1 /*
2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdio.h>
11 #include "crypto/ctype.h"
12 #include <string.h>
13 #include "internal/cryptlib.h"
14 #include <openssl/buffer.h>
15 #include <openssl/objects.h>
16 #include <openssl/evp.h>
17 #include <openssl/rand.h>
18 #include <openssl/x509.h>
19 #include <openssl/pem.h>
20 #include <openssl/pkcs12.h>
21 #include "crypto/asn1.h"
22 #include <openssl/des.h>
23 #include <openssl/engine.h>
24
25 #define MIN_LENGTH 4
26
27 static int load_iv(char **fromp, unsigned char *to, int num);
28 static int check_pem(const char *nm, const char *name);
29 int pem_check_suffix(const char *pem_str, const char *suffix);
30
PEM_def_callback(char * buf,int num,int rwflag,void * userdata)31 int PEM_def_callback(char *buf, int num, int rwflag, void *userdata)
32 {
33 int i, min_len;
34 const char *prompt;
35
36 /* We assume that the user passes a default password as userdata */
37 if (userdata) {
38 i = strlen(userdata);
39 i = (i > num) ? num : i;
40 memcpy(buf, userdata, i);
41 return i;
42 }
43
44 prompt = EVP_get_pw_prompt();
45 if (prompt == NULL)
46 prompt = "Enter PEM pass phrase:";
47
48 /*
49 * rwflag == 0 means decryption
50 * rwflag == 1 means encryption
51 *
52 * We assume that for encryption, we want a minimum length, while for
53 * decryption, we cannot know any minimum length, so we assume zero.
54 */
55 min_len = rwflag ? MIN_LENGTH : 0;
56
57 i = EVP_read_pw_string_min(buf, min_len, num, prompt, rwflag);
58 if (i != 0) {
59 PEMerr(PEM_F_PEM_DEF_CALLBACK, PEM_R_PROBLEMS_GETTING_PASSWORD);
60 memset(buf, 0, (unsigned int)num);
61 return -1;
62 }
63 return strlen(buf);
64 }
65
PEM_proc_type(char * buf,int type)66 void PEM_proc_type(char *buf, int type)
67 {
68 const char *str;
69 char *p = buf + strlen(buf);
70
71 if (type == PEM_TYPE_ENCRYPTED)
72 str = "ENCRYPTED";
73 else if (type == PEM_TYPE_MIC_CLEAR)
74 str = "MIC-CLEAR";
75 else if (type == PEM_TYPE_MIC_ONLY)
76 str = "MIC-ONLY";
77 else
78 str = "BAD-TYPE";
79
80 BIO_snprintf(p, PEM_BUFSIZE - (size_t)(p - buf), "Proc-Type: 4,%s\n", str);
81 }
82
PEM_dek_info(char * buf,const char * type,int len,char * str)83 void PEM_dek_info(char *buf, const char *type, int len, char *str)
84 {
85 long i;
86 char *p = buf + strlen(buf);
87 int j = PEM_BUFSIZE - (size_t)(p - buf), n;
88
89 n = BIO_snprintf(p, j, "DEK-Info: %s,", type);
90 if (n > 0) {
91 j -= n;
92 p += n;
93 for (i = 0; i < len; i++) {
94 n = BIO_snprintf(p, j, "%02X", 0xff & str[i]);
95 if (n <= 0)
96 return;
97 j -= n;
98 p += n;
99 }
100 if (j > 1)
101 strcpy(p, "\n");
102 }
103 }
104
105 #ifndef OPENSSL_NO_STDIO
PEM_ASN1_read(d2i_of_void * d2i,const char * name,FILE * fp,void ** x,pem_password_cb * cb,void * u)106 void *PEM_ASN1_read(d2i_of_void *d2i, const char *name, FILE *fp, void **x,
107 pem_password_cb *cb, void *u)
108 {
109 BIO *b;
110 void *ret;
111
112 if ((b = BIO_new(BIO_s_file())) == NULL) {
113 PEMerr(PEM_F_PEM_ASN1_READ, ERR_R_BUF_LIB);
114 return 0;
115 }
116 BIO_set_fp(b, fp, BIO_NOCLOSE);
117 ret = PEM_ASN1_read_bio(d2i, name, b, x, cb, u);
118 BIO_free(b);
119 return ret;
120 }
121 #endif
122
check_pem(const char * nm,const char * name)123 static int check_pem(const char *nm, const char *name)
124 {
125 /* Normal matching nm and name */
126 if (strcmp(nm, name) == 0)
127 return 1;
128
129 /* Make PEM_STRING_EVP_PKEY match any private key */
130
131 if (strcmp(name, PEM_STRING_EVP_PKEY) == 0) {
132 int slen;
133 const EVP_PKEY_ASN1_METHOD *ameth;
134 if (strcmp(nm, PEM_STRING_PKCS8) == 0)
135 return 1;
136 if (strcmp(nm, PEM_STRING_PKCS8INF) == 0)
137 return 1;
138 slen = pem_check_suffix(nm, "PRIVATE KEY");
139 if (slen > 0) {
140 /*
141 * NB: ENGINE implementations won't contain a deprecated old
142 * private key decode function so don't look for them.
143 */
144 ameth = EVP_PKEY_asn1_find_str(NULL, nm, slen);
145 if (ameth && ameth->old_priv_decode)
146 return 1;
147 }
148 return 0;
149 }
150
151 if (strcmp(name, PEM_STRING_PARAMETERS) == 0) {
152 int slen;
153 const EVP_PKEY_ASN1_METHOD *ameth;
154 slen = pem_check_suffix(nm, "PARAMETERS");
155 if (slen > 0) {
156 ENGINE *e;
157 ameth = EVP_PKEY_asn1_find_str(&e, nm, slen);
158 if (ameth) {
159 int r;
160 if (ameth->param_decode)
161 r = 1;
162 else
163 r = 0;
164 #ifndef OPENSSL_NO_ENGINE
165 ENGINE_finish(e);
166 #endif
167 return r;
168 }
169 }
170 return 0;
171 }
172 /* If reading DH parameters handle X9.42 DH format too */
173 if (strcmp(nm, PEM_STRING_DHXPARAMS) == 0
174 && strcmp(name, PEM_STRING_DHPARAMS) == 0)
175 return 1;
176
177 /* Permit older strings */
178
179 if (strcmp(nm, PEM_STRING_X509_OLD) == 0
180 && strcmp(name, PEM_STRING_X509) == 0)
181 return 1;
182
183 if (strcmp(nm, PEM_STRING_X509_REQ_OLD) == 0
184 && strcmp(name, PEM_STRING_X509_REQ) == 0)
185 return 1;
186
187 /* Allow normal certs to be read as trusted certs */
188 if (strcmp(nm, PEM_STRING_X509) == 0
189 && strcmp(name, PEM_STRING_X509_TRUSTED) == 0)
190 return 1;
191
192 if (strcmp(nm, PEM_STRING_X509_OLD) == 0
193 && strcmp(name, PEM_STRING_X509_TRUSTED) == 0)
194 return 1;
195
196 /* Some CAs use PKCS#7 with CERTIFICATE headers */
197 if (strcmp(nm, PEM_STRING_X509) == 0
198 && strcmp(name, PEM_STRING_PKCS7) == 0)
199 return 1;
200
201 if (strcmp(nm, PEM_STRING_PKCS7_SIGNED) == 0
202 && strcmp(name, PEM_STRING_PKCS7) == 0)
203 return 1;
204
205 #ifndef OPENSSL_NO_CMS
206 if (strcmp(nm, PEM_STRING_X509) == 0
207 && strcmp(name, PEM_STRING_CMS) == 0)
208 return 1;
209 /* Allow CMS to be read from PKCS#7 headers */
210 if (strcmp(nm, PEM_STRING_PKCS7) == 0
211 && strcmp(name, PEM_STRING_CMS) == 0)
212 return 1;
213 #endif
214
215 return 0;
216 }
217
pem_free(void * p,unsigned int flags,size_t num)218 static void pem_free(void *p, unsigned int flags, size_t num)
219 {
220 if (flags & PEM_FLAG_SECURE)
221 OPENSSL_secure_clear_free(p, num);
222 else
223 OPENSSL_free(p);
224 }
225
pem_malloc(int num,unsigned int flags)226 static void *pem_malloc(int num, unsigned int flags)
227 {
228 return (flags & PEM_FLAG_SECURE) ? OPENSSL_secure_malloc(num)
229 : OPENSSL_malloc(num);
230 }
231
pem_bytes_read_bio_flags(unsigned char ** pdata,long * plen,char ** pnm,const char * name,BIO * bp,pem_password_cb * cb,void * u,unsigned int flags)232 static int pem_bytes_read_bio_flags(unsigned char **pdata, long *plen,
233 char **pnm, const char *name, BIO *bp,
234 pem_password_cb *cb, void *u,
235 unsigned int flags)
236 {
237 EVP_CIPHER_INFO cipher;
238 char *nm = NULL, *header = NULL;
239 unsigned char *data = NULL;
240 long len = 0;
241 int ret = 0;
242
243 do {
244 pem_free(nm, flags, 0);
245 pem_free(header, flags, 0);
246 pem_free(data, flags, len);
247 if (!PEM_read_bio_ex(bp, &nm, &header, &data, &len, flags)) {
248 if (ERR_GET_REASON(ERR_peek_error()) == PEM_R_NO_START_LINE)
249 ERR_add_error_data(2, "Expecting: ", name);
250 return 0;
251 }
252 } while (!check_pem(nm, name));
253 if (!PEM_get_EVP_CIPHER_INFO(header, &cipher))
254 goto err;
255 if (!PEM_do_header(&cipher, data, &len, cb, u))
256 goto err;
257
258 *pdata = data;
259 *plen = len;
260
261 if (pnm != NULL)
262 *pnm = nm;
263
264 ret = 1;
265
266 err:
267 if (!ret || pnm == NULL)
268 pem_free(nm, flags, 0);
269 pem_free(header, flags, 0);
270 if (!ret)
271 pem_free(data, flags, len);
272 return ret;
273 }
274
PEM_bytes_read_bio(unsigned char ** pdata,long * plen,char ** pnm,const char * name,BIO * bp,pem_password_cb * cb,void * u)275 int PEM_bytes_read_bio(unsigned char **pdata, long *plen, char **pnm,
276 const char *name, BIO *bp, pem_password_cb *cb,
277 void *u) {
278 return pem_bytes_read_bio_flags(pdata, plen, pnm, name, bp, cb, u,
279 PEM_FLAG_EAY_COMPATIBLE);
280 }
281
PEM_bytes_read_bio_secmem(unsigned char ** pdata,long * plen,char ** pnm,const char * name,BIO * bp,pem_password_cb * cb,void * u)282 int PEM_bytes_read_bio_secmem(unsigned char **pdata, long *plen, char **pnm,
283 const char *name, BIO *bp, pem_password_cb *cb,
284 void *u) {
285 return pem_bytes_read_bio_flags(pdata, plen, pnm, name, bp, cb, u,
286 PEM_FLAG_SECURE | PEM_FLAG_EAY_COMPATIBLE);
287 }
288
289 #ifndef OPENSSL_NO_STDIO
PEM_ASN1_write(i2d_of_void * i2d,const char * name,FILE * fp,void * x,const EVP_CIPHER * enc,unsigned char * kstr,int klen,pem_password_cb * callback,void * u)290 int PEM_ASN1_write(i2d_of_void *i2d, const char *name, FILE *fp,
291 void *x, const EVP_CIPHER *enc, unsigned char *kstr,
292 int klen, pem_password_cb *callback, void *u)
293 {
294 BIO *b;
295 int ret;
296
297 if ((b = BIO_new(BIO_s_file())) == NULL) {
298 PEMerr(PEM_F_PEM_ASN1_WRITE, ERR_R_BUF_LIB);
299 return 0;
300 }
301 BIO_set_fp(b, fp, BIO_NOCLOSE);
302 ret = PEM_ASN1_write_bio(i2d, name, b, x, enc, kstr, klen, callback, u);
303 BIO_free(b);
304 return ret;
305 }
306 #endif
307
PEM_ASN1_write_bio(i2d_of_void * i2d,const char * name,BIO * bp,void * x,const EVP_CIPHER * enc,unsigned char * kstr,int klen,pem_password_cb * callback,void * u)308 int PEM_ASN1_write_bio(i2d_of_void *i2d, const char *name, BIO *bp,
309 void *x, const EVP_CIPHER *enc, unsigned char *kstr,
310 int klen, pem_password_cb *callback, void *u)
311 {
312 EVP_CIPHER_CTX *ctx = NULL;
313 int dsize = 0, i = 0, j = 0, ret = 0;
314 unsigned char *p, *data = NULL;
315 const char *objstr = NULL;
316 char buf[PEM_BUFSIZE];
317 unsigned char key[EVP_MAX_KEY_LENGTH];
318 unsigned char iv[EVP_MAX_IV_LENGTH];
319
320 if (enc != NULL) {
321 objstr = OBJ_nid2sn(EVP_CIPHER_nid(enc));
322 if (objstr == NULL || EVP_CIPHER_iv_length(enc) == 0
323 || EVP_CIPHER_iv_length(enc) > (int)sizeof(iv)
324 /*
325 * Check "Proc-Type: 4,Encrypted\nDEK-Info: objstr,hex-iv\n"
326 * fits into buf
327 */
328 || (strlen(objstr) + 23 + 2 * EVP_CIPHER_iv_length(enc) + 13)
329 > sizeof(buf)) {
330 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, PEM_R_UNSUPPORTED_CIPHER);
331 goto err;
332 }
333 }
334
335 if ((dsize = i2d(x, NULL)) <= 0) {
336 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, ERR_R_ASN1_LIB);
337 dsize = 0;
338 goto err;
339 }
340 /* dsize + 8 bytes are needed */
341 /* actually it needs the cipher block size extra... */
342 data = OPENSSL_malloc((unsigned int)dsize + 20);
343 if (data == NULL) {
344 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, ERR_R_MALLOC_FAILURE);
345 goto err;
346 }
347 p = data;
348 i = i2d(x, &p);
349
350 if (enc != NULL) {
351 if (kstr == NULL) {
352 if (callback == NULL)
353 klen = PEM_def_callback(buf, PEM_BUFSIZE, 1, u);
354 else
355 klen = (*callback) (buf, PEM_BUFSIZE, 1, u);
356 if (klen <= 0) {
357 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, PEM_R_READ_KEY);
358 goto err;
359 }
360 #ifdef CHARSET_EBCDIC
361 /* Convert the pass phrase from EBCDIC */
362 ebcdic2ascii(buf, buf, klen);
363 #endif
364 kstr = (unsigned char *)buf;
365 }
366 if (RAND_bytes(iv, EVP_CIPHER_iv_length(enc)) <= 0) /* Generate a salt */
367 goto err;
368 /*
369 * The 'iv' is used as the iv and as a salt. It is NOT taken from
370 * the BytesToKey function
371 */
372 if (!EVP_BytesToKey(enc, EVP_md5(), iv, kstr, klen, 1, key, NULL))
373 goto err;
374
375 if (kstr == (unsigned char *)buf)
376 OPENSSL_cleanse(buf, PEM_BUFSIZE);
377
378 buf[0] = '\0';
379 PEM_proc_type(buf, PEM_TYPE_ENCRYPTED);
380 PEM_dek_info(buf, objstr, EVP_CIPHER_iv_length(enc), (char *)iv);
381 /* k=strlen(buf); */
382
383 ret = 1;
384 if ((ctx = EVP_CIPHER_CTX_new()) == NULL
385 || !EVP_EncryptInit_ex(ctx, enc, NULL, key, iv)
386 || !EVP_EncryptUpdate(ctx, data, &j, data, i)
387 || !EVP_EncryptFinal_ex(ctx, &(data[j]), &i))
388 ret = 0;
389 if (ret == 0)
390 goto err;
391 i += j;
392 } else {
393 ret = 1;
394 buf[0] = '\0';
395 }
396 i = PEM_write_bio(bp, name, buf, data, i);
397 if (i <= 0)
398 ret = 0;
399 err:
400 OPENSSL_cleanse(key, sizeof(key));
401 OPENSSL_cleanse(iv, sizeof(iv));
402 EVP_CIPHER_CTX_free(ctx);
403 OPENSSL_cleanse(buf, PEM_BUFSIZE);
404 OPENSSL_clear_free(data, (unsigned int)dsize);
405 return ret;
406 }
407
PEM_do_header(EVP_CIPHER_INFO * cipher,unsigned char * data,long * plen,pem_password_cb * callback,void * u)408 int PEM_do_header(EVP_CIPHER_INFO *cipher, unsigned char *data, long *plen,
409 pem_password_cb *callback, void *u)
410 {
411 int ok;
412 int keylen;
413 long len = *plen;
414 int ilen = (int) len; /* EVP_DecryptUpdate etc. take int lengths */
415 EVP_CIPHER_CTX *ctx;
416 unsigned char key[EVP_MAX_KEY_LENGTH];
417 char buf[PEM_BUFSIZE];
418
419 #if LONG_MAX > INT_MAX
420 /* Check that we did not truncate the length */
421 if (len > INT_MAX) {
422 PEMerr(PEM_F_PEM_DO_HEADER, PEM_R_HEADER_TOO_LONG);
423 return 0;
424 }
425 #endif
426
427 if (cipher->cipher == NULL)
428 return 1;
429 if (callback == NULL)
430 keylen = PEM_def_callback(buf, PEM_BUFSIZE, 0, u);
431 else
432 keylen = callback(buf, PEM_BUFSIZE, 0, u);
433 if (keylen < 0) {
434 PEMerr(PEM_F_PEM_DO_HEADER, PEM_R_BAD_PASSWORD_READ);
435 return 0;
436 }
437 #ifdef CHARSET_EBCDIC
438 /* Convert the pass phrase from EBCDIC */
439 ebcdic2ascii(buf, buf, keylen);
440 #endif
441
442 if (!EVP_BytesToKey(cipher->cipher, EVP_md5(), &(cipher->iv[0]),
443 (unsigned char *)buf, keylen, 1, key, NULL))
444 return 0;
445
446 ctx = EVP_CIPHER_CTX_new();
447 if (ctx == NULL)
448 return 0;
449
450 ok = EVP_DecryptInit_ex(ctx, cipher->cipher, NULL, key, &(cipher->iv[0]));
451 if (ok)
452 ok = EVP_DecryptUpdate(ctx, data, &ilen, data, ilen);
453 if (ok) {
454 /* Squirrel away the length of data decrypted so far. */
455 *plen = ilen;
456 ok = EVP_DecryptFinal_ex(ctx, &(data[ilen]), &ilen);
457 }
458 if (ok)
459 *plen += ilen;
460 else
461 PEMerr(PEM_F_PEM_DO_HEADER, PEM_R_BAD_DECRYPT);
462
463 EVP_CIPHER_CTX_free(ctx);
464 OPENSSL_cleanse((char *)buf, sizeof(buf));
465 OPENSSL_cleanse((char *)key, sizeof(key));
466 return ok;
467 }
468
469 /*
470 * This implements a very limited PEM header parser that does not support the
471 * full grammar of rfc1421. In particular, folded headers are not supported,
472 * nor is additional whitespace.
473 *
474 * A robust implementation would make use of a library that turns the headers
475 * into a BIO from which one folded line is read at a time, and is then split
476 * into a header label and content. We would then parse the content of the
477 * headers we care about. This is overkill for just this limited use-case, but
478 * presumably we also parse rfc822-style headers for S/MIME, so a common
479 * abstraction might well be more generally useful.
480 */
PEM_get_EVP_CIPHER_INFO(char * header,EVP_CIPHER_INFO * cipher)481 int PEM_get_EVP_CIPHER_INFO(char *header, EVP_CIPHER_INFO *cipher)
482 {
483 static const char ProcType[] = "Proc-Type:";
484 static const char ENCRYPTED[] = "ENCRYPTED";
485 static const char DEKInfo[] = "DEK-Info:";
486 const EVP_CIPHER *enc = NULL;
487 int ivlen;
488 char *dekinfostart, c;
489
490 cipher->cipher = NULL;
491 memset(cipher->iv, 0, sizeof(cipher->iv));
492 if ((header == NULL) || (*header == '\0') || (*header == '\n'))
493 return 1;
494
495 if (strncmp(header, ProcType, sizeof(ProcType)-1) != 0) {
496 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_NOT_PROC_TYPE);
497 return 0;
498 }
499 header += sizeof(ProcType)-1;
500 header += strspn(header, " \t");
501
502 if (*header++ != '4' || *header++ != ',')
503 return 0;
504 header += strspn(header, " \t");
505
506 /* We expect "ENCRYPTED" followed by optional white-space + line break */
507 if (strncmp(header, ENCRYPTED, sizeof(ENCRYPTED)-1) != 0 ||
508 strspn(header+sizeof(ENCRYPTED)-1, " \t\r\n") == 0) {
509 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_NOT_ENCRYPTED);
510 return 0;
511 }
512 header += sizeof(ENCRYPTED)-1;
513 header += strspn(header, " \t\r");
514 if (*header++ != '\n') {
515 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_SHORT_HEADER);
516 return 0;
517 }
518
519 /*-
520 * https://tools.ietf.org/html/rfc1421#section-4.6.1.3
521 * We expect "DEK-Info: algo[,hex-parameters]"
522 */
523 if (strncmp(header, DEKInfo, sizeof(DEKInfo)-1) != 0) {
524 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_NOT_DEK_INFO);
525 return 0;
526 }
527 header += sizeof(DEKInfo)-1;
528 header += strspn(header, " \t");
529
530 /*
531 * DEK-INFO is a comma-separated combination of algorithm name and optional
532 * parameters.
533 */
534 dekinfostart = header;
535 header += strcspn(header, " \t,");
536 c = *header;
537 *header = '\0';
538 cipher->cipher = enc = EVP_get_cipherbyname(dekinfostart);
539 *header = c;
540 header += strspn(header, " \t");
541
542 if (enc == NULL) {
543 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_UNSUPPORTED_ENCRYPTION);
544 return 0;
545 }
546 ivlen = EVP_CIPHER_iv_length(enc);
547 if (ivlen > 0 && *header++ != ',') {
548 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_MISSING_DEK_IV);
549 return 0;
550 } else if (ivlen == 0 && *header == ',') {
551 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_UNEXPECTED_DEK_IV);
552 return 0;
553 }
554
555 if (!load_iv(&header, cipher->iv, EVP_CIPHER_iv_length(enc)))
556 return 0;
557
558 return 1;
559 }
560
load_iv(char ** fromp,unsigned char * to,int num)561 static int load_iv(char **fromp, unsigned char *to, int num)
562 {
563 int v, i;
564 char *from;
565
566 from = *fromp;
567 for (i = 0; i < num; i++)
568 to[i] = 0;
569 num *= 2;
570 for (i = 0; i < num; i++) {
571 v = OPENSSL_hexchar2int(*from);
572 if (v < 0) {
573 PEMerr(PEM_F_LOAD_IV, PEM_R_BAD_IV_CHARS);
574 return 0;
575 }
576 from++;
577 to[i / 2] |= v << (long)((!(i & 1)) * 4);
578 }
579
580 *fromp = from;
581 return 1;
582 }
583
584 #ifndef OPENSSL_NO_STDIO
PEM_write(FILE * fp,const char * name,const char * header,const unsigned char * data,long len)585 int PEM_write(FILE *fp, const char *name, const char *header,
586 const unsigned char *data, long len)
587 {
588 BIO *b;
589 int ret;
590
591 if ((b = BIO_new(BIO_s_file())) == NULL) {
592 PEMerr(PEM_F_PEM_WRITE, ERR_R_BUF_LIB);
593 return 0;
594 }
595 BIO_set_fp(b, fp, BIO_NOCLOSE);
596 ret = PEM_write_bio(b, name, header, data, len);
597 BIO_free(b);
598 return ret;
599 }
600 #endif
601
PEM_write_bio(BIO * bp,const char * name,const char * header,const unsigned char * data,long len)602 int PEM_write_bio(BIO *bp, const char *name, const char *header,
603 const unsigned char *data, long len)
604 {
605 int nlen, n, i, j, outl;
606 unsigned char *buf = NULL;
607 EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new();
608 int reason = ERR_R_BUF_LIB;
609 int retval = 0;
610
611 if (ctx == NULL) {
612 reason = ERR_R_MALLOC_FAILURE;
613 goto err;
614 }
615
616 EVP_EncodeInit(ctx);
617 nlen = strlen(name);
618
619 if ((BIO_write(bp, "-----BEGIN ", 11) != 11) ||
620 (BIO_write(bp, name, nlen) != nlen) ||
621 (BIO_write(bp, "-----\n", 6) != 6))
622 goto err;
623
624 i = strlen(header);
625 if (i > 0) {
626 if ((BIO_write(bp, header, i) != i) || (BIO_write(bp, "\n", 1) != 1))
627 goto err;
628 }
629
630 buf = OPENSSL_malloc(PEM_BUFSIZE * 8);
631 if (buf == NULL) {
632 reason = ERR_R_MALLOC_FAILURE;
633 goto err;
634 }
635
636 i = j = 0;
637 while (len > 0) {
638 n = (int)((len > (PEM_BUFSIZE * 5)) ? (PEM_BUFSIZE * 5) : len);
639 if (!EVP_EncodeUpdate(ctx, buf, &outl, &(data[j]), n))
640 goto err;
641 if ((outl) && (BIO_write(bp, (char *)buf, outl) != outl))
642 goto err;
643 i += outl;
644 len -= n;
645 j += n;
646 }
647 EVP_EncodeFinal(ctx, buf, &outl);
648 if ((outl > 0) && (BIO_write(bp, (char *)buf, outl) != outl))
649 goto err;
650 if ((BIO_write(bp, "-----END ", 9) != 9) ||
651 (BIO_write(bp, name, nlen) != nlen) ||
652 (BIO_write(bp, "-----\n", 6) != 6))
653 goto err;
654 retval = i + outl;
655
656 err:
657 if (retval == 0)
658 PEMerr(PEM_F_PEM_WRITE_BIO, reason);
659 EVP_ENCODE_CTX_free(ctx);
660 OPENSSL_clear_free(buf, PEM_BUFSIZE * 8);
661 return retval;
662 }
663
664 #ifndef OPENSSL_NO_STDIO
PEM_read(FILE * fp,char ** name,char ** header,unsigned char ** data,long * len)665 int PEM_read(FILE *fp, char **name, char **header, unsigned char **data,
666 long *len)
667 {
668 BIO *b;
669 int ret;
670
671 if ((b = BIO_new(BIO_s_file())) == NULL) {
672 PEMerr(PEM_F_PEM_READ, ERR_R_BUF_LIB);
673 return 0;
674 }
675 BIO_set_fp(b, fp, BIO_NOCLOSE);
676 ret = PEM_read_bio(b, name, header, data, len);
677 BIO_free(b);
678 return ret;
679 }
680 #endif
681
682 /* Some helpers for PEM_read_bio_ex(). */
sanitize_line(char * linebuf,int len,unsigned int flags)683 static int sanitize_line(char *linebuf, int len, unsigned int flags)
684 {
685 int i;
686
687 if (flags & PEM_FLAG_EAY_COMPATIBLE) {
688 /* Strip trailing whitespace */
689 while ((len >= 0) && (linebuf[len] <= ' '))
690 len--;
691 /* Go back to whitespace before applying uniform line ending. */
692 len++;
693 } else if (flags & PEM_FLAG_ONLY_B64) {
694 for (i = 0; i < len; ++i) {
695 if (!ossl_isbase64(linebuf[i]) || linebuf[i] == '\n'
696 || linebuf[i] == '\r')
697 break;
698 }
699 len = i;
700 } else {
701 /* EVP_DecodeBlock strips leading and trailing whitespace, so just strip
702 * control characters in-place and let everything through. */
703 for (i = 0; i < len; ++i) {
704 if (linebuf[i] == '\n' || linebuf[i] == '\r')
705 break;
706 if (ossl_iscntrl(linebuf[i]))
707 linebuf[i] = ' ';
708 }
709 len = i;
710 }
711 /* The caller allocated LINESIZE+1, so this is safe. */
712 linebuf[len++] = '\n';
713 linebuf[len] = '\0';
714 return len;
715 }
716
717 #define LINESIZE 255
718 /* Note trailing spaces for begin and end. */
719 static const char beginstr[] = "-----BEGIN ";
720 static const char endstr[] = "-----END ";
721 static const char tailstr[] = "-----\n";
722 #define BEGINLEN ((int)(sizeof(beginstr) - 1))
723 #define ENDLEN ((int)(sizeof(endstr) - 1))
724 #define TAILLEN ((int)(sizeof(tailstr) - 1))
get_name(BIO * bp,char ** name,unsigned int flags)725 static int get_name(BIO *bp, char **name, unsigned int flags)
726 {
727 char *linebuf;
728 int ret = 0;
729 int len;
730
731 /*
732 * Need to hold trailing NUL (accounted for by BIO_gets() and the newline
733 * that will be added by sanitize_line() (the extra '1').
734 */
735 linebuf = pem_malloc(LINESIZE + 1, flags);
736 if (linebuf == NULL) {
737 PEMerr(PEM_F_GET_NAME, ERR_R_MALLOC_FAILURE);
738 return 0;
739 }
740
741 do {
742 len = BIO_gets(bp, linebuf, LINESIZE);
743
744 if (len <= 0) {
745 PEMerr(PEM_F_GET_NAME, PEM_R_NO_START_LINE);
746 goto err;
747 }
748
749 /* Strip trailing garbage and standardize ending. */
750 len = sanitize_line(linebuf, len, flags & ~PEM_FLAG_ONLY_B64);
751
752 /* Allow leading empty or non-matching lines. */
753 } while (strncmp(linebuf, beginstr, BEGINLEN) != 0
754 || len < TAILLEN
755 || strncmp(linebuf + len - TAILLEN, tailstr, TAILLEN) != 0);
756 linebuf[len - TAILLEN] = '\0';
757 len = len - BEGINLEN - TAILLEN + 1;
758 *name = pem_malloc(len, flags);
759 if (*name == NULL) {
760 PEMerr(PEM_F_GET_NAME, ERR_R_MALLOC_FAILURE);
761 goto err;
762 }
763 memcpy(*name, linebuf + BEGINLEN, len);
764 ret = 1;
765
766 err:
767 pem_free(linebuf, flags, LINESIZE + 1);
768 return ret;
769 }
770
771 /* Keep track of how much of a header we've seen. */
772 enum header_status {
773 MAYBE_HEADER,
774 IN_HEADER,
775 POST_HEADER
776 };
777
778 /**
779 * Extract the optional PEM header, with details on the type of content and
780 * any encryption used on the contents, and the bulk of the data from the bio.
781 * The end of the header is marked by a blank line; if the end-of-input marker
782 * is reached prior to a blank line, there is no header.
783 *
784 * The header and data arguments are BIO** since we may have to swap them
785 * if there is no header, for efficiency.
786 *
787 * We need the name of the PEM-encoded type to verify the end string.
788 */
get_header_and_data(BIO * bp,BIO ** header,BIO ** data,char * name,unsigned int flags)789 static int get_header_and_data(BIO *bp, BIO **header, BIO **data, char *name,
790 unsigned int flags)
791 {
792 BIO *tmp = *header;
793 char *linebuf, *p;
794 int len, line, ret = 0, end = 0, prev_partial_line_read = 0, partial_line_read = 0;
795 /* 0 if not seen (yet), 1 if reading header, 2 if finished header */
796 enum header_status got_header = MAYBE_HEADER;
797 unsigned int flags_mask;
798 size_t namelen;
799
800 /* Need to hold trailing NUL (accounted for by BIO_gets() and the newline
801 * that will be added by sanitize_line() (the extra '1'). */
802 linebuf = pem_malloc(LINESIZE + 1, flags);
803 if (linebuf == NULL) {
804 PEMerr(PEM_F_GET_HEADER_AND_DATA, ERR_R_MALLOC_FAILURE);
805 return 0;
806 }
807
808 for (line = 0; ; line++) {
809 flags_mask = ~0u;
810 len = BIO_gets(bp, linebuf, LINESIZE);
811 if (len <= 0) {
812 PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE);
813 goto err;
814 }
815
816 /*
817 * Check if line has been read completely or if only part of the line
818 * has been read. Keep the previous value to ignore newlines that
819 * appear due to reading a line up until the char before the newline.
820 */
821 prev_partial_line_read = partial_line_read;
822 partial_line_read = len == LINESIZE-1 && linebuf[LINESIZE-2] != '\n';
823
824 if (got_header == MAYBE_HEADER) {
825 if (memchr(linebuf, ':', len) != NULL)
826 got_header = IN_HEADER;
827 }
828 if (!strncmp(linebuf, endstr, ENDLEN) || got_header == IN_HEADER)
829 flags_mask &= ~PEM_FLAG_ONLY_B64;
830 len = sanitize_line(linebuf, len, flags & flags_mask);
831
832 /* Check for end of header. */
833 if (linebuf[0] == '\n') {
834 /*
835 * If previous line has been read only partially this newline is a
836 * regular newline at the end of a line and not an empty line.
837 */
838 if (!prev_partial_line_read) {
839 if (got_header == POST_HEADER) {
840 /* Another blank line is an error. */
841 PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE);
842 goto err;
843 }
844 got_header = POST_HEADER;
845 tmp = *data;
846 }
847 continue;
848 }
849
850 /* Check for end of stream (which means there is no header). */
851 if (strncmp(linebuf, endstr, ENDLEN) == 0) {
852 p = linebuf + ENDLEN;
853 namelen = strlen(name);
854 if (strncmp(p, name, namelen) != 0 ||
855 strncmp(p + namelen, tailstr, TAILLEN) != 0) {
856 PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE);
857 goto err;
858 }
859 if (got_header == MAYBE_HEADER) {
860 *header = *data;
861 *data = tmp;
862 }
863 break;
864 } else if (end) {
865 /* Malformed input; short line not at end of data. */
866 PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE);
867 goto err;
868 }
869 /*
870 * Else, a line of text -- could be header or data; we don't
871 * know yet. Just pass it through.
872 */
873 if (BIO_puts(tmp, linebuf) < 0)
874 goto err;
875 /*
876 * Only encrypted files need the line length check applied.
877 */
878 if (got_header == POST_HEADER) {
879 /* 65 includes the trailing newline */
880 if (len > 65)
881 goto err;
882 if (len < 65)
883 end = 1;
884 }
885 }
886
887 ret = 1;
888 err:
889 pem_free(linebuf, flags, LINESIZE + 1);
890 return ret;
891 }
892
893 /**
894 * Read in PEM-formatted data from the given BIO.
895 *
896 * By nature of the PEM format, all content must be printable ASCII (except
897 * for line endings). Other characters are malformed input and will be rejected.
898 */
PEM_read_bio_ex(BIO * bp,char ** name_out,char ** header,unsigned char ** data,long * len_out,unsigned int flags)899 int PEM_read_bio_ex(BIO *bp, char **name_out, char **header,
900 unsigned char **data, long *len_out, unsigned int flags)
901 {
902 EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new();
903 const BIO_METHOD *bmeth;
904 BIO *headerB = NULL, *dataB = NULL;
905 char *name = NULL;
906 int len, taillen, headerlen, ret = 0;
907 BUF_MEM * buf_mem;
908
909 if (ctx == NULL) {
910 PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_MALLOC_FAILURE);
911 return 0;
912 }
913
914 *len_out = 0;
915 *name_out = *header = NULL;
916 *data = NULL;
917 if ((flags & PEM_FLAG_EAY_COMPATIBLE) && (flags & PEM_FLAG_ONLY_B64)) {
918 /* These two are mutually incompatible; bail out. */
919 PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_PASSED_INVALID_ARGUMENT);
920 goto end;
921 }
922 bmeth = (flags & PEM_FLAG_SECURE) ? BIO_s_secmem() : BIO_s_mem();
923
924 headerB = BIO_new(bmeth);
925 dataB = BIO_new(bmeth);
926 if (headerB == NULL || dataB == NULL) {
927 PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_MALLOC_FAILURE);
928 goto end;
929 }
930
931 if (!get_name(bp, &name, flags))
932 goto end;
933 if (!get_header_and_data(bp, &headerB, &dataB, name, flags))
934 goto end;
935
936 EVP_DecodeInit(ctx);
937 BIO_get_mem_ptr(dataB, &buf_mem);
938 len = buf_mem->length;
939 if (EVP_DecodeUpdate(ctx, (unsigned char*)buf_mem->data, &len,
940 (unsigned char*)buf_mem->data, len) < 0
941 || EVP_DecodeFinal(ctx, (unsigned char*)&(buf_mem->data[len]),
942 &taillen) < 0) {
943 PEMerr(PEM_F_PEM_READ_BIO_EX, PEM_R_BAD_BASE64_DECODE);
944 goto end;
945 }
946 len += taillen;
947 buf_mem->length = len;
948
949 /* There was no data in the PEM file; avoid malloc(0). */
950 if (len == 0)
951 goto end;
952 headerlen = BIO_get_mem_data(headerB, NULL);
953 *header = pem_malloc(headerlen + 1, flags);
954 *data = pem_malloc(len, flags);
955 if (*header == NULL || *data == NULL) {
956 pem_free(*header, flags, 0);
957 *header = NULL;
958 pem_free(*data, flags, 0);
959 *data = NULL;
960 goto end;
961 }
962 BIO_read(headerB, *header, headerlen);
963 (*header)[headerlen] = '\0';
964 BIO_read(dataB, *data, len);
965 *len_out = len;
966 *name_out = name;
967 name = NULL;
968 ret = 1;
969
970 end:
971 EVP_ENCODE_CTX_free(ctx);
972 pem_free(name, flags, 0);
973 BIO_free(headerB);
974 BIO_free(dataB);
975 return ret;
976 }
977
PEM_read_bio(BIO * bp,char ** name,char ** header,unsigned char ** data,long * len)978 int PEM_read_bio(BIO *bp, char **name, char **header, unsigned char **data,
979 long *len)
980 {
981 return PEM_read_bio_ex(bp, name, header, data, len, PEM_FLAG_EAY_COMPATIBLE);
982 }
983
984 /*
985 * Check pem string and return prefix length. If for example the pem_str ==
986 * "RSA PRIVATE KEY" and suffix = "PRIVATE KEY" the return value is 3 for the
987 * string "RSA".
988 */
989
pem_check_suffix(const char * pem_str,const char * suffix)990 int pem_check_suffix(const char *pem_str, const char *suffix)
991 {
992 int pem_len = strlen(pem_str);
993 int suffix_len = strlen(suffix);
994 const char *p;
995 if (suffix_len + 1 >= pem_len)
996 return 0;
997 p = pem_str + pem_len - suffix_len;
998 if (strcmp(p, suffix))
999 return 0;
1000 p--;
1001 if (*p != ' ')
1002 return 0;
1003 return p - pem_str;
1004 }
1005