X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=dlwrap.c;h=69ffbd16fc6dde0dace5289aba1986f900ca5725;hb=e90938cac9a539dc00c08b4439298cd05dada442;hp=3f91a870cb61e8741639f61564e324390e656ba6;hpb=4eb96c34ac01f908aa2eb491b5c872d7395f216b;p=fips

diff --git a/dlwrap.c b/dlwrap.c
index 3f91a87..69ffbd1 100644
--- a/dlwrap.c
+++ b/dlwrap.c
@@ -23,16 +23,10 @@
 #define _GNU_SOURCE
 #include <dlfcn.h>
 
-#include <stdio.h>
-#include <stdlib.h>
-
-#include <string.h>
+#include "fips.h"
 
 #include "dlwrap.h"
 
-#define STRNCMP_LITERAL(var, literal) \
-    strncmp ((var), (literal), sizeof (literal) - 1)
-
 void *libfips_handle;
 
 typedef void * (* fips_dlopen_t)(const char * filename, int flag);
@@ -47,28 +41,42 @@ void *
 dlopen (const char *filename, int flag)
 {
 	Dl_info info;
+	void *ret;
+
+	/* Before deciding whether to redirect this dlopen to our own
+	 * library, we call the real dlopen. This assures that any
+	 * expected side-effects from loading the intended library are
+	 * resolved. Below, we may still return a handle pointing to
+	 * our own library, and not what is opened here. */
+	ret = dlwrap_real_dlopen (filename, flag);
 
 	/* Not libGL, so just return real dlopen */
 	if (STRNCMP_LITERAL (filename, "libGL.so"))
-		return dlwrap_real_dlopen (filename, flag);
+		return ret;
 
-	/* Redirect all dlopens to libGL to our own wrapper library.
-	 * We find our own filename by looking up this very function
-	 * (that is, this "dlopen"), with dladdr).*/
-	if (dladdr (dlopen, &info)) {
-		libfips_handle = dlwrap_real_dlopen (info.dli_fname, flag);
+	/* Otherwise, for all libGL lookups we redirectl dlopens to
+	 * our own library. If we've resolved libfips_handle before,
+	 * our work is done. */
+	if (libfips_handle)
 		return libfips_handle;
-	} else {
+
+	/* We find our own filename by looking up this very function
+	 * (that is, this "dlopen"), with dladdr).*/
+	if (dladdr (dlopen, &info) == 0) {
 		fprintf (stderr, "Error: Failed to redirect dlopen of %s:\n",
 			 filename);
 		exit (1);
 	}
+
+	libfips_handle = dlwrap_real_dlopen (info.dli_fname, flag);
+
+	return libfips_handle;
 }
 
 void *
 dlwrap_real_dlopen (const char *filename, int flag)
 {
-	fips_dlopen_t real_dlopen = NULL;
+	static fips_dlopen_t real_dlopen = NULL;
 
 	if (! real_dlopen) {
 		real_dlopen = (fips_dlopen_t) dlwrap_real_dlsym (RTLD_NEXT, "dlopen");