-/* userver.c - simple server for Unix domain sockets */
-
-/* Waits for a connection on the ./sample-socket Unix domain
- socket. Once a connection has been established, copy data
- from the socket to stdout until the other end closes the
- connection, and then wait for another connection to the socket. */
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini syslogd implementation for busybox
+ *
+ * Copyright (C) 1999,2000 by Lineo, inc. and Erik Andersen
+ * Copyright (C) 1999,2000,2001 by Erik Andersen <andersee@debian.org>
+ *
+ * Copyright (C) 2000 by Karl M. Hegbloom <karlheg@debian.org>
+ *
+ * "circular buffer" Copyright (C) 2001 by Gennady Feldman <gfeldman@cachier.com>
+ *
+ * Maintainer: Gennady Feldman <gena01@cachier.com> as of Mar 12, 2001
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <paths.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <time.h>
+#include <string.h>
+#include <unistd.h>
#include <sys/socket.h>
+#include <sys/types.h>
#include <sys/un.h>
-#include <unistd.h>
+#include <sys/param.h>
+
+#include "busybox.h"
+
+/* SYSLOG_NAMES defined to pull some extra junk from syslog.h */
+#define SYSLOG_NAMES
+#include <sys/syslog.h>
+#include <sys/uio.h>
+
+/* Path for the file where all log messages are written */
+#define __LOG_FILE "/var/log/messages"
+
+/* Path to the unix socket */
+static char lfile[MAXPATHLEN];
+
+static char *logFilePath = __LOG_FILE;
+
+/* interval between marks in seconds */
+static int MarkInterval = 20 * 60;
+
+/* localhost's name */
+static char LocalHostName[64];
+
+#ifdef CONFIG_FEATURE_REMOTE_LOG
+#include <netinet/in.h>
+/* udp socket for logging to remote host */
+static int remotefd = -1;
+
+/* where do we log? */
+static char *RemoteHost;
-#define _PATH_LOG "/dev/log"
+/* what port to log to? */
+static int RemotePort = 514;
+/* To remote log or not to remote log, that is the question. */
+static int doRemoteLog = FALSE;
+static int local_logging = FALSE;
+#endif
-/* issue an error message via perror() and terminate the program */
-void die(char * message) {
- perror(message);
- exit(1);
+
+#define MAXLINE 1024 /* maximum line length */
+
+
+/* circular buffer variables/structures */
+#ifdef CONFIG_FEATURE_IPC_SYSLOG
+#if __GNU_LIBRARY__ < 5
+#error Sorry. Looks like you are using libc5.
+#error libc5 shm support isnt good enough.
+#error Please disable CONFIG_FEATURE_IPC_SYSLOG
+#endif
+
+#include <sys/ipc.h>
+#include <sys/sem.h>
+#include <sys/shm.h>
+
+/* our shared key */
+static const long KEY_ID = 0x414e4547; /*"GENA" */
+
+// Semaphore operation structures
+static struct shbuf_ds {
+ int size; // size of data written
+ int head; // start of message list
+ int tail; // end of message list
+ char data[1]; // data/messages
+} *buf = NULL; // shared memory pointer
+
+static struct sembuf SMwup[1] = { {1, -1, IPC_NOWAIT} }; // set SMwup
+static struct sembuf SMwdn[3] = { {0, 0}, {1, 0}, {1, +1} }; // set SMwdn
+
+static int shmid = -1; // ipc shared memory id
+static int s_semid = -1; // ipc semaphore id
+int data_size = 16000; // data size
+int shm_size = 16000 + sizeof(*buf); // our buffer size
+static int circular_logging = FALSE;
+
+/*
+ * sem_up - up()'s a semaphore.
+ */
+static inline void sem_up(int semid)
+{
+ if (semop(semid, SMwup, 1) == -1) {
+ perror_msg_and_die("semop[SMwup]");
+ }
}
-/* Copies data from file descriptor 'from' to file descriptor 'to'
- until nothing is left to be copied. Exits if an error occurs. */
-void copyData(int from, int to) {
- char buf[1024];
- int amount;
-
- while ((amount = read(from, buf, sizeof(buf))) > 0) {
- if (write(to, buf, amount) != amount) {
- die("write");
- return;
- }
- }
- if (amount < 0)
- die("read");
+/*
+ * sem_down - down()'s a semaphore
+ */
+static inline void sem_down(int semid)
+{
+ if (semop(semid, SMwdn, 3) == -1) {
+ perror_msg_and_die("semop[SMwdn]");
+ }
}
-int main(void) {
- struct sockaddr_un address;
- int fd, conn;
- size_t addrLength;
+void ipcsyslog_cleanup(void)
+{
+ printf("Exiting Syslogd!\n");
+ if (shmid != -1) {
+ shmdt(buf);
+ }
- /* Remove any preexisting socket (or other file) */
- unlink(_PATH_LOG);
+ if (shmid != -1) {
+ shmctl(shmid, IPC_RMID, NULL);
+ }
+ if (s_semid != -1) {
+ semctl(s_semid, 0, IPC_RMID, 0);
+ }
+}
- memset(&address, 0, sizeof(address));
- address.sun_family = AF_UNIX; /* Unix domain socket */
- strncpy(address.sun_path, _PATH_LOG, sizeof(address.sun_path));
+void ipcsyslog_init(void)
+{
+ if (buf == NULL) {
+ if ((shmid = shmget(KEY_ID, shm_size, IPC_CREAT | 1023)) == -1) {
+ perror_msg_and_die("shmget");
+ }
- if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
- die("socket");
+ if ((buf = shmat(shmid, NULL, 0)) == NULL) {
+ perror_msg_and_die("shmat");
+ }
+ buf->size = data_size;
+ buf->head = buf->tail = 0;
- /* The total length of the address includes the sun_family
- element */
- addrLength = sizeof(address.sun_family) +
- strlen(address.sun_path);
+ // we'll trust the OS to set initial semval to 0 (let's hope)
+ if ((s_semid = semget(KEY_ID, 2, IPC_CREAT | IPC_EXCL | 1023)) == -1) {
+ if (errno == EEXIST) {
+ if ((s_semid = semget(KEY_ID, 2, 0)) == -1) {
+ perror_msg_and_die("semget");
+ }
+ } else {
+ perror_msg_and_die("semget");
+ }
+ }
+ } else {
+ printf("Buffer already allocated just grab the semaphore?");
+ }
+}
- if (bind(fd, (struct sockaddr *) &address, addrLength))
- die("bind");
+/* write message to buffer */
+void circ_message(const char *msg)
+{
+ int l = strlen(msg) + 1; /* count the whole message w/ '\0' included */
- if (chmod(_PATH_LOG, 0666) < 0)
- die("chmod");
+ sem_down(s_semid);
- if (listen(fd, 5))
- die("listen");
+ /*
+ * Circular Buffer Algorithm:
+ * --------------------------
+ *
+ * Start-off w/ empty buffer of specific size SHM_SIZ
+ * Start filling it up w/ messages. I use '\0' as separator to break up messages.
+ * This is also very handy since we can do printf on message.
+ *
+ * Once the buffer is full we need to get rid of the first message in buffer and
+ * insert the new message. (Note: if the message being added is >1 message then
+ * we will need to "remove" >1 old message from the buffer). The way this is done
+ * is the following:
+ * When we reach the end of the buffer we set a mark and start from the beginning.
+ * Now what about the beginning and end of the buffer? Well we have the "head"
+ * index/pointer which is the starting point for the messages and we have "tail"
+ * index/pointer which is the ending point for the messages. When we "display" the
+ * messages we start from the beginning and continue until we reach "tail". If we
+ * reach end of buffer, then we just start from the beginning (offset 0). "head" and
+ * "tail" are actually offsets from the beginning of the buffer.
+ *
+ * Note: This algorithm uses Linux IPC mechanism w/ shared memory and semaphores to provide
+ * a threasafe way of handling shared memory operations.
+ */
+ if ((buf->tail + l) < buf->size) {
+ /* before we append the message we need to check the HEAD so that we won't
+ overwrite any of the message that we still need and adjust HEAD to point
+ to the next message! */
+ if (buf->tail < buf->head) {
+ if ((buf->tail + l) >= buf->head) {
+ /* we need to move the HEAD to point to the next message
+ * Theoretically we have enough room to add the whole message to the
+ * buffer, because of the first outer IF statement, so we don't have
+ * to worry about overflows here!
+ */
+ int k = buf->tail + l - buf->head; /* we need to know how many bytes
+ we are overwriting to make
+ enough room */
+ char *c =
+ memchr(buf->data + buf->head + k, '\0',
+ buf->size - (buf->head + k));
+ if (c != NULL) { /* do a sanity check just in case! */
+ buf->head = c - buf->data + 1; /* we need to convert pointer to
+ offset + skip the '\0' since
+ we need to point to the beginning
+ of the next message */
+ /* Note: HEAD is only used to "retrieve" messages, it's not used
+ when writing messages into our buffer */
+ } else { /* show an error message to know we messed up? */
+ printf("Weird! Can't find the terminator token??? \n");
+ buf->head = 0;
+ }
+ }
+ }
+ /* in other cases no overflows have been done yet, so we don't care! */
+ /* we should be ok to append the message now */
+ strncpy(buf->data + buf->tail, msg, l); /* append our message */
+ buf->tail += l; /* count full message w/ '\0' terminating char */
+ } else {
+ /* we need to break up the message and "circle" it around */
+ char *c;
+ int k = buf->tail + l - buf->size; /* count # of bytes we don't fit */
- while ((conn = accept(fd, (struct sockaddr *) &address,
- &addrLength)) >= 0) {
- printf("---- getting data\n");
- copyData(conn, fileno(stdout));
- printf("---- done\n");
- close(conn);
- }
+ /* We need to move HEAD! This is always the case since we are going
+ * to "circle" the message.
+ */
+ c = memchr(buf->data + k, '\0', buf->size - k);
- if (conn < 0)
- die("accept");
-
- close(fd);
- return 0;
+ if (c != NULL) { /* if we don't have '\0'??? weird!!! */
+ /* move head pointer */
+ buf->head = c - buf->data + 1;
+
+ /* now write the first part of the message */
+ strncpy(buf->data + buf->tail, msg, l - k - 1);
+
+ /* ALWAYS terminate end of buffer w/ '\0' */
+ buf->data[buf->size - 1] = '\0';
+
+ /* now write out the rest of the string to the beginning of the buffer */
+ strcpy(buf->data, &msg[l - k - 1]);
+
+ /* we need to place the TAIL at the end of the message */
+ buf->tail = k + 1;
+ } else {
+ printf
+ ("Weird! Can't find the terminator token from the beginning??? \n");
+ buf->head = buf->tail = 0; /* reset buffer, since it's probably corrupted */
+ }
+
+ }
+ sem_up(s_semid);
+}
+#endif /* CONFIG_FEATURE_IPC_SYSLOG */
+
+/* Note: There is also a function called "message()" in init.c */
+/* Print a message to the log file. */
+static void message(char *fmt, ...) __attribute__ ((format(printf, 1, 2)));
+static void message(char *fmt, ...)
+{
+ int fd;
+ struct flock fl;
+ va_list arguments;
+
+ fl.l_whence = SEEK_SET;
+ fl.l_start = 0;
+ fl.l_len = 1;
+
+#ifdef CONFIG_FEATURE_IPC_SYSLOG
+ if ((circular_logging == TRUE) && (buf != NULL)) {
+ char b[1024];
+
+ va_start(arguments, fmt);
+ vsnprintf(b, sizeof(b) - 1, fmt, arguments);
+ va_end(arguments);
+ circ_message(b);
+
+ } else
+#endif
+ if ((fd =
+ device_open(logFilePath,
+ O_WRONLY | O_CREAT | O_NOCTTY | O_APPEND |
+ O_NONBLOCK)) >= 0) {
+ fl.l_type = F_WRLCK;
+ fcntl(fd, F_SETLKW, &fl);
+ va_start(arguments, fmt);
+ vdprintf(fd, fmt, arguments);
+ va_end(arguments);
+ fl.l_type = F_UNLCK;
+ fcntl(fd, F_SETLKW, &fl);
+ close(fd);
+ } else {
+ /* Always send console messages to /dev/console so people will see them. */
+ if ((fd =
+ device_open(_PATH_CONSOLE,
+ O_WRONLY | O_NOCTTY | O_NONBLOCK)) >= 0) {
+ va_start(arguments, fmt);
+ vdprintf(fd, fmt, arguments);
+ va_end(arguments);
+ close(fd);
+ } else {
+ fprintf(stderr, "Bummer, can't print: ");
+ va_start(arguments, fmt);
+ vfprintf(stderr, fmt, arguments);
+ fflush(stderr);
+ va_end(arguments);
+ }
+ }
}
+static void logMessage(int pri, char *msg)
+{
+ time_t now;
+ char *timestamp;
+ static char res[20] = "";
+ CODE *c_pri, *c_fac;
+ if (pri != 0) {
+ for (c_fac = facilitynames;
+ c_fac->c_name && !(c_fac->c_val == LOG_FAC(pri) << 3); c_fac++);
+ for (c_pri = prioritynames;
+ c_pri->c_name && !(c_pri->c_val == LOG_PRI(pri)); c_pri++);
+ if (c_fac->c_name == NULL || c_pri->c_name == NULL) {
+ snprintf(res, sizeof(res), "<%d>", pri);
+ } else {
+ snprintf(res, sizeof(res), "%s.%s", c_fac->c_name, c_pri->c_name);
+ }
+ }
+
+ if (strlen(msg) < 16 || msg[3] != ' ' || msg[6] != ' ' ||
+ msg[9] != ':' || msg[12] != ':' || msg[15] != ' ') {
+ time(&now);
+ timestamp = ctime(&now) + 4;
+ timestamp[15] = '\0';
+ } else {
+ timestamp = msg;
+ timestamp[15] = '\0';
+ msg += 16;
+ }
+
+ /* todo: supress duplicates */
+
+#ifdef CONFIG_FEATURE_REMOTE_LOG
+ /* send message to remote logger */
+ if (-1 != remotefd) {
+ static const int IOV_COUNT = 2;
+ struct iovec iov[IOV_COUNT];
+ struct iovec *v = iov;
+
+ memset(&res, 0, sizeof(res));
+ snprintf(res, sizeof(res), "<%d>", pri);
+ v->iov_base = res;
+ v->iov_len = strlen(res);
+ v++;
+
+ v->iov_base = msg;
+ v->iov_len = strlen(msg);
+ writev_retry:
+ if (-1 == writev(remotefd, iov, IOV_COUNT)) {
+ if (errno == EINTR) {
+ goto writev_retry;
+ }
+ error_msg_and_die("cannot write to remote file handle on %s:%d",
+ RemoteHost, RemotePort);
+ }
+ }
+ if (local_logging == TRUE)
+#endif
+ /* now spew out the message to wherever it is supposed to go */
+ message("%s %s %s %s\n", timestamp, LocalHostName, res, msg);
+}
+
+static void quit_signal(int sig)
+{
+ logMessage(LOG_SYSLOG | LOG_INFO, "System log daemon exiting.");
+ unlink(lfile);
+#ifdef CONFIG_FEATURE_IPC_SYSLOG
+ ipcsyslog_cleanup();
+#endif
+
+ exit(TRUE);
+}
+
+static void domark(int sig)
+{
+ if (MarkInterval > 0) {
+ logMessage(LOG_SYSLOG | LOG_INFO, "-- MARK --");
+ alarm(MarkInterval);
+ }
+}
+
+/* This must be a #define, since when DODEBUG and BUFFERS_GO_IN_BSS are
+ * enabled, we otherwise get a "storage size isn't constant error. */
+static int serveConnection(char *tmpbuf, int n_read)
+{
+ char *p = tmpbuf;
+
+ while (p < tmpbuf + n_read) {
+
+ int pri = (LOG_USER | LOG_NOTICE);
+ char line[MAXLINE + 1];
+ unsigned char c;
+
+ char *q = line;
+
+ while ((c = *p) && q < &line[sizeof(line) - 1]) {
+ if (c == '<') {
+ /* Parse the magic priority number. */
+ pri = 0;
+ while (isdigit(*(++p))) {
+ pri = 10 * pri + (*p - '0');
+ }
+ if (pri & ~(LOG_FACMASK | LOG_PRIMASK)) {
+ pri = (LOG_USER | LOG_NOTICE);
+ }
+ } else if (c == '\n') {
+ *q++ = ' ';
+ } else if (iscntrl(c) && (c < 0177)) {
+ *q++ = '^';
+ *q++ = c ^ 0100;
+ } else {
+ *q++ = c;
+ }
+ p++;
+ }
+ *q = '\0';
+ p++;
+ /* Now log it */
+ logMessage(pri, line);
+ }
+ return n_read;
+}
+
+
+#ifdef CONFIG_FEATURE_REMOTE_LOG
+static void init_RemoteLog(void)
+{
+
+ struct sockaddr_in remoteaddr;
+ struct hostent *hostinfo;
+ int len = sizeof(remoteaddr);
+
+ memset(&remoteaddr, 0, len);
+
+ remotefd = socket(AF_INET, SOCK_DGRAM, 0);
+
+ if (remotefd < 0) {
+ error_msg_and_die("cannot create socket");
+ }
+
+ hostinfo = xgethostbyname(RemoteHost);
+
+ remoteaddr.sin_family = AF_INET;
+ remoteaddr.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
+ remoteaddr.sin_port = htons(RemotePort);
+
+ /* Since we are using UDP sockets, connect just sets the default host and port
+ * for future operations
+ */
+ if (0 != (connect(remotefd, (struct sockaddr *) &remoteaddr, len))) {
+ error_msg_and_die("cannot connect to remote host %s:%d", RemoteHost,
+ RemotePort);
+ }
+
+}
+#endif
+
+static void doSyslogd(void) __attribute__ ((noreturn));
+static void doSyslogd(void)
+{
+ struct sockaddr_un sunx;
+ socklen_t addrLength;
+
+ int sock_fd;
+ fd_set fds;
+
+ /* Set up signal handlers. */
+ signal(SIGINT, quit_signal);
+ signal(SIGTERM, quit_signal);
+ signal(SIGQUIT, quit_signal);
+ signal(SIGHUP, SIG_IGN);
+ signal(SIGCHLD, SIG_IGN);
+#ifdef SIGCLD
+ signal(SIGCLD, SIG_IGN);
+#endif
+ signal(SIGALRM, domark);
+ alarm(MarkInterval);
+
+ /* Create the syslog file so realpath() can work. */
+ if (realpath(_PATH_LOG, lfile) != NULL) {
+ unlink(lfile);
+ }
+
+ memset(&sunx, 0, sizeof(sunx));
+ sunx.sun_family = AF_UNIX;
+ strncpy(sunx.sun_path, lfile, sizeof(sunx.sun_path));
+ if ((sock_fd = socket(AF_UNIX, SOCK_DGRAM, 0)) < 0) {
+ perror_msg_and_die("Couldn't get file descriptor for socket "
+ _PATH_LOG);
+ }
+
+ addrLength = sizeof(sunx.sun_family) + strlen(sunx.sun_path);
+ if (bind(sock_fd, (struct sockaddr *) &sunx, addrLength) < 0) {
+ perror_msg_and_die("Could not connect to socket " _PATH_LOG);
+ }
+
+ if (chmod(lfile, 0666) < 0) {
+ perror_msg_and_die("Could not set permission on " _PATH_LOG);
+ }
+#ifdef CONFIG_FEATURE_IPC_SYSLOG
+ if (circular_logging == TRUE) {
+ ipcsyslog_init();
+ }
+#endif
+
+#ifdef CONFIG_FEATURE_REMOTE_LOG
+ if (doRemoteLog == TRUE) {
+ init_RemoteLog();
+ }
+#endif
+
+ logMessage(LOG_SYSLOG | LOG_INFO, "syslogd started: " BB_BANNER);
+
+ for (;;) {
+
+ FD_ZERO(&fds);
+ FD_SET(sock_fd, &fds);
+
+ if (select(sock_fd + 1, &fds, NULL, NULL, NULL) < 0) {
+ if (errno == EINTR) {
+ /* alarm may have happened. */
+ continue;
+ }
+ perror_msg_and_die("select error");
+ }
+
+ if (FD_ISSET(sock_fd, &fds)) {
+ int i;
+
+ RESERVE_CONFIG_BUFFER(tmpbuf, BUFSIZ + 1);
+
+ memset(tmpbuf, '\0', BUFSIZ + 1);
+ if ((i = recv(sock_fd, tmpbuf, BUFSIZ, 0)) > 0) {
+ serveConnection(tmpbuf, i);
+ } else {
+ perror_msg_and_die("UNIX socket error");
+ }
+ RELEASE_CONFIG_BUFFER(tmpbuf);
+ } /* FD_ISSET() */
+ } /* for main loop */
+}
+
+extern int syslogd_main(int argc, char **argv)
+{
+ int opt;
+
+#if ! defined(__uClinux__)
+ int doFork = TRUE;
+#endif
+
+ char *p;
+
+ /* do normal option parsing */
+ while ((opt = getopt(argc, argv, "m:nO:R:LC")) > 0) {
+ switch (opt) {
+ case 'm':
+ MarkInterval = atoi(optarg) * 60;
+ break;
+#if ! defined(__uClinux__)
+ case 'n':
+ doFork = FALSE;
+ break;
+#endif
+ case 'O':
+ logFilePath = xstrdup(optarg);
+ break;
+#ifdef CONFIG_FEATURE_REMOTE_LOG
+ case 'R':
+ RemoteHost = xstrdup(optarg);
+ if ((p = strchr(RemoteHost, ':'))) {
+ RemotePort = atoi(p + 1);
+ *p = '\0';
+ }
+ doRemoteLog = TRUE;
+ break;
+ case 'L':
+ local_logging = TRUE;
+ break;
+#endif
+#ifdef CONFIG_FEATURE_IPC_SYSLOG
+ case 'C':
+ circular_logging = TRUE;
+ break;
+#endif
+ default:
+ show_usage();
+ }
+ }
+
+#ifdef CONFIG_FEATURE_REMOTE_LOG
+ /* If they have not specified remote logging, then log locally */
+ if (doRemoteLog == FALSE)
+ local_logging = TRUE;
+#endif
+
+
+ /* Store away localhost's name before the fork */
+ gethostname(LocalHostName, sizeof(LocalHostName));
+ if ((p = strchr(LocalHostName, '.'))) {
+ *p++ = '\0';
+ }
+
+ umask(0);
+
+#if ! defined(__uClinux__)
+ if ((doFork == TRUE) && (daemon(0, 1) < 0)) {
+ perror_msg_and_die("daemon");
+ }
+#endif
+ doSyslogd();
+
+ return EXIT_SUCCESS;
+}
+/*
+Local Variables
+c-file-style: "linux"
+c-basic-offset: 4
+tab-width: 4
+End:
+*/