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-rw-r--r--sm/encrypt.c550
1 files changed, 0 insertions, 550 deletions
diff --git a/sm/encrypt.c b/sm/encrypt.c
deleted file mode 100644
index 725a81b70..000000000
--- a/sm/encrypt.c
+++ /dev/null
@@ -1,550 +0,0 @@
-/* encrypt.c - Encrypt a message
- * Copyright (C) 2001, 2003 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 2 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
- */
-
-#include <config.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <unistd.h>
-#include <time.h>
-#include <assert.h>
-
-#include "gpgsm.h"
-#include <gcrypt.h>
-#include <ksba.h>
-
-#include "keydb.h"
-#include "i18n.h"
-
-
-struct dek_s {
- const char *algoid;
- int algo;
- gcry_cipher_hd_t chd;
- char key[32];
- int keylen;
- char iv[32];
- int ivlen;
-};
-typedef struct dek_s *DEK;
-
-struct encrypt_cb_parm_s {
- FILE *fp;
- DEK dek;
- int eof_seen;
- int ready;
- int readerror;
- int bufsize;
- unsigned char *buffer;
- int buflen;
-};
-
-
-
-
-
-/* initialize the data encryptionkey (session key) */
-static int
-init_dek (DEK dek)
-{
- int rc=0, mode, i;
-
- dek->algo = gcry_cipher_map_name (dek->algoid);
- mode = gcry_cipher_mode_from_oid (dek->algoid);
- if (!dek->algo || !mode)
- {
- log_error ("unsupported algorithm `%s'\n", dek->algoid);
- return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
- }
-
- dek->keylen = gcry_cipher_get_algo_keylen (dek->algo);
- if (!dek->keylen || dek->keylen > sizeof (dek->key))
- return gpg_error (GPG_ERR_BUG);
-
- dek->ivlen = gcry_cipher_get_algo_blklen (dek->algo);
- if (!dek->ivlen || dek->ivlen > sizeof (dek->iv))
- return gpg_error (GPG_ERR_BUG);
-
- if (dek->keylen < 100/8)
- { /* make sure we don't use weak keys */
- log_error ("key length of `%s' too small\n", dek->algoid);
- return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
- }
-
- rc = gcry_cipher_open (&dek->chd, dek->algo, mode, GCRY_CIPHER_SECURE);
- if (rc)
- {
- log_error ("failed to create cipher context: %s\n", gpg_strerror (rc));
- return rc;
- }
-
- for (i=0; i < 8; i++)
- {
- gcry_randomize (dek->key, dek->keylen, GCRY_STRONG_RANDOM );
- rc = gcry_cipher_setkey (dek->chd, dek->key, dek->keylen);
- if (gpg_err_code (rc) != GPG_ERR_WEAK_KEY)
- break;
- log_info(_("weak key created - retrying\n") );
- }
- if (rc)
- {
- log_error ("failed to set the key: %s\n", gpg_strerror (rc));
- gcry_cipher_close (dek->chd);
- dek->chd = NULL;
- return rc;
- }
-
- gcry_randomize (dek->iv, dek->ivlen, GCRY_STRONG_RANDOM);
- rc = gcry_cipher_setiv (dek->chd, dek->iv, dek->ivlen);
- if (rc)
- {
- log_error ("failed to set the IV: %s\n", gpg_strerror (rc));
- gcry_cipher_close (dek->chd);
- dek->chd = NULL;
- return rc;
- }
-
- return 0;
-}
-
-
-/* Encode the session key. NBITS is the number of bits which should be
- used for packing the session key. returns: An mpi with the session
- key (caller must free) */
-static gcry_mpi_t
-encode_session_key (DEK dek, unsigned int nbits)
-{
- int nframe = (nbits+7) / 8;
- byte *p;
- byte *frame;
- int i,n;
- gcry_mpi_t a;
-
- if (dek->keylen + 7 > nframe || !nframe)
- log_bug ("can't encode a %d bit key in a %d bits frame\n",
- dek->keylen*8, nbits );
-
- /* We encode the session key in this way:
- *
- * 0 2 RND(n bytes) 0 KEY(k bytes)
- *
- * (But how can we store the leading 0 - the external representaion
- * of MPIs doesn't allow leading zeroes =:-)
- *
- * RND are non-zero random bytes.
- * KEY is the encryption key (session key)
- */
-
- frame = gcry_xmalloc_secure (nframe);
- n = 0;
- frame[n++] = 0;
- frame[n++] = 2;
- i = nframe - 3 - dek->keylen;
- assert (i > 0);
- p = gcry_random_bytes_secure (i, GCRY_STRONG_RANDOM);
- /* replace zero bytes by new values */
- for (;;)
- {
- int j, k;
- byte *pp;
-
- /* count the zero bytes */
- for(j=k=0; j < i; j++ )
- {
- if( !p[j] )
- k++;
- }
- if( !k )
- break; /* okay: no zero bytes */
-
- k += k/128; /* better get some more */
- pp = gcry_random_bytes_secure (k, GCRY_STRONG_RANDOM);
- for (j=0; j < i && k; j++)
- {
- if( !p[j] )
- p[j] = pp[--k];
- }
- xfree (pp);
- }
- memcpy (frame+n, p, i);
- xfree (p);
-
- n += i;
- frame[n++] = 0;
- memcpy (frame+n, dek->key, dek->keylen);
- n += dek->keylen;
- assert (n == nframe);
- if (gcry_mpi_scan (&a, GCRYMPI_FMT_USG, frame, n, &nframe) )
- BUG ();
- gcry_free(frame);
-
- return a;
-}
-
-
-
-/* encrypt the DEK under the key contained in CERT and return it as a
- canonical S-Exp in encval */
-static int
-encrypt_dek (const DEK dek, KsbaCert cert, char **encval)
-{
- gcry_sexp_t s_ciph, s_data, s_pkey;
- int rc;
- KsbaSexp buf;
- size_t len;
-
- *encval = NULL;
-
- /* get the key from the cert */
- buf = ksba_cert_get_public_key (cert);
- if (!buf)
- {
- log_error ("no public key for recipient\n");
- return gpg_error (GPG_ERR_NO_PUBKEY);
- }
- len = gcry_sexp_canon_len (buf, 0, NULL, NULL);
- if (!len)
- {
- log_error ("libksba did not return a proper S-Exp\n");
- return gpg_error (GPG_ERR_BUG);
- }
- rc = gcry_sexp_sscan (&s_pkey, NULL, buf, len);
- xfree (buf); buf = NULL;
- if (rc)
- {
- log_error ("gcry_sexp_scan failed: %s\n", gpg_strerror (rc));
- return rc;
- }
-
- /* put the encoded cleartext into a simple list */
- {
- /* fixme: actually the pkcs-1 encoding should go into libgcrypt */
- gcry_mpi_t data = encode_session_key (dek, gcry_pk_get_nbits (s_pkey));
- if (!data)
- {
- gcry_mpi_release (data);
- return gpg_error (GPG_ERR_GENERAL);
- }
- if (gcry_sexp_build (&s_data, NULL, "%m", data))
- BUG ();
- gcry_mpi_release (data);
- }
-
- /* pass it to libgcrypt */
- rc = gcry_pk_encrypt (&s_ciph, s_data, s_pkey);
- gcry_sexp_release (s_data);
- gcry_sexp_release (s_pkey);
-
- /* reformat it */
- len = gcry_sexp_sprint (s_ciph, GCRYSEXP_FMT_CANON, NULL, 0);
- assert (len);
- buf = xtrymalloc (len);
- if (!buf)
- {
- gpg_error_t tmperr = OUT_OF_CORE (errno);
- gcry_sexp_release (s_ciph);
- return tmperr;
- }
- len = gcry_sexp_sprint (s_ciph, GCRYSEXP_FMT_CANON, buf, len);
- assert (len);
-
- *encval = buf;
- return 0;
-}
-
-
-
-/* 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 = getc (parm->fp);
- if (c == EOF)
- {
- if (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 ctrl, CERTLIST recplist, int data_fd, FILE *out_fp)
-{
- int rc = 0;
- Base64Context b64writer = NULL;
- KsbaError err;
- KsbaWriter writer;
- KsbaReader reader = NULL;
- KsbaCMS cms = NULL;
- KsbaStopReason stopreason;
- KEYDB_HANDLE kh = NULL;
- struct encrypt_cb_parm_s encparm;
- DEK dek = NULL;
- int recpno;
- FILE *data_fp = NULL;
- CERTLIST cl;
-
- memset (&encparm, 0, sizeof encparm);
-
- if (!recplist)
- {
- log_error(_("no valid recipients given\n"));
- gpgsm_status (ctrl, STATUS_NO_RECP, "0");
- rc = gpg_error (GPG_ERR_NO_PUBKEY);
- goto leave;
- }
-
- kh = keydb_new (0);
- if (!kh)
- {
- log_error (_("failed to allocated keyDB handle\n"));
- rc = gpg_error (GPG_ERR_GENERAL);
- goto leave;
- }
-
- data_fp = fdopen ( dup (data_fd), "rb");
- if (!data_fp)
- {
- rc = gpg_error (gpg_err_code_from_errno (errno));
- log_error ("fdopen() failed: %s\n", strerror (errno));
- goto leave;
- }
-
- reader = ksba_reader_new ();
- if (!reader)
- rc = KSBA_Out_Of_Core;
- if (!rc)
- rc = ksba_reader_set_cb (reader, encrypt_cb, &encparm);
- if (rc)
- {
- rc = map_ksba_err (rc);
- goto leave;
- }
- encparm.fp = data_fp;
-
- ctrl->pem_name = "ENCRYPTED MESSAGE";
- rc = gpgsm_create_writer (&b64writer, ctrl, out_fp, &writer);
- if (rc)
- {
- log_error ("can't create writer: %s\n", gpg_strerror (rc));
- goto leave;
- }
-
- cms = ksba_cms_new ();
- if (!cms)
- {
- rc = gpg_error (GPG_ERR_ENOMEM);
- goto leave;
- }
-
- err = ksba_cms_set_reader_writer (cms, reader, writer);
- if (err)
- {
- log_debug ("ksba_cms_set_reader_writer failed: %s\n",
- ksba_strerror (err));
- rc = map_ksba_err (err);
- goto leave;
- }
-
- /* 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_debug ("ksba_cms_set_content_type failed: %s\n",
- ksba_strerror (err));
- rc = map_ksba_err (err);
- goto leave;
- }
-
- /* create a session key */
- dek = xtrycalloc (1, sizeof *dek); /* hmmm: should we put it into secmem?*/
- if (!dek)
- rc = OUT_OF_CORE (errno);
- 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",
- ksba_strerror (err));
- rc = map_ksba_err (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 (errno);
- goto leave;
- }
-
- /* 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)
- {
- char *encval;
-
- rc = encrypt_dek (dek, cl->cert, &encval);
- if (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)
- {
- log_error ("ksba_cms_add_recipient failed: %s\n",
- ksba_strerror (err));
- rc = map_ksba_err (err);
- xfree (encval);
- goto leave;
- }
-
- err = ksba_cms_set_enc_val (cms, recpno, encval);
- xfree (encval);
- if (err)
- {
- log_error ("ksba_cms_set_enc_val failed: %s\n",
- ksba_strerror (err));
- rc = map_ksba_err (err);
- goto leave;
- }
- }
-
- /* main control loop for encryption */
- recpno = 0;
- do
- {
- err = ksba_cms_build (cms, &stopreason);
- if (err)
- {
- log_debug ("ksba_cms_build failed: %s\n", ksba_strerror (err));
- rc = map_ksba_err (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 = gpgsm_finish_writer (b64writer);
- if (rc)
- {
- log_error ("write failed: %s\n", gpg_strerror (rc));
- goto leave;
- }
- log_info ("encrypted data created\n");
-
- leave:
- ksba_cms_release (cms);
- gpgsm_destroy_writer (b64writer);
- ksba_reader_release (reader);
- keydb_release (kh);
- xfree (dek);
- if (data_fp)
- fclose (data_fp);
- xfree (encparm.buffer);
- return rc;
-}
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