diff -up vim82/src/config.h.in.fips-warning vim82/src/config.h.in

--- vim82/src/config.h.in.fips-warning	2021-06-23 11:46:55.000000000 +0200

+++ vim82/src/config.h.in	2021-06-23 11:55:03.165480970 +0200

@@ -501,3 +501,12 @@

 /* Define if _SC_SIGSTKSZ is available via sysconf() */

 #undef HAVE_SYSCONF_SIGSTKSZ

+

+/* Do we need FIPS warning? */

+#undef HAVE_FIPS_WARNING

+

+/* Link to system-fips file */

+#undef SYSTEM_FIPS_FILE_LINK

+

+/* Link to fips_enabled file */

+#undef FIPS_ENABLED_FILE_LINK

diff -up vim82/src/configure.ac.fips-warning vim82/src/configure.ac

--- vim82/src/configure.ac.fips-warning	2021-06-23 11:55:03.163480985 +0200

+++ vim82/src/configure.ac	2021-06-23 11:55:03.166480962 +0200

@@ -541,6 +541,38 @@ else

   AC_MSG_RESULT(yes)

 fi

+dnl Checking if we want FIPS warning

+

+AC_MSG_CHECKING(--enable-fips-warning)

+AC_ARG_ENABLE([fips-warning],

+              AS_HELP_STRING([--enable-fips-warning], [Enable FIPS warning]),

+              ,[enable_fips_warning="no"])

+

+if test "$enable_fips_warning" = "yes"; then

+  AC_MSG_RESULT(yes)

+  AC_DEFINE([HAVE_FIPS_WARNING])

+

+  dnl Setting path for system-fips file

+

+  AC_MSG_CHECKING(--with-system-fips-file argument)

+  AC_ARG_WITH([system-fips-file], [  --with-system-fips-file=PATH       Link to system-fips file (default: /etc/system-fips)],

+	with_system_fips_file=$withval,

+       with_system_fips_file="/etc/system-fips")

+  AC_MSG_RESULT([$with_system_fips_file])

+  AC_DEFINE_UNQUOTED([SYSTEM_FIPS_FILE_LINK], ["$with_system_fips_file"])

+

+  dnl Setting link to fips_enabled file

+

+  AC_MSG_CHECKING(--with-fips-enabled-file argument)

+  AC_ARG_WITH([fips-enabled-file], [  --with-fips-enabled-file=PATH       Link to fibs_enabled file (default: /proc/sys/crypto/fips_enabled)],

+	with_fips_enabled_file=$withval,

+       with_fips_enabled_file="/proc/sys/crypto/fips_enabled")

+  AC_MSG_RESULT([$with_fips_enabled_file])

+  AC_DEFINE_UNQUOTED([FIPS_ENABLED_FILE_LINK], ["$with_fips_enabled_file"])

+else

+  AC_MSG_RESULT(no)

+fi

+

 dnl Check for Lua feature.

 AC_MSG_CHECKING(--enable-luainterp argument)

 AC_ARG_ENABLE(luainterp,

diff -up vim82/src/crypt.c.fips-warning vim82/src/crypt.c

--- vim82/src/crypt.c.fips-warning	2021-06-23 11:55:03.166480962 +0200

+++ vim82/src/crypt.c	2021-06-23 12:36:22.295488425 +0200

@@ -603,6 +603,21 @@ crypt_check_method(int method)

 	msg_scroll = TRUE;

 	msg(_("Warning: Using a weak encryption method; see :help 'cm'"));

     }

+#ifdef HAVE_FIPS_WARNING

+    FILE *fips_enable_fd = fopen(FIPS_ENABLED_FILE_LINK, "r");

+    if (fips_enable_fd == NULL)

+      return;

+

+    int enabled = fgetc(fips_enable_fd);

+

+    if ( access(SYSTEM_FIPS_FILE_LINK, F_OK) != -1 && enabled == '1')

+    {

+	msg_scroll = TRUE;

+	msg(_("Warning: This cryptography is not FIPS 140-2 compliant."));

+    }

+

+    fclose(fips_enable_fd);

+#endif

 }

 #ifdef FEAT_SODIUM