From f5a70de7a9a9e8a37ba96f89ad75fcc31336bfa3 Mon Sep 17 00:00:00 2001 From: Patrik Flykt Date: Mon, 9 Dec 2013 23:43:22 +0200 Subject: [PATCH] dhcp: Support seconds elapsed since start of DHCP negotiation It was noticed by Grant Erickson in ConnMan commit 95e15c09350acf58d4707056ae2614570883ef66 that: "Certain DHCP servers, such as that implemented in Mac OS X (< 10.7) for its "Internet Sharing" feature, refuse to issue a DHCP lease to clients that have not set a non-zero value in their DISCOVER or REQUEST packets." --- src/libsystemd-dhcp/dhcp-client.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/src/libsystemd-dhcp/dhcp-client.c b/src/libsystemd-dhcp/dhcp-client.c index 4d1722f5b..181c6f834 100644 --- a/src/libsystemd-dhcp/dhcp-client.c +++ b/src/libsystemd-dhcp/dhcp-client.c @@ -120,8 +120,8 @@ int sd_dhcp_client_set_mac(sd_dhcp_client *client, } static int client_packet_init(sd_dhcp_client *client, uint8_t type, - DHCPMessage *message, uint8_t **opt, - size_t *optlen) + DHCPMessage *message, uint16_t secs, + uint8_t **opt, size_t *optlen) { int err; @@ -136,6 +136,10 @@ static int client_packet_init(sd_dhcp_client *client, uint8_t type, message->hlen = ETHER_ADDR_LEN; message->xid = htobe32(client->xid); + /* Although 'secs' field is a SHOULD in RFC 2131, certain DHCP servers + refuse to issue an DHCP lease if 'secs' is set to zero */ + message->secs = htobe16(secs); + memcpy(&message->chaddr, &client->mac_addr, ETH_ALEN); (*opt)[0] = 0x63; (*opt)[1] = 0x82; @@ -189,7 +193,7 @@ static uint16_t client_checksum(void *buf, int len) return ~((sum & 0xffff) + (sum >> 16)); } -static int client_send_discover(sd_dhcp_client *client) +static int client_send_discover(sd_dhcp_client *client, uint16_t secs) { int err = 0; _cleanup_free_ DHCPPacket *discover; @@ -205,7 +209,7 @@ static int client_send_discover(sd_dhcp_client *client) return -ENOMEM; err = client_packet_init(client, DHCP_DISCOVER, &discover->dhcp, - &opt, &optlen); + secs, &opt, &optlen); if (err < 0) return err; @@ -256,7 +260,7 @@ int sd_dhcp_client_start(sd_dhcp_client *client) client->xid = random_u(); - return client_send_discover(client); + return client_send_discover(client, 0); } sd_dhcp_client *sd_dhcp_client_new(void) -- 2.30.2