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diff -up aide-0.15.1/src/do_md.c.prelinkwarn aide-0.15.1/src/do_md.c
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--- aide-0.15.1/src/do_md.c.prelinkwarn	2010-08-08 19:39:31.000000000 +0200
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+++ aide-0.15.1/src/do_md.c	2013-11-08 13:13:54.634961991 +0100
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@@ -70,6 +70,40 @@
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 #ifdef WITH_PRELINK
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 #include <sys/wait.h>
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 #include <gelf.h>
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+#include <stdbool.h>
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+
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+bool g_prelink_present = false;
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+bool g_prelink_detect = true;
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+bool g_noprelink_warn = true;
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+
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+bool prelink_present(void)
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+{
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+	/* don't perform the check if we already did it */
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+	if (!g_prelink_detect)
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+		return g_prelink_present;
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+
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+	/* check whether the prelink binary is present and executable */
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+	if (access(PRELINK_PATH, X_OK) == 0)
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+		g_prelink_present = true;
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+	else
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+		g_prelink_present = false;
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+
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+	g_prelink_detect = false;
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+	return g_prelink_present;
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+}
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+
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+void noprelink_warn(void)
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+{
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+	if (g_noprelink_warn) {
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+		error(0,
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+		      "WARNING: AIDE detected prelinked binary objects on your"
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+		      " system but the prelink tool (%s) is missing!\n", PRELINK_PATH);
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+		error(0,
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+		      "WARNING: prelinked files will be processed without a prelink undo operation!"
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+		      " Please install prelink to fix this.\n");
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+		g_noprelink_warn = false;
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+	}
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+}
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 /*
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  *  Is file descriptor prelinked binary/library?
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@@ -265,12 +299,19 @@ void calc_md(struct AIDE_STAT_TYPE* old_
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      */
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     pid=0;
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     if ( is_prelinked(filedes) ) {
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-      close(filedes);
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-      pid = open_prelinked(line->filename, &filedes);
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-      if (pid == 0) {
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-        error(0, "Error on starting prelink undo\n");
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-	return;
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-      }
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+	    /* first detect whether the prelink binary is available */
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+	    if (prelink_present()) {
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+		    close(filedes);
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+		    pid = open_prelinked(line->filename, &filedes);
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+		    if (pid == 0) {
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+			    error(0, "Error on starting prelink undo\n");
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+			    return;
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+		    }
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+	    } else {
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+		    /* we've detected a prelinked file but the prelink binary is not available */
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+		    /* warn the user about this situation (once) and process the file as is */
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+		    noprelink_warn();
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+	    }
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     }
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 #endif
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@@ -296,6 +337,7 @@ void calc_md(struct AIDE_STAT_TYPE* old_
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 #ifdef __hpux
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            buf = mmap(0,r_size,PROT_READ,MAP_PRIVATE,filedes,curpos);
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 #else
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+
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            buf = mmap(0,r_size,PROT_READ,MAP_SHARED,filedes,curpos);
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 #endif
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            curpos+=r_size;