raw_fd;
if (partialcsum != NULL)
*partialcsum = 0; /* Not supported on BSD */
if (flags != NULL)
*flags = 0; /* Not supported on BSD */
for (;;) {
if (state->buffer_len == 0) {
bytes = read(fd, state->buffer, state->buffer_size);
if (bytes == -1)
return errno == EAGAIN ? 0 : -1;
else if ((size_t)bytes < sizeof(packet))
return -1;
if (bytes == -1 || bytes == 0)
return bytes;
state->buffer_len = (size_t)bytes;
state->buffer_pos = 0;
}
@ -377,8 +362,10 @@ if_readrawpacket(struct interface *ifp, int protocol,
next:
state->buffer_pos += BPF_WORDALIGN(packet.bh_hdrlen +
packet.bh_caplen);
if (state->buffer_pos >= state->buffer_len)
if (state->buffer_pos >= state->buffer_len) {
state->buffer_len = state->buffer_pos = 0;
*flags |= RAW_EOF;
}
if (bytes != -1)
return bytes;
}
@ -774,143 +761,136 @@ if_managelink(struct dhcpcd_ctx *ctx)
int ifa_flags;
#endif
for (;;) {
bytes = read(ctx->link_fd, msg, sizeof(msg));
if (bytes == -1) {
if (errno == EAGAIN)
return 0;
if (errno == EINTR)
continue;
return -1;
}
e = msg + bytes;
for (p = msg; p < e; p += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)p;
// Ignore messages generated by us
if (rtm->rtm_pid == getpid())
break;
switch(rtm->rtm_type) {
bytes = read(ctx->link_fd, msg, sizeof(msg));
if (bytes == -1 || bytes == 0)
return bytes;
e = msg + bytes;
for (p = msg; p < e; p += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)p;
// Ignore messages generated by us
if (rtm->rtm_pid == getpid())
break;
switch(rtm->rtm_type) {
#ifdef RTM_IFANNOUNCE
case RTM_IFANNOUNCE:
ifan = (struct if_announcemsghdr *)(void *)p;
switch(ifan->ifan_what) {
case IFAN_ARRIVAL:
dhcpcd_handleinterface(ctx, 1,
ifan->ifan_name);
break;
case IFAN_DEPARTURE:
dhcpcd_handleinterface(ctx, -1,
ifan->ifan_name);
break;
}
case RTM_IFANNOUNCE:
ifan = (struct if_announcemsghdr *)(void *)p;
switch(ifan->ifan_what) {
case IFAN_ARRIVAL:
dhcpcd_handleinterface(ctx, 1,
ifan->ifan_name);
break;
#endif
case RTM_IFINFO:
ifm = (struct if_msghdr *)(void *)p;
memset(ifname, 0, sizeof(ifname));
if (!(if_indextoname(ifm->ifm_index, ifname)))
break;
switch (ifm->ifm_data.ifi_link_state) {
case LINK_STATE_DOWN:
len = LINK_DOWN;
break;
case LINK_STATE_UP:
len = LINK_UP;
break;
default:
/* handle_carrier will re-load
* the interface flags and check for
* IFF_RUNNING as some drivers that
* don't handle link state also don't
* set IFF_RUNNING when this routing
* message is generated.
* As such, it is a race ...*/
len = LINK_UNKNOWN;
break;
}
dhcpcd_handlecarrier(ctx, len,
(unsigned int)ifm->ifm_flags, ifname);
break;
case RTM_DELETE:
if (~rtm->rtm_addrs &
(RTA_DST | RTA_GATEWAY | RTA_NETMASK))
break;
cp = (char *)(void *)(rtm + 1);
sa = (struct sockaddr *)(void *)cp;
if (sa->sa_family != AF_INET)
break;
#ifdef INET
get_addrs(rtm->rtm_addrs, cp, rti_info);
memset(&rt, 0, sizeof(rt));
rt.iface = NULL;
COPYOUT(rt.dest, rti_info[RTAX_DST]);
COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
COPYOUT(rt.gate, rti_info[RTAX_GATEWAY]);
ipv4_routedeleted(ctx, &rt);
#endif
break;
#ifdef RTM_CHGADDR
case RTM_CHGADDR: /* FALLTHROUGH */
#endif
case RTM_DELADDR: /* FALLTHROUGH */
case RTM_NEWADDR:
ifam = (struct ifa_msghdr *)(void *)p;
if (!if_indextoname(ifam->ifam_index, ifname))
break;
cp = (char *)(void *)(ifam + 1);
get_addrs(ifam->ifam_addrs, cp, rti_info);
if (rti_info[RTAX_IFA] == NULL)
break;
switch (rti_info[RTAX_IFA]->sa_family) {
case AF_LINK:
#ifdef RTM_CHGADDR
if (rtm->rtm_type != RTM_CHGADDR)
break;
#else
if (rtm->rtm_type != RTM_NEWADDR)
break;
#endif
memcpy(&sdl, rti_info[RTAX_IFA],
rti_info[RTAX_IFA]->sa_len);
dhcpcd_handlehwaddr(ctx, ifname,
(const unsigned char*)CLLADDR(&sdl),
sdl.sdl_alen);
break;
#ifdef INET
case AF_INET:
case 255: /* FIXME: Why 255? */
COPYOUT(rt.dest, rti_info[RTAX_IFA]);
COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
COPYOUT(rt.gate, rti_info[RTAX_BRD]);
ipv4_handleifa(ctx, rtm->rtm_type,
NULL, ifname,
&rt.dest, &rt.net, &rt.gate);
break;
#endif
#ifdef INET6
case AF_INET6:
sin6 = (struct sockaddr_in6*)(void *)
rti_info[RTAX_IFA];
memcpy(ia6.s6_addr,
sin6->sin6_addr.s6_addr,
sizeof(ia6.s6_addr));
if (rtm->rtm_type == RTM_NEWADDR) {
ifa_flags = if_addrflags6(
ifname,
&ia6);
if (ifa_flags == -1)
break;
} else
ifa_flags = 0;
ipv6_handleifa(ctx, rtm->rtm_type, NULL,
ifname, &ia6, ifa_flags);
break;
#endif
}
case IFAN_DEPARTURE:
dhcpcd_handleinterface(ctx, -1,
ifan->ifan_name);
break;
}
break;
#endif
case RTM_IFINFO:
ifm = (struct if_msghdr *)(void *)p;
memset(ifname, 0, sizeof(ifname));
if (!(if_indextoname(ifm->ifm_index, ifname)))
break;
switch (ifm->ifm_data.ifi_link_state) {
case LINK_STATE_DOWN:
len = LINK_DOWN;
break;
case LINK_STATE_UP:
len = LINK_UP;
break;
default:
/* handle_carrier will re-load
* the interface flags and check for
* IFF_RUNNING as some drivers that
* don't handle link state also don't
* set IFF_RUNNING when this routing
* message is generated.
* As such, it is a race ...*/
len = LINK_UNKNOWN;
break;
}
dhcpcd_handlecarrier(ctx, len,
(unsigned int)ifm->ifm_flags, ifname);
break;
case RTM_DELETE:
if (~rtm->rtm_addrs &
(RTA_DST | RTA_GATEWAY | RTA_NETMASK))
break;
cp = (char *)(void *)(rtm + 1);
sa = (struct sockaddr *)(void *)cp;
if (sa->sa_family != AF_INET)
break;
#ifdef INET
get_addrs(rtm->rtm_addrs, cp, rti_info);
memset(&rt, 0, sizeof(rt));
rt.iface = NULL;
COPYOUT(rt.dest, rti_info[RTAX_DST]);
COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
COPYOUT(rt.gate, rti_info[RTAX_GATEWAY]);
ipv4_routedeleted(ctx, &rt);
#endif
break;
#ifdef RTM_CHGADDR
case RTM_CHGADDR: /* FALLTHROUGH */
#endif
case RTM_DELADDR: /* FALLTHROUGH */
case RTM_NEWADDR:
ifam = (struct ifa_msghdr *)(void *)p;
if (!if_indextoname(ifam->ifam_index, ifname))
break;
cp = (char *)(void *)(ifam + 1);
get_addrs(ifam->ifam_addrs, cp, rti_info);
if (rti_info[RTAX_IFA] == NULL)
break;
switch (rti_info[RTAX_IFA]->sa_family) {
case AF_LINK:
#ifdef RTM_CHGADDR
if (rtm->rtm_type != RTM_CHGADDR)
break;
#else
if (rtm->rtm_type != RTM_NEWADDR)
break;
#endif
memcpy(&sdl, rti_info[RTAX_IFA],
rti_info[RTAX_IFA]->sa_len);
dhcpcd_handlehwaddr(ctx, ifname,
(const unsigned char*)CLLADDR(&sdl),
sdl.sdl_alen);
break;
#ifdef INET
case AF_INET:
case 255: /* FIXME: Why 255? */
COPYOUT(rt.dest, rti_info[RTAX_IFA]);
COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
COPYOUT(rt.gate, rti_info[RTAX_BRD]);
ipv4_handleifa(ctx, rtm->rtm_type,
NULL, ifname,
&rt.dest, &rt.net, &rt.gate);
break;
#endif
#ifdef INET6
case AF_INET6:
sin6 = (struct sockaddr_in6*)(void *)
rti_info[RTAX_IFA];
memcpy(ia6.s6_addr,
sin6->sin6_addr.s6_addr,
sizeof(ia6.s6_addr));
if (rtm->rtm_type == RTM_NEWADDR) {
ifa_flags = if_addrflags6(ifname, &ia6);
if (ifa_flags == -1)
break;
} else
ifa_flags = 0;
ipv6_handleifa(ctx, rtm->rtm_type, NULL,
ifname, &ia6, ifa_flags);
break;
#endif
}
break;
}
}
return 0;
}
#ifndef SYS_NMLN /* OSX */

39
if-linux.c
View File

@ -272,15 +272,9 @@ get_netlink(struct dhcpcd_ctx *ctx, int fd, int flags,
for (;;) {
bytes = recv(fd, NULL, 0,
flags | MSG_PEEK | MSG_DONTWAIT | MSG_TRUNC);
if (bytes == -1) {
if (errno == EAGAIN) {
r = 0;
goto eexit;
}
if (errno == EINTR)
continue;
if (bytes == -1 || bytes == 0)
goto eexit;
} else if ((size_t)bytes == buflen) {
if ((size_t)bytes == buflen) {
/* Support kernels older than 2.6.22 */
if (bytes == 0)
bytes = 512;
@ -297,15 +291,8 @@ get_netlink(struct dhcpcd_ctx *ctx, int fd, int flags,
}
bytes = recvfrom(fd, buf, buflen, flags,
(struct sockaddr *)&nladdr, &nladdr_len);
if (bytes == -1) {
if (errno == EAGAIN) {
r = 0;
goto eexit;
}
if (errno == EINTR)
continue;
if (bytes == -1 || bytes == 0)
goto eexit;
}
/* Check sender */
if (nladdr_len != sizeof(nladdr)) {
@ -752,7 +739,7 @@ if_openrawsocket(struct interface *ifp, int protocol)
#endif
#ifdef SOCK_CLOEXEC
if ((s = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
if ((s = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC,
htons(protocol))) == -1)
return -1;
#else
@ -766,12 +753,6 @@ if_openrawsocket(struct interface *ifp, int protocol)
close(s);
return -1;
}
if ((flags = fcntl(s, F_GETFL, 0)) == -1 ||
fcntl(s, F_SETFL, flags | O_NONBLOCK) == -1)
{
close(s);
return -1;
}
#endif
/* Install the DHCP filter */
memset(&pf, 0, sizeof(pf));
@ -839,7 +820,7 @@ if_sendrawpacket(const struct interface *ifp, int protocol,
ssize_t
if_readrawpacket(struct interface *ifp, int protocol,
void *data, size_t len, int *partialcsum)
void *data, size_t len, int *flags)
{
struct iovec iov = {
.iov_base = data,
@ -871,9 +852,9 @@ if_readrawpacket(struct interface *ifp, int protocol,
fd = state->raw_fd;
bytes = recvmsg(fd, &msg, 0);
if (bytes == -1)
return errno == EAGAIN ? 0 : -1;
if (partialcsum != NULL) {
*partialcsum = 0;
return -1;
if (bytes) {
*flags &= ~RAW_PARTIALCSUM;
#ifdef PACKET_AUXDATA
for (cmsg = CMSG_FIRSTHDR(&msg);
cmsg;
@ -882,8 +863,8 @@ if_readrawpacket(struct interface *ifp, int protocol,
if (cmsg->cmsg_level == SOL_PACKET &&
cmsg->cmsg_type == PACKET_AUXDATA) {
aux = (void *)CMSG_DATA(cmsg);
*partialcsum = aux->tp_status &
TP_STATUS_CSUMNOTREADY;
if (aux->tp_status & TP_STATUS_CSUMNOTREADY)
*flags |= RAW_PARTIALCSUM;
}
}
#endif

3
if.h
View File

@ -80,6 +80,9 @@
# define IN_LINKLOCAL(addr) ((addr & IN_CLASSB_NET) == LINKLOCAL_ADDR)
#endif
#define RAW_EOF 1 << 0
#define RAW_PARTIALCSUM 2 << 0
struct if_head *if_discover(struct dhcpcd_ctx *, int, char * const *);
struct interface *if_find(struct dhcpcd_ctx *, const char *);
void if_free(struct interface *);

9
ipv6nd.c
View File

@ -1166,10 +1166,10 @@ ipv6nd_proberouter(void *arg)
pi.ipi6_ifindex = rap->iface->index;
memcpy(CMSG_DATA(cm), &pi, sizeof(pi));
#ifdef DEBUG_NS
//#ifdef DEBUG_NS
syslog(LOG_INFO, "%s: sending IPv6 NS for %s",
rap->iface->name, rap->sfrom);
#endif
//#endif
if (sendmsg(ctx->nd_fd, &ctx->sndhdr, 0) == -1) {
syslog(LOG_ERR, "%s: %s: sendmsg: %m",
rap->iface->name, __func__);
@ -1432,8 +1432,11 @@ ipv6nd_handledata(void *arg)
ctx->rcvhdr.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
CMSG_SPACE(sizeof(int));
len = recvmsg(ctx->nd_fd, &ctx->rcvhdr, 0);
if (len == -1) {
if (len == -1 || len == 0) {
syslog(LOG_ERR, "recvmsg: %m");
eloop_event_delete(dhcpcd_ctx->eloop, ctx->nd_fd);
close(ctx->nd_fd);
ctx->nd_fd = -1;
return;
}
ctx->sfrom = inet_ntop(AF_INET6, &ctx->from.sin6_addr,