added (un)marshal methods

1 files changed, 413 insertions, 0 deletions

diff --git a/types/ascii.go b/types/ascii.go
new file mode 100644
index 0000000..88b372e
--- /dev/null
+++ b/types/ascii.go
@@ -0,0 +1,413 @@
+package types
+
+import (
+	"bytes"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"strconv"
+)
+
+const (
+	// Delim is a key-value separator
+	Delim = "="
+
+	// EOL is a line sepator
+	EOL = "\n"
+
+	// NumField* is the number of unique keys in an incoming ASCII message
+	NumFieldLeaf                    = 4
+	NumFieldSignedTreeHead          = 5
+	NumFieldConsistencyProof        = 3
+	NumFieldInclusionProof          = 3
+	NumFieldLeavesRequest           = 2
+	NumFieldInclusionProofRequest   = 2
+	NumFieldConsistencyProofRequest = 2
+	NumFieldLeafRequest             = 5
+	NumFieldCosignatureRequest      = 2
+
+	// New leaf keys
+	ShardHint            = "shard_hint"
+	Checksum             = "checksum"
+	SignatureOverMessage = "signature_over_message"
+	VerificationKey      = "verification_key"
+	DomainHint           = "domain_hint"
+
+	// Inclusion proof keys
+	LeafHash      = "leaf_hash"
+	LeafIndex     = "leaf_index"
+	InclusionPath = "inclusion_path"
+
+	// Consistency proof keys
+	NewSize         = "new_size"
+	OldSize         = "old_size"
+	ConsistencyPath = "consistency_path"
+
+	// Range of leaves keys
+	StartSize = "start_size"
+	EndSize   = "end_size"
+
+	// Tree head keys
+	Timestamp = "timestamp"
+	TreeSize  = "tree_size"
+	RootHash  = "root_hash"
+
+	// Signature and signer-identity keys
+	Signature = "signature"
+	KeyHash   = "key_hash"
+)
+
+// MessageASCI is a wrapper that manages ASCII key-value pairs
+type MessageASCII struct {
+	m map[string][]string
+}
+
+// NewMessageASCII unpacks an incoming ASCII message
+func NewMessageASCII(r io.Reader, numFieldExpected int) (*MessageASCII, error) {
+	buf, err := io.ReadAll(r)
+	if err != nil {
+		return nil, fmt.Errorf("ReadAll: %v", err)
+	}
+	lines := bytes.Split(buf, []byte(EOL))
+	if len(lines) <= 1 {
+		return nil, fmt.Errorf("Not enough lines: empty")
+	}
+	lines = lines[:len(lines)-1] // valid message => split gives empty last line
+
+	msg := MessageASCII{make(map[string][]string)}
+	for _, line := range lines {
+		split := bytes.Index(line, []byte(Delim))
+		if split == -1 {
+			return nil, fmt.Errorf("invalid line: %v", string(line))
+		}
+
+		key := string(line[:split])
+		value := string(line[split+len(Delim):])
+		values, ok := msg.m[key]
+		if !ok {
+			values = nil
+			msg.m[key] = values
+		}
+		msg.m[key] = append(values, value)
+	}
+
+	if msg.NumField() != numFieldExpected {
+		return nil, fmt.Errorf("Unexpected number of keys: %v", msg.NumField())
+	}
+	return &msg, nil
+}
+
+// NumField returns the number of unique keys
+func (msg *MessageASCII) NumField() int {
+	return len(msg.m)
+}
+
+// GetStrings returns a list of strings
+func (msg *MessageASCII) GetStrings(key string) []string {
+	strs, ok := msg.m[key]
+	if !ok {
+		return nil
+	}
+	return strs
+}
+
+// GetString unpacks a string
+func (msg *MessageASCII) GetString(key string) (string, error) {
+	strs := msg.GetStrings(key)
+	if len(strs) != 1 {
+		return "", fmt.Errorf("expected one string: %v", strs)
+	}
+	return strs[0], nil
+}
+
+// GetUint64 unpacks an uint64
+func (msg *MessageASCII) GetUint64(key string) (uint64, error) {
+	str, err := msg.GetString(key)
+	if err != nil {
+		return 0, fmt.Errorf("GetString: %v", err)
+	}
+	num, err := strconv.ParseUint(str, 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("ParseUint: %v", err)
+	}
+	return num, nil
+}
+
+// GetHash unpacks a hash
+func (msg *MessageASCII) GetHash(key string) (*[HashSize]byte, error) {
+	str, err := msg.GetString(key)
+	if err != nil {
+		return nil, fmt.Errorf("GetString: %v", err)
+	}
+
+	var hash [HashSize]byte
+	if err := decodeHex(str, hash[:]); err != nil {
+		return nil, fmt.Errorf("decodeHex: %v", err)
+	}
+	return &hash, nil
+}
+
+// GetSignature unpacks a signature
+func (msg *MessageASCII) GetSignature(key string) (*[SignatureSize]byte, error) {
+	str, err := msg.GetString(key)
+	if err != nil {
+		return nil, fmt.Errorf("GetString: %v", err)
+	}
+
+	var signature [SignatureSize]byte
+	if err := decodeHex(str, signature[:]); err != nil {
+		return nil, fmt.Errorf("decodeHex: %v", err)
+	}
+	return &signature, nil
+}
+
+// GetVerificationKey unpacks a verification key
+func (msg *MessageASCII) GetVerificationKey(key string) (*[VerificationKeySize]byte, error) {
+	str, err := msg.GetString(key)
+	if err != nil {
+		return nil, fmt.Errorf("GetString: %v", err)
+	}
+
+	var vk [VerificationKeySize]byte
+	if err := decodeHex(str, vk[:]); err != nil {
+		return nil, fmt.Errorf("decodeHex: %v", err)
+	}
+	return &vk, nil
+}
+
+// decodeHex decodes a hex-encoded string into an already-sized byte slice
+func decodeHex(str string, out []byte) error {
+	buf, err := hex.DecodeString(str)
+	if err != nil {
+		return fmt.Errorf("DecodeString: %v", err)
+	}
+	if len(buf) != len(out) {
+		return fmt.Errorf("invalid length: %v", len(buf))
+	}
+	copy(out, buf)
+	return nil
+}
+
+/*
+ *
+ * MarshalASCII wrappers for types that the log server outputs
+ *
+ */
+func (l *Leaf) MarshalASCII(w io.Writer) error {
+	if err := writeASCII(w, ShardHint, strconv.FormatUint(l.ShardHint, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, Checksum, hex.EncodeToString(l.Checksum[:])); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, Signature, hex.EncodeToString(l.Signature[:])); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, KeyHash, hex.EncodeToString(l.KeyHash[:])); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	return nil
+}
+
+func (sth *SignedTreeHead) MarshalASCII(w io.Writer) error {
+	if err := writeASCII(w, Timestamp, strconv.FormatUint(sth.Timestamp, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, TreeSize, strconv.FormatUint(sth.TreeSize, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, RootHash, hex.EncodeToString(sth.RootHash[:])); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	for _, sigident := range sth.SigIdent {
+		if err := writeASCII(w, Signature, hex.EncodeToString(sigident.Signature[:])); err != nil {
+			return fmt.Errorf("writeASCII: %v", err)
+		}
+		if err := writeASCII(w, KeyHash, hex.EncodeToString(sigident.KeyHash[:])); err != nil {
+			return fmt.Errorf("writeASCII: %v", err)
+		}
+	}
+	return nil
+}
+
+func (p *ConsistencyProof) MarshalASCII(w io.Writer) error {
+	if err := writeASCII(w, NewSize, strconv.FormatUint(p.NewSize, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, OldSize, strconv.FormatUint(p.OldSize, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	for _, hash := range p.Path {
+		if err := writeASCII(w, ConsistencyPath, hex.EncodeToString(hash[:])); err != nil {
+			return fmt.Errorf("writeASCII: %v", err)
+		}
+	}
+	return nil
+}
+
+func (p *InclusionProof) MarshalASCII(w io.Writer) error {
+	if err := writeASCII(w, TreeSize, strconv.FormatUint(p.TreeSize, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	if err := writeASCII(w, LeafIndex, strconv.FormatUint(p.LeafIndex, 10)); err != nil {
+		return fmt.Errorf("writeASCII: %v", err)
+	}
+	for _, hash := range p.Path {
+		if err := writeASCII(w, InclusionPath, hex.EncodeToString(hash[:])); err != nil {
+			return fmt.Errorf("writeASCII: %v", err)
+		}
+	}
+	return nil
+}
+
+func writeASCII(w io.Writer, key, value string) error {
+	if _, err := fmt.Fprintf(w, "%s%s%s%s", key, Delim, value, EOL); err != nil {
+		return fmt.Errorf("Fprintf: %v", err)
+	}
+	return nil
+}
+
+/*
+ *
+ * Unmarshal ASCII wrappers that the log server and/or log clients receive.
+ *
+ */
+func (ll *LeafList) UnmarshalASCII(r io.Reader) error {
+	return nil
+}
+
+func (sth *SignedTreeHead) UnmarshalASCII(r io.Reader) error {
+	msg, err := NewMessageASCII(r, NumFieldSignedTreeHead)
+	if err != nil {
+		return fmt.Errorf("NewMessageASCII: %v", err)
+	}
+
+	// TreeHead
+	if sth.Timestamp, err = msg.GetUint64(Timestamp); err != nil {
+		return fmt.Errorf("GetUint64(Timestamp): %v", err)
+	}
+	if sth.TreeSize, err = msg.GetUint64(TreeSize); err != nil {
+		return fmt.Errorf("GetUint64(TreeSize): %v", err)
+	}
+	if sth.RootHash, err = msg.GetHash(RootHash); err != nil {
+		return fmt.Errorf("GetHash(RootHash): %v", err)
+	}
+
+	// SigIdent
+	signatures := msg.GetStrings(Signature)
+	if len(signatures) == 0 {
+		return fmt.Errorf("no signer")
+	}
+	keyHashes := msg.GetStrings(KeyHash)
+	if len(signatures) != len(keyHashes) {
+		return fmt.Errorf("mismatched signature-signer count")
+	}
+	sth.SigIdent = make([]*SigIdent, 0, len(signatures))
+	for i, n := 0, len(signatures); i < n; i++ {
+		var signature [SignatureSize]byte
+		if err := decodeHex(signatures[i], signature[:]); err != nil {
+			return fmt.Errorf("decodeHex: %v", err)
+		}
+		var hash [HashSize]byte
+		if err := decodeHex(keyHashes[i], hash[:]); err != nil {
+			return fmt.Errorf("decodeHex: %v", err)
+		}
+		sth.SigIdent = append(sth.SigIdent, &SigIdent{
+			Signature: &signature,
+			KeyHash:   &hash,
+		})
+	}
+	return nil
+}
+
+func (p *InclusionProof) UnmarshalASCII(r io.Reader) error {
+	return nil
+}
+
+func (p *ConsistencyProof) UnmarshalASCII(r io.Reader) error {
+	return nil
+}
+
+func (req *InclusionProofRequest) UnmarshalASCII(r io.Reader) error {
+	msg, err := NewMessageASCII(r, NumFieldInclusionProofRequest)
+	if err != nil {
+		return fmt.Errorf("NewMessageASCII: %v", err)
+	}
+
+	if req.LeafHash, err = msg.GetHash(LeafHash); err != nil {
+		return fmt.Errorf("GetHash(LeafHash): %v", err)
+	}
+	if req.TreeSize, err = msg.GetUint64(TreeSize); err != nil {
+		return fmt.Errorf("GetUint64(TreeSize): %v", err)
+	}
+	return nil
+}
+
+func (req *ConsistencyProofRequest) UnmarshalASCII(r io.Reader) error {
+	msg, err := NewMessageASCII(r, NumFieldConsistencyProofRequest)
+	if err != nil {
+		return fmt.Errorf("NewMessageASCII: %v", err)
+	}
+
+	if req.NewSize, err = msg.GetUint64(NewSize); err != nil {
+		return fmt.Errorf("GetUint64(NewSize): %v", err)
+	}
+	if req.OldSize, err = msg.GetUint64(OldSize); err != nil {
+		return fmt.Errorf("GetUint64(OldSize): %v", err)
+	}
+	return nil
+}
+
+func (req *LeavesRequest) UnmarshalASCII(r io.Reader) error {
+	msg, err := NewMessageASCII(r, NumFieldLeavesRequest)
+	if err != nil {
+		return fmt.Errorf("NewMessageASCII: %v", err)
+	}
+
+	if req.StartSize, err = msg.GetUint64(StartSize); err != nil {
+		return fmt.Errorf("GetUint64(StartSize): %v", err)
+	}
+	if req.EndSize, err = msg.GetUint64(EndSize); err != nil {
+		return fmt.Errorf("GetUint64(EndSize): %v", err)
+	}
+	return nil
+}
+
+func (req *LeafRequest) UnmarshalASCII(r io.Reader) error {
+	msg, err := NewMessageASCII(r, NumFieldLeafRequest)
+	if err != nil {
+		return fmt.Errorf("NewMessageASCII: %v", err)
+	}
+
+	if req.ShardHint, err = msg.GetUint64(ShardHint); err != nil {
+		return fmt.Errorf("GetUint64(ShardHint): %v", err)
+	}
+	if req.Checksum, err = msg.GetHash(Checksum); err != nil {
+		return fmt.Errorf("GetHash(Checksum): %v", err)
+	}
+	if req.Signature, err = msg.GetSignature(Signature); err != nil {
+		return fmt.Errorf("GetSignature: %v", err)
+	}
+	if req.VerificationKey, err = msg.GetVerificationKey(VerificationKey); err != nil {
+		return fmt.Errorf("GetVerificationKey: %v", err)
+	}
+	if req.DomainHint, err = msg.GetString(DomainHint); err != nil {
+		return fmt.Errorf("GetString(DomainHint): %v", err)
+	}
+	return nil
+}
+
+func (req *CosignatureRequest) UnmarshalASCII(r io.Reader) error {
+	msg, err := NewMessageASCII(r, NumFieldCosignatureRequest)
+	if err != nil {
+		return fmt.Errorf("NewMessageASCII: %v", err)
+	}
+
+	if req.Signature, err = msg.GetSignature(Signature); err != nil {
+		return fmt.Errorf("GetSignature: %v", err)
+	}
+	if req.KeyHash, err = msg.GetHash(KeyHash); err != nil {
+		return fmt.Errorf("GetHash(KeyHash): %v", err)
+	}
+	return nil
+}