Add support for DT_RUNPATH and DT_FLAGS

ok kettenis@

3 files changed, 69 insertions, 38 deletions

diff --git a/libexec/ld.so/library_subr.c b/libexec/ld.so/library_subr.c
index 07631c5c104..da476b8d309 100644
--- a/libexec/ld.so/library_subr.c
+++ b/libexec/ld.so/library_subr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: library_subr.c,v 1.45 2016/01/24 03:54:34 guenther Exp $ */
+/*	$OpenBSD: library_subr.c,v 1.46 2017/01/22 01:20:36 guenther Exp $ */
 
 /*
  * Copyright (c) 2002 Dale Rahn
@@ -286,21 +286,24 @@ _dl_find_loaded_shlib(const char *req_name, struct sod req_sod, int flags)
  *	     this will only match specific library version.
  *	   search path preceding library name
  *	     this will find largest minor version in path provided
- *	try the LD_LIBRARY_PATH specification (if present)
- *	   search hints for match in LD_LIBRARY_PATH dirs
- *           this will only match specific library version.
- *	   search LD_LIBRARY_PATH dirs for match.
- *           this will find largest minor version in first dir found.
- *	check DT_RPATH paths, (if present)
- *	   search hints for match in DT_RPATH dirs
- *           this will only match specific library version.
- *	   search DT_RPATH dirs for match.
- *           this will find largest minor version in first dir found.
- *	last look in default search directory, either as specified
- *      by ldconfig or default to '/usr/lib'
+ *
+ *	Otherwise, the name doesn't contain a '/':
+ *	search hints for the specific library version, trying in turn
+ *	paths from the following:
+ *	  - the LD_LIBRARY_PATH environment variable (if set)
+ *	  - the library's own DT_RUNPATH
+ *	  - if DT_RUNPATH wasn't set, then:
+ *	    - the library's own DT_RPATH
+ *	    - the executable's own DT_RPATH
+ *	  - the default search path set by ldconfig, or /usr/lib if unset
+ *
+ *	If the hints doesn't have an exact match, then we search
+ *	that exact same list of directories again, looking for a
+ *	lib with the correct major version.  If we find a match on
+ *	the major, then we take the match *in that directory* which
+ *	has the largest minor version
  */
 
-
 elf_object_t *
 _dl_load_shlib(const char *libname, elf_object_t *parent, int type, int flags)
 {
@@ -371,18 +374,28 @@ again:
 			goto done;
 	}
 
-	/* Check DT_RPATH.  */
-	if (parent->rpath != NULL) {
-		hint = _dl_find_shlib(&req_sod, parent->rpath, ignore_hints);
-		if (hint != NULL)
-			goto done;
-	}
-
-	/* Check main program's DT_RPATH, if parent != main program */
-	if (parent != _dl_objects && _dl_objects->rpath != NULL) {
-		hint = _dl_find_shlib(&req_sod, _dl_objects->rpath, ignore_hints);
+	/* Check DT_RUNPATH */
+	if (parent->runpath != NULL) {
+		hint = _dl_find_shlib(&req_sod, parent->runpath, ignore_hints);
 		if (hint != NULL)
 			goto done;
+	} else {
+		/* 
+		 * If DT_RUNPATH wasn't set then first check DT_RPATH,
+		 * followed by the main program's DT_RPATH.
+		 */
+		if (parent->rpath != NULL) {
+			hint = _dl_find_shlib(&req_sod, parent->rpath,
+			    ignore_hints);
+			if (hint != NULL)
+				goto done;
+		}
+		if (parent != _dl_objects && _dl_objects->rpath != NULL) {
+			hint = _dl_find_shlib(&req_sod, _dl_objects->rpath,
+			    ignore_hints);
+			if (hint != NULL)
+				goto done;
+		}
 	}
 
 	/* check 'standard' locations */
diff --git a/libexec/ld.so/resolve.c b/libexec/ld.so/resolve.c
index 02d96833cb2..e2e2267efe2 100644
--- a/libexec/ld.so/resolve.c
+++ b/libexec/ld.so/resolve.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: resolve.c,v 1.75 2016/08/23 06:46:17 kettenis Exp $ */
+/*	$OpenBSD: resolve.c,v 1.76 2017/01/22 01:20:36 guenther Exp $ */
 
 /*
  * Copyright (c) 1998 Per Fogelstrom, Opsycon AB
@@ -221,7 +221,7 @@ _dl_origin_path(elf_object_t *object, char *origin_path)
 }
 
 /*
- * Perform $ORIGIN substitutions on rpath
+ * Perform $ORIGIN substitutions on runpath and rpath
  */
 static void
 _dl_origin_subst(elf_object_t *object)
@@ -232,7 +232,10 @@ _dl_origin_subst(elf_object_t *object)
 	if (_dl_origin_path(object, origin_path) != 0)
 		return;
 
-	/* perform path substitutions on each segment of rpath */
+	/* perform path substitutions on each segment of runpath and rpath */
+	for (pp = object->runpath; *pp != NULL; pp++) {
+		_dl_origin_subst_path(object, origin_path, pp);
+	}
 	for (pp = object->rpath; *pp != NULL; pp++) {
 		_dl_origin_subst_path(object, origin_path, pp);
 	}
@@ -272,6 +275,15 @@ _dl_finalize_object(const char *objname, Elf_Dyn *dynp, Elf_Phdr *phdrp,
 			object->obj_flags |= DF_1_NOW;
 		if (dynp->d_tag == DT_FLAGS_1)
 			object->obj_flags |= dynp->d_un.d_val;
+		if (dynp->d_tag == DT_FLAGS) {
+			object->dyn.flags |= dynp->d_un.d_val;
+			if (dynp->d_un.d_val & DF_SYMBOLIC)
+				object->dyn.symbolic = 1;
+			if (dynp->d_un.d_val & DF_ORIGIN)
+				object->obj_flags |= DF_1_ORIGIN;
+			if (dynp->d_un.d_val & DF_BIND_NOW)
+				object->obj_flags |= DF_1_NOW;
+		}
 		if (dynp->d_tag == DT_RELACOUNT)
 			object->relacount = dynp->d_un.d_val;
 		if (dynp->d_tag == DT_RELCOUNT)
@@ -362,11 +374,18 @@ _dl_finalize_object(const char *objname, Elf_Dyn *dynp, Elf_Phdr *phdrp,
 	TAILQ_INIT(&object->grpsym_list);
 	TAILQ_INIT(&object->grpref_list);
 
-	if (object->dyn.rpath) {
+	if (object->dyn.runpath)
+		object->runpath = _dl_split_path(object->dyn.runpath);
+	/*
+	 * DT_RPATH is ignored if DT_RUNPATH is present...except in
+	 * the exe, whose DT_RPATH is a fallback for libs that don't
+	 * use DT_RUNPATH
+	 */
+	if (object->dyn.rpath && (object->runpath == NULL ||
+	    objtype == OBJTYPE_EXE))
 		object->rpath = _dl_split_path(object->dyn.rpath);
-		if ((object->obj_flags & DF_1_ORIGIN) && _dl_trust)
-			_dl_origin_subst(object);
-	}
+	if ((object->obj_flags & DF_1_ORIGIN) && _dl_trust)
+		_dl_origin_subst(object);
 
 	_dl_trace_object_setup(object);
 
@@ -406,12 +425,10 @@ _dl_cleanup_objects()
 	head = free_objects;
 	free_objects = NULL;
 	while (head != NULL) {
-		if (head->load_name)
-			_dl_free(head->load_name);
-		if (head->sod.sod_name)
-			_dl_free((char *)head->sod.sod_name);
-		if (head->rpath)
-			_dl_free_path(head->rpath);
+		_dl_free(head->load_name);
+		_dl_free((char *)head->sod.sod_name);
+		_dl_free_path(head->runpath);
+		_dl_free_path(head->rpath);
 		_dl_tailq_free(TAILQ_FIRST(&head->grpsym_list));
 		_dl_tailq_free(TAILQ_FIRST(&head->child_list));
 		_dl_tailq_free(TAILQ_FIRST(&head->grpref_list));
diff --git a/libexec/ld.so/resolve.h b/libexec/ld.so/resolve.h
index 2e35fc888cc..c8917f88037 100644
--- a/libexec/ld.so/resolve.h
+++ b/libexec/ld.so/resolve.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: resolve.h,v 1.81 2016/08/30 12:47:19 kettenis Exp $ */
+/*	$OpenBSD: resolve.h,v 1.82 2017/01/22 01:20:36 guenther Exp $ */
 
 /*
  * Copyright (c) 1998 Per Fogelstrom, Opsycon AB
@@ -169,6 +169,7 @@ struct elf_object {
 	unsigned int grpsym_gen;
 
 	char **rpath;
+	char **runpath;
 
 	/* nonzero if trace enabled for this object */
 	int traced;