e56dff91 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: key-pack.c,v 1.1 2000/06/17 10:42:41 mdw Exp $ |
4 | * |
5 | * Packing and unpacking key data |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of Catacomb. |
13 | * |
14 | * Catacomb is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU Library General Public License as |
16 | * published by the Free Software Foundation; either version 2 of the |
17 | * License, or (at your option) any later version. |
18 | * |
19 | * Catacomb is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU Library General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU Library General Public |
25 | * License along with Catacomb; if not, write to the Free |
26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
27 | * MA 02111-1307, USA. |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: key-pack.c,v $ |
33 | * Revision 1.1 2000/06/17 10:42:41 mdw |
34 | * Packing and unpacking structured keys. |
35 | * |
36 | */ |
37 | |
38 | /*----- Header files ------------------------------------------------------*/ |
39 | |
40 | #include <mLib/dstr.h> |
41 | |
42 | #include "key.h" |
43 | #include "key-data.h" |
44 | |
45 | /*----- Generic packing and unpacking -------------------------------------*/ |
46 | |
47 | /* --- @key_pack@ --- * |
48 | * |
49 | * Arguments: @key_packdef *kp@ = pointer to packing structure |
50 | * @key_data *kd@ = pointer to destination key data |
51 | * @dstr *d@ = pointer to tag string for the key data |
52 | * |
53 | * Returns: Error code, or zero. |
54 | * |
55 | * Use: Packs a key from a data structure. |
56 | */ |
57 | |
58 | int key_pack(key_packdef *kp, key_data *kd, dstr *d) |
59 | { |
60 | switch (kp->kd.e & KF_ENCMASK) { |
61 | |
62 | /* --- Binary and integer keys are easy --- */ |
63 | |
64 | case KENC_BINARY: |
65 | kd->u.k = *(key_bin *)kp->p; |
66 | return (0); |
67 | case KENC_MP: |
68 | kd->u.m = *(mp **)kp->p; |
69 | return (0); |
70 | |
71 | /* --- Encrypted keys are a little tricky --- * |
72 | * |
73 | * This works rather differently to unpacking. |
74 | */ |
75 | |
76 | case KENC_ENCRYPT: { |
77 | key_data kkd; |
78 | int err = key_pack(kp->p, &kkd, d); |
79 | if (!err) { |
80 | if (key_plock(d->buf, &kkd, kd)) |
81 | err = KERR_BADPASS; |
82 | key_destroy(&kkd); |
83 | } |
84 | return (err); |
85 | } |
86 | |
87 | /* --- Structured keys, as ever, are a nuisance --- */ |
88 | |
89 | case KENC_STRUCT: { |
90 | int err; |
91 | key_packstruct *p; |
92 | size_t l = d->len; |
93 | |
94 | key_structure(kd); |
95 | DPUTC(d, '.'); |
96 | for (p = kp->p; p->name; p++) { |
97 | key_data *kkd; |
98 | d->len = l + 1; |
99 | DPUTS(d, p->name); |
100 | kkd = key_structcreate(kd, p->name); |
101 | if ((err = key_pack(&p->kp, kkd, d)) != 0) { |
102 | key_destroy(kd); |
103 | return (err); |
104 | } |
105 | } |
106 | d->len = l; |
107 | d->buf[l] = 0; |
108 | return (0); |
109 | } |
110 | } |
111 | |
112 | return (KERR_BADTYPE); |
113 | } |
114 | |
115 | /* --- @key_unpack@ --- * |
116 | * |
117 | * Arguments: @key_packdef *kp@ = pointer to packing structure |
118 | * @key_data *kd@ = pointer to source key data |
119 | * @dstr *d@ = pointer to tag string for the key data |
120 | * |
121 | * Returns: Error code, or zero. |
122 | * |
123 | * Use: Unpacks a key into an appropriate data structure. |
124 | */ |
125 | |
126 | int key_unpack(key_packdef *kp, key_data *kd, dstr *d) |
127 | { |
128 | unsigned e = kp->kd.e & KF_ENCMASK; |
129 | int err; |
130 | |
131 | /* --- Decrypt the encrypted key --- */ |
132 | |
133 | while ((kd->e & KF_ENCMASK) == KENC_ENCRYPT) { |
134 | if (key_punlock(d->buf, kd, &kp->kd)) { |
135 | err = KERR_BADPASS; |
136 | goto fail; |
137 | } |
138 | kd = &kp->kd; |
139 | kd->e |= KF_TEMP; |
140 | } |
141 | |
142 | /* --- Ensure that the key has the right type --- */ |
143 | |
144 | if ((kd->e & KF_ENCMASK) != e) { |
145 | err = KERR_BADTYPE; |
146 | goto fail; |
147 | } |
148 | |
149 | /* --- Unpack the key --- * |
150 | * |
151 | * Only three possibilities left now. |
152 | */ |
153 | |
154 | switch (e) { |
155 | |
156 | /* --- Binary and integer keys are easy --- */ |
157 | |
158 | case KENC_BINARY: |
159 | *(key_bin *)kp->p = kd->u.k; |
160 | break; |
161 | case KENC_MP: |
162 | *(mp **)kp->p = kd->u.m; |
163 | break; |
164 | |
165 | /* --- Structured keys take a little care --- */ |
166 | |
167 | case KENC_STRUCT: { |
168 | key_packstruct *p, *q; |
169 | size_t l = d->len; |
170 | |
171 | /* --- Iterate over the requested subparts --- */ |
172 | |
173 | DPUTC(d, '.'); |
174 | for (p = kp->p; p->name; p++) { |
175 | key_data *kkd; |
176 | |
177 | /* --- Build the name --- */ |
178 | |
179 | d->len = l + 1; |
180 | DPUTS(d, p->name); |
181 | |
182 | /* --- Find and unpack the subkey --- */ |
183 | |
184 | if ((kkd = key_structfind(kd, p->name)) == 0) { |
185 | if (!(p->kp.kd.e & KF_OPT)) { |
186 | err = KERR_NOTFOUND; |
187 | goto tidy; |
188 | } |
189 | } else if ((err = key_unpack(&p->kp, kkd, d)) != 0) { |
190 | p++; |
191 | goto tidy; |
192 | } |
193 | } |
194 | |
195 | /* --- Done --- */ |
196 | |
197 | d->len = l; |
198 | d->buf[l] = 0; |
199 | break; |
200 | |
201 | /* --- Tidy up if something went wrong --- */ |
202 | |
203 | tidy: |
204 | for (q = kp->p; q < p; q++) |
205 | key_unpackdone(&q->kp); |
206 | goto fail; |
207 | } |
208 | } |
209 | |
210 | return (0); |
211 | |
212 | /* --- Something went wrong --- */ |
213 | |
214 | fail: |
215 | if (kd == &kp->kd) |
216 | key_destroy(kd); |
217 | return (err); |
218 | } |
219 | |
220 | /* --- @key_unpackdone@ --- * |
221 | * |
222 | * Arguments: @key_packdef *kp@ = pointer to packing definition |
223 | * |
224 | * Returns: --- |
225 | * |
226 | * Use: Frees the key components contained within a packing |
227 | * definition, created during key unpacking. |
228 | */ |
229 | |
230 | void key_unpackdone(key_packdef *kp) |
231 | { |
232 | if (kp->kd.e & KF_TEMP) |
233 | key_destroy(&kp->kd); |
234 | if ((kp->kd.e & KF_ENCMASK) == KENC_STRUCT) { |
235 | key_packstruct *p; |
236 | for (p = kp->p; p->name; p++) |
237 | key_unpackdone(&p->kp); |
238 | } |
239 | } |
240 | |
241 | /*----- That's all, folks -------------------------------------------------*/ |