mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
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452890093d
When per-buffer-padding is FALSE, the OpenSSL context needs to be told to remove any padding at the end of the ciphertext Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/1243 Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3406>
624 lines
20 KiB
C
624 lines
20 KiB
C
/*
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* GStreamer gstreamer-aesdec
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*
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* Copyright, LCC (C) 2015 RidgeRun, LCC <carsten.behling@ridgerun.com>
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* Copyright, LCC (C) 2016 RidgeRun, LCC <jose.jimenez@ridgerun.com>
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* Copyright (C) 2020 Nice, Contact: Rabindra Harlalka <Rabindra.Harlalka@nice.com>
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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* DEALINGS IN THE SOFTWARE.
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*
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* Alternatively, the contents of this file may be used under the
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* GNU Lesser General Public License Version 2.1 (the "LGPL"), in
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* which case the following provisions apply instead of the ones
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* mentioned above:
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library 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 GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
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* Boston, MA 02110-1335, USA.
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*/
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/**
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* SECTION:element-aesdec
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*
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* AES decryption
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*
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* ## Example
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*
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* |[
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* echo "This is an AES crypto test ... " > plain.txt && \
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* gst-launch-1.0 filesrc location=plain.txt ! \
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* aesenc key=1f9423681beb9a79215820f6bda73d0f iv=e9aa8e834d8d70b7e0d254ff670dd718 ! \
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* aesdec key=1f9423681beb9a79215820f6bda73d0f iv=e9aa8e834d8d70b7e0d254ff670dd718 ! \
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* filesink location=dec.txt && \
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* cat dec.txt
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*
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* ]|
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*
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* Since: 1.20
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*/
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#ifdef HAVE_CONFIG_H
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# include <config.h>
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#endif
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#include <gst/gst.h>
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#include <gst/base/gstbasetransform.h>
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#include <string.h>
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#include "gstaeshelper.h"
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#include "gstaesdec.h"
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GST_DEBUG_CATEGORY_STATIC (gst_aes_dec_debug);
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#define GST_CAT_DEFAULT gst_aes_dec_debug
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G_DEFINE_TYPE_WITH_CODE (GstAesDec, gst_aes_dec, GST_TYPE_BASE_TRANSFORM,
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GST_DEBUG_CATEGORY_INIT (gst_aes_dec_debug, "aesdec", 0,
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"aesdec AES decryption element")
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);
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GST_ELEMENT_REGISTER_DEFINE (aesdec, "aesdec", GST_RANK_PRIMARY,
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GST_TYPE_AES_DEC);
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static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
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GST_PAD_SINK,
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GST_PAD_ALWAYS,
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GST_STATIC_CAPS ("ANY")
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);
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static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
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GST_PAD_SRC,
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GST_PAD_ALWAYS,
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GST_STATIC_CAPS ("ANY")
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);
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static void gst_aes_dec_set_property (GObject * object, guint prop_id,
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const GValue * value, GParamSpec * pspec);
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static void gst_aes_dec_get_property (GObject * object, guint prop_id,
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GValue * value, GParamSpec * pspec);
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static GstFlowReturn gst_aes_dec_transform (GstBaseTransform * base,
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GstBuffer * inbuf, GstBuffer * outbuf);
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static GstFlowReturn gst_aes_dec_prepare_output_buffer (GstBaseTransform * base,
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GstBuffer * inbuf, GstBuffer ** outbuf);
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static gboolean
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gst_aes_dec_sink_event (GstBaseTransform * base, GstEvent * event);
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static gboolean gst_aes_dec_start (GstBaseTransform * base);
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static gboolean gst_aes_dec_stop (GstBaseTransform * base);
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/* aes_dec helper functions */
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static gboolean gst_aes_dec_openssl_init (GstAesDec * filter);
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static gboolean gst_aes_dec_init_cipher (GstAesDec * filter);
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static void gst_aes_dec_finalize (GObject * object);
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/* GObject vmethod implementations */
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/* initialize class */
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static void
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gst_aes_dec_class_init (GstAesDecClass * klass)
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{
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GObjectClass *gobject_class;
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GstElementClass *gstelement_class;
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gobject_class = (GObjectClass *) klass;
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gstelement_class = (GstElementClass *) klass;
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gobject_class->set_property = gst_aes_dec_set_property;
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gobject_class->get_property = gst_aes_dec_get_property;
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gobject_class->finalize = gst_aes_dec_finalize;
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gst_type_mark_as_plugin_api (GST_TYPE_AES_CIPHER, 0);
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/**
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* GstAesDec:cipher
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*
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* AES cipher mode (key length and mode)
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* Currently, 128 and 256 bit keys are supported,
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* in "cipher block chaining" (CBC) mode
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*
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* Since: 1.20
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*/
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g_object_class_install_property (gobject_class, PROP_CIPHER,
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g_param_spec_enum ("cipher",
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"Cipher",
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"cipher mode",
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GST_TYPE_AES_CIPHER, GST_AES_DEFAULT_CIPHER_MODE,
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(G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
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GST_PARAM_MUTABLE_READY)));
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/**
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* GstAesDec:serialize-iv
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*
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* If true, read initialization vector from first 16 bytes of first buffer
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*
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* Since: 1.20
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*/
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g_object_class_install_property (gobject_class, PROP_SERIALIZE_IV,
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g_param_spec_boolean ("serialize-iv", "Serialize IV",
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"Read initialization vector from first 16 bytes of first buffer",
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GST_AES_DEFAULT_SERIALIZE_IV,
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G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
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/**
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* GstAesDec:per-buffer-padding
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*
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* If true, each buffer will be padded using PKCS7 padding
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* If false, only the final buffer in the stream will be padded
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* (by OpenSSL) using PKCS7
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*
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* Since: 1.20
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*/
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g_object_class_install_property (gobject_class, PROP_PER_BUFFER_PADDING,
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g_param_spec_boolean ("per-buffer-padding", "Per buffer padding",
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"If true, pad each buffer using PKCS7 padding scheme. Otherwise, only"
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"pad final buffer",
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GST_AES_PER_BUFFER_PADDING_DEFAULT,
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G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
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/**
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* GstAesDec:key
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*
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* AES encryption key (hexadecimal)
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*
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* Since: 1.20
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*/
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g_object_class_install_property (gobject_class, PROP_KEY,
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g_param_spec_string ("key", "Key",
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"AES encryption key (in hexadecimal). Length (in bytes) must be equivalent to "
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"the number of bits in the key length : "
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"16 bytes for AES 128 and 32 bytes for AES 256",
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(gchar *) GST_AES_DEFAULT_KEY,
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G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
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/**
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* GstAesDec:iv
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*
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* AES encryption initialization vector (hexadecimal)
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*
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* Since: 1.20
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*/
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g_object_class_install_property (gobject_class, PROP_IV,
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g_param_spec_string ("iv", "Iv",
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"AES encryption initialization vector (in hexadecimal). "
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"Length must equal AES block length (16 bytes)",
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(gchar *) GST_AES_DEFAULT_IV,
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G_PARAM_READWRITE | GST_PARAM_MUTABLE_READY));
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gst_element_class_set_details_simple (gstelement_class,
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"aesdec",
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"Generic/Filter",
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"AES buffer decryption",
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"Rabindra Harlalka <Rabindra.Harlalka@nice.com>");
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gst_element_class_add_pad_template (gstelement_class,
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gst_static_pad_template_get (&src_template));
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gst_element_class_add_pad_template (gstelement_class,
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gst_static_pad_template_get (&sink_template));
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GST_BASE_TRANSFORM_CLASS (klass)->transform =
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GST_DEBUG_FUNCPTR (gst_aes_dec_transform);
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GST_BASE_TRANSFORM_CLASS (klass)->prepare_output_buffer =
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GST_DEBUG_FUNCPTR (gst_aes_dec_prepare_output_buffer);
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GST_BASE_TRANSFORM_CLASS (klass)->start =
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GST_DEBUG_FUNCPTR (gst_aes_dec_start);
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GST_BASE_TRANSFORM_CLASS (klass)->sink_event =
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GST_DEBUG_FUNCPTR (gst_aes_dec_sink_event);
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GST_BASE_TRANSFORM_CLASS (klass)->stop = GST_DEBUG_FUNCPTR (gst_aes_dec_stop);
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}
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/* Initialize element
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*/
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static void
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gst_aes_dec_init (GstAesDec * filter)
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{
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GST_INFO_OBJECT (filter, "Initializing plugin");
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filter->cipher = GST_AES_DEFAULT_CIPHER_MODE;
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filter->awaiting_first_buffer = TRUE;
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filter->per_buffer_padding = GST_AES_PER_BUFFER_PADDING_DEFAULT;
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g_mutex_init (&filter->decoder_lock);
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}
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static void
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gst_aes_dec_finalize (GObject * object)
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{
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GstAesDec *filter = GST_AES_DEC (object);
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g_mutex_clear (&filter->decoder_lock);
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G_OBJECT_CLASS (gst_aes_dec_parent_class)->finalize (object);
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}
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static void
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gst_aes_dec_set_property (GObject * object, guint prop_id,
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const GValue * value, GParamSpec * pspec)
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{
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GstAesDec *filter = GST_AES_DEC (object);
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g_mutex_lock (&filter->decoder_lock);
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/* no property may be set after first output buffer is prepared */
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if (filter->locked_properties) {
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GST_WARNING_OBJECT (filter,
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"Properties cannot be set once buffers begin flowing in element. Ignored");
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goto cleanup;
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}
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switch (prop_id) {
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case PROP_CIPHER:
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filter->cipher = g_value_get_enum (value);
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filter->evp_cipher =
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EVP_get_cipherbyname (gst_aes_cipher_enum_to_string (filter->cipher));
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GST_DEBUG_OBJECT (filter, "cipher: %s",
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gst_aes_cipher_enum_to_string (filter->cipher));
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break;
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case PROP_SERIALIZE_IV:
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filter->serialize_iv = g_value_get_boolean (value);
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GST_DEBUG_OBJECT (filter, "serialize iv: %s",
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filter->serialize_iv ? "TRUE" : "FALSE");
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break;
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case PROP_PER_BUFFER_PADDING:
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filter->per_buffer_padding = g_value_get_boolean (value);
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GST_DEBUG_OBJECT (filter, "Per buffer padding: %s",
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filter->per_buffer_padding ? "TRUE" : "FALSE");
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break;
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case PROP_KEY:
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{
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guint hex_len = gst_aes_hexstring2bytearray (GST_ELEMENT (filter),
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g_value_get_string (value), filter->key);
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if (!hex_len) {
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GST_ERROR_OBJECT (filter, "invalid key");
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goto cleanup;
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}
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GST_DEBUG_OBJECT (filter, "key: %s", g_value_get_string (value));
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}
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break;
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case PROP_IV:
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{
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gchar iv_string[2 * GST_AES_BLOCK_SIZE + 1];
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guint hex_len = gst_aes_hexstring2bytearray (GST_ELEMENT (filter),
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g_value_get_string (value), filter->iv);
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if (hex_len != GST_AES_BLOCK_SIZE) {
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GST_ERROR_OBJECT (filter, "invalid initialization vector");
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goto cleanup;
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}
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GST_DEBUG_OBJECT (filter, "iv: %s",
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gst_aes_bytearray2hexstring (filter->iv, iv_string,
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GST_AES_BLOCK_SIZE));
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}
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break;
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default:
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G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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break;
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}
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cleanup:
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g_mutex_unlock (&filter->decoder_lock);
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}
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static void
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gst_aes_dec_get_property (GObject * object, guint prop_id,
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GValue * value, GParamSpec * pspec)
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{
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GstAesDec *filter = GST_AES_DEC (object);
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switch (prop_id) {
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case PROP_CIPHER:
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g_value_set_enum (value, filter->cipher);
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break;
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case PROP_SERIALIZE_IV:
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g_value_set_boolean (value, filter->serialize_iv);
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break;
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case PROP_PER_BUFFER_PADDING:
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g_value_set_boolean (value, filter->per_buffer_padding);
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break;
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case PROP_KEY:
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g_value_set_string (value, (gchar *) filter->key);
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break;
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case PROP_IV:
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g_value_set_string (value, (gchar *) filter->iv);
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break;
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default:
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G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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break;
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}
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}
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static gboolean
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gst_aes_dec_sink_event (GstBaseTransform * base, GstEvent * event)
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{
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GstAesDec *filter = GST_AES_DEC (base);
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g_mutex_lock (&filter->decoder_lock);
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if (GST_EVENT_TYPE (event) == GST_EVENT_EOS) {
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GST_DEBUG_OBJECT (filter, "Received EOS on sink pad");
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if (!filter->per_buffer_padding && !filter->awaiting_first_buffer) {
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GstBuffer *outbuf = NULL;
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gint len;
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GstMapInfo outmap;
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outbuf = gst_buffer_new_allocate (NULL, EVP_MAX_BLOCK_LENGTH, NULL);
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if (outbuf == NULL) {
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GST_DEBUG_OBJECT (filter,
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"Failed to allocate a new buffer of length %d",
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EVP_MAX_BLOCK_LENGTH);
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goto buffer_fail;
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}
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if (!gst_buffer_map (outbuf, &outmap, GST_MAP_WRITE)) {
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GST_DEBUG_OBJECT (filter,
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"gst_buffer_map on outbuf failed for final buffer.");
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gst_buffer_unref (outbuf);
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goto buffer_fail;
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}
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if (1 != EVP_CipherFinal_ex (filter->evp_ctx, outmap.data, &len)) {
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GST_DEBUG_OBJECT (filter, "Could not finalize openssl encryption");
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gst_buffer_unmap (outbuf, &outmap);
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gst_buffer_unref (outbuf);
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goto cipher_fail;
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}
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if (len == 0) {
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GST_DEBUG_OBJECT (filter, "Not pushing final buffer as length is 0");
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gst_buffer_unmap (outbuf, &outmap);
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gst_buffer_unref (outbuf);
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goto out;
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}
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GST_DEBUG_OBJECT (filter, "Pushing final buffer of length: %d", len);
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gst_buffer_unmap (outbuf, &outmap);
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gst_buffer_set_size (outbuf, len);
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if (gst_pad_push (base->srcpad, outbuf) != GST_FLOW_OK) {
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GST_DEBUG_OBJECT (filter, "Failed to push the final buffer");
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goto push_fail;
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}
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} else {
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GST_DEBUG_OBJECT (filter,
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"Not pushing final buffer as we didn't have any input");
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}
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}
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out:
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g_mutex_unlock (&filter->decoder_lock);
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return GST_BASE_TRANSFORM_CLASS (gst_aes_dec_parent_class)->sink_event (base,
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event);
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/* ERROR */
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buffer_fail:
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GST_ELEMENT_ERROR (filter, RESOURCE, FAILED, (NULL),
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("Failed to allocate or map buffer for writing"));
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g_mutex_unlock (&filter->decoder_lock);
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return FALSE;
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cipher_fail:
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GST_ELEMENT_ERROR (filter, STREAM, FAILED, ("Cipher finalization failed."),
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("Error while finalizing the stream"));
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g_mutex_unlock (&filter->decoder_lock);
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return FALSE;
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push_fail:
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GST_ELEMENT_ERROR (filter, CORE, PAD, (NULL),
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("Failed to push the final buffer"));
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g_mutex_unlock (&filter->decoder_lock);
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return FALSE;
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}
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/* GstBaseTransform vmethod implementations */
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static GstFlowReturn
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gst_aes_dec_transform (GstBaseTransform * base,
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GstBuffer * inbuf, GstBuffer * outbuf)
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{
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GstAesDec *filter = GST_AES_DEC (base);
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GstFlowReturn ret = GST_FLOW_ERROR;
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GstMapInfo inmap, outmap;
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guchar *ciphertext;
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gint ciphertext_len;
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guchar *plaintext;
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gint plaintext_len;
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guint padding = 0;
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if (!gst_buffer_map (inbuf, &inmap, GST_MAP_READ)) {
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GST_ELEMENT_ERROR (filter, RESOURCE, FAILED, (NULL),
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("Failed to map buffer for reading"));
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goto cleanup;
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}
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if (!gst_buffer_map (outbuf, &outmap, GST_MAP_WRITE)) {
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gst_buffer_unmap (inbuf, &inmap);
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GST_ELEMENT_ERROR (filter, RESOURCE, FAILED, (NULL),
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("Failed to map buffer for writing"));
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goto cleanup;
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}
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/* DECRYPTING */
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ciphertext = inmap.data;
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ciphertext_len = gst_buffer_get_size (inbuf);
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if (filter->awaiting_first_buffer) {
|
|
if (filter->serialize_iv) {
|
|
gchar iv_string[2 * GST_AES_BLOCK_SIZE + 1];
|
|
|
|
if (ciphertext_len < GST_AES_BLOCK_SIZE) {
|
|
GST_ELEMENT_ERROR (filter, RESOURCE, FAILED, (NULL),
|
|
("Cipher text too short"));
|
|
goto cleanup;
|
|
}
|
|
memcpy (filter->iv, ciphertext, GST_AES_BLOCK_SIZE);
|
|
GST_DEBUG_OBJECT (filter, "read serialized iv: %s",
|
|
gst_aes_bytearray2hexstring (filter->iv, iv_string,
|
|
GST_AES_BLOCK_SIZE));
|
|
ciphertext += GST_AES_BLOCK_SIZE;
|
|
ciphertext_len -= GST_AES_BLOCK_SIZE;
|
|
}
|
|
if (!gst_aes_dec_init_cipher (filter)) {
|
|
GST_ELEMENT_ERROR (filter, RESOURCE, FAILED, (NULL),
|
|
("Failed to initialize cipher"));
|
|
goto cleanup;
|
|
}
|
|
}
|
|
plaintext = outmap.data;
|
|
|
|
if (!EVP_CipherUpdate (filter->evp_ctx, plaintext,
|
|
&plaintext_len, ciphertext, ciphertext_len)) {
|
|
GST_ELEMENT_ERROR (filter, STREAM, FAILED, ("Cipher update failed."),
|
|
("Error while updating openssl cipher"));
|
|
goto cleanup;
|
|
} else {
|
|
if (filter->per_buffer_padding) {
|
|
gint k;
|
|
|
|
/* sanity check on padding value */
|
|
padding = plaintext[plaintext_len - 1];
|
|
if (padding == 0 || padding > GST_AES_BLOCK_SIZE) {
|
|
GST_ELEMENT_ERROR (filter, STREAM, FAILED, ("Corrupt cipher text."),
|
|
("Illegal PKCS7 padding value %d", padding));
|
|
goto cleanup;
|
|
}
|
|
for (k = 1; k < padding; ++k) {
|
|
if (plaintext[plaintext_len - 1 - k] != padding) {
|
|
GST_ELEMENT_ERROR (filter, STREAM, FAILED, ("Corrupt cipher text."),
|
|
("PKCS7 padding values must all be equal"));
|
|
goto cleanup;
|
|
}
|
|
}
|
|
/* remove padding (final block padding) */
|
|
plaintext_len -= padding;
|
|
}
|
|
if (plaintext_len > 2 * GST_AES_BLOCK_SIZE)
|
|
GST_MEMDUMP ("First 32 bytes of plain text", plaintext,
|
|
2 * GST_AES_BLOCK_SIZE);
|
|
}
|
|
gst_buffer_unmap (inbuf, &inmap);
|
|
gst_buffer_unmap (outbuf, &outmap);
|
|
|
|
GST_LOG_OBJECT (filter,
|
|
"Ciphertext len: %d, Plaintext len: %d, Padding: %d",
|
|
ciphertext_len, plaintext_len, padding);
|
|
gst_buffer_set_size (outbuf, plaintext_len);
|
|
ret = GST_FLOW_OK;
|
|
|
|
cleanup:
|
|
filter->awaiting_first_buffer = FALSE;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static GstFlowReturn
|
|
gst_aes_dec_prepare_output_buffer (GstBaseTransform * base,
|
|
GstBuffer * inbuf, GstBuffer ** outbuf)
|
|
{
|
|
GstAesDec *filter = GST_AES_DEC (base);
|
|
GstBaseTransformClass *bclass = GST_BASE_TRANSFORM_GET_CLASS (base);
|
|
guint out_size;
|
|
|
|
g_mutex_lock (&filter->decoder_lock);
|
|
filter->locked_properties = TRUE;
|
|
/* we need extra space at end of output buffer
|
|
* when we let OpenSSL handle PKCS7 padding */
|
|
out_size = (gint) gst_buffer_get_size (inbuf) +
|
|
(!filter->per_buffer_padding ? GST_AES_BLOCK_SIZE : 0);
|
|
|
|
/* Since serialized IV is stripped from first buffer,
|
|
* reduce output buffer size by GST_AES_BLOCK_SIZE in this case */
|
|
if (filter->serialize_iv && filter->awaiting_first_buffer) {
|
|
g_assert (gst_buffer_get_size (inbuf) > GST_AES_BLOCK_SIZE);
|
|
out_size -= GST_AES_BLOCK_SIZE;
|
|
}
|
|
g_mutex_unlock (&filter->decoder_lock);
|
|
|
|
*outbuf = gst_buffer_new_allocate (NULL, out_size, NULL);
|
|
GST_LOG_OBJECT (filter,
|
|
"Input buffer size %d,\nAllocating output buffer size: %d",
|
|
(gint) gst_buffer_get_size (inbuf), out_size);
|
|
bclass->copy_metadata (base, inbuf, *outbuf);
|
|
|
|
return GST_FLOW_OK;
|
|
}
|
|
|
|
static gboolean
|
|
gst_aes_dec_start (GstBaseTransform * base)
|
|
{
|
|
GstAesDec *filter = GST_AES_DEC (base);
|
|
|
|
GST_INFO_OBJECT (filter, "Starting");
|
|
if (!gst_aes_dec_openssl_init (filter)) {
|
|
GST_ERROR_OBJECT (filter, "OpenSSL initialization failed");
|
|
return FALSE;
|
|
}
|
|
|
|
if (!filter->serialize_iv) {
|
|
if (!gst_aes_dec_init_cipher (filter))
|
|
return FALSE;
|
|
}
|
|
GST_INFO_OBJECT (filter, "Start successful");
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
gst_aes_dec_init_cipher (GstAesDec * filter)
|
|
{
|
|
if (!EVP_CipherInit_ex (filter->evp_ctx, filter->evp_cipher, NULL,
|
|
filter->key, filter->iv, FALSE)) {
|
|
GST_ERROR_OBJECT (filter, "Could not initialize openssl cipher");
|
|
return FALSE;
|
|
}
|
|
if (!EVP_CIPHER_CTX_set_padding (filter->evp_ctx,
|
|
filter->per_buffer_padding ? 0 : 1)) {
|
|
GST_ERROR_OBJECT (filter, "Could not set padding");
|
|
return FALSE;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
gst_aes_dec_stop (GstBaseTransform * base)
|
|
{
|
|
GstAesDec *filter = GST_AES_DEC (base);
|
|
|
|
GST_INFO_OBJECT (filter, "Stopping");
|
|
EVP_CIPHER_CTX_free (filter->evp_ctx);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/* AesDec helper functions */
|
|
static gboolean
|
|
gst_aes_dec_openssl_init (GstAesDec * filter)
|
|
{
|
|
GST_DEBUG_OBJECT (filter, "Initializing with %s",
|
|
OpenSSL_version (OPENSSL_VERSION));
|
|
|
|
filter->evp_cipher =
|
|
EVP_get_cipherbyname (gst_aes_cipher_enum_to_string (filter->cipher));
|
|
if (!filter->evp_cipher) {
|
|
GST_ERROR_OBJECT (filter, "Could not get cipher by name from openssl");
|
|
return FALSE;
|
|
}
|
|
if (!(filter->evp_ctx = EVP_CIPHER_CTX_new ()))
|
|
return FALSE;
|
|
GST_LOG_OBJECT (filter, "Initialization successful");
|
|
|
|
return TRUE;
|
|
}
|