Add option to objdump/readelf to disable access to debuginfod servers.

	* dwarf.c (use_debuginfod): New variable.  Set to 1.
	(load_separate_debug_info): Only call
	debuginfod_fetch_separate_debug_info is use_debuginfod is true.
	(dwarf_select_sections_by_names): Add do-not-use-debuginfod and
	use-debuginfod options.
	(dwarf_select_sections_by_letters): Add D and E options.
	* dwarf.h (use_debuginfod): New extern.
	* objdump.c (usage): Mention the new options.
	* readelf.c (usage): Likewise.
	* doc/binutils.texi: Document the new options.
	* doc/debug-options.texi: Describe the new options.
	* NEWS: Mention the new feature.
	* testsuite/binutils-all/debuginfod.exp: Add tests of the new
	options.

9 files changed, 105 insertions, 12 deletions

diff --git a/binutils/ChangeLog b/binutils/ChangeLog
index a355e18..213f871 100644
--- a/binutils/ChangeLog
+++ b/binutils/ChangeLog
@@ -1,3 +1,20 @@
+2022-03-10  Nick Clifton  <nickc@redhat.com>
+
+	* dwarf.c (use_debuginfod): New variable.  Set to 1.
+	(load_separate_debug_info): Only call
+	debuginfod_fetch_separate_debug_info is use_debuginfod is true.
+	(dwarf_select_sections_by_names): Add do-not-use-debuginfod and
+	use-debuginfod options.
+	(dwarf_select_sections_by_letters): Add D and E options.
+	* dwarf.h (use_debuginfod): New extern.
+	* objdump.c (usage): Mention the new options.
+	* readelf.c (usage): Likewise.
+	* doc/binutils.texi: Document the new options.
+	* doc/debug-options.texi: Describe the new options.
+	* NEWS: Mention the new feature.
+	* testsuite/binutils-all/debuginfod.exp: Add tests of the new
+	options.
+
 2021-03-06  Maciej W. Rozycki  <macro@orcam.me.uk>
 
 	* testsuite/binutils-all/mips/mips1-branch-alias.d: New test.
diff --git a/binutils/NEWS b/binutils/NEWS
index c188b46..3c44708 100644
--- a/binutils/NEWS
+++ b/binutils/NEWS
@@ -1,5 +1,8 @@
 -*- text -*-
 
+* Add an option to objdump and readelf to prevent attempts to access debuginfod
+  servers when following links.
+
 Changes in 2.38:
 
 * elfedit: Add --output-abiversion option to update ABIVERSION.
diff --git a/binutils/doc/binutils.texi b/binutils/doc/binutils.texi
index 288974b..c73837e 100644
--- a/binutils/doc/binutils.texi
+++ b/binutils/doc/binutils.texi
@@ -2246,6 +2246,8 @@ objdump [@option{-a}|@option{--archive-headers}]
          @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
         [@option{-WK}|@option{--dwarf=follow-links}]
         [@option{-WN}|@option{--dwarf=no-follow-links}]
+        [@option{-wD}|@option{--dwarf=use-debuginfod}]
+        [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
         [@option{-L}|@option{--process-links}]
         [@option{--ctf=}@var{section}]
         [@option{-G}|@option{--stabs}]
@@ -4883,6 +4885,8 @@ readelf [@option{-a}|@option{--all}]
          @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
         [@option{-wK}|@option{--debug-dump=follow-links}]
         [@option{-wN}|@option{--debug-dump=no-follow-links}]
+        [@option{-wD}|@option{--debug-dump=use-debuginfod}]
+        [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
         [@option{-P}|@option{--process-links}]
         [@option{--dwarf-depth=@var{n}}]
         [@option{--dwarf-start=@var{n}}]
@@ -5508,7 +5512,8 @@ deduced from the input file
 @cindex separate debug files
 
 debuginfod is a web service that indexes ELF/DWARF debugging resources
-by build-id and serves them over HTTP.
+by build-id and serves them over HTTP.  For more information see:
+@emph{https://sourceware.org/elfutils/Debuginfod.html}
 
 Binutils can be built with the debuginfod client library
 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
@@ -5520,6 +5525,10 @@ separate debug files when the files are otherwise not found.
 debuginfod is packaged with elfutils, starting with version 0.178.
 You can get the latest version from `https://sourceware.org/elfutils/'.
 
+The DWARF info dumping tools (@command{readelf} and @command{objdump})
+have options to control when they should access the debuginfod
+servers.  By default this access is enabled.
+
 @node Reporting Bugs
 @chapter Reporting Bugs
 @cindex bugs
diff --git a/binutils/doc/debug.options.texi b/binutils/doc/debug.options.texi
index dbe74ff..26477ec 100644
--- a/binutils/doc/debug.options.texi
+++ b/binutils/doc/debug.options.texi
@@ -68,10 +68,27 @@ chosen when configuring the binutils via the
 @option{--enable-follow-debug-links=no} options.  If these are not
 used then the default is to enable the following of debug links.
 
+Note - if support for the debuginfod protocol was enabled when the
+binutils were built then this option will also include an attempt to
+contact any debuginfod servers mentioned in the @var{DEBUGINFOD_URLS}
+environment variable.  This could take some time to resolve.  This
+behaviour can be disabled via the @option{=do-not-use-debuginfod} debug
+option.
+
 @item N
 @itemx =no-follow-links
 Disables the following of links to separate debug info files.
 
+@item D
+@itemx =use-debuginfod
+Enables contacting debuginfod servers if there is a need to follow
+debug links.  This is the default behaviour.
+
+@item E
+@itemx =do-not-use-debuginfod
+Disables contacting debuginfod servers when there is a need to follow
+debug links.
+
 @item l
 @itemx =rawline
 Displays the contents of the @samp{.debug_line} section in a raw
diff --git a/binutils/dwarf.c b/binutils/dwarf.c
index bc33e9f..15b3c81 100644
--- a/binutils/dwarf.c
+++ b/binutils/dwarf.c
@@ -109,6 +109,9 @@ int do_debug_cu_index;
 int do_wide;
 int do_debug_links;
 int do_follow_links = DEFAULT_FOR_FOLLOW_LINKS;
+#ifdef HAVE_LIBDEBUGINFOD
+int use_debuginfod = 1;
+#endif
 bool do_checks;
 
 int dwarf_cutoff_level = -1;
@@ -11038,7 +11041,7 @@ debuginfod_fetch_separate_debug_info (struct dwarf_section * section,
 
   return false;
 }
-#endif
+#endif /* HAVE_LIBDEBUGINFOD  */
 
 static void *
 load_separate_debug_info (const char *            main_filename,
@@ -11157,9 +11160,10 @@ load_separate_debug_info (const char *            main_filename,
   {
     char * tmp_filename;
 
-    if (debuginfod_fetch_separate_debug_info (xlink,
-                                              & tmp_filename,
-                                              file))
+    if (use_debuginfod
+	&& debuginfod_fetch_separate_debug_info (xlink,
+						 & tmp_filename,
+						 file))
       {
         /* File successfully downloaded from server, replace
            debug_filename with the file's path.  */
@@ -11207,13 +11211,15 @@ load_separate_debug_info (const char *            main_filename,
       warn (_("tried: %s\n"), debug_filename);
 
 #if HAVE_LIBDEBUGINFOD
-      {
-	char *urls = getenv (DEBUGINFOD_URLS_ENV_VAR);
-	if (urls == NULL)
-	  urls = "";
+      if (use_debuginfod)
+	{
+	  char *urls = getenv (DEBUGINFOD_URLS_ENV_VAR);
 
-	warn (_("tried: DEBUGINFOD_URLS=%s\n"), urls);
-      }
+	  if (urls == NULL)
+	    urls = "";
+
+	  warn (_("tried: DEBUGINFOD_URLS=%s\n"), urls);
+	}
 #endif
     }
 
@@ -11707,6 +11713,9 @@ dwarf_select_sections_by_names (const char *names)
       { "aranges", & do_debug_aranges, 1 },
       { "cu_index", & do_debug_cu_index, 1 },
       { "decodedline", & do_debug_lines, FLAG_DEBUG_LINES_DECODED },
+#ifdef HAVE_LIBDEBUGINFOD
+      { "do-not-use-debuginfod", & use_debuginfod, 0 },
+#endif
       { "follow-links", & do_follow_links, 1 },
       { "frames", & do_debug_frames, 1 },
       { "frames-interp", & do_debug_frames_interp, 1 },
@@ -11730,6 +11739,9 @@ dwarf_select_sections_by_names (const char *names)
       { "trace_abbrev", & do_trace_abbrevs, 1 },
       { "trace_aranges", & do_trace_aranges, 1 },
       { "trace_info", & do_trace_info, 1 },
+#ifdef HAVE_LIBDEBUGINFOD
+      { "use-debuginfod", & use_debuginfod, 1 },
+#endif
       { NULL, NULL, 0 }
     };
 
@@ -11783,6 +11795,10 @@ dwarf_select_sections_by_letters (const char *letters)
       case 'A':	do_debug_addr = 1; break;
       case 'a':	do_debug_abbrevs = 1; break;
       case 'c':	do_debug_cu_index = 1; break;
+#ifdef HAVE_LIBDEBUGINFOD
+      case 'D': use_debuginfod = 1; break;
+      case 'E': use_debuginfod = 0; break;
+#endif
       case 'F':	do_debug_frames_interp = 1; /* Fall through.  */
       case 'f':	do_debug_frames = 1; break;
       case 'g':	do_gdb_index = 1; break;
diff --git a/binutils/dwarf.h b/binutils/dwarf.h
index 1843071..4fc62ab 100644
--- a/binutils/dwarf.h
+++ b/binutils/dwarf.h
@@ -224,6 +224,9 @@ extern int do_debug_cu_index;
 extern int do_wide;
 extern int do_debug_links;
 extern int do_follow_links;
+#ifdef HAVE_LIBDEBUGINFOD
+extern int use_debuginfod;
+#endif
 extern bool do_checks;
 
 extern int dwarf_cutoff_level;
diff --git a/binutils/objdump.c b/binutils/objdump.c
index 24e9186..8e1c9cb 100644
--- a/binutils/objdump.c
+++ b/binutils/objdump.c
@@ -282,6 +282,14 @@ usage (FILE *stream, int status)
                            Do not follow links to separate debug info files\n\
                             (default)\n"));
 #endif
+#if HAVE_LIBDEBUGINFOD
+  fprintf (stream, _("\
+  -WD --dwarf=use-debuginfod\n\
+                           When following links, also query debuginfod servers (default)\n"));
+  fprintf (stream, _("\
+  -WE --dwarf=do-not-use-debuginfod\n\
+                           When following links, do not query debuginfod servers\n"));
+#endif
   fprintf (stream, _("\
   -L, --process-links      Display the contents of non-debug sections in\n\
                             separate debuginfo files.  (Implies -WK)\n"));
diff --git a/binutils/readelf.c b/binutils/readelf.c
index 16efe1d..8b46052 100644
--- a/binutils/readelf.c
+++ b/binutils/readelf.c
@@ -5127,6 +5127,14 @@ usage (FILE * stream)
                          Do not follow links to separate debug info files\n\
                           (default)\n"));
 #endif
+#if HAVE_LIBDEBUGINFOD
+  fprintf (stream, _("\
+  -wD --debug-dump=use-debuginfod\n\
+                         When following links, also query debuginfod servers (default)\n"));
+  fprintf (stream, _("\
+  -wE --debug-dump=do-not-use-debuginfod\n\
+                         When following links, do not query debuginfod servers\n"));
+#endif
   fprintf (stream, _("\
   --dwarf-depth=N        Do not display DIEs at depth N or greater\n"));
   fprintf (stream, _("\
diff --git a/binutils/testsuite/binutils-all/debuginfod.exp b/binutils/testsuite/binutils-all/debuginfod.exp
index 96543b2..f5935ad 100644
--- a/binutils/testsuite/binutils-all/debuginfod.exp
+++ b/binutils/testsuite/binutils-all/debuginfod.exp
@@ -185,8 +185,14 @@ proc test_fetch_debugaltlink { prog progargs } {
 }
 
 if { [regexp ".*DEBUGINFOD.*" $conf_objdump] } {
-    test_fetch_debuglink $OBJDUMP "-W"
+    test_fetch_debuglink $OBJDUMP "-W -WD"
     test_fetch_debugaltlink $OBJDUMP "-Wk"
+
+    set test "disabling debuginfod access"
+    setup_xfail *-*-*
+    test_fetch_debuglink $OBJDUMP "-W -WE"
+    set test "debuginfod"
+
 } else {
     untested "$test (objdump not configured with debuginfod)"
 }
@@ -194,6 +200,12 @@ if { [regexp ".*DEBUGINFOD.*" $conf_objdump] } {
 if { [regexp ".*DEBUGINFOD.*" $conf_readelf] } {
     test_fetch_debuglink $READELF "-w"
     test_fetch_debugaltlink $READELF "-wk"
+
+    set test "disabling debuginfod access"
+    setup_xfail *-*-*
+    test_fetch_debuglink $READELF "-w -wE"
+    set test "debuginfod"
+
 } else {
     untested "$test (readelf not configured with debuginfod)"
 }