| /* |
| * 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 <sys/wait.h> |
| |
| #include "devices.h" |
| #include "util.h" |
| #include "log.h" |
| #include "list.h" |
| |
| #define SYSFS_PREFIX "/sys" |
| #define FIRMWARE_DIR "/etc/firmware" |
| |
| static int device_fd = -1; |
| |
| struct uevent { |
| const char *action; |
| const char *path; |
| const char *subsystem; |
| const char *firmware; |
| const char *partition_name; |
| int partition_num; |
| int major; |
| int minor; |
| }; |
| |
| static int open_uevent_socket(void) |
| { |
| struct sockaddr_nl addr; |
| int sz = 64*1024; // XXX larger? udev uses 16MB! |
| int on = 1; |
| 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)); |
| setsockopt(s, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)); |
| |
| 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; |
| }; |
| |
| struct perm_node { |
| struct perms_ dp; |
| struct listnode plist; |
| }; |
| static list_declare(dev_perms); |
| |
| /* |
| * Permission override when in emulator mode, must be parsed before |
| * system properties is initalized. |
| */ |
| int add_dev_perms(const char *name, mode_t perm, unsigned int uid, |
| unsigned int gid, unsigned short prefix) { |
| int size; |
| char *tmp = 0; |
| 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(&dev_perms, &node->plist); |
| return 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; |
| struct listnode *node; |
| struct perm_node *perm_node; |
| struct perms_ *dp; |
| |
| /* search the perms list in reverse so that ueventd.$hardware can |
| * override ueventd.rc |
| */ |
| list_for_each_reverse(node, &dev_perms) { |
| 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; |
| } |
| *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; |
| /* Temporarily change egid to avoid race condition setting the gid of the |
| * device node. Unforunately changing the euid would prevent creation of |
| * some device nodes, so the uid has to be set with chown() and is still |
| * racy. Fixing the gid race at least fixed the issue with system_server |
| * opening dynamic input devices under the AID_INPUT gid. */ |
| setegid(gid); |
| mknod(path, mode, dev); |
| chown(path, uid, -1); |
| setegid(AID_ROOT); |
| } |
| |
| #if 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; |
| uevent->partition_name = NULL; |
| uevent->partition_num = -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); |
| } else if(!strncmp(msg, "PARTN=", 6)) { |
| msg += 6; |
| uevent->partition_num = atoi(msg); |
| } else if(!strncmp(msg, "PARTNAME=", 9)) { |
| msg += 9; |
| uevent->partition_name = 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 char **parse_platform_block_device(struct uevent *uevent) |
| { |
| const char *driver; |
| const char *path; |
| char *slash; |
| int width; |
| char buf[256]; |
| char link_path[256]; |
| int fd; |
| int link_num = 0; |
| int ret; |
| char *p; |
| unsigned int size; |
| struct stat info; |
| |
| char **links = malloc(sizeof(char *) * 4); |
| if (!links) |
| return NULL; |
| memset(links, 0, sizeof(char *) * 4); |
| |
| /* Drop "/devices/platform/" */ |
| path = uevent->path; |
| driver = path + 18; |
| slash = strchr(driver, '/'); |
| if (!slash) |
| goto err; |
| width = slash - driver; |
| if (width <= 0) |
| goto err; |
| |
| snprintf(link_path, sizeof(link_path), "/dev/block/platform/%.*s", |
| width, driver); |
| |
| if (uevent->partition_name) { |
| p = strdup(uevent->partition_name); |
| sanitize(p); |
| if (asprintf(&links[link_num], "%s/by-name/%s", link_path, p) > 0) |
| link_num++; |
| else |
| links[link_num] = NULL; |
| free(p); |
| } |
| |
| if (uevent->partition_num >= 0) { |
| if (asprintf(&links[link_num], "%s/by-num/p%d", link_path, uevent->partition_num) > 0) |
| link_num++; |
| else |
| links[link_num] = NULL; |
| } |
| |
| slash = strrchr(path, '/'); |
| if (asprintf(&links[link_num], "%s/%s", link_path, slash + 1) > 0) |
| link_num++; |
| else |
| links[link_num] = NULL; |
| |
| return links; |
| |
| err: |
| free(links); |
| return NULL; |
| } |
| |
| static void handle_device_event(struct uevent *uevent) |
| { |
| char devpath[96]; |
| int devpath_ready = 0; |
| char *base, *name; |
| char **links = NULL; |
| int block; |
| int i; |
| |
| /* 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); |
| if (!strncmp(uevent->path, "/devices/platform/", 18)) |
| links = parse_platform_block_device(uevent); |
| } else { |
| block = 0; |
| /* this should probably be configurable somehow */ |
| if (!strncmp(uevent->subsystem, "usb", 3)) { |
| if (!strcmp(uevent->subsystem, "usb")) { |
| /* This imitates the file system that would be created |
| * if we were using devfs instead. |
| * Minors are broken up into groups of 128, starting at "001" |
| */ |
| int bus_id = uevent->minor / 128 + 1; |
| int device_id = uevent->minor % 128 + 1; |
| /* build directories */ |
| mkdir("/dev/bus", 0755); |
| mkdir("/dev/bus/usb", 0755); |
| snprintf(devpath, sizeof(devpath), "/dev/bus/usb/%03d", bus_id); |
| mkdir(devpath, 0755); |
| snprintf(devpath, sizeof(devpath), "/dev/bus/usb/%03d/%03d", bus_id, device_id); |
| devpath_ready = 1; |
| } else { |
| /* ignore other USB events */ |
| return; |
| } |
| } else 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, "sound", 5)) { |
| base = "/dev/snd/"; |
| 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/"; |
| } |
| |
| if (!devpath_ready) |
| snprintf(devpath, sizeof(devpath), "%s%s", base, name); |
| |
| if(!strcmp(uevent->action, "add")) { |
| make_device(devpath, block, uevent->major, uevent->minor); |
| if (links) { |
| for (i = 0; links[i]; i++) |
| make_link(devpath, links[i]); |
| } |
| } |
| |
| if(!strcmp(uevent->action, "remove")) { |
| if (links) { |
| for (i = 0; links[i]; i++) |
| remove_link(devpath, links[i]); |
| } |
| unlink(devpath); |
| } |
| |
| if (links) { |
| for (i = 0; links[i]; i++) |
| free(links[i]); |
| free(links); |
| } |
| } |
| |
| 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; |
| int status; |
| int ret; |
| |
| 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); |
| } else { |
| do { |
| ret = waitpid(pid, &status, 0); |
| } while (ret == -1 && errno == EINTR); |
| } |
| } |
| |
| #define UEVENT_MSG_LEN 1024 |
| void handle_device_fd() |
| { |
| for(;;) { |
| char msg[UEVENT_MSG_LEN+2]; |
| char cred_msg[CMSG_SPACE(sizeof(struct ucred))]; |
| struct iovec iov = {msg, sizeof(msg)}; |
| struct sockaddr_nl snl; |
| struct msghdr hdr = {&snl, sizeof(snl), &iov, 1, cred_msg, sizeof(cred_msg), 0}; |
| |
| ssize_t n = recvmsg(device_fd, &hdr, 0); |
| if (n <= 0) { |
| break; |
| } |
| |
| if ((snl.nl_groups != 1) || (snl.nl_pid != 0)) { |
| /* ignoring non-kernel netlink multicast message */ |
| continue; |
| } |
| |
| struct cmsghdr * cmsg = CMSG_FIRSTHDR(&hdr); |
| if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) { |
| /* no sender credentials received, ignore message */ |
| continue; |
| } |
| |
| struct ucred * cred = (struct ucred *)CMSG_DATA(cmsg); |
| if (cred->uid != 0) { |
| /* message from non-root user, ignore */ |
| continue; |
| } |
| |
| if(n >= UEVENT_MSG_LEN) /* overflow -- discard */ |
| continue; |
| |
| msg[n] = '\0'; |
| msg[n+1] = '\0'; |
| |
| struct uevent uevent; |
| 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(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(); |
| } |
| |
| 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(d2); |
| closedir(d2); |
| } |
| } |
| } |
| |
| static void coldboot(const char *path) |
| { |
| DIR *d = opendir(path); |
| if(d) { |
| do_coldboot(d); |
| closedir(d); |
| } |
| } |
| |
| void device_init(void) |
| { |
| suseconds_t t0, t1; |
| struct stat info; |
| int fd; |
| |
| device_fd = open_uevent_socket(); |
| if(device_fd < 0) |
| return; |
| |
| fcntl(device_fd, F_SETFD, FD_CLOEXEC); |
| fcntl(device_fd, F_SETFL, O_NONBLOCK); |
| |
| if (stat(coldboot_done, &info) < 0) { |
| t0 = get_usecs(); |
| coldboot("/sys/class"); |
| coldboot("/sys/block"); |
| coldboot("/sys/devices"); |
| t1 = get_usecs(); |
| fd = open(coldboot_done, O_WRONLY|O_CREAT, 0000); |
| close(fd); |
| log_event_print("coldboot %ld uS\n", ((long) (t1 - t0))); |
| } else { |
| log_event_print("skipping coldboot, already done\n"); |
| } |
| } |
| |
| int get_device_fd() |
| { |
| return device_fd; |
| } |