feat: add pem export

src/Altinn.Cli/src/Altinn.Cli.Jwks/Commands/ExportCommand.cs

@@ -11,5 +11,6 @@ public ExportCommand()
     {
         AddCommand(new ExportKeyCommand());
         AddCommand(new ExportMaskinportenCommand());
+        AddCommand(new ExportPemCommand());
     }
 }

src/Altinn.Cli/src/Altinn.Cli.Jwks/Commands/ExportMaskinportenCommand.cs

@@ -1,5 +1,4 @@
 using Altinn.Cli.Jwks.Stores;
-using System.Buffers.Text;
 using System.CommandLine;
 using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
@@ -27,7 +26,7 @@
         this.SetHandler(ExecuteAsync, Console, StoreOption, NameArg, ProdOption, CancellationToken);
     }
 
     private async Task<int> ExecuteAsync(
         IConsole console,
         JsonWebKeySetStore store,
         string name,

src/Altinn.Cli/src/Altinn.Cli.Jwks/Commands/ExportPemCommand.cs

@@ -0,0 +1,62 @@
+using Altinn.Cli.Jwks.Stores;
+using Microsoft.IdentityModel.Tokens;
+using System.CommandLine;
+using System.CommandLine.IO;
+using System.Diagnostics.CodeAnalysis;
+using System.Security.Cryptography;
+
+namespace Altinn.Cli.Jwks.Commands;
+
+[ExcludeFromCodeCoverage]
+internal class ExportPemCommand
+    : BaseCommand
+{
+    public static Argument<string> NameArg { get; }
+        = new Argument<string>("name", "Name of the integration to generate JWKs for.");
+
+    public static Option<bool> ProdOption { get; }
+        = new Option<bool>(
+            aliases: ["--prod", "-p"],
+            description: "Generate PROD keys. Defaults to true unless --test is specified.");
+
+    public ExportPemCommand()
+        : base("pem", "Export a public key in pem format")
+    {
+        AddArgument(NameArg);
+        AddOption(ProdOption);
+
+        this.SetHandler(ExecuteAsync, Console, StoreOption, NameArg, ProdOption, CancellationToken);
+    }
+
+    private async Task<int> ExecuteAsync(
+        IConsole console,
+        JsonWebKeySetStore store,
+        string name,
+        bool prod,
+        CancellationToken cancellationToken)
+    {
+        var environment = prod ? JsonWebKeySetEnvironment.Prod : JsonWebKeySetEnvironment.Test;
+        var keySet = await store.GetKeySet(name, environment, JsonWebKeySetVariant.Public, cancellationToken);
+
+        var signingKey = keySet.GetSigningKeys()[^1];
+        switch (signingKey)
+        {
+            case RsaSecurityKey rsa:
+                WriteRsa(console, rsa);
+                break;
+
+            default:
+                console.Error.WriteLine("Unsupported key type.");
+                return 1;
+        }
+
+        return 0;
+    }
+
+    private void WriteRsa(IConsole console, RsaSecurityKey key)
+    {
+        var rsa = key.Rsa ?? RSA.Create(key.Parameters);
+        var pem = rsa.ExportSubjectPublicKeyInfoPem();
+        console.Out.WriteLine(pem);
+    }
+}

src/Altinn.Cli/src/Altinn.Cli.Jwks/Properties/launchSettings.json

@@ -23,6 +23,12 @@
       "commandLineArgs": "--store ./test-keys export key br --base64",
       "workingDirectory": "obj",
       "hotReloadEnabled": false
+    },
+    "export key pem": {
+      "commandName": "Project",
+      "commandLineArgs": "--store ./test-keys export pem br",
+      "workingDirectory": "obj",
+      "hotReloadEnabled": false
     }
   }
 }