service_manager.c revision 9066cfe9886ac131c34d59ed0e2d287b0e3c0087
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 { AID_MEDIA, "media.audio_flinger" }, 31 { AID_MEDIA, "media.player" }, 32 { AID_MEDIA, "media.camera" }, 33 { AID_RADIO, "radio.phone" }, 34 { AID_RADIO, "radio.sms" }, 35 { AID_RADIO, "radio.phonesubinfo" }, 36 { AID_RADIO, "radio.simphonebook" }, 37/* TODO: remove after phone services are updated: */ 38 { AID_RADIO, "phone" }, 39 { AID_RADIO, "isms" }, 40 { AID_RADIO, "iphonesubinfo" }, 41 { AID_RADIO, "simphonebook" }, 42}; 43 44void *svcmgr_handle; 45 46const char *str8(uint16_t *x) 47{ 48 static char buf[128]; 49 unsigned max = 127; 50 char *p = buf; 51 52 if (x) { 53 while (*x && max--) { 54 *p++ = *x++; 55 } 56 } 57 *p++ = 0; 58 return buf; 59} 60 61int str16eq(uint16_t *a, const char *b) 62{ 63 while (*a && *b) 64 if (*a++ != *b++) return 0; 65 if (*a || *b) 66 return 0; 67 return 1; 68} 69 70int svc_can_register(unsigned uid, uint16_t *name) 71{ 72 unsigned n; 73 74 if ((uid == 0) || (uid == AID_SYSTEM)) 75 return 1; 76 77 for (n = 0; n < sizeof(allowed) / sizeof(allowed[0]); n++) 78 if ((uid == allowed[n].uid) && str16eq(name, allowed[n].name)) 79 return 1; 80 81 return 0; 82} 83 84struct svcinfo 85{ 86 struct svcinfo *next; 87 void *ptr; 88 struct binder_death death; 89 unsigned len; 90 uint16_t name[0]; 91}; 92 93struct svcinfo *svclist = 0; 94 95struct svcinfo *find_svc(uint16_t *s16, unsigned len) 96{ 97 struct svcinfo *si; 98 99 for (si = svclist; si; si = si->next) { 100 if ((len == si->len) && 101 !memcmp(s16, si->name, len * sizeof(uint16_t))) { 102 return si; 103 } 104 } 105 return 0; 106} 107 108void svcinfo_death(struct binder_state *bs, void *ptr) 109{ 110 struct svcinfo *si = ptr; 111 LOGI("service '%s' died\n", str8(si->name)); 112 if (si->ptr) { 113 binder_release(bs, si->ptr); 114 si->ptr = 0; 115 } 116} 117 118uint16_t svcmgr_id[] = { 119 'a','n','d','r','o','i','d','.','o','s','.', 120 'I','S','e','r','v','i','c','e','M','a','n','a','g','e','r' 121}; 122 123 124void *do_find_service(struct binder_state *bs, uint16_t *s, unsigned len) 125{ 126 struct svcinfo *si; 127 si = find_svc(s, len); 128 129// LOGI("check_service('%s') ptr = %p\n", str8(s), si ? si->ptr : 0); 130 if (si && si->ptr) { 131 return si->ptr; 132 } else { 133 return 0; 134 } 135} 136 137int do_add_service(struct binder_state *bs, 138 uint16_t *s, unsigned len, 139 void *ptr, unsigned uid) 140{ 141 struct svcinfo *si; 142// LOGI("add_service('%s',%p) uid=%d\n", str8(s), ptr, uid); 143 144 if (!ptr || (len == 0) || (len > 127)) 145 return -1; 146 147 if (!svc_can_register(uid, s)) { 148 LOGE("add_service('%s',%p) uid=%d - PERMISSION DENIED\n", 149 str8(s), ptr, uid); 150 return -1; 151 } 152 153 si = find_svc(s, len); 154 if (si) { 155 if (si->ptr) { 156 LOGE("add_service('%s',%p) uid=%d - ALREADY REGISTERED\n", 157 str8(s), ptr, uid); 158 return -1; 159 } 160 si->ptr = ptr; 161 } else { 162 si = malloc(sizeof(*si) + (len + 1) * sizeof(uint16_t)); 163 if (!si) { 164 LOGE("add_service('%s',%p) uid=%d - OUT OF MEMORY\n", 165 str8(s), ptr, uid); 166 return -1; 167 } 168 si->ptr = ptr; 169 si->len = len; 170 memcpy(si->name, s, (len + 1) * sizeof(uint16_t)); 171 si->name[len] = '\0'; 172 si->death.func = svcinfo_death; 173 si->death.ptr = si; 174 si->next = svclist; 175 svclist = si; 176 } 177 178 binder_acquire(bs, ptr); 179 binder_link_to_death(bs, ptr, &si->death); 180 return 0; 181} 182 183int svcmgr_handler(struct binder_state *bs, 184 struct binder_txn *txn, 185 struct binder_io *msg, 186 struct binder_io *reply) 187{ 188 struct svcinfo *si; 189 uint16_t *s; 190 unsigned len; 191 void *ptr; 192 193// LOGI("target=%p code=%d pid=%d uid=%d\n", 194// txn->target, txn->code, txn->sender_pid, txn->sender_euid); 195 196 if (txn->target != svcmgr_handle) 197 return -1; 198 199 s = bio_get_string16(msg, &len); 200 201 if ((len != (sizeof(svcmgr_id) / 2)) || 202 memcmp(svcmgr_id, s, sizeof(svcmgr_id))) { 203 fprintf(stderr,"invalid id %s\n", str8(s)); 204 return -1; 205 } 206 207 switch(txn->code) { 208 case SVC_MGR_GET_SERVICE: 209 case SVC_MGR_CHECK_SERVICE: 210 s = bio_get_string16(msg, &len); 211 ptr = do_find_service(bs, s, len); 212 if (!ptr) 213 break; 214 bio_put_ref(reply, ptr); 215 return 0; 216 217 case SVC_MGR_ADD_SERVICE: 218 s = bio_get_string16(msg, &len); 219 ptr = bio_get_ref(msg); 220 if (do_add_service(bs, s, len, ptr, txn->sender_euid)) 221 return -1; 222 break; 223 224 case SVC_MGR_LIST_SERVICES: { 225 unsigned n = bio_get_uint32(msg); 226 227 si = svclist; 228 while ((n-- > 0) && si) 229 si = si->next; 230 if (si) { 231 bio_put_string16(reply, si->name); 232 return 0; 233 } 234 return -1; 235 } 236 default: 237 LOGE("unknown code %d\n", txn->code); 238 return -1; 239 } 240 241 bio_put_uint32(reply, 0); 242 return 0; 243} 244 245int main(int argc, char **argv) 246{ 247 struct binder_state *bs; 248 void *svcmgr = BINDER_SERVICE_MANAGER; 249 250 bs = binder_open(128*1024); 251 252 if (binder_become_context_manager(bs)) { 253 LOGE("cannot become context manager (%s)\n", strerror(errno)); 254 return -1; 255 } 256 257 svcmgr_handle = svcmgr; 258 binder_loop(bs, svcmgr_handler); 259 return 0; 260} 261