log/logread.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17
  18 #include <fcntl.h>
  19 #include <time.h>
  20 #include <regex.h>
  21 #include <stdio.h>
  22 #include <unistd.h>
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25
  26 #define SYSLOG_NAMES
  27 #include <syslog.h>
  28
  29 #include <libubox/ustream.h>
  30 #include <libubox/blobmsg_json.h>
  31 #include <libubox/usock.h>
  32 #include <libubox/uloop.h>
  33 #include "libubus.h"
  34 #include "syslog.h"
  35
  36 #define LOGD_CONNECT_RETRY      10
  37
  38 enum {
  39         LOG_STDOUT,
  40         LOG_FILE,
  41         LOG_NET,
  42 };
  43
  44 enum {
  45         LOG_MSG,
  46         LOG_ID,
  47         LOG_PRIO,
  48         LOG_SOURCE,
  49         LOG_TIME,
  50         __LOG_MAX
  51 };
  52
  53 static const struct blobmsg_policy log_policy[] = {
  54         [LOG_MSG] = { .name = "msg", .type = BLOBMSG_TYPE_STRING },
  55         [LOG_ID] = { .name = "id", .type = BLOBMSG_TYPE_INT32 },
  56         [LOG_PRIO] = { .name = "priority", .type = BLOBMSG_TYPE_INT32 },
  57         [LOG_SOURCE] = { .name = "source", .type = BLOBMSG_TYPE_INT32 },
  58         [LOG_TIME] = { .name = "time", .type = BLOBMSG_TYPE_INT64 },
  59 };
  60
  61 static struct uloop_timeout retry;
  62 static struct uloop_fd sender;
  63 static regex_t regexp_preg;
  64 static const char *log_file, *log_ip, *log_port, *log_prefix, *pid_file, *hostname, *regexp_pattern;
  65 static int log_type = LOG_STDOUT;
  66 static int log_size, log_udp, log_follow, log_trailer_null = 0;
  67 static int log_timestamp;
  68 static int logd_conn_tries = LOGD_CONNECT_RETRY;
  69 static int facility_include;
  70 static int facility_exclude;
  71
  72 /* check for facility filter; return 0 if message shall be dropped */
  73 static int check_facility_filter(int f)
  74 {
  75         if (facility_include)
  76                 return !!(facility_include & (1 << f));
  77         if (facility_exclude)
  78                 return !(facility_exclude & (1 << f));
  79         return 1;
  80 }
  81
  82 static const char* getcodetext(int value, CODE *codetable) {
  83         CODE *i;
  84
  85         if (value >= 0)
  86                 for (i = codetable; i->c_val != -1; i++)
  87                         if (i->c_val == value)
  88                                 return (i->c_name);
  89         return "<unknown>";
  90 };
  91
  92 static void log_handle_reconnect(struct uloop_timeout *timeout)
  93 {
  94         sender.fd = usock((log_udp) ? (USOCK_UDP) : (USOCK_TCP), log_ip, log_port);
  95         if (sender.fd < 0) {
  96                 fprintf(stderr, "failed to connect: %m\n");
  97                 uloop_timeout_set(&retry, 1000);
  98         } else {
  99                 uloop_fd_add(&sender, ULOOP_READ);
 100                 syslog(LOG_INFO, "Logread connected to %s:%s\n", log_ip, log_port);
 101         }
 102 }
 103
 104 static void log_handle_fd(struct uloop_fd *u, unsigned int events)
 105 {
 106         if (u->eof) {
 107                 uloop_fd_delete(u);
 108                 close(sender.fd);
 109                 sender.fd = -1;
 110                 uloop_timeout_set(&retry, 1000);
 111         }
 112 }
 113
 114 static int log_notify(struct blob_attr *msg)
 115 {
 116         struct blob_attr *tb[__LOG_MAX];
 117         struct stat s;
 118         char buf[LOG_LINE_SIZE + 128];
 119         char buf_ts[32];
 120         uint32_t p;
 121         time_t t;
 122         uint32_t t_ms = 0;
 123         char *c, *m;
 124         int ret = 0;
 125
 126         if (sender.fd < 0)
 127                 return 0;
 128
 129         blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blob_data(msg), blob_len(msg));
 130         if (!tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME] || !tb[LOG_MSG])
 131                 return 1;
 132
 133         if ((log_type == LOG_FILE) && log_size && (!stat(log_file, &s)) && (s.st_size > log_size)) {
 134                 char *old = malloc(strlen(log_file) + 5);
 135
 136                 close(sender.fd);
 137                 if (old) {
 138                         sprintf(old, "%s.old", log_file);
 139                         rename(log_file, old);
 140                         free(old);
 141                 }
 142                 sender.fd = open(log_file, O_CREAT | O_WRONLY | O_APPEND, 0600);
 143                 if (sender.fd < 0) {
 144                         fprintf(stderr, "failed to open %s: %m\n", log_file);
 145                         exit(-1);
 146                 }
 147         }
 148         p = blobmsg_get_u32(tb[LOG_PRIO]);
 149
 150         if (!check_facility_filter(LOG_FAC(p)))
 151                         return 0;
 152
 153         m = blobmsg_get_string(tb[LOG_MSG]);
 154         if (regexp_pattern &&
 155             regexec(&regexp_preg, m, 0, NULL, 0) == REG_NOMATCH)
 156                 return 0;
 157         t = blobmsg_get_u64(tb[LOG_TIME]) / 1000;
 158         if (log_timestamp) {
 159                 t_ms = blobmsg_get_u64(tb[LOG_TIME]) % 1000;
 160                 snprintf(buf_ts, sizeof(buf_ts), "[%lu.%03u] ",
 161                                 (unsigned long)t, t_ms);
 162         }
 163         c = ctime(&t);
 164         c[strlen(c) - 1] = '\0';
 165
 166         if (log_type == LOG_NET) {
 167                 int err;
 168
 169                 snprintf(buf, sizeof(buf), "<%u>", p);
 170                 strncat(buf, c + 4, 16);
 171                 if (log_timestamp) {
 172                         strncat(buf, buf_ts, sizeof(buf) - strlen(buf) - 1);
 173                 }
 174                 if (hostname) {
 175                         strncat(buf, hostname, sizeof(buf) - strlen(buf) - 1);
 176                         strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
 177                 }
 178                 if (log_prefix) {
 179                         strncat(buf, log_prefix, sizeof(buf) - strlen(buf) - 1);
 180                         strncat(buf, ": ", sizeof(buf) - strlen(buf) - 1);
 181                 }
 182                 if (blobmsg_get_u32(tb[LOG_SOURCE]) == SOURCE_KLOG)
 183                         strncat(buf, "kernel: ", sizeof(buf) - strlen(buf) - 1);
 184                 strncat(buf, m, sizeof(buf) - strlen(buf) - 1);
 185                 if (log_udp)
 186                         err = write(sender.fd, buf, strlen(buf));
 187                 else {
 188                         size_t buflen = strlen(buf);
 189                         if (!log_trailer_null)
 190                                 buf[buflen] = '\n';
 191                         err = send(sender.fd, buf, buflen + 1, 0);
 192                 }
 193
 194                 if (err < 0) {
 195                         syslog(LOG_INFO, "failed to send log data to %s:%s via %s\n",
 196                                 log_ip, log_port, (log_udp) ? ("udp") : ("tcp"));
 197                         uloop_fd_delete(&sender);
 198                         close(sender.fd);
 199                         sender.fd = -1;
 200                         uloop_timeout_set(&retry, 1000);
 201                 }
 202         } else {
 203                 snprintf(buf, sizeof(buf), "%s %s%s.%s%s %s\n",
 204                         c, log_timestamp ? buf_ts : "",
 205                         getcodetext(LOG_FAC(p) << 3, facilitynames),
 206                         getcodetext(LOG_PRI(p), prioritynames),
 207                         (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"), m);
 208                 ret = write(sender.fd, buf, strlen(buf));
 209         }
 210
 211         if (log_type == LOG_FILE)
 212                 fsync(sender.fd);
 213
 214         return ret;
 215 }
 216
 217 static int usage(const char *prog)
 218 {
 219         fprintf(stderr, "Usage: %s [options]\n"
 220                 "Options:\n"
 221                 "    -s <path>          Path to ubus socket\n"
 222                 "    -l <count>         Got only the last 'count' messages\n"
 223                 "    -e <pattern>       Filter messages with a regexp\n"
 224                 "    -r <server> <port> Stream message to a server\n"
 225                 "    -F <file>          Log file\n"
 226                 "    -S <bytes>         Log size\n"
 227                 "    -p <file>          PID file\n"
 228                 "    -h <hostname>      Add hostname to the message\n"
 229                 "    -P <prefix>        Prefix custom text to streamed messages\n"
 230                 "    -z <facility>      handle only messages with given facility (0-23), repeatable\n"
 231                 "    -Z <facility>      ignore messages with given facility (0-23), repeatable\n"
 232                 "    -f                 Follow log messages\n"
 233                 "    -u                 Use UDP as the protocol\n"
 234                 "    -t                 Add an extra timestamp\n"
 235                 "    -0                 Use \\0 instead of \\n as trailer when using TCP\n"
 236                 "\n", prog);
 237         return 1;
 238 }
 239
 240 static void logread_fd_data_cb(struct ustream *s, int bytes)
 241 {
 242         while (true) {
 243                 struct blob_attr *a;
 244                 int len, cur_len;
 245
 246                 a = (void*) ustream_get_read_buf(s, &len);
 247                 if (len < sizeof(*a))
 248                         break;
 249
 250                 cur_len = blob_len(a) + sizeof(*a);
 251                 if (len < cur_len)
 252                         break;
 253
 254                 log_notify(a);
 255                 ustream_consume(s, cur_len);
 256         }
 257 }
 258
 259 static void logread_fd_state_cb(struct ustream *s)
 260 {
 261         if (log_follow)
 262                 logd_conn_tries = LOGD_CONNECT_RETRY;
 263         uloop_end();
 264 }
 265
 266 static void logread_fd_cb(struct ubus_request *req, int fd)
 267 {
 268         static struct ustream_fd test_fd;
 269
 270         memset(&test_fd, 0, sizeof(test_fd));
 271
 272         test_fd.stream.notify_read = logread_fd_data_cb;
 273         test_fd.stream.notify_state = logread_fd_state_cb;
 274         ustream_fd_init(&test_fd, fd);
 275 }
 276
 277 static void logread_setup_output(void)
 278 {
 279         if (sender.fd || sender.cb)
 280                 return;
 281
 282         if (log_ip && log_port) {
 283                 openlog("logread", LOG_PID, LOG_DAEMON);
 284                 log_type = LOG_NET;
 285                 sender.cb = log_handle_fd;
 286                 retry.cb = log_handle_reconnect;
 287                 uloop_timeout_set(&retry, 1000);
 288         } else if (log_file) {
 289                 log_type = LOG_FILE;
 290                 sender.fd = open(log_file, O_CREAT | O_WRONLY| O_APPEND, 0600);
 291                 if (sender.fd < 0) {
 292                         fprintf(stderr, "failed to open %s: %m\n", log_file);
 293                         exit(-1);
 294                 }
 295         } else {
 296                 sender.fd = STDOUT_FILENO;
 297         }
 298 }
 299
 300 int main(int argc, char **argv)
 301 {
 302         struct ubus_context *ctx;
 303         uint32_t id;
 304         const char *ubus_socket = NULL;
 305         int ch, ret, lines = 0;
 306         static struct blob_buf b;
 307
 308         signal(SIGPIPE, SIG_IGN);
 309
 310         while ((ch = getopt(argc, argv, "u0fcs:l:z:Z:r:F:p:S:P:h:e:t")) != -1) {
 311                 switch (ch) {
 312                 case 'u':
 313                         log_udp = 1;
 314                         break;
 315                 case '0':
 316                         log_trailer_null = 1;
 317                         break;
 318                 case 's':
 319                         ubus_socket = optarg;
 320                         break;
 321                 case 'r':
 322                         log_ip = optarg++;
 323                         log_port = argv[optind++];
 324                         break;
 325                 case 'F':
 326                         log_file = optarg;
 327                         break;
 328                 case 'p':
 329                         pid_file = optarg;
 330                         break;
 331                 case 'P':
 332                         log_prefix = optarg;
 333                         break;
 334                 case 'f':
 335                         log_follow = 1;
 336                         break;
 337                 case 'l':
 338                         lines = atoi(optarg);
 339                         break;
 340                 case 'z':
 341                         id = strtoul(optarg, NULL, 0) & 0x1f;
 342                         facility_include |= (1 << id);
 343                         break;
 344                 case 'Z':
 345                         id = strtoul(optarg, NULL, 0) & 0x1f;
 346                         facility_exclude |= (1 << id);
 347                         break;
 348                 case 'S':
 349                         log_size = atoi(optarg);
 350                         if (log_size < 1)
 351                                 log_size = 1;
 352                         log_size *= 1024;
 353                         break;
 354                 case 'h':
 355                         hostname = optarg;
 356                         break;
 357                 case 'e':
 358                         if (!regcomp(&regexp_preg, optarg, REG_NOSUB)) {
 359                                 regexp_pattern = optarg;
 360                         }
 361                         break;
 362                 case 't':
 363                         log_timestamp = 1;
 364                         break;
 365                 default:
 366                         return usage(*argv);
 367                 }
 368         }
 369         uloop_init();
 370
 371         ctx = ubus_connect(ubus_socket);
 372         if (!ctx) {
 373                 fprintf(stderr, "Failed to connect to ubus\n");
 374                 return -1;
 375         }
 376         ubus_add_uloop(ctx);
 377
 378         if (log_follow && pid_file) {
 379                 FILE *fp = fopen(pid_file, "w+");
 380                 if (fp) {
 381                         fprintf(fp, "%d", getpid());
 382                         fclose(fp);
 383                 }
 384         }
 385
 386         blob_buf_init(&b, 0);
 387         blobmsg_add_u8(&b, "stream", 1);
 388         blobmsg_add_u8(&b, "oneshot", !log_follow);
 389         if (lines)
 390                 blobmsg_add_u32(&b, "lines", lines);
 391         else if (log_follow)
 392                 blobmsg_add_u32(&b, "lines", 0);
 393
 394         /* ugly ugly ugly ... we need a real reconnect logic */
 395         do {
 396                 struct ubus_request req = { 0 };
 397
 398                 ret = ubus_lookup_id(ctx, "log", &id);
 399                 if (ret) {
 400                         fprintf(stderr, "Failed to find log object: %s\n", ubus_strerror(ret));
 401                         sleep(1);
 402                         continue;
 403                 }
 404                 logd_conn_tries = 0;
 405                 logread_setup_output();
 406
 407                 ubus_invoke_async(ctx, id, "read", b.head, &req);
 408                 req.fd_cb = logread_fd_cb;
 409                 ubus_complete_request_async(ctx, &req);
 410
 411                 uloop_run();
 412
 413         } while (logd_conn_tries--);
 414
 415         ubus_free(ctx);
 416         uloop_done();
 417
 418         if (log_follow && pid_file)
 419                 unlink(pid_file);
 420
 421         return ret;
 422 }