Initial commit of GSSAPI Kerberos support.
[u/mdw/putty] / unix / uxgss.c
1 #ifndef NO_GSSAPI
2
3 #include <string.h>
4 #include <gssapi/gssapi_krb5.h>
5 #include "sshgss.h"
6 #include "misc.h"
7
8 typedef struct uxSsh_gss_ctx {
9 OM_uint32 maj_stat;
10 OM_uint32 min_stat;
11 gss_ctx_id_t ctx;
12 } uxSsh_gss_ctx;
13
14 int ssh_gss_init(void)
15 {
16 /* On Windows this tries to load the SSPI library functions. On
17 Unix we assume we have GSSAPI at runtime if we were linked with
18 it at compile time */
19 return 1;
20 }
21
22 Ssh_gss_stat ssh_gss_indicate_mech(Ssh_gss_buf *mech)
23 {
24 /* Copy constant into mech */
25 mech->len = gss_mech_krb5->length;
26 mech->data = gss_mech_krb5->elements;
27
28 return SSH_GSS_OK;
29 }
30
31 Ssh_gss_stat ssh_gss_import_name(char *host,
32 Ssh_gss_name *srv_name)
33 {
34 OM_uint32 min_stat,maj_stat;
35 gss_buffer_desc host_buf;
36 char *pStr;
37
38 pStr = dupcat("host@", host, NULL);
39
40 host_buf.value = pStr;
41 host_buf.length = strlen(pStr);
42
43 maj_stat = gss_import_name(&min_stat, &host_buf,
44 GSS_C_NT_HOSTBASED_SERVICE,
45 (gss_name_t *)srv_name);
46 /* Release buffer */
47 sfree(pStr);
48 if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
49 return SSH_GSS_FAILURE;
50 }
51
52 Ssh_gss_stat ssh_gss_acquire_cred(Ssh_gss_ctx *ctx)
53 {
54 uxSsh_gss_ctx *uxctx = snew(uxSsh_gss_ctx);
55
56 uxctx->maj_stat = uxctx->min_stat = GSS_S_COMPLETE;
57 uxctx->ctx = GSS_C_NO_CONTEXT;
58 *ctx = (Ssh_gss_ctx) uxctx;
59
60 return SSH_GSS_OK;
61 }
62
63 Ssh_gss_stat ssh_gss_init_sec_context(Ssh_gss_ctx *ctx,
64 Ssh_gss_name srv_name,
65 int to_deleg,
66 Ssh_gss_buf *recv_tok,
67 Ssh_gss_buf *send_tok)
68 {
69 uxSsh_gss_ctx *uxctx = (uxSsh_gss_ctx*) *ctx;
70 OM_uint32 ret_flags;
71
72 if (to_deleg) to_deleg = GSS_C_DELEG_FLAG;
73 uxctx->maj_stat = gss_init_sec_context(&uxctx->min_stat,
74 GSS_C_NO_CREDENTIAL,
75 &uxctx->ctx,
76 (gss_name_t) srv_name,
77 (gss_OID) gss_mech_krb5,
78 GSS_C_MUTUAL_FLAG |
79 GSS_C_INTEG_FLAG | to_deleg,
80 0,
81 NULL, /* no channel bindings */
82 (gss_buffer_desc *)recv_tok,
83 NULL, /* ignore mech type */
84 (gss_buffer_desc *)send_tok,
85 &ret_flags,
86 NULL); /* ignore time_rec */
87
88 if (uxctx->maj_stat == GSS_S_COMPLETE) return SSH_GSS_S_COMPLETE;
89 if (uxctx->maj_stat == GSS_S_CONTINUE_NEEDED) return SSH_GSS_S_CONTINUE_NEEDED;
90 return SSH_GSS_FAILURE;
91 }
92
93 Ssh_gss_stat ssh_gss_display_status(Ssh_gss_ctx ctx, Ssh_gss_buf *buf)
94 {
95 uxSsh_gss_ctx *uxctx = (uxSsh_gss_ctx *) ctx;
96 OM_uint32 lmin,lmax;
97 OM_uint32 ccc;
98 gss_buffer_desc msg_maj=GSS_C_EMPTY_BUFFER;
99 gss_buffer_desc msg_min=GSS_C_EMPTY_BUFFER;
100
101 /* Return empty buffer in case of failure */
102 SSH_GSS_CLEAR_BUF(buf);
103
104 /* get first mesg from GSS */
105 ccc=0;
106 lmax=gss_display_status(&lmin,uxctx->maj_stat,GSS_C_GSS_CODE,(gss_OID) gss_mech_krb5,&ccc,&msg_maj);
107
108 if (lmax != GSS_S_COMPLETE) return SSH_GSS_FAILURE;
109
110 /* get first mesg from Kerberos */
111 ccc=0;
112 lmax=gss_display_status(&lmin,uxctx->min_stat,GSS_C_MECH_CODE,(gss_OID) gss_mech_krb5,&ccc,&msg_min);
113
114 if (lmax != GSS_S_COMPLETE) {
115 gss_release_buffer(&lmin, &msg_maj);
116 return SSH_GSS_FAILURE;
117 }
118
119 /* copy data into buffer */
120 buf->len = msg_maj.length + msg_min.length + 1;
121 buf->data = snewn(buf->len + 1, char);
122
123 /* copy mem */
124 memcpy(buf->data, msg_maj.value, msg_maj.length);
125 buf->data[msg_maj.length] = ' ';
126 memcpy(buf->data + msg_maj.length + 1, msg_min.value, msg_min.length);
127 buf->data[buf->len] = 0;
128 /* free mem & exit */
129 gss_release_buffer(&lmin, &msg_maj);
130 gss_release_buffer(&lmin, &msg_min);
131 return SSH_GSS_OK;
132 }
133
134 Ssh_gss_stat ssh_gss_free_tok(Ssh_gss_buf *send_tok)
135 {
136 OM_uint32 min_stat,maj_stat;
137 maj_stat = gss_release_buffer(&min_stat, (gss_buffer_desc *)send_tok);
138
139 if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
140 return SSH_GSS_FAILURE;
141 }
142
143 Ssh_gss_stat ssh_gss_release_cred(Ssh_gss_ctx *ctx)
144 {
145 uxSsh_gss_ctx *uxctx = (uxSsh_gss_ctx *) *ctx;
146 OM_uint32 min_stat;
147 OM_uint32 maj_stat=GSS_S_COMPLETE;
148
149 if (uxctx == NULL) return SSH_GSS_FAILURE;
150 if (uxctx->ctx != GSS_C_NO_CONTEXT)
151 maj_stat = gss_delete_sec_context(&min_stat,&uxctx->ctx,GSS_C_NO_BUFFER);
152 sfree(uxctx);
153
154 if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
155 return SSH_GSS_FAILURE;
156 }
157
158
159 Ssh_gss_stat ssh_gss_release_name(Ssh_gss_name *srv_name)
160 {
161 OM_uint32 min_stat,maj_stat;
162 maj_stat = gss_release_name(&min_stat, (gss_name_t) srv_name);
163
164 if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
165 return SSH_GSS_FAILURE;
166 }
167
168 Ssh_gss_stat ssh_gss_get_mic(Ssh_gss_ctx ctx, Ssh_gss_buf *buf,
169 Ssh_gss_buf *hash)
170 {
171 uxSsh_gss_ctx *uxctx = (uxSsh_gss_ctx *) ctx;
172 if (uxctx == NULL) return SSH_GSS_FAILURE;
173 return gss_get_mic(&(uxctx->min_stat),
174 uxctx->ctx,
175 0,
176 (gss_buffer_desc *)buf,
177 (gss_buffer_desc *)hash);
178 }
179
180 Ssh_gss_stat ssh_gss_free_mic(Ssh_gss_buf *hash)
181 {
182 /* On Unix this is the same freeing process as ssh_gss_free_tok. */
183 return ssh_gss_free_tok(hash);
184 }
185
186 #else
187
188 /* Dummy function so this source file defines something if NO_GSSAPI
189 is defined. */
190
191 int ssh_gss_init(void)
192 {
193 return 1;
194 }
195
196 #endif