CLEANUP is a macro similar to CHECK but unconditional, jumping
to cleanup even if the result is ISC_R_SUCCESS. It is now used
in place of DST_RET, CLEANUP_WITH, and CHECK(<non-success constant>).
now that the EDNS state is stored within dns_message_t, it's no longer
necessary to have a public API call to build an opt rdataset; we can
just have dns_message_setopt() build the opt record internally.
The new dns_message_ednsinit() and dns_message_ednsaddopt() functions
allow EDNS options to be added to a message one at a time; it is no
longer necessary to construct a full array of EDNS options and set
them all at once.
This allows us to simplify EDNS option handling code, and in the
future it wlil allow plugins to add EDNS options to existing
messages.
To prevent spoofed unsigned DNAME responses being accepted retry
response with unsigned DNAMEs over TCP if the response is not TSIG
signed or there isn't a good DNS CLIENT COOKIE.
Mimic the Unbound behaviour where the cyclic offset is taken from query
ID, and remove recording of the current state. As the incoming query ID
should have random distribution, the cyclic ordering should also have
uniform distribution of the starting record.
> Put a space before opening parentheses only after control statement
> keywords (for/if/while...) except this option doesn’t apply to ForEach
> and If macros. This is useful in projects where ForEach/If macros are
> treated as function calls instead of control statements.
Use dns_rdatatype_none instead of plain '0' for dns_rdatatype_t and
dns_typepair_t manipulation. While plain '0' is technically ok, it
doesn't carry the required semantic meaning, and using the named
dns_rdatatype_none constant makes the code more readable.
RRset ordering is now an enum inside struct rdataset attributes. This
was done to keep size to of the structure to its original value before
this MR.
I expect zero performance impact but it should be easier to deal with
attributes in debuggers and language servers.
Instead of giving the memory pools names with an explicit call to
isc_mempool_setname(), add the name to isc_mempool_create() call to have
all the memory pools an unconditional name.
replace the pattern `for (result = dns_rdataset_first(x); result ==
ISC_R_SUCCES; result = dns_rdataset_next(x)` with a new
`DNS_RDATASET_FOREACH` macro throughout BIND.
the comments for some calls in the dns_message API specified
requirements which were not actually enforced in the functions.
in most cases, this has now been corrected by adding the missing
REQUIREs. in one case, the comment was incorrect and has been
revised.
previously, ISC_LIST_FOREACH and ISC_LIST_FOREACH_SAFE were
two separate macros, with the _SAFE version allowing entries
to be unlinked during the loop. ISC_LIST_FOREACH is now also
safe, and the separate _SAFE macro has been removed.
similarly, the ISC_LIST_FOREACH_REV macro is now safe, and
ISC_LIST_FOREACH_REV_SAFE has also been removed.
In a previous change, the "algorithm" value passed to
dns_tsigkey_create() was changed from a DNS name to an integer;
the name was then chosen from a table of known algorithms. A
side effect of this change was that a query using an unknown TSIG
algorithm was no longer handled correctly, and could trigger an
assertion failure. This has been corrected.
The dns_tsigkey struct now stores the signing algorithm
as dst_algorithm_t value 'alg' instead of as a dns_name,
but retains an 'algname' field, which is used only when the
algorithm is DST_ALG_UNKNOWN. This allows the name of the
unrecognized algorithm name to be returned in a BADKEY
response.
Split the YAML display of the EDNS COOKIE option into CLIENT and SERVER
parts. The STATUS of the EDNS COOKIE in the reply is now a YAML element
rather than a comment.
The offical EDNS option name for "UL" is "UPDATE-LEASE". We now
emit "UPDATE-LEASE" instead of "UL", when printing messages, but
"UL" has been retained as an alias on the command line.
Update leases consist of 1 or 2 values, LEASE and KEY-LEASE. These
components are now emitted separately so they can be easily extracted
from YAML output. Tests have been added to check YAML correctness.
When rendering text, such as domain names or the EXTRA-TEXT
field of the EDE option, backslashes and quotation marks must
be escaped to ensure that the emitted message is valid YAML.
The CHAIN and REPORT-CHANNEL EDNS options are both domain names, so they
can be combined. THE CLIENT-TAG and SERVER-TAG EDNS options are both 16
bit integers, so they can be combined.
use the ISC_LIST_FOREACH pattern in places where lists had
been iterated using a different pattern from the typical
`for` loop: for example, `while (!ISC_LIST_EMPTY(...))` or
`while ((e = ISC_LIST_HEAD(...)) != NULL)`.
ISC_LIST_FOREACH and related macros now use 'typeof(list.head)' to
declare the list elements automatically; the caller no longer needs
to do so.
ISC_LIST_FOREACH_SAFE also now implicitly declares its own 'next'
pointer, so it only needs three parameters instead of four.
In the code base it is very common to iterate over all names in a message
section and all rdatasets for each name, but various idioms are used for
iteration.
This commit standardizes them as much as possible to a single idiom,
using the macro MSG_SECTION_FOREACH, similar to the existing
ISC_LIST_FOREACH.
when searching a DNSKEY or KEY rrset for the key that matches
a particular algorithm and ID, it's a waste of time to convert
every key into a dst_key object; it's faster to compute the key
ID by checksumming the region, and then only do the full key
conversion once we know we've found the correct key.
this optimization was already in use in the validator, but it's
been refactored for code clarity, and is now also used in query.c
and message.c.
The offsets were meant to speed-up the repeated dns_name operations, but
it was experimentally proven that there's actually no real-world
benefit. Remove the offsets and labels fields from the dns_name and the
static offsets fields to save 128 bytes from the fixedname in favor of
calculating labels and offsets only when needed.
The DNS header shows if a message has multiple questions or invalid
NOTIFY sections. We can drop these messages early, right after parsing
the question. This matches RFC 9619 for multi-question messages and
Unbound's handling of NOTIFY.
To further add further robustness, we include an additional check for
unknown opcodes, and also drop those messages early.
Add early_sanity_check() function to check for these conditions:
- Messages with more than one question, as required by RFC 9619
- NOTIFY query messages containing answer sections (like Unbound)
- NOTIFY messages containing authority sections (like Unbound)
- Unknown opcodes.
Checking whether the authority section is properly signed should
be left to the validator. Checking in getsection (dns_message_parse)
was way too early and resulted in resolution failures of lookups
that should have otherwise succeeded.
Previously a hard-coded limitation of maximum two key or message
verification checks were introduced when checking the message's
SIG(0) signature. It was done in order to protect against possible
DoS attacks. The logic behind choosing the number two was that more
than one key should only be required only during key rotations, and
in that case two keys are enough. But later it became apparent that
there are other use cases too where even more keys are required, see
issue number #5050 in GitLab.
This change introduces two new configuration options for the views,
sig0key-checks-limit and sig0message-checks-limit, which define how
many keys are allowed to be checked to find a matching key, and how
many message verifications are allowed to take place once a matching
key has been found. The latter protects against expensive cryptographic
operations when there are keys with colliding tags and algorithm
numbers, with default being 2, and the former protects against a bit
less expensive key parsing operations and defaults to 16.
Instead of mixing the dns_resolver and dns_validator units directly with
the EDE code, split-out the dns_ede functionality into own separate
compilation unit and hide the implementation details behind abstraction.
Additionally, the EDE codes are directly copied into the ns_client
buffers by passing the EDE context to dns_resolver_createfetch().
This makes the dns_ede implementation simpler to use, although sligtly
more complicated on the inside.
Co-authored-by: Colin Vidal <colin@isc.org>
Co-authored-by: Ondřej Surý <ondrej@isc.org>
Extended DNS error mechanism (EDE) enables to have several EDE raised
during a DNS resolution (typically, a DNSSEC query will do multiple
fetches which each of them can have an error). Add support to up to 3
EDE errors in an DNS response. If duplicates occur (two EDEs with the
same code, the extra text is not compared), only the first one will be
part of the DNS answer.
Because the maximum number of EDE is statically fixed, `ns_client_t`
object own a static vector of `DNS_DE_MAX_ERRORS` (instead of a linked
list, for instance). The array can be fully filled (all slots point to
an allocated `dns_ednsopt_t` object) or partially filled (or
empty). In such case, the first NULL slot means there is no more EDE
objects.
Since dns_message_logpacket() only takes a single socket address as a
parameter (and it is always the sending socket's address), rename it to
dns_message_logpacketfrom() so that its name better conveys its purpose
and so that the difference in purpose between this function and
dns_message_logpacketfromto() becomes more apparent.
Since dns_message_logfmtpacket() needs to be provided with both "from"
and "to" socket addresses, rename it to dns_message_logpacketfromto() so
that its name better conveys its purpose. Clean up the code comments
for that function.
Change the function prototype for dns_message_logfmtpacket() so that it
takes two isc_sockaddr_t parameters: one for the sending side and
another one for the receiving side. This enables debug messages to be
more precise.
Also adjust the function prototype for logfmtpacket() accordingly.
Unlike dns_message_logfmtpacket(), this function must not require both
'from' and 'to' parameters to be non-NULL as it is still going to be
used by dns_message_logpacket(), which only provides a single socket
address. Adjust its log format to handle both of these cases properly.
Adjust both dns_message_logfmtpacket() call sites accordingly, without
actually providing the second socket address yet. (This causes the
revised REQUIRE() assertion in dns_message_logfmtpacket() to fail; the
issue will be addressed in a separate commit.)
Both existing callers of the dns_message_logfmtpacket() function set the
argument passed as 'style' to &dns_master_style_comment. To simplify
these call sites, drop the 'style' parameter from the prototype for
dns_message_logfmtpacket() and use a fixed value of
&dns_master_style_comment in the function's body instead.
All callers of the logfmtpacket() helper function require the argument
passed as 'address' to be non-NULL. Meanwhile, the 'newline' and
'space' local variables in logfmtpacket() are only set to values
different than their initial values if the 'address' parameter is NULL.
Replace the 'newline' and 'space' local variables in logfmtpacket() with
fixed strings to improve code readability.
