61 lines
1.2 KiB
Go
61 lines
1.2 KiB
Go
package sec
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import (
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"crypto/rsa"
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"crypto/x509"
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"encoding/pem"
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"fmt"
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"github.com/golang-jwt/jwt/v5"
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"os"
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)
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type JwtReader struct {
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key *rsa.PublicKey
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}
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func NewJwtReader(fp string) (*JwtReader, error) {
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rawKey, err := os.ReadFile(fp)
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if err != nil {
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return nil, err
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}
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block, _ := pem.Decode(rawKey)
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if block == nil || block.Type != "PUBLIC KEY" {
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return nil, fmt.Errorf("failed to decode PEM block containing private key")
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}
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anyPk, err := x509.ParsePKIXPublicKey(block.Bytes)
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if err != nil {
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return nil, err
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}
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pk, ok := anyPk.(*rsa.PublicKey)
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if !ok {
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return nil, fmt.Errorf("not an RSA public key")
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}
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return &JwtReader{
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key: pk,
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}, nil
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}
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func ReadJwt[T jwt.Claims](v *JwtReader, in string, out T) (T, error) {
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token, err := jwt.ParseWithClaims(in, out, func(token *jwt.Token) (interface{}, error) {
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if _, ok := token.Method.(*jwt.SigningMethodRSA); !ok {
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return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
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}
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return v.key, nil
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})
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if err != nil {
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return out, err
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} else if !token.Valid {
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return out, fmt.Errorf("token is not valid")
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}
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if claims, ok := token.Claims.(T); ok {
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return claims, nil
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} else {
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return out, err
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}
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}
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