X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibsystemd-network%2Fsd-dhcp-client.c;h=c8a724f27e00c0817c84f185c47aa6af5ac3f8c0;hp=689163cffe5bed7920714d18681e150f23f5ed02;hb=f131770b1465fbf423881f16ba85523a05f846fe;hpb=356779df90a2ecab5da2cb310ad0f8ebc9ca9f46 diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c index 689163cff..c8a724f27 100644 --- a/src/libsystemd-network/sd-dhcp-client.c +++ b/src/libsystemd-network/sd-dhcp-client.c @@ -38,6 +38,7 @@ #include "dhcp-lease-internal.h" #include "sd-dhcp-client.h" +#define MAX_CLIENT_ID_LEN 64 /* Arbitrary limit */ #define MAX_MAC_ADDR_LEN INFINIBAND_ALEN struct sd_dhcp_client { @@ -56,19 +57,38 @@ struct sd_dhcp_client { size_t req_opts_allocated; size_t req_opts_size; be32_t last_addr; - struct { - uint8_t type; - struct ether_addr mac_addr; - } _packed_ client_id; uint8_t mac_addr[MAX_MAC_ADDR_LEN]; size_t mac_addr_len; uint16_t arp_type; + union { + struct { + uint8_t type; /* 0: Generic (non-LL) (RFC 2132) */ + uint8_t data[MAX_CLIENT_ID_LEN]; + } _packed_ gen; + struct { + uint8_t type; /* 1: Ethernet Link-Layer (RFC 2132) */ + uint8_t haddr[ETH_ALEN]; + } _packed_ eth; + struct { + uint8_t type; /* 2 - 254: ARP/Link-Layer (RFC 2132) */ + uint8_t haddr[0]; + } _packed_ ll; + struct { + uint8_t type; /* 255: Node-specific (RFC 4361) */ + uint8_t iaid[4]; + uint8_t duid[MAX_CLIENT_ID_LEN - 4]; + } _packed_ ns; + struct { + uint8_t type; + uint8_t data[MAX_CLIENT_ID_LEN]; + } _packed_ raw; + } client_id; + size_t client_id_len; char *hostname; char *vendor_class_identifier; uint32_t mtu; uint32_t xid; usec_t start_time; - uint16_t secs; unsigned int attempt; usec_t request_sent; sd_event_source *timeout_t1; @@ -201,8 +221,70 @@ int sd_dhcp_client_set_mac(sd_dhcp_client *client, const uint8_t *addr, client->mac_addr_len = addr_len; client->arp_type = arp_type; - memcpy(&client->client_id.mac_addr, addr, ETH_ALEN); - client->client_id.type = 0x01; + if (need_restart && client->state != DHCP_STATE_STOPPED) + sd_dhcp_client_start(client); + + return 0; +} + +int sd_dhcp_client_get_client_id(sd_dhcp_client *client, uint8_t *type, + const uint8_t **data, size_t *data_len) { + + assert_return(client, -EINVAL); + assert_return(type, -EINVAL); + assert_return(data, -EINVAL); + assert_return(data_len, -EINVAL); + + *type = 0; + *data = NULL; + *data_len = 0; + if (client->client_id_len) { + *type = client->client_id.raw.type; + *data = client->client_id.raw.data; + *data_len = client->client_id_len - + sizeof (client->client_id.raw.type); + } + + return 0; +} + +int sd_dhcp_client_set_client_id(sd_dhcp_client *client, uint8_t type, + const uint8_t *data, size_t data_len) { + DHCP_CLIENT_DONT_DESTROY(client); + bool need_restart = false; + + assert_return(client, -EINVAL); + assert_return(data, -EINVAL); + assert_return(data_len > 0 && data_len <= MAX_CLIENT_ID_LEN, -EINVAL); + + switch (type) { + case ARPHRD_ETHER: + if (data_len != ETH_ALEN) + return -EINVAL; + break; + case ARPHRD_INFINIBAND: + if (data_len != INFINIBAND_ALEN) + return -EINVAL; + break; + default: + break; + } + + if (client->client_id_len == data_len + sizeof (client->client_id.raw.type) && + client->client_id.raw.type == type && + memcmp(&client->client_id.raw.data, data, data_len) == 0) + return 0; + + if (!IN_SET(client->state, DHCP_STATE_INIT, DHCP_STATE_STOPPED)) { + log_dhcp_client(client, "Changing client ID on running DHCP " + "client, restarting"); + need_restart = true; + client_stop(client, DHCP_EVENT_STOP); + } + + client->client_id.raw.type = type; + memcpy(&client->client_id.raw.data, data, data_len); + client->client_id_len = data_len + sizeof (client->client_id.raw.type); if (need_restart && client->state != DHCP_STATE_STOPPED) sd_dhcp_client_start(client); @@ -321,10 +403,12 @@ static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret, _cleanup_free_ DHCPPacket *packet; size_t optlen, optoffset, size; be16_t max_size; + usec_t time_now; + uint16_t secs; int r; assert(client); - assert(client->secs); + assert(client->start_time); assert(ret); assert(_optlen); assert(_optoffset); @@ -344,7 +428,15 @@ static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret, /* Although 'secs' field is a SHOULD in RFC 2131, certain DHCP servers refuse to issue an DHCP lease if 'secs' is set to zero */ - packet->dhcp.secs = htobe16(client->secs); + r = sd_event_now(client->event, clock_boottime_or_monotonic(), &time_now); + if (r < 0) + return r; + assert(time_now >= client->start_time); + + /* seconds between sending first and last DISCOVER + * must always be strictly positive to deal with broken servers */ + secs = ((time_now - client->start_time) / USEC_PER_SEC) ? : 1; + packet->dhcp.secs = htobe16(secs); /* RFC2132 section 4.1 A client that cannot receive unicast IP datagrams until its protocol @@ -369,14 +461,24 @@ static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret, if (client->arp_type == ARPHRD_ETHER) memcpy(&packet->dhcp.chaddr, &client->mac_addr, ETH_ALEN); + /* If no client identifier exists, construct one from an ethernet + address if present */ + if (client->client_id_len == 0 && client->arp_type == ARPHRD_ETHER) { + client->client_id.eth.type = ARPHRD_ETHER; + memcpy(&client->client_id.eth.haddr, &client->mac_addr, ETH_ALEN); + client->client_id_len = sizeof (client->client_id.eth); + } + /* Some DHCP servers will refuse to issue an DHCP lease if the Client Identifier option is not set */ - r = dhcp_option_append(&packet->dhcp, optlen, &optoffset, 0, - DHCP_OPTION_CLIENT_IDENTIFIER, - sizeof(client->client_id), &client->client_id); - if (r < 0) - return r; - + if (client->client_id_len) { + r = dhcp_option_append(&packet->dhcp, optlen, &optoffset, 0, + DHCP_OPTION_CLIENT_IDENTIFIER, + client->client_id_len, + &client->client_id.raw); + if (r < 0) + return r; + } /* RFC2131 section 3.5: in its initial DHCPDISCOVER or DHCPREQUEST message, a @@ -398,7 +500,7 @@ static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret, Note (from ConnMan): Some DHCP servers will send bigger DHCP packets than the defined default size unless the Maximum Messge Size option - is explicitely set + is explicitly set RFC3442 "Requirements to Avoid Sizing Constraints": Because a full routing table can be quite large, the standard 576 @@ -441,24 +543,12 @@ static int dhcp_client_send_raw(sd_dhcp_client *client, DHCPPacket *packet, static int client_send_discover(sd_dhcp_client *client) { _cleanup_free_ DHCPPacket *discover = NULL; size_t optoffset, optlen; - usec_t time_now; int r; assert(client); assert(client->state == DHCP_STATE_INIT || client->state == DHCP_STATE_SELECTING); - /* See RFC2131 section 4.4.1 */ - - r = sd_event_now(client->event, clock_boottime_or_monotonic(), &time_now); - if (r < 0) - return r; - assert(time_now >= client->start_time); - - /* seconds between sending first and last DISCOVER - * must always be strictly positive to deal with broken servers */ - client->secs = ((time_now - client->start_time) / USEC_PER_SEC) ? : 1; - r = client_message_init(client, &discover, DHCP_DISCOVER, &optlen, &optoffset); if (r < 0) @@ -872,10 +962,8 @@ static int client_start(sd_dhcp_client *client) { } client->fd = r; - if (client->state == DHCP_STATE_INIT) { + if (client->state == DHCP_STATE_INIT || client->state == DHCP_STATE_INIT_REBOOT) client->start_time = now(clock_boottime_or_monotonic()); - client->secs = 0; - } return client_initialize_events(client, client_receive_message_raw); } @@ -941,6 +1029,14 @@ static int client_handle_offer(sd_dhcp_client *client, DHCPMessage *offer, if (r < 0) return r; + if (client->client_id_len) { + r = dhcp_lease_set_client_id(lease, + (uint8_t *) &client->client_id.raw, + client->client_id_len); + if (r < 0) + return r; + } + r = dhcp_option_parse(offer, len, dhcp_lease_parse_options, lease); if (r != DHCP_OFFER) { log_dhcp_client(client, "received message was not an OFFER, ignoring"); @@ -1000,6 +1096,14 @@ static int client_handle_ack(sd_dhcp_client *client, DHCPMessage *ack, if (r < 0) return r; + if (client->client_id_len) { + r = dhcp_lease_set_client_id(lease, + (uint8_t *) &client->client_id.raw, + client->client_id_len); + if (r < 0) + return r; + } + r = dhcp_option_parse(ack, len, dhcp_lease_parse_options, lease); if (r == DHCP_NAK) { log_dhcp_client(client, "NAK"); @@ -1278,8 +1382,10 @@ static int client_handle_message(sd_dhcp_client *client, DHCPMessage *message, client->last_addr = client->lease->address; r = client_set_lease_timeouts(client); - if (r < 0) + if (r < 0) { + log_dhcp_client(client, "could not set lease timeouts"); goto error; + } r = dhcp_network_bind_udp_socket(client->lease->address, DHCP_PORT_CLIENT);