diff options
| -rw-r--r-- | src/libsystemd-network/dhcp-protocol.h | 10 | ||||
| -rw-r--r-- | src/libsystemd-network/sd-dhcp-client.c | 53 |
2 files changed, 54 insertions, 9 deletions
diff --git a/src/libsystemd-network/dhcp-protocol.h b/src/libsystemd-network/dhcp-protocol.h index 88a81d2866..5cf4e9e306 100644 --- a/src/libsystemd-network/dhcp-protocol.h +++ b/src/libsystemd-network/dhcp-protocol.h @@ -137,6 +137,7 @@ enum { DHCP_OPTION_REBINDING_T2_TIME = 59, DHCP_OPTION_VENDOR_CLASS_IDENTIFIER = 60, DHCP_OPTION_CLIENT_IDENTIFIER = 61, + DHCP_OPTION_FQDN = 81, DHCP_OPTION_NEW_POSIX_TIMEZONE = 100, DHCP_OPTION_NEW_TZDB_TIMEZONE = 101, DHCP_OPTION_CLASSLESS_STATIC_ROUTE = 121, @@ -144,3 +145,12 @@ enum { DHCP_OPTION_PRIVATE_LAST = 254, DHCP_OPTION_END = 255, }; + +#define DHCP_MAX_FQDN_LENGTH 255 + +enum { + DHCP_FQDN_FLAG_S = (1 << 0), + DHCP_FQDN_FLAG_O = (1 << 1), + DHCP_FQDN_FLAG_E = (1 << 2), + DHCP_FQDN_FLAG_N = (1 << 3), +}; diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c index 137537253a..5ec0e661f7 100644 --- a/src/libsystemd-network/sd-dhcp-client.c +++ b/src/libsystemd-network/sd-dhcp-client.c @@ -34,6 +34,8 @@ #include "dhcp-internal.h" #include "dhcp-lease-internal.h" #include "dhcp-protocol.h" +#include "dns-domain.h" +#include "hostname-util.h" #include "random-util.h" #include "string-util.h" #include "util.h" @@ -298,6 +300,9 @@ int sd_dhcp_client_set_hostname(sd_dhcp_client *client, assert_return(client, -EINVAL); + if (!hostname_is_valid(hostname, false) && !dns_name_is_valid(hostname)) + return -EINVAL; + if (streq_ptr(client->hostname, hostname)) return 0; @@ -539,6 +544,24 @@ static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret, return 0; } +static int client_append_fqdn_option(DHCPMessage *message, size_t optlen, size_t *optoffset, + const char *fqdn) { + uint8_t buffer[3 + DHCP_MAX_FQDN_LENGTH]; + int r; + + buffer[0] = DHCP_FQDN_FLAG_S | /* Request server to perform A RR DNS updates */ + DHCP_FQDN_FLAG_E; /* Canonical wire format */ + buffer[1] = 0; /* RCODE1 (deprecated) */ + buffer[2] = 0; /* RCODE2 (deprecated) */ + + r = dns_name_to_wire_format(fqdn, buffer + 3, sizeof(buffer) - 3); + if (r > 0) + r = dhcp_option_append(message, optlen, optoffset, 0, + DHCP_OPTION_FQDN, 3 + r, buffer); + + return r; +} + static int dhcp_client_send_raw(sd_dhcp_client *client, DHCPPacket *packet, size_t len) { dhcp_packet_append_ip_headers(packet, INADDR_ANY, DHCP_PORT_CLIENT, @@ -576,13 +599,21 @@ static int client_send_discover(sd_dhcp_client *client) { return r; } - /* it is unclear from RFC 2131 if client should send hostname in - DHCPDISCOVER but dhclient does and so we do as well - */ if (client->hostname) { - r = dhcp_option_append(&discover->dhcp, optlen, &optoffset, 0, - DHCP_OPTION_HOST_NAME, - strlen(client->hostname), client->hostname); + /* According to RFC 4702 "clients that send the Client FQDN option in + their messages MUST NOT also send the Host Name option". Just send + one of the two depending on the hostname type. + */ + if (dns_name_single_label(client->hostname)) { + /* it is unclear from RFC 2131 if client should send hostname in + DHCPDISCOVER but dhclient does and so we do as well + */ + r = dhcp_option_append(&discover->dhcp, optlen, &optoffset, 0, + DHCP_OPTION_HOST_NAME, + strlen(client->hostname), client->hostname); + } else + r = client_append_fqdn_option(&discover->dhcp, optlen, &optoffset, + client->hostname); if (r < 0) return r; } @@ -688,9 +719,13 @@ static int client_send_request(sd_dhcp_client *client) { } if (client->hostname) { - r = dhcp_option_append(&request->dhcp, optlen, &optoffset, 0, - DHCP_OPTION_HOST_NAME, - strlen(client->hostname), client->hostname); + if (dns_name_single_label(client->hostname)) + r = dhcp_option_append(&request->dhcp, optlen, &optoffset, 0, + DHCP_OPTION_HOST_NAME, + strlen(client->hostname), client->hostname); + else + r = client_append_fqdn_option(&request->dhcp, optlen, &optoffset, + client->hostname); if (r < 0) return r; } |