From e30931d95894869fa0d7e0e544f2373bfec73e4d Mon Sep 17 00:00:00 2001
From: Marco d'Itri <md@linux.it>
Date: Mon, 5 May 2025 23:41:19 +0200
Subject: [PATCH] Use the last ReferralServer field found

Because we want to follow the referral for the most specific record
returned.

Closes GitHub #185.
---
 whois.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/whois.c b/whois.c
index c86e694..72aecec 100644
--- a/whois.c
+++ b/whois.c
@@ -892,9 +892,6 @@ static void find_referral_server_arin(char **referral_server, const char *buf)
 {
     char *p;
 
-    if (*referral_server)
-	return;
-
     /* ARIN referrals:
      * ReferralServer: rwhois://rwhois.fuse.net:4321/
      * ReferralServer: whois://whois.ripe.net
@@ -903,6 +900,16 @@ static void find_referral_server_arin(char **referral_server, const char *buf)
     if (!strneq(buf, "ReferralServer:", 15))
 	return;
 
+    /* When whois.arin.net returns multiple NetRange records, they will
+     * appear from the less specific one to the most specific one.
+     * Since the range we care about is the most specific one then we
+     * need to use the last ReferralServer field found.
+     */
+    if (*referral_server) {
+	free(*referral_server);
+	*referral_server = NULL;
+    }
+
     if ((p = strstr(buf, "rwhois://")))
 	*referral_server = strdup(p + 9);
     else if ((p = strstr(buf, "whois://")))