| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| /*** |
| This file is part of systemd. |
| |
| Copyright (C) 2014-2015 Intel Corporation. All rights reserved. |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #include <errno.h> |
| #include <string.h> |
| #include <sys/ioctl.h> |
| #include <linux/if_infiniband.h> |
| |
| #include "sd-dhcp6-client.h" |
| |
| #include "alloc-util.h" |
| #include "dhcp-identifier.h" |
| #include "dhcp6-internal.h" |
| #include "dhcp6-lease-internal.h" |
| #include "dhcp6-protocol.h" |
| #include "dns-domain.h" |
| #include "fd-util.h" |
| #include "hostname-util.h" |
| #include "in-addr-util.h" |
| #include "network-internal.h" |
| #include "random-util.h" |
| #include "socket-util.h" |
| #include "string-table.h" |
| #include "util.h" |
| |
| #define MAX_MAC_ADDR_LEN INFINIBAND_ALEN |
| |
| struct sd_dhcp6_client { |
| unsigned n_ref; |
| |
| enum DHCP6State state; |
| sd_event *event; |
| int event_priority; |
| int ifindex; |
| struct in6_addr local_address; |
| uint8_t mac_addr[MAX_MAC_ADDR_LEN]; |
| size_t mac_addr_len; |
| uint16_t arp_type; |
| DHCP6IA ia_na; |
| DHCP6IA ia_pd; |
| bool prefix_delegation; |
| be32_t transaction_id; |
| usec_t transaction_start; |
| struct sd_dhcp6_lease *lease; |
| int fd; |
| bool information_request; |
| be16_t *req_opts; |
| size_t req_opts_allocated; |
| size_t req_opts_len; |
| char *fqdn; |
| sd_event_source *receive_message; |
| usec_t retransmit_time; |
| uint8_t retransmit_count; |
| sd_event_source *timeout_resend; |
| sd_event_source *timeout_resend_expire; |
| sd_dhcp6_client_callback_t callback; |
| void *userdata; |
| struct duid duid; |
| size_t duid_len; |
| }; |
| |
| static const uint16_t default_req_opts[] = { |
| SD_DHCP6_OPTION_DNS_SERVERS, |
| SD_DHCP6_OPTION_DOMAIN_LIST, |
| SD_DHCP6_OPTION_NTP_SERVER, |
| SD_DHCP6_OPTION_SNTP_SERVERS, |
| }; |
| |
| const char * dhcp6_message_type_table[_DHCP6_MESSAGE_MAX] = { |
| [DHCP6_SOLICIT] = "SOLICIT", |
| [DHCP6_ADVERTISE] = "ADVERTISE", |
| [DHCP6_REQUEST] = "REQUEST", |
| [DHCP6_CONFIRM] = "CONFIRM", |
| [DHCP6_RENEW] = "RENEW", |
| [DHCP6_REBIND] = "REBIND", |
| [DHCP6_REPLY] = "REPLY", |
| [DHCP6_RELEASE] = "RELEASE", |
| [DHCP6_DECLINE] = "DECLINE", |
| [DHCP6_RECONFIGURE] = "RECONFIGURE", |
| [DHCP6_INFORMATION_REQUEST] = "INFORMATION-REQUEST", |
| [DHCP6_RELAY_FORW] = "RELAY-FORW", |
| [DHCP6_RELAY_REPL] = "RELAY-REPL", |
| }; |
| |
| DEFINE_STRING_TABLE_LOOKUP(dhcp6_message_type, int); |
| |
| const char * dhcp6_message_status_table[_DHCP6_STATUS_MAX] = { |
| [DHCP6_STATUS_SUCCESS] = "Success", |
| [DHCP6_STATUS_UNSPEC_FAIL] = "Unspecified failure", |
| [DHCP6_STATUS_NO_ADDRS_AVAIL] = "No addresses available", |
| [DHCP6_STATUS_NO_BINDING] = "Binding unavailable", |
| [DHCP6_STATUS_NOT_ON_LINK] = "Not on link", |
| [DHCP6_STATUS_USE_MULTICAST] = "Use multicast", |
| }; |
| |
| DEFINE_STRING_TABLE_LOOKUP(dhcp6_message_status, int); |
| |
| #define DHCP6_CLIENT_DONT_DESTROY(client) \ |
| _cleanup_(sd_dhcp6_client_unrefp) _unused_ sd_dhcp6_client *_dont_destroy_##client = sd_dhcp6_client_ref(client) |
| |
| static int client_start(sd_dhcp6_client *client, enum DHCP6State state); |
| |
| int sd_dhcp6_client_set_callback( |
| sd_dhcp6_client *client, |
| sd_dhcp6_client_callback_t cb, |
| void *userdata) { |
| |
| assert_return(client, -EINVAL); |
| |
| client->callback = cb; |
| client->userdata = userdata; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_ifindex(sd_dhcp6_client *client, int ifindex) { |
| |
| assert_return(client, -EINVAL); |
| assert_return(ifindex >= -1, -EINVAL); |
| assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY); |
| |
| client->ifindex = ifindex; |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_local_address( |
| sd_dhcp6_client *client, |
| const struct in6_addr *local_address) { |
| |
| assert_return(client, -EINVAL); |
| assert_return(local_address, -EINVAL); |
| assert_return(in_addr_is_link_local(AF_INET6, (const union in_addr_union *) local_address) > 0, -EINVAL); |
| |
| assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY); |
| |
| client->local_address = *local_address; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_mac( |
| sd_dhcp6_client *client, |
| const uint8_t *addr, size_t addr_len, |
| uint16_t arp_type) { |
| |
| assert_return(client, -EINVAL); |
| assert_return(addr, -EINVAL); |
| assert_return(addr_len > 0 && addr_len <= MAX_MAC_ADDR_LEN, -EINVAL); |
| assert_return(arp_type > 0, -EINVAL); |
| |
| assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY); |
| |
| if (arp_type == ARPHRD_ETHER) |
| assert_return(addr_len == ETH_ALEN, -EINVAL); |
| else if (arp_type == ARPHRD_INFINIBAND) |
| assert_return(addr_len == INFINIBAND_ALEN, -EINVAL); |
| else |
| return -EINVAL; |
| |
| if (client->mac_addr_len == addr_len && |
| memcmp(&client->mac_addr, addr, addr_len) == 0) |
| return 0; |
| |
| memcpy(&client->mac_addr, addr, addr_len); |
| client->mac_addr_len = addr_len; |
| client->arp_type = arp_type; |
| |
| return 0; |
| } |
| |
| static int client_ensure_duid(sd_dhcp6_client *client) { |
| if (client->duid_len != 0) |
| return 0; |
| |
| return dhcp_identifier_set_duid_en(&client->duid, &client->duid_len); |
| } |
| |
| /** |
| * Sets DUID. If duid is non-null, the DUID is set to duid_type + duid |
| * without further modification. Otherwise, if duid_type is supported, DUID |
| * is set based on that type. Otherwise, an error is returned. |
| */ |
| int sd_dhcp6_client_set_duid( |
| sd_dhcp6_client *client, |
| uint16_t duid_type, |
| const void *duid, |
| size_t duid_len) { |
| |
| int r; |
| assert_return(client, -EINVAL); |
| assert_return(duid_len == 0 || duid != NULL, -EINVAL); |
| assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY); |
| |
| if (duid != NULL) { |
| r = dhcp_validate_duid_len(duid_type, duid_len); |
| if (r < 0) |
| return r; |
| } |
| |
| if (duid != NULL) { |
| client->duid.type = htobe16(duid_type); |
| memcpy(&client->duid.raw.data, duid, duid_len); |
| client->duid_len = sizeof(client->duid.type) + duid_len; |
| } else if (duid_type == DUID_TYPE_EN) { |
| r = dhcp_identifier_set_duid_en(&client->duid, &client->duid_len); |
| if (r < 0) |
| return r; |
| } else |
| return -EOPNOTSUPP; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_iaid(sd_dhcp6_client *client, uint32_t iaid) { |
| assert_return(client, -EINVAL); |
| assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY); |
| |
| client->ia_na.ia_na.id = htobe32(iaid); |
| client->ia_pd.ia_pd.id = htobe32(iaid); |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_fqdn( |
| sd_dhcp6_client *client, |
| const char *fqdn) { |
| |
| assert_return(client, -EINVAL); |
| |
| /* Make sure FQDN qualifies as DNS and as Linux hostname */ |
| if (fqdn && |
| !(hostname_is_valid(fqdn, false) && dns_name_is_valid(fqdn) > 0)) |
| return -EINVAL; |
| |
| return free_and_strdup(&client->fqdn, fqdn); |
| } |
| |
| int sd_dhcp6_client_set_information_request(sd_dhcp6_client *client, int enabled) { |
| assert_return(client, -EINVAL); |
| assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY); |
| |
| client->information_request = enabled; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_get_information_request(sd_dhcp6_client *client, int *enabled) { |
| assert_return(client, -EINVAL); |
| assert_return(enabled, -EINVAL); |
| |
| *enabled = client->information_request; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_request_option(sd_dhcp6_client *client, uint16_t option) { |
| size_t t; |
| |
| assert_return(client, -EINVAL); |
| assert_return(client->state == DHCP6_STATE_STOPPED, -EBUSY); |
| |
| switch(option) { |
| |
| case SD_DHCP6_OPTION_DNS_SERVERS: |
| case SD_DHCP6_OPTION_DOMAIN_LIST: |
| case SD_DHCP6_OPTION_SNTP_SERVERS: |
| case SD_DHCP6_OPTION_NTP_SERVER: |
| case SD_DHCP6_OPTION_RAPID_COMMIT: |
| break; |
| |
| default: |
| return -EINVAL; |
| } |
| |
| for (t = 0; t < client->req_opts_len; t++) |
| if (client->req_opts[t] == htobe16(option)) |
| return -EEXIST; |
| |
| if (!GREEDY_REALLOC(client->req_opts, client->req_opts_allocated, |
| client->req_opts_len + 1)) |
| return -ENOMEM; |
| |
| client->req_opts[client->req_opts_len++] = htobe16(option); |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_set_prefix_delegation(sd_dhcp6_client *client, bool delegation) { |
| assert_return(client, -EINVAL); |
| |
| client->prefix_delegation = delegation; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_get_lease(sd_dhcp6_client *client, sd_dhcp6_lease **ret) { |
| assert_return(client, -EINVAL); |
| |
| if (!client->lease) |
| return -ENOMSG; |
| |
| if (ret) |
| *ret = client->lease; |
| |
| return 0; |
| } |
| |
| static void client_notify(sd_dhcp6_client *client, int event) { |
| assert(client); |
| |
| if (client->callback) |
| client->callback(client, event, client->userdata); |
| } |
| |
| static void client_set_lease(sd_dhcp6_client *client, sd_dhcp6_lease *lease) { |
| assert(client); |
| |
| if (client->lease) { |
| dhcp6_lease_clear_timers(&client->lease->ia); |
| sd_dhcp6_lease_unref(client->lease); |
| } |
| |
| client->lease = lease; |
| } |
| |
| static int client_reset(sd_dhcp6_client *client) { |
| assert(client); |
| |
| client_set_lease(client, NULL); |
| |
| client->receive_message = |
| sd_event_source_unref(client->receive_message); |
| |
| client->transaction_id = 0; |
| client->transaction_start = 0; |
| |
| client->ia_na.timeout_t1 = |
| sd_event_source_unref(client->ia_na.timeout_t1); |
| client->ia_na.timeout_t2 = |
| sd_event_source_unref(client->ia_na.timeout_t2); |
| |
| client->retransmit_time = 0; |
| client->retransmit_count = 0; |
| client->timeout_resend = sd_event_source_unref(client->timeout_resend); |
| client->timeout_resend_expire = |
| sd_event_source_unref(client->timeout_resend_expire); |
| |
| client->state = DHCP6_STATE_STOPPED; |
| |
| return 0; |
| } |
| |
| static void client_stop(sd_dhcp6_client *client, int error) { |
| DHCP6_CLIENT_DONT_DESTROY(client); |
| |
| assert(client); |
| |
| client_notify(client, error); |
| |
| client_reset(client); |
| } |
| |
| static int client_send_message(sd_dhcp6_client *client, usec_t time_now) { |
| _cleanup_free_ DHCP6Message *message = NULL; |
| struct in6_addr all_servers = |
| IN6ADDR_ALL_DHCP6_RELAY_AGENTS_AND_SERVERS_INIT; |
| size_t len, optlen = 512; |
| uint8_t *opt; |
| int r; |
| usec_t elapsed_usec; |
| be16_t elapsed_time; |
| |
| assert(client); |
| |
| len = sizeof(DHCP6Message) + optlen; |
| |
| message = malloc0(len); |
| if (!message) |
| return -ENOMEM; |
| |
| opt = (uint8_t *)(message + 1); |
| |
| message->transaction_id = client->transaction_id; |
| |
| switch(client->state) { |
| case DHCP6_STATE_INFORMATION_REQUEST: |
| message->type = DHCP6_INFORMATION_REQUEST; |
| |
| break; |
| |
| case DHCP6_STATE_SOLICITATION: |
| message->type = DHCP6_SOLICIT; |
| |
| r = dhcp6_option_append(&opt, &optlen, |
| SD_DHCP6_OPTION_RAPID_COMMIT, 0, NULL); |
| if (r < 0) |
| return r; |
| |
| r = dhcp6_option_append_ia(&opt, &optlen, &client->ia_na); |
| if (r < 0) |
| return r; |
| |
| if (client->fqdn) { |
| r = dhcp6_option_append_fqdn(&opt, &optlen, client->fqdn); |
| if (r < 0) |
| return r; |
| } |
| |
| if (client->prefix_delegation) { |
| r = dhcp6_option_append_pd(opt, optlen, &client->ia_pd); |
| if (r < 0) |
| return r; |
| |
| opt += r; |
| optlen -= r; |
| } |
| |
| break; |
| |
| case DHCP6_STATE_REQUEST: |
| case DHCP6_STATE_RENEW: |
| |
| if (client->state == DHCP6_STATE_REQUEST) |
| message->type = DHCP6_REQUEST; |
| else |
| message->type = DHCP6_RENEW; |
| |
| r = dhcp6_option_append(&opt, &optlen, SD_DHCP6_OPTION_SERVERID, |
| client->lease->serverid_len, |
| client->lease->serverid); |
| if (r < 0) |
| return r; |
| |
| r = dhcp6_option_append_ia(&opt, &optlen, &client->lease->ia); |
| if (r < 0) |
| return r; |
| |
| if (client->fqdn) { |
| r = dhcp6_option_append_fqdn(&opt, &optlen, client->fqdn); |
| if (r < 0) |
| return r; |
| } |
| |
| if (client->prefix_delegation) { |
| r = dhcp6_option_append_pd(opt, optlen, &client->lease->pd); |
| if (r < 0) |
| return r; |
| |
| opt += r; |
| optlen -= r; |
| } |
| |
| break; |
| |
| case DHCP6_STATE_REBIND: |
| message->type = DHCP6_REBIND; |
| |
| r = dhcp6_option_append_ia(&opt, &optlen, &client->lease->ia); |
| if (r < 0) |
| return r; |
| |
| if (client->fqdn) { |
| r = dhcp6_option_append_fqdn(&opt, &optlen, client->fqdn); |
| if (r < 0) |
| return r; |
| } |
| |
| if (client->prefix_delegation) { |
| r = dhcp6_option_append_pd(opt, optlen, &client->lease->pd); |
| if (r < 0) |
| return r; |
| |
| opt += r; |
| optlen -= r; |
| } |
| |
| break; |
| |
| case DHCP6_STATE_STOPPED: |
| case DHCP6_STATE_BOUND: |
| return -EINVAL; |
| } |
| |
| r = dhcp6_option_append(&opt, &optlen, SD_DHCP6_OPTION_ORO, |
| client->req_opts_len * sizeof(be16_t), |
| client->req_opts); |
| if (r < 0) |
| return r; |
| |
| assert(client->duid_len); |
| r = dhcp6_option_append(&opt, &optlen, SD_DHCP6_OPTION_CLIENTID, |
| client->duid_len, &client->duid); |
| if (r < 0) |
| return r; |
| |
| elapsed_usec = time_now - client->transaction_start; |
| if (elapsed_usec < 0xffff * USEC_PER_MSEC * 10) |
| elapsed_time = htobe16(elapsed_usec / USEC_PER_MSEC / 10); |
| else |
| elapsed_time = 0xffff; |
| |
| r = dhcp6_option_append(&opt, &optlen, SD_DHCP6_OPTION_ELAPSED_TIME, |
| sizeof(elapsed_time), &elapsed_time); |
| if (r < 0) |
| return r; |
| |
| r = dhcp6_network_send_udp_socket(client->fd, &all_servers, message, |
| len - optlen); |
| if (r < 0) |
| return r; |
| |
| log_dhcp6_client(client, "Sent %s", |
| dhcp6_message_type_to_string(message->type)); |
| |
| return 0; |
| } |
| |
| static int client_timeout_t2(sd_event_source *s, uint64_t usec, void *userdata) { |
| sd_dhcp6_client *client = userdata; |
| |
| assert(s); |
| assert(client); |
| assert(client->lease); |
| |
| client->lease->ia.timeout_t2 = |
| sd_event_source_unref(client->lease->ia.timeout_t2); |
| |
| log_dhcp6_client(client, "Timeout T2"); |
| |
| client_start(client, DHCP6_STATE_REBIND); |
| |
| return 0; |
| } |
| |
| static int client_timeout_t1(sd_event_source *s, uint64_t usec, void *userdata) { |
| sd_dhcp6_client *client = userdata; |
| |
| assert(s); |
| assert(client); |
| assert(client->lease); |
| |
| client->lease->ia.timeout_t1 = |
| sd_event_source_unref(client->lease->ia.timeout_t1); |
| |
| log_dhcp6_client(client, "Timeout T1"); |
| |
| client_start(client, DHCP6_STATE_RENEW); |
| |
| return 0; |
| } |
| |
| static int client_timeout_resend_expire(sd_event_source *s, uint64_t usec, void *userdata) { |
| sd_dhcp6_client *client = userdata; |
| DHCP6_CLIENT_DONT_DESTROY(client); |
| enum DHCP6State state; |
| |
| assert(s); |
| assert(client); |
| assert(client->event); |
| |
| state = client->state; |
| |
| client_stop(client, SD_DHCP6_CLIENT_EVENT_RESEND_EXPIRE); |
| |
| /* RFC 3315, section 18.1.4., says that "...the client may choose to |
| use a Solicit message to locate a new DHCP server..." */ |
| if (state == DHCP6_STATE_REBIND) |
| client_start(client, DHCP6_STATE_SOLICITATION); |
| |
| return 0; |
| } |
| |
| static usec_t client_timeout_compute_random(usec_t val) { |
| return val - val / 10 + |
| (random_u32() % (2 * USEC_PER_SEC)) * val / 10 / USEC_PER_SEC; |
| } |
| |
| static int client_timeout_resend(sd_event_source *s, uint64_t usec, void *userdata) { |
| int r = 0; |
| sd_dhcp6_client *client = userdata; |
| usec_t time_now, init_retransmit_time = 0, max_retransmit_time = 0; |
| usec_t max_retransmit_duration = 0; |
| uint8_t max_retransmit_count = 0; |
| char time_string[FORMAT_TIMESPAN_MAX]; |
| uint32_t expire = 0; |
| |
| assert(s); |
| assert(client); |
| assert(client->event); |
| |
| client->timeout_resend = sd_event_source_unref(client->timeout_resend); |
| |
| switch (client->state) { |
| case DHCP6_STATE_INFORMATION_REQUEST: |
| init_retransmit_time = DHCP6_INF_TIMEOUT; |
| max_retransmit_time = DHCP6_INF_MAX_RT; |
| |
| break; |
| |
| case DHCP6_STATE_SOLICITATION: |
| |
| if (client->retransmit_count && client->lease) { |
| client_start(client, DHCP6_STATE_REQUEST); |
| return 0; |
| } |
| |
| init_retransmit_time = DHCP6_SOL_TIMEOUT; |
| max_retransmit_time = DHCP6_SOL_MAX_RT; |
| |
| break; |
| |
| case DHCP6_STATE_REQUEST: |
| init_retransmit_time = DHCP6_REQ_TIMEOUT; |
| max_retransmit_time = DHCP6_REQ_MAX_RT; |
| max_retransmit_count = DHCP6_REQ_MAX_RC; |
| |
| break; |
| |
| case DHCP6_STATE_RENEW: |
| init_retransmit_time = DHCP6_REN_TIMEOUT; |
| max_retransmit_time = DHCP6_REN_MAX_RT; |
| |
| /* RFC 3315, section 18.1.3. says max retransmit duration will |
| be the remaining time until T2. Instead of setting MRD, |
| wait for T2 to trigger with the same end result */ |
| |
| break; |
| |
| case DHCP6_STATE_REBIND: |
| init_retransmit_time = DHCP6_REB_TIMEOUT; |
| max_retransmit_time = DHCP6_REB_MAX_RT; |
| |
| if (!client->timeout_resend_expire) { |
| r = dhcp6_lease_ia_rebind_expire(&client->lease->ia, |
| &expire); |
| if (r < 0) { |
| client_stop(client, r); |
| return 0; |
| } |
| max_retransmit_duration = expire * USEC_PER_SEC; |
| } |
| |
| break; |
| |
| case DHCP6_STATE_STOPPED: |
| case DHCP6_STATE_BOUND: |
| return 0; |
| } |
| |
| if (max_retransmit_count && |
| client->retransmit_count >= max_retransmit_count) { |
| client_stop(client, SD_DHCP6_CLIENT_EVENT_RETRANS_MAX); |
| return 0; |
| } |
| |
| r = sd_event_now(client->event, clock_boottime_or_monotonic(), &time_now); |
| if (r < 0) |
| goto error; |
| |
| r = client_send_message(client, time_now); |
| if (r >= 0) |
| client->retransmit_count++; |
| |
| if (!client->retransmit_time) { |
| client->retransmit_time = |
| client_timeout_compute_random(init_retransmit_time); |
| |
| if (client->state == DHCP6_STATE_SOLICITATION) |
| client->retransmit_time += init_retransmit_time / 10; |
| |
| } else { |
| if (max_retransmit_time && |
| client->retransmit_time > max_retransmit_time / 2) |
| client->retransmit_time = client_timeout_compute_random(max_retransmit_time); |
| else |
| client->retransmit_time += client_timeout_compute_random(client->retransmit_time); |
| } |
| |
| log_dhcp6_client(client, "Next retransmission in %s", |
| format_timespan(time_string, FORMAT_TIMESPAN_MAX, client->retransmit_time, USEC_PER_SEC)); |
| |
| r = sd_event_add_time(client->event, &client->timeout_resend, |
| clock_boottime_or_monotonic(), |
| time_now + client->retransmit_time, |
| 10 * USEC_PER_MSEC, client_timeout_resend, |
| client); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_priority(client->timeout_resend, |
| client->event_priority); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_description(client->timeout_resend, "dhcp6-resend-timer"); |
| if (r < 0) |
| goto error; |
| |
| if (max_retransmit_duration && !client->timeout_resend_expire) { |
| |
| log_dhcp6_client(client, "Max retransmission duration %"PRIu64" secs", |
| max_retransmit_duration / USEC_PER_SEC); |
| |
| r = sd_event_add_time(client->event, |
| &client->timeout_resend_expire, |
| clock_boottime_or_monotonic(), |
| time_now + max_retransmit_duration, |
| USEC_PER_SEC, |
| client_timeout_resend_expire, client); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_priority(client->timeout_resend_expire, |
| client->event_priority); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_description(client->timeout_resend_expire, "dhcp6-resend-expire-timer"); |
| if (r < 0) |
| goto error; |
| } |
| |
| error: |
| if (r < 0) |
| client_stop(client, r); |
| |
| return 0; |
| } |
| |
| static int client_ensure_iaid(sd_dhcp6_client *client) { |
| int r; |
| be32_t iaid; |
| |
| assert(client); |
| |
| if (client->ia_na.ia_na.id) |
| return 0; |
| |
| r = dhcp_identifier_set_iaid(client->ifindex, client->mac_addr, client->mac_addr_len, &iaid); |
| if (r < 0) |
| return r; |
| |
| client->ia_na.ia_na.id = iaid; |
| client->ia_pd.ia_pd.id = iaid; |
| |
| return 0; |
| } |
| |
| static int client_parse_message( |
| sd_dhcp6_client *client, |
| DHCP6Message *message, |
| size_t len, |
| sd_dhcp6_lease *lease) { |
| size_t pos = 0; |
| int r; |
| bool clientid = false; |
| uint32_t lt_t1 = ~0, lt_t2 = ~0; |
| |
| assert(client); |
| assert(message); |
| assert(len >= sizeof(DHCP6Message)); |
| assert(lease); |
| |
| len -= sizeof(DHCP6Message); |
| |
| while (pos < len) { |
| DHCP6Option *option = (DHCP6Option *)&message->options[pos]; |
| uint16_t optcode, optlen; |
| int status; |
| uint8_t *optval; |
| be32_t iaid_lease; |
| |
| if (len < offsetof(DHCP6Option, data) || |
| len < offsetof(DHCP6Option, data) + be16toh(option->len)) |
| return -ENOBUFS; |
| |
| optcode = be16toh(option->code); |
| optlen = be16toh(option->len); |
| optval = option->data; |
| |
| switch (optcode) { |
| case SD_DHCP6_OPTION_CLIENTID: |
| if (clientid) { |
| log_dhcp6_client(client, "%s contains multiple clientids", |
| dhcp6_message_type_to_string(message->type)); |
| return -EINVAL; |
| } |
| |
| if (optlen != client->duid_len || |
| memcmp(&client->duid, optval, optlen) != 0) { |
| log_dhcp6_client(client, "%s DUID does not match", |
| dhcp6_message_type_to_string(message->type)); |
| |
| return -EINVAL; |
| } |
| clientid = true; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_SERVERID: |
| r = dhcp6_lease_get_serverid(lease, NULL, NULL); |
| if (r >= 0) { |
| log_dhcp6_client(client, "%s contains multiple serverids", |
| dhcp6_message_type_to_string(message->type)); |
| return -EINVAL; |
| } |
| |
| r = dhcp6_lease_set_serverid(lease, optval, optlen); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_PREFERENCE: |
| if (optlen != 1) |
| return -EINVAL; |
| |
| r = dhcp6_lease_set_preference(lease, optval[0]); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_STATUS_CODE: |
| status = dhcp6_option_parse_status(option); |
| if (status) { |
| log_dhcp6_client(client, "%s Status %s", |
| dhcp6_message_type_to_string(message->type), |
| dhcp6_message_status_to_string(status)); |
| dhcp6_lease_free_ia(&lease->ia); |
| dhcp6_lease_free_ia(&lease->pd); |
| |
| return -EINVAL; |
| } |
| |
| break; |
| |
| case SD_DHCP6_OPTION_IA_NA: |
| if (client->state == DHCP6_STATE_INFORMATION_REQUEST) { |
| log_dhcp6_client(client, "Information request ignoring IA NA option"); |
| |
| break; |
| } |
| |
| r = dhcp6_option_parse_ia(option, &lease->ia); |
| if (r < 0 && r != -ENOMSG) |
| return r; |
| |
| r = dhcp6_lease_get_iaid(lease, &iaid_lease); |
| if (r < 0) |
| return r; |
| |
| if (client->ia_na.ia_na.id != iaid_lease) { |
| log_dhcp6_client(client, "%s has wrong IAID for IA NA", |
| dhcp6_message_type_to_string(message->type)); |
| return -EINVAL; |
| } |
| |
| if (lease->ia.addresses) { |
| lt_t1 = MIN(lt_t1, be32toh(lease->ia.ia_na.lifetime_t1)); |
| lt_t2 = MIN(lt_t2, be32toh(lease->ia.ia_na.lifetime_t1)); |
| } |
| |
| break; |
| |
| case SD_DHCP6_OPTION_IA_PD: |
| if (client->state == DHCP6_STATE_INFORMATION_REQUEST) { |
| log_dhcp6_client(client, "Information request ignoring IA PD option"); |
| |
| break; |
| } |
| |
| r = dhcp6_option_parse_ia(option, &lease->pd); |
| if (r < 0 && r != -ENOMSG) |
| return r; |
| |
| r = dhcp6_lease_get_iaid(lease, &iaid_lease); |
| if (r < 0) |
| return r; |
| |
| if (client->ia_pd.ia_pd.id != iaid_lease) { |
| log_dhcp6_client(client, "%s has wrong IAID for IA PD", |
| dhcp6_message_type_to_string(message->type)); |
| return -EINVAL; |
| } |
| |
| if (lease->pd.addresses) { |
| lt_t1 = MIN(lt_t1, be32toh(lease->pd.ia_pd.lifetime_t1)); |
| lt_t2 = MIN(lt_t2, be32toh(lease->pd.ia_pd.lifetime_t2)); |
| } |
| |
| break; |
| |
| case SD_DHCP6_OPTION_RAPID_COMMIT: |
| r = dhcp6_lease_set_rapid_commit(lease); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_DNS_SERVERS: |
| r = dhcp6_lease_set_dns(lease, optval, optlen); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_DOMAIN_LIST: |
| r = dhcp6_lease_set_domains(lease, optval, optlen); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_NTP_SERVER: |
| r = dhcp6_lease_set_ntp(lease, optval, optlen); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case SD_DHCP6_OPTION_SNTP_SERVERS: |
| r = dhcp6_lease_set_sntp(lease, optval, optlen); |
| if (r < 0) |
| return r; |
| |
| break; |
| } |
| |
| pos += sizeof(*option) + optlen; |
| } |
| |
| if (!clientid) { |
| log_dhcp6_client(client, "%s has incomplete options", |
| dhcp6_message_type_to_string(message->type)); |
| return -EINVAL; |
| } |
| |
| if (client->state != DHCP6_STATE_INFORMATION_REQUEST) { |
| r = dhcp6_lease_get_serverid(lease, NULL, NULL); |
| if (r < 0) { |
| log_dhcp6_client(client, "%s has no server id", |
| dhcp6_message_type_to_string(message->type)); |
| return -EINVAL; |
| } |
| |
| } else { |
| if (lease->ia.addresses) { |
| lease->ia.ia_na.lifetime_t1 = htobe32(lt_t1); |
| lease->ia.ia_na.lifetime_t2 = htobe32(lt_t2); |
| } |
| |
| if (lease->pd.addresses) { |
| lease->pd.ia_pd.lifetime_t1 = htobe32(lt_t1); |
| lease->pd.ia_pd.lifetime_t2 = htobe32(lt_t2); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int client_receive_reply(sd_dhcp6_client *client, DHCP6Message *reply, size_t len) { |
| _cleanup_(sd_dhcp6_lease_unrefp) sd_dhcp6_lease *lease = NULL; |
| bool rapid_commit; |
| int r; |
| |
| assert(client); |
| assert(reply); |
| |
| if (reply->type != DHCP6_REPLY) |
| return 0; |
| |
| r = dhcp6_lease_new(&lease); |
| if (r < 0) |
| return -ENOMEM; |
| |
| r = client_parse_message(client, reply, len, lease); |
| if (r < 0) |
| return r; |
| |
| if (client->state == DHCP6_STATE_SOLICITATION) { |
| r = dhcp6_lease_get_rapid_commit(lease, &rapid_commit); |
| if (r < 0) |
| return r; |
| |
| if (!rapid_commit) |
| return 0; |
| } |
| |
| client_set_lease(client, lease); |
| lease = NULL; |
| |
| return DHCP6_STATE_BOUND; |
| } |
| |
| static int client_receive_advertise(sd_dhcp6_client *client, DHCP6Message *advertise, size_t len) { |
| _cleanup_(sd_dhcp6_lease_unrefp) sd_dhcp6_lease *lease = NULL; |
| uint8_t pref_advertise = 0, pref_lease = 0; |
| int r; |
| |
| if (advertise->type != DHCP6_ADVERTISE) |
| return 0; |
| |
| r = dhcp6_lease_new(&lease); |
| if (r < 0) |
| return r; |
| |
| r = client_parse_message(client, advertise, len, lease); |
| if (r < 0) |
| return r; |
| |
| r = dhcp6_lease_get_preference(lease, &pref_advertise); |
| if (r < 0) |
| return r; |
| |
| r = dhcp6_lease_get_preference(client->lease, &pref_lease); |
| |
| if (r < 0 || pref_advertise > pref_lease) { |
| client_set_lease(client, lease); |
| lease = NULL; |
| r = 0; |
| } |
| |
| if (pref_advertise == 255 || client->retransmit_count > 1) |
| r = DHCP6_STATE_REQUEST; |
| |
| return r; |
| } |
| |
| static int client_receive_message( |
| sd_event_source *s, |
| int fd, uint32_t |
| revents, |
| void *userdata) { |
| |
| sd_dhcp6_client *client = userdata; |
| DHCP6_CLIENT_DONT_DESTROY(client); |
| _cleanup_free_ DHCP6Message *message = NULL; |
| ssize_t buflen, len; |
| int r = 0; |
| |
| assert(s); |
| assert(client); |
| assert(client->event); |
| |
| buflen = next_datagram_size_fd(fd); |
| if (buflen < 0) |
| return buflen; |
| |
| message = malloc(buflen); |
| if (!message) |
| return -ENOMEM; |
| |
| len = recv(fd, message, buflen, 0); |
| if (len < 0) { |
| if (IN_SET(errno, EAGAIN, EINTR)) |
| return 0; |
| |
| return log_dhcp6_client_errno(client, errno, "Could not receive message from UDP socket: %m"); |
| |
| } |
| if ((size_t) len < sizeof(DHCP6Message)) { |
| log_dhcp6_client(client, "Too small to be DHCP6 message: ignoring"); |
| return 0; |
| } |
| |
| switch(message->type) { |
| case DHCP6_SOLICIT: |
| case DHCP6_REQUEST: |
| case DHCP6_CONFIRM: |
| case DHCP6_RENEW: |
| case DHCP6_REBIND: |
| case DHCP6_RELEASE: |
| case DHCP6_DECLINE: |
| case DHCP6_INFORMATION_REQUEST: |
| case DHCP6_RELAY_FORW: |
| case DHCP6_RELAY_REPL: |
| return 0; |
| |
| case DHCP6_ADVERTISE: |
| case DHCP6_REPLY: |
| case DHCP6_RECONFIGURE: |
| break; |
| |
| default: |
| log_dhcp6_client(client, "Unknown message type %d", message->type); |
| return 0; |
| } |
| |
| if (client->transaction_id != (message->transaction_id & |
| htobe32(0x00ffffff))) |
| return 0; |
| |
| switch (client->state) { |
| case DHCP6_STATE_INFORMATION_REQUEST: |
| r = client_receive_reply(client, message, len); |
| if (r < 0) |
| return 0; |
| |
| client_notify(client, SD_DHCP6_CLIENT_EVENT_INFORMATION_REQUEST); |
| |
| client_start(client, DHCP6_STATE_STOPPED); |
| |
| break; |
| |
| case DHCP6_STATE_SOLICITATION: |
| r = client_receive_advertise(client, message, len); |
| |
| if (r == DHCP6_STATE_REQUEST) { |
| client_start(client, r); |
| |
| break; |
| } |
| |
| _fallthrough_; /* for Soliciation Rapid Commit option check */ |
| case DHCP6_STATE_REQUEST: |
| case DHCP6_STATE_RENEW: |
| case DHCP6_STATE_REBIND: |
| |
| r = client_receive_reply(client, message, len); |
| if (r < 0) |
| return 0; |
| |
| if (r == DHCP6_STATE_BOUND) { |
| |
| r = client_start(client, DHCP6_STATE_BOUND); |
| if (r < 0) { |
| client_stop(client, r); |
| return 0; |
| } |
| |
| client_notify(client, SD_DHCP6_CLIENT_EVENT_IP_ACQUIRE); |
| } |
| |
| break; |
| |
| case DHCP6_STATE_BOUND: |
| |
| break; |
| |
| case DHCP6_STATE_STOPPED: |
| return 0; |
| } |
| |
| if (r >= 0) |
| log_dhcp6_client(client, "Recv %s", |
| dhcp6_message_type_to_string(message->type)); |
| |
| return 0; |
| } |
| |
| static int client_start(sd_dhcp6_client *client, enum DHCP6State state) { |
| int r; |
| usec_t timeout, time_now; |
| char time_string[FORMAT_TIMESPAN_MAX]; |
| |
| assert_return(client, -EINVAL); |
| assert_return(client->event, -EINVAL); |
| assert_return(client->ifindex > 0, -EINVAL); |
| assert_return(client->state != state, -EINVAL); |
| |
| client->timeout_resend_expire = |
| sd_event_source_unref(client->timeout_resend_expire); |
| client->timeout_resend = sd_event_source_unref(client->timeout_resend); |
| client->retransmit_time = 0; |
| client->retransmit_count = 0; |
| |
| r = sd_event_now(client->event, clock_boottime_or_monotonic(), &time_now); |
| if (r < 0) |
| return r; |
| |
| if (!client->receive_message) { |
| r = sd_event_add_io(client->event, &client->receive_message, |
| client->fd, EPOLLIN, client_receive_message, |
| client); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_priority(client->receive_message, |
| client->event_priority); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_description(client->receive_message, |
| "dhcp6-receive-message"); |
| if (r < 0) |
| goto error; |
| } |
| |
| switch (state) { |
| case DHCP6_STATE_STOPPED: |
| if (client->state == DHCP6_STATE_INFORMATION_REQUEST) { |
| client->state = DHCP6_STATE_STOPPED; |
| |
| return 0; |
| } |
| |
| _fallthrough_; |
| case DHCP6_STATE_SOLICITATION: |
| client->state = DHCP6_STATE_SOLICITATION; |
| |
| break; |
| |
| case DHCP6_STATE_INFORMATION_REQUEST: |
| case DHCP6_STATE_REQUEST: |
| case DHCP6_STATE_RENEW: |
| case DHCP6_STATE_REBIND: |
| |
| client->state = state; |
| |
| break; |
| |
| case DHCP6_STATE_BOUND: |
| |
| if (client->lease->ia.ia_na.lifetime_t1 == 0xffffffff || |
| client->lease->ia.ia_na.lifetime_t2 == 0xffffffff) { |
| |
| log_dhcp6_client(client, "Infinite T1 0x%08x or T2 0x%08x", |
| be32toh(client->lease->ia.ia_na.lifetime_t1), |
| be32toh(client->lease->ia.ia_na.lifetime_t2)); |
| |
| return 0; |
| } |
| |
| timeout = client_timeout_compute_random(be32toh(client->lease->ia.ia_na.lifetime_t1) * USEC_PER_SEC); |
| |
| log_dhcp6_client(client, "T1 expires in %s", |
| format_timespan(time_string, FORMAT_TIMESPAN_MAX, timeout, USEC_PER_SEC)); |
| |
| r = sd_event_add_time(client->event, |
| &client->lease->ia.timeout_t1, |
| clock_boottime_or_monotonic(), time_now + timeout, |
| 10 * USEC_PER_SEC, client_timeout_t1, |
| client); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_priority(client->lease->ia.timeout_t1, |
| client->event_priority); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_description(client->lease->ia.timeout_t1, "dhcp6-t1-timeout"); |
| if (r < 0) |
| goto error; |
| |
| timeout = client_timeout_compute_random(be32toh(client->lease->ia.ia_na.lifetime_t2) * USEC_PER_SEC); |
| |
| log_dhcp6_client(client, "T2 expires in %s", |
| format_timespan(time_string, FORMAT_TIMESPAN_MAX, timeout, USEC_PER_SEC)); |
| |
| r = sd_event_add_time(client->event, |
| &client->lease->ia.timeout_t2, |
| clock_boottime_or_monotonic(), time_now + timeout, |
| 10 * USEC_PER_SEC, client_timeout_t2, |
| client); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_priority(client->lease->ia.timeout_t2, |
| client->event_priority); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_description(client->lease->ia.timeout_t2, "dhcp6-t2-timeout"); |
| if (r < 0) |
| goto error; |
| |
| client->state = state; |
| |
| return 0; |
| } |
| |
| client->transaction_id = random_u32() & htobe32(0x00ffffff); |
| client->transaction_start = time_now; |
| |
| r = sd_event_add_time(client->event, &client->timeout_resend, |
| clock_boottime_or_monotonic(), 0, 0, client_timeout_resend, |
| client); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_priority(client->timeout_resend, |
| client->event_priority); |
| if (r < 0) |
| goto error; |
| |
| r = sd_event_source_set_description(client->timeout_resend, "dhcp6-resend-timeout"); |
| if (r < 0) |
| goto error; |
| |
| return 0; |
| |
| error: |
| client_reset(client); |
| return r; |
| } |
| |
| int sd_dhcp6_client_stop(sd_dhcp6_client *client) { |
| assert_return(client, -EINVAL); |
| |
| client_stop(client, SD_DHCP6_CLIENT_EVENT_STOP); |
| |
| client->fd = safe_close(client->fd); |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_is_running(sd_dhcp6_client *client) { |
| assert_return(client, -EINVAL); |
| |
| return client->state != DHCP6_STATE_STOPPED; |
| } |
| |
| int sd_dhcp6_client_start(sd_dhcp6_client *client) { |
| enum DHCP6State state = DHCP6_STATE_SOLICITATION; |
| int r = 0; |
| |
| assert_return(client, -EINVAL); |
| assert_return(client->event, -EINVAL); |
| assert_return(client->ifindex > 0, -EINVAL); |
| assert_return(in_addr_is_link_local(AF_INET6, (const union in_addr_union *) &client->local_address) > 0, -EINVAL); |
| |
| if (!IN_SET(client->state, DHCP6_STATE_STOPPED)) |
| return -EBUSY; |
| |
| r = client_reset(client); |
| if (r < 0) |
| return r; |
| |
| r = client_ensure_iaid(client); |
| if (r < 0) |
| return r; |
| |
| r = client_ensure_duid(client); |
| if (r < 0) |
| return r; |
| |
| if (client->fd < 0) { |
| r = dhcp6_network_bind_udp_socket(client->ifindex, &client->local_address); |
| if (r < 0) { |
| _cleanup_free_ char *p = NULL; |
| |
| (void) in_addr_to_string(AF_INET6, (const union in_addr_union*) &client->local_address, &p); |
| return log_dhcp6_client_errno(client, r, |
| "Failed to bind to UDP socket at address %s: %m", strna(p)); |
| } |
| |
| client->fd = r; |
| } |
| |
| if (client->information_request) |
| state = DHCP6_STATE_INFORMATION_REQUEST; |
| |
| log_dhcp6_client(client, "Started in %s mode", |
| client->information_request? "Information request": |
| "Managed"); |
| |
| return client_start(client, state); |
| } |
| |
| int sd_dhcp6_client_attach_event(sd_dhcp6_client *client, sd_event *event, int64_t priority) { |
| int r; |
| |
| assert_return(client, -EINVAL); |
| assert_return(!client->event, -EBUSY); |
| |
| if (event) |
| client->event = sd_event_ref(event); |
| else { |
| r = sd_event_default(&client->event); |
| if (r < 0) |
| return 0; |
| } |
| |
| client->event_priority = priority; |
| |
| return 0; |
| } |
| |
| int sd_dhcp6_client_detach_event(sd_dhcp6_client *client) { |
| assert_return(client, -EINVAL); |
| |
| client->event = sd_event_unref(client->event); |
| |
| return 0; |
| } |
| |
| sd_event *sd_dhcp6_client_get_event(sd_dhcp6_client *client) { |
| assert_return(client, NULL); |
| |
| return client->event; |
| } |
| |
| sd_dhcp6_client *sd_dhcp6_client_ref(sd_dhcp6_client *client) { |
| |
| if (!client) |
| return NULL; |
| |
| assert(client->n_ref >= 1); |
| client->n_ref++; |
| |
| return client; |
| } |
| |
| sd_dhcp6_client *sd_dhcp6_client_unref(sd_dhcp6_client *client) { |
| |
| if (!client) |
| return NULL; |
| |
| assert(client->n_ref >= 1); |
| client->n_ref--; |
| |
| if (client->n_ref > 0) |
| return NULL; |
| |
| client_reset(client); |
| |
| client->fd = safe_close(client->fd); |
| |
| sd_dhcp6_client_detach_event(client); |
| |
| free(client->req_opts); |
| free(client->fqdn); |
| return mfree(client); |
| } |
| |
| int sd_dhcp6_client_new(sd_dhcp6_client **ret) { |
| _cleanup_(sd_dhcp6_client_unrefp) sd_dhcp6_client *client = NULL; |
| size_t t; |
| |
| assert_return(ret, -EINVAL); |
| |
| client = new0(sd_dhcp6_client, 1); |
| if (!client) |
| return -ENOMEM; |
| |
| client->n_ref = 1; |
| client->ia_na.type = SD_DHCP6_OPTION_IA_NA; |
| client->ia_pd.type = SD_DHCP6_OPTION_IA_PD; |
| client->ifindex = -1; |
| client->fd = -1; |
| |
| client->req_opts_len = ELEMENTSOF(default_req_opts); |
| client->req_opts = new0(be16_t, client->req_opts_len); |
| if (!client->req_opts) |
| return -ENOMEM; |
| |
| for (t = 0; t < client->req_opts_len; t++) |
| client->req_opts[t] = htobe16(default_req_opts[t]); |
| |
| *ret = client; |
| client = NULL; |
| |
| return 0; |
| } |