diff -uNr libsrtp-2.1.0.ORIG/configure.in libsrtp-2.1.0/configure.in
--- libsrtp-2.1.0.ORIG/configure.in	2017-09-18 23:53:18.241631991 +0100
+++ libsrtp-2.1.0/configure.in	2017-09-18 23:55:30.077635461 +0100
@@ -272,10 +272,13 @@
 AC_SUBST([HMAC_OBJS])
 
 dnl Checking for PCAP
+AC_ARG_ENABLE([pcap], AS_HELP_STRING([--disable-pcap], [Build without `pcap' library (-lpcap)]))
+AS_IF([test "x$enable_pcap" != "xno"], [
 AC_CHECK_LIB([pcap], [pcap_create],
   [LIBS="-lpcap $LIBS"
    AC_DEFINE([HAVE_PCAP], [1], [Define to 1 if you have the `pcap' library (-lpcap)])
    AC_SUBST([HAVE_PCAP], [1])])
+])
 
 AC_MSG_CHECKING([whether to redirect logging to stdout])
 AC_ARG_ENABLE([log-stdout],