[Findutils-patches] [PATCH 1/2] find: add SELinux support

[James Youngman]

From: Kamil Dudka <address@hidden>

* find/defs.h: Add SELinux related definitions.
* find/tree.c: Add -context predicate to lookup.
* find/pred.c: Handle %Z printf directive.
* find/parser.c: Parse -context predicate and %Z printf directive.
* find/find.1: Mention -context predicate and %Z printf directive.
* doc/find.texi: Mention -context predicate and %Z printf directive.
* find/Makefile.am: Add SELinux libraries.
* import-gnulib.config: Require gnulib module selinux-h.
---
 ChangeLog            |   12 +++++
 NEWS                 |    4 ++
 doc/find.texi        |   17 +++++++
 find/Makefile.am     |    2 +-
 find/defs.h          |    6 +++
 find/find.1          |    4 ++
 find/parser.c        |  123 +++++++++++++++++++++++++++++++++++++++++++++++++-
 find/pred.c          |   38 +++++++++++++++
 find/tree.c          |    2 +
 import-gnulib.config |    1 +
 10 files changed, 206 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 558f023..0d990f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2009-07-11  Kamil Dudka  <address@hidden>
+
+       find: add SELinux support
+       * find/defs.h: Add SELinux related definitions.
+       * find/tree.c: Add -context predicate to lookup.
+       * find/pred.c: Handle %Z printf directive.
+       * find/parser.c: Parse -context predicate and %Z printf directive.
+       * find/find.1: Mention -context predicate and %Z printf directive.
+       * doc/find.texi: Mention -context predicate and %Z printf directive.
+       * find/Makefile.am: Add SELinux libraries.
+       * import-gnulib.config: Require gnulib module selinux-h.
+
 2009-06-11  James Youngman  <address@hidden>
 
        Make import-gnulib.sh faster in the common case where neither
diff --git a/NEWS b/NEWS
index cc5fbc0..0675bb2 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,10 @@ GNU findutils NEWS - User visible changes.     -*- outline -*- 
(allout)
 
 * Major changes in release 4.5.6, YYYY-MM-DD
 
+** Functional Enhancements to find
+
+patch #4848: Patch - Support for SELinux
+
 ** Bug Fixes
 
 #24873: Duplicate fprint option corrupts output
diff --git a/doc/find.texi b/doc/find.texi
index 6a11564..9fa207a 100644
--- a/doc/find.texi
+++ b/doc/find.texi
@@ -1242,6 +1242,14 @@ situation.
 
 @end deffn
 
address@hidden Test -context pattern
+True if file's SELinux context matches the pattern @var{pattern}.
+The pattern uses shell glob matching.
+
+This predicate is supported only on @code{find} versions compiled with
+SELinux support and only when SELinux is enabled.
address@hidden deffn
+
 @node Contents
 @section Contents
 
@@ -1733,6 +1741,7 @@ from the novel you are reading.
 * Size Directives::
 * Location Directives::
 * Time Directives::
+* Other Directives::
 * Formatting Flags::
 @end menu
 
@@ -1890,6 +1899,14 @@ File's last modification time in the format specified by 
@var{k}
 (@pxref{Time Formats}).
 @end table
 
address@hidden Other Directives
address@hidden Other Directives
+
address@hidden @code
address@hidden %Z
+File's SELinux context, or empty string if the file has no SELinux context.
address@hidden table
+
 @node Time Formats
 @subsection Time Formats
 
diff --git a/find/Makefile.am b/find/Makefile.am
index 91dba85..c0a4164 100644
--- a/find/Makefile.am
+++ b/find/Makefile.am
@@ -27,7 +27,7 @@ endif
 
 EXTRA_DIST = defs.h sharefile.h $(man_MANS)
 INCLUDES = -I../gnulib/lib -I$(top_srcdir)/lib -I$(top_srcdir)/gnulib/lib 
-I../intl -DLOCALEDIR=\"$(localedir)\"
-LDADD = ./libfindtools.a ../lib/libfind.a ../gnulib/lib/libgnulib.a $(LIBINTL) 
$(LIB_CLOCK_GETTIME) $(LIB_CLOSE) @FINDLIBS@
+LDADD = ./libfindtools.a ../lib/libfind.a ../gnulib/lib/libgnulib.a $(LIBINTL) 
$(LIB_CLOCK_GETTIME) $(LIB_CLOSE) @FINDLIBS@ @LIB_SELINUX@
 man_MANS = find.1
 SUBDIRS = . testsuite
 
diff --git a/find/defs.h b/find/defs.h
index 692328a..c5a491a 100644
--- a/find/defs.h
+++ b/find/defs.h
@@ -48,6 +48,7 @@ Please stop compiling the program now
 #include <stdbool.h>           /* for bool/boolean */
 #include <stdint.h>            /* for uintmax_t */
 #include <sys/stat.h> /* S_ISUID etc. */
+#include <selinux/selinux.h>
 
 
 
@@ -319,6 +320,7 @@ struct predicate
     struct samefile_file_id samefileid; /* samefile */
     mode_t type;               /* type */
     struct format_val printf_vec; /* printf fprintf fprint ls fls print0 
fprint0 print */
+    security_context_t scontext; /* security context */
   } args;
 
   /* The next predicate in the user input sequence,
@@ -463,6 +465,7 @@ PREDICATEFUNCTION pred_used;
 PREDICATEFUNCTION pred_user;
 PREDICATEFUNCTION pred_writable;
 PREDICATEFUNCTION pred_xtype;
+PREDICATEFUNCTION pred_context;
 
 
 
@@ -605,6 +608,9 @@ struct options
    */
   int regex_options;
 
+  /* function used to get file context */
+  int (*x_getfilecon) ();
+
   /* Optimisation level.  One is the default.
    */
   unsigned short optimisation_level;
diff --git a/find/find.1 b/find/find.1
index e2c1aaa..e48f655 100644
--- a/find/find.1
+++ b/find/find.1
@@ -930,6 +930,8 @@ if \fIc\fR is `l'.  In other words, for symbolic links,
 checks the type of the file that
 .B \-type
 does not check.
+.IP "\-context \fIpattern\fR"
+(SELinux only) Security context of the file matches glob \fIpattern\fR.
 
 .SS ACTIONS
 .IP "\-delete\fR"
@@ -1351,6 +1353,8 @@ File's type (like in
 U=unknown type (shouldn't happen)
 .IP %Y
 File's type (like %y), plus follow symlinks: L=loop, N=nonexistent
+.IP %Z
+(SELinux only) file's security context.
 .PP
 A `%' character followed by any other character is discarded, but the
 other character is printed (don't rely on this, as further format
diff --git a/find/parser.c b/find/parser.c
index 427c14a..179061a 100644
--- a/find/parser.c
+++ b/find/parser.c
@@ -53,6 +53,8 @@
 #include <unistd.h>
 #include <sys/stat.h>
 
+#include <selinux/selinux.h>
+
 #if ENABLE_NLS
 # include <libintl.h>
 # define _(Text) gettext (Text)
@@ -155,6 +157,7 @@ static boolean parse_noignore_race PARAMS((const struct 
parser_table*, char *arg
 static boolean parse_warn          PARAMS((const struct parser_table*, char 
*argv[], int *arg_ptr));
 static boolean parse_xtype         PARAMS((const struct parser_table*, char 
*argv[], int *arg_ptr));
 static boolean parse_quit          PARAMS((const struct parser_table*, char 
*argv[], int *arg_ptr));
+static boolean parse_context       PARAMS((const struct parser_table*, char 
*argv[], int *arg_ptr));
 
 boolean parse_print             PARAMS((const struct parser_table*, char 
*argv[], int *arg_ptr));
 
@@ -251,6 +254,7 @@ static struct parser_table const parse_table[] =
   PARSE_TEST       ("cmin",                  cmin),         /* GNU */
   PARSE_TEST       ("cnewer",                cnewer),       /* GNU */
   {ARG_TEST,       "ctime",                  parse_time, pred_ctime}, /* POSIX 
*/
+  PARSE_TEST       ("context",               context),      /* GNU */
   PARSE_POSOPT     ("daystart",              daystart),             /* GNU */
   PARSE_ACTION     ("delete",                delete), /* GNU, Mac OS, FreeBSD 
*/
   PARSE_OPTION     ("d",                     d), /* Mac OS X, FreeBSD, NetBSD, 
OpenBSD, but deprecated  in favour of -depth */
@@ -347,6 +351,85 @@ static struct parser_table const parse_table[] =
 static const char *first_nonoption_arg = NULL;
 static const struct parser_table *noop = NULL;
 
+static int
+fallback_getfilecon (const char *name, security_context_t *p, int prev_rv)
+{
+  /* Our original getfilecon () call failed.  Perhaps we can't follow a
+   * symbolic link.  If that might be the problem, lgetfilecon () the link.
+   * Otherwise, admit defeat. */
+  switch (errno)
+    {
+      case ENOENT:
+      case ENOTDIR:
+#ifdef DEBUG_STAT
+       fprintf (stderr, "fallback_getfilecon(): getfilecon(%s) failed; falling 
"
+                       "back on lgetfilecon()\n", name);
+#endif
+       return lgetfilecon (name, p);
+
+      case EACCES:
+      case EIO:
+      case ELOOP:
+      case ENAMETOOLONG:
+#ifdef EOVERFLOW
+      case EOVERFLOW:        /* EOVERFLOW is not #defined on UNICOS. */
+#endif
+      default:
+       return prev_rv;
+    }
+}
+
+/* optionh_getfilecon () implements the getfilecon operation when the
+ * -H option is in effect.
+ *
+ * If the item to be examined is a command-line argument, we follow
+ * symbolic links.  If the getfilecon () call fails on the command-line
+ * item, we fall back on the properties of the symbolic link.
+ *
+ * If the item to be examined is not a command-line argument, we
+ * examine the link itself. */
+int
+optionh_getfilecon (const char *name, security_context_t *p)
+{
+  int rv;
+  if (0 == state.curdepth)
+    {
+      /* This file is from the command line; dereference the link (if it is
+        a link). */
+      rv = getfilecon (name, p);
+      if (0 == rv)
+       return 0;               /* success */
+      else
+       return fallback_getfilecon (name, p, rv);
+    }
+  else
+    {
+      /* Not a file on the command line; do not dereference the link. */
+      return lgetfilecon (name, p);
+    }
+}
+
+/* optionl_getfilecon () implements the getfilecon operation when the
+ * -L option is in effect.  That option makes us examine the thing the
+ * symbolic link points to, not the symbolic link itself. */
+int
+optionl_getfilecon (const char *name, security_context_t *p)
+{
+  int rv = getfilecon (name, p);
+  if (0 == rv)
+    return 0;                  /* normal case. */
+  else
+    return fallback_getfilecon (name, p, rv);
+}
+
+/* optionp_getfilecon () implements the stat operation when the -P
+ * option is in effect (this is also the default).  That option makes
+ * us examine the symbolic link itself, not the thing it points to. */
+int
+optionp_getfilecon (const char *name, security_context_t *p)
+{
+  return lgetfilecon (name, p);
+}
 
 void
 check_option_combinations(const struct predicate *p)
@@ -450,11 +533,13 @@ set_follow_state(enum SymlinkOption opt)
        {
        case SYMLINK_ALWAYS_DEREF:  /* -L */
          options.xstat = optionl_stat;
+         options.x_getfilecon = optionl_getfilecon;
          options.no_leaf_check = true;
          break;
 
        case SYMLINK_NEVER_DEREF:       /* -P (default) */
          options.xstat = optionp_stat;
+         options.x_getfilecon = optionp_getfilecon;
          /* Can't turn no_leaf_check off because the user might have specified
           * -noleaf anyway
           */
@@ -462,6 +547,7 @@ set_follow_state(enum SymlinkOption opt)
 
        case SYMLINK_DEREF_ARGSONLY: /* -H */
          options.xstat = optionh_stat;
+         options.x_getfilecon = optionh_getfilecon;
          options.no_leaf_check = true;
        }
     }
@@ -1127,8 +1213,10 @@ tests (N can be +N or -N or N): -amin N -anewer FILE 
-atime N -cmin N\n\
       -nouser -nogroup -path PATTERN -perm [+-]MODE -regex PATTERN\n\
       -readable -writable -executable\n\
       -wholename PATTERN -size N[bcwkMG] -true -type [bcdpflsD] -uid N\n\
-      -used N -user NAME -xtype [bcdpfls]\n"));
+      -used N -user NAME -xtype [bcdpfls]"));
   puts (_("\
+      -context CONTEXT\n"));
+  puts (_("\n\
 actions: -delete -print0 -printf FORMAT -fprintf FILE FORMAT -print \n\
       -fprint0 FILE -fprint FILE -ls -fls FILE -prune -quit\n\
       -exec COMMAND ; -exec COMMAND {} + -ok COMMAND ;\n\
@@ -2523,6 +2611,11 @@ parse_version (const struct parser_table* entry, char 
**argv, int *arg_ptr)
   printf("LEAF_OPTIMISATION ");
   ++features;
 #endif
+  if (0 < is_selinux_enabled ())
+    {
+      printf ("SELINUX ");
+      ++features;
+    }
 
   flags = 0;
   if (is_fts_enabled(&flags))
@@ -2558,6 +2651,31 @@ parse_version (const struct parser_table* entry, char 
**argv, int *arg_ptr)
 }
 
 static boolean
+parse_context (const struct parser_table* entry, char **argv, int *arg_ptr)
+{
+  struct predicate *our_pred;
+
+  if ((argv == NULL) || (argv[*arg_ptr] == NULL))
+    return false;
+
+  if (is_selinux_enabled () <= 0)
+    {
+      error (1, 0, _("invalid predicate -context: SELinux is not enabled."));
+      return false;
+    }
+  our_pred = insert_primary (entry);
+  our_pred->est_success_rate = 0.01f;
+  our_pred->need_stat = false;
+#ifdef DEBUG
+  our_pred->p_name = find_pred_name (pred_context);
+#endif /*DEBUG*/
+  our_pred->args.scontext = argv[*arg_ptr];
+
+  (*arg_ptr)++;
+  return true;
+}
+
+static boolean
 parse_xdev (const struct parser_table* entry, char **argv, int *arg_ptr)
 {
   options.stay_on_filesystem = true;
@@ -2808,7 +2926,7 @@ insert_fprintf (struct format_val *vec,
          if (*scan2 == '.')
            for (scan2++; ISDIGIT (*scan2); scan2++)
              /* Do nothing. */ ;
-         if (strchr ("abcdDfFgGhHiklmMnpPsStuUyY", *scan2))
+         if (strchr ("abcdDfFgGhHiklmMnpPsStuUyYZ", *scan2))
            {
              segmentp = make_segment (segmentp, format, scan2 - format,
                                       KIND_FORMAT, *scan2, 0,
@@ -2940,6 +3058,7 @@ make_segment (struct segment **segment,
     case 'h':                  /* leading directories part of path */
     case 'p':                  /* pathname */
     case 'P':                  /* pathname with ARGV element stripped */
+    case 'Z':                  /* SELinux security context */
       *fmt++ = 's';
       break;
 
diff --git a/find/pred.c b/find/pred.c
index 1b95959..3e95bf2 100644
--- a/find/pred.c
+++ b/find/pred.c
@@ -47,6 +47,8 @@
 #include "error.h"
 #include "verify.h"
 
+#include <selinux/selinux.h>
+
 #if ENABLE_NLS
 # include <libintl.h>
 # define _(Text) gettext (Text)
@@ -230,6 +232,7 @@ struct pred_assoc pred_table[] =
   {pred_user, "user    "},
   {pred_writable, "writable "},
   {pred_xtype, "xtype   "},
+  {pred_context, "context"},
   {0, "none    "}
 };
 #endif
@@ -1054,6 +1057,22 @@ do_fprintf(struct format_val *dest,
                             mode_to_filetype(stat_buf->st_mode & S_IFMT));
          }
          break;
+       case 'Z':               /* SELinux security context */
+         {
+           security_context_t scontext;
+           int rv = (*options.x_getfilecon) (state.rel_pathname, &scontext);
+           if (rv < 0)
+             {
+               error (0, errno, "getfilecon: %s",
+                   safely_quote_err_filename (0, pathname));
+             }
+           else
+             {
+               checked_fprintf (dest, segment->text, scontext);
+               freecon (scontext);
+             }
+         }
+         break;
        }
       /* end of KIND_FORMAT case */
       break;
@@ -1866,6 +1885,25 @@ pred_xtype (const char *pathname, struct stat *stat_buf, 
struct predicate *pred_
    */
   return (pred_type (pathname, &sbuf, pred_ptr));
 }
+
+
+boolean
+pred_context (const char *pathname, struct stat *stat_buf,
+             struct predicate *pred_ptr)
+{
+  security_context_t scontext;
+  int rv = (*options.x_getfilecon) (state.rel_pathname, &scontext);
+  if (rv < 0)
+    {
+      error (0, errno, "getfilecon: %s", safely_quote_err_filename (0, 
pathname));
+      return false;
+    }
+
+  rv = (fnmatch (pred_ptr->args.scontext, scontext, 0) == 0);
+  freecon (scontext);
+  return rv;
+}
+
 
 /*  1) fork to get a child; parent remembers the child pid
     2) child execs the command requested
diff --git a/find/tree.c b/find/tree.c
index 929c5f6..8ab1527 100644
--- a/find/tree.c
+++ b/find/tree.c
@@ -906,6 +906,7 @@ static struct pred_cost_lookup costlookup[] =
     { pred_cmin      ,  NeedsStatInfo,       },
     { pred_cnewer    ,  NeedsStatInfo,       },
     { pred_comma     ,  NeedsNothing,        },
+    { pred_context   ,  NeedsAccessInfo      },
     { pred_ctime     ,  NeedsStatInfo,       },
     { pred_delete    ,  NeedsSyncDiskHit     },
     { pred_empty     ,  NeedsStatInfo        },
@@ -1441,6 +1442,7 @@ get_new_pred (const struct parser_table *entry)
   last_pred->need_type = true;
   last_pred->need_inum = false;
   last_pred->args.str = NULL;
+  last_pred->args.scontext = NULL;
   last_pred->pred_next = NULL;
   last_pred->pred_left = NULL;
   last_pred->pred_right = NULL;
diff --git a/import-gnulib.config b/import-gnulib.config
index 1d7a43b..cbb384e 100644
--- a/import-gnulib.config
+++ b/import-gnulib.config
@@ -65,6 +65,7 @@ realloc
 regex
 rpmatch
 savedir
+selinux-h
 stat-macros
 stat-time
 stdint
-- 
1.5.6.5