From 09da116ccdf674b1f8650360370343ac92fa0f67 Mon Sep 17 00:00:00 2001
From: bjorn3 <17426603+bjorn3@users.noreply.github.com>
Date: Sat, 6 Jan 2024 17:24:34 +0100
Subject: [PATCH] Move /etc/group generation to the installer

This ensures that the gid's for the auto-generated user groups stay in
sync with the gid in /etc/passwd. It also makes it easier to evolve the
format of /etc/group in the future.
---
 config/default.toml | 12 ++++--------
 src/config/mod.rs   |  7 +++++++
 src/config/user.rs  |  7 +++++++
 src/lib.rs          | 47 ++++++++++++++++++++++++++++++++++++++++++++-
 test.toml           | 13 +++++--------
 5 files changed, 69 insertions(+), 17 deletions(-)

diff --git a/config/default.toml b/config/default.toml
index 0a5e7226bd..fef03c7b6e 100644
--- a/config/default.toml
+++ b/config/default.toml
@@ -69,6 +69,10 @@ home = "/root"
 # Password is unset
 password = ""
 
+[groups.sudo]
+gid = 1
+members = ["user"]
+
 [[files]]
 path = "/etc/init.d/00_base"
 data = """
@@ -135,14 +139,6 @@ data = """
 path = "/etc/pkg.d/50_redox"
 data = "https://static.redox-os.org/pkg"
 
-[[files]]
-path = "/etc/group"
-data = """
-root;0;root
-user;1000;user
-sudo;1;user
-"""
-
 [[files]]
 path = "/etc/hostname"
 data = """
diff --git a/src/config/mod.rs b/src/config/mod.rs
index be679f19e1..5f11eff2c5 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -20,6 +20,8 @@ pub struct Config {
     pub files: Vec<file::FileConfig>,
     #[serde(default)]
     pub users: BTreeMap<String, user::UserConfig>,
+    #[serde(default)]
+    pub groups: BTreeMap<String, user::GroupConfig>,
 }
 
 impl Config {
@@ -63,6 +65,7 @@ impl Config {
             packages: other_packages,
             files: other_files,
             users: other_users,
+            groups: other_groups,
         } = other;
 
         self.general.merge(other_general);
@@ -76,5 +79,9 @@ impl Config {
         for (user, user_config) in other_users {
             self.users.insert(user, user_config);
         }
+
+        for (group, group_config) in other_groups {
+            self.groups.insert(group, group_config);
+        }
     }
 }
diff --git a/src/config/user.rs b/src/config/user.rs
index 3b82342048..9e9393de0c 100644
--- a/src/config/user.rs
+++ b/src/config/user.rs
@@ -7,3 +7,10 @@ pub struct UserConfig {
     pub home: Option<String>,
     pub shell: Option<String>,
 }
+
+#[derive(Clone, Debug, Default, Deserialize, Serialize)]
+pub struct GroupConfig {
+    pub gid: Option<u32>,
+    // FIXME move this to the UserConfig struct as extra_groups
+    pub members: Vec<String>,
+}
diff --git a/src/lib.rs b/src/lib.rs
index f70c50d56d..84c5a9d0f3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -181,6 +181,9 @@ pub fn install_dir<P: AsRef<Path>, S: AsRef<str>>(config: Config, output_dir: P,
     let mut passwd = String::new();
     let mut shadow = String::new();
     let mut next_uid = 1000;
+    let mut next_gid = 1000;
+
+    let mut groups = vec![];
 
     for (username, user) in config.users {
         // plaintext
@@ -200,7 +203,11 @@ pub fn install_dir<P: AsRef<Path>, S: AsRef<str>>(config: Config, output_dir: P,
             next_uid = uid + 1;
         }
 
-        let gid = user.gid.unwrap_or(uid);
+        let gid = user.gid.unwrap_or(next_gid);
+
+        if gid >= next_gid {
+            next_gid = gid + 1;
+        }
 
         let name = prompt!(user.name, username.clone(), "{}: name (GECOS) [{}]: ", username, username)?;
         let home = prompt!(user.home, format!("/home/{}", username), "{}: home [/home/{}]: ", username, username)?;
@@ -229,6 +236,19 @@ pub fn install_dir<P: AsRef<Path>, S: AsRef<str>>(config: Config, output_dir: P,
 
         passwd.push_str(&format!("{};{};{};{};file:{};file:{}\n", username, uid, gid, name, home, shell));
         shadow.push_str(&format!("{};{}\n", username, password));
+        groups.push((username.clone(), gid, vec![username]));
+    }
+
+    for (group, group_config) in config.groups {
+        // FIXME this assumes there is no overlap between auto-created groups for users
+        // and explicitly specified groups.
+        let gid = group_config.gid.unwrap_or(next_gid);
+
+        if gid >= next_gid {
+            next_gid = gid + 1;
+        }
+
+        groups.push((group, gid, group_config.members));
     }
 
     if !passwd.is_empty() {
@@ -258,6 +278,31 @@ pub fn install_dir<P: AsRef<Path>, S: AsRef<str>>(config: Config, output_dir: P,
         }.create(&output_dir)?;
     }
 
+    if !groups.is_empty() {
+        let mut groups_data = String::new();
+
+        for (name, gid, members) in groups {
+            use std::fmt::Write;
+            writeln!(groups_data, "{name};{gid};{}", members.join(",")).unwrap();
+
+            println!("Adding group {}:", name);
+            println!("\tGID: {}", gid);
+            println!("\tMembers: {}", members.join(", "));
+        }
+
+        FileConfig {
+            path: "/etc/group".to_string(),
+            data: groups_data,
+            symlink: false,
+            directory: false,
+            // Take defaults
+            mode: None,
+            uid: None,
+            gid: None,
+            recursive_chown: false,
+        }.create(&output_dir)?;
+    }
+
     Ok(())
 }
 
diff --git a/test.toml b/test.toml
index 39c0082dcf..08b9f2be97 100644
--- a/test.toml
+++ b/test.toml
@@ -54,6 +54,11 @@ home = "/root"
 # Password is unset
 password = ""
 
+# Group settings
+[groups.sudo]
+gid = 1
+members = ["user"]
+
 [[files]]
 path = "/etc/init.d/00_base"
 data = """
@@ -118,14 +123,6 @@ data = """
 path = "/etc/pkg.d/50_redox"
 data = "https://static.redox-os.org/pkg"
 
-[[files]]
-path = "/etc/group"
-data = """
-root;0;root
-user;1000;user
-sudo;1;user
-"""
-
 [[files]]
 path = "/etc/hostname"
 data = """