/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <dirent.h>
#include <unistd.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <linux/netlink.h>
#include <private/android_filesystem_config.h>
#include <sys/time.h>
#include <asm/page.h>
#include "init.h"
#include "devices.h"
#define CMDLINE_PREFIX "/dev"
#define SYSFS_PREFIX "/sys"
#define FIRMWARE_DIR "/etc/firmware"
#define MAX_QEMU_PERM 6
struct uevent {
const char *action;
const char *path;
const char *subsystem;
const char *firmware;
int major;
int minor;
};
static int open_uevent_socket(void)
{
struct sockaddr_nl addr;
int sz = 64*1024; // XXX larger? udev uses 16MB!
int s;
memset(&addr, 0, sizeof(addr));
addr.nl_family = AF_NETLINK;
addr.nl_pid = getpid();
addr.nl_groups = 0xffffffff;
s = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
if(s < 0)
return -1;
setsockopt(s, SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz));
if(bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
close(s);
return -1;
}
return s;
}
struct perms_ {
char *name;
mode_t perm;
unsigned int uid;
unsigned int gid;
unsigned short prefix;
};
static struct perms_ devperms[] = {
{ "/dev/null", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/zero", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/full", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/ptmx", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/tty", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/random", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/urandom", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/ashmem", 0666, AID_ROOT, AID_ROOT, 0 },
{ "/dev/binder", 0666, AID_ROOT, AID_ROOT, 0 },
/* logger should be world writable (for logging) but not readable */
{ "/dev/log/", 0662, AID_ROOT, AID_LOG, 1 },
/* these should not be world writable */
{ "/dev/android_adb", 0660, AID_ADB, AID_ADB, 0 },
{ "/dev/android_adb_enable", 0660, AID_ADB, AID_ADB, 0 },
{ "/dev/ttyMSM0", 0600, AID_BLUETOOTH, AID_BLUETOOTH, 0 },
{ "/dev/ttyHS0", 0600, AID_BLUETOOTH, AID_BLUETOOTH, 0 },
{ "/dev/uinput", 0600, AID_BLUETOOTH, AID_BLUETOOTH, 0 },
{ "/dev/alarm", 0664, AID_SYSTEM, AID_RADIO, 0 },
{ "/dev/tty0", 0660, AID_ROOT, AID_SYSTEM, 0 },
{ "/dev/graphics/", 0660, AID_ROOT, AID_GRAPHICS, 1 },
{ "/dev/hw3d", 0660, AID_SYSTEM, AID_GRAPHICS, 0 },
{ "/dev/input/", 0660, AID_ROOT, AID_INPUT, 1 },
{ "/dev/eac", 0660, AID_ROOT, AID_AUDIO, 0 },
{ "/dev/cam", 0660, AID_ROOT, AID_CAMERA, 0 },
{ "/dev/pmem", 0660, AID_SYSTEM, AID_GRAPHICS, 0 },
{ "/dev/pmem_gpu", 0660, AID_SYSTEM, AID_GRAPHICS, 1 },
{ "/dev/pmem_adsp", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/pmem_camera", 0660, AID_SYSTEM, AID_CAMERA, 1 },
{ "/dev/oncrpc/", 0660, AID_ROOT, AID_SYSTEM, 1 },
{ "/dev/adsp/", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/mt9t013", 0660, AID_SYSTEM, AID_SYSTEM, 0 },
{ "/dev/msm_camera/", 0660, AID_SYSTEM, AID_SYSTEM, 1 },
{ "/dev/akm8976_daemon",0640, AID_COMPASS, AID_SYSTEM, 0 },
{ "/dev/akm8976_aot", 0640, AID_COMPASS, AID_SYSTEM, 0 },
{ "/dev/akm8976_pffd", 0640, AID_COMPASS, AID_SYSTEM, 0 },
{ "/dev/msm_pcm_out", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/msm_pcm_in", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/msm_pcm_ctl", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/msm_snd", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/msm_mp3", 0660, AID_SYSTEM, AID_AUDIO, 1 },
{ "/dev/msm_audpre", 0660, AID_SYSTEM, AID_AUDIO, 0 },
{ "/dev/htc-acoustic", 0660, AID_SYSTEM, AID_AUDIO, 0 },
{ "/dev/smd0", 0640, AID_RADIO, AID_RADIO, 0 },
{ "/dev/qemu_trace", 0666, AID_SYSTEM, AID_SYSTEM, 0 },
{ "/dev/qmi", 0640, AID_RADIO, AID_RADIO, 0 },
{ "/dev/qmi0", 0640, AID_RADIO, AID_RADIO, 0 },
{ "/dev/qmi1", 0640, AID_RADIO, AID_RADIO, 0 },
{ "/dev/qmi2", 0640, AID_RADIO, AID_RADIO, 0 },
{ "/dev/ppp", 0660, AID_RADIO, AID_VPN, 0 },
{ "/dev/tun", 0640, AID_VPN, AID_VPN, 0 },
{ NULL, 0, 0, 0, 0 },
};
/* devperms_partners list and perm_node are for hardware specific /dev entries */
struct perm_node {
struct perms_ dp;
struct listnode plist;
};
list_declare(devperms_partners);
/*
* Permission override when in emulator mode, must be parsed before
* system properties is initalized.
*/
static int qemu_perm_count;
static struct perms_ qemu_perms[MAX_QEMU_PERM + 1];
int add_devperms_partners(const char *name, mode_t perm, unsigned int uid,
unsigned int gid, unsigned short prefix) {
int size;
struct perm_node *node = malloc(sizeof (struct perm_node));
if (!node)
return -ENOMEM;
size = strlen(name) + 1;
if ((node->dp.name = malloc(size)) == NULL)
return -ENOMEM;
memcpy(node->dp.name, name, size);
node->dp.perm = perm;
node->dp.uid = uid;
node->dp.gid = gid;
node->dp.prefix = prefix;
list_add_tail(&devperms_partners, &node->plist);
return 0;
}
void qemu_init(void) {
qemu_perm_count = 0;
memset(&qemu_perms, 0, sizeof(qemu_perms));
}
static int qemu_perm(const char* name, mode_t perm, unsigned int uid,
unsigned int gid, unsigned short prefix)
{
char *buf;
if (qemu_perm_count == MAX_QEMU_PERM)
return -ENOSPC;
buf = malloc(strlen(name) + 1);
if (!buf)
return -errno;
strlcpy(buf, name, strlen(name) + 1);
qemu_perms[qemu_perm_count].name = buf;
qemu_perms[qemu_perm_count].perm = perm;
qemu_perms[qemu_perm_count].uid = uid;
qemu_perms[qemu_perm_count].gid = gid;
qemu_perms[qemu_perm_count].prefix = prefix;
qemu_perm_count++;
return 0;
}
/* Permission overrides for emulator that are parsed from /proc/cmdline. */
void qemu_cmdline(const char* name, const char *value)
{
char *buf;
if (!strcmp(name, "android.ril")) {
/* cmd line params currently assume /dev/ prefix */
if (asprintf(&buf, CMDLINE_PREFIX"/%s", value) == -1) {
return;
}
INFO("nani- buf:: %s\n", buf);
qemu_perm(buf, 0660, AID_RADIO, AID_ROOT, 0);
}
}
static int get_device_perm_inner(struct perms_ *perms, const char *path,
unsigned *uid, unsigned *gid, mode_t *perm)
{
int i;
for(i = 0; perms[i].name; i++) {
if(perms[i].prefix) {
if(strncmp(path, perms[i].name, strlen(perms[i].name)))
continue;
} else {
if(strcmp(path, perms[i].name))
continue;
}
*uid = perms[i].uid;
*gid = perms[i].gid;
*perm = perms[i].perm;
return 0;
}
return -1;
}
/* First checks for emulator specific permissions specified in /proc/cmdline. */
static mode_t get_device_perm(const char *path, unsigned *uid, unsigned *gid)
{
mode_t perm;
if (get_device_perm_inner(qemu_perms, path, uid, gid, &perm) == 0) {
return perm;
} else if (get_device_perm_inner(devperms, path, uid, gid, &perm) == 0) {
return perm;
} else {
struct listnode *node;
struct perm_node *perm_node;
struct perms_ *dp;
/* Check partners list. */
list_for_each(node, &devperms_partners) {
perm_node = node_to_item(node, struct perm_node, plist);
dp = &perm_node->dp;
if (dp->prefix) {
if (strncmp(path, dp->name, strlen(dp->name)))
continue;
} else {
if (strcmp(path, dp->name))
continue;
}
/* Found perm in partner list. */
*uid = dp->uid;
*gid = dp->gid;
return dp->perm;
}
/* Default if nothing found. */
*uid = 0;
*gid = 0;
return 0600;
}
}
static void make_device(const char *path, int block, int major, int minor)
{
unsigned uid;
unsigned gid;
mode_t mode;
dev_t dev;
if(major > 255 || minor > 255)
return;
mode = get_device_perm(path, &uid, &gid) | (block ? S_IFBLK : S_IFCHR);
dev = (major << 8) | minor;
mknod(path, mode, dev);
chown(path, uid, gid);
}
#ifdef LOG_UEVENTS
static inline suseconds_t get_usecs(void)
{
struct timeval tv;
gettimeofday(&tv, 0);
return tv.tv_sec * (suseconds_t) 1000000 + tv.tv_usec;
}
#define log_event_print(x...) INFO(x)
#else
#define log_event_print(fmt, args...) do { } while (0)
#define get_usecs() 0
#endif
static void parse_event(const char *msg, struct uevent *uevent)
{
uevent->action = "";
uevent->path = "";
uevent->subsystem = "";
uevent->firmware = "";
uevent->major = -1;
uevent->minor = -1;
/* currently ignoring SEQNUM */
while(*msg) {
if(!strncmp(msg, "ACTION=", 7)) {
msg += 7;
uevent->action = msg;
} else if(!strncmp(msg, "DEVPATH=", 8)) {
msg += 8;
uevent->path = msg;
} else if(!strncmp(msg, "SUBSYSTEM=", 10)) {
msg += 10;
uevent->subsystem = msg;
} else if(!strncmp(msg, "FIRMWARE=", 9)) {
msg += 9;
uevent->firmware = msg;
} else if(!strncmp(msg, "MAJOR=", 6)) {
msg += 6;
uevent->major = atoi(msg);
} else if(!strncmp(msg, "MINOR=", 6)) {
msg += 6;
uevent->minor = atoi(msg);
}
/* advance to after the next \0 */
while(*msg++)
;
}
log_event_print("event { '%s', '%s', '%s', '%s', %d, %d }\n",
uevent->action, uevent->path, uevent->subsystem,
uevent->firmware, uevent->major, uevent->minor);
}
static void handle_device_event(struct uevent *uevent)
{
char devpath[96];
char *base, *name;
int block;
/* if it's not a /dev device, nothing to do */
if((uevent->major < 0) || (uevent->minor < 0))
return;
/* do we have a name? */
name = strrchr(uevent->path, '/');
if(!name)
return;
name++;
/* too-long names would overrun our buffer */
if(strlen(name) > 64)
return;
/* are we block or char? where should we live? */
if(!strncmp(uevent->subsystem, "block", 5)) {
block = 1;
base = "/dev/block/";
mkdir(base, 0755);
} else {
block = 0;
/* this should probably be configurable somehow */
if(!strncmp(uevent->subsystem, "graphics", 8)) {
base = "/dev/graphics/";
mkdir(base, 0755);
} else if (!strncmp(uevent->subsystem, "oncrpc", 6)) {
base = "/dev/oncrpc/";
mkdir(base, 0755);
} else if (!strncmp(uevent->subsystem, "adsp", 4)) {
base = "/dev/adsp/";
mkdir(base, 0755);
} else if (!strncmp(uevent->subsystem, "msm_camera", 10)) {
base = "/dev/msm_camera/";
mkdir(base, 0755);
} else if(!strncmp(uevent->subsystem, "input", 5)) {
base = "/dev/input/";
mkdir(base, 0755);
} else if(!strncmp(uevent->subsystem, "mtd", 3)) {
base = "/dev/mtd/";
mkdir(base, 0755);
} else if(!strncmp(uevent->subsystem, "misc", 4) &&
!strncmp(name, "log_", 4)) {
base = "/dev/log/";
mkdir(base, 0755);
name += 4;
} else
base = "/dev/";
}
snprintf(devpath, sizeof(devpath), "%s%s", base, name);
if(!strcmp(uevent->action, "add")) {
make_device(devpath, block, uevent->major, uevent->minor);
return;
}
if(!strcmp(uevent->action, "remove")) {
unlink(devpath);
return;
}
}
static int load_firmware(int fw_fd, int loading_fd, int data_fd)
{
struct stat st;
long len_to_copy;
int ret = 0;
if(fstat(fw_fd, &st) < 0)
return -1;
len_to_copy = st.st_size;
write(loading_fd, "1", 1); /* start transfer */
while (len_to_copy > 0) {
char buf[PAGE_SIZE];
ssize_t nr;
nr = read(fw_fd, buf, sizeof(buf));
if(!nr)
break;
if(nr < 0) {
ret = -1;
break;
}
len_to_copy -= nr;
while (nr > 0) {
ssize_t nw = 0;
nw = write(data_fd, buf + nw, nr);
if(nw <= 0) {
ret = -1;
goto out;
}
nr -= nw;
}
}
out:
if(!ret)
write(loading_fd, "0", 1); /* successful end of transfer */
else
write(loading_fd, "-1", 2); /* abort transfer */
return ret;
}
static void process_firmware_event(struct uevent *uevent)
{
char *root, *loading, *data, *file;
int l, loading_fd, data_fd, fw_fd;
log_event_print("firmware event { '%s', '%s' }\n",
uevent->path, uevent->firmware);
l = asprintf(&root, SYSFS_PREFIX"%s/", uevent->path);
if (l == -1)
return;
l = asprintf(&loading, "%sloading", root);
if (l == -1)
goto root_free_out;
l = asprintf(&data, "%sdata", root);
if (l == -1)
goto loading_free_out;
l = asprintf(&file, FIRMWARE_DIR"/%s", uevent->firmware);
if (l == -1)
goto data_free_out;
loading_fd = open(loading, O_WRONLY);
if(loading_fd < 0)
goto file_free_out;
data_fd = open(data, O_WRONLY);
if(data_fd < 0)
goto loading_close_out;
fw_fd = open(file, O_RDONLY);
if(fw_fd < 0)
goto data_close_out;
if(!load_firmware(fw_fd, loading_fd, data_fd))
log_event_print("firmware copy success { '%s', '%s' }\n", root, file);
else
log_event_print("firmware copy failure { '%s', '%s' }\n", root, file);
close(fw_fd);
data_close_out:
close(data_fd);
loading_close_out:
close(loading_fd);
file_free_out:
free(file);
data_free_out:
free(data);
loading_free_out:
free(loading);
root_free_out:
free(root);
}
static void handle_firmware_event(struct uevent *uevent)
{
pid_t pid;
if(strcmp(uevent->subsystem, "firmware"))
return;
if(strcmp(uevent->action, "add"))
return;
/* we fork, to avoid making large memory allocations in init proper */
pid = fork();
if (!pid) {
process_firmware_event(uevent);
exit(EXIT_SUCCESS);
}
}
#define UEVENT_MSG_LEN 1024
void handle_device_fd(int fd)
{
char msg[UEVENT_MSG_LEN+2];
int n;
while((n = recv(fd, msg, UEVENT_MSG_LEN, 0)) > 0) {
struct uevent uevent;
if(n == UEVENT_MSG_LEN) /* overflow -- discard */
continue;
msg[n] = '\0';
msg[n+1] = '\0';
parse_event(msg, &uevent);
handle_device_event(&uevent);
handle_firmware_event(&uevent);
}
}
/* Coldboot walks parts of the /sys tree and pokes the uevent files
** to cause the kernel to regenerate device add events that happened
** before init's device manager was started
**
** We drain any pending events from the netlink socket every time
** we poke another uevent file to make sure we don't overrun the
** socket's buffer.
*/
static void do_coldboot(int event_fd, DIR *d)
{
struct dirent *de;
int dfd, fd;
dfd = dirfd(d);
fd = openat(dfd, "uevent", O_WRONLY);
if(fd >= 0) {
write(fd, "add\n", 4);
close(fd);
handle_device_fd(event_fd);
}
while((de = readdir(d))) {
DIR *d2;
if(de->d_type != DT_DIR || de->d_name[0] == '.')
continue;
fd = openat(dfd, de->d_name, O_RDONLY | O_DIRECTORY);
if(fd < 0)
continue;
d2 = fdopendir(fd);
if(d2 == 0)
close(fd);
else {
do_coldboot(event_fd, d2);
closedir(d2);
}
}
}
static void coldboot(int event_fd, const char *path)
{
DIR *d = opendir(path);
if(d) {
do_coldboot(event_fd, d);
closedir(d);
}
}
int device_init(void)
{
suseconds_t t0, t1;
int fd;
fd = open_uevent_socket();
if(fd < 0)
return -1;
fcntl(fd, F_SETFD, FD_CLOEXEC);
fcntl(fd, F_SETFL, O_NONBLOCK);
t0 = get_usecs();
coldboot(fd, "/sys/class");
coldboot(fd, "/sys/block");
coldboot(fd, "/sys/devices");
t1 = get_usecs();
log_event_print("coldboot %ld uS\n", ((long) (t1 - t0)));
return fd;
}