***/
#include <sys/ioctl.h>
-#include <netinet/if_ether.h>
-
-#include "siphash24.h"
#include "sd-dhcp-server.h"
-#include "dhcp-server-internal.h"
+
#include "dhcp-internal.h"
+#include "dhcp-server-internal.h"
+#include "in-addr-util.h"
+#include "siphash24.h"
+#include "string-util.h"
-#define DHCP_DEFAULT_LEASE_TIME 3600 /* one hour */
+#define DHCP_DEFAULT_LEASE_TIME_USEC USEC_PER_HOUR
+#define DHCP_MAX_LEASE_TIME_USEC (USEC_PER_HOUR*12)
+
+/* configures the server's address and subnet, and optionally the pool's size and offset into the subnet
+ * the whole pool must fit into the subnet, and may not contain the first (any) nor last (broadcast) address
+ * moreover, the server's own address may be in the pool, and is in that case reserved in order not to
+ * accidentally hand it out */
+int sd_dhcp_server_configure_pool(sd_dhcp_server *server, struct in_addr *address, unsigned char prefixlen, uint32_t offset, uint32_t size) {
+ struct in_addr netmask_addr;
+ be32_t netmask;
+ uint32_t server_off, broadcast_off, size_max;
-int sd_dhcp_server_set_lease_pool(sd_dhcp_server *server,
- struct in_addr *address,
- size_t size) {
assert_return(server, -EINVAL);
assert_return(address, -EINVAL);
- assert_return(address->s_addr, -EINVAL);
- assert_return(size, -EINVAL);
- assert_return(server->pool_start == htobe32(INADDR_ANY), -EBUSY);
- assert_return(!server->pool_size, -EBUSY);
- assert_return(!server->bound_leases, -EBUSY);
+ assert_return(address->s_addr != INADDR_ANY, -EINVAL);
+ assert_return(prefixlen <= 32, -ERANGE);
+ assert_return(server->address == INADDR_ANY, -EBUSY);
+
+ assert_se(in_addr_prefixlen_to_netmask(&netmask_addr, prefixlen));
+ netmask = netmask_addr.s_addr;
+
+ server_off = be32toh(address->s_addr & ~netmask);
+ broadcast_off = be32toh(~netmask);
+
+ /* the server address cannot be the subnet address */
+ assert_return(server_off != 0, -ERANGE);
+
+ /* nor the broadcast address */
+ assert_return(server_off != broadcast_off, -ERANGE);
+
+ /* 0 offset means we should set a default, we skip the first (subnet) address
+ and take the next one */
+ if (offset == 0)
+ offset = 1;
+
+ size_max = (broadcast_off + 1) /* the number of addresses in the subnet */
+ - offset /* exclude the addresses before the offset */
+ - 1; /* exclude the last (broadcast) address */
+
+ /* The pool must contain at least one address */
+ assert_return(size_max >= 1, -ERANGE);
+
+ if (size != 0)
+ assert_return(size <= size_max, -ERANGE);
+ else
+ size = size_max;
server->bound_leases = new0(DHCPLease*, size);
if (!server->bound_leases)
return -ENOMEM;
- server->pool_start = address->s_addr;
+ server->pool_offset = offset;
server->pool_size = size;
- return 0;
-}
-
-int sd_dhcp_server_set_address(sd_dhcp_server *server, struct in_addr *address,
- unsigned char prefixlen) {
- assert_return(server, -EINVAL);
- assert_return(address, -EINVAL);
- assert_return(address->s_addr, -EINVAL);
- assert_return(prefixlen <= 32, -ERANGE);
- assert_return(server->address == htobe32(INADDR_ANY), -EBUSY);
- assert_return(server->netmask == htobe32(INADDR_ANY), -EBUSY);
-
server->address = address->s_addr;
- server->netmask = htobe32(0xfffffffflu << (32 - prefixlen));
+ server->netmask = netmask;
+ server->subnet = address->s_addr & netmask;
+
+ if (server_off >= offset && server_off - offset < size)
+ server->bound_leases[server_off - offset] = &server->invalid_lease;
return 0;
}
bool sd_dhcp_server_is_running(sd_dhcp_server *server) {
- assert_return(server, -EINVAL);
+ assert_return(server, false);
return !!server->receive_message;
}
sd_dhcp_server *sd_dhcp_server_ref(sd_dhcp_server *server) {
- if (server)
- assert_se(REFCNT_INC(server->n_ref) >= 2);
+
+ if (!server)
+ return NULL;
+
+ assert(server->n_ref >= 1);
+ server->n_ref++;
return server;
}
-unsigned long client_id_hash_func(const void *p,
- const uint8_t hash_key[HASH_KEY_SIZE]) {
- uint64_t u;
+void client_id_hash_func(const void *p, struct siphash *state) {
const DHCPClientId *id = p;
assert(id);
assert(id->length);
assert(id->data);
- siphash24((uint8_t*) &u, id->data, id->length, hash_key);
-
- return (unsigned long) u;
+ siphash24_compress(&id->length, sizeof(id->length), state);
+ siphash24_compress(id->data, id->length, state);
}
int client_id_compare_func(const void *_a, const void *_b) {
if (!server)
return NULL;
- if (REFCNT_DEC(server->n_ref) > 0)
+ assert(server->n_ref >= 1);
+ server->n_ref--;
+
+ if (server->n_ref > 0)
return NULL;
log_dhcp_server(server, "UNREF");
sd_event_unref(server->event);
+ free(server->timezone);
+ free(server->dns);
+ free(server->ntp);
+
while ((lease = hashmap_steal_first(server->leases_by_client_id)))
dhcp_lease_free(lease);
hashmap_free(server->leases_by_client_id);
if (!server)
return -ENOMEM;
- server->n_ref = REFCNT_INIT;
+ server->n_ref = 1;
server->fd_raw = -1;
server->fd = -1;
server->address = htobe32(INADDR_ANY);
server->netmask = htobe32(INADDR_ANY);
- server->index = ifindex;
+ server->ifindex = ifindex;
server->leases_by_client_id = hashmap_new(&client_id_hash_ops);
+ server->default_lease_time = DIV_ROUND_UP(DHCP_DEFAULT_LEASE_TIME_USEC, USEC_PER_SEC);
+ server->max_lease_time = DIV_ROUND_UP(DHCP_MAX_LEASE_TIME_USEC, USEC_PER_SEC);
*ret = server;
server = NULL;
union sockaddr_union link = {
.ll.sll_family = AF_PACKET,
.ll.sll_protocol = htons(ETH_P_IP),
- .ll.sll_ifindex = server->index,
+ .ll.sll_ifindex = server->ifindex,
.ll.sll_halen = ETH_ALEN,
};
- int r;
assert(server);
- assert(server->index > 0);
+ assert(server->ifindex > 0);
assert(server->address);
assert(packet);
assert(len > sizeof(DHCPPacket));
packet->dhcp.yiaddr,
DHCP_PORT_CLIENT, len);
- r = dhcp_network_send_raw_socket(server->fd_raw, &link, packet, len);
- if (r < 0)
- return r;
-
- return 0;
+ return dhcp_network_send_raw_socket(server->fd_raw, &link, packet, len);
}
static int dhcp_server_send_udp(sd_dhcp_server *server, be32_t destination,
pktinfo = (struct in_pktinfo*) CMSG_DATA(cmsg);
assert(pktinfo);
- pktinfo->ipi_ifindex = server->index;
+ pktinfo->ipi_ifindex = server->ifindex;
pktinfo->ipi_spec_dst.s_addr = server->address;
r = sendmsg(server->fd, &msg, 0);
if (r < 0)
return r;
+ if (server->n_dns > 0) {
+ r = dhcp_option_append(
+ &packet->dhcp, req->max_optlen, &offset, 0,
+ DHCP_OPTION_DOMAIN_NAME_SERVER,
+ sizeof(struct in_addr) * server->n_dns, server->dns);
+ if (r < 0)
+ return r;
+ }
+
+ if (server->n_ntp > 0) {
+ r = dhcp_option_append(
+ &packet->dhcp, req->max_optlen, &offset, 0,
+ DHCP_OPTION_NTP_SERVER,
+ sizeof(struct in_addr) * server->n_ntp, server->ntp);
+ if (r < 0)
+ return r;
+ }
+
+ if (server->timezone) {
+ r = dhcp_option_append(
+ &packet->dhcp, req->max_optlen, &offset, 0,
+ DHCP_OPTION_NEW_TZDB_TIMEZONE,
+ strlen(server->timezone), server->timezone);
+ if (r < 0)
+ return r;
+ }
+
r = dhcp_server_send_packet(server, req, packet, DHCP_ACK, offset);
if (r < 0)
return r;
if (r < 0)
return r;
- r = dhcp_server_send_packet(server, req, packet, DHCP_NAK, offset);
- if (r < 0)
- return r;
-
- return 0;
+ return dhcp_server_send_packet(server, req, packet, DHCP_NAK, offset);
}
static int server_send_forcerenew(sd_dhcp_server *server, be32_t address,
return 0;
}
-static int parse_request(uint8_t code, uint8_t len, const uint8_t *option,
- void *user_data) {
- DHCPRequest *req = user_data;
+static int parse_request(uint8_t code, uint8_t len, const void *option, void *userdata) {
+ DHCPRequest *req = userdata;
assert(req);
DEFINE_TRIVIAL_CLEANUP_FUNC(DHCPRequest*, dhcp_request_free);
#define _cleanup_dhcp_request_free_ _cleanup_(dhcp_request_freep)
-static int ensure_sane_request(DHCPRequest *req, DHCPMessage *message) {
+static int ensure_sane_request(sd_dhcp_server *server, DHCPRequest *req, DHCPMessage *message) {
assert(req);
assert(message);
req->message = message;
- /* set client id based on mac address if client did not send an explicit
+ /* set client id based on MAC address if client did not send an explicit
one */
if (!req->client_id.data) {
- uint8_t *data;
+ void *data;
- data = new0(uint8_t, ETH_ALEN + 1);
+ data = malloc0(ETH_ALEN + 1);
if (!data)
return -ENOMEM;
+ ((uint8_t*) data)[0] = 0x01;
+ memcpy((uint8_t*) data + 1, &message->chaddr, ETH_ALEN);
+
req->client_id.length = ETH_ALEN + 1;
req->client_id.data = data;
- req->client_id.data[0] = 0x01;
- memcpy(&req->client_id.data[1], &message->chaddr, ETH_ALEN);
}
if (req->max_optlen < DHCP_MIN_OPTIONS_SIZE)
req->max_optlen = DHCP_MIN_OPTIONS_SIZE;
- if (!req->lifetime)
- req->lifetime = DHCP_DEFAULT_LEASE_TIME;
+ if (req->lifetime <= 0)
+ req->lifetime = MAX(1ULL, server->default_lease_time);
+
+ if (server->max_lease_time > 0 && req->lifetime > server->max_lease_time)
+ req->lifetime = server->max_lease_time;
return 0;
}
if (!server->pool_size)
return -EINVAL;
- if (be32toh(requested_ip) < be32toh(server->pool_start) ||
- be32toh(requested_ip) >= be32toh(server->pool_start) +
- + server->pool_size)
- return -EINVAL;
+ if (be32toh(requested_ip) < (be32toh(server->subnet) | server->pool_offset) ||
+ be32toh(requested_ip) >= (be32toh(server->subnet) | (server->pool_offset + server->pool_size)))
+ return -ERANGE;
- return be32toh(requested_ip) - be32toh(server->pool_start);
+ return be32toh(requested_ip & ~server->netmask) - server->pool_offset;
}
+#define HASH_KEY SD_ID128_MAKE(0d,1d,fe,bd,f1,24,bd,b3,47,f1,dd,6e,73,21,93,30)
+
int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
size_t length) {
_cleanup_dhcp_request_free_ DHCPRequest *req = NULL;
if (type < 0)
return 0;
- r = ensure_sane_request(req, message);
+ r = ensure_sane_request(server, req, message);
if (r < 0)
/* this only fails on critical errors */
return r;
&req->client_id);
switch(type) {
- case DHCP_DISCOVER:
- {
+
+ case DHCP_DISCOVER: {
be32_t address = INADDR_ANY;
unsigned i;
if (existing_lease)
address = existing_lease->address;
else {
+ struct siphash state;
+ uint64_t hash;
+ uint32_t next_offer;
+
+ /* even with no persistence of leases, we try to offer the same client
+ the same IP address. we do this by using the hash of the client id
+ as the offset into the pool of leases when finding the next free one */
+
+ siphash24_init(&state, HASH_KEY.bytes);
+ client_id_hash_func(&req->client_id, &state);
+ siphash24_finalize((uint8_t*)&hash, &state);
+ next_offer = hash % server->pool_size;
+
for (i = 0; i < server->pool_size; i++) {
- if (!server->bound_leases[server->next_offer]) {
- address = htobe32(be32toh(server->pool_start) + server->next_offer);
+ if (!server->bound_leases[next_offer]) {
+ address = server->subnet | htobe32(server->pool_offset + next_offer);
break;
} else
- server->next_offer = (server->next_offer + 1) % server->pool_size;
+ next_offer = (next_offer + 1) % server->pool_size;
}
}
return 1;
- break;
- case DHCP_REQUEST:
- {
+ case DHCP_REQUEST: {
be32_t address;
bool init_reboot = false;
int pool_offset;
if (pool_offset >= 0 &&
server->bound_leases[pool_offset] == existing_lease) {
DHCPLease *lease;
- usec_t time_now;
+ usec_t time_now = 0;
if (!existing_lease) {
lease = new0(DHCPLease, 1);
r = sd_event_now(server->event,
clock_boottime_or_monotonic(),
&time_now);
- if (r < 0)
- time_now = now(clock_boottime_or_monotonic());
+ if (r < 0) {
+ if (!existing_lease)
+ dhcp_lease_free(lease);
+ return r;
+ }
+
lease->expiration = req->lifetime * USEC_PER_SEC + time_now;
r = server_send_ack(server, req, address);
break;
}
+
case DHCP_RELEASE: {
int pool_offset;
.msg_controllen = sizeof(cmsgbuf),
};
struct cmsghdr *cmsg;
- int buflen = 0, len, r;
+ int buflen = 0, len;
assert(server);
- r = ioctl(fd, FIONREAD, &buflen);
- if (r < 0)
- return r;
+ if (ioctl(fd, FIONREAD, &buflen) < 0)
+ return -errno;
if (buflen < 0)
return -EIO;
else if ((size_t)len < sizeof(DHCPMessage))
return 0;
- for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+ CMSG_FOREACH(cmsg, &msg) {
if (cmsg->cmsg_level == IPPROTO_IP &&
cmsg->cmsg_type == IP_PKTINFO &&
cmsg->cmsg_len == CMSG_LEN(sizeof(struct in_pktinfo))) {
/* TODO figure out if this can be done as a filter on
* the socket, like for IPv6 */
- if (server->index != info->ipi_ifindex)
+ if (server->ifindex != info->ipi_ifindex)
return 0;
break;
for (i = 0; i < server->pool_size; i++) {
DHCPLease *lease = server->bound_leases[i];
- if (!lease)
+ if (!lease || lease == &server->invalid_lease)
continue;
r = server_send_forcerenew(server, lease->address,
return r;
}
+
+int sd_dhcp_server_set_timezone(sd_dhcp_server *server, const char *tz) {
+ int r;
+
+ assert_return(server, -EINVAL);
+ assert_return(timezone_is_valid(tz), -EINVAL);
+
+ if (streq_ptr(tz, server->timezone))
+ return 0;
+
+ r = free_and_strdup(&server->timezone, tz);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+int sd_dhcp_server_set_max_lease_time(sd_dhcp_server *server, uint32_t t) {
+ assert_return(server, -EINVAL);
+
+ if (t == server->max_lease_time)
+ return 0;
+
+ server->max_lease_time = t;
+ return 1;
+}
+
+int sd_dhcp_server_set_default_lease_time(sd_dhcp_server *server, uint32_t t) {
+ assert_return(server, -EINVAL);
+
+ if (t == server->default_lease_time)
+ return 0;
+
+ server->default_lease_time = t;
+ return 1;
+}
+
+int sd_dhcp_server_set_dns(sd_dhcp_server *server, const struct in_addr dns[], unsigned n) {
+ assert_return(server, -EINVAL);
+ assert_return(dns || n <= 0, -EINVAL);
+
+ if (server->n_dns == n &&
+ memcmp(server->dns, dns, sizeof(struct in_addr) * n) == 0)
+ return 0;
+
+ if (n <= 0) {
+ server->dns = mfree(server->dns);
+ server->n_dns = 0;
+ } else {
+ struct in_addr *c;
+
+ c = newdup(struct in_addr, dns, n);
+ if (!c)
+ return -ENOMEM;
+
+ free(server->dns);
+ server->dns = c;
+ server->n_dns = n;
+ }
+
+ return 1;
+}
+
+int sd_dhcp_server_set_ntp(sd_dhcp_server *server, const struct in_addr ntp[], unsigned n) {
+ assert_return(server, -EINVAL);
+ assert_return(ntp || n <= 0, -EINVAL);
+
+ if (server->n_ntp == n &&
+ memcmp(server->ntp, ntp, sizeof(struct in_addr) * n) == 0)
+ return 0;
+
+ if (n <= 0) {
+ server->ntp = mfree(server->ntp);
+ server->n_ntp = 0;
+ } else {
+ struct in_addr *c;
+
+ c = newdup(struct in_addr, ntp, n);
+ if (!c)
+ return -ENOMEM;
+
+ free(server->ntp);
+ server->ntp = c;
+ server->n_ntp = n;
+ }
+
+ return 1;
+}
projects / thirdparty / systemd.git / blobdiff