From 74f2345b6be1410f824cb7dd638d2c10a9709379 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Mon, 4 Jun 2007 17:00:14 -0400 Subject: [PATCH] [PATCH] allow audit filtering on bit & operations Right now the audit filter can match on = != > < >= blah blah blah. This allow the filter to also look at bitwise AND operations, & Signed-off-by: Eric Paris Signed-off-by: Al Viro --- include/linux/audit.h | 30 +++++++++++++++++------------- kernel/auditfilter.c | 11 +++++++++++ 2 files changed, 28 insertions(+), 13 deletions(-) diff --git a/include/linux/audit.h b/include/linux/audit.h index 8ca7ca0b47..a35859ab2f 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -161,7 +161,7 @@ * are currently used in an audit field constant understood by the kernel. * If you are adding a new #define AUDIT_, please ensure that * AUDIT_UNUSED_BITS is updated if need be. */ -#define AUDIT_UNUSED_BITS 0x0FFFFC00 +#define AUDIT_UNUSED_BITS 0x07FFFC00 /* Rule fields */ @@ -213,25 +213,29 @@ #define AUDIT_NEGATE 0x80000000 /* These are the supported operators. - * 4 2 1 - * = > < - * ------- - * 0 0 0 0 nonsense - * 0 0 1 1 < - * 0 1 0 2 > - * 0 1 1 3 != - * 1 0 0 4 = - * 1 0 1 5 <= - * 1 1 0 6 >= - * 1 1 1 7 all operators + * 4 2 1 8 + * = > < ? + * ---------- + * 0 0 0 0 00 nonsense + * 0 0 0 1 08 & bit mask + * 0 0 1 0 10 < + * 0 1 0 0 20 > + * 0 1 1 0 30 != + * 1 0 0 0 40 = + * 1 0 0 1 48 &= bit test + * 1 0 1 0 50 <= + * 1 1 0 0 60 >= + * 1 1 1 1 78 all operators */ +#define AUDIT_BIT_MASK 0x08000000 #define AUDIT_LESS_THAN 0x10000000 #define AUDIT_GREATER_THAN 0x20000000 #define AUDIT_NOT_EQUAL 0x30000000 #define AUDIT_EQUAL 0x40000000 +#define AUDIT_BIT_TEST (AUDIT_BIT_MASK|AUDIT_EQUAL) #define AUDIT_LESS_THAN_OR_EQUAL (AUDIT_LESS_THAN|AUDIT_EQUAL) #define AUDIT_GREATER_THAN_OR_EQUAL (AUDIT_GREATER_THAN|AUDIT_EQUAL) -#define AUDIT_OPERATORS (AUDIT_EQUAL|AUDIT_NOT_EQUAL) +#define AUDIT_OPERATORS (AUDIT_EQUAL|AUDIT_NOT_EQUAL|AUDIT_BIT_MASK) /* Status symbols */ /* Mask values */ diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 0ea96bab91..359645cff5 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -456,6 +456,13 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) case AUDIT_DEVMINOR: case AUDIT_EXIT: case AUDIT_SUCCESS: + /* bit ops are only useful on syscall args */ + if (f->op == AUDIT_BIT_MASK || + f->op == AUDIT_BIT_TEST) { + err = -EINVAL; + goto exit_free; + } + break; case AUDIT_ARG0: case AUDIT_ARG1: case AUDIT_ARG2: @@ -1566,6 +1573,10 @@ int audit_comparator(const u32 left, const u32 op, const u32 right) return (left > right); case AUDIT_GREATER_THAN_OR_EQUAL: return (left >= right); + case AUDIT_BIT_MASK: + return (left & right); + case AUDIT_BIT_TEST: + return ((left & right) == right); } BUG(); return 0; -- 2.39.5