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.
