From 5d21854eb65837214da233de3f2834b8b291b1da Mon Sep 17 00:00:00 2001
From: magnum <john.magnum@hushmail.com>
Date: Mon, 23 Sep 2013 01:45:24 +0200
Subject: [PATCH] Experimental: Add Hashcat-style +N and -N commands
 (increment/decrement ASCII).

---
 run/john.conf | 11 +++++++++++
 src/rules.c   | 18 ++++++++++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/run/john.conf b/run/john.conf
index ae83982..0829769 100644
--- a/run/john.conf
+++ b/run/john.conf
@@ -482,6 +482,16 @@ l Az"[1-90][0-9][0-9]" <+
 :
 ->F>F'F
 
+# Jumbo-specific
+# '+N' rule increments ('ASCII increment') character in position N.
+# '-N' rule decrements it.
+[List.Rules:IncDec]
+# Increment last character:
++m
+# Decrement last character,
+# M is used as a no-op to protect from being parsed as a reject rule:
+M-m
+
 # For Single Mode against fast hashes
 [List.Rules:Single-Extra]
 .include [List.Rules:Single]
@@ -493,6 +503,7 @@ l Az"[1-90][0-9][0-9]" <+
 .include [List.Rules:Single]
 .include [List.Rules:Extra]
 .include [List.Rules:NT]
+.include [List.Rules:IncDec]
 
 # Incremental modes
 
diff --git a/src/rules.c b/src/rules.c
index 5b72759..a263d79 100644
--- a/src/rules.c
+++ b/src/rules.c
@@ -1261,6 +1261,14 @@ char *rules_apply(char *word, char *rule, int split, char *last)
 			}
 			break;
 
+		case '-':
+			{
+				int pos;
+				POSITION(pos)
+				in[pos]--;
+			}
+			break;
+
 		case 'D':
 			{
 				int pos;
@@ -1460,8 +1468,14 @@ char *rules_apply(char *word, char *rule, int split, char *last)
 				}
 				break;
 
-			default:
-				goto out_ERROR_UNALLOWED;
+			default: /* ASCII increment */
+				{
+					int pos;
+					POSITION(pos)
+					in[pos]++;
+				}
+				break;
+
 			}
 			length = strlen(in);
 			which = 0;
-- 
1.8.2.3