chore: split code out into modules

src/main.rs

@@ -1,125 +1,26 @@
-use std::{fs::write, path::PathBuf, time::Duration};
-
-use anyhow::{anyhow, Context, Result};
-use clap::Parser;
-
-use serde::Deserialize;
+use anyhow::{Context, Result};
 
 use sequoia_openpgp::{
     cert::CertBuilder,
     packet::signature::SignatureBuilder,
-    serialize::SerializeInto,
     types::{KeyFlags, SignatureType},
 };
 
-#[derive(Deserialize)]
-struct Spec {
-    primary: KeyConfig,
-    subs: Vec<KeyConfig>,
-    user_ids: Vec<UserIdConfig>,
-    #[serde(flatten)]
-    expiry: Expiry,
-}
+use spec::KeyFlag;
 
-#[derive(Deserialize)]
-struct KeyConfig {
-    flags: Vec<KeyFlag>,
-    cipher_suite: sequoia_openpgp::cert::CipherSuite,
-    #[serde(flatten)]
-    expiry: Expiry,
-}
-
-#[derive(Deserialize)]
-struct UserIdConfig {
-    value: String,
-    #[serde(default)]
-    notation: Vec<(String, String)>,
-}
-
-#[derive(Deserialize)]
-struct Expiry {
-    #[serde(with = "humantime_serde::option", default)]
-    validity_period: Option<Duration>,
-}
-
-#[derive(Deserialize)]
-#[serde(rename_all = "snake_case")]
-enum KeyFlag {
-    Certify,
-    Sign,
-    EncryptForTransport,
-    EncryptAtRest,
-    SplitKey,
-    Authenticate,
-    GroupKey,
-}
-
-#[derive(Parser)]
-#[command(author, version, about, long_about = None)]
-struct Cli {
-    /// Path to the directory it should operate on. Defaults to the current working directory.
-    #[arg(value_name = "DIR")]
-    path: Option<PathBuf>,
-}
-
-struct Paths {
-    spec: PathBuf,
-    secret: PathBuf,
-    public: PathBuf,
-    rev: PathBuf,
-}
-
-impl Paths {
-    fn new(base: PathBuf) -> Paths {
-        let mut spec = base.clone();
-        spec.push("spec.yml");
-        let mut secret = base.clone();
-        secret.push("secret.asc");
-        let mut public = base.clone();
-        public.push("public.asc");
-        let mut rev = base;
-        rev.push("rev.asc");
-        Paths {
-            spec,
-            secret,
-            public,
-            rev,
-        }
-    }
-}
-
-impl KeyFlag {
-    fn apply(&self, flags: sequoia_openpgp::types::KeyFlags) -> sequoia_openpgp::types::KeyFlags {
-        match self {
-            Self::Certify => flags.set_certification(),
-            Self::Sign => flags.set_signing(),
-            Self::EncryptForTransport => flags.set_transport_encryption(),
-            Self::EncryptAtRest => flags.set_storage_encryption(),
-            Self::SplitKey => flags.set_split_key(),
-            Self::Authenticate => flags.set_authentication(),
-            Self::GroupKey => flags.set_group_key(),
-        }
-    }
-}
+mod paths;
+mod setup;
+mod spec;
 
 fn main() -> Result<()> {
-    let cli = Cli::parse();
-    let base_dir = cli
-        .path
-        .ok_or_else(|| anyhow!("No path specified in CLI parameters."))
-        .or_else(|_| std::env::current_dir())
-        .context(
-            "Couldn't get current dir from env, and no path was specified in CLI parameters either",
-        )?;
-    let paths = Paths::new(base_dir);
-    let spec_string = std::fs::read_to_string(&paths.spec)?;
-    let spec: Spec = serde_yaml::from_str(&spec_string)?;
-    let mut primary_key_flags = KeyFlags::empty();
-    for flag in spec.primary.flags {
-        primary_key_flags = flag.apply(primary_key_flags);
-    }
+    let (paths, spec) = crate::setup::setup().context("Failed to setup application")?;
     let mut builder = CertBuilder::new()
-        .set_primary_key_flags(primary_key_flags)
+        .set_primary_key_flags(
+            spec.primary
+                .flags
+                .iter()
+                .fold(KeyFlags::empty(), KeyFlag::fold),
+        )
         .set_validity_period(
             spec.primary
                 .expiry
@@ -128,12 +29,8 @@ fn main() -> Result<()> {
         )
         .set_cipher_suite(spec.primary.cipher_suite);
     for sub_key in spec.subs {
-        let mut sub_key_flags = KeyFlags::empty();
-        for flag in sub_key.flags {
-            sub_key_flags = flag.apply(sub_key_flags);
-        }
         builder = builder.add_subkey_with(
-            sub_key_flags,
+            sub_key.flags.iter().fold(KeyFlags::empty(), KeyFlag::fold),
             sub_key
                 .expiry
                 .validity_period
@@ -145,16 +42,26 @@ fn main() -> Result<()> {
     for user_id in spec.user_ids {
         let mut sig_builder = SignatureBuilder::new(SignatureType::PositiveCertification);
         for (key, value) in user_id.notation {
-            sig_builder = sig_builder.add_notation(key, value, None, false)?;
+            sig_builder = sig_builder
+                .add_notation(key, value, None, false)
+                .context(format!(
+                    "Failed to add notation to signature builder for {}",
+                    &user_id.value
+                ))?;
         }
-        builder = builder.add_userid_with(user_id.value, sig_builder)?;
+        builder = builder
+            .add_userid_with(user_id.value.clone(), sig_builder)
+            .context(format!(
+                "Failed to add user ID {} to certificate builder",
+                &user_id.value
+            ))?;
     }
 
-    let (cert, rev) = builder.generate()?;
-
-    write(&paths.public, cert.armored().to_vec()?)?;
-    write(&paths.secret, cert.as_tsk().armored().to_vec()?)?;
-    write(&paths.rev, cert.insert_packets(rev)?.armored().to_vec()?)?;
-
+    let (cert, rev) = builder
+        .generate()
+        .context("Failed to generate certificate!")?;
+    paths
+        .write(cert, rev)
+        .context("Failed to store certificate!")?;
     Ok(())
 }

src/paths.rs

@@ -0,0 +1,70 @@
+use std::path::{Path, PathBuf};
+
+use anyhow::{Context, Result};
+use sequoia_openpgp::{packet::Signature, serialize::SerializeInto, Cert};
+
+pub(crate) struct Paths {
+    pub(crate) spec: PathBuf,
+    pub(crate) secret: PathBuf,
+    pub(crate) public: PathBuf,
+    pub(crate) rev: PathBuf,
+}
+
+impl Paths {
+    pub(crate) fn new(base: PathBuf) -> Paths {
+        let mut spec = base.clone();
+        spec.push("spec.yml");
+        let mut secret = base.clone();
+        secret.push("secret.asc");
+        let mut public = base.clone();
+        public.push("public.asc");
+        let mut rev = base;
+        rev.push("rev.asc");
+        Paths {
+            spec,
+            secret,
+            public,
+            rev,
+        }
+    }
+    pub(crate) fn write(&self, cert: Cert, rev: Signature) -> Result<()> {
+        self.write_part(Self::public, cert.armored())
+            .context("Failed to write public certificate to file")?;
+        self.write_part(Self::secret, cert.as_tsk().armored())
+            .context("Failed to certificate including private keys to file")?;
+        self.write_part(
+            Self::rev,
+            cert.insert_packets(rev)
+                .context("Failed to write revocation signature packet into certificate")?
+                .armored(),
+        )
+        .context("Failed to write revoked certificate to file")?;
+        Ok(())
+    }
+
+    fn write_part<F, S>(&self, path_selector: F, data: S) -> Result<()>
+    where
+        F: Fn(&Self) -> &Path,
+        S: SerializeInto,
+    {
+        std::fs::write(
+            path_selector(self),
+            SerializeInto::to_vec(&data)
+                .context("Failed to serialize certificate into byte vec")?,
+        )
+        .context("Failed to write serialized certificate into file")?;
+        Ok(())
+    }
+
+    fn public(&self) -> &Path {
+        self.public.as_path()
+    }
+
+    fn secret(&self) -> &Path {
+        self.secret.as_path()
+    }
+
+    fn rev(&self) -> &Path {
+        self.rev.as_path()
+    }
+}

src/setup.rs

@@ -0,0 +1,31 @@
+use std::path::PathBuf;
+
+use anyhow::{anyhow, Context, Result};
+use clap::Parser;
+
+use crate::{paths::Paths, spec::Spec};
+
+#[derive(Parser)]
+#[command(author, version, about, long_about = None)]
+pub(crate) struct Cli {
+    /// Path to the directory it should operate on. Defaults to the current working directory.
+    #[arg(value_name = "DIR")]
+    pub(crate) path: Option<PathBuf>,
+}
+
+pub(crate) fn setup() -> Result<(Paths, Spec)> {
+    let cli = Cli::parse();
+    let base_dir = cli
+        .path
+        .ok_or_else(|| anyhow!("No path specified in CLI parameters."))
+        .or_else(|_| std::env::current_dir())
+        .context(
+            "Couldn't get current dir from env, and no path was specified in CLI parameters either",
+        )?;
+    let paths = Paths::new(base_dir);
+    let spec_string =
+        std::fs::read_to_string(&paths.spec).context("Failed to read spec into string")?;
+    let spec: Spec =
+        serde_yaml::from_str(&spec_string).context("Failed to parse spec from string")?;
+    Ok((paths, spec))
+}

src/spec.rs

@@ -0,0 +1,85 @@
+use std::time::Duration;
+
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+/// Specification for how the OpenPGP certificate is supposed to look like
+pub(crate) struct Spec {
+    /// KeySpec for the primary key
+    pub(crate) primary: KeySpec,
+    /// List of KeySpec elements for the sub keys
+    pub(crate) subs: Vec<KeySpec>,
+    /// List of UserIdSpec elements for the user ids
+    pub(crate) user_ids: Vec<UserIdSpec>,
+    #[serde(flatten)]
+    /// Expiry information
+    pub(crate) expiry: Expiry,
+}
+
+#[derive(Deserialize)]
+/// Specification for how the (sub) key is supposed to be configured
+pub(crate) struct KeySpec {
+    /// List of flags to set for the key, detailing what for and how the key can be used.
+    pub(crate) flags: Vec<KeyFlag>,
+    /// Which kind of cryptography the key is going to use
+    pub(crate) cipher_suite: sequoia_openpgp::cert::CipherSuite,
+    #[serde(flatten)]
+    /// Expiry information
+    pub(crate) expiry: Expiry,
+}
+
+#[derive(Deserialize)]
+/// Specification on how a user ID is supposed to look
+pub(crate) struct UserIdSpec {
+    /// The string value of the user ID itself
+    pub(crate) value: String,
+    #[serde(default)]
+    /// A list of notation keys and values to add to the binding signature of the user ID.
+    pub(crate) notation: Vec<(String, String)>,
+}
+
+#[derive(Deserialize)]
+/// Expiry spec, including right now only a validity period
+pub(crate) struct Expiry {
+    #[serde(with = "humantime_serde::option", default)]
+    /// Validity period, how long a key is supposed to be usable for, starting with the date it was
+    /// created
+    pub(crate) validity_period: Option<Duration>,
+}
+
+#[derive(Deserialize)]
+#[serde(rename_all = "snake_case")]
+/// Flags that can be set for keys
+pub(crate) enum KeyFlag {
+    /// Key can certify
+    Certify,
+    /// Key can sign
+    Sign,
+    /// Key can be used for transport encryption
+    EncryptForTransport,
+    /// Key can be used for encrypting data at rest
+    EncryptAtRest,
+    /// Key is split by a secret-sharing mechanism
+    SplitKey,
+    /// Key can be used for authentication
+    Authenticate,
+    /// Key is in the possession of more than one person
+    GroupKey,
+}
+
+impl KeyFlag {
+    pub(crate) fn fold(
+        flags: sequoia_openpgp::types::KeyFlags,
+        flag: &Self,
+    ) -> sequoia_openpgp::types::KeyFlags {
+        match flag {
+            Self::Certify => flags.set_certification(),
+            Self::Sign => flags.set_signing(),
+            Self::EncryptForTransport => flags.set_transport_encryption(),
+            Self::EncryptAtRest => flags.set_storage_encryption(),
+            Self::SplitKey => flags.set_split_key(),
+            Self::Authenticate => flags.set_authentication(),
+            Self::GroupKey => flags.set_group_key(),
+        }
+    }
+}