1 files changed, 32 insertions, 0 deletions
diff --git a/pkg/policy/policy.go b/pkg/policy/policy.go
new file mode 100644
index 0000000..b4fe920
--- /dev/null
+++ b/pkg/policy/policy.go
@@ -0,0 +1,32 @@
+package policy
+
+import (
+	"git.sigsum.org/sigsum-lib-go/pkg/types"
+)
+
+type Policy interface {
+	// Logs returns the list of known logs.  It is needed so that an
+	// appropriate log can be picked when submitting a signed checksum.
+	Logs() []Log
+
+	// ShardHint returns a recommended shard hint.
+	ShardHint() uint64
+
+	// Verify checks if a cosigned tree head is trustworthy.  On success,
+	// any invalid or unknown cosignatures may be removed.
+	Verify(*types.CosignedTreeHead) error
+}
+
+type Log struct {
+	Name       string
+	LogURL     string
+	PublicKey  types.PublicKey
+	ShardStart uint64
+	TrustUntil uint64
+}
+
+type Witness struct {
+	Name       string
+	PublicKey  types.PublicKey
+	TrustUntil uint64
+}