Adding upstream version 2.2.40.upstream/2.2.40

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 453 insertions, 0 deletions

diff --git a/g10/pkglue.c b/g10/pkglue.c
new file mode 100644
index 0000000..e053657
--- /dev/null
+++ b/g10/pkglue.c
@@ -0,0 +1,453 @@
+/* pkglue.c - public key operations glue code
+ * Copyright (C) 2000, 2003, 2010 Free Software Foundation, Inc.
+ * Copyright (C) 2014 Werner Koch
+ *
+ * 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 "gpg.h"
+#include "../common/util.h"
+#include "pkglue.h"
+#include "main.h"
+#include "options.h"
+
+/* FIXME: Better change the function name because mpi_ is used by
+   gcrypt macros.  */
+gcry_mpi_t
+get_mpi_from_sexp (gcry_sexp_t sexp, const char *item, int mpifmt)
+{
+  gcry_sexp_t list;
+  gcry_mpi_t data;
+
+  list = gcry_sexp_find_token (sexp, item, 0);
+  log_assert (list);
+  data = gcry_sexp_nth_mpi (list, 1, mpifmt);
+  log_assert (data);
+  gcry_sexp_release (list);
+  return data;
+}
+
+
+static byte *
+get_data_from_sexp (gcry_sexp_t sexp, const char *item, size_t *r_size)
+{
+  gcry_sexp_t list;
+  size_t valuelen;
+  const char *value;
+  byte *v;
+
+  if (DBG_CRYPTO)
+    log_printsexp ("get_data_from_sexp:", sexp);
+
+  list = gcry_sexp_find_token (sexp, item, 0);
+  log_assert (list);
+  value = gcry_sexp_nth_data (list, 1, &valuelen);
+  log_assert (value);
+  v = xtrymalloc (valuelen);
+  memcpy (v, value, valuelen);
+  gcry_sexp_release (list);
+  *r_size = valuelen;
+  return v;
+}
+
+
+/****************
+ * Emulate our old PK interface here - sometime in the future we might
+ * change the internal design to directly fit to libgcrypt.
+ */
+int
+pk_verify (pubkey_algo_t pkalgo, gcry_mpi_t hash,
+           gcry_mpi_t *data, gcry_mpi_t *pkey)
+{
+  gcry_sexp_t s_sig, s_hash, s_pkey;
+  int rc;
+  unsigned int neededfixedlen = 0;
+
+  /* Make a sexp from pkey.  */
+  if (pkalgo == PUBKEY_ALGO_DSA)
+    {
+      rc = gcry_sexp_build (&s_pkey, NULL,
+			    "(public-key(dsa(p%m)(q%m)(g%m)(y%m)))",
+			    pkey[0], pkey[1], pkey[2], pkey[3]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_ELGAMAL_E || pkalgo == PUBKEY_ALGO_ELGAMAL)
+    {
+      rc = gcry_sexp_build (&s_pkey, NULL,
+			    "(public-key(elg(p%m)(g%m)(y%m)))",
+			    pkey[0], pkey[1], pkey[2]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_RSA || pkalgo == PUBKEY_ALGO_RSA_S)
+    {
+      rc = gcry_sexp_build (&s_pkey, NULL,
+			    "(public-key(rsa(n%m)(e%m)))", pkey[0], pkey[1]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_ECDSA)
+    {
+      char *curve = openpgp_oid_to_str (pkey[0]);
+      if (!curve)
+        rc = gpg_error_from_syserror ();
+      else
+        {
+          rc = gcry_sexp_build (&s_pkey, NULL,
+                                "(public-key(ecdsa(curve %s)(q%m)))",
+                                curve, pkey[1]);
+          xfree (curve);
+        }
+    }
+  else if (pkalgo == PUBKEY_ALGO_EDDSA)
+    {
+      char *curve = openpgp_oid_to_str (pkey[0]);
+      if (!curve)
+        rc = gpg_error_from_syserror ();
+      else
+        {
+          rc = gcry_sexp_build (&s_pkey, NULL,
+                                "(public-key(ecc(curve %s)"
+                                "(flags eddsa)(q%m)))",
+                                curve, pkey[1]);
+          xfree (curve);
+        }
+
+      if (openpgp_oid_is_ed25519 (pkey[0]))
+        neededfixedlen = 256 / 8;
+    }
+  else
+    return GPG_ERR_PUBKEY_ALGO;
+
+  if (rc)
+    BUG ();  /* gcry_sexp_build should never fail.  */
+
+  /* Put hash into a S-Exp s_hash. */
+  if (pkalgo == PUBKEY_ALGO_EDDSA)
+    {
+      if (gcry_sexp_build (&s_hash, NULL,
+                           "(data(flags eddsa)(hash-algo sha512)(value %m))",
+                           hash))
+        BUG (); /* gcry_sexp_build should never fail.  */
+    }
+  else
+    {
+      if (gcry_sexp_build (&s_hash, NULL, "%m", hash))
+        BUG (); /* gcry_sexp_build should never fail.  */
+    }
+
+  /* Put data into a S-Exp s_sig. */
+  s_sig = NULL;
+  if (pkalgo == PUBKEY_ALGO_DSA)
+    {
+      if (!data[0] || !data[1])
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else
+        rc = gcry_sexp_build (&s_sig, NULL,
+                              "(sig-val(dsa(r%m)(s%m)))", data[0], data[1]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_ECDSA)
+    {
+      if (!data[0] || !data[1])
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else
+        rc = gcry_sexp_build (&s_sig, NULL,
+                              "(sig-val(ecdsa(r%m)(s%m)))", data[0], data[1]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_EDDSA)
+    {
+      gcry_mpi_t r = data[0];
+      gcry_mpi_t s = data[1];
+      size_t rlen, slen, n;  /* (bytes) */
+      char buf[64];
+
+      log_assert (neededfixedlen <= sizeof buf);
+
+      if (!r || !s)
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else if ((rlen = (gcry_mpi_get_nbits (r)+7)/8) > neededfixedlen || !rlen)
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else if ((slen = (gcry_mpi_get_nbits (s)+7)/8) > neededfixedlen || !slen)
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else
+        {
+          /* We need to fixup the length in case of leading zeroes.
+           * OpenPGP does not allow leading zeroes and the parser for
+           * the signature packet has no information on the use curve,
+           * thus we need to do it here.  We won't do it for opaque
+           * MPIs under the assumption that they are known to be fine;
+           * we won't see them here anyway but the check is anyway
+           * required.  Fixme: A nifty feature for gcry_sexp_build
+           * would be a format to left pad the value (e.g. "%*M"). */
+          rc = 0;
+
+          if (rlen < neededfixedlen
+              && !gcry_mpi_get_flag (r, GCRYMPI_FLAG_OPAQUE)
+              && !(rc=gcry_mpi_print (GCRYMPI_FMT_USG, buf, sizeof buf, &n, r)))
+            {
+              log_assert (n < neededfixedlen);
+              memmove (buf + (neededfixedlen - n), buf, n);
+              memset (buf, 0, neededfixedlen - n);
+              r = gcry_mpi_set_opaque_copy (NULL, buf, neededfixedlen * 8);
+            }
+          if (slen < neededfixedlen
+              && !gcry_mpi_get_flag (s, GCRYMPI_FLAG_OPAQUE)
+              && !(rc=gcry_mpi_print (GCRYMPI_FMT_USG, buf, sizeof buf, &n, s)))
+            {
+              log_assert (n < neededfixedlen);
+              memmove (buf + (neededfixedlen - n), buf, n);
+              memset (buf, 0, neededfixedlen - n);
+              s = gcry_mpi_set_opaque_copy (NULL, buf, neededfixedlen * 8);
+            }
+
+          if (!rc)
+            rc = gcry_sexp_build (&s_sig, NULL,
+                                  "(sig-val(eddsa(r%M)(s%M)))", r, s);
+
+          if (r != data[0])
+            gcry_mpi_release (r);
+          if (s != data[1])
+            gcry_mpi_release (s);
+        }
+    }
+  else if (pkalgo == PUBKEY_ALGO_ELGAMAL || pkalgo == PUBKEY_ALGO_ELGAMAL_E)
+    {
+      if (!data[0] || !data[1])
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else
+        rc = gcry_sexp_build (&s_sig, NULL,
+                              "(sig-val(elg(r%m)(s%m)))", data[0], data[1]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_RSA || pkalgo == PUBKEY_ALGO_RSA_S)
+    {
+      if (!data[0])
+        rc = gpg_error (GPG_ERR_BAD_MPI);
+      else
+        rc = gcry_sexp_build (&s_sig, NULL, "(sig-val(rsa(s%m)))", data[0]);
+    }
+  else
+    BUG ();
+
+  if (!rc)
+    rc = gcry_pk_verify (s_sig, s_hash, s_pkey);
+
+  gcry_sexp_release (s_sig);
+  gcry_sexp_release (s_hash);
+  gcry_sexp_release (s_pkey);
+  return rc;
+}
+
+
+
+
+/****************
+ * Emulate our old PK interface here - sometime in the future we might
+ * change the internal design to directly fit to libgcrypt.
+ * PK is only required to compute the fingerprint for ECDH.
+ */
+int
+pk_encrypt (pubkey_algo_t algo, gcry_mpi_t *resarr, gcry_mpi_t data,
+            PKT_public_key *pk, gcry_mpi_t *pkey)
+{
+  gcry_sexp_t s_ciph = NULL;
+  gcry_sexp_t s_data = NULL;
+  gcry_sexp_t s_pkey = NULL;
+  int rc;
+
+  /* Make a sexp from pkey.  */
+  if (algo == PUBKEY_ALGO_ELGAMAL || algo == PUBKEY_ALGO_ELGAMAL_E)
+    {
+      rc = gcry_sexp_build (&s_pkey, NULL,
+			    "(public-key(elg(p%m)(g%m)(y%m)))",
+			    pkey[0], pkey[1], pkey[2]);
+      /* Put DATA into a simplified S-expression.  */
+      if (!rc)
+        rc = gcry_sexp_build (&s_data, NULL, "%m", data);
+    }
+  else if (algo == PUBKEY_ALGO_RSA || algo == PUBKEY_ALGO_RSA_E)
+    {
+      rc = gcry_sexp_build (&s_pkey, NULL,
+			    "(public-key(rsa(n%m)(e%m)))",
+			    pkey[0], pkey[1]);
+      /* Put DATA into a simplified S-expression.  */
+      if (!rc)
+        rc = gcry_sexp_build (&s_data, NULL, "%m", data);
+    }
+  else if (algo == PUBKEY_ALGO_ECDH)
+    {
+      gcry_mpi_t k;
+
+      rc = pk_ecdh_generate_ephemeral_key (pkey, &k);
+      if (!rc)
+        {
+          char *curve;
+
+          curve = openpgp_oid_to_str (pkey[0]);
+          if (!curve)
+            rc = gpg_error_from_syserror ();
+          else
+            {
+              int with_djb_tweak_flag = openpgp_oid_is_cv25519 (pkey[0]);
+
+              /* Now use the ephemeral secret to compute the shared point.  */
+              rc = gcry_sexp_build (&s_pkey, NULL,
+                                    with_djb_tweak_flag ?
+                                    "(public-key(ecdh(curve%s)(flags djb-tweak)(q%m)))"
+                                    : "(public-key(ecdh(curve%s)(q%m)))",
+                                    curve, pkey[1]);
+              xfree (curve);
+              /* Put K into a simplified S-expression.  */
+              if (!rc)
+                rc = gcry_sexp_build (&s_data, NULL, "%m", k);
+            }
+          gcry_mpi_release (k);
+        }
+    }
+  else
+    rc = gpg_error (GPG_ERR_PUBKEY_ALGO);
+
+  /* Pass it to libgcrypt. */
+  if (!rc)
+    rc = gcry_pk_encrypt (&s_ciph, s_data, s_pkey);
+
+  gcry_sexp_release (s_data);
+  gcry_sexp_release (s_pkey);
+
+  if (rc)
+    ;
+  else if (algo == PUBKEY_ALGO_ECDH)
+    {
+      gcry_mpi_t public, result;
+      byte fp[MAX_FINGERPRINT_LEN];
+      size_t fpn;
+      byte *shared;
+      size_t nshared;
+
+      /* Get the shared point and the ephemeral public key.  */
+      shared = get_data_from_sexp (s_ciph, "s", &nshared);
+      if (!shared)
+        {
+          rc = gpg_error_from_syserror ();
+          goto leave;
+        }
+      public = get_mpi_from_sexp (s_ciph, "e", GCRYMPI_FMT_USG);
+      gcry_sexp_release (s_ciph);
+      s_ciph = NULL;
+      if (DBG_CRYPTO)
+        {
+          log_debug ("ECDH ephemeral key:");
+          gcry_mpi_dump (public);
+          log_printf ("\n");
+        }
+
+      result = NULL;
+      fingerprint_from_pk (pk, fp, &fpn);
+      if (fpn != 20)
+        rc = gpg_error (GPG_ERR_INV_LENGTH);
+      else
+        rc = pk_ecdh_encrypt_with_shared_point (1 /*=encrypton*/,
+                                                shared, nshared,
+                                                fp, data, pkey, &result);
+      xfree (shared);
+      if (!rc)
+        {
+          resarr[0] = public;
+          resarr[1] = result;
+        }
+      else
+        {
+          gcry_mpi_release (public);
+          gcry_mpi_release (result);
+        }
+    }
+  else /* Elgamal or RSA case.  */
+    { /* Fixme: Add better error handling or make gnupg use
+         S-expressions directly.  */
+      resarr[0] = get_mpi_from_sexp (s_ciph, "a", GCRYMPI_FMT_USG);
+      if (!is_RSA (algo))
+        resarr[1] = get_mpi_from_sexp (s_ciph, "b", GCRYMPI_FMT_USG);
+    }
+
+ leave:
+  gcry_sexp_release (s_ciph);
+  return rc;
+}
+
+
+/* Check whether SKEY is a suitable secret key. */
+int
+pk_check_secret_key (pubkey_algo_t pkalgo, gcry_mpi_t *skey)
+{
+  gcry_sexp_t s_skey;
+  int rc;
+
+  if (pkalgo == PUBKEY_ALGO_DSA)
+    {
+      rc = gcry_sexp_build (&s_skey, NULL,
+			    "(private-key(dsa(p%m)(q%m)(g%m)(y%m)(x%m)))",
+			    skey[0], skey[1], skey[2], skey[3], skey[4]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_ELGAMAL || pkalgo == PUBKEY_ALGO_ELGAMAL_E)
+    {
+      rc = gcry_sexp_build (&s_skey, NULL,
+			    "(private-key(elg(p%m)(g%m)(y%m)(x%m)))",
+			    skey[0], skey[1], skey[2], skey[3]);
+    }
+  else if (is_RSA (pkalgo))
+    {
+      rc = gcry_sexp_build (&s_skey, NULL,
+			    "(private-key(rsa(n%m)(e%m)(d%m)(p%m)(q%m)(u%m)))",
+			    skey[0], skey[1], skey[2], skey[3], skey[4],
+			    skey[5]);
+    }
+  else if (pkalgo == PUBKEY_ALGO_ECDSA || pkalgo == PUBKEY_ALGO_ECDH)
+    {
+      char *curve = openpgp_oid_to_str (skey[0]);
+      if (!curve)
+        rc = gpg_error_from_syserror ();
+      else
+        {
+          rc = gcry_sexp_build (&s_skey, NULL,
+                                "(private-key(ecc(curve%s)(q%m)(d%m)))",
+                                curve, skey[1], skey[2]);
+          xfree (curve);
+        }
+    }
+  else if (pkalgo == PUBKEY_ALGO_EDDSA)
+    {
+      char *curve = openpgp_oid_to_str (skey[0]);
+      if (!curve)
+        rc = gpg_error_from_syserror ();
+      else
+        {
+          rc = gcry_sexp_build (&s_skey, NULL,
+                                "(private-key(ecc(curve %s)"
+                                "(flags eddsa)(q%m)(d%m)))",
+                                curve, skey[1], skey[2]);
+          xfree (curve);
+        }
+    }
+  else
+    return GPG_ERR_PUBKEY_ALGO;
+
+  if (!rc)
+    {
+      rc = gcry_pk_testkey (s_skey);
+      gcry_sexp_release (s_skey);
+    }
+  return rc;
+}