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13071 commits

Author SHA1 Message Date
Matthijs Mekking
194a72b3f1 If RPZ config'd, bail stale-answer-client-timeout
When we are recursing, RPZ processing is not allowed. But when we are
performing a lookup due to "stale-answer-client-timeout", we are still
recursing. This effectively means that RPZ processing is disabled on
such a lookup.

In this case, bail the "stale-answer-client-timeout" lookup and wait
for recursion to complete, as we we can't perform the RPZ rewrite
rules reliably.

(cherry picked from commit 3d3a6415f7)
2021-04-02 13:29:27 +02:00
Matthijs Mekking
29bcd113ea Rename "staleonly"
The dboption DNS_DBFIND_STALEONLY caused confusion because it implies
we are looking for stale data **only** and ignore any active RRsets in
the cache. Rename it to DNS_DBFIND_STALETIMEOUT as it is more clear
the option is related to a lookup due to "stale-answer-client-timeout".

Rename other usages of "staleonly", instead use "lookup due to...".
Also rename related function and variable names.

(cherry picked from commit 839df94190)
2021-04-02 13:29:17 +02:00
Matthijs Mekking
34dd6521b1 Restore the RECURSIONOK attribute after staleonly
When doing a staleonly lookup we don't want to fallback to recursion.
After all, there are obviously problems with recursion, otherwise we
wouldn't do a staleonly lookup.

When resuming from recursion however, we should restore the
RECURSIONOK flag, allowing future required lookups for this client
to recurse.

(cherry picked from commit 3f81d79ffb)
2021-04-02 13:29:09 +02:00
Matthijs Mekking
114dc7888a Remove result exception on staleonly lookup
When implementing "stale-answer-client-timeout", we decided that
we should only return positive answers prematurely to clients. A
negative response is not useful, and in that case it is better to
wait for the recursion to complete.

To do so, we check the result and if it is not ISC_R_SUCCESS, we
decide that it is not good enough. However, there are more return
codes that could lead to a positive answer (e.g. CNAME chains).

This commit removes the exception and now uses the same logic that
other stale lookups use to determine if we found a useful stale
answer (stale_found == true).

This means we can simplify two test cases in the serve-stale system
test: nodata.example is no longer treated differently than data.example.

(cherry picked from commit aaed7f9d8c)
2021-04-02 13:28:59 +02:00
Matthijs Mekking
06823aa255 Remove INSIST on NS_QUERYATTR_ANSWERED
The NS_QUERYATTR_ANSWERED attribute is to prevent sending a response
twice. Without the attribute, this may happen if a staleonly lookup
found a useful answer and sends a response to the client, and later
recursion ends and also tries to send a response.

The attribute was also used to mask adding a duplicate RRset. This is
considered harmful. When we created a response to the client with a
stale only lookup (regardless if we actually have send the response),
we should clear the rdatasets that were added during that lookup.

Mark such rdatasets with the a new attribute,
DNS_RDATASETATTR_STALE_ADDED. Set a query attribute
NS_QUERYATTR_STALEOK if we may have added rdatasets during a stale
only lookup. Before creating a response on a normal lookup, check if
we can expect rdatasets to have been added during a staleonly lookup.
If so, clear the rdatasets from the message with the attribute
DNS_RDATASETATTR_STALE_ADDED set.

(cherry picked from commit 3d5429f61f)
2021-04-02 13:28:08 +02:00
Matthijs Mekking
33d61b9651 Simplify when to detach the client
With stale-answer-client-timeout, we may send a response to the client,
but we may want to hold on to the network manager handle, because
recursion is going on in the background, or we need to refresh a
stale RRset.

Simplify the setting of 'nodetach':
* During a staleonly lookup we should not detach the nmhandle, so just
  set it prior to 'query_lookup()'.
* During a staleonly "stalefirst" lookup set the 'nodetach' to true
  if we are going to refresh the RRset.

Now there is no longer the need to clear the 'nodetach' if we go
through the "dbfind_stale", "stale_refresh_window", or "stale_only"
paths.

(cherry picked from commit 48b0dc159b)
2021-04-02 13:28:01 +02:00
Matthijs Mekking
b1496d19d5 Refactor stale lookups, ignore active RRsets
When doing a staleonly lookup, ignore active RRsets from cache. If we
don't, we may add a duplicate RRset to the message, and hit an
assertion failure in query.c because adding the duplicate RRset to the
ANSWER section failed.

This can happen on a race condition. When a client query is received,
the recursion is started. When 'stale-answer-client-timeout' triggers
around the same time the recursion completes, the following sequence
of events may happen:
1. Queue the "try stale" fetch_callback() event to the client task.
2. Add the RRsets from the authoritative response to the cache.
3. Queue the "fetch complete" fetch_callback() event to the client task.
4. Execute the "try stale" fetch_callback(), which retrieves the
   just-inserted RRset from the database.
5. In "ns_query_done()" we are still recursing, but the "staleonly"
   query attribute has already been cleared. In other words, the
   query will resume when recursion ends (it already has ended but is
   still on the task queue).
6. Execute the "fetch complete" fetch_callback(). It finds the answer
   from recursion in the cache again and tries to add the duplicate to
   the answer section.

This commit changes the logic for finding stale answers in the cache,
such that on "stale_only" lookups actually only stale RRsets are
considered. It refactors the code so that code paths for "dbfind_stale",
"stale_refresh_window", and "stale_only" are more clear.

First we call some generic code that applies in all three cases,
formatting the domain name for logging purposes, increment the
trystale stats, and check if we actually found stale data that we can
use.

The "dbfind_stale" lookup will return SERVFAIL if we didn't found a
usable answer, otherwise we will continue with the lookup
(query_gotanswer()). This is no different as before the introduction of
"stale-answer-client-timeout" and "stale-refresh-time".

The "stale_refresh_window" lookup is similar to the "dbfind_stale"
lookup: return SERVFAIL if we didn't found a usable answer, otherwise
continue with the lookup (query_gotanswer()).

Finally the "stale_only" lookup.

If the "stale_only" lookup was triggered because of an actual client
timeout (stale-answer-client-timeout > 0), and if database lookup
returned a stale usable RRset, trigger a response to the client.
Otherwise return and wait until the recursion completes (or the
resolver query times out).

If the "stale_only" lookup is a "stale-anwer-client-timeout 0" lookup,
preferring stale data over a lookup. In this case if there was no stale
data, or the data was not a positive answer, retry the lookup with the
stale options cleared, a.k.a. a normal lookup. Otherwise, continue
with the lookup (query_gotanswer()) and refresh the stale RRset. This
will trigger a response to the client, but will not detach the handle
because a fetch will be created to refresh the RRset.

(cherry picked from commit 92f7a67892)
2021-04-02 13:27:52 +02:00
Matthijs Mekking
fcf8fb4f39 Keep track of allow client detach
The stale-answer-client-timeout feature introduced a dependancy on
when a client may be detached from the handle. The dboption
DNS_DBFIND_STALEONLY was reused to track this attribute. This overloads
the meaning of this database option, and actually introduced a bug
because the option was checked in other places. In particular, in
'ns_query_done()' there is a check for 'RECURSING(qctx->client) &&
(!QUERY_STALEONLY(&qctx->client->query) || ...' and the condition is
satisfied because recursion has not completed yet and
DNS_DBFIND_STALEONLY is already cleared by that time (in
query_lookup()), because we found a useful answer and we should detach
the client from the handle after sending the response.

Add a new boolean to the client structure to keep track of client
detach from handle is allowed or not. It is only disallowed if we are
in a staleonly lookup and we didn't found a useful answer.

(cherry picked from commit fee164243f)
2021-04-02 13:27:43 +02:00
Ondřej Surý
565a6a5679 Move the dummy shims to single ifndef GSSAPI block
Previously, every function had it's own #ifdef GSSAPI #else #endif block
that defined shim function in case GSSAPI was not being used.  Now the
dummy shim functions have be split out into a single #else #endif block
at the end of the file.

This makes the gssapictx.c similar to 9.17.x code, making the backports
and reviews easier.
2021-04-01 10:42:32 +02:00
Mark Andrews
3fd30e1634 Add Heimdal compatibility support
The Heimdal Kerberos library handles the OID sets in a different manner.
Unify the handling of the OID sets between MIT and Heimdal
implementations by dynamically creating the OID sets instead of using
static predefined set.  This is how upstream recommends to handle the
OID sets.
2021-04-01 10:42:32 +02:00
Mark Andrews
a875dcc669 Remove custom ISC SPNEGO implementation
The custom ISC SPNEGO mechanism implementation is no longer needed on
the basis that all major Kerberos 5/GSSAPI (mit-krb5, heimdal and
Windows) implementations support SPNEGO mechanism since 2006.

This commit removes the custom ISC SPNEGO implementation, and removes
the option from both autoconf and win32 Configure script.  Unknown
options are being ignored, so this doesn't require any special handling.
2021-04-01 10:42:32 +02:00
Ondřej Surý
ee7283b3ee Merge branch 'bind-dyndb-ldap-v9.16.13' into 'main'
Do not require config.h to use isc/util.h

See merge request isc-projects/bind9!4840

(cherry picked from commit 19b69e9a3b)

81eb3396 Do not require config.h to use isc/util.h
2021-03-26 18:48:06 +00:00
Matthijs Mekking
1f8c5786f8 Delete CDS/CDNSKEY records when zone is unsigned
CDS/CDNSKEY DELETE records are only useful if they are signed,
otherwise the parent cannot verify these RRsets anyway. So once the DS
has been removed (and signaled to BIND), we can remove the DNSKEY and
RRSIG records, and at this point we can also remove the CDS/CDNSKEY
records.

(cherry picked from commit 6f31f62d69)
2021-03-22 13:57:10 +01:00
Matthijs Mekking
7882c7fbea Allow CDS/CDNSKEY DELETE records in unsigned zone
While not useful, having a CDS/CDNSKEY DELETE record in an unsigned
zone is not an error and "named-checkzone" should not complain.

(cherry picked from commit f211c7c2a1)
2021-03-22 13:31:02 +01:00
Matthijs Mekking
b81502f4ae Fix keymgr key init bug
The 'keymgr_key_init()' function initializes key states if they have
not been set previously. It looks at the key timing metadata and
determines using the given times whether a state should be set to
RUMOURED or OMNIPRESENT.

However, the DNSKEY and ZRRSIG states were mixed up: When looking
at the Activate timing metadata we should set the ZRRSIG state, and
when looking at the Published timing metadata we should set the
DNSKEY state.

(cherry picked from commit 27e7d5f698)
2021-03-22 11:24:55 +01:00
Patrick McLean
c5c9c9b83f Add isc_time_now_hires function to get current time with high resolution
The current isc_time_now uses CLOCK_REALTIME_COARSE which only updates
on a timer tick. This clock is generally fine for millisecond accuracy,
but on servers with 100hz clocks, this clock is nowhere near accurate
enough for microsecond accuracy.

This commit adds a new isc_time_now_hires function that uses
CLOCK_REALTIME, which gives the current time, though it is somewhat
expensive to call. When microsecond accuracy is required, it may be
required to use extra resources for higher accuracy.

(cherry picked from commit ebced74b19)
2021-03-20 11:59:21 -07:00
Witold Kręcicki
a6c4702796 Fix a startup/shutdown crash in ns_clientmgr_create 2021-03-18 15:33:28 -03:00
Witold Kręcicki
dd564da286 Shutdown interface if we can't listen on it to avoid shutdown hang 2021-03-18 15:27:28 -03:00
Ondřej Surý
121641686c Temporarily disable tlsdns_test until it gets refactored
The tlsdns API is not yet used in the 9.16 branch and the tlsdns_test
fails too often.  Temporarily disable running the test until it is
actually needed.
2021-03-18 15:42:03 +01:00
Ondřej Surý
db49ffca20 Change the isc_nm_(get|set)timeouts() to work with milliseconds
The RFC7828 specifies the keepalive interval to be 16-bit, specified in
units of 100 milliseconds and the configuration options tcp-*-timeouts
are following the suit.  The units of 100 milliseconds are very
unintuitive and while we can't change the configuration and presentation
format, we should not follow this weird unit in the API.

This commit changes the isc_nm_(get|set)timeouts() functions to work
with milliseconds and convert the values to milliseconds before passing
them to the function, not just internally.
2021-03-18 15:16:13 +01:00
Ondřej Surý
5d0647e067 Merge the common parts between udp, tcpdns and tlsdns protocol
The udp, tcpdns and tlsdns contained lot of cut&paste code or code that
was very similar making the stack harder to maintain as any change to
one would have to be copied to the the other protocols.

In this commit, we merge the common parts into the common functions
under isc__nm_<foo> namespace and just keep the little differences based
on the socket type.
2021-03-18 15:16:13 +01:00
Ondřej Surý
a017ba2615 Fix TCPDNS and TLSDNS timers
After the TCPDNS refactoring the initial and idle timers were broken and
only the tcp-initial-timeout was always applied on the whole TCP
connection.

This broke any TCP connection that took longer than tcp-initial-timeout,
most often this would affect large zone AXFRs.

This commit changes the timeout logic in this way:

  * On TCP connection accept the tcp-initial-timeout is applied
    and the timer is started
  * When we are processing and/or sending any DNS message the timer is
    stopped
  * When we stop processing all DNS messages, the tcp-idle-timeout
    is applied and the timer is started again
2021-03-18 15:16:13 +01:00
Mark Andrews
3f9d7227b3 Stop using deprecated calls in lib/isc/tls.c
from Rosen Penev @neheb

(cherry picked from commit a9f883cbc2)
2021-03-18 10:15:44 +11:00
Matthijs Mekking
1a29d7ae7d Fully sign a thawed zone
When thawing a zone, we don't know what changes have been made. If we
do DNSSEC maintenance on this zone, schedule a full sign.

(cherry picked from commit b90846f222)
2021-03-17 11:12:39 +01:00
Matthijs Mekking
3ae16d0480 Fix "unable to thaw dynamic kasp zone"
Dynamic zones with dnssec-policy could not be thawed because KASP
zones were considered always dynamic. But a dynamic KASP zone should
also check whether updates are disabled.

(cherry picked from commit b518ed9f46)
2021-03-17 11:12:29 +01:00
Matthijs Mekking
96953fc293
Fix servestale fetchlimits crash
When we query the resolver for a domain name that is in the same zone
for which is already one or more fetches outstanding, we could
potentially hit the fetch limits. If so, recursion fails immediately
for the incoming query and if serve-stale is enabled, we may try to
return a stale answer.

If the resolver is also is authoritative for the parent zone (for
example the root zone), first a delegation is found, but we first
check the cache for a better response.

Nothing is found in the cache, so we try to recurse to find the
answer to the query.

Because of fetch-limits 'dns_resolver_createfetch()' returns an error,
which 'ns_query_recurse()' propagates to the caller,
'query_delegation_recurse()'.

Because serve-stale is enabled, 'query_usestale()' is called,
setting 'qctx->db' to the cache db, but leaving 'qctx->version'
untouched. Now 'query_lookup()' is called to search for stale data
in the cache database with a non-NULL 'qctx->version'
(which is set to a zone db version), and thus we hit an assertion
in rbtdb.

This crash was introduced in 'v9_16' by commit
2afaff75ed.

(cherry picked from commit 87591de6f7)
2021-03-11 13:47:20 +01:00
Evan Hunt
401642cbb4 fix automatic journal upgrade on windows
- use a value less than 2^32 for DNS_ZONEFLG_FIXJOURNAL; a larger value
  could cause problems in some build environments. the zone flag
  DNS_ZONEFLG_DIFFONRELOAD, which was no longer in use, has now been
  deleted and its value reused for _FIXJOURNAL.

(cherry picked from commit 990dd9dbff)
2021-03-08 09:43:00 +01:00
Evan Hunt
2aed5c5954 add start and end serial numbers to 'named-printjournal -x'
add the starting and ending serial number from the journal
header to the output of dns_journal_print().

(cherry picked from commit 46c11726d4)
2021-03-08 09:43:00 +01:00
Mark Andrews
898e9989f9 Silence CID 329159: Logically dead code in lib/dns/journal.c
*** CID 329159:    (DEADCODE)
    /lib/dns/journal.c: 1719 in dns_journal_print()
    1713     		}
    1714     		CHECK(dns_difftuple_create(
    1715     			diff.mctx, n_soa == 1 ? DNS_DIFFOP_DEL : DNS_DIFFOP_ADD,
    1716     			name, ttl, rdata, &tuple));
    1717     		dns_diff_append(&diff, &tuple);
    1718
    >>>     CID 329159:    (DEADCODE)
    >>>     Execution cannot reach the expression "printxhdr" inside this statement: "if (++n_put != 0U || printx...".
    1719     		if (++n_put != 0 || printxhdr) {
    1720     			result = dns_diff_print(&diff, file);
    1721     			dns_diff_clear(&diff);
    1722     			n_put = 0;
    1723     			if (result != ISC_R_SUCCESS) {
    1724     				break;
    /lib/dns/journal.c: 1734 in dns_journal_print()
    1728     	if (result == ISC_R_NOMORE) {
    1729     		result = ISC_R_SUCCESS;
    1730     	}
    1731     	CHECK(result);
    1732
    1733     	if (!printxhdr && n_put != 0) {
    >>>     CID 329159:    (DEADCODE)
    >>>     Execution cannot reach this statement: "result = dns_diff_print(&di...".
    1734     		result = dns_diff_print(&diff, file);
    1735     		dns_diff_clear(&diff);
    1736     	}
    1737     	goto cleanup;
    1738
    1739     failure:

(cherry picked from commit 848e336db4)
2021-03-08 16:44:43 +11:00
Mark Andrews
fb7e38cca2 Silence CID 329157: Dereference before null check in lib/dns/journal.c
*** CID 329157:  Null pointer dereferences  (REVERSE_INULL)
    /lib/dns/journal.c: 754 in journal_open()
    748     			    j->header.index_size * sizeof(journal_rawpos_t));
    749     	}
    750     	if (j->index != NULL) {
    751     		isc_mem_put(j->mctx, j->index,
    752     			    j->header.index_size * sizeof(journal_pos_t));
    753     	}
       CID 329157:  Null pointer dereferences  (REVERSE_INULL)
       Null-checking "j->filename" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.
    754     	if (j->filename != NULL) {
    755     		isc_mem_free(j->mctx, j->filename);
    756     	}
    757     	if (j->fp != NULL) {
    758     		(void)isc_stdio_close(j->fp);
    759     	}

(cherry picked from commit 4054405909)
2021-03-08 16:12:01 +11:00
Ondřej Surý
1c2e018962 Assigning uint64_t from buffer might be misaligned in netmgr tests
Resolve possible 8-byte unaligned access when assigning the magic
value from the received buffer.

(cherry picked from commit a55bdb28f9)
2021-03-04 15:29:44 +01:00
Mark Andrews
985566fea5
Fixed librpz_dnsrpzd_path being a duplicate symbol
librpz_dnsrpzd_path should have been declared extern in dns/librpz.h

(cherry picked from commit 8f016dd57a)
2021-03-04 11:28:49 +01:00
Evan Hunt
9f1f5abe0e print journal index data and test for consistency
'named-journalprint -x' now prints the journal's index table and
the offset of each transaction in the journal, so that index consistency
can be confirmed.

(cherry picked from commit a4972324a6)
2021-03-03 19:19:50 -08:00
Mark Andrews
5aea511e1b extend named-journalprint to be able to force the journal version
named-journalprint can now upgrade or downgrade a journal file
in place; the '-u' option upgrades and the '-d' option downgrades.

(cherry picked from commit fb2d0e2897)
2021-03-03 19:19:50 -08:00
Evan Hunt
47a274e9f1 allow dns_journal_rollforward() to read old journal files
when the 'max-ixfr-ratio' option was added, journal transaction
headers were revised to include a count of RR's in each transaction.
this made it impossible to read old journal files after an upgrade.

this branch restores the ability to read version 1 transaction
headers. when rolling forward, printing journal contents, if
the wrong transaction header format is found, we can switch.

when dns_journal_rollforward() detects a version 1 transaction
header, it returns DNS_R_RECOVERABLE.  this triggers zone_postload()
to force a rewrite of the journal file in the new format, and
also to schedule a dump of the zone database with minimal delay.
journal repair is done by dns_journal_compact(), which rewrites
the entire journal, ignoring 'max-journal-size'. journal size is
corrected later.

newly created journal files now have "BIND LOG V9.2" in their headers
instead of "BIND LOG V9". files with the new version string cannot be
read using the old transaction header format. note that this means
newly created journal files will be rejected by older versions of named.

named-journalprint now takes a "-x" option, causing it to print
transaction header information before each delta, including its
format version.

(cherry picked from commit ee19966326)
2021-03-03 19:19:50 -08:00
Mark Andrews
7a703244ed Address theoretical buffer overrun in recent change
The strlcat() call was wrong.

    *** CID 316608:  Memory - corruptions  (OVERRUN)
    /lib/dns/resolver.c: 5017 in fctx_create()
    5011     	 * Make fctx->info point to a copy of a formatted string
    5012     	 * "name/type".
    5013     	 */
    5014     	dns_name_format(name, buf, sizeof(buf));
    5015     	dns_rdatatype_format(type, typebuf, sizeof(typebuf));
    5016     	p = strlcat(buf, "/", sizeof(buf));
    >>>     CID 316608:  Memory - corruptions  (OVERRUN)
    >>>     Calling "strlcat" with "buf + p" and "1036UL" is suspicious because "buf" points into a buffer of 1036 bytes and the function call may access "(char *)(buf + p) + 1035UL". [Note: The source code implementation of the function has been overridden by a builtin model.]
    5017     	strlcat(buf + p, typebuf, sizeof(buf));
    5018     	fctx->info = isc_mem_strdup(mctx, buf);
    5019
    5020     	FCTXTRACE("create");
    5021     	dns_name_init(&fctx->name, NULL);
    5022     	dns_name_dup(name, mctx, &fctx->name);

(cherry picked from commit 59bf6e71e2)
2021-03-03 10:55:38 +01:00
Ondřej Surý
59d92c8af8 Call isc__initialize()/isc__shutdown() from win32 DllMain
Call the libisc isc__initialize() constructor and isc__shutdown()
destructor from DllMain instead of having duplicate code between
those and DllMain() code.

(cherry picked from commit a50f5d0cf5)
2021-03-02 08:50:29 +01:00
Ondřej Surý
86298fd112 Make linker include library ctor/dtor in statically linked libisc
Under normal situation, the linker throws out all symbols from
compilation unit when no symbols are used in the final binary, which is
the case for lib/isc/lib.c.  This commit adds empty function to lib.c
that's being called from different CU (mem.c in this case) and that
makes the linker to include all the symbols including the normally
unreferenced isc__initialize() and isc__shutdown() in the final binary.
2021-02-26 21:19:33 +01:00
Ondřej Surý
f92b77ff0d Change the isc_thread_self() return type to uintptr_t
The pthread_self(), thrd_current() or GetCurrentThreadId() could
actually be a pointer, so we should rather convert the value into
uintptr_t instead of unsigned long.

(cherry picked from commit a0181056a8)
2021-02-26 21:14:17 +01:00
Ondřej Surý
0e90858d99 Use globally assigned thread_id in the isc_hp API
Convert the isc_hp API to use the globally available isc_tid_v instead
of locally defined tid_v.  This should solve most of the problems on
machines with many number of cores / CPUs.

(cherry picked from commit bea333f7c9)
2021-02-26 21:14:17 +01:00
Ondřej Surý
45c55b1e7e Add isc_trampoline API to have simple accounting around threads
The current isc_hp API uses internal tid_v variable that gets
incremented for each new thread using hazard pointers.  This tid_v
variable is then used as a index to global shared table with hazard
pointers state.  Since the tid_v is only incremented and never
decremented the table could overflow very quickly if we create set of
threads for short period of time, they finish the work and cease to
exist.  Then we create identical set of threads and so on and so on.
This is not a problem for a normal `named` operation as the set of
threads is stable, but the problematic place are the unit tests where we
test network manager or other APIs (task, timer) that create threads.

This commits adds a thin wrapper around any function called from
isc_thread_create() that adds unique-but-reusable small digit thread id
that can be used as index to f.e. hazard pointer tables.  The trampoline
wrapper ensures that the thread ids will be reused, so the highest
thread_id number doesn't grow indefinitely when threads are created and
destroyed and then created again.  This fixes the hazard pointer table
overflow on machines with many cores. [GL #2396]

(cherry picked from commit cbbecfcc82)
2021-02-26 21:14:17 +01:00
Ondřej Surý
0bd834856e Enforce disabling internal memory allocator for AddressSanitizer
Disable the internal memory allocator when AddressSanitizer is in use.
The basic blocks in the internal memory allocator prevents
AddressSanitizer from properly tracking the allocations and
deallocations, so we need to ensure it has been disabled for any build
that has AddressSanitizer enabled.
2021-02-26 10:13:56 -08:00
Ondřej Surý
1cd14c4dec Add mempool get/put tracking with AddressSanitizer
When AddressSanitizer is in use, disable the internal mempool
implementation and redirect the isc_mempool_get to isc_mem_get
(and similarly for isc_mempool_put). This is the method recommended
by the AddressSanitizer authors for tracking allocations and
deallocations instead of custom poison/unpoison code (see
https://github.com/google/sanitizers/wiki/AddressSanitizerManualPoisoning).
2021-02-26 10:13:17 -08:00
Ondřej Surý
2011efa99d Disable safe-guard assertion in DLL_THREAD_ATTACH/DLL_THREAD_DETACH
The BIND 9 libraries on Windows define DllMain() optional entry point
into a dynamic-link library (DLL).  When the system starts or terminates
a process or thread, it calls the entry-point function for each loaded
DLL using the first thread of the process.

When the DLL is being loaded into the virtual address space of the
current process as a result of the process starting up, we make a call
to DisableThreadLibraryCalls() which should disable the
DLL_THREAD_ATTACH and DLL_THREAD_DETACH notifications for the specified
dynamic-link library (DLL).

This seems not be the case because we never check the return value of
the DisableThreadLibraryCalls() call, and it could in fact fail.  The
DisableThreadLibraryCalls() function fails if the DLL specified by
hModule has active static thread local storage, or if hModule is an
invalid module handle.

In this commit, we remove the safe-guard assertion put in place for the
DLL_THREAD_ATTACH and DLL_THREAD_DETACH events and we just ignore them.
BIND 9 doesn't create/destroy enough threads for it actually to make any
difference, and in fact we do use static thread local storage in the
code.
2021-02-26 17:18:06 +01:00
Ondřej Surý
2f0f531ee8 Use library constructor/destructor to initialize OpenSSL
Instead of calling isc_tls_initialize()/isc_tls_destroy() explicitly use
gcc/clang attributes on POSIX and DLLMain on Windows to initialize and
shutdown OpenSSL library.

This resolves the issue when isc_nm_create() / isc_nm_destroy() was
called multiple times and it would call OpenSSL library destructors from
isc_nm_destroy().

At the same time, since we now have introduced the ctor/dtor for libisc,
this commit moves the isc_mem API initialization (the list of the
contexts) and changes the isc_mem_checkdestroyed() to schedule the
checking of memory context on library unload instead of executing the
code immediately.
2021-02-26 17:18:06 +01:00
Ondřej Surý
59d51cdeb6 Disable calling DllMain() on thread creation/destruction
Disables the DLL_THREAD_ATTACH and DLL_THREAD_DETACH notifications for
the specified dynamic-link library (DLL).  This can reduce the size of
the working set for some applications.
2021-02-26 17:07:15 +01:00
Ondřej Surý
6883d4bd08 Fix the invalid condition variable
Although harmless, the memmove() in tlsdns and tcpdns was guarded by a
current message length variable that was always bigger than 0 instead of
correct current buffer length remainder variable.
2021-02-26 17:07:09 +01:00
Ondřej Surý
6da91bf16c Move most of the OpenSSL initialization to isc_tls
Since we now require both libcrypto and libssl to be initialized for
netmgr, we move all the OpenSSL initialization code except the engine
initialization to isc_tls API.

The isc_tls_initialize() and isc_tls_destroy() has been made idempotent,
so they could be called multiple time.  However when isc_tls_destroy()
has been called, the isc_tls_initialize() could not be called again.
2021-02-26 17:07:01 +01:00
Ondřej Surý
effe3ee595 Refactor TLSDNS module to work with libuv/ssl directly
* Following the example set in 634bdfb16d, the tlsdns netmgr
  module now uses libuv and SSL primitives directly, rather than
  opening a TLS socket which opens a TCP socket, as the previous
  model was difficult to debug.  Closes #2335.

* Remove the netmgr tls layer (we will have to re-add it for DoH)

* Add isc_tls API to wrap the OpenSSL SSL_CTX object into libisc
  library; move the OpenSSL initialization/deinitialization from dstapi
  needed for OpenSSL 1.0.x to the isc_tls_{initialize,destroy}()

* Add couple of new shims needed for OpenSSL 1.0.x

* When LibreSSL is used, require at least version 2.7.0 that
  has the best OpenSSL 1.1.x compatibility and auto init/deinit

* Enforce OpenSSL 1.1.x usage on Windows

(cherry picked from commit e493e04c0f)
2021-02-26 16:14:50 +01:00
Matthijs Mekking
acc95d4e1d Don't servfail on staleonly lookups
When a staleonly lookup doesn't find a satisfying answer, it should
not try to respond to the client.

This is not true when the initial lookup is staleonly (that is when
'stale-answer-client-timeout' is set to 0), because no resolver fetch
has been created at this point. In this case continue with the lookup
normally.

(cherry picked from commit f8b7b597e9)
2021-02-25 12:07:34 +01:00
Matthijs Mekking
84deb57bc3 Don't allow recursion on staleonly lookups
Fix a crash that can happen in the following scenario:

A client request is received. There is no data for it in the cache,
(not even stale data). A resolver fetch is created as part of
recursion.

Some time later, the fetch still hasn't completed, and
stale-answer-client-timeout is triggered. A staleonly lookup is
started. It will also find no data in the cache.

So 'query_lookup()' will call 'query_gotanswer()' with ISC_R_NOTFOUND,
so this will call 'query_notfound()' and this will start recursion.

We will eventually end up in 'ns_query_recurse()' and that requires
the client query fetch to be NULL:

    REQUIRE(client->query.fetch == NULL);

If the previously started fetch is still running this assertion
fails.

The crash is easily prevented by not requiring recursion for
staleonly lookups.

Also remove a redundant setting of the staleonly flag at the end of
'query_lookup_staleonly()' before destroying the query context.

Add a system test to catch this case.

(cherry picked from commit 9e061faaae)
2021-02-25 12:07:27 +01:00
Matthijs Mekking
d51df34995 Fix dnssec-policy NSEC3 on dynamic zones
When applying dnssec-policy on a dynamic zone (e.g. that allows Dynamic
Updates), the NSEC3 parameters were put on the queue, but they were
not being processed (until a reload of the zone or reconfiguration).

Process the NSEC3PARAM queue on zone postload when handling a
dynamic zone.

(cherry picked from commit 4b176c850b)
2021-02-25 10:56:00 +01:00
Michal Nowak
b36690e750
Initialize checknames field in dns_view_create()
The 'checknames' field wasn't initialized in dns_view_create(), but it
should otherwise AddressSanitizer identifies the following runtime error
in query_test.c.

    runtime error: load of value 190, which is not a valid value for type '_Bool'

(cherry picked from commit 0c6fa16477)
2021-02-23 16:45:36 +01:00
Matthijs Mekking
8e4d0d51be Purge keys implementation
On each keymgr run, we now also check if key files can be removed.
The 'purge-keys' interval determines how long keys should be retained
after they have become completely hidden.

Key files should not be removed if it has a state that is set to
something else then HIDDEN, if purge-keys is 0 (disabled), if
the key goal is set to OMNIPRESENT, or if the key is unused (a key is
unused if no timing metadata set, and no states are set or if set,
they are set to HIDDEN).

If the last changed timing metadata plus the purge-keys interval is
in the past, the key files may be removed.

Add a dst_key_t variable 'purge' to signal that the key file should
not be written to file again.

(cherry picked from commit 8c526cb67f)
2021-02-23 09:19:03 +01:00
Matthijs Mekking
45dcabf411 Add purge-keys config option
Add a new option 'purge-keys' to 'dnssec-policy' that will purge key
files for deleted keys. The option determines how long key files
should be retained prior to removing the corresponding files from
disk.

If set to 0, the option is disabled and 'named' will not remove key
files from disk.

(cherry picked from commit 313de3a7e2)
2021-02-23 09:18:55 +01:00
Mark Andrews
4e192d2fe7 Address theoretical resource leak in dns_dt_open()
dns_dt_open() is not currently called with mode dns_dtmode_unix.

    *** CID 281489:  Resource leaks  (RESOURCE_LEAK)
    /lib/dns/dnstap.c: 983 in dns_dt_open()
    977
    978     		if (!dnstap_file(handle->reader)) {
    979     			CHECK(DNS_R_BADDNSTAP);
    980     		}
    981     		break;
    982     	case dns_dtmode_unix:
       CID 281489:  Resource leaks  (RESOURCE_LEAK)
       Variable "handle" going out of scope leaks the storage it points to.
    983     		return (ISC_R_NOTIMPLEMENTED);
    984     	default:
    985     		INSIST(0);
    986     		ISC_UNREACHABLE();
    987     	}
    988

(cherry picked from commit 003dd8cc70)
2021-02-23 09:41:15 +11:00
Mark Andrews
d68b85e555 Correctly detect when get_direction failed
(cherry picked from commit 009358d77d)
2021-02-19 11:39:12 +11:00
Mark Andrews
0cea486327 Test a LOC record with an invalid direction field
(cherry picked from commit 07902d9f9d)
2021-02-19 11:39:12 +11:00
Ondřej Surý
b04cb88462 Fix off-by-one bug in ISC SPNEGO implementation
The ISC SPNEGO implementation is based on mod_auth_kerb code.  When
CVE-2006-5989 was disclosed, the relevant fix was not applied to the
BIND 9 codebase, making the latter vulnerable to the aforementioned flaw
when "tkey-gssapi-keytab" or "tkey-gssapi-credential" is set in
named.conf.

The original description of CVE-2006-5989 was:

    Off-by-one error in the der_get_oid function in mod_auth_kerb 5.0
    allows remote attackers to cause a denial of service (crash) via a
    crafted Kerberos message that triggers a heap-based buffer overflow
    in the component array.

Later research revealed that this flaw also theoretically enables remote
code execution, though achieving the latter in real-world conditions is
currently deemed very difficult.

This vulnerability was responsibly reported as ZDI-CAN-12302 ("ISC BIND
TKEY Query Heap-based Buffer Overflow Remote Code Execution
Vulnerability") by Trend Micro Zero Day Initiative.
2021-02-17 22:36:08 +01:00
Ondřej Surý
d7b3a6a016 Rollback setting IP_DONTFRAG option on the UDP sockets
In DNS Flag Day 2020, the development branch started setting the
IP_DONTFRAG option on the UDP sockets.  It turned out, that this
code was incomplete leading to dropping the outgoing UDP packets.
Henceforth this commit rolls back this setting until we have a
proper fix that would send back empty response with TC flag set.

(cherry picked from commit 66eefac78c)
2021-02-17 14:41:56 +01:00
Michal Nowak
f483b102dd
Drop USE_OPENSSL constraint from dh_test
The USE_OPENSSL constraint in dh_test does not seems to be necessary
anymore, the test runs with PKCS#11 as well.

(cherry picked from commit c341e7f740)
2021-02-17 12:46:25 +01:00
Michal Nowak
ed38e32b69
Ensure dnstap_test returns SKIPPED_TEST_EXIT_CODE
Make sure lib/dns/tests/dnstap_test returns an exit code that indicates
a skipped test when dnstap is not enabled.

(cherry picked from commit c286341703)
2021-02-17 12:15:18 +01:00
Michal Nowak
04aff208fb
Use BIND 9.17 preprocessor macro to skip unit test
BIND 9.17 changed exit code of skipped test to meet Automake
expectations in fa505bfb0e. BIND 9.16 was
not rewritten to Automake, but for consistency reasons, the same
SKIPPED_TEST_EXIT_CODE preprocessor macro is used (though the actual
exit code differs from the one in BIND 9.17).

(cherry picked from commit fa505bfb0e)
2021-02-17 12:09:25 +01:00
Mark Andrews
d51b78c85b Stop including <gssapi.h> from <dst/gssapi.h> header
The only reason for including the gssapi.h from the dst/gssapi.h header
was to get the typedefs of gss_cred_id_t and gss_ctx_id_t.  Instead of
using those types directly this commit introduces dns_gss_cred_id_t and
dns_gss_ctx_id_t types that are being used in the public API and
privately retyped to their counterparts when we actually call the gss
api.

This also conceals the gssapi headers, so users of the libdns library
doesn't have to add GSSAPI_CFLAGS to the Makefile when including libdns
dst API.
2021-02-16 12:08:21 +11:00
Ondřej Surý
4bbe3e75de Stop including dnstap headers from <dns/dnstap.h>
The <fstrm.h> and <protobuf-c/protobuf-c.h> headers are only directly
included where used and we stopped exposing those headers from libdns
headers.
2021-02-16 12:08:21 +11:00
Mark Andrews
bf5aac225b Stop including <lmdb.h> from <dns/lmdb.h>
The lmdb.h header doesn't have to be included from the dns/lmdb.h
header as it can be separately included where used.  This stops
exposing the inclusion of lmdb.h from the libdns headers.
2021-02-16 12:08:21 +11:00
Mark Andrews
b8fc8742e5 Re-order include directories
${FSTRM_CFLAGS} ${PROTOBUF_C_CFLAGS} ${OPENSSL_CFLAGS} ${LMDB_CFLAGS}
need to appear after all directories in the build tree.
2021-02-16 12:08:21 +11:00
Diego Fronza
d89a8bf696 Fix dangling references to outdated views after reconfig
This commit fix a leak which was happening every time an inline-signed
zone was added to the configuration, followed by a rndc reconfig.

During the reconfig process, the secure version of every inline-signed
zone was "moved" to a new view upon a reconfig and it "took the raw
version along", but only once the secure version was freed (at shutdown)
was prev_view for the raw version detached from, causing the old view to
be released as well.

This caused dangling references to be kept for the previous view, thus
keeping all resources used by that view in memory.
2021-02-15 11:52:50 -03:00
Mark Andrews
6e30caed57 Silence Insecure data handling (TAINTED_SCALAR)
Coverity assumes that the memory holding any value read using byte
swapping is tainted.  As we store the NSEC3PARAM records in wire
form and iterations is byte swapped the memory holding the record
is marked as tainted.  nsec3->salt_length is marked as tainted
transitively. To remove the taint the value need to be range checked.
For a correctly formatted record region.length should match
nsec3->salt_length and provides a convenient value to check the field
against.

    *** CID 316507:  Insecure data handling  (TAINTED_SCALAR)
    /lib/dns/rdata/generic/nsec3param_51.c: 241 in tostruct_nsec3param()
    235     	region.length = rdata->length;
    236     	nsec3param->hash = uint8_consume_fromregion(&region);
    237     	nsec3param->flags = uint8_consume_fromregion(&region);
    238     	nsec3param->iterations = uint16_consume_fromregion(&region);
    239
    240     	nsec3param->salt_length = uint8_consume_fromregion(&region);
    >>>     CID 316507:  Insecure data handling  (TAINTED_SCALAR)
    >>>     Passing tainted expression "nsec3param->salt_length" to "mem_maybedup", which uses it as an offset.
    241     	nsec3param->salt = mem_maybedup(mctx, region.base,
    242     					nsec3param->salt_length);
    243     	if (nsec3param->salt == NULL) {
    244     		return (ISC_R_NOMEMORY);
    245     	}
    246     	isc_region_consume(&region, nsec3param->salt_length);

(cherry picked from commit c40133d840)
2021-02-12 10:43:19 +11:00
Mark Andrews
8302e9fb69 Silence Untrusted value as argument (TAINTED_SCALAR)
Coverity assumes that the memory holding any value read using byte
swapping is tainted.  As we store the NSEC3 records in wire form
and iterations is byte swapped the memory holding the record is
marked as tainted.  nsec3->salt_length and nsec3->next_length are
marked as tainted transitively. To remove the taint the values need
to be range checked.  Valid values for these should never exceed
region.length so that is becomes a reasonable value to check against.

    *** CID 316509:    (TAINTED_SCALAR)
    /lib/dns/rdata/generic/nsec3_50.c: 312 in tostruct_nsec3()
    306     	if (nsec3->salt == NULL) {
    307     		return (ISC_R_NOMEMORY);
    308     	}
    309     	isc_region_consume(&region, nsec3->salt_length);
    310
    311     	nsec3->next_length = uint8_consume_fromregion(&region);
    >>>     CID 316509:    (TAINTED_SCALAR)
    >>>     Passing tainted expression "nsec3->next_length" to "mem_maybedup", which uses it as an offset.
    312     	nsec3->next = mem_maybedup(mctx, region.base, nsec3->next_length);
    313     	if (nsec3->next == NULL) {
    314     		goto cleanup;
    315     	}
    316     	isc_region_consume(&region, nsec3->next_length);
    317
    /lib/dns/rdata/generic/nsec3_50.c: 305 in tostruct_nsec3()
    299     	region.length = rdata->length;
    300     	nsec3->hash = uint8_consume_fromregion(&region);
    301     	nsec3->flags = uint8_consume_fromregion(&region);
    302     	nsec3->iterations = uint16_consume_fromregion(&region);
    303
    304     	nsec3->salt_length = uint8_consume_fromregion(&region);
    >>>     CID 316509:    (TAINTED_SCALAR)
    >>>     Passing tainted expression "nsec3->salt_length" to "mem_maybedup", which uses it as an offset.
    305     	nsec3->salt = mem_maybedup(mctx, region.base, nsec3->salt_length);
    306     	if (nsec3->salt == NULL) {
    307     		return (ISC_R_NOMEMORY);
    308     	}
    309     	isc_region_consume(&region, nsec3->salt_length);
    310

(cherry picked from commit fd8d1337a5)
2021-02-12 10:43:19 +11:00
Michal Nowak
001413ed50
Drop AddressSanitizer constraint from libns unit tests
The AddressSanitizer constraint in some libns unit tests does not seem
to be necessary anymore, these tests run fine under AddressSanitizer.

(cherry picked from commit 613be8706e)
2021-02-10 11:03:27 +01:00
Matthijs Mekking
2afaff75ed Use stale on error also when unable to recurse
The 'query_usestale()' function was only called when in
'query_gotanswer()' and an unexpected error occurred. This may have
been "quota reached", and thus we were in some cases returning
stale data on fetch-limits (and if serve-stale enabled of course).

But we can also hit fetch-limits when recursing because we are
following a referral (in 'query_notfound()' and
'query_delegation_recurse()'). Here we should also check for using
stale data in case an error occurred.

Specifically don't check for using stale data when refetching a
zero TTL RRset from cache.

Move the setting of DNS_DBFIND_STALESTART into the 'query_usestale()'
function to avoid code duplication.

(cherry picked from commit 8bcd7fe69e)
2021-02-08 16:10:03 +01:00
Matthijs Mekking
dbf5428629 Only start stale refresh window when resuming
If we did not attempt a fetch due to fetch-limits, we should not start
the stale-refresh-time window.

Introduce a new flag DNS_DBFIND_STALESTART to differentiate between
a resolver failure and unexpected error. If we are resuming, this
indicates a resolver failure, then start the stale-refresh-time window,
otherwise don't start the stale-refresh-time window, but still fall
back to using stale data.

(This commit also wraps some docstrings to 80 characters width)

(cherry picked from commit aabdedeae3)
2021-02-08 16:07:43 +01:00
Matthijs Mekking
809ec0a224 Use stale data also if we are not resuming
Before this change, BIND will only fallback to using stale data if
there was an actual attempt to resolve the query. Then on a timeout,
the stale data from cache becomes eligible.

This commit changes this so that on any unexpected error stale data
becomes eligble (you would still have to have 'stale-answer-enable'
enabled of course).

If there is no stale data, this may return in an error again, so don't
loop on stale data lookup attempts. If the DNS_DBFIND_STALEOK flag is
set, this means we already tried to lookup stale data, so if that is
the case, don't use stale again.

(cherry picked from commit c6fd02aed5)
2021-02-08 16:07:43 +01:00
Mark Andrews
8092b7eec6 Remove redundant 'version == NULL' check
*** CID 318094:  Null pointer dereferences  (REVERSE_INULL)
    /lib/dns/rbtdb.c: 1389 in newversion()
    1383     	version->xfrsize = rbtdb->current_version->xfrsize;
    1384     	RWUNLOCK(&rbtdb->current_version->rwlock, isc_rwlocktype_read);
    1385     	rbtdb->next_serial++;
    1386     	rbtdb->future_version = version;
    1387     	RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write);
    1388
       CID 318094:  Null pointer dereferences  (REVERSE_INULL)
       Null-checking "version" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.
    1389     	if (version == NULL) {
    1390     		return (result);
    1391     	}
    1392
    1393     	*versionp = version;
    1394

(cherry picked from commit 456d53d1fb)
2021-02-08 16:17:52 +11:00
Mark Andrews
a900d79ea8 Cleanup redundant isc_rwlock_init() result checks
(cherry picked from commit 3b11bacbb7)
2021-02-08 15:13:49 +11:00
Mark Andrews
c2a5b88275 Attempt to silence untrusted loop bound
Assign hit_len + key_len to len and test the result
rather than recomputing and letting the compiler simplify.

    213        isc_region_consume(&region, 2); /* hit length + algorithm */
        9. tainted_return_value: Function uint16_fromregion returns tainted data. [show details]
        10. tainted_data_transitive: Call to function uint16_fromregion with tainted argument *region.base returns tainted data.
        11. tainted_return_value: Function uint16_fromregion returns tainted data.
        12. tainted_data_transitive: Call to function uint16_fromregion with tainted argument *region.base returns tainted data.
        13. var_assign: Assigning: key_len = uint16_fromregion(&region), which taints key_len.
    214        key_len = uint16_fromregion(&region);
        14. lower_bounds: Casting narrower unsigned key_len to wider signed type int effectively tests its lower bound.
        15. Condition key_len == 0, taking false branch.
    215        if (key_len == 0) {
    216                RETERR(DNS_R_FORMERR);
    217        }
        16. Condition !!(_r->length >= _l), taking true branch.
        17. Condition !!(_r->length >= _l), taking true branch.
    218        isc_region_consume(&region, 2);
        18. lower_bounds: Casting narrower unsigned key_len to wider signed type int effectively tests its lower bound.
        19. Condition region.length < (unsigned int)(hit_len + key_len), taking false branch.
    219        if (region.length < (unsigned)(hit_len + key_len)) {
    220                RETERR(DNS_R_FORMERR);
    221        }
    222
        20. lower_bounds: Casting narrower unsigned key_len to wider signed type int effectively tests its lower bound.
        21. Condition _r != 0, taking false branch.
    223        RETERR(mem_tobuffer(target, rr.base, 4 + hit_len + key_len));
        22. lower_bounds: Casting narrower unsigned key_len to wider signed type int effectively tests its lower bound.
        23. var_assign_var: Compound assignment involving tainted variable 4 + hit_len + key_len to variable source->current taints source->current.
    224        isc_buffer_forward(source, 4 + hit_len + key_len);
    225
    226        dns_decompress_setmethods(dctx, DNS_COMPRESS_NONE);

    CID 281461 (#1 of 1): Untrusted loop bound (TAINTED_SCALAR)
        24. tainted_data: Using tainted variable source->active - source->current as a loop boundary.
    Ensure that tainted values are properly sanitized, by checking that their values are within a permissible range.
    227        while (isc_buffer_activelength(source) > 0) {
    228                dns_name_init(&name, NULL);
    229                RETERR(dns_name_fromwire(&name, source, dctx, options, target));
    230        }

(cherry picked from commit 2f946c831a)
2021-02-08 14:05:11 +11:00
Mark Andrews
6da9f238d4 Allow A records below '_spf' labels as recommend by RFC7208
(cherry picked from commit 63c16c8506)
2021-02-03 16:26:25 +01:00
Matthijs Mekking
ce2a37a990 Use NUM_KEYSTATES constant where appropriate
We use the number 4 a lot when working on key states. Better to use
the NUM_KEYSTATES constant instead.

(cherry picked from commit 98ace6d97d)
2021-02-03 15:48:20 +01:00
Matthijs Mekking
a8fba11da9 Cleanup keymgr.c
Three small cleanups:

1. Remove an unused keystr/dst_key_format.
2. Initialize a dst_key_state_t state with NA.
3. Update false comment about local policy (local policy only adds
   barrier on transitions to the RUMOURED state, not the UNRETENTIVE
   state).

(cherry picked from commit 189d9a2d21)
2021-02-03 15:47:40 +01:00
Matthijs Mekking
ceac392e19 Fix DS/DNSKEY hidden or chained functions
There was a bug in function 'keymgr_ds_hidden_or_chained()'.

The funcion 'keymgr_ds_hidden_or_chained()' implements (3e) of rule2
as defined in the "Flexible and Robust Key Rollover" paper. The rules
says: All DS records need to be in the HIDDEN state, or if it is not
there must be a key with its DNSKEY and KRRSIG in OMNIPRESENT, and
its DS in the same state as the key in question. In human langauge,
if all keys have their DS in HIDDEN state you can do what you want,
but if a DS record is available to some validators, there must be
a chain of trust for it.

Note that the barriers on transitions first check if the current
state is valid, and then if the next state is valid too. But
here we falsely updated the 'dnskey_omnipresent' (now 'dnskey_chained')
with the next state. The next state applies to 'key' not to the state
to be checked. Updating the state here leads to (true) always, because
the key that will move its state will match the falsely updated
expected state. This could lead to the assumption that Key 2 would be
a valid chain of trust for Key 1, while clearly the presence of any
DS is uncertain.

The fix here is to check if the DNSKEY and KRRSIG are in OMNIPRESENT
state for the key that does not have its DS in the HIDDEN state, and
only if that is not the case, ensure that there is a key with the same
algorithm, that provides a valid chain of trust, that is, has its
DNSKEY, KRRSIG, and DS in OMNIPRESENT state.

The changes in 'keymgr_dnskey_hidden_or_chained()' are only cosmetical,
renaming 'rrsig_omnipresent' to 'rrsig_chained' and removing the
redundant initialization of the DST_KEY_DNSKEY expected state to NA.

(cherry picked from commit 291bcc3721)
2021-02-03 15:47:30 +01:00
Matthijs Mekking
6ff0e99fa7 Update keymgr_key_is_successor() calls
The previous commit changed the function definition of
'keymgr_key_is_successor()', this commit updates the code where
this function is called.

In 'keymgr_key_exists_with_state()' the logic is also updated slightly
to become more readable. First handle the easy cases:
- If the key does not match the state, continue with the next key.
- If we found a key with matching state, and there is no need to
  check the successor relationship, return (true).
- Otherwise check the successor relationship.

In 'keymgr_key_has_successor()' it is enough to check if a key has
a direct successor, so instead of calling 'keymgr_key_is_successor()',
we can just check 'keymgr_direct_dep()'.

In 'dns_keymgr_run()', we want to make sure that there is no
dependency on the keys before retiring excess keys, so replace
'keymgr_key_is_successor()' with 'keymgr_dep()'.

(cherry picked from commit 600915d1b2)
2021-02-03 15:47:23 +01:00
Matthijs Mekking
5e40515671 Implement Equation(2) of "Flexible Key Rollover"
So far the key manager could only deal with two keys in a rollover,
because it used a simplified version of the successor relationship
equation from "Flexible and Robust Key Rollover" paper. The simplified
version assumes only two keys take part in the key rollover and it
for that it is enough to check the direct relationship between two
keys (is key x the direct predecessor of key z and is key z the direct
successor of key x?).

But when a third key (or more keys) comes into the equation, the key
manager would assume that one key (or more) is redundant and removed
it from the zone prematurely.

Fix by implementing Equation(2) correctly, where we check for
dependencies on keys:

z ->T x: Dep(x, T) = ∅ ∧
         (x ∈ Dep(z, T) ∨
          ∃ y ∈ Dep(z, T)(y != z ∧ y ->T x ∧ DyKyRySy = DzKzRzSz))

This says: key z is a successor of key x if:
- key x depends on key z if z is a direct successor of x,
- or if there is another key y that depends on key z that has identical
  key states as key z and key y is a successor of key x.
- Also, key x may not have any other keys depending on it.

This is still a simplified version of Equation(2) (but at least much
better), because the paper allows for a set of keys to depend on a
key. This is defined as the set Dep(x, T). Keys in the set Dep(x, T)
have a dependency on key x for record type T. The BIND implementation
can only have one key in the set Dep(x, T). The function
'keymgr_dep()' stores this key in 'uint32_t *dep' if there is a
dependency.

There are two scenarios where multiple keys can depend on a single key:

1. Rolling keys is faster than the time required to finish the
   rollover procedure. This scenario is covered by the recursive
   implementation, and checking for a chain of direct dependencies
   will suffice.

2. Changing the policy, when a zone is requested to be signed with
   a different key length for example. BIND 9 will not mark successor
   relationships in this case, but tries to move towards the new
   policy. Since there is no successor relationship, the rules are
   even more strict, and the DNSSEC reconfiguration is actually slower
   than required.

Note: this commit breaks the build, because the function definition
of 'keymgr_key_is_successor' changed. This will be fixed in the
following commit.

(cherry picked from commit cc38527b63)
2021-02-03 15:47:14 +01:00
Matthijs Mekking
3f6dafe1f4 Remove initialize goal code
Since keys now have their goals initialized in 'keymgr_key_init()',
remove this redundant piece of code in 'keymgr_key_run()'.

(cherry picked from commit 82632fa6d9)
2021-02-03 08:42:51 +01:00
Matthijs Mekking
4170288a91 Correctly initialize old key with state file
The 'key_init()' function is used to initialize a state file for keys
that don't have one yet. This can happen if you are migrating from a
'auto-dnssec' or 'inline-signing' to a 'dnssec-policy' configuration.

It did not look at the "Inactive" and "Delete" timing metadata and so
old keys left behind in the key directory would also be considered as
a possible active key. This commit fixes this and now explicitly sets
the key goal to OMNIPRESENT for keys that have their "Active/Publish"
timing metadata in the past, but their "Inactive/Delete" timing
metadata in the future. If the "Inactive/Delete" timing metadata is
also in the past, the key goal is set to HIDDEN.

If the "Inactive/Delete" timing metadata is in the past, also the
key states are adjusted to either UNRETENTIVE or HIDDEN, depending on
how far in the past the metadata is set.

(cherry picked from commit 76cf72e65a)
2021-02-03 08:42:32 +01:00
Diego Fronza
51663408bc Fix race condition on check_stale_header
This commit fix a race that could happen when two or more threads have
failed to refresh the same RRset, the threads could simultaneously
attempt to update the header->last_refresh_fail_ts field in
check_stale_header, a field used to implement stale-refresh-time.

By making this field atomic we avoid such race.

(cherry picked from commit c75575e350)
2021-01-29 15:29:00 +01:00
Matthijs Mekking
99c72bf5da Update code flow in query.c wrt stale data
First of all, there was a flaw in the code related to the
'stale-refresh-time' option. If stale answers are enabled, and we
returned stale data, then it was assumed that it was because we were
in the 'stale-refresh-time' window. But now we could also have returned
stale data because of a 'stale-answer-client-timeout'. To fix this,
introduce a rdataset attribute DNS_RDATASETATTR_STALE_WINDOW to
indicate whether the stale cache entry was returned because the
'stale-refresh-time' window is active.

Second, remove the special case handling when the result is
DNS_R_NCACHENXRRSET. This can be done more generic in the code block
when dealing with stale data.

Putting all stale case handling in the code block when dealing with
stale data makes the code more easy to follow.

Update documentation to be more verbose and to match then new code
flow.

(cherry picked from commit fa0c9280d2)
2021-01-29 10:43:41 +01:00
Diego Fronza
0e62c53c5b Extracted common function from query_lookup and query_refresh_rrset
Both functions employed the same code lines to allocate query context
buffers, which are used to store query results, so this shared portion
of code was extracted out to a new function, qctx_prepare_buffers.

Also, this commit uses qctx_init to initialize the query context whitin
query_refresh_rrset function.

(cherry picked from commit 966060c03b)
2021-01-29 10:43:27 +01:00
Diego Fronza
5cbb28a40e Small optimization in query_usestale
This commit makes the code in query_usestale easier to follow, it also
doesn't attach/detach to the database if stale answers are not enabled.

(cherry picked from commit f89ac07b28)
2021-01-29 10:41:39 +01:00
Diego Fronza
8324c3ddfe Allow stale data to be used before name resolution
This commit allows stale RRset to be used (if available) for responding
a query, before an attempt to refresh an expired, or otherwise resolve
an unavailable RRset in cache is made.

For that to work, a value of zero must be specified for
stale-answer-client-timeout statement.

To better understand the logic implemented, there are three flags being
used during database lookup and other parts of code that must be
understood:

. DNS_DBFIND_STALEOK: This flag is set when BIND fails to refresh a
  RRset due to timeout (resolver-query-timeout), its intent is to
  try to look for stale data in cache as a fallback, but only if
  stale answers are enabled in configuration.

  This flag is also used to activate stale-refresh-time window, since it
  is the only way the database knows that a resolution has failed.

. DNS_DBFIND_STALEENABLED: This flag is used as a hint to the database
  that it may use stale data. It is always set during query lookup if
  stale answers are enabled, but only effectively used during
  stale-refresh-time window. Also during this window, the resolver will
  not try to resolve the query, in other words no attempt to refresh the
  data in cache is made when the stale-refresh-time window is active.

. DNS_DBFIND_STALEONLY: This new introduced flag is used when we want
  stale data from the database, but not due to a failure in resolution,
  it also doesn't require stale-refresh-time window timer to be active.
  As long as there is a stale RRset available, it should be returned.
  It is mainly used in two situations:

    1. When stale-answer-client-timeout timer is triggered: in that case
       we want to know if there is stale data available to answer the
       client.
    2. When stale-answer-client-timeout value is set to zero: in that
       case, we also want to know if there is some stale RRset available
       to promptly answer the client.

We must also discern between three situations that may happen when
resolving a query after the addition of stale-answer-client-timeout
statement, and how to handle them:

	1. Are we running query_lookup() due to stale-answer-client-timeout
       timer being triggered?

       In this case, we look for stale data, making use of
       DNS_DBFIND_STALEONLY flag. If a stale RRset is available then
       respond the client with the data found, mark this query as
       answered (query attribute NS_QUERYATTR_ANSWERED), so when the
       fetch completes the client won't be answered twice.

       We must also take care of not detaching from the client, as a
       fetch will still be running in background, this is handled by the
       following snippet:

       if (!QUERY_STALEONLY(&client->query)) {
           isc_nmhandle_detach(&client->reqhandle);
       }

       Which basically tests if DNS_DBFIND_STALEONLY flag is set, which
       means we are here due to a stale-answer-client-timeout timer
       expiration.

    2. Are we running query_lookup() due to resolver-query-timeout being
       triggered?

       In this case, DNS_DBFIND_STALEOK flag will be set and an attempt
       to look for stale data will be made.
       As already explained, this flag is algo used to activate
       stale-refresh-time window, as it means that we failed to refresh
       a RRset due to timeout.
       It is ok in this situation to detach from the client, as the
       fetch is already completed.

    3. Are we running query_lookup() during the first time, looking for
       a RRset in cache and stale-answer-client-timeout value is set to
       zero?

       In this case, if stale answers are enabled (probably), we must do
       an initial database lookup with DNS_DBFIND_STALEONLY flag set, to
       indicate to the database that we want stale data.

       If we find an active RRset, proceed as normal, answer the client
       and the query is done.

       If we find a stale RRset we respond to the client and mark the
       query as answered, but don't detach from the client yet as an
       attempt in refreshing the RRset will still be made by means of
       the new introduced function 'query_resolve'.

       If no active or stale RRset is available, begin resolution as
       usual.

(cherry picked from commit e219422575)
2021-01-29 10:39:09 +01:00
Diego Fronza
0aebad96b5 Added option for disabling stale-answer-client-timeout
This commit allows to specify "disabled" or "off" in
stale-answer-client-timeout statement. The logic to support this
behavior will be added in the subsequent commits.

This commit also ensures an upper bound to stale-answer-client-timeout
which equals to one second less than 'resolver-query-timeout'.

(cherry picked from commit 0ad6f594f6)
2021-01-29 10:38:58 +01:00
Diego Fronza
3478794a5d Add stale-answer-client-timeout option
The general logic behind the addition of this new feature works as
folows:

When a client query arrives, the basic path (query.c / ns_query_recurse)
was to create a fetch, waiting for completion in fetch_callback.

With the introduction of stale-answer-client-timeout, a new event of
type DNS_EVENT_TRYSTALE may invoke fetch_callback, whenever stale
answers are enabled and the fetch took longer than
stale-answer-client-timeout to complete.

When an event of type DNS_EVENT_TRYSTALE triggers fetch_callback, we
must ensure that the folowing happens:

1. Setup a new query context with the sole purpose of looking up for
   stale RRset only data, for that matters a new flag was added
   'DNS_DBFIND_STALEONLY' used in database lookups.

    . If a stale RRset is found, mark the original client query as
      answered (with a new query attribute named NS_QUERYATTR_ANSWERED),
      so when the fetch completion event is received later, we avoid
      answering the client twice.

    . If a stale RRset is not found, cleanup and wait for the normal
      fetch completion event.

2. In ns_query_done, we must change this part:
	/*
	 * If we're recursing then just return; the query will
	 * resume when recursion ends.
	 */
	if (RECURSING(qctx->client)) {
		return (qctx->result);
	}

   To this:

	if (RECURSING(qctx->client) && !QUERY_STALEONLY(qctx->client)) {
		return (qctx->result);
	}

   Otherwise we would not proceed to answer the client if it happened
   that a stale answer was found when looking up for stale only data.

When an event of type DNS_EVENT_FETCHDONE triggers fetch_callback, we
proceed as before, resuming query, updating stats, etc, but a few
exceptions had to be added, most important of which are two:

1. Before answering the client (ns_client_send), check if the query
   wasn't already answered before.

2. Before detaching a client, e.g.
   isc_nmhandle_detach(&client->reqhandle), ensure that this is the
   fetch completion event, and not the one triggered due to
   stale-answer-client-timeout, so a correct call would be:
   if (!QUERY_STALEONLY(client)) {
        isc_nmhandle_detach(&client->reqhandle);
   }

Other than these notes, comments were added in code in attempt to make
these updates easier to follow.

(cherry picked from commit 171a5b7542)
2021-01-29 10:38:32 +01:00
Diego Fronza
7bf8950a0a Added dns_view_staleanswerenabled() function
Since it takes a couple lines of code to check whether stale answers
are enabled for a given view, code was extracted out to a proper
function.

(cherry picked from commit 74840ec50b)
2021-01-29 10:35:26 +01:00
Diego Fronza
f3bd27373d Avoid iterating name twice when constructing fctx->info
This is a minor performance improvement, we store the result of the
first call to strlcat to use as an offset in the next call when
constructing fctx->info string.

(cherry picked from commit 49c40827f6)
2021-01-29 10:35:17 +01:00
Mark Andrews
6a0b751555 Require 'ctx' to be non-NULL in cfg_acl_fromconfig{,2}
(cherry picked from commit a8b55992a8)
2021-01-28 13:43:47 +11:00
Mark Andrews
afc75de0cc Optimise dnssec-verify
dns_dnssec_keyfromrdata() only needs to be called once per DNSKEY
rather than once per verification attempt.

(cherry picked from commit c75b325832)
2021-01-28 12:18:31 +11:00
Mark Andrews
b416d8fcdf Improve the diagnostic 'rndc retransfer' error message
(cherry picked from commit dd3520ae41)
2021-01-28 09:44:26 +11:00
Matthijs Mekking
4a36b6d918 Make opensslecdsa_parse use fromlabel
When 'opensslecdsa_parse()' encounters a label tag in the private key
file, load the private key with 'opensslecdsa_fromlabel()'. Otherwise
load it from the private structure.

This was attempted before with 'load_privkey()' and 'uses_engine()',
but had the same flaw as 'opensslecdsa_fromlabel()' had previously,
that is getting the private and public key separately, juggling with
pointers between EC_KEY and EVP_PKEY, did not create a valid
cryptographic key that could be used for signing.

(cherry picked from commit 57ac70ad46)
2021-01-26 15:04:59 +01:00
Matthijs Mekking
97185ecac2 Simplify opensslecdsa_fromlabel
The 'opensslecdsa_fromlabel()' function does not need to get the
OpenSSL engine twice to load the private and public key. Also no need
to call 'dst_key_to_eckey()' as the EC_KEY can be derived from the
loaded EVP_PKEY's.

Add some extra checks to ensure the key has the same base id and curve
(group nid) as the dst key.

Since we already have the EVP_PKEY, no need to call 'finalize_eckey()',
instead just set the right values in the key structure.

(cherry picked from commit 393052d6ff)
2021-01-26 15:04:51 +01:00
Matthijs Mekking
f555cec0af Replace EVP_DigestFinal with EVP_DigestFinal_ex
The openssl docs claim that EVP_DigestFinal() is obsolete and that
one should use EVP_DigestFinal_ex() instead.

(cherry picked from commit 1fcd0ef8bd)
2021-01-26 15:04:38 +01:00
Matthijs Mekking
9e2ea5efb1 Don't set pubkey if eckey already has public key
The 'ecdsa_check()' function tries to correctly set the public key
on the eckey, but this should be skipped if the public key is
retrieved via the private key.

(cherry picked from commit 06b9724152)
2021-01-26 15:04:21 +01:00
Matthijs Mekking
e3acfb44d5 ECDSA code should not use RSA label
The 'opensslecdsa_tofile()' function tags the label as an RSA label,
that is a copy paste error and should be of course an ECDSA label.

(cherry picked from commit 46afeca8bf)
2021-01-26 15:04:11 +01:00
Matthijs Mekking
8b25d3ab57 Correctly update pointers to pubkey and privkey
The functions 'load_pubkey_from_engine()' and
'load_privkey_from_engine()' did not correctly store the pointers.

Update both functions to add 'EC_KEY_set_public_key()' and
'EC_KEY_set_private_key()' respectively, so that the pointers to
the public and private keys survive the "load from engine" functions.

(cherry picked from commit 01239691a1)
2021-01-26 15:04:03 +01:00
Matthijs Mekking
f66df9f1b7 load_pubkey_from_engine() should load public key
The 'function load_pubkey_from_engine()' made a call to the libssl
function 'ENGINE_load_private_key'.  This is a copy paste error and
should be 'ENGINE_load_public_key'.

(cherry picked from commit 370285a62d)
2021-01-26 15:03:43 +01:00
Evan Hunt
077e2c2a74 add serial number to "transfer ended" log messages 2021-01-26 12:38:32 +01:00
Evan Hunt
2df6ffc051 check size ratio when responding to IXFR requests 2021-01-26 12:38:32 +01:00
Evan Hunt
9950247c78 improve calculation of database transfer size
- change name of 'bytes' to 'xfrsize' in dns_db_getsize() parameter list
  and related variables; this is a more accurate representation of what
  the function is doing
- change the size calculations in dns_db_getsize() to more accurately
  represent the space needed for a *XFR message or journal file to contain
  the data in the database. previously we returned the sizes of all
  rdataslabs, including header overhead and offset tables, which
  resulted in the database size being reported as much larger than the
  equivalent *XFR or journal.
- map files caused a particular problem here: the fullname can't be
  determined from the node while a file is being deserialized, because
  the uppernode pointers aren't set yet. so we store "full name length"
  in the dns_rbtnode structure while serializing, and clear it after
  deserialization is complete.
2021-01-26 12:38:32 +01:00
Evan Hunt
70df95e9f5 dns_journal_iter_init() can now return the size of the delta
the call initailizing a journal iterator can now optionally return
to the caller the size in bytes of an IXFR message (not including
DNS header overhead, signatures etc) containing the differences from
the beginning to the ending serial number.

this is calculated by scanning the journal transaction headers to
calculate the transfer size. since journal file records contain a length
field that is not included in IXFR messages, we subtract out the length
of those fields from the overall transaction length.

this necessitated adding an "RR count" field to the journal transaction
header, so we know how many length fields to subract. NOTE: this will
make existing journal files stop working!
2021-01-26 12:38:32 +01:00
Evan Hunt
57aadd6cea add syntax and setter/getter functions to configure max-ixfr-ratio 2021-01-26 12:38:32 +01:00
Ondřej Surý
0e25af628c Use -release instead of -version-info for internal library SONAMEs
The BIND 9 libraries are considered to be internal only and hence the
API and ABI changes a lot.  Keeping track of the API/ABI changes takes
time and it's a complicated matter as the safest way to make everything
stable would be to bump any library in the dependency chain as in theory
if libns links with libdns, and a binary links with both, and we bump
the libdns SOVERSION, but not the libns SOVERSION, the old libns might
be loaded by binary pulling old libdns together with new libdns loaded
by the binary.  The situation gets even more complicated with loading
the plugins that have been compiled with few versions old BIND 9
libraries and then dynamically loaded into the named.

We are picking the safest option possible and usable for internal
libraries - instead of using -version-info that has only a weak link to
BIND 9 version number, we are using -release libtool option that will
embed the corresponding BIND 9 version number into the library name.

That means that instead of libisc.so.1608 (as an example) the library
will now be named libisc-9.16.10.so.

(cherry picked from commit c605d75ea5)
2021-01-25 15:28:09 +01:00
Tinderbox User
536bc1163a prep 9.16.11 2021-01-21 09:11:54 +01:00
Evan Hunt
1a32a4d001 prevent "primaries" lists from having duplicate names
it is now an error to have two primaries lists with the same
name. this is true regardless of whether the "primaries" or
"masters" keywords were used to define them.

(cherry picked from commit f619708bbf)
2021-01-12 15:21:14 +01:00
Evan Hunt
746aa2581c add "primary-only" as a synonym for "master-only"
update the "notify" option to use RFC 8499 terminology as well.

(cherry picked from commit 424a3cf3cc)
2021-01-12 15:21:14 +01:00
Evan Hunt
04b9cdb53c add "primaries" as a synonym for "masters" in named.conf
as "type primary" is preferred over "type master" now, it makes
sense to make "primaries" available as a synonym too.

added a correctness check to ensure "primaries" and "masters"
cannot both be used in the same zone.

(cherry picked from commit 16e14353b1)
2021-01-12 15:21:14 +01:00
Matthijs Mekking
c4520620dc Fix signatures-validity config option
KASP was using 'signatures-validity-dnskey' instead of
'signatures-validity'.

(cherry picked from commit ad63e9e4f8)
2021-01-12 13:13:05 +01:00
Mark Andrews
07e899f616 Inactive incorrectly incremented
It is possible to have two threads destroying an rbtdb at the same
time when detachnode() executes and removes the last reference to
a node between exiting being set to true for the node and testing
if the references are zero in maybe_free_rbtdb().  Move NODE_UNLOCK()
to after checking if references is zero to prevent detachnode()
changing the reference count too early.

(cherry picked from commit 859d2fdad6)
2021-01-06 16:33:32 +11:00
Matthijs Mekking
63e58f09a5 Fix dnssec-signzone and -verify logging (again)
While fixing #2359, 'report()' was changed so that it would print the
newline.

Newlines were missing from the output of 'dnssec-signzone'
and 'dnssec-verify' because change
664b8f04f5 moved the printing from
newlines to the library.

This had to be reverted because this also would print redundant
newlines in logfiles.

While doing the revert, some newlines in 'lib/dns/zoneverify.c'
were left in place, now making 'dnssec-signzone' and 'dnssec-verify'
print too many newlines.

This commit removes those newlines, so that the output looks nice
again.

(cherry picked from commit 18c62a077e)
2021-01-05 13:41:49 +01:00
Matthijs Mekking
d564ad5f52 Update keymgr to allow transition to insecure mode
The keymgr prevented zones from going to insecure mode. If we
have a policy with an empty key list this is a signal that the zone
wants to go back to insecure mode. In this case allow one extra state
transition to be valid when checking for DNSSEC safety.

(cherry picked from commit 9134100069)
2020-12-23 11:56:54 +01:00
Matthijs Mekking
6da379d844 Publish CDS/CDNSKEY Delete Records
Check if zone is transitioning from secure to insecure. If so,
delete the CDS/CDNSKEY records, otherwise make sure they are not
part of the RRset.

(cherry picked from commit 68d715a229)
2020-12-23 11:56:44 +01:00
Matthijs Mekking
cf0439cd5f Treat dnssec-policy "none" as a builtin zone
Configure "none" as a builtin policy. Change the 'cfg_kasp_fromconfig'
api so that the 'name' will determine what policy needs to be
configured.

When transitioning a zone from secure to insecure, there will be
cases when a zone with no DNSSEC policy (dnssec-policy none) should
be using KASP. When there are key state files available, this is an
indication that the zone once was DNSSEC signed but is reconfigured
to become insecure.

If we would not run the keymgr, named would abruptly remove the
DNSSEC records from the zone, making the zone bogus. Therefore,
change the code such that a zone will use kasp if there is a valid
dnssec-policy configured, or if there are state files available.

(cherry picked from commit cf420b2af0)
2020-12-23 11:56:33 +01:00
Matthijs Mekking
6ff69ee8ba Add function to see if dst key uses kasp
For purposes of zones transitioning back to insecure mode, it is
practical to see if related keys have a state file associated.

(cherry picked from commit 8f2c5e45da)
2020-12-23 11:56:25 +01:00
Mark Andrews
4d003dd0f8 Only pick CPUs that are part of the existing CPU affinity set when
assigning a thread to a CPU.

(cherry picked from commit 698d9285d4)
2020-12-23 09:21:29 +11:00
Ondřej Surý
04f9f45c54 Print warning when falling back to increment soa serial method
When using the `unixtime` or `date` method to update the SOA serial,
`named` and `dnssec-signzone` would silently fallback to `increment`
method to prevent the new serial number to be smaller than the old
serial number (using the serial number arithmetics).  Add a warning
message when such fallback happens.

(cherry picked from commit ef685bab5c)
2020-12-12 07:55:29 +01:00
Ondřej Surý
2c04299eb1 Fix HAVE_SO_REUSEPORT_LB macro name definition
A typo in macro definition caused the load-balanced sockets to be
disabled even on platforms with existing support for load-balanced
sockets.

(cherry picked from commit 5caf33feda)
2020-12-09 10:46:16 +01:00
Ondřej Surý
90979a79e2 Sync the func() -> func(void) in netmgr 2020-12-09 10:46:16 +01:00
Ondřej Surý
bb9b55dfba Use sock->nchildren instead of mgr->nworkers when initializing NM
On Windows, we were limiting the number of listening children to just 1,
but we were then iterating on mgr->nworkers.  That lead to scheduling
more async_*listen() than actually allocated and out-of-bound read-write
operation on the heap.

(cherry picked from commit 87c5867202)
2020-12-09 10:46:16 +01:00
Ondřej Surý
857704b879 Explicitly link the netmgr tests with -luv 2020-12-09 10:46:16 +01:00
Ondřej Surý
7ec4ec3a81 Fix datarace when UDP/TCP connect fails and we are in nmthread
When we were in nmthread, the isc__nm_async_<proto>connect() function
executes in the same thread as the isc__nm_<proto>connect() and on a
failure, it would block indefinitely because the failure branch was
setting sock->active to false before the condition around the wait had a
chance to skip the WAIT().

This also fixes the zero system test being stuck on FreeBSD 11, so we
re-enable the test in the commit.
2020-12-09 10:46:16 +01:00
Ondřej Surý
90a9b0611a Add FreeBSD connection timeout socket option
On FreeBSD, the option to configure connection timeout is called
TCP_KEEPINIT, use it to configure the connection timeout there.

This also fixes the dangling socket problems in the unit test, so
re-enable them.
2020-12-09 10:46:16 +01:00
Ondřej Surý
0ee8672692 Distribute queries among threads even on platforms without lb sockets
On platforms without load-balancing socket all the queries would be
handle by a single thread.  Currently, the support for load-balanced
sockets is present in Linux with SO_REUSEPORT and FreeBSD 12 with
SO_REUSEPORT_LB.

This commit adds workaround for such platforms that:

1. setups single shared listening socket for all listening nmthreads for
   UDP, TCP and TCPDNS netmgr transports

2. Calls uv_udp_bind/uv_tcp_bind on the underlying socket just once and
   for rest of the nmthreads only copy the internal libuv flags (should
   be just UV_HANDLE_BOUND and optionally UV_HANDLE_IPV6).

3. start reading on UDP socket or listening on TCP socket

The load distribution among the nmthreads is uneven, but it's still
better than utilizing just one thread for processing all the incoming
queries
2020-12-09 10:46:16 +01:00
Ondřej Surý
4c70100ce0 Don't use stack allocated buffer for uv_write()
On FreeBSD, the stack is destroyed more aggressively than on Linux and
that revealed a bug where we were allocating the 16-bit len for the
TCPDNS message on the stack and the buffer got garbled before the
uv_write() sendback was executed.  Now, the len is part of the uvreq, so
we can safely pass it to the uv_write() as the req gets destroyed after
the sendcb is executed.

(cherry picked from commit 94afea9325)
2020-12-09 10:46:16 +01:00
Michał Kępień
12fa8a7aed Make netmgr initialize and cleanup Winsock itself
On Windows, WSAStartup() needs to be called to initialize Winsock before
any sockets are created or else socket() calls will return error code
10093 (WSANOTINITIALISED).  Since BIND's Network Manager is intended to
work as a reusable networking library, it should take care of calling
WSAStartup() - and its cleanup counterpart, WSACleanup() - itself rather
than relying on external code to do it.  Add the necessary WSAStartup()
and WSACleanup() calls to isc_nm_start() and isc_nm_destroy(),
respectively.

(cherry picked from commit 88f96faba8)
2020-12-09 10:46:16 +01:00
Michał Kępień
216fc34490 Extend log message for unexpected socket() errors
Make sure the error code is included in the message logged for
unexpected socket creation errors in order to facilitate troubleshooting
on Windows.

(cherry picked from commit dc2e1dea86)
2020-12-09 10:46:16 +01:00
Ondřej Surý
e8e8ed7fb9 Adjust the nstests for isc_nmhandle_{attach,detach} name change
Due to the added attach/detach tracing in the netmgr-v2 code, the
libns tests needs to be adjusted as the real function names have
changed from isc_nmhandle_* to isc__nmhandle_*.
2020-12-09 10:46:16 +01:00
Ondřej Surý
9b2184893d The cmocka.h header MUST be included before isc/util.h gets included
The isc/util.h header redefine the DbC checks (REQUIRE, INSIST, ...)  to
be cmocka "fake" assertions.  However that means that cmocka.h needs to
be included after UNIT_TESTING is defined but before isc/util.h is
included.  Because isc/util.h is included in most of the project headers
this means that the sequence MUST be:

    #define UNIT_TESTING
    #include <cmocka.h>

    #include <isc/_anything_.h>

See !2204 for other header requirements for including cmocka.h.

(cherry picked from commit 0ba697fe8c)
2020-12-09 10:46:16 +01:00
Ondřej Surý
7fc62f829d Add libssl libraries to Windows build
This commit extends the perl Configure script to also check for libssl
in addition to libcrypto and change the vcxproj source files to link
with both libcrypto and libssl.
2020-12-09 10:46:16 +01:00
Ondřej Surý
48759bd047 Fix the data race in accessing the isc_nm_t timers
The following TSAN report about accessing the mgr timers (mgr->init,
mgr->idle, mgr->keepalive and mgr->advertised) has been fixed in this
commit:

    ==================
    WARNING: ThreadSanitizer: data race (pid=2746)
    Read of size 4 at 0x7b440008a948 by thread T18:
    #0 isc__nm_tcpdns_read /home/ondrej/Projects/bind9/lib/isc/netmgr/tcpdns.c:849:25 (libisc.so.1706+0x2ba0f)
    #1 isc_nm_read /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:1679:3 (libisc.so.1706+0x22258)
    #2 tcpdns_connect_connect_cb /home/ondrej/Projects/bind9/lib/isc/tests/tcpdns_test.c:363:2 (tcpdns_test+0x4bc5fb)
    #3 isc__nm_async_connectcb /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:1816:2 (libisc.so.1706+0x228c9)
    #4 isc__nm_connectcb /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:1791:3 (libisc.so.1706+0x22713)
    #5 tcpdns_connect_cb /home/ondrej/Projects/bind9/lib/isc/netmgr/tcpdns.c:343:2 (libisc.so.1706+0x2d89d)
    #6 uv__stream_connect /home/ondrej/Projects/tsan/libuv/src/unix/stream.c:1381:5 (libuv.so.1+0x27c18)
    #7 uv__stream_io /home/ondrej/Projects/tsan/libuv/src/unix/stream.c:1298:5 (libuv.so.1+0x25977)
    #8 uv__io_poll /home/ondrej/Projects/tsan/libuv/src/unix/linux-core.c:462:11 (libuv.so.1+0x2e795)
    #9 uv_run /home/ondrej/Projects/tsan/libuv/src/unix/core.c:385:5 (libuv.so.1+0x158ec)
    #10 nm_thread /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:530:11 (libisc.so.1706+0x1c94a)

    Previous write of size 4 at 0x7b440008a948 by main thread:
    #0 isc_nm_settimeouts /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:490:12 (libisc.so.1706+0x1dda5)
    #1 tcpdns_recv_two /home/ondrej/Projects/bind9/lib/isc/tests/tcpdns_test.c:601:2 (tcpdns_test+0x4bad0e)
    #2 cmocka_run_one_test_or_fixture <null> (libcmocka.so.0+0x70be)
    #3 __libc_start_main /build/glibc-vjB4T1/glibc-2.28/csu/../csu/libc-start.c:308:16 (libc.so.6+0x2409a)

    Location is heap block of size 281 at 0x7b440008a840 allocated by main thread:
    #0 malloc <null> (tcpdns_test+0x42864b)
    #1 default_memalloc /home/ondrej/Projects/bind9/lib/isc/mem.c:713:8 (libisc.so.1706+0x6d261)
    #2 mem_get /home/ondrej/Projects/bind9/lib/isc/mem.c:622:8 (libisc.so.1706+0x69b9c)
    #3 isc___mem_get /home/ondrej/Projects/bind9/lib/isc/mem.c:1044:9 (libisc.so.1706+0x6d379)
    #4 isc__mem_get /home/ondrej/Projects/bind9/lib/isc/mem.c:2432:10 (libisc.so.1706+0x6889e)
    #5 isc_nm_start /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:203:8 (libisc.so.1706+0x1c219)
    #6 nm_setup /home/ondrej/Projects/bind9/lib/isc/tests/tcpdns_test.c:244:11 (tcpdns_test+0x4baaa4)
    #7 cmocka_run_one_test_or_fixture <null> (libcmocka.so.0+0x70fd)
    #8 __libc_start_main /build/glibc-vjB4T1/glibc-2.28/csu/../csu/libc-start.c:308:16 (libc.so.6+0x2409a)

    Thread T18 'isc-net-0000' (tid=3513, running) created by main thread at:
    #0 pthread_create <null> (tcpdns_test+0x429e7b)
    #1 isc_thread_create /home/ondrej/Projects/bind9/lib/isc/pthreads/thread.c:73:8 (libisc.so.1706+0x8476a)
    #2 isc_nm_start /home/ondrej/Projects/bind9/lib/isc/netmgr/netmgr.c:271:3 (libisc.so.1706+0x1c66a)
    #3 nm_setup /home/ondrej/Projects/bind9/lib/isc/tests/tcpdns_test.c:244:11 (tcpdns_test+0x4baaa4)
    #4 cmocka_run_one_test_or_fixture <null> (libcmocka.so.0+0x70fd)
    #5 __libc_start_main /build/glibc-vjB4T1/glibc-2.28/csu/../csu/libc-start.c:308:16 (libc.so.6+0x2409a)

    SUMMARY: ThreadSanitizer: data race /home/ondrej/Projects/bind9/lib/isc/netmgr/tcpdns.c:849:25 in isc__nm_tcpdns_read
    ==================
    ThreadSanitizer: reported 1 warnings

(cherry picked from commit 2e1dd56d0b)
2020-12-09 10:46:16 +01:00
Ondřej Surý
a61b7294c2 Avoid netievent allocations when the callbacks can be called directly
After turning the users callbacks to be asynchronous, there was a
visible performance drop.  This commit prevents the unnecessary
allocations while keeping the code paths same for both asynchronous and
synchronous calls.

The same change was done to the isc__nm_udp_{read,send} as those two
functions are in the hot path.

(cherry picked from commit d6d2fbe0e9)
2020-12-09 10:46:16 +01:00
Ondřej Surý
7b9c8b9781 Refactor netmgr and add more unit tests
This is a part of the works that intends to make the netmgr stable,
testable, maintainable and tested.  It contains a numerous changes to
the netmgr code and unfortunately, it was not possible to split this
into smaller chunks as the work here needs to be committed as a complete
works.

NOTE: There's a quite a lot of duplicated code between udp.c, tcp.c and
tcpdns.c and it should be a subject to refactoring in the future.

The changes that are included in this commit are listed here
(extensively, but not exclusively):

* The netmgr_test unit test was split into individual tests (udp_test,
  tcp_test, tcpdns_test and newly added tcp_quota_test)

* The udp_test and tcp_test has been extended to allow programatic
  failures from the libuv API.  Unfortunately, we can't use cmocka
  mock() and will_return(), so we emulate the behaviour with #define and
  including the netmgr/{udp,tcp}.c source file directly.

* The netievents that we put on the nm queue have variable number of
  members, out of these the isc_nmsocket_t and isc_nmhandle_t always
  needs to be attached before enqueueing the netievent_<foo> and
  detached after we have called the isc_nm_async_<foo> to ensure that
  the socket (handle) doesn't disappear between scheduling the event and
  actually executing the event.

* Cancelling the in-flight TCP connection using libuv requires to call
  uv_close() on the original uv_tcp_t handle which just breaks too many
  assumptions we have in the netmgr code.  Instead of using uv_timer for
  TCP connection timeouts, we use platform specific socket option.

* Fix the synchronization between {nm,async}_{listentcp,tcpconnect}

  When isc_nm_listentcp() or isc_nm_tcpconnect() is called it was
  waiting for socket to either end up with error (that path was fine) or
  to be listening or connected using condition variable and mutex.

  Several things could happen:

    0. everything is ok

    1. the waiting thread would miss the SIGNAL() - because the enqueued
       event would be processed faster than we could start WAIT()ing.
       In case the operation would end up with error, it would be ok, as
       the error variable would be unchanged.

    2. the waiting thread miss the sock->{connected,listening} = `true`
       would be set to `false` in the tcp_{listen,connect}close_cb() as
       the connection would be so short lived that the socket would be
       closed before we could even start WAIT()ing

* The tcpdns has been converted to using libuv directly.  Previously,
  the tcpdns protocol used tcp protocol from netmgr, this proved to be
  very complicated to understand, fix and make changes to.  The new
  tcpdns protocol is modeled in a similar way how tcp netmgr protocol.
  Closes: #2194, #2283, #2318, #2266, #2034, #1920

* The tcp and tcpdns is now not using isc_uv_import/isc_uv_export to
  pass accepted TCP sockets between netthreads, but instead (similar to
  UDP) uses per netthread uv_loop listener.  This greatly reduces the
  complexity as the socket is always run in the associated nm and uv
  loops, and we are also not touching the libuv internals.

  There's an unfortunate side effect though, the new code requires
  support for load-balanced sockets from the operating system for both
  UDP and TCP (see #2137).  If the operating system doesn't support the
  load balanced sockets (either SO_REUSEPORT on Linux or SO_REUSEPORT_LB
  on FreeBSD 12+), the number of netthreads is limited to 1.

* The netmgr has now two debugging #ifdefs:

  1. Already existing NETMGR_TRACE prints any dangling nmsockets and
     nmhandles before triggering assertion failure.  This options would
     reduce performance when enabled, but in theory, it could be enabled
     on low-performance systems.

  2. New NETMGR_TRACE_VERBOSE option has been added that enables
     extensive netmgr logging that allows the software engineer to
     precisely track any attach/detach operations on the nmsockets and
     nmhandles.  This is not suitable for any kind of production
     machine, only for debugging.

* The tlsdns netmgr protocol has been split from the tcpdns and it still
  uses the old method of stacking the netmgr boxes on top of each other.
  We will have to refactor the tlsdns netmgr protocol to use the same
  approach - build the stack using only libuv and openssl.

* Limit but not assert the tcp buffer size in tcp_alloc_cb
  Closes: #2061

(cherry picked from commit 634bdfb16d)
2020-12-09 10:46:16 +01:00
Ondřej Surý
fa9ca83862 Turn all the callback to be always asynchronous
When calling the high level netmgr functions, the callback would be
sometimes called synchronously if we catch the failure directly, or
asynchronously if it happens later.  The synchronous call to the
callback could create deadlocks as the caller would not expect the
failed callback to be executed directly.

(cherry picked from commit a49d88568f)
2020-12-09 10:46:16 +01:00
Ondřej Surý
bcc9ad98ea netmgr: Add additional safeguards to netmgr/tls.c
This commit adds couple of additional safeguards against running
sends/reads on inactive sockets.  The changes was modeled after the
changes we made to netmgr/tcpdns.c

(cherry picked from commit fa424225af)
2020-12-09 10:46:16 +01:00
Witold Kręcicki
b83dff0585 isc_nm_tls_create_server_ctx can create ephemeral certs
In-memory ephemeral certs creation for easy DoT/DoH deployment.

(cherry picked from commit 3c00fb71db)
2020-12-09 10:46:16 +01:00
Witold Kręcicki
d7fa046a69 Add DoT support to bind
Parse the configuration of tls objects into SSL_CTX* objects.  Listen on
DoT if 'tls' option is setup in listen-on directive.  Use DoT/DoH ports
for DoT/DoH.

(cherry picked from commit 38b78f59a0)
2020-12-09 10:46:16 +01:00
Evan Hunt
0f5fff5c1e report peer address in TLS mode, and specify protocol
- peer address was not being reported correctly by "dig +tls"
- the protocol used is now reported in the dig output: UDP, TCP, or TLS.

(cherry picked from commit 8886569e9d)
2020-12-09 10:46:16 +01:00
Witold Kręcicki
4a854da141 netmgr: server-side TLS support
Add server-side TLS support to netmgr - that includes moving some of the
isc_nm_ functions from tcp.c to a wrapper in netmgr.c calling a proper
tcp or tls function, and a new isc_nm_listentls() function.

Add DoT support to tcpdns - isc_nm_listentlsdns().

(cherry picked from commit b2ee0e9dc3)
2020-12-09 10:46:16 +01:00
Evan Hunt
6f6f0e26ab address some possible shutdown races in xfrin
there were two failures during observed in testing, both occurring
when 'rndc halt' was run rather than 'rndc stop' - the latter dumps
zone contents to disk and presumably introduced enough delay to
prevent the races:

- a failure when the zone was shut down and called dns_xfrin_detach()
  before the xfrin had finished connecting; the connect timeout
  terminated without detaching its handle
- a failure when the tcpdns socket timer fired after the outerhandle
  had already been cleared.

this commit incidentally addresses a failure observed in mutexatomic
due to a variable having been initialized incorrectly.
2020-12-09 10:46:16 +01:00
Ondřej Surý
c4dcedd2dc netmgr: Don't crash if socket() returns an error in udpconnect
socket() call can return an error - e.g. EMFILE, so we need to handle
this nicely and not crash.

Additionally wrap the socket() call inside a platform independent helper
function as the Socket data type on Windows is unsigned integer:

> This means, for example, that checking for errors when the socket and
> accept functions return should not be done by comparing the return
> value with –1, or seeing if the value is negative (both common and
> legal approaches in UNIX). Instead, an application should use the
> manifest constant INVALID_SOCKET as defined in the Winsock2.h header
> file.

(cherry picked from commit 8af7f81d6c)
2020-12-09 10:46:16 +01:00
Ondřej Surý
21daa258a2 netmgr: Always load the result from async socket
Because we use result earlier for setting the loadbalancing on the
socket, we could be left with a ISC_R_NOTIMPLEMENTED value stored in the
variable and when the UDP connection would succeed, we would
errorneously return this value instead of ISC_R_SUCCESS.

(cherry picked from commit 050258bda4)
2020-12-09 10:46:16 +01:00
Evan Hunt
70e08cab6b dig: use new netmgr timeout mechanism
use isc_nmhandle_settimeout() to set read/recv timeouts, and get rid
of connect_timeout() and related functions in dighost.c.

(cherry picked from commit ea2b04c361)
2020-12-09 10:46:16 +01:00
Evan Hunt
4598d7b30d add isc_nmhandle_settimeout() function
this function sets the read timeout for the socket associated
with a netmgr handle and, if the timer is running, resets it.
for TCPDNS sockets it also sets the read timeout and resets the
timer on the outer TCP socket.

(cherry picked from commit 4be63c5b00)
2020-12-09 10:46:16 +01:00