From 3a0c90898338c04bde314bede9f116f299eaddef Mon Sep 17 00:00:00 2001
From: Bram Moolenaar <Bram@vim.org>
Date: Wed, 12 Nov 2014 15:15:42 +0100
Subject: [PATCH] updated for version 7.4.509 Problem:    Users are not aware
 their encryption is weak. Solution:   Give a warning when prompting for the
 key.

---
 src/crypt.c         | 20 ++++++++++++++++++++
 src/ex_docmd.c      |  1 +
 src/fileio.c        |  1 +
 src/main.c          |  1 +
 src/proto/crypt.pro |  2 ++
 src/version.c       |  2 ++
 6 files changed, 27 insertions(+)

diff --git a/src/crypt.c b/src/crypt.c
index c54e15c4a..f25a2c4a9 100644
--- a/src/crypt.c
+++ b/src/crypt.c
@@ -503,6 +503,26 @@ crypt_free_key(key)
     }
 }
 
+/*
+ * Check the crypt method and give a warning if it's outdated.
+ */
+    void
+crypt_check_method(method)
+    int method;
+{
+    if (method < CRYPT_M_BF2)
+    {
+	msg_scroll = TRUE;
+	MSG(_("Warning: Using a weak encryption method; see :help 'cm'"));
+    }
+}
+
+    void
+crypt_check_current_method()
+{
+    crypt_check_method(crypt_get_method_nr(curbuf));
+}
+
 /*
  * Ask the user for a crypt key.
  * When "store" is TRUE, the new key is stored in the 'key' option, and the
diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 35e44f0f3..e90a36ecc 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -11524,6 +11524,7 @@ ex_match(eap)
 ex_X(eap)
     exarg_T	*eap UNUSED;
 {
+    crypt_check_current_method();
     (void)crypt_get_key(TRUE, TRUE);
 }
 #endif
diff --git a/src/fileio.c b/src/fileio.c
index 0843d0429..a978ec241 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2958,6 +2958,7 @@ check_for_cryptkey(cryptkey, ptr, sizep, filesizep, newfile, fname, did_ask)
 		 * Happens when retrying to detect encoding. */
 		smsg((char_u *)_(need_key_msg), fname);
 		msg_scroll = TRUE;
+		crypt_check_method(method);
 		cryptkey = crypt_get_key(newfile, FALSE);
 		*did_ask = TRUE;
 
diff --git a/src/main.c b/src/main.c
index fe7549582..181438519 100644
--- a/src/main.c
+++ b/src/main.c
@@ -854,6 +854,7 @@ vim_main2(int argc UNUSED, char **argv UNUSED)
 #ifdef FEAT_CRYPT
     if (params.ask_for_key)
     {
+	crypt_check_current_method();
 	(void)crypt_get_key(TRUE, TRUE);
 	TIME_MSG("getting crypt key");
     }
diff --git a/src/proto/crypt.pro b/src/proto/crypt.pro
index d61df718b..7b29026a1 100644
--- a/src/proto/crypt.pro
+++ b/src/proto/crypt.pro
@@ -19,6 +19,8 @@ void crypt_decode __ARGS((cryptstate_T *state, char_u *from, size_t len, char_u
 void crypt_encode_inplace __ARGS((cryptstate_T *state, char_u *buf, size_t len));
 void crypt_decode_inplace __ARGS((cryptstate_T *state, char_u *buf, size_t len));
 void crypt_free_key __ARGS((char_u *key));
+void crypt_check_method __ARGS((int method));
+void crypt_check_current_method __ARGS((void));
 char_u *crypt_get_key __ARGS((int store, int twice));
 void crypt_append_msg __ARGS((buf_T *buf));
 /* vim: set ft=c : */
diff --git a/src/version.c b/src/version.c
index 76ab14690..06c4016be 100644
--- a/src/version.c
+++ b/src/version.c
@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    509,
 /**/
     508,
 /**/
-- 
2.40.0