diff options
| -rw-r--r-- | g10/pkglue.c | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/g10/pkglue.c b/g10/pkglue.c index a9d4d8549..1fa0fc4dd 100644 --- a/g10/pkglue.c +++ b/g10/pkglue.c @@ -717,6 +717,10 @@ do_encrypt_ecdh (PKT_public_key *pk, gcry_mpi_t data, gcry_mpi_t *resarr) unsigned char ecc_ct[ECC_POINT_LEN_MAX]; unsigned char ecc_ecdh[ECC_POINT_LEN_MAX]; size_t ecc_ct_len, ecc_ecdh_len; + const char *shared_secret; + size_t shared_secretlen; + const char *ephemeral_pubkey; + size_t ephemeral_pubkeylen; unsigned char *kek = NULL; size_t kek_len; @@ -808,6 +812,30 @@ do_encrypt_ecdh (PKT_public_key *pk, gcry_mpi_t data, gcry_mpi_t *resarr) log_printhex (ecc_ecdh, ecc_ecdh_len, "ECC ecdh:"); } + if (ecc->is_weierstrauss) + { + shared_secret = ecc_ecdh + 1; + shared_secretlen = (ecc_ecdh_len - 1) / 2; + ephemeral_pubkey = ecc_ct; + ephemeral_pubkeylen = ecc_ct_len; + } + else + { + shared_secret = ecc_ecdh; + shared_secretlen = ecc_ecdh_len; + + if (ecc->may_have_prefix) + { + ephemeral_pubkeylen = ecc_ct_len + 1; + memmove (ecc_ct + 1, ecc_ct, ecc_ct_len); + ecc_ct[0] = 0x40; + } + else + ephemeral_pubkeylen = ecc_ct_len; + + ephemeral_pubkey = ecc_ct; + } + err = ecc_build_kdf_params (&kdf_params, &kdf_params_len, &kdf_params_spec, pk->pkey, fp); if (err) @@ -852,10 +880,7 @@ do_encrypt_ecdh (PKT_public_key *pk, gcry_mpi_t data, gcry_mpi_t *resarr) } err = gnupg_ecc_kem_kdf (kek, kek_len, 1, kdf_hash_algo, - ecc->is_weierstrauss ? - ecc_ecdh + 1 : ecc_ecdh, - ecc->is_weierstrauss ? - (ecc_ecdh_len - 1) / 2 : ecc_ecdh_len, + shared_secret, shared_secretlen, kdf_params, kdf_params_len); xfree (kdf_params); if (err) @@ -902,7 +927,8 @@ do_encrypt_ecdh (PKT_public_key *pk, gcry_mpi_t data, gcry_mpi_t *resarr) if (DBG_CRYPTO) log_printhex (enc_seskey, enc_seskey_len, "enc_seskey:"); - resarr[0] = gcry_mpi_set_opaque_copy (NULL, ecc_ct, 8 * ecc_ct_len); + resarr[0] = gcry_mpi_set_opaque_copy (NULL, ephemeral_pubkey, + 8 * ephemeral_pubkeylen); if (!resarr[0]) { err = gpg_error_from_syserror (); |