Merge branch 'fanf-urcu' into 'main'

Build with liburcu, userspace RCU

Closes #3935

See merge request isc-projects/bind9!7662

.clang-format

@@ -34,6 +34,10 @@ PointerAlignment: Right
 PointerBindsToType: false
 IncludeBlocks: Regroup
 IncludeCategories:
+  - Regex:           '^<(urcu\.h|urcu/urcu-|urcu-)'
+    Priority:        2
+  - Regex:           '^<urcu/'
+    Priority:        3
   - Regex:           '^<isc/'
     Priority:        5
   - Regex:           '^<(pk11|pkcs11)/'
@@ -59,9 +63,9 @@ IncludeCategories:
   - Regex:           '^<tests/'
     Priority:        100
   - Regex:           '<openssl/'
-    Priority:        1
+    Priority:        4
   - Regex:           '<(mysql|protobuf-c)/'
-    Priority:        1
+    Priority:        4
   - Regex:           '.*'
     Priority:        0
 IndentExternBlock: NoIndent
@@ -74,3 +78,4 @@ PenaltyBreakString: 80
 PenaltyExcessCharacter: 100
 Standard: Cpp11
 ContinuationIndentWidth: 8
+ForEachMacros: [ 'cds_lfs_for_each', 'cds_lfs_for_each_safe', 'cds_list_for_each_entry_safe' ]

.clang-format.headers

@@ -34,24 +34,40 @@ PointerAlignment: Right
 PointerBindsToType: false
 IncludeBlocks: Regroup
 IncludeCategories:
-  - Regex:           '^<isc/'
+  - Regex:           '^<(urcu/urcu-|urcu-)'
     Priority:        2
-  - Regex:           '^<dns/'
+  - Regex:           '^<urcu/'
     Priority:        3
-  - Regex:           '^<iscccc/'
+  - Regex:           '^<isc/'
-    Priority:        4
-  - Regex:           '^<isccfg/'
     Priority:        5
-  - Regex:           '^<ns/'
+  - Regex:           '^<(pk11|pkcs11)/'
-    Priority:        6
-  - Regex:           '^(<[^/]*)/)'
-    Priority:        8
-  - Regex:           '^<tests/'
     Priority:        10
-  - Regex:           '<[[:alnum:].]+>'
+  - Regex:           '^<dns/'
-    Priority:        1
+    Priority:        15
-  - Regex:           '".*"'
+  - Regex:           '^<dst/'
-    Priority:        9
+    Priority:        20
+  - Regex:           '^<isccc/'
+    Priority:        25
+  - Regex:           '^<isccfg/'
+    Priority:        30
+  - Regex:           '^<ns/'
+    Priority:        35
+  - Regex:           '^<irs/'
+    Priority:        40
+  - Regex:           '^<(dig|named|rndc|confgen|dlz)/'
+    Priority:        50
+  - Regex:           '^<dlz_'
+    Priority:        55
+  - Regex:           '^".*"'
+    Priority:        99
+  - Regex:           '^<tests/'
+    Priority:        100
+  - Regex:           '<openssl/'
+    Priority:        4
+  - Regex:           '<(mysql|protobuf-c)/'
+    Priority:        4
+  - Regex:           '.*'
+    Priority:        0
 IndentExternBlock: NoIndent
 KeepEmptyLinesAtTheStartOfBlocks: false
 MaxEmptyLinesToKeep: 1

CHANGES

@@ -1,3 +1,8 @@
+6122.	[func]		BIND now requires liburcu for lock-free data structures
+			and concurrent safe memory reclamation. It replaces the
+			home-grown lock-free linked list and QSBR machinery
+			added in changes 6108 and 6109.  [GL #3935]
+
 6121.	[cleanup]	Remove support for TKEY Mode 2 (Diffie-Hellman Exchanged
 			Keying). [GL #3905]
 

bin/named/include/named/control.h

@@ -20,9 +20,10 @@
 
 #include <stdbool.h>
 
+#include <isccc/types.h>
+
 #include <isccfg/aclconf.h>
 
-#include <isccc/types.h>
 #include <named/types.h>
 
 #define NAMED_CONTROL_PORT 953

bin/named/include/named/globals.h

@@ -26,10 +26,11 @@
 #include <dns/acl.h>
 #include <dns/zone.h>
 
+#include <dst/dst.h>
+
 #include <isccfg/aclconf.h>
 #include <isccfg/cfg.h>
 
-#include <dst/dst.h>
 #include <named/fuzz.h>
 #include <named/types.h>
 

bin/named/include/named/statschannel.h

@@ -18,9 +18,10 @@
  * The statistics channels built-in the name server.
  */
 
+#include <isccc/types.h>
+
 #include <isccfg/aclconf.h>
 
-#include <isccc/types.h>
 #include <named/types.h>
 
 #define NAMED_STATSCHANNEL_HTTPPORT 80

configure.ac

@@ -611,6 +611,9 @@ AC_CHECK_DECLS([UV_UDP_LINUX_RECVERR], [], [], [[#include <uv.h>]])
 
 AX_RESTORE_FLAGS([libuv])
 
+# userspace-rcu (QSBR variant)
+PKG_CHECK_MODULES([LIBURCU], [liburcu-qsbr liburcu-cds])
+
 # [pairwise: --enable-doh --with-libnghttp2=auto, --enable-doh --with-libnghttp2=yes, --disable-doh]
 AC_ARG_ENABLE([doh],
 	      [AS_HELP_STRING([--disable-doh], [disable DNS over HTTPS, removes dependency on libnghttp2 (default is --enable-doh)])],

contrib/dlz/modules/include/dlz_minimal.h

@@ -25,13 +25,12 @@
 
 #pragma once
 
-#include <inttypes.h>
-#include <stdbool.h>
-#include <stdlib.h>
-
 #include <arpa/inet.h>
+#include <inttypes.h>
 #include <net/if.h>
 #include <netinet/in.h>
+#include <stdbool.h>
+#include <stdlib.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <sys/un.h>

doc/arm/build.inc.rst

@@ -56,6 +56,7 @@ Required Libraries
 To build BIND 9, the following packages must be installed:
 
 - ``libcrypto``, ``libssl``
+- ``liburcu``
 - ``libuv``
 - ``perl``
 - ``pkg-config`` / ``pkgconfig`` / ``pkgconf``
@@ -73,6 +74,9 @@ in a nonstandard location, specify the prefix using
 PKCS#11 hardware service module for cryptographic operations,
 ``engine_pkcs11`` from the OpenSC project must be compiled and used.
 
+The Userspace RCU library ``liburcu`` (https://liburcu.org/) is used
+for lock-free data structures and concurrent safe memory reclamation.
+
 On Linux, process capabilities are managed in user space using the
 ``libcap`` library
 (https://git.kernel.org/pub/scm/libs/libcap/libcap.git/), which can be

doc/notes/notes-current.rst

@@ -20,13 +20,12 @@ Security Fixes
 New Features
 ~~~~~~~~~~~~
 
-- None.
+- BIND now depends on ``liburcu``, Userspace RCU, for lock-free data
+  structures. :gl:`#3934`
 
 Removed Features
 ~~~~~~~~~~~~~~~~
 
-- None.
-
 - The TKEY Mode 2 (Diffie-Hellman Exchanged Keying Mode) has been removed and
   using TKEY Mode 2 is now a fatal error.  Users are advised to switch to TKEY
   Mode 3 (GSS-API). :gl:`#3905`

lib/dns/include/dns/librpz.h

@@ -36,13 +36,12 @@
 
 #pragma once
 
+#include <arpa/nameser.h>
 #include <inttypes.h>
+#include <netinet/in.h>
 #include <stdarg.h>
 #include <stdbool.h>
 #include <stdio.h>
-
-#include <arpa/nameser.h>
-#include <netinet/in.h>
 #include <sys/types.h>
 
 /*

lib/dns/include/dns/resolver.h

@@ -46,6 +46,7 @@
  */
 
 #include <inttypes.h>
+#include <netinet/in.h>
 #include <stdbool.h>
 
 #include <isc/lang.h>
@@ -58,8 +59,6 @@
 #include <dns/fixedname.h>
 #include <dns/types.h>
 
-#include <netinet/in.h>
-
 #undef DNS_RESOLVER_TRACE
 
 ISC_LANG_BEGINDECLS

lib/isc/Makefile.am

@@ -212,6 +212,7 @@ endif USE_ISC_RWLOCK
 libisc_la_CPPFLAGS =		\
 	$(AM_CPPFLAGS)		\
 	$(LIBISC_CFLAGS)	\
+	$(LIBURCU_CFLAGS)	\
 	$(LIBUV_CFLAGS)		\
 	$(OPENSSL_CFLAGS)	\
 	$(ZLIB_CFLAGS)
@@ -221,6 +222,7 @@ libisc_la_LDFLAGS =		\
 	-release "$(PACKAGE_VERSION)"
 
 libisc_la_LIBADD =		\
+	$(LIBURCU_LIBS)		\
 	$(LIBUV_LIBS)		\
 	$(OPENSSL_LIBS)		\
 	$(ZLIB_LIBS)

lib/isc/include/isc/dir.h

@@ -17,12 +17,11 @@
 
 #include <dirent.h>
 #include <limits.h>
+#include <sys/types.h> /* Required on some systems. */
 
 #include <isc/lang.h>
 #include <isc/result.h>
 
-#include <sys/types.h> /* Required on some systems. */
-
 #ifndef NAME_MAX
 #define NAME_MAX 256
 #endif

lib/isc/include/isc/file.h

@@ -17,12 +17,11 @@
 
 #include <stdbool.h>
 #include <stdio.h>
+#include <sys/stat.h>
 
 #include <isc/lang.h>
 #include <isc/types.h>
 
-#include <sys/stat.h>
-
 ISC_LANG_BEGINDECLS
 
 isc_result_t

lib/isc/include/isc/net.h

@@ -65,17 +65,16 @@
 /***
  *** Imports.
  ***/
-#include <inttypes.h>
-
-#include <isc/lang.h>
-#include <isc/types.h>
-
 #include <arpa/inet.h> /* Contractual promise. */
+#include <inttypes.h>
 #include <net/if.h>
 #include <netinet/in.h> /* Contractual promise. */
 #include <sys/socket.h> /* Contractual promise. */
 #include <sys/types.h>
 
+#include <isc/lang.h>
+#include <isc/types.h>
+
 #ifndef IN6ADDR_LOOPBACK_INIT
 #ifdef s6_addr
 /*% IPv6 address loopback init */

lib/isc/include/isc/netaddr.h

@@ -17,14 +17,13 @@
 
 #include <inttypes.h>
 #include <stdbool.h>
+#include <sys/types.h>
+#include <sys/un.h>
 
 #include <isc/lang.h>
 #include <isc/net.h>
 #include <isc/types.h>
 
-#include <sys/types.h>
-#include <sys/un.h>
-
 ISC_LANG_BEGINDECLS
 
 /*

lib/isc/include/isc/netmgr.h

@@ -13,6 +13,8 @@
 
 #pragma once
 
+#include <sys/socket.h>
+#include <sys/types.h>
 #include <unistd.h>
 
 #include <isc/mem.h>
@@ -21,9 +23,6 @@
 #include <isc/tls.h>
 #include <isc/types.h>
 
-#include <sys/socket.h>
-#include <sys/types.h>
-
 #undef ISC_NETMGR_TRACE
 
 #if defined(SO_REUSEPORT_LB) || (defined(SO_REUSEPORT) && defined(__linux__))

lib/isc/include/isc/sockaddr.h

@@ -16,13 +16,12 @@
 /*! \file isc/sockaddr.h */
 
 #include <stdbool.h>
+#include <sys/un.h>
 
 #include <isc/lang.h>
 #include <isc/net.h>
 #include <isc/types.h>
 
-#include <sys/un.h>
-
 /*
  * Any updates to this structure should also be applied in
  * contrib/modules/dlz/dlz_minmal.h.

lib/isccc/include/isccc/cc.h

@@ -38,6 +38,7 @@
 #include <isc/lang.h>
 
 #include <dst/dst.h>
+
 #include <isccc/types.h>
 
 ISC_LANG_BEGINDECLS