This commit reverts the previous change to use system provided
entropy, as (SYS_)getrandom is very slow on Linux because it is
a syscall.
The change introduced in this commit adds a new call isc_nonce_buf
that uses CSPRNG from cryptographic library provider to generate
secure data that can be and must be used for generating nonces.
Example usage would be DNS cookies.
The isc_random() API has been changed to use fast PRNG that is not
cryptographically secure, but runs entirely in user space. Two
contestants have been considered xoroshiro family of the functions
by Villa&Blackman and PCG by O'Neill. After a consideration the
xoshiro128starstar function has been used as uint32_t random number
provider because it is very fast and has good enough properties
for our usage pattern.
The other change introduced in the commit is the more extensive usage
of isc_random_uniform in places where the usage pattern was
isc_random() % n to prevent modulo bias. For usage patterns where
only 16 or 8 bits are needed (DNS Message ID), the isc_random()
functions has been renamed to isc_random32(), and isc_random16() and
isc_random8() functions have been introduced by &-ing the
isc_random32() output with 0xffff and 0xff. Please note that the
functions that uses stripped down bit count doesn't pass our
NIST SP 800-22 based random test.
- mark the 'geoip-use-ecs' option obsolete; warn when it is used
in named.conf
- prohibit 'ecs' ACL tags in named.conf; note that this is a fatal error
since simply ignoring the tags could make ACLs behave unpredictably
- re-simplify the radix and iptable code
- clean up dns_acl_match(), dns_aclelement_match(), dns_acl_allowed()
and dns_geoip_match() so they no longer take ecs options
- remove the ECS-specific unit and system test cases
- remove references to ECS from the ARM
- Replace external -DOPENSSL/-DPKCS11CRYPTO with properly AC_DEFINEd
HAVE_OPENSSL/HAVE_PKCS11
- Don't enforce the crypto provider from platform.h, just from dst_api.c
and configure scripts
The three functions has been modeled after the arc4random family of
functions, and they will always return random bytes.
The isc_random family of functions internally use these CSPRNG (if available):
1. getrandom() libc call (might be available on Linux and Solaris)
2. SYS_getrandom syscall (might be available on Linux, detected at runtime)
3. arc4random(), arc4random_buf() and arc4random_uniform() (available on BSDs and Mac OS X)
4. crypto library function:
4a. RAND_bytes in case OpenSSL
4b. pkcs_C_GenerateRandom() in case PKCS#11 library
Certain isc_buffer_*() functions might call memmove() with the second
argument (source) set to NULL and the third argument (length) set to 0.
While harmless, it triggers an ubsan warning:
runtime error: null pointer passed as argument 2, which is declared to never be null
Modify all memmove() call sites in lib/isc/include/isc/buffer.h and
lib/isc/buffer.c which may potentially use NULL as the second argument
(source) so that memmove() is only called if the third argument (length)
is non-zero.
4807. [cleanup] isc_rng_randombytes() returns a specified number of
bytes from the PRNG; this is now used instead of
calling isc_rng_random() multiple times. [RT #46230]
4768. [func] By default, memory is no longer filled with tag values
when it is allocated or freed; this improves
performance but makes debugging of certain memory
issues more difficult. "named -M fill" turns memory
filling back on. (Building "configure
--enable-developer", turns memory fill on by
default again; it can then be disabled with
"named -M nofill".) [RT #45123]
4762. [func] "update-policy local" is now restricted to updates
from local addresses. (Previously, other addresses
were allowed so long as updates were signed by the
local session key.) [RT #45492]
4724. [func] By default, BIND now uses the random number
functions provided by the crypto library (i.e.,
OpenSSL or a PKCS#11 provider) as a source of
randomness rather than /dev/random. This is
suitable for virtual machine environments
which have limited entropy pools and lack
hardware random number generators.
This can be overridden by specifying another
entropy source via the "random-device" option
in named.conf, or via the -r command line option;
however, for functions requiring full cryptographic
strength, such as DNSSEC key generation, this
cannot be overridden. In particular, the -r
command line option no longer has any effect on
dnssec-keygen.
This can be disabled by building with
"configure --disable-crypto-rand".
[RT #31459] [RT #46047]
4708. [cleanup] Legacy Windows builds (i.e. for XP and earlier)
are no longer supported. [RT #45186]
4707. [func] The lightweight resolver daemon and library (lwresd
and liblwres) have been removed. [RT #45186]
4706. [func] Code implementing name server query processing has
been moved from bin/named to a new library "libns".
Functions remaining in bin/named are now prefixed
with "named_" rather than "ns_". This will make it
easier to write unit tests for name server code, or
link name server functionality into new tools.
[RT #45186]
4579. [func] Logging channels and dnstap output files can now
be configured with a "suffix" option, set to
either "increment" or "timestamp", indicating
whether to use incrementing numbers or timestamps
as the file suffix when rolling over a log file.
[RT #42838]
4518. [func] The "print-time" option in the logging configuration
can now take arguments "local", "iso8601" or
"iso8601-utc" to indicate the format in which the
date and time should be logged. For backward
compatibility, "yes" is a synonym for "local".
[RT #42585]
4503. [cleanup] "make uninstall" now removes file installed by
BIND. (This currently excludes Python files
due to lack of support in setup.py.) [RT #42912]
4445. [cleanup] isc_errno_toresult() can now be used to call the
formerly private function isc__errno2result().
[RT #43050]
4444. [bug] Fixed some issues related to dyndb: A bug caused
braces to be omitted when passing configuration text
from named.conf to a dyndb driver, and there was a
use-after-free in the sample dyndb driver. [RT #43050]
Patch for dyndb driver submitted by Petr Spacek at Red Hat.
4411. [func] "rndc dnstap -roll" automatically rolls the
dnstap output file; the previous version is
saved with ".0" suffix, and earlier versions
with ".1" and so on. An optional numeric argument
indicates how many prior files to save. [RT #42830]
provisioning secondary servers in which a list of
zones to be served is stored in a DNS zone and can
be propagated to slaves via AXFR/IXFR. [RT #41581]
4375. [func] Add support for automatic reallocation of isc_buffer
to isc_buffer_put* functions. [RT #42394]
4235. [func] Added support in named for "dnstap", a fast method of
capturing and logging DNS traffic, and a new command
"dnstap-read" to read a dnstap log file. Use
"configure --enable-dnstap" to enable this
feature (note that this requires libprotobuf-c
and libfstrm). See the ARM for configuration details.
Thanks to Robert Edmonds of Farsight Security.
[RT #40211]
4224. [func] Added support for "dyndb", a new interface for loading
zone data from an external database, developed by
Red Hat for the FreeIPA project.
DynDB drivers fully implement the BIND database
API, and are capable of significantly better
performance and functionality than DLZ drivers,
while taking advantage of advanced database
features not available in BIND such as multi-master
replication.
Thanks to Adam Tkac and Petr Spacek of Red Hat.
[RT #35271]
4183. [cleanup] Use timing-safe memory comparisons in cryptographic
code. Also, the timing-safe comparison functions have
been renamed to avoid possible confusion with
memcmp(). [RT #40148]
3938. [func] Added quotas to be used in recursive resolvers
that are under high query load for names in zones
whose authoritative servers are nonresponsive or
are experiencing a denial of service attack.
- "fetches-per-server" limits the number of
simultaneous queries that can be sent to any
single authoritative server. The configured
value is a starting point; it is automatically
adjusted downward if the server is partially or
completely non-responsive. The algorithm used to
adjust the quota can be configured via the
"fetch-quota-params" option.
- "fetches-per-zone" limits the number of
simultaneous queries that can be sent for names
within a single domain. (Note: Unlike
"fetches-per-server", this value is not
self-tuning.)
- New stats counters have been added to count
queries spilled due to these quotas.
See the ARM for details of these options. [RT #37125]
experimental SIT option of BIND 9.10. The following
named.conf directives are avaliable: send-cookie,
cookie-secret, cookie-algorithm and nocookie-udp-size.
The following dig options are available:
+[no]cookie[=value] and +[no]badcookie. [RT #39928]
4005. [func] The buffer used for returning text from rndc
commands is now dynamically resizable, allowing
arbitrarily large amounts of text to be sent back
to the client. (Prior to this change, it was
possible for the output of "rndc tsig-list" to be
truncated.) [RT #37731]
3999. [func] "mkeys" and "nzf" files are now named after
their corresponding views, unless the view name
contains characters that would be incompatible
with use in a filename (i.e., slash, backslash,
or capital letters). If a view name does contain
these characters, the files will still be named
using a cryptographic hash of the view name.
Regardless of this, if a file using the old name
format is found to exist, it will continue to be
used. [RT #37704]
startup-notify-rate instead of serial-query-rate.
[RT #24454]
3955. [bug] Notify messages due to changes are no longer queued
behind startup notify messages. [RT #24454]
3936. [func] Added authoritative support for the EDNS Client
Subnet (ECS) option.
ACLs can now include "ecs" elements which specify
an address or network prefix; if an ECS option is
included in a DNS query, then the address encoded
in the option will be matched against "ecs" ACL
elements.
Also, if an ECS address is included in a query,
then it will be used instead of the client source
address when matching "geoip" ACL elements. This
behavior can be overridden with "geoip-use-ecs no;".
When "ecs" or "geoip" ACL elements are used to
select a view for a query, the response will include
an ECS option to indicate which client network the
answer is valid for.
(Thanks to Vincent Bernat.) [RT #36781]
No CHANGES entry was added as this commit mainly adds tests related
code.
Squashed commit of the following:
commit d3d44508daa128fb8b60f64b3a8c81f80602273d
Author: Evan Hunt <each@isc.org>
Date: Wed May 7 09:36:41 2014 -0700
[rt35904] remove private non-static names from .def file
commit dbca45661c3939f21c3bb3f405d08cfe1b35d7aa
Author: Mukund Sivaraman <muks@isc.org>
Date: Wed May 7 21:39:32 2014 +0530
Remove test for shortcut findnode()
The implementation was not included in this review branch, but the tests
erroneously made it through.
This functionality will be addressed in a different ticket (RT#35906).
commit 94ff14576ab3407f2612d34727b7eacfefc3668c
Author: Mukund Sivaraman <muks@isc.org>
Date: Wed May 7 21:36:50 2014 +0530
Minor indent fix
commit 50972f17697bb222996e433faa8224843366f9b2
Author: Evan Hunt <each@isc.org>
Date: Tue May 6 20:05:21 2014 -0700
[rt35904] style
commit 5c4d5d41fcc5bfecdeebc008896974385c841b8d
Author: Mukund Sivaraman <muks@isc.org>
Date: Sun May 4 19:19:36 2014 +0530
RBT related updates
* Add various RBT unit tests
* Add some helper methods useful in unit testing RBT code
* General cleanup
3786. [func] Provide more detailed error codes when using
native PKCS#11. "pkcs11-tokens" now fails robustly
rather than asserting when run against an HSM with
an incomplete PCKS#11 API implementation. [RT #35479]
3760. [bug] Improve SIT with native PKCS#11 and on Windows.
[RT #35433]
3759. [port] Enable delve on Windows. [RT #35441]
3758. [port] Enable export library APIs on windows. [RT #35382]
(which are similar to DNS Cookies by Donald Eastlake)
and are designed to help clients detect off path
spoofed responses and for servers to detect legitimate
clients.
SIT use a experimental EDNS option code (65001).
SIT can be enabled via --enable-developer or
--enable-sit. It is on by default in Windows.
RRL processing as been updated to know about SIT with
legitimate clients not being rate limited. [RT #35389]
3741. [func] "delve" (domain entity lookup and validation engine):
A new tool with dig-like semantics for performing DNS
lookups, with internal DNSSEC validation, using the
same resolver and validator logic as named. This
allows easy validation of DNSSEC data in environments
with untrustworthy resolvers, and assists with
troubleshooting of DNSSEC problems. (Note: not yet
available on win32.) [RT #32406]
