unipdf/core/security/crypt/crypt.go

//
// Copyright 2020 FoxyUtils ehf. All rights reserved.
//
// This is a commercial product and requires a license to operate.
// A trial license can be obtained at https://unidoc.io
//
// DO NOT EDIT: generated by unitwist Go source code obfuscator.
//
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package crypt ;import (_eg "crypto/aes";_gd "crypto/cipher";_g "crypto/md5";_ag "crypto/rand";_ec "crypto/rc4";_a "fmt";_b "github.com/unidoc/unipdf/v3/common";_fe "github.com/unidoc/unipdf/v3/core/security";_e "io";);func init (){_egf ("\u0041\u0045\u0053V\u0032",_c )};
var _ Filter =filterAESV2 {};type filterV2 struct{_fc int };

// NewFilterAESV3 creates an AES-based filter with a 256 bit key (AESV3).
func NewFilterAESV3 ()Filter {_bd ,_bde :=_dd (FilterDict {});if _bde !=nil {_b .Log .Error ("E\u0052\u0052\u004f\u0052\u003a\u0020\u0063\u006f\u0075l\u0064\u0020\u006e\u006f\u0074\u0020\u0063re\u0061\u0074\u0065\u0020A\u0045\u0053\u0020\u0056\u0033\u0020\u0063\u0072\u0079pt\u0020\u0066i\u006c\u0074\u0065\u0072\u003a\u0020\u0025\u0076",_bde );
return filterAESV3 {};};return _bd ;};type filterAES struct{};

// MakeKey implements Filter interface.
func (filterAESV2 )MakeKey (objNum ,genNum uint32 ,ekey []byte )([]byte ,error ){return _ba (objNum ,genNum ,ekey ,true );};func (filterIdentity )MakeKey (objNum ,genNum uint32 ,fkey []byte )([]byte ,error ){return fkey ,nil };func (filterAES )DecryptBytes (buf []byte ,okey []byte )([]byte ,error ){_ac ,_ecg :=_eg .NewCipher (okey );
if _ecg !=nil {return nil ,_ecg ;};if len (buf )< 16{_b .Log .Debug ("\u0045R\u0052\u004f\u0052\u0020\u0041\u0045\u0053\u0020\u0069\u006e\u0076a\u006c\u0069\u0064\u0020\u0062\u0075\u0066\u0020\u0025\u0073",buf );return buf ,_a .Errorf ("\u0041\u0045\u0053\u003a B\u0075\u0066\u0020\u006c\u0065\u006e\u0020\u003c\u0020\u0031\u0036\u0020\u0028\u0025d\u0029",len (buf ));
};_ecb :=buf [:16];buf =buf [16:];if len (buf )%16!=0{_b .Log .Debug ("\u0020\u0069\u0076\u0020\u0028\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (_ecb ),_ecb );_b .Log .Debug ("\u0062\u0075\u0066\u0020\u0028\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );
return buf ,_a .Errorf ("\u0041\u0045\u0053\u0020\u0062\u0075\u0066\u0020\u006c\u0065\u006e\u0067\u0074\u0068\u0020\u006e\u006f\u0074\u0020\u006d\u0075\u006c\u0074\u0069p\u006c\u0065\u0020\u006f\u0066 \u0031\u0036 \u0028\u0025\u0064\u0029",len (buf ));
};_ee :=_gd .NewCBCDecrypter (_ac ,_ecb );_b .Log .Trace ("A\u0045\u0053\u0020\u0044ec\u0072y\u0070\u0074\u0020\u0028\u0025d\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );_b .Log .Trace ("\u0063\u0068\u006f\u0070\u0020\u0041\u0045\u0053\u0020\u0044\u0065c\u0072\u0079\u0070\u0074\u0020\u0028\u0025\u0064\u0029\u003a \u0025\u0020\u0078",len (buf ),buf );
_ee .CryptBlocks (buf ,buf );_b .Log .Trace ("\u0074\u006f\u0020(\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );if len (buf )==0{_b .Log .Trace ("\u0045\u006d\u0070\u0074\u0079\u0020b\u0075\u0066\u002c\u0020\u0072\u0065\u0074\u0075\u0072\u006e\u0069\u006e\u0067 \u0065\u006d\u0070\u0074\u0079\u0020\u0073t\u0072\u0069\u006e\u0067");
return buf ,nil ;};_dc :=int (buf [len (buf )-1]);if _dc > len (buf ){_b .Log .Debug ("\u0049\u006c\u006c\u0065g\u0061\u006c\u0020\u0070\u0061\u0064\u0020\u006c\u0065\u006eg\u0074h\u0020\u0028\u0025\u0064\u0020\u003e\u0020%\u0064\u0029",_dc ,len (buf ));
return buf ,_a .Errorf ("\u0069n\u0076a\u006c\u0069\u0064\u0020\u0070a\u0064\u0020l\u0065\u006e\u0067\u0074\u0068");};buf =buf [:len (buf )-_dc ];return buf ,nil ;};func _egf (_bcd string ,_efc filterFunc ){if _ ,_ea :=_bcg [_bcd ];_ea {panic ("\u0061l\u0072e\u0061\u0064\u0079\u0020\u0072e\u0067\u0069s\u0074\u0065\u0072\u0065\u0064");
};_bcg [_bcd ]=_efc ;};func (filterIdentity )KeyLength ()int {return 0};func init (){_egf ("\u0041\u0045\u0053V\u0033",_dd )};

// Name implements Filter interface.
func (filterAESV2 )Name ()string {return "\u0041\u0045\u0053V\u0032"};

// PDFVersion implements Filter interface.
func (filterAESV3 )PDFVersion ()[2]int {return [2]int {2,0}};

// KeyLength implements Filter interface.
func (_ecba filterV2 )KeyLength ()int {return _ecba ._fc };

// HandlerVersion implements Filter interface.
func (filterAESV3 )HandlerVersion ()(V ,R int ){V ,R =5,6;return ;};

// Name implements Filter interface.
func (filterV2 )Name ()string {return "\u0056\u0032"};

// FilterDict represents information from a CryptFilter dictionary.
type FilterDict struct{CFM string ;AuthEvent _fe .AuthEvent ;Length int ;};

// MakeKey implements Filter interface.
func (_bb filterV2 )MakeKey (objNum ,genNum uint32 ,ekey []byte )([]byte ,error ){return _ba (objNum ,genNum ,ekey ,false );};func (filterIdentity )DecryptBytes (p []byte ,okey []byte )([]byte ,error ){return p ,nil };func _ba (_ddaa ,_ddc uint32 ,_bfe []byte ,_bdf bool )([]byte ,error ){_dgf :=make ([]byte ,len (_bfe )+5);
for _ge :=0;_ge < len (_bfe );_ge ++{_dgf [_ge ]=_bfe [_ge ];};for _bgd :=0;_bgd < 3;_bgd ++{_ff :=byte ((_ddaa >>uint32 (8*_bgd ))&0xff);_dgf [_bgd +len (_bfe )]=_ff ;};for _ca :=0;_ca < 2;_ca ++{_ed :=byte ((_ddc >>uint32 (8*_ca ))&0xff);_dgf [_ca +len (_bfe )+3]=_ed ;
};if _bdf {_dgf =append (_dgf ,0x73);_dgf =append (_dgf ,0x41);_dgf =append (_dgf ,0x6C);_dgf =append (_dgf ,0x54);};_eeg :=_g .New ();_eeg .Write (_dgf );_gc :=_eeg .Sum (nil );if len (_bfe )+5< 16{return _gc [0:len (_bfe )+5],nil ;};return _gc ,nil ;
};var (_bcg =make (map[string ]filterFunc ););func (filterIdentity )EncryptBytes (p []byte ,okey []byte )([]byte ,error ){return p ,nil };type filterFunc func (_cgd FilterDict )(Filter ,error );func init (){_egf ("\u0056\u0032",_gf )};

// Name implements Filter interface.
func (filterAESV3 )Name ()string {return "\u0041\u0045\u0053V\u0033"};

// HandlerVersion implements Filter interface.
func (_fed filterV2 )HandlerVersion ()(V ,R int ){V ,R =2,3;return ;};func _c (_gb FilterDict )(Filter ,error ){if _gb .Length ==128{_b .Log .Debug ("\u0041\u0045S\u0056\u0032\u0020c\u0072\u0079\u0070\u0074\u0020f\u0069\u006c\u0074\u0065\u0072 l\u0065\u006e\u0067\u0074\u0068\u0020\u0061\u0070\u0070\u0065\u0061\u0072\u0073\u0020\u0074\u006f\u0020\u0062e\u0020i\u006e\u0020\u0062\u0069\u0074\u0073 ra\u0074\u0068\u0065\u0072\u0020\u0074\u0068\u0061\u006e\u0020\u0062\u0079te\u0073 \u002d\u0020\u0061\u0073s\u0075m\u0069n\u0067\u0020b\u0069\u0074s \u0028\u0025\u0064\u0029",_gb .Length );
_gb .Length /=8;};if _gb .Length !=0&&_gb .Length !=16{return nil ,_a .Errorf ("\u0069\u006e\u0076\u0061\u006c\u0069\u0064\u0020\u0041\u0045\u0053\u0056\u0032\u0020\u0063\u0072\u0079\u0070\u0074\u0020\u0066\u0069\u006c\u0074e\u0072\u0020\u006c\u0065\u006eg\u0074\u0068 \u0028\u0025\u0064\u0029",_gb .Length );
};return filterAESV2 {},nil ;};var _ Filter =filterV2 {};func (filterIdentity )PDFVersion ()[2]int {return [2]int {}};

// MakeKey implements Filter interface.
func (filterAESV3 )MakeKey (_ ,_ uint32 ,ekey []byte )([]byte ,error ){return ekey ,nil };func (filterIdentity )Name ()string {return "\u0049\u0064\u0065\u006e\u0074\u0069\u0074\u0079"};func (filterAES )EncryptBytes (buf []byte ,okey []byte )([]byte ,error ){_ce ,_bg :=_eg .NewCipher (okey );
if _bg !=nil {return nil ,_bg ;};_b .Log .Trace ("A\u0045\u0053\u0020\u0045nc\u0072y\u0070\u0074\u0020\u0028\u0025d\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );const _ad =_eg .BlockSize ;_fad :=_ad -len (buf )%_ad ;for _df :=0;_df < _fad ;_df ++{buf =append (buf ,byte (_fad ));
};_b .Log .Trace ("\u0050a\u0064d\u0065\u0064\u0020\u0074\u006f \u0025\u0064 \u0062\u0079\u0074\u0065\u0073",len (buf ));_fee :=make ([]byte ,_ad +len (buf ));_dda :=_fee [:_ad ];if _ ,_dg :=_e .ReadFull (_ag .Reader ,_dda );_dg !=nil {return nil ,_dg ;
};_af :=_gd .NewCBCEncrypter (_ce ,_dda );_af .CryptBlocks (_fee [_ad :],buf );buf =_fee ;_b .Log .Trace ("\u0074\u006f\u0020(\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );return buf ,nil ;};

// NewFilterV2 creates a RC4-based filter with a specified key length (in bytes).
func NewFilterV2 (length int )Filter {_bc ,_eff :=_gf (FilterDict {Length :length });if _eff !=nil {_b .Log .Error ("E\u0052\u0052\u004f\u0052\u003a\u0020\u0063\u006f\u0075l\u0064\u0020\u006e\u006f\u0074\u0020\u0063re\u0061\u0074\u0065\u0020R\u0043\u0034\u0020\u0056\u0032\u0020\u0063\u0072\u0079pt\u0020\u0066i\u006c\u0074\u0065\u0072\u003a\u0020\u0025\u0076",_eff );
return filterV2 {_fc :length };};return _bc ;};

// DecryptBytes implements Filter interface.
func (filterV2 )DecryptBytes (buf []byte ,okey []byte )([]byte ,error ){_ga ,_db :=_ec .NewCipher (okey );if _db !=nil {return nil ,_db ;};_b .Log .Trace ("\u0052\u00434\u0020\u0044\u0065c\u0072\u0079\u0070\u0074\u003a\u0020\u0025\u0020\u0078",buf );_ga .XORKeyStream (buf ,buf );
_b .Log .Trace ("\u0074o\u003a\u0020\u0025\u0020\u0078",buf );return buf ,nil ;};

// NewIdentity creates an identity filter that bypasses all data without changes.
func NewIdentity ()Filter {return filterIdentity {}};

// NewFilter creates CryptFilter from a corresponding dictionary.
func NewFilter (d FilterDict )(Filter ,error ){_da ,_gec :=_gdg (d .CFM );if _gec !=nil {return nil ,_gec ;};_ddg ,_gec :=_da (d );if _gec !=nil {return nil ,_gec ;};return _ddg ,nil ;};

// Filter is a common interface for crypt filter methods.
type Filter interface{

// Name returns a name of the filter that should be used in CFM field of Encrypt dictionary.
Name ()string ;

// KeyLength returns a length of the encryption key in bytes.
KeyLength ()int ;

// PDFVersion reports the minimal version of PDF document that introduced this filter.
PDFVersion ()[2]int ;

// HandlerVersion reports V and R parameters that should be used for this filter.
HandlerVersion ()(V ,R int );

// MakeKey generates a object encryption key based on file encryption key and object numbers.
// Used only for legacy filters - AESV3 doesn't change the key for each object.
MakeKey (_gfg ,_ffd uint32 ,_fedc []byte )([]byte ,error );

// EncryptBytes encrypts a buffer using object encryption key, as returned by MakeKey.
// Implementation may reuse a buffer and encrypt data in-place.
EncryptBytes (_fdg []byte ,_be []byte )([]byte ,error );

// DecryptBytes decrypts a buffer using object encryption key, as returned by MakeKey.
// Implementation may reuse a buffer and decrypt data in-place.
DecryptBytes (_adc []byte ,_fdb []byte )([]byte ,error );};

// HandlerVersion implements Filter interface.
func (filterAESV2 )HandlerVersion ()(V ,R int ){V ,R =4,4;return ;};func (filterIdentity )HandlerVersion ()(V ,R int ){return ;};var _ Filter =filterAESV3 {};

// NewFilterAESV2 creates an AES-based filter with a 128 bit key (AESV2).
func NewFilterAESV2 ()Filter {_ef ,_d :=_c (FilterDict {});if _d !=nil {_b .Log .Error ("E\u0052\u0052\u004f\u0052\u003a\u0020\u0063\u006f\u0075l\u0064\u0020\u006e\u006f\u0074\u0020\u0063re\u0061\u0074\u0065\u0020A\u0045\u0053\u0020\u0056\u0032\u0020\u0063\u0072\u0079pt\u0020\u0066i\u006c\u0074\u0065\u0072\u003a\u0020\u0025\u0076",_d );
return filterAESV2 {};};return _ef ;};

// KeyLength implements Filter interface.
func (filterAESV2 )KeyLength ()int {return 128/8};type filterAESV3 struct{filterAES };type filterIdentity struct{};func _dd (_fa FilterDict )(Filter ,error ){if _fa .Length ==256{_b .Log .Debug ("\u0041\u0045S\u0056\u0033\u0020c\u0072\u0079\u0070\u0074\u0020f\u0069\u006c\u0074\u0065\u0072 l\u0065\u006e\u0067\u0074\u0068\u0020\u0061\u0070\u0070\u0065\u0061\u0072\u0073\u0020\u0074\u006f\u0020\u0062e\u0020i\u006e\u0020\u0062\u0069\u0074\u0073 ra\u0074\u0068\u0065\u0072\u0020\u0074\u0068\u0061\u006e\u0020\u0062\u0079te\u0073 \u002d\u0020\u0061\u0073s\u0075m\u0069n\u0067\u0020b\u0069\u0074s \u0028\u0025\u0064\u0029",_fa .Length );
_fa .Length /=8;};if _fa .Length !=0&&_fa .Length !=32{return nil ,_a .Errorf ("\u0069\u006e\u0076\u0061\u006c\u0069\u0064\u0020\u0041\u0045\u0053\u0056\u0033\u0020\u0063\u0072\u0079\u0070\u0074\u0020\u0066\u0069\u006c\u0074e\u0072\u0020\u006c\u0065\u006eg\u0074\u0068 \u0028\u0025\u0064\u0029",_fa .Length );
};return filterAESV3 {},nil ;};

// EncryptBytes implements Filter interface.
func (filterV2 )EncryptBytes (buf []byte ,okey []byte )([]byte ,error ){_cfa ,_bae :=_ec .NewCipher (okey );if _bae !=nil {return nil ,_bae ;};_b .Log .Trace ("\u0052\u00434\u0020\u0045\u006ec\u0072\u0079\u0070\u0074\u003a\u0020\u0025\u0020\u0078",buf );
_cfa .XORKeyStream (buf ,buf );_b .Log .Trace ("\u0074o\u003a\u0020\u0025\u0020\u0078",buf );return buf ,nil ;};type filterAESV2 struct{filterAES };

// PDFVersion implements Filter interface.
func (filterAESV2 )PDFVersion ()[2]int {return [2]int {1,5}};

// PDFVersion implements Filter interface.
func (_dgd filterV2 )PDFVersion ()[2]int {return [2]int {}};

// KeyLength implements Filter interface.
func (filterAESV3 )KeyLength ()int {return 256/8};func _gdg (_agd string )(filterFunc ,error ){_de :=_bcg [_agd ];if _de ==nil {return nil ,_a .Errorf ("\u0075\u006e\u0073\u0075p\u0070\u006f\u0072\u0074\u0065\u0064\u0020\u0063\u0072\u0079p\u0074 \u0066\u0069\u006c\u0074\u0065\u0072\u003a \u0025\u0071",_agd );
};return _de ,nil ;};func _gf (_ade FilterDict )(Filter ,error ){if _ade .Length %8!=0{return nil ,_a .Errorf ("\u0063\u0072\u0079p\u0074\u0020\u0066\u0069\u006c\u0074\u0065\u0072\u0020\u006c\u0065\u006e\u0067\u0074\u0068\u0020\u006e\u006f\u0074\u0020\u006d\u0075\u006c\u0074\u0069\u0070\u006c\u0065\u0020o\u0066\u0020\u0038\u0020\u0028\u0025\u0064\u0029",_ade .Length );
};if _ade .Length < 5||_ade .Length > 16{if _ade .Length ==40||_ade .Length ==64||_ade .Length ==128{_b .Log .Debug ("\u0053\u0054\u0041\u004e\u0044AR\u0044\u0020V\u0049\u004f\u004c\u0041\u0054\u0049\u004f\u004e\u003a\u0020\u0043\u0072\u0079\u0070\u0074\u0020\u004c\u0065\u006e\u0067\u0074\u0068\u0020\u0061\u0070\u0070\u0065\u0061\u0072s\u0020\u0074\u006f \u0062\u0065\u0020\u0069\u006e\u0020\u0062\u0069\u0074\u0073\u0020\u0072\u0061t\u0068\u0065\u0072\u0020\u0074h\u0061\u006e\u0020\u0062\u0079\u0074\u0065\u0073\u0020-\u0020\u0061s\u0073u\u006d\u0069\u006e\u0067\u0020\u0062\u0069t\u0073\u0020\u0028\u0025\u0064\u0029",_ade .Length );
_ade .Length /=8;}else {return nil ,_a .Errorf ("\u0063\u0072\u0079\u0070\u0074\u0020\u0066\u0069\u006c\u0074\u0065\u0072\u0020\u006c\u0065\u006e\u0067\u0074h\u0020\u006e\u006f\u0074\u0020\u0069\u006e \u0072\u0061\u006e\u0067\u0065\u0020\u0034\u0030\u0020\u002d\u00201\u0032\u0038\u0020\u0062\u0069\u0074\u0020\u0028\u0025\u0064\u0029",_ade .Length );
};};return filterV2 {_fc :_ade .Length },nil ;};