diff options
Diffstat (limited to 'security/apparmor/capability.c')
| -rw-r--r-- | security/apparmor/capability.c | 111 |
1 files changed, 86 insertions, 25 deletions
diff --git a/security/apparmor/capability.c b/security/apparmor/capability.c index 326a51838ef2..b9ea6bc45c1a 100644 --- a/security/apparmor/capability.c +++ b/security/apparmor/capability.c @@ -12,6 +12,7 @@ #include <linux/errno.h> #include <linux/gfp.h> #include <linux/security.h> +#include <linux/timekeeping.h> #include "include/apparmor.h" #include "include/capability.h" @@ -26,20 +27,22 @@ struct aa_sfs_entry aa_sfs_entry_caps[] = { AA_SFS_FILE_STRING("mask", AA_SFS_CAPS_MASK), + AA_SFS_FILE_BOOLEAN("extended", 1), { } }; struct audit_cache { - struct aa_profile *profile; - kernel_cap_t caps; + const struct cred *ad_subj_cred; + /* Capabilities go from 0 to CAP_LAST_CAP */ + u64 ktime_ns_expiration[CAP_LAST_CAP+1]; }; 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) + * @ab: audit buffer (NOT NULL) + * @va: audit struct to audit data from (NOT NULL) */ static void audit_cb(struct audit_buffer *ab, void *va) { @@ -51,7 +54,7 @@ static void audit_cb(struct audit_buffer *ab, void *va) /** * audit_caps - audit a capability - * @sa: audit data + * @ad: audit data * @profile: profile being tested for confinement (NOT NULL) * @cap: capability tested * @error: error code returned by test @@ -59,17 +62,18 @@ static void audit_cb(struct audit_buffer *ab, void *va) * 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 + * Returns: 0 or ad->error on success, error code on failure */ -static int audit_caps(struct common_audit_data *sa, struct aa_profile *profile, +static int audit_caps(struct apparmor_audit_data *ad, struct aa_profile *profile, int cap, int error) { - struct aa_ruleset *rules = list_first_entry(&profile->rules, - typeof(*rules), list); + const u64 AUDIT_CACHE_TIMEOUT_NS = 1000*1000*1000; /* 1 second */ + + struct aa_ruleset *rules = profile->label.rules[0]; struct audit_cache *ent; int type = AUDIT_APPARMOR_AUTO; - aad(sa)->error = error; + ad->error = error; if (likely(!error)) { /* test if auditing is being forced */ @@ -89,19 +93,20 @@ static int audit_caps(struct common_audit_data *sa, struct aa_profile *profile, /* Do simple duplicate message elimination */ ent = &get_cpu_var(audit_cache); - if (profile == ent->profile && cap_raised(ent->caps, cap)) { + /* If the capability was never raised the timestamp check would also catch that */ + if (ad->subj_cred == ent->ad_subj_cred && ktime_get_ns() <= ent->ktime_ns_expiration[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_cred(ent->ad_subj_cred); + ent->ad_subj_cred = get_cred(ad->subj_cred); + ent->ktime_ns_expiration[cap] = ktime_get_ns() + AUDIT_CACHE_TIMEOUT_NS; } put_cpu_var(audit_cache); - return aa_audit(type, profile, sa, audit_cb); + return aa_audit(type, profile, ad, audit_cb); } /** @@ -109,17 +114,39 @@ static int audit_caps(struct common_audit_data *sa, struct aa_profile *profile, * @profile: profile being enforced (NOT NULL, NOT unconfined) * @cap: capability to test if allowed * @opts: CAP_OPT_NOAUDIT bit determines whether audit record is generated - * @sa: audit data (MAY BE NULL indicating no auditing) + * @ad: audit data (NOT NULL) * * Returns: 0 if allowed else -EPERM */ static int profile_capable(struct aa_profile *profile, int cap, - unsigned int opts, struct common_audit_data *sa) + unsigned int opts, struct apparmor_audit_data *ad) { - struct aa_ruleset *rules = list_first_entry(&profile->rules, - typeof(*rules), list); + struct aa_ruleset *rules = profile->label.rules[0]; + aa_state_t state; int error; + state = RULE_MEDIATES(rules, ad->class); + if (state) { + struct aa_perms perms = { }; + u32 request; + + /* caps broken into 256 x 32 bit permission chunks */ + state = aa_dfa_next(rules->policy->dfa, state, cap >> 5); + request = 1 << (cap & 0x1f); + perms = *aa_lookup_perms(rules->policy, state); + aa_apply_modes_to_perms(profile, &perms); + + if (opts & CAP_OPT_NOAUDIT) { + if (perms.complain & request) + ad->info = "optional: no audit"; + else + ad = NULL; + } + return aa_check_perms(profile, &perms, request, ad, + audit_cb); + } + + /* fallback to old caps mediation that doesn't support conditionals */ if (cap_raised(rules->caps.allow, cap) && !cap_raised(rules->caps.denied, cap)) error = 0; @@ -132,14 +159,15 @@ static int profile_capable(struct aa_profile *profile, int cap, /* audit the cap request in complain mode but note that it * should be optional. */ - aad(sa)->info = "optional: no audit"; + ad->info = "optional: no audit"; } - return audit_caps(sa, profile, cap, error); + return audit_caps(ad, profile, cap, error); } /** * aa_capable - test permission to use capability + * @subj_cred: cred we are testing capability against * @label: label being tested for capability (NOT NULL) * @cap: capability to be tested * @opts: CAP_OPT_NOAUDIT bit determines whether audit record is generated @@ -148,15 +176,48 @@ static int profile_capable(struct aa_profile *profile, int cap, * * Returns: 0 on success, or else an error code. */ -int aa_capable(struct aa_label *label, int cap, unsigned int opts) +int aa_capable(const struct cred *subj_cred, struct aa_label *label, + int cap, unsigned int opts) { struct aa_profile *profile; int error = 0; - DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_CAP, AA_CLASS_CAP, OP_CAPABLE); + DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_CAP, AA_CLASS_CAP, OP_CAPABLE); - sa.u.cap = cap; + ad.subj_cred = subj_cred; + ad.common.u.cap = cap; error = fn_for_each_confined(label, profile, - profile_capable(profile, cap, opts, &sa)); + profile_capable(profile, cap, opts, &ad)); return error; } + +kernel_cap_t aa_profile_capget(struct aa_profile *profile) +{ + struct aa_ruleset *rules = profile->label.rules[0]; + aa_state_t state; + + state = RULE_MEDIATES(rules, AA_CLASS_CAP); + if (state) { + kernel_cap_t caps = CAP_EMPTY_SET; + int i; + + /* caps broken into up to 256, 32 bit permission chunks */ + for (i = 0; i < (CAP_LAST_CAP >> 5); i++) { + struct aa_perms perms = { }; + aa_state_t tmp; + + tmp = aa_dfa_next(rules->policy->dfa, state, i); + perms = *aa_lookup_perms(rules->policy, tmp); + aa_apply_modes_to_perms(profile, &perms); + caps.val |= ((u64)(perms.allow)) << (i * 5); + caps.val |= ((u64)(perms.complain)) << (i * 5); + } + return caps; + } + + /* fallback to old caps */ + if (COMPLAIN_MODE(profile)) + return CAP_FULL_SET; + + return rules->caps.allow; +} |