From bd59be8e4e339870a1400f6866a7b73ca11f6460 Mon Sep 17 00:00:00 2001
From: Giulio Benetti <giulio.benetti@micronovasrl.com>
Date: Wed, 12 Sep 2018 20:16:39 +0200
Subject: [PATCH] configure, static linking: Fix SSL checks

During checking of DTLS_method, the stub program is linked only with -ssl
libssl.a lacks some function from -lcrypto:
RAND_*()
ERR_*()
BUF_MEM_*()
etc.
and -lz:
- inflate()
- deflate()

Append -lcrypto and -lz to LIBS variable when checking DTLS_method.

See also https://sourceforge.net/p/net-snmp/patches/1374/.

Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
[bvanassche: Edited subject / rewrote this patch]
[yann.morin.1998@free.fr:
  - use an actual backport of bd59be8e4e339870a1400f6866a7b73ca11f6460
]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
---
 configure                   | 52 ++++++++++++++++++++++++++++++++++---
 configure.d/config_os_libs2 | 14 +++++++---
 2 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/configure b/configure
index 6504a8e58a..1116cecaad 100755
--- a/configure
+++ b/configure
@@ -23228,16 +23228,60 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_crypto_EVP_md5" >&5
 $as_echo "$ac_cv_lib_crypto_EVP_md5" >&6; }
 if test "x$ac_cv_lib_crypto_EVP_md5" = xyes; then :
-  CRYPTO="crypto"
+  CRYPTO="crypto"; LIBCRYPTO="-lcrypto"
+else
+
+		{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for EVP_md5 in -lcrypto" >&5
+$as_echo_n "checking for EVP_md5 in -lcrypto... " >&6; }
+if ${ac_cv_lib_crypto_EVP_md5+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lcrypto -lz $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char EVP_md5 ();
+int
+main ()
+{
+return EVP_md5 ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_crypto_EVP_md5=yes
+else
+  ac_cv_lib_crypto_EVP_md5=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_crypto_EVP_md5" >&5
+$as_echo "$ac_cv_lib_crypto_EVP_md5" >&6; }
+if test "x$ac_cv_lib_crypto_EVP_md5" = xyes; then :
+  CRYPTO="crypto"; LIBCRYPTO="-lcrypto -lz"
+fi
+
+
 fi
 
-        fi
+	else
+	    LIBCRYPTO="-l${CRYPTO}"
+	fi
 
         if test x$CRYPTO != x; then
 
 $as_echo "#define HAVE_LIBCRYPTO 1" >>confdefs.h
 
-            LIBCRYPTO="-l${CRYPTO}"
             netsnmp_save_LIBS="$LIBS"
             LIBS="$LIBCRYPTO"
             for ac_func in AES_cfb128_encrypt                           EVP_sha224        EVP_sha384                                   EVP_MD_CTX_create EVP_MD_CTX_destroy                           EVP_MD_CTX_new    EVP_MD_CTX_free                              DH_set0_pqg DH_get0_pqg DH_get0_key                           ASN1_STRING_get0_data X509_NAME_ENTRY_get_object                           X509_NAME_ENTRY_get_data X509_get_signature_nid
@@ -23291,7 +23335,7 @@ _ACEOF
             LIBS="$netsnmp_save_LIBS"
         fi
         netsnmp_save_LIBS="$LIBS"
-        LIBS="-lssl"
+        LIBS="-lssl $LIBCRYPTO"
         for ac_func in TLS_method TLSv1_method DTLS_method DTLSv1_method                       SSL_library_init SSL_load_error_strings		       ERR_get_error_all
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
diff --git a/configure.d/config_os_libs2 b/configure.d/config_os_libs2
index 4a1ad1551f..75214cfff3 100644
--- a/configure.d/config_os_libs2
+++ b/configure.d/config_os_libs2
@@ -306,13 +306,19 @@ if test "x$tryopenssl" != "xno" -a "x$tryopenssl" != "xinternal"; then
         LIBS="$netsnmp_save_LIBS"
 
         if test x$CRYPTO = x; then
-            AC_CHECK_LIB([crypto], [EVP_md5], [CRYPTO="crypto"])
-        fi
+            AC_CHECK_LIB([crypto], [EVP_md5],
+			 [CRYPTO="crypto"; LIBCRYPTO="-lcrypto"], [
+		AC_CHECK_LIB([crypto], [EVP_md5],
+			     [CRYPTO="crypto"; LIBCRYPTO="-lcrypto -lz"], [],
+			     [-lz])
+	    ])
+	else
+	    LIBCRYPTO="-l${CRYPTO}"
+	fi
 
         if test x$CRYPTO != x; then
             AC_DEFINE(HAVE_LIBCRYPTO, 1,
                 [Define to 1 if you have the OpenSSL library (-lcrypto or -leay32).])
-            LIBCRYPTO="-l${CRYPTO}"
             netsnmp_save_LIBS="$LIBS"
             LIBS="$LIBCRYPTO"
             AC_CHECK_FUNCS([AES_cfb128_encrypt]dnl
@@ -342,7 +348,7 @@ if test "x$tryopenssl" != "xno" -a "x$tryopenssl" != "xinternal"; then
             LIBS="$netsnmp_save_LIBS"
         fi
         netsnmp_save_LIBS="$LIBS"
-        LIBS="-lssl"
+        LIBS="-lssl $LIBCRYPTO"
         AC_CHECK_FUNCS([TLS_method TLSv1_method DTLS_method DTLSv1_method]dnl
                        [SSL_library_init SSL_load_error_strings])
         LIBS="$netsnmp_save_LIBS"
-- 
2.25.1