From 346e13a25dc6f76d3bc9d8decd40dc4782b02d2a Mon Sep 17 00:00:00 2001

From: Patrik Flykt <patrik.flykt@linux.intel.com>

Date: Mon, 1 Sep 2014 13:21:33 +0300

Subject: [PATCH] sd-dhcp6-client: Implement Elapsed Time option

Implement Elapsed Time option as it is defined as MUST in RFC 3315,

section 22.9. The elapsed time value is a 1/100th of a second with

a max value of 0xffff, i.e. 655.35 seconds.

As the main loop might not be running yet when sd_dhcp6_client_start() is

called, fetch the monotonic time directly and not from the event loop

while in state DHCP6_STATE_STOPPED.

---

 src/libsystemd-network/sd-dhcp6-client.c | 40 ++++++++++++++++++++++++--------

 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/src/libsystemd-network/sd-dhcp6-client.c b/src/libsystemd-network/sd-dhcp6-client.c

index 6860c66858..c190b560ea 100644

--- a/src/libsystemd-network/sd-dhcp6-client.c

+++ b/src/libsystemd-network/sd-dhcp6-client.c

@@ -49,6 +49,7 @@ struct sd_dhcp6_client {

         struct ether_addr mac_addr;

         DHCP6IA ia_na;

         be32_t transaction_id;

+        usec_t transaction_start;

         struct sd_dhcp6_lease *lease;

         int fd;

         be16_t *req_opts;

@@ -203,6 +204,7 @@ static int client_reset(sd_dhcp6_client *client) {

         client->fd = safe_close(client->fd);

         client->transaction_id = 0;

+        client->transaction_start = 0;

         client->ia_na.timeout_t1 =

                 sd_event_source_unref(client->ia_na.timeout_t1);

@@ -230,13 +232,15 @@ static void client_stop(sd_dhcp6_client *client, int error) {

         client_reset(client);

 }

-static int client_send_message(sd_dhcp6_client *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;

         len = sizeof(DHCP6Message) + optlen;

@@ -308,6 +312,17 @@ static int client_send_message(sd_dhcp6_client *client) {

         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, 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)

@@ -455,15 +470,14 @@ static int client_timeout_resend(sd_event_source *s, uint64_t usec,

                 return 0;

         }

-        r = client_send_message(client);

-        if (r >= 0)

-                client->retransmit_count++;

-

-

         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);

@@ -882,6 +896,15 @@ static int client_start(sd_dhcp6_client *client, enum DHCP6State state)

         client->retransmit_time = 0;

         client->retransmit_count = 0;

+        if (client->state == DHCP6_STATE_STOPPED) {

+                time_now = now(clock_boottime_or_monotonic());

+        } else {

+                r = sd_event_now(client->event, clock_boottime_or_monotonic(),

+                                 &time_now);

+                if (r < 0)

+                        return r;

+        }

+

         switch (state) {

         case DHCP6_STATE_STOPPED:

         case DHCP6_STATE_SOLICITATION:

@@ -926,10 +949,6 @@ static int client_start(sd_dhcp6_client *client, enum DHCP6State state)

         case DHCP6_STATE_BOUND:

-                r = sd_event_now(client->event, clock_boottime_or_monotonic(), &time_now);

-                if (r < 0)

-                        return r;

-

                 if (client->lease->ia.lifetime_t1 == 0xffffffff ||

                     client->lease->ia.lifetime_t2 == 0xffffffff) {

@@ -996,6 +1015,7 @@ static int client_start(sd_dhcp6_client *client, enum DHCP6State state)

         }

         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,