| 47 | } |
| 48 | |
| 49 | func NewHash(cfg baker.FilterParams) (baker.Filter, error) { |
| 50 | dcfg := cfg.DecodedConfig.(*HashConfig) |
| 51 | |
| 52 | src, ok := cfg.FieldByName(dcfg.SrcField) |
| 53 | if !ok { |
| 54 | return nil, fmt.Errorf("can't find the SrcField %s", dcfg.SrcField) |
| 55 | } |
| 56 | |
| 57 | dst, ok := cfg.FieldByName(dcfg.DstField) |
| 58 | if !ok { |
| 59 | return nil, fmt.Errorf("can't find the DstField %s", dcfg.DstField) |
| 60 | } |
| 61 | |
| 62 | h := &Hash{ |
| 63 | src: src, |
| 64 | dst: dst, |
| 65 | } |
| 66 | |
| 67 | switch dcfg.Function { |
| 68 | case "md5": |
| 69 | h.hash = func(b []byte) ([]byte, error) { |
| 70 | sum := md5.Sum(b) |
| 71 | return sum[:], nil |
| 72 | } |
| 73 | case "sha256": |
| 74 | h.hash = func(b []byte) ([]byte, error) { |
| 75 | sum := sha256.Sum256(b) |
| 76 | return sum[:], nil |
| 77 | } |
| 78 | default: |
| 79 | return nil, fmt.Errorf("unsupported hash function %s", dcfg.Function) |
| 80 | } |
| 81 | |
| 82 | switch dcfg.Encoding { |
| 83 | case "hex": |
| 84 | h.encode = func(b []byte) ([]byte, error) { |
| 85 | dst := make([]byte, hex.EncodedLen(len(b))) |
| 86 | hex.Encode(dst, b) |
| 87 | return dst, nil |
| 88 | } |
| 89 | case "": // pass through |
| 90 | h.encode = func(b []byte) ([]byte, error) { return b, nil } |
| 91 | default: |
| 92 | return nil, fmt.Errorf("unsupported encoding %s", dcfg.Encoding) |
| 93 | } |
| 94 | |
| 95 | return h, nil |
| 96 | } |
| 97 | |
| 98 | func (h *Hash) Stats() baker.FilterStats { |
| 99 | return baker.FilterStats{ |