diff options
Diffstat (limited to 'usr.bin/who/utmpentry.c')
-rw-r--r-- | usr.bin/who/utmpentry.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/usr.bin/who/utmpentry.c b/usr.bin/who/utmpentry.c new file mode 100644 index 0000000..c74397b --- /dev/null +++ b/usr.bin/who/utmpentry.c @@ -0,0 +1,329 @@ +/* $NetBSD: utmpentry.c,v 1.18 2015/11/21 15:01:43 christos Exp $ */ + +/*- + * Copyright (c) 2002 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Christos Zoulas. + * + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. + */ + +#include <sys/cdefs.h> +#ifndef lint +__RCSID("$NetBSD: utmpentry.c,v 1.18 2015/11/21 15:01:43 christos Exp $"); +#endif + +#include <sys/stat.h> + +#include <time.h> +#include <string.h> +#include <err.h> +#include <stdlib.h> + +#ifdef SUPPORT_UTMP +#include <utmp.h> +#endif +#ifdef SUPPORT_UTMPX +#include <utmpx.h> +#endif + +#include "utmpentry.h" + + +/* Fail the compile if x is not true, by constructing an illegal type. */ +#define COMPILE_ASSERT(x) /*LINTED null effect */ \ + ((void)sizeof(struct { unsigned : ((x) ? 1 : -1); })) + + +#ifdef SUPPORT_UTMP +static void getentry(struct utmpentry *, struct utmp *); +static struct timespec utmptime = {0, 0}; +#endif +#ifdef SUPPORT_UTMPX +static void getentryx(struct utmpentry *, struct utmpx *); +static struct timespec utmpxtime = {0, 0}; +#endif +#if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP) +static int setup(const char *); +static void adjust_size(struct utmpentry *e); +#endif + +size_t maxname = 8, maxline = 8, maxhost = 16; +int etype = 1 << USER_PROCESS; +static size_t numutmp = 0; +static struct utmpentry *ehead; + +#if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP) +static void +adjust_size(struct utmpentry *e) +{ + size_t max; + + if ((max = strlen(e->name)) > maxname) + maxname = max; + if ((max = strlen(e->line)) > maxline) + maxline = max; + if ((max = strlen(e->host)) > maxhost) + maxhost = max; +} + +static int +setup(const char *fname) +{ + int what = 3; + struct stat st; + const char *sfname; + + if (fname == NULL) { +#ifdef SUPPORT_UTMPX + setutxent(); +#endif +#ifdef SUPPORT_UTMP + setutent(); +#endif + } else { + size_t len = strlen(fname); + if (len == 0) + errx(1, "Filename cannot be 0 length."); + what = fname[len - 1] == 'x' ? 1 : 2; + if (what == 1) { +#ifdef SUPPORT_UTMPX + if (utmpxname(fname) == 0) + warnx("Cannot set utmpx file to `%s'", + fname); +#else + warnx("utmpx support not compiled in"); +#endif + } else { +#ifdef SUPPORT_UTMP + if (utmpname(fname) == 0) + warnx("Cannot set utmp file to `%s'", + fname); +#else + warnx("utmp support not compiled in"); +#endif + } + } +#ifdef SUPPORT_UTMPX + if (what & 1) { + sfname = fname ? fname : _PATH_UTMPX; + if (stat(sfname, &st) == -1) { + warn("Cannot stat `%s'", sfname); + what &= ~1; + } else { + if (timespeccmp(&st.st_mtimespec, &utmpxtime, >)) + utmpxtime = st.st_mtimespec; + else + what &= ~1; + } + } +#endif +#ifdef SUPPORT_UTMP + if (what & 2) { + sfname = fname ? fname : _PATH_UTMP; + if (stat(sfname, &st) == -1) { + warn("Cannot stat `%s'", sfname); + what &= ~2; + } else { + if (timespeccmp(&st.st_mtimespec, &utmptime, >)) + utmptime = st.st_mtimespec; + else + what &= ~2; + } + } +#endif + return what; +} +#endif + +void +endutentries(void) +{ + struct utmpentry *ep; + +#ifdef SUPPORT_UTMP + timespecclear(&utmptime); +#endif +#ifdef SUPPORT_UTMPX + timespecclear(&utmpxtime); +#endif + ep = ehead; + while (ep) { + struct utmpentry *sep = ep; + ep = ep->next; + free(sep); + } + ehead = NULL; + numutmp = 0; +} + +size_t +getutentries(const char *fname, struct utmpentry **epp) +{ +#ifdef SUPPORT_UTMPX + struct utmpx *utx; +#endif +#ifdef SUPPORT_UTMP + struct utmp *ut; +#endif +#if defined(SUPPORT_UTMP) || defined(SUPPORT_UTMPX) + struct utmpentry *ep; + int what = setup(fname); + struct utmpentry **nextp = &ehead; + switch (what) { + case 0: + /* No updates */ + *epp = ehead; + return numutmp; + default: + /* Need to re-scan */ + ehead = NULL; + numutmp = 0; + } +#endif + +#ifdef SUPPORT_UTMPX + while ((what & 1) && (utx = getutxent()) != NULL) { + if (fname == NULL && ((1 << utx->ut_type) & etype) == 0) + continue; + if ((ep = calloc(1, sizeof(struct utmpentry))) == NULL) { + warn(NULL); + return 0; + } + getentryx(ep, utx); + *nextp = ep; + nextp = &(ep->next); + } +#endif + +#ifdef SUPPORT_UTMP + if ((etype & (1 << USER_PROCESS)) != 0) { + while ((what & 2) && (ut = getutent()) != NULL) { + if (fname == NULL && (*ut->ut_name == '\0' || + *ut->ut_line == '\0')) + continue; + /* Don't process entries that we have utmpx for */ + for (ep = ehead; ep != NULL; ep = ep->next) { + if (strncmp(ep->line, ut->ut_line, + sizeof(ut->ut_line)) == 0) + break; + } + if (ep != NULL) + continue; + if ((ep = calloc(1, sizeof(*ep))) == NULL) { + warn(NULL); + return 0; + } + getentry(ep, ut); + *nextp = ep; + nextp = &(ep->next); + } + } +#endif + numutmp = 0; +#if defined(SUPPORT_UTMP) || defined(SUPPORT_UTMPX) + if (ehead != NULL) { + struct utmpentry *from = ehead, *save; + + ehead = NULL; + while (from != NULL) { + for (nextp = &ehead; + (*nextp) && strcmp(from->line, (*nextp)->line) > 0; + nextp = &(*nextp)->next) + continue; + save = from; + from = from->next; + save->next = *nextp; + *nextp = save; + numutmp++; + } + } + *epp = ehead; + return numutmp; +#else + *epp = NULL; + return 0; +#endif +} + +#ifdef SUPPORT_UTMP +static void +getentry(struct utmpentry *e, struct utmp *up) +{ + COMPILE_ASSERT(sizeof(e->name) > sizeof(up->ut_name)); + COMPILE_ASSERT(sizeof(e->line) > sizeof(up->ut_line)); + COMPILE_ASSERT(sizeof(e->host) > sizeof(up->ut_host)); + + /* + * e has just been calloc'd. We don't need to clear it or + * append null-terminators, because its length is strictly + * greater than the source string. Use strncpy to _read_ + * up->ut_* because they may not be terminated. For this + * reason we use the size of the _source_ as the length + * argument. + */ + (void)strncpy(e->name, up->ut_name, sizeof(up->ut_name)); + (void)strncpy(e->line, up->ut_line, sizeof(up->ut_line)); + (void)strncpy(e->host, up->ut_host, sizeof(up->ut_host)); + + e->tv.tv_sec = up->ut_time; + e->tv.tv_usec = 0; + e->pid = 0; + e->term = 0; + e->exit = 0; + e->sess = 0; + e->type = USER_PROCESS; + adjust_size(e); +} +#endif + +#ifdef SUPPORT_UTMPX +static void +getentryx(struct utmpentry *e, struct utmpx *up) +{ + COMPILE_ASSERT(sizeof(e->name) > sizeof(up->ut_name)); + COMPILE_ASSERT(sizeof(e->line) > sizeof(up->ut_line)); + COMPILE_ASSERT(sizeof(e->host) > sizeof(up->ut_host)); + + /* + * e has just been calloc'd. We don't need to clear it or + * append null-terminators, because its length is strictly + * greater than the source string. Use strncpy to _read_ + * up->ut_* because they may not be terminated. For this + * reason we use the size of the _source_ as the length + * argument. + */ + (void)strncpy(e->name, up->ut_name, sizeof(up->ut_name)); + (void)strncpy(e->line, up->ut_line, sizeof(up->ut_line)); + (void)strncpy(e->host, up->ut_host, sizeof(up->ut_host)); + + e->tv = up->ut_tv; + e->pid = up->ut_pid; + e->term = up->ut_exit.e_termination; + e->exit = up->ut_exit.e_exit; + e->sess = up->ut_session; + e->type = up->ut_type; + adjust_size(e); +} +#endif |