Forum OpenACS Development: Announcement: NaviServer 4.99.24 available

Dear all,

I am pleased to announce the availability of NaviServer 4.99.24 [1,2]. This release contains various fixes and enhancements. In short, it contains improved security features (reject invalid UTF-8), fallback charsets, Cookie support avoiding potential problems with more restrictive browsers, better network filtering support, improved Oracle support for new Oracle versions, etc.

The summary of changes is listed below. This release was tested with Ubuntu 20.04, Rocky Linux 8.5, FreeBSD 13.0, macOS 11.6.6.

The following people have contributed to this release:

Antonio Pisano
David Osborne
Gustaf Neumann
Zoran Vasiljevic

Many thanks to all contributors!

The upgrade to 4.99.24 is recommended. The installation script install-ns is updated to point to the new version.

-gustaf neumann
[1] https://sourceforge.net/projects/naviserver/files/naviserver/4.99.24/
[2] https://bitbucket.org/naviserver/naviserver/

=======================================
NaviServer 4.99.24, released 2022-06-14
=======================================

77 files changed, 3242 insertions(+), 1100 deletions(-)

New Features:

- Improved security

* Added protection against certain attacks in ns_dbquotevalue

Due to the corrected conversion to external UTF-8 in db-output,
new potential attack vectors appeared that were protected earlier
via the Tcl-internal 'modified UTF-8'. E.g., the binary null
character is stored as an overlong (two-byte) encoding of null
(0xc0 0x80), so that an actual (embedded) null byte (0x00) never
appears in the string. Due to the conversion, the internal
representation is translated back to the binary null
character. Embedded null byte characters can lead to
non-terminated string literals via ns_dbquotevalue.

In the updated version of NaviServer, ns_dbquotevalue raises an
exception when this occurs. Therefore, the function can be used
as well as an input checker (together with "try").

* Raise an exception when trying to use "ns_urldecode" to
produce invalid UTF-8

Background: several (external) functions expect valid UTF-8 to be
passed in and crash if this is not the case. One such example is
tDOM. These nasty byte sequences are used more intensively by
vulnerability scanners.

Therefore, ns_urldecode raises now an exception, when it tries to
convert to invalid UTF-8. It is still possible to use
ns_urldecode to convert to other charsets.

ns_urldecode -charset iso8859-1 -part path "/mot%C3or"

When urldecode() is called internally and would produce invalid
UTF-8, it truncates the string (and writes a warning to the
system log).

Note that the new fallback charset feature might avoid such
exceptions (see below).

- Fallback charsets

In case, a conversion to UTF-8 fails due to invalid byte sequences,
one can now provide a fallback charset for a second attempt of
decoding this data. This feature is useful for websites that
have to deal with requests containing invalid (form) data, typically
from legacy applications.

The fallback charset can be provided as optional parameter
"-fallbackcharset" for the command "ns_getform", "ns_parsequery"
and "ns_urldecode":

ns_getform ?-fallbackcharset fallbackcharset? ?charset?
ns_parsequery ?-charset charset? ?-fallbackcharset fallbackcharset? ?--? querystring
ns_urldecode ?-charset charset? ?-fallbackcharset fallbackcharset? ?-part part? ?--? string

In case, the parameter is not specified, it can be also be provided
to the form-processing commands "ns_getform" and "ns_parsequery" via
configuration variables:

* per-server configuration parameter "formFallbackCharset"
(in the section "ns/server/$server"), or as

* global server configuration parameter "formFallbackCharset"
(in the section "ns/parameters").

The highest precedence has the optional parameter, followed by the
per-server configuration parameter and the global configuration
parameter.

- Provide a hint when cache-entry is too large for caching

Background: the size of the entry is typically determined after the
execution of a potentially expensive query. During the eval of the
command, the cache entry is locked and forces a
serialization. However, this means that in these cases the
situation is worse than without a cache, where some queries can be
executed in parallel. We faced the situation of an expected
slowdown of the server with many "create entry collision", where
due to application matters, an entry was becoming too large. This
situation is not easy to debug, especially in stress
situations. The log message would have helped a log to identify the
cause.

- Added support for multibyte numeric entities

This change supports conversion of numeric entities representing
multibyte characters into HTML in "ns_striphtml" and
"ns_unquotehtml". Technically, the numeric entities represent
Unicode code points, which are transformed into UTF-8
serialization. Every entity represents a single code point; The
values can be provided in decimal or hexadecimal notation. Before
this change, only single byte numeric entities were
supported. ASCII control characters (decimal 0-31) are ignored as
before.

- New and extended commands:

* ns_unquotehtml /text/

This command is the inverse operation of "ns_quotehtml". It
replaces the named and numeric entities in the provided string
with the native values. The command is similar to "ns_striphtml",
but "ns_striphtml" removes as well other HTML markup which might
not be desired in all cases.

This change fixes as well a bug with numeric entities (the old
code assumed, these are starting directly with a number after the
ampersand) and it adds support for numeric entities with
hexadecimal values (so far with the same value range as for
decimal numeric entities).

* ns_subnetmatch /subnet/ /ipaddr/

Determine, if a provided IP address (IPv4 or IPv6) is included in
a subnet specification, which is provided in CIDR notation. The
command makes internal NaviServer functionality available at the
Tcl level. The regression test was extended to cover the
functionality.

The command ns_subnetmatch validates the provided subnet
specification (IPv4 or IPv6 address followed by slash and number
of significant bits) and the provided IP address and tests whether
the IP address is in the implied range. The command returns a
boolean value as the result. When comparing an IPv4 and IPv6
address/CIDR specification or vice versa, the result is always
false.

The function can be use when e.g. restricting access to certain
functionality to some subnets. The function can be used as well
to check, whether an IP address is an IPv4 or IPv6 address.

Examples:
% ns_subnetmatch 137.208.0.0/16 137.208.116.31
1

% ns_subnetmatch 137.208.0.0/16 112.207.16.33
0

% ns_subnetmatch 2001:628:404:74::31/64 [ns_conn peeraddr]
...

# Is IP address a valid IPv6 address?
% ns_subnetmatch ::/0 $ip

# Is IP address a valid IPv4 address?
% ns_subnetmatch 0.0.0.0/0 $ip

* ns_connchan: Added new subcommand "ns_connchan connect"

"ns_connchan connect" is similar to "ns_connchan open", except
that it does not send an HTTP request (HTTP method, URL, and
header fields) but just opens the connection. It can be used for
some non-HTTP communication over TCP and TLS over the ns_connchan
infrastructure.

* ns_parseheader, Ns_ParseHeader(): return the field
number (index) of the parsed entry

Previously, there was no explicit feedback, what field of an
"ns_set" has been parsed by "ns_parseheader". Now, in success
cases, the function returns the index of the new/modified
entry. This function made it possible to generalize and simplify
the Tcl-level parsing of "multipart/form-data"
significantly. Additionally, a new optional argument "-prefix"
was added. When specified, it adds the specified prefix to the
key.

* ns_setcookie, ns_deletecookie

Mozilla and Chrome changed the default value for SameSite of
cookies from "none" to "lax" in February and Aug 2020. Cookies
that explicitly set SameSite=None must also set the "Secure"
attribute.

In order to mirror this change of policy in NaviServer and to
reduce necessary code changes, the default behavior for setting
or deleting cookie is now samesite "lax" (when "-samesite" is not
explicitly specified). When trying to set a cookie with
"-samesite none" without the "-secure" flag, a warning is
generated, and the "-samesite lax" is assumed, since major
browsers announced that these will reject these cookies soon.

API changes:

- ns_getform, ns_parsequery, and ns_urldecode

New optional parameter "-fallbackcharset". See above for details.

- ns_parsequery: added option "-charset" and raise exception on failure

The new option "-charset" can be used to add a charset for the
result encoding of the passed-in HTTP query.

In case the charset is UTF8 (default on most platforms), and the
content is invalid UTF-8, an exception is raised (similar to
ns_urldecode). This can be addressed by parameter
"-fallbackcharset" (See above for details).

- ns_deletecookie: added support "-samesite" flag for ns_deletecookie.

Since "ns_deletecookie" sets internally a cookie, some browsers
might ignore in the future certain cookie requests (e.g. when
"-samesite" is not used or set to "none" on non-secure connections).

- ns_trim enhancements:
The new option "-prefix ..." can be used to strip a string
(such as ">> ") from every line starting with it.

- Potential incompatibilities
* "ns_urldecode" and "ns_getform" will raise an exception
when invalid UTF-8 data is tried to be interpreted as UTF-8
and no fallback charset is provided. Invalid UTF-8 data
causes trouble with external components such as
Tdom or databases and opens vulnerability vectors.

Performance Improvements:

- Improve "cachingmode none"

"ns_cache_eval" works as follows:
1) create a temporary cache entry for the key
2) lock the cache-key (to avoid multiple parallel executions)
3) execute the query
4) store the result for the entry on success
5) unlock the cache-key

Previously, "cachingmode none" was simply avoiding to store the cached
values (step 4), but was serializing calls for a cache key as in
default caching modes. This was leading easily to cache entry collisions.

Now, "cachingmode none" is avoiding all steps 1..5 (therefore
no serialization and no cache collisions).

See also: https://openacs.org/forums/message-view?message_id=5665480

Bug Fixes:

- Improved robustness of "ns_parseurl" for handling query parameters
and fragments for partial URLs

* fix over-eager collecting of URL components in tail
* extended regression test

- Fixed Ns_ResetFileVec NOT to invalidate residual Ns_FileVec
buffer.q (caused problems under Windows).

- ns_striphtml: Fixed probably very old bug for markup immediately
after an entity

This bug fix handles cases, where e.g. two entities are in a text
right next to each other, like e.g. in the string
"hello<>world". The old code was correctly decoding the
first entity, but output the second one literally.

- Fixed compilation for C++, which was introduced in 4.99.23
to avoid usage of reserved C identifiers

Many thanks to Brendan Graves for reporting the problem.

- Added missing named entities "apos" and "quote". These have been
missing since ages.

- Provide an error message when the configured locale is not
installed on the host.

This change causes NaviServer to abort, when the configured locale
is not installed on the host. Typically, this locale is e.g. used
by "ns_strcoll" for determining the default collating order. The
configuration file for the regression testing sets the environment
variable LANG to "en_US.UTF-8". This means that for running the
stock regression test, this locale must be installed on the
system. Before this change, NaviServer could crash at runtime when
trying to access the default locale (as e.g. in "ns_strcoll")

- Added support for "_charset_" field for default charset in
multipart/form-data (RFC 7578, section 4.6)

RFC 7578 (July 2015) defines an optional "_charset_" entry in the
form (typically provided as hidden form field) to specify the
charset of text entries. This is now supported as well by
NaviServer. This is apparently a seldom used feature.

Documentation improvements:
---------------------------

- Improved the following man pages:

doc/src/manual/admin-install.man
doc/src/naviserver/ns_conn.man
doc/src/naviserver/ns_connchan.man
doc/src/naviserver/ns_cookie.man
doc/src/naviserver/ns_crypto.man
doc/src/naviserver/ns_getform.man
doc/src/naviserver/ns_http.man
doc/src/naviserver/ns_httptime.man
doc/src/naviserver/ns_log.man
doc/src/naviserver/ns_parseheader.man
doc/src/naviserver/ns_parsequery.man
doc/src/naviserver/ns_parseurl.man
doc/src/naviserver/ns_rlimit.man
doc/src/naviserver/ns_urldecode.man
doc/src/naviserver/ns_urlencode.man
doc/src/naviserver/ns_valid_utf8.man
doc/src/naviserver/textutil-cmds.man
nsdb/doc/mann/ns_db.man

Configuration Changes:
----------------------

- Updated OpenACS sample configuration file
* reflect recent Oracle (tested with Oracle 19c)

* added documentation for "StaticCSP", "CookieNamespace",
"NsShutdownWithNonZeroExitCode", "LogIncludeUserId"

Code Changes:
-------------

- Set Tcl error code "NS_INVALID_UTF8" for errors due to invalid UTF-8

- Changed Tcl error code "NSCACHE" to "NS_CACHE". Now all
NaviServer-specific error codes start with the prefix "NS_".

- Extended regression test

- Improve Tcl version compatibility

* Removed -DTCL_NO_DEPRECATED from default CFLAGS to cope with
recent deprecation in Tcl 8.7a5

- Code Cleanup
. Do not declare reserved C identifiers
. Improved type cleanness
. Refactored file-based multipart form parser to make logic
explicit (Tcl code)

- Improved comments, fixed typos

- Marked "ns_set_precision" as deprecated, since there is no
reason why not setting the Tcl variable ::tcl_precision directly.

- Don't hard-wire port for HTTPS testing to 8443

The setup code looks now for a free port for HTTPS connections
starting with 8443, and remembers the free port in the
configuration value "tls_listenport" and "tls_listenurl". This is
now fully analogous to the setup of the plain HTTP testing (setting
"listenport" and "listenurl")

- Silence warning with recent versions of gcc when certain values of
_FORTIFY_SOURCE/-Wstringop-overflow are set.

Changes in NaviServer Modules:
==============================

22 files changed, 8447 insertions(+), 1429 deletions(-)

- general: Updated obsolete ChangeLog files and
replaced these by automatically generated ones.

nsdbpg:
-------

- Raise exception when a value for a bind variable contains a NUL
character. This value is explicitly forbidden in text strings
passed to PostgreSQL.

- Let "ns_pg" report available subcommands even when handle is not
specified. This makes the command compatible with the "icanuse"
feature in OpenACS.

nsoracle:
---------
- Added support for output columns of type SQLT_TIMESTAMP or SQLT_TIMESTAMP_TZ

This change fixes a bug, where SQL queries of the form

SELECT TO_TIMESTAMP(sysdate) FROM dual

lead to errors for the form:

Database operation "getrow" failed (exception 1406, "nsoracle.c:3659:Ns_OracleGetRow:
error in `OCIStmtFetch ()': ORA-01406: fetched column value was truncated

The driver needs for several output types special rules, where the
timestamp cases were not supported so far. It is also recommended
to set the according environment variables specifying the output
format in the configuration server of NaviServer, such as e.g.

set ::env(NLS_TIMESTAMP_FORMAT) "YYYY-MM-DD HH24:MI:SS.FF6"
set ::env(NLS_TIMESTAMP_TZ_FORMAT) "YYYY-MM-DD HH24:MI:SS.FF6 TZH:TZM"

For testing in you local Oracle installation, you might test the
output formats (and the required sizes with the following snippet
for sqlplus:

COLUMN localtimestamp format a40
COLUMN systimestamp format a40
COLUMN ts_bytes format a80

alter session set nls_timestamp_format='YYYY-MM-DD HH24:MI:SS.FF6';
select localtimestamp, length(localtimestamp), dump(localtimestamp) ts_bytes from dual;

alter session set nls_timestamp_tz_format='YYYY-MM-DD HH24:MI:SS.FF6 TZH:TZM';
select systimestamp, length(systimestamp), dump(systimestamp) ts_bytes from dual;

alter session set nls_timestamp_tz_format='YYYY-MM-DD HH24:MI:SS.FF6 TZR';
select systimestamp, length(systimestamp), dump(systimestamp) ts_bytes from dual;

- Code cleanup, ensure silent compilation with standard compiler settings
- Improved spelling

ECDSA
letsencrypt:
------------
- Added option to produce certificates with ECDSA

Prior to this change, all certificates were using RSA keys. Since a
while, keys based on elliptic curves became the preference of
letsencrypt.

- Improved spelling