Allow reverting the SHA1 ban as a signature algorithm

This allows distributors to decide not to ban SHA1. This
option may be removed in the future.

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

diff --git a/configure.ac b/configure.ac
index 9b6d6f65e5224dbafc80d83d1107e1d41cf6ebe9..b98c47033c4026e803b7046ee13fe34be270b358 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1040,6 +1040,7 @@ if features are disabled)
 
   SSL3.0 support:       $ac_enable_ssl3
   SSL2.0 client hello:  $ac_enable_ssl2
+  Allow SHA1 sign:      $ac_allow_sha1
   DTLS-SRTP support:    $ac_enable_srtp
   ALPN support:         $ac_enable_alpn
   OCSP support:         $ac_enable_ocsp

diff --git a/lib/algorithms/mac.c b/lib/algorithms/mac.c
index 90db39d3d143cc7d810d52d1cfbad67668137c48..f9b353740335640e5f1743c79d3066d28b5617a4 100644 (file)
--- a/lib/algorithms/mac.c
+++ b/lib/algorithms/mac.c
@@ -31,8 +31,14 @@
 #define MAC_OID_SHA384 "1.2.840.113549.2.10"
 #define MAC_OID_SHA512 "1.2.840.113549.2.11"
 
+#ifdef ALLOW_SHA1
+# define SHA1_SECURE_VAL 1
+#else
+# define SHA1_SECURE_VAL 0
+#endif
+
 static const mac_entry_st hash_algorithms[] = {
-       {"SHA1", HASH_OID_SHA1, MAC_OID_SHA1, GNUTLS_MAC_SHA1, 20, 20, 0, 0, 0, 64},
+       {"SHA1", HASH_OID_SHA1, MAC_OID_SHA1, GNUTLS_MAC_SHA1, 20, 20, 0, 0, SHA1_SECURE_VAL, 64},
        {"MD5", HASH_OID_MD5, NULL, GNUTLS_MAC_MD5, 16, 16, 0, 0, 0, 64},
        {"MD5+SHA1", NULL, NULL, GNUTLS_MAC_MD5_SHA1, 36, 36, 0, 0, 0, 64},
        {"SHA256", HASH_OID_SHA256, MAC_OID_SHA256, GNUTLS_MAC_SHA256, 32, 32, 0, 0, 1,

diff --git a/m4/hooks.m4 b/m4/hooks.m4
index e8d80a549d9ff708fb8ba50fcfc70c4647f1dc57..1c4f5b50ce644e8e0d1b07db34e99a9ce10e2c9d 100644 (file)
--- a/m4/hooks.m4
+++ b/m4/hooks.m4
@@ -142,6 +142,20 @@ LIBTASN1_MINIMUM=4.9
     AC_MSG_WARN([C99 macros not supported. This may affect compiling.])
   ])
 
+  ac_allow_sha1=no
+  AC_MSG_CHECKING([whether to allow SHA1 as an acceptable hash for digital signatures])
+  AC_ARG_ENABLE(sha1-support,
+    AS_HELP_STRING([--enable-sha1-support],
+                   [allow SHA1 as an acceptable hash for digital signatures]),
+    ac_allow_sha1=$enableval)
+  if test x$ac_allow_sha1 != xno; then
+   AC_MSG_RESULT(no)
+   AC_DEFINE([ALLOW_SHA1], 1, [allow SHA1 as an acceptable hash for digital signatures])
+  else
+   AC_MSG_RESULT(yes)
+  fi
+  AM_CONDITIONAL(ALLOW_SHA1, test "$ac_allow_sha1" != "no")
+
   ac_enable_ssl3=yes
   AC_MSG_CHECKING([whether to disable the SSL 3.0 protocol])
   AC_ARG_ENABLE(ssl3-support,