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-rw-r--r--debian/patches/gssapi.patch3146
1 files changed, 3146 insertions, 0 deletions
diff --git a/debian/patches/gssapi.patch b/debian/patches/gssapi.patch
new file mode 100644
index 000000000..90a21db99
--- /dev/null
+++ b/debian/patches/gssapi.patch
@@ -0,0 +1,3146 @@
1From 429c595dbaff7f7c2b3a53fe4235211f6d788025 Mon Sep 17 00:00:00 2001
2From: Simon Wilkinson <simon@sxw.org.uk>
3Date: Sun, 9 Feb 2014 16:09:48 +0000
4Subject: GSSAPI key exchange support
5
6This patch has been rejected upstream: "None of the OpenSSH developers are
7in favour of adding this, and this situation has not changed for several
8years. This is not a slight on Simon's patch, which is of fine quality, but
9just that a) we don't trust GSSAPI implementations that much and b) we don't
10like adding new KEX since they are pre-auth attack surface. This one is
11particularly scary, since it requires hooks out to typically root-owned
12system resources."
13
14However, quite a lot of people rely on this in Debian, and it's better to
15have it merged into the main openssh package rather than having separate
16-krb5 packages (as we used to have). It seems to have a generally good
17security history.
18
19Bug: https://bugzilla.mindrot.org/show_bug.cgi?id=1242
20Last-Updated: 2014-03-19
21
22Patch-Name: gssapi.patch
23---
24 ChangeLog.gssapi | 113 +++++++++++++++++++
25 Makefile.in | 3 +-
26 auth-krb5.c | 17 ++-
27 auth2-gss.c | 48 +++++++-
28 auth2.c | 2 +
29 clientloop.c | 13 +++
30 config.h.in | 6 +
31 configure | 57 ++++++++++
32 configure.ac | 24 ++++
33 gss-genr.c | 275 ++++++++++++++++++++++++++++++++++++++++++++-
34 gss-serv-krb5.c | 85 ++++++++++++--
35 gss-serv.c | 221 +++++++++++++++++++++++++++++++-----
36 kex.c | 16 +++
37 kex.h | 14 +++
38 kexgssc.c | 332 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
39 kexgsss.c | 289 ++++++++++++++++++++++++++++++++++++++++++++++++
40 key.c | 3 +-
41 key.h | 1 +
42 monitor.c | 108 +++++++++++++++++-
43 monitor.h | 3 +
44 monitor_wrap.c | 47 +++++++-
45 monitor_wrap.h | 4 +-
46 readconf.c | 42 +++++++
47 readconf.h | 5 +
48 servconf.c | 38 ++++++-
49 servconf.h | 3 +
50 ssh-gss.h | 41 ++++++-
51 ssh_config | 2 +
52 ssh_config.5 | 34 +++++-
53 sshconnect2.c | 124 ++++++++++++++++++++-
54 sshd.c | 110 ++++++++++++++++++
55 sshd_config | 2 +
56 sshd_config.5 | 28 +++++
57 33 files changed, 2051 insertions(+), 59 deletions(-)
58 create mode 100644 ChangeLog.gssapi
59 create mode 100644 kexgssc.c
60 create mode 100644 kexgsss.c
61
62diff --git a/ChangeLog.gssapi b/ChangeLog.gssapi
63new file mode 100644
64index 0000000..f117a33
65--- /dev/null
66+++ b/ChangeLog.gssapi
67@@ -0,0 +1,113 @@
68+20110101
69+ - Finally update for OpenSSH 5.6p1
70+ - Add GSSAPIServerIdentity option from Jim Basney
71+
72+20100308
73+ - [ Makefile.in, key.c, key.h ]
74+ Updates for OpenSSH 5.4p1
75+ - [ servconf.c ]
76+ Include GSSAPI options in the sshd -T configuration dump, and flag
77+ some older configuration options as being unsupported. Thanks to Colin
78+ Watson.
79+ -
80+
81+20100124
82+ - [ sshconnect2.c ]
83+ Adapt to deal with additional element in Authmethod structure. Thanks to
84+ Colin Watson
85+
86+20090615
87+ - [ gss-genr.c gss-serv.c kexgssc.c kexgsss.c monitor.c sshconnect2.c
88+ sshd.c ]
89+ Fix issues identified by Greg Hudson following a code review
90+ Check return value of gss_indicate_mechs
91+ Protect GSSAPI calls in monitor, so they can only be used if enabled
92+ Check return values of bignum functions in key exchange
93+ Use BN_clear_free to clear other side's DH value
94+ Make ssh_gssapi_id_kex more robust
95+ Only configure kex table pointers if GSSAPI is enabled
96+ Don't leak mechanism list, or gss mechanism list
97+ Cast data.length before printing
98+ If serverkey isn't provided, use an empty string, rather than NULL
99+
100+20090201
101+ - [ gss-genr.c gss-serv.c kex.h kexgssc.c readconf.c readconf.h ssh-gss.h
102+ ssh_config.5 sshconnet2.c ]
103+ Add support for the GSSAPIClientIdentity option, which allows the user
104+ to specify which GSSAPI identity to use to contact a given server
105+
106+20080404
107+ - [ gss-serv.c ]
108+ Add code to actually implement GSSAPIStrictAcceptCheck, which had somehow
109+ been omitted from a previous version of this patch. Reported by Borislav
110+ Stoichkov
111+
112+20070317
113+ - [ gss-serv-krb5.c ]
114+ Remove C99ism, where new_ccname was being declared in the middle of a
115+ function
116+
117+20061220
118+ - [ servconf.c ]
119+ Make default for GSSAPIStrictAcceptorCheck be Yes, to match previous, and
120+ documented, behaviour. Reported by Dan Watson.
121+
122+20060910
123+ - [ gss-genr.c kexgssc.c kexgsss.c kex.h monitor.c sshconnect2.c sshd.c
124+ ssh-gss.h ]
125+ add support for gss-group14-sha1 key exchange mechanisms
126+ - [ gss-serv.c servconf.c servconf.h sshd_config sshd_config.5 ]
127+ Add GSSAPIStrictAcceptorCheck option to allow the disabling of
128+ acceptor principal checking on multi-homed machines.
129+ <Bugzilla #928>
130+ - [ sshd_config ssh_config ]
131+ Add settings for GSSAPIKeyExchange and GSSAPITrustDNS to the sample
132+ configuration files
133+ - [ kexgss.c kegsss.c sshconnect2.c sshd.c ]
134+ Code cleanup. Replace strlen/xmalloc/snprintf sequences with xasprintf()
135+ Limit length of error messages displayed by client
136+
137+20060909
138+ - [ gss-genr.c gss-serv.c ]
139+ move ssh_gssapi_acquire_cred() and ssh_gssapi_server_ctx to be server
140+ only, where they belong
141+ <Bugzilla #1225>
142+
143+20060829
144+ - [ gss-serv-krb5.c ]
145+ Fix CCAPI credentials cache name when creating KRB5CCNAME environment
146+ variable
147+
148+20060828
149+ - [ gss-genr.c ]
150+ Avoid Heimdal context freeing problem
151+ <Fixed upstream 20060829>
152+
153+20060818
154+ - [ gss-genr.c ssh-gss.h sshconnect2.c ]
155+ Make sure that SPENGO is disabled
156+ <Bugzilla #1218 - Fixed upstream 20060818>
157+
158+20060421
159+ - [ gssgenr.c, sshconnect2.c ]
160+ a few type changes (signed versus unsigned, int versus size_t) to
161+ fix compiler errors/warnings
162+ (from jbasney AT ncsa.uiuc.edu)
163+ - [ kexgssc.c, sshconnect2.c ]
164+ fix uninitialized variable warnings
165+ (from jbasney AT ncsa.uiuc.edu)
166+ - [ gssgenr.c ]
167+ pass oid to gss_display_status (helpful when using GSSAPI mechglue)
168+ (from jbasney AT ncsa.uiuc.edu)
169+ <Bugzilla #1220 >
170+ - [ gss-serv-krb5.c ]
171+ #ifdef HAVE_GSSAPI_KRB5 should be #ifdef HAVE_GSSAPI_KRB5_H
172+ (from jbasney AT ncsa.uiuc.edu)
173+ <Fixed upstream 20060304>
174+ - [ readconf.c, readconf.h, ssh_config.5, sshconnect2.c
175+ add client-side GssapiKeyExchange option
176+ (from jbasney AT ncsa.uiuc.edu)
177+ - [ sshconnect2.c ]
178+ add support for GssapiTrustDns option for gssapi-with-mic
179+ (from jbasney AT ncsa.uiuc.edu)
180+ <gssapi-with-mic support is Bugzilla #1008>
181diff --git a/Makefile.in b/Makefile.in
182index a8aa127..35c6fd6 100644
183--- a/Makefile.in
184+++ b/Makefile.in
185@@ -72,6 +72,7 @@ LIBSSH_OBJS=authfd.o authfile.o bufaux.o bufbn.o buffer.o \
186 atomicio.o key.o dispatch.o kex.o mac.o uidswap.o uuencode.o misc.o \
187 monitor_fdpass.o rijndael.o ssh-dss.o ssh-ecdsa.o ssh-rsa.o dh.o \
188 kexdh.o kexgex.o kexdhc.o kexgexc.o bufec.o kexecdh.o kexecdhc.o \
189+ kexgssc.o \
190 msg.o progressmeter.o dns.o entropy.o gss-genr.o umac.o umac128.o \
191 jpake.o schnorr.o ssh-pkcs11.o krl.o smult_curve25519_ref.o \
192 kexc25519.o kexc25519c.o poly1305.o chacha.o cipher-chachapoly.o \
193@@ -91,7 +92,7 @@ SSHDOBJS=sshd.o auth-rhosts.o auth-passwd.o auth-rsa.o auth-rh-rsa.o \
194 auth2-none.o auth2-passwd.o auth2-pubkey.o auth2-jpake.o \
195 monitor_mm.o monitor.o monitor_wrap.o kexdhs.o kexgexs.o kexecdhs.o \
196 kexc25519s.o auth-krb5.o \
197- auth2-gss.o gss-serv.o gss-serv-krb5.o \
198+ auth2-gss.o gss-serv.o gss-serv-krb5.o kexgsss.o \
199 loginrec.o auth-pam.o auth-shadow.o auth-sia.o md5crypt.o \
200 sftp-server.o sftp-common.o \
201 roaming_common.o roaming_serv.o \
202diff --git a/auth-krb5.c b/auth-krb5.c
203index 6c62bdf..69a1a53 100644
204--- a/auth-krb5.c
205+++ b/auth-krb5.c
206@@ -182,8 +182,13 @@ auth_krb5_password(Authctxt *authctxt, const char *password)
207
208 len = strlen(authctxt->krb5_ticket_file) + 6;
209 authctxt->krb5_ccname = xmalloc(len);
210+#ifdef USE_CCAPI
211+ snprintf(authctxt->krb5_ccname, len, "API:%s",
212+ authctxt->krb5_ticket_file);
213+#else
214 snprintf(authctxt->krb5_ccname, len, "FILE:%s",
215 authctxt->krb5_ticket_file);
216+#endif
217
218 #ifdef USE_PAM
219 if (options.use_pam)
220@@ -240,15 +245,22 @@ krb5_cleanup_proc(Authctxt *authctxt)
221 #ifndef HEIMDAL
222 krb5_error_code
223 ssh_krb5_cc_gen(krb5_context ctx, krb5_ccache *ccache) {
224- int tmpfd, ret, oerrno;
225+ int ret, oerrno;
226 char ccname[40];
227 mode_t old_umask;
228+#ifdef USE_CCAPI
229+ char cctemplate[] = "API:krb5cc_%d";
230+#else
231+ char cctemplate[] = "FILE:/tmp/krb5cc_%d_XXXXXXXXXX";
232+ int tmpfd;
233+#endif
234
235 ret = snprintf(ccname, sizeof(ccname),
236- "FILE:/tmp/krb5cc_%d_XXXXXXXXXX", geteuid());
237+ cctemplate, geteuid());
238 if (ret < 0 || (size_t)ret >= sizeof(ccname))
239 return ENOMEM;
240
241+#ifndef USE_CCAPI
242 old_umask = umask(0177);
243 tmpfd = mkstemp(ccname + strlen("FILE:"));
244 oerrno = errno;
245@@ -265,6 +277,7 @@ ssh_krb5_cc_gen(krb5_context ctx, krb5_ccache *ccache) {
246 return oerrno;
247 }
248 close(tmpfd);
249+#endif
250
251 return (krb5_cc_resolve(ctx, ccname, ccache));
252 }
253diff --git a/auth2-gss.c b/auth2-gss.c
254index 638d8f8..b8db820 100644
255--- a/auth2-gss.c
256+++ b/auth2-gss.c
257@@ -1,7 +1,7 @@
258 /* $OpenBSD: auth2-gss.c,v 1.20 2013/05/17 00:13:13 djm Exp $ */
259
260 /*
261- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
262+ * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
263 *
264 * Redistribution and use in source and binary forms, with or without
265 * modification, are permitted provided that the following conditions
266@@ -52,6 +52,40 @@ static void input_gssapi_mic(int type, u_int32_t plen, void *ctxt);
267 static void input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt);
268 static void input_gssapi_errtok(int, u_int32_t, void *);
269
270+/*
271+ * The 'gssapi_keyex' userauth mechanism.
272+ */
273+static int
274+userauth_gsskeyex(Authctxt *authctxt)
275+{
276+ int authenticated = 0;
277+ Buffer b;
278+ gss_buffer_desc mic, gssbuf;
279+ u_int len;
280+
281+ mic.value = packet_get_string(&len);
282+ mic.length = len;
283+
284+ packet_check_eom();
285+
286+ ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
287+ "gssapi-keyex");
288+
289+ gssbuf.value = buffer_ptr(&b);
290+ gssbuf.length = buffer_len(&b);
291+
292+ /* gss_kex_context is NULL with privsep, so we can't check it here */
293+ if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gss_kex_context,
294+ &gssbuf, &mic))))
295+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
296+ authctxt->pw));
297+
298+ buffer_free(&b);
299+ free(mic.value);
300+
301+ return (authenticated);
302+}
303+
304 /*
305 * We only support those mechanisms that we know about (ie ones that we know
306 * how to check local user kuserok and the like)
307@@ -240,7 +274,8 @@ input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt)
308
309 packet_check_eom();
310
311- authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
312+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
313+ authctxt->pw));
314
315 authctxt->postponed = 0;
316 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
317@@ -275,7 +310,8 @@ input_gssapi_mic(int type, u_int32_t plen, void *ctxt)
318 gssbuf.length = buffer_len(&b);
319
320 if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gssctxt, &gssbuf, &mic))))
321- authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
322+ authenticated =
323+ PRIVSEP(ssh_gssapi_userok(authctxt->user, authctxt->pw));
324 else
325 logit("GSSAPI MIC check failed");
326
327@@ -290,6 +326,12 @@ input_gssapi_mic(int type, u_int32_t plen, void *ctxt)
328 userauth_finish(authctxt, authenticated, "gssapi-with-mic", NULL);
329 }
330
331+Authmethod method_gsskeyex = {
332+ "gssapi-keyex",
333+ userauth_gsskeyex,
334+ &options.gss_authentication
335+};
336+
337 Authmethod method_gssapi = {
338 "gssapi-with-mic",
339 userauth_gssapi,
340diff --git a/auth2.c b/auth2.c
341index f0cab8c..6ed8f04 100644
342--- a/auth2.c
343+++ b/auth2.c
344@@ -69,6 +69,7 @@ extern Authmethod method_passwd;
345 extern Authmethod method_kbdint;
346 extern Authmethod method_hostbased;
347 #ifdef GSSAPI
348+extern Authmethod method_gsskeyex;
349 extern Authmethod method_gssapi;
350 #endif
351 #ifdef JPAKE
352@@ -79,6 +80,7 @@ Authmethod *authmethods[] = {
353 &method_none,
354 &method_pubkey,
355 #ifdef GSSAPI
356+ &method_gsskeyex,
357 &method_gssapi,
358 #endif
359 #ifdef JPAKE
360diff --git a/clientloop.c b/clientloop.c
361index f30c8b6..cc23e35 100644
362--- a/clientloop.c
363+++ b/clientloop.c
364@@ -111,6 +111,10 @@
365 #include "msg.h"
366 #include "roaming.h"
367
368+#ifdef GSSAPI
369+#include "ssh-gss.h"
370+#endif
371+
372 /* import options */
373 extern Options options;
374
375@@ -1608,6 +1612,15 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
376 /* Do channel operations unless rekeying in progress. */
377 if (!rekeying) {
378 channel_after_select(readset, writeset);
379+
380+#ifdef GSSAPI
381+ if (options.gss_renewal_rekey &&
382+ ssh_gssapi_credentials_updated(NULL)) {
383+ debug("credentials updated - forcing rekey");
384+ need_rekeying = 1;
385+ }
386+#endif
387+
388 if (need_rekeying || packet_need_rekeying()) {
389 debug("need rekeying");
390 xxx_kex->done = 0;
391diff --git a/config.h.in b/config.h.in
392index 075c619..906e549 100644
393--- a/config.h.in
394+++ b/config.h.in
395@@ -1616,6 +1616,9 @@
396 /* Use btmp to log bad logins */
397 #undef USE_BTMP
398
399+/* platform uses an in-memory credentials cache */
400+#undef USE_CCAPI
401+
402 /* Use libedit for sftp */
403 #undef USE_LIBEDIT
404
405@@ -1631,6 +1634,9 @@
406 /* Use PIPES instead of a socketpair() */
407 #undef USE_PIPES
408
409+/* platform has the Security Authorization Session API */
410+#undef USE_SECURITY_SESSION_API
411+
412 /* Define if you have Solaris process contracts */
413 #undef USE_SOLARIS_PROCESS_CONTRACTS
414
415diff --git a/configure b/configure
416index 2d714ac..5a9db2d 100755
417--- a/configure
418+++ b/configure
419@@ -7170,6 +7170,63 @@ $as_echo "#define SSH_TUN_COMPAT_AF 1" >>confdefs.h
420
421 $as_echo "#define SSH_TUN_PREPEND_AF 1" >>confdefs.h
422
423+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking if we have the Security Authorization Session API" >&5
424+$as_echo_n "checking if we have the Security Authorization Session API... " >&6; }
425+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
426+/* end confdefs.h. */
427+#include <Security/AuthSession.h>
428+int
429+main ()
430+{
431+SessionCreate(0, 0);
432+ ;
433+ return 0;
434+}
435+_ACEOF
436+if ac_fn_c_try_compile "$LINENO"; then :
437+ ac_cv_use_security_session_api="yes"
438+
439+$as_echo "#define USE_SECURITY_SESSION_API 1" >>confdefs.h
440+
441+ LIBS="$LIBS -framework Security"
442+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
443+$as_echo "yes" >&6; }
444+else
445+ ac_cv_use_security_session_api="no"
446+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
447+$as_echo "no" >&6; }
448+fi
449+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
450+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking if we have an in-memory credentials cache" >&5
451+$as_echo_n "checking if we have an in-memory credentials cache... " >&6; }
452+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
453+/* end confdefs.h. */
454+#include <Kerberos/Kerberos.h>
455+int
456+main ()
457+{
458+cc_context_t c;
459+ (void) cc_initialize (&c, 0, NULL, NULL);
460+ ;
461+ return 0;
462+}
463+_ACEOF
464+if ac_fn_c_try_compile "$LINENO"; then :
465+
466+$as_echo "#define USE_CCAPI 1" >>confdefs.h
467+
468+ LIBS="$LIBS -framework Security"
469+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
470+$as_echo "yes" >&6; }
471+ if test "x$ac_cv_use_security_session_api" = "xno"; then
472+ as_fn_error $? "*** Need a security framework to use the credentials cache API ***" "$LINENO" 5
473+ fi
474+else
475+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
476+$as_echo "no" >&6; }
477+
478+fi
479+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
480
481 ac_fn_c_check_decl "$LINENO" "AU_IPv4" "ac_cv_have_decl_AU_IPv4" "$ac_includes_default"
482 if test "x$ac_cv_have_decl_AU_IPv4" = xyes; then :
483diff --git a/configure.ac b/configure.ac
484index dfd32cd..90eebf5 100644
485--- a/configure.ac
486+++ b/configure.ac
487@@ -584,6 +584,30 @@ main() { if (NSVersionOfRunTimeLibrary("System") >= (60 << 16))
488 [Use tunnel device compatibility to OpenBSD])
489 AC_DEFINE([SSH_TUN_PREPEND_AF], [1],
490 [Prepend the address family to IP tunnel traffic])
491+ AC_MSG_CHECKING([if we have the Security Authorization Session API])
492+ AC_TRY_COMPILE([#include <Security/AuthSession.h>],
493+ [SessionCreate(0, 0);],
494+ [ac_cv_use_security_session_api="yes"
495+ AC_DEFINE([USE_SECURITY_SESSION_API], [1],
496+ [platform has the Security Authorization Session API])
497+ LIBS="$LIBS -framework Security"
498+ AC_MSG_RESULT([yes])],
499+ [ac_cv_use_security_session_api="no"
500+ AC_MSG_RESULT([no])])
501+ AC_MSG_CHECKING([if we have an in-memory credentials cache])
502+ AC_TRY_COMPILE(
503+ [#include <Kerberos/Kerberos.h>],
504+ [cc_context_t c;
505+ (void) cc_initialize (&c, 0, NULL, NULL);],
506+ [AC_DEFINE([USE_CCAPI], [1],
507+ [platform uses an in-memory credentials cache])
508+ LIBS="$LIBS -framework Security"
509+ AC_MSG_RESULT([yes])
510+ if test "x$ac_cv_use_security_session_api" = "xno"; then
511+ AC_MSG_ERROR([*** Need a security framework to use the credentials cache API ***])
512+ fi],
513+ [AC_MSG_RESULT([no])]
514+ )
515 m4_pattern_allow([AU_IPv])
516 AC_CHECK_DECL([AU_IPv4], [],
517 AC_DEFINE([AU_IPv4], [0], [System only supports IPv4 audit records])
518diff --git a/gss-genr.c b/gss-genr.c
519index b39281b..1e569ad 100644
520--- a/gss-genr.c
521+++ b/gss-genr.c
522@@ -1,7 +1,7 @@
523 /* $OpenBSD: gss-genr.c,v 1.22 2013/11/08 00:39:15 djm Exp $ */
524
525 /*
526- * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
527+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
528 *
529 * Redistribution and use in source and binary forms, with or without
530 * modification, are permitted provided that the following conditions
531@@ -39,12 +39,167 @@
532 #include "buffer.h"
533 #include "log.h"
534 #include "ssh2.h"
535+#include "cipher.h"
536+#include "key.h"
537+#include "kex.h"
538+#include <openssl/evp.h>
539
540 #include "ssh-gss.h"
541
542 extern u_char *session_id2;
543 extern u_int session_id2_len;
544
545+typedef struct {
546+ char *encoded;
547+ gss_OID oid;
548+} ssh_gss_kex_mapping;
549+
550+/*
551+ * XXX - It would be nice to find a more elegant way of handling the
552+ * XXX passing of the key exchange context to the userauth routines
553+ */
554+
555+Gssctxt *gss_kex_context = NULL;
556+
557+static ssh_gss_kex_mapping *gss_enc2oid = NULL;
558+
559+int
560+ssh_gssapi_oid_table_ok(void) {
561+ return (gss_enc2oid != NULL);
562+}
563+
564+/*
565+ * Return a list of the gss-group1-sha1 mechanisms supported by this program
566+ *
567+ * We test mechanisms to ensure that we can use them, to avoid starting
568+ * a key exchange with a bad mechanism
569+ */
570+
571+char *
572+ssh_gssapi_client_mechanisms(const char *host, const char *client) {
573+ gss_OID_set gss_supported;
574+ OM_uint32 min_status;
575+
576+ if (GSS_ERROR(gss_indicate_mechs(&min_status, &gss_supported)))
577+ return NULL;
578+
579+ return(ssh_gssapi_kex_mechs(gss_supported, ssh_gssapi_check_mechanism,
580+ host, client));
581+}
582+
583+char *
584+ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
585+ const char *host, const char *client) {
586+ Buffer buf;
587+ size_t i;
588+ int oidpos, enclen;
589+ char *mechs, *encoded;
590+ u_char digest[EVP_MAX_MD_SIZE];
591+ char deroid[2];
592+ const EVP_MD *evp_md = EVP_md5();
593+ EVP_MD_CTX md;
594+
595+ if (gss_enc2oid != NULL) {
596+ for (i = 0; gss_enc2oid[i].encoded != NULL; i++)
597+ free(gss_enc2oid[i].encoded);
598+ free(gss_enc2oid);
599+ }
600+
601+ gss_enc2oid = xmalloc(sizeof(ssh_gss_kex_mapping) *
602+ (gss_supported->count + 1));
603+
604+ buffer_init(&buf);
605+
606+ oidpos = 0;
607+ for (i = 0; i < gss_supported->count; i++) {
608+ if (gss_supported->elements[i].length < 128 &&
609+ (*check)(NULL, &(gss_supported->elements[i]), host, client)) {
610+
611+ deroid[0] = SSH_GSS_OIDTYPE;
612+ deroid[1] = gss_supported->elements[i].length;
613+
614+ EVP_DigestInit(&md, evp_md);
615+ EVP_DigestUpdate(&md, deroid, 2);
616+ EVP_DigestUpdate(&md,
617+ gss_supported->elements[i].elements,
618+ gss_supported->elements[i].length);
619+ EVP_DigestFinal(&md, digest, NULL);
620+
621+ encoded = xmalloc(EVP_MD_size(evp_md) * 2);
622+ enclen = __b64_ntop(digest, EVP_MD_size(evp_md),
623+ encoded, EVP_MD_size(evp_md) * 2);
624+
625+ if (oidpos != 0)
626+ buffer_put_char(&buf, ',');
627+
628+ buffer_append(&buf, KEX_GSS_GEX_SHA1_ID,
629+ sizeof(KEX_GSS_GEX_SHA1_ID) - 1);
630+ buffer_append(&buf, encoded, enclen);
631+ buffer_put_char(&buf, ',');
632+ buffer_append(&buf, KEX_GSS_GRP1_SHA1_ID,
633+ sizeof(KEX_GSS_GRP1_SHA1_ID) - 1);
634+ buffer_append(&buf, encoded, enclen);
635+ buffer_put_char(&buf, ',');
636+ buffer_append(&buf, KEX_GSS_GRP14_SHA1_ID,
637+ sizeof(KEX_GSS_GRP14_SHA1_ID) - 1);
638+ buffer_append(&buf, encoded, enclen);
639+
640+ gss_enc2oid[oidpos].oid = &(gss_supported->elements[i]);
641+ gss_enc2oid[oidpos].encoded = encoded;
642+ oidpos++;
643+ }
644+ }
645+ gss_enc2oid[oidpos].oid = NULL;
646+ gss_enc2oid[oidpos].encoded = NULL;
647+
648+ buffer_put_char(&buf, '\0');
649+
650+ mechs = xmalloc(buffer_len(&buf));
651+ buffer_get(&buf, mechs, buffer_len(&buf));
652+ buffer_free(&buf);
653+
654+ if (strlen(mechs) == 0) {
655+ free(mechs);
656+ mechs = NULL;
657+ }
658+
659+ return (mechs);
660+}
661+
662+gss_OID
663+ssh_gssapi_id_kex(Gssctxt *ctx, char *name, int kex_type) {
664+ int i = 0;
665+
666+ switch (kex_type) {
667+ case KEX_GSS_GRP1_SHA1:
668+ if (strlen(name) < sizeof(KEX_GSS_GRP1_SHA1_ID))
669+ return GSS_C_NO_OID;
670+ name += sizeof(KEX_GSS_GRP1_SHA1_ID) - 1;
671+ break;
672+ case KEX_GSS_GRP14_SHA1:
673+ if (strlen(name) < sizeof(KEX_GSS_GRP14_SHA1_ID))
674+ return GSS_C_NO_OID;
675+ name += sizeof(KEX_GSS_GRP14_SHA1_ID) - 1;
676+ break;
677+ case KEX_GSS_GEX_SHA1:
678+ if (strlen(name) < sizeof(KEX_GSS_GEX_SHA1_ID))
679+ return GSS_C_NO_OID;
680+ name += sizeof(KEX_GSS_GEX_SHA1_ID) - 1;
681+ break;
682+ default:
683+ return GSS_C_NO_OID;
684+ }
685+
686+ while (gss_enc2oid[i].encoded != NULL &&
687+ strcmp(name, gss_enc2oid[i].encoded) != 0)
688+ i++;
689+
690+ if (gss_enc2oid[i].oid != NULL && ctx != NULL)
691+ ssh_gssapi_set_oid(ctx, gss_enc2oid[i].oid);
692+
693+ return gss_enc2oid[i].oid;
694+}
695+
696 /* Check that the OID in a data stream matches that in the context */
697 int
698 ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
699@@ -197,7 +352,7 @@ ssh_gssapi_init_ctx(Gssctxt *ctx, int deleg_creds, gss_buffer_desc *recv_tok,
700 }
701
702 ctx->major = gss_init_sec_context(&ctx->minor,
703- GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
704+ ctx->client_creds, &ctx->context, ctx->name, ctx->oid,
705 GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG | deleg_flag,
706 0, NULL, recv_tok, NULL, send_tok, flags, NULL);
707
708@@ -227,8 +382,42 @@ ssh_gssapi_import_name(Gssctxt *ctx, const char *host)
709 }
710
711 OM_uint32
712+ssh_gssapi_client_identity(Gssctxt *ctx, const char *name)
713+{
714+ gss_buffer_desc gssbuf;
715+ gss_name_t gssname;
716+ OM_uint32 status;
717+ gss_OID_set oidset;
718+
719+ gssbuf.value = (void *) name;
720+ gssbuf.length = strlen(gssbuf.value);
721+
722+ gss_create_empty_oid_set(&status, &oidset);
723+ gss_add_oid_set_member(&status, ctx->oid, &oidset);
724+
725+ ctx->major = gss_import_name(&ctx->minor, &gssbuf,
726+ GSS_C_NT_USER_NAME, &gssname);
727+
728+ if (!ctx->major)
729+ ctx->major = gss_acquire_cred(&ctx->minor,
730+ gssname, 0, oidset, GSS_C_INITIATE,
731+ &ctx->client_creds, NULL, NULL);
732+
733+ gss_release_name(&status, &gssname);
734+ gss_release_oid_set(&status, &oidset);
735+
736+ if (ctx->major)
737+ ssh_gssapi_error(ctx);
738+
739+ return(ctx->major);
740+}
741+
742+OM_uint32
743 ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
744 {
745+ if (ctx == NULL)
746+ return -1;
747+
748 if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
749 GSS_C_QOP_DEFAULT, buffer, hash)))
750 ssh_gssapi_error(ctx);
751@@ -236,6 +425,19 @@ ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
752 return (ctx->major);
753 }
754
755+/* Priviledged when used by server */
756+OM_uint32
757+ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
758+{
759+ if (ctx == NULL)
760+ return -1;
761+
762+ ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
763+ gssbuf, gssmic, NULL);
764+
765+ return (ctx->major);
766+}
767+
768 void
769 ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
770 const char *context)
771@@ -249,11 +451,16 @@ ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
772 }
773
774 int
775-ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
776+ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host,
777+ const char *client)
778 {
779 gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
780 OM_uint32 major, minor;
781 gss_OID_desc spnego_oid = {6, (void *)"\x2B\x06\x01\x05\x05\x02"};
782+ Gssctxt *intctx = NULL;
783+
784+ if (ctx == NULL)
785+ ctx = &intctx;
786
787 /* RFC 4462 says we MUST NOT do SPNEGO */
788 if (oid->length == spnego_oid.length &&
789@@ -263,6 +470,10 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
790 ssh_gssapi_build_ctx(ctx);
791 ssh_gssapi_set_oid(*ctx, oid);
792 major = ssh_gssapi_import_name(*ctx, host);
793+
794+ if (!GSS_ERROR(major) && client)
795+ major = ssh_gssapi_client_identity(*ctx, client);
796+
797 if (!GSS_ERROR(major)) {
798 major = ssh_gssapi_init_ctx(*ctx, 0, GSS_C_NO_BUFFER, &token,
799 NULL);
800@@ -272,10 +483,66 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
801 GSS_C_NO_BUFFER);
802 }
803
804- if (GSS_ERROR(major))
805+ if (GSS_ERROR(major) || intctx != NULL)
806 ssh_gssapi_delete_ctx(ctx);
807
808 return (!GSS_ERROR(major));
809 }
810
811+int
812+ssh_gssapi_credentials_updated(Gssctxt *ctxt) {
813+ static gss_name_t saved_name = GSS_C_NO_NAME;
814+ static OM_uint32 saved_lifetime = 0;
815+ static gss_OID saved_mech = GSS_C_NO_OID;
816+ static gss_name_t name;
817+ static OM_uint32 last_call = 0;
818+ OM_uint32 lifetime, now, major, minor;
819+ int equal;
820+
821+ now = time(NULL);
822+
823+ if (ctxt) {
824+ debug("Rekey has happened - updating saved versions");
825+
826+ if (saved_name != GSS_C_NO_NAME)
827+ gss_release_name(&minor, &saved_name);
828+
829+ major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
830+ &saved_name, &saved_lifetime, NULL, NULL);
831+
832+ if (!GSS_ERROR(major)) {
833+ saved_mech = ctxt->oid;
834+ saved_lifetime+= now;
835+ } else {
836+ /* Handle the error */
837+ }
838+ return 0;
839+ }
840+
841+ if (now - last_call < 10)
842+ return 0;
843+
844+ last_call = now;
845+
846+ if (saved_mech == GSS_C_NO_OID)
847+ return 0;
848+
849+ major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
850+ &name, &lifetime, NULL, NULL);
851+ if (major == GSS_S_CREDENTIALS_EXPIRED)
852+ return 0;
853+ else if (GSS_ERROR(major))
854+ return 0;
855+
856+ major = gss_compare_name(&minor, saved_name, name, &equal);
857+ gss_release_name(&minor, &name);
858+ if (GSS_ERROR(major))
859+ return 0;
860+
861+ if (equal && (saved_lifetime < lifetime + now - 10))
862+ return 1;
863+
864+ return 0;
865+}
866+
867 #endif /* GSSAPI */
868diff --git a/gss-serv-krb5.c b/gss-serv-krb5.c
869index 759fa10..e678a27 100644
870--- a/gss-serv-krb5.c
871+++ b/gss-serv-krb5.c
872@@ -1,7 +1,7 @@
873 /* $OpenBSD: gss-serv-krb5.c,v 1.8 2013/07/20 01:55:13 djm Exp $ */
874
875 /*
876- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
877+ * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
878 *
879 * Redistribution and use in source and binary forms, with or without
880 * modification, are permitted provided that the following conditions
881@@ -120,8 +120,8 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
882 krb5_error_code problem;
883 krb5_principal princ;
884 OM_uint32 maj_status, min_status;
885- int len;
886 const char *errmsg;
887+ const char *new_ccname;
888
889 if (client->creds == NULL) {
890 debug("No credentials stored");
891@@ -180,11 +180,16 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
892 return;
893 }
894
895- client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache));
896+ new_ccname = krb5_cc_get_name(krb_context, ccache);
897+
898 client->store.envvar = "KRB5CCNAME";
899- len = strlen(client->store.filename) + 6;
900- client->store.envval = xmalloc(len);
901- snprintf(client->store.envval, len, "FILE:%s", client->store.filename);
902+#ifdef USE_CCAPI
903+ xasprintf(&client->store.envval, "API:%s", new_ccname);
904+ client->store.filename = NULL;
905+#else
906+ xasprintf(&client->store.envval, "FILE:%s", new_ccname);
907+ client->store.filename = xstrdup(new_ccname);
908+#endif
909
910 #ifdef USE_PAM
911 if (options.use_pam)
912@@ -196,6 +201,71 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
913 return;
914 }
915
916+int
917+ssh_gssapi_krb5_updatecreds(ssh_gssapi_ccache *store,
918+ ssh_gssapi_client *client)
919+{
920+ krb5_ccache ccache = NULL;
921+ krb5_principal principal = NULL;
922+ char *name = NULL;
923+ krb5_error_code problem;
924+ OM_uint32 maj_status, min_status;
925+
926+ if ((problem = krb5_cc_resolve(krb_context, store->envval, &ccache))) {
927+ logit("krb5_cc_resolve(): %.100s",
928+ krb5_get_err_text(krb_context, problem));
929+ return 0;
930+ }
931+
932+ /* Find out who the principal in this cache is */
933+ if ((problem = krb5_cc_get_principal(krb_context, ccache,
934+ &principal))) {
935+ logit("krb5_cc_get_principal(): %.100s",
936+ krb5_get_err_text(krb_context, problem));
937+ krb5_cc_close(krb_context, ccache);
938+ return 0;
939+ }
940+
941+ if ((problem = krb5_unparse_name(krb_context, principal, &name))) {
942+ logit("krb5_unparse_name(): %.100s",
943+ krb5_get_err_text(krb_context, problem));
944+ krb5_free_principal(krb_context, principal);
945+ krb5_cc_close(krb_context, ccache);
946+ return 0;
947+ }
948+
949+
950+ if (strcmp(name,client->exportedname.value)!=0) {
951+ debug("Name in local credentials cache differs. Not storing");
952+ krb5_free_principal(krb_context, principal);
953+ krb5_cc_close(krb_context, ccache);
954+ krb5_free_unparsed_name(krb_context, name);
955+ return 0;
956+ }
957+ krb5_free_unparsed_name(krb_context, name);
958+
959+ /* Name matches, so lets get on with it! */
960+
961+ if ((problem = krb5_cc_initialize(krb_context, ccache, principal))) {
962+ logit("krb5_cc_initialize(): %.100s",
963+ krb5_get_err_text(krb_context, problem));
964+ krb5_free_principal(krb_context, principal);
965+ krb5_cc_close(krb_context, ccache);
966+ return 0;
967+ }
968+
969+ krb5_free_principal(krb_context, principal);
970+
971+ if ((maj_status = gss_krb5_copy_ccache(&min_status, client->creds,
972+ ccache))) {
973+ logit("gss_krb5_copy_ccache() failed. Sorry!");
974+ krb5_cc_close(krb_context, ccache);
975+ return 0;
976+ }
977+
978+ return 1;
979+}
980+
981 ssh_gssapi_mech gssapi_kerberos_mech = {
982 "toWM5Slw5Ew8Mqkay+al2g==",
983 "Kerberos",
984@@ -203,7 +273,8 @@ ssh_gssapi_mech gssapi_kerberos_mech = {
985 NULL,
986 &ssh_gssapi_krb5_userok,
987 NULL,
988- &ssh_gssapi_krb5_storecreds
989+ &ssh_gssapi_krb5_storecreds,
990+ &ssh_gssapi_krb5_updatecreds
991 };
992
993 #endif /* KRB5 */
994diff --git a/gss-serv.c b/gss-serv.c
995index 95348e2..feb1ed7 100644
996--- a/gss-serv.c
997+++ b/gss-serv.c
998@@ -1,7 +1,7 @@
999 /* $OpenBSD: gss-serv.c,v 1.24 2013/07/20 01:55:13 djm Exp $ */
1000
1001 /*
1002- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
1003+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
1004 *
1005 * Redistribution and use in source and binary forms, with or without
1006 * modification, are permitted provided that the following conditions
1007@@ -45,15 +45,21 @@
1008 #include "channels.h"
1009 #include "session.h"
1010 #include "misc.h"
1011+#include "servconf.h"
1012+#include "uidswap.h"
1013
1014 #include "ssh-gss.h"
1015+#include "monitor_wrap.h"
1016+
1017+extern ServerOptions options;
1018
1019 static ssh_gssapi_client gssapi_client =
1020 { GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER,
1021- GSS_C_NO_CREDENTIAL, NULL, {NULL, NULL, NULL, NULL}};
1022+ GSS_C_NO_CREDENTIAL, GSS_C_NO_NAME, NULL,
1023+ {NULL, NULL, NULL, NULL, NULL}, 0, 0};
1024
1025 ssh_gssapi_mech gssapi_null_mech =
1026- { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL};
1027+ { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL, NULL};
1028
1029 #ifdef KRB5
1030 extern ssh_gssapi_mech gssapi_kerberos_mech;
1031@@ -81,25 +87,32 @@ ssh_gssapi_acquire_cred(Gssctxt *ctx)
1032 char lname[MAXHOSTNAMELEN];
1033 gss_OID_set oidset;
1034
1035- gss_create_empty_oid_set(&status, &oidset);
1036- gss_add_oid_set_member(&status, ctx->oid, &oidset);
1037+ if (options.gss_strict_acceptor) {
1038+ gss_create_empty_oid_set(&status, &oidset);
1039+ gss_add_oid_set_member(&status, ctx->oid, &oidset);
1040
1041- if (gethostname(lname, MAXHOSTNAMELEN)) {
1042- gss_release_oid_set(&status, &oidset);
1043- return (-1);
1044- }
1045+ if (gethostname(lname, MAXHOSTNAMELEN)) {
1046+ gss_release_oid_set(&status, &oidset);
1047+ return (-1);
1048+ }
1049+
1050+ if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname))) {
1051+ gss_release_oid_set(&status, &oidset);
1052+ return (ctx->major);
1053+ }
1054+
1055+ if ((ctx->major = gss_acquire_cred(&ctx->minor,
1056+ ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds,
1057+ NULL, NULL)))
1058+ ssh_gssapi_error(ctx);
1059
1060- if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname))) {
1061 gss_release_oid_set(&status, &oidset);
1062 return (ctx->major);
1063+ } else {
1064+ ctx->name = GSS_C_NO_NAME;
1065+ ctx->creds = GSS_C_NO_CREDENTIAL;
1066 }
1067-
1068- if ((ctx->major = gss_acquire_cred(&ctx->minor,
1069- ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds, NULL, NULL)))
1070- ssh_gssapi_error(ctx);
1071-
1072- gss_release_oid_set(&status, &oidset);
1073- return (ctx->major);
1074+ return GSS_S_COMPLETE;
1075 }
1076
1077 /* Privileged */
1078@@ -114,6 +127,29 @@ ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
1079 }
1080
1081 /* Unprivileged */
1082+char *
1083+ssh_gssapi_server_mechanisms(void) {
1084+ gss_OID_set supported;
1085+
1086+ ssh_gssapi_supported_oids(&supported);
1087+ return (ssh_gssapi_kex_mechs(supported, &ssh_gssapi_server_check_mech,
1088+ NULL, NULL));
1089+}
1090+
1091+/* Unprivileged */
1092+int
1093+ssh_gssapi_server_check_mech(Gssctxt **dum, gss_OID oid, const char *data,
1094+ const char *dummy) {
1095+ Gssctxt *ctx = NULL;
1096+ int res;
1097+
1098+ res = !GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctx, oid)));
1099+ ssh_gssapi_delete_ctx(&ctx);
1100+
1101+ return (res);
1102+}
1103+
1104+/* Unprivileged */
1105 void
1106 ssh_gssapi_supported_oids(gss_OID_set *oidset)
1107 {
1108@@ -123,7 +159,9 @@ ssh_gssapi_supported_oids(gss_OID_set *oidset)
1109 gss_OID_set supported;
1110
1111 gss_create_empty_oid_set(&min_status, oidset);
1112- gss_indicate_mechs(&min_status, &supported);
1113+
1114+ if (GSS_ERROR(gss_indicate_mechs(&min_status, &supported)))
1115+ return;
1116
1117 while (supported_mechs[i]->name != NULL) {
1118 if (GSS_ERROR(gss_test_oid_set_member(&min_status,
1119@@ -249,8 +287,48 @@ OM_uint32
1120 ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
1121 {
1122 int i = 0;
1123+ int equal = 0;
1124+ gss_name_t new_name = GSS_C_NO_NAME;
1125+ gss_buffer_desc ename = GSS_C_EMPTY_BUFFER;
1126+
1127+ if (options.gss_store_rekey && client->used && ctx->client_creds) {
1128+ if (client->mech->oid.length != ctx->oid->length ||
1129+ (memcmp(client->mech->oid.elements,
1130+ ctx->oid->elements, ctx->oid->length) !=0)) {
1131+ debug("Rekeyed credentials have different mechanism");
1132+ return GSS_S_COMPLETE;
1133+ }
1134+
1135+ if ((ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
1136+ ctx->client_creds, ctx->oid, &new_name,
1137+ NULL, NULL, NULL))) {
1138+ ssh_gssapi_error(ctx);
1139+ return (ctx->major);
1140+ }
1141+
1142+ ctx->major = gss_compare_name(&ctx->minor, client->name,
1143+ new_name, &equal);
1144
1145- gss_buffer_desc ename;
1146+ if (GSS_ERROR(ctx->major)) {
1147+ ssh_gssapi_error(ctx);
1148+ return (ctx->major);
1149+ }
1150+
1151+ if (!equal) {
1152+ debug("Rekeyed credentials have different name");
1153+ return GSS_S_COMPLETE;
1154+ }
1155+
1156+ debug("Marking rekeyed credentials for export");
1157+
1158+ gss_release_name(&ctx->minor, &client->name);
1159+ gss_release_cred(&ctx->minor, &client->creds);
1160+ client->name = new_name;
1161+ client->creds = ctx->client_creds;
1162+ ctx->client_creds = GSS_C_NO_CREDENTIAL;
1163+ client->updated = 1;
1164+ return GSS_S_COMPLETE;
1165+ }
1166
1167 client->mech = NULL;
1168
1169@@ -265,6 +343,13 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
1170 if (client->mech == NULL)
1171 return GSS_S_FAILURE;
1172
1173+ if (ctx->client_creds &&
1174+ (ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
1175+ ctx->client_creds, ctx->oid, &client->name, NULL, NULL, NULL))) {
1176+ ssh_gssapi_error(ctx);
1177+ return (ctx->major);
1178+ }
1179+
1180 if ((ctx->major = gss_display_name(&ctx->minor, ctx->client,
1181 &client->displayname, NULL))) {
1182 ssh_gssapi_error(ctx);
1183@@ -282,6 +367,8 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
1184 return (ctx->major);
1185 }
1186
1187+ gss_release_buffer(&ctx->minor, &ename);
1188+
1189 /* We can't copy this structure, so we just move the pointer to it */
1190 client->creds = ctx->client_creds;
1191 ctx->client_creds = GSS_C_NO_CREDENTIAL;
1192@@ -329,7 +416,7 @@ ssh_gssapi_do_child(char ***envp, u_int *envsizep)
1193
1194 /* Privileged */
1195 int
1196-ssh_gssapi_userok(char *user)
1197+ssh_gssapi_userok(char *user, struct passwd *pw)
1198 {
1199 OM_uint32 lmin;
1200
1201@@ -339,9 +426,11 @@ ssh_gssapi_userok(char *user)
1202 return 0;
1203 }
1204 if (gssapi_client.mech && gssapi_client.mech->userok)
1205- if ((*gssapi_client.mech->userok)(&gssapi_client, user))
1206+ if ((*gssapi_client.mech->userok)(&gssapi_client, user)) {
1207+ gssapi_client.used = 1;
1208+ gssapi_client.store.owner = pw;
1209 return 1;
1210- else {
1211+ } else {
1212 /* Destroy delegated credentials if userok fails */
1213 gss_release_buffer(&lmin, &gssapi_client.displayname);
1214 gss_release_buffer(&lmin, &gssapi_client.exportedname);
1215@@ -354,14 +443,90 @@ ssh_gssapi_userok(char *user)
1216 return (0);
1217 }
1218
1219-/* Privileged */
1220-OM_uint32
1221-ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1222+/* These bits are only used for rekeying. The unpriviledged child is running
1223+ * as the user, the monitor is root.
1224+ *
1225+ * In the child, we want to :
1226+ * *) Ask the monitor to store our credentials into the store we specify
1227+ * *) If it succeeds, maybe do a PAM update
1228+ */
1229+
1230+/* Stuff for PAM */
1231+
1232+#ifdef USE_PAM
1233+static int ssh_gssapi_simple_conv(int n, const struct pam_message **msg,
1234+ struct pam_response **resp, void *data)
1235 {
1236- ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
1237- gssbuf, gssmic, NULL);
1238+ return (PAM_CONV_ERR);
1239+}
1240+#endif
1241
1242- return (ctx->major);
1243+void
1244+ssh_gssapi_rekey_creds(void) {
1245+ int ok;
1246+ int ret;
1247+#ifdef USE_PAM
1248+ pam_handle_t *pamh = NULL;
1249+ struct pam_conv pamconv = {ssh_gssapi_simple_conv, NULL};
1250+ char *envstr;
1251+#endif
1252+
1253+ if (gssapi_client.store.filename == NULL &&
1254+ gssapi_client.store.envval == NULL &&
1255+ gssapi_client.store.envvar == NULL)
1256+ return;
1257+
1258+ ok = PRIVSEP(ssh_gssapi_update_creds(&gssapi_client.store));
1259+
1260+ if (!ok)
1261+ return;
1262+
1263+ debug("Rekeyed credentials stored successfully");
1264+
1265+ /* Actually managing to play with the ssh pam stack from here will
1266+ * be next to impossible. In any case, we may want different options
1267+ * for rekeying. So, use our own :)
1268+ */
1269+#ifdef USE_PAM
1270+ if (!use_privsep) {
1271+ debug("Not even going to try and do PAM with privsep disabled");
1272+ return;
1273+ }
1274+
1275+ ret = pam_start("sshd-rekey", gssapi_client.store.owner->pw_name,
1276+ &pamconv, &pamh);
1277+ if (ret)
1278+ return;
1279+
1280+ xasprintf(&envstr, "%s=%s", gssapi_client.store.envvar,
1281+ gssapi_client.store.envval);
1282+
1283+ ret = pam_putenv(pamh, envstr);
1284+ if (!ret)
1285+ pam_setcred(pamh, PAM_REINITIALIZE_CRED);
1286+ pam_end(pamh, PAM_SUCCESS);
1287+#endif
1288+}
1289+
1290+int
1291+ssh_gssapi_update_creds(ssh_gssapi_ccache *store) {
1292+ int ok = 0;
1293+
1294+ /* Check we've got credentials to store */
1295+ if (!gssapi_client.updated)
1296+ return 0;
1297+
1298+ gssapi_client.updated = 0;
1299+
1300+ temporarily_use_uid(gssapi_client.store.owner);
1301+ if (gssapi_client.mech && gssapi_client.mech->updatecreds)
1302+ ok = (*gssapi_client.mech->updatecreds)(store, &gssapi_client);
1303+ else
1304+ debug("No update function for this mechanism");
1305+
1306+ restore_uid();
1307+
1308+ return ok;
1309 }
1310
1311 #endif
1312diff --git a/kex.c b/kex.c
1313index 616484b..49d0fc8 100644
1314--- a/kex.c
1315+++ b/kex.c
1316@@ -51,6 +51,10 @@
1317 #include "roaming.h"
1318 #include "digest.h"
1319
1320+#ifdef GSSAPI
1321+#include "ssh-gss.h"
1322+#endif
1323+
1324 #if OPENSSL_VERSION_NUMBER >= 0x00907000L
1325 # if defined(HAVE_EVP_SHA256)
1326 # define evp_ssh_sha256 EVP_sha256
1327@@ -92,6 +96,14 @@ static const struct kexalg kexalgs[] = {
1328 #endif
1329 { NULL, -1, -1, -1},
1330 };
1331+static const struct kexalg kexalg_prefixes[] = {
1332+#ifdef GSSAPI
1333+ { KEX_GSS_GEX_SHA1_ID, KEX_GSS_GEX_SHA1, 0, SSH_DIGEST_SHA1 },
1334+ { KEX_GSS_GRP1_SHA1_ID, KEX_GSS_GRP1_SHA1, 0, SSH_DIGEST_SHA1 },
1335+ { KEX_GSS_GRP14_SHA1_ID, KEX_GSS_GRP14_SHA1, 0, SSH_DIGEST_SHA1 },
1336+#endif
1337+ { NULL, -1, -1, -1 },
1338+};
1339
1340 char *
1341 kex_alg_list(char sep)
1342@@ -120,6 +132,10 @@ kex_alg_by_name(const char *name)
1343 if (strcmp(k->name, name) == 0)
1344 return k;
1345 }
1346+ for (k = kexalg_prefixes; k->name != NULL; k++) {
1347+ if (strncmp(k->name, name, strlen(k->name)) == 0)
1348+ return k;
1349+ }
1350 return NULL;
1351 }
1352
1353diff --git a/kex.h b/kex.h
1354index 1aa3ec2..8fbcb2b 100644
1355--- a/kex.h
1356+++ b/kex.h
1357@@ -76,6 +76,9 @@ enum kex_exchange {
1358 KEX_DH_GEX_SHA256,
1359 KEX_ECDH_SHA2,
1360 KEX_C25519_SHA256,
1361+ KEX_GSS_GRP1_SHA1,
1362+ KEX_GSS_GRP14_SHA1,
1363+ KEX_GSS_GEX_SHA1,
1364 KEX_MAX
1365 };
1366
1367@@ -136,6 +139,12 @@ struct Kex {
1368 int flags;
1369 int hash_alg;
1370 int ec_nid;
1371+#ifdef GSSAPI
1372+ int gss_deleg_creds;
1373+ int gss_trust_dns;
1374+ char *gss_host;
1375+ char *gss_client;
1376+#endif
1377 char *client_version_string;
1378 char *server_version_string;
1379 int (*verify_host_key)(Key *);
1380@@ -168,6 +177,11 @@ void kexecdh_server(Kex *);
1381 void kexc25519_client(Kex *);
1382 void kexc25519_server(Kex *);
1383
1384+#ifdef GSSAPI
1385+void kexgss_client(Kex *);
1386+void kexgss_server(Kex *);
1387+#endif
1388+
1389 void
1390 kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
1391 BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
1392diff --git a/kexgssc.c b/kexgssc.c
1393new file mode 100644
1394index 0000000..92a31c5
1395--- /dev/null
1396+++ b/kexgssc.c
1397@@ -0,0 +1,332 @@
1398+/*
1399+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
1400+ *
1401+ * Redistribution and use in source and binary forms, with or without
1402+ * modification, are permitted provided that the following conditions
1403+ * are met:
1404+ * 1. Redistributions of source code must retain the above copyright
1405+ * notice, this list of conditions and the following disclaimer.
1406+ * 2. Redistributions in binary form must reproduce the above copyright
1407+ * notice, this list of conditions and the following disclaimer in the
1408+ * documentation and/or other materials provided with the distribution.
1409+ *
1410+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
1411+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1412+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
1413+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
1414+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
1415+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1416+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1417+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1418+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1419+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1420+ */
1421+
1422+#include "includes.h"
1423+
1424+#ifdef GSSAPI
1425+
1426+#include "includes.h"
1427+
1428+#include <openssl/crypto.h>
1429+#include <openssl/bn.h>
1430+
1431+#include <string.h>
1432+
1433+#include "xmalloc.h"
1434+#include "buffer.h"
1435+#include "ssh2.h"
1436+#include "key.h"
1437+#include "cipher.h"
1438+#include "kex.h"
1439+#include "log.h"
1440+#include "packet.h"
1441+#include "dh.h"
1442+
1443+#include "ssh-gss.h"
1444+
1445+void
1446+kexgss_client(Kex *kex) {
1447+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1448+ gss_buffer_desc recv_tok, gssbuf, msg_tok, *token_ptr;
1449+ Gssctxt *ctxt;
1450+ OM_uint32 maj_status, min_status, ret_flags;
1451+ u_int klen, kout, slen = 0, hashlen, strlen;
1452+ DH *dh;
1453+ BIGNUM *dh_server_pub = NULL;
1454+ BIGNUM *shared_secret = NULL;
1455+ BIGNUM *p = NULL;
1456+ BIGNUM *g = NULL;
1457+ u_char *kbuf, *hash;
1458+ u_char *serverhostkey = NULL;
1459+ u_char *empty = "";
1460+ char *msg;
1461+ int type = 0;
1462+ int first = 1;
1463+ int nbits = 0, min = DH_GRP_MIN, max = DH_GRP_MAX;
1464+
1465+ /* Initialise our GSSAPI world */
1466+ ssh_gssapi_build_ctx(&ctxt);
1467+ if (ssh_gssapi_id_kex(ctxt, kex->name, kex->kex_type)
1468+ == GSS_C_NO_OID)
1469+ fatal("Couldn't identify host exchange");
1470+
1471+ if (ssh_gssapi_import_name(ctxt, kex->gss_host))
1472+ fatal("Couldn't import hostname");
1473+
1474+ if (kex->gss_client &&
1475+ ssh_gssapi_client_identity(ctxt, kex->gss_client))
1476+ fatal("Couldn't acquire client credentials");
1477+
1478+ switch (kex->kex_type) {
1479+ case KEX_GSS_GRP1_SHA1:
1480+ dh = dh_new_group1();
1481+ break;
1482+ case KEX_GSS_GRP14_SHA1:
1483+ dh = dh_new_group14();
1484+ break;
1485+ case KEX_GSS_GEX_SHA1:
1486+ debug("Doing group exchange\n");
1487+ nbits = dh_estimate(kex->we_need * 8);
1488+ packet_start(SSH2_MSG_KEXGSS_GROUPREQ);
1489+ packet_put_int(min);
1490+ packet_put_int(nbits);
1491+ packet_put_int(max);
1492+
1493+ packet_send();
1494+
1495+ packet_read_expect(SSH2_MSG_KEXGSS_GROUP);
1496+
1497+ if ((p = BN_new()) == NULL)
1498+ fatal("BN_new() failed");
1499+ packet_get_bignum2(p);
1500+ if ((g = BN_new()) == NULL)
1501+ fatal("BN_new() failed");
1502+ packet_get_bignum2(g);
1503+ packet_check_eom();
1504+
1505+ if (BN_num_bits(p) < min || BN_num_bits(p) > max)
1506+ fatal("GSSGRP_GEX group out of range: %d !< %d !< %d",
1507+ min, BN_num_bits(p), max);
1508+
1509+ dh = dh_new_group(g, p);
1510+ break;
1511+ default:
1512+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
1513+ }
1514+
1515+ /* Step 1 - e is dh->pub_key */
1516+ dh_gen_key(dh, kex->we_need * 8);
1517+
1518+ /* This is f, we initialise it now to make life easier */
1519+ dh_server_pub = BN_new();
1520+ if (dh_server_pub == NULL)
1521+ fatal("dh_server_pub == NULL");
1522+
1523+ token_ptr = GSS_C_NO_BUFFER;
1524+
1525+ do {
1526+ debug("Calling gss_init_sec_context");
1527+
1528+ maj_status = ssh_gssapi_init_ctx(ctxt,
1529+ kex->gss_deleg_creds, token_ptr, &send_tok,
1530+ &ret_flags);
1531+
1532+ if (GSS_ERROR(maj_status)) {
1533+ if (send_tok.length != 0) {
1534+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1535+ packet_put_string(send_tok.value,
1536+ send_tok.length);
1537+ }
1538+ fatal("gss_init_context failed");
1539+ }
1540+
1541+ /* If we've got an old receive buffer get rid of it */
1542+ if (token_ptr != GSS_C_NO_BUFFER)
1543+ free(recv_tok.value);
1544+
1545+ if (maj_status == GSS_S_COMPLETE) {
1546+ /* If mutual state flag is not true, kex fails */
1547+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
1548+ fatal("Mutual authentication failed");
1549+
1550+ /* If integ avail flag is not true kex fails */
1551+ if (!(ret_flags & GSS_C_INTEG_FLAG))
1552+ fatal("Integrity check failed");
1553+ }
1554+
1555+ /*
1556+ * If we have data to send, then the last message that we
1557+ * received cannot have been a 'complete'.
1558+ */
1559+ if (send_tok.length != 0) {
1560+ if (first) {
1561+ packet_start(SSH2_MSG_KEXGSS_INIT);
1562+ packet_put_string(send_tok.value,
1563+ send_tok.length);
1564+ packet_put_bignum2(dh->pub_key);
1565+ first = 0;
1566+ } else {
1567+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1568+ packet_put_string(send_tok.value,
1569+ send_tok.length);
1570+ }
1571+ packet_send();
1572+ gss_release_buffer(&min_status, &send_tok);
1573+
1574+ /* If we've sent them data, they should reply */
1575+ do {
1576+ type = packet_read();
1577+ if (type == SSH2_MSG_KEXGSS_HOSTKEY) {
1578+ debug("Received KEXGSS_HOSTKEY");
1579+ if (serverhostkey)
1580+ fatal("Server host key received more than once");
1581+ serverhostkey =
1582+ packet_get_string(&slen);
1583+ }
1584+ } while (type == SSH2_MSG_KEXGSS_HOSTKEY);
1585+
1586+ switch (type) {
1587+ case SSH2_MSG_KEXGSS_CONTINUE:
1588+ debug("Received GSSAPI_CONTINUE");
1589+ if (maj_status == GSS_S_COMPLETE)
1590+ fatal("GSSAPI Continue received from server when complete");
1591+ recv_tok.value = packet_get_string(&strlen);
1592+ recv_tok.length = strlen;
1593+ break;
1594+ case SSH2_MSG_KEXGSS_COMPLETE:
1595+ debug("Received GSSAPI_COMPLETE");
1596+ packet_get_bignum2(dh_server_pub);
1597+ msg_tok.value = packet_get_string(&strlen);
1598+ msg_tok.length = strlen;
1599+
1600+ /* Is there a token included? */
1601+ if (packet_get_char()) {
1602+ recv_tok.value=
1603+ packet_get_string(&strlen);
1604+ recv_tok.length = strlen;
1605+ /* If we're already complete - protocol error */
1606+ if (maj_status == GSS_S_COMPLETE)
1607+ packet_disconnect("Protocol error: received token when complete");
1608+ } else {
1609+ /* No token included */
1610+ if (maj_status != GSS_S_COMPLETE)
1611+ packet_disconnect("Protocol error: did not receive final token");
1612+ }
1613+ break;
1614+ case SSH2_MSG_KEXGSS_ERROR:
1615+ debug("Received Error");
1616+ maj_status = packet_get_int();
1617+ min_status = packet_get_int();
1618+ msg = packet_get_string(NULL);
1619+ (void) packet_get_string_ptr(NULL);
1620+ fatal("GSSAPI Error: \n%.400s",msg);
1621+ default:
1622+ packet_disconnect("Protocol error: didn't expect packet type %d",
1623+ type);
1624+ }
1625+ token_ptr = &recv_tok;
1626+ } else {
1627+ /* No data, and not complete */
1628+ if (maj_status != GSS_S_COMPLETE)
1629+ fatal("Not complete, and no token output");
1630+ }
1631+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
1632+
1633+ /*
1634+ * We _must_ have received a COMPLETE message in reply from the
1635+ * server, which will have set dh_server_pub and msg_tok
1636+ */
1637+
1638+ if (type != SSH2_MSG_KEXGSS_COMPLETE)
1639+ fatal("Didn't receive a SSH2_MSG_KEXGSS_COMPLETE when I expected it");
1640+
1641+ /* Check f in range [1, p-1] */
1642+ if (!dh_pub_is_valid(dh, dh_server_pub))
1643+ packet_disconnect("bad server public DH value");
1644+
1645+ /* compute K=f^x mod p */
1646+ klen = DH_size(dh);
1647+ kbuf = xmalloc(klen);
1648+ kout = DH_compute_key(kbuf, dh_server_pub, dh);
1649+ if (kout < 0)
1650+ fatal("DH_compute_key: failed");
1651+
1652+ shared_secret = BN_new();
1653+ if (shared_secret == NULL)
1654+ fatal("kexgss_client: BN_new failed");
1655+
1656+ if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
1657+ fatal("kexdh_client: BN_bin2bn failed");
1658+
1659+ memset(kbuf, 0, klen);
1660+ free(kbuf);
1661+
1662+ switch (kex->kex_type) {
1663+ case KEX_GSS_GRP1_SHA1:
1664+ case KEX_GSS_GRP14_SHA1:
1665+ kex_dh_hash( kex->client_version_string,
1666+ kex->server_version_string,
1667+ buffer_ptr(&kex->my), buffer_len(&kex->my),
1668+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
1669+ (serverhostkey ? serverhostkey : empty), slen,
1670+ dh->pub_key, /* e */
1671+ dh_server_pub, /* f */
1672+ shared_secret, /* K */
1673+ &hash, &hashlen
1674+ );
1675+ break;
1676+ case KEX_GSS_GEX_SHA1:
1677+ kexgex_hash(
1678+ kex->hash_alg,
1679+ kex->client_version_string,
1680+ kex->server_version_string,
1681+ buffer_ptr(&kex->my), buffer_len(&kex->my),
1682+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
1683+ (serverhostkey ? serverhostkey : empty), slen,
1684+ min, nbits, max,
1685+ dh->p, dh->g,
1686+ dh->pub_key,
1687+ dh_server_pub,
1688+ shared_secret,
1689+ &hash, &hashlen
1690+ );
1691+ break;
1692+ default:
1693+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
1694+ }
1695+
1696+ gssbuf.value = hash;
1697+ gssbuf.length = hashlen;
1698+
1699+ /* Verify that the hash matches the MIC we just got. */
1700+ if (GSS_ERROR(ssh_gssapi_checkmic(ctxt, &gssbuf, &msg_tok)))
1701+ packet_disconnect("Hash's MIC didn't verify");
1702+
1703+ free(msg_tok.value);
1704+
1705+ DH_free(dh);
1706+ free(serverhostkey);
1707+ BN_clear_free(dh_server_pub);
1708+
1709+ /* save session id */
1710+ if (kex->session_id == NULL) {
1711+ kex->session_id_len = hashlen;
1712+ kex->session_id = xmalloc(kex->session_id_len);
1713+ memcpy(kex->session_id, hash, kex->session_id_len);
1714+ }
1715+
1716+ if (kex->gss_deleg_creds)
1717+ ssh_gssapi_credentials_updated(ctxt);
1718+
1719+ if (gss_kex_context == NULL)
1720+ gss_kex_context = ctxt;
1721+ else
1722+ ssh_gssapi_delete_ctx(&ctxt);
1723+
1724+ kex_derive_keys_bn(kex, hash, hashlen, shared_secret);
1725+ BN_clear_free(shared_secret);
1726+ kex_finish(kex);
1727+}
1728+
1729+#endif /* GSSAPI */
1730diff --git a/kexgsss.c b/kexgsss.c
1731new file mode 100644
1732index 0000000..8095259
1733--- /dev/null
1734+++ b/kexgsss.c
1735@@ -0,0 +1,289 @@
1736+/*
1737+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
1738+ *
1739+ * Redistribution and use in source and binary forms, with or without
1740+ * modification, are permitted provided that the following conditions
1741+ * are met:
1742+ * 1. Redistributions of source code must retain the above copyright
1743+ * notice, this list of conditions and the following disclaimer.
1744+ * 2. Redistributions in binary form must reproduce the above copyright
1745+ * notice, this list of conditions and the following disclaimer in the
1746+ * documentation and/or other materials provided with the distribution.
1747+ *
1748+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
1749+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1750+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
1751+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
1752+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
1753+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1754+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1755+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1756+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1757+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1758+ */
1759+
1760+#include "includes.h"
1761+
1762+#ifdef GSSAPI
1763+
1764+#include <string.h>
1765+
1766+#include <openssl/crypto.h>
1767+#include <openssl/bn.h>
1768+
1769+#include "xmalloc.h"
1770+#include "buffer.h"
1771+#include "ssh2.h"
1772+#include "key.h"
1773+#include "cipher.h"
1774+#include "kex.h"
1775+#include "log.h"
1776+#include "packet.h"
1777+#include "dh.h"
1778+#include "ssh-gss.h"
1779+#include "monitor_wrap.h"
1780+#include "servconf.h"
1781+
1782+extern ServerOptions options;
1783+
1784+void
1785+kexgss_server(Kex *kex)
1786+{
1787+ OM_uint32 maj_status, min_status;
1788+
1789+ /*
1790+ * Some GSSAPI implementations use the input value of ret_flags (an
1791+ * output variable) as a means of triggering mechanism specific
1792+ * features. Initializing it to zero avoids inadvertently
1793+ * activating this non-standard behaviour.
1794+ */
1795+
1796+ OM_uint32 ret_flags = 0;
1797+ gss_buffer_desc gssbuf, recv_tok, msg_tok;
1798+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1799+ Gssctxt *ctxt = NULL;
1800+ u_int slen, klen, kout, hashlen;
1801+ u_char *kbuf, *hash;
1802+ DH *dh;
1803+ int min = -1, max = -1, nbits = -1;
1804+ BIGNUM *shared_secret = NULL;
1805+ BIGNUM *dh_client_pub = NULL;
1806+ int type = 0;
1807+ gss_OID oid;
1808+ char *mechs;
1809+
1810+ /* Initialise GSSAPI */
1811+
1812+ /* If we're rekeying, privsep means that some of the private structures
1813+ * in the GSSAPI code are no longer available. This kludges them back
1814+ * into life
1815+ */
1816+ if (!ssh_gssapi_oid_table_ok()) {
1817+ mechs = ssh_gssapi_server_mechanisms();
1818+ free(mechs);
1819+ }
1820+
1821+ debug2("%s: Identifying %s", __func__, kex->name);
1822+ oid = ssh_gssapi_id_kex(NULL, kex->name, kex->kex_type);
1823+ if (oid == GSS_C_NO_OID)
1824+ fatal("Unknown gssapi mechanism");
1825+
1826+ debug2("%s: Acquiring credentials", __func__);
1827+
1828+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctxt, oid))))
1829+ fatal("Unable to acquire credentials for the server");
1830+
1831+ switch (kex->kex_type) {
1832+ case KEX_GSS_GRP1_SHA1:
1833+ dh = dh_new_group1();
1834+ break;
1835+ case KEX_GSS_GRP14_SHA1:
1836+ dh = dh_new_group14();
1837+ break;
1838+ case KEX_GSS_GEX_SHA1:
1839+ debug("Doing group exchange");
1840+ packet_read_expect(SSH2_MSG_KEXGSS_GROUPREQ);
1841+ min = packet_get_int();
1842+ nbits = packet_get_int();
1843+ max = packet_get_int();
1844+ min = MAX(DH_GRP_MIN, min);
1845+ max = MIN(DH_GRP_MAX, max);
1846+ packet_check_eom();
1847+ if (max < min || nbits < min || max < nbits)
1848+ fatal("GSS_GEX, bad parameters: %d !< %d !< %d",
1849+ min, nbits, max);
1850+ dh = PRIVSEP(choose_dh(min, nbits, max));
1851+ if (dh == NULL)
1852+ packet_disconnect("Protocol error: no matching group found");
1853+
1854+ packet_start(SSH2_MSG_KEXGSS_GROUP);
1855+ packet_put_bignum2(dh->p);
1856+ packet_put_bignum2(dh->g);
1857+ packet_send();
1858+
1859+ packet_write_wait();
1860+ break;
1861+ default:
1862+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
1863+ }
1864+
1865+ dh_gen_key(dh, kex->we_need * 8);
1866+
1867+ do {
1868+ debug("Wait SSH2_MSG_GSSAPI_INIT");
1869+ type = packet_read();
1870+ switch(type) {
1871+ case SSH2_MSG_KEXGSS_INIT:
1872+ if (dh_client_pub != NULL)
1873+ fatal("Received KEXGSS_INIT after initialising");
1874+ recv_tok.value = packet_get_string(&slen);
1875+ recv_tok.length = slen;
1876+
1877+ if ((dh_client_pub = BN_new()) == NULL)
1878+ fatal("dh_client_pub == NULL");
1879+
1880+ packet_get_bignum2(dh_client_pub);
1881+
1882+ /* Send SSH_MSG_KEXGSS_HOSTKEY here, if we want */
1883+ break;
1884+ case SSH2_MSG_KEXGSS_CONTINUE:
1885+ recv_tok.value = packet_get_string(&slen);
1886+ recv_tok.length = slen;
1887+ break;
1888+ default:
1889+ packet_disconnect(
1890+ "Protocol error: didn't expect packet type %d",
1891+ type);
1892+ }
1893+
1894+ maj_status = PRIVSEP(ssh_gssapi_accept_ctx(ctxt, &recv_tok,
1895+ &send_tok, &ret_flags));
1896+
1897+ free(recv_tok.value);
1898+
1899+ if (maj_status != GSS_S_COMPLETE && send_tok.length == 0)
1900+ fatal("Zero length token output when incomplete");
1901+
1902+ if (dh_client_pub == NULL)
1903+ fatal("No client public key");
1904+
1905+ if (maj_status & GSS_S_CONTINUE_NEEDED) {
1906+ debug("Sending GSSAPI_CONTINUE");
1907+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1908+ packet_put_string(send_tok.value, send_tok.length);
1909+ packet_send();
1910+ gss_release_buffer(&min_status, &send_tok);
1911+ }
1912+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
1913+
1914+ if (GSS_ERROR(maj_status)) {
1915+ if (send_tok.length > 0) {
1916+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1917+ packet_put_string(send_tok.value, send_tok.length);
1918+ packet_send();
1919+ }
1920+ fatal("accept_ctx died");
1921+ }
1922+
1923+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
1924+ fatal("Mutual Authentication flag wasn't set");
1925+
1926+ if (!(ret_flags & GSS_C_INTEG_FLAG))
1927+ fatal("Integrity flag wasn't set");
1928+
1929+ if (!dh_pub_is_valid(dh, dh_client_pub))
1930+ packet_disconnect("bad client public DH value");
1931+
1932+ klen = DH_size(dh);
1933+ kbuf = xmalloc(klen);
1934+ kout = DH_compute_key(kbuf, dh_client_pub, dh);
1935+ if (kout < 0)
1936+ fatal("DH_compute_key: failed");
1937+
1938+ shared_secret = BN_new();
1939+ if (shared_secret == NULL)
1940+ fatal("kexgss_server: BN_new failed");
1941+
1942+ if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
1943+ fatal("kexgss_server: BN_bin2bn failed");
1944+
1945+ memset(kbuf, 0, klen);
1946+ free(kbuf);
1947+
1948+ switch (kex->kex_type) {
1949+ case KEX_GSS_GRP1_SHA1:
1950+ case KEX_GSS_GRP14_SHA1:
1951+ kex_dh_hash(
1952+ kex->client_version_string, kex->server_version_string,
1953+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
1954+ buffer_ptr(&kex->my), buffer_len(&kex->my),
1955+ NULL, 0, /* Change this if we start sending host keys */
1956+ dh_client_pub, dh->pub_key, shared_secret,
1957+ &hash, &hashlen
1958+ );
1959+ break;
1960+ case KEX_GSS_GEX_SHA1:
1961+ kexgex_hash(
1962+ kex->hash_alg,
1963+ kex->client_version_string, kex->server_version_string,
1964+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
1965+ buffer_ptr(&kex->my), buffer_len(&kex->my),
1966+ NULL, 0,
1967+ min, nbits, max,
1968+ dh->p, dh->g,
1969+ dh_client_pub,
1970+ dh->pub_key,
1971+ shared_secret,
1972+ &hash, &hashlen
1973+ );
1974+ break;
1975+ default:
1976+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
1977+ }
1978+
1979+ BN_clear_free(dh_client_pub);
1980+
1981+ if (kex->session_id == NULL) {
1982+ kex->session_id_len = hashlen;
1983+ kex->session_id = xmalloc(kex->session_id_len);
1984+ memcpy(kex->session_id, hash, kex->session_id_len);
1985+ }
1986+
1987+ gssbuf.value = hash;
1988+ gssbuf.length = hashlen;
1989+
1990+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_sign(ctxt,&gssbuf,&msg_tok))))
1991+ fatal("Couldn't get MIC");
1992+
1993+ packet_start(SSH2_MSG_KEXGSS_COMPLETE);
1994+ packet_put_bignum2(dh->pub_key);
1995+ packet_put_string(msg_tok.value,msg_tok.length);
1996+
1997+ if (send_tok.length != 0) {
1998+ packet_put_char(1); /* true */
1999+ packet_put_string(send_tok.value, send_tok.length);
2000+ } else {
2001+ packet_put_char(0); /* false */
2002+ }
2003+ packet_send();
2004+
2005+ gss_release_buffer(&min_status, &send_tok);
2006+ gss_release_buffer(&min_status, &msg_tok);
2007+
2008+ if (gss_kex_context == NULL)
2009+ gss_kex_context = ctxt;
2010+ else
2011+ ssh_gssapi_delete_ctx(&ctxt);
2012+
2013+ DH_free(dh);
2014+
2015+ kex_derive_keys_bn(kex, hash, hashlen, shared_secret);
2016+ BN_clear_free(shared_secret);
2017+ kex_finish(kex);
2018+
2019+ /* If this was a rekey, then save out any delegated credentials we
2020+ * just exchanged. */
2021+ if (options.gss_store_rekey)
2022+ ssh_gssapi_rekey_creds();
2023+}
2024+#endif /* GSSAPI */
2025diff --git a/key.c b/key.c
2026index 9142338..7ac844c 100644
2027--- a/key.c
2028+++ b/key.c
2029@@ -985,6 +985,7 @@ static const struct keytype keytypes[] = {
2030 KEY_DSA_CERT_V00, 0, 1 },
2031 { "ssh-ed25519-cert-v01@openssh.com", "ED25519-CERT",
2032 KEY_ED25519_CERT, 0, 1 },
2033+ { "null", "null", KEY_NULL, 0, 0 },
2034 { NULL, NULL, -1, -1, 0 }
2035 };
2036
2037@@ -1063,7 +1064,7 @@ key_alg_list(int certs_only, int plain_only)
2038 const struct keytype *kt;
2039
2040 for (kt = keytypes; kt->type != -1; kt++) {
2041- if (kt->name == NULL)
2042+ if (kt->name == NULL || kt->type == KEY_NULL)
2043 continue;
2044 if ((certs_only && !kt->cert) || (plain_only && kt->cert))
2045 continue;
2046diff --git a/key.h b/key.h
2047index d8ad13d..c8aeba2 100644
2048--- a/key.h
2049+++ b/key.h
2050@@ -46,6 +46,7 @@ enum types {
2051 KEY_ED25519_CERT,
2052 KEY_RSA_CERT_V00,
2053 KEY_DSA_CERT_V00,
2054+ KEY_NULL,
2055 KEY_UNSPEC
2056 };
2057 enum fp_type {
2058diff --git a/monitor.c b/monitor.c
2059index 03baf1e..a777c4c 100644
2060--- a/monitor.c
2061+++ b/monitor.c
2062@@ -181,6 +181,8 @@ int mm_answer_gss_setup_ctx(int, Buffer *);
2063 int mm_answer_gss_accept_ctx(int, Buffer *);
2064 int mm_answer_gss_userok(int, Buffer *);
2065 int mm_answer_gss_checkmic(int, Buffer *);
2066+int mm_answer_gss_sign(int, Buffer *);
2067+int mm_answer_gss_updatecreds(int, Buffer *);
2068 #endif
2069
2070 #ifdef SSH_AUDIT_EVENTS
2071@@ -253,6 +255,7 @@ struct mon_table mon_dispatch_proto20[] = {
2072 {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
2073 {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
2074 {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
2075+ {MONITOR_REQ_GSSSIGN, MON_ONCE, mm_answer_gss_sign},
2076 #endif
2077 #ifdef JPAKE
2078 {MONITOR_REQ_JPAKE_GET_PWDATA, MON_ONCE, mm_answer_jpake_get_pwdata},
2079@@ -265,6 +268,12 @@ struct mon_table mon_dispatch_proto20[] = {
2080 };
2081
2082 struct mon_table mon_dispatch_postauth20[] = {
2083+#ifdef GSSAPI
2084+ {MONITOR_REQ_GSSSETUP, 0, mm_answer_gss_setup_ctx},
2085+ {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
2086+ {MONITOR_REQ_GSSSIGN, 0, mm_answer_gss_sign},
2087+ {MONITOR_REQ_GSSUPCREDS, 0, mm_answer_gss_updatecreds},
2088+#endif
2089 {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
2090 {MONITOR_REQ_SIGN, 0, mm_answer_sign},
2091 {MONITOR_REQ_PTY, 0, mm_answer_pty},
2092@@ -373,6 +382,10 @@ monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
2093 /* Permit requests for moduli and signatures */
2094 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
2095 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
2096+#ifdef GSSAPI
2097+ /* and for the GSSAPI key exchange */
2098+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
2099+#endif
2100 } else {
2101 mon_dispatch = mon_dispatch_proto15;
2102
2103@@ -487,6 +500,10 @@ monitor_child_postauth(struct monitor *pmonitor)
2104 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
2105 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
2106 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
2107+#ifdef GSSAPI
2108+ /* and for the GSSAPI key exchange */
2109+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
2110+#endif
2111 } else {
2112 mon_dispatch = mon_dispatch_postauth15;
2113 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
2114@@ -1856,6 +1873,13 @@ mm_get_kex(Buffer *m)
2115 kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
2116 kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
2117 kex->kex[KEX_C25519_SHA256] = kexc25519_server;
2118+#ifdef GSSAPI
2119+ if (options.gss_keyex) {
2120+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
2121+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
2122+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_server;
2123+ }
2124+#endif
2125 kex->server = 1;
2126 kex->hostkey_type = buffer_get_int(m);
2127 kex->kex_type = buffer_get_int(m);
2128@@ -2063,6 +2087,9 @@ mm_answer_gss_setup_ctx(int sock, Buffer *m)
2129 OM_uint32 major;
2130 u_int len;
2131
2132+ if (!options.gss_authentication && !options.gss_keyex)
2133+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2134+
2135 goid.elements = buffer_get_string(m, &len);
2136 goid.length = len;
2137
2138@@ -2090,6 +2117,9 @@ mm_answer_gss_accept_ctx(int sock, Buffer *m)
2139 OM_uint32 flags = 0; /* GSI needs this */
2140 u_int len;
2141
2142+ if (!options.gss_authentication && !options.gss_keyex)
2143+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2144+
2145 in.value = buffer_get_string(m, &len);
2146 in.length = len;
2147 major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
2148@@ -2107,6 +2137,7 @@ mm_answer_gss_accept_ctx(int sock, Buffer *m)
2149 monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
2150 monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
2151 monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
2152+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSIGN, 1);
2153 }
2154 return (0);
2155 }
2156@@ -2118,6 +2149,9 @@ mm_answer_gss_checkmic(int sock, Buffer *m)
2157 OM_uint32 ret;
2158 u_int len;
2159
2160+ if (!options.gss_authentication && !options.gss_keyex)
2161+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2162+
2163 gssbuf.value = buffer_get_string(m, &len);
2164 gssbuf.length = len;
2165 mic.value = buffer_get_string(m, &len);
2166@@ -2144,7 +2178,11 @@ mm_answer_gss_userok(int sock, Buffer *m)
2167 {
2168 int authenticated;
2169
2170- authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
2171+ if (!options.gss_authentication && !options.gss_keyex)
2172+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2173+
2174+ authenticated = authctxt->valid &&
2175+ ssh_gssapi_userok(authctxt->user, authctxt->pw);
2176
2177 buffer_clear(m);
2178 buffer_put_int(m, authenticated);
2179@@ -2157,6 +2195,74 @@ mm_answer_gss_userok(int sock, Buffer *m)
2180 /* Monitor loop will terminate if authenticated */
2181 return (authenticated);
2182 }
2183+
2184+int
2185+mm_answer_gss_sign(int socket, Buffer *m)
2186+{
2187+ gss_buffer_desc data;
2188+ gss_buffer_desc hash = GSS_C_EMPTY_BUFFER;
2189+ OM_uint32 major, minor;
2190+ u_int len;
2191+
2192+ if (!options.gss_authentication && !options.gss_keyex)
2193+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2194+
2195+ data.value = buffer_get_string(m, &len);
2196+ data.length = len;
2197+ if (data.length != 20)
2198+ fatal("%s: data length incorrect: %d", __func__,
2199+ (int) data.length);
2200+
2201+ /* Save the session ID on the first time around */
2202+ if (session_id2_len == 0) {
2203+ session_id2_len = data.length;
2204+ session_id2 = xmalloc(session_id2_len);
2205+ memcpy(session_id2, data.value, session_id2_len);
2206+ }
2207+ major = ssh_gssapi_sign(gsscontext, &data, &hash);
2208+
2209+ free(data.value);
2210+
2211+ buffer_clear(m);
2212+ buffer_put_int(m, major);
2213+ buffer_put_string(m, hash.value, hash.length);
2214+
2215+ mm_request_send(socket, MONITOR_ANS_GSSSIGN, m);
2216+
2217+ gss_release_buffer(&minor, &hash);
2218+
2219+ /* Turn on getpwnam permissions */
2220+ monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
2221+
2222+ /* And credential updating, for when rekeying */
2223+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSUPCREDS, 1);
2224+
2225+ return (0);
2226+}
2227+
2228+int
2229+mm_answer_gss_updatecreds(int socket, Buffer *m) {
2230+ ssh_gssapi_ccache store;
2231+ int ok;
2232+
2233+ store.filename = buffer_get_string(m, NULL);
2234+ store.envvar = buffer_get_string(m, NULL);
2235+ store.envval = buffer_get_string(m, NULL);
2236+
2237+ ok = ssh_gssapi_update_creds(&store);
2238+
2239+ free(store.filename);
2240+ free(store.envvar);
2241+ free(store.envval);
2242+
2243+ buffer_clear(m);
2244+ buffer_put_int(m, ok);
2245+
2246+ mm_request_send(socket, MONITOR_ANS_GSSUPCREDS, m);
2247+
2248+ return(0);
2249+}
2250+
2251 #endif /* GSSAPI */
2252
2253 #ifdef JPAKE
2254diff --git a/monitor.h b/monitor.h
2255index 2caa469..315ef99 100644
2256--- a/monitor.h
2257+++ b/monitor.h
2258@@ -70,6 +70,9 @@ enum monitor_reqtype {
2259 MONITOR_REQ_PAM_FREE_CTX = 110, MONITOR_ANS_PAM_FREE_CTX = 111,
2260 MONITOR_REQ_AUDIT_EVENT = 112, MONITOR_REQ_AUDIT_COMMAND = 113,
2261
2262+ MONITOR_REQ_GSSSIGN = 150, MONITOR_ANS_GSSSIGN = 151,
2263+ MONITOR_REQ_GSSUPCREDS = 152, MONITOR_ANS_GSSUPCREDS = 153,
2264+
2265 };
2266
2267 struct mm_master;
2268diff --git a/monitor_wrap.c b/monitor_wrap.c
2269index 4ce4696..44019f3 100644
2270--- a/monitor_wrap.c
2271+++ b/monitor_wrap.c
2272@@ -1273,7 +1273,7 @@ mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
2273 }
2274
2275 int
2276-mm_ssh_gssapi_userok(char *user)
2277+mm_ssh_gssapi_userok(char *user, struct passwd *pw)
2278 {
2279 Buffer m;
2280 int authenticated = 0;
2281@@ -1290,6 +1290,51 @@ mm_ssh_gssapi_userok(char *user)
2282 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
2283 return (authenticated);
2284 }
2285+
2286+OM_uint32
2287+mm_ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_desc *data, gss_buffer_desc *hash)
2288+{
2289+ Buffer m;
2290+ OM_uint32 major;
2291+ u_int len;
2292+
2293+ buffer_init(&m);
2294+ buffer_put_string(&m, data->value, data->length);
2295+
2296+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSIGN, &m);
2297+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSIGN, &m);
2298+
2299+ major = buffer_get_int(&m);
2300+ hash->value = buffer_get_string(&m, &len);
2301+ hash->length = len;
2302+
2303+ buffer_free(&m);
2304+
2305+ return(major);
2306+}
2307+
2308+int
2309+mm_ssh_gssapi_update_creds(ssh_gssapi_ccache *store)
2310+{
2311+ Buffer m;
2312+ int ok;
2313+
2314+ buffer_init(&m);
2315+
2316+ buffer_put_cstring(&m, store->filename ? store->filename : "");
2317+ buffer_put_cstring(&m, store->envvar ? store->envvar : "");
2318+ buffer_put_cstring(&m, store->envval ? store->envval : "");
2319+
2320+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUPCREDS, &m);
2321+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUPCREDS, &m);
2322+
2323+ ok = buffer_get_int(&m);
2324+
2325+ buffer_free(&m);
2326+
2327+ return (ok);
2328+}
2329+
2330 #endif /* GSSAPI */
2331
2332 #ifdef JPAKE
2333diff --git a/monitor_wrap.h b/monitor_wrap.h
2334index 0c7f2e3..ec9b9b1 100644
2335--- a/monitor_wrap.h
2336+++ b/monitor_wrap.h
2337@@ -58,8 +58,10 @@ BIGNUM *mm_auth_rsa_generate_challenge(Key *);
2338 OM_uint32 mm_ssh_gssapi_server_ctx(Gssctxt **, gss_OID);
2339 OM_uint32 mm_ssh_gssapi_accept_ctx(Gssctxt *,
2340 gss_buffer_desc *, gss_buffer_desc *, OM_uint32 *);
2341-int mm_ssh_gssapi_userok(char *user);
2342+int mm_ssh_gssapi_userok(char *user, struct passwd *);
2343 OM_uint32 mm_ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
2344+OM_uint32 mm_ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
2345+int mm_ssh_gssapi_update_creds(ssh_gssapi_ccache *);
2346 #endif
2347
2348 #ifdef USE_PAM
2349diff --git a/readconf.c b/readconf.c
2350index 9c7e73d..cb8bcb2 100644
2351--- a/readconf.c
2352+++ b/readconf.c
2353@@ -140,6 +140,8 @@ typedef enum {
2354 oClearAllForwardings, oNoHostAuthenticationForLocalhost,
2355 oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout,
2356 oAddressFamily, oGssAuthentication, oGssDelegateCreds,
2357+ oGssTrustDns, oGssKeyEx, oGssClientIdentity, oGssRenewalRekey,
2358+ oGssServerIdentity,
2359 oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly,
2360 oSendEnv, oControlPath, oControlMaster, oControlPersist,
2361 oHashKnownHosts,
2362@@ -182,10 +184,19 @@ static struct {
2363 { "afstokenpassing", oUnsupported },
2364 #if defined(GSSAPI)
2365 { "gssapiauthentication", oGssAuthentication },
2366+ { "gssapikeyexchange", oGssKeyEx },
2367 { "gssapidelegatecredentials", oGssDelegateCreds },
2368+ { "gssapitrustdns", oGssTrustDns },
2369+ { "gssapiclientidentity", oGssClientIdentity },
2370+ { "gssapiserveridentity", oGssServerIdentity },
2371+ { "gssapirenewalforcesrekey", oGssRenewalRekey },
2372 #else
2373 { "gssapiauthentication", oUnsupported },
2374+ { "gssapikeyexchange", oUnsupported },
2375 { "gssapidelegatecredentials", oUnsupported },
2376+ { "gssapitrustdns", oUnsupported },
2377+ { "gssapiclientidentity", oUnsupported },
2378+ { "gssapirenewalforcesrekey", oUnsupported },
2379 #endif
2380 { "fallbacktorsh", oDeprecated },
2381 { "usersh", oDeprecated },
2382@@ -839,10 +850,30 @@ parse_time:
2383 intptr = &options->gss_authentication;
2384 goto parse_flag;
2385
2386+ case oGssKeyEx:
2387+ intptr = &options->gss_keyex;
2388+ goto parse_flag;
2389+
2390 case oGssDelegateCreds:
2391 intptr = &options->gss_deleg_creds;
2392 goto parse_flag;
2393
2394+ case oGssTrustDns:
2395+ intptr = &options->gss_trust_dns;
2396+ goto parse_flag;
2397+
2398+ case oGssClientIdentity:
2399+ charptr = &options->gss_client_identity;
2400+ goto parse_string;
2401+
2402+ case oGssServerIdentity:
2403+ charptr = &options->gss_server_identity;
2404+ goto parse_string;
2405+
2406+ case oGssRenewalRekey:
2407+ intptr = &options->gss_renewal_rekey;
2408+ goto parse_flag;
2409+
2410 case oBatchMode:
2411 intptr = &options->batch_mode;
2412 goto parse_flag;
2413@@ -1488,7 +1519,12 @@ initialize_options(Options * options)
2414 options->pubkey_authentication = -1;
2415 options->challenge_response_authentication = -1;
2416 options->gss_authentication = -1;
2417+ options->gss_keyex = -1;
2418 options->gss_deleg_creds = -1;
2419+ options->gss_trust_dns = -1;
2420+ options->gss_renewal_rekey = -1;
2421+ options->gss_client_identity = NULL;
2422+ options->gss_server_identity = NULL;
2423 options->password_authentication = -1;
2424 options->kbd_interactive_authentication = -1;
2425 options->kbd_interactive_devices = NULL;
2426@@ -1594,8 +1630,14 @@ fill_default_options(Options * options)
2427 options->challenge_response_authentication = 1;
2428 if (options->gss_authentication == -1)
2429 options->gss_authentication = 0;
2430+ if (options->gss_keyex == -1)
2431+ options->gss_keyex = 0;
2432 if (options->gss_deleg_creds == -1)
2433 options->gss_deleg_creds = 0;
2434+ if (options->gss_trust_dns == -1)
2435+ options->gss_trust_dns = 0;
2436+ if (options->gss_renewal_rekey == -1)
2437+ options->gss_renewal_rekey = 0;
2438 if (options->password_authentication == -1)
2439 options->password_authentication = 1;
2440 if (options->kbd_interactive_authentication == -1)
2441diff --git a/readconf.h b/readconf.h
2442index 2d7ea9f..826c676 100644
2443--- a/readconf.h
2444+++ b/readconf.h
2445@@ -54,7 +54,12 @@ typedef struct {
2446 int challenge_response_authentication;
2447 /* Try S/Key or TIS, authentication. */
2448 int gss_authentication; /* Try GSS authentication */
2449+ int gss_keyex; /* Try GSS key exchange */
2450 int gss_deleg_creds; /* Delegate GSS credentials */
2451+ int gss_trust_dns; /* Trust DNS for GSS canonicalization */
2452+ int gss_renewal_rekey; /* Credential renewal forces rekey */
2453+ char *gss_client_identity; /* Principal to initiate GSSAPI with */
2454+ char *gss_server_identity; /* GSSAPI target principal */
2455 int password_authentication; /* Try password
2456 * authentication. */
2457 int kbd_interactive_authentication; /* Try keyboard-interactive auth. */
2458diff --git a/servconf.c b/servconf.c
2459index 9bcd05b..29209e4 100644
2460--- a/servconf.c
2461+++ b/servconf.c
2462@@ -108,7 +108,10 @@ initialize_server_options(ServerOptions *options)
2463 options->kerberos_ticket_cleanup = -1;
2464 options->kerberos_get_afs_token = -1;
2465 options->gss_authentication=-1;
2466+ options->gss_keyex = -1;
2467 options->gss_cleanup_creds = -1;
2468+ options->gss_strict_acceptor = -1;
2469+ options->gss_store_rekey = -1;
2470 options->password_authentication = -1;
2471 options->kbd_interactive_authentication = -1;
2472 options->challenge_response_authentication = -1;
2473@@ -245,8 +248,14 @@ fill_default_server_options(ServerOptions *options)
2474 options->kerberos_get_afs_token = 0;
2475 if (options->gss_authentication == -1)
2476 options->gss_authentication = 0;
2477+ if (options->gss_keyex == -1)
2478+ options->gss_keyex = 0;
2479 if (options->gss_cleanup_creds == -1)
2480 options->gss_cleanup_creds = 1;
2481+ if (options->gss_strict_acceptor == -1)
2482+ options->gss_strict_acceptor = 1;
2483+ if (options->gss_store_rekey == -1)
2484+ options->gss_store_rekey = 0;
2485 if (options->password_authentication == -1)
2486 options->password_authentication = 1;
2487 if (options->kbd_interactive_authentication == -1)
2488@@ -343,7 +352,9 @@ typedef enum {
2489 sBanner, sUseDNS, sHostbasedAuthentication,
2490 sHostbasedUsesNameFromPacketOnly, sClientAliveInterval,
2491 sClientAliveCountMax, sAuthorizedKeysFile,
2492- sGssAuthentication, sGssCleanupCreds, sAcceptEnv, sPermitTunnel,
2493+ sGssAuthentication, sGssCleanupCreds, sGssStrictAcceptor,
2494+ sGssKeyEx, sGssStoreRekey,
2495+ sAcceptEnv, sPermitTunnel,
2496 sMatch, sPermitOpen, sForceCommand, sChrootDirectory,
2497 sUsePrivilegeSeparation, sAllowAgentForwarding,
2498 sZeroKnowledgePasswordAuthentication, sHostCertificate,
2499@@ -410,10 +421,20 @@ static struct {
2500 #ifdef GSSAPI
2501 { "gssapiauthentication", sGssAuthentication, SSHCFG_ALL },
2502 { "gssapicleanupcredentials", sGssCleanupCreds, SSHCFG_GLOBAL },
2503+ { "gssapicleanupcreds", sGssCleanupCreds, SSHCFG_GLOBAL },
2504+ { "gssapistrictacceptorcheck", sGssStrictAcceptor, SSHCFG_GLOBAL },
2505+ { "gssapikeyexchange", sGssKeyEx, SSHCFG_GLOBAL },
2506+ { "gssapistorecredentialsonrekey", sGssStoreRekey, SSHCFG_GLOBAL },
2507 #else
2508 { "gssapiauthentication", sUnsupported, SSHCFG_ALL },
2509 { "gssapicleanupcredentials", sUnsupported, SSHCFG_GLOBAL },
2510+ { "gssapicleanupcreds", sUnsupported, SSHCFG_GLOBAL },
2511+ { "gssapistrictacceptorcheck", sUnsupported, SSHCFG_GLOBAL },
2512+ { "gssapikeyexchange", sUnsupported, SSHCFG_GLOBAL },
2513+ { "gssapistorecredentialsonrekey", sUnsupported, SSHCFG_GLOBAL },
2514 #endif
2515+ { "gssusesessionccache", sUnsupported, SSHCFG_GLOBAL },
2516+ { "gssapiusesessioncredcache", sUnsupported, SSHCFG_GLOBAL },
2517 { "passwordauthentication", sPasswordAuthentication, SSHCFG_ALL },
2518 { "kbdinteractiveauthentication", sKbdInteractiveAuthentication, SSHCFG_ALL },
2519 { "challengeresponseauthentication", sChallengeResponseAuthentication, SSHCFG_GLOBAL },
2520@@ -1094,10 +1115,22 @@ process_server_config_line(ServerOptions *options, char *line,
2521 intptr = &options->gss_authentication;
2522 goto parse_flag;
2523
2524+ case sGssKeyEx:
2525+ intptr = &options->gss_keyex;
2526+ goto parse_flag;
2527+
2528 case sGssCleanupCreds:
2529 intptr = &options->gss_cleanup_creds;
2530 goto parse_flag;
2531
2532+ case sGssStrictAcceptor:
2533+ intptr = &options->gss_strict_acceptor;
2534+ goto parse_flag;
2535+
2536+ case sGssStoreRekey:
2537+ intptr = &options->gss_store_rekey;
2538+ goto parse_flag;
2539+
2540 case sPasswordAuthentication:
2541 intptr = &options->password_authentication;
2542 goto parse_flag;
2543@@ -2008,7 +2041,10 @@ dump_config(ServerOptions *o)
2544 #endif
2545 #ifdef GSSAPI
2546 dump_cfg_fmtint(sGssAuthentication, o->gss_authentication);
2547+ dump_cfg_fmtint(sGssKeyEx, o->gss_keyex);
2548 dump_cfg_fmtint(sGssCleanupCreds, o->gss_cleanup_creds);
2549+ dump_cfg_fmtint(sGssStrictAcceptor, o->gss_strict_acceptor);
2550+ dump_cfg_fmtint(sGssStoreRekey, o->gss_store_rekey);
2551 #endif
2552 #ifdef JPAKE
2553 dump_cfg_fmtint(sZeroKnowledgePasswordAuthentication,
2554diff --git a/servconf.h b/servconf.h
2555index 8812c5a..eba76ee 100644
2556--- a/servconf.h
2557+++ b/servconf.h
2558@@ -112,7 +112,10 @@ typedef struct {
2559 int kerberos_get_afs_token; /* If true, try to get AFS token if
2560 * authenticated with Kerberos. */
2561 int gss_authentication; /* If true, permit GSSAPI authentication */
2562+ int gss_keyex; /* If true, permit GSSAPI key exchange */
2563 int gss_cleanup_creds; /* If true, destroy cred cache on logout */
2564+ int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */
2565+ int gss_store_rekey;
2566 int password_authentication; /* If true, permit password
2567 * authentication. */
2568 int kbd_interactive_authentication; /* If true, permit */
2569diff --git a/ssh-gss.h b/ssh-gss.h
2570index 077e13c..885e481 100644
2571--- a/ssh-gss.h
2572+++ b/ssh-gss.h
2573@@ -1,6 +1,6 @@
2574 /* $OpenBSD: ssh-gss.h,v 1.10 2007/06/12 08:20:00 djm Exp $ */
2575 /*
2576- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
2577+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
2578 *
2579 * Redistribution and use in source and binary forms, with or without
2580 * modification, are permitted provided that the following conditions
2581@@ -61,10 +61,22 @@
2582
2583 #define SSH_GSS_OIDTYPE 0x06
2584
2585+#define SSH2_MSG_KEXGSS_INIT 30
2586+#define SSH2_MSG_KEXGSS_CONTINUE 31
2587+#define SSH2_MSG_KEXGSS_COMPLETE 32
2588+#define SSH2_MSG_KEXGSS_HOSTKEY 33
2589+#define SSH2_MSG_KEXGSS_ERROR 34
2590+#define SSH2_MSG_KEXGSS_GROUPREQ 40
2591+#define SSH2_MSG_KEXGSS_GROUP 41
2592+#define KEX_GSS_GRP1_SHA1_ID "gss-group1-sha1-"
2593+#define KEX_GSS_GRP14_SHA1_ID "gss-group14-sha1-"
2594+#define KEX_GSS_GEX_SHA1_ID "gss-gex-sha1-"
2595+
2596 typedef struct {
2597 char *filename;
2598 char *envvar;
2599 char *envval;
2600+ struct passwd *owner;
2601 void *data;
2602 } ssh_gssapi_ccache;
2603
2604@@ -72,8 +84,11 @@ typedef struct {
2605 gss_buffer_desc displayname;
2606 gss_buffer_desc exportedname;
2607 gss_cred_id_t creds;
2608+ gss_name_t name;
2609 struct ssh_gssapi_mech_struct *mech;
2610 ssh_gssapi_ccache store;
2611+ int used;
2612+ int updated;
2613 } ssh_gssapi_client;
2614
2615 typedef struct ssh_gssapi_mech_struct {
2616@@ -84,6 +99,7 @@ typedef struct ssh_gssapi_mech_struct {
2617 int (*userok) (ssh_gssapi_client *, char *);
2618 int (*localname) (ssh_gssapi_client *, char **);
2619 void (*storecreds) (ssh_gssapi_client *);
2620+ int (*updatecreds) (ssh_gssapi_ccache *, ssh_gssapi_client *);
2621 } ssh_gssapi_mech;
2622
2623 typedef struct {
2624@@ -94,10 +110,11 @@ typedef struct {
2625 gss_OID oid; /* client */
2626 gss_cred_id_t creds; /* server */
2627 gss_name_t client; /* server */
2628- gss_cred_id_t client_creds; /* server */
2629+ gss_cred_id_t client_creds; /* both */
2630 } Gssctxt;
2631
2632 extern ssh_gssapi_mech *supported_mechs[];
2633+extern Gssctxt *gss_kex_context;
2634
2635 int ssh_gssapi_check_oid(Gssctxt *, void *, size_t);
2636 void ssh_gssapi_set_oid_data(Gssctxt *, void *, size_t);
2637@@ -117,16 +134,32 @@ void ssh_gssapi_build_ctx(Gssctxt **);
2638 void ssh_gssapi_delete_ctx(Gssctxt **);
2639 OM_uint32 ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
2640 void ssh_gssapi_buildmic(Buffer *, const char *, const char *, const char *);
2641-int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *);
2642+int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *, const char *);
2643+OM_uint32 ssh_gssapi_client_identity(Gssctxt *, const char *);
2644+int ssh_gssapi_credentials_updated(Gssctxt *);
2645
2646 /* In the server */
2647+typedef int ssh_gssapi_check_fn(Gssctxt **, gss_OID, const char *,
2648+ const char *);
2649+char *ssh_gssapi_client_mechanisms(const char *, const char *);
2650+char *ssh_gssapi_kex_mechs(gss_OID_set, ssh_gssapi_check_fn *, const char *,
2651+ const char *);
2652+gss_OID ssh_gssapi_id_kex(Gssctxt *, char *, int);
2653+int ssh_gssapi_server_check_mech(Gssctxt **,gss_OID, const char *,
2654+ const char *);
2655 OM_uint32 ssh_gssapi_server_ctx(Gssctxt **, gss_OID);
2656-int ssh_gssapi_userok(char *name);
2657+int ssh_gssapi_userok(char *name, struct passwd *);
2658 OM_uint32 ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
2659 void ssh_gssapi_do_child(char ***, u_int *);
2660 void ssh_gssapi_cleanup_creds(void);
2661 void ssh_gssapi_storecreds(void);
2662
2663+char *ssh_gssapi_server_mechanisms(void);
2664+int ssh_gssapi_oid_table_ok(void);
2665+
2666+int ssh_gssapi_update_creds(ssh_gssapi_ccache *store);
2667+void ssh_gssapi_rekey_creds(void);
2668+
2669 #endif /* GSSAPI */
2670
2671 #endif /* _SSH_GSS_H */
2672diff --git a/ssh_config b/ssh_config
2673index 03a228f..228e5ab 100644
2674--- a/ssh_config
2675+++ b/ssh_config
2676@@ -26,6 +26,8 @@
2677 # HostbasedAuthentication no
2678 # GSSAPIAuthentication no
2679 # GSSAPIDelegateCredentials no
2680+# GSSAPIKeyExchange no
2681+# GSSAPITrustDNS no
2682 # BatchMode no
2683 # CheckHostIP yes
2684 # AddressFamily any
2685diff --git a/ssh_config.5 b/ssh_config.5
2686index 3cadcd7..49505ae 100644
2687--- a/ssh_config.5
2688+++ b/ssh_config.5
2689@@ -676,11 +676,43 @@ Specifies whether user authentication based on GSSAPI is allowed.
2690 The default is
2691 .Dq no .
2692 Note that this option applies to protocol version 2 only.
2693+.It Cm GSSAPIKeyExchange
2694+Specifies whether key exchange based on GSSAPI may be used. When using
2695+GSSAPI key exchange the server need not have a host key.
2696+The default is
2697+.Dq no .
2698+Note that this option applies to protocol version 2 only.
2699+.It Cm GSSAPIClientIdentity
2700+If set, specifies the GSSAPI client identity that ssh should use when
2701+connecting to the server. The default is unset, which means that the default
2702+identity will be used.
2703+.It Cm GSSAPIServerIdentity
2704+If set, specifies the GSSAPI server identity that ssh should expect when
2705+connecting to the server. The default is unset, which means that the
2706+expected GSSAPI server identity will be determined from the target
2707+hostname.
2708 .It Cm GSSAPIDelegateCredentials
2709 Forward (delegate) credentials to the server.
2710 The default is
2711 .Dq no .
2712-Note that this option applies to protocol version 2 only.
2713+Note that this option applies to protocol version 2 connections using GSSAPI.
2714+.It Cm GSSAPIRenewalForcesRekey
2715+If set to
2716+.Dq yes
2717+then renewal of the client's GSSAPI credentials will force the rekeying of the
2718+ssh connection. With a compatible server, this can delegate the renewed
2719+credentials to a session on the server.
2720+The default is
2721+.Dq no .
2722+.It Cm GSSAPITrustDns
2723+Set to
2724+.Dq yes to indicate that the DNS is trusted to securely canonicalize
2725+the name of the host being connected to. If
2726+.Dq no, the hostname entered on the
2727+command line will be passed untouched to the GSSAPI library.
2728+The default is
2729+.Dq no .
2730+This option only applies to protocol version 2 connections using GSSAPI.
2731 .It Cm HashKnownHosts
2732 Indicates that
2733 .Xr ssh 1
2734diff --git a/sshconnect2.c b/sshconnect2.c
2735index 8acffc5..21a269d 100644
2736--- a/sshconnect2.c
2737+++ b/sshconnect2.c
2738@@ -160,9 +160,34 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
2739 {
2740 Kex *kex;
2741
2742+#ifdef GSSAPI
2743+ char *orig = NULL, *gss = NULL;
2744+ char *gss_host = NULL;
2745+#endif
2746+
2747 xxx_host = host;
2748 xxx_hostaddr = hostaddr;
2749
2750+#ifdef GSSAPI
2751+ if (options.gss_keyex) {
2752+ /* Add the GSSAPI mechanisms currently supported on this
2753+ * client to the key exchange algorithm proposal */
2754+ orig = myproposal[PROPOSAL_KEX_ALGS];
2755+
2756+ if (options.gss_trust_dns)
2757+ gss_host = (char *)get_canonical_hostname(1);
2758+ else
2759+ gss_host = host;
2760+
2761+ gss = ssh_gssapi_client_mechanisms(gss_host, options.gss_client_identity);
2762+ if (gss) {
2763+ debug("Offering GSSAPI proposal: %s", gss);
2764+ xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
2765+ "%s,%s", gss, orig);
2766+ }
2767+ }
2768+#endif
2769+
2770 if (options.ciphers == (char *)-1) {
2771 logit("No valid ciphers for protocol version 2 given, using defaults.");
2772 options.ciphers = NULL;
2773@@ -198,6 +223,17 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
2774 if (options.kex_algorithms != NULL)
2775 myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
2776
2777+#ifdef GSSAPI
2778+ /* If we've got GSSAPI algorithms, then we also support the
2779+ * 'null' hostkey, as a last resort */
2780+ if (options.gss_keyex && gss) {
2781+ orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
2782+ xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],
2783+ "%s,null", orig);
2784+ free(gss);
2785+ }
2786+#endif
2787+
2788 if (options.rekey_limit || options.rekey_interval)
2789 packet_set_rekey_limits((u_int32_t)options.rekey_limit,
2790 (time_t)options.rekey_interval);
2791@@ -210,10 +246,30 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
2792 kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
2793 kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
2794 kex->kex[KEX_C25519_SHA256] = kexc25519_client;
2795+#ifdef GSSAPI
2796+ if (options.gss_keyex) {
2797+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_client;
2798+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_client;
2799+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_client;
2800+ }
2801+#endif
2802 kex->client_version_string=client_version_string;
2803 kex->server_version_string=server_version_string;
2804 kex->verify_host_key=&verify_host_key_callback;
2805
2806+#ifdef GSSAPI
2807+ if (options.gss_keyex) {
2808+ kex->gss_deleg_creds = options.gss_deleg_creds;
2809+ kex->gss_trust_dns = options.gss_trust_dns;
2810+ kex->gss_client = options.gss_client_identity;
2811+ if (options.gss_server_identity) {
2812+ kex->gss_host = options.gss_server_identity;
2813+ } else {
2814+ kex->gss_host = gss_host;
2815+ }
2816+ }
2817+#endif
2818+
2819 xxx_kex = kex;
2820
2821 dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
2822@@ -309,6 +365,7 @@ void input_gssapi_token(int type, u_int32_t, void *);
2823 void input_gssapi_hash(int type, u_int32_t, void *);
2824 void input_gssapi_error(int, u_int32_t, void *);
2825 void input_gssapi_errtok(int, u_int32_t, void *);
2826+int userauth_gsskeyex(Authctxt *authctxt);
2827 #endif
2828
2829 void userauth(Authctxt *, char *);
2830@@ -324,6 +381,11 @@ static char *authmethods_get(void);
2831
2832 Authmethod authmethods[] = {
2833 #ifdef GSSAPI
2834+ {"gssapi-keyex",
2835+ userauth_gsskeyex,
2836+ NULL,
2837+ &options.gss_authentication,
2838+ NULL},
2839 {"gssapi-with-mic",
2840 userauth_gssapi,
2841 NULL,
2842@@ -627,19 +689,31 @@ userauth_gssapi(Authctxt *authctxt)
2843 static u_int mech = 0;
2844 OM_uint32 min;
2845 int ok = 0;
2846+ const char *gss_host;
2847+
2848+ if (options.gss_server_identity)
2849+ gss_host = options.gss_server_identity;
2850+ else if (options.gss_trust_dns)
2851+ gss_host = get_canonical_hostname(1);
2852+ else
2853+ gss_host = authctxt->host;
2854
2855 /* Try one GSSAPI method at a time, rather than sending them all at
2856 * once. */
2857
2858 if (gss_supported == NULL)
2859- gss_indicate_mechs(&min, &gss_supported);
2860+ if (GSS_ERROR(gss_indicate_mechs(&min, &gss_supported))) {
2861+ gss_supported = NULL;
2862+ return 0;
2863+ }
2864
2865 /* Check to see if the mechanism is usable before we offer it */
2866 while (mech < gss_supported->count && !ok) {
2867 /* My DER encoding requires length<128 */
2868 if (gss_supported->elements[mech].length < 128 &&
2869 ssh_gssapi_check_mechanism(&gssctxt,
2870- &gss_supported->elements[mech], authctxt->host)) {
2871+ &gss_supported->elements[mech], gss_host,
2872+ options.gss_client_identity)) {
2873 ok = 1; /* Mechanism works */
2874 } else {
2875 mech++;
2876@@ -736,8 +810,8 @@ input_gssapi_response(int type, u_int32_t plen, void *ctxt)
2877 {
2878 Authctxt *authctxt = ctxt;
2879 Gssctxt *gssctxt;
2880- int oidlen;
2881- char *oidv;
2882+ u_int oidlen;
2883+ u_char *oidv;
2884
2885 if (authctxt == NULL)
2886 fatal("input_gssapi_response: no authentication context");
2887@@ -846,6 +920,48 @@ input_gssapi_error(int type, u_int32_t plen, void *ctxt)
2888 free(msg);
2889 free(lang);
2890 }
2891+
2892+int
2893+userauth_gsskeyex(Authctxt *authctxt)
2894+{
2895+ Buffer b;
2896+ gss_buffer_desc gssbuf;
2897+ gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
2898+ OM_uint32 ms;
2899+
2900+ static int attempt = 0;
2901+ if (attempt++ >= 1)
2902+ return (0);
2903+
2904+ if (gss_kex_context == NULL) {
2905+ debug("No valid Key exchange context");
2906+ return (0);
2907+ }
2908+
2909+ ssh_gssapi_buildmic(&b, authctxt->server_user, authctxt->service,
2910+ "gssapi-keyex");
2911+
2912+ gssbuf.value = buffer_ptr(&b);
2913+ gssbuf.length = buffer_len(&b);
2914+
2915+ if (GSS_ERROR(ssh_gssapi_sign(gss_kex_context, &gssbuf, &mic))) {
2916+ buffer_free(&b);
2917+ return (0);
2918+ }
2919+
2920+ packet_start(SSH2_MSG_USERAUTH_REQUEST);
2921+ packet_put_cstring(authctxt->server_user);
2922+ packet_put_cstring(authctxt->service);
2923+ packet_put_cstring(authctxt->method->name);
2924+ packet_put_string(mic.value, mic.length);
2925+ packet_send();
2926+
2927+ buffer_free(&b);
2928+ gss_release_buffer(&ms, &mic);
2929+
2930+ return (1);
2931+}
2932+
2933 #endif /* GSSAPI */
2934
2935 int
2936diff --git a/sshd.c b/sshd.c
2937index 25380c9..fe65132 100644
2938--- a/sshd.c
2939+++ b/sshd.c
2940@@ -122,6 +122,10 @@
2941 #include "ssh-sandbox.h"
2942 #include "version.h"
2943
2944+#ifdef USE_SECURITY_SESSION_API
2945+#include <Security/AuthSession.h>
2946+#endif
2947+
2948 #ifdef LIBWRAP
2949 #include <tcpd.h>
2950 #include <syslog.h>
2951@@ -1721,10 +1725,13 @@ main(int ac, char **av)
2952 logit("Disabling protocol version 1. Could not load host key");
2953 options.protocol &= ~SSH_PROTO_1;
2954 }
2955+#ifndef GSSAPI
2956+ /* The GSSAPI key exchange can run without a host key */
2957 if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) {
2958 logit("Disabling protocol version 2. Could not load host key");
2959 options.protocol &= ~SSH_PROTO_2;
2960 }
2961+#endif
2962 if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) {
2963 logit("sshd: no hostkeys available -- exiting.");
2964 exit(1);
2965@@ -2051,6 +2058,60 @@ main(int ac, char **av)
2966 remote_ip, remote_port,
2967 get_local_ipaddr(sock_in), get_local_port());
2968
2969+#ifdef USE_SECURITY_SESSION_API
2970+ /*
2971+ * Create a new security session for use by the new user login if
2972+ * the current session is the root session or we are not launched
2973+ * by inetd (eg: debugging mode or server mode). We do not
2974+ * necessarily need to create a session if we are launched from
2975+ * inetd because Panther xinetd will create a session for us.
2976+ *
2977+ * The only case where this logic will fail is if there is an
2978+ * inetd running in a non-root session which is not creating
2979+ * new sessions for us. Then all the users will end up in the
2980+ * same session (bad).
2981+ *
2982+ * When the client exits, the session will be destroyed for us
2983+ * automatically.
2984+ *
2985+ * We must create the session before any credentials are stored
2986+ * (including AFS pags, which happens a few lines below).
2987+ */
2988+ {
2989+ OSStatus err = 0;
2990+ SecuritySessionId sid = 0;
2991+ SessionAttributeBits sattrs = 0;
2992+
2993+ err = SessionGetInfo(callerSecuritySession, &sid, &sattrs);
2994+ if (err)
2995+ error("SessionGetInfo() failed with error %.8X",
2996+ (unsigned) err);
2997+ else
2998+ debug("Current Session ID is %.8X / Session Attributes are %.8X",
2999+ (unsigned) sid, (unsigned) sattrs);
3000+
3001+ if (inetd_flag && !(sattrs & sessionIsRoot))
3002+ debug("Running in inetd mode in a non-root session... "
3003+ "assuming inetd created the session for us.");
3004+ else {
3005+ debug("Creating new security session...");
3006+ err = SessionCreate(0, sessionHasTTY | sessionIsRemote);
3007+ if (err)
3008+ error("SessionCreate() failed with error %.8X",
3009+ (unsigned) err);
3010+
3011+ err = SessionGetInfo(callerSecuritySession, &sid,
3012+ &sattrs);
3013+ if (err)
3014+ error("SessionGetInfo() failed with error %.8X",
3015+ (unsigned) err);
3016+ else
3017+ debug("New Session ID is %.8X / Session Attributes are %.8X",
3018+ (unsigned) sid, (unsigned) sattrs);
3019+ }
3020+ }
3021+#endif
3022+
3023 /*
3024 * We don't want to listen forever unless the other side
3025 * successfully authenticates itself. So we set up an alarm which is
3026@@ -2456,6 +2517,48 @@ do_ssh2_kex(void)
3027 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = compat_pkalg_proposal(
3028 list_hostkey_types());
3029
3030+#ifdef GSSAPI
3031+ {
3032+ char *orig;
3033+ char *gss = NULL;
3034+ char *newstr = NULL;
3035+ orig = myproposal[PROPOSAL_KEX_ALGS];
3036+
3037+ /*
3038+ * If we don't have a host key, then there's no point advertising
3039+ * the other key exchange algorithms
3040+ */
3041+
3042+ if (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]) == 0)
3043+ orig = NULL;
3044+
3045+ if (options.gss_keyex)
3046+ gss = ssh_gssapi_server_mechanisms();
3047+ else
3048+ gss = NULL;
3049+
3050+ if (gss && orig)
3051+ xasprintf(&newstr, "%s,%s", gss, orig);
3052+ else if (gss)
3053+ newstr = gss;
3054+ else if (orig)
3055+ newstr = orig;
3056+
3057+ /*
3058+ * If we've got GSSAPI mechanisms, then we've got the 'null' host
3059+ * key alg, but we can't tell people about it unless its the only
3060+ * host key algorithm we support
3061+ */
3062+ if (gss && (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS])) == 0)
3063+ myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = "null";
3064+
3065+ if (newstr)
3066+ myproposal[PROPOSAL_KEX_ALGS] = newstr;
3067+ else
3068+ fatal("No supported key exchange algorithms");
3069+ }
3070+#endif
3071+
3072 /* start key exchange */
3073 kex = kex_setup(myproposal);
3074 kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
3075@@ -2464,6 +2567,13 @@ do_ssh2_kex(void)
3076 kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
3077 kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
3078 kex->kex[KEX_C25519_SHA256] = kexc25519_server;
3079+#ifdef GSSAPI
3080+ if (options.gss_keyex) {
3081+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
3082+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
3083+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_server;
3084+ }
3085+#endif
3086 kex->server = 1;
3087 kex->client_version_string=client_version_string;
3088 kex->server_version_string=server_version_string;
3089diff --git a/sshd_config b/sshd_config
3090index e9045bc..d9b8594 100644
3091--- a/sshd_config
3092+++ b/sshd_config
3093@@ -84,6 +84,8 @@ AuthorizedKeysFile .ssh/authorized_keys
3094 # GSSAPI options
3095 #GSSAPIAuthentication no
3096 #GSSAPICleanupCredentials yes
3097+#GSSAPIStrictAcceptorCheck yes
3098+#GSSAPIKeyExchange no
3099
3100 # Set this to 'yes' to enable PAM authentication, account processing,
3101 # and session processing. If this is enabled, PAM authentication will
3102diff --git a/sshd_config.5 b/sshd_config.5
3103index 3b21ea6..9aa9eba 100644
3104--- a/sshd_config.5
3105+++ b/sshd_config.5
3106@@ -493,12 +493,40 @@ Specifies whether user authentication based on GSSAPI is allowed.
3107 The default is
3108 .Dq no .
3109 Note that this option applies to protocol version 2 only.
3110+.It Cm GSSAPIKeyExchange
3111+Specifies whether key exchange based on GSSAPI is allowed. GSSAPI key exchange
3112+doesn't rely on ssh keys to verify host identity.
3113+The default is
3114+.Dq no .
3115+Note that this option applies to protocol version 2 only.
3116 .It Cm GSSAPICleanupCredentials
3117 Specifies whether to automatically destroy the user's credentials cache
3118 on logout.
3119 The default is
3120 .Dq yes .
3121 Note that this option applies to protocol version 2 only.
3122+.It Cm GSSAPIStrictAcceptorCheck
3123+Determines whether to be strict about the identity of the GSSAPI acceptor
3124+a client authenticates against. If
3125+.Dq yes
3126+then the client must authenticate against the
3127+.Pa host
3128+service on the current hostname. If
3129+.Dq no
3130+then the client may authenticate against any service key stored in the
3131+machine's default store. This facility is provided to assist with operation
3132+on multi homed machines.
3133+The default is
3134+.Dq yes .
3135+Note that this option applies only to protocol version 2 GSSAPI connections,
3136+and setting it to
3137+.Dq no
3138+may only work with recent Kerberos GSSAPI libraries.
3139+.It Cm GSSAPIStoreCredentialsOnRekey
3140+Controls whether the user's GSSAPI credentials should be updated following a
3141+successful connection rekeying. This option can be used to accepted renewed
3142+or updated credentials from a compatible client. The default is
3143+.Dq no .
3144 .It Cm HostbasedAuthentication
3145 Specifies whether rhosts or /etc/hosts.equiv authentication together
3146 with successful public key client host authentication is allowed
generated by cgit v1.2.3 (git 2.39.1) at 2024-09-05 23:24:16 +0000