note sharding secrets

data/sharing_secrest.md

@@ -0,0 +1,23 @@
+---
+title: "Sharing Secrets"
+tags: [ "data", "death", "secrets", "ssss" ]
+---
+
+You can share parts of a secret with multiple people, so only some of them need to agree to see the secret.
+
+Install `ssss`, then decide on the total number of secrets (`N`), and the threshold of people who must share their shard of the secret in order to reveal the secret.
+
+```bash
+N=5
+T=3
+FILE=secret.txt
+fortune | ssss-split -t $T -n $N > $FILE
+```
+Each shard is a line inside secret.txt.
+
+Check it's working:
+
+```bash
+head -n $T $FILE | ssss-combine -t $T
+tail -n $T $FILE | ssss-combine -t $T
+```