pvattest: Add -i -o option variant for check

Most pvattest subcommands use the command line option -i <input> and -o
<output> to specify file input and output respectively. pvattest check
however only uses positional arguments for <input> and <output>, e.g.

$ pvattest check input.bin output.yaml

This provides an inconsistent user interface within the tool and may
confuse users.

Add the command -i and -o option to the check subcommand to bring it in
line with the rest of the tool.

$ pvattest check -i input.bin -o output.yaml

Reviewed-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

rust/pvattest/src/cli.rs

@@ -217,12 +217,20 @@ pub enum OutputType {
 #[derive(Args, Debug)]
 pub struct CheckOpt {
     /// Specify the attestation response to check whether the policies are validated.
-    #[arg(value_name = "IN", value_hint = ValueHint::FilePath,)]
-    pub input: PathBuf,
+    #[arg(short, long, value_name = "FILE", value_hint = ValueHint::FilePath,)]
+    input: Option<PathBuf>,
+
+    /// Specify the attestation response to check whether the policies are validated.
+    #[arg(value_name = "IN", value_hint = ValueHint::FilePath, required_unless_present("input"), conflicts_with("input"))]
+    input_pos: Option<PathBuf>,
 
     /// Specify the output file for the check result.
-    #[arg(value_name = "OUT", value_hint = ValueHint::FilePath,)]
-    pub output: PathBuf,
+    #[arg(short, long, value_name = "FILE", value_hint = ValueHint::FilePath,)]
+    output: Option<PathBuf>,
+
+    /// Specify the output file for the check result.
+    #[arg(value_name = "OUT", value_hint = ValueHint::FilePath, required_unless_present("output"), conflicts_with("output"))]
+    output_pos: Option<PathBuf>,
 
     /// Define the output format.
     #[arg(long, value_enum, default_value_t)]
@@ -300,6 +308,30 @@ pub struct CheckOpt {
     pub firmware_verify_url: Option<String>,
 }
 
+#[derive(Debug)]
+pub struct CheckOptIO<'a> {
+    pub input: &'a PathBuf,
+    pub output: &'a PathBuf,
+}
+
+impl<'a> From<&'a CheckOpt> for CheckOptIO<'a> {
+    fn from(value: &'a CheckOpt) -> Self {
+        let input = match (&value.input, &value.input_pos) {
+            (None, Some(i)) => i,
+            (Some(i), None) => i,
+            (Some(_), Some(_)) => unreachable!(),
+            (None, None) => unreachable!(),
+        };
+        let output = match (&value.output, &value.output_pos) {
+            (None, Some(o)) => o,
+            (Some(o), None) => o,
+            (Some(_), Some(_)) => unreachable!(),
+            (None, None) => unreachable!(),
+        };
+        Self { input, output }
+    }
+}
+
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, ValueEnum, Debug)]
 pub enum HostKeyCheckPolicy {
     /// Check the host-key used for the attestation request.

rust/pvattest/src/cmd/check.rs

@@ -12,7 +12,12 @@ use self::{
     secret_store::secret_store_check,
     secret_store::SecretStoreCheck,
 };
-use crate::{additional::AttestationResult, cli::CheckOpt, exchange::ExchangeFormatResponse};
+use crate::{
+    additional::AttestationResult,
+    cli::{CheckOpt, CheckOptIO},
+    exchange::ExchangeFormatResponse,
+};
+
 use anyhow::Result;
 use log::{debug, info, warn};
 use pv::{
@@ -104,7 +109,8 @@ pub struct CheckResult<'a> {
 
 /// Perform the policy checks
 pub fn check(opt: &CheckOpt) -> Result<ExitCode> {
-    let mut input = open_file(&opt.input)?;
+    let opt_io = CheckOptIO::from(opt);
+    let mut input = open_file(opt_io.input)?;
     let inp = ExchangeFormatResponse::read(&mut input)?;
     let auth = AttestationRequest::auth_bin(inp.arcb())?;
     let att_res = AttestationResult::from_exchange(&inp, auth.flags())?;
@@ -139,7 +145,7 @@ pub fn check(opt: &CheckOpt) -> Result<ExitCode> {
     };
 
     debug!("res {res:?}");
-    let output = create_file(&opt.output)?;
+    let output = create_file(opt_io.output)?;
     serde_yaml::to_writer(output, &res)?;
 
     match res.successful {