我想将一组数据发送到内核空间,(我在我的 kext 中使用了回调函数)问题是当我使用发送函数时,我看到了一些奇怪的东西,我在 2 个场景中解释了:1)... char f[] ={'1','2','3','4','5','6'}; 发送(袜子,f,sizeof(f),0);好吧,当我 printf 我在 kext 中收到的内容时:123456
2) ... // 我用 0 替换 f[2]
字符 f[]={'1','2', 0 ,'4','5','6'}; 发送(袜子,f,sizeof(f),0);
但是这一次,当我 printf 我在 kext 中收到的内容时:120000
似乎发送函数在第一个 0 字节之后的每个字节都为零?到底是怎么回事?这是发送功能错误吗?我使用了 xcode 4.1,我的操作系统是 lion 这里是用户空间部分:
int main(int argc, char* const*argv)
{
struct ctl_info ctl_info;
struct sockaddr_ctl sc;
char str[MAX_STRING_LEN];
int sock = socket(PF_SYSTEM, SOCK_DGRAM, SYSPROTO_CONTROL);
if (sock < 0)
return -1;
bzero(&ctl_info, sizeof(struct ctl_info));
strcpy(ctl_info.ctl_name, "pana.ifmonitor.nke.foo");
if (ioctl(sock, CTLIOCGINFO, &ctl_info) == -1)
return -1;
bzero(&sc, sizeof(struct sockaddr_ctl));
sc.sc_len = sizeof(struct sockaddr_ctl);
sc.sc_family = AF_SYSTEM;
sc.ss_sysaddr = SYSPROTO_CONTROL;
sc.sc_id = ctl_info.ctl_id;
sc.sc_unit = 0;
if (connect(sock, (struct sockaddr *)&sc, sizeof(struct sockaddr_ctl)))
return -1;
unsigned char data_send[]={'a','l','i','0','1','2','4','l','i',0,'1','2','4','l','i','0','1'};
size_t data_recive;
int j=0;
char data_rcv[8192];
send( sock, data_send, 17*sizeof(char), 10 );
printf("\n");
sleep(1);
close(sock);
return 0;
}
这是负责获取用户空间数据的内核空间代码的一部分:
errno_t EPHandleWrite(kern_ctl_ref ctlref, unsigned int unit, void *userdata,mbuf_t m, int flags)
{
printf("\n EPHandleWrite called---------------------- \n");
//char data_rec[50];
//unsigned char *ptr = (unsigned char*)mbuf_data(m);
//char ch;
//mbuf_copydata(m, 0, 50, data_rec);
//strncpy(&ch, ptr, 1 );
size_t data_lenght;
data_lenght = mbuf_pkthdr_len(m);
char data_receive[data_lenght];
strncpy( data_receive, ( char * ) mbuf_data(m) , data_lenght );
printf("data recied %lu\n",data_lenght);
for(int i=0;i<data_lenght;++i)
{
printf("%X ",data_receive[i]);
}
return 0
}
好吧,它在控制台中打印:61 6C 69 30 31 32 34 6C 69 0 0 0 0 0 0 0 0 当我将发送数据更改为:
{'a','l','i','0','1','2','4','l','i',**'0'**,'1','2','4','l','i','0','1'};
我得到正确的,实际上我在发送数据中的第一个零字节之后得到所有 0