1=pod 2 3=head1 NAME 4 5pem_password_cb, 6PEM_read_bio_PrivateKey_ex, PEM_read_bio_PrivateKey, 7PEM_read_PrivateKey_ex, PEM_read_PrivateKey, 8PEM_write_bio_PrivateKey_ex, PEM_write_bio_PrivateKey, 9PEM_write_bio_PrivateKey_traditional, 10PEM_write_PrivateKey_ex, PEM_write_PrivateKey, 11PEM_write_bio_PKCS8PrivateKey, PEM_write_PKCS8PrivateKey, 12PEM_write_bio_PKCS8PrivateKey_nid, PEM_write_PKCS8PrivateKey_nid, 13PEM_read_bio_PUBKEY_ex, PEM_read_bio_PUBKEY, 14PEM_read_PUBKEY_ex, PEM_read_PUBKEY, 15PEM_write_bio_PUBKEY_ex, PEM_write_bio_PUBKEY, 16PEM_write_PUBKEY_ex, PEM_write_PUBKEY, 17PEM_read_bio_RSAPrivateKey, PEM_read_RSAPrivateKey, 18PEM_write_bio_RSAPrivateKey, PEM_write_RSAPrivateKey, 19PEM_read_bio_RSAPublicKey, PEM_read_RSAPublicKey, PEM_write_bio_RSAPublicKey, 20PEM_write_RSAPublicKey, PEM_read_bio_RSA_PUBKEY, PEM_read_RSA_PUBKEY, 21PEM_write_bio_RSA_PUBKEY, PEM_write_RSA_PUBKEY, PEM_read_bio_DSAPrivateKey, 22PEM_read_DSAPrivateKey, PEM_write_bio_DSAPrivateKey, PEM_write_DSAPrivateKey, 23PEM_read_bio_DSA_PUBKEY, PEM_read_DSA_PUBKEY, PEM_write_bio_DSA_PUBKEY, 24PEM_write_DSA_PUBKEY, PEM_read_bio_Parameters_ex, PEM_read_bio_Parameters, 25PEM_write_bio_Parameters, PEM_read_bio_DSAparams, PEM_read_DSAparams, 26PEM_write_bio_DSAparams, PEM_write_DSAparams, PEM_read_bio_DHparams, 27PEM_read_DHparams, PEM_write_bio_DHparams, PEM_write_DHparams, 28PEM_read_bio_X509, PEM_read_X509, PEM_write_bio_X509, PEM_write_X509, 29PEM_read_bio_X509_AUX, PEM_read_X509_AUX, PEM_write_bio_X509_AUX, 30PEM_write_X509_AUX, PEM_read_bio_X509_REQ, PEM_read_X509_REQ, 31PEM_write_bio_X509_REQ, PEM_write_X509_REQ, PEM_write_bio_X509_REQ_NEW, 32PEM_write_X509_REQ_NEW, PEM_read_bio_X509_CRL, PEM_read_X509_CRL, 33PEM_write_bio_X509_CRL, PEM_write_X509_CRL, PEM_read_bio_PKCS7, PEM_read_PKCS7, 34PEM_write_bio_PKCS7, PEM_write_PKCS7 - PEM routines 35 36=head1 SYNOPSIS 37 38 #include <openssl/pem.h> 39 40 typedef int pem_password_cb(char *buf, int size, int rwflag, void *u); 41 42 EVP_PKEY *PEM_read_bio_PrivateKey_ex(BIO *bp, EVP_PKEY **x, 43 pem_password_cb *cb, void *u, 44 OSSL_LIB_CTX *libctx, const char *propq); 45 EVP_PKEY *PEM_read_bio_PrivateKey(BIO *bp, EVP_PKEY **x, 46 pem_password_cb *cb, void *u); 47 EVP_PKEY *PEM_read_PrivateKey_ex(FILE *fp, EVP_PKEY **x, pem_password_cb *cb, 48 void *u, OSSL_LIB_CTX *libctx, 49 const char *propq); 50 EVP_PKEY *PEM_read_PrivateKey(FILE *fp, EVP_PKEY **x, 51 pem_password_cb *cb, void *u); 52 int PEM_write_bio_PrivateKey_ex(BIO *bp, const EVP_PKEY *x, 53 const EVP_CIPHER *enc, 54 unsigned char *kstr, int klen, 55 pem_password_cb *cb, void *u, 56 OSSL_LIB_CTX *libctx, const char *propq); 57 int PEM_write_bio_PrivateKey(BIO *bp, const EVP_PKEY *x, const EVP_CIPHER *enc, 58 unsigned char *kstr, int klen, 59 pem_password_cb *cb, void *u); 60 int PEM_write_bio_PrivateKey_traditional(BIO *bp, EVP_PKEY *x, 61 const EVP_CIPHER *enc, 62 unsigned char *kstr, int klen, 63 pem_password_cb *cb, void *u); 64 int PEM_write_PrivateKey_ex(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc, 65 unsigned char *kstr, int klen, 66 pem_password_cb *cb, void *u, 67 OSSL_LIB_CTX *libctx, const char *propq); 68 int PEM_write_PrivateKey(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc, 69 unsigned char *kstr, int klen, 70 pem_password_cb *cb, void *u); 71 int PEM_write_bio_PKCS8PrivateKey(BIO *bp, EVP_PKEY *x, const EVP_CIPHER *enc, 72 char *kstr, int klen, 73 pem_password_cb *cb, void *u); 74 int PEM_write_PKCS8PrivateKey(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc, 75 char *kstr, int klen, 76 pem_password_cb *cb, void *u); 77 int PEM_write_bio_PKCS8PrivateKey_nid(BIO *bp, const EVP_PKEY *x, int nid, 78 char *kstr, int klen, 79 pem_password_cb *cb, void *u); 80 int PEM_write_PKCS8PrivateKey_nid(FILE *fp, const EVP_PKEY *x, int nid, 81 char *kstr, int klen, 82 pem_password_cb *cb, void *u); 83 84 EVP_PKEY *PEM_read_bio_PUBKEY_ex(BIO *bp, EVP_PKEY **x, 85 pem_password_cb *cb, void *u, 86 OSSL_LIB_CTX *libctx, const char *propq); 87 EVP_PKEY *PEM_read_bio_PUBKEY(BIO *bp, EVP_PKEY **x, 88 pem_password_cb *cb, void *u); 89 EVP_PKEY *PEM_read_PUBKEY_ex(FILE *fp, EVP_PKEY **x, 90 pem_password_cb *cb, void *u, 91 OSSL_LIB_CTX *libctx, const char *propq); 92 EVP_PKEY *PEM_read_PUBKEY(FILE *fp, EVP_PKEY **x, 93 pem_password_cb *cb, void *u); 94 int PEM_write_bio_PUBKEY_ex(BIO *bp, EVP_PKEY *x, 95 OSSL_LIB_CTX *libctx, const char *propq); 96 int PEM_write_bio_PUBKEY(BIO *bp, EVP_PKEY *x); 97 int PEM_write_PUBKEY_ex(FILE *fp, EVP_PKEY *x, 98 OSSL_LIB_CTX *libctx, const char *propq); 99 int PEM_write_PUBKEY(FILE *fp, EVP_PKEY *x); 100 101 EVP_PKEY *PEM_read_bio_Parameters_ex(BIO *bp, EVP_PKEY **x, 102 OSSL_LIB_CTX *libctx, const char *propq); 103 EVP_PKEY *PEM_read_bio_Parameters(BIO *bp, EVP_PKEY **x); 104 int PEM_write_bio_Parameters(BIO *bp, const EVP_PKEY *x); 105 106 X509 *PEM_read_bio_X509(BIO *bp, X509 **x, pem_password_cb *cb, void *u); 107 X509 *PEM_read_X509(FILE *fp, X509 **x, pem_password_cb *cb, void *u); 108 int PEM_write_bio_X509(BIO *bp, X509 *x); 109 int PEM_write_X509(FILE *fp, X509 *x); 110 111 X509 *PEM_read_bio_X509_AUX(BIO *bp, X509 **x, pem_password_cb *cb, void *u); 112 X509 *PEM_read_X509_AUX(FILE *fp, X509 **x, pem_password_cb *cb, void *u); 113 int PEM_write_bio_X509_AUX(BIO *bp, X509 *x); 114 int PEM_write_X509_AUX(FILE *fp, X509 *x); 115 116 X509_REQ *PEM_read_bio_X509_REQ(BIO *bp, X509_REQ **x, 117 pem_password_cb *cb, void *u); 118 X509_REQ *PEM_read_X509_REQ(FILE *fp, X509_REQ **x, 119 pem_password_cb *cb, void *u); 120 int PEM_write_bio_X509_REQ(BIO *bp, X509_REQ *x); 121 int PEM_write_X509_REQ(FILE *fp, X509_REQ *x); 122 int PEM_write_bio_X509_REQ_NEW(BIO *bp, X509_REQ *x); 123 int PEM_write_X509_REQ_NEW(FILE *fp, X509_REQ *x); 124 125 X509_CRL *PEM_read_bio_X509_CRL(BIO *bp, X509_CRL **x, 126 pem_password_cb *cb, void *u); 127 X509_CRL *PEM_read_X509_CRL(FILE *fp, X509_CRL **x, 128 pem_password_cb *cb, void *u); 129 int PEM_write_bio_X509_CRL(BIO *bp, X509_CRL *x); 130 int PEM_write_X509_CRL(FILE *fp, X509_CRL *x); 131 132 PKCS7 *PEM_read_bio_PKCS7(BIO *bp, PKCS7 **x, pem_password_cb *cb, void *u); 133 PKCS7 *PEM_read_PKCS7(FILE *fp, PKCS7 **x, pem_password_cb *cb, void *u); 134 int PEM_write_bio_PKCS7(BIO *bp, PKCS7 *x); 135 int PEM_write_PKCS7(FILE *fp, PKCS7 *x); 136 137The following functions have been deprecated since OpenSSL 3.0, and can be 138hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, 139see L<openssl_user_macros(7)>: 140 141 RSA *PEM_read_bio_RSAPrivateKey(BIO *bp, RSA **x, 142 pem_password_cb *cb, void *u); 143 RSA *PEM_read_RSAPrivateKey(FILE *fp, RSA **x, 144 pem_password_cb *cb, void *u); 145 int PEM_write_bio_RSAPrivateKey(BIO *bp, RSA *x, const EVP_CIPHER *enc, 146 unsigned char *kstr, int klen, 147 pem_password_cb *cb, void *u); 148 int PEM_write_RSAPrivateKey(FILE *fp, RSA *x, const EVP_CIPHER *enc, 149 unsigned char *kstr, int klen, 150 pem_password_cb *cb, void *u); 151 152 RSA *PEM_read_bio_RSAPublicKey(BIO *bp, RSA **x, 153 pem_password_cb *cb, void *u); 154 RSA *PEM_read_RSAPublicKey(FILE *fp, RSA **x, 155 pem_password_cb *cb, void *u); 156 int PEM_write_bio_RSAPublicKey(BIO *bp, RSA *x); 157 int PEM_write_RSAPublicKey(FILE *fp, RSA *x); 158 159 RSA *PEM_read_bio_RSA_PUBKEY(BIO *bp, RSA **x, 160 pem_password_cb *cb, void *u); 161 RSA *PEM_read_RSA_PUBKEY(FILE *fp, RSA **x, 162 pem_password_cb *cb, void *u); 163 int PEM_write_bio_RSA_PUBKEY(BIO *bp, RSA *x); 164 int PEM_write_RSA_PUBKEY(FILE *fp, RSA *x); 165 166 DSA *PEM_read_bio_DSAPrivateKey(BIO *bp, DSA **x, 167 pem_password_cb *cb, void *u); 168 DSA *PEM_read_DSAPrivateKey(FILE *fp, DSA **x, 169 pem_password_cb *cb, void *u); 170 int PEM_write_bio_DSAPrivateKey(BIO *bp, DSA *x, const EVP_CIPHER *enc, 171 unsigned char *kstr, int klen, 172 pem_password_cb *cb, void *u); 173 int PEM_write_DSAPrivateKey(FILE *fp, DSA *x, const EVP_CIPHER *enc, 174 unsigned char *kstr, int klen, 175 pem_password_cb *cb, void *u); 176 177 DSA *PEM_read_bio_DSA_PUBKEY(BIO *bp, DSA **x, 178 pem_password_cb *cb, void *u); 179 DSA *PEM_read_DSA_PUBKEY(FILE *fp, DSA **x, 180 pem_password_cb *cb, void *u); 181 int PEM_write_bio_DSA_PUBKEY(BIO *bp, DSA *x); 182 int PEM_write_DSA_PUBKEY(FILE *fp, DSA *x); 183 DSA *PEM_read_bio_DSAparams(BIO *bp, DSA **x, pem_password_cb *cb, void *u); 184 DSA *PEM_read_DSAparams(FILE *fp, DSA **x, pem_password_cb *cb, void *u); 185 int PEM_write_bio_DSAparams(BIO *bp, DSA *x); 186 int PEM_write_DSAparams(FILE *fp, DSA *x); 187 188 DH *PEM_read_bio_DHparams(BIO *bp, DH **x, pem_password_cb *cb, void *u); 189 DH *PEM_read_DHparams(FILE *fp, DH **x, pem_password_cb *cb, void *u); 190 int PEM_write_bio_DHparams(BIO *bp, DH *x); 191 int PEM_write_DHparams(FILE *fp, DH *x); 192 193=head1 DESCRIPTION 194 195All of the functions described on this page that have a I<TYPE> of B<DH>, B<DSA> 196and B<RSA> are deprecated. Applications should use L<OSSL_ENCODER_to_bio(3)> and 197L<OSSL_DECODER_from_bio(3)> instead. 198 199The PEM functions read or write structures in PEM format. In 200this sense PEM format is simply base64 encoded data surrounded 201by header lines. 202 203For more details about the meaning of arguments see the 204B<PEM FUNCTION ARGUMENTS> section. 205 206Each operation has four functions associated with it. For 207brevity the term "B<I<TYPE>> functions" will be used below to collectively 208refer to the B<PEM_read_bio_I<TYPE>>(), B<PEM_read_I<TYPE>>(), 209B<PEM_write_bio_I<TYPE>>(), and B<PEM_write_I<TYPE>>() functions. 210 211Some operations have additional variants that take a library context I<libctx> 212and a property query string I<propq>. The B<X509>, B<X509_REQ> and B<X509_CRL> 213objects may have an associated library context or property query string but 214there are no variants of these functions that take a library context or property 215query string parameter. In this case it is possible to set the appropriate 216library context or property query string by creating an empty B<X509>, 217B<X509_REQ> or B<X509_CRL> object using L<X509_new_ex(3)>, L<X509_REQ_new_ex(3)> 218or L<X509_CRL_new_ex(3)> respectively. Then pass the empty object as a parameter 219to the relevant PEM function. See the L</EXAMPLES> section below. 220 221The B<PrivateKey> functions read or write a private key in PEM format using 222an EVP_PKEY structure. The write routines use PKCS#8 private key format and are 223equivalent to PEM_write_bio_PKCS8PrivateKey(). The read functions transparently 224handle traditional and PKCS#8 format encrypted and unencrypted keys. 225 226PEM_write_bio_PrivateKey_traditional() writes out a private key in the 227"traditional" format with a simple private key marker and should only 228be used for compatibility with legacy programs. 229 230PEM_write_bio_PKCS8PrivateKey() and PEM_write_PKCS8PrivateKey() write a private 231key in an EVP_PKEY structure in PKCS#8 EncryptedPrivateKeyInfo format using 232PKCS#5 v2.0 password based encryption algorithms. The I<cipher> argument 233specifies the encryption algorithm to use: unlike some other PEM routines the 234encryption is applied at the PKCS#8 level and not in the PEM headers. If 235I<cipher> is NULL then no encryption is used and a PKCS#8 PrivateKeyInfo 236structure is used instead. 237 238PEM_write_bio_PKCS8PrivateKey_nid() and PEM_write_PKCS8PrivateKey_nid() 239also write out a private key as a PKCS#8 EncryptedPrivateKeyInfo however 240it uses PKCS#5 v1.5 or PKCS#12 encryption algorithms instead. The algorithm 241to use is specified in the I<nid> parameter and should be the NID of the 242corresponding OBJECT IDENTIFIER (see NOTES section). 243 244The B<PUBKEY> functions process a public key using an EVP_PKEY 245structure. The public key is encoded as a SubjectPublicKeyInfo 246structure. 247 248The B<RSAPrivateKey> functions process an RSA private key using an 249RSA structure. The write routines uses traditional format. The read 250routines handles the same formats as the B<PrivateKey> 251functions but an error occurs if the private key is not RSA. 252 253The B<RSAPublicKey> functions process an RSA public key using an 254RSA structure. The public key is encoded using a PKCS#1 RSAPublicKey 255structure. 256 257The B<RSA_PUBKEY> functions also process an RSA public key using 258an RSA structure. However, the public key is encoded using a 259SubjectPublicKeyInfo structure and an error occurs if the public 260key is not RSA. 261 262The B<DSAPrivateKey> functions process a DSA private key using a 263DSA structure. The write routines uses traditional format. The read 264routines handles the same formats as the B<PrivateKey> 265functions but an error occurs if the private key is not DSA. 266 267The B<DSA_PUBKEY> functions process a DSA public key using 268a DSA structure. The public key is encoded using a 269SubjectPublicKeyInfo structure and an error occurs if the public 270key is not DSA. 271 272The B<Parameters> functions read or write key parameters in PEM format using 273an EVP_PKEY structure. The encoding depends on the type of key; for DSA key 274parameters, it will be a Dss-Parms structure as defined in RFC2459, and for DH 275key parameters, it will be a PKCS#3 DHparameter structure. I<These functions 276only exist for the B<BIO> type>. 277 278The B<DSAparams> functions process DSA parameters using a DSA 279structure. The parameters are encoded using a Dss-Parms structure 280as defined in RFC2459. 281 282The B<DHparams> functions process DH parameters using a DH 283structure. The parameters are encoded using a PKCS#3 DHparameter 284structure. 285 286The B<X509> functions process an X509 certificate using an X509 287structure. They will also process a trusted X509 certificate but 288any trust settings are discarded. 289 290The B<X509_AUX> functions process a trusted X509 certificate using 291an X509 structure. 292 293The B<X509_REQ> and B<X509_REQ_NEW> functions process a PKCS#10 294certificate request using an X509_REQ structure. The B<X509_REQ> 295write functions use B<CERTIFICATE REQUEST> in the header whereas 296the B<X509_REQ_NEW> functions use B<NEW CERTIFICATE REQUEST> 297(as required by some CAs). The B<X509_REQ> read functions will 298handle either form so there are no B<X509_REQ_NEW> read functions. 299 300The B<X509_CRL> functions process an X509 CRL using an X509_CRL 301structure. 302 303The B<PKCS7> functions process a PKCS#7 ContentInfo using a PKCS7 304structure. 305 306=head1 PEM FUNCTION ARGUMENTS 307 308The PEM functions have many common arguments. 309 310The I<bp> BIO parameter (if present) specifies the BIO to read from 311or write to. 312 313The I<fp> FILE parameter (if present) specifies the FILE pointer to 314read from or write to. 315 316The PEM read functions all take an argument I<B<TYPE> **x> and return 317a I<B<TYPE> *> pointer. Where I<B<TYPE>> is whatever structure the function 318uses. If I<x> is NULL then the parameter is ignored. If I<x> is not 319NULL but I<*x> is NULL then the structure returned will be written 320to I<*x>. If neither I<x> nor I<*x> is NULL then an attempt is made 321to reuse the structure at I<*x> (but see BUGS and EXAMPLES sections). 322Irrespective of the value of I<x> a pointer to the structure is always 323returned (or NULL if an error occurred). 324 325The PEM functions which write private keys take an I<enc> parameter 326which specifies the encryption algorithm to use, encryption is done 327at the PEM level. If this parameter is set to NULL then the private 328key is written in unencrypted form. 329 330The I<cb> argument is the callback to use when querying for the pass 331phrase used for encrypted PEM structures (normally only private keys). 332 333For the PEM write routines if the I<kstr> parameter is not NULL then 334I<klen> bytes at I<kstr> are used as the passphrase and I<cb> is 335ignored. 336 337If the I<cb> parameters is set to NULL and the I<u> parameter is not 338NULL then the I<u> parameter is interpreted as a NUL terminated string 339to use as the passphrase. If both I<cb> and I<u> are NULL then the 340default callback routine is used which will typically prompt for the 341passphrase on the current terminal with echoing turned off. 342 343The default passphrase callback is sometimes inappropriate (for example 344in a GUI application) so an alternative can be supplied. The callback 345routine has the following form: 346 347 int cb(char *buf, int size, int rwflag, void *u); 348 349I<buf> is the buffer to write the passphrase to. I<size> is the maximum 350length of the passphrase (i.e. the size of buf). I<rwflag> is a flag 351which is set to 0 when reading and 1 when writing. A typical routine 352will ask the user to verify the passphrase (for example by prompting 353for it twice) if I<rwflag> is 1. The I<u> parameter has the same 354value as the I<u> parameter passed to the PEM routine. It allows 355arbitrary data to be passed to the callback by the application 356(for example a window handle in a GUI application). The callback 357I<must> return the number of characters in the passphrase or -1 if 358an error occurred. The passphrase can be arbitrary data; in the case where it 359is a string, it is not NUL terminated. See the L</EXAMPLES> section below. 360 361Some implementations may need to use cryptographic algorithms during their 362operation. If this is the case and I<libctx> and I<propq> parameters have been 363passed then any algorithm fetches will use that library context and property 364query string. Otherwise the default library context and property query string 365will be used. 366 367=head1 NOTES 368 369The PEM reading functions will skip any extraneous content or PEM data of 370a different type than they expect. This allows for example having a certificate 371(or multiple certificates) and a key in the PEM format in a single file. 372 373The old B<PrivateKey> write routines are retained for compatibility. 374New applications should write private keys using the 375PEM_write_bio_PKCS8PrivateKey() or PEM_write_PKCS8PrivateKey() routines 376because they are more secure (they use an iteration count of 2048 whereas 377the traditional routines use a count of 1) unless compatibility with older 378versions of OpenSSL is important. 379 380The B<PrivateKey> read routines can be used in all applications because 381they handle all formats transparently. 382 383A frequent cause of problems is attempting to use the PEM routines like 384this: 385 386 X509 *x; 387 388 PEM_read_bio_X509(bp, &x, 0, NULL); 389 390this is a bug because an attempt will be made to reuse the data at I<x> 391which is an uninitialised pointer. 392 393These functions make no assumption regarding the pass phrase received from the 394password callback. 395It will simply be treated as a byte sequence. 396 397=head1 PEM ENCRYPTION FORMAT 398 399These old B<PrivateKey> routines use a non standard technique for encryption. 400 401The private key (or other data) takes the following form: 402 403 -----BEGIN RSA PRIVATE KEY----- 404 Proc-Type: 4,ENCRYPTED 405 DEK-Info: DES-EDE3-CBC,3F17F5316E2BAC89 406 407 ...base64 encoded data... 408 -----END RSA PRIVATE KEY----- 409 410The line beginning with I<Proc-Type> contains the version and the 411protection on the encapsulated data. The line beginning I<DEK-Info> 412contains two comma separated values: the encryption algorithm name as 413used by EVP_get_cipherbyname() and an initialization vector used by the 414cipher encoded as a set of hexadecimal digits. After those two lines is 415the base64-encoded encrypted data. 416 417The encryption key is derived using EVP_BytesToKey(). The cipher's 418initialization vector is passed to EVP_BytesToKey() as the I<salt> 419parameter. Internally, B<PKCS5_SALT_LEN> bytes of the salt are used 420(regardless of the size of the initialization vector). The user's 421password is passed to EVP_BytesToKey() using the I<data> and I<datal> 422parameters. Finally, the library uses an iteration count of 1 for 423EVP_BytesToKey(). 424 425The I<key> derived by EVP_BytesToKey() along with the original initialization 426vector is then used to decrypt the encrypted data. The I<iv> produced by 427EVP_BytesToKey() is not utilized or needed, and NULL should be passed to 428the function. 429 430The pseudo code to derive the key would look similar to: 431 432 EVP_CIPHER* cipher = EVP_des_ede3_cbc(); 433 EVP_MD* md = EVP_md5(); 434 435 unsigned int nkey = EVP_CIPHER_get_key_length(cipher); 436 unsigned int niv = EVP_CIPHER_get_iv_length(cipher); 437 unsigned char key[nkey]; 438 unsigned char iv[niv]; 439 440 memcpy(iv, HexToBin("3F17F5316E2BAC89"), niv); 441 rc = EVP_BytesToKey(cipher, md, iv /*salt*/, pword, plen, 1, key, NULL /*iv*/); 442 if (rc != nkey) 443 /* Error */ 444 445 /* On success, use key and iv to initialize the cipher */ 446 447=head1 BUGS 448 449The PEM read routines in some versions of OpenSSL will not correctly reuse 450an existing structure. Therefore, the following: 451 452 PEM_read_bio_X509(bp, &x, 0, NULL); 453 454where I<x> already contains a valid certificate, may not work, whereas: 455 456 X509_free(x); 457 x = PEM_read_bio_X509(bp, NULL, 0, NULL); 458 459is guaranteed to work. It is always acceptable for I<x> to contain a newly 460allocated, empty B<X509> object (for example allocated via L<X509_new_ex(3)>). 461 462=head1 RETURN VALUES 463 464The read routines return either a pointer to the structure read or NULL 465if an error occurred. 466 467The write routines return 1 for success or 0 for failure. 468 469=head1 EXAMPLES 470 471Although the PEM routines take several arguments in almost all applications 472most of them are set to 0 or NULL. 473 474To read a certificate with a library context in PEM format from a BIO: 475 476 X509 *x = X509_new_ex(libctx, NULL); 477 478 if (x == NULL) 479 /* Error */ 480 481 if (PEM_read_bio_X509(bp, &x, 0, NULL) == NULL) 482 /* Error */ 483 484Read a certificate in PEM format from a BIO: 485 486 X509 *x; 487 488 x = PEM_read_bio_X509(bp, NULL, 0, NULL); 489 if (x == NULL) 490 /* Error */ 491 492Alternative method: 493 494 X509 *x = NULL; 495 496 if (!PEM_read_bio_X509(bp, &x, 0, NULL)) 497 /* Error */ 498 499Write a certificate to a BIO: 500 501 if (!PEM_write_bio_X509(bp, x)) 502 /* Error */ 503 504Write a private key (using traditional format) to a BIO using 505triple DES encryption, the pass phrase is prompted for: 506 507 if (!PEM_write_bio_PrivateKey(bp, key, EVP_des_ede3_cbc(), NULL, 0, 0, NULL)) 508 /* Error */ 509 510Write a private key (using PKCS#8 format) to a BIO using triple 511DES encryption, using the pass phrase "hello": 512 513 if (!PEM_write_bio_PKCS8PrivateKey(bp, key, EVP_des_ede3_cbc(), 514 NULL, 0, 0, "hello")) 515 /* Error */ 516 517Read a private key from a BIO using a pass phrase callback: 518 519 key = PEM_read_bio_PrivateKey(bp, NULL, pass_cb, "My Private Key"); 520 if (key == NULL) 521 /* Error */ 522 523Skeleton pass phrase callback: 524 525 int pass_cb(char *buf, int size, int rwflag, void *u) 526 { 527 528 /* We'd probably do something else if 'rwflag' is 1 */ 529 printf("Enter pass phrase for \"%s\"\n", (char *)u); 530 531 /* get pass phrase, length 'len' into 'tmp' */ 532 char *tmp = "hello"; 533 if (tmp == NULL) /* An error occurred */ 534 return -1; 535 536 size_t len = strlen(tmp); 537 538 if (len > size) 539 len = size; 540 memcpy(buf, tmp, len); 541 return len; 542 } 543 544=head1 SEE ALSO 545 546L<EVP_EncryptInit(3)>, L<EVP_BytesToKey(3)>, 547L<passphrase-encoding(7)> 548 549=head1 HISTORY 550 551The old Netscape certificate sequences were no longer documented 552in OpenSSL 1.1.0; applications should use the PKCS7 standard instead 553as they will be formally deprecated in a future releases. 554 555PEM_read_bio_PrivateKey_ex(), PEM_read_PrivateKey_ex(), 556PEM_read_bio_PUBKEY_ex(), PEM_read_PUBKEY_ex() and 557PEM_read_bio_Parameters_ex() were introduced in OpenSSL 3.0. 558 559The functions PEM_read_bio_RSAPrivateKey(), PEM_read_RSAPrivateKey(), 560PEM_write_bio_RSAPrivateKey(), PEM_write_RSAPrivateKey(), 561PEM_read_bio_RSAPublicKey(), PEM_read_RSAPublicKey(), 562PEM_write_bio_RSAPublicKey(), PEM_write_RSAPublicKey(), 563PEM_read_bio_RSA_PUBKEY(), PEM_read_RSA_PUBKEY(), 564PEM_write_bio_RSA_PUBKEY(), PEM_write_RSA_PUBKEY(), 565PEM_read_bio_DSAPrivateKey(), PEM_read_DSAPrivateKey(), 566PEM_write_bio_DSAPrivateKey(), PEM_write_DSAPrivateKey(), 567PEM_read_bio_DSA_PUBKEY(), PEM_read_DSA_PUBKEY(), 568PEM_write_bio_DSA_PUBKEY(), PEM_write_DSA_PUBKEY(); 569PEM_read_bio_DSAparams(), PEM_read_DSAparams(), 570PEM_write_bio_DSAparams(), PEM_write_DSAparams(), 571PEM_read_bio_DHparams(), PEM_read_DHparams(), 572PEM_write_bio_DHparams() and PEM_write_DHparams() were deprecated in 3.0. 573 574 575=head1 COPYRIGHT 576 577Copyright 2001-2022 The OpenSSL Project Authors. All Rights Reserved. 578 579Licensed under the Apache License 2.0 (the "License"). You may not use 580this file except in compliance with the License. You can obtain a copy 581in the file LICENSE in the source distribution or at 582L<https://www.openssl.org/source/license.html>. 583 584=cut 585