diff options
Diffstat (limited to 'security/apparmor/capability.c')
| -rw-r--r-- | security/apparmor/capability.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/security/apparmor/capability.c b/security/apparmor/capability.c new file mode 100644 index 000000000..1101c6f64 --- /dev/null +++ b/security/apparmor/capability.c @@ -0,0 +1,143 @@ +/* + * 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 aa_fs_entry aa_fs_entry_caps[] = { + AA_FS_FILE_STRING("mask", AA_FS_CAPS_MASK), + { } +}; + +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 being tested for confinement (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, int cap, int error) +{ + struct audit_cache *ent; + int type = AUDIT_APPARMOR_AUTO; + struct common_audit_data sa; + struct apparmor_audit_data aad = {0,}; + sa.type = LSM_AUDIT_DATA_CAP; + sa.aad = &aad; + 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 + * @profile: profile being tested against (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 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, cap, error); +} |