From: Al Viro Date: Sat, 1 Jul 2006 07:56:16 +0000 (-0400) Subject: [PATCH] audit syscall classes X-Git-Tag: v2.6.18-rc1~191^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b915543b46a2aa599fdd2169e51bcfd88812a12b;p=linux-2.6 [PATCH] audit syscall classes Allow to tie upper bits of syscall bitmap in audit rules to kernel-defined sets of syscalls. Infrastructure, a couple of classes (with 32bit counterparts for biarch targets) and actual tie-in on i386, amd64 and ia64. Signed-off-by: Al Viro --- diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile index 5e70c2fb27..cbc1184e94 100644 --- a/arch/i386/kernel/Makefile +++ b/arch/i386/kernel/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_VM86) += vm86.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o obj-$(CONFIG_HPET_TIMER) += hpet.o obj-$(CONFIG_K8_NB) += k8.o +obj-$(CONFIG_AUDIT) += audit.o EXTRA_AFLAGS := -traditional diff --git a/arch/i386/kernel/audit.c b/arch/i386/kernel/audit.c new file mode 100644 index 0000000000..5a53c6f371 --- /dev/null +++ b/arch/i386/kernel/audit.c @@ -0,0 +1,23 @@ +#include +#include +#include +#include + +static unsigned dir_class[] = { +#include +~0U +}; + +static unsigned chattr_class[] = { +#include +~0U +}; + +static int __init audit_classes_init(void) +{ + audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class); + audit_register_class(AUDIT_CLASS_CHATTR, chattr_class); + return 0; +} + +__initcall(audit_classes_init); diff --git a/arch/ia64/ia32/Makefile b/arch/ia64/ia32/Makefile index 61cb60affd..baad8c7699 100644 --- a/arch/ia64/ia32/Makefile +++ b/arch/ia64/ia32/Makefile @@ -4,6 +4,7 @@ obj-y := ia32_entry.o sys_ia32.o ia32_signal.o \ ia32_support.o ia32_traps.o binfmt_elf32.o ia32_ldt.o +obj-$(CONFIG_AUDIT) += audit.o # Don't let GCC uses f16-f31 so that save_ia32_fpstate_live() and # restore_ia32_fpstate_live() can be sure the live register contain user-level state. diff --git a/arch/ia64/ia32/audit.c b/arch/ia64/ia32/audit.c new file mode 100644 index 0000000000..ab94f2e58c --- /dev/null +++ b/arch/ia64/ia32/audit.c @@ -0,0 +1,11 @@ +#include + +unsigned ia32_dir_class[] = { +#include +~0U +}; + +unsigned ia32_chattr_class[] = { +#include +~0U +}; diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile index 09a0dbc17f..0e4553f320 100644 --- a/arch/ia64/kernel/Makefile +++ b/arch/ia64/kernel/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_CPU_FREQ) += cpufreq/ obj-$(CONFIG_IA64_MCA_RECOVERY) += mca_recovery.o obj-$(CONFIG_KPROBES) += kprobes.o jprobes.o obj-$(CONFIG_IA64_UNCACHED_ALLOCATOR) += uncached.o +obj-$(CONFIG_AUDIT) += audit.o mca_recovery-y += mca_drv.o mca_drv_asm.o # The gate DSO image is built using a special linker script. diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c new file mode 100644 index 0000000000..f2512931cc --- /dev/null +++ b/arch/ia64/kernel/audit.c @@ -0,0 +1,29 @@ +#include +#include +#include +#include + +static unsigned dir_class[] = { +#include +~0U +}; + +static unsigned chattr_class[] = { +#include +~0U +}; + +static int __init audit_classes_init(void) +{ +#ifdef CONFIG_IA32_SUPPORT + extern __u32 ia32_dir_class[]; + extern __u32 ia32_chattr_class[]; + audit_register_class(AUDIT_CLASS_DIR_WRITE_32, ia32_dir_class); + audit_register_class(AUDIT_CLASS_CHATTR_32, ia32_chattr_class); +#endif + audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class); + audit_register_class(AUDIT_CLASS_CHATTR, chattr_class); + return 0; +} + +__initcall(audit_classes_init); diff --git a/arch/x86_64/ia32/Makefile b/arch/x86_64/ia32/Makefile index e9263b4975..62bc5f56da 100644 --- a/arch/x86_64/ia32/Makefile +++ b/arch/x86_64/ia32/Makefile @@ -11,6 +11,9 @@ obj-$(CONFIG_IA32_EMULATION) += $(sysv-y) obj-$(CONFIG_IA32_AOUT) += ia32_aout.o +audit-class-$(CONFIG_AUDIT) := audit.o +obj-$(CONFIG_IA32_EMULATION) += $(audit-class-y) + $(obj)/syscall32_syscall.o: \ $(foreach F,sysenter syscall,$(obj)/vsyscall-$F.so) diff --git a/arch/x86_64/ia32/audit.c b/arch/x86_64/ia32/audit.c new file mode 100644 index 0000000000..ab94f2e58c --- /dev/null +++ b/arch/x86_64/ia32/audit.c @@ -0,0 +1,11 @@ +#include + +unsigned ia32_dir_class[] = { +#include +~0U +}; + +unsigned ia32_chattr_class[] = { +#include +~0U +}; diff --git a/arch/x86_64/kernel/Makefile b/arch/x86_64/kernel/Makefile index aeb9c560be..819e84ec5b 100644 --- a/arch/x86_64/kernel/Makefile +++ b/arch/x86_64/kernel/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_KPROBES) += kprobes.o obj-$(CONFIG_X86_PM_TIMER) += pmtimer.o obj-$(CONFIG_X86_VSMP) += vsmp.o obj-$(CONFIG_K8_NB) += k8.o +obj-$(CONFIG_AUDIT) += audit.o obj-$(CONFIG_MODULES) += module.o diff --git a/arch/x86_64/kernel/audit.c b/arch/x86_64/kernel/audit.c new file mode 100644 index 0000000000..a067aa468a --- /dev/null +++ b/arch/x86_64/kernel/audit.c @@ -0,0 +1,29 @@ +#include +#include +#include +#include + +static unsigned dir_class[] = { +#include +~0U +}; + +static unsigned chattr_class[] = { +#include +~0U +}; + +static int __init audit_classes_init(void) +{ +#ifdef CONFIG_IA32_EMULATION + extern __u32 ia32_dir_class[]; + extern __u32 ia32_chattr_class[]; + audit_register_class(AUDIT_CLASS_DIR_WRITE_32, ia32_dir_class); + audit_register_class(AUDIT_CLASS_CHATTR_32, ia32_chattr_class); +#endif + audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class); + audit_register_class(AUDIT_CLASS_CHATTR, chattr_class); + return 0; +} + +__initcall(audit_classes_init); diff --git a/include/asm-generic/audit_change_attr.h b/include/asm-generic/audit_change_attr.h new file mode 100644 index 0000000000..cb05bf6974 --- /dev/null +++ b/include/asm-generic/audit_change_attr.h @@ -0,0 +1,18 @@ +__NR_chmod, +__NR_fchmod, +__NR_chown, +__NR_fchown, +__NR_lchown, +__NR_setxattr, +__NR_lsetxattr, +__NR_fsetxattr, +__NR_removexattr, +__NR_lremovexattr, +__NR_fremovexattr, +__NR_fchownat, +__NR_fchmodat, +#ifdef __NR_chown32 +__NR_chown32, +__NR_fchown32, +__NR_lchown32, +#endif diff --git a/include/asm-generic/audit_dir_write.h b/include/asm-generic/audit_dir_write.h new file mode 100644 index 0000000000..161a7a58fb --- /dev/null +++ b/include/asm-generic/audit_dir_write.h @@ -0,0 +1,14 @@ +__NR_rename, +__NR_mkdir, +__NR_rmdir, +__NR_creat, +__NR_link, +__NR_unlink, +__NR_symlink, +__NR_mknod, +__NR_mkdirat, +__NR_mknodat, +__NR_unlinkat, +__NR_renameat, +__NR_linkat, +__NR_symlinkat, diff --git a/include/linux/audit.h b/include/linux/audit.h index c211f0a2ab..b27d7debc5 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -127,6 +127,12 @@ #define AUDIT_WORD(nr) ((__u32)((nr)/32)) #define AUDIT_BIT(nr) (1 << ((nr) - AUDIT_WORD(nr)*32)) +#define AUDIT_SYSCALL_CLASSES 16 +#define AUDIT_CLASS_DIR_WRITE 0 +#define AUDIT_CLASS_DIR_WRITE_32 1 +#define AUDIT_CLASS_CHATTR 2 +#define AUDIT_CLASS_CHATTR_32 3 + /* This bitmask is used to validate user input. It represents all bits that * are currently used in an audit field constant understood by the kernel. * If you are adding a new #define AUDIT_, please ensure that @@ -307,6 +313,7 @@ struct mqstat; #define AUDITSC_SUCCESS 1 #define AUDITSC_FAILURE 2 #define AUDITSC_RESULT(x) ( ((long)(x))<0?AUDITSC_FAILURE:AUDITSC_SUCCESS ) +extern int __init audit_register_class(int class, unsigned *list); #ifdef CONFIG_AUDITSYSCALL /* These are defined in auditsc.c */ /* Public API */ diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 7f2ea8b84a..5b4e16276c 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -279,6 +279,29 @@ static int audit_to_watch(struct audit_krule *krule, char *path, int len, return 0; } +static __u32 *classes[AUDIT_SYSCALL_CLASSES]; + +int __init audit_register_class(int class, unsigned *list) +{ + __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); + if (!p) + return -ENOMEM; + while (*list != ~0U) { + unsigned n = *list++; + if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { + kfree(p); + return -EINVAL; + } + p[AUDIT_WORD(n)] |= AUDIT_BIT(n); + } + if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { + kfree(p); + return -EINVAL; + } + classes[class] = p; + return 0; +} + /* Common user-space to kernel rule translation. */ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) { @@ -322,6 +345,22 @@ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) for (i = 0; i < AUDIT_BITMASK_SIZE; i++) entry->rule.mask[i] = rule->mask[i]; + for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { + int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; + __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; + __u32 *class; + + if (!(*p & AUDIT_BIT(bit))) + continue; + *p &= ~AUDIT_BIT(bit); + class = classes[i]; + if (class) { + int j; + for (j = 0; j < AUDIT_BITMASK_SIZE; j++) + entry->rule.mask[j] |= class[j]; + } + } + return entry; exit_err: