squidclamav: Never use IPv6.

Squidclamav uses curl to resolve all kind of addresses which the system allow.
If the remote address is an IPv6 address, squidclamav hangs forever.

Nico Prenzel has found a solution to force the usage of IPv4 to prevent from this
issue.

Fixes #10376.

lfs/squidclamav

@@ -32,7 +32,7 @@ DL_FROM    = $(URL_IPFIRE)
 DIR_APP    = $(DIR_SRC)/$(THISAPP)
 TARGET     = $(DIR_INFO)/$(THISAPP)
 PROG       = squidclamav
-PAK_VER    = 16
+PAK_VER    = 17
 
 DEPS       = "clamav"
 
@@ -77,6 +77,7 @@ $(subst %,%_MD5,$(objects)) :
 $(TARGET) : $(patsubst %,$(DIR_DL)/%,$(objects))
 	@$(PREBUILD)
 	@rm -rf $(DIR_APP) && cd $(DIR_SRC) && tar zxf $(DIR_DL)/$(DL_FILE)
+	cd $(DIR_APP) && patch -Np1 < $(DIR_SRC)/src/patches/squidclamav-5.11-dont_use_ipv6.patch
 	cd $(DIR_APP) && ./configure --prefix=/usr
 	cd $(DIR_APP) && make install
 	install -v -m 755  $(DIR_CONF)/squidclamav/squidclamav.conf /etc/squidclamav.conf

src/patches/squidclamav-5.11-dont_use_ipv6.patch

@@ -0,0 +1,13 @@
+diff -Nur a/src/squidclamav.c b/src/squidclamav.c
+--- a/src/squidclamav.c	2012-10-29 09:46:06.000000000 +0100
++++ b/src/squidclamav.c	2013-07-06 19:10:56.375292374 +0200
+@@ -413,6 +413,9 @@
+ 	  /* Suppress error: SSL certificate problem, verify that the CA cert is OK */
+ 	  curl_easy_setopt (eh, CURLOPT_SSL_VERIFYHOST, 0);
+ 	  curl_easy_setopt (eh, CURLOPT_SSL_VERIFYPEER, 0);
++
++	  /* Prevent squidclamav from using IPv6 - fix by Nico Prenzel */
++	  curl_easy_setopt (eh, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
+ 	}
+    }
+   /* create a squidguard child process and setup pipes */