* main.h, seskey.c (encode_md_value): Modify to allow a q size greater
[gnupg.git] / g10 / export.c
index f982def..626b7d0 100644 (file)
@@ -1,5 +1,6 @@
 /* export.c
- * Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
+ * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004,
+ *               2005 Free Software Foundation, Inc.
  *
  * This file is part of GnuPG.
  *
@@ -15,7 +16,8 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
  */
 
 #include <config.h>
 #include "util.h"
 #include "main.h"
 #include "i18n.h"
+#include "trustdb.h"
+
+
+/* An object to keep track of subkeys. */
+struct subkey_list_s
+{
+  struct subkey_list_s *next;
+  u32 kid[2];
+};
+typedef struct subkey_list_s *subkey_list_t;
+
 
 static int do_export( STRLIST users, int secret, unsigned int options );
-static int do_export_stream( IOBUF out, STRLIST users,
-                            int secret, unsigned int options, int *any );
+static int do_export_stream( IOBUF out, STRLIST users, int secret,
+                            KBNODE *keyblock_out, unsigned int options,
+                            int *any );
 
 int
-parse_export_options(char *str,unsigned int *options)
+parse_export_options(char *str,unsigned int *options,int noisy)
 {
-  char *tok;
-  int hit=0;
-  struct
-  {
-    char *name;
-    unsigned int bit;
-  } export_opts[]=
+  struct parse_options export_opts[]=
     {
-      {"include-non-rfc",EXPORT_INCLUDE_NON_RFC},
-      {"include-local-sigs",EXPORT_INCLUDE_LOCAL_SIGS},
-      {"include-attributes",EXPORT_INCLUDE_ATTRIBUTES},
-      {"include-sensitive-revkeys",EXPORT_INCLUDE_SENSITIVE_REVKEYS},
-      {NULL,0}
+      {"export-local-sigs",EXPORT_LOCAL_SIGS,NULL,
+       N_("export signatures that are marked as local-only")},
+      {"export-attributes",EXPORT_ATTRIBUTES,NULL,
+       N_("export attribute user IDs (generally photo IDs)")},
+      {"export-sensitive-revkeys",EXPORT_SENSITIVE_REVKEYS,NULL,
+       N_("export revocation keys marked as \"sensitive\"")},
+      {"export-reset-subkey-passwd",EXPORT_RESET_SUBKEY_PASSWD,NULL,
+       N_("remove the passphrase from exported subkeys")},
+      {"export-clean",EXPORT_CLEAN,NULL,
+       N_("remove unusable parts from key during export")},
+      {"export-minimal",EXPORT_MINIMAL|EXPORT_CLEAN,NULL,
+       N_("remove as much as possible from key during export")},
+      /* Aliases for backward compatibility */
+      {"include-local-sigs",EXPORT_LOCAL_SIGS,NULL,NULL},
+      {"include-attributes",EXPORT_ATTRIBUTES,NULL,NULL},
+      {"include-sensitive-revkeys",EXPORT_SENSITIVE_REVKEYS,NULL,NULL},
+      /* dummy */
+      {"export-unusable-sigs",0,NULL,NULL},
+      {"export-clean-sigs",0,NULL,NULL},
+      {"export-clean-uids",0,NULL,NULL},
+      {NULL,0,NULL,NULL}
       /* add tags for include revoked and disabled? */
     };
 
-  while((tok=strsep(&str," ,")))
-    {
-      int i,rev=0;
-
-      if(ascii_memcasecmp("no-",tok,3)==0)
-       {
-         rev=1;
-         tok+=3;
-       }
-
-      for(i=0;export_opts[i].name;i++)
-       {
-         if(ascii_strcasecmp(export_opts[i].name,tok)==0)
-           {
-             if(rev)
-               *options&=~export_opts[i].bit;
-             else
-               *options|=export_opts[i].bit;
-             hit=1;
-             break;
-           }
-       }
-
-      if(!hit && !export_opts[i].name)
-       return 0;
-    }
-
-  return hit;
+  return parse_options(str,options,export_opts,noisy);
 }
 
+
 /****************
  * Export the public keys (to standard out or --output).
  * Depending on opt.armor the output is armored.
@@ -103,11 +101,12 @@ export_pubkeys( STRLIST users, unsigned int options )
  * been exported
  */
 int
-export_pubkeys_stream( IOBUF out, STRLIST users, unsigned int options )
+export_pubkeys_stream( IOBUF out, STRLIST users,
+                      KBNODE *keyblock_out, unsigned int options )
 {
     int any, rc;
 
-    rc = do_export_stream( out, users, 0, options, &any );
+    rc = do_export_stream( out, users, 0, keyblock_out, options, &any );
     if( !rc && !any )
        rc = -1;
     return rc;
@@ -144,10 +143,10 @@ do_export( STRLIST users, int secret, unsigned int options )
        afx.what = secret?5:1;
        iobuf_push_filter( out, armor_filter, &afx );
     }
-    if( opt.compress_keys && opt.compress )
-       iobuf_push_filter( out, compress_filter, &zfx );
-    rc = do_export_stream( out, users, secret, options, &any );
+    if( opt.compress_keys )
+      push_compress_filter(out,&zfx,default_compress_algo());
 
+    rc = do_export_stream( out, users, secret, NULL, options, &any );
     if( rc || !any )
        iobuf_cancel(out);
     else
@@ -156,16 +155,138 @@ do_export( STRLIST users, int secret, unsigned int options )
 }
 
 
+
+/* Release an entire subkey list. */
+static void
+release_subkey_list (subkey_list_t list)
+{
+  while (list)
+    {
+      subkey_list_t tmp = list->next;;
+      xfree (list);
+      list = tmp;
+    }
+}
+
+
+/* Returns true if NODE is a subkey and contained in LIST. */
+static int
+subkey_in_list_p (subkey_list_t list, KBNODE node)
+{
+  if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY
+      || node->pkt->pkttype == PKT_SECRET_SUBKEY )
+    {
+      u32 kid[2];
+
+      if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY)
+        keyid_from_pk (node->pkt->pkt.public_key, kid);
+      else
+        keyid_from_sk (node->pkt->pkt.secret_key, kid);
+      
+      for (; list; list = list->next)
+        if (list->kid[0] == kid[0] && list->kid[1] == kid[1])
+          return 1;
+    }
+  return 0;
+}
+
+/* Allocate a new subkey list item from NODE. */
+static subkey_list_t
+new_subkey_list_item (KBNODE node)
+{
+  subkey_list_t list = xcalloc (1, sizeof *list);
+
+  if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY)
+    keyid_from_pk (node->pkt->pkt.public_key, list->kid);
+  else if (node->pkt->pkttype == PKT_SECRET_SUBKEY)
+    keyid_from_sk (node->pkt->pkt.secret_key, list->kid);
+
+  return list;
+}
+
+
+/* Helper function to check whether the subkey at NODE actually
+   matches the description at DESC.  The function returns true if the
+   key under question has been specified by an exact specification
+   (keyID or fingerprint) and does match the one at NODE.  It is
+   assumed that the packet at NODE is either a public or secret
+   subkey. */
+static int
+exact_subkey_match_p (KEYDB_SEARCH_DESC *desc, KBNODE node)
+{
+  u32 kid[2];
+  byte fpr[MAX_FINGERPRINT_LEN];
+  size_t fprlen;
+  int result = 0;
+
+  switch(desc->mode)
+    {
+    case KEYDB_SEARCH_MODE_SHORT_KID:
+    case KEYDB_SEARCH_MODE_LONG_KID:
+      if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY)
+        keyid_from_pk (node->pkt->pkt.public_key, kid);
+      else
+        keyid_from_sk (node->pkt->pkt.secret_key, kid);
+      break;
+      
+    case KEYDB_SEARCH_MODE_FPR16:
+    case KEYDB_SEARCH_MODE_FPR20:
+    case KEYDB_SEARCH_MODE_FPR:
+      if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY)
+        fingerprint_from_pk (node->pkt->pkt.public_key, fpr,&fprlen);
+      else
+        fingerprint_from_sk (node->pkt->pkt.secret_key, fpr,&fprlen);
+      break;
+      
+    default:
+      break;
+    }
+  
+  switch(desc->mode)
+    {
+    case KEYDB_SEARCH_MODE_SHORT_KID:
+      if (desc->u.kid[1] == kid[1])
+        result = 1;
+      break;
+
+    case KEYDB_SEARCH_MODE_LONG_KID:
+      if (desc->u.kid[0] == kid[0] && desc->u.kid[1] == kid[1])
+        result = 1;
+      break;
+
+    case KEYDB_SEARCH_MODE_FPR16:
+      if (!memcmp (desc->u.fpr, fpr, 16))
+        result = 1;
+      break;
+
+    case KEYDB_SEARCH_MODE_FPR20:
+    case KEYDB_SEARCH_MODE_FPR:
+      if (!memcmp (desc->u.fpr, fpr, 20))
+        result = 1;
+      break;
+
+    default:
+      break;
+    }
+
+  return result;
+}
+
+
+/* If keyblock_out is non-NULL, AND the exit code is zero, then it
+   contains a pointer to the first keyblock found and exported.  No
+   other keyblocks are exported.  The caller must free it. */
 static int
 do_export_stream( IOBUF out, STRLIST users, int secret,
-                 unsigned int options, int *any )
+                 KBNODE *keyblock_out, unsigned int options, int *any )
 {
     int rc = 0;
     PACKET pkt;
     KBNODE keyblock = NULL;
     KBNODE kbctx, node;
-    int ndesc;
+    size_t ndesc, descindex;
     KEYDB_SEARCH_DESC *desc = NULL;
+    subkey_list_t subkey_list = NULL;  /* Track alreay processed subkeys. */
     KEYDB_HANDLE kdbhd;
     STRLIST sl;
 
@@ -175,23 +296,23 @@ do_export_stream( IOBUF out, STRLIST users, int secret,
 
     if (!users) {
         ndesc = 1;
-        desc = m_alloc_clear ( ndesc * sizeof *desc);
+        desc = xcalloc ( ndesc, sizeof *desc );
         desc[0].mode = KEYDB_SEARCH_MODE_FIRST;
     }
     else {
         for (ndesc=0, sl=users; sl; sl = sl->next, ndesc++) 
             ;
-        desc = m_alloc ( ndesc * sizeof *desc);
+        desc = xmalloc ( ndesc * sizeof *desc);
         
         for (ndesc=0, sl=users; sl; sl = sl->next) {
            if (classify_user_id (sl->d, desc+ndesc))
                 ndesc++;
             else
-                log_error (_("key `%s' not found: %s\n"),
+                log_error (_("key \"%s\" not found: %s\n"),
                            sl->d, g10_errstr (G10ERR_INV_USER_ID));
         }
 
-        /* it would be nice to see which of the given users did
+        /* It would be nice to see which of the given users did
            actually match one in the keyring.  To implement this we
            need to have a found flag for each entry in desc and to set
            this we must check all those entries after a match to mark
@@ -199,95 +320,170 @@ do_export_stream( IOBUF out, STRLIST users, int secret,
            do this we need an extra flag to enable this feature so */
     }
 
+#ifdef ENABLE_SELINUX_HACKS
+    if (secret) {
+        log_error (_("exporting secret keys not allowed\n"));
+        rc = G10ERR_GENERAL;
+        goto leave;
+    }
+#endif
 
-    while (!(rc = keydb_search (kdbhd, desc, ndesc))) {
-        int sha1_warned=0;
+    while (!(rc = keydb_search2 (kdbhd, desc, ndesc, &descindex))) {
+        int sha1_warned=0,skip_until_subkey=0;
        u32 sk_keyid[2];
 
        if (!users) 
             desc[0].mode = KEYDB_SEARCH_MODE_NEXT;
 
-        /* read the keyblock */
+        /* Read the keyblock. */
         rc = keydb_get_keyblock (kdbhd, &keyblock );
        if( rc ) {
             log_error (_("error reading keyblock: %s\n"), g10_errstr(rc) );
            goto leave;
        }
 
-       /* do not export keys which are incompatible with rfc2440 */
-       if( !(options&EXPORT_INCLUDE_NON_RFC) &&
-           (node = find_kbnode( keyblock, PKT_PUBLIC_KEY )) ) {
-           PKT_public_key *pk = node->pkt->pkt.public_key;
-           if( pk->version == 3 && pk->pubkey_algo > 3 ) {
-               log_info(_("key %08lX: not a rfc2440 key - skipped\n"),
-                             (ulong)keyid_from_pk( pk, NULL) );
-               continue;
-           }
-       }
-
-       node=find_kbnode( keyblock, PKT_SECRET_KEY );
-       if(node)
+       if((node=find_kbnode(keyblock,PKT_SECRET_KEY)))
          {
            PKT_secret_key *sk=node->pkt->pkt.secret_key;
 
            keyid_from_sk(sk,sk_keyid);
 
-           /* we can't apply GNU mode 1001 on an unprotected key */
+           /* We can't apply GNU mode 1001 on an unprotected key. */
            if( secret == 2 && !sk->is_protected )
              {
-               log_info(_("key %08lX: not protected - skipped\n"),
-                        (ulong)sk_keyid[1]);
+               log_info(_("key %s: not protected - skipped\n"),
+                        keystr(sk_keyid));
                continue;
              }
 
-           /* no v3 keys with GNU mode 1001 */
+           /* No v3 keys with GNU mode 1001. */
            if( secret == 2 && sk->version == 3 )
              {
-               log_info(_("key %08lX: PGP 2.x style key - skipped\n"),
-                        (ulong)sk_keyid[1]);
+               log_info(_("key %s: PGP 2.x style key - skipped\n"),
+                        keystr(sk_keyid));
                continue;
              }
+
+            /* It does not make sense to export a key with a primary
+               key on card using a non-key stub.  We simply skip those
+               keys when used with --export-secret-subkeys. */
+            if (secret == 2 && sk->is_protected
+                && sk->protect.s2k.mode == 1002 ) 
+              {
+               log_info(_("key %s: key material on-card - skipped\n"),
+                        keystr(sk_keyid));
+               continue;
+              }
+         }
+       else
+         {
+           /* It's a public key export, so do the cleaning if
+              requested.  Note that both export-clean and
+              export-minimal only apply to UID sigs (0x10, 0x11,
+              0x12, and 0x13).  A designated revocation is never
+              stripped, even with export-minimal set. */
+
+           if(options&EXPORT_CLEAN)
+             clean_key(keyblock,opt.verbose,options&EXPORT_MINIMAL,NULL,NULL);
          }
 
-       /* and write it */
+       /* And write it. */
        for( kbctx=NULL; (node = walk_kbnode( keyblock, &kbctx, 0 )); ) {
-           /* don't export any comment packets but those in the
-            * secret keyring */
-           if( !secret && node->pkt->pkttype == PKT_COMMENT )
-               continue;
-            /* make sure that ring_trust packets never get exported */
+           if( skip_until_subkey )
+             {
+               if(node->pkt->pkttype==PKT_PUBLIC_SUBKEY
+                  || node->pkt->pkttype==PKT_SECRET_SUBKEY)
+                 skip_until_subkey=0;
+               else
+                 continue;
+             }
+
+           /* We used to use comment packets, but not any longer.  In
+              case we still have comments on a key, strip them here
+              before we call build_packet(). */
+           if( node->pkt->pkttype == PKT_COMMENT )
+             continue;
+
+            /* Make sure that ring_trust packets never get exported. */
             if (node->pkt->pkttype == PKT_RING_TRUST)
               continue;
 
-           if( node->pkt->pkttype == PKT_SIGNATURE ) {
-             /* do not export packets which are marked as not exportable */
-             if( !(options&EXPORT_INCLUDE_LOCAL_SIGS) &&
-                 !node->pkt->pkt.signature->flags.exportable )
-               continue; /* not exportable */
-
-             /* do not export packets with a "sensitive" revocation
-                 key.  This will need revisiting when we start
-                 supporting creating revocation keys and not just
-                 reading them. */
-             if( !(options&EXPORT_INCLUDE_SENSITIVE_REVKEYS) &&
-                 node->pkt->pkt.signature->revkey ) {
-               int i;
-
-               for(i=0;i<node->pkt->pkt.signature->numrevkeys;i++)
-                 if(node->pkt->pkt.signature->revkey[i]->class & 0x40)
-                   break;
-
-               if(i<node->pkt->pkt.signature->numrevkeys)
+           /* If exact is set, then we only export what was requested
+              (plus the primary key, if the user didn't specifically
+              request it). */
+           if(desc[descindex].exact
+              && (node->pkt->pkttype==PKT_PUBLIC_SUBKEY
+                  || node->pkt->pkttype==PKT_SECRET_SUBKEY))
+             {
+                if (!exact_subkey_match_p (desc+descindex, node))
+                  {
+                    /* Before skipping this subkey, check whether any
+                       other description wants an exact match on a
+                       subkey and include that subkey into the output
+                       too.  Need to add this subkey to a list so that
+                       it won't get processed a second time.
+                   
+                       So the first step here is to check that list and
+                       skip in any case if the key is in that list.
+
+                       We need this whole mess because the import
+                       function is not able to merge secret keys and
+                       thus it is useless to output them as two
+                       separate keys and have import merge them.  */
+                    if (subkey_in_list_p (subkey_list, node))  
+                      skip_until_subkey = 1; /* Already processed this one. */
+                    else
+                      {
+                        size_t j;
+
+                        for (j=0; j < ndesc; j++)
+                          if (j != descindex && desc[j].exact
+                              && exact_subkey_match_p (desc+j, node))
+                            break;
+                        if (!(j < ndesc))
+                          skip_until_subkey = 1; /* No other one matching. */ 
+                      }
+                  }
+
+               if(skip_until_subkey)
                  continue;
+
+                /* Mark this one as processed. */
+                {
+                  subkey_list_t tmp = new_subkey_list_item (node);
+                  tmp->next = subkey_list;
+                  subkey_list = tmp;
+                }
              }
 
-             /* delete our verification cache */
-             delete_sig_subpkt (node->pkt->pkt.signature->unhashed,
-                                SIGSUBPKT_PRIV_VERIFY_CACHE);
-           }
+           if(node->pkt->pkttype==PKT_SIGNATURE)
+             {
+               /* do not export packets which are marked as not
+                  exportable */
+               if(!(options&EXPORT_LOCAL_SIGS)
+                  && !node->pkt->pkt.signature->flags.exportable)
+                 continue; /* not exportable */
+
+               /* Do not export packets with a "sensitive" revocation
+                  key unless the user wants us to.  Note that we do
+                  export these when issuing the actual revocation
+                  (see revoke.c). */
+               if(!(options&EXPORT_SENSITIVE_REVKEYS)
+                  && node->pkt->pkt.signature->revkey)
+                 {
+                   int i;
+
+                   for(i=0;i<node->pkt->pkt.signature->numrevkeys;i++)
+                     if(node->pkt->pkt.signature->revkey[i]->class & 0x40)
+                       break;
+
+                   if(i<node->pkt->pkt.signature->numrevkeys)
+                     continue;
+                 }
+             }
 
            /* Don't export attribs? */
-           if( !(options&EXPORT_INCLUDE_ATTRIBUTES) &&
+           if( !(options&EXPORT_ATTRIBUTES) &&
                node->pkt->pkttype == PKT_USER_ID &&
                node->pkt->pkt.user_id->attrib_data ) {
              /* Skip until we get to something that is not an attrib
@@ -299,33 +495,81 @@ do_export_stream( IOBUF out, STRLIST users, int secret,
              continue;
            }
 
-           if( secret == 2 && node->pkt->pkttype == PKT_SECRET_KEY ) {
-               /* we don't want to export the secret parts of the
+           if( secret == 2 && node->pkt->pkttype == PKT_SECRET_KEY )
+             {
+               /* We don't want to export the secret parts of the
                 * primary key, this is done by using GNU protection mode 1001
                 */
                int save_mode = node->pkt->pkt.secret_key->protect.s2k.mode;
                node->pkt->pkt.secret_key->protect.s2k.mode = 1001;
                rc = build_packet( out, node->pkt );
                node->pkt->pkt.secret_key->protect.s2k.mode = save_mode;
-           }
-           else {
-             /* Warn the user if the secret key or any of the secret
-                 subkeys are protected with SHA1 and we have
-                 simple_sk_checksum set. */
-             if(!sha1_warned && opt.simple_sk_checksum &&
-                (node->pkt->pkttype==PKT_SECRET_KEY ||
-                 node->pkt->pkttype==PKT_SECRET_SUBKEY) &&
-                node->pkt->pkt.secret_key->protect.sha1chk)
-               {
-                 /* I hope this warning doesn't confuse people. */
-                 log_info("WARNING: secret key %08lX does not have a "
-                          "simple SK checksum\n",(ulong)sk_keyid[1]);
-
-                 sha1_warned=1;
-               }
+             }
+           else if (secret == 2 && node->pkt->pkttype == PKT_SECRET_SUBKEY
+                     && (opt.export_options&EXPORT_RESET_SUBKEY_PASSWD))
+              {
+                /* If the subkey is protected reset the passphrase to
+                   export an unprotected subkey.  This feature is
+                   useful in cases of a subkey copied to an unattended
+                   machine where a passphrase is not required. */
+                PKT_secret_key *sk_save, *sk;
+
+                sk_save = node->pkt->pkt.secret_key;
+                sk = copy_secret_key (NULL, sk_save);
+                node->pkt->pkt.secret_key = sk;
+
+                log_info (_("about to export an unprotected subkey\n"));
+                switch (is_secret_key_protected (sk))
+                  {
+                  case -1:
+                    rc = G10ERR_PUBKEY_ALGO;
+                    break;
+                  case 0:
+                    break;
+                  default:
+                    if (sk->protect.s2k.mode == 1001)
+                      ; /* No secret parts. */
+                    else if( sk->protect.s2k.mode == 1002 ) 
+                      ; /* Card key stub. */
+                    else 
+                      {
+                        rc = check_secret_key( sk, 0 );
+                      }
+                    break;
+                  }
+                if (rc)
+                  {
+                    node->pkt->pkt.secret_key = sk_save;
+                    free_secret_key (sk);
+                    log_error (_("failed to unprotect the subkey: %s\n"),
+                               g10_errstr (rc));
+                    goto leave;
+                  }
+
+               rc = build_packet (out, node->pkt);
+
+                node->pkt->pkt.secret_key = sk_save;
+                free_secret_key (sk);
+              }
+           else
+             {
+               /* Warn the user if the secret key or any of the secret
+                  subkeys are protected with SHA1 and we have
+                  simple_sk_checksum set. */
+               if(!sha1_warned && opt.simple_sk_checksum &&
+                  (node->pkt->pkttype==PKT_SECRET_KEY ||
+                   node->pkt->pkttype==PKT_SECRET_SUBKEY) &&
+                  node->pkt->pkt.secret_key->protect.sha1chk)
+                 {
+                   /* I hope this warning doesn't confuse people. */
+                   log_info(_("WARNING: secret key %s does not have a "
+                              "simple SK checksum\n"),keystr(sk_keyid));
+
+                   sha1_warned=1;
+                 }
 
                rc = build_packet( out, node->pkt );
-           }
+             }
 
            if( rc ) {
                log_error("build_packet(%d) failed: %s\n",
@@ -335,16 +579,22 @@ do_export_stream( IOBUF out, STRLIST users, int secret,
            }
        }
        ++*any;
+       if(keyblock_out)
+         {
+           *keyblock_out=keyblock;
+           break;
+         }
     }
     if( rc == -1 )
        rc = 0;
 
   leave:
-    m_free(desc);
+    release_subkey_list (subkey_list);
+    xfree(desc);
     keydb_release (kdbhd);
-    release_kbnode( keyblock );
+    if(rc || keyblock_out==NULL)
+      release_kbnode( keyblock );
     if( !*any )
        log_info(_("WARNING: nothing exported\n"));
     return rc;
 }
-