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-rw-r--r--debian/patches/gssapi.patch3027
1 files changed, 3027 insertions, 0 deletions
diff --git a/debian/patches/gssapi.patch b/debian/patches/gssapi.patch
new file mode 100644
index 000000000..aa9f25848
--- /dev/null
+++ b/debian/patches/gssapi.patch
@@ -0,0 +1,3027 @@
1From 374db1757fc18bd6647539b80977e6907a2cecd4 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: 2016-01-04
21
22Patch-Name: gssapi.patch
23---
24 ChangeLog.gssapi | 113 +++++++++++++++++++
25 Makefile.in | 3 +-
26 auth-krb5.c | 17 ++-
27 auth.c | 3 +-
28 auth2-gss.c | 48 +++++++-
29 auth2.c | 2 +
30 clientloop.c | 15 ++-
31 config.h.in | 6 +
32 configure.ac | 24 ++++
33 gss-genr.c | 275 ++++++++++++++++++++++++++++++++++++++++++++-
34 gss-serv-krb5.c | 85 ++++++++++++--
35 gss-serv.c | 185 +++++++++++++++++++++++++++---
36 kex.c | 16 +++
37 kex.h | 14 +++
38 kexgssc.c | 336 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
39 kexgsss.c | 295 ++++++++++++++++++++++++++++++++++++++++++++++++
40 monitor.c | 108 +++++++++++++++++-
41 monitor.h | 3 +
42 monitor_wrap.c | 47 +++++++-
43 monitor_wrap.h | 4 +-
44 readconf.c | 42 +++++++
45 readconf.h | 5 +
46 servconf.c | 28 ++++-
47 servconf.h | 2 +
48 ssh-gss.h | 41 ++++++-
49 ssh_config | 2 +
50 ssh_config.5 | 32 ++++++
51 sshconnect2.c | 120 +++++++++++++++++++-
52 sshd.c | 110 ++++++++++++++++++
53 sshd_config | 2 +
54 sshd_config.5 | 10 ++
55 sshkey.c | 3 +-
56 sshkey.h | 1 +
57 33 files changed, 1951 insertions(+), 46 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 d401787..0954c63 100644
183--- a/Makefile.in
184+++ b/Makefile.in
185@@ -92,6 +92,7 @@ LIBSSH_OBJS=${LIBOPENSSH_OBJS} \
186 kex.o kexdh.o kexgex.o kexecdh.o kexc25519.o \
187 kexdhc.o kexgexc.o kexecdhc.o kexc25519c.o \
188 kexdhs.o kexgexs.o kexecdhs.o kexc25519s.o \
189+ kexgssc.o \
190 platform-pledge.o
191
192 SSHOBJS= ssh.o readconf.o clientloop.o sshtty.o \
193@@ -105,7 +106,7 @@ SSHDOBJS=sshd.o auth-rhosts.o auth-passwd.o auth-rsa.o auth-rh-rsa.o \
194 auth-skey.o auth-bsdauth.o auth2-hostbased.o auth2-kbdint.o \
195 auth2-none.o auth2-passwd.o auth2-pubkey.o \
196 monitor_mm.o monitor.o monitor_wrap.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 sandbox-null.o sandbox-rlimit.o sandbox-systrace.o sandbox-darwin.o \
202diff --git a/auth-krb5.c b/auth-krb5.c
203index d1c5a2f..f019fb1 100644
204--- a/auth-krb5.c
205+++ b/auth-krb5.c
206@@ -183,8 +183,13 @@ 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@@ -241,15 +246,22 @@ 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@@ -266,6 +278,7 @@ 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/auth.c b/auth.c
254index 214c2c7..bd6a026 100644
255--- a/auth.c
256+++ b/auth.c
257@@ -354,7 +354,8 @@ auth_root_allowed(const char *method)
258 case PERMIT_NO_PASSWD:
259 if (strcmp(method, "publickey") == 0 ||
260 strcmp(method, "hostbased") == 0 ||
261- strcmp(method, "gssapi-with-mic") == 0)
262+ strcmp(method, "gssapi-with-mic") == 0 ||
263+ strcmp(method, "gssapi-keyex") == 0)
264 return 1;
265 break;
266 case PERMIT_FORCED_ONLY:
267diff --git a/auth2-gss.c b/auth2-gss.c
268index 1ca8357..3b5036d 100644
269--- a/auth2-gss.c
270+++ b/auth2-gss.c
271@@ -1,7 +1,7 @@
272 /* $OpenBSD: auth2-gss.c,v 1.22 2015/01/19 20:07:45 markus Exp $ */
273
274 /*
275- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
276+ * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
277 *
278 * Redistribution and use in source and binary forms, with or without
279 * modification, are permitted provided that the following conditions
280@@ -53,6 +53,40 @@ static int input_gssapi_mic(int type, u_int32_t plen, void *ctxt);
281 static int input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt);
282 static int input_gssapi_errtok(int, u_int32_t, void *);
283
284+/*
285+ * The 'gssapi_keyex' userauth mechanism.
286+ */
287+static int
288+userauth_gsskeyex(Authctxt *authctxt)
289+{
290+ int authenticated = 0;
291+ Buffer b;
292+ gss_buffer_desc mic, gssbuf;
293+ u_int len;
294+
295+ mic.value = packet_get_string(&len);
296+ mic.length = len;
297+
298+ packet_check_eom();
299+
300+ ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
301+ "gssapi-keyex");
302+
303+ gssbuf.value = buffer_ptr(&b);
304+ gssbuf.length = buffer_len(&b);
305+
306+ /* gss_kex_context is NULL with privsep, so we can't check it here */
307+ if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gss_kex_context,
308+ &gssbuf, &mic))))
309+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
310+ authctxt->pw));
311+
312+ buffer_free(&b);
313+ free(mic.value);
314+
315+ return (authenticated);
316+}
317+
318 /*
319 * We only support those mechanisms that we know about (ie ones that we know
320 * how to check local user kuserok and the like)
321@@ -238,7 +272,8 @@ input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt)
322
323 packet_check_eom();
324
325- authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
326+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
327+ authctxt->pw));
328
329 authctxt->postponed = 0;
330 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
331@@ -274,7 +309,8 @@ input_gssapi_mic(int type, u_int32_t plen, void *ctxt)
332 gssbuf.length = buffer_len(&b);
333
334 if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gssctxt, &gssbuf, &mic))))
335- authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
336+ authenticated =
337+ PRIVSEP(ssh_gssapi_userok(authctxt->user, authctxt->pw));
338 else
339 logit("GSSAPI MIC check failed");
340
341@@ -290,6 +326,12 @@ input_gssapi_mic(int type, u_int32_t plen, void *ctxt)
342 return 0;
343 }
344
345+Authmethod method_gsskeyex = {
346+ "gssapi-keyex",
347+ userauth_gsskeyex,
348+ &options.gss_authentication
349+};
350+
351 Authmethod method_gssapi = {
352 "gssapi-with-mic",
353 userauth_gssapi,
354diff --git a/auth2.c b/auth2.c
355index 7177962..3f49bdc 100644
356--- a/auth2.c
357+++ b/auth2.c
358@@ -70,6 +70,7 @@ extern Authmethod method_passwd;
359 extern Authmethod method_kbdint;
360 extern Authmethod method_hostbased;
361 #ifdef GSSAPI
362+extern Authmethod method_gsskeyex;
363 extern Authmethod method_gssapi;
364 #endif
365
366@@ -77,6 +78,7 @@ Authmethod *authmethods[] = {
367 &method_none,
368 &method_pubkey,
369 #ifdef GSSAPI
370+ &method_gsskeyex,
371 &method_gssapi,
372 #endif
373 &method_passwd,
374diff --git a/clientloop.c b/clientloop.c
375index 9820455..1567e4a 100644
376--- a/clientloop.c
377+++ b/clientloop.c
378@@ -114,6 +114,10 @@
379 #include "ssherr.h"
380 #include "hostfile.h"
381
382+#ifdef GSSAPI
383+#include "ssh-gss.h"
384+#endif
385+
386 /* import options */
387 extern Options options;
388
389@@ -1662,9 +1666,18 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
390 break;
391
392 /* Do channel operations unless rekeying in progress. */
393- if (!ssh_packet_is_rekeying(active_state))
394+ if (!ssh_packet_is_rekeying(active_state)) {
395 channel_after_select(readset, writeset);
396
397+#ifdef GSSAPI
398+ if (options.gss_renewal_rekey &&
399+ ssh_gssapi_credentials_updated(NULL)) {
400+ debug("credentials updated - forcing rekey");
401+ need_rekeying = 1;
402+ }
403+#endif
404+ }
405+
406 /* Buffer input from the connection. */
407 client_process_net_input(readset);
408
409diff --git a/config.h.in b/config.h.in
410index 89bf1b0..621c139 100644
411--- a/config.h.in
412+++ b/config.h.in
413@@ -1641,6 +1641,9 @@
414 /* Use btmp to log bad logins */
415 #undef USE_BTMP
416
417+/* platform uses an in-memory credentials cache */
418+#undef USE_CCAPI
419+
420 /* Use libedit for sftp */
421 #undef USE_LIBEDIT
422
423@@ -1656,6 +1659,9 @@
424 /* Use PIPES instead of a socketpair() */
425 #undef USE_PIPES
426
427+/* platform has the Security Authorization Session API */
428+#undef USE_SECURITY_SESSION_API
429+
430 /* Define if you have Solaris privileges */
431 #undef USE_SOLARIS_PRIVS
432
433diff --git a/configure.ac b/configure.ac
434index 7258cc0..5f1ff74 100644
435--- a/configure.ac
436+++ b/configure.ac
437@@ -632,6 +632,30 @@ main() { if (NSVersionOfRunTimeLibrary("System") >= (60 << 16))
438 [Use tunnel device compatibility to OpenBSD])
439 AC_DEFINE([SSH_TUN_PREPEND_AF], [1],
440 [Prepend the address family to IP tunnel traffic])
441+ AC_MSG_CHECKING([if we have the Security Authorization Session API])
442+ AC_TRY_COMPILE([#include <Security/AuthSession.h>],
443+ [SessionCreate(0, 0);],
444+ [ac_cv_use_security_session_api="yes"
445+ AC_DEFINE([USE_SECURITY_SESSION_API], [1],
446+ [platform has the Security Authorization Session API])
447+ LIBS="$LIBS -framework Security"
448+ AC_MSG_RESULT([yes])],
449+ [ac_cv_use_security_session_api="no"
450+ AC_MSG_RESULT([no])])
451+ AC_MSG_CHECKING([if we have an in-memory credentials cache])
452+ AC_TRY_COMPILE(
453+ [#include <Kerberos/Kerberos.h>],
454+ [cc_context_t c;
455+ (void) cc_initialize (&c, 0, NULL, NULL);],
456+ [AC_DEFINE([USE_CCAPI], [1],
457+ [platform uses an in-memory credentials cache])
458+ LIBS="$LIBS -framework Security"
459+ AC_MSG_RESULT([yes])
460+ if test "x$ac_cv_use_security_session_api" = "xno"; then
461+ AC_MSG_ERROR([*** Need a security framework to use the credentials cache API ***])
462+ fi],
463+ [AC_MSG_RESULT([no])]
464+ )
465 m4_pattern_allow([AU_IPv])
466 AC_CHECK_DECL([AU_IPv4], [],
467 AC_DEFINE([AU_IPv4], [0], [System only supports IPv4 audit records])
468diff --git a/gss-genr.c b/gss-genr.c
469index d617d60..b4eca3f 100644
470--- a/gss-genr.c
471+++ b/gss-genr.c
472@@ -1,7 +1,7 @@
473 /* $OpenBSD: gss-genr.c,v 1.23 2015/01/20 23:14:00 deraadt Exp $ */
474
475 /*
476- * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
477+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
478 *
479 * Redistribution and use in source and binary forms, with or without
480 * modification, are permitted provided that the following conditions
481@@ -41,12 +41,167 @@
482 #include "buffer.h"
483 #include "log.h"
484 #include "ssh2.h"
485+#include "cipher.h"
486+#include "key.h"
487+#include "kex.h"
488+#include <openssl/evp.h>
489
490 #include "ssh-gss.h"
491
492 extern u_char *session_id2;
493 extern u_int session_id2_len;
494
495+typedef struct {
496+ char *encoded;
497+ gss_OID oid;
498+} ssh_gss_kex_mapping;
499+
500+/*
501+ * XXX - It would be nice to find a more elegant way of handling the
502+ * XXX passing of the key exchange context to the userauth routines
503+ */
504+
505+Gssctxt *gss_kex_context = NULL;
506+
507+static ssh_gss_kex_mapping *gss_enc2oid = NULL;
508+
509+int
510+ssh_gssapi_oid_table_ok(void) {
511+ return (gss_enc2oid != NULL);
512+}
513+
514+/*
515+ * Return a list of the gss-group1-sha1 mechanisms supported by this program
516+ *
517+ * We test mechanisms to ensure that we can use them, to avoid starting
518+ * a key exchange with a bad mechanism
519+ */
520+
521+char *
522+ssh_gssapi_client_mechanisms(const char *host, const char *client) {
523+ gss_OID_set gss_supported;
524+ OM_uint32 min_status;
525+
526+ if (GSS_ERROR(gss_indicate_mechs(&min_status, &gss_supported)))
527+ return NULL;
528+
529+ return(ssh_gssapi_kex_mechs(gss_supported, ssh_gssapi_check_mechanism,
530+ host, client));
531+}
532+
533+char *
534+ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
535+ const char *host, const char *client) {
536+ Buffer buf;
537+ size_t i;
538+ int oidpos, enclen;
539+ char *mechs, *encoded;
540+ u_char digest[EVP_MAX_MD_SIZE];
541+ char deroid[2];
542+ const EVP_MD *evp_md = EVP_md5();
543+ EVP_MD_CTX md;
544+
545+ if (gss_enc2oid != NULL) {
546+ for (i = 0; gss_enc2oid[i].encoded != NULL; i++)
547+ free(gss_enc2oid[i].encoded);
548+ free(gss_enc2oid);
549+ }
550+
551+ gss_enc2oid = xmalloc(sizeof(ssh_gss_kex_mapping) *
552+ (gss_supported->count + 1));
553+
554+ buffer_init(&buf);
555+
556+ oidpos = 0;
557+ for (i = 0; i < gss_supported->count; i++) {
558+ if (gss_supported->elements[i].length < 128 &&
559+ (*check)(NULL, &(gss_supported->elements[i]), host, client)) {
560+
561+ deroid[0] = SSH_GSS_OIDTYPE;
562+ deroid[1] = gss_supported->elements[i].length;
563+
564+ EVP_DigestInit(&md, evp_md);
565+ EVP_DigestUpdate(&md, deroid, 2);
566+ EVP_DigestUpdate(&md,
567+ gss_supported->elements[i].elements,
568+ gss_supported->elements[i].length);
569+ EVP_DigestFinal(&md, digest, NULL);
570+
571+ encoded = xmalloc(EVP_MD_size(evp_md) * 2);
572+ enclen = __b64_ntop(digest, EVP_MD_size(evp_md),
573+ encoded, EVP_MD_size(evp_md) * 2);
574+
575+ if (oidpos != 0)
576+ buffer_put_char(&buf, ',');
577+
578+ buffer_append(&buf, KEX_GSS_GEX_SHA1_ID,
579+ sizeof(KEX_GSS_GEX_SHA1_ID) - 1);
580+ buffer_append(&buf, encoded, enclen);
581+ buffer_put_char(&buf, ',');
582+ buffer_append(&buf, KEX_GSS_GRP1_SHA1_ID,
583+ sizeof(KEX_GSS_GRP1_SHA1_ID) - 1);
584+ buffer_append(&buf, encoded, enclen);
585+ buffer_put_char(&buf, ',');
586+ buffer_append(&buf, KEX_GSS_GRP14_SHA1_ID,
587+ sizeof(KEX_GSS_GRP14_SHA1_ID) - 1);
588+ buffer_append(&buf, encoded, enclen);
589+
590+ gss_enc2oid[oidpos].oid = &(gss_supported->elements[i]);
591+ gss_enc2oid[oidpos].encoded = encoded;
592+ oidpos++;
593+ }
594+ }
595+ gss_enc2oid[oidpos].oid = NULL;
596+ gss_enc2oid[oidpos].encoded = NULL;
597+
598+ buffer_put_char(&buf, '\0');
599+
600+ mechs = xmalloc(buffer_len(&buf));
601+ buffer_get(&buf, mechs, buffer_len(&buf));
602+ buffer_free(&buf);
603+
604+ if (strlen(mechs) == 0) {
605+ free(mechs);
606+ mechs = NULL;
607+ }
608+
609+ return (mechs);
610+}
611+
612+gss_OID
613+ssh_gssapi_id_kex(Gssctxt *ctx, char *name, int kex_type) {
614+ int i = 0;
615+
616+ switch (kex_type) {
617+ case KEX_GSS_GRP1_SHA1:
618+ if (strlen(name) < sizeof(KEX_GSS_GRP1_SHA1_ID))
619+ return GSS_C_NO_OID;
620+ name += sizeof(KEX_GSS_GRP1_SHA1_ID) - 1;
621+ break;
622+ case KEX_GSS_GRP14_SHA1:
623+ if (strlen(name) < sizeof(KEX_GSS_GRP14_SHA1_ID))
624+ return GSS_C_NO_OID;
625+ name += sizeof(KEX_GSS_GRP14_SHA1_ID) - 1;
626+ break;
627+ case KEX_GSS_GEX_SHA1:
628+ if (strlen(name) < sizeof(KEX_GSS_GEX_SHA1_ID))
629+ return GSS_C_NO_OID;
630+ name += sizeof(KEX_GSS_GEX_SHA1_ID) - 1;
631+ break;
632+ default:
633+ return GSS_C_NO_OID;
634+ }
635+
636+ while (gss_enc2oid[i].encoded != NULL &&
637+ strcmp(name, gss_enc2oid[i].encoded) != 0)
638+ i++;
639+
640+ if (gss_enc2oid[i].oid != NULL && ctx != NULL)
641+ ssh_gssapi_set_oid(ctx, gss_enc2oid[i].oid);
642+
643+ return gss_enc2oid[i].oid;
644+}
645+
646 /* Check that the OID in a data stream matches that in the context */
647 int
648 ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
649@@ -199,7 +354,7 @@ ssh_gssapi_init_ctx(Gssctxt *ctx, int deleg_creds, gss_buffer_desc *recv_tok,
650 }
651
652 ctx->major = gss_init_sec_context(&ctx->minor,
653- GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
654+ ctx->client_creds, &ctx->context, ctx->name, ctx->oid,
655 GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG | deleg_flag,
656 0, NULL, recv_tok, NULL, send_tok, flags, NULL);
657
658@@ -229,8 +384,42 @@ ssh_gssapi_import_name(Gssctxt *ctx, const char *host)
659 }
660
661 OM_uint32
662+ssh_gssapi_client_identity(Gssctxt *ctx, const char *name)
663+{
664+ gss_buffer_desc gssbuf;
665+ gss_name_t gssname;
666+ OM_uint32 status;
667+ gss_OID_set oidset;
668+
669+ gssbuf.value = (void *) name;
670+ gssbuf.length = strlen(gssbuf.value);
671+
672+ gss_create_empty_oid_set(&status, &oidset);
673+ gss_add_oid_set_member(&status, ctx->oid, &oidset);
674+
675+ ctx->major = gss_import_name(&ctx->minor, &gssbuf,
676+ GSS_C_NT_USER_NAME, &gssname);
677+
678+ if (!ctx->major)
679+ ctx->major = gss_acquire_cred(&ctx->minor,
680+ gssname, 0, oidset, GSS_C_INITIATE,
681+ &ctx->client_creds, NULL, NULL);
682+
683+ gss_release_name(&status, &gssname);
684+ gss_release_oid_set(&status, &oidset);
685+
686+ if (ctx->major)
687+ ssh_gssapi_error(ctx);
688+
689+ return(ctx->major);
690+}
691+
692+OM_uint32
693 ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
694 {
695+ if (ctx == NULL)
696+ return -1;
697+
698 if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
699 GSS_C_QOP_DEFAULT, buffer, hash)))
700 ssh_gssapi_error(ctx);
701@@ -238,6 +427,19 @@ ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
702 return (ctx->major);
703 }
704
705+/* Priviledged when used by server */
706+OM_uint32
707+ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
708+{
709+ if (ctx == NULL)
710+ return -1;
711+
712+ ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
713+ gssbuf, gssmic, NULL);
714+
715+ return (ctx->major);
716+}
717+
718 void
719 ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
720 const char *context)
721@@ -251,11 +453,16 @@ ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
722 }
723
724 int
725-ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
726+ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host,
727+ const char *client)
728 {
729 gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
730 OM_uint32 major, minor;
731 gss_OID_desc spnego_oid = {6, (void *)"\x2B\x06\x01\x05\x05\x02"};
732+ Gssctxt *intctx = NULL;
733+
734+ if (ctx == NULL)
735+ ctx = &intctx;
736
737 /* RFC 4462 says we MUST NOT do SPNEGO */
738 if (oid->length == spnego_oid.length &&
739@@ -265,6 +472,10 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
740 ssh_gssapi_build_ctx(ctx);
741 ssh_gssapi_set_oid(*ctx, oid);
742 major = ssh_gssapi_import_name(*ctx, host);
743+
744+ if (!GSS_ERROR(major) && client)
745+ major = ssh_gssapi_client_identity(*ctx, client);
746+
747 if (!GSS_ERROR(major)) {
748 major = ssh_gssapi_init_ctx(*ctx, 0, GSS_C_NO_BUFFER, &token,
749 NULL);
750@@ -274,10 +485,66 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
751 GSS_C_NO_BUFFER);
752 }
753
754- if (GSS_ERROR(major))
755+ if (GSS_ERROR(major) || intctx != NULL)
756 ssh_gssapi_delete_ctx(ctx);
757
758 return (!GSS_ERROR(major));
759 }
760
761+int
762+ssh_gssapi_credentials_updated(Gssctxt *ctxt) {
763+ static gss_name_t saved_name = GSS_C_NO_NAME;
764+ static OM_uint32 saved_lifetime = 0;
765+ static gss_OID saved_mech = GSS_C_NO_OID;
766+ static gss_name_t name;
767+ static OM_uint32 last_call = 0;
768+ OM_uint32 lifetime, now, major, minor;
769+ int equal;
770+
771+ now = time(NULL);
772+
773+ if (ctxt) {
774+ debug("Rekey has happened - updating saved versions");
775+
776+ if (saved_name != GSS_C_NO_NAME)
777+ gss_release_name(&minor, &saved_name);
778+
779+ major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
780+ &saved_name, &saved_lifetime, NULL, NULL);
781+
782+ if (!GSS_ERROR(major)) {
783+ saved_mech = ctxt->oid;
784+ saved_lifetime+= now;
785+ } else {
786+ /* Handle the error */
787+ }
788+ return 0;
789+ }
790+
791+ if (now - last_call < 10)
792+ return 0;
793+
794+ last_call = now;
795+
796+ if (saved_mech == GSS_C_NO_OID)
797+ return 0;
798+
799+ major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
800+ &name, &lifetime, NULL, NULL);
801+ if (major == GSS_S_CREDENTIALS_EXPIRED)
802+ return 0;
803+ else if (GSS_ERROR(major))
804+ return 0;
805+
806+ major = gss_compare_name(&minor, saved_name, name, &equal);
807+ gss_release_name(&minor, &name);
808+ if (GSS_ERROR(major))
809+ return 0;
810+
811+ if (equal && (saved_lifetime < lifetime + now - 10))
812+ return 1;
813+
814+ return 0;
815+}
816+
817 #endif /* GSSAPI */
818diff --git a/gss-serv-krb5.c b/gss-serv-krb5.c
819index 795992d..fd8b371 100644
820--- a/gss-serv-krb5.c
821+++ b/gss-serv-krb5.c
822@@ -1,7 +1,7 @@
823 /* $OpenBSD: gss-serv-krb5.c,v 1.8 2013/07/20 01:55:13 djm Exp $ */
824
825 /*
826- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
827+ * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
828 *
829 * Redistribution and use in source and binary forms, with or without
830 * modification, are permitted provided that the following conditions
831@@ -121,8 +121,8 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
832 krb5_error_code problem;
833 krb5_principal princ;
834 OM_uint32 maj_status, min_status;
835- int len;
836 const char *errmsg;
837+ const char *new_ccname;
838
839 if (client->creds == NULL) {
840 debug("No credentials stored");
841@@ -181,11 +181,16 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
842 return;
843 }
844
845- client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache));
846+ new_ccname = krb5_cc_get_name(krb_context, ccache);
847+
848 client->store.envvar = "KRB5CCNAME";
849- len = strlen(client->store.filename) + 6;
850- client->store.envval = xmalloc(len);
851- snprintf(client->store.envval, len, "FILE:%s", client->store.filename);
852+#ifdef USE_CCAPI
853+ xasprintf(&client->store.envval, "API:%s", new_ccname);
854+ client->store.filename = NULL;
855+#else
856+ xasprintf(&client->store.envval, "FILE:%s", new_ccname);
857+ client->store.filename = xstrdup(new_ccname);
858+#endif
859
860 #ifdef USE_PAM
861 if (options.use_pam)
862@@ -197,6 +202,71 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
863 return;
864 }
865
866+int
867+ssh_gssapi_krb5_updatecreds(ssh_gssapi_ccache *store,
868+ ssh_gssapi_client *client)
869+{
870+ krb5_ccache ccache = NULL;
871+ krb5_principal principal = NULL;
872+ char *name = NULL;
873+ krb5_error_code problem;
874+ OM_uint32 maj_status, min_status;
875+
876+ if ((problem = krb5_cc_resolve(krb_context, store->envval, &ccache))) {
877+ logit("krb5_cc_resolve(): %.100s",
878+ krb5_get_err_text(krb_context, problem));
879+ return 0;
880+ }
881+
882+ /* Find out who the principal in this cache is */
883+ if ((problem = krb5_cc_get_principal(krb_context, ccache,
884+ &principal))) {
885+ logit("krb5_cc_get_principal(): %.100s",
886+ krb5_get_err_text(krb_context, problem));
887+ krb5_cc_close(krb_context, ccache);
888+ return 0;
889+ }
890+
891+ if ((problem = krb5_unparse_name(krb_context, principal, &name))) {
892+ logit("krb5_unparse_name(): %.100s",
893+ krb5_get_err_text(krb_context, problem));
894+ krb5_free_principal(krb_context, principal);
895+ krb5_cc_close(krb_context, ccache);
896+ return 0;
897+ }
898+
899+
900+ if (strcmp(name,client->exportedname.value)!=0) {
901+ debug("Name in local credentials cache differs. Not storing");
902+ krb5_free_principal(krb_context, principal);
903+ krb5_cc_close(krb_context, ccache);
904+ krb5_free_unparsed_name(krb_context, name);
905+ return 0;
906+ }
907+ krb5_free_unparsed_name(krb_context, name);
908+
909+ /* Name matches, so lets get on with it! */
910+
911+ if ((problem = krb5_cc_initialize(krb_context, ccache, principal))) {
912+ logit("krb5_cc_initialize(): %.100s",
913+ krb5_get_err_text(krb_context, problem));
914+ krb5_free_principal(krb_context, principal);
915+ krb5_cc_close(krb_context, ccache);
916+ return 0;
917+ }
918+
919+ krb5_free_principal(krb_context, principal);
920+
921+ if ((maj_status = gss_krb5_copy_ccache(&min_status, client->creds,
922+ ccache))) {
923+ logit("gss_krb5_copy_ccache() failed. Sorry!");
924+ krb5_cc_close(krb_context, ccache);
925+ return 0;
926+ }
927+
928+ return 1;
929+}
930+
931 ssh_gssapi_mech gssapi_kerberos_mech = {
932 "toWM5Slw5Ew8Mqkay+al2g==",
933 "Kerberos",
934@@ -204,7 +274,8 @@ ssh_gssapi_mech gssapi_kerberos_mech = {
935 NULL,
936 &ssh_gssapi_krb5_userok,
937 NULL,
938- &ssh_gssapi_krb5_storecreds
939+ &ssh_gssapi_krb5_storecreds,
940+ &ssh_gssapi_krb5_updatecreds
941 };
942
943 #endif /* KRB5 */
944diff --git a/gss-serv.c b/gss-serv.c
945index 53993d6..2f6baf7 100644
946--- a/gss-serv.c
947+++ b/gss-serv.c
948@@ -1,7 +1,7 @@
949 /* $OpenBSD: gss-serv.c,v 1.29 2015/05/22 03:50:02 djm Exp $ */
950
951 /*
952- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
953+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
954 *
955 * Redistribution and use in source and binary forms, with or without
956 * modification, are permitted provided that the following conditions
957@@ -45,17 +45,22 @@
958 #include "session.h"
959 #include "misc.h"
960 #include "servconf.h"
961+#include "uidswap.h"
962
963 #include "ssh-gss.h"
964+#include "monitor_wrap.h"
965+
966+extern ServerOptions options;
967
968 extern ServerOptions options;
969
970 static ssh_gssapi_client gssapi_client =
971 { GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER,
972- GSS_C_NO_CREDENTIAL, NULL, {NULL, NULL, NULL, NULL}};
973+ GSS_C_NO_CREDENTIAL, GSS_C_NO_NAME, NULL,
974+ {NULL, NULL, NULL, NULL, NULL}, 0, 0};
975
976 ssh_gssapi_mech gssapi_null_mech =
977- { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL};
978+ { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL, NULL};
979
980 #ifdef KRB5
981 extern ssh_gssapi_mech gssapi_kerberos_mech;
982@@ -142,6 +147,29 @@ ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
983 }
984
985 /* Unprivileged */
986+char *
987+ssh_gssapi_server_mechanisms(void) {
988+ gss_OID_set supported;
989+
990+ ssh_gssapi_supported_oids(&supported);
991+ return (ssh_gssapi_kex_mechs(supported, &ssh_gssapi_server_check_mech,
992+ NULL, NULL));
993+}
994+
995+/* Unprivileged */
996+int
997+ssh_gssapi_server_check_mech(Gssctxt **dum, gss_OID oid, const char *data,
998+ const char *dummy) {
999+ Gssctxt *ctx = NULL;
1000+ int res;
1001+
1002+ res = !GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctx, oid)));
1003+ ssh_gssapi_delete_ctx(&ctx);
1004+
1005+ return (res);
1006+}
1007+
1008+/* Unprivileged */
1009 void
1010 ssh_gssapi_supported_oids(gss_OID_set *oidset)
1011 {
1012@@ -151,7 +179,9 @@ ssh_gssapi_supported_oids(gss_OID_set *oidset)
1013 gss_OID_set supported;
1014
1015 gss_create_empty_oid_set(&min_status, oidset);
1016- gss_indicate_mechs(&min_status, &supported);
1017+
1018+ if (GSS_ERROR(gss_indicate_mechs(&min_status, &supported)))
1019+ return;
1020
1021 while (supported_mechs[i]->name != NULL) {
1022 if (GSS_ERROR(gss_test_oid_set_member(&min_status,
1023@@ -277,8 +307,48 @@ OM_uint32
1024 ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
1025 {
1026 int i = 0;
1027+ int equal = 0;
1028+ gss_name_t new_name = GSS_C_NO_NAME;
1029+ gss_buffer_desc ename = GSS_C_EMPTY_BUFFER;
1030+
1031+ if (options.gss_store_rekey && client->used && ctx->client_creds) {
1032+ if (client->mech->oid.length != ctx->oid->length ||
1033+ (memcmp(client->mech->oid.elements,
1034+ ctx->oid->elements, ctx->oid->length) !=0)) {
1035+ debug("Rekeyed credentials have different mechanism");
1036+ return GSS_S_COMPLETE;
1037+ }
1038+
1039+ if ((ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
1040+ ctx->client_creds, ctx->oid, &new_name,
1041+ NULL, NULL, NULL))) {
1042+ ssh_gssapi_error(ctx);
1043+ return (ctx->major);
1044+ }
1045+
1046+ ctx->major = gss_compare_name(&ctx->minor, client->name,
1047+ new_name, &equal);
1048+
1049+ if (GSS_ERROR(ctx->major)) {
1050+ ssh_gssapi_error(ctx);
1051+ return (ctx->major);
1052+ }
1053+
1054+ if (!equal) {
1055+ debug("Rekeyed credentials have different name");
1056+ return GSS_S_COMPLETE;
1057+ }
1058
1059- gss_buffer_desc ename;
1060+ debug("Marking rekeyed credentials for export");
1061+
1062+ gss_release_name(&ctx->minor, &client->name);
1063+ gss_release_cred(&ctx->minor, &client->creds);
1064+ client->name = new_name;
1065+ client->creds = ctx->client_creds;
1066+ ctx->client_creds = GSS_C_NO_CREDENTIAL;
1067+ client->updated = 1;
1068+ return GSS_S_COMPLETE;
1069+ }
1070
1071 client->mech = NULL;
1072
1073@@ -293,6 +363,13 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
1074 if (client->mech == NULL)
1075 return GSS_S_FAILURE;
1076
1077+ if (ctx->client_creds &&
1078+ (ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
1079+ ctx->client_creds, ctx->oid, &client->name, NULL, NULL, NULL))) {
1080+ ssh_gssapi_error(ctx);
1081+ return (ctx->major);
1082+ }
1083+
1084 if ((ctx->major = gss_display_name(&ctx->minor, ctx->client,
1085 &client->displayname, NULL))) {
1086 ssh_gssapi_error(ctx);
1087@@ -310,6 +387,8 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
1088 return (ctx->major);
1089 }
1090
1091+ gss_release_buffer(&ctx->minor, &ename);
1092+
1093 /* We can't copy this structure, so we just move the pointer to it */
1094 client->creds = ctx->client_creds;
1095 ctx->client_creds = GSS_C_NO_CREDENTIAL;
1096@@ -357,7 +436,7 @@ ssh_gssapi_do_child(char ***envp, u_int *envsizep)
1097
1098 /* Privileged */
1099 int
1100-ssh_gssapi_userok(char *user)
1101+ssh_gssapi_userok(char *user, struct passwd *pw)
1102 {
1103 OM_uint32 lmin;
1104
1105@@ -367,9 +446,11 @@ ssh_gssapi_userok(char *user)
1106 return 0;
1107 }
1108 if (gssapi_client.mech && gssapi_client.mech->userok)
1109- if ((*gssapi_client.mech->userok)(&gssapi_client, user))
1110+ if ((*gssapi_client.mech->userok)(&gssapi_client, user)) {
1111+ gssapi_client.used = 1;
1112+ gssapi_client.store.owner = pw;
1113 return 1;
1114- else {
1115+ } else {
1116 /* Destroy delegated credentials if userok fails */
1117 gss_release_buffer(&lmin, &gssapi_client.displayname);
1118 gss_release_buffer(&lmin, &gssapi_client.exportedname);
1119@@ -383,14 +464,90 @@ ssh_gssapi_userok(char *user)
1120 return (0);
1121 }
1122
1123-/* Privileged */
1124-OM_uint32
1125-ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1126+/* These bits are only used for rekeying. The unpriviledged child is running
1127+ * as the user, the monitor is root.
1128+ *
1129+ * In the child, we want to :
1130+ * *) Ask the monitor to store our credentials into the store we specify
1131+ * *) If it succeeds, maybe do a PAM update
1132+ */
1133+
1134+/* Stuff for PAM */
1135+
1136+#ifdef USE_PAM
1137+static int ssh_gssapi_simple_conv(int n, const struct pam_message **msg,
1138+ struct pam_response **resp, void *data)
1139 {
1140- ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
1141- gssbuf, gssmic, NULL);
1142+ return (PAM_CONV_ERR);
1143+}
1144+#endif
1145
1146- return (ctx->major);
1147+void
1148+ssh_gssapi_rekey_creds(void) {
1149+ int ok;
1150+ int ret;
1151+#ifdef USE_PAM
1152+ pam_handle_t *pamh = NULL;
1153+ struct pam_conv pamconv = {ssh_gssapi_simple_conv, NULL};
1154+ char *envstr;
1155+#endif
1156+
1157+ if (gssapi_client.store.filename == NULL &&
1158+ gssapi_client.store.envval == NULL &&
1159+ gssapi_client.store.envvar == NULL)
1160+ return;
1161+
1162+ ok = PRIVSEP(ssh_gssapi_update_creds(&gssapi_client.store));
1163+
1164+ if (!ok)
1165+ return;
1166+
1167+ debug("Rekeyed credentials stored successfully");
1168+
1169+ /* Actually managing to play with the ssh pam stack from here will
1170+ * be next to impossible. In any case, we may want different options
1171+ * for rekeying. So, use our own :)
1172+ */
1173+#ifdef USE_PAM
1174+ if (!use_privsep) {
1175+ debug("Not even going to try and do PAM with privsep disabled");
1176+ return;
1177+ }
1178+
1179+ ret = pam_start("sshd-rekey", gssapi_client.store.owner->pw_name,
1180+ &pamconv, &pamh);
1181+ if (ret)
1182+ return;
1183+
1184+ xasprintf(&envstr, "%s=%s", gssapi_client.store.envvar,
1185+ gssapi_client.store.envval);
1186+
1187+ ret = pam_putenv(pamh, envstr);
1188+ if (!ret)
1189+ pam_setcred(pamh, PAM_REINITIALIZE_CRED);
1190+ pam_end(pamh, PAM_SUCCESS);
1191+#endif
1192+}
1193+
1194+int
1195+ssh_gssapi_update_creds(ssh_gssapi_ccache *store) {
1196+ int ok = 0;
1197+
1198+ /* Check we've got credentials to store */
1199+ if (!gssapi_client.updated)
1200+ return 0;
1201+
1202+ gssapi_client.updated = 0;
1203+
1204+ temporarily_use_uid(gssapi_client.store.owner);
1205+ if (gssapi_client.mech && gssapi_client.mech->updatecreds)
1206+ ok = (*gssapi_client.mech->updatecreds)(store, &gssapi_client);
1207+ else
1208+ debug("No update function for this mechanism");
1209+
1210+ restore_uid();
1211+
1212+ return ok;
1213 }
1214
1215 #endif
1216diff --git a/kex.c b/kex.c
1217index d371f47..913e923 100644
1218--- a/kex.c
1219+++ b/kex.c
1220@@ -54,6 +54,10 @@
1221 #include "sshbuf.h"
1222 #include "digest.h"
1223
1224+#ifdef GSSAPI
1225+#include "ssh-gss.h"
1226+#endif
1227+
1228 #if OPENSSL_VERSION_NUMBER >= 0x00907000L
1229 # if defined(HAVE_EVP_SHA256)
1230 # define evp_ssh_sha256 EVP_sha256
1231@@ -109,6 +113,14 @@ static const struct kexalg kexalgs[] = {
1232 #endif /* HAVE_EVP_SHA256 || !WITH_OPENSSL */
1233 { NULL, -1, -1, -1},
1234 };
1235+static const struct kexalg kexalg_prefixes[] = {
1236+#ifdef GSSAPI
1237+ { KEX_GSS_GEX_SHA1_ID, KEX_GSS_GEX_SHA1, 0, SSH_DIGEST_SHA1 },
1238+ { KEX_GSS_GRP1_SHA1_ID, KEX_GSS_GRP1_SHA1, 0, SSH_DIGEST_SHA1 },
1239+ { KEX_GSS_GRP14_SHA1_ID, KEX_GSS_GRP14_SHA1, 0, SSH_DIGEST_SHA1 },
1240+#endif
1241+ { NULL, -1, -1, -1 },
1242+};
1243
1244 char *
1245 kex_alg_list(char sep)
1246@@ -141,6 +153,10 @@ kex_alg_by_name(const char *name)
1247 if (strcmp(k->name, name) == 0)
1248 return k;
1249 }
1250+ for (k = kexalg_prefixes; k->name != NULL; k++) {
1251+ if (strncmp(k->name, name, strlen(k->name)) == 0)
1252+ return k;
1253+ }
1254 return NULL;
1255 }
1256
1257diff --git a/kex.h b/kex.h
1258index 1c58966..123ef83 100644
1259--- a/kex.h
1260+++ b/kex.h
1261@@ -92,6 +92,9 @@ enum kex_exchange {
1262 KEX_DH_GEX_SHA256,
1263 KEX_ECDH_SHA2,
1264 KEX_C25519_SHA256,
1265+ KEX_GSS_GRP1_SHA1,
1266+ KEX_GSS_GRP14_SHA1,
1267+ KEX_GSS_GEX_SHA1,
1268 KEX_MAX
1269 };
1270
1271@@ -140,6 +143,12 @@ struct kex {
1272 u_int flags;
1273 int hash_alg;
1274 int ec_nid;
1275+#ifdef GSSAPI
1276+ int gss_deleg_creds;
1277+ int gss_trust_dns;
1278+ char *gss_host;
1279+ char *gss_client;
1280+#endif
1281 char *client_version_string;
1282 char *server_version_string;
1283 char *failed_choice;
1284@@ -190,6 +199,11 @@ int kexecdh_server(struct ssh *);
1285 int kexc25519_client(struct ssh *);
1286 int kexc25519_server(struct ssh *);
1287
1288+#ifdef GSSAPI
1289+int kexgss_client(struct ssh *);
1290+int kexgss_server(struct ssh *);
1291+#endif
1292+
1293 int kex_dh_hash(const char *, const char *,
1294 const u_char *, size_t, const u_char *, size_t, const u_char *, size_t,
1295 const BIGNUM *, const BIGNUM *, const BIGNUM *, u_char *, size_t *);
1296diff --git a/kexgssc.c b/kexgssc.c
1297new file mode 100644
1298index 0000000..a49bac2
1299--- /dev/null
1300+++ b/kexgssc.c
1301@@ -0,0 +1,336 @@
1302+/*
1303+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
1304+ *
1305+ * Redistribution and use in source and binary forms, with or without
1306+ * modification, are permitted provided that the following conditions
1307+ * are met:
1308+ * 1. Redistributions of source code must retain the above copyright
1309+ * notice, this list of conditions and the following disclaimer.
1310+ * 2. Redistributions in binary form must reproduce the above copyright
1311+ * notice, this list of conditions and the following disclaimer in the
1312+ * documentation and/or other materials provided with the distribution.
1313+ *
1314+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
1315+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1316+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
1317+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
1318+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
1319+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1320+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1321+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1322+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1323+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1324+ */
1325+
1326+#include "includes.h"
1327+
1328+#ifdef GSSAPI
1329+
1330+#include "includes.h"
1331+
1332+#include <openssl/crypto.h>
1333+#include <openssl/bn.h>
1334+
1335+#include <string.h>
1336+
1337+#include "xmalloc.h"
1338+#include "buffer.h"
1339+#include "ssh2.h"
1340+#include "key.h"
1341+#include "cipher.h"
1342+#include "kex.h"
1343+#include "log.h"
1344+#include "packet.h"
1345+#include "dh.h"
1346+#include "digest.h"
1347+
1348+#include "ssh-gss.h"
1349+
1350+int
1351+kexgss_client(struct ssh *ssh) {
1352+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1353+ gss_buffer_desc recv_tok, gssbuf, msg_tok, *token_ptr;
1354+ Gssctxt *ctxt;
1355+ OM_uint32 maj_status, min_status, ret_flags;
1356+ u_int klen, kout, slen = 0, strlen;
1357+ DH *dh;
1358+ BIGNUM *dh_server_pub = NULL;
1359+ BIGNUM *shared_secret = NULL;
1360+ BIGNUM *p = NULL;
1361+ BIGNUM *g = NULL;
1362+ u_char *kbuf;
1363+ u_char *serverhostkey = NULL;
1364+ u_char *empty = "";
1365+ char *msg;
1366+ int type = 0;
1367+ int first = 1;
1368+ int nbits = 0, min = DH_GRP_MIN, max = DH_GRP_MAX;
1369+ u_char hash[SSH_DIGEST_MAX_LENGTH];
1370+ size_t hashlen;
1371+
1372+ /* Initialise our GSSAPI world */
1373+ ssh_gssapi_build_ctx(&ctxt);
1374+ if (ssh_gssapi_id_kex(ctxt, ssh->kex->name, ssh->kex->kex_type)
1375+ == GSS_C_NO_OID)
1376+ fatal("Couldn't identify host exchange");
1377+
1378+ if (ssh_gssapi_import_name(ctxt, ssh->kex->gss_host))
1379+ fatal("Couldn't import hostname");
1380+
1381+ if (ssh->kex->gss_client &&
1382+ ssh_gssapi_client_identity(ctxt, ssh->kex->gss_client))
1383+ fatal("Couldn't acquire client credentials");
1384+
1385+ switch (ssh->kex->kex_type) {
1386+ case KEX_GSS_GRP1_SHA1:
1387+ dh = dh_new_group1();
1388+ break;
1389+ case KEX_GSS_GRP14_SHA1:
1390+ dh = dh_new_group14();
1391+ break;
1392+ case KEX_GSS_GEX_SHA1:
1393+ debug("Doing group exchange\n");
1394+ nbits = dh_estimate(ssh->kex->we_need * 8);
1395+ packet_start(SSH2_MSG_KEXGSS_GROUPREQ);
1396+ packet_put_int(min);
1397+ packet_put_int(nbits);
1398+ packet_put_int(max);
1399+
1400+ packet_send();
1401+
1402+ packet_read_expect(SSH2_MSG_KEXGSS_GROUP);
1403+
1404+ if ((p = BN_new()) == NULL)
1405+ fatal("BN_new() failed");
1406+ packet_get_bignum2(p);
1407+ if ((g = BN_new()) == NULL)
1408+ fatal("BN_new() failed");
1409+ packet_get_bignum2(g);
1410+ packet_check_eom();
1411+
1412+ if (BN_num_bits(p) < min || BN_num_bits(p) > max)
1413+ fatal("GSSGRP_GEX group out of range: %d !< %d !< %d",
1414+ min, BN_num_bits(p), max);
1415+
1416+ dh = dh_new_group(g, p);
1417+ break;
1418+ default:
1419+ fatal("%s: Unexpected KEX type %d", __func__, ssh->kex->kex_type);
1420+ }
1421+
1422+ /* Step 1 - e is dh->pub_key */
1423+ dh_gen_key(dh, ssh->kex->we_need * 8);
1424+
1425+ /* This is f, we initialise it now to make life easier */
1426+ dh_server_pub = BN_new();
1427+ if (dh_server_pub == NULL)
1428+ fatal("dh_server_pub == NULL");
1429+
1430+ token_ptr = GSS_C_NO_BUFFER;
1431+
1432+ do {
1433+ debug("Calling gss_init_sec_context");
1434+
1435+ maj_status = ssh_gssapi_init_ctx(ctxt,
1436+ ssh->kex->gss_deleg_creds, token_ptr, &send_tok,
1437+ &ret_flags);
1438+
1439+ if (GSS_ERROR(maj_status)) {
1440+ if (send_tok.length != 0) {
1441+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1442+ packet_put_string(send_tok.value,
1443+ send_tok.length);
1444+ }
1445+ fatal("gss_init_context failed");
1446+ }
1447+
1448+ /* If we've got an old receive buffer get rid of it */
1449+ if (token_ptr != GSS_C_NO_BUFFER)
1450+ free(recv_tok.value);
1451+
1452+ if (maj_status == GSS_S_COMPLETE) {
1453+ /* If mutual state flag is not true, kex fails */
1454+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
1455+ fatal("Mutual authentication failed");
1456+
1457+ /* If integ avail flag is not true kex fails */
1458+ if (!(ret_flags & GSS_C_INTEG_FLAG))
1459+ fatal("Integrity check failed");
1460+ }
1461+
1462+ /*
1463+ * If we have data to send, then the last message that we
1464+ * received cannot have been a 'complete'.
1465+ */
1466+ if (send_tok.length != 0) {
1467+ if (first) {
1468+ packet_start(SSH2_MSG_KEXGSS_INIT);
1469+ packet_put_string(send_tok.value,
1470+ send_tok.length);
1471+ packet_put_bignum2(dh->pub_key);
1472+ first = 0;
1473+ } else {
1474+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1475+ packet_put_string(send_tok.value,
1476+ send_tok.length);
1477+ }
1478+ packet_send();
1479+ gss_release_buffer(&min_status, &send_tok);
1480+
1481+ /* If we've sent them data, they should reply */
1482+ do {
1483+ type = packet_read();
1484+ if (type == SSH2_MSG_KEXGSS_HOSTKEY) {
1485+ debug("Received KEXGSS_HOSTKEY");
1486+ if (serverhostkey)
1487+ fatal("Server host key received more than once");
1488+ serverhostkey =
1489+ packet_get_string(&slen);
1490+ }
1491+ } while (type == SSH2_MSG_KEXGSS_HOSTKEY);
1492+
1493+ switch (type) {
1494+ case SSH2_MSG_KEXGSS_CONTINUE:
1495+ debug("Received GSSAPI_CONTINUE");
1496+ if (maj_status == GSS_S_COMPLETE)
1497+ fatal("GSSAPI Continue received from server when complete");
1498+ recv_tok.value = packet_get_string(&strlen);
1499+ recv_tok.length = strlen;
1500+ break;
1501+ case SSH2_MSG_KEXGSS_COMPLETE:
1502+ debug("Received GSSAPI_COMPLETE");
1503+ packet_get_bignum2(dh_server_pub);
1504+ msg_tok.value = packet_get_string(&strlen);
1505+ msg_tok.length = strlen;
1506+
1507+ /* Is there a token included? */
1508+ if (packet_get_char()) {
1509+ recv_tok.value=
1510+ packet_get_string(&strlen);
1511+ recv_tok.length = strlen;
1512+ /* If we're already complete - protocol error */
1513+ if (maj_status == GSS_S_COMPLETE)
1514+ packet_disconnect("Protocol error: received token when complete");
1515+ } else {
1516+ /* No token included */
1517+ if (maj_status != GSS_S_COMPLETE)
1518+ packet_disconnect("Protocol error: did not receive final token");
1519+ }
1520+ break;
1521+ case SSH2_MSG_KEXGSS_ERROR:
1522+ debug("Received Error");
1523+ maj_status = packet_get_int();
1524+ min_status = packet_get_int();
1525+ msg = packet_get_string(NULL);
1526+ (void) packet_get_string_ptr(NULL);
1527+ fatal("GSSAPI Error: \n%.400s",msg);
1528+ default:
1529+ packet_disconnect("Protocol error: didn't expect packet type %d",
1530+ type);
1531+ }
1532+ token_ptr = &recv_tok;
1533+ } else {
1534+ /* No data, and not complete */
1535+ if (maj_status != GSS_S_COMPLETE)
1536+ fatal("Not complete, and no token output");
1537+ }
1538+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
1539+
1540+ /*
1541+ * We _must_ have received a COMPLETE message in reply from the
1542+ * server, which will have set dh_server_pub and msg_tok
1543+ */
1544+
1545+ if (type != SSH2_MSG_KEXGSS_COMPLETE)
1546+ fatal("Didn't receive a SSH2_MSG_KEXGSS_COMPLETE when I expected it");
1547+
1548+ /* Check f in range [1, p-1] */
1549+ if (!dh_pub_is_valid(dh, dh_server_pub))
1550+ packet_disconnect("bad server public DH value");
1551+
1552+ /* compute K=f^x mod p */
1553+ klen = DH_size(dh);
1554+ kbuf = xmalloc(klen);
1555+ kout = DH_compute_key(kbuf, dh_server_pub, dh);
1556+ if (kout < 0)
1557+ fatal("DH_compute_key: failed");
1558+
1559+ shared_secret = BN_new();
1560+ if (shared_secret == NULL)
1561+ fatal("kexgss_client: BN_new failed");
1562+
1563+ if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
1564+ fatal("kexdh_client: BN_bin2bn failed");
1565+
1566+ memset(kbuf, 0, klen);
1567+ free(kbuf);
1568+
1569+ hashlen = sizeof(hash);
1570+ switch (ssh->kex->kex_type) {
1571+ case KEX_GSS_GRP1_SHA1:
1572+ case KEX_GSS_GRP14_SHA1:
1573+ kex_dh_hash( ssh->kex->client_version_string,
1574+ ssh->kex->server_version_string,
1575+ buffer_ptr(ssh->kex->my), buffer_len(ssh->kex->my),
1576+ buffer_ptr(ssh->kex->peer), buffer_len(ssh->kex->peer),
1577+ (serverhostkey ? serverhostkey : empty), slen,
1578+ dh->pub_key, /* e */
1579+ dh_server_pub, /* f */
1580+ shared_secret, /* K */
1581+ hash, &hashlen
1582+ );
1583+ break;
1584+ case KEX_GSS_GEX_SHA1:
1585+ kexgex_hash(
1586+ ssh->kex->hash_alg,
1587+ ssh->kex->client_version_string,
1588+ ssh->kex->server_version_string,
1589+ buffer_ptr(ssh->kex->my), buffer_len(ssh->kex->my),
1590+ buffer_ptr(ssh->kex->peer), buffer_len(ssh->kex->peer),
1591+ (serverhostkey ? serverhostkey : empty), slen,
1592+ min, nbits, max,
1593+ dh->p, dh->g,
1594+ dh->pub_key,
1595+ dh_server_pub,
1596+ shared_secret,
1597+ hash, &hashlen
1598+ );
1599+ break;
1600+ default:
1601+ fatal("%s: Unexpected KEX type %d", __func__, ssh->kex->kex_type);
1602+ }
1603+
1604+ gssbuf.value = hash;
1605+ gssbuf.length = hashlen;
1606+
1607+ /* Verify that the hash matches the MIC we just got. */
1608+ if (GSS_ERROR(ssh_gssapi_checkmic(ctxt, &gssbuf, &msg_tok)))
1609+ packet_disconnect("Hash's MIC didn't verify");
1610+
1611+ free(msg_tok.value);
1612+
1613+ DH_free(dh);
1614+ free(serverhostkey);
1615+ BN_clear_free(dh_server_pub);
1616+
1617+ /* save session id */
1618+ if (ssh->kex->session_id == NULL) {
1619+ ssh->kex->session_id_len = hashlen;
1620+ ssh->kex->session_id = xmalloc(ssh->kex->session_id_len);
1621+ memcpy(ssh->kex->session_id, hash, ssh->kex->session_id_len);
1622+ }
1623+
1624+ if (ssh->kex->gss_deleg_creds)
1625+ ssh_gssapi_credentials_updated(ctxt);
1626+
1627+ if (gss_kex_context == NULL)
1628+ gss_kex_context = ctxt;
1629+ else
1630+ ssh_gssapi_delete_ctx(&ctxt);
1631+
1632+ kex_derive_keys_bn(ssh, hash, hashlen, shared_secret);
1633+ BN_clear_free(shared_secret);
1634+ return kex_send_newkeys(ssh);
1635+}
1636+
1637+#endif /* GSSAPI */
1638diff --git a/kexgsss.c b/kexgsss.c
1639new file mode 100644
1640index 0000000..0847469
1641--- /dev/null
1642+++ b/kexgsss.c
1643@@ -0,0 +1,295 @@
1644+/*
1645+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
1646+ *
1647+ * Redistribution and use in source and binary forms, with or without
1648+ * modification, are permitted provided that the following conditions
1649+ * are met:
1650+ * 1. Redistributions of source code must retain the above copyright
1651+ * notice, this list of conditions and the following disclaimer.
1652+ * 2. Redistributions in binary form must reproduce the above copyright
1653+ * notice, this list of conditions and the following disclaimer in the
1654+ * documentation and/or other materials provided with the distribution.
1655+ *
1656+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
1657+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1658+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
1659+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
1660+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
1661+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1662+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1663+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1664+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1665+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1666+ */
1667+
1668+#include "includes.h"
1669+
1670+#ifdef GSSAPI
1671+
1672+#include <string.h>
1673+
1674+#include <openssl/crypto.h>
1675+#include <openssl/bn.h>
1676+
1677+#include "xmalloc.h"
1678+#include "buffer.h"
1679+#include "ssh2.h"
1680+#include "key.h"
1681+#include "cipher.h"
1682+#include "kex.h"
1683+#include "log.h"
1684+#include "packet.h"
1685+#include "dh.h"
1686+#include "ssh-gss.h"
1687+#include "monitor_wrap.h"
1688+#include "misc.h"
1689+#include "servconf.h"
1690+#include "digest.h"
1691+
1692+extern ServerOptions options;
1693+
1694+int
1695+kexgss_server(struct ssh *ssh)
1696+{
1697+ OM_uint32 maj_status, min_status;
1698+
1699+ /*
1700+ * Some GSSAPI implementations use the input value of ret_flags (an
1701+ * output variable) as a means of triggering mechanism specific
1702+ * features. Initializing it to zero avoids inadvertently
1703+ * activating this non-standard behaviour.
1704+ */
1705+
1706+ OM_uint32 ret_flags = 0;
1707+ gss_buffer_desc gssbuf, recv_tok, msg_tok;
1708+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1709+ Gssctxt *ctxt = NULL;
1710+ u_int slen, klen, kout;
1711+ u_char *kbuf;
1712+ DH *dh;
1713+ int min = -1, max = -1, nbits = -1;
1714+ BIGNUM *shared_secret = NULL;
1715+ BIGNUM *dh_client_pub = NULL;
1716+ int type = 0;
1717+ gss_OID oid;
1718+ char *mechs;
1719+ u_char hash[SSH_DIGEST_MAX_LENGTH];
1720+ size_t hashlen;
1721+
1722+ /* Initialise GSSAPI */
1723+
1724+ /* If we're rekeying, privsep means that some of the private structures
1725+ * in the GSSAPI code are no longer available. This kludges them back
1726+ * into life
1727+ */
1728+ if (!ssh_gssapi_oid_table_ok()) {
1729+ mechs = ssh_gssapi_server_mechanisms();
1730+ free(mechs);
1731+ }
1732+
1733+ debug2("%s: Identifying %s", __func__, ssh->kex->name);
1734+ oid = ssh_gssapi_id_kex(NULL, ssh->kex->name, ssh->kex->kex_type);
1735+ if (oid == GSS_C_NO_OID)
1736+ fatal("Unknown gssapi mechanism");
1737+
1738+ debug2("%s: Acquiring credentials", __func__);
1739+
1740+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctxt, oid))))
1741+ fatal("Unable to acquire credentials for the server");
1742+
1743+ switch (ssh->kex->kex_type) {
1744+ case KEX_GSS_GRP1_SHA1:
1745+ dh = dh_new_group1();
1746+ break;
1747+ case KEX_GSS_GRP14_SHA1:
1748+ dh = dh_new_group14();
1749+ break;
1750+ case KEX_GSS_GEX_SHA1:
1751+ debug("Doing group exchange");
1752+ packet_read_expect(SSH2_MSG_KEXGSS_GROUPREQ);
1753+ min = packet_get_int();
1754+ nbits = packet_get_int();
1755+ max = packet_get_int();
1756+ min = MAX(DH_GRP_MIN, min);
1757+ max = MIN(DH_GRP_MAX, max);
1758+ packet_check_eom();
1759+ if (max < min || nbits < min || max < nbits)
1760+ fatal("GSS_GEX, bad parameters: %d !< %d !< %d",
1761+ min, nbits, max);
1762+ dh = PRIVSEP(choose_dh(min, nbits, max));
1763+ if (dh == NULL)
1764+ packet_disconnect("Protocol error: no matching group found");
1765+
1766+ packet_start(SSH2_MSG_KEXGSS_GROUP);
1767+ packet_put_bignum2(dh->p);
1768+ packet_put_bignum2(dh->g);
1769+ packet_send();
1770+
1771+ packet_write_wait();
1772+ break;
1773+ default:
1774+ fatal("%s: Unexpected KEX type %d", __func__, ssh->kex->kex_type);
1775+ }
1776+
1777+ dh_gen_key(dh, ssh->kex->we_need * 8);
1778+
1779+ do {
1780+ debug("Wait SSH2_MSG_GSSAPI_INIT");
1781+ type = packet_read();
1782+ switch(type) {
1783+ case SSH2_MSG_KEXGSS_INIT:
1784+ if (dh_client_pub != NULL)
1785+ fatal("Received KEXGSS_INIT after initialising");
1786+ recv_tok.value = packet_get_string(&slen);
1787+ recv_tok.length = slen;
1788+
1789+ if ((dh_client_pub = BN_new()) == NULL)
1790+ fatal("dh_client_pub == NULL");
1791+
1792+ packet_get_bignum2(dh_client_pub);
1793+
1794+ /* Send SSH_MSG_KEXGSS_HOSTKEY here, if we want */
1795+ break;
1796+ case SSH2_MSG_KEXGSS_CONTINUE:
1797+ recv_tok.value = packet_get_string(&slen);
1798+ recv_tok.length = slen;
1799+ break;
1800+ default:
1801+ packet_disconnect(
1802+ "Protocol error: didn't expect packet type %d",
1803+ type);
1804+ }
1805+
1806+ maj_status = PRIVSEP(ssh_gssapi_accept_ctx(ctxt, &recv_tok,
1807+ &send_tok, &ret_flags));
1808+
1809+ free(recv_tok.value);
1810+
1811+ if (maj_status != GSS_S_COMPLETE && send_tok.length == 0)
1812+ fatal("Zero length token output when incomplete");
1813+
1814+ if (dh_client_pub == NULL)
1815+ fatal("No client public key");
1816+
1817+ if (maj_status & GSS_S_CONTINUE_NEEDED) {
1818+ debug("Sending GSSAPI_CONTINUE");
1819+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1820+ packet_put_string(send_tok.value, send_tok.length);
1821+ packet_send();
1822+ gss_release_buffer(&min_status, &send_tok);
1823+ }
1824+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
1825+
1826+ if (GSS_ERROR(maj_status)) {
1827+ if (send_tok.length > 0) {
1828+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
1829+ packet_put_string(send_tok.value, send_tok.length);
1830+ packet_send();
1831+ }
1832+ fatal("accept_ctx died");
1833+ }
1834+
1835+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
1836+ fatal("Mutual Authentication flag wasn't set");
1837+
1838+ if (!(ret_flags & GSS_C_INTEG_FLAG))
1839+ fatal("Integrity flag wasn't set");
1840+
1841+ if (!dh_pub_is_valid(dh, dh_client_pub))
1842+ packet_disconnect("bad client public DH value");
1843+
1844+ klen = DH_size(dh);
1845+ kbuf = xmalloc(klen);
1846+ kout = DH_compute_key(kbuf, dh_client_pub, dh);
1847+ if (kout < 0)
1848+ fatal("DH_compute_key: failed");
1849+
1850+ shared_secret = BN_new();
1851+ if (shared_secret == NULL)
1852+ fatal("kexgss_server: BN_new failed");
1853+
1854+ if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
1855+ fatal("kexgss_server: BN_bin2bn failed");
1856+
1857+ memset(kbuf, 0, klen);
1858+ free(kbuf);
1859+
1860+ hashlen = sizeof(hash);
1861+ switch (ssh->kex->kex_type) {
1862+ case KEX_GSS_GRP1_SHA1:
1863+ case KEX_GSS_GRP14_SHA1:
1864+ kex_dh_hash(
1865+ ssh->kex->client_version_string, ssh->kex->server_version_string,
1866+ buffer_ptr(ssh->kex->peer), buffer_len(ssh->kex->peer),
1867+ buffer_ptr(ssh->kex->my), buffer_len(ssh->kex->my),
1868+ NULL, 0, /* Change this if we start sending host keys */
1869+ dh_client_pub, dh->pub_key, shared_secret,
1870+ hash, &hashlen
1871+ );
1872+ break;
1873+ case KEX_GSS_GEX_SHA1:
1874+ kexgex_hash(
1875+ ssh->kex->hash_alg,
1876+ ssh->kex->client_version_string, ssh->kex->server_version_string,
1877+ buffer_ptr(ssh->kex->peer), buffer_len(ssh->kex->peer),
1878+ buffer_ptr(ssh->kex->my), buffer_len(ssh->kex->my),
1879+ NULL, 0,
1880+ min, nbits, max,
1881+ dh->p, dh->g,
1882+ dh_client_pub,
1883+ dh->pub_key,
1884+ shared_secret,
1885+ hash, &hashlen
1886+ );
1887+ break;
1888+ default:
1889+ fatal("%s: Unexpected KEX type %d", __func__, ssh->kex->kex_type);
1890+ }
1891+
1892+ BN_clear_free(dh_client_pub);
1893+
1894+ if (ssh->kex->session_id == NULL) {
1895+ ssh->kex->session_id_len = hashlen;
1896+ ssh->kex->session_id = xmalloc(ssh->kex->session_id_len);
1897+ memcpy(ssh->kex->session_id, hash, ssh->kex->session_id_len);
1898+ }
1899+
1900+ gssbuf.value = hash;
1901+ gssbuf.length = hashlen;
1902+
1903+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_sign(ctxt,&gssbuf,&msg_tok))))
1904+ fatal("Couldn't get MIC");
1905+
1906+ packet_start(SSH2_MSG_KEXGSS_COMPLETE);
1907+ packet_put_bignum2(dh->pub_key);
1908+ packet_put_string(msg_tok.value,msg_tok.length);
1909+
1910+ if (send_tok.length != 0) {
1911+ packet_put_char(1); /* true */
1912+ packet_put_string(send_tok.value, send_tok.length);
1913+ } else {
1914+ packet_put_char(0); /* false */
1915+ }
1916+ packet_send();
1917+
1918+ gss_release_buffer(&min_status, &send_tok);
1919+ gss_release_buffer(&min_status, &msg_tok);
1920+
1921+ if (gss_kex_context == NULL)
1922+ gss_kex_context = ctxt;
1923+ else
1924+ ssh_gssapi_delete_ctx(&ctxt);
1925+
1926+ DH_free(dh);
1927+
1928+ kex_derive_keys_bn(ssh, hash, hashlen, shared_secret);
1929+ BN_clear_free(shared_secret);
1930+ kex_send_newkeys(ssh);
1931+
1932+ /* If this was a rekey, then save out any delegated credentials we
1933+ * just exchanged. */
1934+ if (options.gss_store_rekey)
1935+ ssh_gssapi_rekey_creds();
1936+ return 0;
1937+}
1938+#endif /* GSSAPI */
1939diff --git a/monitor.c b/monitor.c
1940index ac7dd30..6c82023 100644
1941--- a/monitor.c
1942+++ b/monitor.c
1943@@ -156,6 +156,8 @@ int mm_answer_gss_setup_ctx(int, Buffer *);
1944 int mm_answer_gss_accept_ctx(int, Buffer *);
1945 int mm_answer_gss_userok(int, Buffer *);
1946 int mm_answer_gss_checkmic(int, Buffer *);
1947+int mm_answer_gss_sign(int, Buffer *);
1948+int mm_answer_gss_updatecreds(int, Buffer *);
1949 #endif
1950
1951 #ifdef SSH_AUDIT_EVENTS
1952@@ -233,11 +235,18 @@ struct mon_table mon_dispatch_proto20[] = {
1953 {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
1954 {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1955 {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1956+ {MONITOR_REQ_GSSSIGN, MON_ONCE, mm_answer_gss_sign},
1957 #endif
1958 {0, 0, NULL}
1959 };
1960
1961 struct mon_table mon_dispatch_postauth20[] = {
1962+#ifdef GSSAPI
1963+ {MONITOR_REQ_GSSSETUP, 0, mm_answer_gss_setup_ctx},
1964+ {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
1965+ {MONITOR_REQ_GSSSIGN, 0, mm_answer_gss_sign},
1966+ {MONITOR_REQ_GSSUPCREDS, 0, mm_answer_gss_updatecreds},
1967+#endif
1968 #ifdef WITH_OPENSSL
1969 {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
1970 #endif
1971@@ -352,6 +361,10 @@ monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1972 /* Permit requests for moduli and signatures */
1973 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
1974 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1975+#ifdef GSSAPI
1976+ /* and for the GSSAPI key exchange */
1977+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
1978+#endif
1979 } else {
1980 mon_dispatch = mon_dispatch_proto15;
1981
1982@@ -460,6 +473,10 @@ monitor_child_postauth(struct monitor *pmonitor)
1983 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
1984 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1985 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1986+#ifdef GSSAPI
1987+ /* and for the GSSAPI key exchange */
1988+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
1989+#endif
1990 } else {
1991 mon_dispatch = mon_dispatch_postauth15;
1992 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1993@@ -1861,6 +1878,13 @@ monitor_apply_keystate(struct monitor *pmonitor)
1994 # endif
1995 #endif /* WITH_OPENSSL */
1996 kex->kex[KEX_C25519_SHA256] = kexc25519_server;
1997+#ifdef GSSAPI
1998+ if (options.gss_keyex) {
1999+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
2000+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
2001+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_server;
2002+ }
2003+#endif
2004 kex->load_host_public_key=&get_hostkey_public_by_type;
2005 kex->load_host_private_key=&get_hostkey_private_by_type;
2006 kex->host_key_index=&get_hostkey_index;
2007@@ -1960,6 +1984,9 @@ mm_answer_gss_setup_ctx(int sock, Buffer *m)
2008 OM_uint32 major;
2009 u_int len;
2010
2011+ if (!options.gss_authentication && !options.gss_keyex)
2012+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2013+
2014 goid.elements = buffer_get_string(m, &len);
2015 goid.length = len;
2016
2017@@ -1987,6 +2014,9 @@ mm_answer_gss_accept_ctx(int sock, Buffer *m)
2018 OM_uint32 flags = 0; /* GSI needs this */
2019 u_int len;
2020
2021+ if (!options.gss_authentication && !options.gss_keyex)
2022+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2023+
2024 in.value = buffer_get_string(m, &len);
2025 in.length = len;
2026 major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
2027@@ -2004,6 +2034,7 @@ mm_answer_gss_accept_ctx(int sock, Buffer *m)
2028 monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
2029 monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
2030 monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
2031+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSIGN, 1);
2032 }
2033 return (0);
2034 }
2035@@ -2015,6 +2046,9 @@ mm_answer_gss_checkmic(int sock, Buffer *m)
2036 OM_uint32 ret;
2037 u_int len;
2038
2039+ if (!options.gss_authentication && !options.gss_keyex)
2040+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2041+
2042 gssbuf.value = buffer_get_string(m, &len);
2043 gssbuf.length = len;
2044 mic.value = buffer_get_string(m, &len);
2045@@ -2041,7 +2075,11 @@ mm_answer_gss_userok(int sock, Buffer *m)
2046 {
2047 int authenticated;
2048
2049- authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
2050+ if (!options.gss_authentication && !options.gss_keyex)
2051+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2052+
2053+ authenticated = authctxt->valid &&
2054+ ssh_gssapi_userok(authctxt->user, authctxt->pw);
2055
2056 buffer_clear(m);
2057 buffer_put_int(m, authenticated);
2058@@ -2054,5 +2092,73 @@ mm_answer_gss_userok(int sock, Buffer *m)
2059 /* Monitor loop will terminate if authenticated */
2060 return (authenticated);
2061 }
2062+
2063+int
2064+mm_answer_gss_sign(int socket, Buffer *m)
2065+{
2066+ gss_buffer_desc data;
2067+ gss_buffer_desc hash = GSS_C_EMPTY_BUFFER;
2068+ OM_uint32 major, minor;
2069+ u_int len;
2070+
2071+ if (!options.gss_authentication && !options.gss_keyex)
2072+ fatal("In GSSAPI monitor when GSSAPI is disabled");
2073+
2074+ data.value = buffer_get_string(m, &len);
2075+ data.length = len;
2076+ if (data.length != 20)
2077+ fatal("%s: data length incorrect: %d", __func__,
2078+ (int) data.length);
2079+
2080+ /* Save the session ID on the first time around */
2081+ if (session_id2_len == 0) {
2082+ session_id2_len = data.length;
2083+ session_id2 = xmalloc(session_id2_len);
2084+ memcpy(session_id2, data.value, session_id2_len);
2085+ }
2086+ major = ssh_gssapi_sign(gsscontext, &data, &hash);
2087+
2088+ free(data.value);
2089+
2090+ buffer_clear(m);
2091+ buffer_put_int(m, major);
2092+ buffer_put_string(m, hash.value, hash.length);
2093+
2094+ mm_request_send(socket, MONITOR_ANS_GSSSIGN, m);
2095+
2096+ gss_release_buffer(&minor, &hash);
2097+
2098+ /* Turn on getpwnam permissions */
2099+ monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
2100+
2101+ /* And credential updating, for when rekeying */
2102+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSUPCREDS, 1);
2103+
2104+ return (0);
2105+}
2106+
2107+int
2108+mm_answer_gss_updatecreds(int socket, Buffer *m) {
2109+ ssh_gssapi_ccache store;
2110+ int ok;
2111+
2112+ store.filename = buffer_get_string(m, NULL);
2113+ store.envvar = buffer_get_string(m, NULL);
2114+ store.envval = buffer_get_string(m, NULL);
2115+
2116+ ok = ssh_gssapi_update_creds(&store);
2117+
2118+ free(store.filename);
2119+ free(store.envvar);
2120+ free(store.envval);
2121+
2122+ buffer_clear(m);
2123+ buffer_put_int(m, ok);
2124+
2125+ mm_request_send(socket, MONITOR_ANS_GSSUPCREDS, m);
2126+
2127+ return(0);
2128+}
2129+
2130 #endif /* GSSAPI */
2131
2132diff --git a/monitor.h b/monitor.h
2133index 93b8b66..bc50ade 100644
2134--- a/monitor.h
2135+++ b/monitor.h
2136@@ -65,6 +65,9 @@ enum monitor_reqtype {
2137 MONITOR_REQ_PAM_FREE_CTX = 110, MONITOR_ANS_PAM_FREE_CTX = 111,
2138 MONITOR_REQ_AUDIT_EVENT = 112, MONITOR_REQ_AUDIT_COMMAND = 113,
2139
2140+ MONITOR_REQ_GSSSIGN = 150, MONITOR_ANS_GSSSIGN = 151,
2141+ MONITOR_REQ_GSSUPCREDS = 152, MONITOR_ANS_GSSUPCREDS = 153,
2142+
2143 };
2144
2145 struct mm_master;
2146diff --git a/monitor_wrap.c b/monitor_wrap.c
2147index c5db6df..74fbd2e 100644
2148--- a/monitor_wrap.c
2149+++ b/monitor_wrap.c
2150@@ -1068,7 +1068,7 @@ mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
2151 }
2152
2153 int
2154-mm_ssh_gssapi_userok(char *user)
2155+mm_ssh_gssapi_userok(char *user, struct passwd *pw)
2156 {
2157 Buffer m;
2158 int authenticated = 0;
2159@@ -1085,5 +1085,50 @@ mm_ssh_gssapi_userok(char *user)
2160 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
2161 return (authenticated);
2162 }
2163+
2164+OM_uint32
2165+mm_ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_desc *data, gss_buffer_desc *hash)
2166+{
2167+ Buffer m;
2168+ OM_uint32 major;
2169+ u_int len;
2170+
2171+ buffer_init(&m);
2172+ buffer_put_string(&m, data->value, data->length);
2173+
2174+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSIGN, &m);
2175+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSIGN, &m);
2176+
2177+ major = buffer_get_int(&m);
2178+ hash->value = buffer_get_string(&m, &len);
2179+ hash->length = len;
2180+
2181+ buffer_free(&m);
2182+
2183+ return(major);
2184+}
2185+
2186+int
2187+mm_ssh_gssapi_update_creds(ssh_gssapi_ccache *store)
2188+{
2189+ Buffer m;
2190+ int ok;
2191+
2192+ buffer_init(&m);
2193+
2194+ buffer_put_cstring(&m, store->filename ? store->filename : "");
2195+ buffer_put_cstring(&m, store->envvar ? store->envvar : "");
2196+ buffer_put_cstring(&m, store->envval ? store->envval : "");
2197+
2198+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUPCREDS, &m);
2199+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUPCREDS, &m);
2200+
2201+ ok = buffer_get_int(&m);
2202+
2203+ buffer_free(&m);
2204+
2205+ return (ok);
2206+}
2207+
2208 #endif /* GSSAPI */
2209
2210diff --git a/monitor_wrap.h b/monitor_wrap.h
2211index eb820ae..403f8d0 100644
2212--- a/monitor_wrap.h
2213+++ b/monitor_wrap.h
2214@@ -58,8 +58,10 @@ BIGNUM *mm_auth_rsa_generate_challenge(Key *);
2215 OM_uint32 mm_ssh_gssapi_server_ctx(Gssctxt **, gss_OID);
2216 OM_uint32 mm_ssh_gssapi_accept_ctx(Gssctxt *,
2217 gss_buffer_desc *, gss_buffer_desc *, OM_uint32 *);
2218-int mm_ssh_gssapi_userok(char *user);
2219+int mm_ssh_gssapi_userok(char *user, struct passwd *);
2220 OM_uint32 mm_ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
2221+OM_uint32 mm_ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
2222+int mm_ssh_gssapi_update_creds(ssh_gssapi_ccache *);
2223 #endif
2224
2225 #ifdef USE_PAM
2226diff --git a/readconf.c b/readconf.c
2227index 69d4553..d2a3d4b 100644
2228--- a/readconf.c
2229+++ b/readconf.c
2230@@ -148,6 +148,8 @@ typedef enum {
2231 oClearAllForwardings, oNoHostAuthenticationForLocalhost,
2232 oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout,
2233 oAddressFamily, oGssAuthentication, oGssDelegateCreds,
2234+ oGssTrustDns, oGssKeyEx, oGssClientIdentity, oGssRenewalRekey,
2235+ oGssServerIdentity,
2236 oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly,
2237 oSendEnv, oControlPath, oControlMaster, oControlPersist,
2238 oHashKnownHosts,
2239@@ -193,10 +195,19 @@ static struct {
2240 { "afstokenpassing", oUnsupported },
2241 #if defined(GSSAPI)
2242 { "gssapiauthentication", oGssAuthentication },
2243+ { "gssapikeyexchange", oGssKeyEx },
2244 { "gssapidelegatecredentials", oGssDelegateCreds },
2245+ { "gssapitrustdns", oGssTrustDns },
2246+ { "gssapiclientidentity", oGssClientIdentity },
2247+ { "gssapiserveridentity", oGssServerIdentity },
2248+ { "gssapirenewalforcesrekey", oGssRenewalRekey },
2249 #else
2250 { "gssapiauthentication", oUnsupported },
2251+ { "gssapikeyexchange", oUnsupported },
2252 { "gssapidelegatecredentials", oUnsupported },
2253+ { "gssapitrustdns", oUnsupported },
2254+ { "gssapiclientidentity", oUnsupported },
2255+ { "gssapirenewalforcesrekey", oUnsupported },
2256 #endif
2257 { "fallbacktorsh", oDeprecated },
2258 { "usersh", oDeprecated },
2259@@ -926,10 +937,30 @@ parse_time:
2260 intptr = &options->gss_authentication;
2261 goto parse_flag;
2262
2263+ case oGssKeyEx:
2264+ intptr = &options->gss_keyex;
2265+ goto parse_flag;
2266+
2267 case oGssDelegateCreds:
2268 intptr = &options->gss_deleg_creds;
2269 goto parse_flag;
2270
2271+ case oGssTrustDns:
2272+ intptr = &options->gss_trust_dns;
2273+ goto parse_flag;
2274+
2275+ case oGssClientIdentity:
2276+ charptr = &options->gss_client_identity;
2277+ goto parse_string;
2278+
2279+ case oGssServerIdentity:
2280+ charptr = &options->gss_server_identity;
2281+ goto parse_string;
2282+
2283+ case oGssRenewalRekey:
2284+ intptr = &options->gss_renewal_rekey;
2285+ goto parse_flag;
2286+
2287 case oBatchMode:
2288 intptr = &options->batch_mode;
2289 goto parse_flag;
2290@@ -1648,7 +1679,12 @@ initialize_options(Options * options)
2291 options->pubkey_authentication = -1;
2292 options->challenge_response_authentication = -1;
2293 options->gss_authentication = -1;
2294+ options->gss_keyex = -1;
2295 options->gss_deleg_creds = -1;
2296+ options->gss_trust_dns = -1;
2297+ options->gss_renewal_rekey = -1;
2298+ options->gss_client_identity = NULL;
2299+ options->gss_server_identity = NULL;
2300 options->password_authentication = -1;
2301 options->kbd_interactive_authentication = -1;
2302 options->kbd_interactive_devices = NULL;
2303@@ -1777,8 +1813,14 @@ fill_default_options(Options * options)
2304 options->challenge_response_authentication = 1;
2305 if (options->gss_authentication == -1)
2306 options->gss_authentication = 0;
2307+ if (options->gss_keyex == -1)
2308+ options->gss_keyex = 0;
2309 if (options->gss_deleg_creds == -1)
2310 options->gss_deleg_creds = 0;
2311+ if (options->gss_trust_dns == -1)
2312+ options->gss_trust_dns = 0;
2313+ if (options->gss_renewal_rekey == -1)
2314+ options->gss_renewal_rekey = 0;
2315 if (options->password_authentication == -1)
2316 options->password_authentication = 1;
2317 if (options->kbd_interactive_authentication == -1)
2318diff --git a/readconf.h b/readconf.h
2319index c84d068..37a0555 100644
2320--- a/readconf.h
2321+++ b/readconf.h
2322@@ -45,7 +45,12 @@ typedef struct {
2323 int challenge_response_authentication;
2324 /* Try S/Key or TIS, authentication. */
2325 int gss_authentication; /* Try GSS authentication */
2326+ int gss_keyex; /* Try GSS key exchange */
2327 int gss_deleg_creds; /* Delegate GSS credentials */
2328+ int gss_trust_dns; /* Trust DNS for GSS canonicalization */
2329+ int gss_renewal_rekey; /* Credential renewal forces rekey */
2330+ char *gss_client_identity; /* Principal to initiate GSSAPI with */
2331+ char *gss_server_identity; /* GSSAPI target principal */
2332 int password_authentication; /* Try password
2333 * authentication. */
2334 int kbd_interactive_authentication; /* Try keyboard-interactive auth. */
2335diff --git a/servconf.c b/servconf.c
2336index b19d30e..b8af6dd 100644
2337--- a/servconf.c
2338+++ b/servconf.c
2339@@ -117,8 +117,10 @@ initialize_server_options(ServerOptions *options)
2340 options->kerberos_ticket_cleanup = -1;
2341 options->kerberos_get_afs_token = -1;
2342 options->gss_authentication=-1;
2343+ options->gss_keyex = -1;
2344 options->gss_cleanup_creds = -1;
2345 options->gss_strict_acceptor = -1;
2346+ options->gss_store_rekey = -1;
2347 options->password_authentication = -1;
2348 options->kbd_interactive_authentication = -1;
2349 options->challenge_response_authentication = -1;
2350@@ -287,10 +289,14 @@ fill_default_server_options(ServerOptions *options)
2351 options->kerberos_get_afs_token = 0;
2352 if (options->gss_authentication == -1)
2353 options->gss_authentication = 0;
2354+ if (options->gss_keyex == -1)
2355+ options->gss_keyex = 0;
2356 if (options->gss_cleanup_creds == -1)
2357 options->gss_cleanup_creds = 1;
2358 if (options->gss_strict_acceptor == -1)
2359- options->gss_strict_acceptor = 0;
2360+ options->gss_strict_acceptor = 1;
2361+ if (options->gss_store_rekey == -1)
2362+ options->gss_store_rekey = 0;
2363 if (options->password_authentication == -1)
2364 options->password_authentication = 1;
2365 if (options->kbd_interactive_authentication == -1)
2366@@ -419,6 +425,7 @@ typedef enum {
2367 sHostKeyAlgorithms,
2368 sClientAliveInterval, sClientAliveCountMax, sAuthorizedKeysFile,
2369 sGssAuthentication, sGssCleanupCreds, sGssStrictAcceptor,
2370+ sGssKeyEx, sGssStoreRekey,
2371 sAcceptEnv, sPermitTunnel,
2372 sMatch, sPermitOpen, sForceCommand, sChrootDirectory,
2373 sUsePrivilegeSeparation, sAllowAgentForwarding,
2374@@ -492,12 +499,20 @@ static struct {
2375 #ifdef GSSAPI
2376 { "gssapiauthentication", sGssAuthentication, SSHCFG_ALL },
2377 { "gssapicleanupcredentials", sGssCleanupCreds, SSHCFG_GLOBAL },
2378+ { "gssapicleanupcreds", sGssCleanupCreds, SSHCFG_GLOBAL },
2379 { "gssapistrictacceptorcheck", sGssStrictAcceptor, SSHCFG_GLOBAL },
2380+ { "gssapikeyexchange", sGssKeyEx, SSHCFG_GLOBAL },
2381+ { "gssapistorecredentialsonrekey", sGssStoreRekey, SSHCFG_GLOBAL },
2382 #else
2383 { "gssapiauthentication", sUnsupported, SSHCFG_ALL },
2384 { "gssapicleanupcredentials", sUnsupported, SSHCFG_GLOBAL },
2385+ { "gssapicleanupcreds", sUnsupported, SSHCFG_GLOBAL },
2386 { "gssapistrictacceptorcheck", sUnsupported, SSHCFG_GLOBAL },
2387+ { "gssapikeyexchange", sUnsupported, SSHCFG_GLOBAL },
2388+ { "gssapistorecredentialsonrekey", sUnsupported, SSHCFG_GLOBAL },
2389 #endif
2390+ { "gssusesessionccache", sUnsupported, SSHCFG_GLOBAL },
2391+ { "gssapiusesessioncredcache", sUnsupported, SSHCFG_GLOBAL },
2392 { "passwordauthentication", sPasswordAuthentication, SSHCFG_ALL },
2393 { "kbdinteractiveauthentication", sKbdInteractiveAuthentication, SSHCFG_ALL },
2394 { "challengeresponseauthentication", sChallengeResponseAuthentication, SSHCFG_GLOBAL },
2395@@ -1242,6 +1257,10 @@ process_server_config_line(ServerOptions *options, char *line,
2396 intptr = &options->gss_authentication;
2397 goto parse_flag;
2398
2399+ case sGssKeyEx:
2400+ intptr = &options->gss_keyex;
2401+ goto parse_flag;
2402+
2403 case sGssCleanupCreds:
2404 intptr = &options->gss_cleanup_creds;
2405 goto parse_flag;
2406@@ -1250,6 +1269,10 @@ process_server_config_line(ServerOptions *options, char *line,
2407 intptr = &options->gss_strict_acceptor;
2408 goto parse_flag;
2409
2410+ case sGssStoreRekey:
2411+ intptr = &options->gss_store_rekey;
2412+ goto parse_flag;
2413+
2414 case sPasswordAuthentication:
2415 intptr = &options->password_authentication;
2416 goto parse_flag;
2417@@ -2265,7 +2288,10 @@ dump_config(ServerOptions *o)
2418 #endif
2419 #ifdef GSSAPI
2420 dump_cfg_fmtint(sGssAuthentication, o->gss_authentication);
2421+ dump_cfg_fmtint(sGssKeyEx, o->gss_keyex);
2422 dump_cfg_fmtint(sGssCleanupCreds, o->gss_cleanup_creds);
2423+ dump_cfg_fmtint(sGssStrictAcceptor, o->gss_strict_acceptor);
2424+ dump_cfg_fmtint(sGssStoreRekey, o->gss_store_rekey);
2425 #endif
2426 dump_cfg_fmtint(sPasswordAuthentication, o->password_authentication);
2427 dump_cfg_fmtint(sKbdInteractiveAuthentication,
2428diff --git a/servconf.h b/servconf.h
2429index f4137af..778ba17 100644
2430--- a/servconf.h
2431+++ b/servconf.h
2432@@ -118,8 +118,10 @@ typedef struct {
2433 int kerberos_get_afs_token; /* If true, try to get AFS token if
2434 * authenticated with Kerberos. */
2435 int gss_authentication; /* If true, permit GSSAPI authentication */
2436+ int gss_keyex; /* If true, permit GSSAPI key exchange */
2437 int gss_cleanup_creds; /* If true, destroy cred cache on logout */
2438 int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */
2439+ int gss_store_rekey;
2440 int password_authentication; /* If true, permit password
2441 * authentication. */
2442 int kbd_interactive_authentication; /* If true, permit */
2443diff --git a/ssh-gss.h b/ssh-gss.h
2444index a99d7f0..914701b 100644
2445--- a/ssh-gss.h
2446+++ b/ssh-gss.h
2447@@ -1,6 +1,6 @@
2448 /* $OpenBSD: ssh-gss.h,v 1.11 2014/02/26 20:28:44 djm Exp $ */
2449 /*
2450- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
2451+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
2452 *
2453 * Redistribution and use in source and binary forms, with or without
2454 * modification, are permitted provided that the following conditions
2455@@ -61,10 +61,22 @@
2456
2457 #define SSH_GSS_OIDTYPE 0x06
2458
2459+#define SSH2_MSG_KEXGSS_INIT 30
2460+#define SSH2_MSG_KEXGSS_CONTINUE 31
2461+#define SSH2_MSG_KEXGSS_COMPLETE 32
2462+#define SSH2_MSG_KEXGSS_HOSTKEY 33
2463+#define SSH2_MSG_KEXGSS_ERROR 34
2464+#define SSH2_MSG_KEXGSS_GROUPREQ 40
2465+#define SSH2_MSG_KEXGSS_GROUP 41
2466+#define KEX_GSS_GRP1_SHA1_ID "gss-group1-sha1-"
2467+#define KEX_GSS_GRP14_SHA1_ID "gss-group14-sha1-"
2468+#define KEX_GSS_GEX_SHA1_ID "gss-gex-sha1-"
2469+
2470 typedef struct {
2471 char *filename;
2472 char *envvar;
2473 char *envval;
2474+ struct passwd *owner;
2475 void *data;
2476 } ssh_gssapi_ccache;
2477
2478@@ -72,8 +84,11 @@ typedef struct {
2479 gss_buffer_desc displayname;
2480 gss_buffer_desc exportedname;
2481 gss_cred_id_t creds;
2482+ gss_name_t name;
2483 struct ssh_gssapi_mech_struct *mech;
2484 ssh_gssapi_ccache store;
2485+ int used;
2486+ int updated;
2487 } ssh_gssapi_client;
2488
2489 typedef struct ssh_gssapi_mech_struct {
2490@@ -84,6 +99,7 @@ typedef struct ssh_gssapi_mech_struct {
2491 int (*userok) (ssh_gssapi_client *, char *);
2492 int (*localname) (ssh_gssapi_client *, char **);
2493 void (*storecreds) (ssh_gssapi_client *);
2494+ int (*updatecreds) (ssh_gssapi_ccache *, ssh_gssapi_client *);
2495 } ssh_gssapi_mech;
2496
2497 typedef struct {
2498@@ -94,10 +110,11 @@ typedef struct {
2499 gss_OID oid; /* client */
2500 gss_cred_id_t creds; /* server */
2501 gss_name_t client; /* server */
2502- gss_cred_id_t client_creds; /* server */
2503+ gss_cred_id_t client_creds; /* both */
2504 } Gssctxt;
2505
2506 extern ssh_gssapi_mech *supported_mechs[];
2507+extern Gssctxt *gss_kex_context;
2508
2509 int ssh_gssapi_check_oid(Gssctxt *, void *, size_t);
2510 void ssh_gssapi_set_oid_data(Gssctxt *, void *, size_t);
2511@@ -119,16 +136,32 @@ void ssh_gssapi_build_ctx(Gssctxt **);
2512 void ssh_gssapi_delete_ctx(Gssctxt **);
2513 OM_uint32 ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
2514 void ssh_gssapi_buildmic(Buffer *, const char *, const char *, const char *);
2515-int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *);
2516+int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *, const char *);
2517+OM_uint32 ssh_gssapi_client_identity(Gssctxt *, const char *);
2518+int ssh_gssapi_credentials_updated(Gssctxt *);
2519
2520 /* In the server */
2521+typedef int ssh_gssapi_check_fn(Gssctxt **, gss_OID, const char *,
2522+ const char *);
2523+char *ssh_gssapi_client_mechanisms(const char *, const char *);
2524+char *ssh_gssapi_kex_mechs(gss_OID_set, ssh_gssapi_check_fn *, const char *,
2525+ const char *);
2526+gss_OID ssh_gssapi_id_kex(Gssctxt *, char *, int);
2527+int ssh_gssapi_server_check_mech(Gssctxt **,gss_OID, const char *,
2528+ const char *);
2529 OM_uint32 ssh_gssapi_server_ctx(Gssctxt **, gss_OID);
2530-int ssh_gssapi_userok(char *name);
2531+int ssh_gssapi_userok(char *name, struct passwd *);
2532 OM_uint32 ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
2533 void ssh_gssapi_do_child(char ***, u_int *);
2534 void ssh_gssapi_cleanup_creds(void);
2535 void ssh_gssapi_storecreds(void);
2536
2537+char *ssh_gssapi_server_mechanisms(void);
2538+int ssh_gssapi_oid_table_ok(void);
2539+
2540+int ssh_gssapi_update_creds(ssh_gssapi_ccache *store);
2541+void ssh_gssapi_rekey_creds(void);
2542+
2543 #endif /* GSSAPI */
2544
2545 #endif /* _SSH_GSS_H */
2546diff --git a/ssh_config b/ssh_config
2547index 90fb63f..4e879cd 100644
2548--- a/ssh_config
2549+++ b/ssh_config
2550@@ -26,6 +26,8 @@
2551 # HostbasedAuthentication no
2552 # GSSAPIAuthentication no
2553 # GSSAPIDelegateCredentials no
2554+# GSSAPIKeyExchange no
2555+# GSSAPITrustDNS no
2556 # BatchMode no
2557 # CheckHostIP yes
2558 # AddressFamily any
2559diff --git a/ssh_config.5 b/ssh_config.5
2560index caf13a6..9060d5b 100644
2561--- a/ssh_config.5
2562+++ b/ssh_config.5
2563@@ -826,10 +826,42 @@ The default is
2564 Specifies whether user authentication based on GSSAPI is allowed.
2565 The default is
2566 .Dq no .
2567+.It Cm GSSAPIKeyExchange
2568+Specifies whether key exchange based on GSSAPI may be used. When using
2569+GSSAPI key exchange the server need not have a host key.
2570+The default is
2571+.Dq no .
2572+.It Cm GSSAPIClientIdentity
2573+If set, specifies the GSSAPI client identity that ssh should use when
2574+connecting to the server. The default is unset, which means that the default
2575+identity will be used.
2576+.It Cm GSSAPIServerIdentity
2577+If set, specifies the GSSAPI server identity that ssh should expect when
2578+connecting to the server. The default is unset, which means that the
2579+expected GSSAPI server identity will be determined from the target
2580+hostname.
2581 .It Cm GSSAPIDelegateCredentials
2582 Forward (delegate) credentials to the server.
2583 The default is
2584 .Dq no .
2585+.It Cm GSSAPIRenewalForcesRekey
2586+If set to
2587+.Dq yes
2588+then renewal of the client's GSSAPI credentials will force the rekeying of the
2589+ssh connection. With a compatible server, this can delegate the renewed
2590+credentials to a session on the server.
2591+The default is
2592+.Dq no .
2593+.It Cm GSSAPITrustDns
2594+Set to
2595+.Dq yes
2596+to indicate that the DNS is trusted to securely canonicalize
2597+the name of the host being connected to. If
2598+.Dq no ,
2599+the hostname entered on the
2600+command line will be passed untouched to the GSSAPI library.
2601+The default is
2602+.Dq no .
2603 .It Cm HashKnownHosts
2604 Indicates that
2605 .Xr ssh 1
2606diff --git a/sshconnect2.c b/sshconnect2.c
2607index f79c96b..b452eae 100644
2608--- a/sshconnect2.c
2609+++ b/sshconnect2.c
2610@@ -161,6 +161,11 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
2611 struct kex *kex;
2612 int r;
2613
2614+#ifdef GSSAPI
2615+ char *orig = NULL, *gss = NULL;
2616+ char *gss_host = NULL;
2617+#endif
2618+
2619 xxx_host = host;
2620 xxx_hostaddr = hostaddr;
2621
2622@@ -195,6 +200,33 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
2623 order_hostkeyalgs(host, hostaddr, port));
2624 }
2625
2626+#ifdef GSSAPI
2627+ if (options.gss_keyex) {
2628+ /* Add the GSSAPI mechanisms currently supported on this
2629+ * client to the key exchange algorithm proposal */
2630+ orig = myproposal[PROPOSAL_KEX_ALGS];
2631+
2632+ if (options.gss_trust_dns)
2633+ gss_host = (char *)get_canonical_hostname(1);
2634+ else
2635+ gss_host = host;
2636+
2637+ gss = ssh_gssapi_client_mechanisms(gss_host, options.gss_client_identity);
2638+ if (gss) {
2639+ debug("Offering GSSAPI proposal: %s", gss);
2640+ xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
2641+ "%s,%s", gss, orig);
2642+
2643+ /* If we've got GSSAPI algorithms, then we also
2644+ * support the 'null' hostkey, as a last resort */
2645+ orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
2646+ xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],
2647+ "%s,null", orig);
2648+ free(gss);
2649+ }
2650+ }
2651+#endif
2652+
2653 if (options.rekey_limit || options.rekey_interval)
2654 packet_set_rekey_limits((u_int32_t)options.rekey_limit,
2655 (time_t)options.rekey_interval);
2656@@ -213,10 +245,30 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
2657 # endif
2658 #endif
2659 kex->kex[KEX_C25519_SHA256] = kexc25519_client;
2660+#ifdef GSSAPI
2661+ if (options.gss_keyex) {
2662+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_client;
2663+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_client;
2664+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_client;
2665+ }
2666+#endif
2667 kex->client_version_string=client_version_string;
2668 kex->server_version_string=server_version_string;
2669 kex->verify_host_key=&verify_host_key_callback;
2670
2671+#ifdef GSSAPI
2672+ if (options.gss_keyex) {
2673+ kex->gss_deleg_creds = options.gss_deleg_creds;
2674+ kex->gss_trust_dns = options.gss_trust_dns;
2675+ kex->gss_client = options.gss_client_identity;
2676+ if (options.gss_server_identity) {
2677+ kex->gss_host = options.gss_server_identity;
2678+ } else {
2679+ kex->gss_host = gss_host;
2680+ }
2681+ }
2682+#endif
2683+
2684 dispatch_run(DISPATCH_BLOCK, &kex->done, active_state);
2685
2686 /* remove ext-info from the KEX proposals for rekeying */
2687@@ -311,6 +363,7 @@ int input_gssapi_token(int type, u_int32_t, void *);
2688 int input_gssapi_hash(int type, u_int32_t, void *);
2689 int input_gssapi_error(int, u_int32_t, void *);
2690 int input_gssapi_errtok(int, u_int32_t, void *);
2691+int userauth_gsskeyex(Authctxt *authctxt);
2692 #endif
2693
2694 void userauth(Authctxt *, char *);
2695@@ -326,6 +379,11 @@ static char *authmethods_get(void);
2696
2697 Authmethod authmethods[] = {
2698 #ifdef GSSAPI
2699+ {"gssapi-keyex",
2700+ userauth_gsskeyex,
2701+ NULL,
2702+ &options.gss_authentication,
2703+ NULL},
2704 {"gssapi-with-mic",
2705 userauth_gssapi,
2706 NULL,
2707@@ -656,19 +714,31 @@ userauth_gssapi(Authctxt *authctxt)
2708 static u_int mech = 0;
2709 OM_uint32 min;
2710 int ok = 0;
2711+ const char *gss_host;
2712+
2713+ if (options.gss_server_identity)
2714+ gss_host = options.gss_server_identity;
2715+ else if (options.gss_trust_dns)
2716+ gss_host = get_canonical_hostname(1);
2717+ else
2718+ gss_host = authctxt->host;
2719
2720 /* Try one GSSAPI method at a time, rather than sending them all at
2721 * once. */
2722
2723 if (gss_supported == NULL)
2724- gss_indicate_mechs(&min, &gss_supported);
2725+ if (GSS_ERROR(gss_indicate_mechs(&min, &gss_supported))) {
2726+ gss_supported = NULL;
2727+ return 0;
2728+ }
2729
2730 /* Check to see if the mechanism is usable before we offer it */
2731 while (mech < gss_supported->count && !ok) {
2732 /* My DER encoding requires length<128 */
2733 if (gss_supported->elements[mech].length < 128 &&
2734 ssh_gssapi_check_mechanism(&gssctxt,
2735- &gss_supported->elements[mech], authctxt->host)) {
2736+ &gss_supported->elements[mech], gss_host,
2737+ options.gss_client_identity)) {
2738 ok = 1; /* Mechanism works */
2739 } else {
2740 mech++;
2741@@ -765,8 +835,8 @@ input_gssapi_response(int type, u_int32_t plen, void *ctxt)
2742 {
2743 Authctxt *authctxt = ctxt;
2744 Gssctxt *gssctxt;
2745- int oidlen;
2746- char *oidv;
2747+ u_int oidlen;
2748+ u_char *oidv;
2749
2750 if (authctxt == NULL)
2751 fatal("input_gssapi_response: no authentication context");
2752@@ -879,6 +949,48 @@ input_gssapi_error(int type, u_int32_t plen, void *ctxt)
2753 free(lang);
2754 return 0;
2755 }
2756+
2757+int
2758+userauth_gsskeyex(Authctxt *authctxt)
2759+{
2760+ Buffer b;
2761+ gss_buffer_desc gssbuf;
2762+ gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
2763+ OM_uint32 ms;
2764+
2765+ static int attempt = 0;
2766+ if (attempt++ >= 1)
2767+ return (0);
2768+
2769+ if (gss_kex_context == NULL) {
2770+ debug("No valid Key exchange context");
2771+ return (0);
2772+ }
2773+
2774+ ssh_gssapi_buildmic(&b, authctxt->server_user, authctxt->service,
2775+ "gssapi-keyex");
2776+
2777+ gssbuf.value = buffer_ptr(&b);
2778+ gssbuf.length = buffer_len(&b);
2779+
2780+ if (GSS_ERROR(ssh_gssapi_sign(gss_kex_context, &gssbuf, &mic))) {
2781+ buffer_free(&b);
2782+ return (0);
2783+ }
2784+
2785+ packet_start(SSH2_MSG_USERAUTH_REQUEST);
2786+ packet_put_cstring(authctxt->server_user);
2787+ packet_put_cstring(authctxt->service);
2788+ packet_put_cstring(authctxt->method->name);
2789+ packet_put_string(mic.value, mic.length);
2790+ packet_send();
2791+
2792+ buffer_free(&b);
2793+ gss_release_buffer(&ms, &mic);
2794+
2795+ return (1);
2796+}
2797+
2798 #endif /* GSSAPI */
2799
2800 int
2801diff --git a/sshd.c b/sshd.c
2802index 430569c..5cd9129 100644
2803--- a/sshd.c
2804+++ b/sshd.c
2805@@ -125,6 +125,10 @@
2806 #include "version.h"
2807 #include "ssherr.h"
2808
2809+#ifdef USE_SECURITY_SESSION_API
2810+#include <Security/AuthSession.h>
2811+#endif
2812+
2813 #ifndef O_NOCTTY
2814 #define O_NOCTTY 0
2815 #endif
2816@@ -1833,10 +1837,13 @@ main(int ac, char **av)
2817 logit("Disabling protocol version 1. Could not load host key");
2818 options.protocol &= ~SSH_PROTO_1;
2819 }
2820+#ifndef GSSAPI
2821+ /* The GSSAPI key exchange can run without a host key */
2822 if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) {
2823 logit("Disabling protocol version 2. Could not load host key");
2824 options.protocol &= ~SSH_PROTO_2;
2825 }
2826+#endif
2827 if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) {
2828 logit("sshd: no hostkeys available -- exiting.");
2829 exit(1);
2830@@ -2151,6 +2158,60 @@ main(int ac, char **av)
2831 remote_ip, remote_port, laddr, get_local_port());
2832 free(laddr);
2833
2834+#ifdef USE_SECURITY_SESSION_API
2835+ /*
2836+ * Create a new security session for use by the new user login if
2837+ * the current session is the root session or we are not launched
2838+ * by inetd (eg: debugging mode or server mode). We do not
2839+ * necessarily need to create a session if we are launched from
2840+ * inetd because Panther xinetd will create a session for us.
2841+ *
2842+ * The only case where this logic will fail is if there is an
2843+ * inetd running in a non-root session which is not creating
2844+ * new sessions for us. Then all the users will end up in the
2845+ * same session (bad).
2846+ *
2847+ * When the client exits, the session will be destroyed for us
2848+ * automatically.
2849+ *
2850+ * We must create the session before any credentials are stored
2851+ * (including AFS pags, which happens a few lines below).
2852+ */
2853+ {
2854+ OSStatus err = 0;
2855+ SecuritySessionId sid = 0;
2856+ SessionAttributeBits sattrs = 0;
2857+
2858+ err = SessionGetInfo(callerSecuritySession, &sid, &sattrs);
2859+ if (err)
2860+ error("SessionGetInfo() failed with error %.8X",
2861+ (unsigned) err);
2862+ else
2863+ debug("Current Session ID is %.8X / Session Attributes are %.8X",
2864+ (unsigned) sid, (unsigned) sattrs);
2865+
2866+ if (inetd_flag && !(sattrs & sessionIsRoot))
2867+ debug("Running in inetd mode in a non-root session... "
2868+ "assuming inetd created the session for us.");
2869+ else {
2870+ debug("Creating new security session...");
2871+ err = SessionCreate(0, sessionHasTTY | sessionIsRemote);
2872+ if (err)
2873+ error("SessionCreate() failed with error %.8X",
2874+ (unsigned) err);
2875+
2876+ err = SessionGetInfo(callerSecuritySession, &sid,
2877+ &sattrs);
2878+ if (err)
2879+ error("SessionGetInfo() failed with error %.8X",
2880+ (unsigned) err);
2881+ else
2882+ debug("New Session ID is %.8X / Session Attributes are %.8X",
2883+ (unsigned) sid, (unsigned) sattrs);
2884+ }
2885+ }
2886+#endif
2887+
2888 /*
2889 * We don't want to listen forever unless the other side
2890 * successfully authenticates itself. So we set up an alarm which is
2891@@ -2571,6 +2632,48 @@ do_ssh2_kex(void)
2892 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = compat_pkalg_proposal(
2893 list_hostkey_types());
2894
2895+#ifdef GSSAPI
2896+ {
2897+ char *orig;
2898+ char *gss = NULL;
2899+ char *newstr = NULL;
2900+ orig = myproposal[PROPOSAL_KEX_ALGS];
2901+
2902+ /*
2903+ * If we don't have a host key, then there's no point advertising
2904+ * the other key exchange algorithms
2905+ */
2906+
2907+ if (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]) == 0)
2908+ orig = NULL;
2909+
2910+ if (options.gss_keyex)
2911+ gss = ssh_gssapi_server_mechanisms();
2912+ else
2913+ gss = NULL;
2914+
2915+ if (gss && orig)
2916+ xasprintf(&newstr, "%s,%s", gss, orig);
2917+ else if (gss)
2918+ newstr = gss;
2919+ else if (orig)
2920+ newstr = orig;
2921+
2922+ /*
2923+ * If we've got GSSAPI mechanisms, then we've got the 'null' host
2924+ * key alg, but we can't tell people about it unless its the only
2925+ * host key algorithm we support
2926+ */
2927+ if (gss && (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS])) == 0)
2928+ myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = "null";
2929+
2930+ if (newstr)
2931+ myproposal[PROPOSAL_KEX_ALGS] = newstr;
2932+ else
2933+ fatal("No supported key exchange algorithms");
2934+ }
2935+#endif
2936+
2937 /* start key exchange */
2938 if ((r = kex_setup(active_state, myproposal)) != 0)
2939 fatal("kex_setup: %s", ssh_err(r));
2940@@ -2585,6 +2688,13 @@ do_ssh2_kex(void)
2941 # endif
2942 #endif
2943 kex->kex[KEX_C25519_SHA256] = kexc25519_server;
2944+#ifdef GSSAPI
2945+ if (options.gss_keyex) {
2946+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
2947+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
2948+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_server;
2949+ }
2950+#endif
2951 kex->server = 1;
2952 kex->client_version_string=client_version_string;
2953 kex->server_version_string=server_version_string;
2954diff --git a/sshd_config b/sshd_config
2955index a848d73..f103298 100644
2956--- a/sshd_config
2957+++ b/sshd_config
2958@@ -84,6 +84,8 @@ AuthorizedKeysFile .ssh/authorized_keys
2959 # GSSAPI options
2960 #GSSAPIAuthentication no
2961 #GSSAPICleanupCredentials yes
2962+#GSSAPIStrictAcceptorCheck yes
2963+#GSSAPIKeyExchange no
2964
2965 # Set this to 'yes' to enable PAM authentication, account processing,
2966 # and session processing. If this is enabled, PAM authentication will
2967diff --git a/sshd_config.5 b/sshd_config.5
2968index a37a3ac..c6d6858 100644
2969--- a/sshd_config.5
2970+++ b/sshd_config.5
2971@@ -623,6 +623,11 @@ The default is
2972 Specifies whether user authentication based on GSSAPI is allowed.
2973 The default is
2974 .Dq no .
2975+.It Cm GSSAPIKeyExchange
2976+Specifies whether key exchange based on GSSAPI is allowed. GSSAPI key exchange
2977+doesn't rely on ssh keys to verify host identity.
2978+The default is
2979+.Dq no .
2980 .It Cm GSSAPICleanupCredentials
2981 Specifies whether to automatically destroy the user's credentials cache
2982 on logout.
2983@@ -643,6 +648,11 @@ machine's default store.
2984 This facility is provided to assist with operation on multi homed machines.
2985 The default is
2986 .Dq yes .
2987+.It Cm GSSAPIStoreCredentialsOnRekey
2988+Controls whether the user's GSSAPI credentials should be updated following a
2989+successful connection rekeying. This option can be used to accepted renewed
2990+or updated credentials from a compatible client. The default is
2991+.Dq no .
2992 .It Cm HostbasedAcceptedKeyTypes
2993 Specifies the key types that will be accepted for hostbased authentication
2994 as a comma-separated pattern list.
2995diff --git a/sshkey.c b/sshkey.c
2996index 87b093e..e595b11 100644
2997--- a/sshkey.c
2998+++ b/sshkey.c
2999@@ -115,6 +115,7 @@ static const struct keytype keytypes[] = {
3000 # endif /* OPENSSL_HAS_NISTP521 */
3001 # endif /* OPENSSL_HAS_ECC */
3002 #endif /* WITH_OPENSSL */
3003+ { "null", "null", KEY_NULL, 0, 0, 0 },
3004 { NULL, NULL, -1, -1, 0, 0 }
3005 };
3006
3007@@ -203,7 +204,7 @@ key_alg_list(int certs_only, int plain_only)
3008 const struct keytype *kt;
3009
3010 for (kt = keytypes; kt->type != -1; kt++) {
3011- if (kt->name == NULL || kt->sigonly)
3012+ if (kt->name == NULL || kt->sigonly || kt->type == KEY_NULL)
3013 continue;
3014 if ((certs_only && !kt->cert) || (plain_only && kt->cert))
3015 continue;
3016diff --git a/sshkey.h b/sshkey.h
3017index a20a14f..2259cbb 100644
3018--- a/sshkey.h
3019+++ b/sshkey.h
3020@@ -62,6 +62,7 @@ enum sshkey_types {
3021 KEY_DSA_CERT,
3022 KEY_ECDSA_CERT,
3023 KEY_ED25519_CERT,
3024+ KEY_NULL,
3025 KEY_UNSPEC
3026 };
3027
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-08 05:02:13 +0000