我正在开发一个项目,我必须在OSX(10.10.5)上挂钩80％-90％的系统调用函数.我是从内核扩展中做到这一点的.由于我必须(un)挂钩许多函数,我想将原始内核函数存储到函数指针数组中,我可以快速查找数组,以便在取消时恢复原始函数.
int (*kern_open)(struct proc *,struct open_args *,int *);
int mon_open(struct proc *p,struct open_args *uap,int *retval) {
kern_open = sysent[SYS_open].sy_call;
sysent[SYS_open].sy_call = mon_open;
这样可行,kern_open函数用于存储调用系统调用的原始内核函数. mon_open是我的挂钩功能.
我想要实现的目标如下：因此,在取消挂钩时,我可以通过KernSysCall数组进行迭代并恢复功能.
// global array of function pointers that all have the same func def.
static int (*KernSysCall[SYS_MAXSYSCALL])(struct proc *,struct args *,int *);
KernSysCall[SYS_open] = sysent[SYS_open].sy_call;
sysent[SYS_open].sy_call = mon_open;
恢复：sysent [SYS_open] .sy_call = KernSysCall [SYS_open];
但是,将原始内核函数存储在函数指针数组中会导致内核崩溃.由于错误,我还无法附加lldb：KDP_REATTACH失败错误.我希望有人知道导致内核恐慌的原因.
下面是内核恐慌的日志.
Anonymous UUID: 052D64D2-A43C-99F8-D221-B591991E54AF Wed Nov 11 12:55:06 2015 *** Panic Report *** panic(cpu 0 caller 0xffffff80093f0024): Kernel trap at 0x0000000000000000,type 14=page fault,registers: CR0: 0x0000000080010033,CR2: 0x0000000000000000,CR3: 0x00000000769bb018,CR4: 0x00000000001606e0 RAX: 0x0000000000000000,RBX: 0xffffff80115e3fc0,RCX: 0x0000000000000001,RDX: 0xffffff80115e3fc0 RSP: 0xffffff8068dabaf8,RBP: 0xffffff8068dabf50,RSI: 0xffffff80115e3f80,RDI: 0xffffff8010059cf0 R8: 0xffffff7f8afaccdf,R9: 0xffffff8009ae2a18,R10: 0xffffff8009939740,R11: 0x0000000000000000 R12: 0xffffff8010059cf0,R13: 0x0000000000000005,R14: 0xffffff80115e3f80,R15: 0xffffff801188b480 RFL: 0x0000000000010282,RIP: 0x0000000000000000,CS: 0x0000000000000008,SS: 0x0000000000000010 Fault CR2: 0x0000000000000000,Error code: 0x0000000000000010,Fault cpu: 0x0 VMM Backtrace (cpu 0),Frame : Return Address 0xffffff8068dab790 : 0xffffff80092e4ed1 mach_kernel : _panic + 0xd1 0xffffff8068dab810 : 0xffffff80093f0024 mach_kernel : _kernel_trap + 0x664 0xffffff8068dab9e0 : 0xffffff800940de53 mach_kernel : trap_from_kernel + 0x26 0xffffff8068daba00 : 0x0 0xffffff8068dabf50 : 0xffffff800982c0c1 mach_kernel : _unix_syscall64 + 0x2f1 0xffffff8068dabfb0 : 0xffffff800940e656 mach_kernel : _hndl_unix_scall64 + 0x16 BSD process name corresponding to current thread: xpcproxy Boot args: debug=0x14e kext-dev-mode=1 -v keepsyms=1 kmem=1 Mac OS version: 14F27 Kernel version: Darwin Kernel Version 14.5.0: Wed Jul 29 02:26:53 PDT 2015; root:xnu-2782.40.9~1/DEVELOPMENT_X86_64 Kernel UUID: C75BDFDD-9F27-3694-BB80-73CF991C13D8 Kernel slide: 0x0000000009000000 Kernel text base: 0xffffff8009200000 __HIB text base: 0xffffff8009100000 System model name: VMware7,1 (Mac-66F35F19FE2A0D05) System uptime in nanoseconds: 251264993940 last loaded kext at 249789197520: my.kext 1 (addr 0xffffff7f8afa9000,size 57344) last unloaded kext at 116769666233: com.apple.driver.AppleFileSystemDriver 3.0.1 (addr 0xffffff7f8aed3000,size 16384) loaded kexts: my.kext 1 [more kexts here]
在请求中,mon_open()的代码：
int
mon_open(struct proc *p,int *r) {
int error;
char processname[MAXCOMLEN+1];
char intercepted_path[MAXPATHLEN];
pid_t pid = proc_pid(p);
proc_name(pid,processname,sizeof(processname));
size_t dummy = 0;
error = copyinstr((void *)uap->path,(void *)intercepted_path,MAXPATHLEN,&dummy);
if (!error) {
printf("[MYKEXT] open called with path: %s,PID: %d,processname: %s\n",intercepted_path,pid,processname);
}
return kern_open(p,uap,r);
}
非常感谢你提前！
