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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// terms that can be accessed at https://unidoc.io/eula/

package crypt ;import (_b "crypto/aes";_ca "crypto/cipher";_g "crypto/md5";_f "crypto/rand";_c "crypto/rc4";_ec "fmt";_ef "github.com/unidoc/unipdf/v3/common";_d "github.com/unidoc/unipdf/v3/core/security";_a "io";);func init (){_gde ("\u0041\u0045\u0053V\u0032",_cab )};


// FilterDict represents information from a CryptFilter dictionary.
type FilterDict struct{CFM string ;AuthEvent _d .AuthEvent ;Length int ;};func (filterAES )EncryptBytes (buf []byte ,okey []byte )([]byte ,error ){_fe ,_fg :=_b .NewCipher (okey );if _fg !=nil {return nil ,_fg ;};_ef .Log .Trace ("A\u0045\u0053\u0020\u0045nc\u0072y\u0070\u0074\u0020\u0028\u0025d\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );
const _fc =_b .BlockSize ;_ac :=_fc -len (buf )%_fc ;for _da :=0;_da < _ac ;_da ++{buf =append (buf ,byte (_ac ));};_ef .Log .Trace ("\u0050a\u0064d\u0065\u0064\u0020\u0074\u006f \u0025\u0064 \u0062\u0079\u0074\u0065\u0073",len (buf ));_ga :=make ([]byte ,_fc +len (buf ));
_ba :=_ga [:_fc ];if _ ,_gg :=_a .ReadFull (_f .Reader ,_ba );_gg !=nil {return nil ,_gg ;};_fb :=_ca .NewCBCEncrypter (_fe ,_ba );_fb .CryptBlocks (_ga [_fc :],buf );buf =_ga ;_ef .Log .Trace ("\u0074\u006f\u0020(\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );
return buf ,nil ;};func _ad (_cf FilterDict )(Filter ,error ){if _cf .Length ==256{_ef .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",_cf .Length );
_cf .Length /=8;};if _cf .Length !=0&&_cf .Length !=32{return nil ,_ec .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",_cf .Length );
};return filterAESV3 {},nil ;};

// MakeKey implements Filter interface.
func (filterAESV3 )MakeKey (_ ,_ uint32 ,ekey []byte )([]byte ,error ){return ekey ,nil };type filterAESV3 struct{filterAES };

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

// EncryptBytes implements Filter interface.
func (filterV2 )EncryptBytes (buf []byte ,okey []byte )([]byte ,error ){_fcaf ,_db :=_c .NewCipher (okey );if _db !=nil {return nil ,_db ;};_ef .Log .Trace ("\u0052\u00434\u0020\u0045\u006ec\u0072\u0079\u0070\u0074\u003a\u0020\u0025\u0020\u0078",buf );
_fcaf .XORKeyStream (buf ,buf );_ef .Log .Trace ("\u0074o\u003a\u0020\u0025\u0020\u0078",buf );return buf ,nil ;};type filterV2 struct{_gae int };func (filterIdentity )KeyLength ()int {return 0};func init (){_gde ("\u0041\u0045\u0053V\u0033",_ad )};var _ Filter =filterV2 {};


// NewFilterAESV3 creates an AES-based filter with a 256 bit key (AESV3).
func NewFilterAESV3 ()Filter {_df ,_gee :=_ad (FilterDict {});if _gee !=nil {_ef .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",_gee );
return filterAESV3 {};};return _df ;};

// Name implements Filter interface.
func (filterV2 )Name ()string {return "\u0056\u0032"};var _ Filter =filterAESV3 {};

// 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 (_gd ,_dc uint32 ,_gedg []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 (_ceea []byte ,_ae []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 (_dfd []byte ,_cede []byte )([]byte ,error );};

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

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

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

// NewIdentity creates an identity filter that bypasses all data without changes.
func NewIdentity ()Filter {return filterIdentity {}};var (_cef =make (map[string ]filterFunc ););

// HandlerVersion implements Filter interface.
func (_bdc filterV2 )HandlerVersion ()(V ,R int ){V ,R =2,3;return ;};func _cab (_bd FilterDict )(Filter ,error ){if _bd .Length ==128{_ef .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",_bd .Length );
_bd .Length /=8;};if _bd .Length !=0&&_bd .Length !=16{return nil ,_ec .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",_bd .Length );
};return filterAESV2 {},nil ;};func init (){_gde ("\u0056\u0032",_ced )};func _ced (_eb FilterDict )(Filter ,error ){if _eb .Length %8!=0{return nil ,_ec .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",_eb .Length );
};if _eb .Length < 5||_eb .Length > 16{if _eb .Length ==40||_eb .Length ==64||_eb .Length ==128{_ef .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",_eb .Length );
_eb .Length /=8;}else {return nil ,_ec .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",_eb .Length );
};};return filterV2 {_gae :_eb .Length },nil ;};

// PDFVersion implements Filter interface.
func (filterAESV3 )PDFVersion ()[2]int {return [2]int {2,0}};func _fcg (_fge string )(filterFunc ,error ){_ddd :=_cef [_fge ];if _ddd ==nil {return nil ,_ec .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",_fge );
};return _ddd ,nil ;};func (filterIdentity )MakeKey (objNum ,genNum uint32 ,fkey []byte )([]byte ,error ){return fkey ,nil };

// NewFilterV2 creates a RC4-based filter with a specified key length (in bytes).
func NewFilterV2 (length int )Filter {_fcc ,_dg :=_ced (FilterDict {Length :length });if _dg !=nil {_ef .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",_dg );
return filterV2 {_gae :length };};return _fcc ;};

// KeyLength implements Filter interface.
func (filterAESV3 )KeyLength ()int {return 256/8};

// KeyLength implements Filter interface.
func (_cad filterV2 )KeyLength ()int {return _cad ._gae };

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

// MakeKey implements Filter interface.
func (_ffb filterV2 )MakeKey (objNum ,genNum uint32 ,ekey []byte )([]byte ,error ){return _gc (objNum ,genNum ,ekey ,false );};

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

// NewFilter creates CryptFilter from a corresponding dictionary.
func NewFilter (d FilterDict )(Filter ,error ){_dgb ,_gf :=_fcg (d .CFM );if _gf !=nil {return nil ,_gf ;};_afa ,_gf :=_dgb (d );if _gf !=nil {return nil ,_gf ;};return _afa ,nil ;};func (filterIdentity )EncryptBytes (p []byte ,okey []byte )([]byte ,error ){return p ,nil };
type filterAES struct{};func _gc (_cc ,_dd uint32 ,_cee []byte ,_fec bool )([]byte ,error ){_ea :=make ([]byte ,len (_cee )+5);for _ccg :=0;_ccg < len (_cee );_ccg ++{_ea [_ccg ]=_cee [_ccg ];};for _cg :=0;_cg < 3;_cg ++{_gbe :=byte ((_cc >>uint32 (8*_cg ))&0xff);
_ea [_cg +len (_cee )]=_gbe ;};for _gac :=0;_gac < 2;_gac ++{_bb :=byte ((_dd >>uint32 (8*_gac ))&0xff);_ea [_gac +len (_cee )+3]=_bb ;};if _fec {_ea =append (_ea ,0x73);_ea =append (_ea ,0x41);_ea =append (_ea ,0x6C);_ea =append (_ea ,0x54);};_eg :=_g .New ();
_eg .Write (_ea );_gea :=_eg .Sum (nil );if len (_cee )+5< 16{return _gea [0:len (_cee )+5],nil ;};return _gea ,nil ;};type filterAESV2 struct{filterAES };func (filterIdentity )DecryptBytes (p []byte ,okey []byte )([]byte ,error ){return p ,nil };func (filterIdentity )Name ()string {return "\u0049\u0064\u0065\u006e\u0074\u0069\u0074\u0079"};
var _ Filter =filterAESV2 {};

// MakeKey implements Filter interface.
func (filterAESV2 )MakeKey (objNum ,genNum uint32 ,ekey []byte )([]byte ,error ){return _gc (objNum ,genNum ,ekey ,true );};type filterFunc func (_ged FilterDict )(Filter ,error );func (filterIdentity )HandlerVersion ()(V ,R int ){return ;};func (filterAES )DecryptBytes (buf []byte ,okey []byte )([]byte ,error ){_bc ,_gab :=_b .NewCipher (okey );
if _gab !=nil {return nil ,_gab ;};if len (buf )< 16{_ef .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 ,_ec .Errorf ("\u0041\u0045\u0053\u003a B\u0075\u0066\u0020\u006c\u0065\u006e\u0020\u003c\u0020\u0031\u0036\u0020\u0028\u0025d\u0029",len (buf ));
};_ggb :=buf [:16];buf =buf [16:];if len (buf )%16!=0{_ef .Log .Debug ("\u0020\u0069\u0076\u0020\u0028\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (_ggb ),_ggb );_ef .Log .Debug ("\u0062\u0075\u0066\u0020\u0028\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );
return buf ,_ec .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 ));
};_fca :=_ca .NewCBCDecrypter (_bc ,_ggb );_ef .Log .Trace ("A\u0045\u0053\u0020\u0044ec\u0072y\u0070\u0074\u0020\u0028\u0025d\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );_ef .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 );
_fca .CryptBlocks (buf ,buf );_ef .Log .Trace ("\u0074\u006f\u0020(\u0025\u0064\u0029\u003a\u0020\u0025\u0020\u0078",len (buf ),buf );if len (buf )==0{_ef .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 ;};_fff :=int (buf [len (buf )-1]);if _fff > len (buf ){_ef .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",_fff ,len (buf ));
return buf ,_ec .Errorf ("\u0069n\u0076a\u006c\u0069\u0064\u0020\u0070a\u0064\u0020l\u0065\u006e\u0067\u0074\u0068");};buf =buf [:len (buf )-_fff ];return buf ,nil ;};

// HandlerVersion implements Filter interface.
func (filterAESV3 )HandlerVersion ()(V ,R int ){V ,R =5,6;return ;};func _gde (_ed string ,_de filterFunc ){if _ ,_geaf :=_cef [_ed ];_geaf {panic ("\u0061l\u0072e\u0061\u0064\u0079\u0020\u0072e\u0067\u0069s\u0074\u0065\u0072\u0065\u0064");};_cef [_ed ]=_de ;
};

// KeyLength implements Filter interface.
func (filterAESV2 )KeyLength ()int {return 128/8};type filterIdentity struct{};

// NewFilterAESV2 creates an AES-based filter with a 128 bit key (AESV2).
func NewFilterAESV2 ()Filter {_ff ,_fa :=_cab (FilterDict {});if _fa !=nil {_ef .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",_fa );
return filterAESV2 {};};return _ff ;};func (filterIdentity )PDFVersion ()[2]int {return [2]int {}};