1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com) |
4 | */ |
5 | |
6 | #include <stdio.h> |
7 | #include <stdlib.h> |
8 | #include <string.h> |
9 | #include <errno.h> |
10 | #include <termios.h> |
11 | #include <unistd.h> |
12 | #include <netinet/in.h> |
13 | #include "chan_user.h" |
14 | #include <os.h> |
15 | #include "port.h" |
16 | #include <um_malloc.h> |
17 | |
18 | struct port_chan { |
19 | int raw; |
20 | struct termios tt; |
21 | void *kernel_data; |
22 | char dev[sizeof("32768\0" )]; |
23 | }; |
24 | |
25 | static void *port_init(char *str, int device, const struct chan_opts *opts) |
26 | { |
27 | struct port_chan *data; |
28 | void *kern_data; |
29 | char *end; |
30 | int port; |
31 | |
32 | if (*str != ':') { |
33 | printk(UM_KERN_ERR "port_init : channel type 'port' must " |
34 | "specify a port number\n" ); |
35 | return NULL; |
36 | } |
37 | str++; |
38 | port = strtoul(str, &end, 0); |
39 | if ((*end != '\0') || (end == str)) { |
40 | printk(UM_KERN_ERR "port_init : couldn't parse port '%s'\n" , |
41 | str); |
42 | return NULL; |
43 | } |
44 | |
45 | kern_data = port_data(port); |
46 | if (kern_data == NULL) |
47 | return NULL; |
48 | |
49 | data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL); |
50 | if (data == NULL) |
51 | goto err; |
52 | |
53 | *data = ((struct port_chan) { .raw = opts->raw, |
54 | .kernel_data = kern_data }); |
55 | sprintf(data->dev, "%d" , port); |
56 | |
57 | return data; |
58 | err: |
59 | port_kern_free(d: kern_data); |
60 | return NULL; |
61 | } |
62 | |
63 | static void port_free(void *d) |
64 | { |
65 | struct port_chan *data = d; |
66 | |
67 | port_kern_free(d: data->kernel_data); |
68 | kfree(data); |
69 | } |
70 | |
71 | static int port_open(int input, int output, int primary, void *d, |
72 | char **dev_out) |
73 | { |
74 | struct port_chan *data = d; |
75 | int fd, err; |
76 | |
77 | fd = port_wait(data: data->kernel_data); |
78 | if ((fd >= 0) && data->raw) { |
79 | CATCH_EINTR(err = tcgetattr(fd, &data->tt)); |
80 | if (err) |
81 | return err; |
82 | |
83 | err = raw(fd); |
84 | if (err) |
85 | return err; |
86 | } |
87 | *dev_out = data->dev; |
88 | return fd; |
89 | } |
90 | |
91 | static void port_close(int fd, void *d) |
92 | { |
93 | struct port_chan *data = d; |
94 | |
95 | port_remove_dev(d: data->kernel_data); |
96 | os_close_file(fd); |
97 | } |
98 | |
99 | const struct chan_ops port_ops = { |
100 | .type = "port" , |
101 | .init = port_init, |
102 | .open = port_open, |
103 | .close = port_close, |
104 | .read = generic_read, |
105 | .write = generic_write, |
106 | .console_write = generic_console_write, |
107 | .window_size = generic_window_size, |
108 | .free = port_free, |
109 | .winch = 1, |
110 | }; |
111 | |
112 | int port_listen_fd(int port) |
113 | { |
114 | struct sockaddr_in addr; |
115 | int fd, err, arg; |
116 | |
117 | fd = socket(PF_INET, SOCK_STREAM, 0); |
118 | if (fd == -1) |
119 | return -errno; |
120 | |
121 | arg = 1; |
122 | if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &arg, sizeof(arg)) < 0) { |
123 | err = -errno; |
124 | goto out; |
125 | } |
126 | |
127 | addr.sin_family = AF_INET; |
128 | addr.sin_port = htons(port); |
129 | addr.sin_addr.s_addr = htonl(INADDR_ANY); |
130 | if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { |
131 | err = -errno; |
132 | goto out; |
133 | } |
134 | |
135 | if (listen(fd, 1) < 0) { |
136 | err = -errno; |
137 | goto out; |
138 | } |
139 | |
140 | err = os_set_fd_block(fd, 0); |
141 | if (err < 0) |
142 | goto out; |
143 | |
144 | return fd; |
145 | out: |
146 | close(fd); |
147 | return err; |
148 | } |
149 | |
150 | struct port_pre_exec_data { |
151 | int sock_fd; |
152 | int pipe_fd; |
153 | }; |
154 | |
155 | static void port_pre_exec(void *arg) |
156 | { |
157 | struct port_pre_exec_data *data = arg; |
158 | |
159 | dup2(data->sock_fd, 0); |
160 | dup2(data->sock_fd, 1); |
161 | dup2(data->sock_fd, 2); |
162 | close(data->sock_fd); |
163 | dup2(data->pipe_fd, 3); |
164 | shutdown(3, SHUT_RD); |
165 | close(data->pipe_fd); |
166 | } |
167 | |
168 | int port_connection(int fd, int *socket, int *pid_out) |
169 | { |
170 | int new, err; |
171 | char *env; |
172 | char *argv[] = { "in.telnetd" , "-L" , |
173 | OS_LIB_PATH "/uml/port-helper" , NULL }; |
174 | struct port_pre_exec_data data; |
175 | |
176 | if ((env = getenv("UML_PORT_HELPER" ))) |
177 | argv[2] = env; |
178 | |
179 | new = accept(fd, NULL, 0); |
180 | if (new < 0) |
181 | return -errno; |
182 | |
183 | err = os_access(argv[2], X_OK); |
184 | if (err < 0) { |
185 | printk(UM_KERN_ERR "port_connection : error accessing port-helper " |
186 | "executable at %s: %s\n" , argv[2], strerror(-err)); |
187 | if (env == NULL) |
188 | printk(UM_KERN_ERR "Set UML_PORT_HELPER environment " |
189 | "variable to path to uml-utilities port-helper " |
190 | "binary\n" ); |
191 | goto out_close; |
192 | } |
193 | |
194 | err = os_pipe(socket, 0, 0); |
195 | if (err < 0) |
196 | goto out_close; |
197 | |
198 | data = ((struct port_pre_exec_data) |
199 | { .sock_fd = new, |
200 | .pipe_fd = socket[1] }); |
201 | |
202 | err = run_helper(port_pre_exec, &data, argv); |
203 | if (err < 0) |
204 | goto out_shutdown; |
205 | |
206 | *pid_out = err; |
207 | return new; |
208 | |
209 | out_shutdown: |
210 | shutdown(socket[0], SHUT_RDWR); |
211 | close(socket[0]); |
212 | shutdown(socket[1], SHUT_RDWR); |
213 | close(socket[1]); |
214 | out_close: |
215 | close(new); |
216 | return err; |
217 | } |
218 | |