proto-shell.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <glob.h>
   5 #include <unistd.h>
   6 #include <fcntl.h>
   7
   8 #include <libubox/blobmsg_json.h>
   9
  10 #include "netifd.h"
  11 #include "interface.h"
  12 #include "interface-ip.h"
  13 #include "proto.h"
  14
  15 static LIST_HEAD(handlers);
  16 static int proto_fd;
  17
  18 struct proto_shell_handler {
  19         struct list_head list;
  20         struct proto_handler proto;
  21         struct config_param_list config;
  22         char *config_buf;
  23         char script_name[];
  24 };
  25
  26 struct proto_shell_state {
  27         struct interface_proto_state proto;
  28         struct proto_shell_handler *handler;
  29         struct blob_attr *config;
  30 };
  31
  32 #define DUMP_SUFFIX     " '' dump"
  33
  34 static int run_script(const char **argv)
  35 {
  36         int pid, ret;
  37
  38         if ((pid = fork()) < 0)
  39                 return -1;
  40
  41         if (!pid) {
  42                 fchdir(proto_fd);
  43                 execvp(argv[0], (char **) argv);
  44                 exit(127);
  45         }
  46
  47         if (waitpid(pid, &ret, 0) == -1)
  48                 ret = -1;
  49
  50         if (ret > 0)
  51                 return -ret;
  52
  53         return 0;
  54 }
  55
  56 static int
  57 proto_shell_handler(struct interface_proto_state *proto,
  58                     enum interface_proto_cmd cmd, bool force)
  59 {
  60         struct proto_shell_state *state;
  61         struct proto_shell_handler *handler;
  62         const char *argv[5];
  63         char *config;
  64         int ret;
  65
  66         state = container_of(proto, struct proto_shell_state, proto);
  67         handler = state->handler;
  68
  69         config = blobmsg_format_json(state->config, true);
  70         if (!config)
  71                 return -1;
  72
  73         argv[0] = handler->script_name;
  74         argv[1] = handler->proto.name;
  75         argv[2] = "teardown";
  76         argv[3] = config;
  77         argv[4] = NULL;
  78
  79         switch(cmd) {
  80         case PROTO_CMD_SETUP:
  81                 argv[2] = "setup";
  82                 /* fall through */
  83         case PROTO_CMD_TEARDOWN:
  84                 ret = run_script(argv);
  85                 break;
  86         }
  87
  88         free(config);
  89
  90         return ret;
  91 }
  92
  93 static void
  94 proto_shell_free(struct interface_proto_state *proto)
  95 {
  96         struct proto_shell_state *state;
  97
  98         state = container_of(proto, struct proto_shell_state, proto);
  99         free(state->config);
 100         free(state);
 101 }
 102
 103 struct interface_proto_state *
 104 proto_shell_attach(const struct proto_handler *h, struct interface *iface,
 105                    struct blob_attr *attr)
 106 {
 107         struct proto_shell_state *state;
 108
 109         state = calloc(1, sizeof(*state));
 110         state->config = malloc(blob_pad_len(attr));
 111         if (!state->config)
 112                 goto error;
 113
 114         memcpy(state->config, attr, blob_pad_len(attr));
 115         state->proto.free = proto_shell_free;
 116         state->proto.handler = proto_shell_handler;
 117         state->handler = container_of(h, struct proto_shell_handler, proto);
 118
 119         return &state->proto;
 120
 121 error:
 122         free(state);
 123         return NULL;
 124 }
 125
 126 static char *
 127 proto_shell_parse_config(struct config_param_list *config, struct json_object *obj)
 128 {
 129         struct blobmsg_policy *attrs;
 130         char *str_buf, *str_cur;
 131         int str_len = 0;
 132         int i;
 133
 134         attrs = calloc(1, sizeof(*attrs));
 135         if (!attrs)
 136                 return NULL;
 137
 138         config->n_params = json_object_array_length(obj);
 139         config->params = attrs;
 140         for (i = 0; i < config->n_params; i++) {
 141                 struct json_object *cur, *name, *type;
 142
 143                 cur = json_object_array_get_idx(obj, i);
 144                 if (!cur || json_object_get_type(cur) != json_type_array)
 145                         goto error;
 146
 147                 name = json_object_array_get_idx(cur, 0);
 148                 if (!name || json_object_get_type(name) != json_type_string)
 149                         goto error;
 150
 151                 type = json_object_array_get_idx(cur, 1);
 152                 if (!type || json_object_get_type(type) != json_type_int)
 153                         goto error;
 154
 155                 attrs[i].name = json_object_get_string(name);
 156                 attrs[i].type = json_object_get_int(type);
 157                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 158                         goto error;
 159
 160                 str_len += strlen(attrs[i].name + 1);
 161         }
 162
 163         str_buf = malloc(str_len);
 164         if (!str_buf)
 165                 goto error;
 166
 167         str_cur = str_buf;
 168         for (i = 0; i < config->n_params; i++) {
 169                 const char *name = attrs[i].name;
 170
 171                 attrs[i].name = str_cur;
 172                 str_cur += sprintf(str_cur, "%s", name) + 1;
 173         }
 174
 175         return str_buf;
 176
 177 error:
 178         free(attrs);
 179         config->n_params = 0;
 180         return NULL;
 181 }
 182
 183 static void
 184 proto_shell_add_handler(const char *script, struct json_object *obj)
 185 {
 186         struct proto_shell_handler *handler;
 187         struct proto_handler *proto;
 188         json_object *config, *tmp;
 189         const char *name;
 190         char *str;
 191
 192         if (json_object_get_type(obj) != json_type_object)
 193                 return;
 194
 195         tmp = json_object_object_get(obj, "name");
 196         if (!tmp || json_object_get_type(tmp) != json_type_string)
 197                 return;
 198
 199         name = json_object_get_string(tmp);
 200
 201         handler = calloc(1, sizeof(*handler) +
 202                          strlen(script) + 1 +
 203                          strlen(name) + 1);
 204         if (!handler)
 205                 return;
 206
 207         strcpy(handler->script_name, script);
 208
 209         str = handler->script_name + strlen(handler->script_name) + 1;
 210         strcpy(str, name);
 211
 212         proto = &handler->proto;
 213         proto->name = str;
 214         proto->config_params = &handler->config;
 215         proto->attach = proto_shell_attach;
 216
 217         config = json_object_object_get(obj, "config");
 218         if (config && json_object_get_type(config) == json_type_array)
 219                 handler->config_buf = proto_shell_parse_config(&handler->config, config);
 220
 221         DPRINTF("Add handler for script %s: %s\n", script, proto->name);
 222         add_proto_handler(proto);
 223 }
 224
 225 static void proto_shell_add_script(const char *name)
 226 {
 227         struct json_tokener *tok = NULL;
 228         struct json_object *obj;
 229         static char buf[512];
 230         char *start, *end, *cmd;
 231         FILE *f;
 232         int buflen, len;
 233
 234         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
 235         sprintf(cmd, "%s" DUMP_SUFFIX, name);
 236
 237         f = popen(cmd, "r");
 238         if (!f)
 239                 return;
 240
 241         do {
 242                 buflen = fread(buf, 1, sizeof(buf) - 1, f);
 243                 if (buflen <= 0)
 244                         continue;
 245
 246                 start = buf;
 247                 len = buflen;
 248                 do {
 249                         end = memchr(start, '\n', len);
 250                         if (end)
 251                                 len = end - start;
 252
 253                         if (!tok)
 254                                 tok = json_tokener_new();
 255
 256                         obj = json_tokener_parse_ex(tok, start, len);
 257                         if (!is_error(obj)) {
 258                                 proto_shell_add_handler(name, obj);
 259                                 json_object_put(obj);
 260                                 json_tokener_free(tok);
 261                                 tok = NULL;
 262                         }
 263
 264                         if (end) {
 265                                 start = end + 1;
 266                                 len = buflen - (start - buf);
 267                         }
 268                 } while (len > 0);
 269         } while (!feof(f) && !ferror(f));
 270
 271         if (tok)
 272                 json_tokener_free(tok);
 273
 274         pclose(f);
 275 }
 276
 277 void __init proto_shell_init(void)
 278 {
 279         glob_t g;
 280         int main_fd;
 281         int i;
 282
 283         main_fd = open(".", O_RDONLY | O_DIRECTORY);
 284         if (main_fd < 0)
 285                 return;
 286
 287         if (chdir(main_path)) {
 288                 perror("chdir(main path)");
 289                 goto close_cur;
 290         }
 291
 292         if (chdir("./proto"))
 293                 goto close_cur;
 294
 295         proto_fd = open(".", O_RDONLY | O_DIRECTORY);
 296         if (proto_fd < 0)
 297                 goto close_cur;
 298
 299         glob("./*.sh", 0, NULL, &g);
 300         for (i = 0; i < g.gl_pathc; i++)
 301                 proto_shell_add_script(g.gl_pathv[i]);
 302
 303 close_cur:
 304         fchdir(main_fd);
 305         close(main_fd);
 306 }