1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <unistd.h>
7#include <errno.h>
8#include <string.h>
9#include <sys/wait.h>
10#include <net_user.h>
11#include <os.h>
12#include "slirp.h"
13
14static int slirp_user_init(void *data, void *dev)
15{
16	struct slirp_data *pri = data;
17
18	pri->dev = dev;
19	return 0;
20}
21
22struct slirp_pre_exec_data {
23	int stdin_fd;
24	int stdout_fd;
25};
26
27static void slirp_pre_exec(void *arg)
28{
29	struct slirp_pre_exec_data *data = arg;
30
31	if (data->stdin_fd != -1)
32		dup2(data->stdin_fd, 0);
33	if (data->stdout_fd != -1)
34		dup2(data->stdout_fd, 1);
35}
36
37static int slirp_tramp(char **argv, int fd)
38{
39	struct slirp_pre_exec_data pe_data;
40	int pid;
41
42	pe_data.stdin_fd = fd;
43	pe_data.stdout_fd = fd;
44	pid = run_helper(slirp_pre_exec, &pe_data, argv);
45
46	return pid;
47}
48
49static int slirp_open(void *data)
50{
51	struct slirp_data *pri = data;
52	int fds[2], pid, err;
53
54	err = os_pipe(fds, 1, 1);
55	if (err)
56		return err;
57
58	err = slirp_tramp(pri->argw.argv, fds[1]);
59	if (err < 0) {
60		printk(UM_KERN_ERR "slirp_tramp failed - errno = %d\n", -err);
61		goto out;
62	}
63	pid = err;
64
65	pri->slave = fds[1];
66	pri->slip.pos = 0;
67	pri->slip.esc = 0;
68	pri->pid = err;
69
70	return fds[0];
71out:
72	close(fds[0]);
73	close(fds[1]);
74	return err;
75}
76
77static void slirp_close(int fd, void *data)
78{
79	struct slirp_data *pri = data;
80	int err;
81
82	close(fd);
83	close(pri->slave);
84
85	pri->slave = -1;
86
87	if (pri->pid<1) {
88		printk(UM_KERN_ERR "slirp_close: no child process to shut "
89		       "down\n");
90		return;
91	}
92
93#if 0
94	if (kill(pri->pid, SIGHUP)<0) {
95		printk(UM_KERN_ERR "slirp_close: sending hangup to %d failed "
96		       "(%d)\n", pri->pid, errno);
97	}
98#endif
99	err = helper_wait(pri->pid);
100	if (err < 0)
101		return;
102
103	pri->pid = -1;
104}
105
106int slirp_user_read(int fd, void *buf, int len, struct slirp_data *pri)
107{
108	return slip_proto_read(fd, buf, len, &pri->slip);
109}
110
111int slirp_user_write(int fd, void *buf, int len, struct slirp_data *pri)
112{
113	return slip_proto_write(fd, buf, len, &pri->slip);
114}
115
116const struct net_user_info slirp_user_info = {
117	.init		= slirp_user_init,
118	.open		= slirp_open,
119	.close	 	= slirp_close,
120	.remove	 	= NULL,
121	.add_address	= NULL,
122	.delete_address = NULL,
123	.mtu		= BUF_SIZE,
124	.max_packet	= BUF_SIZE,
125};
126