/* Copyright 2008 The Android Open Source Project */ #include #include #include #include #include #include "binder.h" #if 0 #define ALOGI(x...) fprintf(stderr, "svcmgr: " x) #define ALOGE(x...) fprintf(stderr, "svcmgr: " x) #else #define LOG_TAG "ServiceManager" #include #endif /* TODO: * These should come from a config file or perhaps be * based on some namespace rules of some sort (media * uid can register media.*, etc) */ static struct { uid_t uid; const char *name; } allowed[] = { { AID_MEDIA, "media.audio_flinger" }, { AID_MEDIA, "media.log" }, { AID_MEDIA, "media.player" }, { AID_MEDIA, "media.camera" }, { AID_MEDIA, "media.audio_policy" }, { AID_DRM, "drm.drmManager" }, { AID_NFC, "nfc" }, { AID_BLUETOOTH, "bluetooth" }, { AID_RADIO, "radio.phone" }, { AID_RADIO, "radio.sms" }, { AID_RADIO, "radio.phonesubinfo" }, { AID_RADIO, "radio.simphonebook" }, /* TODO: remove after phone services are updated: */ { AID_RADIO, "phone" }, { AID_RADIO, "sip" }, { AID_RADIO, "isms" }, { AID_RADIO, "iphonesubinfo" }, { AID_RADIO, "simphonebook" }, { AID_MEDIA, "common_time.clock" }, { AID_MEDIA, "common_time.config" }, { AID_KEYSTORE, "android.security.keystore" }, }; uint32_t svcmgr_handle; const char *str8(const uint16_t *x) { static char buf[128]; unsigned max = 127; char *p = buf; if (x) { while (*x && max--) { *p++ = *x++; } } *p++ = 0; return buf; } int str16eq(const uint16_t *a, const char *b) { while (*a && *b) if (*a++ != *b++) return 0; if (*a || *b) return 0; return 1; } int svc_can_register(uid_t uid, const uint16_t *name) { size_t n; if ((uid == 0) || (uid == AID_SYSTEM)) return 1; for (n = 0; n < sizeof(allowed) / sizeof(allowed[0]); n++) if ((uid == allowed[n].uid) && str16eq(name, allowed[n].name)) return 1; return 0; } struct svcinfo { struct svcinfo *next; uint32_t handle; struct binder_death death; int allow_isolated; size_t len; uint16_t name[0]; }; struct svcinfo *svclist = NULL; struct svcinfo *find_svc(const uint16_t *s16, size_t len) { struct svcinfo *si; for (si = svclist; si; si = si->next) { if ((len == si->len) && !memcmp(s16, si->name, len * sizeof(uint16_t))) { return si; } } return NULL; } void svcinfo_death(struct binder_state *bs, void *ptr) { struct svcinfo *si = (struct svcinfo* ) ptr; ALOGI("service '%s' died\n", str8(si->name)); if (si->handle) { binder_release(bs, si->handle); si->handle = 0; } } uint16_t svcmgr_id[] = { 'a','n','d','r','o','i','d','.','o','s','.', 'I','S','e','r','v','i','c','e','M','a','n','a','g','e','r' }; uint32_t do_find_service(struct binder_state *bs, const uint16_t *s, size_t len, uid_t uid) { struct svcinfo *si; si = find_svc(s, len); //ALOGI("check_service('%s') handle = %x\n", str8(s), si ? si->handle : 0); if (si && si->handle) { if (!si->allow_isolated) { // If this service doesn't allow access from isolated processes, // then check the uid to see if it is isolated. uid_t appid = uid % AID_USER; if (appid >= AID_ISOLATED_START && appid <= AID_ISOLATED_END) { return 0; } } return si->handle; } else { return 0; } } int do_add_service(struct binder_state *bs, const uint16_t *s, size_t len, uint32_t handle, uid_t uid, int allow_isolated) { struct svcinfo *si; //ALOGI("add_service('%s',%x,%s) uid=%d\n", str8(s), handle, // allow_isolated ? "allow_isolated" : "!allow_isolated", uid); if (!handle || (len == 0) || (len > 127)) return -1; if (!svc_can_register(uid, s)) { ALOGE("add_service('%s',%x) uid=%d - PERMISSION DENIED\n", str8(s), handle, uid); return -1; } si = find_svc(s, len); if (si) { if (si->handle) { ALOGE("add_service('%s',%x) uid=%d - ALREADY REGISTERED, OVERRIDE\n", str8(s), handle, uid); svcinfo_death(bs, si); } si->handle = handle; } else { si = malloc(sizeof(*si) + (len + 1) * sizeof(uint16_t)); if (!si) { ALOGE("add_service('%s',%x) uid=%d - OUT OF MEMORY\n", str8(s), handle, uid); return -1; } si->handle = handle; si->len = len; memcpy(si->name, s, (len + 1) * sizeof(uint16_t)); si->name[len] = '\0'; si->death.func = (void*) svcinfo_death; si->death.ptr = si; si->allow_isolated = allow_isolated; si->next = svclist; svclist = si; } binder_acquire(bs, handle); binder_link_to_death(bs, handle, &si->death); return 0; } int svcmgr_handler(struct binder_state *bs, struct binder_transaction_data *txn, struct binder_io *msg, struct binder_io *reply) { struct svcinfo *si; uint16_t *s; size_t len; uint32_t handle; uint32_t strict_policy; int allow_isolated; //ALOGI("target=%x code=%d pid=%d uid=%d\n", // txn->target.handle, txn->code, txn->sender_pid, txn->sender_euid); if (txn->target.handle != svcmgr_handle) return -1; if (txn->code == PING_TRANSACTION) return 0; // Equivalent to Parcel::enforceInterface(), reading the RPC // header with the strict mode policy mask and the interface name. // Note that we ignore the strict_policy and don't propagate it // further (since we do no outbound RPCs anyway). strict_policy = bio_get_uint32(msg); s = bio_get_string16(msg, &len); if ((len != (sizeof(svcmgr_id) / 2)) || memcmp(svcmgr_id, s, sizeof(svcmgr_id))) { fprintf(stderr,"invalid id %s\n", str8(s)); return -1; } switch(txn->code) { case SVC_MGR_GET_SERVICE: case SVC_MGR_CHECK_SERVICE: s = bio_get_string16(msg, &len); handle = do_find_service(bs, s, len, txn->sender_euid); if (!handle) break; bio_put_ref(reply, handle); return 0; case SVC_MGR_ADD_SERVICE: s = bio_get_string16(msg, &len); handle = bio_get_ref(msg); allow_isolated = bio_get_uint32(msg) ? 1 : 0; if (do_add_service(bs, s, len, handle, txn->sender_euid, allow_isolated)) return -1; break; case SVC_MGR_LIST_SERVICES: { uint32_t n = bio_get_uint32(msg); si = svclist; while ((n-- > 0) && si) si = si->next; if (si) { bio_put_string16(reply, si->name); return 0; } return -1; } default: ALOGE("unknown code %d\n", txn->code); return -1; } bio_put_uint32(reply, 0); return 0; } int main(int argc, char **argv) { struct binder_state *bs; bs = binder_open(128*1024); if (!bs) { ALOGE("failed to open binder driver\n"); return -1; } if (binder_become_context_manager(bs)) { ALOGE("cannot become context manager (%s)\n", strerror(errno)); return -1; } svcmgr_handle = BINDER_SERVICE_MANAGER; binder_loop(bs, svcmgr_handler); return 0; }