Add new cupsdUnlinkOrRemoveFile function and use it to avoid extraneous use of

the secure removal function.

Change from a 7-pass algorithm to a 1-pass algorithm - no current drive needs
7 passes anymore, and 7 passes causes unnecessary wear-and-tear on SSDs/flash.

git-svn-id: svn+ssh://src.apple.com/svn/cups/cups.org/trunk@10885 7a7537e8-13f0-0310-91df-b6672ffda945

diff --git a/scheduler/cupsd.h b/scheduler/cupsd.h
index c59d1272d7ed50ea96e90448f7d54ad6a1949226..ddd642b8db754bae8e354c05cf6e6ebe18b5cdf9 100644 (file)
--- a/scheduler/cupsd.h
+++ b/scheduler/cupsd.h
@@ -3,7 +3,7 @@
  *
  *   Main header file for the CUPS scheduler.
  *
- *   Copyright 2007-2012 by Apple Inc.
+ *   Copyright 2007-2013 by Apple Inc.
  *   Copyright 1997-2007 by Easy Software Products, all rights reserved.
  *
  *   These coded instructions, statements, and computer programs are the
@@ -187,6 +187,7 @@ extern cups_file_t  *cupsdCreateConfFile(const char *filename, mode_t mode);
 extern cups_file_t     *cupsdOpenConfFile(const char *filename);
 extern int             cupsdOpenPipe(int *fds);
 extern int             cupsdRemoveFile(const char *filename);
+extern int             cupsdUnlinkOrRemoveFile(const char *filename);
 
 /* main.c */
 extern int             cupsdAddString(cups_array_t **a, const char *s);

diff --git a/scheduler/file.c b/scheduler/file.c
index 8d33610c194a861ae408782e302cfe5a9c429b1e..ca5aa5e2c5284f8d191431fae6fac89b7695014c 100644 (file)
--- a/scheduler/file.c
+++ b/scheduler/file.c
@@ -3,7 +3,7 @@
  *
  *   File functions for the CUPS scheduler.
  *
- *   Copyright 2007-2011 by Apple Inc.
+ *   Copyright 2007-2013 by Apple Inc.
  *   Copyright 1997-2007 by Easy Software Products, all rights reserved.
  *
  *   These coded instructions, statements, and computer programs are the
@@ -14,15 +14,17 @@
  *
  * Contents:
  *
- *   cupsdCleanFiles()           - Clean out old files.
+ *   cupsdCleanFiles()          - Clean out old files.
  *   cupsdCloseCreatedConfFile() - Close a created configuration file and move
- *                                 into place.
- *   cupsdClosePipe()            - Close a pipe as necessary.
- *   cupsdCreateConfFile()       - Create a configuration file safely.
- *   cupsdOpenConfFile()         - Open a configuration file.
- *   cupsdOpenPipe()             - Create a pipe which is closed on exec.
- *   cupsdRemoveFile()           - Remove a file using the 7-pass US DoD method.
- *   overwrite_data()            - Overwrite the data in a file.
+ *                                into place.
+ *   cupsdClosePipe()           - Close a pipe as necessary.
+ *   cupsdCreateConfFile()      - Create a configuration file safely.
+ *   cupsdOpenConfFile()        - Open a configuration file.
+ *   cupsdOpenPipe()            - Create a pipe which is closed on exec.
+ *   cupsdRemoveFile()          - Remove a file securely.
+ *   cupsdUnlinkOrRemoveFile()  - Unlink or securely remove a file depending
+ *                                on the configuration.
+ *   overwrite_data()           - Overwrite the data in a file.
  */
 
 /*
@@ -43,7 +45,7 @@ static int    overwrite_data(int fd, const char *buffer, int bufsize,
 /*
  * 'cupsdCleanFiles()' - Clean out old files.
  */
- 
+
 void
 cupsdCleanFiles(const char *path,      /* I - Directory to clean */
                 const char *pattern)   /* I - Filename pattern or NULL */
@@ -65,7 +67,7 @@ cupsdCleanFiles(const char *path,     /* I - Directory to clean */
     return;
   }
 
-  cupsdLogMessage(CUPSD_LOG_INFO, "Cleaning out old files in \"%s\"...", path);
+  cupsdLogMessage(CUPSD_LOG_INFO, "Cleaning out old files in \"%s\".", path);
 
   while ((dent = cupsDirRead(dir)) != NULL)
   {
@@ -81,13 +83,11 @@ cupsdCleanFiles(const char *path,   /* I - Directory to clean */
       status = rmdir(filename);
     }
     else
-      status = unlink(filename);
+      status = cupsdUnlinkOrRemoveFile(filename);
 
     if (status)
       cupsdLogMessage(CUPSD_LOG_ERROR, "Unable to remove \"%s\" - %s", filename,
                      strerror(errno));
-    else
-      cupsdLogMessage(CUPSD_LOG_DEBUG, "Removed \"%s\"...", filename);
   }
 
   cupsDirClose(dir);
@@ -123,7 +123,7 @@ cupsdCloseCreatedConfFile(
   snprintf(newfile, sizeof(newfile), "%s.N", filename);
   snprintf(oldfile, sizeof(oldfile), "%s.O", filename);
 
-  if ((cupsdRemoveFile(oldfile) && errno != ENOENT) ||
+  if ((cupsdUnlinkOrRemoveFile(oldfile) && errno != ENOENT) ||
       (rename(filename, oldfile) && errno != ENOENT) ||
       rename(newfile, filename))
   {
@@ -285,14 +285,27 @@ cupsdOpenPipe(int *fds)                   /* O - Pipe file descriptors (2) */
 
 
 /*
- * 'cupsdRemoveFile()' - Remove a file using the 7-pass US DoD method.
+ * 'cupsdRemoveFile()' - Remove a file securely.
  */
 
 int                                    /* O - 0 on success, -1 on error */
 cupsdRemoveFile(const char *filename)  /* I - File to remove */
 {
 #ifdef HAVE_REMOVEFILE
-  return (removefile(filename, NULL, REMOVEFILE_SECURE_7_PASS));
+ /*
+  * See if the file exists...
+  */
+
+  if (access(filename, 0))
+    return (0);
+
+  cupsdLogMessage(CUPSD_LOG_DEBUG, "Securely removing \"%s\".", filename);
+
+ /*
+  * Remove the file...
+  */
+
+  return (removefile(filename, NULL, REMOVEFILE_SECURE_1_PASS));
 
 #else
   int                  fd;             /* File descriptor */
@@ -301,6 +314,15 @@ cupsdRemoveFile(const char *filename)      /* I - File to remove */
   int                  i;              /* Looping var */
 
 
+ /*
+  * See if the file exists...
+  */
+
+  if (access(filename, 0))
+    return (0);
+
+  cupsdLogMessage(CUPSD_LOG_DEBUG, "Securely removing \"%s\".", filename);
+
  /*
   * First open the file for writing in exclusive mode.
   */
@@ -330,31 +352,9 @@ cupsdRemoveFile(const char *filename)      /* I - File to remove */
   }
 
  /*
-  * Overwrite the file 7 times with 0xF6, 0x00, 0xFF, random, 0x00, 0xFF,
-  * and more random data.
+  * Overwrite the file with random data.
   */
 
-  memset(buffer, 0xF6, sizeof(buffer));
-  if (overwrite_data(fd, buffer, sizeof(buffer), (int)info.st_size))
-  {
-    close(fd);
-    return (-1);
-  }
-
-  memset(buffer, 0x00, sizeof(buffer));
-  if (overwrite_data(fd, buffer, sizeof(buffer), (int)info.st_size))
-  {
-    close(fd);
-    return (-1);
-  }
-
-  memset(buffer, 0xFF, sizeof(buffer));
-  if (overwrite_data(fd, buffer, sizeof(buffer), (int)info.st_size))
-  {
-    close(fd);
-    return (-1);
-  }
-
   CUPS_SRAND(time(NULL));
 
   for (i = 0; i < sizeof(buffer); i ++)
@@ -365,39 +365,31 @@ cupsdRemoveFile(const char *filename)     /* I - File to remove */
     return (-1);
   }
 
-  memset(buffer, 0x00, sizeof(buffer));
-  if (overwrite_data(fd, buffer, sizeof(buffer), (int)info.st_size))
-  {
-    close(fd);
-    return (-1);
-  }
-
-  memset(buffer, 0xFF, sizeof(buffer));
-  if (overwrite_data(fd, buffer, sizeof(buffer), (int)info.st_size))
-  {
-    close(fd);
-    return (-1);
-  }
-
-  for (i = 0; i < sizeof(buffer); i ++)
-    buffer[i] = CUPS_RAND();
-  if (overwrite_data(fd, buffer, sizeof(buffer), (int)info.st_size))
-  {
-    close(fd);
-    return (-1);
-  }
-
  /*
-  * Whew!  Close the file (which will lead to the actual deletion) and
-  * return success...
+  * Close the file, which will lead to the actual deletion, and return...
   */
 
-  close(fd);
-  return (0);
+  return (close(fd));
 #endif /* HAVE_REMOVEFILE */
 }
 
 
+/*
+ * 'cupsdUnlinkOrRemoveFile()' - Unlink or securely remove a file depending
+ *                               on the configuration.
+ */
+
+int                                    /* O - 0 on success, -1 on error */
+cupsdUnlinkOrRemoveFile(
+    const char *filename)              /* I - Filename */
+{
+  if (Classification)
+    return (cupsdRemoveFile(filename));
+  else
+    return (unlink(filename));
+}
+
+
 #ifndef HAVE_REMOVEFILE
 /*
  * 'overwrite_data()' - Overwrite the data in a file.

diff --git a/scheduler/job.c b/scheduler/job.c
index ffe72a56ef3b3cafa2e9b79e5c58b00d9b7a3176..85e0756486855c9773e13746803771753ae079e2 100644 (file)
--- a/scheduler/job.c
+++ b/scheduler/job.c
@@ -4326,10 +4326,7 @@ remove_job_files(cupsd_job_t *job)       /* I - Job */
   {
     snprintf(filename, sizeof(filename), "%s/d%05d-%03d", RequestRoot,
             job->id, i);
-    if (Classification)
-      cupsdRemoveFile(filename);
-    else
-      unlink(filename);
+    cupsdUnlinkOrRemoveFile(filename);
   }
 
   free(job->filetypes);
@@ -4360,10 +4357,7 @@ remove_job_history(cupsd_job_t *job)     /* I - Job */
 
   snprintf(filename, sizeof(filename), "%s/c%05d", RequestRoot,
           job->id);
-  if (Classification)
-    cupsdRemoveFile(filename);
-  else
-    unlink(filename);
+  cupsdUnlinkOrRemoveFile(filename);
 
   LastEvent |= CUPSD_EVENT_PRINTER_STATE_CHANGED;
 }