v4.19.13 snapshot.
diff --git a/security/selinux/ss/context.h b/security/selinux/ss/context.h
new file mode 100644
index 0000000..2260c44
--- /dev/null
+++ b/security/selinux/ss/context.h
@@ -0,0 +1,164 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A security context is a set of security attributes
+ * associated with each subject and object controlled
+ * by the security policy. Security contexts are
+ * externally represented as variable-length strings
+ * that can be interpreted by a user or application
+ * with an understanding of the security policy.
+ * Internally, the security server uses a simple
+ * structure. This structure is private to the
+ * security server and can be changed without affecting
+ * clients of the security server.
+ *
+ * Author : Stephen Smalley, <sds@tycho.nsa.gov>
+ */
+#ifndef _SS_CONTEXT_H_
+#define _SS_CONTEXT_H_
+
+#include "ebitmap.h"
+#include "mls_types.h"
+#include "security.h"
+
+/*
+ * A security context consists of an authenticated user
+ * identity, a role, a type and a MLS range.
+ */
+struct context {
+ u32 user;
+ u32 role;
+ u32 type;
+ u32 len; /* length of string in bytes */
+ struct mls_range range;
+ char *str; /* string representation if context cannot be mapped. */
+};
+
+static inline void mls_context_init(struct context *c)
+{
+ memset(&c->range, 0, sizeof(c->range));
+}
+
+static inline int mls_context_cpy(struct context *dst, struct context *src)
+{
+ int rc;
+
+ dst->range.level[0].sens = src->range.level[0].sens;
+ rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
+ if (rc)
+ goto out;
+
+ dst->range.level[1].sens = src->range.level[1].sens;
+ rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
+ if (rc)
+ ebitmap_destroy(&dst->range.level[0].cat);
+out:
+ return rc;
+}
+
+/*
+ * Sets both levels in the MLS range of 'dst' to the low level of 'src'.
+ */
+static inline int mls_context_cpy_low(struct context *dst, struct context *src)
+{
+ int rc;
+
+ dst->range.level[0].sens = src->range.level[0].sens;
+ rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
+ if (rc)
+ goto out;
+
+ dst->range.level[1].sens = src->range.level[0].sens;
+ rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[0].cat);
+ if (rc)
+ ebitmap_destroy(&dst->range.level[0].cat);
+out:
+ return rc;
+}
+
+/*
+ * Sets both levels in the MLS range of 'dst' to the high level of 'src'.
+ */
+static inline int mls_context_cpy_high(struct context *dst, struct context *src)
+{
+ int rc;
+
+ dst->range.level[0].sens = src->range.level[1].sens;
+ rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[1].cat);
+ if (rc)
+ goto out;
+
+ dst->range.level[1].sens = src->range.level[1].sens;
+ rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
+ if (rc)
+ ebitmap_destroy(&dst->range.level[0].cat);
+out:
+ return rc;
+}
+
+static inline int mls_context_cmp(struct context *c1, struct context *c2)
+{
+ return ((c1->range.level[0].sens == c2->range.level[0].sens) &&
+ ebitmap_cmp(&c1->range.level[0].cat, &c2->range.level[0].cat) &&
+ (c1->range.level[1].sens == c2->range.level[1].sens) &&
+ ebitmap_cmp(&c1->range.level[1].cat, &c2->range.level[1].cat));
+}
+
+static inline void mls_context_destroy(struct context *c)
+{
+ ebitmap_destroy(&c->range.level[0].cat);
+ ebitmap_destroy(&c->range.level[1].cat);
+ mls_context_init(c);
+}
+
+static inline void context_init(struct context *c)
+{
+ memset(c, 0, sizeof(*c));
+}
+
+static inline int context_cpy(struct context *dst, struct context *src)
+{
+ int rc;
+
+ dst->user = src->user;
+ dst->role = src->role;
+ dst->type = src->type;
+ if (src->str) {
+ dst->str = kstrdup(src->str, GFP_ATOMIC);
+ if (!dst->str)
+ return -ENOMEM;
+ dst->len = src->len;
+ } else {
+ dst->str = NULL;
+ dst->len = 0;
+ }
+ rc = mls_context_cpy(dst, src);
+ if (rc) {
+ kfree(dst->str);
+ return rc;
+ }
+ return 0;
+}
+
+static inline void context_destroy(struct context *c)
+{
+ c->user = c->role = c->type = 0;
+ kfree(c->str);
+ c->str = NULL;
+ c->len = 0;
+ mls_context_destroy(c);
+}
+
+static inline int context_cmp(struct context *c1, struct context *c2)
+{
+ if (c1->len && c2->len)
+ return (c1->len == c2->len && !strcmp(c1->str, c2->str));
+ if (c1->len || c2->len)
+ return 0;
+ return ((c1->user == c2->user) &&
+ (c1->role == c2->role) &&
+ (c1->type == c2->type) &&
+ mls_context_cmp(c1, c2));
+}
+
+#endif /* _SS_CONTEXT_H_ */
+