404 lines
8.6 KiB
C
404 lines
8.6 KiB
C
/*
|
|
** $NetBSD: parse.c,v 1.7 1996/08/30 17:41:38 thorpej Exp $
|
|
**
|
|
** parse.c This file contains the protocol parser
|
|
**
|
|
** This program is in the public domain and may be used freely by anyone
|
|
** who wants to.
|
|
**
|
|
** Last update: 6 Dec 1992
|
|
**
|
|
** Please send bug fixes/bug reports to: Peter Eriksson <pen@lysator.liu.se>
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
#include <ctype.h>
|
|
#include <pwd.h>
|
|
|
|
#include <sys/types.h>
|
|
#include <netinet/in.h>
|
|
|
|
#ifndef HPUX7
|
|
# include <arpa/inet.h>
|
|
#endif
|
|
|
|
#include <nlist.h>
|
|
#include <kvm.h>
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
|
|
#if defined(MIPS) || defined(BSD43)
|
|
extern int errno;
|
|
#endif
|
|
|
|
#include "identd.h"
|
|
#include "error.h"
|
|
|
|
extern void *malloc();
|
|
|
|
/*
|
|
** This function will eat whitespace characters until
|
|
** either a non-whitespace character is read, or EOF
|
|
** occurs. This function is only used if the "-m" option
|
|
** is enabled.
|
|
*/
|
|
static int eat_whitespace()
|
|
{
|
|
int c;
|
|
|
|
|
|
while ((c = getchar()) != EOF &&
|
|
!(c == '\r' || c == '\n'))
|
|
;
|
|
|
|
if (c != EOF)
|
|
while ((c = getchar()) != EOF &&
|
|
(c == ' ' || c == '\t' || c == '\n' || c == '\r'))
|
|
;
|
|
|
|
if (c != EOF)
|
|
ungetc(c, stdin);
|
|
|
|
return (c != EOF);
|
|
}
|
|
|
|
|
|
#ifdef INCLUDE_EXTENSIONS
|
|
/*
|
|
** Validate an indirect request
|
|
*/
|
|
static int valid_fhost(faddr, password)
|
|
struct in_addr *faddr;
|
|
char *password;
|
|
{
|
|
if (indirect_host == NULL)
|
|
return 0;
|
|
|
|
if (strcmp(indirect_host, "*") != 0)
|
|
{
|
|
if (isdigit(indirect_host[0]))
|
|
{
|
|
if (strcmp(inet_ntoa(*faddr), indirect_host))
|
|
{
|
|
syslog(LOG_NOTICE, "valid_fhost: access denied for: %s",
|
|
gethost(faddr));
|
|
return 0;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (strcmp(gethost(faddr), indirect_host))
|
|
{
|
|
syslog(LOG_NOTICE, "valid_fhost: access denied for: %s",
|
|
gethost(faddr));
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (indirect_password == NULL)
|
|
return 1;
|
|
|
|
if (strcmp(password, indirect_password))
|
|
{
|
|
syslog(LOG_NOTICE, "valid_fhost: invalid password from: %s",
|
|
gethost(faddr));
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
** A small routine to check for the existance of the ".noident"
|
|
** file in a users home directory.
|
|
*/
|
|
static int check_noident(homedir)
|
|
char *homedir;
|
|
{
|
|
char *tmp_path;
|
|
struct stat sbuf;
|
|
int rcode;
|
|
|
|
|
|
if (!homedir)
|
|
return 0;
|
|
|
|
tmp_path = (char *) malloc(strlen(homedir) + sizeof("/.noident") + 1);
|
|
if (!tmp_path)
|
|
return 0;
|
|
|
|
strcpy(tmp_path, homedir);
|
|
strcat(tmp_path, "/.noident");
|
|
|
|
rcode = stat(tmp_path, &sbuf);
|
|
free(tmp_path);
|
|
|
|
return (rcode == 0);
|
|
}
|
|
|
|
|
|
int parse(fp, laddr, faddr)
|
|
FILE *fp;
|
|
struct in_addr *laddr, *faddr;
|
|
{
|
|
int uid, try, rcode;
|
|
struct passwd *pwp;
|
|
char lhostaddr[16];
|
|
char fhostaddr[16];
|
|
char password[33];
|
|
#ifdef INCLUDE_EXTENSIONS
|
|
char arg[33];
|
|
int c;
|
|
#endif
|
|
struct in_addr laddr2;
|
|
struct in_addr faddr2;
|
|
|
|
|
|
if (debug_flag && syslog_flag)
|
|
syslog(LOG_DEBUG, "In function parse()");
|
|
|
|
/*
|
|
** Get the local/foreign port pair from the luser
|
|
*/
|
|
do
|
|
{
|
|
if (debug_flag && syslog_flag)
|
|
syslog(LOG_DEBUG, " Before fscanf()");
|
|
|
|
faddr2 = *faddr;
|
|
laddr2 = *laddr;
|
|
lport = fport = 0;
|
|
lhostaddr[0] = fhostaddr[0] = password[0] = '\0';
|
|
|
|
/* Read query from client */
|
|
rcode = fscanf(fp, " %d , %d", &lport, &fport);
|
|
|
|
#ifdef INCLUDE_EXTENSIONS
|
|
/*
|
|
** Do additional parsing in case of extended request
|
|
*/
|
|
if (rcode == 0)
|
|
{
|
|
rcode = fscanf(fp, "%32[^ \t\n\r:]", arg);
|
|
|
|
/* Skip leading space up to EOF, EOL or non-space char */
|
|
while ((c = getc(fp)) == ' ' || c == '\t')
|
|
;
|
|
|
|
if (rcode <= 0)
|
|
{
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "X-INVALID-REQUEST");
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
** Non-standard extended request, returns with Pidentd
|
|
** version information
|
|
*/
|
|
if (strcmp(arg, "VERSION") == 0)
|
|
{
|
|
printf("%d , %d : ERROR : X-VERSION : %s\r\n", lport, fport,
|
|
version);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
** Non-standard extended proxy request
|
|
*/
|
|
else if (strcmp(arg, "PROXY") == 0 && c == ':')
|
|
{
|
|
/* We have a colon char, check for port numbers */
|
|
rcode = fscanf(fp, " %d , %d : %15[0-9.] , %15[0-9.]",
|
|
&lport, &fport, fhostaddr, lhostaddr);
|
|
|
|
if (!(rcode == 3 || rcode == 4))
|
|
{
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "X-INVALID-REQUEST");
|
|
continue;
|
|
}
|
|
|
|
if (rcode == 4)
|
|
(void) inet_aton(lhostaddr, &laddr2);
|
|
|
|
(void) inet_aton(fhostaddr, &faddr2);
|
|
|
|
proxy(&laddr2, &faddr2, lport, fport, NULL);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
** Non-standard extended remote indirect request
|
|
*/
|
|
else if (strcmp(arg, "REMOTE") == 0 && c == ':')
|
|
{
|
|
/* We have a colon char, check for port numbers */
|
|
rcode = fscanf(fp, " %d , %d", &lport, &fport);
|
|
|
|
/* Skip leading space up to EOF, EOL or non-space char */
|
|
while ((c = getc(fp)) == ' ' || c == '\t')
|
|
;
|
|
|
|
if (rcode != 2 || c != ':')
|
|
{
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "X-INVALID-REQUEST");
|
|
continue;
|
|
}
|
|
|
|
/* We have a colon char, check for addr and password */
|
|
rcode = fscanf(fp, " %15[0-9.] , %32[^ \t\r\n]",
|
|
fhostaddr, password);
|
|
if (rcode > 0)
|
|
rcode += 2;
|
|
else
|
|
{
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "X-INVALID-REQUEST");
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
** Verify that the host originating the indirect request
|
|
** is allowed to do that
|
|
*/
|
|
if (!valid_fhost(faddr, password))
|
|
{
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "X-ACCESS-DENIED");
|
|
continue;
|
|
}
|
|
|
|
(void) inet_aton(fhostaddr, &faddr2);
|
|
}
|
|
|
|
else
|
|
{
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "X-INVALID-REQUEST");
|
|
continue;
|
|
}
|
|
}
|
|
#endif /* EXTENSIONS */
|
|
|
|
if (rcode < 2 || lport < 1 || lport > 65535 || fport < 1 || fport > 65535)
|
|
{
|
|
if (syslog_flag && rcode > 0)
|
|
syslog(LOG_NOTICE, "scanf: invalid-port(s): %d , %d from %s",
|
|
lport, fport, gethost(faddr));
|
|
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "INVALID-PORT");
|
|
continue;
|
|
}
|
|
|
|
if (syslog_flag && verbose_flag)
|
|
syslog(LOG_NOTICE, "request for (%d,%d) from %s",
|
|
lport, fport, gethost(faddr));
|
|
|
|
if (debug_flag && syslog_flag)
|
|
syslog(LOG_DEBUG, " After fscanf(), before k_getuid()");
|
|
|
|
/*
|
|
** Next - get the specific TCP connection and return the
|
|
** uid - user number.
|
|
**
|
|
** Try to fetch the information 5 times incase the
|
|
** kernel changed beneath us and we missed or took
|
|
** a fault.
|
|
*/
|
|
for (try = 0;
|
|
(try < 5 &&
|
|
k_getuid(&faddr2, htons(fport), laddr, htons(lport), &uid) == -1);
|
|
try++)
|
|
;
|
|
|
|
if (try >= 5)
|
|
{
|
|
if (syslog_flag)
|
|
syslog(LOG_DEBUG, "Returned: %d , %d : NO-USER", lport, fport);
|
|
|
|
printf("%d , %d : ERROR : %s\r\n",
|
|
lport, fport,
|
|
unknown_flag ? "UNKNOWN-ERROR" : "NO-USER");
|
|
continue;
|
|
}
|
|
|
|
if (try > 0 && syslog_flag)
|
|
syslog(LOG_NOTICE, "k_getuid retries: %d", try);
|
|
|
|
if (debug_flag && syslog_flag)
|
|
syslog(LOG_DEBUG, " After k_getuid(), before getpwuid()");
|
|
|
|
/*
|
|
** Then we should try to get the username. If that fails we
|
|
** return it as an OTHER identifier
|
|
*/
|
|
pwp = getpwuid(uid);
|
|
|
|
if (!pwp)
|
|
{
|
|
if (syslog_flag)
|
|
syslog(LOG_WARNING, "getpwuid() could not map uid (%d) to name",
|
|
uid);
|
|
|
|
printf("%d , %d : USERID : OTHER%s%s :%d\r\n",
|
|
lport, fport,
|
|
charset_name ? " , " : "",
|
|
charset_name ? charset_name : "",
|
|
uid);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
** Hey! We finally made it!!!
|
|
*/
|
|
if (syslog_flag)
|
|
syslog(LOG_DEBUG, "Successful lookup: %d , %d : %s\n",
|
|
lport, fport, pwp->pw_name);
|
|
|
|
if (noident_flag && check_noident(pwp->pw_dir))
|
|
{
|
|
if (syslog_flag && verbose_flag)
|
|
syslog(LOG_NOTICE, "user %s requested HIDDEN-USER for host %s: %d, %d",
|
|
pwp->pw_name,
|
|
gethost(faddr),
|
|
lport, fport);
|
|
|
|
printf("%d , %d : ERROR : HIDDEN-USER\r\n",
|
|
lport, fport);
|
|
continue;
|
|
}
|
|
|
|
if (number_flag)
|
|
printf("%d , %d : USERID : OTHER%s%s :%d\r\n",
|
|
lport, fport,
|
|
charset_name ? " , " : "",
|
|
charset_name ? charset_name : "",
|
|
uid);
|
|
else
|
|
printf("%d , %d : USERID : %s%s%s :%s\r\n",
|
|
lport, fport,
|
|
other_flag ? "OTHER" : "UNIX",
|
|
charset_name ? " , " : "",
|
|
charset_name ? charset_name : "",
|
|
pwp->pw_name);
|
|
|
|
} while(fflush(stdout), fflush(stderr), multi_flag && eat_whitespace());
|
|
|
|
return 0;
|
|
}
|