* nis/nss_nis/nis-service.c (_nss_nis_getservbyname_r): Correct

	computation of keylen.

1 files changed, 473 insertions, 0 deletions

diff --git a/nscd/servicescache.c b/nscd/servicescache.c
new file mode 100644
index 0000000000..ea4fa35100
--- /dev/null
+++ b/nscd/servicescache.c
@@ -0,0 +1,473 @@
+/* Cache handling for services lookup.
+   Copyright (C) 2007 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@drepper.com>, 2007.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License version 2 as
+   published by the Free Software Foundation.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#include <alloca.h>
+#include <assert.h>
+#include <errno.h>
+#include <libintl.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include "nscd.h"
+#include "dbg_log.h"
+
+
+/* This is the standard reply in case the service is disabled.  */
+static const serv_response_header disabled =
+{
+  .version = NSCD_VERSION,
+  .found = -1,
+  .s_name_len = 0,
+  .s_proto_len = 0,
+  .s_aliases_cnt = 0,
+  .s_port = -1
+};
+
+/* This is the struct describing how to write this record.  */
+const struct iovec serv_iov_disabled =
+{
+  .iov_base = (void *) &disabled,
+  .iov_len = sizeof (disabled)
+};
+
+
+/* This is the standard reply in case we haven't found the dataset.  */
+static const serv_response_header notfound =
+{
+  .version = NSCD_VERSION,
+  .found = 0,
+  .s_name_len = 0,
+  .s_proto_len = 0,
+  .s_aliases_cnt = 0,
+  .s_port = -1
+};
+
+
+static void
+cache_addserv (struct database_dyn *db, int fd, request_header *req,
+	       const void *key, struct servent *serv, uid_t owner,
+	       struct hashentry *he, struct datahead *dh, int errval)
+{
+  ssize_t total;
+  ssize_t written;
+  time_t t = time (NULL);
+
+  /* We allocate all data in one memory block: the iov vector,
+     the response header and the dataset itself.  */
+  struct dataset
+  {
+    struct datahead head;
+    serv_response_header resp;
+    char strdata[0];
+  } *dataset;
+
+  assert (offsetof (struct dataset, resp) == offsetof (struct datahead, data));
+
+  if (serv == NULL)
+    {
+      if (he != NULL && errval == EAGAIN)
+	{
+	  /* If we have an old record available but cannot find one
+	     now because the service is not available we keep the old
+	     record and make sure it does not get removed.  */
+	  if (reload_count != UINT_MAX)
+	    /* Do not reset the value if we never not reload the record.  */
+	    dh->nreloads = reload_count - 1;
+
+	  written = total = 0;
+	}
+      else
+	{
+	  /* We have no data.  This means we send the standard reply for this
+	     case.  */
+	  total = sizeof (notfound);
+
+	  written = TEMP_FAILURE_RETRY (send (fd, &notfound, total,
+					      MSG_NOSIGNAL));
+
+	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+	  /* If we cannot permanently store the result, so be it.  */
+	  if (dataset != NULL)
+	    {
+	      dataset->head.allocsize = sizeof (struct dataset) + req->key_len;
+	      dataset->head.recsize = total;
+	      dataset->head.notfound = true;
+	      dataset->head.nreloads = 0;
+	      dataset->head.usable = true;
+
+	      /* Compute the timeout time.  */
+	      dataset->head.timeout = t + db->negtimeout;
+
+	      /* This is the reply.  */
+	      memcpy (&dataset->resp, &notfound, total);
+
+	      /* Copy the key data.  */
+	      memcpy (dataset->strdata, key, req->key_len);
+
+	      /* If necessary, we also propagate the data to disk.  */
+	      if (db->persistent)
+		{
+		  // XXX async OK?
+		  uintptr_t pval = (uintptr_t) dataset & ~pagesize_m1;
+		  msync ((void *) pval,
+			 ((uintptr_t) dataset & pagesize_m1)
+			 + sizeof (struct dataset) + req->key_len, MS_ASYNC);
+		}
+
+	      /* Now get the lock to safely insert the records.  */
+	      pthread_rwlock_rdlock (&db->lock);
+
+	      if (cache_add (req->type, &dataset->strdata, req->key_len,
+			     &dataset->head, true, db, owner) < 0)
+		/* Ensure the data can be recovered.  */
+		dataset->head.usable = false;
+
+	      pthread_rwlock_unlock (&db->lock);
+
+	      /* Mark the old entry as obsolete.  */
+	      if (dh != NULL)
+		dh->usable = false;
+	    }
+	  else
+	    ++db->head->addfailed;
+	}
+    }
+  else
+    {
+      /* Determine the I/O structure.  */
+      size_t s_name_len = strlen (serv->s_name) + 1;
+      size_t s_proto_len = strlen (serv->s_proto) + 1;
+      uint32_t *s_aliases_len;
+      size_t s_aliases_cnt;
+      char *aliases;
+      char *cp;
+      size_t cnt;
+
+      /* Determine the number of aliases.  */
+      s_aliases_cnt = 0;
+      for (cnt = 0; serv->s_aliases[cnt] != NULL; ++cnt)
+	++s_aliases_cnt;
+      /* Determine the length of all aliases.  */
+      s_aliases_len = (uint32_t *) alloca (s_aliases_cnt * sizeof (uint32_t));
+      total = 0;
+      for (cnt = 0; cnt < s_aliases_cnt; ++cnt)
+	{
+	  s_aliases_len[cnt] = strlen (serv->s_aliases[cnt]) + 1;
+	  total += s_aliases_len[cnt];
+	}
+
+      total += (sizeof (struct dataset)
+		+ s_name_len
+		+ s_proto_len
+		+ s_aliases_cnt * sizeof (uint32_t));
+      written = total;
+
+      /* If we refill the cache, first assume the reconrd did not
+	 change.  Allocate memory on the cache since it is likely
+	 discarded anyway.  If it turns out to be necessary to have a
+	 new record we can still allocate real memory.  */
+      bool alloca_used = false;
+      dataset = NULL;
+
+      if (he == NULL)
+	{
+	  dataset = (struct dataset *) mempool_alloc (db,
+						      total + req->key_len);
+	  if (dataset == NULL)
+	    ++db->head->addfailed;
+	}
+
+      if (dataset == NULL)
+	{
+	  /* We cannot permanently add the result in the moment.  But
+	     we can provide the result as is.  Store the data in some
+	     temporary memory.  */
+	  dataset = (struct dataset *) alloca (total + req->key_len);
+
+	  /* We cannot add this record to the permanent database.  */
+	  alloca_used = true;
+	}
+
+      dataset->head.allocsize = total + req->key_len;
+      dataset->head.recsize = total - offsetof (struct dataset, resp);
+      dataset->head.notfound = false;
+      dataset->head.nreloads = he == NULL ? 0 : (dh->nreloads + 1);
+      dataset->head.usable = true;
+
+      /* Compute the timeout time.  */
+      dataset->head.timeout = t + db->postimeout;
+
+      dataset->resp.version = NSCD_VERSION;
+      dataset->resp.found = 1;
+      dataset->resp.s_name_len = s_name_len;
+      dataset->resp.s_proto_len = s_proto_len;
+      dataset->resp.s_port = serv->s_port;
+      dataset->resp.s_aliases_cnt = s_aliases_cnt;
+
+      cp = dataset->strdata;
+
+      cp = mempcpy (cp, serv->s_name, s_name_len);
+      cp = mempcpy (cp, serv->s_proto, s_proto_len);
+      cp = mempcpy (cp, s_aliases_len, s_aliases_cnt * sizeof (uint32_t));
+
+      /* Then the aliases.  */
+      aliases = cp;
+      for (cnt = 0; cnt < s_aliases_cnt; ++cnt)
+	cp = mempcpy (cp, serv->s_aliases[cnt], s_aliases_len[cnt]);
+
+      assert (cp
+	      == dataset->strdata + total - offsetof (struct dataset,
+						      strdata));
+
+      char *key_copy = memcpy (cp, key, req->key_len);
+
+      /* Now we can determine whether on refill we have to create a new
+	 record or not.  */
+      if (he != NULL)
+	{
+	  assert (fd == -1);
+
+	  if (total + req->key_len == dh->allocsize
+	      && total - offsetof (struct dataset, resp) == dh->recsize
+	      && memcmp (&dataset->resp, dh->data,
+			 dh->allocsize - offsetof (struct dataset, resp)) == 0)
+	    {
+	      /* The data has not changed.  We will just bump the
+		 timeout value.  Note that the new record has been
+		 allocated on the stack and need not be freed.  */
+	      dh->timeout = dataset->head.timeout;
+	      ++dh->nreloads;
+	    }
+	  else
+	    {
+	      /* We have to create a new record.  Just allocate
+		 appropriate memory and copy it.  */
+	      struct dataset *newp
+		= (struct dataset *) mempool_alloc (db, total + req->key_len);
+	      if (newp != NULL)
+		{
+		  /* Adjust pointers into the memory block.  */
+		  aliases = (char *) newp + (aliases - (char *) dataset);
+		  if (key_copy != NULL)
+		    key_copy = (char *) newp + (key_copy - (char *) dataset);
+
+		  dataset = memcpy (newp, dataset, total + req->key_len);
+		  alloca_used = false;
+		}
+
+	      /* Mark the old record as obsolete.  */
+	      dh->usable = false;
+	    }
+	}
+      else
+	{
+	  /* We write the dataset before inserting it to the database
+	     since while inserting this thread might block and so would
+	     unnecessarily keep the receiver waiting.  */
+	  assert (fd != -1);
+
+#ifdef HAVE_SENDFILE
+	  if (__builtin_expect (db->mmap_used, 1) && !alloca_used)
+	    {
+	      assert (db->wr_fd != -1);
+	      assert ((char *) &dataset->resp > (char *) db->data);
+	      assert ((char *) &dataset->resp - (char *) db->head
+		      + total
+		      <= (sizeof (struct database_pers_head)
+			  + db->head->module * sizeof (ref_t)
+			  + db->head->data_size));
+	      written = sendfileall (fd, db->wr_fd,
+				     (char *) &dataset->resp
+				     - (char *) db->head, total);
+# ifndef __ASSUME_SENDFILE
+	      if (written == -1 && errno == ENOSYS)
+		goto use_write;
+# endif
+	    }
+	  else
+# ifndef __ASSUME_SENDFILE
+	  use_write:
+# endif
+#endif
+	    written = writeall (fd, &dataset->resp, total);
+	}
+
+      /* Add the record to the database.  But only if it has not been
+	 stored on the stack.  */
+      if (! alloca_used)
+	{
+	  /* If necessary, we also propagate the data to disk.  */
+	  if (db->persistent)
+	    {
+	      // XXX async OK?
+	      uintptr_t pval = (uintptr_t) dataset & ~pagesize_m1;
+	      msync ((void *) pval,
+		     ((uintptr_t) dataset & pagesize_m1)
+		     + total + req->key_len, MS_ASYNC);
+	    }
+
+	  /* Now get the lock to safely insert the records.  */
+	  pthread_rwlock_rdlock (&db->lock);
+
+	  if (cache_add (req->type, key_copy, req->key_len,
+			 &dataset->head, true, db, owner) < 0)
+	    /* Could not allocate memory.  Make sure the
+	       data gets discarded.  */
+	    dataset->head.usable = false;
+
+	  pthread_rwlock_unlock (&db->lock);
+	}
+    }
+
+  if (__builtin_expect (written != total, 0) && debug_level > 0)
+    {
+      char buf[256];
+      dbg_log (_("short write in %s: %s"),  __FUNCTION__,
+	       strerror_r (errno, buf, sizeof (buf)));
+    }
+}
+
+
+static int
+lookup (int type, char *key, struct servent *resultbufp, char *buffer,
+	size_t buflen, struct servent **serv)
+{
+  char *proto = strrchr (key, '/');
+  if (proto != NULL && proto != key)
+    {
+      key = strndupa (key, proto - key);
+      if (proto[1] == '\0')
+	proto = NULL;
+      else
+	++proto;
+    }
+
+  if (type == GETSERVBYNAME)
+    return __getservbyname_r (key, proto, resultbufp, buffer, buflen, serv);
+
+  assert (type == GETSERVBYPORT);
+  return __getservbyport_r (atol (key), proto, resultbufp, buffer, buflen,
+			    serv);
+}
+
+
+static void
+addservbyX (struct database_dyn *db, int fd, request_header *req,
+	    char *key, uid_t uid, struct hashentry *he, struct datahead *dh)
+{
+  /* Search for the entry matching the key.  Please note that we don't
+     look again in the table whether the dataset is now available.  We
+     simply insert it.  It does not matter if it is in there twice.  The
+     pruning function only will look at the timestamp.  */
+  size_t buflen = 1024;
+  char *buffer = (char *) alloca (buflen);
+  struct servent resultbuf;
+  struct servent *serv;
+  bool use_malloc = false;
+  int errval = 0;
+
+  if (__builtin_expect (debug_level > 0, 0))
+    {
+      if (he == NULL)
+	dbg_log (_("Haven't found \"%s\" in services cache!"), key);
+      else
+	dbg_log (_("Reloading \"%s\" in services cache!"), key);
+    }
+
+  while (lookup (req->type, key, &resultbuf, buffer, buflen, &serv) != 0
+	 && (errval = errno) == ERANGE)
+    {
+      errno = 0;
+
+      if (__builtin_expect (buflen > 32768, 0))
+	{
+	  char *old_buffer = buffer;
+	  buflen *= 2;
+	  buffer = (char *) realloc (use_malloc ? buffer : NULL, buflen);
+	  if (buffer == NULL)
+	    {
+	      /* We ran out of memory.  We cannot do anything but
+		 sending a negative response.  In reality this should
+		 never happen.  */
+	      serv = NULL;
+	      buffer = old_buffer;
+
+	      /* We set the error to indicate this is (possibly) a
+		 temporary error and that it does not mean the entry
+		 is not available at all.  */
+	      errval = EAGAIN;
+	      break;
+	    }
+	  use_malloc = true;
+	}
+      else
+	/* Allocate a new buffer on the stack.  If possible combine it
+	   with the previously allocated buffer.  */
+	buffer = (char *) extend_alloca (buffer, buflen, 2 * buflen);
+    }
+
+  cache_addserv (db, fd, req, key, serv, uid, he, dh, errval);
+
+  if (use_malloc)
+    free (buffer);
+}
+
+
+void
+addservbyname (struct database_dyn *db, int fd, request_header *req,
+	       void *key, uid_t uid)
+{
+  addservbyX (db, fd, req, key, uid, NULL, NULL);
+}
+
+
+void
+readdservbyname (struct database_dyn *db, struct hashentry *he,
+		 struct datahead *dh)
+{
+  request_header req =
+    {
+      .type = GETSERVBYNAME,
+      .key_len = he->len
+    };
+
+  addservbyX (db, -1, &req, db->data + he->key, he->owner, he, dh);
+}
+
+
+void
+addservbyport (struct database_dyn *db, int fd, request_header *req,
+	       void *key, uid_t uid)
+{
+  addservbyX (db, fd, req, key, uid, NULL, NULL);
+}
+
+
+void
+readdservbyport (struct database_dyn *db, struct hashentry *he,
+		 struct datahead *dh)
+{
+  request_header req =
+    {
+      .type = GETSERVBYPORT,
+      .key_len = he->len
+    };
+
+  addservbyX (db, -1, &req, db->data + he->key, he->owner, he, dh);
+}