X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fdhcpv4.c;h=2634f65a69e997c5292c7c7f3679709c45cf62d4;hb=c0c8034bc17519c7960f40f6d796b5485cfc4cdb;hp=a657e13d325f9e4de34a8ec0e5c904d44967274d;hpb=b564819c4856b666e0a7d40b6f25ba84c120bcd7;p=oweals%2Fodhcpd.git diff --git a/src/dhcpv4.c b/src/dhcpv4.c index a657e13..2634f65 100644 --- a/src/dhcpv4.c +++ b/src/dhcpv4.c @@ -1,5 +1,6 @@ /** * Copyright (C) 2012-2013 Steven Barth + * Copyright (C) 2016 Hans Dedecker * * 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 @@ -28,24 +29,373 @@ #include #include +#include + #include "odhcpd.h" #include "dhcpv4.h" #include "dhcpv6.h" - +#define PACKET_SIZE(start, end) (((uint8_t *)end - (uint8_t *)start) < DHCPV4_MIN_PACKET_SIZE ? \ + DHCPV4_MIN_PACKET_SIZE : (uint8_t *)end - (uint8_t *)start) + +static void dhcpv4_netevent_cb(unsigned long event, struct netevent_handler_info *info); +static int setup_dhcpv4_addresses(struct interface *iface); +static bool addr_is_fr_ip(struct interface *iface, struct in_addr *addr); +static void valid_until_cb(struct uloop_timeout *event); +static void handle_addrlist_change(struct interface *iface); +static void dhcpv4_fr_start(struct dhcp_assignment *a); +static void dhcpv4_fr_rand_delay(struct dhcp_assignment *a); +static void dhcpv4_fr_stop(struct dhcp_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, - const char *hostname); +static struct dhcp_assignment* dhcpv4_lease(struct interface *iface, + 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, + const char *reqopts, const size_t reqopts_len); + +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 dhcpv4_init(void) +{ + uloop_timeout_set(&valid_until_timeout, 1000); + netlink_add_netevent_handler(&dhcpv4_netevent_handler); + + return 0; +} + +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); + iface->dhcpv4_event.uloop.fd = -1; + } + + if (iface->dhcpv4 && enable) { + struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT), + {INADDR_ANY}, {0}}; + int val = 1; + + 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 */ + 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; + 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; + 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; + } + + 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; + } + + 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 (setup_dhcpv4_addresses(iface) < 0) { + ret = -1; + goto out; + } + + iface->dhcpv4_event.handle_dgram = handle_dhcpv4; + odhcpd_register(&iface->dhcpv4_event); + } else { + while (!list_empty(&iface->dhcpv4_assignments)) + free_assignment(list_first_entry(&iface->dhcpv4_assignments, + struct dhcp_assignment, head)); + } + +out: + if (ret < 0 && iface->dhcpv4_event.uloop.fd >= 0) { + close(iface->dhcpv4_event.uloop.fd); + iface->dhcpv4_event.uloop.fd = -1; + } -// Create socket and register events -int init_dhcpv4(void) + 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 dhcp_assignment *find_assignment_by_hwaddr(struct interface *iface, const uint8_t *hwaddr) +{ + struct dhcp_assignment *a; + + list_for_each_entry(a, &iface->dhcpv4_assignments, head) + if (!memcmp(a->hwaddr, hwaddr, 6)) + return a; + + return NULL; +} + +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_ERR, "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; + + if (addr_is_fr_ip(iface, addr)) + continue; + + odhcpd_bitlen2netmask(false, iface->addr4[i].prefix, &mask); + if ((start & ntohl(~mask.s_addr)) == start && + (end & ntohl(~mask.s_addr)) == end && + end < ntohl(~mask.s_addr)) { /* Exclude broadcast address */ + 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; + } + } + + /* Don't allocate IP range for subnets bigger than 28 */ + if (iface->addr4[0].prefix > 28) { + syslog(LOG_ERR, "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) { /* /24, 150 of 256, [100..249] */ + iface->dhcpv4_start_ip.s_addr = start | htonl(100); + iface->dhcpv4_end_ip.s_addr = end | htonl(100 + 150 - 1); + } else if (ntohl(iface->dhcpv4_mask.s_addr) <= 0xffffff80) { /* /25, 100 of 128, [20..119] */ + iface->dhcpv4_start_ip.s_addr = start | htonl(20); + iface->dhcpv4_end_ip.s_addr = end | htonl(20 + 100 - 1); + } else if (ntohl(iface->dhcpv4_mask.s_addr) <= 0xffffffc0) { /* /26, 50 of 64, [10..59] */ + iface->dhcpv4_start_ip.s_addr = start | htonl(10); + iface->dhcpv4_end_ip.s_addr = end | htonl(10 + 50 - 1); + } else if (ntohl(iface->dhcpv4_mask.s_addr) <= 0xffffffe0) { /* /27, 20 of 32, [10..29] */ + iface->dhcpv4_start_ip.s_addr = start | htonl(10); + iface->dhcpv4_end_ip.s_addr = end | htonl(10 + 20 - 1); + } else { /* /28, 10 of 16, [3..12] */ + iface->dhcpv4_start_ip.s_addr = start | htonl(3); + iface->dhcpv4_end_ip.s_addr = end | htonl(3 + 10 - 1); + } + return 0; } -char *dhcpv4_msg_to_string(uint8_t reqmsg) +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 addr_is_fr_ip(struct interface *iface, struct in_addr *addr) +{ + struct odhcpd_ref_ip *p; + + list_for_each_entry(p, &iface->dhcpv4_fr_ips, head) { + if (addr->s_addr == p->addr.addr.in.s_addr) + return true; + } + + return false; +} + +static bool leases_require_fr(struct interface *iface, struct odhcpd_ipaddr *addr, + uint32_t mask) +{ + struct dhcp_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) +{ + struct interface *iface; + time_t now = odhcpd_time(); + + avl_for_each_element(&interfaces, iface, avl) { + struct dhcp_assignment *a, *n; + + if (iface->dhcpv4 != MODE_SERVER) + continue; + + list_for_each_entry_safe(a, n, &iface->dhcpv4_assignments, head) { + if (!INFINITE_VALID(a->valid_until) && a->valid_until < now) + free_assignment(a); + } + } + uloop_timeout_set(event, 1000); +} + +static void handle_addrlist_change(struct interface *iface) +{ + struct odhcpd_ipaddr ip; + struct odhcpd_ref_ip *a; + struct dhcp_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 on %s", iface->name); + 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_rand_delay(c); + else + dhcpv4_fr_stop(c); + } + } +} + +static char *dhcpv4_msg_to_string(uint8_t reqmsg) { switch (reqmsg) { case (DHCPV4_MSG_DISCOVER): @@ -64,239 +414,211 @@ 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"; } } -int setup_dhcpv4_interface(struct interface *iface, bool enable) +static void dhcpv4_free_assignment(struct dhcp_assignment *a) { - 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 (a->fr_ip) + dhcpv4_fr_stop(a); +} - 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; - } +static void dhcpv4_put(struct dhcpv4_message *msg, uint8_t **cookie, + uint8_t type, uint8_t len, const void *data) +{ + uint8_t *c = *cookie; + uint8_t *end = (uint8_t *)msg + sizeof(*msg); + bool tag_only = type == DHCPV4_OPT_PAD || type == DHCPV4_OPT_END; + int total_len = tag_only ? 1 : 2 + len; - // Basic IPv6 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 (*cookie + total_len > end) + return; - val = IPTOS_PREC_INTERNETCONTROL; - setsockopt(sock, IPPROTO_IP, IP_TOS, &val, sizeof(val)); + *cookie += total_len; + *c++ = type; - val = IP_PMTUDISC_DONT; - setsockopt(sock, IPPROTO_IP, IP_MTU_DISCOVER, &val, sizeof(val)); + if (tag_only) + return; - setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, - iface->ifname, strlen(iface->ifname)); + *c++ = len; + memcpy(c, data, len); +} - struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT), - {INADDR_ANY}, {0}}; +static void dhcpv4_fr_send(struct dhcp_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; - if (bind(sock, (struct sockaddr*)&bind_addr, sizeof(bind_addr))) { - syslog(LOG_ERR, "Failed to open DHCPv4 server socket: %s", - strerror(errno)); - return -1; - } + 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; - if (ntohl(iface->dhcpv4_start.s_addr) > ntohl(iface->dhcpv4_end.s_addr)) { - syslog(LOG_ERR, "Invalid DHCP range"); - return -1; - } + uint8_t *cookie = &fr_msg.options[4]; + uint8_t msg = DHCPV4_MSG_FORCERENEW; - // 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); - } - } + 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; - // Parse static entries - struct lease *lease; - list_for_each_entry(lease, &leases, head) { - // Construct entry - size_t hostlen = strlen(lease->hostname) + 1; - struct dhcpv4_assignment *a = calloc(1, sizeof(*a) + hostlen); - if (!a) { - syslog(LOG_ERR, "Calloc failed for static lease on interface %s", - iface->ifname); - return -1; - } - a->addr = ntohl(lease->ipaddr.s_addr); - memcpy(a->hwaddr, lease->mac.ether_addr_octet, sizeof(a->hwaddr)); - memcpy(a->hostname, lease->hostname, hostlen); - a->valid_until = LONG_MAX; - - // 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); - } + md5_begin(&md5); + md5_hash(secretbytes, sizeof(secretbytes), &md5); + md5_hash(&fr_msg, sizeof(fr_msg), &md5); + md5_end(auth_o->key, &md5); - if (!a->head.next) - free(a); + for (size_t i = 0; i < sizeof(secretbytes); ++i) { + secretbytes[i] ^= 0x36; + secretbytes[i] ^= 0x5c; } - // 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)) { - list_del(&a->head); - free(a); - } - } + 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; - if (iface->dhcpv4_leasetime < 60) - iface->dhcpv4_leasetime = 43200; + if (sendto(iface->dhcpv4_event.uloop.fd, &fr_msg, PACKET_SIZE(&fr_msg, cookie), + MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest)) < 0) + syslog(LOG_ERR, "Failed to send %s to %s - %s: %m", dhcpv4_msg_to_string(msg), + odhcpd_print_mac(a->hwaddr, sizeof(a->hwaddr)), inet_ntoa(dest.sin_addr)); + else + syslog(LOG_NOTICE, "Sent %s to %s - %s", dhcpv4_msg_to_string(msg), + odhcpd_print_mac(a->hwaddr, sizeof(a->hwaddr)), inet_ntoa(dest.sin_addr)); +} - 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)) { - struct dhcpv4_assignment *a = list_first_entry(&iface->dhcpv4_assignments, - struct dhcpv4_assignment, head); - list_del(&a->head); - free(a); - } +static void dhcpv4_fr_timer(struct uloop_timeout *event) +{ + struct dhcp_assignment *a = container_of(event, struct dhcp_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); +} - } - return 0; +static void dhcpv4_fr_start(struct dhcp_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_delay_timer(struct uloop_timeout *event) +{ + struct dhcp_assignment *a = container_of(event, struct dhcp_assignment, fr_timer); + struct interface *iface = a->iface; -static void dhcpv4_put(struct dhcpv4_message *msg, uint8_t **cookie, - uint8_t type, uint8_t len, const void *data) + (iface->dhcpv4_event.uloop.fd == -1 ? dhcpv4_fr_rand_delay(a) : dhcpv4_fr_start(a)); +} + +static void dhcpv4_fr_rand_delay(struct dhcp_assignment *a) { - uint8_t *c = *cookie; - if (*cookie + 2 + len > (uint8_t*)&msg[1]) - return; +#define MIN_DELAY 500 +#define MAX_FUZZ 500 + int msecs; - *c++ = type; - *c++ = len; - memcpy(c, data, len); + odhcpd_urandom(&msecs, sizeof(msecs)); + + msecs = labs(msecs)%MAX_FUZZ + MIN_DELAY; - *cookie = c + len; + uloop_timeout_set(&a->fr_timer, msecs); + a->fr_timer.cb = dhcpv4_fr_delay_timer; } +static void dhcpv4_fr_stop(struct dhcp_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; +} -// Simple DHCPv6-server for information requests +/* Handler for DHCPv4 messages */ static void handle_dhcpv4(void *addr, void *data, size_t len, struct interface *iface, _unused void *dest_addr) { + struct dhcpv4_message *req = data; + 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; + syslog(LOG_NOTICE, "Got DHCPv4 request on %s", iface->name); - 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"); + if (!iface->dhcpv4_start_ip.s_addr && !iface->dhcpv4_end_ip.s_addr) { + syslog(LOG_ERR, "No DHCP range available on %s", iface->name); return; } - struct ifreq ifr = {.ifr_name = ""}; - strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name)); + int sock = iface->dhcpv4_event.uloop.fd; 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.sin_addr, + .siaddr = iface->dhcpv4_local, }; memcpy(reply.chaddr, req->chaddr, sizeof(reply.chaddr)); @@ -309,23 +631,33 @@ static void handle_dhcpv4(void *addr, void *data, size_t len, 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; + size_t reqopts_len = 0; char hostname[256]; - hostname[0] = 0; + char reqopts[256]; + bool accept_fr_nonce = false; + bool incl_fr_opt = false; 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) { + if (opt->type == DHCPV4_OPT_MESSAGE && opt->len == 1) reqmsg = opt->data[0]; + else if (opt->type == DHCPV4_OPT_REQOPTS && opt->len > 0) { + reqopts_len = opt->len; + memcpy(reqopts, opt->data, reqopts_len); + reqopts[reqopts_len] = 0; } else if (opt->type == DHCPV4_OPT_HOSTNAME && opt->len > 0) { - memcpy(hostname, opt->data, opt->len); - hostname[opt->len] = 0; - } else if (opt->type == DHCPV4_OPT_IPADDRESS && opt->len == 4) { + 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)) + else if (opt->type == DHCPV4_OPT_SERVERID && opt->len == 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]; @@ -334,84 +666,147 @@ static void handle_dhcpv4(void *addr, void *data, size_t len, 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); + 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 && - reqmsg != DHCPV4_MSG_INFORM && reqmsg != DHCPV4_MSG_DECLINE && - reqmsg != DHCPV4_MSG_RELEASE) + reqmsg != DHCPV4_MSG_INFORM && reqmsg != DHCPV4_MSG_DECLINE && + reqmsg != DHCPV4_MSG_RELEASE) return; - struct dhcpv4_assignment *lease = NULL; + struct dhcp_assignment *a = 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, hostname); + a = dhcpv4_lease(iface, reqmsg, req->chaddr, reqaddr, + &leasetime, hostname, hostname_len, + accept_fr_nonce, &incl_fr_opt, &fr_serverid, + reqopts, reqopts_len); - if (!lease) { + if (!a) { if (reqmsg == DHCPV4_MSG_REQUEST) msg = DHCPV4_MSG_NAK; else if (reqmsg == DHCPV4_MSG_DISCOVER) return; - } else if (reqmsg == DHCPV4_MSG_DISCOVER) { + } 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 != a->addr) || + (req->ciaddr.s_addr && req->ciaddr.s_addr != a->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 %x:%x:%x:%x:%x:%x", - dhcpv4_msg_to_string(reqmsg), - req->chaddr[0],req->chaddr[1],req->chaddr[2], - req->chaddr[3],req->chaddr[4],req->chaddr[5]); + syslog(LOG_NOTICE, "Received %s from %s on %s", dhcpv4_msg_to_string(reqmsg), + odhcpd_print_mac(req->chaddr, req->hlen), iface->name); +#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.sin_addr); + dhcpv4_put(&reply, &cookie, DHCPV4_OPT_SERVERID, 4, &serverid); + + if (a) { + uint32_t val; - if (lease) { - reply.yiaddr.s_addr = htonl(lease->addr); + reply.yiaddr.s_addr = a->addr; - uint32_t val = htonl(iface->dhcpv4_leasetime); + val = htonl(leasetime); dhcpv4_put(&reply, &cookie, DHCPV4_OPT_LEASETIME, 4, &val); - val = htonl(500 * iface->dhcpv4_leasetime / 1000); - dhcpv4_put(&reply, &cookie, DHCPV4_OPT_RENEW, 4, &val); + if (leasetime != UINT32_MAX) { + val = htonl(500 * leasetime / 1000); + dhcpv4_put(&reply, &cookie, DHCPV4_OPT_RENEW, 4, &val); - val = htonl(875 * iface->dhcpv4_leasetime / 1000); - dhcpv4_put(&reply, &cookie, DHCPV4_OPT_REBIND, 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); + dhcpv4_put(&reply, &cookie, DHCPV4_OPT_NETMASK, 4, + &iface->dhcpv4_mask.s_addr); - if (lease->hostname[0]) + if (a->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); + strlen(a->hostname), a->hostname); + + 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, a->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; + + 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); dhcpv4_put(&reply, &cookie, DHCPV4_OPT_MTU, 2, &mtu); } - if (iface->search && iface->search_len <= 255) { + 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]) { + 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); @@ -421,14 +816,14 @@ static void handle_dhcpv4(void *addr, void *data, size_t len, } if (iface->dhcpv4_router_cnt == 0) - dhcpv4_put(&reply, &cookie, DHCPV4_OPT_ROUTER, 4, &ifaddr.sin_addr); + 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.sin_addr); + 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); @@ -465,184 +860,281 @@ static void handle_dhcpv4(void *addr, void *data, size_t len, dest.sin_addr.s_addr = INADDR_BROADCAST; dest.sin_port = htons(DHCPV4_CLIENT_PORT); } else { + struct arpreq arp = {.arp_flags = ATF_COM}; + /* * 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 %x:%x:%x:%x:%x:%x - %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)); + if (ioctl(sock, SIOCSARP, &arp) < 0) + syslog(LOG_ERR, "ioctl(SIOCSARP): %m"); } - sendto(sock, &reply, sizeof(reply), MSG_DONTWAIT, - (struct sockaddr*)&dest, sizeof(dest)); + if (sendto(sock, &reply, PACKET_SIZE(&reply, cookie), MSG_DONTWAIT, + (struct sockaddr*)&dest, sizeof(dest)) < 0) + syslog(LOG_ERR, "Failed to send %s to %s - %s: %m", + dhcpv4_msg_to_string(msg), + dest.sin_addr.s_addr == INADDR_BROADCAST ? + "ff:ff:ff:ff:ff:ff": odhcpd_print_mac(req->chaddr, req->hlen), + inet_ntoa(dest.sin_addr)); + else + syslog(LOG_NOTICE, "Sent %s to %s - %s", + dhcpv4_msg_to_string(msg), + dest.sin_addr.s_addr == INADDR_BROADCAST ? + "ff:ff:ff:ff:ff:ff": odhcpd_print_mac(req->chaddr, req->hlen), + inet_ntoa(dest.sin_addr)); + + +#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_test(struct interface *iface, uint32_t try) +static bool dhcpv4_insert_assignment(struct list_head *list, struct dhcp_assignment *a, + uint32_t addr) { - struct dhcpv4_assignment *c; - list_for_each_entry(c, &iface->dhcpv4_assignments, head) { - if (c->addr == try) { + uint32_t h_addr = ntohl(addr); + struct dhcp_assignment *c; + + list_for_each_entry(c, list, head) { + uint32_t c_addr = ntohl(c->addr); + + if (c_addr == h_addr) return false; - } + + if (c_addr > h_addr) + break; } + + /* Insert new node before c (might match list head) */ + a->addr = addr; + list_add_tail(&a->head, &c->head); + return true; } -static bool dhcpv4_assign(struct interface *iface, - struct dhcpv4_assignment *assign, uint32_t raddr) +static char* ip4toa(uint32_t addr) { - uint32_t start = ntohl(iface->dhcpv4_start.s_addr); - uint32_t end = ntohl(iface->dhcpv4_end.s_addr); + static char buf[16]; + + snprintf(buf, sizeof(buf), "%u.%u.%u.%u", + ((uint8_t *)&addr)[0], ((uint8_t *)&addr)[1], + ((uint8_t *)&addr)[2], ((uint8_t *)&addr)[3]); + + return buf; +} + +static bool dhcpv4_assign(struct interface *iface, struct dhcp_assignment *a, + uint32_t raddr) +{ + 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; + uint32_t seed = 0; + bool assigned; + + /* Preconfigured IP address by static lease */ + if (a->addr) { + assigned = dhcpv4_insert_assignment(&iface->dhcpv4_assignments, + a, a->addr); + + if (assigned) + syslog(LOG_INFO, "Assigning static IP: %s", ip4toa(a->addr)); - // 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_DEBUG, "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; + return assigned; } - // 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]; + /* try to assign the IP the client asked for */ + if (start <= ntohl(raddr) && ntohl(raddr) <= end && + !config_find_lease_by_ipaddr(raddr)) { + assigned = dhcpv4_insert_assignment(&iface->dhcpv4_assignments, + a, raddr); + + if (assigned) { + syslog(LOG_INFO, "Assigning the IP the client asked for: %s", + ip4toa(a->addr)); + + return true; + } + } + + /* Seed RNG with checksum of hwaddress */ + for (size_t i = 0; i < sizeof(a->hwaddr); ++i) { + /* Knuth's multiplicative method */ + uint8_t o = a->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_DEBUG, "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); + for (uint32_t i = 0, try = (((uint32_t)rand()) % count) + start; i < count; + ++i, try = (((try - start) + 1) % count) + start) { + uint32_t n_try = htonl(try); + + if (config_find_lease_by_ipaddr(n_try)) + continue; + + assigned = dhcpv4_insert_assignment(&iface->dhcpv4_assignments, + a, n_try); + + if (assigned) { + syslog(LOG_INFO, "Assigning mapped IP: %s (try %u of %u)", + ip4toa(a->addr), i + 1, count); + return true; } - try = (((try - start) + 1) % count) + start; } - syslog(LOG_DEBUG, "can't assign any IP address -> address space is full"); + 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, - const char *hostname) +static struct dhcp_assignment* +dhcpv4_lease(struct interface *iface, 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, const char* reqopts, const size_t reqopts_len) { - struct dhcpv4_assignment *lease = NULL; - uint32_t raddr = ntohl(reqaddr.s_addr); + struct dhcp_assignment *a = find_assignment_by_hwaddr(iface, mac); + struct lease *l = config_find_lease_by_mac(mac); 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 (c->valid_until < now) { - list_del(&c->head); - free(c); - } + if (l && a && a->lease != l) { + free_assignment(a); + a = NULL; + } + + 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; - size_t hostlen = strlen(hostname) + 1; - if (!a && !iface->no_dynamic_dhcp) { // Create new binding - a = calloc(1, sizeof(*a) + hostlen); - if (!a) { - syslog(LOG_ERR, "Failed to calloc binding on interface %s", iface->ifname); - return NULL; - } - memcpy(a->hwaddr, mac, sizeof(a->hwaddr)); - memcpy(a->hostname, hostname, hostlen); + if (!a) { + if (!iface->no_dynamic_dhcp || l) { + /* Create new binding */ + a = alloc_assignment(0); + if (!a) { + syslog(LOG_ERR, "Failed to alloc assignment on interface %s", + iface->ifname); + return NULL; + } + memcpy(a->hwaddr, mac, sizeof(a->hwaddr)); + /* Set valid time to 0 for static lease indicating */ + /* infinite lifetime otherwise current time */ + a->valid_until = l ? 0 : now; + a->dhcp_free_cb = dhcpv4_free_assignment; + a->iface = iface; + a->flags = OAF_DHCPV4; + a->addr = l ? l->ipaddr : INADDR_ANY; - assigned = dhcpv4_assign(iface, a, raddr); - } + assigned = dhcpv4_assign(iface, a, reqaddr); + + if (l) { + a->flags |= OAF_STATIC; + + if (l->hostname) + a->hostname = strdup(l->hostname); - if (assigned && !a->hostname[0] && hostname) { - a = realloc(a, sizeof(*a) + hostlen); - if (!a) { - syslog(LOG_ERR, "Failed to realloc binding on interface %s", iface->ifname); - return NULL; + if (l->leasetime) + a->leasetime = l->leasetime; + + list_add(&a->lease_list, &l->assignments); + a->lease = l; + } } - memcpy(a->hostname, hostname, hostlen); + } else if (((a->addr & iface->dhcpv4_mask.s_addr) != + (iface->dhcpv4_start_ip.s_addr & iface->dhcpv4_mask.s_addr)) && + !(a->flags & OAF_STATIC)) { + list_del_init(&a->head); + a->addr = INADDR_ANY; - // Fixup list - a->head.next->prev = &a->head; - a->head.prev->next = &a->head; + assigned = dhcpv4_assign(iface, a, reqaddr); } - // Was only a solicitation: mark binding for removal - if (assigned && a->valid_until < now) { - a->valid_until = (msg == DHCPV4_MSG_DISCOVER) ? 0 : - (now + iface->dhcpv4_leasetime); - } else if (!assigned && a) { // Cleanup failed assignment - free(a); + if (assigned) { + uint32_t my_leasetime; + + if (a->leasetime) + my_leasetime = a->leasetime; + else + my_leasetime = iface->dhcpv4_leasetime; + + if ((*leasetime == 0) || (my_leasetime < *leasetime)) + *leasetime = my_leasetime; + + 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 { + if ((!(a->flags & OAF_STATIC) || !a->hostname) && 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; + + if (odhcpd_valid_hostname(a->hostname)) + a->flags &= ~OAF_BROKEN_HOSTNAME; + else + a->flags |= OAF_BROKEN_HOSTNAME; + } + } + + if (reqopts_len > 0) { + a->reqopts = realloc(a->reqopts, reqopts_len + 1); + if (a->reqopts) { + memcpy(a->reqopts, reqopts, reqopts_len); + a->reqopts[reqopts_len] = 0; + } + } + + 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)); + } + } else if (!assigned && a) { + /* Cleanup failed assignment */ + free_assignment(a); a = NULL; } - if (assigned && a) - lease = a; - } else if (msg == DHCPV4_MSG_RELEASE) { - if (a && a->valid_until != LONG_MAX) - a->valid_until = 0; - } else if (msg == DHCPV4_MSG_DECLINE && a && a->valid_until != LONG_MAX) { - memset(a->hwaddr, 0, sizeof(a->hwaddr)); - a->valid_until = now + 3600; // Block address for 1h + } 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(); + dhcpv6_ia_write_statefile(); - return lease; + return a; } -