/
privpar.cpp
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privpar.cpp
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#include "privpar.h"
#include "ftpdIPC.h"
#include "sysutil.h"
PrivPar::PrivPar():parseconfig(ParseConfig::getInstance())
{
}
/**
* 本函数供父进程使用，将root进程设为nobody进程
*/
void minimize_privace()
{
struct passwd* pw = getpwnam("nobody");
if(pw == NULL)
FTPD_LOG(ERROR,"getpw error");
if(setegid(pw->pw_gid) == -1)
FTPD_LOG(ERROR,"setegid error");
if(seteuid(pw->pw_uid) == -1)
FTPD_LOG(ERROR,"seteuid error");
struct __user_cap_header_struct cap_header;
struct __user_cap_data_struct cap_data;
memset(&cap_header, 0, sizeof(cap_header));
memset(&cap_data, 0, sizeof(cap_data));
cap_header.version = _LINUX_CAPABILITY_VERSION_1;
cap_header.pid = 0;
__u32 cap_mask = 0; //设置权限
cap_mask |= (1 << CAP_NET_BIND_SERVICE); //获得绑定端口的权限
cap_data.effective = cap_data.permitted = cap_mask;
cap_data.inheritable = 0; //不能被继承
capset(&cap_header, &cap_data);
}
void PrivPar::handle_parent(session_t *sess)
{
minimize_privace();
char cmd;
while (1)
{
cmd = priv_sock_get_cmd(sess->parent_fd);
// 处理内部命令
switch (cmd)
{
case PRIV_SOCK_GET_DATA_SOCK:
privop_pasv_get_data_sock(sess);
break;
case PRIV_SOCK_PASV_ACTIVE:
privop_pasv_active(sess);
break;
case PRIV_SOCK_PASV_LISTEN:
privop_pasv_listen(sess);
break;
case PRIV_SOCK_PASV_ACCEPT:
privop_pasv_accept(sess);
break;
}
}
}
/**
* 创建数据连接通道
* @param sess [description]
*/
void PrivPar::privop_pasv_get_data_sock(session_t *sess)
{
/*
nobody进程接收PRIV_SOCK_GET_DATA_SOCK命令
进一步接收一个整数，也就是port
接收一个字符串，也就是ip
fd = socket
bind(20)
connect(ip, port);
OK
send_fd
BAD
*/
unsigned short port = (unsigned short)priv_sock_get_int(sess->parent_fd);
char ip[16] = {0};
priv_sock_recv_buf(sess->parent_fd, ip, sizeof(ip));
//从ftp服务进程获取IP地址
struct sockaddr_in addr;
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = inet_addr(ip);
int fd = sysutil::tcp_client(20);
if (fd == -1)
{
priv_sock_send_result(sess->parent_fd, PRIV_SOCK_RESULT_BAD);
return;
}
if (sysutil::connect_timeout(fd, &addr, parseconfig->get_accept_timeout()) < 0)
{
close(fd);
priv_sock_send_result(sess->parent_fd, PRIV_SOCK_RESULT_BAD);
return;
}
priv_sock_send_result(sess->parent_fd, PRIV_SOCK_RESULT_OK);
priv_sock_send_fd(sess->parent_fd, fd);
close(fd);
}
void PrivPar::privop_pasv_active(session_t *sess)
{
int active;
if (sess->pasv_listen_fd != -1)
{
active = 1;
}
else
{
active = 0;
}
priv_sock_send_int(sess->parent_fd, active);
}
void PrivPar::privop_pasv_listen(session_t *sess)
{
char ip[16] = {0};
sysutil::getlocalip(ip);
sess->pasv_listen_fd = sysutil::tcp_server(ip, 0);
struct sockaddr_in addr;
socklen_t addrlen = sizeof(addr);
if (getsockname(sess->pasv_listen_fd, (struct sockaddr *)&addr, &addrlen) < 0)
{
ERR_EXIT("getsockname");
}
unsigned short port = ntohs(addr.sin_port);
priv_sock_send_int(sess->parent_fd, (int)port);
}
void PrivPar::privop_pasv_accept(session_t *sess)
{
int fd = sysutil::accept_timeout(sess->pasv_listen_fd, NULL, parseconfig->get_accept_timeout());
close(sess->pasv_listen_fd);
sess->pasv_listen_fd = -1;
if (fd == -1)
{
priv_sock_send_result(sess->parent_fd, PRIV_SOCK_RESULT_BAD);
return;
}
priv_sock_send_result(sess->parent_fd, PRIV_SOCK_RESULT_OK);
priv_sock_send_fd(sess->parent_fd, fd);
close(fd);
}