Add sq cert export --local to export non-exportable sigs.

- Fixes #185.

src/cli/cert/export.rs

@@ -90,6 +90,23 @@ pub struct Command {
     )]
     pub binary: bool,
 
+    #[clap(
+        long = "local",
+        help = "Export local (non-exportable) signatures",
+        long_help = "\
+Export local (non-exportable) signatures
+
+By default, non-exportable signatures are not emitted when exporting \
+certificates, certificate components that are only bound by \
+non-exportable signatures are not emitted, and certificates consisting \
+of only non-exportable components are not emitted.
+
+This flag enables exporting of non-exportable signatures, components, \
+and certs.  This is useful for synchronization between ones devices, \
+for example.",
+    )]
+    pub local: bool,
+
     #[clap(
         long,
         conflicts_with_all = [

src/commands/cert/export.rs

@@ -42,7 +42,8 @@ pub fn dispatch(sq: Sq, mut cmd: export::Command) -> Result<()> {
     if cmd.all {
         // Export everything.
         for cert in cert_store.certs()
-            .filter(|c| c.to_cert().map(cert_exportable).unwrap_or(false))
+            .filter(|c| cmd.local
+                    || c.to_cert().map(cert_exportable).unwrap_or(false))
         {
             // Turn parse errors into warnings: we want users to be
             // able to recover as much of their data as possible.
@@ -52,7 +53,11 @@ pub fn dispatch(sq: Sq, mut cmd: export::Command) -> Result<()> {
                             cert.fingerprint())
                 });
             match result {
-                Ok(cert) => cert.export(&mut sink)?,
+                Ok(cert) => if cmd.local {
+                    cert.serialize(&mut sink)?;
+                } else {
+                    cert.export(&mut sink)?;
+                },
                 Err(err) => {
                     print_error_chain(&err);
                     continue;
@@ -86,7 +91,11 @@ pub fn dispatch(sq: Sq, mut cmd: export::Command) -> Result<()> {
         }
 
         for cert in certs.into_iter() {
-            cert.export(&mut sink)?;
+            if cmd.local {
+                cert.serialize(&mut sink)?;
+            } else {
+                cert.export(&mut sink)?;
+            }
             exported_something = true;
         }
     }