ubusd_proto.c

   1 #include <arpa/inet.h>
   2 #include "ubusd.h"
   3
   4 struct blob_buf b;
   5 static struct ubus_msg_buf *retmsg;
   6 static int *retmsg_data;
   7
   8 static struct blob_attr *attrbuf[UBUS_ATTR_MAX];
   9
  10 typedef int (*ubus_cmd_cb)(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr);
  11
  12 static const struct blob_attr_info ubus_policy[UBUS_ATTR_MAX] = {
  13         [UBUS_ATTR_SIGNATURE] = { .type = BLOB_ATTR_NESTED },
  14         [UBUS_ATTR_OBJTYPE] = { .type = BLOB_ATTR_INT32 },
  15         [UBUS_ATTR_OBJPATH] = { .type = BLOB_ATTR_STRING },
  16         [UBUS_ATTR_OBJID] = { .type = BLOB_ATTR_INT32 },
  17         [UBUS_ATTR_STATUS] = { .type = BLOB_ATTR_INT32 },
  18 };
  19
  20 static struct blob_attr **ubus_parse_msg(struct blob_attr *msg)
  21 {
  22         blob_parse(msg, attrbuf, ubus_policy, UBUS_ATTR_MAX);
  23         return attrbuf;
  24 }
  25
  26 static void ubus_msg_init(struct ubus_msg_buf *ub, uint8_t type, uint16_t seq, uint32_t peer)
  27 {
  28         ub->hdr.version = 0;
  29         ub->hdr.type = type;
  30         ub->hdr.seq = seq;
  31         ub->hdr.peer = peer;
  32 }
  33
  34 static struct ubus_msg_buf *ubus_msg_from_blob(bool shared)
  35 {
  36         return ubus_msg_new(b.head, blob_raw_len(b.head), shared);
  37 }
  38
  39 static struct ubus_msg_buf *ubus_reply_from_blob(struct ubus_msg_buf *ub, bool shared)
  40 {
  41         struct ubus_msg_buf *new;
  42
  43         new = ubus_msg_new(b.head, blob_raw_len(b.head), shared);
  44         if (!new)
  45                 return NULL;
  46
  47         ubus_msg_init(new, UBUS_MSG_DATA, ub->hdr.seq, ub->hdr.peer);
  48         return new;
  49 }
  50
  51 bool ubusd_send_hello(struct ubus_client *cl)
  52 {
  53         struct ubus_msg_buf *ub;
  54
  55         blob_buf_init(&b, 0);
  56         ub = ubus_msg_from_blob(true);
  57         if (!ub)
  58                 return false;
  59
  60         ubus_msg_init(ub, UBUS_MSG_HELLO, 0, cl->id.id);
  61         ubus_msg_send(cl, ub, true);
  62         return true;
  63 }
  64
  65 static int ubusd_send_pong(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
  66 {
  67         ub->hdr.type = UBUS_MSG_DATA;
  68         ubus_msg_send(cl, ub, false);
  69         return 0;
  70 }
  71
  72 static int ubusd_handle_remove_object(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
  73 {
  74         struct ubus_object *obj;
  75
  76         if (!attr[UBUS_ATTR_OBJID])
  77                 return UBUS_STATUS_INVALID_ARGUMENT;
  78
  79         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
  80         if (!obj)
  81                 return UBUS_STATUS_NOT_FOUND;
  82
  83         if (obj->client != cl)
  84                 return UBUS_STATUS_PERMISSION_DENIED;
  85
  86         blob_buf_init(&b, 0);
  87         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
  88
  89         /* check if we're removing the object type as well */
  90         if (obj->type && obj->type->refcount == 1)
  91                 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
  92
  93         ubusd_free_object(obj);
  94
  95         ub = ubus_reply_from_blob(ub, true);
  96         if (!ub)
  97                 return UBUS_STATUS_NO_DATA;
  98
  99         ubus_msg_send(cl, ub, true);
 100         return 0;
 101 }
 102
 103 static int ubusd_handle_add_object(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 104 {
 105         struct ubus_object *obj;
 106
 107         obj = ubusd_create_object(cl, attr);
 108         if (!obj)
 109                 return UBUS_STATUS_INVALID_ARGUMENT;
 110
 111         blob_buf_init(&b, 0);
 112         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 113         if (attr[UBUS_ATTR_SIGNATURE])
 114                 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 115
 116         ub = ubus_reply_from_blob(ub, true);
 117         if (!ub)
 118                 return UBUS_STATUS_NO_DATA;
 119
 120         ubus_msg_send(cl, ub, true);
 121         return 0;
 122 }
 123
 124 static void ubusd_send_obj(struct ubus_client *cl, struct ubus_msg_buf *ub, struct ubus_object *obj)
 125 {
 126         struct ubus_method *m;
 127         void *s;
 128
 129         blob_buf_init(&b, 0);
 130
 131         if (obj->path.key)
 132                 blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->path.key);
 133         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 134         blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 135
 136         s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
 137         list_for_each_entry(m, &obj->type->methods, list)
 138                 blob_put(&b, blob_id(m->data), blob_data(m->data), blob_len(m->data));
 139         blob_nest_end(&b, s);
 140
 141         ub = ubus_reply_from_blob(ub, true);
 142         if (!ub)
 143                 return;
 144
 145         ubus_msg_send(cl, ub, true);
 146 }
 147
 148 static int ubusd_handle_lookup(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 149 {
 150         struct ubus_object *obj;
 151         char *objpath;
 152         bool wildcard = false;
 153         bool found = false;
 154         int len;
 155
 156         if (!attr[UBUS_ATTR_OBJPATH]) {
 157                 avl_for_each_element(&path, obj, path)
 158                         ubusd_send_obj(cl, ub, obj);
 159                 return 0;
 160         }
 161
 162         objpath = blob_data(attr[UBUS_ATTR_OBJPATH]);
 163         len = strlen(objpath);
 164         if (objpath[len - 1] != '*') {
 165                 obj = avl_find_element(&path, objpath, obj, path);
 166                 if (!obj)
 167                         return UBUS_STATUS_NOT_FOUND;
 168
 169                 ubusd_send_obj(cl, ub, obj);
 170                 return 0;
 171         }
 172
 173         objpath[--len] = 0;
 174         wildcard = true;
 175
 176         obj = avl_find_ge_element(&path, objpath, obj, path);
 177         if (!obj)
 178                 return UBUS_STATUS_NOT_FOUND;
 179
 180         while (!strncmp(objpath, obj->path.key, len)) {
 181                 found = true;
 182                 ubusd_send_obj(cl, ub, obj);
 183                 if (obj == avl_last_element(&path, obj, path))
 184                         break;
 185                 obj = avl_next_element(obj, path);
 186         }
 187
 188         if (!found)
 189                 return UBUS_STATUS_NOT_FOUND;
 190
 191         return 0;
 192 }
 193
 194 static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 195 {
 196         struct ubus_object *obj = NULL;
 197         struct ubus_id *id;
 198         const char *method;
 199
 200         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 201                 return UBUS_STATUS_INVALID_ARGUMENT;
 202
 203         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 204         if (!id)
 205                 return UBUS_STATUS_NOT_FOUND;
 206
 207         obj = container_of(id, struct ubus_object, id);
 208
 209         method = blob_data(attr[UBUS_ATTR_METHOD]);
 210
 211         if (!obj->client)
 212                 return obj->recv_msg(cl, method, attr[UBUS_ATTR_DATA]);
 213
 214         blob_buf_init(&b, 0);
 215         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 216         blob_put_string(&b, UBUS_ATTR_METHOD, method);
 217         if (attr[UBUS_ATTR_DATA])
 218                 blob_put(&b, UBUS_ATTR_DATA, blob_data(attr[UBUS_ATTR_DATA]),
 219                          blob_len(attr[UBUS_ATTR_DATA]));
 220
 221         ubus_msg_free(ub);
 222
 223         ub = ubus_reply_from_blob(ub, true);
 224         if (!ub)
 225                 return UBUS_STATUS_NO_DATA;
 226
 227         ub->hdr.type = UBUS_MSG_INVOKE;
 228         ub->hdr.peer = cl->id.id;
 229         ubus_msg_send(obj->client, ub, true);
 230
 231         return -1;
 232 }
 233
 234 static struct ubus_client *ubusd_get_client_by_id(uint32_t id)
 235 {
 236         struct ubus_id *clid;
 237
 238         clid = ubus_find_id(&clients, id);
 239         if (!clid)
 240                 return NULL;
 241
 242         return container_of(clid, struct ubus_client, id);
 243 }
 244
 245 static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 246 {
 247         struct ubus_object *obj;
 248
 249         if (!attr[UBUS_ATTR_OBJID] ||
 250             (ub->hdr.type == UBUS_MSG_STATUS && !attr[UBUS_ATTR_STATUS]) ||
 251             (ub->hdr.type == UBUS_MSG_DATA && !attr[UBUS_ATTR_DATA]))
 252                 goto error;
 253
 254         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 255         if (!obj)
 256                 goto error;
 257
 258         if (cl != obj->client)
 259                 goto error;
 260
 261         cl = ubusd_get_client_by_id(ub->hdr.peer);
 262         if (!cl)
 263                 goto error;
 264
 265         ub->hdr.peer = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 266         ubus_msg_send(cl, ub, true);
 267         return -1;
 268
 269 error:
 270         ubus_msg_free(ub);
 271         return -1;
 272 }
 273
 274 static const ubus_cmd_cb handlers[__UBUS_MSG_LAST] = {
 275         [UBUS_MSG_PING] = ubusd_send_pong,
 276         [UBUS_MSG_ADD_OBJECT] = ubusd_handle_add_object,
 277         [UBUS_MSG_REMOVE_OBJECT] = ubusd_handle_remove_object,
 278         [UBUS_MSG_LOOKUP] = ubusd_handle_lookup,
 279         [UBUS_MSG_INVOKE] = ubusd_handle_invoke,
 280         [UBUS_MSG_STATUS] = ubusd_handle_response,
 281         [UBUS_MSG_DATA] = ubusd_handle_response,
 282 };
 283
 284 void ubusd_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub)
 285 {
 286         ubus_cmd_cb cb = NULL;
 287         int ret;
 288
 289         retmsg->hdr.seq = ub->hdr.seq;
 290         retmsg->hdr.peer = ub->hdr.peer;
 291
 292         if (ub->hdr.type < __UBUS_MSG_LAST)
 293                 cb = handlers[ub->hdr.type];
 294
 295         if (cb)
 296                 ret = cb(cl, ub, ubus_parse_msg(ub->data));
 297         else
 298                 ret = UBUS_STATUS_INVALID_COMMAND;
 299
 300         if (ret == -1)
 301                 return;
 302
 303         ubus_msg_free(ub);
 304
 305         *retmsg_data = htonl(ret);
 306         ubus_msg_send(cl, retmsg, false);
 307 }
 308
 309 static void __init ubusd_proto_init(void)
 310 {
 311         blob_buf_init(&b, 0);
 312         blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 313
 314         retmsg = ubus_msg_from_blob(false);
 315         if (!retmsg)
 316                 exit(1);
 317
 318         retmsg->hdr.type = UBUS_MSG_STATUS;
 319         retmsg_data = blob_data(blob_data(retmsg->data));
 320 }