1 /* crypto/pem/pem_lib.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
61 #include "internal/cryptlib.h"
62 #include <openssl/buffer.h>
63 #include <openssl/objects.h>
64 #include <openssl/evp.h>
65 #include <openssl/rand.h>
66 #include <openssl/x509.h>
67 #include <openssl/pem.h>
68 #include <openssl/pkcs12.h>
69 #include "internal/asn1_int.h"
70 #ifndef OPENSSL_NO_DES
71 # include <openssl/des.h>
73 #ifndef OPENSSL_NO_ENGINE
74 # include <openssl/engine.h>
79 static int load_iv(char **fromp, unsigned char *to, int num);
80 static int check_pem(const char *nm, const char *name);
81 int pem_check_suffix(const char *pem_str, const char *suffix);
83 int PEM_def_callback(char *buf, int num, int w, void *key)
85 #ifdef OPENSSL_NO_STDIO
87 * We should not ever call the default callback routine from windows.
89 PEMerr(PEM_F_PEM_DEF_CALLBACK, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
96 i = (i > num) ? num : i;
101 prompt = EVP_get_pw_prompt();
103 prompt = "Enter PEM pass phrase:";
106 i = EVP_read_pw_string_min(buf, MIN_LENGTH, num, prompt, w);
108 PEMerr(PEM_F_PEM_DEF_CALLBACK, PEM_R_PROBLEMS_GETTING_PASSWORD);
109 memset(buf, 0, (unsigned int)num);
113 if (j < MIN_LENGTH) {
115 "phrase is too short, needs to be at least %d chars\n",
124 void PEM_proc_type(char *buf, int type)
128 if (type == PEM_TYPE_ENCRYPTED)
130 else if (type == PEM_TYPE_MIC_CLEAR)
132 else if (type == PEM_TYPE_MIC_ONLY)
137 OPENSSL_strlcat(buf, "Proc-Type: 4,", PEM_BUFSIZE);
138 OPENSSL_strlcat(buf, str, PEM_BUFSIZE);
139 OPENSSL_strlcat(buf, "\n", PEM_BUFSIZE);
142 void PEM_dek_info(char *buf, const char *type, int len, char *str)
144 static const unsigned char map[17] = "0123456789ABCDEF";
148 OPENSSL_strlcat(buf, "DEK-Info: ", PEM_BUFSIZE);
149 OPENSSL_strlcat(buf, type, PEM_BUFSIZE);
150 OPENSSL_strlcat(buf, ",", PEM_BUFSIZE);
152 if (j + (len * 2) + 1 > PEM_BUFSIZE)
154 for (i = 0; i < len; i++) {
155 buf[j + i * 2] = map[(str[i] >> 4) & 0x0f];
156 buf[j + i * 2 + 1] = map[(str[i]) & 0x0f];
158 buf[j + i * 2] = '\n';
159 buf[j + i * 2 + 1] = '\0';
162 #ifndef OPENSSL_NO_STDIO
163 void *PEM_ASN1_read(d2i_of_void *d2i, const char *name, FILE *fp, void **x,
164 pem_password_cb *cb, void *u)
169 if ((b = BIO_new(BIO_s_file())) == NULL) {
170 PEMerr(PEM_F_PEM_ASN1_READ, ERR_R_BUF_LIB);
173 BIO_set_fp(b, fp, BIO_NOCLOSE);
174 ret = PEM_ASN1_read_bio(d2i, name, b, x, cb, u);
180 static int check_pem(const char *nm, const char *name)
182 /* Normal matching nm and name */
183 if (strcmp(nm, name) == 0)
186 /* Make PEM_STRING_EVP_PKEY match any private key */
188 if (strcmp(name, PEM_STRING_EVP_PKEY) == 0) {
190 const EVP_PKEY_ASN1_METHOD *ameth;
191 if (strcmp(nm, PEM_STRING_PKCS8) == 0)
193 if (strcmp(nm, PEM_STRING_PKCS8INF) == 0)
195 slen = pem_check_suffix(nm, "PRIVATE KEY");
198 * NB: ENGINE implementations wont contain a deprecated old
199 * private key decode function so don't look for them.
201 ameth = EVP_PKEY_asn1_find_str(NULL, nm, slen);
202 if (ameth && ameth->old_priv_decode)
208 if (strcmp(name, PEM_STRING_PARAMETERS) == 0) {
210 const EVP_PKEY_ASN1_METHOD *ameth;
211 slen = pem_check_suffix(nm, "PARAMETERS");
214 ameth = EVP_PKEY_asn1_find_str(&e, nm, slen);
217 if (ameth->param_decode)
221 #ifndef OPENSSL_NO_ENGINE
230 /* If reading DH parameters handle X9.42 DH format too */
231 if (strcmp(nm, PEM_STRING_DHXPARAMS) == 0
232 && strcmp(name, PEM_STRING_DHPARAMS) == 0)
235 /* Permit older strings */
237 if (strcmp(nm, PEM_STRING_X509_OLD) == 0
238 && strcmp(name, PEM_STRING_X509) == 0)
241 if (strcmp(nm, PEM_STRING_X509_REQ_OLD) == 0
242 && strcmp(name, PEM_STRING_X509_REQ) == 0)
245 /* Allow normal certs to be read as trusted certs */
246 if (strcmp(nm, PEM_STRING_X509) == 0
247 && strcmp(name, PEM_STRING_X509_TRUSTED) == 0)
250 if (strcmp(nm, PEM_STRING_X509_OLD) == 0
251 && strcmp(name, PEM_STRING_X509_TRUSTED) == 0)
254 /* Some CAs use PKCS#7 with CERTIFICATE headers */
255 if (strcmp(nm, PEM_STRING_X509) == 0
256 && strcmp(name, PEM_STRING_PKCS7) == 0)
259 if (strcmp(nm, PEM_STRING_PKCS7_SIGNED) == 0
260 && strcmp(name, PEM_STRING_PKCS7) == 0)
263 #ifndef OPENSSL_NO_CMS
264 if (strcmp(nm, PEM_STRING_X509) == 0
265 && strcmp(name, PEM_STRING_CMS) == 0)
267 /* Allow CMS to be read from PKCS#7 headers */
268 if (strcmp(nm, PEM_STRING_PKCS7) == 0
269 && strcmp(name, PEM_STRING_CMS) == 0)
276 int PEM_bytes_read_bio(unsigned char **pdata, long *plen, char **pnm,
277 const char *name, BIO *bp, pem_password_cb *cb,
280 EVP_CIPHER_INFO cipher;
281 char *nm = NULL, *header = NULL;
282 unsigned char *data = NULL;
287 if (!PEM_read_bio(bp, &nm, &header, &data, &len)) {
288 if (ERR_GET_REASON(ERR_peek_error()) == PEM_R_NO_START_LINE)
289 ERR_add_error_data(2, "Expecting: ", name);
292 if (check_pem(nm, name))
295 OPENSSL_free(header);
298 if (!PEM_get_EVP_CIPHER_INFO(header, &cipher))
300 if (!PEM_do_header(&cipher, data, &len, cb, u))
314 OPENSSL_free(header);
320 #ifndef OPENSSL_NO_STDIO
321 int PEM_ASN1_write(i2d_of_void *i2d, const char *name, FILE *fp,
322 void *x, const EVP_CIPHER *enc, unsigned char *kstr,
323 int klen, pem_password_cb *callback, void *u)
328 if ((b = BIO_new(BIO_s_file())) == NULL) {
329 PEMerr(PEM_F_PEM_ASN1_WRITE, ERR_R_BUF_LIB);
332 BIO_set_fp(b, fp, BIO_NOCLOSE);
333 ret = PEM_ASN1_write_bio(i2d, name, b, x, enc, kstr, klen, callback, u);
339 int PEM_ASN1_write_bio(i2d_of_void *i2d, const char *name, BIO *bp,
340 void *x, const EVP_CIPHER *enc, unsigned char *kstr,
341 int klen, pem_password_cb *callback, void *u)
344 int dsize = 0, i = 0, j = 0, ret = 0;
345 unsigned char *p, *data = NULL;
346 const char *objstr = NULL;
347 char buf[PEM_BUFSIZE];
348 unsigned char key[EVP_MAX_KEY_LENGTH];
349 unsigned char iv[EVP_MAX_IV_LENGTH];
352 objstr = OBJ_nid2sn(EVP_CIPHER_nid(enc));
353 if (objstr == NULL) {
354 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, PEM_R_UNSUPPORTED_CIPHER);
359 if ((dsize = i2d(x, NULL)) < 0) {
360 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, ERR_R_ASN1_LIB);
364 /* dzise + 8 bytes are needed */
365 /* actually it needs the cipher block size extra... */
366 data = OPENSSL_malloc((unsigned int)dsize + 20);
368 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, ERR_R_MALLOC_FAILURE);
376 if (callback == NULL)
377 klen = PEM_def_callback(buf, PEM_BUFSIZE, 1, u);
379 klen = (*callback) (buf, PEM_BUFSIZE, 1, u);
381 PEMerr(PEM_F_PEM_ASN1_WRITE_BIO, PEM_R_READ_KEY);
384 #ifdef CHARSET_EBCDIC
385 /* Convert the pass phrase from EBCDIC */
386 ebcdic2ascii(buf, buf, klen);
388 kstr = (unsigned char *)buf;
390 RAND_add(data, i, 0); /* put in the RSA key. */
391 OPENSSL_assert(enc->iv_len <= (int)sizeof(iv));
392 if (RAND_bytes(iv, enc->iv_len) <= 0) /* Generate a salt */
395 * The 'iv' is used as the iv and as a salt. It is NOT taken from
396 * the BytesToKey function
398 if (!EVP_BytesToKey(enc, EVP_md5(), iv, kstr, klen, 1, key, NULL))
401 if (kstr == (unsigned char *)buf)
402 OPENSSL_cleanse(buf, PEM_BUFSIZE);
404 OPENSSL_assert(strlen(objstr) + 23 + 2 * enc->iv_len + 13 <=
408 PEM_proc_type(buf, PEM_TYPE_ENCRYPTED);
409 PEM_dek_info(buf, objstr, enc->iv_len, (char *)iv);
412 EVP_CIPHER_CTX_init(&ctx);
414 if (!EVP_EncryptInit_ex(&ctx, enc, NULL, key, iv)
415 || !EVP_EncryptUpdate(&ctx, data, &j, data, i)
416 || !EVP_EncryptFinal_ex(&ctx, &(data[j]), &i))
418 EVP_CIPHER_CTX_cleanup(&ctx);
426 i = PEM_write_bio(bp, name, buf, data, i);
430 OPENSSL_cleanse(key, sizeof(key));
431 OPENSSL_cleanse(iv, sizeof(iv));
432 OPENSSL_cleanse((char *)&ctx, sizeof(ctx));
433 OPENSSL_cleanse(buf, PEM_BUFSIZE);
434 OPENSSL_clear_free(data, (unsigned int)dsize);
438 int PEM_do_header(EVP_CIPHER_INFO *cipher, unsigned char *data, long *plen,
439 pem_password_cb *callback, void *u)
441 int i = 0, j, o, klen;
444 unsigned char key[EVP_MAX_KEY_LENGTH];
445 char buf[PEM_BUFSIZE];
449 if (cipher->cipher == NULL)
451 if (callback == NULL)
452 klen = PEM_def_callback(buf, PEM_BUFSIZE, 0, u);
454 klen = callback(buf, PEM_BUFSIZE, 0, u);
456 PEMerr(PEM_F_PEM_DO_HEADER, PEM_R_BAD_PASSWORD_READ);
459 #ifdef CHARSET_EBCDIC
460 /* Convert the pass phrase from EBCDIC */
461 ebcdic2ascii(buf, buf, klen);
464 if (!EVP_BytesToKey(cipher->cipher, EVP_md5(), &(cipher->iv[0]),
465 (unsigned char *)buf, klen, 1, key, NULL))
469 EVP_CIPHER_CTX_init(&ctx);
470 o = EVP_DecryptInit_ex(&ctx, cipher->cipher, NULL, key, &(cipher->iv[0]));
472 o = EVP_DecryptUpdate(&ctx, data, &i, data, j);
474 o = EVP_DecryptFinal_ex(&ctx, &(data[i]), &j);
475 EVP_CIPHER_CTX_cleanup(&ctx);
476 OPENSSL_cleanse((char *)buf, sizeof(buf));
477 OPENSSL_cleanse((char *)key, sizeof(key));
481 PEMerr(PEM_F_PEM_DO_HEADER, PEM_R_BAD_DECRYPT);
488 int PEM_get_EVP_CIPHER_INFO(char *header, EVP_CIPHER_INFO *cipher)
490 const EVP_CIPHER *enc = NULL;
492 char **header_pp = &header;
494 cipher->cipher = NULL;
495 if ((header == NULL) || (*header == '\0') || (*header == '\n'))
497 if (strncmp(header, "Proc-Type: ", 11) != 0) {
498 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_NOT_PROC_TYPE);
508 if (strncmp(header, "ENCRYPTED", 9) != 0) {
509 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_NOT_ENCRYPTED);
512 for (; (*header != '\n') && (*header != '\0'); header++) ;
513 if (*header == '\0') {
514 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_SHORT_HEADER);
518 if (strncmp(header, "DEK-Info: ", 10) != 0) {
519 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_NOT_DEK_INFO);
527 #ifndef CHARSET_EBCDIC
528 if (!(((c >= 'A') && (c <= 'Z')) || (c == '-') ||
529 ((c >= '0') && (c <= '9'))))
532 if (!(isupper(c) || (c == '-') || isdigit(c)))
538 cipher->cipher = enc = EVP_get_cipherbyname(p);
543 PEMerr(PEM_F_PEM_GET_EVP_CIPHER_INFO, PEM_R_UNSUPPORTED_ENCRYPTION);
546 if (!load_iv(header_pp, &(cipher->iv[0]), enc->iv_len))
552 static int load_iv(char **fromp, unsigned char *to, int num)
558 for (i = 0; i < num; i++)
561 for (i = 0; i < num; i++) {
562 if ((*from >= '0') && (*from <= '9'))
564 else if ((*from >= 'A') && (*from <= 'F'))
565 v = *from - 'A' + 10;
566 else if ((*from >= 'a') && (*from <= 'f'))
567 v = *from - 'a' + 10;
569 PEMerr(PEM_F_LOAD_IV, PEM_R_BAD_IV_CHARS);
573 to[i / 2] |= v << (long)((!(i & 1)) * 4);
580 #ifndef OPENSSL_NO_STDIO
581 int PEM_write(FILE *fp, const char *name, const char *header,
582 const unsigned char *data, long len)
587 if ((b = BIO_new(BIO_s_file())) == NULL) {
588 PEMerr(PEM_F_PEM_WRITE, ERR_R_BUF_LIB);
591 BIO_set_fp(b, fp, BIO_NOCLOSE);
592 ret = PEM_write_bio(b, name, header, data, len);
598 int PEM_write_bio(BIO *bp, const char *name, const char *header,
599 const unsigned char *data, long len)
601 int nlen, n, i, j, outl;
602 unsigned char *buf = NULL;
603 EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new();
604 int reason = ERR_R_BUF_LIB;
607 reason = ERR_R_MALLOC_FAILURE;
614 if ((BIO_write(bp, "-----BEGIN ", 11) != 11) ||
615 (BIO_write(bp, name, nlen) != nlen) ||
616 (BIO_write(bp, "-----\n", 6) != 6))
621 if ((BIO_write(bp, header, i) != i) || (BIO_write(bp, "\n", 1) != 1))
625 buf = OPENSSL_malloc(PEM_BUFSIZE * 8);
627 reason = ERR_R_MALLOC_FAILURE;
633 n = (int)((len > (PEM_BUFSIZE * 5)) ? (PEM_BUFSIZE * 5) : len);
634 EVP_EncodeUpdate(ctx, buf, &outl, &(data[j]), n);
635 if ((outl) && (BIO_write(bp, (char *)buf, outl) != outl))
641 EVP_EncodeFinal(ctx, buf, &outl);
642 if ((outl > 0) && (BIO_write(bp, (char *)buf, outl) != outl))
644 if ((BIO_write(bp, "-----END ", 9) != 9) ||
645 (BIO_write(bp, name, nlen) != nlen) ||
646 (BIO_write(bp, "-----\n", 6) != 6))
648 OPENSSL_clear_free(buf, PEM_BUFSIZE * 8);
649 EVP_ENCODE_CTX_free(ctx);
652 OPENSSL_clear_free(buf, PEM_BUFSIZE * 8);
653 EVP_ENCODE_CTX_free(ctx);
654 PEMerr(PEM_F_PEM_WRITE_BIO, reason);
658 #ifndef OPENSSL_NO_STDIO
659 int PEM_read(FILE *fp, char **name, char **header, unsigned char **data,
665 if ((b = BIO_new(BIO_s_file())) == NULL) {
666 PEMerr(PEM_F_PEM_READ, ERR_R_BUF_LIB);
669 BIO_set_fp(b, fp, BIO_NOCLOSE);
670 ret = PEM_read_bio(b, name, header, data, len);
676 int PEM_read_bio(BIO *bp, char **name, char **header, unsigned char **data,
679 EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new();
680 int end = 0, i, k, bl = 0, hl = 0, nohead = 0;
684 BUF_MEM *dataB, *tmpB;
687 PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE);
691 nameB = BUF_MEM_new();
692 headerB = BUF_MEM_new();
693 dataB = BUF_MEM_new();
694 if ((nameB == NULL) || (headerB == NULL) || (dataB == NULL)) {
700 i = BIO_gets(bp, buf, 254);
703 PEMerr(PEM_F_PEM_READ_BIO, PEM_R_NO_START_LINE);
707 while ((i >= 0) && (buf[i] <= ' '))
712 if (strncmp(buf, "-----BEGIN ", 11) == 0) {
713 i = strlen(&(buf[11]));
715 if (strncmp(&(buf[11 + i - 6]), "-----\n", 6) != 0)
717 if (!BUF_MEM_grow(nameB, i + 9)) {
718 PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE);
721 memcpy(nameB->data, &(buf[11]), i - 6);
722 nameB->data[i - 6] = '\0';
727 if (!BUF_MEM_grow(headerB, 256)) {
728 PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE);
731 headerB->data[0] = '\0';
733 i = BIO_gets(bp, buf, 254);
737 while ((i >= 0) && (buf[i] <= ' '))
744 if (!BUF_MEM_grow(headerB, hl + i + 9)) {
745 PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE);
748 if (strncmp(buf, "-----END ", 9) == 0) {
752 memcpy(&(headerB->data[hl]), buf, i);
753 headerB->data[hl + i] = '\0';
758 if (!BUF_MEM_grow(dataB, 1024)) {
759 PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE);
762 dataB->data[0] = '\0';
765 i = BIO_gets(bp, buf, 254);
769 while ((i >= 0) && (buf[i] <= ' '))
776 if (strncmp(buf, "-----END ", 9) == 0)
780 if (!BUF_MEM_grow_clean(dataB, i + bl + 9)) {
781 PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE);
784 memcpy(&(dataB->data[bl]), buf, i);
785 dataB->data[bl + i] = '\0';
789 i = BIO_gets(bp, buf, 254);
793 while ((i >= 0) && (buf[i] <= ' '))
807 i = strlen(nameB->data);
808 if ((strncmp(buf, "-----END ", 9) != 0) ||
809 (strncmp(nameB->data, &(buf[9]), i) != 0) ||
810 (strncmp(&(buf[9 + i]), "-----\n", 6) != 0)) {
811 PEMerr(PEM_F_PEM_READ_BIO, PEM_R_BAD_END_LINE);
816 i = EVP_DecodeUpdate(ctx,
817 (unsigned char *)dataB->data, &bl,
818 (unsigned char *)dataB->data, bl);
820 PEMerr(PEM_F_PEM_READ_BIO, PEM_R_BAD_BASE64_DECODE);
823 i = EVP_DecodeFinal(ctx, (unsigned char *)&(dataB->data[bl]), &k);
825 PEMerr(PEM_F_PEM_READ_BIO, PEM_R_BAD_BASE64_DECODE);
833 *header = headerB->data;
834 *data = (unsigned char *)dataB->data;
837 OPENSSL_free(headerB);
839 EVP_ENCODE_CTX_free(ctx);
843 BUF_MEM_free(headerB);
845 EVP_ENCODE_CTX_free(ctx);
850 * Check pem string and return prefix length. If for example the pem_str ==
851 * "RSA PRIVATE KEY" and suffix = "PRIVATE KEY" the return value is 3 for the
855 int pem_check_suffix(const char *pem_str, const char *suffix)
857 int pem_len = strlen(pem_str);
858 int suffix_len = strlen(suffix);
860 if (suffix_len + 1 >= pem_len)
862 p = pem_str + pem_len - suffix_len;
863 if (strcmp(p, suffix))