1 files changed, 240 insertions, 0 deletions
diff --git a/security/apparmor/include/file.h b/security/apparmor/include/file.h
new file mode 100644
index 000000000..029cb20e3
--- /dev/null
+++ b/security/apparmor/include/file.h
@@ -0,0 +1,240 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor file mediation function definitions.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ */
+
+#ifndef __AA_FILE_H
+#define __AA_FILE_H
+
+#include <linux/spinlock.h>
+
+#include "domain.h"
+#include "match.h"
+#include "perms.h"
+
+struct aa_profile;
+struct path;
+
+#define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))
+
+#define AA_AUDIT_FILE_MASK	(MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
+				 AA_MAY_CREATE | AA_MAY_DELETE |	\
+				 AA_MAY_GETATTR | AA_MAY_SETATTR | \
+				 AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
+				 AA_EXEC_MMAP | AA_MAY_LINK)
+
+static inline struct aa_file_ctx *file_ctx(struct file *file)
+{
+	return file->f_security + apparmor_blob_sizes.lbs_file;
+}
+
+/* struct aa_file_ctx - the AppArmor context the file was opened in
+ * @lock: lock to update the ctx
+ * @label: label currently cached on the ctx
+ * @perms: the permission the file was opened with
+ */
+struct aa_file_ctx {
+	spinlock_t lock;
+	struct aa_label __rcu *label;
+	u32 allow;
+};
+
+/**
+ * aa_alloc_file_ctx - allocate file_ctx
+ * @label: initial label of task creating the file
+ * @gfp: gfp flags for allocation
+ *
+ * Returns: file_ctx or NULL on failure
+ */
+static inline struct aa_file_ctx *aa_alloc_file_ctx(struct aa_label *label,
+						    gfp_t gfp)
+{
+	struct aa_file_ctx *ctx;
+
+	ctx = kzalloc(sizeof(struct aa_file_ctx), gfp);
+	if (ctx) {
+		spin_lock_init(&ctx->lock);
+		rcu_assign_pointer(ctx->label, aa_get_label(label));
+	}
+	return ctx;
+}
+
+/**
+ * aa_free_file_ctx - free a file_ctx
+ * @ctx: file_ctx to free  (MAYBE_NULL)
+ */
+static inline void aa_free_file_ctx(struct aa_file_ctx *ctx)
+{
+	if (ctx) {
+		aa_put_label(rcu_access_pointer(ctx->label));
+		kfree_sensitive(ctx);
+	}
+}
+
+static inline struct aa_label *aa_get_file_label(struct aa_file_ctx *ctx)
+{
+	return aa_get_label_rcu(&ctx->label);
+}
+
+/*
+ * The xindex is broken into 3 parts
+ * - index - an index into either the exec name table or the variable table
+ * - exec type - which determines how the executable name and index are used
+ * - flags - which modify how the destination name is applied
+ */
+#define AA_X_INDEX_MASK		0x03ff
+
+#define AA_X_TYPE_MASK		0x0c00
+#define AA_X_TYPE_SHIFT		10
+#define AA_X_NONE		0x0000
+#define AA_X_NAME		0x0400	/* use executable name px */
+#define AA_X_TABLE		0x0800	/* use a specified name ->n# */
+
+#define AA_X_UNSAFE		0x1000
+#define AA_X_CHILD		0x2000	/* make >AA_X_NONE apply to children */
+#define AA_X_INHERIT		0x4000
+#define AA_X_UNCONFINED		0x8000
+
+/* need to make conditional which ones are being set */
+struct path_cond {
+	kuid_t uid;
+	umode_t mode;
+};
+
+#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
+
+/* FIXME: split perms from dfa and match this to description
+ *        also add delegation info.
+ */
+static inline u16 dfa_map_xindex(u16 mask)
+{
+	u16 old_index = (mask >> 10) & 0xf;
+	u16 index = 0;
+
+	if (mask & 0x100)
+		index |= AA_X_UNSAFE;
+	if (mask & 0x200)
+		index |= AA_X_INHERIT;
+	if (mask & 0x80)
+		index |= AA_X_UNCONFINED;
+
+	if (old_index == 1) {
+		index |= AA_X_UNCONFINED;
+	} else if (old_index == 2) {
+		index |= AA_X_NAME;
+	} else if (old_index == 3) {
+		index |= AA_X_NAME | AA_X_CHILD;
+	} else if (old_index) {
+		index |= AA_X_TABLE;
+		index |= old_index - 4;
+	}
+
+	return index;
+}
+
+/*
+ * map old dfa inline permissions to new format
+ */
+#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) | \
+				    ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
+#define dfa_user_xbits(dfa, state) (((ACCEPT_TABLE(dfa)[state]) >> 7) & 0x7f)
+#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
+#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
+#define dfa_user_xindex(dfa, state) \
+	(dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
+
+#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
+				      0x7f) |				\
+				     ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
+#define dfa_other_xbits(dfa, state) \
+	((((ACCEPT_TABLE(dfa)[state]) >> 7) >> 14) & 0x7f)
+#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
+#define dfa_other_quiet(dfa, state) \
+	((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
+#define dfa_other_xindex(dfa, state) \
+	dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
+
+int aa_audit_file(struct aa_profile *profile, struct aa_perms *perms,
+		  const char *op, u32 request, const char *name,
+		  const char *target, struct aa_label *tlabel, kuid_t ouid,
+		  const char *info, int error);
+
+/**
+ * struct aa_file_rules - components used for file rule permissions
+ * @dfa: dfa to match path names and conditionals against
+ * @perms: permission table indexed by the matched state accept entry of @dfa
+ * @trans: transition table for indexed by named x transitions
+ *
+ * File permission are determined by matching a path against @dfa and
+ * then using the value of the accept entry for the matching state as
+ * an index into @perms.  If a named exec transition is required it is
+ * looked up in the transition table.
+ */
+struct aa_file_rules {
+	unsigned int start;
+	struct aa_dfa *dfa;
+	/* struct perms perms; */
+	struct aa_domain trans;
+	/* TODO: add delegate table */
+};
+
+struct aa_perms aa_compute_fperms(struct aa_dfa *dfa, unsigned int state,
+				    struct path_cond *cond);
+unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
+			  const char *name, struct path_cond *cond,
+			  struct aa_perms *perms);
+
+int __aa_path_perm(const char *op, struct aa_profile *profile,
+		   const char *name, u32 request, struct path_cond *cond,
+		   int flags, struct aa_perms *perms);
+int aa_path_perm(const char *op, struct aa_label *label,
+		 const struct path *path, int flags, u32 request,
+		 struct path_cond *cond);
+
+int aa_path_link(struct aa_label *label, struct dentry *old_dentry,
+		 const struct path *new_dir, struct dentry *new_dentry);
+
+int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
+		 u32 request, bool in_atomic);
+
+void aa_inherit_files(const struct cred *cred, struct files_struct *files);
+
+static inline void aa_free_file_rules(struct aa_file_rules *rules)
+{
+	aa_put_dfa(rules->dfa);
+	aa_free_domain_entries(&rules->trans);
+}
+
+/**
+ * aa_map_file_perms - map file flags to AppArmor permissions
+ * @file: open file to map flags to AppArmor permissions
+ *
+ * Returns: apparmor permission set for the file
+ */
+static inline u32 aa_map_file_to_perms(struct file *file)
+{
+	int flags = file->f_flags;
+	u32 perms = 0;
+
+	if (file->f_mode & FMODE_WRITE)
+		perms |= MAY_WRITE;
+	if (file->f_mode & FMODE_READ)
+		perms |= MAY_READ;
+
+	if ((flags & O_APPEND) && (perms & MAY_WRITE))
+		perms = (perms & ~MAY_WRITE) | MAY_APPEND;
+	/* trunc implies write permission */
+	if (flags & O_TRUNC)
+		perms |= MAY_WRITE;
+	if (flags & O_CREAT)
+		perms |= AA_MAY_CREATE;
+
+	return perms;
+}
+
+#endif /* __AA_FILE_H */