1 files changed, 435 insertions, 0 deletions

diff --git a/lib/libc/gen/syslog.c b/lib/libc/gen/syslog.c
new file mode 100644
index 0000000..594fb97
--- /dev/null
+++ b/lib/libc/gen/syslog.c
@@ -0,0 +1,435 @@
+/*
+ * Copyright (c) 1983, 1988, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)syslog.c	8.5 (Berkeley) 4/29/95";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "namespace.h"
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/syslog.h>
+#include <sys/uio.h>
+#include <sys/un.h>
+#include <netdb.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <paths.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <stdarg.h>
+#include "un-namespace.h"
+
+#include "libc_private.h"
+
+static int	LogFile = -1;		/* fd for log */
+static int	status;			/* connection status */
+static int	opened;			/* have done openlog() */
+static int	LogStat = 0;		/* status bits, set by openlog() */
+static const char *LogTag = NULL;	/* string to tag the entry with */
+static int	LogFacility = LOG_USER;	/* default facility code */
+static int	LogMask = 0xff;		/* mask of priorities to be logged */
+static pthread_mutex_t	syslog_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+#define	THREAD_LOCK()							\
+	do { 								\
+		if (__isthreaded) _pthread_mutex_lock(&syslog_mutex);	\
+	} while(0)
+#define	THREAD_UNLOCK()							\
+	do {								\
+		if (__isthreaded) _pthread_mutex_unlock(&syslog_mutex);	\
+	} while(0)
+
+static void	disconnectlog(void); /* disconnect from syslogd */
+static void	connectlog(void);	/* (re)connect to syslogd */
+static void	openlog_unlocked(const char *, int, int);
+
+enum {
+	NOCONN = 0,
+	CONNDEF,
+	CONNPRIV,
+};
+
+/*
+ * Format of the magic cookie passed through the stdio hook
+ */
+struct bufcookie {
+	char	*base;	/* start of buffer */
+	int	left;
+};
+
+/*
+ * stdio write hook for writing to a static string buffer
+ * XXX: Maybe one day, dynamically allocate it so that the line length
+ *      is `unlimited'.
+ */
+static int
+writehook(void *cookie, const char *buf, int len)
+{
+	struct bufcookie *h;	/* private `handle' */
+
+	h = (struct bufcookie *)cookie;
+	if (len > h->left) {
+		/* clip in case of wraparound */
+		len = h->left;
+	}
+	if (len > 0) {
+		(void)memcpy(h->base, buf, len); /* `write' it. */
+		h->base += len;
+		h->left -= len;
+	}
+	return len;
+}
+
+/*
+ * syslog, vsyslog --
+ *	print message on log file; output is intended for syslogd(8).
+ */
+void
+syslog(int pri, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vsyslog(pri, fmt, ap);
+	va_end(ap);
+}
+
+void
+vsyslog(int pri, const char *fmt, va_list ap)
+{
+	int cnt;
+	char ch, *p;
+	time_t now;
+	int fd, saved_errno;
+	char *stdp, tbuf[2048], fmt_cpy[1024], timbuf[26], errstr[64];
+	FILE *fp, *fmt_fp;
+	struct bufcookie tbuf_cookie;
+	struct bufcookie fmt_cookie;
+
+#define	INTERNALLOG	LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID
+	/* Check for invalid bits. */
+	if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) {
+		syslog(INTERNALLOG,
+		    "syslog: unknown facility/priority: %x", pri);
+		pri &= LOG_PRIMASK|LOG_FACMASK;
+	}
+
+	saved_errno = errno;
+
+	THREAD_LOCK();
+
+	/* Check priority against setlogmask values. */
+	if (!(LOG_MASK(LOG_PRI(pri)) & LogMask)) {
+		THREAD_UNLOCK();
+		return;
+	}
+
+	/* Set default facility if none specified. */
+	if ((pri & LOG_FACMASK) == 0)
+		pri |= LogFacility;
+
+	/* Create the primary stdio hook */
+	tbuf_cookie.base = tbuf;
+	tbuf_cookie.left = sizeof(tbuf);
+	fp = fwopen(&tbuf_cookie, writehook);
+	if (fp == NULL) {
+		THREAD_UNLOCK();
+		return;
+	}
+
+	/* Build the message. */
+	(void)time(&now);
+	(void)fprintf(fp, "<%d>", pri);
+	(void)fprintf(fp, "%.15s ", ctime_r(&now, timbuf) + 4);
+	if (LogStat & LOG_PERROR) {
+		/* Transfer to string buffer */
+		(void)fflush(fp);
+		stdp = tbuf + (sizeof(tbuf) - tbuf_cookie.left);
+	}
+	if (LogTag == NULL)
+		LogTag = _getprogname();
+	if (LogTag != NULL)
+		(void)fprintf(fp, "%s", LogTag);
+	if (LogStat & LOG_PID)
+		(void)fprintf(fp, "[%d]", getpid());
+	if (LogTag != NULL) {
+		(void)fprintf(fp, ": ");
+	}
+
+	/* Check to see if we can skip expanding the %m */
+	if (strstr(fmt, "%m")) {
+
+		/* Create the second stdio hook */
+		fmt_cookie.base = fmt_cpy;
+		fmt_cookie.left = sizeof(fmt_cpy) - 1;
+		fmt_fp = fwopen(&fmt_cookie, writehook);
+		if (fmt_fp == NULL) {
+			fclose(fp);
+			THREAD_UNLOCK();
+			return;
+		}
+
+		/*
+		 * Substitute error message for %m.  Be careful not to
+		 * molest an escaped percent "%%m".  We want to pass it
+		 * on untouched as the format is later parsed by vfprintf.
+		 */
+		for ( ; (ch = *fmt); ++fmt) {
+			if (ch == '%' && fmt[1] == 'm') {
+				++fmt;
+				strerror_r(saved_errno, errstr, sizeof(errstr));
+				fputs(errstr, fmt_fp);
+			} else if (ch == '%' && fmt[1] == '%') {
+				++fmt;
+				fputc(ch, fmt_fp);
+				fputc(ch, fmt_fp);
+			} else {
+				fputc(ch, fmt_fp);
+			}
+		}
+
+		/* Null terminate if room */
+		fputc(0, fmt_fp);
+		fclose(fmt_fp);
+
+		/* Guarantee null termination */
+		fmt_cpy[sizeof(fmt_cpy) - 1] = '\0';
+
+		fmt = fmt_cpy;
+	}
+
+	(void)vfprintf(fp, fmt, ap);
+	(void)fclose(fp);
+
+	cnt = sizeof(tbuf) - tbuf_cookie.left;
+
+	/* Remove a trailing newline */
+	if (tbuf[cnt - 1] == '\n')
+		cnt--;
+
+	/* Output to stderr if requested. */
+	if (LogStat & LOG_PERROR) {
+		struct iovec iov[2];
+		struct iovec *v = iov;
+
+		v->iov_base = stdp;
+		v->iov_len = cnt - (stdp - tbuf);
+		++v;
+		v->iov_base = "\n";
+		v->iov_len = 1;
+		(void)_writev(STDERR_FILENO, iov, 2);
+	}
+
+	/* Get connected, output the message to the local logger. */
+	if (!opened)
+		openlog_unlocked(LogTag, LogStat | LOG_NDELAY, 0);
+	connectlog();
+
+	/*
+	 * If the send() failed, there are two likely scenarios: 
+	 *  1) syslogd was restarted
+	 *  2) /var/run/log is out of socket buffer space, which
+	 *     in most cases means local DoS.
+	 * We attempt to reconnect to /var/run/log to take care of
+	 * case #1 and keep send()ing data to cover case #2
+	 * to give syslogd a chance to empty its socket buffer.
+	 *
+	 * If we are working with a priveleged socket, then take
+	 * only one attempt, because we don't want to freeze a
+	 * critical application like su(1) or sshd(8).
+	 *
+	 */
+
+	if (send(LogFile, tbuf, cnt, 0) < 0) {
+		if (errno != ENOBUFS) {
+			disconnectlog();
+			connectlog();
+		}
+		do {
+			_usleep(1);
+			if (send(LogFile, tbuf, cnt, 0) >= 0) {
+				THREAD_UNLOCK();
+				return;
+			}
+			if (status == CONNPRIV)
+				break;
+		} while (errno == ENOBUFS);
+	} else {
+		THREAD_UNLOCK();
+		return;
+	}
+
+	/*
+	 * Output the message to the console; try not to block
+	 * as a blocking console should not stop other processes.
+	 * Make sure the error reported is the one from the syslogd failure.
+	 */
+	if (LogStat & LOG_CONS &&
+	    (fd = _open(_PATH_CONSOLE, O_WRONLY|O_NONBLOCK, 0)) >= 0) {
+		struct iovec iov[2];
+		struct iovec *v = iov;
+
+		p = strchr(tbuf, '>') + 1;
+		v->iov_base = p;
+		v->iov_len = cnt - (p - tbuf);
+		++v;
+		v->iov_base = "\r\n";
+		v->iov_len = 2;
+		(void)_writev(fd, iov, 2);
+		(void)_close(fd);
+	}
+
+	THREAD_UNLOCK();
+}
+
+/* Should be called with mutex acquired */
+static void
+disconnectlog(void)
+{
+	/*
+	 * If the user closed the FD and opened another in the same slot,
+	 * that's their problem.  They should close it before calling on
+	 * system services.
+	 */
+	if (LogFile != -1) {
+		_close(LogFile);
+		LogFile = -1;
+	}
+	status = NOCONN;			/* retry connect */
+}
+
+/* Should be called with mutex acquired */
+static void
+connectlog(void)
+{
+	struct sockaddr_un SyslogAddr;	/* AF_UNIX address of local logger */
+
+	if (LogFile == -1) {
+		if ((LogFile = _socket(AF_UNIX, SOCK_DGRAM, 0)) == -1)
+			return;
+		(void)_fcntl(LogFile, F_SETFD, 1);
+	}
+	if (LogFile != -1 && status == NOCONN) {
+		SyslogAddr.sun_len = sizeof(SyslogAddr);
+		SyslogAddr.sun_family = AF_UNIX;
+
+		/*
+		 * First try priveleged socket. If no success,
+		 * then try default socket.
+		 */
+		(void)strncpy(SyslogAddr.sun_path, _PATH_LOG_PRIV,
+		    sizeof SyslogAddr.sun_path);
+		if (_connect(LogFile, (struct sockaddr *)&SyslogAddr,
+		    sizeof(SyslogAddr)) != -1)
+			status = CONNPRIV;
+
+		if (status == NOCONN) {
+			(void)strncpy(SyslogAddr.sun_path, _PATH_LOG,
+			    sizeof SyslogAddr.sun_path);
+			if (_connect(LogFile, (struct sockaddr *)&SyslogAddr,
+			    sizeof(SyslogAddr)) != -1)
+				status = CONNDEF;
+		}
+
+		if (status == NOCONN) {
+			/*
+			 * Try the old "/dev/log" path, for backward
+			 * compatibility.
+			 */
+			(void)strncpy(SyslogAddr.sun_path, _PATH_OLDLOG,
+			    sizeof SyslogAddr.sun_path);
+			if (_connect(LogFile, (struct sockaddr *)&SyslogAddr,
+			    sizeof(SyslogAddr)) != -1)
+				status = CONNDEF;
+		}
+
+		if (status == NOCONN) {
+			(void)_close(LogFile);
+			LogFile = -1;
+		}
+	}
+}
+
+static void
+openlog_unlocked(const char *ident, int logstat, int logfac)
+{
+	if (ident != NULL)
+		LogTag = ident;
+	LogStat = logstat;
+	if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0)
+		LogFacility = logfac;
+
+	if (LogStat & LOG_NDELAY)	/* open immediately */
+		connectlog();
+
+	opened = 1;	/* ident and facility has been set */
+}
+
+void
+openlog(const char *ident, int logstat, int logfac)
+{
+	THREAD_LOCK();
+	openlog_unlocked(ident, logstat, logfac);
+	THREAD_UNLOCK();
+}
+
+
+void
+closelog(void)
+{
+	THREAD_LOCK();
+	(void)_close(LogFile);
+	LogFile = -1;
+	LogTag = NULL;
+	status = NOCONN;
+	THREAD_UNLOCK();
+}
+
+/* setlogmask -- set the log mask level */
+int
+setlogmask(int pmask)
+{
+	int omask;
+
+	THREAD_LOCK();
+	omask = LogMask;
+	if (pmask != 0)
+		LogMask = pmask;
+	THREAD_UNLOCK();
+	return (omask);
+}