notes: renew gpg expired key

notes/gpg.md

@@ -0,0 +1,47 @@
+# Renew expired key 
+
+List the available keys.
+
+```console
+$ gpg --list-keys
+-------------------------------
+pub   rsa3072/0x121D4302A64B2261 2020-10-12 [SC] [expired: 2022-10-12]
+      Key fingerprint = 2DE4 E864 E515 16D7 9121  CF11 121D 4302 A64B 2261
+uid                   [ expired] Gabriel Volpe <volpegabriel@gmail.com>
+```
+
+Edit the key.
+
+```console
+$ gpg --edit-key 2DE4E864E51516D79121CF11121D4302A64B2261
+Secret key is available.
+
+sec  rsa3072/0x121D4302A64B2261
+     created: 2020-10-12  expired: 2022-10-12  usage: SC
+     trust: unknown       validity: expired
+ssb  rsa3072/0xC2C299648D89952E
+     created: 2020-10-12  expired: 2022-10-12  usage: E
+[ expired] (1). Gabriel Volpe <volpegabriel@gmail.com>
+```
+
+Update its expiration (type `key 1` to also update the subkey `ssb`).
+
+```console
+gpg> expire
+Changing expiration time for a subkey.
+Please specify how long the key should be valid.
+         0 = key does not expire
+      <n>  = key expires in n days
+      <n>w = key expires in n weeks
+      <n>m = key expires in n months
+      <n>y = key expires in n years
+Key is valid for? (0) 8y
+Key expires at Mon 14 Oct 2030 12:16:17 PM CEST
+Is this correct? (y/N) y
+
+gpg> key 1
+gpg> expire # same procedure here with ssb
+gpg> save
+```
+
+Source: https://unix.stackexchange.com/questions/552707/how-to-renew-an-expired-encryption-subkey-with-gpg