Add fsm and rpmfi machinery for file capabilities

- new rpmfiFCaps() API to retrieve the info from rpmfi set
- fsm internals quite similar to selinux handling
- plenty of #ifdef's, another possibility would be adding cap_foo dummies to
  system.h like for selinux

lib/cpio.c

@@ -209,6 +209,7 @@ const char * cpioStrerror(int rc)
     case CPIOERR_READ_FAILED:	s = "read";	break;
     case CPIOERR_COPY_FAILED:	s = "copy";	break;
     case CPIOERR_LSETFCON_FAILED: s = "lsetfilecon";	break;
+    case CPIOERR_SETCAP_FAILED: s = "cap_set_file";	break;
 
     case CPIOERR_HDR_SIZE:	s = _("Header size too big");	break;
     case CPIOERR_UNKNOWN_FILETYPE: s = _("Unknown file type");	break;

lib/cpio.h

@@ -52,7 +52,8 @@ enum cpioErrorReturns {
 	CPIOERR_INTERNAL	= (28			),
 	CPIOERR_UNMAPPED_FILE	= (29			),
 	CPIOERR_ENOENT		= (30			),
-	CPIOERR_ENOTEMPTY	= (31			)
+	CPIOERR_ENOTEMPTY	= (31			),
+	CPIOERR_SETCAP_FAILED	= (32	| CPIOERR_CHECK_ERRNO),
 };
 
 /*

lib/fsm.c

@@ -589,6 +589,22 @@ static int fsmMapFContext(FSM_t fsm)
     return 0;
 }
 
+#if WITH_CAP
+static int fsmMapFCaps(FSM_t fsm)
+{
+    rpmts ts = fsmGetTs(fsm);
+    rpmfi fi = fsmGetFi(fsm);
+    fsm->fcaps = NULL;
+    if (ts != NULL && fi->fcaps && *fi->fcaps[fsm->ix] != '\0') {
+	cap_t fcaps = cap_from_text(fi->fcaps[fsm->ix]);
+	if (fcaps) {
+	   fsm->fcaps = fcaps;
+	}
+    } 
+    return 0;
+}
+#endif
+
 /**
  * Map next file path and action.
  * @param fsm		file state machine
@@ -1869,6 +1885,16 @@ if (!(fsm->mapFlags & CPIO_ALL_HARDLINKS)) break;
 		    rc = fsmNext(fsm, FSM_UTIME);
 		    st->st_mtime = mtime;
 		}
+#if WITH_CAP
+		if (!rc && !S_ISDIR(st->st_mode) && !getuid()) {
+		    rc = fsmMapFCaps(fsm);
+		    if (!rc && fsm->fcaps) {
+			rc = fsmNext(fsm, FSM_SETCAP);
+			cap_free(fsm->fcaps);
+		    }
+		    fsm->fcaps = NULL;
+		}
+#endif /* WITH_CAP */
 	    }
 	}
 
@@ -2077,6 +2103,14 @@ if (!(fsm->mapFlags & CPIO_ALL_HARDLINKS)) break;
 	    if (rc < 0)	rc = CPIOERR_UTIME_FAILED;
 	}
 	break;
+#if WITH_CAP
+    case FSM_SETCAP:
+	rc = cap_set_file(fsm->path, fsm->fcaps);
+	if (rc < 0) {
+	    rc = CPIOERR_SETCAP_FAILED;
+	}
+	break;
+#endif /* WITH_CAP */
     case FSM_SYMLINK:
 	rc = symlink(fsm->opath, fsm->path);
 	if (_fsm_debug && (stage & FSM_SYSCALL))
@@ -2357,6 +2391,7 @@ static const char * fileStageString(fileStage a) {
     case FSM_STAT:	return "stat";
     case FSM_READLINK:	return "readlink";
     case FSM_CHROOT:	return "chroot";
+    case FSM_SETCAP:	return "setcap";
 
     case FSM_NEXT:	return "next";
     case FSM_EAT:	return "eat";

lib/fsm.h

@@ -64,6 +64,7 @@ typedef enum fileStage_e {
     FSM_STAT	=  _fs(49),
     FSM_READLINK=  _fs(50),
     FSM_CHROOT	=  _fs(51),
+    FSM_SETCAP	=  _fs(52),
 
     FSM_NEXT	=  _fd(65),
     FSM_EAT	=  _fd(66),
@@ -154,6 +155,7 @@ struct fsm_s {
     const char * baseName;	/*!< File base name. */
     const char * digest;	/*!< Binary checksum (NULL disables). */
     security_context_t fcontext;/*!< File security context (NULL disables). */
+    cap_t fcaps;		/*!< File capabilities */
     pgpHashAlgo digestalgo;	/*!< File checksum algorithm */
     
     unsigned fflags;		/*!< File flags. */

lib/rpmfi.c

@@ -371,6 +371,15 @@ const char * rpmfiFGroup(rpmfi fi)
     return fgroup;
 }
 
+const char * rpmfiFCaps(rpmfi fi)
+{
+    const char *fcaps = NULL;
+    if (fi != NULL && fi->i >= 0 && fi->i < fi->fc) {
+	fcaps = fi->fcaps ? fi->fcaps[fi->i] : "";
+    }
+    return fcaps;
+}
+
 int rpmfiNext(rpmfi fi)
 {
     int i = -1;
@@ -1124,6 +1133,7 @@ fprintf(stderr, "*** fi %p\t%s[%d]\n", fi, fi->Type, fi->fc);
 	fi->flinks = _free(fi->flinks);
 	fi->flangs = _free(fi->flangs);
 	fi->digests = _free(fi->digests);
+	fi->fcaps = _free(fi->fcaps);
 
 	fi->cdict = _free(fi->cdict);
 
@@ -1261,6 +1271,8 @@ rpmfi rpmfiNew(const rpmts ts, Header h, rpmTag tagN, int scareMem)
     if (fi->fstates == NULL)
 	fi->fstates = xcalloc(fi->fc, sizeof(*fi->fstates));
 
+    _hgfi(h, RPMTAG_FILECAPS, &td, defFlags, fi->fcaps);
+
     fi->action = FA_UNKNOWN;
     fi->flags = 0;
 

lib/rpmfi.h

@@ -327,6 +327,15 @@ const char * rpmfiFUser(rpmfi fi);
  */
 const char * rpmfiFGroup(rpmfi fi);
 
+/** \ingroup rpmfi
+ * Return textual representation of current file capabilities 
+ * from file info set. See cap_from_text(3) for details.
+ * @param fi		file info set
+ * @return		file capability description, "" for no capabilities
+ * 			and NULL on invalid
+ */
+const char * rpmfiFCaps(rpmfi fi);
+
 /** \ingroup rpmfi
  * Return next file iterator index.
  * @param fi		file info set

lib/rpmfi_internal.h

@@ -61,6 +61,8 @@ struct rpmfi_s {
 
     const char ** fcontexts;	/*! FIle security contexts. */
 
+    const char ** fcaps;	/*! File capabilities (header) */
+
     const char ** cdict;	/*!< File class dictionary (header) */
     rpm_count_t ncdict;		/*!< No. of class entries. */
     const uint32_t * fcdictx;	/*!< File class dictionary index (header) */

system.h

@@ -229,6 +229,8 @@ void * _free(void * p)
 
 #if WITH_CAP
 #include <sys/capability.h>
+#else
+typedef void * cap_t;
 #endif
 
 #if WITH_ACL