Add signal support - exit on signal

kernel/syscall/privilege.rs

@@ -0,0 +1,85 @@
+use collections::Vec;
+
+use context;
+use scheme;
+use syscall::error::*;
+use syscall::validate::validate_slice;
+
+pub fn getegid() -> Result<usize> {
+    let contexts = context::contexts();
+    let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+    let context = context_lock.read();
+    Ok(context.egid as usize)
+}
+
+pub fn geteuid() -> Result<usize> {
+    let contexts = context::contexts();
+    let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+    let context = context_lock.read();
+    Ok(context.euid as usize)
+}
+
+pub fn getgid() -> Result<usize> {
+    let contexts = context::contexts();
+    let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+    let context = context_lock.read();
+    Ok(context.rgid as usize)
+}
+
+pub fn getuid() -> Result<usize> {
+    let contexts = context::contexts();
+    let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+    let context = context_lock.read();
+    Ok(context.ruid as usize)
+}
+
+pub fn setgid(gid: u32) -> Result<usize> {
+    let contexts = context::contexts();
+    let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+    let mut context = context_lock.write();
+    if context.egid == 0 {
+        context.rgid = gid;
+        context.egid = gid;
+        Ok(0)
+    } else {
+        Err(Error::new(EPERM))
+    }
+}
+
+pub fn setuid(uid: u32) -> Result<usize> {
+    let contexts = context::contexts();
+    let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+    let mut context = context_lock.write();
+    if context.euid == 0 {
+        context.ruid = uid;
+        context.euid = uid;
+        Ok(0)
+    } else {
+        Err(Error::new(EPERM))
+    }
+}
+
+pub fn setns(name_ptrs: &[[usize; 2]]) -> Result<usize> {
+    let mut names = Vec::new();
+    for name_ptr in name_ptrs {
+        names.push(validate_slice(name_ptr[0] as *const u8, name_ptr[1])?);
+    }
+
+    let from = {
+        let contexts = context::contexts();
+        let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+        let context = context_lock.read();
+        context.scheme_ns
+    };
+
+    let to = scheme::schemes_mut().setns(from, &names)?;
+
+    {
+        let contexts = context::contexts();
+        let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
+        let mut context = context_lock.write();
+        context.scheme_ns = to;
+    }
+
+    Ok(0)
+}