1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "TrustyGateKeeper"
18 
19 #include <errno.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24 
25 #include <log/log.h>
26 #include <trusty/tipc.h>
27 
28 #include "trusty_gatekeeper_ipc.h"
29 #include "gatekeeper_ipc.h"
30 
31 #define TRUSTY_DEVICE_NAME "/dev/trusty-ipc-dev0"
32 
33 static int handle_ = 0;
34 
trusty_gatekeeper_connect()35 int trusty_gatekeeper_connect() {
36     int rc = tipc_connect(TRUSTY_DEVICE_NAME, GATEKEEPER_PORT);
37     if (rc < 0) {
38         return rc;
39     }
40 
41     handle_ = rc;
42     return 0;
43 }
44 
trusty_gatekeeper_call(uint32_t cmd,void * in,uint32_t in_size,uint8_t * out,uint32_t * out_size)45 int trusty_gatekeeper_call(uint32_t cmd, void *in, uint32_t in_size, uint8_t *out,
46                            uint32_t *out_size) {
47     if (handle_ == 0) {
48         ALOGE("not connected\n");
49         return -EINVAL;
50     }
51 
52     size_t msg_size = in_size + sizeof(struct gatekeeper_message);
53     struct gatekeeper_message *msg = malloc(msg_size);
54     msg->cmd = cmd;
55     memcpy(msg->payload, in, in_size);
56 
57     ssize_t rc = write(handle_, msg, msg_size);
58     free(msg);
59 
60     if (rc < 0) {
61         ALOGE("failed to send cmd (%d) to %s: %s\n", cmd,
62                 GATEKEEPER_PORT, strerror(errno));
63         return -errno;
64     }
65 
66     rc = read(handle_, out, *out_size);
67     if (rc < 0) {
68         ALOGE("failed to retrieve response for cmd (%d) to %s: %s\n",
69                 cmd, GATEKEEPER_PORT, strerror(errno));
70         return -errno;
71     }
72 
73     if ((size_t) rc < sizeof(struct gatekeeper_message)) {
74         ALOGE("invalid response size (%d)\n", (int) rc);
75         return -EINVAL;
76     }
77 
78     msg = (struct gatekeeper_message *) out;
79 
80     if ((cmd | GK_RESP_BIT) != msg->cmd) {
81         ALOGE("invalid command (%d)\n", msg->cmd);
82         return -EINVAL;
83     }
84 
85     *out_size = ((size_t) rc) - sizeof(struct gatekeeper_message);
86     return rc;
87 }
88 
trusty_gatekeeper_disconnect()89 void trusty_gatekeeper_disconnect() {
90     if (handle_ != 0) {
91         tipc_close(handle_);
92     }
93 }
94 
95