Add maxsequence check for too long monotonic character sequence.

5 files changed, 52 insertions, 0 deletions

diff --git a/src/check.c b/src/check.c
index 5303b51..f72c351 100644
--- a/src/check.c
+++ b/src/check.c
@@ -329,6 +329,45 @@ consecutive(pwquality_settings_t *pwq, const char *new, void **auxerror)
         return 0;
 }
 
+static int sequence(pwquality_settings_t *pwq, const char *new, void **auxerror)
+{
+        char c;
+        int i;
+        int sequp = 1;
+        int seqdown = 1;
+
+        if (pwq->max_sequence == 0)
+                return 0;
+
+        if (new[0] == '\0')
+                return 0;
+
+        for (i = 1; new[i]; i++) {
+                c = new[i-1];
+                if (new[i] == c+1) {
+                        ++sequp;
+                        if (sequp > pwq->max_sequence) {
+                                if (auxerror)
+                                        *auxerror = (void *)(long)pwq->max_sequence;
+                                return 1;
+                        }
+                        seqdown = 1;
+                } else if (new[i] == c-1) {
+                        ++seqdown;
+                        if (seqdown > pwq->max_sequence) {
+                                if (auxerror)
+                                        *auxerror = (void *)(long)pwq->max_sequence;
+                                return 1;
+                        }
+                        sequp = 1;
+                } else {
+                        sequp = 1;
+                        seqdown = 1;
+                }
+        }
+        return 0;
+}
+
 static int
 usercheck(pwquality_settings_t *pwq, const char *new,
           char *user)
@@ -511,6 +550,9 @@ password_check(pwquality_settings_t *pwq,
         if (!rv && consecutive(pwq, new, auxerror))
                 rv = PWQ_ERROR_MAX_CONSECUTIVE;
 
+        if (!rv && sequence(pwq, new, auxerror))
+                rv = PWQ_ERROR_MAX_SEQUENCE;
+
         if (!rv && usermono && usercheck(pwq, newmono, usermono))
                 rv = PWQ_ERROR_USER_CHECK;
 
diff --git a/src/error.c b/src/error.c
index 25e834b..4928097 100644
--- a/src/error.c
+++ b/src/error.c
@@ -97,6 +97,12 @@ pwquality_strerror(char *buf, size_t len, int rv, void *auxerror)
                         return buf;
                 }
                 return _("The password contains too many characters of the same class consecutively");
+        case PWQ_ERROR_MAX_SEQUENCE:
+                if (auxerror) {
+                        snprintf(buf, len, _("The password contains monotonic sequence longer than %ld characters"), (long)auxerror);
+                        return buf;
+                }
+                return _("The password contains too long of a monotonic character sequence");
         case PWQ_ERROR_EMPTY_PASSWORD:
                 return _("No password supplied");
         case PWQ_ERROR_RNG:
diff --git a/src/pwqprivate.h b/src/pwqprivate.h
index 092a6f3..0e3df81 100644
--- a/src/pwqprivate.h
+++ b/src/pwqprivate.h
@@ -22,6 +22,7 @@ struct pwquality_settings {
         int min_class;
         int max_repeat;
         int max_class_repeat;
+        int max_sequence;
         int gecos_check;
         char *bad_words;
         char *dict_path;
diff --git a/src/pwquality.h b/src/pwquality.h
index e22b084..1657ca1 100644
--- a/src/pwquality.h
+++ b/src/pwquality.h
@@ -22,6 +22,7 @@
 #define PWQ_SETTING_MAX_CLASS_REPEAT 11
 #define PWQ_SETTING_GECOS_CHECK     12
 #define PWQ_SETTING_BAD_WORDS       13
+#define PWQ_SETTING_MAX_SEQUENCE    14
 
 #define PWQ_MAX_ENTROPY_BITS       256
 #define PWQ_MIN_ENTROPY_BITS       56
@@ -57,6 +58,7 @@
 #define PWQ_ERROR_GECOS_CHECK                  -26
 #define PWQ_ERROR_MAX_CLASS_REPEAT             -27
 #define PWQ_ERROR_BAD_WORDS                    -28
+#define PWQ_ERROR_MAX_SEQUENCE                 -29
 
 typedef struct pwquality_settings pwquality_settings_t;
 
diff --git a/src/settings.c b/src/settings.c
index f57db85..9ba3e62 100644
--- a/src/settings.c
+++ b/src/settings.c
@@ -57,6 +57,7 @@ static const struct setting_mapping s_map[] = {
  { "minclass", PWQ_SETTING_MIN_CLASS, PWQ_TYPE_INT},
  { "maxrepeat", PWQ_SETTING_MAX_REPEAT, PWQ_TYPE_INT},
  { "maxclassrepeat", PWQ_SETTING_MAX_CLASS_REPEAT, PWQ_TYPE_INT},
+ { "maxsequence", PWQ_SETTING_MAX_SEQUENCE, PWQ_TYPE_INT},
  { "gecoscheck", PWQ_SETTING_GECOS_CHECK, PWQ_TYPE_INT},
  { "badwords", PWQ_SETTING_BAD_WORDS, PWQ_TYPE_STR},
  { "dictpath", PWQ_SETTING_DICT_PATH, PWQ_TYPE_STR}