1 /* 2 * AppArmor security module 3 * 4 * This file contains AppArmor ipc mediation 5 * 6 * Copyright (C) 1998-2008 Novell/SUSE 7 * Copyright 2009-2010 Canonical Ltd. 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License as 11 * published by the Free Software Foundation, version 2 of the 12 * License. 13 */ 14 15 #include <linux/gfp.h> 16 #include <linux/ptrace.h> 17 18 #include "include/audit.h" 19 #include "include/capability.h" 20 #include "include/context.h" 21 #include "include/policy.h" 22 #include "include/ipc.h" 23 24 /* call back to audit ptrace fields */ 25 static void audit_cb(struct audit_buffer *ab, void *va) 26 { 27 struct common_audit_data *sa = va; 28 audit_log_format(ab, " peer="); 29 audit_log_untrustedstring(ab, aad(sa)->peer->base.hname); 30 } 31 32 /** 33 * aa_audit_ptrace - do auditing for ptrace 34 * @profile: profile being enforced (NOT NULL) 35 * @target: profile being traced (NOT NULL) 36 * @error: error condition 37 * 38 * Returns: %0 or error code 39 */ 40 static int aa_audit_ptrace(struct aa_profile *profile, 41 struct aa_profile *target, int error) 42 { 43 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_PTRACE); 44 45 aad(&sa)->peer = target; 46 aad(&sa)->error = error; 47 48 return aa_audit(AUDIT_APPARMOR_AUTO, profile, &sa, audit_cb); 49 } 50 51 /** 52 * aa_may_ptrace - test if tracer task can trace the tracee 53 * @tracer: profile of the task doing the tracing (NOT NULL) 54 * @tracee: task to be traced 55 * @mode: whether PTRACE_MODE_READ || PTRACE_MODE_ATTACH 56 * 57 * Returns: %0 else error code if permission denied or error 58 */ 59 int aa_may_ptrace(struct aa_profile *tracer, struct aa_profile *tracee, 60 unsigned int mode) 61 { 62 /* TODO: currently only based on capability, not extended ptrace 63 * rules, 64 * Test mode for PTRACE_MODE_READ || PTRACE_MODE_ATTACH 65 */ 66 67 if (unconfined(tracer) || tracer == tracee) 68 return 0; 69 /* log this capability request */ 70 return aa_capable(tracer, CAP_SYS_PTRACE, 1); 71 } 72 73 /** 74 * aa_ptrace - do ptrace permission check and auditing 75 * @tracer: task doing the tracing (NOT NULL) 76 * @tracee: task being traced (NOT NULL) 77 * @mode: ptrace mode either PTRACE_MODE_READ || PTRACE_MODE_ATTACH 78 * 79 * Returns: %0 else error code if permission denied or error 80 */ 81 int aa_ptrace(struct task_struct *tracer, struct task_struct *tracee, 82 unsigned int mode) 83 { 84 /* 85 * tracer can ptrace tracee when 86 * - tracer is unconfined || 87 * - tracer is in complain mode 88 * - tracer has rules allowing it to trace tracee currently this is: 89 * - confined by the same profile || 90 * - tracer profile has CAP_SYS_PTRACE 91 */ 92 93 struct aa_profile *tracer_p = aa_get_task_profile(tracer); 94 int error = 0; 95 96 if (!unconfined(tracer_p)) { 97 struct aa_profile *tracee_p = aa_get_task_profile(tracee); 98 99 error = aa_may_ptrace(tracer_p, tracee_p, mode); 100 error = aa_audit_ptrace(tracer_p, tracee_p, error); 101 102 aa_put_profile(tracee_p); 103 } 104 aa_put_profile(tracer_p); 105 106 return error; 107 } 108