| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Packing and unpacking key data |
| 4 | * |
| 5 | * (c) 1999 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Catacomb. |
| 11 | * |
| 12 | * Catacomb is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with Catacomb; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | /*----- Header files ------------------------------------------------------*/ |
| 29 | |
| 30 | #include <mLib/dstr.h> |
| 31 | |
| 32 | #include "key-data.h" |
| 33 | |
| 34 | /*----- Generic packing and unpacking -------------------------------------*/ |
| 35 | |
| 36 | /* --- @key_pack@ --- * |
| 37 | * |
| 38 | * Arguments: @key_packdef *kp@ = pointer to packing structure |
| 39 | * @key_data **kd@ = where to put the key data pointer |
| 40 | * @dstr *d@ = pointer to tag string for the key data |
| 41 | * |
| 42 | * Returns: Error code, or zero. |
| 43 | * |
| 44 | * Use: Packs a key from a data structure. |
| 45 | */ |
| 46 | |
| 47 | int key_pack(key_packdef *kp, key_data **kd, dstr *d) |
| 48 | { |
| 49 | switch (kp->e & KF_ENCMASK) { |
| 50 | |
| 51 | /* --- Binary and integer keys are easy --- */ |
| 52 | |
| 53 | case KENC_BINARY: { |
| 54 | key_bin *b = kp->p; |
| 55 | *kd = key_newbinary(kp->e, b->k, b->sz); |
| 56 | return (0); |
| 57 | } |
| 58 | case KENC_MP: |
| 59 | *kd = key_newmp(kp->e, *(mp **)kp->p); |
| 60 | return (0); |
| 61 | case KENC_STRING: |
| 62 | *kd = key_newstring(kp->e, *(char **)kp->p); |
| 63 | return (0); |
| 64 | case KENC_EC: |
| 65 | *kd = key_newec(kp->e, (ec *)kp->p); |
| 66 | return (0); |
| 67 | |
| 68 | /* --- Encrypted keys are a little tricky --- * |
| 69 | * |
| 70 | * This works rather differently to unpacking. |
| 71 | */ |
| 72 | |
| 73 | case KENC_ENCRYPT: { |
| 74 | key_data *kkd; |
| 75 | int err = key_pack(kp->p, &kkd, d); |
| 76 | if (!err) { |
| 77 | err = key_plock(kd, kkd, d->buf); |
| 78 | key_drop(kkd); |
| 79 | } |
| 80 | return (err); |
| 81 | } |
| 82 | |
| 83 | /* --- Structured keys, as ever, are a nuisance --- */ |
| 84 | |
| 85 | case KENC_STRUCT: { |
| 86 | int err; |
| 87 | key_packstruct *p; |
| 88 | size_t l = d->len; |
| 89 | |
| 90 | *kd = key_newstruct(); |
| 91 | DPUTC(d, '.'); |
| 92 | for (p = kp->p; p->name; p++) { |
| 93 | key_data *kkd; |
| 94 | d->len = l + 1; |
| 95 | DPUTS(d, p->name); |
| 96 | if ((err = key_pack(&p->kp, &kkd, d)) != 0) { |
| 97 | key_drop(*kd); |
| 98 | return (err); |
| 99 | } |
| 100 | key_structsteal(*kd, p->name, kkd); |
| 101 | } |
| 102 | d->len = l; |
| 103 | d->buf[l] = 0; |
| 104 | return (0); |
| 105 | } |
| 106 | default: |
| 107 | abort(); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | /* --- @key_unpack@ --- * |
| 112 | * |
| 113 | * Arguments: @key_packdef *kp@ = pointer to packing structure |
| 114 | * @key_data *kd@ = pointer to source key data |
| 115 | * @dstr *d@ = pointer to tag string for the key data |
| 116 | * |
| 117 | * Returns: Error code, or zero. |
| 118 | * |
| 119 | * Use: Unpacks a key into an appropriate data structure. |
| 120 | */ |
| 121 | |
| 122 | int key_unpack(key_packdef *kp, key_data *kd, dstr *d) |
| 123 | { |
| 124 | unsigned e = kp->e & KF_ENCMASK; |
| 125 | int err; |
| 126 | |
| 127 | /* --- Decrypt the encrypted key --- */ |
| 128 | |
| 129 | if ((kd->e & KF_ENCMASK) == KENC_ENCRYPT) { |
| 130 | if ((err = key_punlock(&kp->kd, kd, d->buf)) != 0) |
| 131 | goto fail; |
| 132 | kd = kp->kd; |
| 133 | } |
| 134 | |
| 135 | /* --- Ensure that the key has the right type --- */ |
| 136 | |
| 137 | if ((kd->e & KF_ENCMASK) != e) { |
| 138 | err = KERR_WRONGTYPE; |
| 139 | goto fail; |
| 140 | } |
| 141 | |
| 142 | /* --- Unpack the key --- * |
| 143 | * |
| 144 | * Only three possibilities left now. |
| 145 | */ |
| 146 | |
| 147 | switch (e) { |
| 148 | |
| 149 | /* --- Binary and integer keys are easy --- */ |
| 150 | |
| 151 | case KENC_BINARY: |
| 152 | *(key_bin *)kp->p = kd->u.k; |
| 153 | break; |
| 154 | case KENC_MP: |
| 155 | *(mp **)kp->p = kd->u.m; |
| 156 | break; |
| 157 | case KENC_STRING: |
| 158 | *(char **)kp->p = kd->u.p; |
| 159 | break; |
| 160 | case KENC_EC: |
| 161 | *(ec *)kp->p = kd->u.e; |
| 162 | break; |
| 163 | |
| 164 | /* --- Structured keys take a little care --- */ |
| 165 | |
| 166 | case KENC_STRUCT: { |
| 167 | key_packstruct *p, *q; |
| 168 | size_t l = d->len; |
| 169 | |
| 170 | /* --- Iterate over the requested subparts --- */ |
| 171 | |
| 172 | DPUTC(d, '.'); |
| 173 | for (p = kp->p; p->name; p++) { |
| 174 | key_data *kkd; |
| 175 | |
| 176 | /* --- Build the name --- */ |
| 177 | |
| 178 | d->len = l + 1; |
| 179 | DPUTS(d, p->name); |
| 180 | |
| 181 | /* --- Find and unpack the subkey --- */ |
| 182 | |
| 183 | if ((kkd = key_structfind(kd, p->name)) == 0) { |
| 184 | if (!(p->kp.e & KF_OPT)) { |
| 185 | err = KERR_NOTFOUND; |
| 186 | goto tidy; |
| 187 | } |
| 188 | } else if ((err = key_unpack(&p->kp, kkd, d)) != 0) { |
| 189 | p++; |
| 190 | goto tidy; |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | /* --- Done --- */ |
| 195 | |
| 196 | d->len = l; |
| 197 | d->buf[l] = 0; |
| 198 | break; |
| 199 | |
| 200 | /* --- Tidy up if something went wrong --- */ |
| 201 | |
| 202 | tidy: |
| 203 | for (q = kp->p; q < p; q++) |
| 204 | key_unpackdone(&q->kp); |
| 205 | goto fail; |
| 206 | } |
| 207 | |
| 208 | default: |
| 209 | abort(); |
| 210 | } |
| 211 | |
| 212 | return (0); |
| 213 | |
| 214 | /* --- Something went wrong --- */ |
| 215 | |
| 216 | fail: |
| 217 | if (kp->kd) { |
| 218 | key_drop(kp->kd); |
| 219 | kp->kd = 0; |
| 220 | } |
| 221 | return (err); |
| 222 | } |
| 223 | |
| 224 | /* --- @key_unpackdone@ --- * |
| 225 | * |
| 226 | * Arguments: @key_packdef *kp@ = pointer to packing definition |
| 227 | * |
| 228 | * Returns: --- |
| 229 | * |
| 230 | * Use: Frees the key components contained within a packing |
| 231 | * definition, created during key unpacking. |
| 232 | */ |
| 233 | |
| 234 | void key_unpackdone(key_packdef *kp) |
| 235 | { |
| 236 | if (kp->kd) { |
| 237 | key_drop(kp->kd); |
| 238 | kp->kd = 0; |
| 239 | } |
| 240 | if ((kp->e & KF_ENCMASK) == KENC_STRUCT) { |
| 241 | key_packstruct *p; |
| 242 | for (p = kp->p; p->name; p++) |
| 243 | key_unpackdone(&p->kp); |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | /*----- That's all, folks -------------------------------------------------*/ |