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 enum {
  37         LOG_STDOUT,
  38         LOG_FILE,
  39         LOG_NET,
  40 };
  41
  42 enum {
  43         LOG_MSG,
  44         LOG_ID,
  45         LOG_PRIO,
  46         LOG_SOURCE,
  47         LOG_TIME,
  48         __LOG_MAX
  49 };
  50
  51 static const struct blobmsg_policy log_policy[] = {
  52         [LOG_MSG] = { .name = "msg", .type = BLOBMSG_TYPE_STRING },
  53         [LOG_ID] = { .name = "id", .type = BLOBMSG_TYPE_INT32 },
  54         [LOG_PRIO] = { .name = "priority", .type = BLOBMSG_TYPE_INT32 },
  55         [LOG_SOURCE] = { .name = "source", .type = BLOBMSG_TYPE_INT32 },
  56         [LOG_TIME] = { .name = "time", .type = BLOBMSG_TYPE_INT64 },
  57 };
  58
  59 static struct uloop_timeout retry;
  60 static struct uloop_fd sender;
  61 static regex_t regexp_preg;
  62 static const char *log_file, *log_ip, *log_port, *log_prefix, *pid_file, *hostname, *regexp_pattern;
  63 static int log_type = LOG_STDOUT;
  64 static int log_size, log_udp, log_follow, log_trailer_null = 0;
  65
  66 static const char* getcodetext(int value, CODE *codetable) {
  67         CODE *i;
  68
  69         if (value >= 0)
  70                 for (i = codetable; i->c_val != -1; i++)
  71                         if (i->c_val == value)
  72                                 return (i->c_name);
  73         return "<unknown>";
  74 };
  75
  76 static void log_handle_reconnect(struct uloop_timeout *timeout)
  77 {
  78         sender.fd = usock((log_udp) ? (USOCK_UDP) : (USOCK_TCP), log_ip, log_port);
  79         if (sender.fd < 0) {
  80                 fprintf(stderr, "failed to connect: %s\n", strerror(errno));
  81                 uloop_timeout_set(&retry, 1000);
  82         } else {
  83                 uloop_fd_add(&sender, ULOOP_READ);
  84                 syslog(LOG_INFO, "Logread connected to %s:%s\n", log_ip, log_port);
  85         }
  86 }
  87
  88 static void log_handle_fd(struct uloop_fd *u, unsigned int events)
  89 {
  90         if (u->eof) {
  91                 uloop_fd_delete(u);
  92                 close(sender.fd);
  93                 sender.fd = -1;
  94                 uloop_timeout_set(&retry, 1000);
  95         }
  96 }
  97
  98 static int log_notify(struct blob_attr *msg)
  99 {
 100         struct blob_attr *tb[__LOG_MAX];
 101         struct stat s;
 102         char buf[512];
 103         uint32_t p;
 104         char *str;
 105         time_t t;
 106         char *c, *m;
 107         int ret = 0;
 108
 109         if (sender.fd < 0)
 110                 return 0;
 111
 112         blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blob_data(msg), blob_len(msg));
 113         if (!tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME] || !tb[LOG_MSG])
 114                 return 1;
 115
 116         if ((log_type == LOG_FILE) && log_size && (!stat(log_file, &s)) && (s.st_size > log_size)) {
 117                 char *old = malloc(strlen(log_file) + 5);
 118
 119                 close(sender.fd);
 120                 if (old) {
 121                         sprintf(old, "%s.old", log_file);
 122                         rename(log_file, old);
 123                         free(old);
 124                 }
 125                 sender.fd = open(log_file, O_CREAT | O_WRONLY | O_APPEND, 0600);
 126                 if (sender.fd < 0) {
 127                         fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 128                         exit(-1);
 129                 }
 130         }
 131
 132         m = blobmsg_get_string(tb[LOG_MSG]);
 133         if (regexp_pattern &&
 134             regexec(&regexp_preg, m, 0, NULL, 0) == REG_NOMATCH)
 135                 return 0;
 136         t = blobmsg_get_u64(tb[LOG_TIME]) / 1000;
 137         c = ctime(&t);
 138         p = blobmsg_get_u32(tb[LOG_PRIO]);
 139         c[strlen(c) - 1] = '\0';
 140         str = blobmsg_format_json(msg, true);
 141         if (log_type == LOG_NET) {
 142                 int err;
 143
 144                 snprintf(buf, sizeof(buf), "<%u>", p);
 145                 strncat(buf, c + 4, 16);
 146                 if (hostname) {
 147                         strncat(buf, hostname, sizeof(buf) - strlen(buf) - 1);
 148                         strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
 149                 }
 150                 if (log_prefix) {
 151                         strncat(buf, log_prefix, sizeof(buf) - strlen(buf) - 1);
 152                         strncat(buf, ": ", sizeof(buf) - strlen(buf) - 1);
 153                 }
 154                 if (blobmsg_get_u32(tb[LOG_SOURCE]) == SOURCE_KLOG)
 155                         strncat(buf, "kernel: ", sizeof(buf) - strlen(buf) - 1);
 156                 strncat(buf, m, sizeof(buf) - strlen(buf) - 1);
 157                 if (log_udp)
 158                         err = write(sender.fd, buf, strlen(buf));
 159                 else {
 160                         size_t buflen = strlen(buf);
 161                         if (!log_trailer_null)
 162                                 buf[buflen] = '\n';
 163                         err = send(sender.fd, buf, buflen + 1, 0);
 164                 }
 165
 166                 if (err < 0) {
 167                         syslog(LOG_INFO, "failed to send log data to %s:%s via %s\n",
 168                                 log_ip, log_port, (log_udp) ? ("udp") : ("tcp"));
 169                         uloop_fd_delete(&sender);
 170                         close(sender.fd);
 171                         sender.fd = -1;
 172                         uloop_timeout_set(&retry, 1000);
 173                 }
 174         } else {
 175                 snprintf(buf, sizeof(buf), "%s %s.%s%s %s\n",
 176                         c, getcodetext(LOG_FAC(p) << 3, facilitynames), getcodetext(LOG_PRI(p), prioritynames),
 177                         (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"), m);
 178                 ret = write(sender.fd, buf, strlen(buf));
 179         }
 180
 181         free(str);
 182         if (log_type == LOG_FILE)
 183                 fsync(sender.fd);
 184
 185         return ret;
 186 }
 187
 188 static int usage(const char *prog)
 189 {
 190         fprintf(stderr, "Usage: %s [options]\n"
 191                 "Options:\n"
 192                 "    -s <path>          Path to ubus socket\n"
 193                 "    -l <count>         Got only the last 'count' messages\n"
 194                 "    -e <pattern>       Filter messages with a regexp\n"
 195                 "    -r <server> <port> Stream message to a server\n"
 196                 "    -F <file>          Log file\n"
 197                 "    -S <bytes>         Log size\n"
 198                 "    -p <file>          PID file\n"
 199                 "    -h <hostname>      Add hostname to the message\n"
 200                 "    -P <prefix>        Prefix custom text to streamed messages\n"
 201                 "    -f                 Follow log messages\n"
 202                 "    -u                 Use UDP as the protocol\n"
 203                 "    -0                 Use \\0 instead of \\n as trailer when using TCP\n"
 204                 "\n", prog);
 205         return 1;
 206 }
 207
 208 static void logread_fd_data_cb(struct ustream *s, int bytes)
 209 {
 210         while (true) {
 211                 struct blob_attr *a;
 212                 int len, cur_len;
 213
 214                 a = (void*) ustream_get_read_buf(s, &len);
 215                 if (len < sizeof(*a))
 216                         break;
 217
 218                 cur_len = blob_len(a) + sizeof(*a);
 219                 if (len < cur_len)
 220                         break;
 221
 222                 log_notify(a);
 223                 ustream_consume(s, cur_len);
 224         }
 225         if (!log_follow)
 226                 uloop_end();
 227 }
 228
 229 static void logread_fd_cb(struct ubus_request *req, int fd)
 230 {
 231         static struct ustream_fd test_fd;
 232
 233         test_fd.stream.notify_read = logread_fd_data_cb;
 234         ustream_fd_init(&test_fd, fd);
 235 }
 236
 237 int main(int argc, char **argv)
 238 {
 239         static struct ubus_request req;
 240         struct ubus_context *ctx;
 241         uint32_t id;
 242         const char *ubus_socket = NULL;
 243         int ch, ret, lines = 0;
 244         static struct blob_buf b;
 245         int tries = 5;
 246
 247         signal(SIGPIPE, SIG_IGN);
 248
 249         while ((ch = getopt(argc, argv, "u0fcs:l:r:F:p:S:P:h:e:")) != -1) {
 250                 switch (ch) {
 251                 case 'u':
 252                         log_udp = 1;
 253                         break;
 254                 case '0':
 255                         log_trailer_null = 1;
 256                         break;
 257                 case 's':
 258                         ubus_socket = optarg;
 259                         break;
 260                 case 'r':
 261                         log_ip = optarg++;
 262                         log_port = argv[optind++];
 263                         break;
 264                 case 'F':
 265                         log_file = optarg;
 266                         break;
 267                 case 'p':
 268                         pid_file = optarg;
 269                         break;
 270                 case 'P':
 271                         log_prefix = optarg;
 272                         break;
 273                 case 'f':
 274                         log_follow = 1;
 275                         break;
 276                 case 'l':
 277                         lines = atoi(optarg);
 278                         break;
 279                 case 'S':
 280                         log_size = atoi(optarg);
 281                         if (log_size < 1)
 282                                 log_size = 1;
 283                         log_size *= 1024;
 284                         break;
 285                 case 'h':
 286                         hostname = optarg;
 287                         break;
 288                 case 'e':
 289                         if (!regcomp(&regexp_preg, optarg, REG_NOSUB)) {
 290                                 regexp_pattern = optarg;
 291                         }
 292                         break;
 293                 default:
 294                         return usage(*argv);
 295                 }
 296         }
 297         uloop_init();
 298
 299         ctx = ubus_connect(ubus_socket);
 300         if (!ctx) {
 301                 fprintf(stderr, "Failed to connect to ubus\n");
 302                 return -1;
 303         }
 304         ubus_add_uloop(ctx);
 305
 306         /* ugly ugly ugly ... we need a real reconnect logic */
 307         do {
 308                 ret = ubus_lookup_id(ctx, "log", &id);
 309                 if (ret) {
 310                         fprintf(stderr, "Failed to find log object: %s\n", ubus_strerror(ret));
 311                         sleep(1);
 312                         continue;
 313                 }
 314
 315                 blob_buf_init(&b, 0);
 316                 blobmsg_add_u8(&b, "stream", 1);
 317                 if (lines)
 318                         blobmsg_add_u32(&b, "lines", lines);
 319                 else if (log_follow)
 320                         blobmsg_add_u32(&b, "lines", 0);
 321                 if (log_follow) {
 322                         if (pid_file) {
 323                                 FILE *fp = fopen(pid_file, "w+");
 324                                 if (fp) {
 325                                         fprintf(fp, "%d", getpid());
 326                                         fclose(fp);
 327                                 }
 328                         }
 329                 }
 330
 331                 if (log_ip && log_port) {
 332                         openlog("logread", LOG_PID, LOG_DAEMON);
 333                         log_type = LOG_NET;
 334                         sender.cb = log_handle_fd;
 335                         retry.cb = log_handle_reconnect;
 336                         uloop_timeout_set(&retry, 1000);
 337                 } else if (log_file) {
 338                         log_type = LOG_FILE;
 339                         sender.fd = open(log_file, O_CREAT | O_WRONLY| O_APPEND, 0600);
 340                         if (sender.fd < 0) {
 341                                 fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 342                                 exit(-1);
 343                         }
 344                 } else {
 345                         sender.fd = STDOUT_FILENO;
 346                 }
 347
 348                 ubus_invoke_async(ctx, id, "read", b.head, &req);
 349                 req.fd_cb = logread_fd_cb;
 350                 ubus_complete_request_async(ctx, &req);
 351
 352                 uloop_run();
 353                 ubus_free(ctx);
 354                 uloop_done();
 355
 356         } while (ret && tries--);
 357
 358         return ret;
 359 }