void
bootp(struct packet *packet)
{
struct host_decl *hp, *host = NULL;
struct packet outgoing;
struct dhcp_packet raw;
struct sockaddr_in to;
struct in_addr from;
struct tree_cache *options[256];
struct subnet *subnet = NULL;
struct lease *lease;
struct iaddr ip_address;
int i;
if (packet->raw->op != BOOTREQUEST)
return;
note("BOOTREQUEST from %s via %s%s", print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ? inet_ntoa(packet->raw->giaddr) :
packet->interface->name,
packet->options_valid ? "" : " (non-rfc1048)");
if (!locate_network(packet))
return;
hp = find_hosts_by_haddr(packet->raw->htype, packet->raw->chaddr,
packet->raw->hlen);
lease = find_lease(packet, packet->shared_network, 0);
/*
* Find an IP address in the host_decl that matches the specified
* network.
*/
if (hp)
subnet = find_host_for_network(&hp, &ip_address,
packet->shared_network);
if (!subnet) {
/*
* We didn't find an applicable host declaration. Just in case
* we may be able to dynamically assign an address, see if
* there's a host declaration that doesn't have an ip address
* associated with it.
*/
if (hp)
for (; hp; hp = hp->n_ipaddr)
if (!hp->fixed_addr) {
host = hp;
break;
}
if (host && (!host->group->allow_booting)) {
note("Ignoring excluded BOOTP client %s", host->name ?
host->name : print_hw_addr (packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr));
return;
}
if (host && (!host->group->allow_bootp)) {
note("Ignoring BOOTP request from client %s",
host->name ? host->name :
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr));
return;
}
/*
* If we've been told not to boot unknown clients, and we didn't
* find any host record for this client, ignore it.
*/
if (!host &&
!(packet->shared_network->group->boot_unknown_clients)) {
note("Ignoring unknown BOOTP client %s via %s",
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) :
packet->interface->name);
return;
}
/*
* If we've been told not to boot with bootp on this network,
* ignore it.
*/
if (!host &&
!(packet->shared_network->group->allow_bootp)) {
note("Ignoring BOOTP request from client %s via %s",
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) :
packet->interface->name);
return;
}
/*
* If the packet is from a host we don't know and there are no
* dynamic bootp addresses on the network it came in on, drop
* it on the floor.
*/
if (!(packet->shared_network->group->dynamic_bootp)) {
lose:
note("No applicable record for BOOTP host %s via %s",
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) :
packet->interface->name);
return;
}
/*
* If a lease has already been assigned to this client and it's
* still okay to use dynamic bootp on that lease, reassign it.
*/
if (lease) {
/*
* If this lease can be used for dynamic bootp, do so.
*/
if ((lease->flags & DYNAMIC_BOOTP_OK)) {
/*
* If it's not a DYNAMIC_BOOTP lease, release it
* before reassigning it so that we don't get a
* lease conflict.
*/
if (!(lease->flags & BOOTP_LEASE))
release_lease(lease);
lease->host = host;
ack_lease(packet, lease, 0, 0);
return;
}
/*
* If dynamic BOOTP is no longer allowed for this
* lease, set it free.
*/
release_lease(lease);
}
/*
* If there are dynamic bootp addresses that might be
* available, try to snag one.
*/
for (lease = packet->shared_network->last_lease;
lease && lease->ends <= cur_time;
lease = lease->prev) {
if ((lease->flags & DYNAMIC_BOOTP_OK)) {
lease->host = host;
ack_lease(packet, lease, 0, 0);
return;
}
}
goto lose;
}
/* Make sure we're allowed to boot this client. */
if (hp && (!hp->group->allow_booting)) {
note("Ignoring excluded BOOTP client %s", hp->name);
return;
}
/* Make sure we're allowed to boot this client with bootp. */
if (hp && (!hp->group->allow_bootp)) {
note("Ignoring BOOTP request from client %s", hp->name);
return;
}
/* Set up the outgoing packet... */
memset(&outgoing, 0, sizeof outgoing);
memset(&raw, 0, sizeof raw);
outgoing.raw = &raw;
/*
* If we didn't get a known vendor magic number on the way in, just
* copy the input options to the output.
*/
if (!packet->options_valid && !subnet->group->always_reply_rfc1048 &&
(!hp || !hp->group->always_reply_rfc1048)) {
memcpy(outgoing.raw->options, packet->raw->options,
DHCP_OPTION_LEN);
outgoing.packet_length = BOOTP_MIN_LEN;
} else {
struct tree_cache netmask_tree; /* -- RBF */
/*
* Come up with a list of options that we want to send to this
* client. Start with the per-subnet options, and then override
* those with client-specific options.
*/
memcpy(options, subnet->group->options, sizeof(options));
for (i = 0; i < 256; i++)
if (hp->group->options[i])
options[i] = hp->group->options[i];
/*
* Use the subnet mask from the subnet declaration if no other
* mask has been provided.
*/
if (!options[DHO_SUBNET_MASK]) {
options[DHO_SUBNET_MASK] = &netmask_tree;
netmask_tree.flags = TC_TEMPORARY;
netmask_tree.value = lease->subnet->netmask.iabuf;
netmask_tree.len = lease->subnet->netmask.len;
netmask_tree.buf_size = lease->subnet->netmask.len;
netmask_tree.timeout = -1;
netmask_tree.tree = NULL;
}
/*
* Pack the options into the buffer. Unlike DHCP, we can't pack
* options into the filename and server name buffers.
*/
outgoing.packet_length = cons_options(packet, outgoing.raw,
0, options, 0, 0, 1, NULL, 0);
if (outgoing.packet_length < BOOTP_MIN_LEN)
outgoing.packet_length = BOOTP_MIN_LEN;
}
/* Take the fields that we care about... */
raw.op = BOOTREPLY;
raw.htype = packet->raw->htype;
raw.hlen = packet->raw->hlen;
memcpy(raw.chaddr, packet->raw->chaddr, sizeof(raw.chaddr));
raw.hops = packet->raw->hops;
raw.xid = packet->raw->xid;
raw.secs = packet->raw->secs;
raw.flags = packet->raw->flags;
raw.ciaddr = packet->raw->ciaddr;
memcpy(&raw.yiaddr, ip_address.iabuf, sizeof(raw.yiaddr));
/* Figure out the address of the next server. */
if (hp && hp->group->next_server.len)
memcpy(&raw.siaddr, hp->group->next_server.iabuf, 4);
else if (subnet->group->next_server.len)
memcpy(&raw.siaddr, subnet->group->next_server.iabuf, 4);
else if (subnet->interface_address.len)
memcpy(&raw.siaddr, subnet->interface_address.iabuf, 4);
else
raw.siaddr = packet->interface->primary_address;
raw.giaddr = packet->raw->giaddr;
if (hp->group->server_name)
strncpy(raw.sname, hp->group->server_name, sizeof(raw.sname));
else if (subnet->group->server_name)
strncpy(raw.sname, subnet->group->server_name,
sizeof(raw.sname));
if (hp->group->filename)
strncpy(raw.file, hp->group->filename, sizeof(raw.file));
else if (subnet->group->filename)
strncpy(raw.file, subnet->group->filename, sizeof(raw.file));
else
memcpy(raw.file, packet->raw->file, sizeof(raw.file));
from = packet->interface->primary_address;
/* Report what we're doing... */
note("BOOTREPLY for %s to %s (%s) via %s", piaddr(ip_address),
hp->name, print_hw_addr(packet->raw->htype, packet->raw->hlen,
packet->raw->chaddr), packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) : packet->interface->name);
/* Set up the parts of the address that are in common. */
memset(&to, 0, sizeof(to));
to.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
to.sin_len = sizeof(to);
#endif
/* If this was gatewayed, send it back to the gateway... */
if (raw.giaddr.s_addr) {
to.sin_addr = raw.giaddr;
to.sin_port = server_port;
(void) send_packet(packet->interface, &raw,
outgoing.packet_length, from, &to, packet->haddr);
return;
}
/*
* If it comes from a client that already knows its address and is not
* requesting a broadcast response, and we can unicast to a client
* without using the ARP protocol, sent it directly to that client.
*/
else if (!(raw.flags & htons(BOOTP_BROADCAST))) {
to.sin_addr = raw.yiaddr;
to.sin_port = client_port;
} else {
/* Otherwise, broadcast it on the local network. */
to.sin_addr.s_addr = INADDR_BROADCAST;
to.sin_port = client_port; /* XXX */
}
errno = 0;
(void) send_packet(packet->interface, &raw,
outgoing.packet_length, from, &to, packet->haddr);
}
/*! \brief Lease file parser. The parser can only read ISC DHCPD
* dhcpd.leases file format. */
int parse_leases(void)
{
FILE *dhcpd_leases;
char *line, *ipstring, macstring[20];
union ipaddr_t addr;
struct stat lease_file_stats;
bool ethernets = false;
struct leases_t *lease;
dhcpd_leases = fopen(config.dhcpdlease_file, "r");
if (dhcpd_leases == NULL) {
err(EXIT_FAILURE, "parse_leases: %s", config.dhcpdlease_file);
}
#ifdef HAVE_POSIX_FADVISE
# ifdef POSIX_FADV_WILLNEED
posix_fadvise(fileno(dhcpd_leases), 0, 0, POSIX_FADV_WILLNEED);
if (errno) {
err(EXIT_FAILURE, "parse_leases: fadvise %s",
config.dhcpdlease_file);
}
# endif /* POSIX_FADV_WILLNEED */
# ifdef POSIX_FADV_SEQUENTIAL
posix_fadvise(fileno(dhcpd_leases), 0, 0, POSIX_FADV_SEQUENTIAL);
if (errno) {
err(EXIT_FAILURE, "parse_leases: fadvise %s",
config.dhcpdlease_file);
}
# endif /* POSIX_FADV_SEQUENTIAL */
#endif /* HAVE_POSIX_FADVISE */
/* I found out that there's one lease address per 300 bytes in
* dhcpd.leases file. Malloc is little bit pessimistic and uses 250.
* If someone has higher density in lease file I'm interested to
* hear about that. */
if (stat(config.dhcpdlease_file, &lease_file_stats)) {
err(EXIT_FAILURE, "parse_leases: %s", config.dhcpdlease_file);
}
line = xmalloc(sizeof(char) * MAXLEN);
ipstring = xmalloc(sizeof(char) * MAXLEN);
if (config.output_format[0] == 'X' || config.output_format[0] == 'J') {
ethernets = true;
}
const char **p = prefixes[config.dhcp_version];
int *l = prefix_length[config.dhcp_version];
/*! \def HAS_PREFIX(line, type)
* \brief A macro to match IPv4 and IPv6 lease lines.
*
* FIXME: This macro should have better name. The HAS_PREFIX sounds like
* some sort of prefix length test. */
#define HAS_PREFIX(line, type) xstrstr((line), p[type], l[type])
while (!feof(dhcpd_leases)) {
if (!fgets(line, MAXLEN, dhcpd_leases) && ferror(dhcpd_leases)) {
err(EXIT_FAILURE, "parse_leases: %s",
config.dhcpdlease_file);
}
/* It's a lease, save IP */
if (HAS_PREFIX(line, PREFIX_LEASE)) {
nth_field(ipstring, line + l[PREFIX_LEASE]);
parse_ipaddr(ipstring, &addr);
continue;
}
if (HAS_PREFIX(line, PREFIX_BINDING_STATE_FREE) ||
HAS_PREFIX(line, PREFIX_BINDING_STATE_ABANDONED) ||
HAS_PREFIX(line, PREFIX_BINDING_STATE_EXPIRED) ||
HAS_PREFIX(line, PREFIX_BINDING_STATE_RELEASED)) {
/* remove old entry, if exists */
if ((lease = find_lease(&addr)) != NULL) {
delete_lease(lease);
}
add_lease(&addr, FREE);
continue;
}
/* Copy IP to correct array */
if (HAS_PREFIX(line, PREFIX_BINDING_STATE_ACTIVE)) {
/* remove old entry, if exists */
if ((lease = find_lease(&addr)) != NULL) {
delete_lease(lease);
}
add_lease(&addr, ACTIVE);
continue;
}
if (HAS_PREFIX(line, PREFIX_BINDING_STATE_BACKUP)) {
/* remove old entry, if exists */
if ((lease = find_lease(&addr)) != NULL) {
delete_lease(lease);
}
add_lease(&addr, BACKUP);
config.backups_found = true;
continue;
}
if (ethernets && (xstrstr(line, " hardware ethernet", 19))) {
nth_field(macstring, line + 20);
macstring[17] = '\0';
if ((lease = find_lease(&addr)) != NULL) {
lease->ethernet = xstrdup(macstring);
}
}
}
#undef HAS_PREFIX
free(line);
free(ipstring);
fclose(dhcpd_leases);
return 0;
}
