Add 2fa for authentification (#383)

Fix user tests

Add swagger docs

Fix lint

Add totp check when logging in

Make totp enrollment work

Add migration for totp table

go mod vendor

Add routes for totp routes

Add route handler for totp routes

Add basic implementation to enroll a user in totp

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/383

vendor/github.com/boombuler/barcode/qr/alphanumeric.go

@@ -0,0 +1,66 @@
+package qr
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/boombuler/barcode/utils"
+)
+
+const charSet string = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:"
+
+func stringToAlphaIdx(content string) <-chan int {
+	result := make(chan int)
+	go func() {
+		for _, r := range content {
+			idx := strings.IndexRune(charSet, r)
+			result <- idx
+			if idx < 0 {
+				break
+			}
+		}
+		close(result)
+	}()
+
+	return result
+}
+
+func encodeAlphaNumeric(content string, ecl ErrorCorrectionLevel) (*utils.BitList, *versionInfo, error) {
+
+	contentLenIsOdd := len(content)%2 == 1
+	contentBitCount := (len(content) / 2) * 11
+	if contentLenIsOdd {
+		contentBitCount += 6
+	}
+	vi := findSmallestVersionInfo(ecl, alphaNumericMode, contentBitCount)
+	if vi == nil {
+		return nil, nil, errors.New("To much data to encode")
+	}
+
+	res := new(utils.BitList)
+	res.AddBits(int(alphaNumericMode), 4)
+	res.AddBits(len(content), vi.charCountBits(alphaNumericMode))
+
+	encoder := stringToAlphaIdx(content)
+
+	for idx := 0; idx < len(content)/2; idx++ {
+		c1 := <-encoder
+		c2 := <-encoder
+		if c1 < 0 || c2 < 0 {
+			return nil, nil, fmt.Errorf("\"%s\" can not be encoded as %s", content, AlphaNumeric)
+		}
+		res.AddBits(c1*45+c2, 11)
+	}
+	if contentLenIsOdd {
+		c := <-encoder
+		if c < 0 {
+			return nil, nil, fmt.Errorf("\"%s\" can not be encoded as %s", content, AlphaNumeric)
+		}
+		res.AddBits(c, 6)
+	}
+
+	addPaddingAndTerminator(res, vi)
+
+	return res, vi, nil
+}