summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--guix/build/syscalls.scm16
-rw-r--r--tests/syscalls.scm26
2 files changed, 42 insertions, 0 deletions
diff --git a/guix/build/syscalls.scm b/guix/build/syscalls.scm
index cff010648a..3f0a0c92f8 100644
--- a/guix/build/syscalls.scm
+++ b/guix/build/syscalls.scm
@@ -54,6 +54,7 @@
CLONE_NEWPID
CLONE_NEWNET
clone
+ setns
IFF_UP
IFF_BROADCAST
@@ -313,6 +314,21 @@ Unlike the fork system call, clone accepts FLAGS that specify which resources
are shared between the parent and child processes."
(proc syscall-id flags %null-pointer))))
+(define setns
+ (let* ((ptr (dynamic-func "setns" (dynamic-link)))
+ (proc (pointer->procedure int ptr (list int int))))
+ (lambda (fdes nstype)
+ "Reassociate the current process with the namespace specified by FDES, a
+file descriptor obtained by opening a /proc/PID/ns/* file. NSTYPE specifies
+which type of namespace the current process may be reassociated with, or 0 if
+there is no such limitation."
+ (let ((ret (proc fdes nstype))
+ (err (errno)))
+ (unless (zero? ret)
+ (throw 'system-error "setns" "~d ~d: ~A"
+ (list fdes nstype (strerror err))
+ (list err)))))))
+
;;;
;;; Packed structures.
diff --git a/tests/syscalls.scm b/tests/syscalls.scm
index 4bc6f0332c..9b8ac9e603 100644
--- a/tests/syscalls.scm
+++ b/tests/syscalls.scm
@@ -90,6 +90,32 @@
((_ . status)
(= 42 (status:exit-val status))))))))
+(test-assert "setns"
+ (match (clone (logior CLONE_NEWUSER SIGCHLD))
+ (0 (primitive-exit 0))
+ (clone-pid
+ (match (pipe)
+ ((in . out)
+ (match (primitive-fork)
+ (0
+ (close in)
+ ;; Join the user namespace.
+ (call-with-input-file (user-namespace clone-pid)
+ (lambda (port)
+ (setns (port->fdes port) 0)))
+ (write 'done out)
+ (close out)
+ (primitive-exit 0))
+ (fork-pid
+ (close out)
+ ;; Wait for the child process to join the namespace.
+ (read in)
+ (let ((result (and (equal? (readlink (user-namespace clone-pid))
+ (readlink (user-namespace fork-pid))))))
+ ;; Clean up.
+ (waitpid clone-pid)
+ (waitpid fork-pid)
+ result))))))))
(test-assert "all-network-interfaces"
(match (all-network-interfaces)