xref: /f-stack/tools/compat/ioctl.c (revision b9e91cfd)
1 /*
2  * Copyright (C) 2017 THL A29 Limited, a Tencent company.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright notice, this
9  *   list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright notice,
11  *   this list of conditions and the following disclaimer in the documentation
12  *   and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
18  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
21  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
23  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  */
26 
27 #include <string.h>
28 #include <stdarg.h>
29 #include <sys/socket.h>
30 #include <sys/ioctl.h>
31 #include "ff_ipc.h"
32 
33 /*
34  * In general, we always call like this: ioctl(fd, com, data),
35  * but if there is a pointer in the data and the pointer points to
36  * a memory area, for example, data is struct ifreq, and it uses
37  * ifreq.ifr_ifru.ifru_data, we must copy the memory to msg->buf_addr,
38  * after this, it can be used to communicate with F-Stack process.
39  * Otherwise, an unknown error will occur.
40  *
41  * Two cases:
42  * 1.Normal, there is no need to copy memory: ioctl_va(fd, com, data, 0).
43  * 2.There is a memory need to be copied: ioctl_va(fd, com, data, 3, offset, cpy_mem, clen).
44  *     offset: the offset of cpy_mem relative to data struct.
45  *     cpy_mem: the memory address that need to be copied.
46  *     clen: the size of memory that the cpy_mem pointed to.
47  *
48  */
49 int
50 ioctl_va(int fd, unsigned long com, void *data, int argc, ...)
51 {
52     struct ff_msg *msg, *retmsg = NULL;
53     unsigned size;
54     void *cpy_mem;
55     size_t offset, clen;
56 
57     if (argc != 0 && argc != 3) {
58         errno = EINVAL;
59         return -1;
60     }
61 
62     if (argc == 3) {
63         va_list ap;
64         va_start(ap, argc);
65         offset = va_arg(ap, size_t);
66         cpy_mem = va_arg(ap, void *);
67         clen = va_arg(ap, size_t);
68         va_end(ap);
69     }
70 
71     if (com > 0xffffffff) {
72         printf("WARNING: ioctl sign-extension ioctl %lx\n", com);
73         com &= 0xffffffff;
74     }
75 
76     size = IOCPARM_LEN(com);
77     if ((size > IOCPARM_MAX) ||
78         ((com & (IOC_IN | IOC_OUT)) == 0) ||
79         (size == 0) ||
80         (com & IOC_VOID))
81         return (ENOTTY);
82 
83     msg = ff_ipc_msg_alloc();
84     if (msg == NULL) {
85         errno = ENOMEM;
86         return -1;
87     }
88 
89     if (size > msg->buf_len) {
90         errno = ENOMEM;
91         ff_ipc_msg_free(msg);
92         return -1;
93     }
94 
95     msg->msg_type = FF_IOCTL;
96     msg->ioctl.cmd = com;
97     msg->ioctl.data = msg->buf_addr;
98     memcpy(msg->ioctl.data, data, size);
99     msg->buf_addr += size;
100 
101     if (argc == 3) {
102         if (size + clen > msg->buf_len) {
103             errno = ENOMEM;
104             ff_ipc_msg_free(msg);
105             return -1;
106         }
107         char *ptr = (char *)(msg->ioctl.data) + offset;
108         char *buf_addr = msg->buf_addr;
109         memcpy(ptr, &buf_addr, sizeof(char *));
110         memcpy(buf_addr, cpy_mem, clen);
111     }
112 
113     int ret = ff_ipc_send(msg);
114     if (ret < 0) {
115         errno = EPIPE;
116         ff_ipc_msg_free(msg);
117         return -1;
118     }
119 
120     do {
121         if (retmsg != NULL) {
122             ff_ipc_msg_free(retmsg);
123         }
124         ret = ff_ipc_recv(&retmsg);
125         if (ret < 0) {
126             errno = EPIPE;
127             ff_ipc_msg_free(msg);
128             return -1;
129         }
130     } while (msg != retmsg);
131 
132     if (retmsg->result == 0) {
133         ret = 0;
134 
135         if (com & IOC_OUT) {
136             memcpy(data, retmsg->ioctl.data, size);
137             if (argc == 3) {
138                 memcpy(cpy_mem, retmsg->buf_addr, clen);
139                 char *ptr = (char *)data + offset;
140                 memcpy(ptr, &cpy_mem, sizeof(void *));
141             }
142         }
143     } else {
144         ret = -1;
145         errno = retmsg->result;
146     }
147 
148     ff_ipc_msg_free(msg);
149 
150     return ret;
151 }
152 
153