1.3.6 Release Notes
------------------------
This file contains a description of the major changes to ProFTPD for the
1.3.6 release cycle, from the 1.3.6rc1 release to the 1.3.6 maintenance
releases. More information on these changes can be found in the NEWS and
ChangeLog files.
1.3.6rc1
---------
+ Support the HOST command (see RFC 7151).
+ Changed the default SyslogLevel to be NOTICE, rather than DEBUG.
+ Fixed "stalled" SSL/TLS handshakes for data transfers.
+ ftpwho now supports JSON output format.
+ Fixed handling of SSH keys with overlong Comment headers in mod_sftp_sql.
+ Changed handling of logging of SFTP sessions to ExtendedLogs; see the
notes below on the ExtendedLog directive.
+ Changed Modules
mod_facl
The mod_facl module now supports the MacOSX flavour of POSIX ACLs.
mod_radius
The mod_radius module has added support for the following RADIUS
attributes:
Acct-Terminate-Cause
Event-Timestamp
Idle-Timeout
Message-Authenticator
Reply-Message
Session-Timeout
mod_site_misc
The SITE UTIME command now supports the 3-timestamp variant:
SITE UTIME path atime mtime ctime
where each timestamp is expressed as "YYYYMMDDhhmmss".
mod_sql
The mod_sql module would previously only support 32-bit UID/GID
values, due to its use of the atoi(3) C library function for parsing
result set values into IDs. This has been fixed; mod_sql now
properly supports 64-bit UID/GID values.
mod_tls
By default, mod_tls will no longer support SSLv3 connections. In
order to support SSLv3 connections (for sites that need to), you must
explicitly configure this via the TLSProtocol directive, e.g.:
TLSProtocol SSLv3 TLSv1 ...
In addition, mod_tls will no longer support EXPORT ciphers.
+ New Configuration Directives:
CopyEngine
The mod_copy module is enabled by default; there may be cases where
the module should be disabled, without requiring a rebuild of the
server. Thus mod_copy now supports a CopyEngine directive; see
doc/contrib/mod_copy.html#CopyEngine.
DelayOnEvent
There are sites which wish to use mod_delay for administratively
adding delays to connections as e.g. brute force attack deterrents.
To support these use cases, the mod_delay module has a new DelayOnEvent
directive. Using this directive, sites can configure something like
the following, for forcing a minimum login delay and a failed login
delay:
# Configure successful logins to be delayed by 2 secs
DelayOnEvent PASS 2000ms
# Configure failed logins to be delayed by 5 secs
DelayOnEvent FailedLogin 5s
See doc/modules/mod_delay.html#DelayOnEvent for more information.
ExecEnable
Some sites using mod_exec need to configure a command to be executed,
but wish to "blacklist" certain directories where that command should
not be executed. To handle configurations like this, the mod_exec
module has a new ExecEnable directive; see
doc/contrib/mod_exec.html#ExecEnable for details.
FSCachePolicy
ProFTPD has long maintained a cache of the last stat data for a file.
However, for performance reasons, this cache size needs to be larger,
and to be enhanced to handle expiration, etc. To tune the size
and expiration settings of this filesystem data cache, use the new
FSCachePolicy directive; see doc/modules/mod_core.html#FSCachePolicy
for details.
LangOptions
Currently proftpd tries to cope with various filename/character
encodings used by FTP clients; if it cannot decode the filename, it
will use the sent filename as-is. This behavior can cause problems
for downstream resources that then attempt to deal with these
filenames, and fail. To make proftpd be more strict about the
encoding it accepts, use the new LangOption directive:
LangOptions RequireValidEncoding
See doc/modules/mod_lang.html#LangOptions.
RadiusOptions
The mod_radius module now supports/handles additional RADIUS
attributes. Some of these attribute may need to be ignore for
some sites; others may wish to e.g. enforce stronger security by
requiring the use of the Message-Authenticator attribute. Thus
mod_radius has a new RadiusOptions directive; see
doc/contrib/mod_radius.html#RadiusOptions for details.
ServerAlias
Supporting true name-based virtual hosting means needing to associate
names with the IP-based virtual hosts. The ServerAlias directive is
used to do this association; see doc/modules/mod_core.html#ServerAlias
for details.
SQLPasswordSaltEncoding
In order to handle binary data for salts, the mod_sql_password module
now supports handling of this data as base64- or hex-encoded data
via the new SQLPasswordSaltEncoding directive; see
doc/contrib/mod_sql_passwd.html#SQLPasswordSaltEncoding for details.
TLSECDHCurve
When an FTPS client uses an ECDHE cipher, mod_tls currently will use
the X9.62 prime256v1
curve. Some sites may, however,
wish to use other curves for ECDHE ciphers. These sites may now use
the new TLSECDHCurve directive to configure the curve; see
doc/contrib/mod_tls.html#TLSECDHCurve for details.
TLSNextProtocol
Newer TLS clients use the ALPN (Application Layer Protocol Negotiation)
extension (or its earlier incarnation NPN (Next Protocol Negotiation)
for determining the protocol that will be used over the SSL/TLS
session. The support for these extensions can be used by clients for
enabling other behaviors/optimizations, such as TLS False Start.
This directive can be used to disable mod_tls' use of the ALPN/NPN
extensions as needed; see doc/contrib/mod_tls.html#TLSNextProtocol
for more details.
TLSPreSharedKey
Some sites may find that using pre-shared keys (PSK) is preferable
for their TLS needs. TLS clients in embedded or low power environments
may find PSK to be less computationally expensive. The mod_tls module
now supports pre-shared keys via its TLSPreSharedKey directive; see
doc/contrib/mod_tls.html#TLSPreSharedKey for details.
TransferOptions
There are some broken (e.g. old/mainframe) FTP clients that
will upload files, containing CRLF sequences, as ASCII data, but
these clients expect these CRLF sequences to be left as-is by the
FTP server. To handle these broken clients, there is a new
TransferOptions directive; see doc/modules/mod_xfer.html#TransferOptions
for more information.
+ Changed Configuration Directives
BanOnEvent BadProtocol
Some clients (malicious or unintentional) may send HTTP or SMTP commands
to ProFTPD. ProFTPD now detects these "bad protocol" messages, and
mod_ban can now ban clients that repeatedly do this via its BanOnEvent
rules. See doc/contrib/mod_ban.html#BanOnEvent for details.
DelayTable none
If the mod_delay module is used to enforce minimum delays, and not
use its DelayTable for "learning" the best delay, then the DelayTable
is not needed/used to all. The DelayTable directive can now be used
to tell mod_delay to not even open/lock on that table, using:
DelayTable none
See doc/modules/mod_delay.html#DelayTable.
DeleteAbortedStores
The DeleteAbortedStores directive, for Bug#3917, was meant to be
enabled, but only when HiddenStores was in effect. Unfortunately,
the fix caused a regression, as DeleteAbortedStores was enabled for
ALL transfers inadvertently. The desired behavior, of enabling
DeleteAbortedStores only when HiddenStores is in effect, has been
properly implemented now.
ExtendedLog
When an ExtendedLog is used for logging mod_sftp requests, the log
file will contain both the SFTP requests AND the internal FTP commands
to which mod_sftp will map the SFTP requests; this can lead to some
VERY verbose log files.
For greater control over SFTP logging, the ExtendedLog directive now
supports two new log classes: SSH, and SFTP. In addition, it supports
the '!' prefix, for excluding certain log classes from a given
ExtendedLog. For example:
LogFormat ftp "..." ALL,EXIT,!SSH,!SFTP
ExtendedLog /path/to/extended-ftp.log ftp
LogFormat sftp "..." SSH,SFTP
ExtendedLog /path/to/extended-sftp.log sftp
NOTE that existing ExtendedLogs that expect to see the SFTP requests will
no longer do so; adding the "SFTP" logging class to such ExtendedLogs is
now necessary.
HiddenStores
Some sites may experience HiddenStores filename collisions when
uploading FTP clients get disconnected, and/or use multiple concurrent
sessions for uploading. To help avoid collisions, the HiddenStores
directive now supports the %P variable, for adding the session PID
to the generated HiddenStore name.
In other cases, some sites may have FTP clients that want to use the
APPE FTP command, but cannot do so when HiddenStores is in effect.
These FTP clients are often outside of the site's control, and not
easily changed. ProFTPD now automatically disables the HiddenStores
functionality when an APPE FTP command is used; the APPE command
can only function on an existing file anyway, and thus there is no
loss of functionality with this policy change.
ListOptions
When ProFTPD generates a directory listing for FTP commands such as
LIST or NLST, it will automatically sort the names lexicographically.
For very wide directories, this can cause more memory/CPU usage, in
order to sort all of these names. This sorting can now be disabled
via ListOptions, using:
ListOptions -U
See doc/modules/mod_ls.html#ListOptions for more information.
SFTPDigests
The mod_sftp module now supports the umac-128@openssh.com MAC
algorithm; see doc/contrib/mod_sftp.html#SFTPDigests.
SFTPHostKey
Large hosting sites often use a section for centralizing
configuration of a large number of sections in their
proftpd.conf. Sometimes, such sites will want to disable use of
particular SSH hostkeys for a given . To support this
use case, the SFTPHostKey directive can be used to ignore any
globally-configured RSA, DSA, or ECDSA SSH hostkey, e.g.:
SFTPHostKey NoRSA
SFTPHostKey NoDSA
See doc/contrib/mod_sftp.html#SFTPHostKey for details.
SFTPOptions
Some OS distributions insist that their SSH hostkeys be group-readable.
In order to allow mod_sftp, which has more strict SSH hostkey permission
policies, to use those SSH hostkeys, the SFTPOptions directive can
now be used to relax this permission policy as needed:
SFTPOptions InsecureHostKeyPerms
See doc/contrib/mod_sftp.html#SFTPOptions for details.
Small Diffie-Hellman groups are subject to cryptographic weaknesses;
see https://weakdh.org. Thus mod_sftp now avoids the use of weak
DH groups by default; the AllowWeakDH SFTPOption is used to re-enable
such support for clients that require it.
See doc/contrib/mod_sftp.html#SFTPOptions.
SNMPAgent
Some sites may wish to have mod_snmp listening on multiple
addresses (e.g. on multi-homed servers), including IPv6 addresses.
The SNMPAgent directive now supports this, e.g.:
SNMPAgent master 127.0.0.1:1161 10.0.1.2:1161 [::]
See doc/contrib/mod_snmp.html#SNMPAgent for more information.
TLSOptions
Small Diffie-Hellman groups are subject to cryptographic weaknesses;
see https://weakdh.org. Thus mod_tls now avoids the use of weak
DH groups by default; the AllowWeakDH TLSOption is used to re-enable
such support for clients that require it.
See doc/contrib/mod_tls.html#TLSOptions.
+ Changed Command Handling
When handling the STAT FTP command, ProFTPD now follows RFC 959 more
closely, and will use the 213 response code for STAT commands on files,
and the 212 response code for STAT commands on directories. Previously,
ProFTPD would respond to all STAT commands using the 211 response code.
+ Changed Utilities
The ftpwho command-line utility can now emit its data as JSON,
for easier parsing/reuse in other utilities. To request JSON, use:
$ ftpwho -o json