From 71db577ed53adb2a5c006b013e3ca0e005a1fb08 Mon Sep 17 00:00:00 2001
From: "Nicholas J. Kain" <nicholas@kain.us>
Date: Sat, 22 Mar 2014 02:08:23 -0400
Subject: [PATCH] Replace the remaining calls to rand() with nk_random_u32().

---
 ndhc/arp.c   | 7 ++++---
 ndhc/state.c | 9 +++++----
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/ndhc/arp.c b/ndhc/arp.c
index b6689ac..ec50cda 100644
--- a/ndhc/arp.c
+++ b/ndhc/arp.c
@@ -561,10 +561,11 @@ static int arp_is_query_reply(struct arpMsg *am)
     return 1;
 }
 
-static int arp_gen_probe_wait(void)
+static int arp_gen_probe_wait(struct client_state_t *cs)
 {
     // This is not a uniform distribution but it doesn't matter here.
-    return arp_probe_min + rand() % (arp_probe_max - arp_probe_min);
+    return arp_probe_min + (nk_random_u32(&cs->rnd32_state) & 0x7fffffffu)
+        % (arp_probe_max - arp_probe_min);
 }
 
 static void arp_defense_timeout(struct client_state_t *cs, long long nowts)
@@ -642,7 +643,7 @@ static void arp_collision_timeout(struct client_state_t *cs, long long nowts)
     }
     if (arp_ip_anon_ping(cs, arp_dhcp_packet.yiaddr) == -1)
         log_warning("arp: Failed to send ARP ping in retransmission.");
-    probe_wait_time = arp_gen_probe_wait();
+    probe_wait_time = arp_gen_probe_wait(cs);
     arp_wake_ts[AS_COLLISION_CHECK] =
         arp_send_stats[ASEND_COLLISION_CHECK].ts + probe_wait_time;
 }
diff --git a/ndhc/state.c b/ndhc/state.c
index 71408b4..4978243 100644
--- a/ndhc/state.c
+++ b/ndhc/state.c
@@ -77,13 +77,14 @@ static const dhcp_state_t dhcp_states[] = {
 static unsigned int num_dhcp_requests;
 static long long dhcp_wake_ts = -1;
 
-static int delay_timeout(size_t numpackets)
+static int delay_timeout(struct client_state_t *cs, size_t numpackets)
 {
     int to = 64;
     char tot[] = { 4, 8, 16, 32, 64 };
     if (numpackets < sizeof tot)
         to = tot[numpackets];
-    return to * 1000 + rand() % 1000;
+    // Distribution is a bit biased but it doesn't really matter.
+    return to * 1000 + (nk_random_u32(&cs->rnd32_state) & 0x7fffffffu) % 1000;
 }
 
 static void reinit_shared_deconfig(struct client_state_t *cs)
@@ -123,7 +124,7 @@ static void requesting_timeout(struct client_state_t *cs, long long nowts)
 {
     if (num_dhcp_requests < 5) {
         send_selecting(cs);
-        dhcp_wake_ts = nowts + delay_timeout(num_dhcp_requests);
+        dhcp_wake_ts = nowts + delay_timeout(cs, num_dhcp_requests);
         num_dhcp_requests++;
     } else
         reinit_selecting(cs, 0);
@@ -309,7 +310,7 @@ static void selecting_timeout(struct client_state_t *cs, long long nowts)
     if (num_dhcp_requests == 0)
         cs->xid = nk_random_u32(&cs->rnd32_state);
     send_discover(cs);
-    dhcp_wake_ts = nowts + delay_timeout(num_dhcp_requests);
+    dhcp_wake_ts = nowts + delay_timeout(cs, num_dhcp_requests);
     num_dhcp_requests++;
 }