mirror of
git://anongit.mindrot.org/openssh.git
synced 2024-11-28 07:14:31 +08:00
3a961dc0d3
- markus@cvs.openbsd.org 2003/06/02 09:17:34 [auth2-hostbased.c auth.c auth-options.c auth-rhosts.c auth-rh-rsa.c] [canohost.c monitor.c servconf.c servconf.h session.c sshd_config] [sshd_config.5] deprecate VerifyReverseMapping since it's dangerous if combined with IP based access control as noted by Mike Harding; replace with a UseDNS option, UseDNS is on by default and includes the VerifyReverseMapping check; with itojun@, provos@, jakob@ and deraadt@ ok deraadt@, djm@ - (djm) Fix portable-specific uses of verify_reverse_mapping too
301 lines
7.4 KiB
C
301 lines
7.4 KiB
C
/*
|
|
* Author: Tatu Ylonen <ylo@cs.hut.fi>
|
|
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
|
|
* All rights reserved
|
|
* As far as I am concerned, the code I have written for this software
|
|
* can be used freely for any purpose. Any derived versions of this
|
|
* software must be clearly marked as such, and if the derived work is
|
|
* incompatible with the protocol description in the RFC file, it must be
|
|
* called by a name other than "ssh" or "Secure Shell".
|
|
*/
|
|
|
|
#include "includes.h"
|
|
RCSID("$OpenBSD: auth-options.c,v 1.28 2003/06/02 09:17:34 markus Exp $");
|
|
|
|
#include "xmalloc.h"
|
|
#include "match.h"
|
|
#include "log.h"
|
|
#include "canohost.h"
|
|
#include "channels.h"
|
|
#include "auth-options.h"
|
|
#include "servconf.h"
|
|
#include "misc.h"
|
|
#include "monitor_wrap.h"
|
|
#include "auth.h"
|
|
|
|
/* Flags set authorized_keys flags */
|
|
int no_port_forwarding_flag = 0;
|
|
int no_agent_forwarding_flag = 0;
|
|
int no_x11_forwarding_flag = 0;
|
|
int no_pty_flag = 0;
|
|
|
|
/* "command=" option. */
|
|
char *forced_command = NULL;
|
|
|
|
/* "environment=" options. */
|
|
struct envstring *custom_environment = NULL;
|
|
|
|
extern ServerOptions options;
|
|
|
|
void
|
|
auth_clear_options(void)
|
|
{
|
|
no_agent_forwarding_flag = 0;
|
|
no_port_forwarding_flag = 0;
|
|
no_pty_flag = 0;
|
|
no_x11_forwarding_flag = 0;
|
|
while (custom_environment) {
|
|
struct envstring *ce = custom_environment;
|
|
custom_environment = ce->next;
|
|
xfree(ce->s);
|
|
xfree(ce);
|
|
}
|
|
if (forced_command) {
|
|
xfree(forced_command);
|
|
forced_command = NULL;
|
|
}
|
|
channel_clear_permitted_opens();
|
|
auth_debug_reset();
|
|
}
|
|
|
|
/*
|
|
* return 1 if access is granted, 0 if not.
|
|
* side effect: sets key option flags
|
|
*/
|
|
int
|
|
auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum)
|
|
{
|
|
const char *cp;
|
|
int i;
|
|
|
|
/* reset options */
|
|
auth_clear_options();
|
|
|
|
if (!opts)
|
|
return 1;
|
|
|
|
while (*opts && *opts != ' ' && *opts != '\t') {
|
|
cp = "no-port-forwarding";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
auth_debug_add("Port forwarding disabled.");
|
|
no_port_forwarding_flag = 1;
|
|
opts += strlen(cp);
|
|
goto next_option;
|
|
}
|
|
cp = "no-agent-forwarding";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
auth_debug_add("Agent forwarding disabled.");
|
|
no_agent_forwarding_flag = 1;
|
|
opts += strlen(cp);
|
|
goto next_option;
|
|
}
|
|
cp = "no-X11-forwarding";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
auth_debug_add("X11 forwarding disabled.");
|
|
no_x11_forwarding_flag = 1;
|
|
opts += strlen(cp);
|
|
goto next_option;
|
|
}
|
|
cp = "no-pty";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
auth_debug_add("Pty allocation disabled.");
|
|
no_pty_flag = 1;
|
|
opts += strlen(cp);
|
|
goto next_option;
|
|
}
|
|
cp = "command=\"";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
opts += strlen(cp);
|
|
forced_command = xmalloc(strlen(opts) + 1);
|
|
i = 0;
|
|
while (*opts) {
|
|
if (*opts == '"')
|
|
break;
|
|
if (*opts == '\\' && opts[1] == '"') {
|
|
opts += 2;
|
|
forced_command[i++] = '"';
|
|
continue;
|
|
}
|
|
forced_command[i++] = *opts++;
|
|
}
|
|
if (!*opts) {
|
|
debug("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
auth_debug_add("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
xfree(forced_command);
|
|
forced_command = NULL;
|
|
goto bad_option;
|
|
}
|
|
forced_command[i] = 0;
|
|
auth_debug_add("Forced command: %.900s", forced_command);
|
|
opts++;
|
|
goto next_option;
|
|
}
|
|
cp = "environment=\"";
|
|
if (options.permit_user_env &&
|
|
strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
char *s;
|
|
struct envstring *new_envstring;
|
|
|
|
opts += strlen(cp);
|
|
s = xmalloc(strlen(opts) + 1);
|
|
i = 0;
|
|
while (*opts) {
|
|
if (*opts == '"')
|
|
break;
|
|
if (*opts == '\\' && opts[1] == '"') {
|
|
opts += 2;
|
|
s[i++] = '"';
|
|
continue;
|
|
}
|
|
s[i++] = *opts++;
|
|
}
|
|
if (!*opts) {
|
|
debug("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
auth_debug_add("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
xfree(s);
|
|
goto bad_option;
|
|
}
|
|
s[i] = 0;
|
|
auth_debug_add("Adding to environment: %.900s", s);
|
|
debug("Adding to environment: %.900s", s);
|
|
opts++;
|
|
new_envstring = xmalloc(sizeof(struct envstring));
|
|
new_envstring->s = s;
|
|
new_envstring->next = custom_environment;
|
|
custom_environment = new_envstring;
|
|
goto next_option;
|
|
}
|
|
cp = "from=\"";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
const char *remote_ip = get_remote_ipaddr();
|
|
const char *remote_host = get_canonical_hostname(
|
|
options.use_dns);
|
|
char *patterns = xmalloc(strlen(opts) + 1);
|
|
|
|
opts += strlen(cp);
|
|
i = 0;
|
|
while (*opts) {
|
|
if (*opts == '"')
|
|
break;
|
|
if (*opts == '\\' && opts[1] == '"') {
|
|
opts += 2;
|
|
patterns[i++] = '"';
|
|
continue;
|
|
}
|
|
patterns[i++] = *opts++;
|
|
}
|
|
if (!*opts) {
|
|
debug("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
auth_debug_add("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
xfree(patterns);
|
|
goto bad_option;
|
|
}
|
|
patterns[i] = 0;
|
|
opts++;
|
|
if (match_host_and_ip(remote_host, remote_ip,
|
|
patterns) != 1) {
|
|
xfree(patterns);
|
|
logit("Authentication tried for %.100s with "
|
|
"correct key but not from a permitted "
|
|
"host (host=%.200s, ip=%.200s).",
|
|
pw->pw_name, remote_host, remote_ip);
|
|
auth_debug_add("Your host '%.200s' is not "
|
|
"permitted to use this key for login.",
|
|
remote_host);
|
|
/* deny access */
|
|
return 0;
|
|
}
|
|
xfree(patterns);
|
|
/* Host name matches. */
|
|
goto next_option;
|
|
}
|
|
cp = "permitopen=\"";
|
|
if (strncasecmp(opts, cp, strlen(cp)) == 0) {
|
|
char host[256], sport[6];
|
|
u_short port;
|
|
char *patterns = xmalloc(strlen(opts) + 1);
|
|
|
|
opts += strlen(cp);
|
|
i = 0;
|
|
while (*opts) {
|
|
if (*opts == '"')
|
|
break;
|
|
if (*opts == '\\' && opts[1] == '"') {
|
|
opts += 2;
|
|
patterns[i++] = '"';
|
|
continue;
|
|
}
|
|
patterns[i++] = *opts++;
|
|
}
|
|
if (!*opts) {
|
|
debug("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
auth_debug_add("%.100s, line %lu: missing end quote",
|
|
file, linenum);
|
|
xfree(patterns);
|
|
goto bad_option;
|
|
}
|
|
patterns[i] = 0;
|
|
opts++;
|
|
if (sscanf(patterns, "%255[^:]:%5[0-9]", host, sport) != 2 &&
|
|
sscanf(patterns, "%255[^/]/%5[0-9]", host, sport) != 2) {
|
|
debug("%.100s, line %lu: Bad permitopen specification "
|
|
"<%.100s>", file, linenum, patterns);
|
|
auth_debug_add("%.100s, line %lu: "
|
|
"Bad permitopen specification", file, linenum);
|
|
xfree(patterns);
|
|
goto bad_option;
|
|
}
|
|
if ((port = a2port(sport)) == 0) {
|
|
debug("%.100s, line %lu: Bad permitopen port <%.100s>",
|
|
file, linenum, sport);
|
|
auth_debug_add("%.100s, line %lu: "
|
|
"Bad permitopen port", file, linenum);
|
|
xfree(patterns);
|
|
goto bad_option;
|
|
}
|
|
if (options.allow_tcp_forwarding)
|
|
channel_add_permitted_opens(host, port);
|
|
xfree(patterns);
|
|
goto next_option;
|
|
}
|
|
next_option:
|
|
/*
|
|
* Skip the comma, and move to the next option
|
|
* (or break out if there are no more).
|
|
*/
|
|
if (!*opts)
|
|
fatal("Bugs in auth-options.c option processing.");
|
|
if (*opts == ' ' || *opts == '\t')
|
|
break; /* End of options. */
|
|
if (*opts != ',')
|
|
goto bad_option;
|
|
opts++;
|
|
/* Process the next option. */
|
|
}
|
|
|
|
if (!use_privsep)
|
|
auth_debug_send();
|
|
|
|
/* grant access */
|
|
return 1;
|
|
|
|
bad_option:
|
|
logit("Bad options in %.100s file, line %lu: %.50s",
|
|
file, linenum, opts);
|
|
auth_debug_add("Bad options in %.100s file, line %lu: %.50s",
|
|
file, linenum, opts);
|
|
|
|
if (!use_privsep)
|
|
auth_debug_send();
|
|
|
|
/* deny access */
|
|
return 0;
|
|
}
|