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|
/**
* Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
* Copyright (C) 2016 Hans Dedecker <dedeckeh@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License v2 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*
*/
#include <time.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <stddef.h>
#include <stdlib.h>
#include <resolv.h>
#include <limits.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/ip.h>
#include <sys/ioctl.h>
#include <sys/timerfd.h>
#include <arpa/inet.h>
#include "odhcpd.h"
#include "dhcpv4.h"
#include "dhcpv6.h"
static void free_dhcpv4_assignment(struct dhcpv4_assignment *a);
static void handle_dhcpv4(void *addr, void *data, size_t len,
struct interface *iface, void *dest_addr);
static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
enum dhcpv4_msg msg, const uint8_t *mac, struct in_addr reqaddr,
uint32_t *leasetime, const char *hostname, const size_t hostname_len);
/* Create socket and register events */
int init_dhcpv4(void)
{
return 0;
}
int setup_dhcpv4_interface(struct interface *iface, bool enable)
{
if (iface->dhcpv4_event.uloop.fd > 0) {
uloop_fd_delete(&iface->dhcpv4_event.uloop);
close(iface->dhcpv4_event.uloop.fd);
iface->dhcpv4_event.uloop.fd = -1;
}
if (iface->dhcpv4 && enable) {
if (!iface->dhcpv4_assignments.next)
INIT_LIST_HEAD(&iface->dhcpv4_assignments);
int sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
if (sock < 0) {
syslog(LOG_ERR, "Failed to create DHCPv4 server socket: %s",
strerror(errno));
return -1;
}
/* Basic IPv4 configuration */
int val = 1;
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &val, sizeof(val));
setsockopt(sock, IPPROTO_IP, IP_PKTINFO, &val, sizeof(val));
val = IPTOS_PREC_INTERNETCONTROL;
setsockopt(sock, IPPROTO_IP, IP_TOS, &val, sizeof(val));
val = IP_PMTUDISC_DONT;
setsockopt(sock, IPPROTO_IP, IP_MTU_DISCOVER, &val, sizeof(val));
setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE,
iface->ifname, strlen(iface->ifname));
struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT),
{INADDR_ANY}, {0}};
if (bind(sock, (struct sockaddr*)&bind_addr, sizeof(bind_addr))) {
syslog(LOG_ERR, "Failed to open DHCPv4 server socket: %s",
strerror(errno));
return -1;
}
if (ntohl(iface->dhcpv4_start.s_addr) > ntohl(iface->dhcpv4_end.s_addr)) {
syslog(LOG_ERR, "Invalid DHCP range");
return -1;
}
/* Create a range if not specified */
struct ifreq ifreq;
strncpy(ifreq.ifr_name, iface->ifname, sizeof(ifreq.ifr_name));
struct sockaddr_in *saddr = (struct sockaddr_in*)&ifreq.ifr_addr;
struct sockaddr_in *smask = (struct sockaddr_in*)&ifreq.ifr_netmask;
if (!(iface->dhcpv4_start.s_addr & htonl(0xffff0000)) &&
!(iface->dhcpv4_end.s_addr & htonl(0xffff0000)) &&
!ioctl(sock, SIOCGIFADDR, &ifreq)) {
struct in_addr addr = saddr->sin_addr;
ioctl(sock, SIOCGIFNETMASK, &ifreq);
struct in_addr mask = smask->sin_addr;
uint32_t start = ntohl(iface->dhcpv4_start.s_addr);
uint32_t end = ntohl(iface->dhcpv4_end.s_addr);
if (start && end && start < end &&
start > ntohl(addr.s_addr & ~mask.s_addr) &&
(start & ntohl(~mask.s_addr)) == start &&
(end & ntohl(~mask.s_addr)) == end) {
iface->dhcpv4_start.s_addr = htonl(start) |
(addr.s_addr & mask.s_addr);
iface->dhcpv4_end.s_addr = htonl(end) |
(addr.s_addr & mask.s_addr);
} else if (ntohl(mask.s_addr) <= 0xfffffff0) {
start = addr.s_addr & mask.s_addr;
end = addr.s_addr & mask.s_addr;
if (ntohl(mask.s_addr) <= 0xffffff00) {
iface->dhcpv4_start.s_addr = start | htonl(100);
iface->dhcpv4_end.s_addr = end | htonl(250);
} else if (ntohl(mask.s_addr) <= 0xffffffc0) {
iface->dhcpv4_start.s_addr = start | htonl(10);
iface->dhcpv4_end.s_addr = end | htonl(60);
} else if (ntohl(mask.s_addr) <= 0xffffffe0) {
iface->dhcpv4_start.s_addr = start | htonl(10);
iface->dhcpv4_end.s_addr = end | htonl(30);
} else {
iface->dhcpv4_start.s_addr = start | htonl(3);
iface->dhcpv4_end.s_addr = end | htonl(12);
}
}
}
/* Parse static entries */
struct lease *lease;
list_for_each_entry(lease, &leases, head) {
/* Construct entry */
struct dhcpv4_assignment *a = calloc(1, sizeof(*a));
if (!a) {
syslog(LOG_ERR, "Calloc failed for static lease on interface %s",
iface->ifname);
return -1;
}
a->leasetime = lease->dhcpv4_leasetime;
a->addr = ntohl(lease->ipaddr.s_addr);
memcpy(a->hwaddr, lease->mac.ether_addr_octet, sizeof(a->hwaddr));
/* Static assignment */
a->flags |= OAF_STATIC;
/* Infinite valid */
a->valid_until = 0;
/* Assign to all interfaces */
struct dhcpv4_assignment *c;
list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
if (c->addr > a->addr) {
list_add_tail(&a->head, &c->head);
break;
} else if (c->addr == a->addr)
/* Already an assignment with that number */
break;
}
if (&c->head == &iface->dhcpv4_assignments)
list_add(&a->head, &iface->dhcpv4_assignments);
if (a->head.next) {
if (lease->hostname[0]) {
free(a->hostname);
a->hostname = strdup(lease->hostname);
}
} else
free_dhcpv4_assignment(a);
}
// Clean invalid assignments
struct dhcpv4_assignment *a, *n;
list_for_each_entry_safe(a, n, &iface->dhcpv4_assignments, head) {
if ((htonl(a->addr) & smask->sin_addr.s_addr) !=
(iface->dhcpv4_start.s_addr & smask->sin_addr.s_addr))
free_dhcpv4_assignment(a);
}
iface->dhcpv4_event.uloop.fd = sock;
iface->dhcpv4_event.handle_dgram = handle_dhcpv4;
odhcpd_register(&iface->dhcpv4_event);
} else if (iface->dhcpv4_assignments.next) {
while (!list_empty(&iface->dhcpv4_assignments))
free_dhcpv4_assignment(list_first_entry(&iface->dhcpv4_assignments,
struct dhcpv4_assignment, head));
}
return 0;
}
static char *dhcpv4_msg_to_string(uint8_t reqmsg)
{
switch (reqmsg) {
case (DHCPV4_MSG_DISCOVER):
return "DHCPV4_MSG_DISCOVER";
case (DHCPV4_MSG_OFFER):
return "DHCPV4_MSG_OFFER";
case (DHCPV4_MSG_REQUEST):
return "DHCPV4_MSG_REQUEST";
case (DHCPV4_MSG_DECLINE):
return "DHCPV4_MSG_DECLINE";
case (DHCPV4_MSG_ACK):
return "DHCPV4_MSG_ACK";
case (DHCPV4_MSG_NAK):
return "DHCPV4_MSG_NAK";
case (DHCPV4_MSG_RELEASE):
return "DHCPV4_MSG_RELEASE";
case (DHCPV4_MSG_INFORM):
return "DHCPV4_MSG_INFORM";
default:
return "UNKNOWN";
}
}
static void free_dhcpv4_assignment(struct dhcpv4_assignment *a)
{
if (a->head.next)
list_del(&a->head);
free(a->hostname);
free(a);
}
static void dhcpv4_put(struct dhcpv4_message *msg, uint8_t **cookie,
uint8_t type, uint8_t len, const void *data)
{
uint8_t *c = *cookie;
if (*cookie + 2 + len > (uint8_t*)&msg[1])
return;
*c++ = type;
*c++ = len;
memcpy(c, data, len);
*cookie = c + len;
}
// Handler for DHCPv4 messages
static void handle_dhcpv4(void *addr, void *data, size_t len,
struct interface *iface, _unused void *dest_addr)
{
if (!iface->dhcpv4)
return;
struct dhcpv4_message *req = data;
if (len < offsetof(struct dhcpv4_message, options) + 4 ||
req->op != DHCPV4_BOOTREQUEST || req->hlen != 6)
return;
int sock = iface->dhcpv4_event.uloop.fd;
struct sockaddr_in ifaddr;
struct sockaddr_in ifnetmask;
syslog(LOG_NOTICE, "Got DHCPv4 request");
struct ifreq ifreq;
memcpy(ifreq.ifr_name, iface->ifname, sizeof(ifreq.ifr_name));
if (ioctl(sock, SIOCGIFADDR, &ifreq)) {
syslog(LOG_WARNING, "DHCPv4 failed to detect address: %s", strerror(errno));
return;
}
memcpy(&ifaddr, &ifreq.ifr_addr, sizeof(ifaddr));
if (ioctl(sock, SIOCGIFNETMASK, &ifreq))
return;
memcpy(&ifnetmask, &ifreq.ifr_netmask, sizeof(ifnetmask));
uint32_t network = ifaddr.sin_addr.s_addr & ifnetmask.sin_addr.s_addr;
if ((iface->dhcpv4_start.s_addr & ifnetmask.sin_addr.s_addr) != network ||
(iface->dhcpv4_end.s_addr & ifnetmask.sin_addr.s_addr) != network) {
syslog(LOG_WARNING, "DHCPv4 range out of assigned network");
return;
}
struct ifreq ifr = {.ifr_name = ""};
strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name));
struct dhcpv4_message reply = {
.op = DHCPV4_BOOTREPLY,
.htype = 1,
.hlen = 6,
.hops = 0,
.xid = req->xid,
.secs = 0,
.flags = req->flags,
.ciaddr = {INADDR_ANY},
.giaddr = req->giaddr,
.siaddr = ifaddr.sin_addr,
};
memcpy(reply.chaddr, req->chaddr, sizeof(reply.chaddr));
reply.options[0] = 0x63;
reply.options[1] = 0x82;
reply.options[2] = 0x53;
reply.options[3] = 0x63;
uint8_t *cookie = &reply.options[4];
uint8_t reqmsg = DHCPV4_MSG_REQUEST;
uint8_t msg = DHCPV4_MSG_ACK;
struct in_addr reqaddr = {INADDR_ANY};
uint32_t leasetime = 0;
size_t hostname_len = 0;
char hostname[256];
uint8_t *start = &req->options[4];
uint8_t *end = ((uint8_t*)data) + len;
struct dhcpv4_option *opt;
dhcpv4_for_each_option(start, end, opt) {
if (opt->type == DHCPV4_OPT_MESSAGE && opt->len == 1)
reqmsg = opt->data[0];
else if (opt->type == DHCPV4_OPT_HOSTNAME && opt->len > 0) {
hostname_len = opt->len;
memcpy(hostname, opt->data, hostname_len);
hostname[hostname_len] = 0;
} else if (opt->type == DHCPV4_OPT_IPADDRESS && opt->len == 4)
memcpy(&reqaddr, opt->data, 4);
else if (opt->type == DHCPV4_OPT_SERVERID && opt->len == 4) {
if (memcmp(opt->data, &ifaddr.sin_addr, 4))
return;
} else if (iface->filter_class && opt->type == DHCPV4_OPT_USER_CLASS) {
uint8_t *c = opt->data, *cend = &opt->data[opt->len];
for (; c < cend && &c[*c] < cend; c = &c[1 + *c]) {
size_t elen = strlen(iface->filter_class);
if (*c == elen && !memcmp(&c[1], iface->filter_class, elen))
return; // Ignore from homenet
}
} else if (opt->type == DHCPV4_OPT_LEASETIME && opt->len == 4)
memcpy(&leasetime, opt->data, 4);
}
if (reqmsg != DHCPV4_MSG_DISCOVER && reqmsg != DHCPV4_MSG_REQUEST &&
reqmsg != DHCPV4_MSG_INFORM && reqmsg != DHCPV4_MSG_DECLINE &&
reqmsg != DHCPV4_MSG_RELEASE)
return;
struct dhcpv4_assignment *lease = NULL;
if (reqmsg != DHCPV4_MSG_INFORM)
lease = dhcpv4_lease(iface, reqmsg, req->chaddr, reqaddr,
&leasetime, hostname, hostname_len);
if (!lease) {
if (reqmsg == DHCPV4_MSG_REQUEST)
msg = DHCPV4_MSG_NAK;
else if (reqmsg == DHCPV4_MSG_DISCOVER)
return;
} else if (reqmsg == DHCPV4_MSG_DISCOVER)
msg = DHCPV4_MSG_OFFER;
else if (reqmsg == DHCPV4_MSG_REQUEST && reqaddr.s_addr &&
reqaddr.s_addr != htonl(lease->addr)) {
msg = DHCPV4_MSG_NAK;
/*
* DHCP client requested an IP which we can't offer to him. Probably the
* client changed the network. The reply type is set to DHCPV4_MSG_NAK,
* because the client should not use that IP.
*
* For modern devices we build an answer that includes a valid IP, like
* a DHCPV4_MSG_ACK. The client will use that IP and doesn't need to
* perform additional DHCP round trips.
*
*/
}
syslog(LOG_WARNING, "received %s from %02x:%02x:%02x:%02x:%02x:%02x",
dhcpv4_msg_to_string(reqmsg),
req->chaddr[0],req->chaddr[1],req->chaddr[2],
req->chaddr[3],req->chaddr[4],req->chaddr[5]);
if (reqmsg == DHCPV4_MSG_DECLINE || reqmsg == DHCPV4_MSG_RELEASE)
return;
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_MESSAGE, 1, &msg);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_SERVERID, 4, &ifaddr.sin_addr);
if (lease) {
uint32_t val;
reply.yiaddr.s_addr = htonl(lease->addr);
val = htonl(leasetime);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_LEASETIME, 4, &val);
if (leasetime != UINT32_MAX) {
val = htonl(500 * leasetime / 1000);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_RENEW, 4, &val);
val = htonl(875 * leasetime / 1000);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_REBIND, 4, &val);
}
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_NETMASK, 4, &ifnetmask.sin_addr);
if (lease->hostname)
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_HOSTNAME,
strlen(lease->hostname), lease->hostname);
if (!ioctl(sock, SIOCGIFBRDADDR, &ifr)) {
struct sockaddr_in *ina = (struct sockaddr_in*)&ifr.ifr_broadaddr;
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_BROADCAST, 4, &ina->sin_addr);
}
}
if (!ioctl(sock, SIOCGIFMTU, &ifr)) {
uint16_t mtu = htons(ifr.ifr_mtu);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_MTU, 2, &mtu);
}
if (iface->search && iface->search_len <= 255)
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_SEARCH_DOMAIN,
iface->search_len, iface->search);
else if (!res_init() && _res.dnsrch[0] && _res.dnsrch[0][0]) {
uint8_t search_buf[256];
int len = dn_comp(_res.dnsrch[0], search_buf,
sizeof(search_buf), NULL, NULL);
if (len > 0)
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_SEARCH_DOMAIN,
len, search_buf);
}
if (iface->dhcpv4_router_cnt == 0)
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_ROUTER, 4, &ifaddr.sin_addr);
else
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_ROUTER,
4 * iface->dhcpv4_router_cnt, iface->dhcpv4_router);
if (iface->dhcpv4_dns_cnt == 0)
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_DNSSERVER, 4, &ifaddr.sin_addr);
else
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_DNSSERVER,
4 * iface->dhcpv4_dns_cnt, iface->dhcpv4_dns);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_END, 0, NULL);
struct sockaddr_in dest = *((struct sockaddr_in*)addr);
if (req->giaddr.s_addr) {
/*
* relay agent is configured, send reply to the agent
*/
dest.sin_addr = req->giaddr;
dest.sin_port = htons(DHCPV4_SERVER_PORT);
} else if (req->ciaddr.s_addr && req->ciaddr.s_addr != dest.sin_addr.s_addr) {
/*
* client has existing configuration (ciaddr is set) AND this address is
* not the address it used for the dhcp message
*/
dest.sin_addr = req->ciaddr;
dest.sin_port = htons(DHCPV4_CLIENT_PORT);
} else if ((ntohs(req->flags) & DHCPV4_FLAG_BROADCAST) ||
req->hlen != reply.hlen || !reply.yiaddr.s_addr) {
/*
* client requests a broadcast reply OR we can't offer an IP
*/
dest.sin_addr.s_addr = INADDR_BROADCAST;
dest.sin_port = htons(DHCPV4_CLIENT_PORT);
} else if (!req->ciaddr.s_addr && msg == DHCPV4_MSG_NAK) {
/*
* client has no previous configuration -> no IP, so we need to reply
* with a broadcast packet
*/
dest.sin_addr.s_addr = INADDR_BROADCAST;
dest.sin_port = htons(DHCPV4_CLIENT_PORT);
} else {
/*
* send reply to the newly (in this proccess) allocated IP
*/
dest.sin_addr = reply.yiaddr;
dest.sin_port = htons(DHCPV4_CLIENT_PORT);
struct arpreq arp = {.arp_flags = ATF_COM};
memcpy(arp.arp_ha.sa_data, req->chaddr, 6);
memcpy(&arp.arp_pa, &dest, sizeof(arp.arp_pa));
memcpy(arp.arp_dev, iface->ifname, sizeof(arp.arp_dev));
ioctl(sock, SIOCSARP, &arp);
}
if (dest.sin_addr.s_addr == INADDR_BROADCAST)
/* reply goes to IP broadcast -> MAC broadcast */
syslog(LOG_WARNING, "sending %s to ff:ff:ff:ff:ff:ff - %s",
dhcpv4_msg_to_string(msg),
inet_ntoa(dest.sin_addr));
else
/*
* reply is send directly to IP,
* MAC is assumed to be the same as the request
*/
syslog(LOG_WARNING, "sending %s to %02x:%02x:%02x:%02x:%02x:%02x - %s",
dhcpv4_msg_to_string(msg),
req->chaddr[0],req->chaddr[1],req->chaddr[2],
req->chaddr[3],req->chaddr[4],req->chaddr[5],
inet_ntoa(dest.sin_addr));
sendto(sock, &reply, sizeof(reply), MSG_DONTWAIT,
(struct sockaddr*)&dest, sizeof(dest));
}
static bool dhcpv4_test(struct interface *iface, uint32_t try)
{
struct dhcpv4_assignment *c;
list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
if (c->addr == try)
return false;
}
return true;
}
static bool dhcpv4_assign(struct interface *iface,
struct dhcpv4_assignment *assign, uint32_t raddr)
{
uint32_t start = ntohl(iface->dhcpv4_start.s_addr);
uint32_t end = ntohl(iface->dhcpv4_end.s_addr);
uint32_t count = end - start + 1;
// try to assign the IP the client asked for
if (start <= raddr && raddr <= end && dhcpv4_test(iface, raddr)) {
assign->addr = raddr;
list_add(&assign->head, &iface->dhcpv4_assignments);
syslog(LOG_INFO, "assigning the IP the client asked for: %u.%u.%u.%u",
(assign->addr & 0xff000000) >> 24,
(assign->addr & 0x00ff0000) >> 16,
(assign->addr & 0x0000ff00) >> 8,
(assign->addr & 0x000000ff));
return true;
}
// Seed RNG with checksum of hwaddress
uint32_t seed = 0;
for (size_t i = 0; i < sizeof(assign->hwaddr); ++i) {
// Knuth's multiplicative method
uint8_t o = assign->hwaddr[i];
seed += (o*2654435761) % UINT32_MAX;
}
srand(seed);
uint32_t try = (((uint32_t)rand()) % count) + start;
if (list_empty(&iface->dhcpv4_assignments)) {
assign->addr = try;
list_add(&assign->head, &iface->dhcpv4_assignments);
syslog(LOG_INFO, "assigning mapped IP (empty list): %u.%u.%u.%u",
(assign->addr & 0xff000000) >> 24,
(assign->addr & 0x00ff0000) >> 16,
(assign->addr & 0x0000ff00) >> 8,
(assign->addr & 0x000000ff));
return true;
}
for (uint32_t i = 0; i < count; ++i) {
if (dhcpv4_test(iface, try)) {
/* test was successful: IP address is not assigned, assign it */
assign->addr = try;
list_add(&assign->head, &iface->dhcpv4_assignments);
syslog(LOG_DEBUG, "assigning mapped IP: %u.%u.%u.%u (try %u of %u)",
(assign->addr & 0xff000000) >> 24,
(assign->addr & 0x00ff0000) >> 16,
(assign->addr & 0x0000ff00) >> 8,
(assign->addr & 0x000000ff), i, count);
return true;
}
try = (((try - start) + 1) % count) + start;
}
syslog(LOG_WARNING, "can't assign any IP address -> address space is full");
return false;
}
static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
enum dhcpv4_msg msg, const uint8_t *mac, struct in_addr reqaddr,
uint32_t *leasetime, const char *hostname, const size_t hostname_len)
{
struct dhcpv4_assignment *lease = NULL;
uint32_t raddr = ntohl(reqaddr.s_addr);
time_t now = odhcpd_time();
struct dhcpv4_assignment *c, *n, *a = NULL;
list_for_each_entry_safe(c, n, &iface->dhcpv4_assignments, head) {
if (!memcmp(c->hwaddr, mac, 6)) {
a = c;
if (c->addr == raddr)
break;
} else if (!INFINITE_VALID(c->valid_until) && c->valid_until < now)
free_dhcpv4_assignment(c);
}
if (msg == DHCPV4_MSG_DISCOVER || msg == DHCPV4_MSG_REQUEST) {
bool assigned = !!a;
uint32_t my_leasetime;
if (!a && !iface->no_dynamic_dhcp) {
/* Create new binding */
a = calloc(1, sizeof(*a));
if (!a) {
syslog(LOG_ERR, "Failed to calloc binding on interface %s", iface->ifname);
return NULL;
}
memcpy(a->hwaddr, mac, sizeof(a->hwaddr));
/* Don't consider new assignment as infinite */
a->valid_until = now;
assigned = dhcpv4_assign(iface, a, raddr);
}
if (a->leasetime)
my_leasetime = a->leasetime;
else
my_leasetime = iface->dhcpv4_leasetime;
if ((*leasetime == 0) || (my_leasetime < *leasetime))
*leasetime = my_leasetime;
if (assigned) {
if (msg == DHCPV4_MSG_DISCOVER) {
a->flags &= ~OAF_BOUND;
if (!(a->flags & OAF_STATIC))
a->valid_until = now;
} else {
if (hostname_len > 0) {
a->hostname = realloc(a->hostname, hostname_len + 1);
if (a->hostname) {
memcpy(a->hostname, hostname, hostname_len);
a->hostname[hostname_len] = 0;
}
}
a->flags |= OAF_BOUND;
if (!(a->flags & OAF_STATIC))
a->valid_until = ((*leasetime == UINT32_MAX) ? 0 : (time_t)(now + *leasetime));
}
} else if (!assigned && a) {
/* Cleanup failed assignment */
free_dhcpv4_assignment(a);
a = NULL;
}
if (assigned && a)
lease = a;
} else if (msg == DHCPV4_MSG_RELEASE && a) {
a->flags &= ~OAF_BOUND;
if (!(a->flags & OAF_STATIC))
a->valid_until = now - 1;
} else if (msg == DHCPV4_MSG_DECLINE && a) {
a->flags &= ~OAF_BOUND;
if (!(a->flags & OAF_STATIC)) {
memset(a->hwaddr, 0, sizeof(a->hwaddr));
a->valid_until = now + 3600; /* Block address for 1h */
}
}
dhcpv6_write_statefile();
return lease;
}
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