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/* Copyright 2008 The Android Open Source Project
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <private/android_filesystem_config.h>
#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 <cutils/log.h>
#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 {
unsigned uid;
const char *name;
} allowed[] = {
{ AID_MEDIA, "media.audio_flinger" },
{ AID_MEDIA, "media.player" },
{ AID_MEDIA, "media.camera" },
{ AID_MEDIA, "media.audio_policy" },
{ AID_MEDIA, "android.media.IAAHMetaDataService" },
{ 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" },
};
void *svcmgr_handle;
const char *str8(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(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(unsigned uid, uint16_t *name)
{
unsigned 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;
void *ptr;
struct binder_death death;
int allow_isolated;
unsigned len;
uint16_t name[0];
};
struct svcinfo *svclist = 0;
struct svcinfo *find_svc(uint16_t *s16, unsigned 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 0;
}
void svcinfo_death(struct binder_state *bs, void *ptr)
{
struct svcinfo *si = ptr;
ALOGI("service '%s' died\n", str8(si->name));
if (si->ptr) {
binder_release(bs, si->ptr);
si->ptr = 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'
};
void *do_find_service(struct binder_state *bs, uint16_t *s, unsigned len, unsigned uid)
{
struct svcinfo *si;
si = find_svc(s, len);
// ALOGI("check_service('%s') ptr = %p\n", str8(s), si ? si->ptr : 0);
if (si && si->ptr) {
if (!si->allow_isolated) {
// If this service doesn't allow access from isolated processes,
// then check the uid to see if it is isolated.
unsigned appid = uid % AID_USER;
if (appid >= AID_ISOLATED_START && appid <= AID_ISOLATED_END) {
return 0;
}
}
return si->ptr;
} else {
return 0;
}
}
int do_add_service(struct binder_state *bs,
uint16_t *s, unsigned len,
void *ptr, unsigned uid, int allow_isolated)
{
struct svcinfo *si;
//ALOGI("add_service('%s',%p,%s) uid=%d\n", str8(s), ptr,
// allow_isolated ? "allow_isolated" : "!allow_isolated", uid);
if (!ptr || (len == 0) || (len > 127))
return -1;
if (!svc_can_register(uid, s)) {
ALOGE("add_service('%s',%p) uid=%d - PERMISSION DENIED\n",
str8(s), ptr, uid);
return -1;
}
si = find_svc(s, len);
if (si) {
if (si->ptr) {
ALOGE("add_service('%s',%p) uid=%d - ALREADY REGISTERED, OVERRIDE\n",
str8(s), ptr, uid);
svcinfo_death(bs, si);
}
si->ptr = ptr;
} else {
si = malloc(sizeof(*si) + (len + 1) * sizeof(uint16_t));
if (!si) {
ALOGE("add_service('%s',%p) uid=%d - OUT OF MEMORY\n",
str8(s), ptr, uid);
return -1;
}
si->ptr = ptr;
si->len = len;
memcpy(si->name, s, (len + 1) * sizeof(uint16_t));
si->name[len] = '\0';
si->death.func = svcinfo_death;
si->death.ptr = si;
si->allow_isolated = allow_isolated;
si->next = svclist;
svclist = si;
}
binder_acquire(bs, ptr);
binder_link_to_death(bs, ptr, &si->death);
return 0;
}
int svcmgr_handler(struct binder_state *bs,
struct binder_txn *txn,
struct binder_io *msg,
struct binder_io *reply)
{
struct svcinfo *si;
uint16_t *s;
unsigned len;
void *ptr;
uint32_t strict_policy;
int allow_isolated;
// ALOGI("target=%p code=%d pid=%d uid=%d\n",
// txn->target, txn->code, txn->sender_pid, txn->sender_euid);
if (txn->target != svcmgr_handle)
return -1;
// 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);
ptr = do_find_service(bs, s, len, txn->sender_euid);
if (!ptr)
break;
bio_put_ref(reply, ptr);
return 0;
case SVC_MGR_ADD_SERVICE:
s = bio_get_string16(msg, &len);
ptr = bio_get_ref(msg);
allow_isolated = bio_get_uint32(msg) ? 1 : 0;
if (do_add_service(bs, s, len, ptr, txn->sender_euid, allow_isolated))
return -1;
break;
case SVC_MGR_LIST_SERVICES: {
unsigned 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;
void *svcmgr = BINDER_SERVICE_MANAGER;
bs = binder_open(128*1024);
if (binder_become_context_manager(bs)) {
ALOGE("cannot become context manager (%s)\n", strerror(errno));
return -1;
}
svcmgr_handle = svcmgr;
binder_loop(bs, svcmgr_handler);
return 0;
}
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