Add 2D-DOC Support

README.md

@@ -4,7 +4,7 @@ Golang implementation of the covid certificates. At the moment it only includes
 
 ## Features
 - Decode signed DCC (European QRCodes) data ✅
-- Decode 2D-DOC data ❌ (planned)
+- Decode 2D-DOC data ✅
 - Pretty-print decoded data as JSON ✅
 - Download public-keys from european gateway ❌ (planned)
 - Verify signature ❌ (planned)
@@ -15,10 +15,10 @@ Golang implementation of the covid certificates. At the moment it only includes
 ## Usage
 `gocovidcertificate <flags>`
 
-| Flag   | Type   | Description              | Required | Default value |
-| ------ | ------ | ------------------------ | -------- | ------------- |
-| -code  | string | QRCode string to decode  | true     | none          |
-| -print | bool   | Prints the QRCode data to console | false | true    |
+| Flag   | Type   | Description                                               | Required | Default value |
+| ------ | ------ | --------------------------------------------------------- | -------- | ------------- |
+| -code  | string | QRCode data to decode (put it between double-quotes `""`) | true     | none          |
+| -print | bool   | Prints the QRCode data to console                         | false    | true          |
 
 Example:  
 `gocovidcertificate -code "HC1:..." -print`

decoders/2ddoc.go

@@ -0,0 +1,86 @@
+package decoders
+
+import (
+	"encoding/json"
+	"github.com/alexpresso/gocovidcertificate/types"
+	"github.com/alexpresso/gocovidcertificate/utils"
+	"strconv"
+	"strings"
+)
+
+var TwoDPrefix = "DC"
+
+func twoDDocDecode(input string) (certificate *types.Certificate, err error) {
+	header, remaining, err := decodeHeader(input)
+	if err != nil {
+		return nil, err
+	}
+
+	message, signature, err := decodeData(remaining)
+	if err != nil {
+		return nil, err
+	}
+
+	return &types.Certificate{
+		Type: types.TWODDOC,
+		Data: &types.TwoDDoc{
+			Header:    header,
+			Message:   message,
+			Signature: signature,
+		},
+	}, nil
+}
+
+func decodeHeader(input string) (header *types.TwoDDocHeader, remaining string, err error) {
+	length := 22
+	version, err := strconv.Atoi(utils.Substring(input, 2, 4))
+	if err != nil {
+		return nil, "", err
+	}
+
+	header = &types.TwoDDocHeader{
+		IDFlag:         utils.Substring(input, 0, 2),
+		Version:        version,
+		Issuer:         utils.Substring(input, 4, 8),
+		CertID:         utils.Substring(input, 8, 12),
+		DocumentDate:   utils.Substring(input, 12, 16),
+		SignatureDate:  utils.Substring(input, 16, 20),
+		DocumentTypeID: utils.Substring(input, 20, 22),
+	}
+
+	switch version {
+	case 3:
+		header.PerimeterID = utils.Substring(input, 22, 24)
+		length = 24
+	case 4:
+		header.PerimeterID = utils.Substring(input, 22, 24)
+		header.CountryID = utils.Substring(input, 24, 26)
+		length = 26
+	}
+
+	return header, utils.Substring(input, length, len(input)), err
+}
+
+func decodeData(input string) (message *types.TwoDDocMessage, signature string, err error) {
+	data := make(map[string]interface{})
+
+	units := strings.Split(input, string(rune(31)))
+	groups := strings.Split(units[0], string(rune(29)))
+	signature = units[1]
+
+	for _, group := range groups {
+		key, value := decodeField(group)
+		data[key] = value
+	}
+
+	jsonString, err := json.Marshal(data)
+	err = json.Unmarshal(jsonString, &message)
+
+	return
+}
+
+func decodeField(input string) (key string, value string) {
+	key = utils.Substring(input, 0, 2)
+	value = utils.Substring(input, 2, len(input))
+	return
+}

decoders/dcc.go

@@ -0,0 +1,40 @@
+package decoders
+
+import (
+	"github.com/alexpresso/gocovidcertificate/types"
+	"github.com/alexpresso/gocovidcertificate/utils"
+	"strings"
+)
+
+var DCCPrefixes = map[string]bool{"HC1": true, "LT1": true}
+
+func dccDecode(input string) (*types.Certificate, error) {
+	var err error
+	var bytes []byte
+
+	for prefix := range DCCPrefixes {
+		input = strings.TrimPrefix(input, prefix+":")
+	}
+
+	bytes, err = utils.Base45decode(input)
+	if err != nil {
+		return nil, err
+	}
+
+	if bytes[0] == 0x78 {
+		bytes, err = utils.ZlibDecompress(bytes)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	cose, err := utils.DecodeCOSE(bytes)
+	if err != nil {
+		return nil, err
+	}
+
+	return &types.Certificate{
+		Type: types.DCC,
+		Data: cose,
+	}, nil
+}

decoders/decoder.go

@@ -0,0 +1,17 @@
+package decoders
+
+import (
+	"errors"
+	"github.com/alexpresso/gocovidcertificate/types"
+	"strings"
+)
+
+func Decode(input string) (*types.Certificate, error) {
+	if split := strings.Split(input, ":")[0]; DCCPrefixes[split] {
+		return dccDecode(input)
+	} else if strings.HasPrefix(input, TwoDPrefix) {
+		return twoDDocDecode(input)
+	}
+
+	return nil, errors.New("unsupported code format")
+}

gocovidcertificate.go

@@ -4,16 +4,15 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"github.com/alexpresso/gocovidcertificate/dcc"
+	"github.com/alexpresso/gocovidcertificate/decoders"
 	"log"
 )
 
-
 func main() {
 	var (
-		err error
+		err       error
 		mustPrint = flag.Bool("print", true, "Prints content of the decoded certificate")
-		code = flag.String("code", "", "The DCC code you want to process")
+		code      = flag.String("code", "", "The DCC code you want to process")
 	)
 
 	flag.Parse()
@@ -22,13 +21,13 @@ func main() {
 		log.Fatal("Missing -code flag")
 	}
 
-	cose, err := dcc.Decode(*code)
+	data, err := decoders.Decode(*code)
 	if err != nil {
 		log.Fatal(err)
 	}
 
 	if *mustPrint {
-		indent, err := json.MarshalIndent(cose, "", "   ")
+		indent, err := json.MarshalIndent(data, "", "   ")
 		if err != nil {
 			log.Fatal(err)
 		}

types/2dcertificate.go

@@ -0,0 +1,32 @@
+package types
+
+type TwoDDoc struct {
+	Header    *TwoDDocHeader
+	Message   *TwoDDocMessage
+	Signature string
+}
+
+type TwoDDocHeader struct {
+	IDFlag         string
+	Version        int
+	Issuer         string
+	CertID         string
+	DocumentDate   string
+	SignatureDate  string
+	DocumentTypeID string
+	PerimeterID    string
+	CountryID      string
+}
+
+type TwoDDocMessage struct {
+	Lastname          string `json:"L0"`
+	Firstname         string `json:"L1"`
+	DateOfBirth       string `json:"L2"`
+	TargetedAgent     string `json:"L3"`
+	VaccineATC        string `json:"L4"`
+	Dose1Manufacturer string `json:"L5"`
+	Dose2Manufacturer string `json:"L6"`
+	Dose              int    `json:"L7,string"`
+	RequiredDoses     int    `json:"L8,string"`
+	Date              int    `json:"L9,string"`
+}

types/certificate.go

@@ -1,57 +1,13 @@
 package types
 
-// DccRoot see https://github.com/ehn-dcc-development/ehn-dcc-schema
-type DccRoot struct {
-	DCC covidCertificate `cbor:"1,keyasint"`
-}
-
-type covidCertificate struct {
-	Version		string		`cbor:"ver" json:"version"`
-	DateOfBirth	string		`cbor:"dob" json:"dateOfBirth"`
-	Name		name		`cbor:"nam" json:"name"`
-	Vaccines	[]vaccineEntry	`cbor:"v" json:"vaccines"`
-	Tests		[]testEntry 	`cbor:"t" json:"tests"`
-	Recoveries	[]recoveryEntry	`cbor:"r" json:"recoveries"`
-}
-
-type name struct {
-	Surname		string	`cbor:"fn" json:"surname"`
-	StdSurname	string	`cbor:"fnt" json:"stdSurname"`
-	Forename	string	`cbor:"gn" json:"forename"`
-	StdForename	string	`cbor:"gnt" json:"stdForename"`
-}
-
-type vaccineEntry struct {
-	TargetedAgent	string	`cbor:"tg" json:"targetedAgent"`
-	Vaccine		string  `cbor:"vp" json:"vaccine"`
-	Product		string  `cbor:"mp" json:"product"`
-	Manufacturer	string  `cbor:"ma" json:"manufacturer"`
-	Dose		int64	`cbor:"dn" json:"doseNumber"`
-	DoseSeries	int64	`cbor:"sd" json:"doseSeries"`
-	Date		string	`cbor:"dt" json:"date"`
-	Country		string	`cbor:"co" json:"country"`
-	Issuer		string	`cbor:"is" json:"issuer"`
-	CertificateID	string	`cbor:"ci" json:"certificateID"`
-}
+const (
+	DCC     CertificateType = "DCC"
+	TWODDOC CertificateType = "2DDOC"
+)
 
-type testEntry struct {
-	TargetedAgent	string	`cbor:"tg" json:"targetedAgent"`
-	TestType 	string	`cbor:"tt" json:"testType"`
-	Name 		string	`cbor:"nm" json:"name"`
-	Manufacturer   	string	`cbor:"ma" json:"manufacturer"`
-	SampleDatetime 	string	`cbor:"sc" json:"sampleDatetime"`
-	TestResult     	string	`cbor:"tr" json:"testResult"`
-	TestingCentre  	string	`cbor:"tc" json:"testingCentre"`
-	Country       	string	`cbor:"co" json:"country"`
-	Issuer        	string	`cbor:"is" json:"issuer"`
-	CertificateID 	string	`cbor:"ci" json:"certificateID"`
-}
+type CertificateType string
 
-type recoveryEntry struct {
-	TargetedAgent	string	`cbor:"tg" json:"targetedAgent"`
-	Country 	string	`cbor:"co" json:"country"`
-	Issuer 		string	`cbor:"is" json:"issuer"`
-	ValidFrom	string	`cbor:"df" json:"validFrom"`
-	ValidUntil	string	`cbor:"du" json:"validUntil"`
-	CertificateID 	string	`cbor:"ci" json:"certificateID"`
+type Certificate struct {
+	Type CertificateType
+	Data interface{}
 }

types/cose.go

@@ -2,35 +2,35 @@ package types
 
 // Signed see https://datatracker.ietf.org/doc/html/rfc8152#section-2
 type Signed struct {
-	_		struct{} `cbor:",toarray"`
-	Protected	[]byte
-	Unprotected	map[interface{}]interface{}
-	Content		[]byte
-	Signature	[]byte
+	_           struct{} `cbor:",toarray"`
+	Protected   []byte
+	Unprotected map[interface{}]interface{}
+	Content     []byte
+	Signature   []byte
 }
 
 // Header see https://datatracker.ietf.org/doc/html/rfc8152#section-3.1 & https://www.iana.org/assignments/cose/cose.xhtml
 type Header struct {
-	Alg		int 	`cbor:"1,keyasint,omitempty"`
-	Kid		[]byte 	`cbor:"4,keyasint,omitempty"`
-	IV		[]byte	`cbor:"5,keyasint,omitempty"`
+	Alg int    `cbor:"1,keyasint,omitempty"`
+	Kid []byte `cbor:"4,keyasint,omitempty"`
+	IV  []byte `cbor:"5,keyasint,omitempty"`
 }
 
 // Claims see https://datatracker.ietf.org/doc/html/draft-ietf-ace-cbor-web-token-08#section-3.1
 type Claims struct {
-	Iss		string	`cbor:"1,keyasint"`
-	Sub		string	`cbor:"2,keyasint"`
-	Aud		string	`cbor:"3,keyasint"`
-	Exp		int64	`cbor:"4,keyasint"`
-	Nbf		int	`cbor:"5,keyasint"`
-	Iat		int64	`cbor:"6,keyasint"`
-	Cti		[]byte  `cbor:"7,keyasint"`
-	HCData		DccRoot `cbor:"-260,keyasint"`
-	LCData		DccRoot `cbor:"-250,keyasint"`
+	Iss    string  `cbor:"1,keyasint"`
+	Sub    string  `cbor:"2,keyasint"`
+	Aud    string  `cbor:"3,keyasint"`
+	Exp    int64   `cbor:"4,keyasint"`
+	Nbf    int     `cbor:"5,keyasint"`
+	Iat    int64   `cbor:"6,keyasint"`
+	Cti    []byte  `cbor:"7,keyasint"`
+	HCData DccRoot `cbor:"-260,keyasint"`
+	LCData DccRoot `cbor:"-250,keyasint"`
 }
 
 type COSE struct {
-	Signed	Signed `json:"-"`
-	Header	Header
-	Claims	Claims
+	Signed Signed `json:"-"`
+	Header Header
+	Claims Claims
 }