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387ee7dcbd
* common/b64dec.c (b64decode): Move to ... * common/miscellaneous.c: here. * common/t-b64.c: Re-inroduce and keep only the b64decode test code.
864 lines
23 KiB
C
864 lines
23 KiB
C
/* encrypt.c - Encrypt a message
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* Copyright (C) 2001, 2003, 2004, 2007, 2008,
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* 2010 Free Software Foundation, Inc.
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* Copyright (C) 2001-2019 Werner Koch
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* Copyright (C) 2015-2020 g10 Code GmbH
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*
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* This file is part of GnuPG.
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*
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* GnuPG is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or
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* (at your option) any later version.
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*
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* GnuPG is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <https://www.gnu.org/licenses/>.
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* SPDX-License-Identifier: GPL-3.0-or-later
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*/
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#include <config.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <errno.h>
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#include <unistd.h>
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#include <time.h>
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#include "gpgsm.h"
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#include <gcrypt.h>
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#include <ksba.h>
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#include "keydb.h"
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#include "../common/i18n.h"
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#include "../common/compliance.h"
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struct dek_s {
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const char *algoid;
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int algo;
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gcry_cipher_hd_t chd;
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char key[32];
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int keylen;
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char iv[32];
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int ivlen;
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};
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typedef struct dek_s *DEK;
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/* Callback parameters for the encryption. */
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struct encrypt_cb_parm_s
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{
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estream_t fp;
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DEK dek;
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int eof_seen;
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int ready;
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int readerror;
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int bufsize;
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unsigned char *buffer;
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int buflen;
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};
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/* Initialize the data encryption key (session key). */
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static int
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init_dek (DEK dek)
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{
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int rc=0, mode, i;
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dek->algo = gcry_cipher_map_name (dek->algoid);
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mode = gcry_cipher_mode_from_oid (dek->algoid);
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if (!dek->algo || !mode)
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{
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log_error ("unsupported algorithm '%s'\n", dek->algoid);
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return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
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}
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/* Extra check for algorithms we consider to be too weak for
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encryption, although we support them for decryption. Note that
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there is another check below discriminating on the key length. */
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switch (dek->algo)
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{
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case GCRY_CIPHER_DES:
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case GCRY_CIPHER_RFC2268_40:
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log_error ("cipher algorithm '%s' not allowed: too weak\n",
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gnupg_cipher_algo_name (dek->algo));
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return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
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default:
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break;
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}
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dek->keylen = gcry_cipher_get_algo_keylen (dek->algo);
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if (!dek->keylen || dek->keylen > sizeof (dek->key))
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return gpg_error (GPG_ERR_BUG);
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dek->ivlen = gcry_cipher_get_algo_blklen (dek->algo);
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if (!dek->ivlen || dek->ivlen > sizeof (dek->iv))
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return gpg_error (GPG_ERR_BUG);
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/* Make sure we don't use weak keys. */
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if (dek->keylen < 100/8)
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{
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log_error ("key length of '%s' too small\n", dek->algoid);
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return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
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}
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rc = gcry_cipher_open (&dek->chd, dek->algo, mode, GCRY_CIPHER_SECURE);
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if (rc)
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{
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log_error ("failed to create cipher context: %s\n", gpg_strerror (rc));
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return rc;
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}
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for (i=0; i < 8; i++)
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{
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gcry_randomize (dek->key, dek->keylen, GCRY_STRONG_RANDOM );
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rc = gcry_cipher_setkey (dek->chd, dek->key, dek->keylen);
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if (gpg_err_code (rc) != GPG_ERR_WEAK_KEY)
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break;
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log_info(_("weak key created - retrying\n") );
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}
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if (rc)
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{
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log_error ("failed to set the key: %s\n", gpg_strerror (rc));
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gcry_cipher_close (dek->chd);
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dek->chd = NULL;
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return rc;
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}
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gcry_create_nonce (dek->iv, dek->ivlen);
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rc = gcry_cipher_setiv (dek->chd, dek->iv, dek->ivlen);
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if (rc)
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{
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log_error ("failed to set the IV: %s\n", gpg_strerror (rc));
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gcry_cipher_close (dek->chd);
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dek->chd = NULL;
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return rc;
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}
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return 0;
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}
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/* Encode an RSA session key. */
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static int
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encode_session_key (DEK dek, gcry_sexp_t * r_data)
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{
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gcry_sexp_t data;
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char *p;
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int rc;
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p = xtrymalloc (64 + 2 * dek->keylen);
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if (!p)
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return gpg_error_from_syserror ();
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strcpy (p, "(data\n (flags pkcs1)\n (value #");
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bin2hex (dek->key, dek->keylen, p + strlen (p));
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strcat (p, "#))\n");
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rc = gcry_sexp_sscan (&data, NULL, p, strlen (p));
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xfree (p);
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*r_data = data;
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return rc;
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}
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/* Encrypt DEK using ECDH. S_PKEY is the public key. On success the
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* result is stored at R_ENCVAL. Example of a public key:
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*
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* (public-key (ecc (curve "1.3.132.0.34") (q #04B0[...]B8#)))
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*
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*/
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static gpg_error_t
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ecdh_encrypt (DEK dek, gcry_sexp_t s_pkey, gcry_sexp_t *r_encval)
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{
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gpg_error_t err;
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gcry_sexp_t l1;
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char *curvebuf = NULL;
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const char *curve;
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unsigned int curvebits;
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const char *encr_algo_str;
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const char *wrap_algo_str;
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int hash_algo, cipher_algo;
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unsigned int keylen;
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unsigned char key[32];
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gcry_sexp_t s_data = NULL;
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gcry_sexp_t s_encr = NULL;
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gcry_buffer_t ioarray[2] = { {0}, {0} };
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unsigned char *secret; /* Alias for ioarray[0]. */
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unsigned int secretlen;
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unsigned char *pubkey; /* Alias for ioarray[1]. */
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unsigned int pubkeylen;
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gcry_cipher_hd_t cipher_hd = NULL;
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unsigned char *result = NULL;
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unsigned int resultlen;
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*r_encval = NULL;
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/* Figure out the encryption and wrap algo OIDs. */
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/* Get the curve name if any, */
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l1 = gcry_sexp_find_token (s_pkey, "curve", 0);
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if (l1)
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{
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curvebuf = gcry_sexp_nth_string (l1, 1);
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gcry_sexp_release (l1);
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}
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if (!curvebuf)
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{
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err = gpg_error (GPG_ERR_INV_CURVE);
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log_error ("%s: invalid public key: no curve\n", __func__);
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goto leave;
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}
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/* We need to use our OpenPGP mapping to turn a curve name into its
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* canonical numerical OID. We also use this to get the size of the
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* curve which we need to figure out a suitable hash algo. We
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* should have a Libgcrypt function to do this; see bug report #4926. */
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curve = openpgp_curve_to_oid (curvebuf, &curvebits, NULL);
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if (!curve)
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{
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err = gpg_error (GPG_ERR_UNKNOWN_CURVE);
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log_error ("%s: invalid public key: %s\n", __func__, gpg_strerror (err));
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goto leave;
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}
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xfree (curvebuf);
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curvebuf = NULL;
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/* Our mapping matches the recommended algorithms from RFC-5753 but
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* not supporting the short curves which would require 3DES. */
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if (curvebits < 255)
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{
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err = gpg_error (GPG_ERR_UNKNOWN_CURVE);
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log_error ("%s: curve '%s' is not supported\n", __func__, curve);
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goto leave;
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}
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else if (opt.force_ecdh_sha1kdf)
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{
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/* dhSinglePass-stdDH-sha1kdf-scheme */
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encr_algo_str = "1.3.133.16.840.63.0.2";
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wrap_algo_str = "2.16.840.1.101.3.4.1.45";
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hash_algo = GCRY_MD_SHA1;
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cipher_algo = GCRY_CIPHER_AES256;
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keylen = 32;
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}
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else if (curvebits <= 256)
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{
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/* dhSinglePass-stdDH-sha256kdf-scheme */
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encr_algo_str = "1.3.132.1.11.1";
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wrap_algo_str = "2.16.840.1.101.3.4.1.5";
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hash_algo = GCRY_MD_SHA256;
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cipher_algo = GCRY_CIPHER_AES128;
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keylen = 16;
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}
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else if (curvebits <= 384)
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{
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/* dhSinglePass-stdDH-sha384kdf-scheme */
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encr_algo_str = "1.3.132.1.11.2";
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wrap_algo_str = "2.16.840.1.101.3.4.1.25";
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hash_algo = GCRY_MD_SHA384;
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cipher_algo = GCRY_CIPHER_AES256;
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keylen = 24;
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}
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else
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{
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/* dhSinglePass-stdDH-sha512kdf-scheme*/
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encr_algo_str = "1.3.132.1.11.3";
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wrap_algo_str = "2.16.840.1.101.3.4.1.45";
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hash_algo = GCRY_MD_SHA512;
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cipher_algo = GCRY_CIPHER_AES256;
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keylen = 32;
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}
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/* Create a secret and an ephemeral key. */
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{
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char *k;
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k = gcry_random_bytes_secure ((curvebits+7)/8, GCRY_STRONG_RANDOM);
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if (DBG_CRYPTO)
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log_printhex (k, (curvebits+7)/8, "ephm. k .:");
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err = gcry_sexp_build (&s_data, NULL, "%b", (int)(curvebits+7)/8, k);
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xfree (k);
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}
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if (err)
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{
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log_error ("%s: error building ephemeral secret: %s\n",
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__func__, gpg_strerror (err));
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goto leave;
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}
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err = gcry_pk_encrypt (&s_encr, s_data, s_pkey);
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if (err)
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{
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log_error ("%s: error encrypting ephemeral secret: %s\n",
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__func__, gpg_strerror (err));
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goto leave;
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}
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err = gcry_sexp_extract_param (s_encr, NULL, "&se",
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&ioarray+0, ioarray+1, NULL);
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if (err)
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{
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log_error ("%s: error extracting ephemeral key and secret: %s\n",
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__func__, gpg_strerror (err));
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goto leave;
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}
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secret = ioarray[0].data;
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secretlen = ioarray[0].len;
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pubkey = ioarray[1].data;
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pubkeylen = ioarray[1].len;
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if (DBG_CRYPTO)
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{
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log_printhex (pubkey, pubkeylen, "pubkey ..:");
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log_printhex (secret, secretlen, "secret ..:");
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}
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/* Extract X coordinate from SECRET. */
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if (secretlen < 5) /* 5 because N could be reduced to (n-1)/2. */
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err = gpg_error (GPG_ERR_BAD_DATA);
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else if (*secret == 0x04)
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{
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secretlen--;
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memmove (secret, secret+1, secretlen);
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if ((secretlen & 1))
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{
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err = gpg_error (GPG_ERR_BAD_DATA);
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goto leave;
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}
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secretlen /= 2;
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}
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else if (*secret == 0x40 || *secret == 0x41)
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{
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secretlen--;
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memmove (secret, secret+1, secretlen);
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}
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else
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err = gpg_error (GPG_ERR_BAD_DATA);
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if (err)
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goto leave;
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if (DBG_CRYPTO)
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log_printhex (secret, secretlen, "ECDH X ..:");
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err = ecdh_derive_kek (key, keylen, hash_algo, wrap_algo_str,
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secret, secretlen, NULL, 0);
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if (err)
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goto leave;
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if (DBG_CRYPTO)
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log_printhex (key, keylen, "KEK .....:");
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/* Wrap the key. */
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if ((dek->keylen % 8) || dek->keylen < 16)
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{
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log_error ("%s: can't use a session key of %u bytes\n",
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__func__, dek->keylen);
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err = gpg_error (GPG_ERR_BAD_DATA);
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goto leave;
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}
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resultlen = dek->keylen + 8;
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result = xtrymalloc_secure (resultlen);
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if (!result)
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{
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err = gpg_error_from_syserror ();
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goto leave;
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}
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err = gcry_cipher_open (&cipher_hd, cipher_algo, GCRY_CIPHER_MODE_AESWRAP, 0);
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if (err)
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{
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log_error ("%s: failed to initialize AESWRAP: %s\n",
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__func__, gpg_strerror (err));
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goto leave;
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}
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err = gcry_cipher_setkey (cipher_hd, key, keylen);
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wipememory (key, sizeof key);
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if (err)
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{
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log_error ("%s: failed in gcry_cipher_setkey: %s\n",
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__func__, gpg_strerror (err));
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goto leave;
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}
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err = gcry_cipher_encrypt (cipher_hd, result, resultlen,
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dek->key, dek->keylen);
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if (err)
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{
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log_error ("%s: failed in gcry_cipher_encrypt: %s\n",
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__func__, gpg_strerror (err));
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goto leave;
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}
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if (DBG_CRYPTO)
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log_printhex (result, resultlen, "w(CEK) ..:");
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err = gcry_sexp_build (r_encval, NULL,
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"(enc-val(ecdh(e%b)(s%b)(encr-algo%s)(wrap-algo%s)))",
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(int)pubkeylen, pubkey,
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(int)resultlen, result,
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encr_algo_str,
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wrap_algo_str,
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NULL);
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if (err)
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log_error ("%s: failed building final S-exp: %s\n",
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__func__, gpg_strerror (err));
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leave:
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gcry_cipher_close (cipher_hd);
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wipememory (key, sizeof key);
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xfree (result);
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xfree (ioarray[0].data);
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xfree (ioarray[1].data);
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gcry_sexp_release (s_data);
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gcry_sexp_release (s_encr);
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xfree (curvebuf);
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return err;
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}
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/* Encrypt the DEK under the key contained in CERT and return it as a
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* canonical S-expressions at ENCVAL. PK_ALGO is the public key
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* algorithm which the caller has already retrieved from CERT. */
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static int
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encrypt_dek (const DEK dek, ksba_cert_t cert, int pk_algo,
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unsigned char **encval)
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{
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gcry_sexp_t s_ciph, s_data, s_pkey;
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int rc;
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ksba_sexp_t buf;
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size_t len;
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*encval = NULL;
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/* get the key from the cert */
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buf = ksba_cert_get_public_key (cert);
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if (!buf)
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{
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log_error ("no public key for recipient\n");
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return gpg_error (GPG_ERR_NO_PUBKEY);
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}
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len = gcry_sexp_canon_len (buf, 0, NULL, NULL);
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if (!len)
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{
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log_error ("libksba did not return a proper S-Exp\n");
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return gpg_error (GPG_ERR_BUG);
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}
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rc = gcry_sexp_sscan (&s_pkey, NULL, (char*)buf, len);
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xfree (buf); buf = NULL;
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if (rc)
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{
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log_error ("gcry_sexp_scan failed: %s\n", gpg_strerror (rc));
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return rc;
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}
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if (DBG_CRYPTO)
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{
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log_printsexp (" pubkey:", s_pkey);
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log_printhex (dek->key, dek->keylen, "CEK .....:");
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}
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/* Put the encoded cleartext into a simple list. */
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s_data = NULL; /* (avoid compiler warning) */
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if (pk_algo == GCRY_PK_ECC)
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{
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rc = ecdh_encrypt (dek, s_pkey, &s_ciph);
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}
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else
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{
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rc = encode_session_key (dek, &s_data);
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if (rc)
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{
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gcry_sexp_release (s_pkey);
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log_error ("encode_session_key failed: %s\n", gpg_strerror (rc));
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return rc;
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}
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if (DBG_CRYPTO)
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log_printsexp (" data:", s_data);
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/* pass it to libgcrypt */
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rc = gcry_pk_encrypt (&s_ciph, s_data, s_pkey);
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}
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gcry_sexp_release (s_data);
|
||
gcry_sexp_release (s_pkey);
|
||
|
||
if (DBG_CRYPTO)
|
||
log_printsexp ("enc-val:", s_ciph);
|
||
|
||
/* Reformat it. */
|
||
if (!rc)
|
||
{
|
||
rc = make_canon_sexp (s_ciph, encval, NULL);
|
||
gcry_sexp_release (s_ciph);
|
||
}
|
||
return rc;
|
||
}
|
||
|
||
|
||
|
||
/* do the actual encryption */
|
||
static int
|
||
encrypt_cb (void *cb_value, char *buffer, size_t count, size_t *nread)
|
||
{
|
||
struct encrypt_cb_parm_s *parm = cb_value;
|
||
int blklen = parm->dek->ivlen;
|
||
unsigned char *p;
|
||
size_t n;
|
||
|
||
*nread = 0;
|
||
if (!buffer)
|
||
return -1; /* not supported */
|
||
|
||
if (parm->ready)
|
||
return -1;
|
||
|
||
if (count < blklen)
|
||
BUG ();
|
||
|
||
if (!parm->eof_seen)
|
||
{ /* fillup the buffer */
|
||
p = parm->buffer;
|
||
for (n=parm->buflen; n < parm->bufsize; n++)
|
||
{
|
||
int c = es_getc (parm->fp);
|
||
if (c == EOF)
|
||
{
|
||
if (es_ferror (parm->fp))
|
||
{
|
||
parm->readerror = errno;
|
||
return -1;
|
||
}
|
||
parm->eof_seen = 1;
|
||
break;
|
||
}
|
||
p[n] = c;
|
||
}
|
||
parm->buflen = n;
|
||
}
|
||
|
||
n = parm->buflen < count? parm->buflen : count;
|
||
n = n/blklen * blklen;
|
||
if (n)
|
||
{ /* encrypt the stuff */
|
||
gcry_cipher_encrypt (parm->dek->chd, buffer, n, parm->buffer, n);
|
||
*nread = n;
|
||
/* Who cares about cycles, take the easy way and shift the buffer */
|
||
parm->buflen -= n;
|
||
memmove (parm->buffer, parm->buffer+n, parm->buflen);
|
||
}
|
||
else if (parm->eof_seen)
|
||
{ /* no complete block but eof: add padding */
|
||
/* fixme: we should try to do this also in the above code path */
|
||
int i, npad = blklen - (parm->buflen % blklen);
|
||
p = parm->buffer;
|
||
for (n=parm->buflen, i=0; n < parm->bufsize && i < npad; n++, i++)
|
||
p[n] = npad;
|
||
gcry_cipher_encrypt (parm->dek->chd, buffer, n, parm->buffer, n);
|
||
*nread = n;
|
||
parm->ready = 1;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
|
||
|
||
|
||
/* Perform an encrypt operation.
|
||
|
||
Encrypt the data received on DATA-FD and write it to OUT_FP. The
|
||
recipients are take from the certificate given in recplist; if this
|
||
is NULL it will be encrypted for a default recipient */
|
||
int
|
||
gpgsm_encrypt (ctrl_t ctrl, certlist_t recplist, estream_t data_fp,
|
||
estream_t out_fp)
|
||
{
|
||
int rc = 0;
|
||
gnupg_ksba_io_t b64writer = NULL;
|
||
gpg_error_t err;
|
||
ksba_writer_t writer;
|
||
ksba_reader_t reader = NULL;
|
||
ksba_cms_t cms = NULL;
|
||
ksba_stop_reason_t stopreason;
|
||
KEYDB_HANDLE kh = NULL;
|
||
struct encrypt_cb_parm_s encparm;
|
||
DEK dek = NULL;
|
||
int recpno;
|
||
certlist_t cl;
|
||
int count;
|
||
int compliant;
|
||
|
||
memset (&encparm, 0, sizeof encparm);
|
||
|
||
audit_set_type (ctrl->audit, AUDIT_TYPE_ENCRYPT);
|
||
|
||
/* Check that the certificate list is not empty and that at least
|
||
one certificate is not flagged as encrypt_to; i.e. is a real
|
||
recipient. */
|
||
for (cl = recplist; cl; cl = cl->next)
|
||
if (!cl->is_encrypt_to)
|
||
break;
|
||
if (!cl)
|
||
{
|
||
log_error(_("no valid recipients given\n"));
|
||
gpgsm_status (ctrl, STATUS_NO_RECP, "0");
|
||
audit_log_i (ctrl->audit, AUDIT_GOT_RECIPIENTS, 0);
|
||
rc = gpg_error (GPG_ERR_NO_PUBKEY);
|
||
goto leave;
|
||
}
|
||
|
||
for (count = 0, cl = recplist; cl; cl = cl->next)
|
||
count++;
|
||
audit_log_i (ctrl->audit, AUDIT_GOT_RECIPIENTS, count);
|
||
|
||
kh = keydb_new (ctrl);
|
||
if (!kh)
|
||
{
|
||
log_error (_("failed to allocate keyDB handle\n"));
|
||
rc = gpg_error (GPG_ERR_GENERAL);
|
||
goto leave;
|
||
}
|
||
|
||
err = ksba_reader_new (&reader);
|
||
if (err)
|
||
rc = err;
|
||
if (!rc)
|
||
rc = ksba_reader_set_cb (reader, encrypt_cb, &encparm);
|
||
if (rc)
|
||
goto leave;
|
||
|
||
encparm.fp = data_fp;
|
||
|
||
ctrl->pem_name = "ENCRYPTED MESSAGE";
|
||
rc = gnupg_ksba_create_writer
|
||
(&b64writer, ((ctrl->create_pem? GNUPG_KSBA_IO_PEM : 0)
|
||
| (ctrl->create_base64? GNUPG_KSBA_IO_BASE64 : 0)),
|
||
ctrl->pem_name, out_fp, &writer);
|
||
if (rc)
|
||
{
|
||
log_error ("can't create writer: %s\n", gpg_strerror (rc));
|
||
goto leave;
|
||
}
|
||
|
||
gnupg_ksba_set_progress_cb (b64writer, gpgsm_progress_cb, ctrl);
|
||
if (ctrl->input_size_hint)
|
||
gnupg_ksba_set_total (b64writer, ctrl->input_size_hint);
|
||
|
||
err = ksba_cms_new (&cms);
|
||
if (err)
|
||
{
|
||
rc = err;
|
||
goto leave;
|
||
}
|
||
|
||
err = ksba_cms_set_reader_writer (cms, reader, writer);
|
||
if (err)
|
||
{
|
||
log_error ("ksba_cms_set_reader_writer failed: %s\n",
|
||
gpg_strerror (err));
|
||
rc = err;
|
||
goto leave;
|
||
}
|
||
|
||
audit_log (ctrl->audit, AUDIT_GOT_DATA);
|
||
|
||
/* We are going to create enveloped data with uninterpreted data as
|
||
inner content */
|
||
err = ksba_cms_set_content_type (cms, 0, KSBA_CT_ENVELOPED_DATA);
|
||
if (!err)
|
||
err = ksba_cms_set_content_type (cms, 1, KSBA_CT_DATA);
|
||
if (err)
|
||
{
|
||
log_error ("ksba_cms_set_content_type failed: %s\n",
|
||
gpg_strerror (err));
|
||
rc = err;
|
||
goto leave;
|
||
}
|
||
|
||
/* Check compliance. */
|
||
if (!gnupg_cipher_is_allowed
|
||
(opt.compliance, 1, gcry_cipher_map_name (opt.def_cipher_algoid),
|
||
gcry_cipher_mode_from_oid (opt.def_cipher_algoid)))
|
||
{
|
||
log_error (_("cipher algorithm '%s' may not be used in %s mode\n"),
|
||
opt.def_cipher_algoid,
|
||
gnupg_compliance_option_string (opt.compliance));
|
||
rc = gpg_error (GPG_ERR_CIPHER_ALGO);
|
||
goto leave;
|
||
}
|
||
|
||
if (!gnupg_rng_is_compliant (opt.compliance))
|
||
{
|
||
rc = gpg_error (GPG_ERR_FORBIDDEN);
|
||
log_error (_("%s is not compliant with %s mode\n"),
|
||
"RNG",
|
||
gnupg_compliance_option_string (opt.compliance));
|
||
gpgsm_status_with_error (ctrl, STATUS_ERROR,
|
||
"random-compliance", rc);
|
||
goto leave;
|
||
}
|
||
|
||
/* Create a session key */
|
||
dek = xtrycalloc_secure (1, sizeof *dek);
|
||
if (!dek)
|
||
rc = out_of_core ();
|
||
else
|
||
{
|
||
dek->algoid = opt.def_cipher_algoid;
|
||
rc = init_dek (dek);
|
||
}
|
||
if (rc)
|
||
{
|
||
log_error ("failed to create the session key: %s\n",
|
||
gpg_strerror (rc));
|
||
goto leave;
|
||
}
|
||
|
||
err = ksba_cms_set_content_enc_algo (cms, dek->algoid, dek->iv, dek->ivlen);
|
||
if (err)
|
||
{
|
||
log_error ("ksba_cms_set_content_enc_algo failed: %s\n",
|
||
gpg_strerror (err));
|
||
rc = err;
|
||
goto leave;
|
||
}
|
||
|
||
encparm.dek = dek;
|
||
/* Use a ~8k (AES) or ~4k (3DES) buffer */
|
||
encparm.bufsize = 500 * dek->ivlen;
|
||
encparm.buffer = xtrymalloc (encparm.bufsize);
|
||
if (!encparm.buffer)
|
||
{
|
||
rc = out_of_core ();
|
||
goto leave;
|
||
}
|
||
|
||
audit_log_s (ctrl->audit, AUDIT_SESSION_KEY, dek->algoid);
|
||
|
||
compliant = gnupg_cipher_is_compliant (CO_DE_VS, dek->algo,
|
||
GCRY_CIPHER_MODE_CBC);
|
||
|
||
/* Gather certificates of recipients, encrypt the session key for
|
||
each and store them in the CMS object */
|
||
for (recpno = 0, cl = recplist; cl; recpno++, cl = cl->next)
|
||
{
|
||
unsigned char *encval;
|
||
unsigned int nbits;
|
||
int pk_algo;
|
||
char *curve = NULL;
|
||
|
||
/* Check compliance. */
|
||
pk_algo = gpgsm_get_key_algo_info (cl->cert, &nbits, &curve);
|
||
if (!gnupg_pk_is_compliant (opt.compliance, pk_algo, 0,
|
||
NULL, nbits, curve))
|
||
{
|
||
char kidstr[10+1];
|
||
|
||
snprintf (kidstr, sizeof kidstr, "0x%08lX",
|
||
gpgsm_get_short_fingerprint (cl->cert, NULL));
|
||
log_info (_("WARNING: key %s is not suitable for encryption"
|
||
" in %s mode\n"),
|
||
kidstr,
|
||
gnupg_compliance_option_string (opt.compliance));
|
||
}
|
||
|
||
/* Fixme: When adding ECC we need to provide the curvename and
|
||
* the key to gnupg_pk_is_compliant. */
|
||
if (compliant
|
||
&& !gnupg_pk_is_compliant (CO_DE_VS, pk_algo, 0, NULL, nbits, curve))
|
||
compliant = 0;
|
||
|
||
xfree (curve);
|
||
curve = NULL;
|
||
|
||
rc = encrypt_dek (dek, cl->cert, pk_algo, &encval);
|
||
if (rc)
|
||
{
|
||
audit_log_cert (ctrl->audit, AUDIT_ENCRYPTED_TO, cl->cert, rc);
|
||
log_error ("encryption failed for recipient no. %d: %s\n",
|
||
recpno, gpg_strerror (rc));
|
||
goto leave;
|
||
}
|
||
|
||
err = ksba_cms_add_recipient (cms, cl->cert);
|
||
if (err)
|
||
{
|
||
audit_log_cert (ctrl->audit, AUDIT_ENCRYPTED_TO, cl->cert, err);
|
||
log_error ("ksba_cms_add_recipient failed: %s\n",
|
||
gpg_strerror (err));
|
||
rc = err;
|
||
xfree (encval);
|
||
goto leave;
|
||
}
|
||
|
||
err = ksba_cms_set_enc_val (cms, recpno, encval);
|
||
xfree (encval);
|
||
audit_log_cert (ctrl->audit, AUDIT_ENCRYPTED_TO, cl->cert, err);
|
||
if (err)
|
||
{
|
||
log_error ("ksba_cms_set_enc_val failed: %s\n",
|
||
gpg_strerror (err));
|
||
rc = err;
|
||
goto leave;
|
||
}
|
||
}
|
||
|
||
if (compliant && gnupg_gcrypt_is_compliant (CO_DE_VS))
|
||
gpgsm_status (ctrl, STATUS_ENCRYPTION_COMPLIANCE_MODE,
|
||
gnupg_status_compliance_flag (CO_DE_VS));
|
||
else if (opt.require_compliance
|
||
&& opt.compliance == CO_DE_VS)
|
||
{
|
||
log_error (_("operation forced to fail due to"
|
||
" unfulfilled compliance rules\n"));
|
||
gpgsm_errors_seen = 1;
|
||
rc = gpg_error (GPG_ERR_FORBIDDEN);
|
||
goto leave;
|
||
}
|
||
|
||
/* Main control loop for encryption. */
|
||
recpno = 0;
|
||
do
|
||
{
|
||
err = ksba_cms_build (cms, &stopreason);
|
||
if (err)
|
||
{
|
||
log_error ("creating CMS object failed: %s\n", gpg_strerror (err));
|
||
rc = err;
|
||
goto leave;
|
||
}
|
||
}
|
||
while (stopreason != KSBA_SR_READY);
|
||
|
||
if (encparm.readerror)
|
||
{
|
||
log_error ("error reading input: %s\n", strerror (encparm.readerror));
|
||
rc = gpg_error (gpg_err_code_from_errno (encparm.readerror));
|
||
goto leave;
|
||
}
|
||
|
||
|
||
rc = gnupg_ksba_finish_writer (b64writer);
|
||
if (rc)
|
||
{
|
||
log_error ("write failed: %s\n", gpg_strerror (rc));
|
||
goto leave;
|
||
}
|
||
audit_log (ctrl->audit, AUDIT_ENCRYPTION_DONE);
|
||
if (!opt.quiet)
|
||
log_info ("encrypted data created\n");
|
||
|
||
leave:
|
||
ksba_cms_release (cms);
|
||
gnupg_ksba_destroy_writer (b64writer);
|
||
ksba_reader_release (reader);
|
||
keydb_release (kh);
|
||
xfree (dek);
|
||
xfree (encparm.buffer);
|
||
return rc;
|
||
}
|