From e6768bdf903d4f9abeddd9c1fe742becf8b4ab8a Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Sun, 27 Dec 2015 12:46:54 +0000
Subject: [PATCH] kernel: start adding functions and files for "level 2"
 functionality

This is the bigger stuff that won't fit well on a small 8bit box but which
isn't by any means essential.
---
 Kernel/include/level2.h |  30 +++++++++++
 Kernel/level2.c         |  13 +++++
 Kernel/syscall_level2.c | 113 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 156 insertions(+)
 create mode 100644 Kernel/include/level2.h
 create mode 100644 Kernel/level2.c
 create mode 100644 Kernel/syscall_level2.c

diff --git a/Kernel/include/level2.h b/Kernel/include/level2.h
new file mode 100644
index 00000000..7b3c4931
--- /dev/null
+++ b/Kernel/include/level2.h
@@ -0,0 +1,30 @@
+/* Resource limits only exist on LEVEL_2 systems */
+
+#define NRLIMIT		9
+
+#define RLIMIT_AS	0
+#define RLIMIT_CORE	1
+#define RLIMIT_CPU	2
+#define RLIMIT_DATA	3
+#define RLIMIT_FSIZE	4
+#define RLIMIT_NOFILE	5
+#define RLIMIT_NPROC	6
+#define RLIMIT_RSS	7
+#define RLIMIT_STACK	8
+
+typedef uint32_t rlimit_t
+
+#define RLIM_INFINITY 0xFFFFFFFFUL
+
+struct rlimit {
+    rlim_t rlim_cur;
+    rlim_t rlim_max;
+};
+
+
+extern int in_group(uint16_t gid);
+
+extern arg_t _setgroups(void);
+extern arg_t _getgroups(void);
+extern arg_t _getrlimit(void);
+extern arg_t _setrlimit(void);
diff --git a/Kernel/level2.c b/Kernel/level2.c
new file mode 100644
index 00000000..53bf780f
--- /dev/null
+++ b/Kernel/level2.c
@@ -0,0 +1,13 @@
+#include <kernel.h>
+#include <kdata.h>
+#include <printf.h>
+
+int in_group(uint16_t gid)
+{
+	uint16_t *g = udata.u_group;
+	uint16_t *p = g + udata.u_ngroup;
+	while(g < p)
+		if (*g++ == gid)
+			return 1;
+	return 0;
+}
diff --git a/Kernel/syscall_level2.c b/Kernel/syscall_level2.c
new file mode 100644
index 00000000..06b3fa3c
--- /dev/null
+++ b/Kernel/syscall_level2.c
@@ -0,0 +1,113 @@
+#include <kernel.h>
+#include <version.h>
+#include <kdata.h>
+#include <printf.h>
+
+/*******************************************
+  setgroups (ngroup, groups)     Function ??
+  int ngroup;
+  const uint16_t *groups;
+ *******************************************/
+#define ngroup (int)udata.u_argn
+#define groups (uint16_t *)udata.u_argn1
+
+arg_t _setgroups(void)
+{
+	if (esuper())
+		return -1;
+	if (ngroup < 0 || ngroup > NGROUP) {
+		udata.u_error = EINVAL;
+		return -1
+	}
+	if (ngroup && uget(groups, udata.u_groups, ngroup * sizeof(uint16_t)))
+		return -1;
+	udata.u_ngroup = ngroup;
+	return 0;
+}
+
+#undef ngroup
+#undef groups
+
+/*******************************************
+  getgroups (ngroup, groups)     Function ??
+  int ngroup;
+  uint16_t *groups;
+ *******************************************/
+#define ngroup (int)udata.u_argn
+#define groups (uint16_t *)udata.u_argn1
+
+arg_t _getgroups(void)
+{
+	if (groups == 0)
+		return udata.u_ngroup;
+	if (ngroup < udata.u_ngroup) {
+		udata.u_error = EINVAL;
+		return;
+	}
+	if (uput(groups, udata.u_groups, ngroup * sizeof(uint16_t)) < 0)
+		return -1;
+	return udata.u_ngroup;
+}
+
+#undef ngroup
+#undef groups
+
+/*******************************************
+  getrlimit (res, rlimit)        Function ??
+  int res;
+  struct rlimit *rlim;
+ *******************************************/
+
+#define res (int)udata.u_argn
+#define rlim (struct rlimit *)udata.u_argn1
+
+arg_t _getrlimit(void)
+{
+	if (res < 0 || res >= NRLIMIT) {
+		udata.u_error = EINVAL;
+		return -1;
+	}
+	return uput(rlim, udata.u_rlimit + res, sizeof(struct rlimit));
+}
+
+#undef res
+#undef rlim
+
+/*******************************************
+  setrlimit (res, rlimit)        Function ??
+  int res;
+  const struct rlimit *rlim;
+ *******************************************/
+
+#define res (int)udata.u_argn
+#define rlim (struct rlimit *)udata.u_argn1
+
+arg_t _setrlimit(void)
+{
+	staticfast struct rlimit r;
+	struct rlimit *o;
+
+	if (res < 0 || res >= NRLIMIT)
+		goto bad;
+
+	if (uget(rlim, &r, sizeof(struct rlimit)))
+		return -1;
+
+	o = uata.u_rlimit + res;
+	if (r.rlim_cur > r.rlim_max)
+		goto bad;
+
+	/* Securit check */
+	if ((r.rlim_cur > o->rlim_max || r.rlim_max > o->rlim_max) && esuper())
+		return -1;
+	o->rlim_cur = r.rlim_cur;
+	o->rlim_max = r.rlim_max;
+	return 0;
+bad:	
+	udata.u_error = EINVAL;
+	return -1;
+}
+
+#undef res
+#undef rlim
+
-- 
2.34.1