Implement audit container identifier filtering using the AUDIT_CONTID field name to send an 8-character string representing a u64 since the value field is only u32. Sending it as two u32 was considered, but gathering and comparing two fields was more complex. The feature indicator is AUDIT_FEATURE_BITMAP_CONTAINERID. Please see the github audit kernel issue for the contid filter feature: https://github.com/linux-audit/audit-kernel/issues/91 Please see the github audit userspace issue for filter additions: https://github.com/linux-audit/audit-userspace/issues/40 Please see the github audit testsuiite issue for the test case: https://github.com/linux-audit/audit-testsuite/issues/64 Please see the github audit wiki for the feature overview: https://github.com/linux-audit/audit-kernel/wiki/RFE-Audit-Container-ID Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx> Acked-by: Serge Hallyn <serge@xxxxxxxxxx> Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx> Reviewed-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx> --- include/linux/audit.h | 1 + include/uapi/linux/audit.h | 5 ++++- kernel/audit.c | 5 +++++ kernel/audit.h | 3 +++ kernel/auditfilter.c | 46 ++++++++++++++++++++++++++++++++++++++ kernel/auditsc.c | 3 +++ 6 files changed, 62 insertions(+), 1 deletion(-) diff --git a/include/linux/audit.h b/include/linux/audit.h index 9f0238f7960f..056a7c9a12a2 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -69,6 +69,7 @@ struct audit_field { u32 type; union { u32 val; + u64 val64; kuid_t uid; kgid_t gid; struct { diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h index 94dcf3085658..66350e572e41 100644 --- a/include/uapi/linux/audit.h +++ b/include/uapi/linux/audit.h @@ -271,6 +271,7 @@ #define AUDIT_LOGINUID_SET 24 #define AUDIT_SESSIONID 25 /* Session ID */ #define AUDIT_FSTYPE 26 /* FileSystem Type */ +#define AUDIT_CONTID 27 /* Container ID */ /* These are ONLY useful when checking * at syscall exit time (AUDIT_AT_EXIT). */ @@ -353,6 +354,7 @@ enum { #define AUDIT_FEATURE_BITMAP_SESSIONID_FILTER 0x00000010 #define AUDIT_FEATURE_BITMAP_LOST_RESET 0x00000020 #define AUDIT_FEATURE_BITMAP_FILTER_FS 0x00000040 +#define AUDIT_FEATURE_BITMAP_CONTAINERID 0x00000080 #define AUDIT_FEATURE_BITMAP_ALL (AUDIT_FEATURE_BITMAP_BACKLOG_LIMIT | \ AUDIT_FEATURE_BITMAP_BACKLOG_WAIT_TIME | \ @@ -360,7 +362,8 @@ enum { AUDIT_FEATURE_BITMAP_EXCLUDE_EXTEND | \ AUDIT_FEATURE_BITMAP_SESSIONID_FILTER | \ AUDIT_FEATURE_BITMAP_LOST_RESET | \ - AUDIT_FEATURE_BITMAP_FILTER_FS) + AUDIT_FEATURE_BITMAP_FILTER_FS | \ + AUDIT_FEATURE_BITMAP_CONTAINERID) /* deprecated: AUDIT_VERSION_* */ #define AUDIT_VERSION_LATEST AUDIT_FEATURE_BITMAP_ALL diff --git a/kernel/audit.c b/kernel/audit.c index b23f004f4000..300daf2bcb16 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2488,6 +2488,11 @@ int audit_log_container_id_ctx(struct audit_context *context) return record; } +int audit_contid_comparator(struct task_struct *tsk, u32 op, u64 right) +{ + return audit_comparator64(audit_get_contid(tsk), op, right); +} + void audit_log_key(struct audit_buffer *ab, char *key) { audit_log_format(ab, " key="); diff --git a/kernel/audit.h b/kernel/audit.h index 40e609787a0c..48c429c2d544 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -218,12 +218,15 @@ extern void *audit_contobj_get_bytask(struct task_struct *tsk); extern void audit_contobj_put(void **cont, int count); extern int audit_log_container_id(struct audit_context *context, void *cont); extern int audit_log_container_id_ctx(struct audit_context *context); +extern int audit_contid_comparator(struct task_struct *tsk, const u32 op, + const u64 right); /* Indicates that audit should log the full pathname. */ #define AUDIT_NAME_FULL -1 extern int audit_match_class(int class, unsigned syscall); extern int audit_comparator(const u32 left, const u32 op, const u32 right); +extern int audit_comparator64(const u64 left, const u32 op, const u64 right); extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right); extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right); extern int parent_len(const char *path); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 333b3bcfc545..9362ee9cc414 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -399,6 +399,7 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f) case AUDIT_FILETYPE: case AUDIT_FIELD_COMPARE: case AUDIT_EXE: + case AUDIT_CONTID: /* only equal and not equal valid ops */ if (f->op != Audit_not_equal && f->op != Audit_equal) return -EINVAL; @@ -590,6 +591,14 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, entry->rule.buflen += f_val; entry->rule.exe = audit_mark; break; + case AUDIT_CONTID: + if (f_val != sizeof(u64)) + goto exit_free; + str = audit_unpack_string(&bufp, &remain, f_val); + if (IS_ERR(str)) + goto exit_free; + f->val64 = ((u64 *)str)[0]; + break; default: f->val = f_val; break; @@ -675,6 +684,11 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) data->buflen += data->values[i] = audit_pack_string(&bufp, audit_mark_path(krule->exe)); break; + case AUDIT_CONTID: + data->buflen += data->values[i] = sizeof(u64); + memcpy(bufp, &f->val64, sizeof(u64)); + bufp += sizeof(u64); + break; case AUDIT_LOGINUID_SET: if (krule->pflags & AUDIT_LOGINUID_LEGACY && !f->val) { data->fields[i] = AUDIT_LOGINUID; @@ -761,6 +775,10 @@ static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) if (!gid_eq(a->fields[i].gid, b->fields[i].gid)) return 1; break; + case AUDIT_CONTID: + if (a->fields[i].val64 != b->fields[i].val64) + return 1; + break; default: if (a->fields[i].val != b->fields[i].val) return 1; @@ -1216,6 +1234,30 @@ int audit_comparator(u32 left, u32 op, u32 right) } } +int audit_comparator64(u64 left, u32 op, u64 right) +{ + switch (op) { + case Audit_equal: + return (left == right); + case Audit_not_equal: + return (left != right); + case Audit_lt: + return (left < right); + case Audit_le: + return (left <= right); + case Audit_gt: + return (left > right); + case Audit_ge: + return (left >= right); + case Audit_bitmask: + return (left & right); + case Audit_bittest: + return ((left & right) == right); + default: + return 0; + } +} + int audit_uid_comparator(kuid_t left, u32 op, kuid_t right) { switch (op) { @@ -1350,6 +1392,10 @@ int audit_filter(int msgtype, unsigned int listtype) result = audit_comparator(audit_loginuid_set(current), f->op, f->val); break; + case AUDIT_CONTID: + result = audit_contid_comparator(current, f->op, + f->val64); + break; case AUDIT_MSGTYPE: result = audit_comparator(msgtype, f->op, f->val); break; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index df26d0aa5e6d..7ef5502e8ef3 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -656,6 +656,9 @@ static int audit_filter_rules(struct task_struct *tsk, result = audit_comparator(ctx->sockaddr->ss_family, f->op, f->val); break; + case AUDIT_CONTID: + result = audit_contid_comparator(tsk, f->op, f->val64); + break; case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: -- 2.18.4
