// SPDX-License-Identifier: GPL-2.0-only/* * AppArmor security module * * This file contains AppArmor ipc mediation * * Copyright (C) 1998-2008 Novell/SUSE * Copyright 2009-2017 Canonical Ltd. */ #include <linux/gfp.h>#include <linux/ptrace.h> #include "include/audit.h"#include "include/capability.h"#include "include/cred.h"#include "include/policy.h"#include "include/ipc.h"#include "include/sig_names.h" /** * audit_ptrace_mask - convert mask to permission string * @mask: permission mask to convert * * Returns: pointer to static string */static const char *audit_ptrace_mask(u32 mask){	switch (mask) {	case MAY_READ:		return "read";	case MAY_WRITE:		return "trace";	case AA_MAY_BE_READ:		return "readby";	case AA_MAY_BE_TRACED:		return "tracedby";	}	return "";} /* call back to audit ptrace fields */static void audit_ptrace_cb(struct audit_buffer *ab, void *va){	struct common_audit_data *sa = va; 	if (aad(sa)->request & AA_PTRACE_PERM_MASK) {		audit_log_format(ab, " requested_mask=\"%s\"",				 audit_ptrace_mask(aad(sa)->request)); 		if (aad(sa)->denied & AA_PTRACE_PERM_MASK) {			audit_log_format(ab, " denied_mask=\"%s\"",					 audit_ptrace_mask(aad(sa)->denied));		}	}	audit_log_format(ab, " peer=");	aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,			FLAGS_NONE, GFP_ATOMIC);} /* assumes check for PROFILE_MEDIATES is already done *//* TODO: conditionals */static int profile_ptrace_perm(struct aa_profile *profile,			     struct aa_label *peer, u32 request,			     struct common_audit_data *sa){	struct aa_perms perms = { }; 	aad(sa)->peer = peer;	aa_profile_match_label(profile, peer, AA_CLASS_PTRACE, request,			       &perms);	aa_apply_modes_to_perms(profile, &perms);	return aa_check_perms(profile, &perms, request, sa, audit_ptrace_cb);} static int profile_tracee_perm(struct aa_profile *tracee,			       struct aa_label *tracer, u32 request,			       struct common_audit_data *sa){	if (profile_unconfined(tracee) || unconfined(tracer) ||	    !PROFILE_MEDIATES(tracee, AA_CLASS_PTRACE))		return 0; 	return profile_ptrace_perm(tracee, tracer, request, sa);} static int profile_tracer_perm(struct aa_profile *tracer,			       struct aa_label *tracee, u32 request,			       struct common_audit_data *sa){	if (profile_unconfined(tracer))		return 0; 	if (PROFILE_MEDIATES(tracer, AA_CLASS_PTRACE))		return profile_ptrace_perm(tracer, tracee, request, sa); 	/* profile uses the old style capability check for ptrace */	if (&tracer->label == tracee)		return 0; 	aad(sa)->label = &tracer->label;	aad(sa)->peer = tracee;	aad(sa)->request = 0;	aad(sa)->error = aa_capable(&tracer->label, CAP_SYS_PTRACE,				    CAP_OPT_NONE); 	return aa_audit(AUDIT_APPARMOR_AUTO, tracer, sa, audit_ptrace_cb);} /** * aa_may_ptrace - test if tracer task can trace the tracee * @tracer: label of the task doing the tracing  (NOT NULL) * @tracee: task label to be traced * @request: permission request * * Returns: %0 else error code if permission denied or error */int aa_may_ptrace(struct aa_label *tracer, struct aa_label *tracee,		  u32 request){	struct aa_profile *profile;	u32 xrequest = request << PTRACE_PERM_SHIFT;	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_PTRACE); 	return xcheck_labels(tracer, tracee, profile,			profile_tracer_perm(profile, tracee, request, &sa),			profile_tracee_perm(profile, tracer, xrequest, &sa));}  static inline int map_signal_num(int sig){	if (sig > SIGRTMAX)		return SIGUNKNOWN;	else if (sig >= SIGRTMIN)		return sig - SIGRTMIN + SIGRT_BASE;	else if (sig < MAXMAPPED_SIG)		return sig_map[sig];	return SIGUNKNOWN;} /** * audit_signal_mask - convert mask to permission string * @mask: permission mask to convert * * Returns: pointer to static string */static const char *audit_signal_mask(u32 mask){	if (mask & MAY_READ)		return "receive";	if (mask & MAY_WRITE)		return "send";	return "";} /** * audit_cb - call back for signal specific audit fields * @ab: audit_buffer  (NOT NULL) * @va: audit struct to audit values of  (NOT NULL) */static void audit_signal_cb(struct audit_buffer *ab, void *va){	struct common_audit_data *sa = va; 	if (aad(sa)->request & AA_SIGNAL_PERM_MASK) {		audit_log_format(ab, " requested_mask=\"%s\"",				 audit_signal_mask(aad(sa)->request));		if (aad(sa)->denied & AA_SIGNAL_PERM_MASK) {			audit_log_format(ab, " denied_mask=\"%s\"",					 audit_signal_mask(aad(sa)->denied));		}	}	if (aad(sa)->signal == SIGUNKNOWN)		audit_log_format(ab, "signal=unknown(%d)",				 aad(sa)->unmappedsig);	else if (aad(sa)->signal < MAXMAPPED_SIGNAME)		audit_log_format(ab, " signal=%s", sig_names[aad(sa)->signal]);	else		audit_log_format(ab, " signal=rtmin+%d",				 aad(sa)->signal - SIGRT_BASE);	audit_log_format(ab, " peer=");	aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,			FLAGS_NONE, GFP_ATOMIC);} static int profile_signal_perm(struct aa_profile *profile,			       struct aa_label *peer, u32 request,			       struct common_audit_data *sa){	struct aa_perms perms;	unsigned int state; 	if (profile_unconfined(profile) ||	    !PROFILE_MEDIATES(profile, AA_CLASS_SIGNAL))		return 0; 	aad(sa)->peer = peer;	/* TODO: secondary cache check <profile, profile, perm> */	state = aa_dfa_next(profile->policy.dfa,			    profile->policy.start[AA_CLASS_SIGNAL],			    aad(sa)->signal);	aa_label_match(profile, peer, state, false, request, &perms);	aa_apply_modes_to_perms(profile, &perms);	return aa_check_perms(profile, &perms, request, sa, audit_signal_cb);} int aa_may_signal(struct aa_label *sender, struct aa_label *target, int sig){	struct aa_profile *profile;	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SIGNAL); 	aad(&sa)->signal = map_signal_num(sig);	aad(&sa)->unmappedsig = sig;	return xcheck_labels(sender, target, profile,			profile_signal_perm(profile, target, MAY_WRITE, &sa),			profile_signal_perm(profile, sender, MAY_READ, &sa));}