// FIXME: many of these are also in ct.proto.

syntax = "proto2";

package ct;

import "ct/proto/tls_options.proto";


message KeyInfo {
  enum KeyType {
    ECDSA = 0;
    RSA = 1;
  }
  optional KeyType type = 1;
  // The serialized public key, PEM-encoded.
  optional string pem_key = 2;
}

// A merkle tree storing just enough hashes to be able to append new leaves
// and obtain the new root_hash, but unable to get arbitrary leaves or hashes
// within the tree.
message CompactMerkleTree {
  optional uint64 tree_size = 1;
  repeated bytes hashes = 2;
}

message CtLogMetadata {
  // The <log_server> path prefix. Responses are bound to the server
  // by this value.
  optional string log_server = 1;
  // The id as per the RFC, i.e., the key hash, base64-encoded.
  optional string log_id = 2;
  optional KeyInfo public_key_info = 3;
}

message CtLogs {
  repeated CtLogMetadata ctlog = 1;
}

message SthResponse {
  optional uint64 tree_size = 1;
  optional uint64 timestamp = 2;
  optional bytes sha256_root_hash = 3;
  optional bytes tree_head_signature = 4;
}

enum VerifyStatus {
  VERIFIED = 0;
  UNVERIFIED = 1;
  VERIFY_ERROR = 2;
}

// Currently just a placeholder proto so that we can add new fields without
// changing the DB schema.
message AuditInfo {
  optional VerifyStatus status = 1;
}

// The STH with additional auditing information such as signature verification
// status.
message AuditedSth {
  optional SthResponse sth = 1;
  optional AuditInfo audit = 2;
}

message EntryResponse {
  optional bytes leaf_input = 1;
  optional bytes extra_data = 2;
}

message ProofByHashResponse {
  optional uint64 leaf_index = 1;
  repeated bytes audit_path = 2;
}

message EntryAndProofResponse {
  optional EntryResponse entry = 1;
  repeated bytes audit_path = 2;
}

message MonitorState {
  optional SthResponse verified_sth = 1;
  // An STH whose leaf entries are yet to be retrieved. Its timestamp and
  // tree_size should both be strictly greater than the one for verified_sth.
  // If not, then this field should be ignored entirely.
  optional SthResponse pending_sth = 2;
  // A compact tree representing the last verified batch of leaves that is
  // is provably-consistent with verified_sth.
  optional CompactMerkleTree verified_tree = 3;
  // A compact tree representing the last unverified batch of leaves.
  optional CompactMerkleTree unverified_tree = 4;
}

enum Version {
  option (tls_enum_opts).max_value = 255;
  V1 = 0;
  // Not part of the I-D, and outside the valid range.
  UNKNOWN_VERSION = 256;
}

enum MerkleLeafType {
  option (tls_enum_opts).max_value = 255;
  TIMESTAMPED_ENTRY = 0;
}

enum LogEntryType {
  option (tls_enum_opts).max_value = 65535;
  X509_ENTRY = 0;
  PRECERT_ENTRY = 1;
}

enum SignatureType {
  option (tls_enum_opts).max_value = 255;
  CERTIFICATE_TIMESTAMP = 0;
  TREE_HASH = 1;
}

message PreCert {
  optional bytes issuer_key_hash = 1 [(tls_opts).fixed_length = 32];
  optional bytes tbs_certificate = 2 [(tls_opts).min_length = 1,
                                      (tls_opts).max_length = 0xffffff];
}

message TimestampedEntry {
  optional uint64 timestamp = 1;
  optional LogEntryType entry_type = 2;
  optional bytes asn1_cert = 3 [(tls_opts).select_field = "entry_type",
                                (tls_opts).select_value = 0,
                                (tls_opts).min_length = 1,
                                (tls_opts).max_length = 0xffffff];
  optional PreCert pre_cert = 4 [(tls_opts).select_field = "entry_type",
                                (tls_opts).select_value = 1];
  optional bytes ct_extensions = 5 [(tls_opts).max_length = 0xffff];
}


message DigitallySignedTimestampedEntry {
  optional Version sct_version = 1;
  optional SignatureType signature_type = 2 [default = CERTIFICATE_TIMESTAMP];
  optional uint64 timestamp = 3;
  optional LogEntryType entry_type = 4;
  optional bytes asn1_cert = 5 [(tls_opts).select_field = "entry_type",
                                (tls_opts).select_value = 0,
                                (tls_opts).min_length = 1,
                                (tls_opts).max_length = 0xffffff];
  optional PreCert pre_cert = 6 [(tls_opts).select_field = "entry_type",
                                (tls_opts).select_value = 1];
  optional bytes ct_extensions = 7 [(tls_opts).min_length = 0,
                                    (tls_opts).max_length = 0xffff];
}

message MerkleTreeLeaf {
  optional Version version = 1;
  optional MerkleLeafType leaf_type = 2;
  optional TimestampedEntry timestamped_entry = 3
      [(tls_opts).select_field = "leaf_type",
       (tls_opts).select_value = 0];
}

message PrecertChainEntry {
  optional bytes pre_certificate = 1 [(tls_opts).min_length = 1,
                                      (tls_opts).max_length = 0xffffff];
  repeated bytes precertificate_chain = 2
      [(tls_opts).min_length = 1,
       (tls_opts).max_length = 0xffffff,
       (tls_opts).max_total_length = 0xffffff];
}

message ExtraData {
  optional LogEntryType entry_type = 1 [(tls_opts).skip = true]; // Prefilled.
  repeated bytes certificate_chain = 2 [(tls_opts).select_field = "entry_type",
                                        (tls_opts).select_value = 0,
                                        (tls_opts).min_length = 1,
                                        (tls_opts).max_length = 0xffffff,
                                        (tls_opts).max_total_length = 0xffffff];
  optional PrecertChainEntry precert_chain_entry = 3
      [(tls_opts).select_field = "entry_type",
       (tls_opts).select_value = 1];
}

message ParsedEntry {
  optional MerkleTreeLeaf merkle_leaf = 1;
  optional ExtraData extra_data = 2;
}

// RFC 5246
message DigitallySigned {
  enum HashAlgorithm {
    option (tls_enum_opts).max_value = 255;
    NONE = 0;
    MD5 = 1;
    SHA1 = 2;
    SHA224 = 3;
    SHA256 = 4;
    SHA384 = 5;
    SHA512 = 6;
  }

  enum SignatureAlgorithm {
    option (tls_enum_opts).max_value = 255;
    ANONYMOUS = 0;
    RSA = 1;
    DSA = 2;
    ECDSA = 3;
  }

  // 1 byte
  optional HashAlgorithm hash_algorithm = 1 [ default = NONE ];
  // 1 byte
  optional SignatureAlgorithm sig_algorithm = 2 [ default = ANONYMOUS ];
  // 0..2^16-1 bytes
  optional bytes signature = 3 [ (tls_opts).min_length = 0,
                                 (tls_opts).max_length = 0xffff ];
}
message LogID {
  // 32 bytes
  optional bytes key_id = 1 [ (tls_opts).fixed_length = 32 ];
}

message SignedCertificateTimestamp {
  optional Version version = 1 [ default = UNKNOWN_VERSION ];
  optional LogID id = 2;
  // UTC time in milliseconds, since January 1, 1970, 00:00.
  optional uint64 timestamp = 3;
  optional bytes extensions = 4 [ (tls_opts).min_length = 0,
                                  (tls_opts).max_length = 0xffff ];
  optional DigitallySigned signature = 5;
}

message SignedCertificateTimestampList {
  repeated bytes sct_list = 1 [ (tls_opts).min_length = 1,
                                (tls_opts).max_length = 0xffff,
                                (tls_opts).max_total_length = 0xffff ];
}