1 files changed, 62 insertions, 0 deletions
diff --git a/descriptor/descriptor.go b/descriptor/descriptor.go
new file mode 100644
index 0000000..267a401
--- /dev/null
+++ b/descriptor/descriptor.go
@@ -0,0 +1,62 @@
+package descriptor
+
+import (
+	"bytes"
+	"fmt"
+
+	"crypto"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/json"
+	"io/ioutil"
+)
+
+// Operator is an stfe log operator that runs zero or more logs
+type Operator struct {
+	Name  string `json:"name"`
+	Email string `json:"email"`
+	Logs  []*Log `json:"logs"`
+}
+
+// Log is a collection of immutable stfe log parameters
+type Log struct {
+	Id        []byte                `json:"id"`                // H(PublicKey)
+	PublicKey []byte                `json:"public_key"`        // DER-encoded SubjectPublicKeyInfo
+	Scheme    tls.SignatureScheme   `json:"signature_scheme"`  // Signature schemes used by the log (RFC 8446, §4.2.3)
+	Schemes   []tls.SignatureScheme `json:"signature_schemes"` // Signature schemes that submitters can use (RFC 8446, §4.2.3)
+	MaxChain  uint8                 `json:"max_chain"`         // maximum certificate chain length
+	BaseUrl   string                `json:"base_url"`          // E.g., example.com/st/v1
+}
+
+func FindLog(ops []Operator, logId []byte) (*Log, error) {
+	for _, op := range ops {
+		for _, log := range op.Logs {
+			if bytes.Equal(logId, log.Id) {
+				return log, nil
+			}
+		}
+	}
+	return nil, fmt.Errorf("no such log: %s", base64.StdEncoding.EncodeToString(logId))
+}
+
+// LoadOperators loads a list of json-encoded log operators from a given path
+func LoadOperators(path string) ([]Operator, error) {
+	blob, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("failed reading log operators: %v", err)
+	}
+	var ops []Operator
+	if err := json.Unmarshal(blob, &ops); err != nil {
+		return nil, fmt.Errorf("failed decoding log operators: %v", err)
+	}
+	return ops, nil
+}
+
+func (l *Log) Key() crypto.PublicKey {
+	k, err := x509.ParsePKIXPublicKey(l.PublicKey)
+	if err != nil {
+		panic("TODO: make a new function and parse public key there")
+	}
+	return k
+}