The key lifetime should not be shorter than the time it costs to
introduce the successor key, otherwise keys will be created faster than
they are removed, resulting in a large key set.
The time it takes to replace a key is determined by the publication
interval (Ipub) of the successor key and the retire interval of the
predecessor key (Iret).
For the ZSK, Ipub is the sum of the DNSKEY TTL and zone propagation
delay (and publish safety). Iret is the sum of Dsgn, the maximum zone
TTL and zone propagation delay (and retire safety). The sign delay is
the signature validity period minus the refresh interval: The time to
ensure that all existing RRsets have been re-signed with the new key.
The ZSK lifetime should be larger than both values.
For the KSK, Ipub is the sum of the DNSKEY TTL and zone propagation
delay (and publish safety). Iret is the sum of the DS TTL and parent
zone propagation delay (and retire safety). The KSK lifetime should be
larger than both values.
(cherry picked from commit 8134d46cdb)
The signatures-refresh should not near the signatures-validity value,
to prevent operational instability. Same is true when checking against
signatures-validity-dnskey.
(cherry picked from commit 82fd89107f)
bad-ksk-without-zsk.conf only has a ksk defined without a
matching zsk for the same algorithm.
bad-zsk-without-ksk.conf only has a zsk defined without a
matching ksk for the same algorithm.
bad-unpaired-keys.conf has two keys of different algorithms
one ksk only and the other zsk only
(cherry picked from commit f23e86b96b)
This commit converts the license handling to adhere to the REUSE
specification. It specifically:
1. Adds used licnses to LICENSES/ directory
2. Add "isc" template for adding the copyright boilerplate
3. Changes all source files to include copyright and SPDX license
header, this includes all the C sources, documentation, zone files,
configuration files. There are notes in the doc/dev/copyrights file
on how to add correct headers to the new files.
4. Handle the rest that can't be modified via .reuse/dep5 file. The
binary (or otherwise unmodifiable) files could have license places
next to them in <foo>.license file, but this would lead to cluttered
repository and most of the files handled in the .reuse/dep5 file are
system test files.
This sets as many server options as possible at once to detect
cut-and-paste bugs when implementing new server options in peer.c.
Most of the accessor functions are similar and it is easy to miss
updating a macro name or structure element name when adding new
accessor functions.
checkconf/setup.sh is there to minimise the difference to branches
with optional server options where the list is updated at runtime.
This commit ensure that the 'tls' name specified in the 'primaries'
clause of a 'zone' statement is a valid one.
Prior to that such a name would be silently accepted, leading to
silent XFRs-via-TLS failures.
This commit extends the 'doth' system test to verify that the new
extended 'allow-transfer' option syntax featuring 'port' and
'transport' parameters is supported and works as expected. That is, it
restricts the primary server to allow zone transfers only via XoT.
Additionally to that, it extends the 'checkonf' test with more
configuration file examples featuring the new syntax.
This commit disables the unused 'tls' clause options. For these some
backing code exists, but their values are not really used anywhere,
nor there are sufficient syntax tests for them.
These options are only disabled temporarily, until TLS certificate
verification gets implemented.
In the 9.17.19 release "tls" statements verification code was
added. The code was too strict and assumed that every such a statement
should have both "cert-file" and "key-file" specified. This turned out
to be a regression, as in some cases we plan to use the "tls"
statement to specify TLS connection parameters.
This commit fixes this behaviour; now a "tls" statement should either
have both "cert-file" and "key-file" specified, or both should be
omitted.
Duplicate catalog zone entries caused an assertion failure
in named during configuration. This is now a soft error
that is detected earlier by named and also by named-checkconf.
Replace most "master/slave" terminology in tests with the preferred
"primary/secondary", with the following exceptions:
- When testing the old syntax
- When master is used in master file and master file format terms
- When master is used in hostmaster or postmaster terms
- When master used in legacy domain names (for example in dig.batch)
- When there is no replacement (for example default-masters)
This commit adds the ability to enable or disable stateless TLS
session resumption tickets (see RFC5077). Having this ability is
twofold.
Firstly, these tickets are encrypted by the server, and the algorithm
might be weaker than the algorithm negotiated during the TLS session
establishment (it is in general the case for TLSv1.2, but the generic
principle applies to TLSv1.3 as well, despite it having better ciphers
for session tickets). Thus, they might compromise Perfect Forward
Secrecy.
Secondly, disabling it might be necessary if the same TLS key/cert
pair is supposed to be used by multiple servers to achieve, e.g., load
balancing because the session ticket by default gets generated in
runtime, while to achieve successful session resumption ability, in
this case, would have required using a shared key.
The proper alternative to having the ability to disable stateless TLS
session resumption tickets is to implement a proper session tickets
key rollover mechanism so that key rotation might be performed
often (e.g. once an hour) to not compromise forward secrecy while
retaining the associated performance benefits. That is much more work,
though. On the other hand, having the ability to disable session
tickets allows having a deployable configuration right now in the
cases when either forward secrecy is wanted or sharing the TLS
key/cert pair between multiple servers is needed (or both).
This commit adds support for enforcing the preference of server
ciphers over the client ones. This way, the server attains control
over the ciphers priority and, thus, can choose more strong cyphers
when a client prioritises less strong ciphers over the more strong
ones, which is beneficial when trying to achieve Perfect Forward
Secrecy.
This commit adds support for setting TLS cipher list string in the
format specified in the OpenSSL
documentation (https://www.openssl.org/docs/man1.1.1/man1/ciphers.html).
The syntax of the cipher list is verified so that specifying the wrong
string will prevent the configuration from being loaded.
This commit adds support for loading DH-parameters (Diffie-Hellman
parameters) via the new "dhparam-file" option within "tls" clause. In
particular, Diffie-Hellman parameters are needed to enable the range
of forward-secrecy enabled cyphers for TLSv1.2, which are getting
silently disabled otherwise.
This commit adds the ability to specify allowed TLS protocols versions
within the "tls" clause. If an unsupported TLS protocol version is
specified in a file, the configuration file will not pass
verification.
Also, this commit adds strict checks for "tls" clauses verification,
in particular:
- it ensures that loading configuration files containing duplicated
"tls" clauses is not allowed;
- it ensures that loading configuration files containing "tls" clauses
missing "cert-file" or "key-file" is not allowed;
- it ensures that loading configuration files containing "tls" clauses
named as "ephemeral" or "none" is not allowed.
This commit fixes heap use after free when checking BIND's
configuration files for errors with http clauses. The old code
was unnecessarially copying the http element name and freeing
it to early. The name is now used directly.
- when transfer-source(-v6), query-source(-v6), notify-source(-v6)
or parental-source(-v6) are specified with a port number, issue a
warning.
- when the port specified is the same as the DNS listener port (i.e.,
53, or whatever was specified as "port" in "options"), issue a fatal
error.
- check that "port" is in range. (previously this was only checked
by named, not by named-checkconf.)
- added checkconf tests.
- incidental fix: removed dead code in check.c:bind9_check_namedconf().
(note: if the DNS port is specified on the command line with "named -p",
that is not conveyed to libbind9, so these checks will not take it into
account.)
This commit makes number of concurrent HTTP/2 streams per connection
configurable as a mean to fight DDoS attacks. As soon as the limit is
reached, BIND terminates the whole session.
The commit adds a global configuration
option (http-streams-per-connection) which can be overridden in an
http <name> {...} statement like follows:
http local-http-server {
...
streams-per-connection 100;
...
};
For now the default value is 100, which should be enough (e.g. NGINX
uses 128, but it is a full-featured WEB-server). When using lower
numbers (e.g. ~70), it is possible to hit the limit with
e.g. flamethrower.
This commit adds support for http-listener-clients global options as
well as ability to override the default in an HTTP server description,
like:
http local-http-server {
...
listener-clients 100;
...
};
This way we have ability to specify per-listener active connections
quota globally and then override it when required. This is exactly
what AT&T requested us: they wanted a functionality to specify quota
globally and then override it for specific IPs. This change
functionality makes such a configuration possible.
It makes sense: for example, one could have different quotas for
internal and external clients. Or, for example, one could use BIND's
internal ability to serve encrypted DoH with some sane quota value for
internal clients, while having un-encrypted DoH listener without quota
to put BIND behind a load balancer doing TLS offloading for external
clients.
Moreover, the code no more shares the quota with TCP, which makes
little sense anyway (see tcp-clients option), because of the nature of
interaction of DoH clients: they tend to keep idle opened connections
for longer periods of time, preventing the TCP and TLS client from
being served. Thus, the need to have a separate, generally larger,
quota for them.
Also, the change makes any option within "http <name> { ... };"
statement optional, making it easier to override only required default
options.
By default, the DoH connections are limited to 300 per listener. I
hope that it is a good initial guesstimate.
This commit adds the code (and some tests) which allows verifying
validity of HTTP paths both in incoming HTTP requests and in BIND's
configuration file.
This commit adds two new autoconf options `--enable-doh` (enabled by
default) and `--with-libnghttp2` (mandatory when DoH is enabled).
When DoH support is disabled the library is not linked-in and support
for http(s) protocol is disabled in the netmgr, named and dig.
Add checks for "parental-agents" configuration, checking for the option
being at wrong type of zone (only allowed for primaries and
secondaries), duplicate definitions, duplicate references, and
undefined parental clauses (the name referenced in the zone clause
does not have a matching "parental-agent" clause).
Add three more test cases that detect a configuration error if the
key-directory is inherited but has the same value for a zone in a
different view with a deviating DNSSEC policy.
Add two tests to make sure named-checkconf catches key-directory issues
where a zone in multiple views uses the same directory but has
different dnssec-policies. One test sets the key-directory specifically,
the other inherits the default key-directory (NULL, aka the working
directory).
Also update the good.conf test to allow zones in different views
with the same key-directory if they use the same dnssec-policy.
Also allow zones in different views with different key-directories if
they use different dnssec-policies.
Also allow zones in different views with the same key-directories if
only one view uses a dnssec-policy (the other is set to "none").
Also allow zones in different views with the same key-directories if
no views uses a dnssec-policy (zone in both views has the dnssec-policy
set to "none").
Just like with dynamic and/or inline-signing zones, check if no two
or more zone configurations set the same filename. In these cases,
the zone files are not read-only and named-checkconf should catch
a configuration where multiple zone statements write to the same file.
Add some bad configuration tests where KASP zones reference the same
zone file.
Update the good-kasp test to allow for two zones configure the same
file name, dnssec-policy none.
When reducing the number of NSEC3 iterations to 150, commit
aa26cde2ae added tests for dnssec-policy
to check that a too high iteration count is a configuration failure.
The test is not sufficient because 151 was always too high for
ECDSAP256SHA256. The test should check for a different algorithm.
There was an existing test case that checks for NSEC3 iterations.
Update the test with the new maximum values.
Update the code in 'kaspconf.c' to allow at most 150 iterations.
Matthijs Mekking
Artem Boldariev
Mark Andrews
Ondřej Surý
Ondřej Surý
Aram Sargsyan