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/* vi: set sw=4 ts=4: */
/*
* issue.c: issue printing code
*
* Copyright (C) 2003 Bastian Blank <waldi@tuxbox.org>
*
* Optimize and correcting OCRNL by Vladimir Oleynik <dzo@simtreas.ru>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include <sys/param.h> /* MAXHOSTNAMELEN */
#include <sys/utsname.h>
#include "libbb.h"
#define LOGIN " login: "
static const char fmtstr_d[] ALIGN1 = "%A, %d %B %Y";
static const char fmtstr_t[] ALIGN1 = "%H:%M:%S";
void print_login_issue(const char *issue_file, const char *tty)
{
FILE *fd;
int c;
char buf[256+1];
const char *outbuf;
time_t t;
struct utsname uts;
time(&t);
uname(&uts);
puts("\r"); /* start a new line */
fd = fopen(issue_file, "r");
if (!fd)
return;
while ((c = fgetc(fd)) != EOF) {
outbuf = buf;
buf[0] = c;
buf[1] = '\0';
if (c == '\n') {
buf[1] = '\r';
buf[2] = '\0';
}
if (c == '\\' || c == '%') {
c = fgetc(fd);
switch (c) {
case 's':
outbuf = uts.sysname;
break;
case 'n':
case 'h':
outbuf = uts.nodename;
break;
case 'r':
outbuf = uts.release;
break;
case 'v':
outbuf = uts.version;
break;
case 'm':
outbuf = uts.machine;
break;
case 'D':
case 'o':
c = getdomainname(buf, sizeof(buf) - 1);
buf[c >= 0 ? c : 0] = '\0';
break;
case 'd':
strftime(buf, sizeof(buf), fmtstr_d, localtime(&t));
break;
case 't':
strftime(buf, sizeof(buf), fmtstr_t, localtime(&t));
break;
case 'l':
outbuf = tty;
break;
default:
buf[0] = c;
}
}
fputs(outbuf, stdout);
}
fclose(fd);
fflush(stdout);
}
void print_login_prompt(void)
{
char *hostname = safe_gethostname();
fputs(hostname, stdout);
fputs(LOGIN, stdout);
fflush(stdout);
free(hostname);
}
/* Clear dangerous stuff, set PATH */
static const char forbid[] ALIGN1 =
"ENV" "\0"
"BASH_ENV" "\0"
"HOME" "\0"
"IFS" "\0"
"SHELL" "\0"
"LD_LIBRARY_PATH" "\0"
"LD_PRELOAD" "\0"
"LD_TRACE_LOADED_OBJECTS" "\0"
"LD_BIND_NOW" "\0"
"LD_AOUT_LIBRARY_PATH" "\0"
"LD_AOUT_PRELOAD" "\0"
"LD_NOWARN" "\0"
"LD_KEEPDIR" "\0";
int sanitize_env_if_suid(void)
{
const char *p;
if (getuid() == geteuid())
return 0;
p = forbid;
do {
unsetenv(p);
p += strlen(p) + 1;
} while (*p);
putenv((char*)bb_PATH_root_path);
return 1; /* we indeed were run by different user! */
}
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