From 75c172596aa9e7a9f32062579f7f98783341c924 Mon Sep 17 00:00:00 2001
From: Martin Sehnoutka <msehnout@redhat.com>
Date: Wed, 7 Sep 2016 10:17:17 +0200
Subject: [PATCH 08/59] Write denied logins into the log.

This patch adds a new option 'userlist_log'. If enabled,
every login denial based on the user list will be logged.
---
 logging.c     |  7 +++++++
 logging.h     | 11 +++++++++++
 parseconf.c   |  1 +
 prelogin.c    | 14 ++++++++++++++
 tunables.c    |  2 ++
 tunables.h    |  1 +
 vsftpd.conf.5 |  8 ++++++++
 7 files changed, 44 insertions(+)

diff --git a/logging.c b/logging.c
index ad531d6..99671b4 100644
--- a/logging.c
+++ b/logging.c
@@ -103,6 +103,13 @@ vsf_log_line(struct vsf_session* p_sess, enum EVSFLogEntryType what,
   vsf_log_common(p_sess, 1, what, p_str);
 }
 
+void
+vsf_log_failed_line(struct vsf_session* p_sess, enum EVSFLogEntryType what,
+             struct mystr* p_str)
+{
+  vsf_log_common(p_sess, 0, what, p_str);
+}
+
 int
 vsf_log_entry_pending(struct vsf_session* p_sess)
 {
diff --git a/logging.h b/logging.h
index 48f88ec..1ff57d1 100644
--- a/logging.h
+++ b/logging.h
@@ -80,5 +80,16 @@ void vsf_log_do_log(struct vsf_session* p_sess, int succeeded);
 void vsf_log_line(struct vsf_session* p_sess, enum EVSFLogEntryType what,
                   struct mystr* p_str);
 
+/* vsf_log_failed_line()
+ * PURPOSE
+ * Same as vsf_log_line(), except that it logs the line as failed operation.
+ * PARAMETERS
+ * p_sess       - the current session object
+ * what         - the type of operation to log
+ * p_str        - the string to log
+ */
+void vsf_log_failed_line(struct vsf_session* p_sess, enum EVSFLogEntryType what,
+                  struct mystr* p_str);
+
 #endif /* VSF_LOGGING_H */
 
diff --git a/parseconf.c b/parseconf.c
index ea2242b..385afd2 100644
--- a/parseconf.c
+++ b/parseconf.c
@@ -91,6 +91,7 @@ parseconf_bool_array[] =
   { "mdtm_write", &tunable_mdtm_write },
   { "lock_upload_files", &tunable_lock_upload_files },
   { "pasv_addr_resolve", &tunable_pasv_addr_resolve },
+  { "userlist_log", &tunable_userlist_log },
   { "debug_ssl", &tunable_debug_ssl },
   { "require_cert", &tunable_require_cert },
   { "validate_cert", &tunable_validate_cert },
diff --git a/prelogin.c b/prelogin.c
index df4aade..1588bc1 100644
--- a/prelogin.c
+++ b/prelogin.c
@@ -246,6 +246,20 @@ handle_user_command(struct vsf_session* p_sess)
       check_login_delay();
       vsf_cmdio_write(p_sess, FTP_LOGINERR, "Permission denied.");
       check_login_fails(p_sess);
+      if (tunable_userlist_log)
+      {
+        struct mystr str_log_line = INIT_MYSTR;
+        if (tunable_userlist_deny)
+        {
+          str_alloc_text(&str_log_line, "User is in the deny user list.");
+        }
+        else
+        {
+          str_alloc_text(&str_log_line, "User is not in the allow user list.");
+        }
+        vsf_log_failed_line(p_sess, kVSFLogEntryLogin, &str_log_line);
+        str_free(&str_log_line);
+      }
       str_empty(&p_sess->user_str);
       return;
     }
diff --git a/tunables.c b/tunables.c
index 0ac4c34..b30fca1 100644
--- a/tunables.c
+++ b/tunables.c
@@ -72,6 +72,7 @@ int tunable_force_anon_data_ssl;
 int tunable_mdtm_write;
 int tunable_lock_upload_files;
 int tunable_pasv_addr_resolve;
+int tunable_userlist_log;
 int tunable_debug_ssl;
 int tunable_require_cert;
 int tunable_validate_cert;
@@ -212,6 +213,7 @@ tunables_load_defaults()
   tunable_mdtm_write = 1;
   tunable_lock_upload_files = 1;
   tunable_pasv_addr_resolve = 0;
+  tunable_userlist_log = 0;
   tunable_debug_ssl = 0;
   tunable_require_cert = 0;
   tunable_validate_cert = 0;
diff --git a/tunables.h b/tunables.h
index 05d2456..e44d64c 100644
--- a/tunables.h
+++ b/tunables.h
@@ -73,6 +73,7 @@ extern int tunable_force_anon_data_ssl;       /* Require anon data uses SSL */
 extern int tunable_mdtm_write;                /* Allow MDTM to set timestamps */
 extern int tunable_lock_upload_files;         /* Lock uploading files */
 extern int tunable_pasv_addr_resolve;         /* DNS resolve pasv_addr */
+extern int tunable_userlist_log;              /* Log every failed login attempt */
 extern int tunable_debug_ssl;                 /* Verbose SSL logging */
 extern int tunable_require_cert;              /* SSL client cert required */
 extern int tunable_validate_cert;             /* SSL certs must be valid */
diff --git a/vsftpd.conf.5 b/vsftpd.conf.5
index 5e46a2f..9d767b1 100644
--- a/vsftpd.conf.5
+++ b/vsftpd.conf.5
@@ -586,6 +586,14 @@ Default: NO
 If set to yes, all SSL client certificates received must validate OK.
 Self-signed certs do not constitute OK validation. (New in v2.0.6).
 
+Default: NO
+.TP
+.B userlist_log
+This option is examined if
+.BR userlist_enable
+is activated. If enabled, every login denial based on the user list will be
+logged.
+
 Default: NO
 .TP
 .B virtual_use_local_privs
-- 
2.14.4