freebsd-skq/usr.sbin/newsyslog/newsyslog.c

/*
 * This file contains changes from the Open Software Foundation.
 */

/*

Copyright 1988, 1989 by the Massachusetts Institute of Technology

Permission to use, copy, modify, and distribute this software
and its documentation for any purpose and without fee is
hereby granted, provided that the above copyright notice
appear in all copies and that both that copyright notice and
this permission notice appear in supporting documentation,
and that the names of M.I.T. and the M.I.T. S.I.P.B. not be
used in advertising or publicity pertaining to distribution
of the software without specific, written prior permission.
M.I.T. and the M.I.T. S.I.P.B. make no representations about
the suitability of this software for any purpose.  It is
provided "as is" without express or implied warranty.

*/

/*
 *      newsyslog - roll over selected logs at the appropriate time,
 *              keeping the a specified number of backup files around.
 */

#ifndef lint
static const char rcsid[] =
"$FreeBSD$";

#endif				/* not lint */

#define OSF
#ifndef COMPRESS_POSTFIX
#define COMPRESS_POSTFIX ".gz"
#endif

#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <grp.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <sys/wait.h>

#include "pathnames.h"

#define kbytes(size)  (((size) + 1023) >> 10)
#ifdef _IBMR2
/* Calculates (db * DEV_BSIZE) */
#define dbtob(db)  ((unsigned)(db) << UBSHIFT)
#endif

#define CE_COMPACT 1		/* Compact the achived log files */
#define CE_BINARY  2		/* Logfile is in binary, don't add */
 /* status messages */
#define	CE_TRIMAT  4		/* trim at a specific time */

#define NONE -1

struct conf_entry {
	char *log;		/* Name of the log */
	char *pid_file;		/* PID file */
	int uid;		/* Owner of log */
	int gid;		/* Group of log */
	int numlogs;		/* Number of logs to keep */
	int size;		/* Size cutoff to trigger trimming the log */
	int hours;		/* Hours between log trimming */
	time_t trim_at;		/* Specific time to do trimming */
	int permissions;	/* File permissions on the log */
	int flags;		/* Flags (CE_COMPACT & CE_BINARY)  */
	int sig;		/* Signal to send */
	struct conf_entry *next;/* Linked list pointer */
};

int verbose = 0;		/* Print out what's going on */
int needroot = 1;		/* Root privs are necessary */
int noaction = 0;		/* Don't do anything, just show it */
int force = 0;			/* Force the trim no matter what */
char *conf = _PATH_CONF;	/* Configuration file to use */
time_t timenow;

#define MIN_PID         5
#define MAX_PID		99999	/* was lower, see /usr/include/sys/proc.h */
char hostname[MAXHOSTNAMELEN + 1];	/* hostname */
char *daytime;			/* timenow in human readable form */

static struct conf_entry *parse_file();
static char *sob(char *p);
static char *son(char *p);
static char *missing_field(char *p, char *errline);
static void do_entry(struct conf_entry * ent);
static void PRS(int argc, char **argv);
static void usage();
static void dotrim(char *log, char *pid_file, int numdays, int falgs, int perm, int owner_uid, int group_gid, int sig);
static int log_trim(char *log);
static void compress_log(char *log);
static int sizefile(char *file);
static int age_old_log(char *file);
static pid_t get_pid(char *pid_file);
static time_t parse8601(const char *s);

int 
main(argc, argv)
	int argc;
	char **argv;
{
	struct conf_entry *p, *q;

	PRS(argc, argv);
	if (needroot && getuid() && geteuid())
		errx(1, "must have root privs");
	p = q = parse_file();

	while (p) {
		do_entry(p);
		p = p->next;
		free((char *) q);
		q = p;
	}
	return (0);
}

static void 
do_entry(ent)
	struct conf_entry *ent;

{
	int size, modtime;
	char *pid_file;

	if (verbose) {
		if (ent->flags & CE_COMPACT)
			printf("%s <%dZ>: ", ent->log, ent->numlogs);
		else
			printf("%s <%d>: ", ent->log, ent->numlogs);
	}
	size = sizefile(ent->log);
	modtime = age_old_log(ent->log);
	if (size < 0) {
		if (verbose)
			printf("does not exist.\n");
	} else {
		if (ent->flags & CE_TRIMAT) {
			if (timenow < ent->trim_at
			    || difftime(timenow, ent->trim_at) >= 60 * 60) {
				if (verbose)
					printf("--> will trim at %s",
					    ctime(&ent->trim_at));
				return;
			} else if (verbose && ent->hours <= 0) {
				printf("--> time is up\n");
			}
		}
		if (verbose && (ent->size > 0))
			printf("size (Kb): %d [%d] ", size, ent->size);
		if (verbose && (ent->hours > 0))
			printf(" age (hr): %d [%d] ", modtime, ent->hours);
		if (force || ((ent->size > 0) && (size >= ent->size)) ||
		    (ent->hours <= 0 && (ent->flags & CE_TRIMAT)) ||
		    ((ent->hours > 0) && ((modtime >= ent->hours)
			    || (modtime < 0)))) {
			if (verbose)
				printf("--> trimming log....\n");
			if (noaction && !verbose) {
				if (ent->flags & CE_COMPACT)
					printf("%s <%dZ>: trimming\n",
					    ent->log, ent->numlogs);
				else
					printf("%s <%d>: trimming\n",
					    ent->log, ent->numlogs);
			}
			if (ent->pid_file) {
				pid_file = ent->pid_file;
			} else {
				/* Only try to notify syslog if we are root */
				if (needroot)
					pid_file = _PATH_SYSLOGPID;
				else
					pid_file = NULL;
			}
			dotrim(ent->log, pid_file, ent->numlogs,
			    ent->flags, ent->permissions, ent->uid, ent->gid, ent->sig);
		} else {
			if (verbose)
				printf("--> skipping\n");
		}
	}
}

static void 
PRS(argc, argv)
	int argc;
	char **argv;
{
	int c;
	char *p;

	timenow = time((time_t *) 0);
	daytime = ctime(&timenow) + 4;
	daytime[15] = '\0';

	/* Let's get our hostname */
	(void) gethostname(hostname, sizeof(hostname));

	/* Truncate domain */
	if ((p = strchr(hostname, '.'))) {
		*p = '\0';
	}
	optind = 1;		/* Start options parsing */
	while ((c = getopt(argc, argv, "nrvFf:t:")) != -1)
		switch (c) {
		case 'n':
			noaction++;
			break;
		case 'r':
			needroot = 0;
			break;
		case 'v':
			verbose++;
			break;
		case 'f':
			conf = optarg;
			break;
		case 'F':
			force++;
			break;
		default:
			usage();
		}
}

static void 
usage()
{
	fprintf(stderr, "usage: newsyslog [-Fnrv] [-f config-file]\n");
	exit(1);
}

/* Parse a configuration file and return a linked list of all the logs
 * to process
 */
static struct conf_entry *
parse_file()
{
	FILE *f;
	char line[BUFSIZ], *parse, *q;
	char *errline, *group;
	struct conf_entry *first = NULL;
	struct conf_entry *working = NULL;
	struct passwd *pass;
	struct group *grp;
	int eol;

	if (strcmp(conf, "-"))
		f = fopen(conf, "r");
	else
		f = stdin;
	if (!f)
		err(1, "%s", conf);
	while (fgets(line, BUFSIZ, f)) {
		if ((line[0] == '\n') || (line[0] == '#'))
			continue;
		errline = strdup(line);
		if (!first) {
			working = (struct conf_entry *) malloc(sizeof(struct conf_entry));
			first = working;
		} else {
			working->next = (struct conf_entry *) malloc(sizeof(struct conf_entry));
			working = working->next;
		}

		q = parse = missing_field(sob(line), errline);
		parse = son(line);
		if (!*parse)
			errx(1, "malformed line (missing fields):\n%s", errline);
		*parse = '\0';
		working->log = strdup(q);

		q = parse = missing_field(sob(++parse), errline);
		parse = son(parse);
		if (!*parse)
			errx(1, "malformed line (missing fields):\n%s", errline);
		*parse = '\0';
		if ((group = strchr(q, ':')) != NULL ||
		    (group = strrchr(q, '.')) != NULL) {
			*group++ = '\0';
			if (*q) {
				if (!(isnumber(*q))) {
					if ((pass = getpwnam(q)) == NULL)
						errx(1,
						    "error in config file; unknown user:\n%s",
						    errline);
					working->uid = pass->pw_uid;
				} else
					working->uid = atoi(q);
			} else
				working->uid = NONE;

			q = group;
			if (*q) {
				if (!(isnumber(*q))) {
					if ((grp = getgrnam(q)) == NULL)
						errx(1,
						    "error in config file; unknown group:\n%s",
						    errline);
					working->gid = grp->gr_gid;
				} else
					working->gid = atoi(q);
			} else
				working->gid = NONE;

			q = parse = missing_field(sob(++parse), errline);
			parse = son(parse);
			if (!*parse)
				errx(1, "malformed line (missing fields):\n%s", errline);
			*parse = '\0';
		} else
			working->uid = working->gid = NONE;

		if (!sscanf(q, "%o", &working->permissions))
			errx(1, "error in config file; bad permissions:\n%s",
			    errline);

		q = parse = missing_field(sob(++parse), errline);
		parse = son(parse);
		if (!*parse)
			errx(1, "malformed line (missing fields):\n%s", errline);
		*parse = '\0';
		if (!sscanf(q, "%d", &working->numlogs))
			errx(1, "error in config file; bad number:\n%s",
			    errline);

		q = parse = missing_field(sob(++parse), errline);
		parse = son(parse);
		if (!*parse)
			errx(1, "malformed line (missing fields):\n%s", errline);
		*parse = '\0';
		if (isdigit(*q))
			working->size = atoi(q);
		else
			working->size = -1;

		working->flags = 0;
		q = parse = missing_field(sob(++parse), errline);
		parse = son(parse);
		eol = !*parse;
		*parse = '\0';
		{
			char *ep;
			u_long ul;

			ul = strtoul(q, &ep, 10);
			if (ep == q)
				working->hours = 0;
			else if (*ep == '*')
				working->hours = -1;
			else if (ul > INT_MAX)
				errx(1, "interval is too large:\n%s", errline);
			else
				working->hours = ul;

			if (*ep != '\0' && *ep != '@' && *ep != '*')
				errx(1, "malformed interval/at:\n%s", errline);
			if (*ep == '@') {
				if ((working->trim_at = parse8601(ep + 1))
				    == (time_t) - 1)
					errx(1, "malformed at:\n%s", errline);
				working->flags |= CE_TRIMAT;
			}
		}

		if (eol)
			q = NULL;
		else {
			q = parse = sob(++parse);	/* Optional field */
			parse = son(parse);
			if (!*parse)
				eol = 1;
			*parse = '\0';
		}

		while (q && *q && !isspace(*q)) {
			if ((*q == 'Z') || (*q == 'z'))
				working->flags |= CE_COMPACT;
			else if ((*q == 'B') || (*q == 'b'))
				working->flags |= CE_BINARY;
			else if (*q != '-')
				errx(1, "illegal flag in config file -- %c", *q);
			q++;
		}

		if (eol)
			q = NULL;
		else {
			q = parse = sob(++parse);	/* Optional field */
			parse = son(parse);
			if (!*parse)
				eol = 1;
			*parse = '\0';
		}

		working->pid_file = NULL;
		if (q && *q) {
			if (*q == '/')
				working->pid_file = strdup(q);
			else if (isdigit(*q))
				goto got_sig;
			else
				errx(1, "illegal pid file or signal number in config file:\n%s", errline);
		}
		if (eol)
			q = NULL;
		else {
			q = parse = sob(++parse);	/* Optional field */
			*(parse = son(parse)) = '\0';
		}

		working->sig = SIGHUP;
		if (q && *q) {
			if (isdigit(*q)) {
		got_sig:
				working->sig = atoi(q);
			} else {
		err_sig:
				errx(1, "illegal signal number in config file:\n%s", errline);
			}
			if (working->sig < 1 || working->sig >= NSIG)
				goto err_sig;
		}
		free(errline);
	}
	if (working)
		working->next = (struct conf_entry *) NULL;
	(void) fclose(f);
	return (first);
}

static char *
missing_field(p, errline)
	char *p, *errline;
{
	if (!p || !*p)
		errx(1, "missing field in config file:\n%s", errline);
	return (p);
}

static void 
dotrim(log, pid_file, numdays, flags, perm, owner_uid, group_gid, sig)
	char *log;
	char *pid_file;
	int numdays;
	int flags;
	int perm;
	int owner_uid;
	int group_gid;
	int sig;
{
	char file1[MAXPATHLEN + 1], file2[MAXPATHLEN + 1];
	char zfile1[MAXPATHLEN + 1], zfile2[MAXPATHLEN + 1];
	int notified, need_notification, fd, _numdays;
	struct stat st;
	pid_t pid;

#ifdef _IBMR2
/* AIX 3.1 has a broken fchown- if the owner_uid is -1, it will actually */
/* change it to be owned by uid -1, instead of leaving it as is, as it is */
/* supposed to. */
	if (owner_uid == -1)
		owner_uid = geteuid();
#endif

	/* Remove oldest log */
	(void) sprintf(file1, "%s.%d", log, numdays);
	(void) strcpy(zfile1, file1);
	(void) strcat(zfile1, COMPRESS_POSTFIX);

	if (noaction) {
		printf("rm -f %s\n", file1);
		printf("rm -f %s\n", zfile1);
	} else {
		(void) unlink(file1);
		(void) unlink(zfile1);
	}

	/* Move down log files */
	_numdays = numdays;	/* preserve */
	while (numdays--) {
		(void) strcpy(file2, file1);
		(void) sprintf(file1, "%s.%d", log, numdays);
		(void) strcpy(zfile1, file1);
		(void) strcpy(zfile2, file2);
		if (lstat(file1, &st)) {
			(void) strcat(zfile1, COMPRESS_POSTFIX);
			(void) strcat(zfile2, COMPRESS_POSTFIX);
			if (lstat(zfile1, &st))
				continue;
		}
		if (noaction) {
			printf("mv %s %s\n", zfile1, zfile2);
			printf("chmod %o %s\n", perm, zfile2);
			printf("chown %d.%d %s\n",
			    owner_uid, group_gid, zfile2);
		} else {
			(void) rename(zfile1, zfile2);
			(void) chmod(zfile2, perm);
			(void) chown(zfile2, owner_uid, group_gid);
		}
	}
	if (!noaction && !(flags & CE_BINARY))
		(void) log_trim(log);	/* Report the trimming to the old log */

	if (!_numdays) {
		if (noaction)
			printf("rm %s\n", log);
		else
			(void) unlink(log);
	} else {
		if (noaction)
			printf("mv %s to %s\n", log, file1);
		else
			(void) rename(log, file1);
	}

	if (noaction)
		printf("Start new log...");
	else {
		fd = creat(log, perm);
		if (fd < 0)
			err(1, "can't start new log");
		if (fchown(fd, owner_uid, group_gid))
			err(1, "can't chmod new log file");
		(void) close(fd);
		if (!(flags & CE_BINARY))
			if (log_trim(log))	/* Add status message */
				err(1, "can't add status message to log");
	}
	if (noaction)
		printf("chmod %o %s...\n", perm, log);
	else
		(void) chmod(log, perm);

	pid = 0;
	need_notification = notified = 0;
	if (pid_file != NULL) {
		need_notification = 1;
		pid = get_pid(pid_file);
	}
	if (pid) {
		if (noaction) {
			notified = 1;
			printf("kill -%d %d\n", sig, (int) pid);
		} else if (kill(pid, sig))
			warn("can't notify daemon, pid %d", (int) pid);
		else {
			notified = 1;
			if (verbose)
				printf("daemon pid %d notified\n", (int) pid);
		}
	}
	if ((flags & CE_COMPACT)) {
		if (need_notification && !notified)
			warnx("log not compressed because daemon not notified");
		else if (noaction)
			printf("Compress %s.0\n", log);
		else {
			if (notified) {
				if (verbose)
					printf("small pause to allow daemon to close log\n");
				sleep(10);
			}
			compress_log(log);
		}
	}
}

/* Log the fact that the logs were turned over */
static int 
log_trim(log)
	char *log;
{
	FILE *f;

	if ((f = fopen(log, "a")) == NULL)
		return (-1);
	fprintf(f, "%s %s newsyslog[%d]: logfile turned over\n",
	    daytime, hostname, (int) getpid());
	if (fclose(f) == EOF)
		err(1, "log_trim: fclose:");
	return (0);
}

/* Fork of /usr/ucb/compress to compress the old log file */
static void 
compress_log(log)
	char *log;
{
	pid_t pid;
	char tmp[MAXPATHLEN + 1];

	(void) sprintf(tmp, "%s.0", log);
	pid = fork();
	if (pid < 0)
		err(1, "fork");
	else if (!pid) {
		(void) execl(_PATH_GZIP, _PATH_GZIP, "-f", tmp, 0);
		err(1, _PATH_GZIP);
	}
}

/* Return size in kilobytes of a file */
static int 
sizefile(file)
	char *file;
{
	struct stat sb;

	if (stat(file, &sb) < 0)
		return (-1);
	return (kbytes(dbtob(sb.st_blocks)));
}

/* Return the age of old log file (file.0) */
static int 
age_old_log(file)
	char *file;
{
	struct stat sb;
	char tmp[MAXPATHLEN + sizeof(".0") + sizeof(COMPRESS_POSTFIX) + 1];

	(void) strcpy(tmp, file);
	if (stat(strcat(tmp, ".0"), &sb) < 0)
		if (stat(strcat(tmp, COMPRESS_POSTFIX), &sb) < 0)
			return (-1);
	return ((int) (timenow - sb.st_mtime + 1800) / 3600);
}

static pid_t 
get_pid(pid_file)
	char *pid_file;
{
	FILE *f;
	char line[BUFSIZ];
	pid_t pid = 0;

	if ((f = fopen(pid_file, "r")) == NULL)
		warn("can't open %s pid file to restart a daemon",
		    pid_file);
	else {
		if (fgets(line, BUFSIZ, f)) {
			pid = atol(line);
			if (pid < MIN_PID || pid > MAX_PID) {
				warnx("preposterous process number: %d", (int) pid);
				pid = 0;
			}
		} else
			warn("can't read %s pid file to restart a daemon",
			    pid_file);
		(void) fclose(f);
	}
	return pid;
}

/* Skip Over Blanks */
char *
sob(p)
	register char *p;
{
	while (p && *p && isspace(*p))
		p++;
	return (p);
}

/* Skip Over Non-Blanks */
char *
son(p)
	register char *p;
{
	while (p && *p && !isspace(*p))
		p++;
	return (p);
}

/*
 * Parse a limited subset of ISO 8601.
 * The specific format is as follows:
 *
 *	[CC[YY[MM[DD]]]][THH[MM[SS]]]	(where `T' is the literal letter)
 *
 * We don't accept a timezone specification; missing fields (including
 * timezone) are defaulted to the current date but time zero.
 */
static time_t
parse8601(const char *s)
{
	char *t;
	struct tm tm, *tmp;
	u_long ul;

	tmp = localtime(&timenow);
	tm = *tmp;

	tm.tm_hour = tm.tm_min = tm.tm_sec = 0;

	ul = strtoul(s, &t, 10);
	if (*t != '\0' && *t != 'T')
		return -1;

	/*
	 * Now t points either to the end of the string (if no time was
	 * provided) or to the letter `T' which separates date and time in
	 * ISO 8601.  The pointer arithmetic is the same for either case.
	 */
	switch (t - s) {
	case 8:
		tm.tm_year = ((ul / 1000000) - 19) * 100;
		ul = ul % 1000000;
	case 6:
		tm.tm_year = tm.tm_year - (tm.tm_year % 100);
		tm.tm_year += ul / 10000;
		ul = ul % 10000;
	case 4:
		tm.tm_mon = (ul / 100) - 1;
		ul = ul % 100;
	case 2:
		tm.tm_mday = ul;
	case 0:
		break;
	default:
		return -1;
	}

	/* sanity check */
	if (tm.tm_year < 70 || tm.tm_mon < 0 || tm.tm_mon > 12
	    || tm.tm_mday < 1 || tm.tm_mday > 31)
		return -1;

	if (*t != '\0') {
		s = ++t;
		ul = strtoul(s, &t, 10);
		if (*t != '\0' && !isspace(*t))
			return -1;

		switch (t - s) {
		case 6:
			tm.tm_sec = ul % 100;
			ul /= 100;
		case 4:
			tm.tm_min = ul % 100;
			ul /= 100;
		case 2:
			tm.tm_hour = ul;
		case 0:
			break;
		default:
			return -1;
		}

		/* sanity check */
		if (tm.tm_sec < 0 || tm.tm_sec > 60 || tm.tm_min < 0
		    || tm.tm_min > 59 || tm.tm_hour < 0 || tm.tm_hour > 23)
			return -1;
	}
	return mktime(&tm);
}