sslh: disable libpcre probe support

Backport upstream commit 3aefaf3 which allows sslh to be built without
libpcre support. This was brought about by the move to musl which
doesn't support the non-POSIX REG_STARTEND regexec eflag.

Fixes: #1506

Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>

net/sslh/Makefile

@@ -38,6 +38,7 @@ define Build/Compile
 		CFLAGS="$(TARGET_CFLAGS)" \
 		USELIBCONFIG= \
 		USELIBWRAP= \
+		USELIBPCRE= \
 		all
 endef
 

net/sslh/patches/002-no_regex_probes.patch

@@ -0,0 +1,90 @@
+From 3aefaf300478cd6fbc4892d5baaf70521ed323af Mon Sep 17 00:00:00 2001
+From: Yves Rutschle <git1@rutschle.net>
+Date: Thu, 9 Jul 2015 15:31:42 +0200
+Subject: [PATCH] Added Makefile option to build without libpcre
+
+---
+--- a/Makefile
++++ b/Makefile
+@@ -2,6 +2,7 @@
+ 
+ VERSION=$(shell ./genver.sh -r)
+ USELIBCONFIG=1	# Use libconfig? (necessary to use configuration files)
++USELIBPCRE=1	# Use libpcre? (necessary to use regex probe)
+ USELIBWRAP?=	# Use libwrap?
+ USELIBCAP=	# Use libcap?
+ COV_TEST= 	# Perform test coverage?
+@@ -27,6 +28,10 @@ ifneq ($(strip $(USELIBWRAP)),)
+ 	CPPFLAGS+=-DLIBWRAP
+ endif
+ 
++ifneq ($(strip $(USELIBPCRE)),)
++	CPPFLAGS+=-DLIBPCRE
++endif
++
+ ifneq ($(strip $(USELIBCONFIG)),)
+ 	LIBS:=$(LIBS) -lconfig
+ 	CPPFLAGS+=-DLIBCONFIG
+--- a/probe.c
++++ b/probe.c
+@@ -21,7 +21,9 @@
+ 
+ #define _GNU_SOURCE
+ #include <stdio.h>
++#ifdef LIBPCRE
+ #include <regex.h>
++#endif
+ #include <ctype.h>
+ #include "probe.h"
+ 
+@@ -226,6 +228,7 @@ static int is_tls_protocol(const char *p
+ 
+ static int regex_probe(const char *p, int len, struct proto *proto)
+ {
++#ifdef LIBPCRE
+     regex_t **probe = proto->data;
+     regmatch_t pos = { 0, len };
+ 
+@@ -233,6 +236,11 @@ static int regex_probe(const char *p, in
+         /* try them all */;
+ 
+     return (*probe != NULL);
++#else
++    /* Should never happen as we check when loading config file */
++    fprintf(stderr, "FATAL: regex probe called but not built in\n");
++    exit(5);
++#endif
+ }
+ 
+ /* 
+--- a/sslh-main.c
++++ b/sslh-main.c
+@@ -25,7 +25,9 @@
+ #ifdef LIBCONFIG
+ #include <libconfig.h>
+ #endif
++#ifdef LIBPCRE
+ #include <regex.h>
++#endif
+ 
+ #include "common.h"
+ #include "probe.h"
+@@ -174,6 +176,7 @@ static int config_listen(config_t *confi
+ #ifdef LIBCONFIG
+ static void setup_regex_probe(struct proto *p, config_setting_t* probes)
+ {
++#ifdef LIBPCRE
+     int num_probes, errsize, i, res;
+     char *err;
+     const char * expr;
+@@ -201,6 +204,10 @@ static void setup_regex_probe(struct pro
+             exit(1);
+         }
+     }
++#else
++    fprintf(stderr, "line %d: regex probe specified but not compiled in\n", config_setting_source_line(probes));
++    exit(5);
++#endif
+ }
+ #endif
+