rild.c revision f423cde8f901a72fd0cb811583a2cdabe62c64bd 
1/* //device/system/rild/rild.c
2**
3** Copyright 2006, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18#include <stdio.h>
19#include <stdlib.h>
20#include <dlfcn.h>
21#include <string.h>
22#include <stdint.h>
23#include <unistd.h>
24#include <fcntl.h>
25#include <errno.h>
26
27#include <telephony/ril.h>
28#define LOG_TAG "RILD"
29#include <utils/Log.h>
30#include <cutils/properties.h>
31#include <cutils/sockets.h>
32#include <linux/capability.h>
33#include <linux/prctl.h>
34
35#include <private/android_filesystem_config.h>
36#include "hardware/qemu_pipe.h"
37
38#define LIB_PATH_PROPERTY   "rild.libpath"
39#define LIB_ARGS_PROPERTY   "rild.libargs"
40#define MAX_LIB_ARGS        16
41
42static void usage(const char *argv0)
43{
44    fprintf(stderr, "Usage: %s -l <ril impl library> [-- <args for impl library>]\n", argv0);
45    exit(-1);
46}
47
48extern void RIL_register (const RIL_RadioFunctions *callbacks);
49
50extern void RIL_onRequestComplete(RIL_Token t, RIL_Errno e,
51                           void *response, size_t responselen);
52
53extern void RIL_onUnsolicitedResponse(int unsolResponse, const void *data,
54                                size_t datalen);
55
56extern void RIL_requestTimedCallback (RIL_TimedCallback callback,
57                               void *param, const struct timeval *relativeTime);
58
59
60static struct RIL_Env s_rilEnv = {
61    RIL_onRequestComplete,
62    RIL_onUnsolicitedResponse,
63    RIL_requestTimedCallback
64};
65
66extern void RIL_startEventLoop();
67
68static int make_argv(char * args, char ** argv)
69{
70    // Note: reserve argv[0]
71    int count = 1;
72    char * tok;
73    char * s = args;
74
75    while ((tok = strtok(s, " \0"))) {
76        argv[count] = tok;
77        s = NULL;
78        count++;
79    }
80    return count;
81}
82
83/*
84 * switchUser - Switches UID to radio, preserving CAP_NET_ADMIN capabilities.
85 * Our group, cache, was set by init.
86 */
87void switchUser() {
88    prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0);
89    setuid(AID_RADIO);
90
91    struct __user_cap_header_struct header;
92    struct __user_cap_data_struct cap;
93    header.version = _LINUX_CAPABILITY_VERSION;
94    header.pid = 0;
95    cap.effective = cap.permitted = (1 << CAP_NET_ADMIN) | (1 << CAP_NET_RAW);
96    cap.inheritable = 0;
97    capset(&header, &cap);
98}
99
100int main(int argc, char **argv)
101{
102    const char * rilLibPath = NULL;
103    char **rilArgv;
104    void *dlHandle;
105    const RIL_RadioFunctions *(*rilInit)(const struct RIL_Env *, int, char **);
106    const RIL_RadioFunctions *funcs;
107    char libPath[PROPERTY_VALUE_MAX];
108    unsigned char hasLibArgs = 0;
109
110    int i;
111
112    umask(S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IWOTH | S_IXOTH);
113    for (i = 1; i < argc ;) {
114        if (0 == strcmp(argv[i], "-l") && (argc - i > 1)) {
115            rilLibPath = argv[i + 1];
116            i += 2;
117        } else if (0 == strcmp(argv[i], "--")) {
118            i++;
119            hasLibArgs = 1;
120            break;
121        } else {
122            usage(argv[0]);
123        }
124    }
125
126    if (rilLibPath == NULL) {
127        if ( 0 == property_get(LIB_PATH_PROPERTY, libPath, NULL)) {
128            // No lib sepcified on the command line, and nothing set in props.
129            // Assume "no-ril" case.
130            goto done;
131        } else {
132            rilLibPath = libPath;
133        }
134    }
135
136    /* special override when in the emulator */
137#if 1
138    {
139        static char*  arg_overrides[3];
140        static char   arg_device[32];
141        int           done = 0;
142
143#define  REFERENCE_RIL_PATH  "/system/lib/libreference-ril.so"
144
145        /* first, read /proc/cmdline into memory */
146        char          buffer[1024], *p, *q;
147        int           len;
148        int           fd = open("/proc/cmdline",O_RDONLY);
149
150        if (fd < 0) {
151            ALOGD("could not open /proc/cmdline:%s", strerror(errno));
152            goto OpenLib;
153        }
154
155        do {
156            len = read(fd,buffer,sizeof(buffer)); }
157        while (len == -1 && errno == EINTR);
158
159        if (len < 0) {
160            ALOGD("could not read /proc/cmdline:%s", strerror(errno));
161            close(fd);
162            goto OpenLib;
163        }
164        close(fd);
165
166        if (strstr(buffer, "android.qemud=") != NULL)
167        {
168            /* the qemud daemon is launched after rild, so
169            * give it some time to create its GSM socket
170            */
171            int  tries = 5;
172#define  QEMUD_SOCKET_NAME    "qemud"
173
174            while (1) {
175                int  fd;
176
177                sleep(1);
178
179                fd = qemu_pipe_open("qemud:gsm");
180                if (fd < 0) {
181                    fd = socket_local_client(
182                                QEMUD_SOCKET_NAME,
183                                ANDROID_SOCKET_NAMESPACE_RESERVED,
184                                SOCK_STREAM );
185                }
186                if (fd >= 0) {
187                    close(fd);
188                    snprintf( arg_device, sizeof(arg_device), "%s/%s",
189                                ANDROID_SOCKET_DIR, QEMUD_SOCKET_NAME );
190
191                    arg_overrides[1] = "-s";
192                    arg_overrides[2] = arg_device;
193                    done = 1;
194                    break;
195                }
196                ALOGD("could not connect to %s socket: %s",
197                    QEMUD_SOCKET_NAME, strerror(errno));
198                if (--tries == 0)
199                    break;
200            }
201            if (!done) {
202                ALOGE("could not connect to %s socket (giving up): %s",
203                    QEMUD_SOCKET_NAME, strerror(errno));
204                while(1)
205                    sleep(0x00ffffff);
206            }
207        }
208
209        /* otherwise, try to see if we passed a device name from the kernel */
210        if (!done) do {
211#define  KERNEL_OPTION  "android.ril="
212#define  DEV_PREFIX     "/dev/"
213
214            p = strstr( buffer, KERNEL_OPTION );
215            if (p == NULL)
216                break;
217
218            p += sizeof(KERNEL_OPTION)-1;
219            q  = strpbrk( p, " \t\n\r" );
220            if (q != NULL)
221                *q = 0;
222
223            snprintf( arg_device, sizeof(arg_device), DEV_PREFIX "%s", p );
224            arg_device[sizeof(arg_device)-1] = 0;
225            arg_overrides[1] = "-d";
226            arg_overrides[2] = arg_device;
227            done = 1;
228
229        } while (0);
230
231        if (done) {
232            argv = arg_overrides;
233            argc = 3;
234            i    = 1;
235            hasLibArgs = 1;
236            rilLibPath = REFERENCE_RIL_PATH;
237
238            ALOGD("overriding with %s %s", arg_overrides[1], arg_overrides[2]);
239        }
240    }
241OpenLib:
242#endif
243    switchUser();
244
245    dlHandle = dlopen(rilLibPath, RTLD_NOW);
246
247    if (dlHandle == NULL) {
248        fprintf(stderr, "dlopen failed: %s\n", dlerror());
249        exit(-1);
250    }
251
252    RIL_startEventLoop();
253
254    rilInit = (const RIL_RadioFunctions *(*)(const struct RIL_Env *, int, char **))dlsym(dlHandle, "RIL_Init");
255
256    if (rilInit == NULL) {
257        fprintf(stderr, "RIL_Init not defined or exported in %s\n", rilLibPath);
258        exit(-1);
259    }
260
261    if (hasLibArgs) {
262        rilArgv = argv + i - 1;
263        argc = argc -i + 1;
264    } else {
265        static char * newArgv[MAX_LIB_ARGS];
266        static char args[PROPERTY_VALUE_MAX];
267        rilArgv = newArgv;
268        property_get(LIB_ARGS_PROPERTY, args, "");
269        argc = make_argv(args, rilArgv);
270    }
271
272    // Make sure there's a reasonable argv[0]
273    rilArgv[0] = argv[0];
274
275    funcs = rilInit(&s_rilEnv, argc, rilArgv);
276
277    RIL_register(funcs);
278
279done:
280
281    while(1) {
282        // sleep(UINT32_MAX) seems to return immediately on bionic
283        sleep(0x00ffffff);
284    }
285}
286
287