diff options
| -rw-r--r-- | security/apparmor/capability.c | 141 | ||||
| -rw-r--r-- | security/apparmor/include/capability.h | 45 | ||||
| -rw-r--r-- | security/apparmor/include/ipc.h | 28 | ||||
| -rw-r--r-- | security/apparmor/include/resource.h | 46 | ||||
| -rw-r--r-- | security/apparmor/ipc.c | 114 | ||||
| -rw-r--r-- | security/apparmor/resource.c | 134 |
6 files changed, 508 insertions, 0 deletions
diff --git a/security/apparmor/capability.c b/security/apparmor/capability.c new file mode 100644 index 000000000000..9982c48def4e --- /dev/null +++ b/security/apparmor/capability.c @@ -0,0 +1,141 @@ +/* + * AppArmor security module + * + * This file contains AppArmor capability mediation functions + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include <linux/capability.h> +#include <linux/errno.h> +#include <linux/gfp.h> + +#include "include/apparmor.h" +#include "include/capability.h" +#include "include/context.h" +#include "include/policy.h" +#include "include/audit.h" + +/* + * Table of capability names: we generate it from capabilities.h. + */ +#include "capability_names.h" + +struct audit_cache { + struct aa_profile *profile; + kernel_cap_t caps; +}; + +static DEFINE_PER_CPU(struct audit_cache, audit_cache); + +/** + * audit_cb - call back for capability components of audit struct + * @ab - audit buffer (NOT NULL) + * @va - audit struct to audit data from (NOT NULL) + */ +static void audit_cb(struct audit_buffer *ab, void *va) +{ + struct common_audit_data *sa = va; + audit_log_format(ab, " capname="); + audit_log_untrustedstring(ab, capability_names[sa->u.cap]); +} + +/** + * audit_caps - audit a capability + * @profile: profile confining task (NOT NULL) + * @task: task capability test was performed against (NOT NULL) + * @cap: capability tested + * @error: error code returned by test + * + * Do auditing of capability and handle, audit/complain/kill modes switching + * and duplicate message elimination. + * + * Returns: 0 or sa->error on success, error code on failure + */ +static int audit_caps(struct aa_profile *profile, struct task_struct *task, + int cap, int error) +{ + struct audit_cache *ent; + int type = AUDIT_APPARMOR_AUTO; + struct common_audit_data sa; + COMMON_AUDIT_DATA_INIT(&sa, CAP); + sa.tsk = task; + sa.u.cap = cap; + sa.aad.op = OP_CAPABLE; + sa.aad.error = error; + + if (likely(!error)) { + /* test if auditing is being forced */ + if (likely((AUDIT_MODE(profile) != AUDIT_ALL) && + !cap_raised(profile->caps.audit, cap))) + return 0; + type = AUDIT_APPARMOR_AUDIT; + } else if (KILL_MODE(profile) || + cap_raised(profile->caps.kill, cap)) { + type = AUDIT_APPARMOR_KILL; + } else if (cap_raised(profile->caps.quiet, cap) && + AUDIT_MODE(profile) != AUDIT_NOQUIET && + AUDIT_MODE(profile) != AUDIT_ALL) { + /* quiet auditing */ + return error; + } + + /* Do simple duplicate message elimination */ + ent = &get_cpu_var(audit_cache); + if (profile == ent->profile && cap_raised(ent->caps, cap)) { + put_cpu_var(audit_cache); + if (COMPLAIN_MODE(profile)) + return complain_error(error); + return error; + } else { + aa_put_profile(ent->profile); + ent->profile = aa_get_profile(profile); + cap_raise(ent->caps, cap); + } + put_cpu_var(audit_cache); + + return aa_audit(type, profile, GFP_ATOMIC, &sa, audit_cb); +} + +/** + * profile_capable - test if profile allows use of capability @cap + * @profile: profile being enforced (NOT NULL, NOT unconfined) + * @cap: capability to test if allowed + * + * Returns: 0 if allowed else -EPERM + */ +static int profile_capable(struct aa_profile *profile, int cap) +{ + return cap_raised(profile->caps.allow, cap) ? 0 : -EPERM; +} + +/** + * aa_capable - test permission to use capability + * @task: task doing capability test against (NOT NULL) + * @profile: profile confining @task (NOT NULL) + * @cap: capability to be tested + * @audit: whether an audit record should be generated + * + * Look up capability in profile capability set. + * + * Returns: 0 on success, or else an error code. + */ +int aa_capable(struct task_struct *task, struct aa_profile *profile, int cap, + int audit) +{ + int error = profile_capable(profile, cap); + + if (!audit) { + if (COMPLAIN_MODE(profile)) + return complain_error(error); + return error; + } + + return audit_caps(profile, task, cap, error); +} diff --git a/security/apparmor/include/capability.h b/security/apparmor/include/capability.h new file mode 100644 index 000000000000..c24d2959ea02 --- /dev/null +++ b/security/apparmor/include/capability.h @@ -0,0 +1,45 @@ +/* + * AppArmor security module + * + * This file contains AppArmor capability mediation definitions. + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#ifndef __AA_CAPABILITY_H +#define __AA_CAPABILITY_H + +#include <linux/sched.h> + +struct aa_profile; + +/* aa_caps - confinement data for capabilities + * @allowed: capabilities mask + * @audit: caps that are to be audited + * @quiet: caps that should not be audited + * @kill: caps that when requested will result in the task being killed + * @extended: caps that are subject finer grained mediation + */ +struct aa_caps { + kernel_cap_t allow; + kernel_cap_t audit; + kernel_cap_t quiet; + kernel_cap_t kill; + kernel_cap_t extended; +}; + +int aa_capable(struct task_struct *task, struct aa_profile *profile, int cap, + int audit); + +static inline void aa_free_cap_rules(struct aa_caps *caps) +{ + /* NOP */ +} + +#endif /* __AA_CAPBILITY_H */ diff --git a/security/apparmor/include/ipc.h b/security/apparmor/include/ipc.h new file mode 100644 index 000000000000..aeda0fbc8b2f --- /dev/null +++ b/security/apparmor/include/ipc.h @@ -0,0 +1,28 @@ +/* + * AppArmor security module + * + * This file contains AppArmor ipc mediation function definitions. + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#ifndef __AA_IPC_H +#define __AA_IPC_H + +#include <linux/sched.h> + +struct aa_profile; + +int aa_may_ptrace(struct task_struct *tracer_task, struct aa_profile *tracer, + struct aa_profile *tracee, unsigned int mode); + +int aa_ptrace(struct task_struct *tracer, struct task_struct *tracee, + unsigned int mode); + +#endif /* __AA_IPC_H */ diff --git a/security/apparmor/include/resource.h b/security/apparmor/include/resource.h new file mode 100644 index 000000000000..3c88be946494 --- /dev/null +++ b/security/apparmor/include/resource.h @@ -0,0 +1,46 @@ +/* + * AppArmor security module + * + * This file contains AppArmor resource limits function definitions. + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#ifndef __AA_RESOURCE_H +#define __AA_RESOURCE_H + +#include <linux/resource.h> +#include <linux/sched.h> + +struct aa_profile; + +/* struct aa_rlimit - rlimit settings for the profile + * @mask: which hard limits to set + * @limits: rlimit values that override task limits + * + * AppArmor rlimits are used to set confined task rlimits. Only the + * limits specified in @mask will be controlled by apparmor. + */ +struct aa_rlimit { + unsigned int mask; + struct rlimit limits[RLIM_NLIMITS]; +}; + +int aa_map_resource(int resource); +int aa_task_setrlimit(struct aa_profile *profile, unsigned int resource, + struct rlimit *new_rlim); + +void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new); + +static inline void aa_free_rlimit_rules(struct aa_rlimit *rlims) +{ + /* NOP */ +} + +#endif /* __AA_RESOURCE_H */ diff --git a/security/apparmor/ipc.c b/security/apparmor/ipc.c new file mode 100644 index 000000000000..9013a78a1663 --- /dev/null +++ b/security/apparmor/ipc.c @@ -0,0 +1,114 @@ +/* + * AppArmor security module + * + * This file contains AppArmor ipc mediation + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include <linux/gfp.h> +#include <linux/ptrace.h> + +#include "include/audit.h" +#include "include/capability.h" +#include "include/context.h" +#include "include/policy.h" + +/* call back to audit ptrace fields */ +static void audit_cb(struct audit_buffer *ab, void *va) +{ + struct common_audit_data *sa = va; + audit_log_format(ab, " target="); + audit_log_untrustedstring(ab, sa->aad.target); +} + +/** + * aa_audit_ptrace - do auditing for ptrace + * @profile: profile being enforced (NOT NULL) + * @target: profile being traced (NOT NULL) + * @error: error condition + * + * Returns: %0 or error code + */ +static int aa_audit_ptrace(struct aa_profile *profile, + struct aa_profile *target, int error) +{ + struct common_audit_data sa; + COMMON_AUDIT_DATA_INIT(&sa, NONE); + sa.aad.op = OP_PTRACE; + sa.aad.target = target; + sa.aad.error = error; + + return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_ATOMIC, &sa, + audit_cb); +} + +/** + * aa_may_ptrace - test if tracer task can trace the tracee + * @tracer_task: task who will do the tracing (NOT NULL) + * @tracer: profile of the task doing the tracing (NOT NULL) + * @tracee: task to be traced + * @mode: whether PTRACE_MODE_READ || PTRACE_MODE_ATTACH + * + * Returns: %0 else error code if permission denied or error + */ +int aa_may_ptrace(struct task_struct *tracer_task, struct aa_profile *tracer, + struct aa_profile *tracee, unsigned int mode) +{ + /* TODO: currently only based on capability, not extended ptrace + * rules, + * Test mode for PTRACE_MODE_READ || PTRACE_MODE_ATTACH + */ + + if (unconfined(tracer) || tracer == tracee) + return 0; + /* log this capability request */ + return aa_capable(tracer_task, tracer, CAP_SYS_PTRACE, 1); +} + +/** + * aa_ptrace - do ptrace permission check and auditing + * @tracer: task doing the tracing (NOT NULL) + * @tracee: task being traced (NOT NULL) + * @mode: ptrace mode either PTRACE_MODE_READ || PTRACE_MODE_ATTACH + * + * Returns: %0 else error code if permission denied or error + */ +int aa_ptrace(struct task_struct *tracer, struct task_struct *tracee, + unsigned int mode) +{ + /* + * tracer can ptrace tracee when + * - tracer is unconfined || + * - tracer is in complain mode + * - tracer has rules allowing it to trace tracee currently this is: + * - confined by the same profile || + * - tracer profile has CAP_SYS_PTRACE + */ + + struct aa_profile *tracer_p; + /* cred released below */ + const struct cred *cred = get_task_cred(tracer); + int error = 0; + tracer_p = aa_cred_profile(cred); + + if (!unconfined(tracer_p)) { + /* lcred released below */ + struct cred *lcred = get_task_cred(tracee); + struct aa_profile *tracee_p = aa_cred_profile(lcred); + + error = aa_may_ptrace(tracer, tracer_p, tracee_p, mode); + error = aa_audit_ptrace(tracer_p, tracee_p, error); + + put_cred(lcred); + } + put_cred(cred); + + return error; +} diff --git a/security/apparmor/resource.c b/security/apparmor/resource.c new file mode 100644 index 000000000000..4a368f1fd36d --- /dev/null +++ b/security/apparmor/resource.c @@ -0,0 +1,134 @@ +/* + * AppArmor security module + * + * This file contains AppArmor resource mediation and attachment + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include <linux/audit.h> + +#include "include/audit.h" +#include "include/resource.h" +#include "include/policy.h" + +/* + * Table of rlimit names: we generate it from resource.h. + */ +#include "rlim_names.h" + +/* audit callback for resource specific fields */ +static void audit_cb(struct audit_buffer *ab, void *va) +{ + struct common_audit_data *sa = va; + + audit_log_format(ab, " rlimit=%s value=%lu", + rlim_names[sa->aad.rlim.rlim], sa->aad.rlim.max); +} + +/** + * audit_resource - audit setting resource limit + * @profile: profile being enforced (NOT NULL) + * @resoure: rlimit being auditing + * @value: value being set + * @error: error value + * + * Returns: 0 or sa->error else other error code on failure + */ +static int audit_resource(struct aa_profile *profile, unsigned int resource, + unsigned long value, int error) +{ + struct common_audit_data sa; + + COMMON_AUDIT_DATA_INIT(&sa, NONE); + sa.aad.op = OP_SETRLIMIT, + sa.aad.rlim.rlim = resource; + sa.aad.rlim.max = value; + sa.aad.error = error; + return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa, + audit_cb); +} + +/** + * aa_map_resouce - map compiled policy resource to internal # + * @resource: flattened policy resource number + * + * Returns: resource # for the current architecture. + * + * rlimit resource can vary based on architecture, map the compiled policy + * resource # to the internal representation for the architecture. + */ +int aa_map_resource(int resource) +{ + return rlim_map[resource]; +} + +/** + * aa_task_setrlimit - test permission to set an rlimit + * @profile - profile confining the task (NOT NULL) + * @resource - the resource being set + * @new_rlim - the new resource limit (NOT NULL) + * + * Control raising the processes hard limit. + * + * Returns: 0 or error code if setting resource failed + */ +int aa_task_setrlimit(struct aa_profile *profile, unsigned int resource, + struct rlimit *new_rlim) +{ + int error = 0; + + if (profile->rlimits.mask & (1 << resource) && + new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max) + + error = audit_resource(profile, resource, new_rlim->rlim_max, + -EACCES); + + return error; +} + +/** + * __aa_transition_rlimits - apply new profile rlimits + * @old: old profile on task (NOT NULL) + * @new: new profile with rlimits to apply (NOT NULL) + */ +void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new) +{ + unsigned int mask = 0; + struct rlimit *rlim, *initrlim; + int i; + + /* for any rlimits the profile controlled reset the soft limit + * to the less of the tasks hard limit and the init tasks soft limit + */ + if (old->rlimits.mask) { + for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) { + if (old->rlimits.mask & mask) { + rlim = current->signal->rlim + i; + initrlim = init_task.signal->rlim + i; + rlim->rlim_cur = min(rlim->rlim_max, + initrlim->rlim_cur); + } + } + } + + /* set any new hard limits as dictated by the new profile */ + if (!new->rlimits.mask) + return; + for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) { + if (!(new->rlimits.mask & mask)) + continue; + + rlim = current->signal->rlim + i; + rlim->rlim_max = min(rlim->rlim_max, + new->rlimits.limits[i].rlim_max); + /* soft limit should not exceed hard limit */ + rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max); + } +} |