#include <sys/timerfd.h>
#include <arpa/inet.h>
+#include <libubox/md5.h>
+
#include "odhcpd.h"
#include "dhcpv4.h"
#include "dhcpv6.h"
+static void dhcpv4_netevent_cb(unsigned long event, struct netevent_handler_info *info);
+static int setup_dhcpv4_addresses(struct interface *iface);
+static void update_static_assignments(struct interface *iface);
+static void valid_until_cb(struct uloop_timeout *event);
+static void handle_addrlist_change(struct interface *iface);
static void free_dhcpv4_assignment(struct dhcpv4_assignment *a);
+static void dhcpv4_fr_start(struct dhcpv4_assignment *a);
+static void dhcpv4_fr_stop(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);
+ enum dhcpv4_msg msg, const uint8_t *mac, const uint32_t reqaddr,
+ uint32_t *leasetime, const char *hostname, const size_t hostname_len,
+ const bool accept_fr_nonce, bool *incl_fr_opt, uint32_t *fr_serverid);
+
+static struct netevent_handler dhcpv4_netevent_handler = { .cb = dhcpv4_netevent_cb, };
+static struct uloop_timeout valid_until_timeout = {.cb = valid_until_cb};
+static uint32_t serial = 0;
+
+struct odhcpd_ref_ip {
+ struct list_head head;
+ int ref_cnt;
+ struct odhcpd_ipaddr addr;
+};
/* Create socket and register events */
-int init_dhcpv4(void)
+int dhcpv4_init(void)
{
+ uloop_timeout_set(&valid_until_timeout, 1000);
+ netlink_add_netevent_handler(&dhcpv4_netevent_handler);
+
return 0;
}
-int setup_dhcpv4_interface(struct interface *iface, bool enable)
+int dhcpv4_setup_interface(struct interface *iface, bool enable)
{
+ int ret = 0;
+
if (iface->dhcpv4_event.uloop.fd > 0) {
uloop_fd_delete(&iface->dhcpv4_event.uloop);
close(iface->dhcpv4_event.uloop.fd);
}
if (iface->dhcpv4 && enable) {
+ struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT),
+ {INADDR_ANY}, {0}};
+ int val = 1;
+
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;
+ if (!iface->dhcpv4_fr_ips.next)
+ INIT_LIST_HEAD(&iface->dhcpv4_fr_ips);
+
+ iface->dhcpv4_event.uloop.fd = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
+ if (iface->dhcpv4_event.uloop.fd < 0) {
+ syslog(LOG_ERR, "socket(AF_INET): %m");
+ ret = -1;
+ goto out;
}
/* 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));
+ if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_REUSEADDR,
+ &val, sizeof(val)) < 0) {
+ syslog(LOG_ERR, "setsockopt(SO_REUSEADDR): %m");
+ ret = -1;
+ goto out;
+ }
+
+ if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_BROADCAST,
+ &val, sizeof(val)) < 0) {
+ syslog(LOG_ERR, "setsockopt(SO_BROADCAST): %m");
+ ret = -1;
+ goto out;
+ }
+
+ if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_PKTINFO,
+ &val, sizeof(val)) < 0) {
+ syslog(LOG_ERR, "setsockopt(IP_PKTINFO): %m");
+ ret = -1;
+ goto out;
+ }
val = IPTOS_PREC_INTERNETCONTROL;
- setsockopt(sock, IPPROTO_IP, IP_TOS, &val, sizeof(val));
+ if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_TOS,
+ &val, sizeof(val)) < 0) {
+ syslog(LOG_ERR, "setsockopt(IP_TOS): %m");
+ ret = -1;
+ goto out;
+ }
val = IP_PMTUDISC_DONT;
- setsockopt(sock, IPPROTO_IP, IP_MTU_DISCOVER, &val, sizeof(val));
+ if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_MTU_DISCOVER,
+ &val, sizeof(val)) < 0) {
+ syslog(LOG_ERR, "setsockopt(IP_MTU_DISCOVER): %m");
+ ret = -1;
+ goto out;
+ }
- setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE,
- iface->ifname, strlen(iface->ifname));
+ if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_BINDTODEVICE,
+ iface->ifname, strlen(iface->ifname)) < 0) {
+ syslog(LOG_ERR, "setsockopt(SO_BINDTODEVICE): %m");
+ ret = -1;
+ goto out;
+ }
- struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT),
- {INADDR_ANY}, {0}};
+ if (bind(iface->dhcpv4_event.uloop.fd, (struct sockaddr*)&bind_addr,
+ sizeof(bind_addr)) < 0) {
+ syslog(LOG_ERR, "bind(): %m");
+ ret = -1;
+ goto out;
+ }
- 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 (setup_dhcpv4_addresses(iface) < 0) {
+ ret = -1;
+ goto out;
}
+ iface->dhcpv4_event.handle_dgram = handle_dhcpv4;
+ odhcpd_register(&iface->dhcpv4_event);
+
+ update_static_assignments(iface);
+ } 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));
+ }
+
+out:
+ if (ret < 0 && iface->dhcpv4_event.uloop.fd > 0) {
+ close(iface->dhcpv4_event.uloop.fd);
+ iface->dhcpv4_event.uloop.fd = -1;
+ }
+
+ return ret;
+}
+
+
+static void dhcpv4_netevent_cb(unsigned long event, struct netevent_handler_info *info)
+{
+ struct interface *iface = info->iface;
+
+ if (!iface || iface->dhcpv4 == MODE_DISABLED)
+ return;
+
+ switch (event) {
+ case NETEV_IFINDEX_CHANGE:
+ dhcpv4_setup_interface(iface, true);
+ break;
+ case NETEV_ADDRLIST_CHANGE:
+ handle_addrlist_change(iface);
+ break;
+ default:
+ break;
+ }
+}
+
+static struct dhcpv4_assignment *find_assignment_by_hwaddr(struct interface *iface, const uint8_t *hwaddr)
+{
+ struct dhcpv4_assignment *a;
+
+ list_for_each_entry(a, &iface->dhcpv4_assignments, head)
+ if (!memcmp(a->hwaddr, hwaddr, 6))
+ return a;
+
+ return NULL;
+}
+
+static struct dhcpv4_assignment *find_assignment_by_addr(struct interface *iface, const uint32_t addr)
+{
+ struct dhcpv4_assignment *a;
+
+ list_for_each_entry(a, &iface->dhcpv4_assignments, head)
+ if (a->addr == addr)
+ return a;
+
+ return NULL;
+}
- if (ntohl(iface->dhcpv4_start.s_addr) > ntohl(iface->dhcpv4_end.s_addr)) {
- syslog(LOG_ERR, "Invalid DHCP range");
- return -1;
+static int setup_dhcpv4_addresses(struct interface *iface)
+{
+ iface->dhcpv4_start_ip.s_addr = INADDR_ANY;
+ iface->dhcpv4_end_ip.s_addr = INADDR_ANY;
+ iface->dhcpv4_local.s_addr = INADDR_ANY;
+ iface->dhcpv4_bcast.s_addr = INADDR_ANY;
+ iface->dhcpv4_mask.s_addr = INADDR_ANY;
+
+ /* Sanity checks */
+ if (iface->dhcpv4_start.s_addr & htonl(0xffff0000) ||
+ iface->dhcpv4_end.s_addr & htonl(0xffff0000) ||
+ ntohl(iface->dhcpv4_start.s_addr) > ntohl(iface->dhcpv4_end.s_addr)) {
+ syslog(LOG_ERR, "invalid DHCP range for %s", iface->name);
+ return -1;
+ }
+
+ if (!iface->addr4_len) {
+ syslog(LOG_WARNING, "no network(s) available on %s", iface->name);
+ return -1;
+ }
+
+ uint32_t start = ntohl(iface->dhcpv4_start.s_addr);
+ uint32_t end = ntohl(iface->dhcpv4_end.s_addr);
+
+ for (size_t i = 0; i < iface->addr4_len && start && end; i++) {
+ struct in_addr *addr = &iface->addr4[i].addr.in;
+ struct in_addr mask;
+
+ odhcpd_bitlen2netmask(false, iface->addr4[i].prefix, &mask);
+ if ((start & ntohl(~mask.s_addr)) == start &&
+ (end & ntohl(~mask.s_addr)) == end) {
+ iface->dhcpv4_start_ip.s_addr = htonl(start) |
+ (addr->s_addr & mask.s_addr);
+ iface->dhcpv4_end_ip.s_addr = htonl(end) |
+ (addr->s_addr & mask.s_addr);
+ iface->dhcpv4_local = *addr;
+ iface->dhcpv4_bcast = iface->addr4[i].broadcast;
+ iface->dhcpv4_mask = mask;
+ return 0;
}
+ }
- uint32_t mask = iface->addr4[0].prefix ? htonl(~((1 << (32 - iface->addr4[0].prefix)) - 1)) : 0;
-
- /* Create a range if not specified */
- if (!(iface->dhcpv4_start.s_addr & htonl(0xffff0000)) &&
- !(iface->dhcpv4_end.s_addr & htonl(0xffff0000)) &&
- iface->addr4_len) {
- struct in_addr *addr = &iface->addr4[0].addr.in;
-
- 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) &&
- (start & ntohl(~mask)) == start &&
- (end & ntohl(~mask)) == end) {
- iface->dhcpv4_start.s_addr = htonl(start) |
- (addr->s_addr & mask);
- iface->dhcpv4_end.s_addr = htonl(end) |
- (addr->s_addr & mask);
- } else if (ntohl(mask) <= 0xfffffff0) {
- start = addr->s_addr & mask;
- end = addr->s_addr & mask;
-
- if (ntohl(mask) <= 0xffffff00) {
- iface->dhcpv4_start.s_addr = start | htonl(100);
- iface->dhcpv4_end.s_addr = end | htonl(250);
- } else if (ntohl(mask) <= 0xffffffc0) {
- iface->dhcpv4_start.s_addr = start | htonl(10);
- iface->dhcpv4_end.s_addr = end | htonl(60);
- } else if (ntohl(mask) <= 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);
- }
- }
+ /* Don't allocate IP range for subnets bigger than 28 */
+ if (iface->addr4[0].prefix > 28) {
+ syslog(LOG_WARNING, "auto allocation of DHCP range fails on %s", iface->name);
+ return -1;
+ }
+
+ iface->dhcpv4_local = iface->addr4[0].addr.in;
+ iface->dhcpv4_bcast = iface->addr4[0].broadcast;
+ odhcpd_bitlen2netmask(false, iface->addr4[0].prefix, &iface->dhcpv4_mask);
+ end = start = iface->dhcpv4_local.s_addr & iface->dhcpv4_mask.s_addr;
+
+ /* Auto allocate ranges */
+ if (ntohl(iface->dhcpv4_mask.s_addr) <= 0xffffff00) {
+ iface->dhcpv4_start_ip.s_addr = start | htonl(100);
+ iface->dhcpv4_end_ip.s_addr = end | htonl(250);
+ } else if (ntohl(iface->dhcpv4_mask.s_addr) <= 0xffffffc0) {
+ iface->dhcpv4_start_ip.s_addr = start | htonl(10);
+ iface->dhcpv4_end_ip.s_addr = end | htonl(60);
+ } else if (ntohl(iface->dhcpv4_mask.s_addr) <= 0xffffffe0) {
+ iface->dhcpv4_start_ip.s_addr = start | htonl(10);
+ iface->dhcpv4_end_ip.s_addr = end | htonl(30);
+ } else {
+ iface->dhcpv4_start_ip.s_addr = start | htonl(3);
+ iface->dhcpv4_end_ip.s_addr = end | htonl(12);
+ }
+
+ return 0;
+}
+
+static void update_static_assignments(struct interface *iface)
+{
+ struct dhcpv4_assignment *a, *c;
+
+ /* Cleanup static entries not belonging to the network */
+ list_for_each_entry_safe(a, c, &iface->dhcpv4_assignments, head) {
+ if ((a->flags & OAF_STATIC) &&
+ ((a->addr & iface->dhcpv4_mask.s_addr) !=
+ (iface->dhcpv4_start.s_addr & iface->dhcpv4_mask.s_addr)))
+ free_dhcpv4_assignment(a);
+ }
+
+ /* Parse static entries */
+ struct lease *lease;
+ list_for_each_entry(lease, &leases, head) {
+ if ((iface->dhcpv4_start_ip.s_addr & iface->dhcpv4_mask.s_addr) !=
+ (lease->ipaddr.s_addr & iface->dhcpv4_mask.s_addr)) {
+ continue;
}
- /* Parse static entries */
- struct lease *lease;
- list_for_each_entry(lease, &leases, head) {
+ a = find_assignment_by_hwaddr(iface, lease->mac.ether_addr_octet);
+
+ if (!a) {
+ /* Check if there's an assignment with the specified IP address */
+ if (find_assignment_by_addr(iface, lease->ipaddr.s_addr))
+ continue;
+
/* Construct entry */
- struct dhcpv4_assignment *a = calloc(1, sizeof(*a));
+ a = calloc(1, sizeof(*a));
if (!a) {
syslog(LOG_ERR, "Calloc failed for static lease on interface %s",
iface->ifname);
- return -1;
+ continue;
}
+ memcpy(a->hwaddr, lease->mac.ether_addr_octet, sizeof(a->hwaddr));
+ }
- a->leasetime = lease->dhcpv4_leasetime;
+ a->leasetime = lease->dhcpv4_leasetime;
+
+ a->addr = lease->ipaddr.s_addr;
+ /* Static assignment */
+ a->flags |= OAF_STATIC;
+ /* Infinite valid */
+ a->valid_until = 0;
+ a->iface = iface;
+ if (lease->hostname[0]) {
+ free(a->hostname);
+ a->hostname = strdup(lease->hostname);
+ }
- 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;
+ /* Assign to all interfaces */
+ list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
+ if (ntohl(c->addr) > ntohl(a->addr)) {
+ list_add_tail(&a->head, &c->head);
+ break;
}
+ }
- if (&c->head == &iface->dhcpv4_assignments)
- list_add(&a->head, &iface->dhcpv4_assignments);
+ 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);
+static void inc_ref_cnt_ip(struct odhcpd_ref_ip **ptr, struct odhcpd_ref_ip *ip)
+{
+ *ptr = ip;
+ ip->ref_cnt++;
+}
+
+static void decr_ref_cnt_ip(struct odhcpd_ref_ip **ptr, struct interface *iface)
+{
+ struct odhcpd_ref_ip *ip = *ptr;
+
+ if (--ip->ref_cnt == 0) {
+ netlink_setup_addr(&ip->addr, iface->ifindex, false, false);
+
+ list_del(&ip->head);
+ free(ip);
+ }
+
+ *ptr = NULL;
+}
+
+static bool leases_require_fr(struct interface *iface, struct odhcpd_ipaddr *addr,
+ uint32_t mask)
+{
+ struct dhcpv4_assignment *a = NULL;
+ struct odhcpd_ref_ip *fr_ip = NULL;
+
+ list_for_each_entry(a, &iface->dhcpv4_assignments, head) {
+ if ((a->accept_fr_nonce || iface->dhcpv4_forcereconf) &&
+ !a->fr_ip &&
+ ((a->addr & mask) == (addr->addr.in.s_addr & mask))) {
+ if (!fr_ip) {
+ fr_ip = calloc(1, sizeof(*fr_ip));
+ if (!fr_ip)
+ break;
+
+ list_add(&fr_ip->head, &iface->dhcpv4_fr_ips);
+ fr_ip->addr = *addr;
+ }
+ inc_ref_cnt_ip(&a->fr_ip, fr_ip);
}
+ }
+
+ return fr_ip ? true : false;
+}
+
+static void valid_until_cb(struct uloop_timeout *event)
+{
+ time_t now = odhcpd_time();
+ struct interface *iface;
+ list_for_each_entry(iface, &interfaces, head) {
+ if (iface->dhcpv4 != MODE_SERVER || iface->dhcpv4_assignments.next == NULL)
+ continue;
- // Clean invalid assignments
struct dhcpv4_assignment *a, *n;
list_for_each_entry_safe(a, n, &iface->dhcpv4_assignments, head) {
- if ((htonl(a->addr) & mask) !=
- (iface->dhcpv4_start.s_addr & mask))
+ if (!INFINITE_VALID(a->valid_until) && a->valid_until < now)
free_dhcpv4_assignment(a);
}
+ }
+ uloop_timeout_set(event, 1000);
+}
- 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));
+static void handle_addrlist_change(struct interface *iface)
+{
+ struct odhcpd_ipaddr ip;
+ struct odhcpd_ref_ip *a;
+ struct dhcpv4_assignment *c;
+ uint32_t mask = iface->dhcpv4_mask.s_addr;
+
+ memset(&ip, 0, sizeof(ip));
+ ip.addr.in = iface->dhcpv4_local;
+ ip.prefix = odhcpd_netmask2bitlen(false, &iface->dhcpv4_mask);
+ ip.broadcast = iface->dhcpv4_bcast;
+
+ setup_dhcpv4_addresses(iface);
+
+ if ((ip.addr.in.s_addr & mask) ==
+ (iface->dhcpv4_local.s_addr & iface->dhcpv4_mask.s_addr))
+ return;
+
+ if (ip.addr.in.s_addr && !leases_require_fr(iface, &ip, mask))
+ return;
+
+ if (iface->dhcpv4_local.s_addr == INADDR_ANY || list_empty(&iface->dhcpv4_fr_ips))
+ return;
+
+ a = list_first_entry(&iface->dhcpv4_fr_ips, struct odhcpd_ref_ip, head);
+
+ if (netlink_setup_addr(&a->addr, iface->ifindex, false, true)) {
+ syslog(LOG_ERR, "Failed to add ip address");
+ return;
+ }
+
+ list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
+ if ((c->flags & OAF_BOUND) && c->fr_ip && !c->fr_cnt) {
+ if (c->accept_fr_nonce || iface->dhcpv4_forcereconf)
+ dhcpv4_fr_start(c);
+ else
+ dhcpv4_fr_stop(c);
+ }
}
- return 0;
}
static char *dhcpv4_msg_to_string(uint8_t reqmsg)
return "DHCPV4_MSG_RELEASE";
case (DHCPV4_MSG_INFORM):
return "DHCPV4_MSG_INFORM";
+ case (DHCPV4_MSG_FORCERENEW):
+ return "DHCPV4_MSG_FORCERENEW";
default:
return "UNKNOWN";
}
if (a->head.next)
list_del(&a->head);
+ if (a->fr_ip)
+ dhcpv4_fr_stop(a);
+
free(a->hostname);
free(a);
}
uint8_t type, uint8_t len, const void *data)
{
uint8_t *c = *cookie;
- if (*cookie + 2 + len > (uint8_t*)&msg[1])
+ uint8_t *end = (uint8_t *)msg + sizeof(*msg);
+
+ if (*cookie + 2 + len > end)
return;
*c++ = type;
*cookie = c + len;
}
+static void dhcpv4_fr_send(struct dhcpv4_assignment *a)
+{
+ struct dhcpv4_message fr_msg = {
+ .op = DHCPV4_BOOTREPLY,
+ .htype = 1,
+ .hlen = 6,
+ .hops = 0,
+ .secs = 0,
+ .flags = 0,
+ .ciaddr = {INADDR_ANY},
+ .yiaddr = {INADDR_ANY},
+ .siaddr = {INADDR_ANY},
+ .giaddr = {INADDR_ANY},
+ .chaddr = {0},
+ .sname = {0},
+ .file = {0},
+ };
+ struct dhcpv4_auth_forcerenew *auth_o, auth = {
+ .protocol = 3,
+ .algorithm = 1,
+ .rdm = 0,
+ .replay = {htonl(time(NULL)), htonl(++serial)},
+ .type = 2,
+ .key = {0},
+ };
+ struct interface *iface = a->iface;
+
+ odhcpd_urandom(&fr_msg.xid, sizeof(fr_msg.xid));
+ memcpy(fr_msg.chaddr, a->hwaddr, fr_msg.hlen);
+
+ fr_msg.options[0] = 0x63;
+ fr_msg.options[1] = 0x82;
+ fr_msg.options[2] = 0x53;
+ fr_msg.options[3] = 0x63;
+
+ uint8_t *cookie = &fr_msg.options[4];
+ uint8_t msg = DHCPV4_MSG_FORCERENEW;
+
+ dhcpv4_put(&fr_msg, &cookie, DHCPV4_OPT_MESSAGE, 1, &msg);
+ if (a->accept_fr_nonce) {
+ dhcpv4_put(&fr_msg, &cookie, DHCPV4_OPT_AUTHENTICATION, sizeof(auth), &auth);
+ auth_o = (struct dhcpv4_auth_forcerenew *)(cookie - sizeof(auth));
+ dhcpv4_put(&fr_msg, &cookie, DHCPV4_OPT_END, 0, NULL);
+
+ md5_ctx_t md5;
+ uint8_t secretbytes[64];
+ memset(secretbytes, 0, sizeof(secretbytes));
+ memcpy(secretbytes, a->key, sizeof(a->key));
+
+ for (size_t i = 0; i < sizeof(secretbytes); ++i)
+ secretbytes[i] ^= 0x36;
+
+ md5_begin(&md5);
+ md5_hash(secretbytes, sizeof(secretbytes), &md5);
+ md5_hash(&fr_msg, sizeof(fr_msg), &md5);
+ md5_end(auth_o->key, &md5);
+
+ for (size_t i = 0; i < sizeof(secretbytes); ++i) {
+ secretbytes[i] ^= 0x36;
+ secretbytes[i] ^= 0x5c;
+ }
+
+ md5_begin(&md5);
+ md5_hash(secretbytes, sizeof(secretbytes), &md5);
+ md5_hash(auth_o->key, sizeof(auth_o->key), &md5);
+ md5_end(auth_o->key, &md5);
+ } else {
+ dhcpv4_put(&fr_msg, &cookie, DHCPV4_OPT_SERVERID, 4,
+ &a->fr_ip->addr.addr.in.s_addr);
+ dhcpv4_put(&fr_msg, &cookie, DHCPV4_OPT_END, 0, NULL);
+ }
+
+ struct sockaddr_in dest;
+ memset(&dest, 0, sizeof(dest));
+ dest.sin_family = AF_INET;
+ dest.sin_port = htons(DHCPV4_CLIENT_PORT);
+ dest.sin_addr.s_addr = a->addr;
+
+ syslog(LOG_WARNING, "sending %s to %02x:%02x:%02x:%02x:%02x:%02x - %s",
+ dhcpv4_msg_to_string(msg),
+ a->hwaddr[0], a->hwaddr[1], a->hwaddr[2],
+ a->hwaddr[3], a->hwaddr[4], a->hwaddr[5],
+ inet_ntoa(dest.sin_addr));
+
+ sendto(iface->dhcpv4_event.uloop.fd, &fr_msg, sizeof(fr_msg),
+ MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest));
+}
+
+static void dhcpv4_fr_timer(struct uloop_timeout *event)
+{
+ struct dhcpv4_assignment *a = container_of(event, struct dhcpv4_assignment, fr_timer);
+
+ if (a->fr_cnt > 0 && a->fr_cnt < 8) {
+ dhcpv4_fr_send(a);
+ uloop_timeout_set(&a->fr_timer, 1000 << a->fr_cnt);
+ a->fr_cnt++;
+ } else
+ dhcpv4_fr_stop(a);
+}
+
+static void dhcpv4_fr_start(struct dhcpv4_assignment *a)
+{
+ uloop_timeout_set(&a->fr_timer, 1000 << a->fr_cnt);
+ a->fr_timer.cb = dhcpv4_fr_timer;
+ a->fr_cnt++;
+
+ dhcpv4_fr_send(a);
+}
+
+static void dhcpv4_fr_stop(struct dhcpv4_assignment *a)
+{
+ uloop_timeout_cancel(&a->fr_timer);
+ decr_ref_cnt_ip(&a->fr_ip, a->iface);
+ a->fr_cnt = 0;
+ a->fr_timer.cb = NULL;
+}
+
// Handler for DHCPv4 messages
static void handle_dhcpv4(void *addr, void *data, size_t len,
struct interface *iface, _unused void *dest_addr)
syslog(LOG_NOTICE, "Got DHCPv4 request");
- if (!iface->addr4_len) {
- syslog(LOG_WARNING, "DHCPv4 no address found on %s", iface->name);
+ if (!iface->dhcpv4_start_ip.s_addr && !iface->dhcpv4_end_ip.s_addr) {
+ syslog(LOG_WARNING, "No DHCP range available on %s", iface->name);
return;
}
- struct in_addr *ifaddr = &iface->addr4[0].addr.in;
- struct in_addr *ifbroadcast = &iface->addr4[0].broadcast;
- uint32_t mask = iface->addr4[0].prefix ? htonl(~((1 << (32 - iface->addr4[0].prefix)) - 1)) : 0;
- uint32_t network = iface->addr4[0].addr.in.s_addr & mask;
int sock = iface->dhcpv4_event.uloop.fd;
- if ((iface->dhcpv4_start.s_addr & mask) != network ||
- (iface->dhcpv4_end.s_addr & mask) != network) {
- syslog(LOG_WARNING, "DHCPv4 range out of assigned network");
- return;
- }
-
struct dhcpv4_message reply = {
.op = DHCPV4_BOOTREPLY,
- .htype = 1,
- .hlen = 6,
+ .htype = req->htype,
+ .hlen = req->hlen,
.hops = 0,
.xid = req->xid,
.secs = 0,
.flags = req->flags,
.ciaddr = {INADDR_ANY},
.giaddr = req->giaddr,
- .siaddr = *ifaddr,
+ .siaddr = iface->dhcpv4_local,
};
memcpy(reply.chaddr, req->chaddr, sizeof(reply.chaddr));
uint8_t reqmsg = DHCPV4_MSG_REQUEST;
uint8_t msg = DHCPV4_MSG_ACK;
- struct in_addr reqaddr = {INADDR_ANY};
+ uint32_t reqaddr = INADDR_ANY;
uint32_t leasetime = 0;
size_t hostname_len = 0;
char hostname[256];
+ bool accept_fr_nonce = false;
+ bool incl_fr_opt = false;
uint8_t *start = &req->options[4];
uint8_t *end = ((uint8_t*)data) + len;
} 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, 4))
+ if (memcmp(opt->data, &iface->dhcpv4_local, 4))
return;
} else if (iface->filter_class && opt->type == DHCPV4_OPT_USER_CLASS) {
uint8_t *c = opt->data, *cend = &opt->data[opt->len];
}
} else if (opt->type == DHCPV4_OPT_LEASETIME && opt->len == 4)
memcpy(&leasetime, opt->data, 4);
+ else if (opt->type == DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE && opt->len > 0) {
+ for (uint8_t i = 0; i < opt->len; i++) {
+ if (opt->data[i] == 1) {
+ accept_fr_nonce = true;
+ break;
+ }
+ }
+
+ }
}
if (reqmsg != DHCPV4_MSG_DISCOVER && reqmsg != DHCPV4_MSG_REQUEST &&
return;
struct dhcpv4_assignment *lease = NULL;
+ uint32_t serverid = iface->dhcpv4_local.s_addr;
+ uint32_t fr_serverid = INADDR_ANY;
+
if (reqmsg != DHCPV4_MSG_INFORM)
lease = dhcpv4_lease(iface, reqmsg, req->chaddr, reqaddr,
- &leasetime, hostname, hostname_len);
+ &leasetime, hostname, hostname_len,
+ accept_fr_nonce, &incl_fr_opt, &fr_serverid);
if (!lease) {
if (reqmsg == DHCPV4_MSG_REQUEST)
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)) {
+ else if (reqmsg == DHCPV4_MSG_REQUEST &&
+ ((reqaddr && reqaddr != lease->addr) ||
+ (req->ciaddr.s_addr && req->ciaddr.s_addr != 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.
+ * client changed the network or the network has been changed. 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.
*
*/
+
+ /*
+ *
+ * Buggy clients do serverid checking in nack messages; therefore set the
+ * serverid in nack messages triggered by a previous force renew equal to
+ * the server id in use at that time by the server
+ *
+ */
+ if (fr_serverid)
+ serverid = fr_serverid;
+
+ if (req->ciaddr.s_addr &&
+ ((iface->dhcpv4_start_ip.s_addr & iface->dhcpv4_mask.s_addr) !=
+ (req->ciaddr.s_addr & iface->dhcpv4_mask.s_addr)))
+ req->ciaddr.s_addr = INADDR_ANY;
}
syslog(LOG_WARNING, "received %s from %02x:%02x:%02x:%02x:%02x:%02x",
req->chaddr[0],req->chaddr[1],req->chaddr[2],
req->chaddr[3],req->chaddr[4],req->chaddr[5]);
+#ifdef WITH_UBUS
+ if (reqmsg == DHCPV4_MSG_RELEASE)
+ ubus_bcast_dhcp_event("dhcp.release", req->chaddr, req->hlen,
+ &req->ciaddr, hostname, iface->ifname);
+#endif
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);
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_SERVERID, 4, &serverid);
if (lease) {
uint32_t val;
- reply.yiaddr.s_addr = htonl(lease->addr);
+ reply.yiaddr.s_addr = lease->addr;
val = htonl(leasetime);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_LEASETIME, 4, &val);
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_REBIND, 4, &val);
}
- dhcpv4_put(&reply, &cookie, DHCPV4_OPT_NETMASK, 4, &mask);
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_NETMASK, 4,
+ &iface->dhcpv4_mask.s_addr);
if (lease->hostname)
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_HOSTNAME,
strlen(lease->hostname), lease->hostname);
- if (ifbroadcast->s_addr != INADDR_ANY)
- dhcpv4_put(&reply, &cookie, DHCPV4_OPT_BROADCAST, 4, ifbroadcast);
+ if (iface->dhcpv4_bcast.s_addr != INADDR_ANY)
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_BROADCAST, 4, &iface->dhcpv4_bcast);
+
+ if (incl_fr_opt) {
+ if (reqmsg == DHCPV4_MSG_REQUEST) {
+ struct dhcpv4_auth_forcerenew auth = {
+ .protocol = 3,
+ .algorithm = 1,
+ .rdm = 0,
+ .replay = {htonl(time(NULL)), htonl(++serial)},
+ .type = 1,
+ .key = {0},
+ };
+
+ memcpy(auth.key, lease->key, sizeof(auth.key));
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_AUTHENTICATION, sizeof(auth), &auth);
+ } else {
+ uint8_t one = 1;
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE,
+ sizeof(one), &one);
+ }
+ }
}
- struct ifreq ifr = {.ifr_name = ""};
- strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name));
+ struct ifreq ifr;
+
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name) - 1);
if (!ioctl(sock, SIOCGIFMTU, &ifr)) {
uint16_t mtu = htons(ifr.ifr_mtu);
}
if (iface->dhcpv4_router_cnt == 0)
- dhcpv4_put(&reply, &cookie, DHCPV4_OPT_ROUTER, 4, ifaddr);
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_ROUTER, 4, &iface->dhcpv4_local);
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);
+ dhcpv4_put(&reply, &cookie, DHCPV4_OPT_DNSSERVER, 4, &iface->dhcpv4_local);
else
dhcpv4_put(&reply, &cookie, DHCPV4_OPT_DNSSERVER,
4 * iface->dhcpv4_dns_cnt, iface->dhcpv4_dns);
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;
+#ifdef WITH_UBUS
+ if (msg == DHCPV4_MSG_ACK)
+ ubus_bcast_dhcp_event("dhcp.ack", req->chaddr, req->hlen, &reply.yiaddr,
+ hostname, iface->ifname);
+#endif
}
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 start = ntohl(iface->dhcpv4_start_ip.s_addr);
+ uint32_t end = ntohl(iface->dhcpv4_end_ip.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)) {
+ if (start <= ntohl(raddr) && ntohl(raddr) <= end &&
+ !find_assignment_by_addr(iface, raddr)) {
assign->addr = raddr;
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));
+ ((uint8_t *)&assign->addr)[0],
+ ((uint8_t *)&assign->addr)[1],
+ ((uint8_t *)&assign->addr)[2],
+ ((uint8_t *)&assign->addr)[3]);
return true;
}
uint32_t try = (((uint32_t)rand()) % count) + start;
if (list_empty(&iface->dhcpv4_assignments)) {
- assign->addr = try;
+ assign->addr = htonl(try);
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));
+ ((uint8_t *)&assign->addr)[0],
+ ((uint8_t *)&assign->addr)[1],
+ ((uint8_t *)&assign->addr)[2],
+ ((uint8_t *)&assign->addr)[3]);
return true;
}
for (uint32_t i = 0; i < count; ++i) {
- if (dhcpv4_test(iface, try)) {
+ if (!find_assignment_by_addr(iface, htonl(try))) {
/* test was successful: IP address is not assigned, assign it */
- assign->addr = try;
+ assign->addr = htonl(try);
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);
+ ((uint8_t *)&assign->addr)[0],
+ ((uint8_t *)&assign->addr)[1],
+ ((uint8_t *)&assign->addr)[2],
+ ((uint8_t *)&assign->addr)[3],
+ i, count);
return true;
}
try = (((try - start) + 1) % count) + start;
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)
+ enum dhcpv4_msg msg, const uint8_t *mac, const uint32_t reqaddr,
+ uint32_t *leasetime, const char *hostname, const size_t hostname_len,
+ const bool accept_fr_nonce, bool *incl_fr_opt, uint32_t *fr_serverid)
{
+ struct dhcpv4_assignment *a = find_assignment_by_hwaddr(iface, mac);
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 (a && (a->flags & OAF_BOUND) && a->fr_ip) {
+ *fr_serverid = a->fr_ip->addr.addr.in.s_addr;
+ dhcpv4_fr_stop(a);
}
if (msg == DHCPV4_MSG_DISCOVER || msg == DHCPV4_MSG_REQUEST) {
bool assigned = !!a;
- 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;
+ if (!a) {
+ if (!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, reqaddr);
+ if (assigned) {
+ a->iface = iface;
+ list_add(&a->head, &iface->dhcpv4_assignments);
+ }
}
- memcpy(a->hwaddr, mac, sizeof(a->hwaddr));
- /* Don't consider new assignment as infinite */
- a->valid_until = now;
+ } else if ((a->addr & iface->dhcpv4_mask.s_addr) !=
+ (iface->dhcpv4_start_ip.s_addr & iface->dhcpv4_mask.s_addr)) {
+ list_del(&a->head);
- assigned = dhcpv4_assign(iface, a, raddr);
+ assigned = dhcpv4_assign(iface, a, reqaddr);
if (assigned)
list_add(&a->head, &iface->dhcpv4_assignments);
}
if (msg == DHCPV4_MSG_DISCOVER) {
a->flags &= ~OAF_BOUND;
+ *incl_fr_opt = accept_fr_nonce;
if (!(a->flags & OAF_STATIC))
a->valid_until = now;
} else {
}
}
- a->flags |= OAF_BOUND;
+ if (!(a->flags & OAF_BOUND)) {
+ a->accept_fr_nonce = accept_fr_nonce;
+ *incl_fr_opt = accept_fr_nonce;
+ odhcpd_urandom(a->key, sizeof(a->key));
+ a->flags |= OAF_BOUND;
+ } else
+ *incl_fr_opt = false;
if (!(a->flags & OAF_STATIC))
a->valid_until = ((*leasetime == UINT32_MAX) ? 0 : (time_t)(now + *leasetime));
projects / project / odhcpd.git / blobdiff