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commit ea5f10ba55fce68d1ed614ca33afdb38816f0830
Author: Frank Ch. Eigler <fche@redhat.com>
Date:   Mon Nov 16 18:54:11 2020 -0500

    PR26665: mokutil output parsing tweaks
    
    We encountered secureboot keys in the wild that didn't live up
    to the expectations of the current little state machine.  Tweaked
    regexps to accept Issuer: O= as well as Issuer: CN= lines.  With
    more verbosity, produces output on parsing process.

diff --git a/session.cxx b/session.cxx
index b5a8044..0437ca4 100644
--- a/session.cxx
+++ b/session.cxx
@@ -2859,6 +2859,9 @@ systemtap_session::get_mok_info()
       // PR26665: but only Systemtap MOK keys; there may be others.
       getline(out, line);
 
+      if (verbose > 3)
+        clog << "MOK parse state: " << state << " line: " << line << endl;
+      
       if (state == "SHA1") { // look for a new key fingerprint
 	if (! regexp_match(line, "^SHA1 Fingerprint: ([0-9a-f:]+)$", matches))
 	  {
@@ -2871,11 +2874,14 @@ systemtap_session::get_mok_info()
 	  }
 	// else stay in SHA1 state
       } else if (state == "Issuer") { // validate issuer
-	if (! regexp_match(line, "^[ \t]*Issuer: O=(.*)$", matches)) {
+	if (! regexp_match(line, "^[ \t]*Issuer: [A-Z]*=(.*)$", matches)) {
 	  if (verbose > 2)
 	    clog << "Issuer found: " << matches[1] << endl;
-	  if (! regexp_match(matches[1], "Systemtap", matches))
+	  if (! regexp_match(matches[1], "Systemtap", matches)) {
+            if (verbose > 2)
+              clog << "Recognized Systemtap MOK fingerprint: " << fingerprint << endl;
 	    mok_fingerprints.push_back(fingerprint);
+          }
 	  state = "SHA1"; // start looking for another key
 	}
       } else { // some other line in mokutil output ... there are plenty
commit 532eb9a1502026300a7f0b4bd287499101dd5803
Author: Frank Ch. Eigler <fche@redhat.com>
Date:   Tue Nov 17 16:34:59 2020 -0500

    PR26665 detect rhel8 (4.18) era kernel_is_locked_down() as procfs trigger
    
    A different older kernel API needs to be probed for rhel8 era detection
    of lockdown in effect.  Added an (undocumented) $SYSTEMTAP_NOSIGN env
    var to override automatic --use-server on lockdown, so that one can
    inspect runtime/autoconf* operation locally, without stap-server.

diff --git a/buildrun.cxx b/buildrun.cxx
index 9b4066d..9c8e648 100644
--- a/buildrun.cxx
+++ b/buildrun.cxx
@@ -517,6 +517,7 @@ compile_pass (systemtap_session& s)
   output_autoconf(s, o, cs, "autoconf-atomic_fetch_add_unless.c",
 		  "STAPCONF_ATOMIC_FETCH_ADD_UNLESS", NULL);
   output_autoconf(s, o, cs, "autoconf-lockdown-debugfs.c", "STAPCONF_LOCKDOWN_DEBUGFS", NULL);
+  output_autoconf(s, o, cs, "autoconf-lockdown-kernel.c", "STAPCONF_LOCKDOWN_KERNEL", NULL);
   
   // used by runtime/linux/netfilter.c
   output_exportconf(s, o2, "nf_register_hook", "STAPCONF_NF_REGISTER_HOOK");
diff --git a/runtime/linux/autoconf-lockdown-kernel.c b/runtime/linux/autoconf-lockdown-kernel.c
new file mode 100644
index 0000000..90c2414
--- /dev/null
+++ b/runtime/linux/autoconf-lockdown-kernel.c
@@ -0,0 +1,5 @@
+#include <linux/kernel.h>
+
+int foo(void) {
+  return kernel_is_locked_down("something");
+}
diff --git a/runtime/transport/transport.c b/runtime/transport/transport.c
index bb4a98b..5795533 100644
--- a/runtime/transport/transport.c
+++ b/runtime/transport/transport.c
@@ -123,6 +123,12 @@ static int _stp_transport_fs_init(const char *module_name)
 		dbug_trans(1, "choosing procfs_p=1\n");
         }
 #endif
+#ifdef STAPCONF_LOCKDOWN_KERNEL
+        if (!debugfs_p && kernel_is_locked_down ("debugfs")) {
+                procfs_p = 1;
+		dbug_trans(1, "choosing procfs_p=1\n");
+        }
+#endif
         if (!procfs_p) {
                 debugfs_p = 1;
 		dbug_trans(1, "choosing debugfs_p=1\n");
diff --git a/session.cxx b/session.cxx
index 0437ca4..36a4053 100644
--- a/session.cxx
+++ b/session.cxx
@@ -2804,7 +2804,9 @@ systemtap_session::modules_must_be_signed()
 
   if (getenv("SYSTEMTAP_SIGN"))
     return true;
-
+  if (getenv("SYSTEMTAP_NOSIGN"))
+    return false;
+  
   statm >> status;
   if (status == 'Y')
     return true;