Use cert designators for sq toolbox packet dump.

- See #207.

src/cli/toolbox/packet.rs

@@ -13,6 +13,7 @@ use crate::cli::types::ClapData;
 use crate::cli::types::FileOrStdin;
 use crate::cli::types::FileOrStdout;
 use crate::cli::types::SessionKey;
+use crate::cli::types::cert_designator::*;
 
 #[derive(Parser, Debug)]
 #[clap(
@@ -60,12 +61,20 @@ To inspect encrypted messages, either supply the session key, or see \
     after_help = DUMP_EXAMPLES,
 )]
 pub struct DumpCommand {
+    #[command(flatten)]
+    pub cert: CertDesignators<CertUserIDEmailFileArgs,
+                              CertPrefix,
+                              OneOptionalValue,
+                              PacketDumpDoc>,
+
     #[clap(
         default_value_t = FileOrStdin::default(),
         help = FileOrStdin::HELP_OPTIONAL,
         value_name = FileOrStdin::VALUE_NAME,
+        conflicts_with_all = ["cert", "cert-userid", "cert-email", "cert-file"],
     )]
     pub input: FileOrStdin,
+
     #[clap(
         default_value_t = FileOrStdout::default(),
         help = FileOrStdout::HELP_OPTIONAL,
@@ -142,6 +151,26 @@ secret key file.",
 };
 test_examples!(sq_toolbox_packet_dump, DUMP_EXAMPLES);
 
+/// Documentation for the cert designators for the toolbox packet dump
+/// command.
+pub struct PacketDumpDoc {}
+
+impl AdditionalDocs for PacketDumpDoc {
+    fn help(arg: &'static str, help: &'static str) -> clap::builder::StyledStr {
+        match arg {
+            "file" =>
+                "Dump the packets of the cert read from PATH"
+                .into(),
+            _ => {
+                debug_assert!(help.starts_with("Use certificates"));
+                help.replace("Use certificates",
+                             "Dump the packets of the certificate")
+                    .into()
+            },
+        }
+    }
+}
+
 #[derive(Debug, Args)]
 #[clap(
     about = "Unwrap an encryption container",

src/commands/toolbox/packet.rs

@@ -8,6 +8,7 @@ use terminal_size::terminal_size;
 
 use sequoia_openpgp as openpgp;
 use openpgp::{
+    KeyHandle,
     armor::{
         Kind,
         ReaderMode,
@@ -20,6 +21,7 @@ use openpgp::{
         PacketParserBuilder,
         PacketParserResult,
     },
+    serialize::SerializeInto,
 };
 use openpgp::serialize::stream::Message;
 
@@ -44,7 +46,27 @@ pub fn dispatch(sq: Sq, command: Command)
     tracer!(TRACE, "packet::dispatch");
     match command.subcommand {
         Subcommands::Dump(command) => {
-            let mut input = command.input.open()?;
+            let mut input = if command.cert.is_empty() {
+                if let Some(path) = command.input.inner() {
+                    if ! path.exists() &&
+                        format!("{}", command.input).parse::<KeyHandle>().is_ok() {
+                            wprintln!("The file {} does not exist, \
+                                       did you mean \"sq toolbox packet dump \
+                                       --cert {}\"?",
+                                      path.display(), path.display());
+                        }
+                }
+
+                Box::new(command.input.open()?)
+                    as Box<dyn io::Read + Send + Sync>
+            } else {
+                let cert = sq.resolve_cert(&command.cert, 0)?.0;
+                let bytes = cert.as_tsk().to_vec()
+                    .context("Serializing certificate")?;
+
+                Box::new(io::Cursor::new(bytes))
+            };
+
             let output_type = command.output;
             let mut output = output_type.create_unsafe(&sq)?;