service_manager.c revision cd0e839a2448deea50f79bddeba782c546b33893
1/* Copyright 2008 The Android Open Source Project 2 */ 3 4#include <stdio.h> 5#include <stdlib.h> 6#include <errno.h> 7#include <fcntl.h> 8 9#include <private/android_filesystem_config.h> 10 11#include "binder.h" 12 13#if 0 14#define LOGI(x...) fprintf(stderr, "svcmgr: " x) 15#define LOGE(x...) fprintf(stderr, "svcmgr: " x) 16#else 17#define LOG_TAG "ServiceManager" 18#include <cutils/log.h> 19#endif 20 21/* TODO: 22 * These should come from a config file or perhaps be 23 * based on some namespace rules of some sort (media 24 * uid can register media.*, etc) 25 */ 26static struct { 27 unsigned uid; 28 const char *name; 29} allowed[] = { 30#ifdef LVMX 31 { AID_MEDIA, "com.lifevibes.mx.ipc" }, 32#endif 33 { AID_MEDIA, "media.audio_flinger" }, 34 { AID_MEDIA, "media.player" }, 35 { AID_MEDIA, "media.camera" }, 36 { AID_MEDIA, "media.audio_policy" }, 37 { AID_DRMIO, "drm.drmIOService" }, 38 { AID_DRM, "drm.drmManager" }, 39 { AID_NFC, "nfc" }, 40 { AID_RADIO, "radio.phone" }, 41 { AID_RADIO, "radio.sms" }, 42 { AID_RADIO, "radio.phonesubinfo" }, 43 { AID_RADIO, "radio.simphonebook" }, 44/* TODO: remove after phone services are updated: */ 45 { AID_RADIO, "phone" }, 46 { AID_RADIO, "sip" }, 47 { AID_RADIO, "isms" }, 48 { AID_RADIO, "iphonesubinfo" }, 49 { AID_RADIO, "simphonebook" }, 50}; 51 52void *svcmgr_handle; 53 54const char *str8(uint16_t *x) 55{ 56 static char buf[128]; 57 unsigned max = 127; 58 char *p = buf; 59 60 if (x) { 61 while (*x && max--) { 62 *p++ = *x++; 63 } 64 } 65 *p++ = 0; 66 return buf; 67} 68 69int str16eq(uint16_t *a, const char *b) 70{ 71 while (*a && *b) 72 if (*a++ != *b++) return 0; 73 if (*a || *b) 74 return 0; 75 return 1; 76} 77 78int svc_can_register(unsigned uid, uint16_t *name) 79{ 80 unsigned n; 81 82 if ((uid == 0) || (uid == AID_SYSTEM)) 83 return 1; 84 85 for (n = 0; n < sizeof(allowed) / sizeof(allowed[0]); n++) 86 if ((uid == allowed[n].uid) && str16eq(name, allowed[n].name)) 87 return 1; 88 89 return 0; 90} 91 92struct svcinfo 93{ 94 struct svcinfo *next; 95 void *ptr; 96 struct binder_death death; 97 unsigned len; 98 uint16_t name[0]; 99}; 100 101struct svcinfo *svclist = 0; 102 103struct svcinfo *find_svc(uint16_t *s16, unsigned len) 104{ 105 struct svcinfo *si; 106 107 for (si = svclist; si; si = si->next) { 108 if ((len == si->len) && 109 !memcmp(s16, si->name, len * sizeof(uint16_t))) { 110 return si; 111 } 112 } 113 return 0; 114} 115 116void svcinfo_death(struct binder_state *bs, void *ptr) 117{ 118 struct svcinfo *si = ptr; 119 LOGI("service '%s' died\n", str8(si->name)); 120 if (si->ptr) { 121 binder_release(bs, si->ptr); 122 si->ptr = 0; 123 } 124} 125 126uint16_t svcmgr_id[] = { 127 'a','n','d','r','o','i','d','.','o','s','.', 128 'I','S','e','r','v','i','c','e','M','a','n','a','g','e','r' 129}; 130 131 132void *do_find_service(struct binder_state *bs, uint16_t *s, unsigned len) 133{ 134 struct svcinfo *si; 135 si = find_svc(s, len); 136 137// LOGI("check_service('%s') ptr = %p\n", str8(s), si ? si->ptr : 0); 138 if (si && si->ptr) { 139 return si->ptr; 140 } else { 141 return 0; 142 } 143} 144 145int do_add_service(struct binder_state *bs, 146 uint16_t *s, unsigned len, 147 void *ptr, unsigned uid) 148{ 149 struct svcinfo *si; 150// LOGI("add_service('%s',%p) uid=%d\n", str8(s), ptr, uid); 151 152 if (!ptr || (len == 0) || (len > 127)) 153 return -1; 154 155 if (!svc_can_register(uid, s)) { 156 LOGE("add_service('%s',%p) uid=%d - PERMISSION DENIED\n", 157 str8(s), ptr, uid); 158 return -1; 159 } 160 161 si = find_svc(s, len); 162 if (si) { 163 if (si->ptr) { 164 LOGE("add_service('%s',%p) uid=%d - ALREADY REGISTERED\n", 165 str8(s), ptr, uid); 166 return -1; 167 } 168 si->ptr = ptr; 169 } else { 170 si = malloc(sizeof(*si) + (len + 1) * sizeof(uint16_t)); 171 if (!si) { 172 LOGE("add_service('%s',%p) uid=%d - OUT OF MEMORY\n", 173 str8(s), ptr, uid); 174 return -1; 175 } 176 si->ptr = ptr; 177 si->len = len; 178 memcpy(si->name, s, (len + 1) * sizeof(uint16_t)); 179 si->name[len] = '\0'; 180 si->death.func = svcinfo_death; 181 si->death.ptr = si; 182 si->next = svclist; 183 svclist = si; 184 } 185 186 binder_acquire(bs, ptr); 187 binder_link_to_death(bs, ptr, &si->death); 188 return 0; 189} 190 191int svcmgr_handler(struct binder_state *bs, 192 struct binder_txn *txn, 193 struct binder_io *msg, 194 struct binder_io *reply) 195{ 196 struct svcinfo *si; 197 uint16_t *s; 198 unsigned len; 199 void *ptr; 200 uint32_t strict_policy; 201 202// LOGI("target=%p code=%d pid=%d uid=%d\n", 203// txn->target, txn->code, txn->sender_pid, txn->sender_euid); 204 205 if (txn->target != svcmgr_handle) 206 return -1; 207 208 // Equivalent to Parcel::enforceInterface(), reading the RPC 209 // header with the strict mode policy mask and the interface name. 210 // Note that we ignore the strict_policy and don't propagate it 211 // further (since we do no outbound RPCs anyway). 212 strict_policy = bio_get_uint32(msg); 213 s = bio_get_string16(msg, &len); 214 if ((len != (sizeof(svcmgr_id) / 2)) || 215 memcmp(svcmgr_id, s, sizeof(svcmgr_id))) { 216 fprintf(stderr,"invalid id %s\n", str8(s)); 217 return -1; 218 } 219 220 switch(txn->code) { 221 case SVC_MGR_GET_SERVICE: 222 case SVC_MGR_CHECK_SERVICE: 223 s = bio_get_string16(msg, &len); 224 ptr = do_find_service(bs, s, len); 225 if (!ptr) 226 break; 227 bio_put_ref(reply, ptr); 228 return 0; 229 230 case SVC_MGR_ADD_SERVICE: 231 s = bio_get_string16(msg, &len); 232 ptr = bio_get_ref(msg); 233 if (do_add_service(bs, s, len, ptr, txn->sender_euid)) 234 return -1; 235 break; 236 237 case SVC_MGR_LIST_SERVICES: { 238 unsigned n = bio_get_uint32(msg); 239 240 si = svclist; 241 while ((n-- > 0) && si) 242 si = si->next; 243 if (si) { 244 bio_put_string16(reply, si->name); 245 return 0; 246 } 247 return -1; 248 } 249 default: 250 LOGE("unknown code %d\n", txn->code); 251 return -1; 252 } 253 254 bio_put_uint32(reply, 0); 255 return 0; 256} 257 258int main(int argc, char **argv) 259{ 260 struct binder_state *bs; 261 void *svcmgr = BINDER_SERVICE_MANAGER; 262 263 bs = binder_open(128*1024); 264 265 if (binder_become_context_manager(bs)) { 266 LOGE("cannot become context manager (%s)\n", strerror(errno)); 267 return -1; 268 } 269 270 svcmgr_handle = svcmgr; 271 binder_loop(bs, svcmgr_handler); 272 return 0; 273} 274