← Back
Editing: PEM_write_bio_DSA_PUBKEY.3
.\" Automatically generated by Pod::Man 4.11 (Pod::Simple 3.35) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2). .\" Fear. Run. Save yourself. No user-serviceable parts. . \" fudge factors for nroff and troff .if n \{\ . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] \fP .\} .if t \{\ . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff .if n \{\ . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} .if t \{\ . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' .ds 8 \h'\*(#H'\(*b\h'-\*(#H' .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] .ds ae a\h'-(\w'a'u*4/10)'e .ds Ae A\h'-(\w'A'u*4/10)'E . \" corrections for vroff .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' . \" for low resolution devices (crt and lpr) .if \n(.H>23 .if \n(.V>19 \ \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} .rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "pem 3" .TH pem 3 "2019-12-20" "1.0.2u" "OpenSSL" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" PEM, PEM_read_bio_PrivateKey, PEM_read_PrivateKey, PEM_write_bio_PrivateKey, PEM_write_PrivateKey, PEM_write_bio_PKCS8PrivateKey, PEM_write_PKCS8PrivateKey, PEM_write_bio_PKCS8PrivateKey_nid, PEM_write_PKCS8PrivateKey_nid, PEM_read_bio_PUBKEY, PEM_read_PUBKEY, PEM_write_bio_PUBKEY, PEM_write_PUBKEY, PEM_read_bio_RSAPrivateKey, PEM_read_RSAPrivateKey, PEM_write_bio_RSAPrivateKey, PEM_write_RSAPrivateKey, PEM_read_bio_RSAPublicKey, PEM_read_RSAPublicKey, PEM_write_bio_RSAPublicKey, PEM_write_RSAPublicKey, PEM_read_bio_RSA_PUBKEY, PEM_read_RSA_PUBKEY, PEM_write_bio_RSA_PUBKEY, PEM_write_RSA_PUBKEY, PEM_read_bio_DSAPrivateKey, PEM_read_DSAPrivateKey, PEM_write_bio_DSAPrivateKey, PEM_write_DSAPrivateKey, PEM_read_bio_DSA_PUBKEY, PEM_read_DSA_PUBKEY, PEM_write_bio_DSA_PUBKEY, PEM_write_DSA_PUBKEY, PEM_read_bio_DSAparams, PEM_read_DSAparams, PEM_write_bio_DSAparams, PEM_write_DSAparams, PEM_read_bio_DHparams, PEM_read_DHparams, PEM_write_bio_DHparams, PEM_write_DHparams, PEM_read_bio_X509, PEM_read_X509, PEM_write_bio_X509, PEM_write_X509, PEM_read_bio_X509_AUX, PEM_read_X509_AUX, PEM_write_bio_X509_AUX, PEM_write_X509_AUX, PEM_read_bio_X509_REQ, PEM_read_X509_REQ, PEM_write_bio_X509_REQ, PEM_write_X509_REQ, PEM_write_bio_X509_REQ_NEW, PEM_write_X509_REQ_NEW, PEM_read_bio_X509_CRL, PEM_read_X509_CRL, PEM_write_bio_X509_CRL, PEM_write_X509_CRL, PEM_read_bio_PKCS7, PEM_read_PKCS7, PEM_write_bio_PKCS7, PEM_write_PKCS7, PEM_read_bio_NETSCAPE_CERT_SEQUENCE, PEM_read_NETSCAPE_CERT_SEQUENCE, PEM_write_bio_NETSCAPE_CERT_SEQUENCE, PEM_write_NETSCAPE_CERT_SEQUENCE \- PEM routines .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #include <openssl/pem.h> \& \& EVP_PKEY *PEM_read_bio_PrivateKey(BIO *bp, EVP_PKEY **x, \& pem_password_cb *cb, void *u); \& \& EVP_PKEY *PEM_read_PrivateKey(FILE *fp, EVP_PKEY **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_PrivateKey(BIO *bp, EVP_PKEY *x, const EVP_CIPHER *enc, \& unsigned char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_PrivateKey(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc, \& unsigned char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_PKCS8PrivateKey(BIO *bp, EVP_PKEY *x, const EVP_CIPHER *enc, \& char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_PKCS8PrivateKey(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc, \& char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_PKCS8PrivateKey_nid(BIO *bp, EVP_PKEY *x, int nid, \& char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_PKCS8PrivateKey_nid(FILE *fp, EVP_PKEY *x, int nid, \& char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& EVP_PKEY *PEM_read_bio_PUBKEY(BIO *bp, EVP_PKEY **x, \& pem_password_cb *cb, void *u); \& \& EVP_PKEY *PEM_read_PUBKEY(FILE *fp, EVP_PKEY **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_PUBKEY(BIO *bp, EVP_PKEY *x); \& int PEM_write_PUBKEY(FILE *fp, EVP_PKEY *x); \& \& RSA *PEM_read_bio_RSAPrivateKey(BIO *bp, RSA **x, \& pem_password_cb *cb, void *u); \& \& RSA *PEM_read_RSAPrivateKey(FILE *fp, RSA **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_RSAPrivateKey(BIO *bp, RSA *x, const EVP_CIPHER *enc, \& unsigned char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_RSAPrivateKey(FILE *fp, RSA *x, const EVP_CIPHER *enc, \& unsigned char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& RSA *PEM_read_bio_RSAPublicKey(BIO *bp, RSA **x, \& pem_password_cb *cb, void *u); \& \& RSA *PEM_read_RSAPublicKey(FILE *fp, RSA **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_RSAPublicKey(BIO *bp, RSA *x); \& \& int PEM_write_RSAPublicKey(FILE *fp, RSA *x); \& \& RSA *PEM_read_bio_RSA_PUBKEY(BIO *bp, RSA **x, \& pem_password_cb *cb, void *u); \& \& RSA *PEM_read_RSA_PUBKEY(FILE *fp, RSA **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_RSA_PUBKEY(BIO *bp, RSA *x); \& \& int PEM_write_RSA_PUBKEY(FILE *fp, RSA *x); \& \& DSA *PEM_read_bio_DSAPrivateKey(BIO *bp, DSA **x, \& pem_password_cb *cb, void *u); \& \& DSA *PEM_read_DSAPrivateKey(FILE *fp, DSA **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_DSAPrivateKey(BIO *bp, DSA *x, const EVP_CIPHER *enc, \& unsigned char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& int PEM_write_DSAPrivateKey(FILE *fp, DSA *x, const EVP_CIPHER *enc, \& unsigned char *kstr, int klen, \& pem_password_cb *cb, void *u); \& \& DSA *PEM_read_bio_DSA_PUBKEY(BIO *bp, DSA **x, \& pem_password_cb *cb, void *u); \& \& DSA *PEM_read_DSA_PUBKEY(FILE *fp, DSA **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_DSA_PUBKEY(BIO *bp, DSA *x); \& \& int PEM_write_DSA_PUBKEY(FILE *fp, DSA *x); \& \& DSA *PEM_read_bio_DSAparams(BIO *bp, DSA **x, pem_password_cb *cb, void *u); \& \& DSA *PEM_read_DSAparams(FILE *fp, DSA **x, pem_password_cb *cb, void *u); \& \& int PEM_write_bio_DSAparams(BIO *bp, DSA *x); \& \& int PEM_write_DSAparams(FILE *fp, DSA *x); \& \& DH *PEM_read_bio_DHparams(BIO *bp, DH **x, pem_password_cb *cb, void *u); \& \& DH *PEM_read_DHparams(FILE *fp, DH **x, pem_password_cb *cb, void *u); \& \& int PEM_write_bio_DHparams(BIO *bp, DH *x); \& \& int PEM_write_DHparams(FILE *fp, DH *x); \& \& X509 *PEM_read_bio_X509(BIO *bp, X509 **x, pem_password_cb *cb, void *u); \& \& X509 *PEM_read_X509(FILE *fp, X509 **x, pem_password_cb *cb, void *u); \& \& int PEM_write_bio_X509(BIO *bp, X509 *x); \& \& int PEM_write_X509(FILE *fp, X509 *x); \& \& X509 *PEM_read_bio_X509_AUX(BIO *bp, X509 **x, pem_password_cb *cb, void *u); \& \& X509 *PEM_read_X509_AUX(FILE *fp, X509 **x, pem_password_cb *cb, void *u); \& \& int PEM_write_bio_X509_AUX(BIO *bp, X509 *x); \& \& int PEM_write_X509_AUX(FILE *fp, X509 *x); \& \& X509_REQ *PEM_read_bio_X509_REQ(BIO *bp, X509_REQ **x, \& pem_password_cb *cb, void *u); \& \& X509_REQ *PEM_read_X509_REQ(FILE *fp, X509_REQ **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_X509_REQ(BIO *bp, X509_REQ *x); \& \& int PEM_write_X509_REQ(FILE *fp, X509_REQ *x); \& \& int PEM_write_bio_X509_REQ_NEW(BIO *bp, X509_REQ *x); \& \& int PEM_write_X509_REQ_NEW(FILE *fp, X509_REQ *x); \& \& X509_CRL *PEM_read_bio_X509_CRL(BIO *bp, X509_CRL **x, \& pem_password_cb *cb, void *u); \& X509_CRL *PEM_read_X509_CRL(FILE *fp, X509_CRL **x, \& pem_password_cb *cb, void *u); \& int PEM_write_bio_X509_CRL(BIO *bp, X509_CRL *x); \& int PEM_write_X509_CRL(FILE *fp, X509_CRL *x); \& \& PKCS7 *PEM_read_bio_PKCS7(BIO *bp, PKCS7 **x, pem_password_cb *cb, void *u); \& \& PKCS7 *PEM_read_PKCS7(FILE *fp, PKCS7 **x, pem_password_cb *cb, void *u); \& \& int PEM_write_bio_PKCS7(BIO *bp, PKCS7 *x); \& \& int PEM_write_PKCS7(FILE *fp, PKCS7 *x); \& \& NETSCAPE_CERT_SEQUENCE *PEM_read_bio_NETSCAPE_CERT_SEQUENCE(BIO *bp, \& NETSCAPE_CERT_SEQUENCE **x, \& pem_password_cb *cb, void *u); \& \& NETSCAPE_CERT_SEQUENCE *PEM_read_NETSCAPE_CERT_SEQUENCE(FILE *fp, \& NETSCAPE_CERT_SEQUENCE **x, \& pem_password_cb *cb, void *u); \& \& int PEM_write_bio_NETSCAPE_CERT_SEQUENCE(BIO *bp, NETSCAPE_CERT_SEQUENCE *x); \& \& int PEM_write_NETSCAPE_CERT_SEQUENCE(FILE *fp, NETSCAPE_CERT_SEQUENCE *x); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" The \s-1PEM\s0 functions read or write structures in \s-1PEM\s0 format. In this sense \s-1PEM\s0 format is simply base64 encoded data surrounded by header lines. .PP For more details about the meaning of arguments see the \&\fB\s-1PEM FUNCTION ARGUMENTS\s0\fR section. .PP Each operation has four functions associated with it. For clarity the term "\fBfoobar\fR functions" will be used to collectively refer to the \fBPEM_read_bio_foobar()\fR, \fBPEM_read_foobar()\fR, \&\fBPEM_write_bio_foobar()\fR and \fBPEM_write_foobar()\fR functions. .PP The \fBPrivateKey\fR functions read or write a private key in \&\s-1PEM\s0 format using an \s-1EVP_PKEY\s0 structure. The write routines use \&\*(L"traditional\*(R" private key format and can handle both \s-1RSA\s0 and \s-1DSA\s0 private keys. The read functions can additionally transparently handle PKCS#8 format encrypted and unencrypted keys too. .PP \&\fBPEM_write_bio_PKCS8PrivateKey()\fR and \fBPEM_write_PKCS8PrivateKey()\fR write a private key in an \s-1EVP_PKEY\s0 structure in PKCS#8 EncryptedPrivateKeyInfo format using PKCS#5 v2.0 password based encryption algorithms. The \fBcipher\fR argument specifies the encryption algorithm to use: unlike all other \s-1PEM\s0 routines the encryption is applied at the PKCS#8 level and not in the \s-1PEM\s0 headers. If \fBcipher\fR is \s-1NULL\s0 then no encryption is used and a PKCS#8 PrivateKeyInfo structure is used instead. .PP \&\fBPEM_write_bio_PKCS8PrivateKey_nid()\fR and \fBPEM_write_PKCS8PrivateKey_nid()\fR also write out a private key as a PKCS#8 EncryptedPrivateKeyInfo however it uses PKCS#5 v1.5 or PKCS#12 encryption algorithms instead. The algorithm to use is specified in the \fBnid\fR parameter and should be the \s-1NID\s0 of the corresponding \s-1OBJECT IDENTIFIER\s0 (see \s-1NOTES\s0 section). .PP The \fB\s-1PUBKEY\s0\fR functions process a public key using an \s-1EVP_PKEY\s0 structure. The public key is encoded as a SubjectPublicKeyInfo structure. .PP The \fBRSAPrivateKey\fR functions process an \s-1RSA\s0 private key using an \&\s-1RSA\s0 structure. It handles the same formats as the \fBPrivateKey\fR functions but an error occurs if the private key is not \s-1RSA.\s0 .PP The \fBRSAPublicKey\fR functions process an \s-1RSA\s0 public key using an \&\s-1RSA\s0 structure. The public key is encoded using a PKCS#1 RSAPublicKey structure. .PP The \fB\s-1RSA_PUBKEY\s0\fR functions also process an \s-1RSA\s0 public key using an \s-1RSA\s0 structure. However the public key is encoded using a SubjectPublicKeyInfo structure and an error occurs if the public key is not \s-1RSA.\s0 .PP The \fBDSAPrivateKey\fR functions process a \s-1DSA\s0 private key using a \&\s-1DSA\s0 structure. It handles the same formats as the \fBPrivateKey\fR functions but an error occurs if the private key is not \s-1DSA.\s0 .PP The \fB\s-1DSA_PUBKEY\s0\fR functions process a \s-1DSA\s0 public key using a \s-1DSA\s0 structure. The public key is encoded using a SubjectPublicKeyInfo structure and an error occurs if the public key is not \s-1DSA.\s0 .PP The \fBDSAparams\fR functions process \s-1DSA\s0 parameters using a \s-1DSA\s0 structure. The parameters are encoded using a Dss-Parms structure as defined in \s-1RFC2459.\s0 .PP The \fBDHparams\fR functions process \s-1DH\s0 parameters using a \s-1DH\s0 structure. The parameters are encoded using a PKCS#3 DHparameter structure. .PP The \fBX509\fR functions process an X509 certificate using an X509 structure. They will also process a trusted X509 certificate but any trust settings are discarded. .PP The \fBX509_AUX\fR functions process a trusted X509 certificate using an X509 structure. .PP The \fBX509_REQ\fR and \fBX509_REQ_NEW\fR functions process a PKCS#10 certificate request using an X509_REQ structure. The \fBX509_REQ\fR write functions use \fB\s-1CERTIFICATE REQUEST\s0\fR in the header whereas the \fBX509_REQ_NEW\fR functions use \fB\s-1NEW CERTIFICATE REQUEST\s0\fR (as required by some CAs). The \fBX509_REQ\fR read functions will handle either form so there are no \fBX509_REQ_NEW\fR read functions. .PP The \fBX509_CRL\fR functions process an X509 \s-1CRL\s0 using an X509_CRL structure. .PP The \fB\s-1PKCS7\s0\fR functions process a PKCS#7 ContentInfo using a \s-1PKCS7\s0 structure. .PP The \fB\s-1NETSCAPE_CERT_SEQUENCE\s0\fR functions process a Netscape Certificate Sequence using a \s-1NETSCAPE_CERT_SEQUENCE\s0 structure. .SH "PEM FUNCTION ARGUMENTS" .IX Header "PEM FUNCTION ARGUMENTS" The \s-1PEM\s0 functions have many common arguments. .PP The \fBbp\fR \s-1BIO\s0 parameter (if present) specifies the \s-1BIO\s0 to read from or write to. .PP The \fBfp\fR \s-1FILE\s0 parameter (if present) specifies the \s-1FILE\s0 pointer to read from or write to. .PP The \s-1PEM\s0 read functions all take an argument \fB\s-1TYPE\s0 **x\fR and return a \fB\s-1TYPE\s0 *\fR pointer. Where \fB\s-1TYPE\s0\fR is whatever structure the function uses. If \fBx\fR is \s-1NULL\s0 then the parameter is ignored. If \fBx\fR is not \&\s-1NULL\s0 but \fB*x\fR is \s-1NULL\s0 then the structure returned will be written to \fB*x\fR. If neither \fBx\fR nor \fB*x\fR is \s-1NULL\s0 then an attempt is made to reuse the structure at \fB*x\fR (but see \s-1BUGS\s0 and \s-1EXAMPLES\s0 sections). Irrespective of the value of \fBx\fR a pointer to the structure is always returned (or \s-1NULL\s0 if an error occurred). .PP The \s-1PEM\s0 functions which write private keys take an \fBenc\fR parameter which specifies the encryption algorithm to use, encryption is done at the \s-1PEM\s0 level. If this parameter is set to \s-1NULL\s0 then the private key is written in unencrypted form. .PP The \fBcb\fR argument is the callback to use when querying for the pass phrase used for encrypted \s-1PEM\s0 structures (normally only private keys). .PP For the \s-1PEM\s0 write routines if the \fBkstr\fR parameter is not \s-1NULL\s0 then \&\fBklen\fR bytes at \fBkstr\fR are used as the passphrase and \fBcb\fR is ignored. .PP If the \fBcb\fR parameters is set to \s-1NULL\s0 and the \fBu\fR parameter is not \&\s-1NULL\s0 then the \fBu\fR parameter is interpreted as a null terminated string to use as the passphrase. If both \fBcb\fR and \fBu\fR are \s-1NULL\s0 then the default callback routine is used which will typically prompt for the passphrase on the current terminal with echoing turned off. .PP The default passphrase callback is sometimes inappropriate (for example in a \s-1GUI\s0 application) so an alternative can be supplied. The callback routine has the following form: .PP .Vb 1 \& int cb(char *buf, int size, int rwflag, void *u); .Ve .PP \&\fBbuf\fR is the buffer to write the passphrase to. \fBsize\fR is the maximum length of the passphrase (i.e. the size of buf). \fBrwflag\fR is a flag which is set to 0 when reading and 1 when writing. A typical routine will ask the user to verify the passphrase (for example by prompting for it twice) if \fBrwflag\fR is 1. The \fBu\fR parameter has the same value as the \fBu\fR parameter passed to the \s-1PEM\s0 routine. It allows arbitrary data to be passed to the callback by the application (for example a window handle in a \s-1GUI\s0 application). The callback \&\fBmust\fR return the number of characters in the passphrase or \-1 if an error occurred. .SH "EXAMPLES" .IX Header "EXAMPLES" Although the \s-1PEM\s0 routines take several arguments in almost all applications most of them are set to 0 or \s-1NULL.\s0 .PP Read a certificate in \s-1PEM\s0 format from a \s-1BIO:\s0 .PP .Vb 5 \& X509 *x; \& x = PEM_read_bio_X509(bp, NULL, 0, NULL); \& if (x == NULL) { \& /* Error */ \& } .Ve .PP Alternative method: .PP .Vb 4 \& X509 *x = NULL; \& if (!PEM_read_bio_X509(bp, &x, 0, NULL)) { \& /* Error */ \& } .Ve .PP Write a certificate to a \s-1BIO:\s0 .PP .Vb 3 \& if (!PEM_write_bio_X509(bp, x)) { \& /* Error */ \& } .Ve .PP Write an unencrypted private key to a \s-1FILE\s0 pointer: .PP .Vb 3 \& if (!PEM_write_PrivateKey(fp, key, NULL, NULL, 0, 0, NULL)) { \& /* Error */ \& } .Ve .PP Write a private key (using traditional format) to a \s-1BIO\s0 using triple \s-1DES\s0 encryption, the pass phrase is prompted for: .PP .Vb 3 \& if (!PEM_write_bio_PrivateKey(bp, key, EVP_des_ede3_cbc(), NULL, 0, 0, NULL)) { \& /* Error */ \& } .Ve .PP Write a private key (using PKCS#8 format) to a \s-1BIO\s0 using triple \&\s-1DES\s0 encryption, using the pass phrase \*(L"hello\*(R": .PP .Vb 3 \& if (!PEM_write_bio_PKCS8PrivateKey(bp, key, EVP_des_ede3_cbc(), NULL, 0, 0, "hello")) { \& /* Error */ \& } .Ve .PP Read a private key from a \s-1BIO\s0 using the pass phrase \*(L"hello\*(R": .PP .Vb 4 \& key = PEM_read_bio_PrivateKey(bp, NULL, 0, "hello"); \& if (key == NULL) { \& /* Error */ \& } .Ve .PP Read a private key from a \s-1BIO\s0 using a pass phrase callback: .PP .Vb 4 \& key = PEM_read_bio_PrivateKey(bp, NULL, pass_cb, "My Private Key"); \& if (key == NULL) { \& /* Error */ \& } .Ve .PP Skeleton pass phrase callback: .PP .Vb 2 \& int pass_cb(char *buf, int size, int rwflag, void *u) \& { \& \& /* We\*(Aqd probably do something else if \*(Aqrwflag\*(Aq is 1 */ \& printf("Enter pass phrase for \e"%s\e"\en", u); \& \& /* get pass phrase, length \*(Aqlen\*(Aq into \*(Aqtmp\*(Aq */ \& char *tmp = "hello"; \& if (tmp == NULL) /* An error occurred */ \& return \-1; \& \& size_t len = strlen(tmp); \& \& if (len > size) \& len = size; \& memcpy(buf, tmp, len); \& return len; \& } .Ve .SH "NOTES" .IX Header "NOTES" The old \fBPrivateKey\fR write routines are retained for compatibility. New applications should write private keys using the \&\fBPEM_write_bio_PKCS8PrivateKey()\fR or \fBPEM_write_PKCS8PrivateKey()\fR routines because they are more secure (they use an iteration count of 2048 whereas the traditional routines use a count of 1) unless compatibility with older versions of OpenSSL is important. .PP The \fBPrivateKey\fR read routines can be used in all applications because they handle all formats transparently. .PP A frequent cause of problems is attempting to use the \s-1PEM\s0 routines like this: .PP .Vb 2 \& X509 *x; \& PEM_read_bio_X509(bp, &x, 0, NULL); .Ve .PP this is a bug because an attempt will be made to reuse the data at \fBx\fR which is an uninitialised pointer. .SH "PEM ENCRYPTION FORMAT" .IX Header "PEM ENCRYPTION FORMAT" This old \fBPrivateKey\fR routines use a non standard technique for encryption. .PP The private key (or other data) takes the following form: .PP .Vb 3 \& \-\-\-\-\-BEGIN RSA PRIVATE KEY\-\-\-\-\- \& Proc\-Type: 4,ENCRYPTED \& DEK\-Info: DES\-EDE3\-CBC,3F17F5316E2BAC89 \& \& ...base64 encoded data... \& \-\-\-\-\-END RSA PRIVATE KEY\-\-\-\-\- .Ve .PP The line beginning DEK-Info contains two comma separated pieces of information: the encryption algorithm name as used by \fBEVP_get_cipherbyname()\fR and an 8 byte \fBsalt\fR encoded as a set of hexadecimal digits. .PP After this is the base64 encoded encrypted data. .PP The encryption key is determined using \fBEVP_BytesToKey()\fR, using \fBsalt\fR and an iteration count of 1. The \s-1IV\s0 used is the value of \fBsalt\fR and *not* the \s-1IV\s0 returned by \fBEVP_BytesToKey()\fR. .SH "BUGS" .IX Header "BUGS" The \s-1PEM\s0 read routines in some versions of OpenSSL will not correctly reuse an existing structure. Therefore the following: .PP .Vb 1 \& PEM_read_bio_X509(bp, &x, 0, NULL); .Ve .PP where \fBx\fR already contains a valid certificate, may not work, whereas: .PP .Vb 2 \& X509_free(x); \& x = PEM_read_bio_X509(bp, NULL, 0, NULL); .Ve .PP is guaranteed to work. .SH "RETURN CODES" .IX Header "RETURN CODES" The read routines return either a pointer to the structure read or \s-1NULL\s0 if an error occurred. .PP The write routines return 1 for success or 0 for failure. .SH "SEE ALSO" .IX Header "SEE ALSO" \&\fBEVP_get_cipherbyname\fR\|(3), \fBEVP_BytesToKey\fR\|(3)
Save File
Cancel