Mercurial > dropbear

comparison keyimport.c @ 1308:8678e2cc1e53

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
make indenting consistent
author Matt Johnston <matt@ucc.asn.au>
date Tue, 12 Jul 2016 23:33:15 +0800
parents ad9c40aca3bc
children 2c9dac2d6707
comparison
equal deleted inserted replaced
1307:ad9c40aca3bc 1308:8678e2cc1e53
45 (cp)[2] = (unsigned char)((value) >> 8); \ 45 (cp)[2] = (unsigned char)((value) >> 8); \
46 (cp)[1] = (unsigned char)((value) >> 16); \ 46 (cp)[1] = (unsigned char)((value) >> 16); \
47 (cp)[0] = (unsigned char)((value) >> 24); } while (0) 47 (cp)[0] = (unsigned char)((value) >> 24); } while (0)
48 48
49 #define GET_32BIT(cp) \ 49 #define GET_32BIT(cp) \
50 (((unsigned long)(unsigned char)(cp)[0] << 24) | \ 50 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
51 ((unsigned long)(unsigned char)(cp)[1] << 16) | \ 51 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
52 ((unsigned long)(unsigned char)(cp)[2] << 8) | \ 52 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
53 ((unsigned long)(unsigned char)(cp)[3])) 53 ((unsigned long)(unsigned char)(cp)[3]))
54 54
55 static int openssh_encrypted(const char *filename); 55 static int openssh_encrypted(const char *filename);
56 static sign_key *openssh_read(const char *filename, char *passphrase); 56 static sign_key *openssh_read(const char *filename, char *passphrase);
57 static int openssh_write(const char *filename, sign_key *key, 57 static int openssh_write(const char *filename, sign_key *key,
58 char *passphrase); 58 char *passphrase);
59 59
60 static int dropbear_write(const char*filename, sign_key * key); 60 static int dropbear_write(const char*filename, sign_key * key);
61 static sign_key *dropbear_read(const char* filename); 61 static sign_key *dropbear_read(const char* filename);
62 62
63 static int toint(unsigned u); 63 static int toint(unsigned u);
64 64
65 #if 0 65 #if 0
66 static int sshcom_encrypted(const char *filename, char **comment); 66 static int sshcom_encrypted(const char *filename, char **comment);
67 static struct ssh2_userkey *sshcom_read(const char *filename, char *passphrase); 67 static struct ssh2_userkey *sshcom_read(const char *filename, char *passphrase);
68 static int sshcom_write(const char *filename, struct ssh2_userkey *key, 68 static int sshcom_write(const char *filename, struct ssh2_userkey *key,
69 char *passphrase); 69 char *passphrase);
70 #endif 70 #endif
71 71
72 int import_encrypted(const char* filename, int filetype) { 72 int import_encrypted(const char* filename, int filetype) {
73 73
74 if (filetype == KEYFILE_OPENSSH) { 74 if (filetype == KEYFILE_OPENSSH) {
75 return openssh_encrypted(filename); 75 return openssh_encrypted(filename);
76 #if 0 76 #if 0
77 } else if (filetype == KEYFILE_SSHCOM) { 77 } else if (filetype == KEYFILE_SSHCOM) {
78 return sshcom_encrypted(filename, NULL); 78 return sshcom_encrypted(filename, NULL);
79 #endif 79 #endif
80 } 80 }
81 return 0; 81 return 0;
82 } 82 }
83 83
84 sign_key *import_read(const char *filename, char *passphrase, int filetype) { 84 sign_key *import_read(const char *filename, char *passphrase, int filetype) {
85 85
86 if (filetype == KEYFILE_OPENSSH) { 86 if (filetype == KEYFILE_OPENSSH) {
87 return openssh_read(filename, passphrase); 87 return openssh_read(filename, passphrase);
88 } else if (filetype == KEYFILE_DROPBEAR) { 88 } else if (filetype == KEYFILE_DROPBEAR) {
89 return dropbear_read(filename); 89 return dropbear_read(filename);
90 #if 0 90 #if 0
91 } else if (filetype == KEYFILE_SSHCOM) { 91 } else if (filetype == KEYFILE_SSHCOM) {
92 return sshcom_read(filename, passphrase); 92 return sshcom_read(filename, passphrase);
93 #endif 93 #endif
94 } 94 }
95 return NULL;
96 }
97
98 int import_write(const char *filename, sign_key *key, char *passphrase,
99 int filetype) {
100
101 if (filetype == KEYFILE_OPENSSH) {
102 return openssh_write(filename, key, passphrase);
103 } else if (filetype == KEYFILE_DROPBEAR) {
104 return dropbear_write(filename, key);
105 #if 0
106 } else if (filetype == KEYFILE_SSHCOM) {
107 return sshcom_write(filename, key, passphrase);
108 #endif
109 }
110 return 0;
111 }
112
113 static sign_key *dropbear_read(const char* filename) {
114
115 buffer * buf = NULL;
116 sign_key *ret = NULL;
117 enum signkey_type type;
118
119 buf = buf_new(MAX_PRIVKEY_SIZE);
120 if (buf_readfile(buf, filename) == DROPBEAR_FAILURE) {
121 goto error;
122 }
123
124 buf_setpos(buf, 0);
125 ret = new_sign_key();
126
127 type = DROPBEAR_SIGNKEY_ANY;
128 if (buf_get_priv_key(buf, ret, &type) == DROPBEAR_FAILURE){
129 goto error;
130 }
131 buf_free(buf);
132
133 ret->type = type;
134
135 return ret;
136
137 error:
138 if (buf) {
139 buf_free(buf);
140 }
141 if (ret) {
142 sign_key_free(ret);
143 }
144 return NULL; 95 return NULL;
145 } 96 }
146 97
98 int import_write(const char *filename, sign_key *key, char *passphrase,
99 int filetype) {
100
101 if (filetype == KEYFILE_OPENSSH) {
102 return openssh_write(filename, key, passphrase);
103 } else if (filetype == KEYFILE_DROPBEAR) {
104 return dropbear_write(filename, key);
105 #if 0
106 } else if (filetype == KEYFILE_SSHCOM) {
107 return sshcom_write(filename, key, passphrase);
108 #endif
109 }
110 return 0;
111 }
112
113 static sign_key *dropbear_read(const char* filename) {
114
115 buffer * buf = NULL;
116 sign_key *ret = NULL;
117 enum signkey_type type;
118
119 buf = buf_new(MAX_PRIVKEY_SIZE);
120 if (buf_readfile(buf, filename) == DROPBEAR_FAILURE) {
121 goto error;
122 }
123
124 buf_setpos(buf, 0);
125 ret = new_sign_key();
126
127 type = DROPBEAR_SIGNKEY_ANY;
128 if (buf_get_priv_key(buf, ret, &type) == DROPBEAR_FAILURE){
129 goto error;
130 }
131 buf_free(buf);
132
133 ret->type = type;
134
135 return ret;
136
137 error:
138 if (buf) {
139 buf_free(buf);
140 }
141 if (ret) {
142 sign_key_free(ret);
143 }
144 return NULL;
145 }
146
147 /* returns 0 on fail, 1 on success */ 147 /* returns 0 on fail, 1 on success */
148 static int dropbear_write(const char*filename, sign_key * key) { 148 static int dropbear_write(const char*filename, sign_key * key) {
149 149
150 buffer * buf; 150 buffer * buf;
151 FILE*fp; 151 FILE*fp;
152 int len; 152 int len;
153 int ret; 153 int ret;
154 154
155 buf = buf_new(MAX_PRIVKEY_SIZE); 155 buf = buf_new(MAX_PRIVKEY_SIZE);
156 buf_put_priv_key(buf, key, key->type); 156 buf_put_priv_key(buf, key, key->type);
157 157
158 fp = fopen(filename, "w"); 158 fp = fopen(filename, "w");
159 if (!fp) { 159 if (!fp) {
160 ret = 0; 160 ret = 0;
161 goto out; 161 goto out;
162 } 162 }
163 163
164 buf_setpos(buf, 0); 164 buf_setpos(buf, 0);
165 do { 165 do {
166 len = fwrite(buf_getptr(buf, buf->len - buf->pos), 166 len = fwrite(buf_getptr(buf, buf->len - buf->pos),
167 1, buf->len - buf->pos, fp); 167 1, buf->len - buf->pos, fp);
168 buf_incrpos(buf, len); 168 buf_incrpos(buf, len);
169 } while (len > 0 && buf->len != buf->pos); 169 } while (len > 0 && buf->len != buf->pos);
170 170
171 fclose(fp); 171 fclose(fp);
172 172
173 if (buf->pos != buf->len) { 173 if (buf->pos != buf->len) {
174 ret = 0; 174 ret = 0;
175 } else { 175 } else {
176 ret = 1; 176 ret = 1;
177 } 177 }
178 out: 178 out:
179 buf_free(buf); 179 buf_free(buf);
180 return ret; 180 return ret;
181 } 181 }
182 182
183 183
184 /* ---------------------------------------------------------------------- 184 /* ----------------------------------------------------------------------
185 * Helper routines. (The base64 ones are defined in sshpubk.c.) 185 * Helper routines. (The base64 ones are defined in sshpubk.c.)
186 */ 186 */
187 187
188 #define isbase64(c) ( ((c) >= 'A' && (c) <= 'Z') || \ 188 #define isbase64(c) ( ((c) >= 'A' && (c) <= 'Z') || \
189 ((c) >= 'a' && (c) <= 'z') || \ 189 ((c) >= 'a' && (c) <= 'z') || \
190 ((c) >= '0' && (c) <= '9') || \ 190 ((c) >= '0' && (c) <= '9') || \
191 (c) == '+' || (c) == '/' || (c) == '=' \ 191 (c) == '+' || (c) == '/' || (c) == '=' \
192 ) 192 )
193 193
194 /* cpl has to be less than 100 */ 194 /* cpl has to be less than 100 */
195 static void base64_encode_fp(FILE * fp, unsigned char *data, 195 static void base64_encode_fp(FILE * fp, unsigned char *data,
196 int datalen, int cpl) 196 int datalen, int cpl)
197 { 197 {
198 unsigned char out[100]; 198 unsigned char out[100];
199 int n; 199 int n;
200 unsigned long outlen; 200 unsigned long outlen;
201 int rawcpl; 201 int rawcpl;
202 rawcpl = cpl * 3 / 4; 202 rawcpl = cpl * 3 / 4;
203 dropbear_assert((unsigned int)cpl < sizeof(out)); 203 dropbear_assert((unsigned int)cpl < sizeof(out));
204 204
205 while (datalen > 0) { 205 while (datalen > 0) {
206 n = (datalen < rawcpl ? datalen : rawcpl); 206 n = (datalen < rawcpl ? datalen : rawcpl);
207 outlen = sizeof(out); 207 outlen = sizeof(out);
208 base64_encode(data, n, out, &outlen); 208 base64_encode(data, n, out, &outlen);
209 data += n; 209 data += n;
210 datalen -= n; 210 datalen -= n;
211 fwrite(out, 1, outlen, fp); 211 fwrite(out, 1, outlen, fp);
212 fputc('\n', fp); 212 fputc('\n', fp);
213 } 213 }
214 } 214 }
215 /* 215 /*
216 * Read an ASN.1/BER identifier and length pair. 216 * Read an ASN.1/BER identifier and length pair.
217 * 217 *
218 * Flags are a combination of the #defines listed below. 218 * Flags are a combination of the #defines listed below.
230 230
231 /* Primitive versus constructed bit. */ 231 /* Primitive versus constructed bit. */
232 #define ASN1_CONSTRUCTED (1 << 5) 232 #define ASN1_CONSTRUCTED (1 << 5)
233 233
234 static int ber_read_id_len(void *source, int sourcelen, 234 static int ber_read_id_len(void *source, int sourcelen,
235 int *id, int *length, int *flags) 235 int *id, int *length, int *flags)
236 { 236 {
237 unsigned char *p = (unsigned char *) source; 237 unsigned char *p = (unsigned char *) source;
238 238
239 if (sourcelen == 0) 239 if (sourcelen == 0)
240 return -1;
241
242 *flags = (*p & 0xE0);
243 if ((*p & 0x1F) == 0x1F) {
244 *id = 0;
245 while (*p & 0x80) {
246 p++, sourcelen--;
247 if (sourcelen == 0)
248 return -1; 240 return -1;
249 *id = (*id << 7) | (*p & 0x7F); 241
250 } 242 *flags = (*p & 0xE0);
251 p++, sourcelen--; 243 if ((*p & 0x1F) == 0x1F) {
252 } else { 244 *id = 0;
253 *id = *p & 0x1F; 245 while (*p & 0x80) {
254 p++, sourcelen--; 246 p++, sourcelen--;
255 } 247 if (sourcelen == 0)
256 248 return -1;
257 if (sourcelen == 0) 249 *id = (*id << 7) | (*p & 0x7F);
258 return -1; 250 }
259 251 p++, sourcelen--;
260 if (*p & 0x80) { 252 } else {
261 unsigned len; 253 *id = *p & 0x1F;
262 int n = *p & 0x7F; 254 p++, sourcelen--;
263 p++, sourcelen--; 255 }
264 if (sourcelen < n) 256
265 return -1; 257 if (sourcelen == 0)
266 len = 0; 258 return -1;
267 while (n--) 259
268 len = (len << 8) | (*p++); 260 if (*p & 0x80) {
269 sourcelen -= n; 261 unsigned len;
270 *length = toint(len); 262 int n = *p & 0x7F;
271 } else { 263 p++, sourcelen--;
272 *length = *p; 264 if (sourcelen < n)
273 p++, sourcelen--; 265 return -1;
274 } 266 len = 0;
275 267 while (n--)
276 if (*length < 0) { 268 len = (len << 8) | (*p++);
277 printf("Negative ASN.1 length\n"); 269 sourcelen -= n;
278 return -1; 270 *length = toint(len);
279 } 271 } else {
280 272 *length = *p;
281 return p - (unsigned char *) source; 273 p++, sourcelen--;
274 }
275
276 if (*length < 0) {
277 printf("Negative ASN.1 length\n");
278 return -1;
279 }
280
281 return p - (unsigned char *) source;
282 } 282 }
283 283
284 /* 284 /*
285 * Write an ASN.1/BER identifier and length pair. Returns the 285 * Write an ASN.1/BER identifier and length pair. Returns the
286 * number of bytes consumed. Assumes dest contains enough space. 286 * number of bytes consumed. Assumes dest contains enough space.
287 * Will avoid writing anything if dest is NULL, but still return 287 * Will avoid writing anything if dest is NULL, but still return
288 * amount of space required. 288 * amount of space required.
289 */ 289 */
290 static int ber_write_id_len(void *dest, int id, int length, int flags) 290 static int ber_write_id_len(void *dest, int id, int length, int flags)
291 { 291 {
292 unsigned char *d = (unsigned char *)dest; 292 unsigned char *d = (unsigned char *)dest;
293 int len = 0; 293 int len = 0;
294 294
295 if (id <= 30) { 295 if (id <= 30) {
296 /* 296 /*
297 * Identifier is one byte. 297 * Identifier is one byte.
298 */ 298 */
299 len++; 299 len++;
300 if (d) *d++ = id | flags; 300 if (d) *d++ = id | flags;
301 } else { 301 } else {
302 int n; 302 int n;
303 /* 303 /*
304 * Identifier is multiple bytes: the first byte is 11111 304 * Identifier is multiple bytes: the first byte is 11111
305 * plus the flags, and subsequent bytes encode the value of 305 * plus the flags, and subsequent bytes encode the value of
306 * the identifier, 7 bits at a time, with the top bit of 306 * the identifier, 7 bits at a time, with the top bit of
307 * each byte 1 except the last one which is 0. 307 * each byte 1 except the last one which is 0.
308 */ 308 */
309 len++; 309 len++;
310 if (d) *d++ = 0x1F | flags; 310 if (d) *d++ = 0x1F | flags;
311 for (n = 1; (id >> (7*n)) > 0; n++) 311 for (n = 1; (id >> (7*n)) > 0; n++)
312 continue; /* count the bytes */ 312 continue; /* count the bytes */
313 while (n--) { 313 while (n--) {
314 len++; 314 len++;
315 if (d) *d++ = (n ? 0x80 : 0) | ((id >> (7*n)) & 0x7F); 315 if (d) *d++ = (n ? 0x80 : 0) | ((id >> (7*n)) & 0x7F);
316 } 316 }
317 } 317 }
318 318
319 if (length < 128) { 319 if (length < 128) {
320 /* 320 /*
321 * Length is one byte. 321 * Length is one byte.
322 */ 322 */
323 len++; 323 len++;
324 if (d) *d++ = length; 324 if (d) *d++ = length;
325 } else { 325 } else {
326 int n; 326 int n;
327 /* 327 /*
328 * Length is multiple bytes. The first is 0x80 plus the 328 * Length is multiple bytes. The first is 0x80 plus the
329 * number of subsequent bytes, and the subsequent bytes 329 * number of subsequent bytes, and the subsequent bytes
330 * encode the actual length. 330 * encode the actual length.
331 */ 331 */
332 for (n = 1; (length >> (8*n)) > 0; n++) 332 for (n = 1; (length >> (8*n)) > 0; n++)
333 continue; /* count the bytes */ 333 continue; /* count the bytes */
334 len++; 334 len++;
335 if (d) *d++ = 0x80 | n; 335 if (d) *d++ = 0x80 | n;
336 while (n--) { 336 while (n--) {
337 len++; 337 len++;
338 if (d) *d++ = (length >> (8*n)) & 0xFF; 338 if (d) *d++ = (length >> (8*n)) & 0xFF;
339 } 339 }
340 } 340 }
341 341
342 return len; 342 return len;
343 } 343 }
344 344
345 345
346 /* Simple structure to point to an mp-int within a blob. */ 346 /* Simple structure to point to an mp-int within a blob. */
347 struct mpint_pos { void *start; int bytes; }; 347 struct mpint_pos { void *start; int bytes; };
350 * Code to read and write OpenSSH private keys. 350 * Code to read and write OpenSSH private keys.
351 */ 351 */
352 352
353 enum { OSSH_DSA, OSSH_RSA, OSSH_EC }; 353 enum { OSSH_DSA, OSSH_RSA, OSSH_EC };
354 struct openssh_key { 354 struct openssh_key {
355 int type; 355 int type;
356 int encrypted; 356 int encrypted;
357 char iv[32]; 357 char iv[32];
358 unsigned char *keyblob; 358 unsigned char *keyblob;
359 unsigned int keyblob_len, keyblob_size; 359 unsigned int keyblob_len, keyblob_size;
360 }; 360 };
361 361
362 static struct openssh_key *load_openssh_key(const char *filename) 362 static struct openssh_key *load_openssh_key(const char *filename)
363 { 363 {
364 struct openssh_key *ret; 364 struct openssh_key *ret;
365 FILE *fp = NULL; 365 FILE *fp = NULL;
366 char buffer[256]; 366 char buffer[256];
367 char *errmsg = NULL, *p = NULL; 367 char *errmsg = NULL, *p = NULL;
368 int headers_done; 368 int headers_done;
369 unsigned long len, outlen; 369 unsigned long len, outlen;
370 370
371 ret = (struct openssh_key*)m_malloc(sizeof(struct openssh_key)); 371 ret = (struct openssh_key*)m_malloc(sizeof(struct openssh_key));
372 ret->keyblob = NULL; 372 ret->keyblob = NULL;
373 ret->keyblob_len = ret->keyblob_size = 0; 373 ret->keyblob_len = ret->keyblob_size = 0;
374 ret->encrypted = 0; 374 ret->encrypted = 0;
375 memset(ret->iv, 0, sizeof(ret->iv)); 375 memset(ret->iv, 0, sizeof(ret->iv));
376 376
377 if (strlen(filename) == 1 && filename[0] == '-') { 377 if (strlen(filename) == 1 && filename[0] == '-') {
378 fp = stdin; 378 fp = stdin;
379 } else { 379 } else {
380 fp = fopen(filename, "r"); 380 fp = fopen(filename, "r");
381 } 381 }
382 if (!fp) { 382 if (!fp) {
383 errmsg = "Unable to open key file"; 383 errmsg = "Unable to open key file";
384 goto error; 384 goto error;
385 } 385 }
386 if (!fgets(buffer, sizeof(buffer), fp) || 386 if (!fgets(buffer, sizeof(buffer), fp) ||
387 0 != strncmp(buffer, "-----BEGIN ", 11) || 387 0 != strncmp(buffer, "-----BEGIN ", 11) ||
388 0 != strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) { 388 0 != strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) {
389 errmsg = "File does not begin with OpenSSH key header"; 389 errmsg = "File does not begin with OpenSSH key header";
390 goto error; 390 goto error;
391 } 391 }
392 if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n")) 392 if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n"))
393 ret->type = OSSH_RSA; 393 ret->type = OSSH_RSA;
394 else if (!strcmp(buffer, "-----BEGIN DSA PRIVATE KEY-----\n")) 394 else if (!strcmp(buffer, "-----BEGIN DSA PRIVATE KEY-----\n"))
395 ret->type = OSSH_DSA; 395 ret->type = OSSH_DSA;
396 else if (!strcmp(buffer, "-----BEGIN EC PRIVATE KEY-----\n")) 396 else if (!strcmp(buffer, "-----BEGIN EC PRIVATE KEY-----\n"))
397 ret->type = OSSH_EC; 397 ret->type = OSSH_EC;
398 else { 398 else {
399 errmsg = "Unrecognised key type"; 399 errmsg = "Unrecognised key type";
400 goto error; 400 goto error;
401 } 401 }
402 402
403 headers_done = 0; 403 headers_done = 0;
404 while (1) { 404 while (1) {
405 if (!fgets(buffer, sizeof(buffer), fp)) { 405 if (!fgets(buffer, sizeof(buffer), fp)) {
406 errmsg = "Unexpected end of file"; 406 errmsg = "Unexpected end of file";
407 goto error; 407 goto error;
408 } 408 }
409 if (0 == strncmp(buffer, "-----END ", 9) && 409 if (0 == strncmp(buffer, "-----END ", 9) &&
410 0 == strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) 410 0 == strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n"))
411 break; /* done */ 411 break; /* done */
412 if ((p = strchr(buffer, ':')) != NULL) { 412 if ((p = strchr(buffer, ':')) != NULL) {
413 if (headers_done) { 413 if (headers_done) {
414 errmsg = "Header found in body of key data"; 414 errmsg = "Header found in body of key data";
415 goto error; 415 goto error;
416 }
417 *p++ = '\0';
418 while (*p && isspace((unsigned char)*p)) p++;
419 if (!strcmp(buffer, "Proc-Type")) {
420 if (p[0] != '4' || p[1] != ',') {
421 errmsg = "Proc-Type is not 4 (only 4 is supported)";
422 goto error;
423 }
424 p += 2;
425 if (!strcmp(p, "ENCRYPTED\n"))
426 ret->encrypted = 1;
427 } else if (!strcmp(buffer, "DEK-Info")) {
428 int i, j;
429
430 if (strncmp(p, "DES-EDE3-CBC,", 13)) {
431 errmsg = "Ciphers other than DES-EDE3-CBC not supported";
432 goto error;
433 }
434 p += 13;
435 for (i = 0; i < 8; i++) {
436 if (1 != sscanf(p, "%2x", &j))
437 break;
438 ret->iv[i] = j;
439 p += 2;
440 }
441 if (i < 8) {
442 errmsg = "Expected 16-digit iv in DEK-Info";
443 goto error;
444 }
445 }
446 } else {
447 headers_done = 1;
448 len = strlen(buffer);
449 outlen = len*4/3;
450 if (ret->keyblob_len + outlen > ret->keyblob_size) {
451 ret->keyblob_size = ret->keyblob_len + outlen + 256;
452 ret->keyblob = (unsigned char*)m_realloc(ret->keyblob,
453 ret->keyblob_size);
454 } 416 }
455 outlen = ret->keyblob_size - ret->keyblob_len; 417 *p++ = '\0';
456 if (base64_decode((const unsigned char *)buffer, len, 418 while (*p && isspace((unsigned char)*p)) p++;
457 ret->keyblob + ret->keyblob_len, &outlen) != CRYPT_OK){ 419 if (!strcmp(buffer, "Proc-Type")) {
458 errmsg = "Error decoding base64"; 420 if (p[0] != '4' || p[1] != ',') {
459 goto error; 421 errmsg = "Proc-Type is not 4 (only 4 is supported)";
460 } 422 goto error;
461 ret->keyblob_len += outlen; 423 }
462 } 424 p += 2;
463 } 425 if (!strcmp(p, "ENCRYPTED\n"))
464 426 ret->encrypted = 1;
465 if (ret->keyblob_len == 0 || !ret->keyblob) { 427 } else if (!strcmp(buffer, "DEK-Info")) {
466 errmsg = "Key body not present"; 428 int i, j;
467 goto error; 429
468 } 430 if (strncmp(p, "DES-EDE3-CBC,", 13)) {
469 431 errmsg = "Ciphers other than DES-EDE3-CBC not supported";
470 if (ret->encrypted && ret->keyblob_len % 8 != 0) { 432 goto error;
471 errmsg = "Encrypted key blob is not a multiple of cipher block size"; 433 }
472 goto error; 434 p += 13;
473 } 435 for (i = 0; i < 8; i++) {
436 if (1 != sscanf(p, "%2x", &j))
437 break;
438 ret->iv[i] = j;
439 p += 2;
440 }
441 if (i < 8) {
442 errmsg = "Expected 16-digit iv in DEK-Info";
443 goto error;
444 }
445 }
446 } else {
447 headers_done = 1;
448 len = strlen(buffer);
449 outlen = len*4/3;
450 if (ret->keyblob_len + outlen > ret->keyblob_size) {
451 ret->keyblob_size = ret->keyblob_len + outlen + 256;
452 ret->keyblob = (unsigned char*)m_realloc(ret->keyblob,
453 ret->keyblob_size);
454 }
455 outlen = ret->keyblob_size - ret->keyblob_len;
456 if (base64_decode((const unsigned char *)buffer, len,
457 ret->keyblob + ret->keyblob_len, &outlen) != CRYPT_OK){
458 errmsg = "Error decoding base64";
459 goto error;
460 }
461 ret->keyblob_len += outlen;
462 }
463 }
464
465 if (ret->keyblob_len == 0 || !ret->keyblob) {
466 errmsg = "Key body not present";
467 goto error;
468 }
469
470 if (ret->encrypted && ret->keyblob_len % 8 != 0) {
471 errmsg = "Encrypted key blob is not a multiple of cipher block size";
472 goto error;
473 }
474 474
475 m_burn(buffer, sizeof(buffer)); 475 m_burn(buffer, sizeof(buffer));
476 return ret; 476 return ret;
477 477
478 error: 478 error:
479 m_burn(buffer, sizeof(buffer)); 479 m_burn(buffer, sizeof(buffer));
480 if (ret) { 480 if (ret) {
481 if (ret->keyblob) { 481 if (ret->keyblob) {
482 m_burn(ret->keyblob, ret->keyblob_size); 482 m_burn(ret->keyblob, ret->keyblob_size);
483 m_free(ret->keyblob); 483 m_free(ret->keyblob);
484 } 484 }
485 m_free(ret); 485 m_free(ret);
486 } 486 }
487 if (fp) { 487 if (fp) {
488 fclose(fp); 488 fclose(fp);
489 } 489 }
490 if (errmsg) { 490 if (errmsg) {
491 fprintf(stderr, "Error: %s\n", errmsg); 491 fprintf(stderr, "Error: %s\n", errmsg);
492 } 492 }
493 return NULL; 493 return NULL;
494 } 494 }
495 495
496 static int openssh_encrypted(const char *filename) 496 static int openssh_encrypted(const char *filename)
497 { 497 {
498 struct openssh_key *key = load_openssh_key(filename); 498 struct openssh_key *key = load_openssh_key(filename);
499 int ret; 499 int ret;
500 500
501 if (!key) 501 if (!key)
502 return 0; 502 return 0;
503 ret = key->encrypted; 503 ret = key->encrypted;
504 m_burn(key->keyblob, key->keyblob_size); 504 m_burn(key->keyblob, key->keyblob_size);
505 m_free(key->keyblob); 505 m_free(key->keyblob);
506 m_free(key); 506 m_free(key);
507 return ret; 507 return ret;
508 } 508 }
509 509
510 static sign_key *openssh_read(const char *filename, char * UNUSED(passphrase)) 510 static sign_key *openssh_read(const char *filename, char * UNUSED(passphrase))
511 { 511 {
512 struct openssh_key *key; 512 struct openssh_key *key;
513 unsigned char *p; 513 unsigned char *p;
514 int ret, id, len, flags; 514 int ret, id, len, flags;
515 int i, num_integers = 0; 515 int i, num_integers = 0;
516 sign_key *retval = NULL; 516 sign_key *retval = NULL;
517 char *errmsg; 517 char *errmsg;
518 unsigned char *modptr = NULL; 518 unsigned char *modptr = NULL;
519 int modlen = -9999; 519 int modlen = -9999;
520 enum signkey_type type; 520 enum signkey_type type;
521 521
522 sign_key *retkey; 522 sign_key *retkey;
523 buffer * blobbuf = NULL; 523 buffer * blobbuf = NULL;
524 524
525 retkey = new_sign_key(); 525 retkey = new_sign_key();
526 526
527 key = load_openssh_key(filename); 527 key = load_openssh_key(filename);
528 528
529 if (!key) 529 if (!key)
530 return NULL; 530 return NULL;
531 531
532 if (key->encrypted) { 532 if (key->encrypted) {
533 errmsg = "encrypted keys not supported currently"; 533 errmsg = "encrypted keys not supported currently";
534 goto error; 534 goto error;
535 #if 0 535 #if 0
536 /* matt TODO */ 536 /* matt TODO */
537 /* 537 /*
538 * Derive encryption key from passphrase and iv/salt: 538 * Derive encryption key from passphrase and iv/salt:
539 * 539 *
540 * - let block A equal MD5(passphrase || iv) 540 * - let block A equal MD5(passphrase || iv)
541 * - let block B equal MD5(A || passphrase || iv) 541 * - let block B equal MD5(A || passphrase || iv)
542 * - block C would be MD5(B || passphrase || iv) and so on 542 * - block C would be MD5(B || passphrase || iv) and so on
543 * - encryption key is the first N bytes of A || B 543 * - encryption key is the first N bytes of A || B
544 */ 544 */
545 struct MD5Context md5c; 545 struct MD5Context md5c;
546 unsigned char keybuf[32]; 546 unsigned char keybuf[32];
547 547
548 MD5Init(&md5c); 548 MD5Init(&md5c);
549 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); 549 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
550 MD5Update(&md5c, (unsigned char *)key->iv, 8); 550 MD5Update(&md5c, (unsigned char *)key->iv, 8);
551 MD5Final(keybuf, &md5c); 551 MD5Final(keybuf, &md5c);
552 552
553 MD5Init(&md5c); 553 MD5Init(&md5c);
554 MD5Update(&md5c, keybuf, 16); 554 MD5Update(&md5c, keybuf, 16);
555 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); 555 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
556 MD5Update(&md5c, (unsigned char *)key->iv, 8); 556 MD5Update(&md5c, (unsigned char *)key->iv, 8);
557 MD5Final(keybuf+16, &md5c); 557 MD5Final(keybuf+16, &md5c);
558 558
559 /* 559 /*
560 * Now decrypt the key blob. 560 * Now decrypt the key blob.
561 */ 561 */
562 des3_decrypt_pubkey_ossh(keybuf, (unsigned char *)key->iv, 562 des3_decrypt_pubkey_ossh(keybuf, (unsigned char *)key->iv,
563 key->keyblob, key->keyblob_len); 563 key->keyblob, key->keyblob_len);
564 564
565 memset(&md5c, 0, sizeof(md5c)); 565 memset(&md5c, 0, sizeof(md5c));
566 memset(keybuf, 0, sizeof(keybuf)); 566 memset(keybuf, 0, sizeof(keybuf));
567 #endif 567 #endif
568 } 568 }
569 569
570 /* 570 /*
571 * Now we have a decrypted key blob, which contains an ASN.1 571 * Now we have a decrypted key blob, which contains an ASN.1
572 * encoded private key. We must now untangle the ASN.1. 572 * encoded private key. We must now untangle the ASN.1.
573 * 573 *
574 * We expect the whole key blob to be formatted as a SEQUENCE 574 * We expect the whole key blob to be formatted as a SEQUENCE
575 * (0x30 followed by a length code indicating that the rest of 575 * (0x30 followed by a length code indicating that the rest of
576 * the blob is part of the sequence). Within that SEQUENCE we 576 * the blob is part of the sequence). Within that SEQUENCE we
577 * expect to see a bunch of INTEGERs. What those integers mean 577 * expect to see a bunch of INTEGERs. What those integers mean
578 * depends on the key type: 578 * depends on the key type:
579 * 579 *
580 * - For RSA, we expect the integers to be 0, n, e, d, p, q, 580 * - For RSA, we expect the integers to be 0, n, e, d, p, q,
581 * dmp1, dmq1, iqmp in that order. (The last three are d mod 581 * dmp1, dmq1, iqmp in that order. (The last three are d mod
582 * (p-1), d mod (q-1), inverse of q mod p respectively.) 582 * (p-1), d mod (q-1), inverse of q mod p respectively.)
583 * 583 *
584 * - For DSA, we expect them to be 0, p, q, g, y, x in that 584 * - For DSA, we expect them to be 0, p, q, g, y, x in that
585 * order. 585 * order.
586 */ 586 */
587 587
588 p = key->keyblob; 588 p = key->keyblob;
589 589
590 /* Expect the SEQUENCE header. Take its absence as a failure to decrypt. */ 590 /* Expect the SEQUENCE header. Take its absence as a failure to decrypt. */
591 ret = ber_read_id_len(p, key->keyblob_len, &id, &len, &flags); 591 ret = ber_read_id_len(p, key->keyblob_len, &id, &len, &flags);
592 p += ret; 592 p += ret;
593 if (ret < 0 || id != 16 || len < 0 || 593 if (ret < 0 || id != 16 || len < 0 ||
594 key->keyblob+key->keyblob_len-p < len) { 594 key->keyblob+key->keyblob_len-p < len) {
595 errmsg = "ASN.1 decoding failure"; 595 errmsg = "ASN.1 decoding failure";
596 goto error; 596 goto error;
597 } 597 }
598 598
599 /* Expect a load of INTEGERs. */ 599 /* Expect a load of INTEGERs. */
600 if (key->type == OSSH_RSA) 600 if (key->type == OSSH_RSA)
601 num_integers = 9; 601 num_integers = 9;
602 else if (key->type == OSSH_DSA) 602 else if (key->type == OSSH_DSA)
603 num_integers = 6; 603 num_integers = 6;
604 else if (key->type == OSSH_EC) 604 else if (key->type == OSSH_EC)
605 num_integers = 1; 605 num_integers = 1;
606 606
607 /* 607 /*
608 * Space to create key blob in. 608 * Space to create key blob in.
609 */ 609 */
610 blobbuf = buf_new(3000); 610 blobbuf = buf_new(3000);
611 611
612 #ifdef DROPBEAR_DSS 612 #ifdef DROPBEAR_DSS
613 if (key->type == OSSH_DSA) { 613 if (key->type == OSSH_DSA) {
614 buf_putstring(blobbuf, "ssh-dss", 7); 614 buf_putstring(blobbuf, "ssh-dss", 7);
615 retkey->type = DROPBEAR_SIGNKEY_DSS; 615 retkey->type = DROPBEAR_SIGNKEY_DSS;
616 } 616 }
617 #endif 617 #endif
618 #ifdef DROPBEAR_RSA 618 #ifdef DROPBEAR_RSA
619 if (key->type == OSSH_RSA) { 619 if (key->type == OSSH_RSA) {
620 buf_putstring(blobbuf, "ssh-rsa", 7); 620 buf_putstring(blobbuf, "ssh-rsa", 7);
621 retkey->type = DROPBEAR_SIGNKEY_RSA; 621 retkey->type = DROPBEAR_SIGNKEY_RSA;
622 } 622 }
623 #endif 623 #endif
624 624
625 for (i = 0; i < num_integers; i++) { 625 for (i = 0; i < num_integers; i++) {
626 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
627 &id, &len, &flags);
628 p += ret;
629 if (ret < 0 || id != 2 || len < 0 ||
630 key->keyblob+key->keyblob_len-p < len) {
631 errmsg = "ASN.1 decoding failure";
632 goto error;
633 }
634
635 if (i == 0) {
636 /* First integer is a version indicator */
637 int expected = -1;
638 switch (key->type) {
639 case OSSH_RSA:
640 case OSSH_DSA:
641 expected = 0;
642 break;
643 case OSSH_EC:
644 expected = 1;
645 break;
646 }
647 if (len != 1 || p[0] != expected) {
648 errmsg = "Version number mismatch";
649 goto error;
650 }
651 } else if (key->type == OSSH_RSA) {
652 /*
653 * OpenSSH key order is n, e, d, p, q, dmp1, dmq1, iqmp
654 * but we want e, n, d, p, q
655 */
656 if (i == 1) {
657 /* Save the details for after we deal with number 2. */
658 modptr = p;
659 modlen = len;
660 } else if (i >= 2 && i <= 5) {
661 buf_putstring(blobbuf, (const char*)p, len);
662 if (i == 2) {
663 buf_putstring(blobbuf, (const char*)modptr, modlen);
664 }
665 }
666 } else if (key->type == OSSH_DSA) {
667 /*
668 * OpenSSH key order is p, q, g, y, x,
669 * we want the same.
670 */
671 buf_putstring(blobbuf, (const char*)p, len);
672 }
673
674 /* Skip past the number. */
675 p += len;
676 }
677
678 #ifdef DROPBEAR_ECDSA
679 if (key->type == OSSH_EC) {
680 unsigned char* private_key_bytes = NULL;
681 int private_key_len = 0;
682 unsigned char* public_key_bytes = NULL;
683 int public_key_len = 0;
684 ecc_key *ecc = NULL;
685 const struct dropbear_ecc_curve *curve = NULL;
686
687 /* See SEC1 v2, Appendix C.4 */
688 /* OpenSSL (so OpenSSH) seems to include the optional parts. */
689
690 /* privateKey OCTET STRING, */
691 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, 626 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
692 &id, &len, &flags); 627 &id, &len, &flags);
693 p += ret; 628 p += ret;
694 /* id==4 for octet string */ 629 if (ret < 0 || id != 2 || len < 0 ||
695 if (ret < 0 || id != 4 || len < 0 ||
696 key->keyblob+key->keyblob_len-p < len) { 630 key->keyblob+key->keyblob_len-p < len) {
697 errmsg = "ASN.1 decoding failure"; 631 errmsg = "ASN.1 decoding failure";
698 goto error; 632 goto error;
699 } 633 }
700 private_key_bytes = p; 634
701 private_key_len = len; 635 if (i == 0) {
636 /* First integer is a version indicator */
637 int expected = -1;
638 switch (key->type) {
639 case OSSH_RSA:
640 case OSSH_DSA:
641 expected = 0;
642 break;
643 case OSSH_EC:
644 expected = 1;
645 break;
646 }
647 if (len != 1 || p[0] != expected) {
648 errmsg = "Version number mismatch";
649 goto error;
650 }
651 } else if (key->type == OSSH_RSA) {
652 /*
653 * OpenSSH key order is n, e, d, p, q, dmp1, dmq1, iqmp
654 * but we want e, n, d, p, q
655 */
656 if (i == 1) {
657 /* Save the details for after we deal with number 2. */
658 modptr = p;
659 modlen = len;
660 } else if (i >= 2 && i <= 5) {
661 buf_putstring(blobbuf, (const char*)p, len);
662 if (i == 2) {
663 buf_putstring(blobbuf, (const char*)modptr, modlen);
664 }
665 }
666 } else if (key->type == OSSH_DSA) {
667 /*
668 * OpenSSH key order is p, q, g, y, x,
669 * we want the same.
670 */
671 buf_putstring(blobbuf, (const char*)p, len);
672 }
673
674 /* Skip past the number. */
702 p += len; 675 p += len;
703 676 }
704 /* parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL, */ 677
705 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, 678 #ifdef DROPBEAR_ECDSA
706 &id, &len, &flags); 679 if (key->type == OSSH_EC) {
707 p += ret; 680 unsigned char* private_key_bytes = NULL;
708 /* id==0 */ 681 int private_key_len = 0;
709 if (ret < 0 || id != 0 || len < 0) { 682 unsigned char* public_key_bytes = NULL;
710 errmsg = "ASN.1 decoding failure"; 683 int public_key_len = 0;
711 goto error; 684 ecc_key *ecc = NULL;
712 } 685 const struct dropbear_ecc_curve *curve = NULL;
713 686
714 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, 687 /* See SEC1 v2, Appendix C.4 */
715 &id, &len, &flags); 688 /* OpenSSL (so OpenSSH) seems to include the optional parts. */
716 p += ret; 689
717 /* id==6 for object */ 690 /* privateKey OCTET STRING, */
718 if (ret < 0 || id != 6 || len < 0 || 691 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
719 key->keyblob+key->keyblob_len-p < len) { 692 &id, &len, &flags);
720 errmsg = "ASN.1 decoding failure"; 693 p += ret;
721 goto error; 694 /* id==4 for octet string */
722 } 695 if (ret < 0 || id != 4 || len < 0 ||
723 696 key->keyblob+key->keyblob_len-p < len) {
724 if (0) {} 697 errmsg = "ASN.1 decoding failure";
698 goto error;
699 }
700 private_key_bytes = p;
701 private_key_len = len;
702 p += len;
703
704 /* parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL, */
705 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
706 &id, &len, &flags);
707 p += ret;
708 /* id==0 */
709 if (ret < 0 || id != 0 || len < 0) {
710 errmsg = "ASN.1 decoding failure";
711 goto error;
712 }
713
714 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
715 &id, &len, &flags);
716 p += ret;
717 /* id==6 for object */
718 if (ret < 0 || id != 6 || len < 0 ||
719 key->keyblob+key->keyblob_len-p < len) {
720 errmsg = "ASN.1 decoding failure";
721 goto error;
722 }
723
724 if (0) {}
725 #ifdef DROPBEAR_ECC_256 725 #ifdef DROPBEAR_ECC_256
726 else if (len == sizeof(OID_SEC256R1_BLOB) 726 else if (len == sizeof(OID_SEC256R1_BLOB)
727 && memcmp(p, OID_SEC256R1_BLOB, len) == 0) { 727 && memcmp(p, OID_SEC256R1_BLOB, len) == 0) {
728 retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP256; 728 retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP256;
729 curve = &ecc_curve_nistp256; 729 curve = &ecc_curve_nistp256;
730 } 730 }
731 #endif 731 #endif
732 #ifdef DROPBEAR_ECC_384 732 #ifdef DROPBEAR_ECC_384
733 else if (len == sizeof(OID_SEC384R1_BLOB) 733 else if (len == sizeof(OID_SEC384R1_BLOB)
734 && memcmp(p, OID_SEC384R1_BLOB, len) == 0) { 734 && memcmp(p, OID_SEC384R1_BLOB, len) == 0) {
735 retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP384; 735 retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP384;
736 curve = &ecc_curve_nistp384; 736 curve = &ecc_curve_nistp384;
737 } 737 }
738 #endif 738 #endif
739 #ifdef DROPBEAR_ECC_521 739 #ifdef DROPBEAR_ECC_521
740 else if (len == sizeof(OID_SEC521R1_BLOB) 740 else if (len == sizeof(OID_SEC521R1_BLOB)
741 && memcmp(p, OID_SEC521R1_BLOB, len) == 0) { 741 && memcmp(p, OID_SEC521R1_BLOB, len) == 0) {
742 retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP521; 742 retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP521;
743 curve = &ecc_curve_nistp521; 743 curve = &ecc_curve_nistp521;
744 } 744 }
745 #endif 745 #endif
746 else { 746 else {
747 errmsg = "Unknown ECC key type"; 747 errmsg = "Unknown ECC key type";
748 goto error; 748 goto error;
749 } 749 }
750 p += len; 750 p += len;
751 751
752 /* publicKey [1] BIT STRING OPTIONAL */ 752 /* publicKey [1] BIT STRING OPTIONAL */
753 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, 753 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
754 &id, &len, &flags); 754 &id, &len, &flags);
755 p += ret; 755 p += ret;
756 /* id==1 */ 756 /* id==1 */
757 if (ret < 0 || id != 1 || len < 0) { 757 if (ret < 0 || id != 1 || len < 0) {
758 errmsg = "ASN.1 decoding failure"; 758 errmsg = "ASN.1 decoding failure";
759 goto error; 759 goto error;
760 } 760 }
761 761
762 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, 762 ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
763 &id, &len, &flags); 763 &id, &len, &flags);
764 p += ret; 764 p += ret;
765 /* id==3 for bit string */ 765 /* id==3 for bit string */
766 if (ret < 0 || id != 3 || len < 0 || 766 if (ret < 0 || id != 3 || len < 0 ||
767 key->keyblob+key->keyblob_len-p < len) { 767 key->keyblob+key->keyblob_len-p < len) {
768 errmsg = "ASN.1 decoding failure"; 768 errmsg = "ASN.1 decoding failure";
769 goto error; 769 goto error;
770 } 770 }
771 public_key_bytes = p+1; 771 public_key_bytes = p+1;
772 public_key_len = len-1; 772 public_key_len = len-1;
773 p += len; 773 p += len;
774 774
775 buf_putbytes(blobbuf, public_key_bytes, public_key_len); 775 buf_putbytes(blobbuf, public_key_bytes, public_key_len);
776 ecc = buf_get_ecc_raw_pubkey(blobbuf, curve); 776 ecc = buf_get_ecc_raw_pubkey(blobbuf, curve);
777 if (!ecc) { 777 if (!ecc) {
778 errmsg = "Error parsing ECC key"; 778 errmsg = "Error parsing ECC key";
779 goto error; 779 goto error;
780 } 780 }
781 m_mp_alloc_init_multi((mp_int**)&ecc->k, NULL); 781 m_mp_alloc_init_multi((mp_int**)&ecc->k, NULL);
782 if (mp_read_unsigned_bin(ecc->k, private_key_bytes, private_key_len) 782 if (mp_read_unsigned_bin(ecc->k, private_key_bytes, private_key_len)
783 != MP_OKAY) { 783 != MP_OKAY) {
784 errmsg = "Error parsing ECC key"; 784 errmsg = "Error parsing ECC key";
785 goto error; 785 goto error;
786 } 786 }
787 787
788 *signkey_key_ptr(retkey, retkey->type) = ecc; 788 *signkey_key_ptr(retkey, retkey->type) = ecc;
789 } 789 }
790 #endif /* DROPBEAR_ECDSA */ 790 #endif /* DROPBEAR_ECDSA */
791 791
792 /* 792 /*
793 * Now put together the actual key. Simplest way to do this is 793 * Now put together the actual key. Simplest way to do this is
794 * to assemble our own key blobs and feed them to the createkey 794 * to assemble our own key blobs and feed them to the createkey
795 * functions; this is a bit faffy but it does mean we get all 795 * functions; this is a bit faffy but it does mean we get all
796 * the sanity checks for free. 796 * the sanity checks for free.
797 */ 797 */
798 if (key->type == OSSH_RSA || key->type == OSSH_DSA) { 798 if (key->type == OSSH_RSA || key->type == OSSH_DSA) {
799 buf_setpos(blobbuf, 0); 799 buf_setpos(blobbuf, 0);
800 type = DROPBEAR_SIGNKEY_ANY; 800 type = DROPBEAR_SIGNKEY_ANY;
801 if (buf_get_priv_key(blobbuf, retkey, &type) 801 if (buf_get_priv_key(blobbuf, retkey, &type)
802 != DROPBEAR_SUCCESS) { 802 != DROPBEAR_SUCCESS) {
803 errmsg = "unable to create key structure"; 803 errmsg = "unable to create key structure";
804 sign_key_free(retkey); 804 sign_key_free(retkey);
805 retkey = NULL; 805 retkey = NULL;
806 goto error; 806 goto error;
807 } 807 }
808 } 808 }
809 809
810 errmsg = NULL; /* no error */ 810 errmsg = NULL; /* no error */
811 retval = retkey; 811 retval = retkey;
812 812
813 error: 813 error:
814 if (blobbuf) { 814 if (blobbuf) {
815 buf_burn(blobbuf); 815 buf_burn(blobbuf);
816 buf_free(blobbuf); 816 buf_free(blobbuf);
817 } 817 }
818 m_burn(key->keyblob, key->keyblob_size); 818 m_burn(key->keyblob, key->keyblob_size);
819 m_free(key->keyblob); 819 m_free(key->keyblob);
820 m_burn(key, sizeof(*key)); 820 m_burn(key, sizeof(*key));
821 m_free(key); 821 m_free(key);
822 if (errmsg) { 822 if (errmsg) {
823 fprintf(stderr, "Error: %s\n", errmsg); 823 fprintf(stderr, "Error: %s\n", errmsg);
824 } 824 }
825 return retval; 825 return retval;
826 } 826 }
827 827
828 static int openssh_write(const char *filename, sign_key *key, 828 static int openssh_write(const char *filename, sign_key *key,
829 char *passphrase) 829 char *passphrase)
830 { 830 {
831 buffer * keyblob = NULL; 831 buffer * keyblob = NULL;
832 buffer * extrablob = NULL; /* used for calculated values to write */ 832 buffer * extrablob = NULL; /* used for calculated values to write */
833 unsigned char *outblob = NULL; 833 unsigned char *outblob = NULL;
834 int outlen = -9999; 834 int outlen = -9999;
835 struct mpint_pos numbers[9]; 835 struct mpint_pos numbers[9];
836 int nnumbers = -1, pos = 0, len = 0, seqlen, i; 836 int nnumbers = -1, pos = 0, len = 0, seqlen, i;
837 char *header = NULL, *footer = NULL; 837 char *header = NULL, *footer = NULL;
838 char zero[1]; 838 char zero[1];
839 int ret = 0; 839 int ret = 0;
840 FILE *fp; 840 FILE *fp;
841 841
842 #ifdef DROPBEAR_RSA 842 #ifdef DROPBEAR_RSA
843 mp_int dmp1, dmq1, iqmp, tmpval; /* for rsa */ 843 mp_int dmp1, dmq1, iqmp, tmpval; /* for rsa */
844 #endif 844 #endif
845 845
846 if ( 846 if (
847 #ifdef DROPBEAR_RSA 847 #ifdef DROPBEAR_RSA
848 key->type == DROPBEAR_SIGNKEY_RSA || 848 key->type == DROPBEAR_SIGNKEY_RSA ||
849 #endif 849 #endif
850 #ifdef DROPBEAR_DSS 850 #ifdef DROPBEAR_DSS
851 key->type == DROPBEAR_SIGNKEY_DSS || 851 key->type == DROPBEAR_SIGNKEY_DSS ||
852 #endif 852 #endif
853 0) 853 0)
854 { 854 {
855 /* 855 /*
856 * Fetch the key blobs. 856 * Fetch the key blobs.
857 */ 857 */
858 keyblob = buf_new(3000); 858 keyblob = buf_new(3000);
859 buf_put_priv_key(keyblob, key, key->type); 859 buf_put_priv_key(keyblob, key, key->type);
860 860
861 buf_setpos(keyblob, 0); 861 buf_setpos(keyblob, 0);
862 /* skip the "ssh-rsa" or "ssh-dss" header */ 862 /* skip the "ssh-rsa" or "ssh-dss" header */
863 buf_incrpos(keyblob, buf_getint(keyblob)); 863 buf_incrpos(keyblob, buf_getint(keyblob));
864 864
865 /* 865 /*
866 * Find the sequence of integers to be encoded into the OpenSSH 866 * Find the sequence of integers to be encoded into the OpenSSH
867 * key blob, and also decide on the header line. 867 * key blob, and also decide on the header line.
868 */ 868 */
869 numbers[0].start = zero; numbers[0].bytes = 1; zero[0] = '\0'; 869 numbers[0].start = zero; numbers[0].bytes = 1; zero[0] = '\0';
870 870
871 #ifdef DROPBEAR_RSA 871 #ifdef DROPBEAR_RSA
872 if (key->type == DROPBEAR_SIGNKEY_RSA) { 872 if (key->type == DROPBEAR_SIGNKEY_RSA) {
873 873
874 if (key->rsakey->p == NULL || key->rsakey->q == NULL) { 874 if (key->rsakey->p == NULL || key->rsakey->q == NULL) {
875 fprintf(stderr, "Pre-0.33 Dropbear keys cannot be converted to OpenSSH keys.\n"); 875 fprintf(stderr, "Pre-0.33 Dropbear keys cannot be converted to OpenSSH keys.\n");
876 goto error;
877 }
878
879 /* e */
880 numbers[2].bytes = buf_getint(keyblob);
881 numbers[2].start = buf_getptr(keyblob, numbers[2].bytes);
882 buf_incrpos(keyblob, numbers[2].bytes);
883
884 /* n */
885 numbers[1].bytes = buf_getint(keyblob);
886 numbers[1].start = buf_getptr(keyblob, numbers[1].bytes);
887 buf_incrpos(keyblob, numbers[1].bytes);
888
889 /* d */
890 numbers[3].bytes = buf_getint(keyblob);
891 numbers[3].start = buf_getptr(keyblob, numbers[3].bytes);
892 buf_incrpos(keyblob, numbers[3].bytes);
893
894 /* p */
895 numbers[4].bytes = buf_getint(keyblob);
896 numbers[4].start = buf_getptr(keyblob, numbers[4].bytes);
897 buf_incrpos(keyblob, numbers[4].bytes);
898
899 /* q */
900 numbers[5].bytes = buf_getint(keyblob);
901 numbers[5].start = buf_getptr(keyblob, numbers[5].bytes);
902 buf_incrpos(keyblob, numbers[5].bytes);
903
904 /* now calculate some extra parameters: */
905 m_mp_init(&tmpval);
906 m_mp_init(&dmp1);
907 m_mp_init(&dmq1);
908 m_mp_init(&iqmp);
909
910 /* dmp1 = d mod (p-1) */
911 if (mp_sub_d(key->rsakey->p, 1, &tmpval) != MP_OKAY) {
912 fprintf(stderr, "Bignum error for p-1\n");
913 goto error;
914 }
915 if (mp_mod(key->rsakey->d, &tmpval, &dmp1) != MP_OKAY) {
916 fprintf(stderr, "Bignum error for dmp1\n");
917 goto error;
918 }
919
920 /* dmq1 = d mod (q-1) */
921 if (mp_sub_d(key->rsakey->q, 1, &tmpval) != MP_OKAY) {
922 fprintf(stderr, "Bignum error for q-1\n");
923 goto error;
924 }
925 if (mp_mod(key->rsakey->d, &tmpval, &dmq1) != MP_OKAY) {
926 fprintf(stderr, "Bignum error for dmq1\n");
927 goto error;
928 }
929
930 /* iqmp = (q^-1) mod p */
931 if (mp_invmod(key->rsakey->q, key->rsakey->p, &iqmp) != MP_OKAY) {
932 fprintf(stderr, "Bignum error for iqmp\n");
933 goto error;
934 }
935
936 extrablob = buf_new(2000);
937 buf_putmpint(extrablob, &dmp1);
938 buf_putmpint(extrablob, &dmq1);
939 buf_putmpint(extrablob, &iqmp);
940 buf_setpos(extrablob, 0);
941 mp_clear(&dmp1);
942 mp_clear(&dmq1);
943 mp_clear(&iqmp);
944 mp_clear(&tmpval);
945
946 /* dmp1 */
947 numbers[6].bytes = buf_getint(extrablob);
948 numbers[6].start = buf_getptr(extrablob, numbers[6].bytes);
949 buf_incrpos(extrablob, numbers[6].bytes);
950
951 /* dmq1 */
952 numbers[7].bytes = buf_getint(extrablob);
953 numbers[7].start = buf_getptr(extrablob, numbers[7].bytes);
954 buf_incrpos(extrablob, numbers[7].bytes);
955
956 /* iqmp */
957 numbers[8].bytes = buf_getint(extrablob);
958 numbers[8].start = buf_getptr(extrablob, numbers[8].bytes);
959 buf_incrpos(extrablob, numbers[8].bytes);
960
961 nnumbers = 9;
962 header = "-----BEGIN RSA PRIVATE KEY-----\n";
963 footer = "-----END RSA PRIVATE KEY-----\n";
964 }
965 #endif /* DROPBEAR_RSA */
966
967 #ifdef DROPBEAR_DSS
968 if (key->type == DROPBEAR_SIGNKEY_DSS) {
969
970 /* p */
971 numbers[1].bytes = buf_getint(keyblob);
972 numbers[1].start = buf_getptr(keyblob, numbers[1].bytes);
973 buf_incrpos(keyblob, numbers[1].bytes);
974
975 /* q */
976 numbers[2].bytes = buf_getint(keyblob);
977 numbers[2].start = buf_getptr(keyblob, numbers[2].bytes);
978 buf_incrpos(keyblob, numbers[2].bytes);
979
980 /* g */
981 numbers[3].bytes = buf_getint(keyblob);
982 numbers[3].start = buf_getptr(keyblob, numbers[3].bytes);
983 buf_incrpos(keyblob, numbers[3].bytes);
984
985 /* y */
986 numbers[4].bytes = buf_getint(keyblob);
987 numbers[4].start = buf_getptr(keyblob, numbers[4].bytes);
988 buf_incrpos(keyblob, numbers[4].bytes);
989
990 /* x */
991 numbers[5].bytes = buf_getint(keyblob);
992 numbers[5].start = buf_getptr(keyblob, numbers[5].bytes);
993 buf_incrpos(keyblob, numbers[5].bytes);
994
995 nnumbers = 6;
996 header = "-----BEGIN DSA PRIVATE KEY-----\n";
997 footer = "-----END DSA PRIVATE KEY-----\n";
998 }
999 #endif /* DROPBEAR_DSS */
1000
1001 /*
1002 * Now count up the total size of the ASN.1 encoded integers,
1003 * so as to determine the length of the containing SEQUENCE.
1004 */
1005 len = 0;
1006 for (i = 0; i < nnumbers; i++) {
1007 len += ber_write_id_len(NULL, 2, numbers[i].bytes, 0);
1008 len += numbers[i].bytes;
1009 }
1010 seqlen = len;
1011 /* Now add on the SEQUENCE header. */
1012 len += ber_write_id_len(NULL, 16, seqlen, ASN1_CONSTRUCTED);
1013 /* Round up to the cipher block size, ensuring we have at least one
1014 * byte of padding (see below). */
1015 outlen = len;
1016 if (passphrase)
1017 outlen = (outlen+8) &~ 7;
1018
1019 /*
1020 * Now we know how big outblob needs to be. Allocate it.
1021 */
1022 outblob = (unsigned char*)m_malloc(outlen);
1023
1024 /*
1025 * And write the data into it.
1026 */
1027 pos = 0;
1028 pos += ber_write_id_len(outblob+pos, 16, seqlen, ASN1_CONSTRUCTED);
1029 for (i = 0; i < nnumbers; i++) {
1030 pos += ber_write_id_len(outblob+pos, 2, numbers[i].bytes, 0);
1031 memcpy(outblob+pos, numbers[i].start, numbers[i].bytes);
1032 pos += numbers[i].bytes;
1033 }
1034 } /* end RSA and DSS handling */
1035
1036 #ifdef DROPBEAR_ECDSA
1037 if (key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP256
1038 || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP384
1039 || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP521) {
1040
1041 /* SEC1 V2 appendix c.4
1042 ECPrivateKey ::= SEQUENCE {
1043 version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
1044 privateKey OCTET STRING,
1045 parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL,
1046 publicKey [1] BIT STRING OPTIONAL
1047 }
1048 */
1049 buffer *seq_buf = buf_new(400);
1050 ecc_key **eck = (ecc_key**)signkey_key_ptr(key, key->type);
1051 const long curve_size = (*eck)->dp->size;
1052 int curve_oid_len = 0;
1053 const void* curve_oid = NULL;
1054 unsigned long pubkey_size = 2*curve_size+1;
1055 int k_size;
1056 int err = 0;
1057
1058 /* version. less than 10 bytes */
1059 buf_incrwritepos(seq_buf,
1060 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 2, 1, 0));
1061 buf_putbyte(seq_buf, 1);
1062
1063 /* privateKey */
1064 k_size = mp_unsigned_bin_size((*eck)->k);
1065 dropbear_assert(k_size <= curve_size);
1066 buf_incrwritepos(seq_buf,
1067 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 4, k_size, 0));
1068 mp_to_unsigned_bin((*eck)->k, buf_getwriteptr(seq_buf, k_size));
1069 buf_incrwritepos(seq_buf, k_size);
1070
1071 /* SECGCurveNames */
1072 switch (key->type)
1073 {
1074 case DROPBEAR_SIGNKEY_ECDSA_NISTP256:
1075 curve_oid_len = sizeof(OID_SEC256R1_BLOB);
1076 curve_oid = OID_SEC256R1_BLOB;
1077 break;
1078 case DROPBEAR_SIGNKEY_ECDSA_NISTP384:
1079 curve_oid_len = sizeof(OID_SEC384R1_BLOB);
1080 curve_oid = OID_SEC384R1_BLOB;
1081 break;
1082 case DROPBEAR_SIGNKEY_ECDSA_NISTP521:
1083 curve_oid_len = sizeof(OID_SEC521R1_BLOB);
1084 curve_oid = OID_SEC521R1_BLOB;
1085 break;
1086 default:
1087 dropbear_exit("Internal error");
1088 }
1089
1090 buf_incrwritepos(seq_buf,
1091 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 0, 2+curve_oid_len, 0xa0));
1092 /* object == 6 */
1093 buf_incrwritepos(seq_buf,
1094 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 6, curve_oid_len, 0));
1095 buf_putbytes(seq_buf, curve_oid, curve_oid_len);
1096
1097 buf_incrwritepos(seq_buf,
1098 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 1, 2+1+pubkey_size, 0xa0));
1099 buf_incrwritepos(seq_buf,
1100 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 3, 1+pubkey_size, 0));
1101 buf_putbyte(seq_buf, 0);
1102 err = ecc_ansi_x963_export(*eck, buf_getwriteptr(seq_buf, pubkey_size), &pubkey_size);
1103 if (err != CRYPT_OK) {
1104 dropbear_exit("ECC error");
1105 }
1106 buf_incrwritepos(seq_buf, pubkey_size);
1107
1108 buf_setpos(seq_buf, 0);
1109
1110 outblob = (unsigned char*)m_malloc(1000);
1111
1112 pos = 0;
1113 pos += ber_write_id_len(outblob+pos, 16, seq_buf->len, ASN1_CONSTRUCTED);
1114 memcpy(&outblob[pos], seq_buf->data, seq_buf->len);
1115 pos += seq_buf->len;
1116 len = pos;
1117 outlen = len;
1118
1119 buf_burn(seq_buf);
1120 buf_free(seq_buf);
1121 seq_buf = NULL;
1122
1123 header = "-----BEGIN EC PRIVATE KEY-----\n";
1124 footer = "-----END EC PRIVATE KEY-----\n";
1125 }
1126 #endif
1127
1128 /*
1129 * Padding on OpenSSH keys is deterministic. The number of
1130 * padding bytes is always more than zero, and always at most
1131 * the cipher block length. The value of each padding byte is
1132 * equal to the number of padding bytes. So a plaintext that's
1133 * an exact multiple of the block size will be padded with 08
1134 * 08 08 08 08 08 08 08 (assuming a 64-bit block cipher); a
1135 * plaintext one byte less than a multiple of the block size
1136 * will be padded with just 01.
1137 *
1138 * This enables the OpenSSL key decryption function to strip
1139 * off the padding algorithmically and return the unpadded
1140 * plaintext to the next layer: it looks at the final byte, and
1141 * then expects to find that many bytes at the end of the data
1142 * with the same value. Those are all removed and the rest is
1143 * returned.
1144 */
1145 dropbear_assert(pos == len);
1146 while (pos < outlen) {
1147 outblob[pos++] = outlen - len;
1148 }
1149
1150 /*
1151 * Encrypt the key.
1152 */
1153 if (passphrase) {
1154 fprintf(stderr, "Encrypted keys aren't supported currently\n");
876 goto error; 1155 goto error;
877 } 1156 }
878 1157
879 /* e */ 1158 /*
880 numbers[2].bytes = buf_getint(keyblob); 1159 * And save it. We'll use Unix line endings just in case it's
881 numbers[2].start = buf_getptr(keyblob, numbers[2].bytes); 1160 * subsequently transferred in binary mode.
882 buf_incrpos(keyblob, numbers[2].bytes); 1161 */
883 1162 if (strlen(filename) == 1 && filename[0] == '-') {
884 /* n */ 1163 fp = stdout;
885 numbers[1].bytes = buf_getint(keyblob); 1164 } else {
886 numbers[1].start = buf_getptr(keyblob, numbers[1].bytes); 1165 fp = fopen(filename, "wb"); /* ensure Unix line endings */
887 buf_incrpos(keyblob, numbers[1].bytes); 1166 }
888 1167 if (!fp) {
889 /* d */ 1168 fprintf(stderr, "Failed opening output file\n");
890 numbers[3].bytes = buf_getint(keyblob); 1169 goto error;
891 numbers[3].start = buf_getptr(keyblob, numbers[3].bytes); 1170 }
892 buf_incrpos(keyblob, numbers[3].bytes); 1171 fputs(header, fp);
893 1172 base64_encode_fp(fp, outblob, outlen, 64);
894 /* p */ 1173 fputs(footer, fp);
895 numbers[4].bytes = buf_getint(keyblob); 1174 fclose(fp);
896 numbers[4].start = buf_getptr(keyblob, numbers[4].bytes); 1175 ret = 1;
897 buf_incrpos(keyblob, numbers[4].bytes); 1176
898 1177 error:
899 /* q */ 1178 if (outblob) {
900 numbers[5].bytes = buf_getint(keyblob); 1179 memset(outblob, 0, outlen);
901 numbers[5].start = buf_getptr(keyblob, numbers[5].bytes);
902 buf_incrpos(keyblob, numbers[5].bytes);
903
904 /* now calculate some extra parameters: */
905 m_mp_init(&tmpval);
906 m_mp_init(&dmp1);
907 m_mp_init(&dmq1);
908 m_mp_init(&iqmp);
909
910 /* dmp1 = d mod (p-1) */
911 if (mp_sub_d(key->rsakey->p, 1, &tmpval) != MP_OKAY) {
912 fprintf(stderr, "Bignum error for p-1\n");
913 goto error;
914 }
915 if (mp_mod(key->rsakey->d, &tmpval, &dmp1) != MP_OKAY) {
916 fprintf(stderr, "Bignum error for dmp1\n");
917 goto error;
918 }
919
920 /* dmq1 = d mod (q-1) */
921 if (mp_sub_d(key->rsakey->q, 1, &tmpval) != MP_OKAY) {
922 fprintf(stderr, "Bignum error for q-1\n");
923 goto error;
924 }
925 if (mp_mod(key->rsakey->d, &tmpval, &dmq1) != MP_OKAY) {
926 fprintf(stderr, "Bignum error for dmq1\n");
927 goto error;
928 }
929
930 /* iqmp = (q^-1) mod p */
931 if (mp_invmod(key->rsakey->q, key->rsakey->p, &iqmp) != MP_OKAY) {
932 fprintf(stderr, "Bignum error for iqmp\n");
933 goto error;
934 }
935
936 extrablob = buf_new(2000);
937 buf_putmpint(extrablob, &dmp1);
938 buf_putmpint(extrablob, &dmq1);
939 buf_putmpint(extrablob, &iqmp);
940 buf_setpos(extrablob, 0);
941 mp_clear(&dmp1);
942 mp_clear(&dmq1);
943 mp_clear(&iqmp);
944 mp_clear(&tmpval);
945
946 /* dmp1 */
947 numbers[6].bytes = buf_getint(extrablob);
948 numbers[6].start = buf_getptr(extrablob, numbers[6].bytes);
949 buf_incrpos(extrablob, numbers[6].bytes);
950
951 /* dmq1 */
952 numbers[7].bytes = buf_getint(extrablob);
953 numbers[7].start = buf_getptr(extrablob, numbers[7].bytes);
954 buf_incrpos(extrablob, numbers[7].bytes);
955
956 /* iqmp */
957 numbers[8].bytes = buf_getint(extrablob);
958 numbers[8].start = buf_getptr(extrablob, numbers[8].bytes);
959 buf_incrpos(extrablob, numbers[8].bytes);
960
961 nnumbers = 9;
962 header = "-----BEGIN RSA PRIVATE KEY-----\n";
963 footer = "-----END RSA PRIVATE KEY-----\n";
964 }
965 #endif /* DROPBEAR_RSA */
966
967 #ifdef DROPBEAR_DSS
968 if (key->type == DROPBEAR_SIGNKEY_DSS) {
969
970 /* p */
971 numbers[1].bytes = buf_getint(keyblob);
972 numbers[1].start = buf_getptr(keyblob, numbers[1].bytes);
973 buf_incrpos(keyblob, numbers[1].bytes);
974
975 /* q */
976 numbers[2].bytes = buf_getint(keyblob);
977 numbers[2].start = buf_getptr(keyblob, numbers[2].bytes);
978 buf_incrpos(keyblob, numbers[2].bytes);
979
980 /* g */
981 numbers[3].bytes = buf_getint(keyblob);
982 numbers[3].start = buf_getptr(keyblob, numbers[3].bytes);
983 buf_incrpos(keyblob, numbers[3].bytes);
984
985 /* y */
986 numbers[4].bytes = buf_getint(keyblob);
987 numbers[4].start = buf_getptr(keyblob, numbers[4].bytes);
988 buf_incrpos(keyblob, numbers[4].bytes);
989
990 /* x */
991 numbers[5].bytes = buf_getint(keyblob);
992 numbers[5].start = buf_getptr(keyblob, numbers[5].bytes);
993 buf_incrpos(keyblob, numbers[5].bytes);
994
995 nnumbers = 6;
996 header = "-----BEGIN DSA PRIVATE KEY-----\n";
997 footer = "-----END DSA PRIVATE KEY-----\n";
998 }
999 #endif /* DROPBEAR_DSS */
1000
1001 /*
1002 * Now count up the total size of the ASN.1 encoded integers,
1003 * so as to determine the length of the containing SEQUENCE.
1004 */
1005 len = 0;
1006 for (i = 0; i < nnumbers; i++) {
1007 len += ber_write_id_len(NULL, 2, numbers[i].bytes, 0);
1008 len += numbers[i].bytes;
1009 }
1010 seqlen = len;
1011 /* Now add on the SEQUENCE header. */
1012 len += ber_write_id_len(NULL, 16, seqlen, ASN1_CONSTRUCTED);
1013 /* Round up to the cipher block size, ensuring we have at least one
1014 * byte of padding (see below). */
1015 outlen = len;
1016 if (passphrase)
1017 outlen = (outlen+8) &~ 7;
1018
1019 /*
1020 * Now we know how big outblob needs to be. Allocate it.
1021 */
1022 outblob = (unsigned char*)m_malloc(outlen);
1023
1024 /*
1025 * And write the data into it.
1026 */
1027 pos = 0;
1028 pos += ber_write_id_len(outblob+pos, 16, seqlen, ASN1_CONSTRUCTED);
1029 for (i = 0; i < nnumbers; i++) {
1030 pos += ber_write_id_len(outblob+pos, 2, numbers[i].bytes, 0);
1031 memcpy(outblob+pos, numbers[i].start, numbers[i].bytes);
1032 pos += numbers[i].bytes;
1033 }
1034 } /* end RSA and DSS handling */
1035
1036 #ifdef DROPBEAR_ECDSA
1037 if (key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP256
1038 || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP384
1039 || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP521) {
1040
1041 /* SEC1 V2 appendix c.4
1042 ECPrivateKey ::= SEQUENCE {
1043 version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
1044 privateKey OCTET STRING,
1045 parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL,
1046 publicKey [1] BIT STRING OPTIONAL
1047 }
1048 */
1049 buffer *seq_buf = buf_new(400);
1050 ecc_key **eck = (ecc_key**)signkey_key_ptr(key, key->type);
1051 const long curve_size = (*eck)->dp->size;
1052 int curve_oid_len = 0;
1053 const void* curve_oid = NULL;
1054 unsigned long pubkey_size = 2*curve_size+1;
1055 int k_size;
1056 int err = 0;
1057
1058 /* version. less than 10 bytes */
1059 buf_incrwritepos(seq_buf,
1060 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 2, 1, 0));
1061 buf_putbyte(seq_buf, 1);
1062
1063 /* privateKey */
1064 k_size = mp_unsigned_bin_size((*eck)->k);
1065 dropbear_assert(k_size <= curve_size);
1066 buf_incrwritepos(seq_buf,
1067 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 4, k_size, 0));
1068 mp_to_unsigned_bin((*eck)->k, buf_getwriteptr(seq_buf, k_size));
1069 buf_incrwritepos(seq_buf, k_size);
1070
1071 /* SECGCurveNames */
1072 switch (key->type)
1073 {
1074 case DROPBEAR_SIGNKEY_ECDSA_NISTP256:
1075 curve_oid_len = sizeof(OID_SEC256R1_BLOB);
1076 curve_oid = OID_SEC256R1_BLOB;
1077 break;
1078 case DROPBEAR_SIGNKEY_ECDSA_NISTP384:
1079 curve_oid_len = sizeof(OID_SEC384R1_BLOB);
1080 curve_oid = OID_SEC384R1_BLOB;
1081 break;
1082 case DROPBEAR_SIGNKEY_ECDSA_NISTP521:
1083 curve_oid_len = sizeof(OID_SEC521R1_BLOB);
1084 curve_oid = OID_SEC521R1_BLOB;
1085 break;
1086 default:
1087 dropbear_exit("Internal error");
1088 }
1089
1090 buf_incrwritepos(seq_buf,
1091 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 0, 2+curve_oid_len, 0xa0));
1092 /* object == 6 */
1093 buf_incrwritepos(seq_buf,
1094 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 6, curve_oid_len, 0));
1095 buf_putbytes(seq_buf, curve_oid, curve_oid_len);
1096
1097 buf_incrwritepos(seq_buf,
1098 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 1, 2+1+pubkey_size, 0xa0));
1099 buf_incrwritepos(seq_buf,
1100 ber_write_id_len(buf_getwriteptr(seq_buf, 10), 3, 1+pubkey_size, 0));
1101 buf_putbyte(seq_buf, 0);
1102 err = ecc_ansi_x963_export(*eck, buf_getwriteptr(seq_buf, pubkey_size), &pubkey_size);
1103 if (err != CRYPT_OK) {
1104 dropbear_exit("ECC error");
1105 }
1106 buf_incrwritepos(seq_buf, pubkey_size);
1107
1108 buf_setpos(seq_buf, 0);
1109
1110 outblob = (unsigned char*)m_malloc(1000);
1111
1112 pos = 0;
1113 pos += ber_write_id_len(outblob+pos, 16, seq_buf->len, ASN1_CONSTRUCTED);
1114 memcpy(&outblob[pos], seq_buf->data, seq_buf->len);
1115 pos += seq_buf->len;
1116 len = pos;
1117 outlen = len;
1118
1119 buf_burn(seq_buf);
1120 buf_free(seq_buf);
1121 seq_buf = NULL;
1122
1123 header = "-----BEGIN EC PRIVATE KEY-----\n";
1124 footer = "-----END EC PRIVATE KEY-----\n";
1125 }
1126 #endif
1127
1128 /*
1129 * Padding on OpenSSH keys is deterministic. The number of
1130 * padding bytes is always more than zero, and always at most
1131 * the cipher block length. The value of each padding byte is
1132 * equal to the number of padding bytes. So a plaintext that's
1133 * an exact multiple of the block size will be padded with 08
1134 * 08 08 08 08 08 08 08 (assuming a 64-bit block cipher); a
1135 * plaintext one byte less than a multiple of the block size
1136 * will be padded with just 01.
1137 *
1138 * This enables the OpenSSL key decryption function to strip
1139 * off the padding algorithmically and return the unpadded
1140 * plaintext to the next layer: it looks at the final byte, and
1141 * then expects to find that many bytes at the end of the data
1142 * with the same value. Those are all removed and the rest is
1143 * returned.
1144 */
1145 dropbear_assert(pos == len);
1146 while (pos < outlen) {
1147 outblob[pos++] = outlen - len;
1148 }
1149
1150 /*
1151 * Encrypt the key.
1152 */
1153 if (passphrase) {
1154 fprintf(stderr, "Encrypted keys aren't supported currently\n");
1155 goto error;
1156 }
1157
1158 /*
1159 * And save it. We'll use Unix line endings just in case it's
1160 * subsequently transferred in binary mode.
1161 */
1162 if (strlen(filename) == 1 && filename[0] == '-') {
1163 fp = stdout;
1164 } else {
1165 fp = fopen(filename, "wb"); /* ensure Unix line endings */
1166 }
1167 if (!fp) {
1168 fprintf(stderr, "Failed opening output file\n");
1169 goto error;
1170 }
1171 fputs(header, fp);
1172 base64_encode_fp(fp, outblob, outlen, 64);
1173 fputs(footer, fp);
1174 fclose(fp);
1175 ret = 1;
1176
1177 error:
1178 if (outblob) {
1179 memset(outblob, 0, outlen);
1180 m_free(outblob); 1180 m_free(outblob);
1181 } 1181 }
1182 if (keyblob) { 1182 if (keyblob) {
1183 buf_burn(keyblob); 1183 buf_burn(keyblob);
1184 buf_free(keyblob); 1184 buf_free(keyblob);
1185 } 1185 }
1186 if (extrablob) { 1186 if (extrablob) {
1187 buf_burn(extrablob); 1187 buf_burn(extrablob);
1188 buf_free(extrablob); 1188 buf_free(extrablob);
1189 } 1189 }
1190 return ret; 1190 return ret;
1191 } 1191 }
1192 1192
1193 #if 0 1193 #if 0
1194 /* XXX TODO ssh.com stuff isn't going yet */ 1194 /* XXX TODO ssh.com stuff isn't going yet */
1195 1195
1268 */ 1268 */
1269 1269
1270 #define SSHCOM_MAGIC_NUMBER 0x3f6ff9eb 1270 #define SSHCOM_MAGIC_NUMBER 0x3f6ff9eb
1271 1271
1272 struct sshcom_key { 1272 struct sshcom_key {
1273 char comment[256]; /* allowing any length is overkill */ 1273 char comment[256]; /* allowing any length is overkill */
1274 unsigned char *keyblob; 1274 unsigned char *keyblob;
1275 int keyblob_len, keyblob_size; 1275 int keyblob_len, keyblob_size;
1276 }; 1276 };
1277 1277
1278 static struct sshcom_key *load_sshcom_key(const char *filename) 1278 static struct sshcom_key *load_sshcom_key(const char *filename)
1279 { 1279 {
1280 struct sshcom_key *ret; 1280 struct sshcom_key *ret;
1281 FILE *fp; 1281 FILE *fp;
1282 char buffer[256]; 1282 char buffer[256];
1283 int len; 1283 int len;
1284 char *errmsg, *p; 1284 char *errmsg, *p;
1285 int headers_done; 1285 int headers_done;
1286 char base64_bit[4]; 1286 char base64_bit[4];
1287 int base64_chars = 0; 1287 int base64_chars = 0;
1288 1288
1289 ret = snew(struct sshcom_key); 1289 ret = snew(struct sshcom_key);
1290 ret->comment[0] = '\0'; 1290 ret->comment[0] = '\0';
1291 ret->keyblob = NULL; 1291 ret->keyblob = NULL;
1292 ret->keyblob_len = ret->keyblob_size = 0; 1292 ret->keyblob_len = ret->keyblob_size = 0;
1293 1293
1294 fp = fopen(filename, "r"); 1294 fp = fopen(filename, "r");
1295 if (!fp) { 1295 if (!fp) {
1296 errmsg = "Unable to open key file"; 1296 errmsg = "Unable to open key file";
1297 goto error; 1297 goto error;
1298 } 1298 }
1299 if (!fgets(buffer, sizeof(buffer), fp) || 1299 if (!fgets(buffer, sizeof(buffer), fp) ||
1300 0 != strcmp(buffer, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n")) { 1300 0 != strcmp(buffer, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n")) {
1301 errmsg = "File does not begin with ssh.com key header"; 1301 errmsg = "File does not begin with ssh.com key header";
1302 goto error; 1302 goto error;
1303 } 1303 }
1304 1304
1305 headers_done = 0; 1305 headers_done = 0;
1306 while (1) { 1306 while (1) {
1307 if (!fgets(buffer, sizeof(buffer), fp)) { 1307 if (!fgets(buffer, sizeof(buffer), fp)) {
1308 errmsg = "Unexpected end of file"; 1308 errmsg = "Unexpected end of file";
1309 goto error; 1309 goto error;
1310 } 1310 }
1311 if (!strcmp(buffer, "---- END SSH2 ENCRYPTED PRIVATE KEY ----\n")) 1311 if (!strcmp(buffer, "---- END SSH2 ENCRYPTED PRIVATE KEY ----\n"))
1312 break; /* done */ 1312 break; /* done */
1313 if ((p = strchr(buffer, ':')) != NULL) { 1313 if ((p = strchr(buffer, ':')) != NULL) {
1314 if (headers_done) { 1314 if (headers_done) {
1315 errmsg = "Header found in body of key data"; 1315 errmsg = "Header found in body of key data";
1316 goto error; 1316 goto error;
1317 } 1317 }
1318 *p++ = '\0'; 1318 *p++ = '\0';
1319 while (*p && isspace((unsigned char)*p)) p++; 1319 while (*p && isspace((unsigned char)*p)) p++;
1320 /* 1320 /*
1321 * Header lines can end in a trailing backslash for 1321 * Header lines can end in a trailing backslash for
1322 * continuation. 1322 * continuation.
1323 */ 1323 */
1324 while ((len = strlen(p)) > (int)(sizeof(buffer) - (p-buffer) -1) || 1324 while ((len = strlen(p)) > (int)(sizeof(buffer) - (p-buffer) -1) ||
1325 p[len-1] != '\n' || p[len-2] == '\\') { 1325 p[len-1] != '\n' || p[len-2] == '\\') {
1326 if (len > (int)((p-buffer) + sizeof(buffer)-2)) { 1326 if (len > (int)((p-buffer) + sizeof(buffer)-2)) {
1327 errmsg = "Header line too long to deal with"; 1327 errmsg = "Header line too long to deal with";
1328 goto error; 1328 goto error;
1329 } 1329 }
1330 if (!fgets(p+len-2, sizeof(buffer)-(p-buffer)-(len-2), fp)) { 1330 if (!fgets(p+len-2, sizeof(buffer)-(p-buffer)-(len-2), fp)) {
1331 errmsg = "Unexpected end of file"; 1331 errmsg = "Unexpected end of file";
1332 goto error; 1332 goto error;
1333 } 1333 }
1334 } 1334 }
1335 p[strcspn(p, "\n")] = '\0'; 1335 p[strcspn(p, "\n")] = '\0';
1336 if (!strcmp(buffer, "Comment")) { 1336 if (!strcmp(buffer, "Comment")) {
1337 /* Strip quotes in comment if present. */ 1337 /* Strip quotes in comment if present. */
1338 if (p[0] == '"' && p[strlen(p)-1] == '"') { 1338 if (p[0] == '"' && p[strlen(p)-1] == '"') {
1339 p++; 1339 p++;
1340 p[strlen(p)-1] = '\0'; 1340 p[strlen(p)-1] = '\0';
1341 } 1341 }
1342 strncpy(ret->comment, p, sizeof(ret->comment)); 1342 strncpy(ret->comment, p, sizeof(ret->comment));
1343 ret->comment[sizeof(ret->comment)-1] = '\0'; 1343 ret->comment[sizeof(ret->comment)-1] = '\0';
1344 } 1344 }
1345 } else { 1345 } else {
1346 headers_done = 1; 1346 headers_done = 1;
1347 1347
1348 p = buffer; 1348 p = buffer;
1349 while (isbase64(*p)) { 1349 while (isbase64(*p)) {
1350 base64_bit[base64_chars++] = *p; 1350 base64_bit[base64_chars++] = *p;
1351 if (base64_chars == 4) { 1351 if (base64_chars == 4) {
1352 unsigned char out[3]; 1352 unsigned char out[3];
1353 1353
1354 base64_chars = 0; 1354 base64_chars = 0;
1355 1355
1356 len = base64_decode_atom(base64_bit, out); 1356 len = base64_decode_atom(base64_bit, out);
1357 1357
1358 if (len <= 0) { 1358 if (len <= 0) {
1359 errmsg = "Invalid base64 encoding"; 1359 errmsg = "Invalid base64 encoding";
1360 goto error; 1360 goto error;
1361 } 1361 }
1362 1362
1363 if (ret->keyblob_len + len > ret->keyblob_size) { 1363 if (ret->keyblob_len + len > ret->keyblob_size) {
1364 ret->keyblob_size = ret->keyblob_len + len + 256; 1364 ret->keyblob_size = ret->keyblob_len + len + 256;
1365 ret->keyblob = sresize(ret->keyblob, ret->keyblob_size, 1365 ret->keyblob = sresize(ret->keyblob, ret->keyblob_size,
1366 unsigned char); 1366 unsigned char);
1367 } 1367 }
1368 1368
1369 memcpy(ret->keyblob + ret->keyblob_len, out, len); 1369 memcpy(ret->keyblob + ret->keyblob_len, out, len);
1370 ret->keyblob_len += len; 1370 ret->keyblob_len += len;
1371 } 1371 }
1372 1372
1373 p++; 1373 p++;
1374 } 1374 }
1375 } 1375 }
1376 } 1376 }
1377 1377
1378 if (ret->keyblob_len == 0 || !ret->keyblob) { 1378 if (ret->keyblob_len == 0 || !ret->keyblob) {
1379 errmsg = "Key body not present"; 1379 errmsg = "Key body not present";
1380 goto error; 1380 goto error;
1381 } 1381 }
1382 1382
1383 return ret; 1383 return ret;
1384 1384
1385 error: 1385 error:
1386 if (ret) { 1386 if (ret) {
1387 if (ret->keyblob) { 1387 if (ret->keyblob) {
1388 memset(ret->keyblob, 0, ret->keyblob_size); 1388 memset(ret->keyblob, 0, ret->keyblob_size);
1389 m_free(ret->keyblob); 1389 m_free(ret->keyblob);
1390 } 1390 }
1391 memset(ret, 0, sizeof(*ret)); 1391 memset(ret, 0, sizeof(*ret));
1392 m_free(ret); 1392 m_free(ret);
1393 } 1393 }
1394 return NULL; 1394 return NULL;
1395 } 1395 }
1396 1396
1397 int sshcom_encrypted(const char *filename, char **comment) 1397 int sshcom_encrypted(const char *filename, char **comment)
1398 { 1398 {
1399 struct sshcom_key *key = load_sshcom_key(filename); 1399 struct sshcom_key *key = load_sshcom_key(filename);
1400 int pos, len, answer; 1400 int pos, len, answer;
1401 1401
1402 *comment = NULL; 1402 *comment = NULL;
1403 if (!key) 1403 if (!key)
1404 return 0; 1404 return 0;
1405 1405
1406 /* 1406 /*
1407 * Check magic number. 1407 * Check magic number.
1408 */ 1408 */
1409 if (GET_32BIT(key->keyblob) != 0x3f6ff9eb) 1409 if (GET_32BIT(key->keyblob) != 0x3f6ff9eb)
1410 return 0; /* key is invalid */ 1410 return 0; /* key is invalid */
1411 1411
1412 /* 1412 /*
1413 * Find the cipher-type string. 1413 * Find the cipher-type string.
1414 */ 1414 */
1415 answer = 0; 1415 answer = 0;
1416 pos = 8; 1416 pos = 8;
1417 if (key->keyblob_len < pos+4) 1417 if (key->keyblob_len < pos+4)
1418 goto done; /* key is far too short */ 1418 goto done; /* key is far too short */
1419 len = toint(GET_32BIT(key->keyblob + pos)); 1419 len = toint(GET_32BIT(key->keyblob + pos));
1420 if (len < 0 || len > key->keyblob_len - pos - 4) 1420 if (len < 0 || len > key->keyblob_len - pos - 4)
1421 goto done; /* key is far too short */ 1421 goto done; /* key is far too short */
1422 pos += 4 + len; /* skip key type */ 1422 pos += 4 + len; /* skip key type */
1423 len = toint(GET_32BIT(key->keyblob + pos)); /* find cipher-type length */ 1423 len = toint(GET_32BIT(key->keyblob + pos)); /* find cipher-type length */
1424 if (len < 0 || len > key->keyblob_len - pos - 4) 1424 if (len < 0 || len > key->keyblob_len - pos - 4)
1425 goto done; /* cipher type string is incomplete */ 1425 goto done; /* cipher type string is incomplete */
1426 if (len != 4 || 0 != memcmp(key->keyblob + pos + 4, "none", 4)) 1426 if (len != 4 || 0 != memcmp(key->keyblob + pos + 4, "none", 4))
1427 answer = 1; 1427 answer = 1;
1428 1428
1429 done: 1429 done:
1430 *comment = dupstr(key->comment); 1430 *comment = dupstr(key->comment);
1431 memset(key->keyblob, 0, key->keyblob_size); 1431 memset(key->keyblob, 0, key->keyblob_size);
1432 m_free(key->keyblob); 1432 m_free(key->keyblob);
1433 memset(key, 0, sizeof(*key)); 1433 memset(key, 0, sizeof(*key));
1434 m_free(key); 1434 m_free(key);
1435 return answer; 1435 return answer;
1436 } 1436 }
1437 1437
1438 static int sshcom_read_mpint(void *data, int len, struct mpint_pos *ret) 1438 static int sshcom_read_mpint(void *data, int len, struct mpint_pos *ret)
1439 { 1439 {
1440 unsigned bits, bytes; 1440 unsigned bits, bytes;
1441 unsigned char *d = (unsigned char *) data; 1441 unsigned char *d = (unsigned char *) data;
1442 1442
1443 if (len < 4) 1443 if (len < 4)
1444 goto error; 1444 goto error;
1445 bits = GET_32BIT(d); 1445 bits = GET_32BIT(d);
1446 1446
1447 bytes = (bits + 7) / 8; 1447 bytes = (bits + 7) / 8;
1448 if (len < 4+bytes) 1448 if (len < 4+bytes)
1449 goto error; 1449 goto error;
1450 1450
1451 ret->start = d + 4; 1451 ret->start = d + 4;
1452 ret->bytes = bytes; 1452 ret->bytes = bytes;
1453 return bytes+4; 1453 return bytes+4;
1454 1454
1455 error: 1455 error:
1456 ret->start = NULL; 1456 ret->start = NULL;
1457 ret->bytes = -1; 1457 ret->bytes = -1;
1458 return len; /* ensure further calls fail as well */ 1458 return len; /* ensure further calls fail as well */
1459 } 1459 }
1460 1460
1461 static int sshcom_put_mpint(void *target, void *data, int len) 1461 static int sshcom_put_mpint(void *target, void *data, int len)
1462 { 1462 {
1463 unsigned char *d = (unsigned char *)target; 1463 unsigned char *d = (unsigned char *)target;
1464 unsigned char *i = (unsigned char *)data; 1464 unsigned char *i = (unsigned char *)data;
1465 int bits = len * 8 - 1; 1465 int bits = len * 8 - 1;
1466 1466
1467 while (bits > 0) { 1467 while (bits > 0) {
1468 if (*i & (1 << (bits & 7))) 1468 if (*i & (1 << (bits & 7)))
1469 break; 1469 break;
1470 if (!(bits-- & 7)) 1470 if (!(bits-- & 7))
1471 i++, len--; 1471 i++, len--;
1472 } 1472 }
1473 1473
1474 PUT_32BIT(d, bits+1); 1474 PUT_32BIT(d, bits+1);
1475 memcpy(d+4, i, len); 1475 memcpy(d+4, i, len);
1476 return len+4; 1476 return len+4;
1477 } 1477 }
1478 1478
1479 sign_key *sshcom_read(const char *filename, char *passphrase) 1479 sign_key *sshcom_read(const char *filename, char *passphrase)
1480 { 1480 {
1481 struct sshcom_key *key = load_sshcom_key(filename); 1481 struct sshcom_key *key = load_sshcom_key(filename);
1482 char *errmsg; 1482 char *errmsg;
1483 int pos, len; 1483 int pos, len;
1484 const char prefix_rsa[] = "if-modn{sign{rsa"; 1484 const char prefix_rsa[] = "if-modn{sign{rsa";
1485 const char prefix_dsa[] = "dl-modp{sign{dsa"; 1485 const char prefix_dsa[] = "dl-modp{sign{dsa";
1486 enum { RSA, DSA } type; 1486 enum { RSA, DSA } type;
1487 int encrypted; 1487 int encrypted;
1488 char *ciphertext; 1488 char *ciphertext;
1489 int cipherlen; 1489 int cipherlen;
1490 struct ssh2_userkey *ret = NULL, *retkey; 1490 struct ssh2_userkey *ret = NULL, *retkey;
1491 const struct ssh_signkey *alg; 1491 const struct ssh_signkey *alg;
1492 unsigned char *blob = NULL; 1492 unsigned char *blob = NULL;
1493 int blobsize = 0, publen, privlen; 1493 int blobsize = 0, publen, privlen;
1494 1494
1495 if (!key) 1495 if (!key)
1496 return NULL; 1496 return NULL;
1497 1497
1498 /* 1498 /*
1499 * Check magic number. 1499 * Check magic number.
1500 */ 1500 */
1501 if (GET_32BIT(key->keyblob) != SSHCOM_MAGIC_NUMBER) { 1501 if (GET_32BIT(key->keyblob) != SSHCOM_MAGIC_NUMBER) {
1502 errmsg = "Key does not begin with magic number"; 1502 errmsg = "Key does not begin with magic number";
1503 goto error; 1503 goto error;
1504 } 1504 }
1505 1505
1506 /* 1506 /*
1507 * Determine the key type. 1507 * Determine the key type.
1508 */ 1508 */
1509 pos = 8; 1509 pos = 8;
1510 if (key->keyblob_len < pos+4 || 1510 if (key->keyblob_len < pos+4 ||
1511 (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { 1511 (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
1512 errmsg = "Key blob does not contain a key type string"; 1512 errmsg = "Key blob does not contain a key type string";
1513 goto error; 1513 goto error;
1514 } 1514 }
1515 if (len > sizeof(prefix_rsa) - 1 && 1515 if (len > sizeof(prefix_rsa) - 1 &&
1516 !memcmp(key->keyblob+pos+4, prefix_rsa, sizeof(prefix_rsa) - 1)) { 1516 !memcmp(key->keyblob+pos+4, prefix_rsa, sizeof(prefix_rsa) - 1)) {
1517 type = RSA; 1517 type = RSA;
1518 } else if (len > sizeof(prefix_dsa) - 1 && 1518 } else if (len > sizeof(prefix_dsa) - 1 &&
1519 !memcmp(key->keyblob+pos+4, prefix_dsa, sizeof(prefix_dsa) - 1)) { 1519 !memcmp(key->keyblob+pos+4, prefix_dsa, sizeof(prefix_dsa) - 1)) {
1520 type = DSA; 1520 type = DSA;
1521 } else { 1521 } else {
1522 errmsg = "Key is of unknown type"; 1522 errmsg = "Key is of unknown type";
1523 goto error; 1523 goto error;
1524 } 1524 }
1525 pos += 4+len; 1525 pos += 4+len;
1526 1526
1527 /* 1527 /*
1528 * Determine the cipher type. 1528 * Determine the cipher type.
1529 */ 1529 */
1530 if (key->keyblob_len < pos+4 || 1530 if (key->keyblob_len < pos+4 ||
1531 (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { 1531 (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
1532 errmsg = "Key blob does not contain a cipher type string"; 1532 errmsg = "Key blob does not contain a cipher type string";
1533 goto error; 1533 goto error;
1534 } 1534 }
1535 if (len == 4 && !memcmp(key->keyblob+pos+4, "none", 4)) 1535 if (len == 4 && !memcmp(key->keyblob+pos+4, "none", 4))
1536 encrypted = 0; 1536 encrypted = 0;
1537 else if (len == 8 && !memcmp(key->keyblob+pos+4, "3des-cbc", 8)) 1537 else if (len == 8 && !memcmp(key->keyblob+pos+4, "3des-cbc", 8))
1538 encrypted = 1; 1538 encrypted = 1;
1539 else { 1539 else {
1540 errmsg = "Key encryption is of unknown type"; 1540 errmsg = "Key encryption is of unknown type";
1541 goto error; 1541 goto error;
1542 } 1542 }
1543 pos += 4+len; 1543 pos += 4+len;
1544 1544
1545 /* 1545 /*
1546 * Get hold of the encrypted part of the key. 1546 * Get hold of the encrypted part of the key.
1547 */ 1547 */
1548 if (key->keyblob_len < pos+4 || 1548 if (key->keyblob_len < pos+4 ||
1549 (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { 1549 (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
1550 errmsg = "Key blob does not contain actual key data"; 1550 errmsg = "Key blob does not contain actual key data";
1551 goto error; 1551 goto error;
1552 } 1552 }
1553 ciphertext = (char *)key->keyblob + pos + 4; 1553 ciphertext = (char *)key->keyblob + pos + 4;
1554 cipherlen = len; 1554 cipherlen = len;
1555 if (cipherlen == 0) { 1555 if (cipherlen == 0) {
1556 errmsg = "Length of key data is zero"; 1556 errmsg = "Length of key data is zero";
1557 goto error; 1557 goto error;
1558 } 1558 }
1559 1559
1560 /* 1560 /*
1561 * Decrypt it if necessary. 1561 * Decrypt it if necessary.
1562 */ 1562 */
1563 if (encrypted) { 1563 if (encrypted) {
1564 /* 1564 /*
1565 * Derive encryption key from passphrase and iv/salt: 1565 * Derive encryption key from passphrase and iv/salt:
1566 * 1566 *
1567 * - let block A equal MD5(passphrase) 1567 * - let block A equal MD5(passphrase)
1568 * - let block B equal MD5(passphrase || A) 1568 * - let block B equal MD5(passphrase || A)
1569 * - block C would be MD5(passphrase || A || B) and so on 1569 * - block C would be MD5(passphrase || A || B) and so on
1570 * - encryption key is the first N bytes of A || B 1570 * - encryption key is the first N bytes of A || B
1571 */ 1571 */
1572 struct MD5Context md5c; 1572 struct MD5Context md5c;
1573 unsigned char keybuf[32], iv[8]; 1573 unsigned char keybuf[32], iv[8];
1574 1574
1575 if (cipherlen % 8 != 0) { 1575 if (cipherlen % 8 != 0) {
1576 errmsg = "Encrypted part of key is not a multiple of cipher block" 1576 errmsg = "Encrypted part of key is not a multiple of cipher block"
1577 " size"; 1577 " size";
1578 goto error; 1578 goto error;
1579 } 1579 }
1580 1580
1581 MD5Init(&md5c); 1581 MD5Init(&md5c);
1582 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); 1582 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
1583 MD5Final(keybuf, &md5c); 1583 MD5Final(keybuf, &md5c);
1584 1584
1585 MD5Init(&md5c); 1585 MD5Init(&md5c);
1586 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); 1586 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
1587 MD5Update(&md5c, keybuf, 16); 1587 MD5Update(&md5c, keybuf, 16);
1588 MD5Final(keybuf+16, &md5c); 1588 MD5Final(keybuf+16, &md5c);
1589 1589
1590 /* 1590 /*
1591 * Now decrypt the key blob. 1591 * Now decrypt the key blob.
1592 */ 1592 */
1593 memset(iv, 0, sizeof(iv)); 1593 memset(iv, 0, sizeof(iv));
1594 des3_decrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext, 1594 des3_decrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext,
1595 cipherlen); 1595 cipherlen);
1596 1596
1597 memset(&md5c, 0, sizeof(md5c)); 1597 memset(&md5c, 0, sizeof(md5c));
1598 memset(keybuf, 0, sizeof(keybuf)); 1598 memset(keybuf, 0, sizeof(keybuf));
1599 1599
1600 /* 1600 /*
1601 * Hereafter we return WRONG_PASSPHRASE for any parsing 1601 * Hereafter we return WRONG_PASSPHRASE for any parsing
1602 * error. (But only if we've just tried to decrypt it! 1602 * error. (But only if we've just tried to decrypt it!
1603 * Returning WRONG_PASSPHRASE for an unencrypted key is 1603 * Returning WRONG_PASSPHRASE for an unencrypted key is
1604 * automatic doom.) 1604 * automatic doom.)
1605 */ 1605 */
1606 if (encrypted) 1606 if (encrypted)
1607 ret = SSH2_WRONG_PASSPHRASE; 1607 ret = SSH2_WRONG_PASSPHRASE;
1608 } 1608 }
1609 1609
1610 /* 1610 /*
1611 * Strip away the containing string to get to the real meat. 1611 * Strip away the containing string to get to the real meat.
1612 */ 1612 */
1613 len = toint(GET_32BIT(ciphertext)); 1613 len = toint(GET_32BIT(ciphertext));
1614 if (len < 0 || len > cipherlen-4) { 1614 if (len < 0 || len > cipherlen-4) {
1615 errmsg = "containing string was ill-formed"; 1615 errmsg = "containing string was ill-formed";
1616 goto error; 1616 goto error;
1617 } 1617 }
1618 ciphertext += 4; 1618 ciphertext += 4;
1619 cipherlen = len; 1619 cipherlen = len;
1620 1620
1621 /* 1621 /*
1622 * Now we break down into RSA versus DSA. In either case we'll 1622 * Now we break down into RSA versus DSA. In either case we'll
1623 * construct public and private blobs in our own format, and 1623 * construct public and private blobs in our own format, and
1624 * end up feeding them to alg->createkey(). 1624 * end up feeding them to alg->createkey().
1625 */ 1625 */
1626 blobsize = cipherlen + 256; 1626 blobsize = cipherlen + 256;
1627 blob = snewn(blobsize, unsigned char); 1627 blob = snewn(blobsize, unsigned char);
1628 privlen = 0; 1628 privlen = 0;
1629 if (type == RSA) { 1629 if (type == RSA) {
1630 struct mpint_pos n, e, d, u, p, q; 1630 struct mpint_pos n, e, d, u, p, q;
1631 int pos = 0; 1631 int pos = 0;
1632 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &e); 1632 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &e);
1633 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &d); 1633 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &d);
1634 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &n); 1634 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &n);
1635 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &u); 1635 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &u);
1636 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p); 1636 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p);
1637 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q); 1637 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q);
1638 if (!q.start) { 1638 if (!q.start) {
1639 errmsg = "key data did not contain six integers"; 1639 errmsg = "key data did not contain six integers";
1640 goto error; 1640 goto error;
1641 } 1641 }
1642 1642
1643 alg = &ssh_rsa; 1643 alg = &ssh_rsa;
1644 pos = 0; 1644 pos = 0;
1645 pos += put_string(blob+pos, "ssh-rsa", 7); 1645 pos += put_string(blob+pos, "ssh-rsa", 7);
1646 pos += put_mp(blob+pos, e.start, e.bytes); 1646 pos += put_mp(blob+pos, e.start, e.bytes);
1647 pos += put_mp(blob+pos, n.start, n.bytes); 1647 pos += put_mp(blob+pos, n.start, n.bytes);
1648 publen = pos; 1648 publen = pos;
1649 pos += put_string(blob+pos, d.start, d.bytes); 1649 pos += put_string(blob+pos, d.start, d.bytes);
1650 pos += put_mp(blob+pos, q.start, q.bytes); 1650 pos += put_mp(blob+pos, q.start, q.bytes);
1651 pos += put_mp(blob+pos, p.start, p.bytes); 1651 pos += put_mp(blob+pos, p.start, p.bytes);
1652 pos += put_mp(blob+pos, u.start, u.bytes); 1652 pos += put_mp(blob+pos, u.start, u.bytes);
1653 privlen = pos - publen; 1653 privlen = pos - publen;
1654 } else if (type == DSA) { 1654 } else if (type == DSA) {
1655 struct mpint_pos p, q, g, x, y; 1655 struct mpint_pos p, q, g, x, y;
1656 int pos = 4; 1656 int pos = 4;
1657 if (GET_32BIT(ciphertext) != 0) { 1657 if (GET_32BIT(ciphertext) != 0) {
1658 errmsg = "predefined DSA parameters not supported"; 1658 errmsg = "predefined DSA parameters not supported";
1659 goto error; 1659 goto error;
1660 } 1660 }
1661 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p); 1661 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p);
1662 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &g); 1662 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &g);
1663 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q); 1663 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q);
1664 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &y); 1664 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &y);
1665 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &x); 1665 pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &x);
1666 if (!x.start) { 1666 if (!x.start) {
1667 errmsg = "key data did not contain five integers"; 1667 errmsg = "key data did not contain five integers";
1668 goto error; 1668 goto error;
1669 } 1669 }
1670 1670
1671 alg = &ssh_dss; 1671 alg = &ssh_dss;
1672 pos = 0; 1672 pos = 0;
1673 pos += put_string(blob+pos, "ssh-dss", 7); 1673 pos += put_string(blob+pos, "ssh-dss", 7);
1674 pos += put_mp(blob+pos, p.start, p.bytes); 1674 pos += put_mp(blob+pos, p.start, p.bytes);
1675 pos += put_mp(blob+pos, q.start, q.bytes); 1675 pos += put_mp(blob+pos, q.start, q.bytes);
1676 pos += put_mp(blob+pos, g.start, g.bytes); 1676 pos += put_mp(blob+pos, g.start, g.bytes);
1677 pos += put_mp(blob+pos, y.start, y.bytes); 1677 pos += put_mp(blob+pos, y.start, y.bytes);
1678 publen = pos; 1678 publen = pos;
1679 pos += put_mp(blob+pos, x.start, x.bytes); 1679 pos += put_mp(blob+pos, x.start, x.bytes);
1680 privlen = pos - publen; 1680 privlen = pos - publen;
1681 } else 1681 } else
1682 return NULL; 1682 return NULL;
1683 1683
1684 dropbear_assert(privlen > 0); /* should have bombed by now if not */ 1684 dropbear_assert(privlen > 0); /* should have bombed by now if not */
1685 1685
1686 retkey = snew(struct ssh2_userkey); 1686 retkey = snew(struct ssh2_userkey);
1687 retkey->alg = alg; 1687 retkey->alg = alg;
1688 retkey->data = alg->createkey(blob, publen, blob+publen, privlen); 1688 retkey->data = alg->createkey(blob, publen, blob+publen, privlen);
1689 if (!retkey->data) { 1689 if (!retkey->data) {
1690 m_free(retkey); 1690 m_free(retkey);
1691 errmsg = "unable to create key data structure"; 1691 errmsg = "unable to create key data structure";
1692 goto error; 1692 goto error;
1693 } 1693 }
1694 retkey->comment = dupstr(key->comment); 1694 retkey->comment = dupstr(key->comment);
1695 1695
1696 errmsg = NULL; /* no error */ 1696 errmsg = NULL; /* no error */
1697 ret = retkey; 1697 ret = retkey;
1698 1698
1699 error: 1699 error:
1700 if (blob) { 1700 if (blob) {
1701 memset(blob, 0, blobsize); 1701 memset(blob, 0, blobsize);
1702 m_free(blob); 1702 m_free(blob);
1703 } 1703 }
1704 memset(key->keyblob, 0, key->keyblob_size); 1704 memset(key->keyblob, 0, key->keyblob_size);
1705 m_free(key->keyblob); 1705 m_free(key->keyblob);
1706 memset(key, 0, sizeof(*key)); 1706 memset(key, 0, sizeof(*key));
1707 m_free(key); 1707 m_free(key);
1708 return ret; 1708 return ret;
1709 } 1709 }
1710 1710
1711 int sshcom_write(const char *filename, sign_key *key, 1711 int sshcom_write(const char *filename, sign_key *key,
1712 char *passphrase) 1712 char *passphrase)
1713 { 1713 {
1714 unsigned char *pubblob, *privblob; 1714 unsigned char *pubblob, *privblob;
1715 int publen, privlen; 1715 int publen, privlen;
1716 unsigned char *outblob; 1716 unsigned char *outblob;
1717 int outlen; 1717 int outlen;
1718 struct mpint_pos numbers[6]; 1718 struct mpint_pos numbers[6];
1719 int nnumbers, initial_zero, pos, lenpos, i; 1719 int nnumbers, initial_zero, pos, lenpos, i;
1720 char *type; 1720 char *type;
1721 char *ciphertext; 1721 char *ciphertext;
1722 int cipherlen; 1722 int cipherlen;
1723 int ret = 0; 1723 int ret = 0;
1724 FILE *fp; 1724 FILE *fp;
1725 1725
1726 /* 1726 /*
1727 * Fetch the key blobs. 1727 * Fetch the key blobs.
1728 */ 1728 */
1729 pubblob = key->alg->public_blob(key->data, &publen); 1729 pubblob = key->alg->public_blob(key->data, &publen);
1730 privblob = key->alg->private_blob(key->data, &privlen); 1730 privblob = key->alg->private_blob(key->data, &privlen);
1731 outblob = NULL; 1731 outblob = NULL;
1732 1732
1733 /* 1733 /*
1734 * Find the sequence of integers to be encoded into the OpenSSH 1734 * Find the sequence of integers to be encoded into the OpenSSH
1735 * key blob, and also decide on the header line. 1735 * key blob, and also decide on the header line.
1736 */ 1736 */
1737 if (key->alg == &ssh_rsa) { 1737 if (key->alg == &ssh_rsa) {
1738 int pos; 1738 int pos;
1739 struct mpint_pos n, e, d, p, q, iqmp; 1739 struct mpint_pos n, e, d, p, q, iqmp;
1740 1740
1741 pos = 4 + GET_32BIT(pubblob); 1741 pos = 4 + GET_32BIT(pubblob);
1742 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &e); 1742 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &e);
1743 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &n); 1743 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &n);
1744 pos = 0; 1744 pos = 0;
1745 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &d); 1745 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &d);
1746 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &p); 1746 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &p);
1747 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &q); 1747 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &q);
1748 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &iqmp); 1748 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &iqmp);
1749 1749
1750 dropbear_assert(e.start && iqmp.start); /* can't go wrong */ 1750 dropbear_assert(e.start && iqmp.start); /* can't go wrong */
1751 1751
1752 numbers[0] = e; 1752 numbers[0] = e;
1753 numbers[1] = d; 1753 numbers[1] = d;
1754 numbers[2] = n; 1754 numbers[2] = n;
1755 numbers[3] = iqmp; 1755 numbers[3] = iqmp;
1756 numbers[4] = q; 1756 numbers[4] = q;
1757 numbers[5] = p; 1757 numbers[5] = p;
1758 1758
1759 nnumbers = 6; 1759 nnumbers = 6;
1760 initial_zero = 0; 1760 initial_zero = 0;
1761 type = "if-modn{sign{rsa-pkcs1-sha1},encrypt{rsa-pkcs1v2-oaep}}"; 1761 type = "if-modn{sign{rsa-pkcs1-sha1},encrypt{rsa-pkcs1v2-oaep}}";
1762 } else if (key->alg == &ssh_dss) { 1762 } else if (key->alg == &ssh_dss) {
1763 int pos; 1763 int pos;
1764 struct mpint_pos p, q, g, y, x; 1764 struct mpint_pos p, q, g, y, x;
1765 1765
1766 pos = 4 + GET_32BIT(pubblob); 1766 pos = 4 + GET_32BIT(pubblob);
1767 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &p); 1767 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &p);
1768 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &q); 1768 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &q);
1769 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &g); 1769 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &g);
1770 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &y); 1770 pos += ssh2_read_mpint(pubblob+pos, publen-pos, &y);
1771 pos = 0; 1771 pos = 0;
1772 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &x); 1772 pos += ssh2_read_mpint(privblob+pos, privlen-pos, &x);
1773 1773
1774 dropbear_assert(y.start && x.start); /* can't go wrong */ 1774 dropbear_assert(y.start && x.start); /* can't go wrong */
1775 1775
1776 numbers[0] = p; 1776 numbers[0] = p;
1777 numbers[1] = g; 1777 numbers[1] = g;
1778 numbers[2] = q; 1778 numbers[2] = q;
1779 numbers[3] = y; 1779 numbers[3] = y;
1780 numbers[4] = x; 1780 numbers[4] = x;
1781 1781
1782 nnumbers = 5; 1782 nnumbers = 5;
1783 initial_zero = 1; 1783 initial_zero = 1;
1784 type = "dl-modp{sign{dsa-nist-sha1},dh{plain}}"; 1784 type = "dl-modp{sign{dsa-nist-sha1},dh{plain}}";
1785 } else { 1785 } else {
1786 dropbear_assert(0); /* zoinks! */ 1786 dropbear_assert(0); /* zoinks! */
1787 } 1787 }
1788 1788
1789 /* 1789 /*
1790 * Total size of key blob will be somewhere under 512 plus 1790 * Total size of key blob will be somewhere under 512 plus
1791 * combined length of integers. We'll calculate the more 1791 * combined length of integers. We'll calculate the more
1792 * precise size as we construct the blob. 1792 * precise size as we construct the blob.
1793 */ 1793 */
1794 outlen = 512; 1794 outlen = 512;
1795 for (i = 0; i < nnumbers; i++) 1795 for (i = 0; i < nnumbers; i++)
1796 outlen += 4 + numbers[i].bytes; 1796 outlen += 4 + numbers[i].bytes;
1797 outblob = snewn(outlen, unsigned char); 1797 outblob = snewn(outlen, unsigned char);
1798 1798
1799 /* 1799 /*
1800 * Create the unencrypted key blob. 1800 * Create the unencrypted key blob.
1801 */ 1801 */
1802 pos = 0; 1802 pos = 0;
1803 PUT_32BIT(outblob+pos, SSHCOM_MAGIC_NUMBER); pos += 4; 1803 PUT_32BIT(outblob+pos, SSHCOM_MAGIC_NUMBER); pos += 4;
1804 pos += 4; /* length field, fill in later */ 1804 pos += 4; /* length field, fill in later */
1805 pos += put_string(outblob+pos, type, strlen(type)); 1805 pos += put_string(outblob+pos, type, strlen(type));
1806 { 1806 {
1807 char *ciphertype = passphrase ? "3des-cbc" : "none"; 1807 char *ciphertype = passphrase ? "3des-cbc" : "none";
1808 pos += put_string(outblob+pos, ciphertype, strlen(ciphertype)); 1808 pos += put_string(outblob+pos, ciphertype, strlen(ciphertype));
1809 } 1809 }
1810 lenpos = pos; /* remember this position */ 1810 lenpos = pos; /* remember this position */
1811 pos += 4; /* encrypted-blob size */ 1811 pos += 4; /* encrypted-blob size */
1812 pos += 4; /* encrypted-payload size */ 1812 pos += 4; /* encrypted-payload size */
1813 if (initial_zero) { 1813 if (initial_zero) {
1814 PUT_32BIT(outblob+pos, 0); 1814 PUT_32BIT(outblob+pos, 0);
1815 pos += 4; 1815 pos += 4;
1816 } 1816 }
1817 for (i = 0; i < nnumbers; i++) 1817 for (i = 0; i < nnumbers; i++)
1818 pos += sshcom_put_mpint(outblob+pos, 1818 pos += sshcom_put_mpint(outblob+pos,
1819 numbers[i].start, numbers[i].bytes); 1819 numbers[i].start, numbers[i].bytes);
1820 /* Now wrap up the encrypted payload. */ 1820 /* Now wrap up the encrypted payload. */
1821 PUT_32BIT(outblob+lenpos+4, pos - (lenpos+8)); 1821 PUT_32BIT(outblob+lenpos+4, pos - (lenpos+8));
1822 /* Pad encrypted blob to a multiple of cipher block size. */ 1822 /* Pad encrypted blob to a multiple of cipher block size. */
1823 if (passphrase) { 1823 if (passphrase) {
1824 int padding = -(pos - (lenpos+4)) & 7; 1824 int padding = -(pos - (lenpos+4)) & 7;
1825 while (padding--) 1825 while (padding--)
1826 outblob[pos++] = random_byte(); 1826 outblob[pos++] = random_byte();
1827 } 1827 }
1828 ciphertext = (char *)outblob+lenpos+4; 1828 ciphertext = (char *)outblob+lenpos+4;
1829 cipherlen = pos - (lenpos+4); 1829 cipherlen = pos - (lenpos+4);
1830 dropbear_assert(!passphrase || cipherlen % 8 == 0); 1830 dropbear_assert(!passphrase || cipherlen % 8 == 0);
1831 /* Wrap up the encrypted blob string. */ 1831 /* Wrap up the encrypted blob string. */
1832 PUT_32BIT(outblob+lenpos, cipherlen); 1832 PUT_32BIT(outblob+lenpos, cipherlen);
1833 /* And finally fill in the total length field. */ 1833 /* And finally fill in the total length field. */
1834 PUT_32BIT(outblob+4, pos); 1834 PUT_32BIT(outblob+4, pos);
1835 1835
1836 dropbear_assert(pos < outlen); 1836 dropbear_assert(pos < outlen);
1837 1837
1838 /* 1838 /*
1839 * Encrypt the key. 1839 * Encrypt the key.
1840 */ 1840 */
1841 if (passphrase) { 1841 if (passphrase) {
1842 /* 1842 /*
1843 * Derive encryption key from passphrase and iv/salt: 1843 * Derive encryption key from passphrase and iv/salt:
1844 * 1844 *
1845 * - let block A equal MD5(passphrase) 1845 * - let block A equal MD5(passphrase)
1846 * - let block B equal MD5(passphrase || A) 1846 * - let block B equal MD5(passphrase || A)
1847 * - block C would be MD5(passphrase || A || B) and so on 1847 * - block C would be MD5(passphrase || A || B) and so on
1848 * - encryption key is the first N bytes of A || B 1848 * - encryption key is the first N bytes of A || B
1849 */ 1849 */
1850 struct MD5Context md5c; 1850 struct MD5Context md5c;
1851 unsigned char keybuf[32], iv[8]; 1851 unsigned char keybuf[32], iv[8];
1852 1852
1853 MD5Init(&md5c); 1853 MD5Init(&md5c);
1854 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); 1854 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
1855 MD5Final(keybuf, &md5c); 1855 MD5Final(keybuf, &md5c);
1856 1856
1857 MD5Init(&md5c); 1857 MD5Init(&md5c);
1858 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); 1858 MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
1859 MD5Update(&md5c, keybuf, 16); 1859 MD5Update(&md5c, keybuf, 16);
1860 MD5Final(keybuf+16, &md5c); 1860 MD5Final(keybuf+16, &md5c);
1861 1861
1862 /* 1862 /*
1863 * Now decrypt the key blob. 1863 * Now decrypt the key blob.
1864 */ 1864 */
1865 memset(iv, 0, sizeof(iv)); 1865 memset(iv, 0, sizeof(iv));
1866 des3_encrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext, 1866 des3_encrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext,
1867 cipherlen); 1867 cipherlen);
1868 1868
1869 memset(&md5c, 0, sizeof(md5c)); 1869 memset(&md5c, 0, sizeof(md5c));
1870 memset(keybuf, 0, sizeof(keybuf)); 1870 memset(keybuf, 0, sizeof(keybuf));
1871 } 1871 }
1872 1872
1873 /* 1873 /*
1874 * And save it. We'll use Unix line endings just in case it's 1874 * And save it. We'll use Unix line endings just in case it's
1875 * subsequently transferred in binary mode. 1875 * subsequently transferred in binary mode.
1876 */ 1876 */
1877 fp = fopen(filename, "wb"); /* ensure Unix line endings */ 1877 fp = fopen(filename, "wb"); /* ensure Unix line endings */
1878 if (!fp) 1878 if (!fp)
1879 goto error; 1879 goto error;
1880 fputs("---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n", fp); 1880 fputs("---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n", fp);
1881 fprintf(fp, "Comment: \""); 1881 fprintf(fp, "Comment: \"");
1882 /* 1882 /*
1883 * Comment header is broken with backslash-newline if it goes 1883 * Comment header is broken with backslash-newline if it goes
1884 * over 70 chars. Although it's surrounded by quotes, it 1884 * over 70 chars. Although it's surrounded by quotes, it
1885 * _doesn't_ escape backslashes or quotes within the string. 1885 * _doesn't_ escape backslashes or quotes within the string.
1886 * Don't ask me, I didn't design it. 1886 * Don't ask me, I didn't design it.
1887 */ 1887 */
1888 { 1888 {
1889 int slen = 60; /* starts at 60 due to "Comment: " */ 1889 int slen = 60; /* starts at 60 due to "Comment: " */
1890 char *c = key->comment; 1890 char *c = key->comment;
1891 while ((int)strlen(c) > slen) { 1891 while ((int)strlen(c) > slen) {
1892 fprintf(fp, "%.*s\\\n", slen, c); 1892 fprintf(fp, "%.*s\\\n", slen, c);
1893 c += slen; 1893 c += slen;
1894 slen = 70; /* allow 70 chars on subsequent lines */ 1894 slen = 70; /* allow 70 chars on subsequent lines */
1895 } 1895 }
1896 fprintf(fp, "%s\"\n", c); 1896 fprintf(fp, "%s\"\n", c);
1897 } 1897 }
1898 base64_encode_fp(fp, outblob, pos, 70); 1898 base64_encode_fp(fp, outblob, pos, 70);
1899 fputs("---- END SSH2 ENCRYPTED PRIVATE KEY ----\n", fp); 1899 fputs("---- END SSH2 ENCRYPTED PRIVATE KEY ----\n", fp);
1900 fclose(fp); 1900 fclose(fp);
1901 ret = 1; 1901 ret = 1;
1902 1902
1903 error: 1903 error:
1904 if (outblob) { 1904 if (outblob) {
1905 memset(outblob, 0, outlen); 1905 memset(outblob, 0, outlen);
1906 m_free(outblob); 1906 m_free(outblob);
1907 } 1907 }
1908 if (privblob) { 1908 if (privblob) {
1909 memset(privblob, 0, privlen); 1909 memset(privblob, 0, privlen);
1910 m_free(privblob); 1910 m_free(privblob);
1911 } 1911 }
1912 if (pubblob) { 1912 if (pubblob) {
1913 memset(pubblob, 0, publen); 1913 memset(pubblob, 0, publen);
1914 m_free(pubblob); 1914 m_free(pubblob);
1915 } 1915 }
1916 return ret; 1916 return ret;
1917 } 1917 }
1918 #endif /* ssh.com stuff disabled */ 1918 #endif /* ssh.com stuff disabled */
1919 1919
1920 /* From PuTTY misc.c */ 1920 /* From PuTTY misc.c */
1921 static int toint(unsigned u) 1921 static int toint(unsigned u)
1922 { 1922 {
1923 /* 1923 /*
1924 * Convert an unsigned to an int, without running into the 1924 * Convert an unsigned to an int, without running into the
1925 * undefined behaviour which happens by the strict C standard if 1925 * undefined behaviour which happens by the strict C standard if
1926 * the value overflows. You'd hope that sensible compilers would 1926 * the value overflows. You'd hope that sensible compilers would
1927 * do the sensible thing in response to a cast, but actually I 1927 * do the sensible thing in response to a cast, but actually I
1928 * don't trust modern compilers not to do silly things like 1928 * don't trust modern compilers not to do silly things like
1929 * assuming that _obviously_ you wouldn't have caused an overflow 1929 * assuming that _obviously_ you wouldn't have caused an overflow
1930 * and so they can elide an 'if (i < 0)' test immediately after 1930 * and so they can elide an 'if (i < 0)' test immediately after
1931 * the cast. 1931 * the cast.
1932 * 1932 *
1933 * Sensible compilers ought of course to optimise this entire 1933 * Sensible compilers ought of course to optimise this entire
1934 * function into 'just return the input value'! 1934 * function into 'just return the input value'!
1935 */ 1935 */
1936 if (u <= (unsigned)INT_MAX) 1936 if (u <= (unsigned)INT_MAX)
1937 return (int)u; 1937 return (int)u;
1938 else if (u >= (unsigned)INT_MIN) /* wrap in cast _to_ unsigned is OK */ 1938 else if (u >= (unsigned)INT_MIN) /* wrap in cast _to_ unsigned is OK */
1939 return INT_MIN + (int)(u - (unsigned)INT_MIN); 1939 return INT_MIN + (int)(u - (unsigned)INT_MIN);
1940 else 1940 else
1941 return INT_MIN; /* fallback; should never occur on binary machines */ 1941 return INT_MIN; /* fallback; should never occur on binary machines */
1942 } 1942 }