2015-10-16 00:33:37 +00:00
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
< html xmlns = "http://www.w3.org/1999/xhtml" >
< head >
< meta http-equiv = "Content-Type" content = "text/xhtml;charset=UTF-8" / >
< meta http-equiv = "X-UA-Compatible" content = "IE=9" / >
< meta name = "generator" content = "Doxygen 1.8.6" / >
< title > DASH Media Packaging SDK: media/base/aes_encryptor.cc Source File< / title >
< link href = "../../tabs.css" rel = "stylesheet" type = "text/css" / >
< script type = "text/javascript" src = "../../jquery.js" > < / script >
< script type = "text/javascript" src = "../../dynsections.js" > < / script >
< link href = "../../search/search.css" rel = "stylesheet" type = "text/css" / >
< script type = "text/javascript" src = "../../search/search.js" > < / script >
< script type = "text/javascript" >
$(document).ready(function() { searchBox.OnSelectItem(0); });
< / script >
< link href = "../../doxygen.css" rel = "stylesheet" type = "text/css" / >
< / head >
< body >
< div id = "top" > <!-- do not remove this div, it is closed by doxygen! -->
< div id = "titlearea" >
< table cellspacing = "0" cellpadding = "0" >
< tbody >
< tr style = "height: 56px;" >
< td style = "padding-left: 0.5em;" >
< div id = "projectname" > DASH Media Packaging SDK
< / div >
< / td >
< / tr >
< / tbody >
< / table >
< / div >
<!-- end header part -->
<!-- Generated by Doxygen 1.8.6 -->
< script type = "text/javascript" >
var searchBox = new SearchBox("searchBox", "../../search",false,'Search');
< / script >
< div id = "navrow1" class = "tabs" >
< ul class = "tablist" >
< li > < a href = "../../index.html" > < span > Main  Page< / span > < / a > < / li >
< li > < a href = "../../namespaces.html" > < span > Namespaces< / span > < / a > < / li >
< li > < a href = "../../annotated.html" > < span > Classes< / span > < / a > < / li >
< li class = "current" > < a href = "../../files.html" > < span > Files< / span > < / a > < / li >
< li >
< div id = "MSearchBox" class = "MSearchBoxInactive" >
< span class = "left" >
< img id = "MSearchSelect" src = "../../search/mag_sel.png"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
alt=""/>
< input type = "text" id = "MSearchField" value = "Search" accesskey = "S"
onfocus="searchBox.OnSearchFieldFocus(true)"
onblur="searchBox.OnSearchFieldFocus(false)"
onkeyup="searchBox.OnSearchFieldChange(event)"/>
< / span > < span class = "right" >
< a id = "MSearchClose" href = "javascript:searchBox.CloseResultsWindow()" > < img id = "MSearchCloseImg" border = "0" src = "../../search/close.png" alt = "" / > < / a >
< / span >
< / div >
< / li >
< / ul >
< / div >
< div id = "navrow2" class = "tabs2" >
< ul class = "tablist" >
< li > < a href = "../../files.html" > < span > File  List< / span > < / a > < / li >
< / ul >
< / div >
<!-- window showing the filter options -->
< div id = "MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
2015-10-19 19:22:31 +00:00
< a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(0)" > < span class = "SelectionMark" >   < / span > All< / a > < a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(1)" > < span class = "SelectionMark" >   < / span > Classes< / a > < a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(2)" > < span class = "SelectionMark" >   < / span > Namespaces< / a > < a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(3)" > < span class = "SelectionMark" >   < / span > Functions< / a > < a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(4)" > < span class = "SelectionMark" >   < / span > Variables< / a > < a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(5)" > < span class = "SelectionMark" >   < / span > Typedefs< / a > < a class = "SelectItem" href = "javascript:void(0)" onclick = "searchBox.OnSelectItem(6)" > < span class = "SelectionMark" >   < / span > Enumerator< / a > < / div >
2015-10-16 00:33:37 +00:00
<!-- iframe showing the search results (closed by default) -->
< div id = "MSearchResultsWindow" >
< iframe src = "javascript:void(0)" frameborder = "0"
name="MSearchResults" id="MSearchResults">
< / iframe >
< / div >
< div id = "nav-path" class = "navpath" >
< ul >
< li class = "navelem" > < a class = "el" href = "../../dir_39dc0668bd5a501998f94e8b4e546c71.html" > media< / a > < / li > < li class = "navelem" > < a class = "el" href = "../../dir_c6ada2450b25ab5438a4dba6c9b890af.html" > base< / a > < / li > < / ul >
< / div >
< / div > <!-- top -->
< div class = "header" >
< div class = "headertitle" >
< div class = "title" > aes_encryptor.cc< / div > < / div >
< / div > <!-- header -->
< div class = "contents" >
< div class = "fragment" > < div class = "line" > < a name = "l00001" > < / a > < span class = "lineno" > 1< / span >   < span class = "comment" > // Copyright 2014 Google Inc. All rights reserved.< / span > < / div >
< div class = "line" > < a name = "l00002" > < / a > < span class = "lineno" > 2< / span >   < span class = "comment" > //< / span > < / div >
< div class = "line" > < a name = "l00003" > < / a > < span class = "lineno" > 3< / span >   < span class = "comment" > // Use of this source code is governed by a BSD-style< / span > < / div >
< div class = "line" > < a name = "l00004" > < / a > < span class = "lineno" > 4< / span >   < span class = "comment" > // license that can be found in the LICENSE file or at< / span > < / div >
< div class = "line" > < a name = "l00005" > < / a > < span class = "lineno" > 5< / span >   < span class = "comment" > // https://developers.google.com/open-source/licenses/bsd< / span > < / div >
< div class = "line" > < a name = "l00006" > < / a > < span class = "lineno" > 6< / span >   < / div >
< div class = "line" > < a name = "l00007" > < / a > < span class = "lineno" > 7< / span >   < span class = "preprocessor" > #include " packager/media/base/aes_encryptor.h" < / span > < / div >
< div class = "line" > < a name = "l00008" > < / a > < span class = "lineno" > 8< / span >   < / div >
< div class = "line" > < a name = "l00009" > < / a > < span class = "lineno" > 9< / span >   < span class = "preprocessor" > #include < openssl/aes.h> < / span > < / div >
< div class = "line" > < a name = "l00010" > < / a > < span class = "lineno" > 10< / span >   < span class = "preprocessor" > #include < openssl/err.h> < / span > < / div >
< div class = "line" > < a name = "l00011" > < / a > < span class = "lineno" > 11< / span >   < span class = "preprocessor" > #include < openssl/rand.h> < / span > < / div >
< div class = "line" > < a name = "l00012" > < / a > < span class = "lineno" > 12< / span >   < / div >
< div class = "line" > < a name = "l00013" > < / a > < span class = "lineno" > 13< / span >   < span class = "preprocessor" > #include " packager/base/logging.h" < / span > < / div >
< div class = "line" > < a name = "l00014" > < / a > < span class = "lineno" > 14< / span >   < / div >
< div class = "line" > < a name = "l00015" > < / a > < span class = "lineno" > 15< / span >   < span class = "keyword" > namespace < / span > {< / div >
< div class = "line" > < a name = "l00016" > < / a > < span class = "lineno" > 16< / span >   < / div >
< div class = "line" > < a name = "l00017" > < / a > < span class = "lineno" > 17< / span >   < span class = "comment" > // Increment an 8-byte counter by 1. Return true if overflowed.< / span > < / div >
< div class = "line" > < a name = "l00018" > < / a > < span class = "lineno" > 18< / span >   < span class = "keywordtype" > bool< / span > Increment64(uint8_t* counter) {< / div >
< div class = "line" > < a name = "l00019" > < / a > < span class = "lineno" > 19< / span >   DCHECK(counter);< / div >
< div class = "line" > < a name = "l00020" > < / a > < span class = "lineno" > 20< / span >   < span class = "keywordflow" > for< / span > (< span class = "keywordtype" > int< / span > i = 7; i > = 0; --i)< / div >
< div class = "line" > < a name = "l00021" > < / a > < span class = "lineno" > 21< / span >   < span class = "keywordflow" > if< / span > (++counter[i] != 0)< / div >
< div class = "line" > < a name = "l00022" > < / a > < span class = "lineno" > 22< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00023" > < / a > < span class = "lineno" > 23< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00024" > < / a > < span class = "lineno" > 24< / span >   }< / div >
< div class = "line" > < a name = "l00025" > < / a > < span class = "lineno" > 25< / span >   < / div >
< div class = "line" > < a name = "l00026" > < / a > < span class = "lineno" > 26< / span >   < span class = "comment" > // According to ISO/IEC FDIS 23001-7: CENC spec, IV should be either< / span > < / div >
< div class = "line" > < a name = "l00027" > < / a > < span class = "lineno" > 27< / span >   < span class = "comment" > // 64-bit (8-byte) or 128-bit (16-byte).< / span > < / div >
< div class = "line" > < a name = "l00028" > < / a > < span class = "lineno" > 28< / span >   < span class = "keywordtype" > bool< / span > IsIvSizeValid(< span class = "keywordtype" > size_t< / span > iv_size) { < span class = "keywordflow" > return< / span > iv_size == 8 || iv_size == 16; }< / div >
< div class = "line" > < a name = "l00029" > < / a > < span class = "lineno" > 29< / span >   < / div >
< div class = "line" > < a name = "l00030" > < / a > < span class = "lineno" > 30< / span >   < span class = "comment" > // AES defines three key sizes: 128, 192 and 256 bits.< / span > < / div >
< div class = "line" > < a name = "l00031" > < / a > < span class = "lineno" > 31< / span >   < span class = "keywordtype" > bool< / span > IsKeySizeValidForAes(< span class = "keywordtype" > size_t< / span > key_size) {< / div >
< div class = "line" > < a name = "l00032" > < / a > < span class = "lineno" > 32< / span >   < span class = "keywordflow" > return< / span > key_size == 16 || key_size == 24 || key_size == 32;< / div >
< div class = "line" > < a name = "l00033" > < / a > < span class = "lineno" > 33< / span >   }< / div >
< div class = "line" > < a name = "l00034" > < / a > < span class = "lineno" > 34< / span >   < / div >
< div class = "line" > < a name = "l00035" > < / a > < span class = "lineno" > 35< / span >   < span class = "comment" > // CENC protection scheme uses 128-bit keys in counter mode.< / span > < / div >
< div class = "line" > < a name = "l00036" > < / a > < span class = "lineno" > 36< / span >   < span class = "keyword" > const< / span > uint32_t kCencKeySize = 16;< / div >
< div class = "line" > < a name = "l00037" > < / a > < span class = "lineno" > 37< / span >   < / div >
< div class = "line" > < a name = "l00038" > < / a > < span class = "lineno" > 38< / span >   } < span class = "comment" > // namespace< / span > < / div >
< div class = "line" > < a name = "l00039" > < / a > < span class = "lineno" > 39< / span >   < / div >
< div class = "line" > < a name = "l00040" > < / a > < span class = "lineno" > 40< / span >   < span class = "keyword" > namespace < / span > edash_packager {< / div >
< div class = "line" > < a name = "l00041" > < / a > < span class = "lineno" > 41< / span >   < span class = "keyword" > namespace < / span > media {< / div >
< div class = "line" > < a name = "l00042" > < / a > < span class = "lineno" > 42< / span >   < / div >
< div class = "line" > < a name = "l00043" > < / a > < span class = "lineno" > 43< / span >   AesCtrEncryptor::AesCtrEncryptor()< / div >
< div class = "line" > < a name = "l00044" > < / a > < span class = "lineno" > 44< / span >   : block_offset_(0),< / div >
< div class = "line" > < a name = "l00045" > < / a > < span class = "lineno" > 45< / span >   encrypted_counter_(AES_BLOCK_SIZE, 0),< / div >
< div class = "line" > < a name = "l00046" > < / a > < span class = "lineno" > 46< / span >   counter_overflow_(false) {< / div >
< div class = "line" > < a name = "l00047" > < / a > < span class = "lineno" > 47< / span >   COMPILE_ASSERT(AES_BLOCK_SIZE == kCencKeySize,< / div >
< div class = "line" > < a name = "l00048" > < / a > < span class = "lineno" > 48< / span >   cenc_key_size_should_be_the_same_as_aes_block_size);< / div >
< div class = "line" > < a name = "l00049" > < / a > < span class = "lineno" > 49< / span >   }< / div >
< div class = "line" > < a name = "l00050" > < / a > < span class = "lineno" > 50< / span >   < / div >
< div class = "line" > < a name = "l00051" > < / a > < span class = "lineno" > 51< / span >   AesCtrEncryptor::~AesCtrEncryptor() {}< / div >
< div class = "line" > < a name = "l00052" > < / a > < span class = "lineno" > 52< / span >   < / div >
< div class = "line" > < a name = "l00053" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d79/classedash__packager_1_1media_1_1AesCtrEncryptor.html#a3d1c0717e1310823bd6827299b6050ef" > 53< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCtrEncryptor::InitializeWithRandomIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & key,< / div >
< div class = "line" > < a name = "l00054" > < / a > < span class = "lineno" > 54< / span >   uint8_t iv_size) {< / div >
< div class = "line" > < a name = "l00055" > < / a > < span class = "lineno" > 55< / span >   std::vector< uint8_t> iv(iv_size, 0);< / div >
< div class = "line" > < a name = "l00056" > < / a > < span class = "lineno" > 56< / span >   < span class = "keywordflow" > if< / span > (RAND_bytes(& iv[0], iv_size) != 1) {< / div >
< div class = "line" > < a name = "l00057" > < / a > < span class = "lineno" > 57< / span >   LOG(ERROR) < < < span class = "stringliteral" > " RAND_bytes failed with error: " < / span > < / div >
< div class = "line" > < a name = "l00058" > < / a > < span class = "lineno" > 58< / span >   < < ERR_error_string(ERR_get_error(), NULL);< / div >
< div class = "line" > < a name = "l00059" > < / a > < span class = "lineno" > 59< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00060" > < / a > < span class = "lineno" > 60< / span >   }< / div >
< div class = "line" > < a name = "l00061" > < / a > < span class = "lineno" > 61< / span >   < span class = "keywordflow" > return< / span > InitializeWithIv(key, iv);< / div >
< div class = "line" > < a name = "l00062" > < / a > < span class = "lineno" > 62< / span >   }< / div >
< div class = "line" > < a name = "l00063" > < / a > < span class = "lineno" > 63< / span >   < / div >
< div class = "line" > < a name = "l00064" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d79/classedash__packager_1_1media_1_1AesCtrEncryptor.html#a7e755a2bc06f35c8b3de9a7ab8b538cd" > 64< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCtrEncryptor::InitializeWithIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & key,< / div >
< div class = "line" > < a name = "l00065" > < / a > < span class = "lineno" > 65< / span >   < span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00066" > < / a > < span class = "lineno" > 66< / span >   < span class = "keywordflow" > if< / span > (key.size() != kCencKeySize) {< / div >
< div class = "line" > < a name = "l00067" > < / a > < span class = "lineno" > 67< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid key size of " < / span > < < key.size() < < < span class = "stringliteral" > " for CENC." < / span > ;< / div >
< div class = "line" > < a name = "l00068" > < / a > < span class = "lineno" > 68< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00069" > < / a > < span class = "lineno" > 69< / span >   }< / div >
< div class = "line" > < a name = "l00070" > < / a > < span class = "lineno" > 70< / span >   < span class = "keywordflow" > if< / span > (!IsIvSizeValid(iv.size())) {< / div >
< div class = "line" > < a name = "l00071" > < / a > < span class = "lineno" > 71< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00072" > < / a > < span class = "lineno" > 72< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00073" > < / a > < span class = "lineno" > 73< / span >   }< / div >
< div class = "line" > < a name = "l00074" > < / a > < span class = "lineno" > 74< / span >   < / div >
< div class = "line" > < a name = "l00075" > < / a > < span class = "lineno" > 75< / span >   aes_key_.reset(< span class = "keyword" > new< / span > AES_KEY());< / div >
< div class = "line" > < a name = "l00076" > < / a > < span class = "lineno" > 76< / span >   CHECK_EQ(AES_set_encrypt_key(& key[0], AES_BLOCK_SIZE * 8, aes_key_.get()), 0);< / div >
< div class = "line" > < a name = "l00077" > < / a > < span class = "lineno" > 77< / span >   < span class = "keywordflow" > return< / span > SetIv(iv);< / div >
< div class = "line" > < a name = "l00078" > < / a > < span class = "lineno" > 78< / span >   }< / div >
< div class = "line" > < a name = "l00079" > < / a > < span class = "lineno" > 79< / span >   < / div >
< div class = "line" > < a name = "l00080" > < / a > < span class = "lineno" > 80< / span >   < span class = "keywordtype" > bool< / span > AesCtrEncryptor::Encrypt(< span class = "keyword" > const< / span > uint8_t* plaintext,< / div >
< div class = "line" > < a name = "l00081" > < / a > < span class = "lineno" > 81< / span >   < span class = "keywordtype" > size_t< / span > plaintext_size,< / div >
< div class = "line" > < a name = "l00082" > < / a > < span class = "lineno" > 82< / span >   uint8_t* ciphertext) {< / div >
< div class = "line" > < a name = "l00083" > < / a > < span class = "lineno" > 83< / span >   DCHECK(plaintext);< / div >
< div class = "line" > < a name = "l00084" > < / a > < span class = "lineno" > 84< / span >   DCHECK(ciphertext);< / div >
< div class = "line" > < a name = "l00085" > < / a > < span class = "lineno" > 85< / span >   DCHECK(aes_key_);< / div >
< div class = "line" > < a name = "l00086" > < / a > < span class = "lineno" > 86< / span >   < / div >
< div class = "line" > < a name = "l00087" > < / a > < span class = "lineno" > 87< / span >   < span class = "keywordflow" > for< / span > (< span class = "keywordtype" > size_t< / span > i = 0; i < plaintext_size; ++i) {< / div >
< div class = "line" > < a name = "l00088" > < / a > < span class = "lineno" > 88< / span >   < span class = "keywordflow" > if< / span > (block_offset_ == 0) {< / div >
< div class = "line" > < a name = "l00089" > < / a > < span class = "lineno" > 89< / span >   AES_encrypt(& counter_[0], & encrypted_counter_[0], aes_key_.get());< / div >
< div class = "line" > < a name = "l00090" > < / a > < span class = "lineno" > 90< / span >   < span class = "comment" > // As mentioned in ISO/IEC FDIS 23001-7: CENC spec, of the 16 byte counter< / span > < / div >
< div class = "line" > < a name = "l00091" > < / a > < span class = "lineno" > 91< / span >   < span class = "comment" > // block, bytes 8 to 15 (i.e. the least significant bytes) are used as a< / span > < / div >
< div class = "line" > < a name = "l00092" > < / a > < span class = "lineno" > 92< / span >   < span class = "comment" > // simple 64 bit unsigned integer that is incremented by one for each< / span > < / div >
< div class = "line" > < a name = "l00093" > < / a > < span class = "lineno" > 93< / span >   < span class = "comment" > // subsequent block of sample data processed and is kept in network byte< / span > < / div >
< div class = "line" > < a name = "l00094" > < / a > < span class = "lineno" > 94< / span >   < span class = "comment" > // order.< / span > < / div >
< div class = "line" > < a name = "l00095" > < / a > < span class = "lineno" > 95< / span >   < span class = "keywordflow" > if< / span > (Increment64(& counter_[8]))< / div >
< div class = "line" > < a name = "l00096" > < / a > < span class = "lineno" > 96< / span >   counter_overflow_ = < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00097" > < / a > < span class = "lineno" > 97< / span >   }< / div >
< div class = "line" > < a name = "l00098" > < / a > < span class = "lineno" > 98< / span >   ciphertext[i] = plaintext[i] ^ encrypted_counter_[block_offset_];< / div >
< div class = "line" > < a name = "l00099" > < / a > < span class = "lineno" > 99< / span >   block_offset_ = (block_offset_ + 1) % AES_BLOCK_SIZE;< / div >
< div class = "line" > < a name = "l00100" > < / a > < span class = "lineno" > 100< / span >   }< / div >
< div class = "line" > < a name = "l00101" > < / a > < span class = "lineno" > 101< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00102" > < / a > < span class = "lineno" > 102< / span >   }< / div >
< div class = "line" > < a name = "l00103" > < / a > < span class = "lineno" > 103< / span >   < / div >
< div class = "line" > < a name = "l00104" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d79/classedash__packager_1_1media_1_1AesCtrEncryptor.html#a8310ce3e9ef83a899173bbd1e6ac5583" > 104< / a > < / span >   < span class = "keywordtype" > void< / span > AesCtrEncryptor::UpdateIv() {< / div >
< div class = "line" > < a name = "l00105" > < / a > < span class = "lineno" > 105< / span >   block_offset_ = 0;< / div >
< div class = "line" > < a name = "l00106" > < / a > < span class = "lineno" > 106< / span >   < / div >
< div class = "line" > < a name = "l00107" > < / a > < span class = "lineno" > 107< / span >   < span class = "comment" > // As recommended in ISO/IEC FDIS 23001-7: CENC spec, for 64-bit (8-byte)< / span > < / div >
< div class = "line" > < a name = "l00108" > < / a > < span class = "lineno" > 108< / span >   < span class = "comment" > // IV_Sizes, initialization vectors for subsequent samples can be created by< / span > < / div >
< div class = "line" > < a name = "l00109" > < / a > < span class = "lineno" > 109< / span >   < span class = "comment" > // incrementing the initialization vector of the previous sample.< / span > < / div >
< div class = "line" > < a name = "l00110" > < / a > < span class = "lineno" > 110< / span >   < span class = "comment" > // For 128-bit (16-byte) IV_Sizes, initialization vectors for subsequent< / span > < / div >
< div class = "line" > < a name = "l00111" > < / a > < span class = "lineno" > 111< / span >   < span class = "comment" > // samples should be created by adding the block count of the previous sample< / span > < / div >
< div class = "line" > < a name = "l00112" > < / a > < span class = "lineno" > 112< / span >   < span class = "comment" > // to the initialization vector of the previous sample.< / span > < / div >
< div class = "line" > < a name = "l00113" > < / a > < span class = "lineno" > 113< / span >   < span class = "keywordflow" > if< / span > (iv_.size() == 8) {< / div >
< div class = "line" > < a name = "l00114" > < / a > < span class = "lineno" > 114< / span >   Increment64(& iv_[0]);< / div >
< div class = "line" > < a name = "l00115" > < / a > < span class = "lineno" > 115< / span >   counter_ = iv_;< / div >
< div class = "line" > < a name = "l00116" > < / a > < span class = "lineno" > 116< / span >   counter_.resize(AES_BLOCK_SIZE, 0);< / div >
< div class = "line" > < a name = "l00117" > < / a > < span class = "lineno" > 117< / span >   } < span class = "keywordflow" > else< / span > {< / div >
< div class = "line" > < a name = "l00118" > < / a > < span class = "lineno" > 118< / span >   DCHECK_EQ(16u, iv_.size());< / div >
< div class = "line" > < a name = "l00119" > < / a > < span class = "lineno" > 119< / span >   < span class = "comment" > // Even though the block counter portion of the counter (bytes 8 to 15) is< / span > < / div >
< div class = "line" > < a name = "l00120" > < / a > < span class = "lineno" > 120< / span >   < span class = "comment" > // treated as a 64-bit number, it is recommended that the initialization< / span > < / div >
< div class = "line" > < a name = "l00121" > < / a > < span class = "lineno" > 121< / span >   < span class = "comment" > // vector is treated as a 128-bit number when calculating the next< / span > < / div >
< div class = "line" > < a name = "l00122" > < / a > < span class = "lineno" > 122< / span >   < span class = "comment" > // initialization vector from the previous one. The block counter portion< / span > < / div >
< div class = "line" > < a name = "l00123" > < / a > < span class = "lineno" > 123< / span >   < span class = "comment" > // is already incremented by number of blocks, the other 64 bits of the< / span > < / div >
< div class = "line" > < a name = "l00124" > < / a > < span class = "lineno" > 124< / span >   < span class = "comment" > // counter (bytes 0 to 7) is incremented here if the block counter portion< / span > < / div >
< div class = "line" > < a name = "l00125" > < / a > < span class = "lineno" > 125< / span >   < span class = "comment" > // has overflowed.< / span > < / div >
< div class = "line" > < a name = "l00126" > < / a > < span class = "lineno" > 126< / span >   < span class = "keywordflow" > if< / span > (counter_overflow_)< / div >
< div class = "line" > < a name = "l00127" > < / a > < span class = "lineno" > 127< / span >   Increment64(& counter_[0]);< / div >
< div class = "line" > < a name = "l00128" > < / a > < span class = "lineno" > 128< / span >   iv_ = counter_;< / div >
< div class = "line" > < a name = "l00129" > < / a > < span class = "lineno" > 129< / span >   }< / div >
< div class = "line" > < a name = "l00130" > < / a > < span class = "lineno" > 130< / span >   counter_overflow_ = < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00131" > < / a > < span class = "lineno" > 131< / span >   }< / div >
< div class = "line" > < a name = "l00132" > < / a > < span class = "lineno" > 132< / span >   < / div >
< div class = "line" > < a name = "l00133" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d79/classedash__packager_1_1media_1_1AesCtrEncryptor.html#a9c68238a73c834fd795d3e4d5e8cfd10" > 133< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCtrEncryptor::SetIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00134" > < / a > < span class = "lineno" > 134< / span >   < span class = "keywordflow" > if< / span > (!IsIvSizeValid(iv.size())) {< / div >
< div class = "line" > < a name = "l00135" > < / a > < span class = "lineno" > 135< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00136" > < / a > < span class = "lineno" > 136< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00137" > < / a > < span class = "lineno" > 137< / span >   }< / div >
< div class = "line" > < a name = "l00138" > < / a > < span class = "lineno" > 138< / span >   < / div >
< div class = "line" > < a name = "l00139" > < / a > < span class = "lineno" > 139< / span >   block_offset_ = 0;< / div >
< div class = "line" > < a name = "l00140" > < / a > < span class = "lineno" > 140< / span >   counter_ = iv_ = iv;< / div >
< div class = "line" > < a name = "l00141" > < / a > < span class = "lineno" > 141< / span >   counter_.resize(AES_BLOCK_SIZE, 0);< / div >
< div class = "line" > < a name = "l00142" > < / a > < span class = "lineno" > 142< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00143" > < / a > < span class = "lineno" > 143< / span >   }< / div >
< div class = "line" > < a name = "l00144" > < / a > < span class = "lineno" > 144< / span >   < / div >
< div class = "line" > < a name = "l00145" > < / a > < span class = "lineno" > 145< / span >   AesCbcPkcs5Encryptor::AesCbcPkcs5Encryptor() {}< / div >
< div class = "line" > < a name = "l00146" > < / a > < span class = "lineno" > 146< / span >   AesCbcPkcs5Encryptor::~AesCbcPkcs5Encryptor() {}< / div >
< div class = "line" > < a name = "l00147" > < / a > < span class = "lineno" > 147< / span >   < / div >
< div class = "line" > < a name = "l00148" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/dc4/classedash__packager_1_1media_1_1AesCbcPkcs5Encryptor.html#a6a960fa0d83359156cfd6e10167a69e2" > 148< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcPkcs5Encryptor::InitializeWithIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & key,< / div >
< div class = "line" > < a name = "l00149" > < / a > < span class = "lineno" > 149< / span >   < span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00150" > < / a > < span class = "lineno" > 150< / span >   < span class = "keywordflow" > if< / span > (!IsKeySizeValidForAes(key.size())) {< / div >
< div class = "line" > < a name = "l00151" > < / a > < span class = "lineno" > 151< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid AES key size: " < / span > < < key.size();< / div >
< div class = "line" > < a name = "l00152" > < / a > < span class = "lineno" > 152< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00153" > < / a > < span class = "lineno" > 153< / span >   }< / div >
< div class = "line" > < a name = "l00154" > < / a > < span class = "lineno" > 154< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00155" > < / a > < span class = "lineno" > 155< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00156" > < / a > < span class = "lineno" > 156< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00157" > < / a > < span class = "lineno" > 157< / span >   }< / div >
< div class = "line" > < a name = "l00158" > < / a > < span class = "lineno" > 158< / span >   < / div >
< div class = "line" > < a name = "l00159" > < / a > < span class = "lineno" > 159< / span >   encrypt_key_.reset(< span class = "keyword" > new< / span > AES_KEY());< / div >
< div class = "line" > < a name = "l00160" > < / a > < span class = "lineno" > 160< / span >   CHECK_EQ(AES_set_encrypt_key(& key[0], key.size() * 8, encrypt_key_.get()), 0);< / div >
< div class = "line" > < a name = "l00161" > < / a > < span class = "lineno" > 161< / span >   < / div >
< div class = "line" > < a name = "l00162" > < / a > < span class = "lineno" > 162< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00163" > < / a > < span class = "lineno" > 163< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00164" > < / a > < span class = "lineno" > 164< / span >   }< / div >
< div class = "line" > < a name = "l00165" > < / a > < span class = "lineno" > 165< / span >   < / div >
< div class = "line" > < a name = "l00166" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/dc4/classedash__packager_1_1media_1_1AesCbcPkcs5Encryptor.html#aa9e31be1aef797b9c06e5f3beb524dc8" > 166< / a > < / span >   < span class = "keywordtype" > void< / span > AesCbcPkcs5Encryptor::Encrypt(< span class = "keyword" > const< / span > std::string& plaintext,< / div >
< div class = "line" > < a name = "l00167" > < / a > < span class = "lineno" > 167< / span >   std::string* ciphertext) {< / div >
< div class = "line" > < a name = "l00168" > < / a > < span class = "lineno" > 168< / span >   DCHECK(ciphertext);< / div >
< div class = "line" > < a name = "l00169" > < / a > < span class = "lineno" > 169< / span >   DCHECK(encrypt_key_);< / div >
< div class = "line" > < a name = "l00170" > < / a > < span class = "lineno" > 170< / span >   < / div >
< div class = "line" > < a name = "l00171" > < / a > < span class = "lineno" > 171< / span >   < span class = "comment" > // Pad the input with PKCS5 padding.< / span > < / div >
< div class = "line" > < a name = "l00172" > < / a > < span class = "lineno" > 172< / span >   < span class = "keyword" > const< / span > < span class = "keywordtype" > size_t< / span > num_padding_bytes =< / div >
< div class = "line" > < a name = "l00173" > < / a > < span class = "lineno" > 173< / span >   AES_BLOCK_SIZE - (plaintext.size() % AES_BLOCK_SIZE);< / div >
< div class = "line" > < a name = "l00174" > < / a > < span class = "lineno" > 174< / span >   std::string padded_text = plaintext;< / div >
< div class = "line" > < a name = "l00175" > < / a > < span class = "lineno" > 175< / span >   padded_text.append(num_padding_bytes, static_cast< char> (num_padding_bytes));< / div >
< div class = "line" > < a name = "l00176" > < / a > < span class = "lineno" > 176< / span >   < / div >
< div class = "line" > < a name = "l00177" > < / a > < span class = "lineno" > 177< / span >   ciphertext-> resize(padded_text.size());< / div >
< div class = "line" > < a name = "l00178" > < / a > < span class = "lineno" > 178< / span >   std::vector< uint8_t> iv(iv_);< / div >
< div class = "line" > < a name = "l00179" > < / a > < span class = "lineno" > 179< / span >   AES_cbc_encrypt(reinterpret_cast< const uint8_t*> (padded_text.data()),< / div >
< div class = "line" > < a name = "l00180" > < / a > < span class = "lineno" > 180< / span >   reinterpret_cast< uint8_t*> (string_as_array(ciphertext)),< / div >
< div class = "line" > < a name = "l00181" > < / a > < span class = "lineno" > 181< / span >   padded_text.size(),< / div >
< div class = "line" > < a name = "l00182" > < / a > < span class = "lineno" > 182< / span >   encrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00183" > < / a > < span class = "lineno" > 183< / span >   & iv[0],< / div >
< div class = "line" > < a name = "l00184" > < / a > < span class = "lineno" > 184< / span >   AES_ENCRYPT);< / div >
< div class = "line" > < a name = "l00185" > < / a > < span class = "lineno" > 185< / span >   }< / div >
< div class = "line" > < a name = "l00186" > < / a > < span class = "lineno" > 186< / span >   < / div >
< div class = "line" > < a name = "l00187" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/dc4/classedash__packager_1_1media_1_1AesCbcPkcs5Encryptor.html#aca87525a4f8b27efc3e6eefcbe26f55f" > 187< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcPkcs5Encryptor::SetIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00188" > < / a > < span class = "lineno" > 188< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00189" > < / a > < span class = "lineno" > 189< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00190" > < / a > < span class = "lineno" > 190< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00191" > < / a > < span class = "lineno" > 191< / span >   }< / div >
< div class = "line" > < a name = "l00192" > < / a > < span class = "lineno" > 192< / span >   < / div >
< div class = "line" > < a name = "l00193" > < / a > < span class = "lineno" > 193< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00194" > < / a > < span class = "lineno" > 194< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00195" > < / a > < span class = "lineno" > 195< / span >   }< / div >
< div class = "line" > < a name = "l00196" > < / a > < span class = "lineno" > 196< / span >   < / div >
< div class = "line" > < a name = "l00197" > < / a > < span class = "lineno" > 197< / span >   AesCbcPkcs5Decryptor::AesCbcPkcs5Decryptor() {}< / div >
< div class = "line" > < a name = "l00198" > < / a > < span class = "lineno" > 198< / span >   AesCbcPkcs5Decryptor::~AesCbcPkcs5Decryptor() {}< / div >
< div class = "line" > < a name = "l00199" > < / a > < span class = "lineno" > 199< / span >   < / div >
< div class = "line" > < a name = "l00200" > < / a > < span class = "lineno" > < a class = "line" href = "../../db/dfe/classedash__packager_1_1media_1_1AesCbcPkcs5Decryptor.html#aaa17492b546264e815971e9f6925a460" > 200< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcPkcs5Decryptor::InitializeWithIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & key,< / div >
< div class = "line" > < a name = "l00201" > < / a > < span class = "lineno" > 201< / span >   < span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00202" > < / a > < span class = "lineno" > 202< / span >   < span class = "keywordflow" > if< / span > (!IsKeySizeValidForAes(key.size())) {< / div >
< div class = "line" > < a name = "l00203" > < / a > < span class = "lineno" > 203< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid AES key size: " < / span > < < key.size();< / div >
< div class = "line" > < a name = "l00204" > < / a > < span class = "lineno" > 204< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00205" > < / a > < span class = "lineno" > 205< / span >   }< / div >
< div class = "line" > < a name = "l00206" > < / a > < span class = "lineno" > 206< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00207" > < / a > < span class = "lineno" > 207< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00208" > < / a > < span class = "lineno" > 208< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00209" > < / a > < span class = "lineno" > 209< / span >   }< / div >
< div class = "line" > < a name = "l00210" > < / a > < span class = "lineno" > 210< / span >   < / div >
< div class = "line" > < a name = "l00211" > < / a > < span class = "lineno" > 211< / span >   decrypt_key_.reset(< span class = "keyword" > new< / span > AES_KEY());< / div >
< div class = "line" > < a name = "l00212" > < / a > < span class = "lineno" > 212< / span >   CHECK_EQ(AES_set_decrypt_key(& key[0], key.size() * 8, decrypt_key_.get()), 0);< / div >
< div class = "line" > < a name = "l00213" > < / a > < span class = "lineno" > 213< / span >   < / div >
< div class = "line" > < a name = "l00214" > < / a > < span class = "lineno" > 214< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00215" > < / a > < span class = "lineno" > 215< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00216" > < / a > < span class = "lineno" > 216< / span >   }< / div >
< div class = "line" > < a name = "l00217" > < / a > < span class = "lineno" > 217< / span >   < / div >
< div class = "line" > < a name = "l00218" > < / a > < span class = "lineno" > < a class = "line" href = "../../db/dfe/classedash__packager_1_1media_1_1AesCbcPkcs5Decryptor.html#a99992a6413029b81074735a74ce392e3" > 218< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcPkcs5Decryptor::Decrypt(< span class = "keyword" > const< / span > std::string& ciphertext,< / div >
< div class = "line" > < a name = "l00219" > < / a > < span class = "lineno" > 219< / span >   std::string* plaintext) {< / div >
< div class = "line" > < a name = "l00220" > < / a > < span class = "lineno" > 220< / span >   < span class = "keywordflow" > if< / span > ((ciphertext.size() % AES_BLOCK_SIZE) != 0) {< / div >
< div class = "line" > < a name = "l00221" > < / a > < span class = "lineno" > 221< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Expecting cipher text size to be multiple of " < / span > < / div >
< div class = "line" > < a name = "l00222" > < / a > < span class = "lineno" > 222< / span >   < < AES_BLOCK_SIZE < < < span class = "stringliteral" > " , got " < / span > < < ciphertext.size();< / div >
< div class = "line" > < a name = "l00223" > < / a > < span class = "lineno" > 223< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00224" > < / a > < span class = "lineno" > 224< / span >   }< / div >
< div class = "line" > < a name = "l00225" > < / a > < span class = "lineno" > 225< / span >   < / div >
< div class = "line" > < a name = "l00226" > < / a > < span class = "lineno" > 226< / span >   DCHECK(plaintext);< / div >
< div class = "line" > < a name = "l00227" > < / a > < span class = "lineno" > 227< / span >   DCHECK(decrypt_key_);< / div >
< div class = "line" > < a name = "l00228" > < / a > < span class = "lineno" > 228< / span >   < / div >
< div class = "line" > < a name = "l00229" > < / a > < span class = "lineno" > 229< / span >   plaintext-> resize(ciphertext.size());< / div >
< div class = "line" > < a name = "l00230" > < / a > < span class = "lineno" > 230< / span >   AES_cbc_encrypt(reinterpret_cast< const uint8_t*> (ciphertext.data()),< / div >
< div class = "line" > < a name = "l00231" > < / a > < span class = "lineno" > 231< / span >   reinterpret_cast< uint8_t*> (string_as_array(plaintext)),< / div >
< div class = "line" > < a name = "l00232" > < / a > < span class = "lineno" > 232< / span >   ciphertext.size(),< / div >
< div class = "line" > < a name = "l00233" > < / a > < span class = "lineno" > 233< / span >   decrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00234" > < / a > < span class = "lineno" > 234< / span >   & iv_[0],< / div >
< div class = "line" > < a name = "l00235" > < / a > < span class = "lineno" > 235< / span >   AES_DECRYPT);< / div >
< div class = "line" > < a name = "l00236" > < / a > < span class = "lineno" > 236< / span >   < / div >
< div class = "line" > < a name = "l00237" > < / a > < span class = "lineno" > 237< / span >   < span class = "comment" > // Strip off PKCS5 padding bytes.< / span > < / div >
< div class = "line" > < a name = "l00238" > < / a > < span class = "lineno" > 238< / span >   < span class = "keyword" > const< / span > uint8_t num_padding_bytes = (*plaintext)[plaintext-> size() - 1];< / div >
< div class = "line" > < a name = "l00239" > < / a > < span class = "lineno" > 239< / span >   < span class = "keywordflow" > if< / span > (num_padding_bytes > AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00240" > < / a > < span class = "lineno" > 240< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Padding length is too large : " < / span > < / div >
< div class = "line" > < a name = "l00241" > < / a > < span class = "lineno" > 241< / span >   < < < span class = "keyword" > static_cast< < / span > < span class = "keywordtype" > int< / span > < span class = "keyword" > > < / span > (num_padding_bytes);< / div >
< div class = "line" > < a name = "l00242" > < / a > < span class = "lineno" > 242< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00243" > < / a > < span class = "lineno" > 243< / span >   }< / div >
< div class = "line" > < a name = "l00244" > < / a > < span class = "lineno" > 244< / span >   plaintext-> resize(plaintext-> size() - num_padding_bytes);< / div >
< div class = "line" > < a name = "l00245" > < / a > < span class = "lineno" > 245< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00246" > < / a > < span class = "lineno" > 246< / span >   }< / div >
< div class = "line" > < a name = "l00247" > < / a > < span class = "lineno" > 247< / span >   < / div >
< div class = "line" > < a name = "l00248" > < / a > < span class = "lineno" > < a class = "line" href = "../../db/dfe/classedash__packager_1_1media_1_1AesCbcPkcs5Decryptor.html#a0944b9d110e89fa9d63b03060059954e" > 248< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcPkcs5Decryptor::SetIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00249" > < / a > < span class = "lineno" > 249< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00250" > < / a > < span class = "lineno" > 250< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00251" > < / a > < span class = "lineno" > 251< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00252" > < / a > < span class = "lineno" > 252< / span >   }< / div >
< div class = "line" > < a name = "l00253" > < / a > < span class = "lineno" > 253< / span >   < / div >
< div class = "line" > < a name = "l00254" > < / a > < span class = "lineno" > 254< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00255" > < / a > < span class = "lineno" > 255< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00256" > < / a > < span class = "lineno" > 256< / span >   }< / div >
< div class = "line" > < a name = "l00257" > < / a > < span class = "lineno" > 257< / span >   < / div >
< div class = "line" > < a name = "l00258" > < / a > < span class = "lineno" > 258< / span >   AesCbcCtsEncryptor::AesCbcCtsEncryptor() {}< / div >
< div class = "line" > < a name = "l00259" > < / a > < span class = "lineno" > 259< / span >   AesCbcCtsEncryptor::~AesCbcCtsEncryptor() {}< / div >
< div class = "line" > < a name = "l00260" > < / a > < span class = "lineno" > 260< / span >   < / div >
< div class = "line" > < a name = "l00261" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/da2/classedash__packager_1_1media_1_1AesCbcCtsEncryptor.html#a5f48de14959ae35fdd9e2e95ab0274b4" > 261< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcCtsEncryptor::InitializeWithIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & key,< / div >
< div class = "line" > < a name = "l00262" > < / a > < span class = "lineno" > 262< / span >   < span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00263" > < / a > < span class = "lineno" > 263< / span >   < span class = "keywordflow" > if< / span > (!IsKeySizeValidForAes(key.size())) {< / div >
< div class = "line" > < a name = "l00264" > < / a > < span class = "lineno" > 264< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid AES key size: " < / span > < < key.size();< / div >
< div class = "line" > < a name = "l00265" > < / a > < span class = "lineno" > 265< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00266" > < / a > < span class = "lineno" > 266< / span >   }< / div >
< div class = "line" > < a name = "l00267" > < / a > < span class = "lineno" > 267< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00268" > < / a > < span class = "lineno" > 268< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00269" > < / a > < span class = "lineno" > 269< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00270" > < / a > < span class = "lineno" > 270< / span >   }< / div >
< div class = "line" > < a name = "l00271" > < / a > < span class = "lineno" > 271< / span >   < / div >
< div class = "line" > < a name = "l00272" > < / a > < span class = "lineno" > 272< / span >   encrypt_key_.reset(< span class = "keyword" > new< / span > AES_KEY());< / div >
< div class = "line" > < a name = "l00273" > < / a > < span class = "lineno" > 273< / span >   CHECK_EQ(AES_set_encrypt_key(& key[0], key.size() * 8, encrypt_key_.get()), 0);< / div >
< div class = "line" > < a name = "l00274" > < / a > < span class = "lineno" > 274< / span >   < / div >
< div class = "line" > < a name = "l00275" > < / a > < span class = "lineno" > 275< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00276" > < / a > < span class = "lineno" > 276< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00277" > < / a > < span class = "lineno" > 277< / span >   }< / div >
< div class = "line" > < a name = "l00278" > < / a > < span class = "lineno" > 278< / span >   < / div >
< div class = "line" > < a name = "l00279" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/da2/classedash__packager_1_1media_1_1AesCbcCtsEncryptor.html#a8bc803d458d2443cb59d20b6d14c3c30" > 279< / a > < / span >   < span class = "keywordtype" > void< / span > AesCbcCtsEncryptor::Encrypt(< span class = "keyword" > const< / span > uint8_t* plaintext,< / div >
< div class = "line" > < a name = "l00280" > < / a > < span class = "lineno" > 280< / span >   < span class = "keywordtype" > size_t< / span > size,< / div >
< div class = "line" > < a name = "l00281" > < / a > < span class = "lineno" > 281< / span >   uint8_t* ciphertext) {< / div >
< div class = "line" > < a name = "l00282" > < / a > < span class = "lineno" > 282< / span >   DCHECK(plaintext);< / div >
< div class = "line" > < a name = "l00283" > < / a > < span class = "lineno" > 283< / span >   DCHECK(ciphertext);< / div >
< div class = "line" > < a name = "l00284" > < / a > < span class = "lineno" > 284< / span >   < / div >
< div class = "line" > < a name = "l00285" > < / a > < span class = "lineno" > 285< / span >   < span class = "keywordflow" > if< / span > (size < AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00286" > < / a > < span class = "lineno" > 286< / span >   < span class = "comment" > // Don' t have a full block, leave unencrypted.< / span > < / div >
< div class = "line" > < a name = "l00287" > < / a > < span class = "lineno" > 287< / span >   memcpy(ciphertext, plaintext, size);< / div >
< div class = "line" > < a name = "l00288" > < / a > < span class = "lineno" > 288< / span >   < span class = "keywordflow" > return< / span > ;< / div >
< div class = "line" > < a name = "l00289" > < / a > < span class = "lineno" > 289< / span >   }< / div >
< div class = "line" > < a name = "l00290" > < / a > < span class = "lineno" > 290< / span >   < / div >
< div class = "line" > < a name = "l00291" > < / a > < span class = "lineno" > 291< / span >   std::vector< uint8_t> iv(iv_);< / div >
< div class = "line" > < a name = "l00292" > < / a > < span class = "lineno" > 292< / span >   < span class = "keywordtype" > size_t< / span > residual_block_size = size % AES_BLOCK_SIZE;< / div >
< div class = "line" > < a name = "l00293" > < / a > < span class = "lineno" > 293< / span >   < span class = "keywordtype" > size_t< / span > cbc_size = size - residual_block_size;< / div >
< div class = "line" > < a name = "l00294" > < / a > < span class = "lineno" > 294< / span >   < / div >
< div class = "line" > < a name = "l00295" > < / a > < span class = "lineno" > 295< / span >   < span class = "comment" > // Encrypt everything but the residual block using CBC.< / span > < / div >
< div class = "line" > < a name = "l00296" > < / a > < span class = "lineno" > 296< / span >   AES_cbc_encrypt(plaintext,< / div >
< div class = "line" > < a name = "l00297" > < / a > < span class = "lineno" > 297< / span >   ciphertext,< / div >
< div class = "line" > < a name = "l00298" > < / a > < span class = "lineno" > 298< / span >   cbc_size,< / div >
< div class = "line" > < a name = "l00299" > < / a > < span class = "lineno" > 299< / span >   encrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00300" > < / a > < span class = "lineno" > 300< / span >   & iv[0],< / div >
< div class = "line" > < a name = "l00301" > < / a > < span class = "lineno" > 301< / span >   AES_ENCRYPT);< / div >
< div class = "line" > < a name = "l00302" > < / a > < span class = "lineno" > 302< / span >   < span class = "keywordflow" > if< / span > (residual_block_size == 0) {< / div >
< div class = "line" > < a name = "l00303" > < / a > < span class = "lineno" > 303< / span >   < span class = "comment" > // No residual block. No need to do ciphertext stealing.< / span > < / div >
< div class = "line" > < a name = "l00304" > < / a > < span class = "lineno" > 304< / span >   < span class = "keywordflow" > return< / span > ;< / div >
< div class = "line" > < a name = "l00305" > < / a > < span class = "lineno" > 305< / span >   }< / div >
< div class = "line" > < a name = "l00306" > < / a > < span class = "lineno" > 306< / span >   < / div >
< div class = "line" > < a name = "l00307" > < / a > < span class = "lineno" > 307< / span >   < span class = "comment" > // Zero-pad the residual block and encrypt using CBC.< / span > < / div >
< div class = "line" > < a name = "l00308" > < / a > < span class = "lineno" > 308< / span >   std::vector< uint8_t> residual_block(plaintext + size - residual_block_size,< / div >
< div class = "line" > < a name = "l00309" > < / a > < span class = "lineno" > 309< / span >   plaintext + size);< / div >
< div class = "line" > < a name = "l00310" > < / a > < span class = "lineno" > 310< / span >   residual_block.resize(AES_BLOCK_SIZE, 0);< / div >
< div class = "line" > < a name = "l00311" > < / a > < span class = "lineno" > 311< / span >   AES_cbc_encrypt(& residual_block[0],< / div >
< div class = "line" > < a name = "l00312" > < / a > < span class = "lineno" > 312< / span >   & residual_block[0],< / div >
< div class = "line" > < a name = "l00313" > < / a > < span class = "lineno" > 313< / span >   AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00314" > < / a > < span class = "lineno" > 314< / span >   encrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00315" > < / a > < span class = "lineno" > 315< / span >   & iv[0],< / div >
< div class = "line" > < a name = "l00316" > < / a > < span class = "lineno" > 316< / span >   AES_ENCRYPT);< / div >
< div class = "line" > < a name = "l00317" > < / a > < span class = "lineno" > 317< / span >   < / div >
< div class = "line" > < a name = "l00318" > < / a > < span class = "lineno" > 318< / span >   < span class = "comment" > // Replace the last full block with the zero-padded, encrypted residual block,< / span > < / div >
< div class = "line" > < a name = "l00319" > < / a > < span class = "lineno" > 319< / span >   < span class = "comment" > // and replace the residual block with the equivalent portion of the last full< / span > < / div >
< div class = "line" > < a name = "l00320" > < / a > < span class = "lineno" > 320< / span >   < span class = "comment" > // encrypted block. It may appear that some encrypted bits of the last full< / span > < / div >
< div class = "line" > < a name = "l00321" > < / a > < span class = "lineno" > 321< / span >   < span class = "comment" > // block are lost, but they are not, as they were used as the IV when< / span > < / div >
< div class = "line" > < a name = "l00322" > < / a > < span class = "lineno" > 322< / span >   < span class = "comment" > // encrypting the zero-padded residual block.< / span > < / div >
< div class = "line" > < a name = "l00323" > < / a > < span class = "lineno" > 323< / span >   uint8_t* residual_ciphertext_block = ciphertext + size - residual_block_size;< / div >
< div class = "line" > < a name = "l00324" > < / a > < span class = "lineno" > 324< / span >   memcpy(residual_ciphertext_block,< / div >
< div class = "line" > < a name = "l00325" > < / a > < span class = "lineno" > 325< / span >   residual_ciphertext_block - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00326" > < / a > < span class = "lineno" > 326< / span >   residual_block_size);< / div >
< div class = "line" > < a name = "l00327" > < / a > < span class = "lineno" > 327< / span >   memcpy(residual_ciphertext_block - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00328" > < / a > < span class = "lineno" > 328< / span >   residual_block.data(),< / div >
< div class = "line" > < a name = "l00329" > < / a > < span class = "lineno" > 329< / span >   AES_BLOCK_SIZE);< / div >
< div class = "line" > < a name = "l00330" > < / a > < span class = "lineno" > 330< / span >   }< / div >
< div class = "line" > < a name = "l00331" > < / a > < span class = "lineno" > 331< / span >   < / div >
< div class = "line" > < a name = "l00332" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/da2/classedash__packager_1_1media_1_1AesCbcCtsEncryptor.html#acd3e07715507f0edebf92dc14535aa70" > 332< / a > < / span >   < span class = "keywordtype" > void< / span > AesCbcCtsEncryptor::Encrypt(< span class = "keyword" > const< / span > std::vector< uint8_t> & plaintext,< / div >
< div class = "line" > < a name = "l00333" > < / a > < span class = "lineno" > 333< / span >   std::vector< uint8_t> * ciphertext) {< / div >
< div class = "line" > < a name = "l00334" > < / a > < span class = "lineno" > 334< / span >   DCHECK(ciphertext);< / div >
< div class = "line" > < a name = "l00335" > < / a > < span class = "lineno" > 335< / span >   < / div >
< div class = "line" > < a name = "l00336" > < / a > < span class = "lineno" > 336< / span >   ciphertext-> resize(plaintext.size(), 0);< / div >
< div class = "line" > < a name = "l00337" > < / a > < span class = "lineno" > 337< / span >   < span class = "keywordflow" > if< / span > (plaintext.empty())< / div >
< div class = "line" > < a name = "l00338" > < / a > < span class = "lineno" > 338< / span >   < span class = "keywordflow" > return< / span > ;< / div >
< div class = "line" > < a name = "l00339" > < / a > < span class = "lineno" > 339< / span >   < / div >
< div class = "line" > < a name = "l00340" > < / a > < span class = "lineno" > 340< / span >   Encrypt(plaintext.data(), plaintext.size(), & (*ciphertext)[0]);< / div >
< div class = "line" > < a name = "l00341" > < / a > < span class = "lineno" > 341< / span >   }< / div >
< div class = "line" > < a name = "l00342" > < / a > < span class = "lineno" > 342< / span >   < / div >
< div class = "line" > < a name = "l00343" > < / a > < span class = "lineno" > < a class = "line" href = "../../d6/da2/classedash__packager_1_1media_1_1AesCbcCtsEncryptor.html#a797a78aad46c2b148398c6d15f2b39e3" > 343< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcCtsEncryptor::SetIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00344" > < / a > < span class = "lineno" > 344< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00345" > < / a > < span class = "lineno" > 345< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00346" > < / a > < span class = "lineno" > 346< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00347" > < / a > < span class = "lineno" > 347< / span >   }< / div >
< div class = "line" > < a name = "l00348" > < / a > < span class = "lineno" > 348< / span >   < / div >
< div class = "line" > < a name = "l00349" > < / a > < span class = "lineno" > 349< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00350" > < / a > < span class = "lineno" > 350< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00351" > < / a > < span class = "lineno" > 351< / span >   }< / div >
< div class = "line" > < a name = "l00352" > < / a > < span class = "lineno" > 352< / span >   < / div >
< div class = "line" > < a name = "l00353" > < / a > < span class = "lineno" > 353< / span >   AesCbcCtsDecryptor::AesCbcCtsDecryptor() {}< / div >
< div class = "line" > < a name = "l00354" > < / a > < span class = "lineno" > 354< / span >   AesCbcCtsDecryptor::~AesCbcCtsDecryptor() {}< / div >
< div class = "line" > < a name = "l00355" > < / a > < span class = "lineno" > 355< / span >   < / div >
< div class = "line" > < a name = "l00356" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d96/classedash__packager_1_1media_1_1AesCbcCtsDecryptor.html#a4ae122dc7410cccec81eabbffa7601da" > 356< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcCtsDecryptor::InitializeWithIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & key,< / div >
< div class = "line" > < a name = "l00357" > < / a > < span class = "lineno" > 357< / span >   < span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00358" > < / a > < span class = "lineno" > 358< / span >   < span class = "keywordflow" > if< / span > (!IsKeySizeValidForAes(key.size())) {< / div >
< div class = "line" > < a name = "l00359" > < / a > < span class = "lineno" > 359< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid AES key size: " < / span > < < key.size();< / div >
< div class = "line" > < a name = "l00360" > < / a > < span class = "lineno" > 360< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00361" > < / a > < span class = "lineno" > 361< / span >   }< / div >
< div class = "line" > < a name = "l00362" > < / a > < span class = "lineno" > 362< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00363" > < / a > < span class = "lineno" > 363< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00364" > < / a > < span class = "lineno" > 364< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00365" > < / a > < span class = "lineno" > 365< / span >   }< / div >
< div class = "line" > < a name = "l00366" > < / a > < span class = "lineno" > 366< / span >   < / div >
< div class = "line" > < a name = "l00367" > < / a > < span class = "lineno" > 367< / span >   decrypt_key_.reset(< span class = "keyword" > new< / span > AES_KEY());< / div >
< div class = "line" > < a name = "l00368" > < / a > < span class = "lineno" > 368< / span >   CHECK_EQ(AES_set_decrypt_key(& key[0], key.size() * 8, decrypt_key_.get()), 0);< / div >
< div class = "line" > < a name = "l00369" > < / a > < span class = "lineno" > 369< / span >   < / div >
< div class = "line" > < a name = "l00370" > < / a > < span class = "lineno" > 370< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00371" > < / a > < span class = "lineno" > 371< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00372" > < / a > < span class = "lineno" > 372< / span >   }< / div >
< div class = "line" > < a name = "l00373" > < / a > < span class = "lineno" > 373< / span >   < / div >
< div class = "line" > < a name = "l00374" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d96/classedash__packager_1_1media_1_1AesCbcCtsDecryptor.html#ab4401816a4dbae48500ce4e8f011c511" > 374< / a > < / span >   < span class = "keywordtype" > void< / span > AesCbcCtsDecryptor::Decrypt(< span class = "keyword" > const< / span > uint8_t* ciphertext,< / div >
< div class = "line" > < a name = "l00375" > < / a > < span class = "lineno" > 375< / span >   < span class = "keywordtype" > size_t< / span > size,< / div >
< div class = "line" > < a name = "l00376" > < / a > < span class = "lineno" > 376< / span >   uint8_t* plaintext) {< / div >
< div class = "line" > < a name = "l00377" > < / a > < span class = "lineno" > 377< / span >   DCHECK(ciphertext);< / div >
< div class = "line" > < a name = "l00378" > < / a > < span class = "lineno" > 378< / span >   DCHECK(plaintext);< / div >
< div class = "line" > < a name = "l00379" > < / a > < span class = "lineno" > 379< / span >   < / div >
< div class = "line" > < a name = "l00380" > < / a > < span class = "lineno" > 380< / span >   < span class = "keywordflow" > if< / span > (size < AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00381" > < / a > < span class = "lineno" > 381< / span >   < span class = "comment" > // Don' t have a full block, leave unencrypted.< / span > < / div >
< div class = "line" > < a name = "l00382" > < / a > < span class = "lineno" > 382< / span >   memcpy(plaintext, ciphertext, size);< / div >
< div class = "line" > < a name = "l00383" > < / a > < span class = "lineno" > 383< / span >   < span class = "keywordflow" > return< / span > ;< / div >
< div class = "line" > < a name = "l00384" > < / a > < span class = "lineno" > 384< / span >   }< / div >
< div class = "line" > < a name = "l00385" > < / a > < span class = "lineno" > 385< / span >   < / div >
< div class = "line" > < a name = "l00386" > < / a > < span class = "lineno" > 386< / span >   std::vector< uint8_t> iv(iv_);< / div >
< div class = "line" > < a name = "l00387" > < / a > < span class = "lineno" > 387< / span >   < span class = "keywordtype" > size_t< / span > residual_block_size = size % AES_BLOCK_SIZE;< / div >
< div class = "line" > < a name = "l00388" > < / a > < span class = "lineno" > 388< / span >   < / div >
< div class = "line" > < a name = "l00389" > < / a > < span class = "lineno" > 389< / span >   < span class = "keywordflow" > if< / span > (residual_block_size == 0) {< / div >
< div class = "line" > < a name = "l00390" > < / a > < span class = "lineno" > 390< / span >   < span class = "comment" > // No residual block. No need to do ciphertext stealing.< / span > < / div >
< div class = "line" > < a name = "l00391" > < / a > < span class = "lineno" > 391< / span >   AES_cbc_encrypt(ciphertext,< / div >
< div class = "line" > < a name = "l00392" > < / a > < span class = "lineno" > 392< / span >   plaintext,< / div >
< div class = "line" > < a name = "l00393" > < / a > < span class = "lineno" > 393< / span >   size,< / div >
< div class = "line" > < a name = "l00394" > < / a > < span class = "lineno" > 394< / span >   decrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00395" > < / a > < span class = "lineno" > 395< / span >   & iv[0],< / div >
< div class = "line" > < a name = "l00396" > < / a > < span class = "lineno" > 396< / span >   AES_DECRYPT);< / div >
< div class = "line" > < a name = "l00397" > < / a > < span class = "lineno" > 397< / span >   < span class = "keywordflow" > return< / span > ;< / div >
< div class = "line" > < a name = "l00398" > < / a > < span class = "lineno" > 398< / span >   }< / div >
< div class = "line" > < a name = "l00399" > < / a > < span class = "lineno" > 399< / span >   < / div >
< div class = "line" > < a name = "l00400" > < / a > < span class = "lineno" > 400< / span >   < span class = "comment" > // AES-CBC decrypt everything up to the next-to-last full block.< / span > < / div >
< div class = "line" > < a name = "l00401" > < / a > < span class = "lineno" > 401< / span >   < span class = "keywordtype" > size_t< / span > cbc_size = size - residual_block_size;< / div >
< div class = "line" > < a name = "l00402" > < / a > < span class = "lineno" > 402< / span >   < span class = "keywordflow" > if< / span > (cbc_size > AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00403" > < / a > < span class = "lineno" > 403< / span >   AES_cbc_encrypt(ciphertext,< / div >
< div class = "line" > < a name = "l00404" > < / a > < span class = "lineno" > 404< / span >   plaintext,< / div >
< div class = "line" > < a name = "l00405" > < / a > < span class = "lineno" > 405< / span >   cbc_size - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00406" > < / a > < span class = "lineno" > 406< / span >   decrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00407" > < / a > < span class = "lineno" > 407< / span >   & iv[0],< / div >
< div class = "line" > < a name = "l00408" > < / a > < span class = "lineno" > 408< / span >   AES_DECRYPT);< / div >
< div class = "line" > < a name = "l00409" > < / a > < span class = "lineno" > 409< / span >   }< / div >
< div class = "line" > < a name = "l00410" > < / a > < span class = "lineno" > 410< / span >   < / div >
< div class = "line" > < a name = "l00411" > < / a > < span class = "lineno" > 411< / span >   < span class = "comment" > // Determine what the last IV should be so that we can " skip ahead" in the< / span > < / div >
< div class = "line" > < a name = "l00412" > < / a > < span class = "lineno" > 412< / span >   < span class = "comment" > // CBC decryption.< / span > < / div >
< div class = "line" > < a name = "l00413" > < / a > < span class = "lineno" > 413< / span >   std::vector< uint8_t> last_iv(ciphertext + size - residual_block_size,< / div >
< div class = "line" > < a name = "l00414" > < / a > < span class = "lineno" > 414< / span >   ciphertext + size);< / div >
< div class = "line" > < a name = "l00415" > < / a > < span class = "lineno" > 415< / span >   last_iv.resize(AES_BLOCK_SIZE, 0);< / div >
< div class = "line" > < a name = "l00416" > < / a > < span class = "lineno" > 416< / span >   < / div >
< div class = "line" > < a name = "l00417" > < / a > < span class = "lineno" > 417< / span >   < span class = "comment" > // Decrypt the next-to-last block using the IV determined above. This decrypts< / span > < / div >
< div class = "line" > < a name = "l00418" > < / a > < span class = "lineno" > 418< / span >   < span class = "comment" > // the residual block bits.< / span > < / div >
< div class = "line" > < a name = "l00419" > < / a > < span class = "lineno" > 419< / span >   AES_cbc_encrypt(ciphertext + size - residual_block_size - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00420" > < / a > < span class = "lineno" > 420< / span >   plaintext + size - residual_block_size - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00421" > < / a > < span class = "lineno" > 421< / span >   AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00422" > < / a > < span class = "lineno" > 422< / span >   decrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00423" > < / a > < span class = "lineno" > 423< / span >   & last_iv[0],< / div >
< div class = "line" > < a name = "l00424" > < / a > < span class = "lineno" > 424< / span >   AES_DECRYPT);< / div >
< div class = "line" > < a name = "l00425" > < / a > < span class = "lineno" > 425< / span >   < / div >
< div class = "line" > < a name = "l00426" > < / a > < span class = "lineno" > 426< / span >   < span class = "comment" > // Swap back the residual block bits and the next-to-last full block.< / span > < / div >
< div class = "line" > < a name = "l00427" > < / a > < span class = "lineno" > 427< / span >   < span class = "keywordflow" > if< / span > (plaintext == ciphertext) {< / div >
< div class = "line" > < a name = "l00428" > < / a > < span class = "lineno" > 428< / span >   uint8_t* ptr1 = plaintext + size - residual_block_size;< / div >
< div class = "line" > < a name = "l00429" > < / a > < span class = "lineno" > 429< / span >   uint8_t* ptr2 = plaintext + size - residual_block_size - AES_BLOCK_SIZE;< / div >
< div class = "line" > < a name = "l00430" > < / a > < span class = "lineno" > 430< / span >   < span class = "keywordflow" > for< / span > (< span class = "keywordtype" > size_t< / span > i = 0; i < residual_block_size; ++i) {< / div >
< div class = "line" > < a name = "l00431" > < / a > < span class = "lineno" > 431< / span >   uint8_t temp = *ptr1;< / div >
< div class = "line" > < a name = "l00432" > < / a > < span class = "lineno" > 432< / span >   *ptr1 = *ptr2;< / div >
< div class = "line" > < a name = "l00433" > < / a > < span class = "lineno" > 433< / span >   *ptr2 = temp;< / div >
< div class = "line" > < a name = "l00434" > < / a > < span class = "lineno" > 434< / span >   ++ptr1;< / div >
< div class = "line" > < a name = "l00435" > < / a > < span class = "lineno" > 435< / span >   ++ptr2;< / div >
< div class = "line" > < a name = "l00436" > < / a > < span class = "lineno" > 436< / span >   }< / div >
< div class = "line" > < a name = "l00437" > < / a > < span class = "lineno" > 437< / span >   } < span class = "keywordflow" > else< / span > {< / div >
< div class = "line" > < a name = "l00438" > < / a > < span class = "lineno" > 438< / span >   uint8_t* residual_plaintext_block = plaintext + size - residual_block_size;< / div >
< div class = "line" > < a name = "l00439" > < / a > < span class = "lineno" > 439< / span >   memcpy(residual_plaintext_block,< / div >
< div class = "line" > < a name = "l00440" > < / a > < span class = "lineno" > 440< / span >   residual_plaintext_block - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00441" > < / a > < span class = "lineno" > 441< / span >   residual_block_size);< / div >
< div class = "line" > < a name = "l00442" > < / a > < span class = "lineno" > 442< / span >   memcpy(residual_plaintext_block - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00443" > < / a > < span class = "lineno" > 443< / span >   ciphertext + size - residual_block_size,< / div >
< div class = "line" > < a name = "l00444" > < / a > < span class = "lineno" > 444< / span >   residual_block_size);< / div >
< div class = "line" > < a name = "l00445" > < / a > < span class = "lineno" > 445< / span >   }< / div >
< div class = "line" > < a name = "l00446" > < / a > < span class = "lineno" > 446< / span >   < / div >
< div class = "line" > < a name = "l00447" > < / a > < span class = "lineno" > 447< / span >   < span class = "comment" > // Decrypt the last full block.< / span > < / div >
< div class = "line" > < a name = "l00448" > < / a > < span class = "lineno" > 448< / span >   AES_cbc_encrypt(plaintext + size - residual_block_size - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00449" > < / a > < span class = "lineno" > 449< / span >   plaintext + size - residual_block_size - AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00450" > < / a > < span class = "lineno" > 450< / span >   AES_BLOCK_SIZE,< / div >
< div class = "line" > < a name = "l00451" > < / a > < span class = "lineno" > 451< / span >   decrypt_key_.get(),< / div >
< div class = "line" > < a name = "l00452" > < / a > < span class = "lineno" > 452< / span >   & iv[0],< / div >
< div class = "line" > < a name = "l00453" > < / a > < span class = "lineno" > 453< / span >   AES_DECRYPT);< / div >
< div class = "line" > < a name = "l00454" > < / a > < span class = "lineno" > 454< / span >   }< / div >
< div class = "line" > < a name = "l00455" > < / a > < span class = "lineno" > 455< / span >   < / div >
< div class = "line" > < a name = "l00456" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d96/classedash__packager_1_1media_1_1AesCbcCtsDecryptor.html#a07ead5ae4cff840782578f123a79c5e8" > 456< / a > < / span >   < span class = "keywordtype" > void< / span > AesCbcCtsDecryptor::Decrypt(< span class = "keyword" > const< / span > std::vector< uint8_t> & ciphertext,< / div >
< div class = "line" > < a name = "l00457" > < / a > < span class = "lineno" > 457< / span >   std::vector< uint8_t> * plaintext) {< / div >
< div class = "line" > < a name = "l00458" > < / a > < span class = "lineno" > 458< / span >   DCHECK(plaintext);< / div >
< div class = "line" > < a name = "l00459" > < / a > < span class = "lineno" > 459< / span >   < / div >
< div class = "line" > < a name = "l00460" > < / a > < span class = "lineno" > 460< / span >   plaintext-> resize(ciphertext.size(), 0);< / div >
< div class = "line" > < a name = "l00461" > < / a > < span class = "lineno" > 461< / span >   < span class = "keywordflow" > if< / span > (ciphertext.empty())< / div >
< div class = "line" > < a name = "l00462" > < / a > < span class = "lineno" > 462< / span >   < span class = "keywordflow" > return< / span > ;< / div >
< div class = "line" > < a name = "l00463" > < / a > < span class = "lineno" > 463< / span >   < / div >
< div class = "line" > < a name = "l00464" > < / a > < span class = "lineno" > 464< / span >   Decrypt(ciphertext.data(), ciphertext.size(), & (*plaintext)[0]);< / div >
< div class = "line" > < a name = "l00465" > < / a > < span class = "lineno" > 465< / span >   }< / div >
< div class = "line" > < a name = "l00466" > < / a > < span class = "lineno" > 466< / span >   < / div >
< div class = "line" > < a name = "l00467" > < / a > < span class = "lineno" > < a class = "line" href = "../../dd/d96/classedash__packager_1_1media_1_1AesCbcCtsDecryptor.html#abcb9af2123d5ae47b2c89cf3feb67e06" > 467< / a > < / span >   < span class = "keywordtype" > bool< / span > AesCbcCtsDecryptor::SetIv(< span class = "keyword" > const< / span > std::vector< uint8_t> & iv) {< / div >
< div class = "line" > < a name = "l00468" > < / a > < span class = "lineno" > 468< / span >   < span class = "keywordflow" > if< / span > (iv.size() != AES_BLOCK_SIZE) {< / div >
< div class = "line" > < a name = "l00469" > < / a > < span class = "lineno" > 469< / span >   LOG(ERROR) < < < span class = "stringliteral" > " Invalid IV size: " < / span > < < iv.size();< / div >
< div class = "line" > < a name = "l00470" > < / a > < span class = "lineno" > 470< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > false< / span > ;< / div >
< div class = "line" > < a name = "l00471" > < / a > < span class = "lineno" > 471< / span >   }< / div >
< div class = "line" > < a name = "l00472" > < / a > < span class = "lineno" > 472< / span >   < / div >
< div class = "line" > < a name = "l00473" > < / a > < span class = "lineno" > 473< / span >   iv_ = iv;< / div >
< div class = "line" > < a name = "l00474" > < / a > < span class = "lineno" > 474< / span >   < span class = "keywordflow" > return< / span > < span class = "keyword" > true< / span > ;< / div >
< div class = "line" > < a name = "l00475" > < / a > < span class = "lineno" > 475< / span >   }< / div >
< div class = "line" > < a name = "l00476" > < / a > < span class = "lineno" > 476< / span >   < / div >
< div class = "line" > < a name = "l00477" > < / a > < span class = "lineno" > 477< / span >   } < span class = "comment" > // namespace media< / span > < / div >
< div class = "line" > < a name = "l00478" > < / a > < span class = "lineno" > 478< / span >   } < span class = "comment" > // namespace edash_packager< / span > < / div >
< / div > <!-- fragment --> < / div > <!-- contents -->
<!-- start footer part -->
< hr class = "footer" / > < address class = "footer" > < small >
2016-01-23 02:58:53 +00:00
Generated on Sat Jan 23 2016 02:58:43 for DASH Media Packaging SDK by   < a href = "http://www.doxygen.org/index.html" >
2015-10-16 00:33:37 +00:00
< img class = "footer" src = "../../doxygen.png" alt = "doxygen" / >
< / a > 1.8.6
< / small > < / address >
< / body >
< / html >
