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-rw-r--r--g13/create.c303
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diff --git a/g13/create.c b/g13/create.c
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+/* create.c - Create a new crypto container
+ * Copyright (C) 2009 Free Software Foundation, Inc.
+ *
+ * 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/>.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <assert.h>
+
+#include "g13.h"
+#include "../common/i18n.h"
+#include "create.h"
+
+#include "keyblob.h"
+#include "backend.h"
+#include "g13tuple.h"
+#include "../common/sysutils.h"
+#include "../common/call-gpg.h"
+
+/* Create a new blob with all the session keys and other meta
+ information which are to be stored encrypted in the crypto
+ container header. On success the malloced blob is stored at R_BLOB
+ and its length at R_BLOBLEN. On error an error code is returned
+ and (R_BLOB,R_BLOBLEN) are set to (NULL,0).
+
+ The format of this blob is a sequence of tag-length-value tuples.
+ All tuples have this format:
+
+ 2 byte TAG Big endian unsigned integer (0..65535)
+ described by the KEYBLOB_TAG_ constants.
+ 2 byte LENGTH Big endian unsigned integer (0..65535)
+ giving the length of the value.
+ length bytes VALUE The value described by the tag.
+
+ The first tag in a keyblob must be a BLOBVERSION. The other tags
+ depend on the type of the container as described by the CONTTYPE
+ tag. See keyblob.h for details. */
+static gpg_error_t
+create_new_keyblob (ctrl_t ctrl, int is_detached,
+ void **r_blob, size_t *r_bloblen)
+{
+ gpg_error_t err;
+ unsigned char twobyte[2];
+ membuf_t mb;
+
+ *r_blob = NULL;
+ *r_bloblen = 0;
+
+ init_membuf_secure (&mb, 512);
+
+ append_tuple (&mb, KEYBLOB_TAG_BLOBVERSION, "\x01", 1);
+
+ twobyte[0] = (ctrl->conttype >> 8);
+ twobyte[1] = (ctrl->conttype);
+ append_tuple (&mb, KEYBLOB_TAG_CONTTYPE, twobyte, 2);
+ if (is_detached)
+ append_tuple (&mb, KEYBLOB_TAG_DETACHED, NULL, 0);
+
+ err = be_create_new_keys (ctrl->conttype, &mb);
+ if (err)
+ goto leave;
+
+ /* Just for testing. */
+ append_tuple (&mb, KEYBLOB_TAG_FILLER, "filler", 6);
+
+ *r_blob = get_membuf (&mb, r_bloblen);
+ if (!*r_blob)
+ {
+ err = gpg_error_from_syserror ();
+ *r_bloblen = 0;
+ }
+ else
+ log_debug ("used keyblob size is %zu\n", *r_bloblen);
+
+ leave:
+ xfree (get_membuf (&mb, NULL));
+ return err;
+}
+
+
+
+/* Encrypt the keyblob (KEYBLOB,KEYBLOBLEN) and store the result at
+ (R_ENCBLOB, R_ENCBLOBLEN). Returns 0 on success or an error code.
+ On error R_EKYBLOB is set to NULL. Depending on the keys set in
+ CTRL the result is a single OpenPGP binary message, a single
+ special OpenPGP packet encapsulating a CMS message or a
+ concatenation of both with the CMS packet being the last. */
+gpg_error_t
+g13_encrypt_keyblob (ctrl_t ctrl, void *keyblob, size_t keybloblen,
+ void **r_encblob, size_t *r_encbloblen)
+{
+ gpg_error_t err;
+
+ /* FIXME: For now we only implement OpenPGP. */
+ err = gpg_encrypt_blob (ctrl, opt.gpg_program, opt.gpg_arguments,
+ keyblob, keybloblen,
+ ctrl->recipients,
+ r_encblob, r_encbloblen);
+
+ return err;
+}
+
+
+/* Write a new file under the name FILENAME with the keyblob and an
+ appropriate header. This function is called with a lock file in
+ place and after checking that the filename does not exists. */
+static gpg_error_t
+write_keyblob (const char *filename,
+ const void *keyblob, size_t keybloblen)
+{
+ gpg_error_t err;
+ estream_t fp;
+ unsigned char packet[32];
+ size_t headerlen, paddinglen;
+
+ fp = es_fopen (filename, "wbx");
+ if (!fp)
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error creating new container '%s': %s\n",
+ filename, gpg_strerror (err));
+ return err;
+ }
+
+ /* Allow for an least 8 times larger keyblob to accommodate for
+ future key changes. Round it up to 4096 byte. */
+ headerlen = ((32 + 8 * keybloblen + 16) + 4095) / 4096 * 4096;
+ paddinglen = headerlen - 32 - keybloblen;
+ assert (paddinglen >= 16);
+
+ packet[0] = (0xc0|61); /* CTB for the private packet type 0x61. */
+ packet[1] = 0xff; /* 5 byte length packet, value 20. */
+ packet[2] = 0;
+ packet[3] = 0;
+ packet[4] = 0;
+ packet[5] = 26;
+ memcpy (packet+6, "GnuPG/G13", 10); /* Packet subtype. */
+ packet[16] = 1; /* G13 packet format version. */
+ packet[17] = 0; /* Reserved. */
+ packet[18] = 0; /* Reserved. */
+ packet[19] = 0; /* OS Flag. */
+ packet[20] = (headerlen >> 24); /* Total length of header. */
+ packet[21] = (headerlen >> 16);
+ packet[22] = (headerlen >> 8);
+ packet[23] = (headerlen);
+ packet[24] = 1; /* Number of header copies. */
+ packet[25] = 0; /* Number of header copies at the end. */
+ packet[26] = 0; /* Reserved. */
+ packet[27] = 0; /* Reserved. */
+ packet[28] = 0; /* Reserved. */
+ packet[29] = 0; /* Reserved. */
+ packet[30] = 0; /* Reserved. */
+ packet[31] = 0; /* Reserved. */
+
+ if (es_fwrite (packet, 32, 1, fp) != 1)
+ goto writeerr;
+
+ if (es_fwrite (keyblob, keybloblen, 1, fp) != 1)
+ goto writeerr;
+
+ /* Write the padding. */
+ packet[0] = (0xc0|61); /* CTB for Private packet type 0x61. */
+ packet[1] = 0xff; /* 5 byte length packet, value 20. */
+ packet[2] = (paddinglen-6) >> 24;
+ packet[3] = (paddinglen-6) >> 16;
+ packet[4] = (paddinglen-6) >> 8;
+ packet[5] = (paddinglen-6);
+ memcpy (packet+6, "GnuPG/PAD", 10); /* Packet subtype. */
+ if (es_fwrite (packet, 16, 1, fp) != 1)
+ goto writeerr;
+ memset (packet, 0, 32);
+ for (paddinglen-=16; paddinglen >= 32; paddinglen -= 32)
+ if (es_fwrite (packet, 32, 1, fp) != 1)
+ goto writeerr;
+ if (paddinglen)
+ if (es_fwrite (packet, paddinglen, 1, fp) != 1)
+ goto writeerr;
+
+ if (es_fclose (fp))
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error closing '%s': %s\n",
+ filename, gpg_strerror (err));
+ remove (filename);
+ return err;
+ }
+
+ return 0;
+
+
+ writeerr:
+ err = gpg_error_from_syserror ();
+ log_error ("error writing header to '%s': %s\n",
+ filename, gpg_strerror (err));
+ es_fclose (fp);
+ remove (filename);
+ return err;
+}
+
+
+
+/* Create a new container under the name FILENAME and initialize it
+ using the current settings. If the file already exists an error is
+ returned. */
+gpg_error_t
+g13_create_container (ctrl_t ctrl, const char *filename)
+{
+ gpg_error_t err;
+ dotlock_t lock;
+ void *keyblob = NULL;
+ size_t keybloblen;
+ void *enckeyblob = NULL;
+ size_t enckeybloblen;
+ char *detachedname = NULL;
+ int detachedisdir;
+ tupledesc_t tuples = NULL;
+ unsigned int dummy_rid;
+
+ if (!ctrl->recipients)
+ return gpg_error (GPG_ERR_NO_PUBKEY);
+
+ err = be_take_lock_for_create (ctrl, filename, &lock);
+ if (err)
+ goto leave;
+
+ /* And a possible detached file or directory may not exist either. */
+ err = be_get_detached_name (ctrl->conttype, filename,
+ &detachedname, &detachedisdir);
+ if (err)
+ goto leave;
+ if (detachedname)
+ {
+ struct stat sb;
+
+ if (!gnupg_stat (detachedname, &sb))
+ {
+ err = gpg_error (GPG_ERR_EEXIST);
+ goto leave;
+ }
+ }
+
+ if (ctrl->conttype != CONTTYPE_DM_CRYPT)
+ {
+ /* Create a new keyblob. */
+ err = create_new_keyblob (ctrl, !!detachedname, &keyblob, &keybloblen);
+ if (err)
+ goto leave;
+
+ /* Encrypt that keyblob. */
+ err = g13_encrypt_keyblob (ctrl, keyblob, keybloblen,
+ &enckeyblob, &enckeybloblen);
+ if (err)
+ goto leave;
+
+ /* Put a copy of the keyblob into a tuple structure. */
+ err = create_tupledesc (&tuples, keyblob, keybloblen);
+ if (err)
+ goto leave;
+ keyblob = NULL;
+ /* if (opt.verbose) */
+ /* dump_keyblob (tuples); */
+
+ /* Write out the header, the encrypted keyblob and some padding. */
+ err = write_keyblob (filename, enckeyblob, enckeybloblen);
+ if (err)
+ goto leave;
+ }
+
+ /* Create and append the container. FIXME: We should pass the
+ estream object in addition to the filename, so that the backend
+ can append the container to the g13 file. */
+ err = be_create_container (ctrl, ctrl->conttype, filename, -1, tuples,
+ &dummy_rid);
+
+
+ leave:
+ destroy_tupledesc (tuples);
+ xfree (detachedname);
+ xfree (enckeyblob);
+ xfree (keyblob);
+ dotlock_destroy (lock);
+
+ return err;
+}
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