gpg: Move key cleaning functions to a separate file.

* g10/trust.c (mark_usable_uid_certs, clean_sigs_from_uid)
(clean_uid_from_key, clean_one_uid, clean_key): Move to ...
* g10/key-clean.c: new file.
* g10/key-clean.h: New.
* g10/Makefile.am (gpg_sources): Add new files.
* g10/export.c, g10/import.c, g10/keyedit.c, g10/trustdb.c: Include
new header.
* g10/trustdb.h (struct key_item, is_in_klist): Move to ...
* g10/keydb.h: here.
--

Signed-off-by: Werner Koch <[email protected]>

10 files changed, 495 insertions, 429 deletions

diff --git a/g10/Makefile.am b/g10/Makefile.am
index b8b92d702..3b4464364 100644
--- a/g10/Makefile.am
+++ b/g10/Makefile.am
@@ -152,6 +152,7 @@ gpg_sources = server.c          \
 	      trust.c $(trust_source) $(tofu_source) \
 	      $(card_source) \
 	      exec.c exec.h \
+              key-clean.c key-clean.h \
 	      key-check.c key-check.h
 
 gpg_SOURCES  = gpg.c \
diff --git a/g10/export.c b/g10/export.c
index c538dc1f1..44cf075b0 100644
--- a/g10/export.c
+++ b/g10/export.c
@@ -41,6 +41,8 @@
 #include "../common/init.h"
 #include "trustdb.h"
 #include "call-agent.h"
+#include "key-clean.h"
+
 
 /* An object to keep track of subkeys. */
 struct subkey_list_s
diff --git a/g10/import.c b/g10/import.c
index 5be7952d6..757063eea 100644
--- a/g10/import.c
+++ b/g10/import.c
@@ -41,6 +41,7 @@
 #include "../common/init.h"
 #include "../common/mbox-util.h"
 #include "key-check.h"
+#include "key-clean.h"
 
 
 struct import_stats_s
diff --git a/g10/key-clean.c b/g10/key-clean.c
new file mode 100644
index 000000000..d022ff44d
--- /dev/null
+++ b/g10/key-clean.c
@@ -0,0 +1,422 @@
+/* key-clean.c - Functions to clean a keyblock
+ * Copyright (C) 1998-2008, 2010-2011 Free Software Foundation, Inc.
+ * Copyright (C) 2014, 2016-2018  Werner Koch
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "gpg.h"
+#include "keydb.h"
+#include "../common/util.h"
+#include "../common/host2net.h"
+#include "../common/i18n.h"
+#include "options.h"
+#include "packet.h"
+#include "main.h"
+#include "key-clean.h"
+
+
+/*
+ * Mark the signature of the given UID which are used to certify it.
+ * To do this, we first revmove all signatures which are not valid and
+ * from the remain ones we look for the latest one.  If this is not a
+ * certification revocation signature we mark the signature by setting
+ * node flag bit 8.  Revocations are marked with flag 11, and sigs
+ * from unavailable keys are marked with flag 12.  Note that flag bits
+ * 9 and 10 are used for internal purposes.
+ */
+void
+mark_usable_uid_certs (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
+                       u32 *main_kid, struct key_item *klist,
+                       u32 curtime, u32 *next_expire)
+{
+  kbnode_t node;
+  PKT_signature *sig;
+
+  /* First check all signatures.  */
+  for (node=uidnode->next; node; node = node->next)
+    {
+      int rc;
+
+      node->flag &= ~(1<<8 | 1<<9 | 1<<10 | 1<<11 | 1<<12);
+      if (node->pkt->pkttype == PKT_USER_ID
+          || node->pkt->pkttype == PKT_PUBLIC_SUBKEY
+          || node->pkt->pkttype == PKT_SECRET_SUBKEY)
+        break; /* ready */
+      if (node->pkt->pkttype != PKT_SIGNATURE)
+        continue;
+      sig = node->pkt->pkt.signature;
+      if (main_kid
+	  && sig->keyid[0] == main_kid[0] && sig->keyid[1] == main_kid[1])
+        continue; /* ignore self-signatures if we pass in a main_kid */
+      if (!IS_UID_SIG(sig) && !IS_UID_REV(sig))
+        continue; /* we only look at these signature classes */
+      if(sig->sig_class>=0x11 && sig->sig_class<=0x13 &&
+	 sig->sig_class-0x10<opt.min_cert_level)
+	continue; /* treat anything under our min_cert_level as an
+		     invalid signature */
+      if (klist && !is_in_klist (klist, sig))
+        continue;  /* no need to check it then */
+      if ((rc=check_key_signature (ctrl, keyblock, node, NULL)))
+	{
+	  /* we ignore anything that won't verify, but tag the
+	     no_pubkey case */
+	  if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY)
+            node->flag |= 1<<12;
+          continue;
+        }
+      node->flag |= 1<<9;
+    }
+  /* Reset the remaining flags. */
+  for (; node; node = node->next)
+    node->flag &= ~(1<<8 | 1<<9 | 1<<10 | 1<<11 | 1<<12);
+
+  /* kbnode flag usage: bit 9 is here set for signatures to consider,
+   * bit 10 will be set by the loop to keep track of keyIDs already
+   * processed, bit 8 will be set for the usable signatures, and bit
+   * 11 will be set for usable revocations. */
+
+  /* For each cert figure out the latest valid one.  */
+  for (node=uidnode->next; node; node = node->next)
+    {
+      KBNODE n, signode;
+      u32 kid[2];
+      u32 sigdate;
+
+      if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY
+          || node->pkt->pkttype == PKT_SECRET_SUBKEY)
+        break;
+      if ( !(node->flag & (1<<9)) )
+        continue; /* not a node to look at */
+      if ( (node->flag & (1<<10)) )
+        continue; /* signature with a keyID already processed */
+      node->flag |= (1<<10); /* mark this node as processed */
+      sig = node->pkt->pkt.signature;
+      signode = node;
+      sigdate = sig->timestamp;
+      kid[0] = sig->keyid[0]; kid[1] = sig->keyid[1];
+
+      /* Now find the latest and greatest signature */
+      for (n=uidnode->next; n; n = n->next)
+        {
+          if (n->pkt->pkttype == PKT_PUBLIC_SUBKEY
+              || n->pkt->pkttype == PKT_SECRET_SUBKEY)
+            break;
+          if ( !(n->flag & (1<<9)) )
+            continue;
+          if ( (n->flag & (1<<10)) )
+            continue; /* shortcut already processed signatures */
+          sig = n->pkt->pkt.signature;
+          if (kid[0] != sig->keyid[0] || kid[1] != sig->keyid[1])
+            continue;
+          n->flag |= (1<<10); /* mark this node as processed */
+
+	  /* If signode is nonrevocable and unexpired and n isn't,
+             then take signode (skip).  It doesn't matter which is
+             older: if signode was older then we don't want to take n
+             as signode is nonrevocable.  If n was older then we're
+             automatically fine. */
+
+	  if(((IS_UID_SIG(signode->pkt->pkt.signature) &&
+	       !signode->pkt->pkt.signature->flags.revocable &&
+	       (signode->pkt->pkt.signature->expiredate==0 ||
+		signode->pkt->pkt.signature->expiredate>curtime))) &&
+	     (!(IS_UID_SIG(n->pkt->pkt.signature) &&
+		!n->pkt->pkt.signature->flags.revocable &&
+		(n->pkt->pkt.signature->expiredate==0 ||
+		 n->pkt->pkt.signature->expiredate>curtime))))
+	    continue;
+
+	  /* If n is nonrevocable and unexpired and signode isn't,
+             then take n.  Again, it doesn't matter which is older: if
+             n was older then we don't want to take signode as n is
+             nonrevocable.  If signode was older then we're
+             automatically fine. */
+
+	  if((!(IS_UID_SIG(signode->pkt->pkt.signature) &&
+		!signode->pkt->pkt.signature->flags.revocable &&
+		(signode->pkt->pkt.signature->expiredate==0 ||
+		 signode->pkt->pkt.signature->expiredate>curtime))) &&
+	     ((IS_UID_SIG(n->pkt->pkt.signature) &&
+	       !n->pkt->pkt.signature->flags.revocable &&
+	       (n->pkt->pkt.signature->expiredate==0 ||
+		n->pkt->pkt.signature->expiredate>curtime))))
+            {
+              signode = n;
+              sigdate = sig->timestamp;
+	      continue;
+            }
+
+	  /* At this point, if it's newer, it goes in as the only
+             remaining possibilities are signode and n are both either
+             revocable or expired or both nonrevocable and unexpired.
+             If the timestamps are equal take the later ordered
+             packet, presuming that the key packets are hopefully in
+             their original order. */
+
+          if (sig->timestamp >= sigdate)
+            {
+              signode = n;
+              sigdate = sig->timestamp;
+            }
+        }
+
+      sig = signode->pkt->pkt.signature;
+      if (IS_UID_SIG (sig))
+        { /* this seems to be a usable one which is not revoked.
+           * Just need to check whether there is an expiration time,
+           * We do the expired certification after finding a suitable
+           * certification, the assumption is that a signator does not
+           * want that after the expiration of his certificate the
+           * system falls back to an older certification which has a
+           * different expiration time */
+          const byte *p;
+          u32 expire;
+
+          p = parse_sig_subpkt (sig->hashed, SIGSUBPKT_SIG_EXPIRE, NULL );
+          expire = p? sig->timestamp + buf32_to_u32(p) : 0;
+
+          if (expire==0 || expire > curtime )
+            {
+              signode->flag |= (1<<8); /* yeah, found a good cert */
+              if (next_expire && expire && expire < *next_expire)
+                *next_expire = expire;
+            }
+        }
+      else
+	signode->flag |= (1<<11);
+    }
+}
+
+
+static int
+clean_sigs_from_uid (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
+                     int noisy, int self_only)
+{
+  int deleted = 0;
+  kbnode_t node;
+  u32 keyid[2];
+
+  log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY
+              || keyblock->pkt->pkttype == PKT_SECRET_KEY);
+
+  keyid_from_pk (keyblock->pkt->pkt.public_key, keyid);
+
+  /* Passing in a 0 for current time here means that we'll never weed
+     out an expired sig.  This is correct behavior since we want to
+     keep the most recent expired sig in a series. */
+  mark_usable_uid_certs (ctrl, keyblock, uidnode, NULL, NULL, 0, NULL);
+
+  /* What we want to do here is remove signatures that are not
+     considered as part of the trust calculations.  Thus, all invalid
+     signatures are out, as are any signatures that aren't the last of
+     a series of uid sigs or revocations It breaks down like this:
+     coming out of mark_usable_uid_certs, if a sig is unflagged, it is
+     not even a candidate.  If a sig has flag 9 or 10, that means it
+     was selected as a candidate and vetted.  If a sig has flag 8 it
+     is a usable signature.  If a sig has flag 11 it is a usable
+     revocation.  If a sig has flag 12 it was issued by an unavailable
+     key.  "Usable" here means the most recent valid
+     signature/revocation in a series from a particular signer.
+
+     Delete everything that isn't a usable uid sig (which might be
+     expired), a usable revocation, or a sig from an unavailable
+     key. */
+
+  for (node=uidnode->next;
+       node && node->pkt->pkttype==PKT_SIGNATURE;
+       node=node->next)
+    {
+      int keep;
+
+      keep = self_only? (node->pkt->pkt.signature->keyid[0] == keyid[0]
+                         && node->pkt->pkt.signature->keyid[1] == keyid[1]) : 1;
+
+      /* Keep usable uid sigs ... */
+      if ((node->flag & (1<<8)) && keep)
+	continue;
+
+      /* ... and usable revocations... */
+      if ((node->flag & (1<<11)) && keep)
+	continue;
+
+      /* ... and sigs from unavailable keys. */
+      /* disabled for now since more people seem to want sigs from
+	 unavailable keys removed altogether.  */
+      /*
+	if(node->flag & (1<<12))
+	continue;
+      */
+
+      /* Everything else we delete */
+
+      /* At this point, if 12 is set, the signing key was unavailable.
+	 If 9 or 10 is set, it's superseded.  Otherwise, it's
+	 invalid. */
+
+      if (noisy)
+	log_info ("removing signature from key %s on user ID \"%s\": %s\n",
+                  keystr (node->pkt->pkt.signature->keyid),
+                  uidnode->pkt->pkt.user_id->name,
+                  node->flag&(1<<12)? "key unavailable":
+                  node->flag&(1<<9)?  "signature superseded"
+                  /* */               :"invalid signature"  );
+
+      delete_kbnode (node);
+      deleted++;
+    }
+
+  return deleted;
+}
+
+
+/* This is substantially easier than clean_sigs_from_uid since we just
+   have to establish if the uid has a valid self-sig, is not revoked,
+   and is not expired.  Note that this does not take into account
+   whether the uid has a trust path to it - just whether the keyholder
+   themselves has certified the uid.  Returns true if the uid was
+   compacted.  To "compact" a user ID, we simply remove ALL signatures
+   except the self-sig that caused the user ID to be remove-worthy.
+   We don't actually remove the user ID packet itself since it might
+   be resurrected in a later merge.  Note that this function requires
+   that the caller has already done a merge_keys_and_selfsig().
+
+   TODO: change the import code to allow importing a uid with only a
+   revocation if the uid already exists on the keyring. */
+
+static int
+clean_uid_from_key (kbnode_t keyblock, kbnode_t uidnode, int noisy)
+{
+  kbnode_t node;
+  PKT_user_id *uid = uidnode->pkt->pkt.user_id;
+  int deleted = 0;
+
+  log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY
+              || keyblock->pkt->pkttype == PKT_SECRET_KEY);
+  log_assert (uidnode->pkt->pkttype==PKT_USER_ID);
+
+  /* Skip valid user IDs, compacted user IDs, and non-self-signed user
+     IDs if --allow-non-selfsigned-uid is set. */
+  if (uid->created
+      || uid->flags.compacted
+      || (!uid->flags.expired && !uid->flags.revoked && opt.allow_non_selfsigned_uid))
+    return 0;
+
+  for (node=uidnode->next;
+       node && node->pkt->pkttype == PKT_SIGNATURE;
+      node=node->next)
+    {
+      if (!node->pkt->pkt.signature->flags.chosen_selfsig)
+        {
+          delete_kbnode (node);
+          deleted = 1;
+          uidnode->pkt->pkt.user_id->flags.compacted = 1;
+        }
+    }
+
+  if (noisy)
+    {
+      const char *reason;
+      char *user = utf8_to_native (uid->name, uid->len, 0);
+
+      if (uid->flags.revoked)
+	reason = _("revoked");
+      else if (uid->flags.expired)
+	reason = _("expired");
+      else
+	reason = _("invalid");
+
+      log_info ("compacting user ID \"%s\" on key %s: %s\n",
+                user, keystr_from_pk (keyblock->pkt->pkt.public_key),
+                reason);
+
+      xfree (user);
+    }
+
+  return deleted;
+}
+
+
+/* Needs to be called after a merge_keys_and_selfsig() */
+void
+clean_one_uid (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
+               int noisy, int self_only, int *uids_cleaned, int *sigs_cleaned)
+{
+  int dummy = 0;
+
+  log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY
+              || keyblock->pkt->pkttype == PKT_SECRET_KEY);
+  log_assert (uidnode->pkt->pkttype==PKT_USER_ID);
+
+  if (!uids_cleaned)
+    uids_cleaned = &dummy;
+
+  if (!sigs_cleaned)
+    sigs_cleaned = &dummy;
+
+  /* Do clean_uid_from_key first since if it fires off, we don't have
+     to bother with the other.  */
+  *uids_cleaned += clean_uid_from_key (keyblock, uidnode, noisy);
+  if (!uidnode->pkt->pkt.user_id->flags.compacted)
+    *sigs_cleaned += clean_sigs_from_uid (ctrl, keyblock, uidnode,
+                                          noisy, self_only);
+}
+
+
+/* NB: This function marks the deleted nodes only and the caller is
+ * responsible to skip or remove them.  */
+void
+clean_key (ctrl_t ctrl, kbnode_t keyblock, int noisy, int self_only,
+           int *uids_cleaned, int *sigs_cleaned)
+{
+  kbnode_t node;
+
+  merge_keys_and_selfsig (ctrl, keyblock);
+
+  for (node = keyblock->next;
+       node && !(node->pkt->pkttype == PKT_PUBLIC_SUBKEY
+                    || node->pkt->pkttype == PKT_SECRET_SUBKEY);
+       node = node->next)
+    {
+      if (node->pkt->pkttype == PKT_USER_ID)
+        clean_one_uid (ctrl, keyblock, node, noisy, self_only,
+                       uids_cleaned, sigs_cleaned);
+    }
+
+  /* Remove bogus subkey binding signatures: The only signatures
+   * allowed are of class 0x18 and 0x28.  */
+  log_assert (!node || (node->pkt->pkttype == PKT_PUBLIC_SUBKEY
+                        || node->pkt->pkttype == PKT_SECRET_SUBKEY));
+  for (; node; node = node->next)
+    {
+      if (is_deleted_kbnode (node))
+        continue;
+      if (node->pkt->pkttype == PKT_SIGNATURE
+          && !(IS_SUBKEY_SIG (node->pkt->pkt.signature)
+                || IS_SUBKEY_REV (node->pkt->pkt.signature)))
+        {
+          delete_kbnode (node);
+          if (sigs_cleaned)
+            ++*sigs_cleaned;
+        }
+    }
+}
diff --git a/g10/key-clean.h b/g10/key-clean.h
new file mode 100644
index 000000000..4dfd9509c
--- /dev/null
+++ b/g10/key-clean.h
@@ -0,0 +1,37 @@
+/* key-clean.h - Functions to clean a keyblock
+ * Copyright (C) 2018 Werner Koch
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#ifndef GNUPG_G10_KEY_CLEAN_H
+#define GNUPG_G10_KEY_CLEAN_H
+
+#include "gpg.h"
+
+void mark_usable_uid_certs (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
+                            u32 *main_kid, struct key_item *klist,
+                            u32 curtime, u32 *next_expire);
+
+void clean_one_uid (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
+                    int noisy, int self_only,
+                    int *uids_cleaned, int *sigs_cleaned);
+void clean_key (ctrl_t ctrl, kbnode_t keyblock, int noisy, int self_only,
+                int *uids_cleaned,int *sigs_cleaned);
+
+
+#endif /*GNUPG_G10_KEY_CLEAN_H*/
diff --git a/g10/keydb.h b/g10/keydb.h
index ea0fa9ddd..9748e571e 100644
--- a/g10/keydb.h
+++ b/g10/keydb.h
@@ -64,6 +64,20 @@ struct kbnode_struct {
 #define is_cloned_kbnode(a)   ((a)->private_flag & 2)
 
 
+/*
+ * A structure to store key identification as well as some stuff
+ * needed for key validation.
+ */
+struct key_item {
+  struct key_item *next;
+  unsigned int ownertrust,min_ownertrust;
+  byte trust_depth;
+  byte trust_value;
+  char *trust_regexp;
+  u32 kid[2];
+};
+
+
 /* Bit flags used with build_pk_list.  */
 enum
   {
@@ -133,6 +147,22 @@ enum
   };
 
 
+/*
+ * Check whether the signature SIG is in the klist K.
+ */
+static inline struct key_item *
+is_in_klist (struct key_item *k, PKT_signature *sig)
+{
+  for (; k; k = k->next)
+    {
+      if (k->kid[0] == sig->keyid[0] && k->kid[1] == sig->keyid[1])
+        return k;
+    }
+  return NULL;
+}
+
+
+
 /*-- keydb.c --*/
 
 #define KEYDB_RESOURCE_FLAG_PRIMARY  2  /* The primary resource.  */
diff --git a/g10/keyedit.c b/g10/keyedit.c
index 00b4e7280..9716ed9d6 100644
--- a/g10/keyedit.c
+++ b/g10/keyedit.c
@@ -49,6 +49,7 @@
 #include "../common/host2net.h"
 #include "tofu.h"
 #include "key-check.h"
+#include "key-clean.h"
 #include "keyedit.h"
 
 static void show_prefs (PKT_user_id * uid, PKT_signature * selfsig,
diff --git a/g10/trust.c b/g10/trust.c
index 6d4f0e74b..bd1c89458 100644
--- a/g10/trust.c
+++ b/g10/trust.c
@@ -437,391 +437,3 @@ get_validity_string (ctrl_t ctrl, PKT_public_key *pk, PKT_user_id *uid)
     return _("revoked");
   return trust_value_to_string (trustlevel);
 }
-
-
-
-/*
- * Mark the signature of the given UID which are used to certify it.
- * To do this, we first revmove all signatures which are not valid and
- * from the remain ones we look for the latest one.  If this is not a
- * certification revocation signature we mark the signature by setting
- * node flag bit 8.  Revocations are marked with flag 11, and sigs
- * from unavailable keys are marked with flag 12.  Note that flag bits
- * 9 and 10 are used for internal purposes.
- */
-void
-mark_usable_uid_certs (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
-                       u32 *main_kid, struct key_item *klist,
-                       u32 curtime, u32 *next_expire)
-{
-  kbnode_t node;
-  PKT_signature *sig;
-
-  /* First check all signatures.  */
-  for (node=uidnode->next; node; node = node->next)
-    {
-      int rc;
-
-      node->flag &= ~(1<<8 | 1<<9 | 1<<10 | 1<<11 | 1<<12);
-      if (node->pkt->pkttype == PKT_USER_ID
-          || node->pkt->pkttype == PKT_PUBLIC_SUBKEY
-          || node->pkt->pkttype == PKT_SECRET_SUBKEY)
-        break; /* ready */
-      if (node->pkt->pkttype != PKT_SIGNATURE)
-        continue;
-      sig = node->pkt->pkt.signature;
-      if (main_kid
-	  && sig->keyid[0] == main_kid[0] && sig->keyid[1] == main_kid[1])
-        continue; /* ignore self-signatures if we pass in a main_kid */
-      if (!IS_UID_SIG(sig) && !IS_UID_REV(sig))
-        continue; /* we only look at these signature classes */
-      if(sig->sig_class>=0x11 && sig->sig_class<=0x13 &&
-	 sig->sig_class-0x10<opt.min_cert_level)
-	continue; /* treat anything under our min_cert_level as an
-		     invalid signature */
-      if (klist && !is_in_klist (klist, sig))
-        continue;  /* no need to check it then */
-      if ((rc=check_key_signature (ctrl, keyblock, node, NULL)))
-	{
-	  /* we ignore anything that won't verify, but tag the
-	     no_pubkey case */
-	  if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY)
-            node->flag |= 1<<12;
-          continue;
-        }
-      node->flag |= 1<<9;
-    }
-  /* Reset the remaining flags. */
-  for (; node; node = node->next)
-    node->flag &= ~(1<<8 | 1<<9 | 1<<10 | 1<<11 | 1<<12);
-
-  /* kbnode flag usage: bit 9 is here set for signatures to consider,
-   * bit 10 will be set by the loop to keep track of keyIDs already
-   * processed, bit 8 will be set for the usable signatures, and bit
-   * 11 will be set for usable revocations. */
-
-  /* For each cert figure out the latest valid one.  */
-  for (node=uidnode->next; node; node = node->next)
-    {
-      KBNODE n, signode;
-      u32 kid[2];
-      u32 sigdate;
-
-      if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY
-          || node->pkt->pkttype == PKT_SECRET_SUBKEY)
-        break;
-      if ( !(node->flag & (1<<9)) )
-        continue; /* not a node to look at */
-      if ( (node->flag & (1<<10)) )
-        continue; /* signature with a keyID already processed */
-      node->flag |= (1<<10); /* mark this node as processed */
-      sig = node->pkt->pkt.signature;
-      signode = node;
-      sigdate = sig->timestamp;
-      kid[0] = sig->keyid[0]; kid[1] = sig->keyid[1];
-
-      /* Now find the latest and greatest signature */
-      for (n=uidnode->next; n; n = n->next)
-        {
-          if (n->pkt->pkttype == PKT_PUBLIC_SUBKEY
-              || n->pkt->pkttype == PKT_SECRET_SUBKEY)
-            break;
-          if ( !(n->flag & (1<<9)) )
-            continue;
-          if ( (n->flag & (1<<10)) )
-            continue; /* shortcut already processed signatures */
-          sig = n->pkt->pkt.signature;
-          if (kid[0] != sig->keyid[0] || kid[1] != sig->keyid[1])
-            continue;
-          n->flag |= (1<<10); /* mark this node as processed */
-
-	  /* If signode is nonrevocable and unexpired and n isn't,
-             then take signode (skip).  It doesn't matter which is
-             older: if signode was older then we don't want to take n
-             as signode is nonrevocable.  If n was older then we're
-             automatically fine. */
-
-	  if(((IS_UID_SIG(signode->pkt->pkt.signature) &&
-	       !signode->pkt->pkt.signature->flags.revocable &&
-	       (signode->pkt->pkt.signature->expiredate==0 ||
-		signode->pkt->pkt.signature->expiredate>curtime))) &&
-	     (!(IS_UID_SIG(n->pkt->pkt.signature) &&
-		!n->pkt->pkt.signature->flags.revocable &&
-		(n->pkt->pkt.signature->expiredate==0 ||
-		 n->pkt->pkt.signature->expiredate>curtime))))
-	    continue;
-
-	  /* If n is nonrevocable and unexpired and signode isn't,
-             then take n.  Again, it doesn't matter which is older: if
-             n was older then we don't want to take signode as n is
-             nonrevocable.  If signode was older then we're
-             automatically fine. */
-
-	  if((!(IS_UID_SIG(signode->pkt->pkt.signature) &&
-		!signode->pkt->pkt.signature->flags.revocable &&
-		(signode->pkt->pkt.signature->expiredate==0 ||
-		 signode->pkt->pkt.signature->expiredate>curtime))) &&
-	     ((IS_UID_SIG(n->pkt->pkt.signature) &&
-	       !n->pkt->pkt.signature->flags.revocable &&
-	       (n->pkt->pkt.signature->expiredate==0 ||
-		n->pkt->pkt.signature->expiredate>curtime))))
-            {
-              signode = n;
-              sigdate = sig->timestamp;
-	      continue;
-            }
-
-	  /* At this point, if it's newer, it goes in as the only
-             remaining possibilities are signode and n are both either
-             revocable or expired or both nonrevocable and unexpired.
-             If the timestamps are equal take the later ordered
-             packet, presuming that the key packets are hopefully in
-             their original order. */
-
-          if (sig->timestamp >= sigdate)
-            {
-              signode = n;
-              sigdate = sig->timestamp;
-            }
-        }
-
-      sig = signode->pkt->pkt.signature;
-      if (IS_UID_SIG (sig))
-        { /* this seems to be a usable one which is not revoked.
-           * Just need to check whether there is an expiration time,
-           * We do the expired certification after finding a suitable
-           * certification, the assumption is that a signator does not
-           * want that after the expiration of his certificate the
-           * system falls back to an older certification which has a
-           * different expiration time */
-          const byte *p;
-          u32 expire;
-
-          p = parse_sig_subpkt (sig->hashed, SIGSUBPKT_SIG_EXPIRE, NULL );
-          expire = p? sig->timestamp + buf32_to_u32(p) : 0;
-
-          if (expire==0 || expire > curtime )
-            {
-              signode->flag |= (1<<8); /* yeah, found a good cert */
-              if (next_expire && expire && expire < *next_expire)
-                *next_expire = expire;
-            }
-        }
-      else
-	signode->flag |= (1<<11);
-    }
-}
-
-
-static int
-clean_sigs_from_uid (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
-                     int noisy, int self_only)
-{
-  int deleted = 0;
-  kbnode_t node;
-  u32 keyid[2];
-
-  log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY
-              || keyblock->pkt->pkttype == PKT_SECRET_KEY);
-
-  keyid_from_pk (keyblock->pkt->pkt.public_key, keyid);
-
-  /* Passing in a 0 for current time here means that we'll never weed
-     out an expired sig.  This is correct behavior since we want to
-     keep the most recent expired sig in a series. */
-  mark_usable_uid_certs (ctrl, keyblock, uidnode, NULL, NULL, 0, NULL);
-
-  /* What we want to do here is remove signatures that are not
-     considered as part of the trust calculations.  Thus, all invalid
-     signatures are out, as are any signatures that aren't the last of
-     a series of uid sigs or revocations It breaks down like this:
-     coming out of mark_usable_uid_certs, if a sig is unflagged, it is
-     not even a candidate.  If a sig has flag 9 or 10, that means it
-     was selected as a candidate and vetted.  If a sig has flag 8 it
-     is a usable signature.  If a sig has flag 11 it is a usable
-     revocation.  If a sig has flag 12 it was issued by an unavailable
-     key.  "Usable" here means the most recent valid
-     signature/revocation in a series from a particular signer.
-
-     Delete everything that isn't a usable uid sig (which might be
-     expired), a usable revocation, or a sig from an unavailable
-     key. */
-
-  for (node=uidnode->next;
-       node && node->pkt->pkttype==PKT_SIGNATURE;
-       node=node->next)
-    {
-      int keep;
-
-      keep = self_only? (node->pkt->pkt.signature->keyid[0] == keyid[0]
-                         && node->pkt->pkt.signature->keyid[1] == keyid[1]) : 1;
-
-      /* Keep usable uid sigs ... */
-      if ((node->flag & (1<<8)) && keep)
-	continue;
-
-      /* ... and usable revocations... */
-      if ((node->flag & (1<<11)) && keep)
-	continue;
-
-      /* ... and sigs from unavailable keys. */
-      /* disabled for now since more people seem to want sigs from
-	 unavailable keys removed altogether.  */
-      /*
-	if(node->flag & (1<<12))
-	continue;
-      */
-
-      /* Everything else we delete */
-
-      /* At this point, if 12 is set, the signing key was unavailable.
-	 If 9 or 10 is set, it's superseded.  Otherwise, it's
-	 invalid. */
-
-      if (noisy)
-	log_info ("removing signature from key %s on user ID \"%s\": %s\n",
-                  keystr (node->pkt->pkt.signature->keyid),
-                  uidnode->pkt->pkt.user_id->name,
-                  node->flag&(1<<12)? "key unavailable":
-                  node->flag&(1<<9)?  "signature superseded"
-                  /* */               :"invalid signature"  );
-
-      delete_kbnode (node);
-      deleted++;
-    }
-
-  return deleted;
-}
-
-
-/* This is substantially easier than clean_sigs_from_uid since we just
-   have to establish if the uid has a valid self-sig, is not revoked,
-   and is not expired.  Note that this does not take into account
-   whether the uid has a trust path to it - just whether the keyholder
-   themselves has certified the uid.  Returns true if the uid was
-   compacted.  To "compact" a user ID, we simply remove ALL signatures
-   except the self-sig that caused the user ID to be remove-worthy.
-   We don't actually remove the user ID packet itself since it might
-   be resurrected in a later merge.  Note that this function requires
-   that the caller has already done a merge_keys_and_selfsig().
-
-   TODO: change the import code to allow importing a uid with only a
-   revocation if the uid already exists on the keyring. */
-
-static int
-clean_uid_from_key (kbnode_t keyblock, kbnode_t uidnode, int noisy)
-{
-  kbnode_t node;
-  PKT_user_id *uid = uidnode->pkt->pkt.user_id;
-  int deleted = 0;
-
-  log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY
-              || keyblock->pkt->pkttype == PKT_SECRET_KEY);
-  log_assert (uidnode->pkt->pkttype==PKT_USER_ID);
-
-  /* Skip valid user IDs, compacted user IDs, and non-self-signed user
-     IDs if --allow-non-selfsigned-uid is set. */
-  if (uid->created
-      || uid->flags.compacted
-      || (!uid->flags.expired && !uid->flags.revoked && opt.allow_non_selfsigned_uid))
-    return 0;
-
-  for (node=uidnode->next;
-       node && node->pkt->pkttype == PKT_SIGNATURE;
-      node=node->next)
-    {
-      if (!node->pkt->pkt.signature->flags.chosen_selfsig)
-        {
-          delete_kbnode (node);
-          deleted = 1;
-          uidnode->pkt->pkt.user_id->flags.compacted = 1;
-        }
-    }
-
-  if (noisy)
-    {
-      const char *reason;
-      char *user = utf8_to_native (uid->name, uid->len, 0);
-
-      if (uid->flags.revoked)
-	reason = _("revoked");
-      else if (uid->flags.expired)
-	reason = _("expired");
-      else
-	reason = _("invalid");
-
-      log_info ("compacting user ID \"%s\" on key %s: %s\n",
-                user, keystr_from_pk (keyblock->pkt->pkt.public_key),
-                reason);
-
-      xfree (user);
-    }
-
-  return deleted;
-}
-
-
-/* Needs to be called after a merge_keys_and_selfsig() */
-void
-clean_one_uid (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
-               int noisy, int self_only, int *uids_cleaned, int *sigs_cleaned)
-{
-  int dummy = 0;
-
-  log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY
-              || keyblock->pkt->pkttype == PKT_SECRET_KEY);
-  log_assert (uidnode->pkt->pkttype==PKT_USER_ID);
-
-  if (!uids_cleaned)
-    uids_cleaned = &dummy;
-
-  if (!sigs_cleaned)
-    sigs_cleaned = &dummy;
-
-  /* Do clean_uid_from_key first since if it fires off, we don't have
-     to bother with the other.  */
-  *uids_cleaned += clean_uid_from_key (keyblock, uidnode, noisy);
-  if (!uidnode->pkt->pkt.user_id->flags.compacted)
-    *sigs_cleaned += clean_sigs_from_uid (ctrl, keyblock, uidnode,
-                                          noisy, self_only);
-}
-
-
-/* NB: This function marks the deleted nodes only and the caller is
- * responsible to skip or remove them.  */
-void
-clean_key (ctrl_t ctrl, kbnode_t keyblock, int noisy, int self_only,
-           int *uids_cleaned, int *sigs_cleaned)
-{
-  kbnode_t node;
-
-  merge_keys_and_selfsig (ctrl, keyblock);
-
-  for (node = keyblock->next;
-       node && !(node->pkt->pkttype == PKT_PUBLIC_SUBKEY
-                    || node->pkt->pkttype == PKT_SECRET_SUBKEY);
-       node = node->next)
-    {
-      if (node->pkt->pkttype == PKT_USER_ID)
-        clean_one_uid (ctrl, keyblock, node, noisy, self_only,
-                       uids_cleaned, sigs_cleaned);
-    }
-
-  /* Remove bogus subkey binding signatures: The only signatures
-   * allowed are of class 0x18 and 0x28.  */
-  log_assert (!node || (node->pkt->pkttype == PKT_PUBLIC_SUBKEY
-                        || node->pkt->pkttype == PKT_SECRET_SUBKEY));
-  for (; node; node = node->next)
-    {
-      if (is_deleted_kbnode (node))
-        continue;
-      if (node->pkt->pkttype == PKT_SIGNATURE
-          && !(IS_SUBKEY_SIG (node->pkt->pkt.signature)
-                || IS_SUBKEY_REV (node->pkt->pkt.signature)))
-        {
-          delete_kbnode (node);
-          if (sigs_cleaned)
-            ++*sigs_cleaned;
-        }
-    }
-}
diff --git a/g10/trustdb.c b/g10/trustdb.c
index 2c2d2394a..8ef6db542 100644
--- a/g10/trustdb.c
+++ b/g10/trustdb.c
@@ -41,6 +41,7 @@
 #include "tdbio.h"
 #include "trustdb.h"
 #include "tofu.h"
+#include "key-clean.h"
 
 
 typedef struct key_item **KeyHashTable; /* see new_key_hash_table() */
diff --git a/g10/trustdb.h b/g10/trustdb.h
index 4bc4ca971..d52fc53f2 100644
--- a/g10/trustdb.h
+++ b/g10/trustdb.h
@@ -46,36 +46,6 @@
 #define NAMEHASH_LEN  20
 
 
-/*
- * A structure to store key identification as well as some stuff needed
- * for validation
- */
-struct key_item {
-  struct key_item *next;
-  unsigned int ownertrust,min_ownertrust;
-  byte trust_depth;
-  byte trust_value;
-  char *trust_regexp;
-  u32 kid[2];
-};
-
-
-/*
- * Check whether the signature SIG is in the klist K.
- */
-static inline struct key_item *
-is_in_klist (struct key_item *k, PKT_signature *sig)
-{
-  for (; k; k = k->next)
-    {
-      if (k->kid[0] == sig->keyid[0] && k->kid[1] == sig->keyid[1])
-        return k;
-    }
-  return NULL;
-}
-
-
-
 /*-- trust.c --*/
 int cache_disabled_value (ctrl_t ctrl, PKT_public_key *pk);
 void register_trusted_keyid (u32 *keyid);
@@ -103,17 +73,6 @@ int get_validity_info (ctrl_t ctrl, kbnode_t kb, PKT_public_key *pk,
 const char *get_validity_string (ctrl_t ctrl,
                                  PKT_public_key *pk, PKT_user_id *uid);
 
-void mark_usable_uid_certs (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
-                            u32 *main_kid, struct key_item *klist,
-                            u32 curtime, u32 *next_expire);
-
-void clean_one_uid (ctrl_t ctrl, kbnode_t keyblock, kbnode_t uidnode,
-                    int noisy, int self_only,
-                    int *uids_cleaned, int *sigs_cleaned);
-void clean_key (ctrl_t ctrl, kbnode_t keyblock, int noisy, int self_only,
-                int *uids_cleaned,int *sigs_cleaned);
-
-
 
 /*-- trustdb.c --*/
 void tdb_register_trusted_keyid (u32 *keyid);