vtag

Documentation

Overview

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License

Copyright (c) 2026 Christopher J Bearman

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Index

• Constants
• Variables
• type APDUError
  • func (e APDUError) Error() string
• type OnCardFunc
• type Scanner
  • func NewScanner() *Scanner
  • func (s *Scanner) Close()
  • func (s *Scanner) OnCard(do OnCardFunc) error
• type Session
  • func (s *Session) GetATR() string
  • func (s *Session) GetTag() *Tag
  • func (s *Session) Read(start int, length int) ([]byte, error)
  • func (s *Session) Write(start int, data []byte) error
• type Tag
  • func (t *Tag) BlockSize() int
  • func (t *Tag) GetAvailableBytes() int
  • func (t *Tag) GetTagType() TagType
  • func (t *Tag) GetUID() []byte
  • func (t *Tag) GetUIDHex() string
  • func (t *Tag) NBlocks() uint16
• type TagType
  • func (t TagType) String() string

Constants

const MaxReadWriteMultiDataSize = 120

MaxReadWriteMultiDataSize is the maximum data size for read/write multiple blocks basically a limit that can be supported by the PC/SC and ACR1552-U

Variables

var DebugMode = false

DebugMode can be set to true for debug logging, which is really useful for development

Types

type APDUError

type APDUError struct {
	Status [2]byte
}

APDUYError represents an error response from an APDU command

func (APDUError) Error

func (e APDUError) Error() string

type OnCardFunc

type OnCardFunc func(*Session) error

OnCardFunc must be implemented by the caller of the OnCard callback

type Scanner

type Scanner struct {
	// contains filtered or unexported fields
}

Scanner implements the interface to the PCSC interface

func NewScanner

func NewScanner() *Scanner

NewScanner creates a new scanner connection

func (*Scanner) Close

func (s *Scanner) Close()

Close must be called to close down our goroutine

func (*Scanner) OnCard

func (s *Scanner) OnCard(do OnCardFunc) error

OnCard should be called to provide a callback function which will be called whenever a card is applied to the reader

type Session

type Session struct {
	// contains filtered or unexported fields
}

A Session represents a communications session to a card applied to the reader

func (*Session) GetATR

func (s *Session) GetATR() string

GetATR returns the ATR for the card associated with the session

func (*Session) GetTag

func (s *Session) GetTag() *Tag

GetTag returns tag information for the card associated with the session

func (*Session) Read

func (s *Session) Read(start int, length int) ([]byte, error)

Read reads length bytes from the specified start address byte No block alignment is required for reads

func (*Session) Write

func (s *Session) Write(start int, data []byte) error

Write will write the provided data at the specified byte address start must be block aligned If data is not multiple of block size, it will be padded to block size with 0x00 bytes

type Tag

type Tag struct {
	// contains filtered or unexported fields
}

Tag represents an instance of a tag

func (*Tag) BlockSize

func (t *Tag) BlockSize() int

BlockSize returns the number of bytes per block supported by the tag

func (*Tag) GetAvailableBytes

func (t *Tag) GetAvailableBytes() int

GetAvailableBytes returns the number of bytes available for reading/writing user data

func (*Tag) GetTagType

func (t *Tag) GetTagType() TagType

GetTagType returns the type of tag

func (*Tag) GetUID

func (t *Tag) GetUID() []byte

GetUID returns the UID for the tag

func (*Tag) GetUIDHex

func (t *Tag) GetUIDHex() string

GetUIDHex returns the UID for the tag, hex formatted

func (*Tag) NBlocks

func (t *Tag) NBlocks() uint16

NBlocks returns the number of blocks supported by the tag

type TagType

type TagType uint8

TagType enumerates the supported tags

const (
	UNKNOWN   TagType = iota
	ICODE_SLI         // N.B. untested
	ICODE_SLIX
	ICODE_SLIX2
	ST25DV04 // N.B. untested
	ST25DV16
	ST25DV64 // N.B. untested
)

func (TagType) String

func (t TagType) String() string

TagType returns a string representation of the TagType