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 <stdio.h>
  21 #include <unistd.h>
  22 #include <sys/types.h>
  23 #include <sys/socket.h>
  24
  25 #define SYSLOG_NAMES
  26 #include <syslog.h>
  27
  28 #include <libubox/ustream.h>
  29 #include <libubox/blobmsg_json.h>
  30 #include <libubox/usock.h>
  31 #include <libubox/uloop.h>
  32 #include "libubus.h"
  33 #include "syslog.h"
  34
  35 enum {
  36         LOG_STDOUT,
  37         LOG_FILE,
  38         LOG_NET,
  39 };
  40
  41 enum {
  42         LOG_MSG,
  43         LOG_ID,
  44         LOG_PRIO,
  45         LOG_SOURCE,
  46         LOG_TIME,
  47         __LOG_MAX
  48 };
  49
  50 static const struct blobmsg_policy log_policy[] = {
  51         [LOG_MSG] = { .name = "msg", .type = BLOBMSG_TYPE_STRING },
  52         [LOG_ID] = { .name = "id", .type = BLOBMSG_TYPE_INT32 },
  53         [LOG_PRIO] = { .name = "priority", .type = BLOBMSG_TYPE_INT32 },
  54         [LOG_SOURCE] = { .name = "source", .type = BLOBMSG_TYPE_INT32 },
  55         [LOG_TIME] = { .name = "time", .type = BLOBMSG_TYPE_INT64 },
  56 };
  57
  58 static struct uloop_timeout retry;
  59 static struct uloop_fd sender;
  60 static const char *log_file, *log_ip, *log_port, *log_prefix, *pid_file, *hostname;
  61 static int log_type = LOG_STDOUT;
  62 static int log_size, log_udp, log_follow, log_trailer_null = 0;
  63
  64 static const char* getcodetext(int value, CODE *codetable) {
  65         CODE *i;
  66
  67         if (value >= 0)
  68                 for (i = codetable; i->c_val != -1; i++)
  69                         if (i->c_val == value)
  70                                 return (i->c_name);
  71         return "<unknown>";
  72 };
  73
  74 static void log_handle_reconnect(struct uloop_timeout *timeout)
  75 {
  76         sender.fd = usock((log_udp) ? (USOCK_UDP) : (USOCK_TCP), log_ip, log_port);
  77         if (sender.fd < 0) {
  78                 fprintf(stderr, "failed to connect: %s\n", strerror(errno));
  79                 uloop_timeout_set(&retry, 1000);
  80         } else {
  81                 uloop_fd_add(&sender, ULOOP_READ);
  82                 syslog(LOG_INFO, "Logread connected to %s:%s\n", log_ip, log_port);
  83         }
  84 }
  85
  86 static void log_handle_fd(struct uloop_fd *u, unsigned int events)
  87 {
  88         if (u->eof) {
  89                 uloop_fd_delete(u);
  90                 close(sender.fd);
  91                 sender.fd = -1;
  92                 uloop_timeout_set(&retry, 1000);
  93         }
  94 }
  95
  96 static int log_notify(struct blob_attr *msg)
  97 {
  98         struct blob_attr *tb[__LOG_MAX];
  99         struct stat s;
 100         char buf[512];
 101         uint32_t p;
 102         char *str;
 103         time_t t;
 104         char *c, *m;
 105         int ret = 0;
 106
 107         if (sender.fd < 0)
 108                 return 0;
 109
 110         blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blob_data(msg), blob_len(msg));
 111         if (!tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME] || !tb[LOG_MSG])
 112                 return 1;
 113
 114         if ((log_type == LOG_FILE) && log_size && (!stat(log_file, &s)) && (s.st_size > log_size)) {
 115                 char *old = malloc(strlen(log_file) + 5);
 116
 117                 close(sender.fd);
 118                 if (old) {
 119                         sprintf(old, "%s.old", log_file);
 120                         rename(log_file, old);
 121                         free(old);
 122                 }
 123                 sender.fd = open(log_file, O_CREAT | O_WRONLY | O_APPEND, 0600);
 124                 if (sender.fd < 0) {
 125                         fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 126                         exit(-1);
 127                 }
 128         }
 129
 130         m = blobmsg_get_string(tb[LOG_MSG]);
 131         t = blobmsg_get_u64(tb[LOG_TIME]) / 1000;
 132         c = ctime(&t);
 133         p = blobmsg_get_u32(tb[LOG_PRIO]);
 134         c[strlen(c) - 1] = '\0';
 135         str = blobmsg_format_json(msg, true);
 136         if (log_type == LOG_NET) {
 137                 int err;
 138
 139                 snprintf(buf, sizeof(buf), "<%u>", p);
 140                 strncat(buf, c + 4, 16);
 141                 if (hostname) {
 142                         strncat(buf, hostname, sizeof(buf) - strlen(buf) - 1);
 143                         strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
 144                 }
 145                 if (log_prefix) {
 146                         strncat(buf, log_prefix, sizeof(buf) - strlen(buf) - 1);
 147                         strncat(buf, ": ", sizeof(buf) - strlen(buf) - 1);
 148                 }
 149                 if (blobmsg_get_u32(tb[LOG_SOURCE]) == SOURCE_KLOG)
 150                         strncat(buf, "kernel: ", sizeof(buf) - strlen(buf) - 1);
 151                 strncat(buf, m, sizeof(buf) - strlen(buf) - 1);
 152                 if (log_udp)
 153                         err = write(sender.fd, buf, strlen(buf));
 154                 else {
 155                         size_t buflen = strlen(buf);
 156                         if (!log_trailer_null)
 157                                 buf[buflen] = '\n';
 158                         err = send(sender.fd, buf, buflen + 1, 0);
 159                 }
 160
 161                 if (err < 0) {
 162                         syslog(LOG_INFO, "failed to send log data to %s:%s via %s\n",
 163                                 log_ip, log_port, (log_udp) ? ("udp") : ("tcp"));
 164                         uloop_fd_delete(&sender);
 165                         close(sender.fd);
 166                         sender.fd = -1;
 167                         uloop_timeout_set(&retry, 1000);
 168                 }
 169         } else {
 170                 snprintf(buf, sizeof(buf), "%s %s.%s%s %s\n",
 171                         c, getcodetext(LOG_FAC(p) << 3, facilitynames), getcodetext(LOG_PRI(p), prioritynames),
 172                         (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"), m);
 173                 ret = write(sender.fd, buf, strlen(buf));
 174         }
 175
 176         free(str);
 177         if (log_type == LOG_FILE)
 178                 fsync(sender.fd);
 179
 180         return ret;
 181 }
 182
 183 static int usage(const char *prog)
 184 {
 185         fprintf(stderr, "Usage: %s [options]\n"
 186                 "Options:\n"
 187                 "    -s <path>          Path to ubus socket\n"
 188                 "    -l <count>         Got only the last 'count' messages\n"
 189                 "    -r <server> <port> Stream message to a server\n"
 190                 "    -F <file>          Log file\n"
 191                 "    -S <bytes>         Log size\n"
 192                 "    -p <file>          PID file\n"
 193                 "    -h <hostname>      Add hostname to the message\n"
 194                 "    -P <prefix>        Prefix custom text to streamed messages\n"
 195                 "    -f                 Follow log messages\n"
 196                 "    -u                 Use UDP as the protocol\n"
 197                 "    -0                 Use \\0 instead of \\n as trailer when using TCP\n"
 198                 "\n", prog);
 199         return 1;
 200 }
 201
 202 static void logread_fd_data_cb(struct ustream *s, int bytes)
 203 {
 204         while (true) {
 205                 int len;
 206                 struct blob_attr *a;
 207
 208                 a = (void*) ustream_get_read_buf(s, &len);
 209                 if (len < sizeof(*a) || len < blob_len(a) + sizeof(*a))
 210                         break;
 211                 log_notify(a);
 212                 ustream_consume(s, blob_len(a) + sizeof(*a));
 213         }
 214         if (!log_follow)
 215                 uloop_end();
 216 }
 217
 218 static void logread_fd_cb(struct ubus_request *req, int fd)
 219 {
 220         static struct ustream_fd test_fd;
 221
 222         test_fd.stream.notify_read = logread_fd_data_cb;
 223         ustream_fd_init(&test_fd, fd);
 224 }
 225
 226 static void logread_complete_cb(struct ubus_request *req, int ret)
 227 {
 228 }
 229
 230 int main(int argc, char **argv)
 231 {
 232         static struct ubus_request req;
 233         struct ubus_context *ctx;
 234         uint32_t id;
 235         const char *ubus_socket = NULL;
 236         int ch, ret, lines = 0;
 237         static struct blob_buf b;
 238         int tries = 5;
 239
 240         signal(SIGPIPE, SIG_IGN);
 241
 242         while ((ch = getopt(argc, argv, "u0fcs:l:r:F:p:S:P:h:")) != -1) {
 243                 switch (ch) {
 244                 case 'u':
 245                         log_udp = 1;
 246                         break;
 247                 case '0':
 248                         log_trailer_null = 1;
 249                         break;
 250                 case 's':
 251                         ubus_socket = optarg;
 252                         break;
 253                 case 'r':
 254                         log_ip = optarg++;
 255                         log_port = argv[optind++];
 256                         break;
 257                 case 'F':
 258                         log_file = optarg;
 259                         break;
 260                 case 'p':
 261                         pid_file = optarg;
 262                         break;
 263                 case 'P':
 264                         log_prefix = optarg;
 265                         break;
 266                 case 'f':
 267                         log_follow = 1;
 268                         break;
 269                 case 'l':
 270                         lines = atoi(optarg);
 271                         break;
 272                 case 'S':
 273                         log_size = atoi(optarg);
 274                         if (log_size < 1)
 275                                 log_size = 1;
 276                         log_size *= 1024;
 277                         break;
 278                 case 'h':
 279                         hostname = optarg;
 280                         break;
 281                 default:
 282                         return usage(*argv);
 283                 }
 284         }
 285         uloop_init();
 286
 287         ctx = ubus_connect(ubus_socket);
 288         if (!ctx) {
 289                 fprintf(stderr, "Failed to connect to ubus\n");
 290                 return -1;
 291         }
 292         ubus_add_uloop(ctx);
 293
 294         /* ugly ugly ugly ... we need a real reconnect logic */
 295         do {
 296                 ret = ubus_lookup_id(ctx, "log", &id);
 297                 if (ret) {
 298                         fprintf(stderr, "Failed to find log object: %s\n", ubus_strerror(ret));
 299                         sleep(1);
 300                         continue;
 301                 }
 302
 303                 blob_buf_init(&b, 0);
 304                 if (lines)
 305                         blobmsg_add_u32(&b, "lines", lines);
 306                 else if (log_follow)
 307                         blobmsg_add_u32(&b, "lines", 0);
 308                 if (log_follow) {
 309                         if (pid_file) {
 310                                 FILE *fp = fopen(pid_file, "w+");
 311                                 if (fp) {
 312                                         fprintf(fp, "%d", getpid());
 313                                         fclose(fp);
 314                                 }
 315                         }
 316                 }
 317
 318                 if (log_ip && log_port) {
 319                         openlog("logread", LOG_PID, LOG_DAEMON);
 320                         log_type = LOG_NET;
 321                         sender.cb = log_handle_fd;
 322                         retry.cb = log_handle_reconnect;
 323                         uloop_timeout_set(&retry, 1000);
 324                 } else if (log_file) {
 325                         log_type = LOG_FILE;
 326                         sender.fd = open(log_file, O_CREAT | O_WRONLY| O_APPEND, 0600);
 327                         if (sender.fd < 0) {
 328                                 fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 329                                 exit(-1);
 330                         }
 331                 } else {
 332                         sender.fd = STDOUT_FILENO;
 333                 }
 334
 335                 ubus_invoke_async(ctx, id, "read", b.head, &req);
 336                 req.fd_cb = logread_fd_cb;
 337                 req.complete_cb = logread_complete_cb;
 338                 ubus_complete_request_async(ctx, &req);
 339
 340                 uloop_run();
 341                 ubus_free(ctx);
 342                 uloop_done();
 343
 344         } while (ret && tries--);
 345
 346         return ret;
 347 }