809 lines
19 KiB
C
809 lines
19 KiB
C
/*
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* AppArmor security module
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*
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* This file contains AppArmor functions for unpacking policy loaded from
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* userspace.
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*
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* Copyright (C) 1998-2008 Novell/SUSE
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* Copyright 2009-2010 Canonical Ltd.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, version 2 of the
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* License.
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*
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* AppArmor uses a serialized binary format for loading policy. To find
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* policy format documentation look in Documentation/security/apparmor.txt
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* All policy is validated before it is used.
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*/
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#include <asm/unaligned.h>
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#include <linux/ctype.h>
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#include <linux/errno.h>
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#include "include/apparmor.h"
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#include "include/audit.h"
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#include "include/context.h"
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#include "include/crypto.h"
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#include "include/match.h"
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#include "include/policy.h"
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#include "include/policy_unpack.h"
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/*
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* The AppArmor interface treats data as a type byte followed by the
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* actual data. The interface has the notion of a a named entry
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* which has a name (AA_NAME typecode followed by name string) followed by
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* the entries typecode and data. Named types allow for optional
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* elements and extensions to be added and tested for without breaking
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* backwards compatibility.
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*/
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enum aa_code {
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AA_U8,
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AA_U16,
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AA_U32,
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AA_U64,
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AA_NAME, /* same as string except it is items name */
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AA_STRING,
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AA_BLOB,
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AA_STRUCT,
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AA_STRUCTEND,
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AA_LIST,
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AA_LISTEND,
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AA_ARRAY,
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AA_ARRAYEND,
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};
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/*
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* aa_ext is the read of the buffer containing the serialized profile. The
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* data is copied into a kernel buffer in apparmorfs and then handed off to
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* the unpack routines.
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*/
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struct aa_ext {
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void *start;
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void *end;
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void *pos; /* pointer to current position in the buffer */
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u32 version;
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};
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/* audit callback for unpack fields */
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static void audit_cb(struct audit_buffer *ab, void *va)
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{
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struct common_audit_data *sa = va;
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if (sa->aad->iface.target) {
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struct aa_profile *name = sa->aad->iface.target;
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audit_log_format(ab, " name=");
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audit_log_untrustedstring(ab, name->base.hname);
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}
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if (sa->aad->iface.pos)
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audit_log_format(ab, " offset=%ld", sa->aad->iface.pos);
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}
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/**
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* audit_iface - do audit message for policy unpacking/load/replace/remove
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* @new: profile if it has been allocated (MAYBE NULL)
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* @name: name of the profile being manipulated (MAYBE NULL)
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* @info: any extra info about the failure (MAYBE NULL)
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* @e: buffer position info
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* @error: error code
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*
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* Returns: %0 or error
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*/
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static int audit_iface(struct aa_profile *new, const char *name,
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const char *info, struct aa_ext *e, int error)
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{
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struct aa_profile *profile = __aa_current_profile();
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struct common_audit_data sa;
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struct apparmor_audit_data aad = {0,};
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sa.type = LSM_AUDIT_DATA_NONE;
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sa.aad = &aad;
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if (e)
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aad.iface.pos = e->pos - e->start;
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aad.iface.target = new;
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aad.name = name;
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aad.info = info;
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aad.error = error;
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return aa_audit(AUDIT_APPARMOR_STATUS, profile, GFP_KERNEL, &sa,
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audit_cb);
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}
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/* test if read will be in packed data bounds */
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static bool inbounds(struct aa_ext *e, size_t size)
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{
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return (size <= e->end - e->pos);
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}
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/**
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* aa_u16_chunck - test and do bounds checking for a u16 size based chunk
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* @e: serialized data read head (NOT NULL)
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* @chunk: start address for chunk of data (NOT NULL)
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*
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* Returns: the size of chunk found with the read head at the end of the chunk.
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*/
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static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
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{
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size_t size = 0;
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if (!inbounds(e, sizeof(u16)))
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return 0;
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size = le16_to_cpu(get_unaligned((u16 *) e->pos));
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e->pos += sizeof(u16);
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if (!inbounds(e, size))
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return 0;
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*chunk = e->pos;
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e->pos += size;
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return size;
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}
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/* unpack control byte */
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static bool unpack_X(struct aa_ext *e, enum aa_code code)
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{
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if (!inbounds(e, 1))
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return 0;
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if (*(u8 *) e->pos != code)
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return 0;
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e->pos++;
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return 1;
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}
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/**
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* unpack_nameX - check is the next element is of type X with a name of @name
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* @e: serialized data extent information (NOT NULL)
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* @code: type code
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* @name: name to match to the serialized element. (MAYBE NULL)
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*
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* check that the next serialized data element is of type X and has a tag
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* name @name. If @name is specified then there must be a matching
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* name element in the stream. If @name is NULL any name element will be
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* skipped and only the typecode will be tested.
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*
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* Returns 1 on success (both type code and name tests match) and the read
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* head is advanced past the headers
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*
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* Returns: 0 if either match fails, the read head does not move
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*/
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static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
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{
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/*
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* May need to reset pos if name or type doesn't match
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*/
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void *pos = e->pos;
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/*
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* Check for presence of a tagname, and if present name size
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* AA_NAME tag value is a u16.
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*/
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if (unpack_X(e, AA_NAME)) {
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char *tag = NULL;
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size_t size = unpack_u16_chunk(e, &tag);
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/* if a name is specified it must match. otherwise skip tag */
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if (name && (!size || strcmp(name, tag)))
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goto fail;
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} else if (name) {
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/* if a name is specified and there is no name tag fail */
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goto fail;
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}
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/* now check if type code matches */
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if (unpack_X(e, code))
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return 1;
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fail:
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e->pos = pos;
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return 0;
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}
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static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
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{
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if (unpack_nameX(e, AA_U32, name)) {
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if (!inbounds(e, sizeof(u32)))
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return 0;
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if (data)
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*data = le32_to_cpu(get_unaligned((u32 *) e->pos));
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e->pos += sizeof(u32);
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return 1;
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}
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return 0;
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}
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static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
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{
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if (unpack_nameX(e, AA_U64, name)) {
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if (!inbounds(e, sizeof(u64)))
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return 0;
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if (data)
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*data = le64_to_cpu(get_unaligned((u64 *) e->pos));
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e->pos += sizeof(u64);
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return 1;
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}
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return 0;
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}
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static size_t unpack_array(struct aa_ext *e, const char *name)
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{
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if (unpack_nameX(e, AA_ARRAY, name)) {
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int size;
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if (!inbounds(e, sizeof(u16)))
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return 0;
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size = (int)le16_to_cpu(get_unaligned((u16 *) e->pos));
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e->pos += sizeof(u16);
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return size;
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}
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return 0;
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}
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static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
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{
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if (unpack_nameX(e, AA_BLOB, name)) {
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u32 size;
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if (!inbounds(e, sizeof(u32)))
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return 0;
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size = le32_to_cpu(get_unaligned((u32 *) e->pos));
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e->pos += sizeof(u32);
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if (inbounds(e, (size_t) size)) {
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*blob = e->pos;
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e->pos += size;
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return size;
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}
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}
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return 0;
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}
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static int unpack_str(struct aa_ext *e, const char **string, const char *name)
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{
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char *src_str;
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size_t size = 0;
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void *pos = e->pos;
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*string = NULL;
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if (unpack_nameX(e, AA_STRING, name)) {
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size = unpack_u16_chunk(e, &src_str);
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if (size) {
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/* strings are null terminated, length is size - 1 */
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if (src_str[size - 1] != 0)
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goto fail;
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*string = src_str;
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}
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}
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return size;
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fail:
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e->pos = pos;
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return 0;
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}
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static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
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{
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const char *tmp;
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void *pos = e->pos;
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int res = unpack_str(e, &tmp, name);
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*string = NULL;
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if (!res)
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return 0;
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*string = kmemdup(tmp, res, GFP_KERNEL);
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if (!*string) {
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e->pos = pos;
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return 0;
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}
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return res;
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}
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#define DFA_VALID_PERM_MASK 0xffffffff
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#define DFA_VALID_PERM2_MASK 0xffffffff
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/**
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* verify_accept - verify the accept tables of a dfa
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* @dfa: dfa to verify accept tables of (NOT NULL)
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* @flags: flags governing dfa
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*
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* Returns: 1 if valid accept tables else 0 if error
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*/
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static bool verify_accept(struct aa_dfa *dfa, int flags)
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{
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int i;
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/* verify accept permissions */
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for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
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int mode = ACCEPT_TABLE(dfa)[i];
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if (mode & ~DFA_VALID_PERM_MASK)
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return 0;
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if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
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return 0;
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}
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return 1;
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}
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/**
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* unpack_dfa - unpack a file rule dfa
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* @e: serialized data extent information (NOT NULL)
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*
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* returns dfa or ERR_PTR or NULL if no dfa
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*/
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static struct aa_dfa *unpack_dfa(struct aa_ext *e)
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{
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char *blob = NULL;
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size_t size;
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struct aa_dfa *dfa = NULL;
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size = unpack_blob(e, &blob, "aadfa");
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if (size) {
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/*
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* The dfa is aligned with in the blob to 8 bytes
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* from the beginning of the stream.
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* alignment adjust needed by dfa unpack
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*/
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size_t sz = blob - (char *) e->start -
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((e->pos - e->start) & 7);
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size_t pad = ALIGN(sz, 8) - sz;
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int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
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TO_ACCEPT2_FLAG(YYTD_DATA32);
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if (aa_g_paranoid_load)
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flags |= DFA_FLAG_VERIFY_STATES;
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dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
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if (IS_ERR(dfa))
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return dfa;
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if (!verify_accept(dfa, flags))
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goto fail;
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}
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return dfa;
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fail:
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aa_put_dfa(dfa);
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return ERR_PTR(-EPROTO);
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}
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/**
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* unpack_trans_table - unpack a profile transition table
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* @e: serialized data extent information (NOT NULL)
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* @profile: profile to add the accept table to (NOT NULL)
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*
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* Returns: 1 if table successfully unpacked
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*/
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static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
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{
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void *pos = e->pos;
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/* exec table is optional */
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if (unpack_nameX(e, AA_STRUCT, "xtable")) {
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int i, size;
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size = unpack_array(e, NULL);
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/* currently 4 exec bits and entries 0-3 are reserved iupcx */
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if (size > 16 - 4)
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goto fail;
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profile->file.trans.table = kzalloc(sizeof(char *) * size,
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GFP_KERNEL);
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if (!profile->file.trans.table)
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goto fail;
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profile->file.trans.size = size;
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for (i = 0; i < size; i++) {
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char *str;
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int c, j, size2 = unpack_strdup(e, &str, NULL);
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/* unpack_strdup verifies that the last character is
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* null termination byte.
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*/
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if (!size2)
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goto fail;
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profile->file.trans.table[i] = str;
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/* verify that name doesn't start with space */
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if (isspace(*str))
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goto fail;
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/* count internal # of internal \0 */
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for (c = j = 0; j < size2 - 2; j++) {
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if (!str[j])
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c++;
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}
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if (*str == ':') {
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/* beginning with : requires an embedded \0,
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* verify that exactly 1 internal \0 exists
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* trailing \0 already verified by unpack_strdup
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*/
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if (c != 1)
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goto fail;
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/* first character after : must be valid */
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if (!str[1])
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goto fail;
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} else if (c)
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/* fail - all other cases with embedded \0 */
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goto fail;
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}
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if (!unpack_nameX(e, AA_ARRAYEND, NULL))
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goto fail;
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if (!unpack_nameX(e, AA_STRUCTEND, NULL))
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goto fail;
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}
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return 1;
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fail:
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aa_free_domain_entries(&profile->file.trans);
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e->pos = pos;
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return 0;
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}
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static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
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{
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void *pos = e->pos;
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/* rlimits are optional */
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if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
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int i, size;
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u32 tmp = 0;
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if (!unpack_u32(e, &tmp, NULL))
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goto fail;
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profile->rlimits.mask = tmp;
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size = unpack_array(e, NULL);
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if (size > RLIM_NLIMITS)
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goto fail;
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for (i = 0; i < size; i++) {
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u64 tmp2 = 0;
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int a = aa_map_resource(i);
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if (!unpack_u64(e, &tmp2, NULL))
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goto fail;
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profile->rlimits.limits[a].rlim_max = tmp2;
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}
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if (!unpack_nameX(e, AA_ARRAYEND, NULL))
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goto fail;
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if (!unpack_nameX(e, AA_STRUCTEND, NULL))
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goto fail;
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}
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return 1;
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fail:
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e->pos = pos;
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return 0;
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}
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/**
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* unpack_profile - unpack a serialized profile
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* @e: serialized data extent information (NOT NULL)
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*
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* NOTE: unpack profile sets audit struct if there is a failure
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*/
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static struct aa_profile *unpack_profile(struct aa_ext *e)
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{
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struct aa_profile *profile = NULL;
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const char *name = NULL;
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int i, error = -EPROTO;
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kernel_cap_t tmpcap;
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u32 tmp;
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/* check that we have the right struct being passed */
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if (!unpack_nameX(e, AA_STRUCT, "profile"))
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goto fail;
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if (!unpack_str(e, &name, NULL))
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goto fail;
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profile = aa_alloc_profile(name);
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if (!profile)
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return ERR_PTR(-ENOMEM);
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/* profile renaming is optional */
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(void) unpack_str(e, &profile->rename, "rename");
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/* attachment string is optional */
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(void) unpack_str(e, &profile->attach, "attach");
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/* xmatch is optional and may be NULL */
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profile->xmatch = unpack_dfa(e);
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if (IS_ERR(profile->xmatch)) {
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error = PTR_ERR(profile->xmatch);
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profile->xmatch = NULL;
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goto fail;
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}
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/* xmatch_len is not optional if xmatch is set */
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if (profile->xmatch) {
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if (!unpack_u32(e, &tmp, NULL))
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goto fail;
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profile->xmatch_len = tmp;
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}
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/* per profile debug flags (complain, audit) */
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if (!unpack_nameX(e, AA_STRUCT, "flags"))
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goto fail;
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if (!unpack_u32(e, &tmp, NULL))
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goto fail;
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if (tmp & PACKED_FLAG_HAT)
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profile->flags |= PFLAG_HAT;
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if (!unpack_u32(e, &tmp, NULL))
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goto fail;
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if (tmp == PACKED_MODE_COMPLAIN)
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profile->mode = APPARMOR_COMPLAIN;
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else if (tmp == PACKED_MODE_KILL)
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profile->mode = APPARMOR_KILL;
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else if (tmp == PACKED_MODE_UNCONFINED)
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profile->mode = APPARMOR_UNCONFINED;
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if (!unpack_u32(e, &tmp, NULL))
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goto fail;
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if (tmp)
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profile->audit = AUDIT_ALL;
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if (!unpack_nameX(e, AA_STRUCTEND, NULL))
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goto fail;
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/* path_flags is optional */
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if (unpack_u32(e, &profile->path_flags, "path_flags"))
|
|
profile->path_flags |= profile->flags & PFLAG_MEDIATE_DELETED;
|
|
else
|
|
/* set a default value if path_flags field is not present */
|
|
profile->path_flags = PFLAG_MEDIATE_DELETED;
|
|
|
|
if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &tmpcap.cap[0], NULL))
|
|
goto fail;
|
|
|
|
if (unpack_nameX(e, AA_STRUCT, "caps64")) {
|
|
/* optional upper half of 64 bit caps */
|
|
if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
|
|
goto fail;
|
|
if (!unpack_nameX(e, AA_STRUCTEND, NULL))
|
|
goto fail;
|
|
}
|
|
|
|
if (unpack_nameX(e, AA_STRUCT, "capsx")) {
|
|
/* optional extended caps mediation mask */
|
|
if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
|
|
goto fail;
|
|
if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
|
|
goto fail;
|
|
if (!unpack_nameX(e, AA_STRUCTEND, NULL))
|
|
goto fail;
|
|
}
|
|
|
|
if (!unpack_rlimits(e, profile))
|
|
goto fail;
|
|
|
|
if (unpack_nameX(e, AA_STRUCT, "policydb")) {
|
|
/* generic policy dfa - optional and may be NULL */
|
|
profile->policy.dfa = unpack_dfa(e);
|
|
if (IS_ERR(profile->policy.dfa)) {
|
|
error = PTR_ERR(profile->policy.dfa);
|
|
profile->policy.dfa = NULL;
|
|
goto fail;
|
|
} else if (!profile->policy.dfa) {
|
|
error = -EPROTO;
|
|
goto fail;
|
|
}
|
|
if (!unpack_u32(e, &profile->policy.start[0], "start"))
|
|
/* default start state */
|
|
profile->policy.start[0] = DFA_START;
|
|
/* setup class index */
|
|
for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
|
|
profile->policy.start[i] =
|
|
aa_dfa_next(profile->policy.dfa,
|
|
profile->policy.start[0],
|
|
i);
|
|
}
|
|
if (!unpack_nameX(e, AA_STRUCTEND, NULL))
|
|
goto fail;
|
|
}
|
|
|
|
/* get file rules */
|
|
profile->file.dfa = unpack_dfa(e);
|
|
if (IS_ERR(profile->file.dfa)) {
|
|
error = PTR_ERR(profile->file.dfa);
|
|
profile->file.dfa = NULL;
|
|
goto fail;
|
|
}
|
|
|
|
if (!unpack_u32(e, &profile->file.start, "dfa_start"))
|
|
/* default start state */
|
|
profile->file.start = DFA_START;
|
|
|
|
if (!unpack_trans_table(e, profile))
|
|
goto fail;
|
|
|
|
if (!unpack_nameX(e, AA_STRUCTEND, NULL))
|
|
goto fail;
|
|
|
|
return profile;
|
|
|
|
fail:
|
|
if (profile)
|
|
name = NULL;
|
|
else if (!name)
|
|
name = "unknown";
|
|
audit_iface(profile, name, "failed to unpack profile", e, error);
|
|
aa_free_profile(profile);
|
|
|
|
return ERR_PTR(error);
|
|
}
|
|
|
|
/**
|
|
* verify_head - unpack serialized stream header
|
|
* @e: serialized data read head (NOT NULL)
|
|
* @required: whether the header is required or optional
|
|
* @ns: Returns - namespace if one is specified else NULL (NOT NULL)
|
|
*
|
|
* Returns: error or 0 if header is good
|
|
*/
|
|
static int verify_header(struct aa_ext *e, int required, const char **ns)
|
|
{
|
|
int error = -EPROTONOSUPPORT;
|
|
const char *name = NULL;
|
|
*ns = NULL;
|
|
|
|
/* get the interface version */
|
|
if (!unpack_u32(e, &e->version, "version")) {
|
|
if (required) {
|
|
audit_iface(NULL, NULL, "invalid profile format", e,
|
|
error);
|
|
return error;
|
|
}
|
|
|
|
/* check that the interface version is currently supported */
|
|
if (e->version != 5) {
|
|
audit_iface(NULL, NULL, "unsupported interface version",
|
|
e, error);
|
|
return error;
|
|
}
|
|
}
|
|
|
|
|
|
/* read the namespace if present */
|
|
if (unpack_str(e, &name, "namespace")) {
|
|
if (*ns && strcmp(*ns, name))
|
|
audit_iface(NULL, NULL, "invalid ns change", e, error);
|
|
else if (!*ns)
|
|
*ns = name;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool verify_xindex(int xindex, int table_size)
|
|
{
|
|
int index, xtype;
|
|
xtype = xindex & AA_X_TYPE_MASK;
|
|
index = xindex & AA_X_INDEX_MASK;
|
|
if (xtype == AA_X_TABLE && index >= table_size)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
/* verify dfa xindexes are in range of transition tables */
|
|
static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
|
|
{
|
|
int i;
|
|
for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
|
|
if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
|
|
return 0;
|
|
if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* verify_profile - Do post unpack analysis to verify profile consistency
|
|
* @profile: profile to verify (NOT NULL)
|
|
*
|
|
* Returns: 0 if passes verification else error
|
|
*/
|
|
static int verify_profile(struct aa_profile *profile)
|
|
{
|
|
if (aa_g_paranoid_load) {
|
|
if (profile->file.dfa &&
|
|
!verify_dfa_xindex(profile->file.dfa,
|
|
profile->file.trans.size)) {
|
|
audit_iface(profile, NULL, "Invalid named transition",
|
|
NULL, -EPROTO);
|
|
return -EPROTO;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void aa_load_ent_free(struct aa_load_ent *ent)
|
|
{
|
|
if (ent) {
|
|
aa_put_profile(ent->rename);
|
|
aa_put_profile(ent->old);
|
|
aa_put_profile(ent->new);
|
|
kzfree(ent);
|
|
}
|
|
}
|
|
|
|
struct aa_load_ent *aa_load_ent_alloc(void)
|
|
{
|
|
struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
|
|
if (ent)
|
|
INIT_LIST_HEAD(&ent->list);
|
|
return ent;
|
|
}
|
|
|
|
/**
|
|
* aa_unpack - unpack packed binary profile(s) data loaded from user space
|
|
* @udata: user data copied to kmem (NOT NULL)
|
|
* @size: the size of the user data
|
|
* @lh: list to place unpacked profiles in a aa_repl_ws
|
|
* @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
|
|
*
|
|
* Unpack user data and return refcounted allocated profile(s) stored in
|
|
* @lh in order of discovery, with the list chain stored in base.list
|
|
* or error
|
|
*
|
|
* Returns: profile(s) on @lh else error pointer if fails to unpack
|
|
*/
|
|
int aa_unpack(void *udata, size_t size, struct list_head *lh, const char **ns)
|
|
{
|
|
struct aa_load_ent *tmp, *ent;
|
|
struct aa_profile *profile = NULL;
|
|
int error;
|
|
struct aa_ext e = {
|
|
.start = udata,
|
|
.end = udata + size,
|
|
.pos = udata,
|
|
};
|
|
|
|
*ns = NULL;
|
|
while (e.pos < e.end) {
|
|
void *start;
|
|
error = verify_header(&e, e.pos == e.start, ns);
|
|
if (error)
|
|
goto fail;
|
|
|
|
start = e.pos;
|
|
profile = unpack_profile(&e);
|
|
if (IS_ERR(profile)) {
|
|
error = PTR_ERR(profile);
|
|
goto fail;
|
|
}
|
|
|
|
error = verify_profile(profile);
|
|
if (error)
|
|
goto fail_profile;
|
|
|
|
error = aa_calc_profile_hash(profile, e.version, start,
|
|
e.pos - start);
|
|
if (error)
|
|
goto fail_profile;
|
|
|
|
ent = aa_load_ent_alloc();
|
|
if (!ent) {
|
|
error = -ENOMEM;
|
|
goto fail_profile;
|
|
}
|
|
|
|
ent->new = profile;
|
|
list_add_tail(&ent->list, lh);
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail_profile:
|
|
aa_put_profile(profile);
|
|
|
|
fail:
|
|
list_for_each_entry_safe(ent, tmp, lh, list) {
|
|
list_del_init(&ent->list);
|
|
aa_load_ent_free(ent);
|
|
}
|
|
|
|
return error;
|
|
}
|