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authorWerner Koch <[email protected]>2006-08-01 12:23:34 +0000
committerWerner Koch <[email protected]>2006-08-01 12:23:34 +0000
commit8c219602515ae1dba5bc0da31077852dab61809e (patch)
tree49d596d702cfec2b8cc42ccaf8c90c82d5200ac5 /agent/pkdecrypt.c
parentForgot this one. (diff)
parent2006-07-29 Marcus Brinkmann <[email protected]> (diff)
downloadgnupg-8c219602515ae1dba5bc0da31077852dab61809e.tar.gz
gnupg-8c219602515ae1dba5bc0da31077852dab61809e.zip
Moved 1.9 branch to trunk
Diffstat (limited to '')
-rw-r--r--agent/pkdecrypt.c142
1 files changed, 142 insertions, 0 deletions
diff --git a/agent/pkdecrypt.c b/agent/pkdecrypt.c
new file mode 100644
index 000000000..f61f0f844
--- /dev/null
+++ b/agent/pkdecrypt.c
@@ -0,0 +1,142 @@
+/* pkdecrypt.c - public key decryption (well, acually using a secret key)
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
+ */
+
+#include <config.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#include "agent.h"
+
+
+/* DECRYPT the stuff in ciphertext which is expected to be a S-Exp.
+ Try to get the key from CTRL and write the decoded stuff back to
+ OUTFP. */
+int
+agent_pkdecrypt (CTRL ctrl, const char *desc_text,
+ const unsigned char *ciphertext, size_t ciphertextlen,
+ membuf_t *outbuf)
+{
+ gcry_sexp_t s_skey = NULL, s_cipher = NULL, s_plain = NULL;
+ unsigned char *shadow_info = NULL;
+ int rc;
+ char *buf = NULL;
+ size_t len;
+
+ if (!ctrl->have_keygrip)
+ {
+ log_error ("speculative decryption not yet supported\n");
+ rc = gpg_error (GPG_ERR_NO_SECKEY);
+ goto leave;
+ }
+
+ rc = gcry_sexp_sscan (&s_cipher, NULL, (char*)ciphertext, ciphertextlen);
+ if (rc)
+ {
+ log_error ("failed to convert ciphertext: %s\n", gpg_strerror (rc));
+ rc = gpg_error (GPG_ERR_INV_DATA);
+ goto leave;
+ }
+
+ if (DBG_CRYPTO)
+ {
+ log_printhex ("keygrip:", ctrl->keygrip, 20);
+ log_printhex ("cipher: ", ciphertext, ciphertextlen);
+ }
+ rc = agent_key_from_file (ctrl, desc_text,
+ ctrl->keygrip, &shadow_info,
+ CACHE_MODE_NORMAL, &s_skey);
+ if (rc)
+ {
+ log_error ("failed to read the secret key\n");
+ goto leave;
+ }
+
+ if (!s_skey)
+ { /* divert operation to the smartcard */
+
+ if (!gcry_sexp_canon_len (ciphertext, ciphertextlen, NULL, NULL))
+ {
+ rc = gpg_error (GPG_ERR_INV_SEXP);
+ goto leave;
+ }
+
+ rc = divert_pkdecrypt (ctrl, ciphertext, shadow_info, &buf, &len );
+ if (rc)
+ {
+ log_error ("smartcard decryption failed: %s\n", gpg_strerror (rc));
+ goto leave;
+ }
+ /* FIXME: Change the protocol to return a complete S-expression
+ and not just a part. */
+ {
+ char tmpbuf[50];
+
+ sprintf (tmpbuf, "%u:", (unsigned int)len);
+ put_membuf (outbuf, tmpbuf, strlen (tmpbuf));
+ put_membuf (outbuf, buf, len);
+ put_membuf (outbuf, "", 1);
+ }
+ }
+ else
+ { /* No smartcard, but a private key */
+/* if (DBG_CRYPTO ) */
+/* { */
+/* log_debug ("skey: "); */
+/* gcry_sexp_dump (s_skey); */
+/* } */
+
+ rc = gcry_pk_decrypt (&s_plain, s_cipher, s_skey);
+ if (rc)
+ {
+ log_error ("decryption failed: %s\n", gpg_strerror (rc));
+ goto leave;
+ }
+
+ if (DBG_CRYPTO)
+ {
+ log_debug ("plain: ");
+ gcry_sexp_dump (s_plain);
+ }
+ len = gcry_sexp_sprint (s_plain, GCRYSEXP_FMT_CANON, NULL, 0);
+ assert (len);
+ buf = xmalloc (len);
+ len = gcry_sexp_sprint (s_plain, GCRYSEXP_FMT_CANON, buf, len);
+ assert (len);
+ put_membuf (outbuf, buf, len);
+ }
+
+
+ leave:
+ gcry_sexp_release (s_skey);
+ gcry_sexp_release (s_plain);
+ gcry_sexp_release (s_cipher);
+ xfree (buf);
+ xfree (shadow_info);
+ return rc;
+}
+
+