libp2p/crypto/minasn1

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This module implements minimal ASN.1 encoding/decoding primitives.

Types

Asn1Buffer = object of RootObj
  buffer*: seq[byte]
  offset*: int
  length*: int
ASN.1's message representation object Source   Edit   
Asn1Class {.pure.} = enum
  Universal = 0, Application = 1, ContextSpecific = 2, Private = 3
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Asn1Composite = object of Asn1Buffer
  tag*: Asn1Tag
  idx*: int
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Asn1Error {.pure.} = enum
  Overflow, Incomplete, Indefinite, Incorrect, NoSupport, Overrun
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Asn1Field = object
  klass*: Asn1Class
  index*: int
  offset*: int
  length*: int
  buffer*: seq[byte]
  case kind*: Asn1Tag
  of Asn1Tag.Boolean:
      vbool*: bool

  of Asn1Tag.Integer:
      vint*: uint64

  of Asn1Tag.BitString:
      ubits*: int

  else:
      nil
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Asn1Result[T] = Result[T, Asn1Error]
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Asn1Tag {.pure.} = enum
  NoSupport, Boolean, Integer, BitString, OctetString, Null, Oid, Sequence,
  Context
Protobuf's field types enum Source   Edit  

Consts

Asn1False = [0x01'u8, 0x01'u8, 0x00'u8]
Encoded boolean FALSE. Source   Edit   
Asn1Null = [0x05'u8, 0x00'u8]
Encoded NULL value. Source   Edit   
Asn1OidEcPublicKey = [0x2A'u8, 0x86'u8, 0x48'u8, 0xCE'u8, 0x3D'u8, 0x02'u8,
                      0x01'u8]
Encoded OID for Elliptic Curve Public Key (1.2.840.10045.2.1) Source   Edit   
Asn1OidRsaEncryption = [0x2A'u8, 0x86'u8, 0x48'u8, 0x86'u8, 0xF7'u8, 0x0D'u8,
                        0x01'u8, 0x01'u8, 0x01'u8]
Encoded OID for RSA Encryption (1.2.840.113549.1.1.1) Source   Edit   
Asn1OidSecp256k1 = [0x2B'u8, 0x81'u8, 0x04'u8, 0x00'u8, 0x0A'u8]
Encoded OID for secp256k1 curve (1.3.132.0.10) Source   Edit   
Asn1OidSecp256r1 = [0x2A'u8, 0x86'u8, 0x48'u8, 0xCE'u8, 0x3D'u8, 0x03'u8,
                    0x01'u8, 0x07'u8]
Encoded OID for secp256r1 curve (1.2.840.10045.3.1.7) Source   Edit   
Asn1OidSecp384r1 = [0x2B'u8, 0x81'u8, 0x04'u8, 0x00'u8, 0x22'u8]
Encoded OID for secp384r1 curve (1.3.132.0.34) Source   Edit   
Asn1OidSecp521r1 = [0x2B'u8, 0x81'u8, 0x04'u8, 0x00'u8, 0x23'u8]
Encoded OID for secp521r1 curve (1.3.132.0.35) Source   Edit   
Asn1True = [0x01'u8, 0x01'u8, 0xFF'u8]
Encoded boolean TRUE. Source   Edit  

Procs

proc `$`(buffer: Asn1Buffer): string {....raises: [], tags: [], forbids: [].}
Return string representation of buffer. Source   Edit   
proc `$`(field: Asn1Field): string {....raises: [], tags: [], forbids: [].}
Return string representation of field. Source   Edit   
proc `==`(field: Asn1Field; data: openArray[byte]): bool {....raises: [], tags: [],
    forbids: [].}
Compares field field data with data and returns true if both buffers are equal. Source   Edit   
proc asn1EncodeBitString(dest: var openArray[byte]; value: openArray[byte];
                         bits = 0): int {....raises: [], tags: [], forbids: [].}

Encode array of bytes as ASN.1 DER BIT STRING and return number of bytes (octets) used.

bits number of unused bits in value. If bits == 0, all the bits from value will be used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeBoolean(dest: var openArray[byte]; value: bool): int {.
    ...raises: [], tags: [], forbids: [].}

Encode Nim's boolean as ASN.1 DER BOOLEAN and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeComposite(dest: var openArray[byte]; value: Asn1Composite): int {.
    ...raises: [], tags: [], forbids: [].}

Encode composite value and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeContextTag(dest: var openArray[byte]; value: openArray[byte];
                          tag: int): int {....raises: [], tags: [], forbids: [].}

Encode ASN.1 DER CONTEXT SPECIFIC TAG tag for value value and return number of bytes (octets) used.

Note: Only values in 0, 15 range can be used as context tag tag values.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeInteger(dest: var openArray[byte]; value: openArray[byte]): int {.
    ...raises: [], tags: [], forbids: [].}

Encode big-endian binary representation of integer as ASN.1 DER INTEGER and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding WILL NOT BE stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeInteger[T: SomeUnsignedInt](dest: var openArray[byte]; value: T): int {.
    ...raises: [].}

Encode Nim's unsigned integer as ASN.1 DER INTEGER and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeLength(dest: var openArray[byte]; length: uint64): int {.
    ...raises: [], tags: [], forbids: [].}

Encode ASN.1 DER length part of TLV triple and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode length value, then result of encoding WILL NOT BE stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeNull(dest: var openArray[byte]): int {....raises: [], tags: [],
    forbids: [].}

Encode ASN.1 DER NULL and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeOctetString(dest: var openArray[byte]; value: openArray[byte]): int {.
    ...raises: [], tags: [], forbids: [].}

Encode array of bytes as ASN.1 DER OCTET STRING and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeOid(dest: var openArray[byte]; value: openArray[byte]): int {.
    ...raises: [], tags: [], forbids: [].}

Encode array of bytes value as ASN.1 DER OBJECT IDENTIFIER and return number of bytes (octets) used.

This procedure is useful to encode constant predefined identifiers such as asn1OidSecp256r1, asn1OidRsaEncryption.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc asn1EncodeSequence(dest: var openArray[byte]; value: openArray[byte]): int {.
    ...raises: [], tags: [], forbids: [].}

Encode value as ASN.1 DER SEQUENCE and return number of bytes (octets) used.

If length of dest is less then number of required bytes to encode value, then result of encoding will not be stored in dest but number of bytes (octets) required will be returned.

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proc code(tag: Asn1Tag): byte {.inline, ...raises: [], tags: [], forbids: [].}
Converts Nim tag enum to ASN.1 tag code. Source   Edit   
proc extend[T: Asn1Buffer | Asn1Composite](abc: var T; length: int) {.inline,
    ...raises: [].}
Extend buffer or composite's internal buffer by length octets. Source   Edit   
proc finish[T: Asn1Buffer | Asn1Composite](abc: var T) {.inline, ...raises: [].}
Finishes buffer or composite and prepares it for writing. Source   Edit   
proc getBuffer(field: Asn1Field): Asn1Buffer {.inline, ...raises: [], tags: [],
    forbids: [].}
Return field as Asn1Buffer to enter composite types. Source   Edit   
proc init(t: typedesc[Asn1Buffer]): Asn1Buffer {....raises: [].}
Initialize empty Asn1Buffer. Source   Edit   
proc init(t: typedesc[Asn1Buffer]; data: openArray[byte]): Asn1Buffer {.
    ...raises: [].}
Initialize Asn1Buffer from array of bytes data. Source   Edit   
proc init(t: typedesc[Asn1Buffer]; data: string): Asn1Buffer {....raises: [].}
Initialize Asn1Buffer from hexadecimal string data. Source   Edit   
proc init(t: typedesc[Asn1Composite]; idx: int): Asn1Composite {....raises: [].}
Initialize Asn1Composite with tag context-specific id id. Source   Edit   
proc init(t: typedesc[Asn1Composite]; tag: Asn1Tag): Asn1Composite {....raises: [].}
Initialize Asn1Composite with tag tag. Source   Edit   
proc len(field: Asn1Field): int {.inline, ...raises: [], tags: [], forbids: [].}
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proc len[T: Asn1Buffer | Asn1Composite](abc: T): int {.inline, ...raises: [].}
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proc read(ab: var Asn1Buffer): Asn1Result[Asn1Field] {....raises: [], tags: [],
    forbids: [].}
Decode value part of ASN.1 TLV triplet. Source   Edit   
proc write[T: Asn1Buffer | Asn1Composite](abc: var T; tag: Asn1Tag) {....raises: [].}

Write empty value to buffer or composite with tag.

This procedure must be used to write NULL, 0 or empty BIT STRING, OCTET STRING types.

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proc write[T: Asn1Buffer | Asn1Composite](abc: var T; tag: Asn1Tag;
    value: openArray[byte]; bits = 0) {....raises: [].}

Write array value using tag.

This procedure is used to write ASN.1 INTEGER, OCTET STRING, BIT STRING or OBJECT IDENTIFIER.

For BIT STRING you can use bits argument to specify number of used bits.

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proc write[T: Asn1Buffer | Asn1Composite](abc: var T; value: Asn1Composite) {.
    ...raises: [].}
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proc write[T: Asn1Buffer | Asn1Composite](abc: var T; value: bool) {....raises: [].}
Write bool value to buffer or composite as ASN.1 BOOLEAN. Source   Edit   
proc write[T: Asn1Buffer | Asn1Composite](abc: var T; value: uint64) {.
    ...raises: [].}
Write uint64 value to buffer or composite as ASN.1 INTEGER. Source   Edit  

Templates

template getPtr(field: untyped): pointer
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template isEmpty(ab: Asn1Buffer): bool
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template isEnough(ab: Asn1Buffer; length: int64): bool
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template toOpenArray(ab: Asn1Buffer): untyped
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template toOpenArray(ac: Asn1Composite): untyped
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template toOpenArray(af: Asn1Field): untyped
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Made with Nim. Generated: 2023-10-11 13:33:29 UTC