nss: Export nscd hash function as __nss_hash [BZ #22459]

12 files changed, 128 insertions, 107 deletions

diff --git a/ChangeLog b/ChangeLog
index 18b2aa9561..d9222a58d2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,23 @@
 2017-11-23  Florian Weimer  <fweimer@redhat.com>
 
+	[BZ #22459]
+	Export nscd hash function as __nss_hash.
+	* include/nss.h (__nss_hash): Declare.
+	* nis/nis_hash.c (__nis_hash): Call __nss_hash.  Turn into compat
+	symbol.
+	* nscd/Makefile (aux, nscd-modules): Remove nscd_hash.
+	* nscd/cache.c (cache_search, cache_add): Call __nss_hash instead
+	of __nscd_hash.
+	* nscd/nscd_helper.c (__nscd_cache_search): Likewise.
+	* nscd/nscd_hash.h, nscd/nscd_hash.c: Remove files.
+	* nss/Makefiles (routines): Add nss_hash.
+	* nss/Versions (GLIBC_PRIVATE): Export __nss_hash.
+	* nss/nss_hash.c: Rename from nis/nis_hash.c.
+	(__nss_hash): Rename from __nis_hash.  Define hidden alias.
+	* nis/rpcsvc/nislib.h (__nis_hash): Remove declaration.
+
+2017-11-23  Florian Weimer  <fweimer@redhat.com>
+
 	[BZ #22478]
 	* sysdeps/unix/sysv/linux/sigwait.c (__sigwait): Retry on EINTR.
 	Return error code, not -1.
diff --git a/include/nss.h b/include/nss.h
index 5f29de7f84..c5b7c04c82 100644
--- a/include/nss.h
+++ b/include/nss.h
@@ -1,9 +1,12 @@
 #ifndef _NSS_H
 #include <nss/nss.h>
 
-# ifndef _ISOMAC
+#ifndef _ISOMAC
 
-#define NSS_INVALID_FIELD_CHARACTERS ":\n"
+# include <stddef.h>
+# include <stdint.h>
+
+# define NSS_INVALID_FIELD_CHARACTERS ":\n"
 extern const char __nss_invalid_field_characters[] attribute_hidden;
 
 _Bool __nss_valid_field (const char *value) attribute_hidden;
@@ -11,5 +14,10 @@ _Bool __nss_valid_list_field (char **list)  attribute_hidden;
 const char *__nss_rewrite_field (const char *value, char **to_be_freed)
   attribute_hidden;
 
-# endif /* !_ISOMAC */
+/* Compute a hash value for LENGTH bytes starting at KEY.  This is the
+   hash function used by the nscd for the cache mapping files.  */
+uint32_t __nss_hash (const void *__key, size_t __length);
+libc_hidden_proto (__nss_hash)
+
+#endif /* !_ISOMAC */
 #endif /* _NSS_H */
diff --git a/nis/nis_hash.c b/nis/nis_hash.c
index cc42ac8911..5dba1cba0f 100644
--- a/nis/nis_hash.c
+++ b/nis/nis_hash.c
@@ -1,6 +1,6 @@
-/* Copyright (c) 1997-2017 Free Software Foundation, Inc.
+/* Forward __nis_hash calls to __nss_hash, for ABI compatibility.
+   Copyright (c) 2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
-   Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997.
 
    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -16,61 +16,18 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#include <stdint.h>
-#include <rpcsvc/nis.h>
+#include <shlib-compat.h>
+
+#if SHLIB_COMPAT (libnsl, GLIBC_2_1, GLIBC_2_27)
+
+# include <nss.h>
 
-/* This is from libc/db/hash/hash_func.c, hash3 is static there */
-/*
- * This is INCREDIBLY ugly, but fast.  We break the string up into 8 byte
- * units.  On the first time through the loop we get the "leftover bytes"
- * (strlen % 8).  On every other iteration, we perform 8 HASHC's so we handle
- * all 8 bytes.  Essentially, this saves us 7 cmp & branch instructions.  If
- * this routine is heavily used enough, it's worth the ugly coding.
- *
- * OZ's original sdbm hash
- */
 uint32_t
 __nis_hash (const void *keyarg, size_t len)
 {
-  const u_char *key;
-  size_t loop;
-  uint32_t h;
+  return __nss_hash (keyarg, len);
+}
 
-#define HASHC   h = *key++ + 65599 * h
+compat_symbol (libnsl, __nis_hash, __nis_hash, GLIBC_2_1);
 
-  h = 0;
-  key = keyarg;
-  if (len > 0)
-    {
-      loop = (len + 8 - 1) >> 3;
-      switch (len & (8 - 1))
-	{
-	case 0:
-	  do {
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 7:
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 6:
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 5:
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 4:
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 3:
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 2:
-	    HASHC;
-	    /* FALLTHROUGH */
-	  case 1:
-	    HASHC;
-	  } while (--loop);
-	}
-    }
-  return h;
-}
+#endif
diff --git a/nis/rpcsvc/nislib.h b/nis/rpcsvc/nislib.h
index 52fbba4b8f..ad22c9c767 100644
--- a/nis/rpcsvc/nislib.h
+++ b/nis/rpcsvc/nislib.h
@@ -244,7 +244,6 @@ extern uint32_t __nis_default_ttl (char *) __THROW;
 extern unsigned int __nis_default_access (char *, unsigned int) __THROW;
 extern fd_result *__nis_finddirectory (directory_obj *, const_nis_name) __THROW;
 extern void __free_fdresult (fd_result *) __THROW;
-extern uint32_t __nis_hash (const void *__keyarg, size_t __len) __THROW;
 
 /* NIS+ cache locking */
 extern int __nis_lock_cache (void) __THROW;
diff --git a/nscd/Makefile b/nscd/Makefile
index 095f3e53d4..85e1c387d7 100644
--- a/nscd/Makefile
+++ b/nscd/Makefile
@@ -25,7 +25,7 @@ include ../Makeconfig
 ifneq ($(use-nscd),no)
 routines := nscd_getpw_r nscd_getgr_r nscd_gethst_r nscd_getai \
 	    nscd_initgroups nscd_getserv_r nscd_netgroup
-aux	:= nscd_helper nscd_hash
+aux	:= nscd_helper
 endif
 
 # To find xmalloc.c
@@ -36,7 +36,7 @@ nscd-modules := nscd connections pwdcache getpwnam_r getpwuid_r grpcache \
 		getsrvbynm_r getsrvbypt_r servicescache \
 		dbg_log nscd_conf nscd_stat cache mem nscd_setup_thread \
 		xmalloc xstrdup aicache initgrcache gai res_hconf \
-		netgroupcache nscd_hash
+		netgroupcache
 
 ifeq ($(build-nscd)$(have-thread-library),yesyes)
 
diff --git a/nscd/cache.c b/nscd/cache.c
index 4a17c3371b..72c73d31d3 100644
--- a/nscd/cache.c
+++ b/nscd/cache.c
@@ -29,10 +29,10 @@
 #include <sys/param.h>
 #include <sys/stat.h>
 #include <sys/uio.h>
+#include <nss.h>
 
 #include "nscd.h"
 #include "dbg_log.h"
-#include "nscd_hash.h"
 
 
 /* Wrapper functions with error checking for standard functions.  */
@@ -74,7 +74,7 @@ struct datahead *
 cache_search (request_type type, const void *key, size_t len,
 	      struct database_dyn *table, uid_t owner)
 {
-  unsigned long int hash = __nscd_hash (key, len) % table->head->module;
+  unsigned long int hash = __nss_hash (key, len) % table->head->module;
 
   unsigned long int nsearched = 0;
   struct datahead *result = NULL;
@@ -153,7 +153,7 @@ cache_add (int type, const void *key, size_t len, struct datahead *packet,
 	       first ? _(" (first)") : "");
     }
 
-  unsigned long int hash = __nscd_hash (key, len) % table->head->module;
+  unsigned long int hash = __nss_hash (key, len) % table->head->module;
   struct hashentry *newp;
 
   newp = mempool_alloc (table, sizeof (struct hashentry), 0);
diff --git a/nscd/nscd_hash.c b/nscd/nscd_hash.c
deleted file mode 100644
index 1572af616a..0000000000
--- a/nscd/nscd_hash.c
+++ /dev/null
@@ -1,19 +0,0 @@
-/* Copyright (C) 2017 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#define __nis_hash __nscd_hash
-#include <nis/nis_hash.c>
diff --git a/nscd/nscd_hash.h b/nscd/nscd_hash.h
deleted file mode 100644
index e56d71015c..0000000000
--- a/nscd/nscd_hash.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Copyright (C) 2017 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <stdint.h>
-
-extern uint32_t __nscd_hash (const void *__keyarg, size_t __len)
-  attribute_hidden;
diff --git a/nscd/nscd_helper.c b/nscd/nscd_helper.c
index a42a4a7da5..ac04a2f572 100644
--- a/nscd/nscd_helper.c
+++ b/nscd/nscd_helper.c
@@ -36,10 +36,9 @@
 #include <sys/un.h>
 #include <not-cancel.h>
 #include <kernel-features.h>
+#include <nss.h>
 
 #include "nscd-client.h"
-#include "nscd_hash.h"
-
 
 /* Extra time we wait if the socket is still receiving data.  This
    value is in milliseconds.  Note that the other side is nscd on the
@@ -451,7 +450,7 @@ struct datahead *
 __nscd_cache_search (request_type type, const char *key, size_t keylen,
 		     const struct mapped_database *mapped, size_t datalen)
 {
-  unsigned long int hash = __nscd_hash (key, keylen) % mapped->head->module;
+  unsigned long int hash = __nss_hash (key, keylen) % mapped->head->module;
   size_t datasize = mapped->datasize;
 
   ref_t trail = mapped->head->array[hash];
diff --git a/nss/Makefile b/nss/Makefile
index 26952112c1..f9ecea56a0 100644
--- a/nss/Makefile
+++ b/nss/Makefile
@@ -28,7 +28,7 @@ headers			:= nss.h
 routines		= nsswitch getnssent getnssent_r digits_dots \
 			  valid_field valid_list_field rewrite_field \
 			  $(addsuffix -lookup,$(databases)) \
-			  compat-lookup
+			  compat-lookup nss_hash
 
 # These are the databases that go through nss dispatch.
 # Caution: if you add a database here, you must add its real name
diff --git a/nss/Versions b/nss/Versions
index 7694998f1d..db8c887720 100644
--- a/nss/Versions
+++ b/nss/Versions
@@ -15,6 +15,7 @@ libc {
 
     __nss_passwd_lookup2; __nss_group_lookup2; __nss_hosts_lookup2;
     __nss_services_lookup2; __nss_next2; __nss_lookup;
+    __nss_hash;
   }
 }
 
diff --git a/nss/nss_hash.c b/nss/nss_hash.c
new file mode 100644
index 0000000000..5fb837a381
--- /dev/null
+++ b/nss/nss_hash.c
@@ -0,0 +1,79 @@
+/* Copyright (c) 1997-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <nss.h>
+
+/* This is from libc/db/hash/hash_func.c, hash3 is static there */
+/*
+ * This is INCREDIBLY ugly, but fast.  We break the string up into 8 byte
+ * units.  On the first time through the loop we get the "leftover bytes"
+ * (strlen % 8).  On every other iteration, we perform 8 HASHC's so we handle
+ * all 8 bytes.  Essentially, this saves us 7 cmp & branch instructions.  If
+ * this routine is heavily used enough, it's worth the ugly coding.
+ *
+ * OZ's original sdbm hash
+ */
+uint32_t
+__nss_hash (const void *keyarg, size_t len)
+{
+  const unsigned char *key;
+  size_t loop;
+  uint32_t h;
+
+#define HASHC   h = *key++ + 65599 * h
+
+  h = 0;
+  key = keyarg;
+  if (len > 0)
+    {
+      loop = (len + 8 - 1) >> 3;
+      switch (len & (8 - 1))
+        {
+        case 0:
+          do
+            {
+              HASHC;
+              /* FALLTHROUGH */
+            case 7:
+              HASHC;
+              /* FALLTHROUGH */
+            case 6:
+              HASHC;
+              /* FALLTHROUGH */
+            case 5:
+              HASHC;
+              /* FALLTHROUGH */
+            case 4:
+              HASHC;
+              /* FALLTHROUGH */
+            case 3:
+              HASHC;
+              /* FALLTHROUGH */
+            case 2:
+              HASHC;
+              /* FALLTHROUGH */
+            case 1:
+              HASHC;
+            }
+	  while (--loop);
+        }
+    }
+  return h;
+}
+
+libc_hidden_def (__nss_hash)