auto import from //depot/cupcake/@135843

1 files changed, 502 insertions, 0 deletions

diff --git a/init/property_service.c b/init/property_service.c
new file mode 100644
index 0000000..7a6416b
--- /dev/null
+++ b/init/property_service.c
@@ -0,0 +1,502 @@
+/*
+ * 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 <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <dirent.h>
+#include <limits.h>
+#include <errno.h>
+
+#include <cutils/misc.h>
+#include <cutils/sockets.h>
+#include <cutils/ashmem.h>
+
+#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
+#include <sys/_system_properties.h>
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/select.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <sys/mman.h>
+#include <sys/atomics.h>
+#include <private/android_filesystem_config.h>
+
+#include "property_service.h"
+#include "init.h"
+
+#define PERSISTENT_PROPERTY_DIR  "/data/property"
+
+static int persistent_properties_loaded = 0;
+
+/* White list of permissions for setting property services. */
+struct {
+    const char *prefix;
+    unsigned int uid;
+} property_perms[] = {
+    { "net.rmnet0.",    AID_RADIO },
+    { "net.gprs.",      AID_RADIO },
+    { "ril.",           AID_RADIO },
+    { "gsm.",           AID_RADIO },
+    { "net.dns",        AID_RADIO },
+    { "net.",           AID_SYSTEM },
+    { "dev.",           AID_SYSTEM },
+    { "runtime.",       AID_SYSTEM },
+    { "hw.",            AID_SYSTEM },
+    { "sys.",		AID_SYSTEM },
+    { "service.",	AID_SYSTEM },
+    { "wlan.",		AID_SYSTEM },
+    { "dhcp.",		AID_SYSTEM },
+    { "dhcp.",		AID_DHCP },
+    { "debug.",		AID_SHELL },
+    { "log.",		AID_SHELL },
+    { "persist.sys.",	AID_SYSTEM },
+    { "persist.service.",   AID_SYSTEM },
+    { NULL, 0 }
+};
+
+/*
+ * White list of UID that are allowed to start/stop services.
+ * Currently there are no user apps that require.
+ */
+struct {
+    const char *service;
+    unsigned int uid;
+} control_perms[] = {
+     {NULL, 0 }
+};
+
+typedef struct {
+    void *data;
+    size_t size;
+    int fd;
+} workspace;
+
+static int init_workspace(workspace *w, size_t size)
+{
+    void *data;
+    int fd;
+
+    fd = ashmem_create_region("system_properties", size);
+    if(fd < 0)
+        return -1;
+
+    data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+    if(data == MAP_FAILED)
+        goto out;
+
+    /* allow the wolves we share with to do nothing but read */
+    ashmem_set_prot_region(fd, PROT_READ);
+
+    w->data = data;
+    w->size = size;
+    w->fd = fd;
+
+    return 0;
+
+out:
+    close(fd);
+    return -1;
+}
+
+/* (8 header words + 247 toc words) = 1020 bytes */
+/* 1024 bytes header and toc + 247 prop_infos @ 128 bytes = 32640 bytes */
+
+#define PA_COUNT_MAX  247
+#define PA_INFO_START 1024
+#define PA_SIZE       32768
+
+static workspace pa_workspace;
+static prop_info *pa_info_array;
+
+extern prop_area *__system_property_area__;
+
+static int init_property_area(void)
+{
+    prop_area *pa;
+
+    if(pa_info_array)
+        return -1;
+
+    if(init_workspace(&pa_workspace, PA_SIZE))
+        return -1;
+
+    fcntl(pa_workspace.fd, F_SETFD, FD_CLOEXEC);
+
+    pa_info_array = (void*) (((char*) pa_workspace.data) + PA_INFO_START);
+
+    pa = pa_workspace.data;
+    memset(pa, 0, PA_SIZE);
+    pa->magic = PROP_AREA_MAGIC;
+    pa->version = PROP_AREA_VERSION;
+
+        /* plug into the lib property services */
+    __system_property_area__ = pa;
+
+    return 0;
+}
+
+static void update_prop_info(prop_info *pi, const char *value, unsigned len)
+{
+    pi->serial = pi->serial | 1;
+    memcpy(pi->value, value, len + 1);
+    pi->serial = (len << 24) | ((pi->serial + 1) & 0xffffff);
+    __futex_wake(&pi->serial, INT32_MAX);
+}
+
+static int property_write(prop_info *pi, const char *value)
+{
+    int valuelen = strlen(value);
+    if(valuelen >= PROP_VALUE_MAX) return -1;
+    update_prop_info(pi, value, valuelen);
+    return 0;
+}
+
+
+/*
+ * Checks permissions for starting/stoping system services.
+ * AID_SYSTEM and AID_ROOT are always allowed.
+ *
+ * Returns 1 if uid allowed, 0 otherwise.
+ */
+static int check_control_perms(const char *name, int uid) {
+    int i;
+    if (uid == AID_SYSTEM || uid == AID_ROOT)
+        return 1;
+
+    /* Search the ACL */
+    for (i = 0; control_perms[i].service; i++) {
+        if (strcmp(control_perms[i].service, name) == 0) {
+            if (control_perms[i].uid == uid)
+                return 1;
+        }
+    }
+    return 0;
+}
+
+/*
+ * Checks permissions for setting system properties.
+ * Returns 1 if uid allowed, 0 otherwise.
+ */
+static int check_perms(const char *name, unsigned int uid)
+{
+    int i;
+    if (uid == 0)
+        return 1;
+
+    if(!strncmp(name, "ro.", 3))
+        name +=3;
+
+    for (i = 0; property_perms[i].prefix; i++) {
+        int tmp;
+        if (strncmp(property_perms[i].prefix, name,
+                    strlen(property_perms[i].prefix)) == 0) {
+            if (property_perms[i].uid == uid) {
+                return 1;
+            }
+        }
+    }
+
+    return 0;
+}
+
+const char* property_get(const char *name)
+{
+    prop_info *pi;
+
+    if(strlen(name) >= PROP_NAME_MAX) return 0;
+
+    pi = (prop_info*) __system_property_find(name);
+
+    if(pi != 0) {
+        return pi->value;
+    } else {
+        return 0;
+    }
+}
+
+static void write_peristent_property(const char *name, const char *value)
+{
+    const char *tempPath = PERSISTENT_PROPERTY_DIR "/.temp";
+    char path[PATH_MAX];
+    int fd, length;
+
+    snprintf(path, sizeof(path), "%s/%s", PERSISTENT_PROPERTY_DIR, name);
+
+    fd = open(tempPath, O_WRONLY|O_CREAT|O_TRUNC, 0600);
+    if (fd < 0) {
+        ERROR("Unable to write persistent property to temp file %s errno: %d\n", tempPath, errno);
+        return;   
+    }
+    write(fd, value, strlen(value));
+    close(fd);
+
+    if (rename(tempPath, path)) {
+        unlink(tempPath);
+        ERROR("Unable to rename persistent property file %s to %s\n", tempPath, path);
+    }
+}
+
+int property_set(const char *name, const char *value)
+{
+    prop_area *pa;
+    prop_info *pi;
+
+    int namelen = strlen(name);
+    int valuelen = strlen(value);
+
+    if(namelen >= PROP_NAME_MAX) return -1;
+    if(valuelen >= PROP_VALUE_MAX) return -1;
+    if(namelen < 1) return -1;
+
+    pi = (prop_info*) __system_property_find(name);
+
+    if(pi != 0) {
+        /* ro.* properties may NEVER be modified once set */
+        if(!strncmp(name, "ro.", 3)) return -1;
+
+        pa = __system_property_area__;
+        update_prop_info(pi, value, valuelen);
+        pa->serial++;
+        __futex_wake(&pa->serial, INT32_MAX);
+    } else {
+        pa = __system_property_area__;
+        if(pa->count == PA_COUNT_MAX) return -1;
+
+        pi = pa_info_array + pa->count;
+        pi->serial = (valuelen << 24);
+        memcpy(pi->name, name, namelen + 1);
+        memcpy(pi->value, value, valuelen + 1);
+
+        pa->toc[pa->count] =
+            (namelen << 24) | (((unsigned) pi) - ((unsigned) pa));
+
+        pa->count++;
+        pa->serial++;
+        __futex_wake(&pa->serial, INT32_MAX);
+    }
+    /* If name starts with "net." treat as a DNS property. */
+    if (strncmp("net.", name, sizeof("net.") - 1) == 0)  {
+        if (strcmp("net.change", name) == 0) {
+            return 0;
+        }
+       /* 
+        * The 'net.change' property is a special property used track when any
+        * 'net.*' property name is updated. It is _ONLY_ updated here. Its value
+        * contains the last updated 'net.*' property.
+        */
+        property_set("net.change", name);
+    } else if (persistent_properties_loaded &&
+            strncmp("persist.", name, sizeof("persist.") - 1) == 0) {
+        /* 
+         * Don't write properties to disk until after we have read all default properties
+         * to prevent them from being overwritten by default values.
+         */
+        write_peristent_property(name, value);
+    }
+    property_changed(name, value);
+    return 0;
+}
+
+static int property_list(void (*propfn)(const char *key, const char *value, void *cookie),
+                  void *cookie)
+{
+    char name[PROP_NAME_MAX];
+    char value[PROP_VALUE_MAX];
+    const prop_info *pi;
+    unsigned n;
+
+    for(n = 0; (pi = __system_property_find_nth(n)); n++) {
+        __system_property_read(pi, name, value);
+        propfn(name, value, cookie);
+    }
+    return 0;
+}
+
+void handle_property_set_fd(int fd)
+{
+    prop_msg msg;
+    int s;
+    int r;
+    int res;
+    struct ucred cr;
+    struct sockaddr_un addr;
+    socklen_t addr_size = sizeof(addr);
+    socklen_t cr_size = sizeof(cr);
+
+    if ((s = accept(fd, (struct sockaddr *) &addr, &addr_size)) < 0) {
+        return;
+    }
+
+    /* Check socket options here */
+    if (getsockopt(s, SOL_SOCKET, SO_PEERCRED, &cr, &cr_size) < 0) {
+        close(s);
+        ERROR("Unable to recieve socket options\n");
+        return;
+    }
+
+    r = recv(s, &msg, sizeof(msg), 0);
+    close(s);
+    if(r != sizeof(prop_msg)) {
+        ERROR("sys_prop: mis-match msg size recieved: %d expected: %d\n",
+              r, sizeof(prop_msg));
+        return;
+    }
+
+    switch(msg.cmd) {
+    case PROP_MSG_SETPROP:
+        msg.name[PROP_NAME_MAX-1] = 0;
+        msg.value[PROP_VALUE_MAX-1] = 0;
+
+        if(memcmp(msg.name,"ctl.",4) == 0) {
+            if (check_control_perms(msg.value, cr.uid)) {
+                handle_control_message((char*) msg.name + 4, (char*) msg.value);
+            } else {
+                ERROR("sys_prop: Unable to %s service ctl [%s] uid: %d pid:%d\n",
+                        msg.name + 4, msg.value, cr.uid, cr.pid);
+            }
+        } else {
+            if (check_perms(msg.name, cr.uid)) {
+                property_set((char*) msg.name, (char*) msg.value);
+            } else {
+                ERROR("sys_prop: permission denied uid:%d  name:%s\n",
+                      cr.uid, msg.name);
+            }
+        }
+        break;
+
+    default:
+        break;
+    }
+}
+
+void get_property_workspace(int *fd, int *sz)
+{
+    *fd = pa_workspace.fd;
+    *sz = pa_workspace.size;
+}
+
+static void load_properties(char *data)
+{
+    char *key, *value, *eol, *sol, *tmp;
+
+    sol = data;
+    while((eol = strchr(sol, '\n'))) {
+        key = sol;
+        *eol++ = 0;
+        sol = eol;
+
+        value = strchr(key, '=');
+        if(value == 0) continue;
+        *value++ = 0;
+
+        while(isspace(*key)) key++;
+        if(*key == '#') continue;
+        tmp = value - 2;
+        while((tmp > key) && isspace(*tmp)) *tmp-- = 0;
+
+        while(isspace(*value)) value++;
+        tmp = eol - 2;
+        while((tmp > value) && isspace(*tmp)) *tmp-- = 0;
+
+        property_set(key, value);
+    }
+}
+
+static void load_properties_from_file(const char *fn)
+{
+    char *data;
+    unsigned sz;
+
+    data = read_file(fn, &sz);
+
+    if(data != 0) {
+        load_properties(data);
+        free(data);
+    }
+}
+
+static void load_persistent_properties()
+{
+    DIR* dir = opendir(PERSISTENT_PROPERTY_DIR);
+    struct dirent*  entry;
+    char path[PATH_MAX];
+    char value[PROP_VALUE_MAX];
+    int fd, length;
+
+    if (dir) {
+        while ((entry = readdir(dir)) != NULL) {
+            if (!strcmp(entry->d_name, ".") || !strcmp(entry->d_name, "..") ||
+                    strncmp("persist.", entry->d_name, sizeof("persist.") - 1))
+                continue;
+#if HAVE_DIRENT_D_TYPE
+            if (entry->d_type != DT_REG)
+                continue;
+#endif
+            /* open the file and read the property value */
+            snprintf(path, sizeof(path), "%s/%s", PERSISTENT_PROPERTY_DIR, entry->d_name);
+            fd = open(path, O_RDONLY);
+            if (fd >= 0) {
+                length = read(fd, value, sizeof(value) - 1);
+                if (length >= 0) {
+                    value[length] = 0;
+                    property_set(entry->d_name, value);
+                } else {
+                    ERROR("Unable to read persistent property file %s errno: %d\n", path, errno);
+                }
+                close(fd);
+            } else {
+                ERROR("Unable to open persistent property file %s errno: %d\n", path, errno);
+            }
+        }
+        closedir(dir);
+    } else {
+        ERROR("Unable to open persistent property directory %s errno: %d\n", PERSISTENT_PROPERTY_DIR, errno);
+    }
+    
+    persistent_properties_loaded = 1;
+}
+
+void property_init(void)
+{
+    init_property_area();
+    load_properties_from_file(PROP_PATH_RAMDISK_DEFAULT);
+}
+
+int start_property_service(void)
+{
+    int fd;
+
+    load_properties_from_file(PROP_PATH_SYSTEM_BUILD);
+    load_properties_from_file(PROP_PATH_SYSTEM_DEFAULT);
+    load_properties_from_file(PROP_PATH_LOCAL_OVERRIDE);
+    /* Read persistent properties after all default values have been loaded. */
+    load_persistent_properties();
+
+    fd = create_socket(PROP_SERVICE_NAME, SOCK_STREAM, 0666, 0, 0);
+    if(fd < 0) return -1;
+    fcntl(fd, F_SETFD, FD_CLOEXEC);
+    fcntl(fd, F_SETFL, O_NONBLOCK);
+
+    listen(fd, 8);
+    return fd;
+}