void netlink_multicast(void)
{
ssize_t len;
struct nlmsghdr *h;
int flags, newaddr = 0;
/* don't risk blocking reading netlink messages here. */
if ((flags = fcntl(daemon->netlinkfd, F_GETFL)) == -1 ||
fcntl(daemon->netlinkfd, F_SETFL, flags | O_NONBLOCK) == -1)
return;
if ((len = netlink_recv()) != -1)
for (h = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(h, (size_t)len); h = NLMSG_NEXT(h, len))
if (nl_async(h) && option_bool(OPT_CLEVERBIND))
newaddr = 1;
/* restore non-blocking status */
fcntl(daemon->netlinkfd, F_SETFL, flags);
if (newaddr)
{
enumerate_interfaces();
create_bound_listeners(0);
}
}
static void nl_newaddress(time_t now)
{
if (option_bool(OPT_CLEVERBIND) || daemon->doing_dhcp6 || daemon->doing_ra)
enumerate_interfaces();
if (option_bool(OPT_CLEVERBIND))
create_bound_listeners(0);
#ifdef HAVE_DHCP6
if (daemon->doing_dhcp6 || daemon->doing_ra)
{
join_multicast(0);
dhcp_construct_contexts(now);
}
if (daemon->doing_dhcp6)
lease_find_interfaces(now);
#endif
}
int main (int argc, char **argv)
{
char *int_err_string;
int cachesize = CACHESIZ;
int port = NAMESERVER_PORT;
int query_port = 0;
unsigned long local_ttl = 0;
int logged_lease = 0, first_loop = 1;
unsigned int options;
char *runfile = RUNFILE;
time_t resolv_changed = 0;
time_t now, last = 0;
time_t lease_file_change = 0;
ino_t lease_file_inode = (ino_t)0;
struct irec *iface, *interfaces = NULL;
char *mxname = NULL;
char *mxtarget = NULL;
char *lease_file = NULL;
char *addn_hosts = NULL;
char *domain_suffix = NULL;
char *username = CHUSER;
char *groupname = CHGRP;
struct iname *if_names = NULL;
struct iname *if_addrs = NULL;
struct iname *if_except = NULL;
struct iname *if_tmp;
struct server *serv_addrs = NULL;
char *dnamebuff, *packet;
struct server *servers, *last_server;
struct resolvc default_resolv = { NULL, 1, 0, RESOLVFILE };
struct resolvc *resolv = &default_resolv;
struct bogus_addr *bogus_addr = NULL;
struct serverfd *serverfdp, *sfds = NULL;
sighup = 1; /* init cache the first time through */
sigusr1 = 0; /* but don't dump */
sigusr2 = 0; /* or rescan interfaces */
signal(SIGUSR1, sig_handler);
signal(SIGUSR2, sig_handler);
signal(SIGHUP, sig_handler);
/* These get allocated here to avoid overflowing the small stack
on embedded systems. dnamebuff is big enough to hold one
maximal sixed domain name and gets passed into all the processing
code. We manage to get away with one buffer. */
dnamebuff = safe_malloc(MAXDNAME);
/* Size: we check after adding each record, so there must be
memory for the largest packet, and the largest record */
packet = safe_malloc(PACKETSZ+MAXDNAME+RRFIXEDSZ);
options = read_opts(argc, argv, dnamebuff, &resolv, &mxname, &mxtarget, &lease_file,
&username, &groupname, &domain_suffix, &runfile,
&if_names, &if_addrs, &if_except, &bogus_addr,
&serv_addrs, &cachesize, &port, &query_port, &local_ttl, &addn_hosts);
int_err_string = enumerate_interfaces(&interfaces, if_names, if_addrs, if_except, port);
if (int_err_string)
die(int_err_string, NULL);
for (if_tmp = if_names; if_tmp; if_tmp = if_tmp->next)
if (if_tmp->name && !if_tmp->found)
die("unknown interface %s", if_tmp->name);
for (if_tmp = if_addrs; if_tmp; if_tmp = if_tmp->next)
if (!if_tmp->found)
{
char addrbuff[ADDRSTRLEN];
#ifdef HAVE_IPV6
if (if_tmp->addr.sa.sa_family == AF_INET)
inet_ntop(AF_INET, &if_tmp->addr.in.sin_addr,
addrbuff, ADDRSTRLEN);
else
inet_ntop(AF_INET6, &if_tmp->addr.in6.sin6_addr,
addrbuff, ADDRSTRLEN);
#else
strcpy(addrbuff, inet_ntoa(if_tmp->addr.in.sin_addr));
#endif
die("no interface with address %s", addrbuff);
}
forward_init(1);
cache_init(cachesize, options & OPT_LOG);
setbuf(stdout, NULL);
if (!(options & OPT_DEBUG))
{
FILE *pidfile;
struct passwd *ent_pw;
int i;
/* The following code "daemonizes" the process.
See Stevens section 12.4 */
#ifndef NO_FORK
if (fork() != 0 )
exit(0);
setsid();
if (fork() != 0)
exit(0);
#endif
chdir("/");
umask(022); /* make pidfile 0644 */
/* write pidfile _after_ forking ! */
if (runfile && (pidfile = fopen(runfile, "w")))
{
fprintf(pidfile, "%d\n", (int) getpid());
fclose(pidfile);
}
umask(0);
for (i=0; i<64; i++)
{
for (iface = interfaces; iface; iface = iface->next)
if (iface->fd == i)
break;
if (iface)
continue;
close(i);
}
/* Change uid and gid for security */
if (username && (ent_pw = getpwnam(username)))
{
gid_t dummy;
struct group *gp;
/* remove all supplimentary groups */
setgroups(0, &dummy);
/* change group for /etc/ppp/resolv.conf
otherwise get the group for "nobody" */
if ((groupname && (gp = getgrnam(groupname))) ||
(gp = getgrgid(ent_pw->pw_gid)))
setgid(gp->gr_gid);
/* finally drop root */
setuid(ent_pw->pw_uid);
}
}
openlog("dnsmasq",
DNSMASQ_LOG_OPT(options & OPT_DEBUG),
DNSMASQ_LOG_FAC(options & OPT_DEBUG));
if (cachesize)
syslog(LOG_INFO, "started, version %s cachesize %d", VERSION, cachesize);
else
syslog(LOG_INFO, "started, version %s cache disabled", VERSION);
if (options & OPT_LOCALMX)
syslog(LOG_INFO, "serving MX record for local hosts target %s", mxtarget);
else if (mxname)
syslog(LOG_INFO, "serving MX record for mailhost %s target %s",
mxname, mxtarget);
if (getuid() == 0 || geteuid() == 0)
syslog(LOG_WARNING, "failed to drop root privs");
servers = last_server = check_servers(serv_addrs, interfaces, &sfds);
while (1)
{
int ready, maxfd = 0;
fd_set rset;
HEADER *header;
struct stat statbuf;
if (first_loop)
/* do init stuff only first time round. */
{
first_loop = 0;
ready = 0;
}
else
{
FD_ZERO(&rset);
for (serverfdp = sfds; serverfdp; serverfdp = serverfdp->next)
{
FD_SET(serverfdp->fd, &rset);
if (serverfdp->fd > maxfd)
maxfd = serverfdp->fd;
}
for (iface = interfaces; iface; iface = iface->next)
{
FD_SET(iface->fd, &rset);
if (iface->fd > maxfd)
maxfd = iface->fd;
}
ready = select(maxfd+1, &rset, NULL, NULL, NULL);
if (ready == -1)
{
if (errno == EINTR)
ready = 0; /* do signal handlers */
else
continue;
}
}
if (sighup)
{
signal(SIGHUP, SIG_IGN);
cache_reload(options, dnamebuff, domain_suffix, addn_hosts);
if (resolv && (options & OPT_NO_POLL))
servers = last_server =
check_servers(reload_servers(resolv->name, dnamebuff, servers, query_port),
interfaces, &sfds);
sighup = 0;
signal(SIGHUP, sig_handler);
}
if (sigusr1)
{
signal(SIGUSR1, SIG_IGN);
dump_cache(options & (OPT_DEBUG | OPT_LOG), cachesize);
sigusr1 = 0;
signal(SIGUSR1, sig_handler);
}
if (sigusr2)
{
signal(SIGUSR2, SIG_IGN);
if (getuid() != 0 && port <= 1024)
syslog(LOG_ERR, "cannot re-scan interfaces unless --user=root");
else
{
syslog(LOG_INFO, "rescanning network interfaces");
int_err_string = enumerate_interfaces(&interfaces, if_names, if_addrs, if_except, port);
if (int_err_string)
syslog(LOG_ERR, int_err_string, strerror(errno));
}
sigusr2 = 0;
signal(SIGUSR2, sig_handler);
/* may be new file descriptors now, so redo select() */
ready = 0;
}
now = time(NULL);
/* Check for changes to resolv files and DHCP leases file once per second max. */
if (last == 0 || now > last)
{
last = now;
if (!(options & OPT_NO_POLL))
{
struct resolvc *res = resolv, *latest = NULL;
time_t last_change = 0;
/* There may be more than one possible file.
Go through and find the one which changed _last_.
Warn of any which can't be read. */
while (res)
{
if (stat(res->name, &statbuf) == -1)
{
if (!res->logged)
syslog(LOG_WARNING, "failed to access %s: %m", res->name);
res->logged = 1;
}
else
{
res->logged = 0;
if (statbuf.st_mtime > last_change)
{
last_change = statbuf.st_mtime;
latest = res;
}
}
res = res->next;
}
if (latest && last_change > resolv_changed)
{
resolv_changed = last_change;
servers = last_server =
check_servers(reload_servers(latest->name, dnamebuff, servers, query_port),
interfaces, &sfds);
}
}
if (lease_file)
{
syslog(LOG_WARNING, "checking lease file %s", lease_file);
if (stat(lease_file, &statbuf) == -1)
{
if (!logged_lease)
syslog(LOG_WARNING, "failed to access %s: %m", lease_file);
logged_lease = 1;
}
else
{
logged_lease = 0;
if ((statbuf.st_mtime != lease_file_change) ||
(statbuf.st_ino != lease_file_inode))
{
lease_file_change = statbuf.st_mtime;
lease_file_inode = statbuf.st_ino;
load_dhcp(lease_file, domain_suffix, now, dnamebuff);
}
}
}
}
if (ready == 0)
continue; /* no sockets ready */
for (serverfdp = sfds; serverfdp; serverfdp = serverfdp->next)
if (FD_ISSET(serverfdp->fd, &rset))
last_server = reply_query(serverfdp->fd, options, packet, now,
dnamebuff, last_server, bogus_addr);
for (iface = interfaces; iface; iface = iface->next)
{
if (FD_ISSET(iface->fd, &rset))
{
/* request packet, deal with query */
union mysockaddr udpaddr;
socklen_t udplen = sizeof(udpaddr);
int m, n = recvfrom(iface->fd, packet, PACKETSZ, 0, &udpaddr.sa, &udplen);
udpaddr.sa.sa_family = iface->addr.sa.sa_family;
#ifdef HAVE_IPV6
if (udpaddr.sa.sa_family == AF_INET6)
udpaddr.in6.sin6_flowinfo = htonl(0);
#endif
header = (HEADER *)packet;
if (n >= (int)sizeof(HEADER) && !header->qr)
{
if (extract_request(header, (unsigned int)n, dnamebuff))
{
if (udpaddr.sa.sa_family == AF_INET)
log_query(F_QUERY | F_IPV4 | F_FORWARD, dnamebuff,
(struct all_addr *)&udpaddr.in.sin_addr);
#ifdef HAVE_IPV6
else
log_query(F_QUERY | F_IPV6 | F_FORWARD, dnamebuff,
(struct all_addr *)&udpaddr.in6.sin6_addr);
#endif
}
m = answer_request (header, ((char *) header) + PACKETSZ, (unsigned int)n,
mxname, mxtarget, options, now, local_ttl, dnamebuff);
if (m >= 1)
{
/* answered from cache, send reply */
sendto(iface->fd, (char *)header, m, 0,
&udpaddr.sa, sa_len(&udpaddr));
}
else
{
/* cannot answer from cache, send on to real nameserver */
last_server = forward_query(iface->fd, &udpaddr, header, n,
options, dnamebuff, servers,
last_server, now, local_ttl);
}
}
}
}
}
return 0;
}
void tftp_request(struct listener *listen, time_t now)
{
ssize_t len;
char *packet = daemon->packet;
char *filename, *mode, *p, *end, *opt;
union mysockaddr addr, peer;
struct msghdr msg;
struct iovec iov;
struct ifreq ifr;
int is_err = 1, if_index = 0, mtu = 0;
struct iname *tmp;
struct tftp_transfer *transfer;
int port = daemon->start_tftp_port; /* may be zero to use ephemeral port */
#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
int mtuflag = IP_PMTUDISC_DONT;
#endif
char namebuff[IF_NAMESIZE];
char *name = NULL;
char *prefix = daemon->tftp_prefix;
struct tftp_prefix *pref;
union all_addr addra;
/* Can always get recvd interface for IPv6 */
int check_dest = !option_bool(OPT_NOWILD) || listen->family == AF_INET6;
union {
struct cmsghdr align; /* this ensures alignment */
char control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
#if defined(HAVE_LINUX_NETWORK)
char control[CMSG_SPACE(sizeof(struct in_pktinfo))];
#elif defined(HAVE_SOLARIS_NETWORK)
char control[CMSG_SPACE(sizeof(unsigned int))];
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
char control[CMSG_SPACE(sizeof(struct sockaddr_dl))];
#endif
} control_u;
msg.msg_controllen = sizeof(control_u);
msg.msg_control = control_u.control;
msg.msg_flags = 0;
msg.msg_name = &peer;
msg.msg_namelen = sizeof(peer);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
iov.iov_base = packet;
iov.iov_len = daemon->packet_buff_sz;
/* we overwrote the buffer... */
daemon->srv_save = NULL;
if ((len = recvmsg(listen->tftpfd, &msg, 0)) < 2)
return;
/* Can always get recvd interface for IPv6 */
if (!check_dest)
{
if (listen->iface)
{
addr = listen->iface->addr;
name = listen->iface->name;
mtu = listen->iface->mtu;
if (daemon->tftp_mtu != 0 && daemon->tftp_mtu < mtu)
mtu = daemon->tftp_mtu;
}
else
{
/* we're listening on an address that doesn't appear on an interface,
ask the kernel what the socket is bound to */
socklen_t tcp_len = sizeof(union mysockaddr);
if (getsockname(listen->tftpfd, (struct sockaddr *)&addr, &tcp_len) == -1)
return;
}
}
else
{
struct cmsghdr *cmptr;
if (msg.msg_controllen < sizeof(struct cmsghdr))
return;
addr.sa.sa_family = listen->family;
#if defined(HAVE_LINUX_NETWORK)
if (listen->family == AF_INET)
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
{
union {
unsigned char *c;
struct in_pktinfo *p;
} p;
p.c = CMSG_DATA(cmptr);
addr.in.sin_addr = p.p->ipi_spec_dst;
if_index = p.p->ipi_ifindex;
}
#elif defined(HAVE_SOLARIS_NETWORK)
if (listen->family == AF_INET)
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
{
union {
unsigned char *c;
struct in_addr *a;
unsigned int *i;
} p;
p.c = CMSG_DATA(cmptr);
if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
addr.in.sin_addr = *(p.a);
else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
if_index = *(p.i);
}
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
if (listen->family == AF_INET)
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
{
union {
unsigned char *c;
struct in_addr *a;
struct sockaddr_dl *s;
} p;
p.c = CMSG_DATA(cmptr);
if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
addr.in.sin_addr = *(p.a);
else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
if_index = p.s->sdl_index;
}
#endif
if (listen->family == AF_INET6)
{
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
{
union {
unsigned char *c;
struct in6_pktinfo *p;
} p;
p.c = CMSG_DATA(cmptr);
addr.in6.sin6_addr = p.p->ipi6_addr;
if_index = p.p->ipi6_ifindex;
}
}
if (!indextoname(listen->tftpfd, if_index, namebuff))
return;
name = namebuff;
addra.addr4 = addr.in.sin_addr;
if (listen->family == AF_INET6)
addra.addr6 = addr.in6.sin6_addr;
if (daemon->tftp_interfaces)
{
/* dedicated tftp interface list */
for (tmp = daemon->tftp_interfaces; tmp; tmp = tmp->next)
if (tmp->name && wildcard_match(tmp->name, name))
break;
if (!tmp)
return;
}
else
{
/* Do the same as DHCP */
if (!iface_check(listen->family, &addra, name, NULL))
{
if (!option_bool(OPT_CLEVERBIND))
enumerate_interfaces(0);
if (!loopback_exception(listen->tftpfd, listen->family, &addra, name) &&
!label_exception(if_index, listen->family, &addra))
return;
}
#ifdef HAVE_DHCP
/* allowed interfaces are the same as for DHCP */
for (tmp = daemon->dhcp_except; tmp; tmp = tmp->next)
if (tmp->name && wildcard_match(tmp->name, name))
return;
#endif
}
safe_strncpy(ifr.ifr_name, name, IF_NAMESIZE);
if (ioctl(listen->tftpfd, SIOCGIFMTU, &ifr) != -1)
{
mtu = ifr.ifr_mtu;
if (daemon->tftp_mtu != 0 && daemon->tftp_mtu < mtu)
mtu = daemon->tftp_mtu;
}
}
/* Failed to get interface mtu - can use configured value. */
if (mtu == 0)
mtu = daemon->tftp_mtu;
if (name)
{
/* check for per-interface prefix */
for (pref = daemon->if_prefix; pref; pref = pref->next)
if (strcmp(pref->interface, name) == 0)
prefix = pref->prefix;
}
if (listen->family == AF_INET)
{
addr.in.sin_port = htons(port);
#ifdef HAVE_SOCKADDR_SA_LEN
addr.in.sin_len = sizeof(addr.in);
#endif
}
else
{
addr.in6.sin6_port = htons(port);
addr.in6.sin6_flowinfo = 0;
addr.in6.sin6_scope_id = 0;
#ifdef HAVE_SOCKADDR_SA_LEN
addr.in6.sin6_len = sizeof(addr.in6);
#endif
}
if (!(transfer = whine_malloc(sizeof(struct tftp_transfer))))
return;
if ((transfer->sockfd = socket(listen->family, SOCK_DGRAM, 0)) == -1)
{
free(transfer);
return;
}
transfer->peer = peer;
transfer->timeout = now + 2;
transfer->backoff = 1;
transfer->block = 1;
transfer->blocksize = 512;
transfer->offset = 0;
transfer->file = NULL;
transfer->opt_blocksize = transfer->opt_transize = 0;
transfer->netascii = transfer->carrylf = 0;
prettyprint_addr(&peer, daemon->addrbuff);
/* if we have a nailed-down range, iterate until we find a free one. */
while (1)
{
if (bind(transfer->sockfd, &addr.sa, sa_len(&addr)) == -1 ||
#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
setsockopt(transfer->sockfd, IPPROTO_IP, IP_MTU_DISCOVER, &mtuflag, sizeof(mtuflag)) == -1 ||
#endif
!fix_fd(transfer->sockfd))
{
if (errno == EADDRINUSE && daemon->start_tftp_port != 0)
{
if (++port <= daemon->end_tftp_port)
{
if (listen->family == AF_INET)
addr.in.sin_port = htons(port);
else
addr.in6.sin6_port = htons(port);
continue;
}
my_syslog(MS_TFTP | LOG_ERR, _("unable to get free port for TFTP"));
}
free_transfer(transfer);
return;
}
break;
}
p = packet + 2;
end = packet + len;
if (ntohs(*((unsigned short *)packet)) != OP_RRQ ||
!(filename = next(&p, end)) ||
!(mode = next(&p, end)) ||
(strcasecmp(mode, "octet") != 0 && strcasecmp(mode, "netascii") != 0))
{
len = tftp_err(ERR_ILL, packet, _("unsupported request from %s"), daemon->addrbuff);
is_err = 1;
}
else
{
if (strcasecmp(mode, "netascii") == 0)
transfer->netascii = 1;
while ((opt = next(&p, end)))
{
if (strcasecmp(opt, "blksize") == 0)
{
if ((opt = next(&p, end)) && !option_bool(OPT_TFTP_NOBLOCK))
{
/* 32 bytes for IP, UDP and TFTP headers, 52 bytes for IPv6 */
int overhead = (listen->family == AF_INET) ? 32 : 52;
transfer->blocksize = atoi(opt);
if (transfer->blocksize < 1)
transfer->blocksize = 1;
if (transfer->blocksize > (unsigned)daemon->packet_buff_sz - 4)
transfer->blocksize = (unsigned)daemon->packet_buff_sz - 4;
if (mtu != 0 && transfer->blocksize > (unsigned)mtu - overhead)
transfer->blocksize = (unsigned)mtu - overhead;
transfer->opt_blocksize = 1;
transfer->block = 0;
}
}
else if (strcasecmp(opt, "tsize") == 0 && next(&p, end) && !transfer->netascii)
{
transfer->opt_transize = 1;
transfer->block = 0;
}
}
/* cope with backslashes from windows boxen. */
for (p = filename; *p; p++)
if (*p == '\\')
*p = '/';
else if (option_bool(OPT_TFTP_LC))
*p = tolower(*p);
strcpy(daemon->namebuff, "/");
if (prefix)
{
if (prefix[0] == '/')
daemon->namebuff[0] = 0;
strncat(daemon->namebuff, prefix, (MAXDNAME-1) - strlen(daemon->namebuff));
if (prefix[strlen(prefix)-1] != '/')
strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));
if (option_bool(OPT_TFTP_APREF_IP))
{
size_t oldlen = strlen(daemon->namebuff);
struct stat statbuf;
strncat(daemon->namebuff, daemon->addrbuff, (MAXDNAME-1) - strlen(daemon->namebuff));
strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));
/* remove unique-directory if it doesn't exist */
if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
daemon->namebuff[oldlen] = 0;
}
if (option_bool(OPT_TFTP_APREF_MAC))
{
unsigned char *macaddr = NULL;
unsigned char macbuf[DHCP_CHADDR_MAX];
#ifdef HAVE_DHCP
if (daemon->dhcp && peer.sa.sa_family == AF_INET)
{
/* Check if the client IP is in our lease database */
struct dhcp_lease *lease = lease_find_by_addr(peer.in.sin_addr);
if (lease && lease->hwaddr_type == ARPHRD_ETHER && lease->hwaddr_len == ETHER_ADDR_LEN)
macaddr = lease->hwaddr;
}
#endif
/* If no luck, try to find in ARP table. This only works if client is in same (V)LAN */
if (!macaddr && find_mac(&peer, macbuf, 1, now) > 0)
macaddr = macbuf;
if (macaddr)
{
size_t oldlen = strlen(daemon->namebuff);
struct stat statbuf;
snprintf(daemon->namebuff + oldlen, (MAXDNAME-1) - oldlen, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x/",
macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4], macaddr[5]);
/* remove unique-directory if it doesn't exist */
if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
daemon->namebuff[oldlen] = 0;
}
}
/* Absolute pathnames OK if they match prefix */
if (filename[0] == '/')
{
if (strstr(filename, daemon->namebuff) == filename)
daemon->namebuff[0] = 0;
else
filename++;
}
}
else if (filename[0] == '/')
daemon->namebuff[0] = 0;
strncat(daemon->namebuff, filename, (MAXDNAME-1) - strlen(daemon->namebuff));
/* check permissions and open file */
if ((transfer->file = check_tftp_fileperm(&len, prefix)))
{
if ((len = get_block(packet, transfer)) == -1)
len = tftp_err_oops(packet, daemon->namebuff);
else
is_err = 0;
}
}
while (sendto(transfer->sockfd, packet, len, 0,
(struct sockaddr *)&peer, sa_len(&peer)) == -1 && errno == EINTR);
if (is_err)
free_transfer(transfer);
else
{
transfer->next = daemon->tftp_trans;
daemon->tftp_trans = transfer;
}
}
void receive_query(struct listener *listen, time_t now)
{
struct dns_header *header = (struct dns_header *)daemon->packet;
union mysockaddr source_addr;
unsigned short type;
struct all_addr dst_addr;
struct in_addr netmask, dst_addr_4;
size_t m;
ssize_t n;
int if_index = 0;
struct iovec iov[1];
struct msghdr msg;
struct cmsghdr *cmptr;
union {
struct cmsghdr align; /* this ensures alignment */
#ifdef HAVE_IPV6
char control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
#endif
#if defined(HAVE_LINUX_NETWORK)
char control[CMSG_SPACE(sizeof(struct in_pktinfo))];
#elif defined(IP_RECVDSTADDR) && defined(HAVE_SOLARIS_NETWORK)
char control[CMSG_SPACE(sizeof(struct in_addr)) +
CMSG_SPACE(sizeof(unsigned int))];
#elif defined(IP_RECVDSTADDR)
char control[CMSG_SPACE(sizeof(struct in_addr)) +
CMSG_SPACE(sizeof(struct sockaddr_dl))];
#endif
} control_u;
/* packet buffer overwritten */
daemon->srv_save = NULL;
if (listen->iface && listen->family == AF_INET && option_bool(OPT_NOWILD))
{
dst_addr_4 = listen->iface->addr.in.sin_addr;
netmask = listen->iface->netmask;
}
else
{
dst_addr_4.s_addr = 0;
netmask.s_addr = 0;
}
iov[0].iov_base = daemon->packet;
iov[0].iov_len = daemon->edns_pktsz;
msg.msg_control = control_u.control;
msg.msg_controllen = sizeof(control_u);
msg.msg_flags = 0;
msg.msg_name = &source_addr;
msg.msg_namelen = sizeof(source_addr);
msg.msg_iov = iov;
msg.msg_iovlen = 1;
if ((n = recvmsg(listen->fd, &msg, 0)) == -1)
return;
if (n < (int)sizeof(struct dns_header) ||
(msg.msg_flags & MSG_TRUNC) ||
(header->hb3 & HB3_QR))
return;
source_addr.sa.sa_family = listen->family;
#ifdef HAVE_IPV6
if (listen->family == AF_INET6)
source_addr.in6.sin6_flowinfo = 0;
#endif
if (!option_bool(OPT_NOWILD))
{
struct ifreq ifr;
if (msg.msg_controllen < sizeof(struct cmsghdr))
return;
#if defined(HAVE_LINUX_NETWORK)
if (listen->family == AF_INET)
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
{
union {
unsigned char *c;
struct in_pktinfo *p;
} p;
p.c = CMSG_DATA(cmptr);
dst_addr_4 = dst_addr.addr.addr4 = p.p->ipi_spec_dst;
if_index = p.p->ipi_ifindex;
}
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
if (listen->family == AF_INET)
{
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
{
union {
unsigned char *c;
unsigned int *i;
struct in_addr *a;
#ifndef HAVE_SOLARIS_NETWORK
struct sockaddr_dl *s;
#endif
} p;
p.c = CMSG_DATA(cmptr);
if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
dst_addr_4 = dst_addr.addr.addr4 = *(p.a);
else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
#ifdef HAVE_SOLARIS_NETWORK
if_index = *(p.i);
#else
if_index = p.s->sdl_index;
#endif
}
}
#endif
#ifdef HAVE_IPV6
if (listen->family == AF_INET6)
{
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
{
union {
unsigned char *c;
struct in6_pktinfo *p;
} p;
p.c = CMSG_DATA(cmptr);
dst_addr.addr.addr6 = p.p->ipi6_addr;
if_index = p.p->ipi6_ifindex;
}
}
#endif
/* enforce available interface configuration */
if (!indextoname(listen->fd, if_index, ifr.ifr_name) ||
!iface_check(listen->family, &dst_addr, ifr.ifr_name))
return;
if (listen->family == AF_INET && option_bool(OPT_LOCALISE))
{
struct irec *iface;
/* get the netmask of the interface whch has the address we were sent to.
This is no neccessarily the interface we arrived on. */
for (iface = daemon->interfaces; iface; iface = iface->next)
if (iface->addr.sa.sa_family == AF_INET &&
iface->addr.in.sin_addr.s_addr == dst_addr_4.s_addr)
break;
/* interface may be new */
if (!iface)
enumerate_interfaces();
for (iface = daemon->interfaces; iface; iface = iface->next)
if (iface->addr.sa.sa_family == AF_INET &&
iface->addr.in.sin_addr.s_addr == dst_addr_4.s_addr)
break;
/* If we failed, abandon localisation */
if (iface)
netmask = iface->netmask;
else
dst_addr_4.s_addr = 0;
}
}
if (extract_request(header, (size_t)n, daemon->namebuff, &type))
{
char types[20];
querystr(types, type);
if (listen->family == AF_INET)
log_query(F_QUERY | F_IPV4 | F_FORWARD, daemon->namebuff,
(struct all_addr *)&source_addr.in.sin_addr, types);
#ifdef HAVE_IPV6
else
log_query(F_QUERY | F_IPV6 | F_FORWARD, daemon->namebuff,
(struct all_addr *)&source_addr.in6.sin6_addr, types);
#endif
}
m = answer_request (header, ((char *) header) + PACKETSZ, (size_t)n,
dst_addr_4, netmask, now);
if (m >= 1)
{
send_from(listen->fd, option_bool(OPT_NOWILD), (char *)header,
m, &source_addr, &dst_addr, if_index);
daemon->local_answer++;
}
else if (forward_query(listen->fd, &source_addr, &dst_addr, if_index,
header, (size_t)n, now, NULL))
daemon->queries_forwarded++;
else
daemon->local_answer++;
}
/* family = AF_UNSPEC finds ARP table entries.
family = AF_LOCAL finds MAC addresses. */
int iface_enumerate(int family, void *parm, int (*callback)())
{
struct sockaddr_nl addr;
struct nlmsghdr *h;
ssize_t len;
static unsigned int seq = 0;
int callback_ok = 1, newaddr = 0;
struct {
struct nlmsghdr nlh;
struct rtgenmsg g;
} req;
addr.nl_family = AF_NETLINK;
addr.nl_pad = 0;
addr.nl_groups = 0;
addr.nl_pid = 0; /* address to kernel */
again:
if (family == AF_UNSPEC)
req.nlh.nlmsg_type = RTM_GETNEIGH;
else if (family == AF_LOCAL)
req.nlh.nlmsg_type = RTM_GETLINK;
else
req.nlh.nlmsg_type = RTM_GETADDR;
req.nlh.nlmsg_len = sizeof(req);
req.nlh.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST | NLM_F_ACK;
req.nlh.nlmsg_pid = 0;
req.nlh.nlmsg_seq = ++seq;
req.g.rtgen_family = family;
/* Don't block in recvfrom if send fails */
while((len = sendto(daemon->netlinkfd, (void *)&req, sizeof(req), 0,
(struct sockaddr *)&addr, sizeof(addr))) == -1 && retry_send());
if (len == -1)
return 0;
while (1)
{
if ((len = netlink_recv()) == -1)
{
if (errno == ENOBUFS)
{
sleep(1);
goto again;
}
return 0;
}
for (h = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(h, (size_t)len); h = NLMSG_NEXT(h, len))
if (h->nlmsg_seq != seq || h->nlmsg_pid != netlink_pid || h->nlmsg_type == NLMSG_ERROR)
{
/* May be multicast arriving async */
if (nl_async(h) && option_bool(OPT_CLEVERBIND))
newaddr = 1;
}
else if (h->nlmsg_type == NLMSG_DONE)
{
/* handle async new interface address arrivals, these have to be done
after we complete as we're not re-entrant */
if (newaddr)
{
enumerate_interfaces();
create_bound_listeners(0);
}
return callback_ok;
}
else if (h->nlmsg_type == RTM_NEWADDR && family != AF_UNSPEC && family != AF_LOCAL)
{
struct ifaddrmsg *ifa = NLMSG_DATA(h);
struct rtattr *rta = IFA_RTA(ifa);
unsigned int len1 = h->nlmsg_len - NLMSG_LENGTH(sizeof(*ifa));
if (ifa->ifa_family == family)
{
if (ifa->ifa_family == AF_INET)
{
struct in_addr netmask, addr, broadcast;
netmask.s_addr = htonl(0xffffffff << (32 - ifa->ifa_prefixlen));
addr.s_addr = 0;
broadcast.s_addr = 0;
while (RTA_OK(rta, len1))
{
if (rta->rta_type == IFA_LOCAL)
addr = *((struct in_addr *)(rta+1));
else if (rta->rta_type == IFA_BROADCAST)
broadcast = *((struct in_addr *)(rta+1));
rta = RTA_NEXT(rta, len1);
}
if (addr.s_addr && callback_ok)
if (!((*callback)(addr, ifa->ifa_index, netmask, broadcast, parm)))
callback_ok = 0;
}
#ifdef HAVE_IPV6
else if (ifa->ifa_family == AF_INET6)
{
struct in6_addr *addrp = NULL;
while (RTA_OK(rta, len1))
{
if (rta->rta_type == IFA_ADDRESS)
addrp = ((struct in6_addr *)(rta+1));
rta = RTA_NEXT(rta, len1);
}
if (addrp && callback_ok)
if (!((*callback)(addrp, (int)(ifa->ifa_prefixlen), (int)(ifa->ifa_scope),
(int)(ifa->ifa_index), (int)(ifa->ifa_flags & IFA_F_TENTATIVE), parm)))
callback_ok = 0;
}
#endif
}
}
else if (h->nlmsg_type == RTM_NEWNEIGH && family == AF_UNSPEC)
{
struct ndmsg *neigh = NLMSG_DATA(h);
struct rtattr *rta = NDA_RTA(neigh);
unsigned int len1 = h->nlmsg_len - NLMSG_LENGTH(sizeof(*neigh));
size_t maclen = 0;
char *inaddr = NULL, *mac = NULL;
while (RTA_OK(rta, len1))
{
if (rta->rta_type == NDA_DST)
inaddr = (char *)(rta+1);
else if (rta->rta_type == NDA_LLADDR)
{
maclen = rta->rta_len - sizeof(struct rtattr);
mac = (char *)(rta+1);
}
rta = RTA_NEXT(rta, len1);
}
if (inaddr && mac && callback_ok)
if (!((*callback)(neigh->ndm_family, inaddr, mac, maclen, parm)))
callback_ok = 0;
}
#ifdef HAVE_DHCP6
else if (h->nlmsg_type == RTM_NEWLINK && family == AF_LOCAL)
{
struct ifinfomsg *link = NLMSG_DATA(h);
struct rtattr *rta = IFLA_RTA(link);
unsigned int len1 = h->nlmsg_len - NLMSG_LENGTH(sizeof(*link));
char *mac = NULL;
size_t maclen = 0;
while (RTA_OK(rta, len1))
{
if (rta->rta_type == IFLA_ADDRESS)
{
maclen = rta->rta_len - sizeof(struct rtattr);
mac = (char *)(rta+1);
}
rta = RTA_NEXT(rta, len1);
}
if (mac && callback_ok && !((link->ifi_flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) &&
!((*callback)((int)link->ifi_index, (unsigned int)link->ifi_type, mac, maclen, parm)))
callback_ok = 0;
}
#endif
}
}
