From 55669bfa141b488be865341ed12e188967d11308 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 31 Aug 2006 19:26:40 -0400 Subject: [PATCH] [PATCH] audit: AUDIT_PERM support add support for AUDIT_PERM predicate Signed-off-by: Al Viro --- arch/i386/kernel/audit.c | 16 ++++++++++ arch/ia64/ia32/audit.c | 16 ++++++++++ arch/ia64/kernel/audit.c | 19 +++++++++++ arch/powerpc/kernel/audit.c | 21 ++++++++++++ arch/powerpc/kernel/compat_audit.c | 16 ++++++++++ arch/s390/kernel/audit.c | 21 ++++++++++++ arch/s390/kernel/compat_audit.c | 16 ++++++++++ arch/x86_64/ia32/audit.c | 16 ++++++++++ arch/x86_64/kernel/audit.c | 19 +++++++++++ include/linux/audit.h | 7 ++++ kernel/audit.h | 1 + kernel/auditfilter.c | 17 ++++++++++ kernel/auditsc.c | 51 ++++++++++++++++++++++++++++++ 13 files changed, 236 insertions(+) diff --git a/arch/i386/kernel/audit.c b/arch/i386/kernel/audit.c index 28bbc46f75c2..3b97cff41549 100644 --- a/arch/i386/kernel/audit.c +++ b/arch/i386/kernel/audit.c @@ -23,6 +23,22 @@ static unsigned chattr_class[] = { ~0U }; +int audit_classify_syscall(int abi, unsigned syscall) +{ + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 0; + } +} + static int __init audit_classes_init(void) { audit_register_class(AUDIT_CLASS_WRITE, write_class); diff --git a/arch/ia64/ia32/audit.c b/arch/ia64/ia32/audit.c index 798501994bd9..92d7d0c8d93f 100644 --- a/arch/ia64/ia32/audit.c +++ b/arch/ia64/ia32/audit.c @@ -19,3 +19,19 @@ unsigned ia32_read_class[] = { #include ~0U }; + +int ia32_classify_syscall(unsigned syscall) +{ + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 1; + } +} diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c index 99488cdbf5cd..04682555a28c 100644 --- a/arch/ia64/kernel/audit.c +++ b/arch/ia64/kernel/audit.c @@ -23,6 +23,25 @@ static unsigned chattr_class[] = { ~0U }; +int audit_classify_syscall(int abi, unsigned syscall) +{ +#ifdef CONFIG_IA32_SUPPORT + extern int ia32_classify_syscall(unsigned); + if (abi == AUDIT_ARCH_I386) + return ia32_classify_syscall(syscall); +#endif + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_execve: + return 5; + default: + return 0; + } +} + static int __init audit_classes_init(void) { #ifdef CONFIG_IA32_SUPPORT diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c index 24a65e3724e1..7fe5e6300e9a 100644 --- a/arch/powerpc/kernel/audit.c +++ b/arch/powerpc/kernel/audit.c @@ -23,6 +23,27 @@ static unsigned chattr_class[] = { ~0U }; +int audit_classify_syscall(int abi, unsigned syscall) +{ +#ifdef CONFIG_PPC64 + extern int ppc32_classify_syscall(unsigned); + if (abi == AUDIT_ARCH_PPC) + return ppc32_classify_syscall(syscall); +#endif + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 0; + } +} + static int __init audit_classes_init(void) { #ifdef CONFIG_PPC64 diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c index ddc0a64896a2..640d4bb29321 100644 --- a/arch/powerpc/kernel/compat_audit.c +++ b/arch/powerpc/kernel/compat_audit.c @@ -20,3 +20,19 @@ unsigned ppc32_read_class[] = { #include ~0U }; + +int ppc32_classify_syscall(unsigned syscall) +{ + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 1; + } +} diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c index cde57039334c..0741d9193390 100644 --- a/arch/s390/kernel/audit.c +++ b/arch/s390/kernel/audit.c @@ -23,6 +23,27 @@ static unsigned chattr_class[] = { ~0U }; +int audit_classify_syscall(int abi, unsigned syscall) +{ +#ifdef CONFIG_COMPAT + extern int s390_classify_syscall(unsigned); + if (abi == AUDIT_ARCH_S390) + return s390_classify_syscall(syscall); +#endif + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 0; + } +} + static int __init audit_classes_init(void) { #ifdef CONFIG_COMPAT diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c index d9e5f3540d48..16d9436bfa91 100644 --- a/arch/s390/kernel/compat_audit.c +++ b/arch/s390/kernel/compat_audit.c @@ -20,3 +20,19 @@ unsigned s390_read_class[] = { #include ~0U }; + +int s390_classify_syscall(unsigned syscall) +{ + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 1; + } +} diff --git a/arch/x86_64/ia32/audit.c b/arch/x86_64/ia32/audit.c index 798501994bd9..92d7d0c8d93f 100644 --- a/arch/x86_64/ia32/audit.c +++ b/arch/x86_64/ia32/audit.c @@ -19,3 +19,19 @@ unsigned ia32_read_class[] = { #include ~0U }; + +int ia32_classify_syscall(unsigned syscall) +{ + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_socketcall: + return 4; + case __NR_execve: + return 5; + default: + return 1; + } +} diff --git a/arch/x86_64/kernel/audit.c b/arch/x86_64/kernel/audit.c index 36840acb6513..21f33387bef3 100644 --- a/arch/x86_64/kernel/audit.c +++ b/arch/x86_64/kernel/audit.c @@ -23,6 +23,25 @@ static unsigned chattr_class[] = { ~0U }; +int audit_classify_syscall(int abi, unsigned syscall) +{ +#ifdef CONFIG_IA32_EMULATION + extern int ia32_classify_syscall(unsigned); + if (abi == AUDIT_ARCH_I386) + return ia32_classify_syscall(syscall); +#endif + switch(syscall) { + case __NR_open: + return 2; + case __NR_openat: + return 3; + case __NR_execve: + return 5; + default: + return 0; + } +} + static int __init audit_classes_init(void) { #ifdef CONFIG_IA32_EMULATION diff --git a/include/linux/audit.h b/include/linux/audit.h index 1077362a2efb..40a6c26294ae 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -181,6 +181,7 @@ #define AUDIT_EXIT 103 #define AUDIT_SUCCESS 104 /* exit >= 0; value ignored */ #define AUDIT_WATCH 105 +#define AUDIT_PERM 106 #define AUDIT_ARG0 200 #define AUDIT_ARG1 (AUDIT_ARG0+1) @@ -256,6 +257,11 @@ #define AUDIT_ARCH_V850 (EM_V850|__AUDIT_ARCH_LE) #define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE) +#define AUDIT_PERM_EXEC 1 +#define AUDIT_PERM_WRITE 2 +#define AUDIT_PERM_READ 4 +#define AUDIT_PERM_ATTR 8 + struct audit_status { __u32 mask; /* Bit mask for valid entries */ __u32 enabled; /* 1 = enabled, 0 = disabled */ @@ -318,6 +324,7 @@ struct mqstat; #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); +extern int audit_classify_syscall(int abi, unsigned syscall); #ifdef CONFIG_AUDITSYSCALL /* These are defined in auditsc.c */ /* Public API */ diff --git a/kernel/audit.h b/kernel/audit.h index 6aa33b848cf2..a3370232a390 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -104,6 +104,7 @@ static inline int audit_hash_ino(u32 ino) return (ino & (AUDIT_INODE_BUCKETS-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_compare_dname_path(const char *dname, const char *path, int *dirlen); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index e4cafc11c510..a44879b0c72f 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -302,6 +302,15 @@ int __init audit_register_class(int class, unsigned *list) return 0; } +int audit_match_class(int class, unsigned syscall) +{ + if (unlikely(syscall >= AUDIT_BITMASK_SIZE * sizeof(__u32))) + return 0; + if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) + return 0; + return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); +} + /* Common user-space to kernel rule translation. */ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) { @@ -414,6 +423,10 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) case AUDIT_ARG2: case AUDIT_ARG3: break; + case AUDIT_PERM: + if (f->val & ~15) + goto exit_free; + break; case AUDIT_INODE: err = audit_to_inode(&entry->rule, f); if (err) @@ -568,6 +581,10 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, entry->rule.buflen += f->val; entry->rule.filterkey = str; break; + case AUDIT_PERM: + if (f->val & ~15) + goto exit_free; + break; default: goto exit_free; } diff --git a/kernel/auditsc.c b/kernel/auditsc.c index efc1b74bebf3..1bd8827a0102 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -209,6 +209,54 @@ struct audit_context { #endif }; +#define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) +static inline int open_arg(int flags, int mask) +{ + int n = ACC_MODE(flags); + if (flags & (O_TRUNC | O_CREAT)) + n |= AUDIT_PERM_WRITE; + return n & mask; +} + +static int audit_match_perm(struct audit_context *ctx, int mask) +{ + unsigned n = ctx->major; + switch (audit_classify_syscall(ctx->arch, n)) { + case 0: /* native */ + if ((mask & AUDIT_PERM_WRITE) && + audit_match_class(AUDIT_CLASS_WRITE, n)) + return 1; + if ((mask & AUDIT_PERM_READ) && + audit_match_class(AUDIT_CLASS_READ, n)) + return 1; + if ((mask & AUDIT_PERM_ATTR) && + audit_match_class(AUDIT_CLASS_CHATTR, n)) + return 1; + return 0; + case 1: /* 32bit on biarch */ + if ((mask & AUDIT_PERM_WRITE) && + audit_match_class(AUDIT_CLASS_WRITE_32, n)) + return 1; + if ((mask & AUDIT_PERM_READ) && + audit_match_class(AUDIT_CLASS_READ_32, n)) + return 1; + if ((mask & AUDIT_PERM_ATTR) && + audit_match_class(AUDIT_CLASS_CHATTR_32, n)) + return 1; + return 0; + case 2: /* open */ + return mask & ACC_MODE(ctx->argv[1]); + case 3: /* openat */ + return mask & ACC_MODE(ctx->argv[2]); + case 4: /* socketcall */ + return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); + case 5: /* execve */ + return mask & AUDIT_PERM_EXEC; + default: + return 0; + } +} + /* Determine if any context name data matches a rule's watch data */ /* Compare a task_struct with an audit_rule. Return 1 on match, 0 * otherwise. */ @@ -397,6 +445,9 @@ static int audit_filter_rules(struct task_struct *tsk, /* ignore this field for filtering */ result = 1; break; + case AUDIT_PERM: + result = audit_match_perm(ctx, f->val); + break; } if (!result)