ssh/agent: support smartcard extensions

[Foxboron]

This probably needs a bit more work but this patch allows me to at least serve the requests to add/remove smartcard with the Go crypto/ssh/agent module.

A bit of feedback and/or direction if this is the right approach would be appreciated.

Tested this with a small patch on ssh-tpm-agent.

λ ssh-tpm-agent-dev dev Ɇ » git diff agent/agent.go
diff --git a/agent/agent.go b/agent/agent.go
index 76a2610a613a..7e74f0f4cf3d 100644
--- a/agent/agent.go
+++ b/agent/agent.go
@@ -50,7 +50,10 @@ type Agent struct {
        agents   []agent.ExtendedAgent
 }

-var _ agent.ExtendedAgent = &Agent{}
+var (
+       _ agent.ExtendedAgent  = &Agent{}
+       _ agent.SmartcardAgent = &Agent{}
+)

 func (a *Agent) Extension(extensionType string, contents []byte) ([]byte, error) {
        slog.Debug("called extensions")
@@ -319,6 +322,18 @@ func (a *Agent) Add(key agent.AddedKey) error {
        return nil
 }

+func (a *Agent) AddSmartcard(key agent.AddedSmartcardKey) error {
+       slog.Debug("called addsmartcard")
+       fmt.Println(key.PIN)
+       fmt.Println(key.ReaderID)
+       return nil
+}
+
+func (a *Agent) RemoveSmartcard(key agent.RemovedSmartcardKey) error {
+       slog.Debug("called removesmartcard")
+       return nil
+}
+
 func (a *Agent) Remove(sshkey ssh.PublicKey) error {
        slog.Debug("called remove")
        a.mu.Lock()

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Nicola Murino:

Patch Set 1:

(1 comment)

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Message from Morten Linderud:

Patch Set 1:

(1 comment)

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Message from Nicola Murino:

Patch Set 1:

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