X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/3903760236c30e3b5ace7a4eefac3a269d68957c..e8c3f78193f1895ea514044358b93b1add9322f3:/bsd/vfs/vfs_lookup.c

diff --git a/bsd/vfs/vfs_lookup.c b/bsd/vfs/vfs_lookup.c
index 128a8ce04..ccee2e1c5 100644
--- a/bsd/vfs/vfs_lookup.c
+++ b/bsd/vfs/vfs_lookup.c
@@ -105,8 +105,6 @@
 #define VOLFS_MIN_PATH_LEN  9
 
 
-static	void kdebug_lookup(struct vnode *dp, struct componentname *cnp);
-
 #if CONFIG_VOLFS
 static int vfs_getrealpath(const char * path, char * realpath, size_t bufsize, vfs_context_t ctx);
 #define MAX_VOLFS_RESTARTS 5
@@ -182,6 +180,7 @@ namei(struct nameidata *ndp)
 #if CONFIG_VOLFS
 	int volfs_restarts = 0;
 #endif
+	size_t bytes_copied = 0;
 
 	fdp = p->p_fd;
 
@@ -244,10 +243,10 @@ vnode_recycled:
 retry_copy:
 	if (UIO_SEG_IS_USER_SPACE(ndp->ni_segflg)) {
 		error = copyinstr(ndp->ni_dirp, cnp->cn_pnbuf,
-			    cnp->cn_pnlen, (size_t *)&ndp->ni_pathlen);
+			    cnp->cn_pnlen, &bytes_copied);
 	} else {
 		error = copystr(CAST_DOWN(void *, ndp->ni_dirp), cnp->cn_pnbuf,
-			    cnp->cn_pnlen, (size_t *)&ndp->ni_pathlen);
+			    cnp->cn_pnlen, &bytes_copied);
 	}
 	if (error == ENAMETOOLONG && !(cnp->cn_flags & HASBUF)) {
 		MALLOC_ZONE(cnp->cn_pnbuf, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
@@ -258,11 +257,14 @@ retry_copy:
 
 		cnp->cn_flags |= HASBUF;
 		cnp->cn_pnlen = MAXPATHLEN;
+		bytes_copied = 0;
 		
 		goto retry_copy;
 	}
 	if (error)
 	        goto error_out;
+	ndp->ni_pathlen = bytes_copied;
+	bytes_copied = 0;
 
 	/*
 	 * Since the name cache may contain positive entries of
@@ -366,6 +368,21 @@ retry_copy:
 	ndp->ni_vp  = NULLVP;
 
 	for (;;) {
+#if CONFIG_MACF
+		/*
+		 * Give MACF policies a chance to reject the lookup
+		 * before performing any filesystem operations.
+		 * This hook is called before resolving the path and
+		 * again each time a symlink is encountered.
+		 * NB: policies receive path information as supplied
+		 *     by the caller and thus cannot be trusted.
+		 */
+		error = mac_vnode_check_lookup_preflight(ctx, dp, cnp->cn_nameptr, cnp->cn_namelen);
+		if (error) {
+			goto error_out;
+		}
+#endif
+
 		ndp->ni_startdir = dp;
 
 		if ( (error = lookup(ndp)) ) {
@@ -458,6 +475,7 @@ namei_compound_available(vnode_t dp, struct nameidata *ndp)
 
 	return 0;
 }
+
 static int
 lookup_authorize_search(vnode_t dp, struct componentname *cnp, int dp_authorized_in_cache, vfs_context_t ctx)
 {
@@ -531,6 +549,7 @@ lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname
 {
 	vnode_t svp = NULLVP;
 	enum nsoperation nsop;
+	int nsflags;
 	int error;
 
 	if (dp->v_type != VREG) {
@@ -567,8 +586,13 @@ lookup_handle_rsrc_fork(vnode_t dp, struct nameidata *ndp, struct componentname
 			error = EPERM;
 			goto out;
 	}
+
+	nsflags = 0;
+	if (cnp->cn_flags & CN_RAW_ENCRYPTED)
+		nsflags |= NS_GETRAWENCRYPTED;
+
 	/* Ask the file system for the resource fork. */
-	error = vnode_getnamedstream(dp, &svp, XATTR_RESOURCEFORK_NAME, nsop, 0, ctx);
+	error = vnode_getnamedstream(dp, &svp, XATTR_RESOURCEFORK_NAME, nsop, nsflags, ctx);
 
 	/* During a create, it OK for stream vnode to be missing. */
 	if (error == ENOATTR || error == ENOENT) {
@@ -1720,24 +1744,33 @@ nameidone(struct nameidata *ndp)
 #if (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST)
 
 void
-kdebug_lookup_gen_events(long *dbg_parms, int dbg_namelen, void *dp, boolean_t lookup)
+kdebug_vfs_lookup(long *dbg_parms, int dbg_namelen, void *dp, uint32_t flags)
 {
 	int code;
 	unsigned int i;
+	bool lookup = flags & KDBG_VFS_LOOKUP_FLAG_LOOKUP;
+	bool noprocfilt = flags & KDBG_VFS_LOOKUP_FLAG_NOPROCFILT;
 
 	/*
 	 * In the event that we collect multiple, consecutive pathname
 	 * entries, we must mark the start of the path's string and the end.
 	 */
-	if (lookup == TRUE)
+	if (lookup) {
 		code = VFS_LOOKUP | DBG_FUNC_START;
-	else
+	} else {
 		code = VFS_LOOKUP_DONE | DBG_FUNC_START;
+	}
 
 	if (dbg_namelen <= (int)(3 * sizeof(long)))
 		code |= DBG_FUNC_END;
 
-	KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, code, kdebug_vnode(dp), dbg_parms[0], dbg_parms[1], dbg_parms[2], 0);
+	if (noprocfilt) {
+		KDBG_RELEASE_NOPROCFILT(code, kdebug_vnode(dp), dbg_parms[0],
+				dbg_parms[1], dbg_parms[2]);
+	} else {
+		KDBG_RELEASE(code, kdebug_vnode(dp), dbg_parms[0], dbg_parms[1],
+				dbg_parms[2]);
+	}
 
 	code &= ~DBG_FUNC_START;
 
@@ -1745,11 +1778,25 @@ kdebug_lookup_gen_events(long *dbg_parms, int dbg_namelen, void *dp, boolean_t l
 		if (dbg_namelen <= (int)(4 * sizeof(long)))
 			code |= DBG_FUNC_END;
 
-		KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, code, dbg_parms[i], dbg_parms[i+1], dbg_parms[i+2], dbg_parms[i+3], 0);
+		if (noprocfilt) {
+			KDBG_RELEASE_NOPROCFILT(code, dbg_parms[i], dbg_parms[i + 1],
+					dbg_parms[i + 2], dbg_parms[i + 3]);
+		} else {
+			KDBG_RELEASE(code, dbg_parms[i], dbg_parms[i + 1], dbg_parms[i + 2],
+					dbg_parms[i + 3]);
+		}
 	}
 }
 
-static void
+void
+kdebug_lookup_gen_events(long *dbg_parms, int dbg_namelen, void *dp,
+		boolean_t lookup)
+{
+	kdebug_vfs_lookup(dbg_parms, dbg_namelen, dp,
+			lookup ? KDBG_VFS_LOOKUP_FLAG_LOOKUP : 0);
+}
+
+void
 kdebug_lookup(vnode_t dp, struct componentname *cnp)
 {
 	int dbg_namelen;
@@ -1773,13 +1820,15 @@ kdebug_lookup(vnode_t dp, struct componentname *cnp)
 		       *(cnp->cn_nameptr + cnp->cn_namelen) ? '>' : 0,
 		       sizeof(dbg_parms) - dbg_namelen);
 	}
-	kdebug_lookup_gen_events(dbg_parms, dbg_namelen, (void *)dp, TRUE);
-}	
+	kdebug_vfs_lookup(dbg_parms, dbg_namelen, (void *)dp,
+			KDBG_VFS_LOOKUP_FLAG_LOOKUP);
+}
 
 #else /* (KDEBUG_LEVEL >= KDEBUG_LEVEL_IST) */
 
 void
-kdebug_lookup_gen_events(long *dbg_parms __unused, int dbg_namelen __unused, void *dp __unused)
+kdebug_vfs_lookup(long *dbg_parms __unused, int dbg_namelen __unused,
+		void *dp __unused, __unused uint32_t flags)
 {
 }