diff options
author | Colin Watson <cjwatson@debian.org> | 2003-09-23 18:08:35 +0000 |
---|---|---|
committer | Colin Watson <cjwatson@debian.org> | 2003-09-23 18:08:35 +0000 |
commit | d59fd3e421aa81b8e5e118f3f806081df2aca879 (patch) | |
tree | 356a4e607edc979c625bb33db63c656d771478bd /auth2-gss.c | |
parent | 7505658c58e96b8d270f1928a0e1fa7f3e0c266b (diff) | |
parent | 45431c9b4677608680cd071768cbf156b316a7e8 (diff) |
Merge 3.7.1p2 to the trunk. I have absolutely no idea yet whether this will
work.
Diffstat (limited to 'auth2-gss.c')
-rw-r--r-- | auth2-gss.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/auth2-gss.c b/auth2-gss.c new file mode 100644 index 000000000..75b94b009 --- /dev/null +++ b/auth2-gss.c | |||
@@ -0,0 +1,247 @@ | |||
1 | /* $OpenBSD: auth2-gss.c,v 1.3 2003/09/01 20:44:54 markus Exp $ */ | ||
2 | |||
3 | /* | ||
4 | * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved. | ||
5 | * | ||
6 | * Redistribution and use in source and binary forms, with or without | ||
7 | * modification, are permitted provided that the following conditions | ||
8 | * are met: | ||
9 | * 1. Redistributions of source code must retain the above copyright | ||
10 | * notice, this list of conditions and the following disclaimer. | ||
11 | * 2. Redistributions in binary form must reproduce the above copyright | ||
12 | * notice, this list of conditions and the following disclaimer in the | ||
13 | * documentation and/or other materials provided with the distribution. | ||
14 | * | ||
15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AS IS'' AND ANY EXPRESS OR | ||
16 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | ||
17 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | ||
18 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | ||
19 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | ||
20 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | ||
21 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | ||
22 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | ||
24 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
25 | */ | ||
26 | |||
27 | #include "includes.h" | ||
28 | |||
29 | #ifdef GSSAPI | ||
30 | |||
31 | #include "auth.h" | ||
32 | #include "ssh2.h" | ||
33 | #include "xmalloc.h" | ||
34 | #include "log.h" | ||
35 | #include "dispatch.h" | ||
36 | #include "servconf.h" | ||
37 | #include "compat.h" | ||
38 | #include "packet.h" | ||
39 | #include "monitor_wrap.h" | ||
40 | |||
41 | #include "ssh-gss.h" | ||
42 | |||
43 | extern ServerOptions options; | ||
44 | |||
45 | static void input_gssapi_token(int type, u_int32_t plen, void *ctxt); | ||
46 | static void input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt); | ||
47 | static void input_gssapi_errtok(int, u_int32_t, void *); | ||
48 | |||
49 | /* | ||
50 | * We only support those mechanisms that we know about (ie ones that we know | ||
51 | * how to check local user kuserok and the like | ||
52 | */ | ||
53 | static int | ||
54 | userauth_gssapi(Authctxt *authctxt) | ||
55 | { | ||
56 | gss_OID_desc oid = {0, NULL}; | ||
57 | Gssctxt *ctxt = NULL; | ||
58 | int mechs; | ||
59 | gss_OID_set supported; | ||
60 | int present; | ||
61 | OM_uint32 ms; | ||
62 | u_int len; | ||
63 | char *doid = NULL; | ||
64 | |||
65 | if (!authctxt->valid || authctxt->user == NULL) | ||
66 | return (0); | ||
67 | |||
68 | mechs = packet_get_int(); | ||
69 | if (mechs == 0) { | ||
70 | debug("Mechanism negotiation is not supported"); | ||
71 | return (0); | ||
72 | } | ||
73 | |||
74 | ssh_gssapi_supported_oids(&supported); | ||
75 | do { | ||
76 | mechs--; | ||
77 | |||
78 | if (doid) | ||
79 | xfree(doid); | ||
80 | |||
81 | doid = packet_get_string(&len); | ||
82 | |||
83 | if (doid[0] != SSH_GSS_OIDTYPE || doid[1] != len-2) { | ||
84 | logit("Mechanism OID received using the old encoding form"); | ||
85 | oid.elements = doid; | ||
86 | oid.length = len; | ||
87 | } else { | ||
88 | oid.elements = doid + 2; | ||
89 | oid.length = len - 2; | ||
90 | } | ||
91 | gss_test_oid_set_member(&ms, &oid, supported, &present); | ||
92 | } while (mechs > 0 && !present); | ||
93 | |||
94 | gss_release_oid_set(&ms, &supported); | ||
95 | |||
96 | if (!present) { | ||
97 | xfree(doid); | ||
98 | return (0); | ||
99 | } | ||
100 | |||
101 | if (GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctxt, &oid)))) { | ||
102 | xfree(doid); | ||
103 | return (0); | ||
104 | } | ||
105 | |||
106 | authctxt->methoddata=(void *)ctxt; | ||
107 | |||
108 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE); | ||
109 | |||
110 | /* Return OID in same format as we received it*/ | ||
111 | packet_put_string(doid, len); | ||
112 | |||
113 | packet_send(); | ||
114 | xfree(doid); | ||
115 | |||
116 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token); | ||
117 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok); | ||
118 | authctxt->postponed = 1; | ||
119 | |||
120 | return (0); | ||
121 | } | ||
122 | |||
123 | static void | ||
124 | input_gssapi_token(int type, u_int32_t plen, void *ctxt) | ||
125 | { | ||
126 | Authctxt *authctxt = ctxt; | ||
127 | Gssctxt *gssctxt; | ||
128 | gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER; | ||
129 | gss_buffer_desc recv_tok; | ||
130 | OM_uint32 maj_status, min_status; | ||
131 | u_int len; | ||
132 | |||
133 | if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep)) | ||
134 | fatal("No authentication or GSSAPI context"); | ||
135 | |||
136 | gssctxt = authctxt->methoddata; | ||
137 | recv_tok.value = packet_get_string(&len); | ||
138 | recv_tok.length = len; /* u_int vs. size_t */ | ||
139 | |||
140 | packet_check_eom(); | ||
141 | |||
142 | maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok, | ||
143 | &send_tok, NULL)); | ||
144 | |||
145 | xfree(recv_tok.value); | ||
146 | |||
147 | if (GSS_ERROR(maj_status)) { | ||
148 | if (send_tok.length != 0) { | ||
149 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK); | ||
150 | packet_put_string(send_tok.value, send_tok.length); | ||
151 | packet_send(); | ||
152 | } | ||
153 | authctxt->postponed = 0; | ||
154 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); | ||
155 | userauth_finish(authctxt, 0, "gssapi"); | ||
156 | } else { | ||
157 | if (send_tok.length != 0) { | ||
158 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN); | ||
159 | packet_put_string(send_tok.value, send_tok.length); | ||
160 | packet_send(); | ||
161 | } | ||
162 | if (maj_status == GSS_S_COMPLETE) { | ||
163 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); | ||
164 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, | ||
165 | &input_gssapi_exchange_complete); | ||
166 | } | ||
167 | } | ||
168 | |||
169 | gss_release_buffer(&min_status, &send_tok); | ||
170 | } | ||
171 | |||
172 | static void | ||
173 | input_gssapi_errtok(int type, u_int32_t plen, void *ctxt) | ||
174 | { | ||
175 | Authctxt *authctxt = ctxt; | ||
176 | Gssctxt *gssctxt; | ||
177 | gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER; | ||
178 | gss_buffer_desc recv_tok; | ||
179 | OM_uint32 maj_status; | ||
180 | u_int len; | ||
181 | |||
182 | if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep)) | ||
183 | fatal("No authentication or GSSAPI context"); | ||
184 | |||
185 | gssctxt = authctxt->methoddata; | ||
186 | recv_tok.value = packet_get_string(&len); | ||
187 | recv_tok.length = len; | ||
188 | |||
189 | packet_check_eom(); | ||
190 | |||
191 | /* Push the error token into GSSAPI to see what it says */ | ||
192 | maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok, | ||
193 | &send_tok, NULL)); | ||
194 | |||
195 | xfree(recv_tok.value); | ||
196 | |||
197 | /* We can't return anything to the client, even if we wanted to */ | ||
198 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); | ||
199 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, NULL); | ||
200 | |||
201 | /* The client will have already moved on to the next auth */ | ||
202 | |||
203 | gss_release_buffer(&maj_status, &send_tok); | ||
204 | } | ||
205 | |||
206 | /* | ||
207 | * This is called when the client thinks we've completed authentication. | ||
208 | * It should only be enabled in the dispatch handler by the function above, | ||
209 | * which only enables it once the GSSAPI exchange is complete. | ||
210 | */ | ||
211 | |||
212 | static void | ||
213 | input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt) | ||
214 | { | ||
215 | Authctxt *authctxt = ctxt; | ||
216 | Gssctxt *gssctxt; | ||
217 | int authenticated; | ||
218 | |||
219 | if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep)) | ||
220 | fatal("No authentication or GSSAPI context"); | ||
221 | |||
222 | gssctxt = authctxt->methoddata; | ||
223 | |||
224 | /* | ||
225 | * We don't need to check the status, because the stored credentials | ||
226 | * which userok uses are only populated once the context init step | ||
227 | * has returned complete. | ||
228 | */ | ||
229 | |||
230 | packet_check_eom(); | ||
231 | |||
232 | authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user)); | ||
233 | |||
234 | authctxt->postponed = 0; | ||
235 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); | ||
236 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, NULL); | ||
237 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL); | ||
238 | userauth_finish(authctxt, authenticated, "gssapi"); | ||
239 | } | ||
240 | |||
241 | Authmethod method_gssapi = { | ||
242 | "gssapi", | ||
243 | userauth_gssapi, | ||
244 | &options.gss_authentication | ||
245 | }; | ||
246 | |||
247 | #endif /* GSSAPI */ | ||