From e57f9bf6ca7fa27b6d44029658d565ae093606b8 Mon Sep 17 00:00:00 2001
From: Ian Moffett <ian@osmora.org>
Date: Wed, 9 Jul 2025 19:59:37 -0400
Subject: kernel: ucred: Add SYS_getuid

Signed-off-by: Ian Moffett <ian@osmora.org>
---
 sys/include/sys/syscall.h |  1 +
 sys/include/sys/ucred.h   |  2 ++
 sys/kern/kern_cred.c      | 19 +++++++++++++++++++
 sys/kern/kern_syscall.c   |  1 +
 4 files changed, 23 insertions(+)

(limited to 'sys')

diff --git a/sys/include/sys/syscall.h b/sys/include/sys/syscall.h
index 05288f4..51c2579 100644
--- a/sys/include/sys/syscall.h
+++ b/sys/include/sys/syscall.h
@@ -57,6 +57,7 @@
 #define SYS_getpid  16
 #define SYS_getppid 17
 #define SYS_setuid  18
+#define SYS_getuid  19
 
 #if defined(_KERNEL)
 /* Syscall return value and arg type */
diff --git a/sys/include/sys/ucred.h b/sys/include/sys/ucred.h
index b44a7fe..f8cbbe0 100644
--- a/sys/include/sys/ucred.h
+++ b/sys/include/sys/ucred.h
@@ -48,8 +48,10 @@ struct ucred {
 };
 
 int setuid(uid_t new);
+uid_t getuid(void);
 
 #if defined(_KERNEL)
 scret_t sys_setuid(struct syscall_args *scargs);
+scret_t sys_getuid(struct syscall_args *scargs);
 #endif
 #endif  /* !_SYS_UCRED_H_ */
diff --git a/sys/kern/kern_cred.c b/sys/kern/kern_cred.c
index e1202fc..017b22a 100644
--- a/sys/kern/kern_cred.c
+++ b/sys/kern/kern_cred.c
@@ -56,6 +56,19 @@ setuid(uid_t new)
     return 0;
 }
 
+uid_t
+getuid(void)
+{
+    struct proc *td;
+
+    td = this_td();
+    if (td == NULL) {
+        return -1;
+    }
+
+    return td->cred.ruid;
+}
+
 /*
  * setuid() syscall
  *
@@ -66,3 +79,9 @@ sys_setuid(struct syscall_args *scargs)
 {
     return setuid(scargs->arg0);
 }
+
+scret_t
+sys_getuid(struct syscall_args *scargs)
+{
+    return getuid();
+}
diff --git a/sys/kern/kern_syscall.c b/sys/kern/kern_syscall.c
index 276c7c7..a28d2dd 100644
--- a/sys/kern/kern_syscall.c
+++ b/sys/kern/kern_syscall.c
@@ -58,6 +58,7 @@ scret_t(*g_sctab[])(struct syscall_args *) = {
     sys_getpid, /* SYS_getpid */
     sys_getppid, /* SYS_getppid */
     sys_setuid,  /* SYS_setuid */
+    sys_getuid,  /* SYS_getuid */
 };
 
 const size_t MAX_SYSCALLS = NELEM(g_sctab);
-- 
cgit v1.2.3