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-rw-r--r--security/apparmor/include/lib.h298
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diff --git a/security/apparmor/include/lib.h b/security/apparmor/include/lib.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor lib definitions
+ *
+ * 2017 Canonical Ltd.
+ */
+
+#ifndef __AA_LIB_H
+#define __AA_LIB_H
+
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/lsm_hooks.h>
+
+#include "match.h"
+
+/*
+ * DEBUG remains global (no per profile flag) since it is mostly used in sysctl
+ * which is not related to profile accesses.
+ */
+
+#define DEBUG_ON (aa_g_debug)
+/*
+ * split individual debug cases out in preparation for finer grained
+ * debug controls in the future.
+ */
+#define AA_DEBUG_LABEL DEBUG_ON
+#define dbg_printk(__fmt, __args...) pr_debug(__fmt, ##__args)
+#define AA_DEBUG(fmt, args...) \
+ do { \
+ if (DEBUG_ON) \
+ pr_debug_ratelimited("AppArmor: " fmt, ##args); \
+ } while (0)
+
+#define AA_WARN(X) WARN((X), "APPARMOR WARN %s: %s\n", __func__, #X)
+
+#define AA_BUG(X, args...) \
+ do { \
+ _Pragma("GCC diagnostic ignored \"-Wformat-zero-length\""); \
+ AA_BUG_FMT((X), "" args); \
+ _Pragma("GCC diagnostic warning \"-Wformat-zero-length\""); \
+ } while (0)
+#ifdef CONFIG_SECURITY_APPARMOR_DEBUG_ASSERTS
+#define AA_BUG_FMT(X, fmt, args...) \
+ WARN((X), "AppArmor WARN %s: (" #X "): " fmt, __func__, ##args)
+#else
+#define AA_BUG_FMT(X, fmt, args...) no_printk(fmt, ##args)
+#endif
+
+#define AA_ERROR(fmt, args...) \
+ pr_err_ratelimited("AppArmor: " fmt, ##args)
+
+/* Flag indicating whether initialization completed */
+extern int apparmor_initialized;
+
+/* fn's in lib */
+const char *skipn_spaces(const char *str, size_t n);
+char *aa_split_fqname(char *args, char **ns_name);
+const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name,
+ size_t *ns_len);
+void aa_info_message(const char *str);
+
+/* Security blob offsets */
+extern struct lsm_blob_sizes apparmor_blob_sizes;
+
+/**
+ * aa_strneq - compare null terminated @str to a non null terminated substring
+ * @str: a null terminated string
+ * @sub: a substring, not necessarily null terminated
+ * @len: length of @sub to compare
+ *
+ * The @str string must be full consumed for this to be considered a match
+ */
+static inline bool aa_strneq(const char *str, const char *sub, int len)
+{
+ return !strncmp(str, sub, len) && !str[len];
+}
+
+/**
+ * aa_dfa_null_transition - step to next state after null character
+ * @dfa: the dfa to match against
+ * @start: the state of the dfa to start matching in
+ *
+ * aa_dfa_null_transition transitions to the next state after a null
+ * character which is not used in standard matching and is only
+ * used to separate pairs.
+ */
+static inline unsigned int aa_dfa_null_transition(struct aa_dfa *dfa,
+ unsigned int start)
+{
+ /* the null transition only needs the string's null terminator byte */
+ return aa_dfa_next(dfa, start, 0);
+}
+
+static inline bool path_mediated_fs(struct dentry *dentry)
+{
+ return !(dentry->d_sb->s_flags & SB_NOUSER);
+}
+
+
+struct counted_str {
+ struct kref count;
+ char name[];
+};
+
+#define str_to_counted(str) \
+ ((struct counted_str *)(str - offsetof(struct counted_str, name)))
+
+#define __counted /* atm just a notation */
+
+void aa_str_kref(struct kref *kref);
+char *aa_str_alloc(int size, gfp_t gfp);
+
+
+static inline __counted char *aa_get_str(__counted char *str)
+{
+ if (str)
+ kref_get(&(str_to_counted(str)->count));
+
+ return str;
+}
+
+static inline void aa_put_str(__counted char *str)
+{
+ if (str)
+ kref_put(&str_to_counted(str)->count, aa_str_kref);
+}
+
+
+/* struct aa_policy - common part of both namespaces and profiles
+ * @name: name of the object
+ * @hname - The hierarchical name
+ * @list: list policy object is on
+ * @profiles: head of the profiles list contained in the object
+ */
+struct aa_policy {
+ const char *name;
+ __counted char *hname;
+ struct list_head list;
+ struct list_head profiles;
+};
+
+/**
+ * basename - find the last component of an hname
+ * @name: hname to find the base profile name component of (NOT NULL)
+ *
+ * Returns: the tail (base profile name) name component of an hname
+ */
+static inline const char *basename(const char *hname)
+{
+ char *split;
+
+ hname = strim((char *)hname);
+ for (split = strstr(hname, "//"); split; split = strstr(hname, "//"))
+ hname = split + 2;
+
+ return hname;
+}
+
+/**
+ * __policy_find - find a policy by @name on a policy list
+ * @head: list to search (NOT NULL)
+ * @name: name to search for (NOT NULL)
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy that match @name or NULL if not found
+ */
+static inline struct aa_policy *__policy_find(struct list_head *head,
+ const char *name)
+{
+ struct aa_policy *policy;
+
+ list_for_each_entry_rcu(policy, head, list) {
+ if (!strcmp(policy->name, name))
+ return policy;
+ }
+ return NULL;
+}
+
+/**
+ * __policy_strn_find - find a policy that's name matches @len chars of @str
+ * @head: list to search (NOT NULL)
+ * @str: string to search for (NOT NULL)
+ * @len: length of match required
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy that match @str or NULL if not found
+ *
+ * if @len == strlen(@strlen) then this is equiv to __policy_find
+ * other wise it allows searching for policy by a partial match of name
+ */
+static inline struct aa_policy *__policy_strn_find(struct list_head *head,
+ const char *str, int len)
+{
+ struct aa_policy *policy;
+
+ list_for_each_entry_rcu(policy, head, list) {
+ if (aa_strneq(policy->name, str, len))
+ return policy;
+ }
+
+ return NULL;
+}
+
+bool aa_policy_init(struct aa_policy *policy, const char *prefix,
+ const char *name, gfp_t gfp);
+void aa_policy_destroy(struct aa_policy *policy);
+
+
+/*
+ * fn_label_build - abstract out the build of a label transition
+ * @L: label the transition is being computed for
+ * @P: profile parameter derived from L by this macro, can be passed to FN
+ * @GFP: memory allocation type to use
+ * @FN: fn to call for each profile transition. @P is set to the profile
+ *
+ * Returns: new label on success
+ * ERR_PTR if build @FN fails
+ * NULL if label_build fails due to low memory conditions
+ *
+ * @FN must return a label or ERR_PTR on failure. NULL is not allowed
+ */
+#define fn_label_build(L, P, GFP, FN) \
+({ \
+ __label__ __cleanup, __done; \
+ struct aa_label *__new_; \
+ \
+ if ((L)->size > 1) { \
+ /* TODO: add cache of transitions already done */ \
+ struct label_it __i; \
+ int __j, __k, __count; \
+ DEFINE_VEC(label, __lvec); \
+ DEFINE_VEC(profile, __pvec); \
+ if (vec_setup(label, __lvec, (L)->size, (GFP))) { \
+ __new_ = NULL; \
+ goto __done; \
+ } \
+ __j = 0; \
+ label_for_each(__i, (L), (P)) { \
+ __new_ = (FN); \
+ AA_BUG(!__new_); \
+ if (IS_ERR(__new_)) \
+ goto __cleanup; \
+ __lvec[__j++] = __new_; \
+ } \
+ for (__j = __count = 0; __j < (L)->size; __j++) \
+ __count += __lvec[__j]->size; \
+ if (!vec_setup(profile, __pvec, __count, (GFP))) { \
+ for (__j = __k = 0; __j < (L)->size; __j++) { \
+ label_for_each(__i, __lvec[__j], (P)) \
+ __pvec[__k++] = aa_get_profile(P); \
+ } \
+ __count -= aa_vec_unique(__pvec, __count, 0); \
+ if (__count > 1) { \
+ __new_ = aa_vec_find_or_create_label(__pvec,\
+ __count, (GFP)); \
+ /* only fails if out of Mem */ \
+ if (!__new_) \
+ __new_ = NULL; \
+ } else \
+ __new_ = aa_get_label(&__pvec[0]->label); \
+ vec_cleanup(profile, __pvec, __count); \
+ } else \
+ __new_ = NULL; \
+__cleanup: \
+ vec_cleanup(label, __lvec, (L)->size); \
+ } else { \
+ (P) = labels_profile(L); \
+ __new_ = (FN); \
+ } \
+__done: \
+ if (!__new_) \
+ AA_DEBUG("label build failed\n"); \
+ (__new_); \
+})
+
+
+#define __fn_build_in_ns(NS, P, NS_FN, OTHER_FN) \
+({ \
+ struct aa_label *__new; \
+ if ((P)->ns != (NS)) \
+ __new = (OTHER_FN); \
+ else \
+ __new = (NS_FN); \
+ (__new); \
+})
+
+#define fn_label_build_in_ns(L, P, GFP, NS_FN, OTHER_FN) \
+({ \
+ fn_label_build((L), (P), (GFP), \
+ __fn_build_in_ns(labels_ns(L), (P), (NS_FN), (OTHER_FN))); \
+})
+
+#endif /* __AA_LIB_H */