2 files changed, 17 insertions, 0 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index e9a841204..ca82d37e6 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -407,11 +407,19 @@ static ALWAYS_INLINE uint32_t random_xid(void)
 /* Initialize the packet with the proper defaults */
 static void init_packet(struct dhcp_packet *packet, char type)
 {
+        uint16_t secs;
+
         /* Fill in: op, htype, hlen, cookie fields; message type option: */
         udhcp_init_header(packet, type);
 
         packet->xid = random_xid();
 
+        client_config.last_secs = monotonic_sec();
+        if (client_config.first_secs == 0)
+                client_config.first_secs = client_config.last_secs;
+        secs = client_config.last_secs - client_config.first_secs;
+        packet->secs = htons(secs);
+
         memcpy(packet->chaddr, client_config.client_mac, 6);
         if (client_config.clientid)
                 udhcp_add_binary_option(packet, client_config.clientid);
@@ -848,6 +856,7 @@ static void change_listen_mode(int new_mode)
         /* else LISTEN_NONE: sockfd stays closed */
 }
 
+/* Called only on SIGUSR1 */
 static void perform_renew(void)
 {
         bb_info_msg("Performing a DHCP renew");
@@ -1260,6 +1269,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                         case BOUND:
                                 /* 1/2 lease passed, enter renewing state */
                                 state = RENEWING;
+                                client_config.first_secs = 0; /* make secs field count from 0 */
                                 change_listen_mode(LISTEN_KERNEL);
                                 log1("Entering renew state");
                                 /* fall right through */
@@ -1299,6 +1309,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 bb_info_msg("Lease lost, entering init state");
                                 udhcp_run_script(NULL, "deconfig");
                                 state = INIT_SELECTING;
+                                client_config.first_secs = 0; /* make secs field count from 0 */
                                 /*timeout = 0; - already is */
                                 packet_num = 0;
                                 continue;
@@ -1315,6 +1326,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                 /* note: udhcp_sp_read checks FD_ISSET before reading */
                 switch (udhcp_sp_read(&rfds)) {
                 case SIGUSR1:
+                        client_config.first_secs = 0; /* make secs field count from 0 */
                         perform_renew();
                         if (state == RENEW_REQUESTED)
                                 goto case_RENEW_REQUESTED;
@@ -1446,6 +1458,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                                         udhcp_run_script(NULL, "deconfig");
                                                 change_listen_mode(LISTEN_RAW);
                                                 state = INIT_SELECTING;
+                                                client_config.first_secs = 0; /* make secs field count from 0 */
                                                 requested_ip = 0;
                                                 timeout = tryagain_timeout;
                                                 packet_num = 0;
@@ -1493,6 +1506,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 change_listen_mode(LISTEN_RAW);
                                 sleep(3); /* avoid excessive network traffic */
                                 state = INIT_SELECTING;
+                                client_config.first_secs = 0; /* make secs field count from 0 */
                                 requested_ip = 0;
                                 timeout = 0;
                                 packet_num = 0;
diff --git a/networking/udhcp/dhcpc.h b/networking/udhcp/dhcpc.h
index 9ef053a1b..2b3599120 100644
--- a/networking/udhcp/dhcpc.h
+++ b/networking/udhcp/dhcpc.h
@@ -21,6 +21,9 @@ struct client_config_t {
         uint8_t *vendorclass;           /* Optional vendor class-id to use */
         uint8_t *hostname;              /* Optional hostname to use */
         uint8_t *fqdn;                  /* Optional fully qualified domain name to use */
+
+        uint16_t first_secs;
+        uint16_t last_secs;
 } FIX_ALIASING;
 
 /* server_config sits in 1st half of bb_common_bufsiz1 */