1 /*
2  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 
7 /*
8  * lib/krb5/keytab/ktbase.c
9  *
10  * Copyright 1990 by the Massachusetts Institute of Technology.
11  * All Rights Reserved.
12  *
13  * Export of this software from the United States of America may
14  *   require a specific license from the United States Government.
15  *   It is the responsibility of any person or organization contemplating
16  *   export to obtain such a license before exporting.
17  *
18  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
19  * distribute this software and its documentation for any purpose and
20  * without fee is hereby granted, provided that the above copyright
21  * notice appear in all copies and that both that copyright notice and
22  * this permission notice appear in supporting documentation, and that
23  * the name of M.I.T. not be used in advertising or publicity pertaining
24  * to distribution of the software without specific, written prior
25  * permission.  Furthermore if you modify this software you must label
26  * your software as modified software and not distribute it in such a
27  * fashion that it might be confused with the original M.I.T. software.
28  * M.I.T. makes no representations about the suitability of
29  * this software for any purpose.  It is provided "as is" without express
30  * or implied warranty.
31  *
32  *
33  * Registration functions for keytab.
34  */
35 
36 #include "k5-int.h"
37 #include "k5-thread.h"
38 #include "kt-int.h"
39 
40 extern const krb5_kt_ops krb5_ktf_ops;
41 extern const krb5_kt_ops krb5_ktf_writable_ops;
42 extern const krb5_kt_ops krb5_kts_ops;
43 
44 struct krb5_kt_typelist {
45     const krb5_kt_ops *ops;
46     const struct krb5_kt_typelist *next;
47 };
48 /* Solaris Kerberos */
49 static const struct krb5_kt_typelist krb5_kt_typelist_wrfile  = {
50     &krb5_ktf_writable_ops,
51     0
52 };
53 /* Solaris Kerberos */
54 static const  struct krb5_kt_typelist krb5_kt_typelist_file  = {
55     &krb5_ktf_ops,
56     &krb5_kt_typelist_wrfile
57 };
58 /* Solaris Kerberos */
59 static const struct krb5_kt_typelist krb5_kt_typelist_srvtab = {
60     &krb5_kts_ops,
61     &krb5_kt_typelist_file
62 };
63 static const struct krb5_kt_typelist *kt_typehead = &krb5_kt_typelist_srvtab;
64 /* Lock for protecting the type list.  */
65 static k5_mutex_t kt_typehead_lock = K5_MUTEX_PARTIAL_INITIALIZER;
66 
krb5int_kt_initialize(void)67 int krb5int_kt_initialize(void)
68 {
69     return k5_mutex_finish_init(&kt_typehead_lock);
70 }
71 
72 void
krb5int_kt_finalize(void)73 krb5int_kt_finalize(void)
74 {
75     struct krb5_kt_typelist *t, *t_next;
76     k5_mutex_destroy(&kt_typehead_lock);
77     /* Solaris Kerberos */
78     for (t = (struct krb5_kt_typelist *)kt_typehead; t != &krb5_kt_typelist_srvtab;
79 	t = t_next) {
80         t_next = (struct krb5_kt_typelist *)t->next;
81 	free(t);
82     }
83 }
84 
85 
86 /*
87  * Register a new key table type
88  * don't replace if it already exists; return an error instead.
89  */
90 /*ARGSUSED*/
91 krb5_error_code KRB5_CALLCONV
krb5_kt_register(krb5_context context,const krb5_kt_ops * ops)92 krb5_kt_register(krb5_context context, const krb5_kt_ops *ops)
93 {
94     const struct krb5_kt_typelist *t;
95     struct krb5_kt_typelist *newt;
96     krb5_error_code err;
97 
98     err = k5_mutex_lock(&kt_typehead_lock);
99     if (err)
100 	return err;
101     for (t = kt_typehead; t && strcmp(t->ops->prefix,ops->prefix);t = t->next)
102 	;
103     if (t) {
104 	k5_mutex_unlock(&kt_typehead_lock);
105 	return KRB5_KT_TYPE_EXISTS;
106     }
107     if (!(newt = (struct krb5_kt_typelist *) malloc(sizeof(*t)))) {
108 	k5_mutex_unlock(&kt_typehead_lock);
109 	return ENOMEM;
110     }
111     newt->next = kt_typehead;
112     newt->ops = ops;
113     kt_typehead = newt;
114     k5_mutex_unlock(&kt_typehead_lock);
115     return 0;
116 }
117 
118 /*
119  * Resolve a key table name into a keytab object.
120  *
121  * The name is currently constrained to be of the form "type:residual";
122  *
123  * The "type" portion corresponds to one of the registered key table
124  * types, while the "residual" portion is specific to the
125  * particular keytab type.
126  */
127 
128 #include <ctype.h>
129 krb5_error_code KRB5_CALLCONV
krb5_kt_resolve(krb5_context context,const char * name,krb5_keytab * ktid)130 krb5_kt_resolve (krb5_context context, const char *name, krb5_keytab *ktid)
131 {
132     const struct krb5_kt_typelist *tlist;
133     char *pfx;
134     unsigned int pfxlen;
135     const char *cp, *resid;
136     krb5_error_code err;
137 
138     cp = strchr (name, ':');
139     if (!cp) {
140 	    return (*krb5_kt_dfl_ops.resolve)(context, name, ktid);
141     }
142 
143     pfxlen = cp - name;
144 
145     if ( pfxlen == 1 && isalpha((unsigned char) name[0]) ) {
146         /* We found a drive letter not a prefix - use FILE */
147         pfx = strdup("FILE");
148         if (!pfx)
149             return ENOMEM;
150 
151         resid = name;
152     } else {
153         resid = name + pfxlen + 1;
154 
155         pfx = malloc (pfxlen+1);
156         if (!pfx)
157             return ENOMEM;
158 
159         memcpy (pfx, name, pfxlen);
160         pfx[pfxlen] = '\0';
161     }
162 
163     *ktid = (krb5_keytab) 0;
164 
165     err = k5_mutex_lock(&kt_typehead_lock);
166     if (err)
167 	return err;
168     tlist = kt_typehead;
169     /* Don't need to hold the lock, since entries are never modified
170        or removed once they're in the list.  Just need to protect
171        access to the list head variable itself.  */
172     k5_mutex_unlock(&kt_typehead_lock);
173     for (; tlist; tlist = tlist->next) {
174 	if (strcmp (tlist->ops->prefix, pfx) == 0) {
175 	    free(pfx);
176 	    return (*tlist->ops->resolve)(context, resid, ktid);
177 	}
178     }
179     free(pfx);
180     return KRB5_KT_UNKNOWN_TYPE;
181 }
182 
183 /*
184  * Routines to deal with externalizingt krb5_keytab.
185  *	krb5_keytab_size();
186  *	krb5_keytab_externalize();
187  *	krb5_keytab_internalize();
188  */
189 static krb5_error_code krb5_keytab_size
190 	(krb5_context, krb5_pointer, size_t *);
191 static krb5_error_code krb5_keytab_externalize
192 	(krb5_context, krb5_pointer, krb5_octet **, size_t *);
193 static krb5_error_code krb5_keytab_internalize
194 	(krb5_context,krb5_pointer *, krb5_octet **, size_t *);
195 
196 /*
197  * Serialization entry for this type.
198  */
199 static const krb5_ser_entry krb5_keytab_ser_entry = {
200     KV5M_KEYTAB,			/* Type			*/
201     krb5_keytab_size,			/* Sizer routine	*/
202     krb5_keytab_externalize,		/* Externalize routine	*/
203     krb5_keytab_internalize		/* Internalize routine	*/
204 };
205 
206 static krb5_error_code
krb5_keytab_size(krb5_context kcontext,krb5_pointer arg,size_t * sizep)207 krb5_keytab_size(krb5_context kcontext, krb5_pointer arg, size_t *sizep)
208 {
209     krb5_error_code	kret;
210     krb5_keytab		keytab;
211     krb5_ser_handle	shandle;
212 
213     kret = EINVAL;
214     /* Solaris Kerberos */
215     keytab = (krb5_keytab) arg;
216     shandle = (krb5_ser_handle) keytab->ops->serializer;
217     if ((keytab != NULL) && (keytab->ops) &&
218 	(shandle != NULL) && (shandle->sizer))
219 	kret = (*shandle->sizer)(kcontext, arg, sizep);
220     return(kret);
221 }
222 
223 static krb5_error_code
krb5_keytab_externalize(krb5_context kcontext,krb5_pointer arg,krb5_octet ** buffer,size_t * lenremain)224 krb5_keytab_externalize(krb5_context kcontext, krb5_pointer arg, krb5_octet **buffer, size_t *lenremain)
225 {
226     krb5_error_code	kret;
227     krb5_keytab		keytab;
228     krb5_ser_handle	shandle;
229 
230     kret = EINVAL;
231     /* Solaris Kerberos */
232     keytab = (krb5_keytab) arg;
233     shandle = (krb5_ser_handle) keytab->ops->serializer;
234     if ((keytab != NULL) && (keytab->ops) &&
235 	(shandle != NULL) && (shandle->externalizer))
236 	kret = (*shandle->externalizer)(kcontext, arg, buffer, lenremain);
237     return(kret);
238 }
239 
240 static krb5_error_code
krb5_keytab_internalize(krb5_context kcontext,krb5_pointer * argp,krb5_octet ** buffer,size_t * lenremain)241 krb5_keytab_internalize(krb5_context kcontext, krb5_pointer *argp, krb5_octet **buffer, size_t *lenremain)
242 {
243     krb5_error_code	kret;
244     krb5_ser_handle	shandle;
245 
246     kret = EINVAL;
247     /* Solaris Kerberos */
248     shandle = (krb5_ser_handle) krb5_kt_dfl_ops.serializer;
249     if ((shandle != NULL) && (shandle->internalizer))
250 	kret = (*shandle->internalizer)(kcontext, argp, buffer, lenremain);
251     return(kret);
252 }
253 
254 krb5_error_code KRB5_CALLCONV
krb5_ser_keytab_init(krb5_context kcontext)255 krb5_ser_keytab_init(krb5_context kcontext)
256 {
257     return(krb5_register_serializer(kcontext, &krb5_keytab_ser_entry));
258 }
259