finger.c

操作系统源代码

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)finger.c 1.1 87/12/21 SMI"; /* from 5.8 3/13/86 */
#endif /* not lint */

/*
 * This is a finger program.  It prints out useful information about users
 * by digging it up from various system files.
 *
 * There are three output formats, all of which give login name, teletype
 * line number, and login time.  The short output format is reminiscent
 * of finger on ITS, and gives one line of information per user containing
 * in addition to the minimum basic requirements (MBR), the full name of
 * the user, his idle time and location.  The
 * quick style output is UNIX who-like, giving only name, teletype and
 * login time.  Finally, the long style output give the same information
 * as the short (in more legible format), the home directory and shell
 * of the user, and, if it exits, a copy of the file .plan in the users
 * home directory.  Finger may be called with or without a list of people
 * to finger -- if no list is given, all the people currently logged in
 * are fingered.
 *
 * The program is validly called by one of the following:
 *
 *	finger			{short form list of users}
 *	finger -l		{long form list of users}
 *	finger -b		{briefer long form list of users}
 *	finger -q		{quick list of users}
 *	finger -i		{quick list of users with idle times}
 *	finger namelist		{long format list of specified users}
 *	finger -s namelist	{short format list of specified users}
 *	finger -w namelist	{narrow short format list of specified users}
 *
 * where 'namelist' is a list of users login names.
 * The other options can all be given after one '-', or each can have its
 * own '-'.  The -f option disables the printing of headers for short and
 * quick outputs.  The -b option briefens long format outputs.  The -p
 * option turns off plans for long format outputs.
 */

#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <utmp.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <net/gen/in.h>
#include <net/gen/inet.h>
#include <net/gen/netdb.h>
#include <net/gen/socket.h>
#include <net/gen/tcp.h>
#include <net/gen/tcp_hdr.h>
#include <net/gen/tcp_io.h>
#include <net/hton.h>
#include <net/netlib.h>

#define NONOTHING	1		/* don't say "No plan", or "No mail" */

#define NONET	0

#define ASTERISK	'*'		/* ignore this in real name */
#define COMMA		','		/* separator in pw_gecos field */
#define COMMAND		'-'		/* command line flag char */
#define SAMENAME	'&'		/* repeat login name in real name */
#define TALKABLE	0220		/* tty is writable if this mode */

struct utmp user;
#define NMAX sizeof(user.ut_name)
#define LMAX sizeof(user.ut_line)
#define HMAX sizeof(user.ut_host)

struct person {			/* one for each person fingered */
	char *name;			/* name */
	char tty[LMAX+1];		/* null terminated tty line */
	char host[HMAX+1];		/* null terminated remote host name */
	long loginat;			/* time of (last) login */
	long idletime;			/* how long idle (if logged in) */
	char *realname;			/* pointer to full name */
	struct passwd *pwd;		/* structure of /etc/passwd stuff */
	char loggedin;			/* person is logged in */
	char writable;			/* tty is writable */
	char original;			/* this is not a duplicate entry */
	struct person *link;		/* link to next person */
	char *where;			/* terminal location */
	char hostt[HMAX+1];		/* login host */
};

char LASTLOG[] = "/usr/adm/lastlog";	/* last login info */
char USERLOG[] = "/etc/utmp";		/* who is logged in */
char PLAN[] = "/.plan";			/* what plan file is */
char PROJ[] = "/.project";		/* what project file */
	
int unbrief = 1;			/* -b option default */
int header = 1;				/* -f option default */
int hack = 1;				/* -h option default */
int idle = 0;				/* -i option default */
int large = 0;				/* -l option default */
int match = 1;				/* -m option default */
int plan = 1;				/* -p option default */
int unquick = 1;			/* -q option default */
int small = 0;				/* -s option default */
int wide = 1;				/* -w option default */

int unshort;
int lf;					/* LASTLOG file descriptor */
struct person *person1;			/* list of people */
long tloc;				/* current time */

#if !_MINIX
char *strcpy();
char *ctime();
#endif

char *prog_name;

int main (int argc, char *argv[]);
static void doall(void);
static void donames(char **args);
static void print(void);
static void fwopen(void);
static void decode(struct person *pers);
static void fwclose(void);
static int netfinger (char *name);
static int matchcmp (char *gname, char *login, char *given);
static void quickprint (struct person *pers);
static void shortprint (struct person *pers);
static void personprint (struct person *pers);
static int AlreadyPrinted(int uid);
static int AnyMail (char *name);
static struct passwd *pwdcopy(struct passwd *pfrom);
static void findidle (struct person *pers);
static int ltimeprint (char *dt, long *before, char *after);
static void stimeprint (long *dt);
static void findwhen (struct person *pers);
static int namecmp (char *name1, char *name2);

main(argc, argv)
	int argc;
	register char **argv;
{
	FILE *fp;
	register char *s;

	prog_name= argv[0];

	/* parse command line for (optional) arguments */
	while (*++argv && **argv == COMMAND)
		for (s = *argv + 1; *s; s++)
			switch (*s) {
			case 'b':
				unbrief = 0;
				break;
			case 'f':
				header = 0;
				break;
			case 'h':
				hack = 0;
				break;
			case 'i':
				idle = 1;
				unquick = 0;
				break;
			case 'l':
				large = 1;
				break;
			case 'm':
				match = 0;
				break;
			case 'p':
				plan = 0;
				break;
			case 'q':
				unquick = 0;
				break;
			case 's':
				small = 1;
				break;
			case 'w':
				wide = 0;
				break;
			default:
				fprintf(stderr, "Usage: finger [-bfhilmpqsw] [login1 [login2 ...] ]\n");
				exit(1);
			}
	if (unquick || idle)
		time(&tloc);
	/*
	 * *argv == 0 means no names given
	 */
	if (*argv == 0)
		doall();
	else
		donames(argv);
	if (person1)
		print();
	exit(0);
}

static void doall()
{
	register struct person *p;
	register struct passwd *pw;
	int uf;
	char name[NMAX + 1];

	unshort = large;
	if ((uf = open(USERLOG, 0)) < 0) {
		fprintf(stderr, "finger: error opening %s\n", USERLOG);
		exit(2);
	}
	if (unquick) {
		setpwent();
		fwopen();
	}
	while (read(uf, (char *)&user, sizeof user) == sizeof user) {
		if (user.ut_name[0] == 0)
			continue;
		if (person1 == 0)
			p = person1 = (struct person *) malloc(sizeof *p);
		else {
			p->link = (struct person *) malloc(sizeof *p);
			p = p->link;
		}
		bcopy(user.ut_name, name, NMAX);
		name[NMAX] = 0;
		bcopy(user.ut_line, p->tty, LMAX);
		p->tty[LMAX] = 0;
		bcopy(user.ut_host, p->host, HMAX);
		p->host[HMAX] = 0;
		p->loginat = user.ut_time;
		p->pwd = 0;
		p->loggedin = 1;
		p->where = NULL;
		if (unquick && (pw = getpwnam(name))) {
			p->pwd = pwdcopy(pw);
			decode(p);
			p->name = p->pwd->pw_name;
		} else
			p->name = strcpy(malloc(strlen(name) + 1), name);
	}
	if (unquick) {
		fwclose();
		endpwent();
	}
	close(uf);
	if (person1 == 0) {
		printf("No one logged on\n");
		return;
	}
	p->link = 0;
}

static void donames(argv)
	char **argv;
{
	register struct person *p;
	register struct passwd *pw;
	int uf;

	/*
	 * get names from command line and check to see if they're
	 * logged in
	 */
	unshort = !small;
	for (; *argv != 0; argv++) {
		if (netfinger(*argv))
			continue;
		if (person1 == 0)
			p = person1 = (struct person *) malloc(sizeof *p);
		else {
			p->link = (struct person *) malloc(sizeof *p);
			p = p->link;
		}
		p->name = *argv;
		p->loggedin = 0;
		p->original = 1;
		p->pwd = 0;
	}
	if (person1 == 0)
		return;
	p->link = 0;
	/*
	 * if we are doing it, read /etc/passwd for the useful info
	 */
	if (unquick) {
		setpwent();
		if (!match) {
			for (p = person1; p != 0; p = p->link)
				if (pw = getpwnam(p->name))
					p->pwd = pwdcopy(pw);
		} else while ((pw = getpwent()) != 0) {
			for (p = person1; p != 0; p = p->link) {
				if (!p->original)
					continue;
				if (strcmp(p->name, pw->pw_name) != 0 &&
				    !matchcmp(pw->pw_gecos, pw->pw_name, p->name))
					continue;
				if (p->pwd == 0)
					p->pwd = pwdcopy(pw);
				else {
					struct person *new;
					/*
					 * handle multiple login names, insert
					 * new "duplicate" entry behind
					 */
					new = (struct person *)
						malloc(sizeof *new);
					new->pwd = pwdcopy(pw);
					new->name = p->name;
					new->original = 1;
					new->loggedin = 0;
					new->link = p->link;
					p->original = 0;
					p->link = new;
					p = new;
				}
			}
		}
		endpwent();
	}
	/* Now get login information */
	if ((uf = open(USERLOG, 0)) < 0) {
		fprintf(stderr, "finger: error opening %s\n", USERLOG);
		exit(2);
	}
	while (read(uf, (char *)&user, sizeof user) == sizeof user) {
		if (*user.ut_name == 0)
			continue;
		for (p = person1; p != 0; p = p->link) {
			if (p->loggedin == 2)
				continue;
			if (strncmp(p->pwd ? p->pwd->pw_name : p->name,
				    user.ut_name, NMAX) != 0)
				continue;
			if (p->loggedin == 0) {
				bcopy(user.ut_line, p->tty, LMAX);
				p->tty[LMAX] = 0;
				bcopy(user.ut_host, p->host, HMAX);
				p->host[HMAX] = 0;
				p->loginat = user.ut_time;
				p->loggedin = 1;
			} else {	/* p->loggedin == 1 */
				struct person *new;
				new = (struct person *) malloc(sizeof *new);
				new->name = p->name;
				bcopy(user.ut_line, new->tty, LMAX);
				new->tty[LMAX] = 0;
				bcopy(user.ut_host, new->host, HMAX);
				new->host[HMAX] = 0;
				new->loginat = user.ut_time;
				new->pwd = p->pwd;
				new->loggedin = 1;
				new->original = 0;
				new->link = p->link;
				p->loggedin = 2;
				p->link = new;
				p = new;
			}
		}
	}
	close(uf);
	if (unquick) {
		fwopen();
		for (p = person1; p != 0; p = p->link)
			decode(p);
		fwclose();
	}
}

static void print()
{
	register FILE *fp;
	register struct person *p;
	register char *s;
	register c;

	/*
	 * print out what we got
	 */
	if (header) {
		if (unquick) {
			if (!unshort)
				if (wide)
					printf("Login       Name              TTY Idle    When            Where\n");
				else
					printf("Login    TTY Idle    When            Where\n");
		} else {
			printf("Login      TTY            When");
			if (idle)
				printf("             Idle");
			putchar('\n');
		}
	}
	for (p = person1; p != 0; p = p->link) {
		if (!unquick) {
			quickprint(p);
			continue;
		}
		if (!unshort) {
			shortprint(p);
			continue;
		}
		personprint(p);
		if (p->pwd != 0 && !AlreadyPrinted(p->pwd->pw_uid)) {
			AnyMail(p->pwd->pw_name);
			if (hack) {
				s = malloc(strlen(p->pwd->pw_dir) +
					sizeof PROJ);
				strcpy(s, p->pwd->pw_dir);
				strcat(s, PROJ);
				if ((fp = fopen(s, "r")) != 0) {
					printf("Project: ");
					while ((c = getc(fp)) != EOF) {
						if (c == '\n')
							break;
						if (isprint(c) || isspace(c))
							putchar(c);
						else
							putchar(c ^ 100);
					}
					fclose(fp);
					putchar('\n');
				}
				free(s);
			}
			if (plan) {
				s = malloc(strlen(p->pwd->pw_dir) +
					sizeof PLAN);
				strcpy(s, p->pwd->pw_dir);
				strcat(s, PLAN);
				if ((fp = fopen(s, "r")) == 0) {
					if (!NONOTHING) printf("No Plan.\n");
				} else {
					printf("Plan:\n");
					while ((c = getc(fp)) != EOF)
						if (isprint(c) || isspace(c))
							putchar(c);
						else
							putchar(c ^ 100);
					fclose(fp);
				}
				free(s);
			}
		}
		if (p->link != 0)
			putchar('\n');
	}
}

/*
 * Duplicate a pwd entry.
 * Note: Only the useful things (what the program currently uses) are copied.
 */
static struct passwd *
pwdcopy(pfrom)
	register struct passwd *pfrom;
{
	register struct passwd *pto;

	pto = (struct passwd *) malloc(sizeof *pto);
#define savestr(s) strcpy(malloc(strlen(s) + 1), s)
	pto->pw_name = savestr(pfrom->pw_name);
	pto->pw_uid = pfrom->pw_uid;
	pto->pw_gecos = savestr(pfrom->pw_gecos);
	pto->pw_dir = savestr(pfrom->pw_dir);
	pto->pw_shell = savestr(pfrom->pw_shell);
#undef savestr
	return pto;
}

/*
 * print out information on quick format giving just name, tty, login time
 * and idle time if idle is set.
 */
static void quickprint(pers)
	register struct person *pers;
{
	printf("%-*.*s  ", NMAX, NMAX, pers->name);
	if (pers->loggedin) {
		if (idle) {
			findidle(pers);
			printf("%c%-*s %-16.16s", pers->writable ? ' ' : '*',
				LMAX, pers->tty, ctime(&pers->loginat));
			ltimeprint("   ", &pers->idletime, "");
		} else
			printf(" %-*s %-16.16s", LMAX,
				pers->tty, ctime(&pers->loginat));
		putchar('\n');
	} else
		printf("          Not Logged In\n");
}

/*
 * print out information in short format, giving login name, full name,
 * tty, idle time, login time, and host.
 */
static void shortprint(pers)
	register struct person *pers;
{
	char *p;
	char dialup;

	if (pers->pwd == 0) {
		printf("%-15s       ???\n", pers->name);
		return;
	}
	printf("%-*s", NMAX, pers->pwd->pw_name);
	dialup = 0;
	if (wide) {
		if (pers->realname)
			printf(" %-20.20s", pers->realname);
		else
			printf("        ???          ");
	}
	putchar(' ');
	if (pers->loggedin && !pers->writable)
		putchar('*');
	else
		putchar(' ');
	if (*pers->tty) {
		if (pers->tty[0] == 't' && pers->tty[1] == 't' &&
		    pers->tty[2] == 'y') {
			if (pers->tty[3] == 'd' && pers->loggedin)
				dialup = 1;
			printf("%-2.2s ", pers->tty + 3);
		} else
			printf("%-2.2s ", pers->tty);
	} else
		printf("   ");
	p = ctime(&pers->loginat);
	if (pers->loggedin) {
		stimeprint(&pers->idletime);
		printf(" %3.3s %-5.5s ", p, p + 11);
	} else if (pers->loginat == 0)