diff options
Diffstat (limited to 'vendor/github.com/hashicorp/vault/helper')
-rw-r--r-- | vendor/github.com/hashicorp/vault/helper/compressutil/compress.go | 159 | ||||
-rw-r--r-- | vendor/github.com/hashicorp/vault/helper/jsonutil/json.go | 99 |
2 files changed, 258 insertions, 0 deletions
diff --git a/vendor/github.com/hashicorp/vault/helper/compressutil/compress.go b/vendor/github.com/hashicorp/vault/helper/compressutil/compress.go new file mode 100644 index 0000000..e485f2f --- /dev/null +++ b/vendor/github.com/hashicorp/vault/helper/compressutil/compress.go @@ -0,0 +1,159 @@ +package compressutil + +import ( + "bytes" + "compress/gzip" + "compress/lzw" + "fmt" + "io" +) + +const ( + // A byte value used as a canary prefix for the compressed information + // which is used to distinguish if a JSON input is compressed or not. + // The value of this constant should not be a first character of any + // valid JSON string. + + // Byte value used as canary when using Gzip format + CompressionCanaryGzip byte = 'G' + + // Byte value used as canary when using Lzw format + CompressionCanaryLzw byte = 'L' + + CompressionTypeLzw = "lzw" + + CompressionTypeGzip = "gzip" +) + +// CompressionConfig is used to select a compression type to be performed by +// Compress and Decompress utilities. +// Supported types are: +// * CompressionTypeLzw +// * CompressionTypeGzip +// +// When using CompressionTypeGzip, the compression levels can also be chosen: +// * gzip.DefaultCompression +// * gzip.BestSpeed +// * gzip.BestCompression +type CompressionConfig struct { + // Type of the compression algorithm to be used + Type string + + // When using Gzip format, the compression level to employ + GzipCompressionLevel int +} + +// Compress places the canary byte in a buffer and uses the same buffer to fill +// in the compressed information of the given input. The configuration supports +// two type of compression: LZW and Gzip. When using Gzip compression format, +// if GzipCompressionLevel is not specified, the 'gzip.DefaultCompression' will +// be assumed. +func Compress(data []byte, config *CompressionConfig) ([]byte, error) { + var buf bytes.Buffer + var writer io.WriteCloser + var err error + + if config == nil { + return nil, fmt.Errorf("config is nil") + } + + // Write the canary into the buffer and create writer to compress the + // input data based on the configured type + switch config.Type { + case CompressionTypeLzw: + buf.Write([]byte{CompressionCanaryLzw}) + + writer = lzw.NewWriter(&buf, lzw.LSB, 8) + case CompressionTypeGzip: + buf.Write([]byte{CompressionCanaryGzip}) + + switch { + case config.GzipCompressionLevel == gzip.BestCompression, + config.GzipCompressionLevel == gzip.BestSpeed, + config.GzipCompressionLevel == gzip.DefaultCompression: + // These are valid compression levels + default: + // If compression level is set to NoCompression or to + // any invalid value, fallback to Defaultcompression + config.GzipCompressionLevel = gzip.DefaultCompression + } + writer, err = gzip.NewWriterLevel(&buf, config.GzipCompressionLevel) + default: + return nil, fmt.Errorf("unsupported compression type") + } + if err != nil { + return nil, fmt.Errorf("failed to create a compression writer; err: %v", err) + } + + if writer == nil { + return nil, fmt.Errorf("failed to create a compression writer") + } + + // Compress the input and place it in the same buffer containing the + // canary byte. + if _, err = writer.Write(data); err != nil { + return nil, fmt.Errorf("failed to compress input data; err: %v", err) + } + + // Close the io.WriteCloser + if err = writer.Close(); err != nil { + return nil, err + } + + // Return the compressed bytes with canary byte at the start + return buf.Bytes(), nil +} + +// Decompress checks if the first byte in the input matches the canary byte. +// If the first byte is a canary byte, then the input past the canary byte +// will be decompressed using the method specified in the given configuration. +// If the first byte isn't a canary byte, then the utility returns a boolean +// value indicating that the input was not compressed. +func Decompress(data []byte) ([]byte, bool, error) { + var err error + var reader io.ReadCloser + if data == nil || len(data) == 0 { + return nil, false, fmt.Errorf("'data' being decompressed is empty") + } + + switch { + case data[0] == CompressionCanaryGzip: + // If the first byte matches the canary byte, remove the canary + // byte and try to decompress the data that is after the canary. + if len(data) < 2 { + return nil, false, fmt.Errorf("invalid 'data' after the canary") + } + data = data[1:] + reader, err = gzip.NewReader(bytes.NewReader(data)) + case data[0] == CompressionCanaryLzw: + // If the first byte matches the canary byte, remove the canary + // byte and try to decompress the data that is after the canary. + if len(data) < 2 { + return nil, false, fmt.Errorf("invalid 'data' after the canary") + } + data = data[1:] + reader = lzw.NewReader(bytes.NewReader(data), lzw.LSB, 8) + default: + // If the first byte doesn't match the canary byte, it means + // that the content was not compressed at all. Indicate the + // caller that the input was not compressed. + return nil, true, nil + } + if err != nil { + return nil, false, fmt.Errorf("failed to create a compression reader; err: %v", err) + } + if reader == nil { + return nil, false, fmt.Errorf("failed to create a compression reader") + } + + // Close the io.ReadCloser + defer reader.Close() + + // Read all the compressed data into a buffer + var buf bytes.Buffer + if _, err = io.Copy(&buf, reader); err != nil { + return nil, false, err + } + + return buf.Bytes(), false, nil +} diff --git a/vendor/github.com/hashicorp/vault/helper/jsonutil/json.go b/vendor/github.com/hashicorp/vault/helper/jsonutil/json.go new file mode 100644 index 0000000..a96745b --- /dev/null +++ b/vendor/github.com/hashicorp/vault/helper/jsonutil/json.go @@ -0,0 +1,99 @@ +package jsonutil + +import ( + "bytes" + "compress/gzip" + "encoding/json" + "fmt" + "io" + + "github.com/hashicorp/vault/helper/compressutil" +) + +// Encodes/Marshals the given object into JSON +func EncodeJSON(in interface{}) ([]byte, error) { + if in == nil { + return nil, fmt.Errorf("input for encoding is nil") + } + var buf bytes.Buffer + enc := json.NewEncoder(&buf) + if err := enc.Encode(in); err != nil { + return nil, err + } + return buf.Bytes(), nil +} + +// EncodeJSONAndCompress encodes the given input into JSON and compresses the +// encoded value (using Gzip format BestCompression level, by default). A +// canary byte is placed at the beginning of the returned bytes for the logic +// in decompression method to identify compressed input. +func EncodeJSONAndCompress(in interface{}, config *compressutil.CompressionConfig) ([]byte, error) { + if in == nil { + return nil, fmt.Errorf("input for encoding is nil") + } + + // First JSON encode the given input + encodedBytes, err := EncodeJSON(in) + if err != nil { + return nil, err + } + + if config == nil { + config = &compressutil.CompressionConfig{ + Type: compressutil.CompressionTypeGzip, + GzipCompressionLevel: gzip.BestCompression, + } + } + + return compressutil.Compress(encodedBytes, config) +} + +// DecodeJSON tries to decompress the given data. The call to decompress, fails +// if the content was not compressed in the first place, which is identified by +// a canary byte before the compressed data. If the data is not compressed, it +// is JSON decoded directly. Otherwise the decompressed data will be JSON +// decoded. +func DecodeJSON(data []byte, out interface{}) error { + if data == nil || len(data) == 0 { + return fmt.Errorf("'data' being decoded is nil") + } + if out == nil { + return fmt.Errorf("output parameter 'out' is nil") + } + + // Decompress the data if it was compressed in the first place + decompressedBytes, uncompressed, err := compressutil.Decompress(data) + if err != nil { + return fmt.Errorf("failed to decompress JSON: err: %v", err) + } + if !uncompressed && (decompressedBytes == nil || len(decompressedBytes) == 0) { + return fmt.Errorf("decompressed data being decoded is invalid") + } + + // If the input supplied failed to contain the compression canary, it + // will be notified by the compression utility. Decode the decompressed + // input. + if !uncompressed { + data = decompressedBytes + } + + return DecodeJSONFromReader(bytes.NewReader(data), out) +} + +// Decodes/Unmarshals the given io.Reader pointing to a JSON, into a desired object +func DecodeJSONFromReader(r io.Reader, out interface{}) error { + if r == nil { + return fmt.Errorf("'io.Reader' being decoded is nil") + } + if out == nil { + return fmt.Errorf("output parameter 'out' is nil") + } + + dec := json.NewDecoder(r) + + // While decoding JSON values, intepret the integer values as `json.Number`s instead of `float64`. + dec.UseNumber() + + // Since 'out' is an interface representing a pointer, pass it to the decoder without an '&' + return dec.Decode(out) +} |