NetBSD/lib/libcrypto/man/PKCS7_decrypt.3

.\"	$NetBSD: PKCS7_decrypt.3,v 1.5 2005/11/25 21:09:34 christos Exp $
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.\" ========================================================================
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.IX Title "PKCS7_decrypt 3"
.TH PKCS7_decrypt 3 "2003-07-24" "0.9.8a" "OpenSSL"
.SH "NAME"
PKCS7_decrypt \- decrypt content from a PKCS#7 envelopedData structure
.SH "LIBRARY"
libcrypto, -lcrypto
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
int PKCS7_decrypt(\s-1PKCS7\s0 *p7, \s-1EVP_PKEY\s0 *pkey, X509 *cert, \s-1BIO\s0 *data, int flags);
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fIPKCS7_decrypt()\fR extracts and decrypts the content from a PKCS#7 envelopedData
structure. \fBpkey\fR is the private key of the recipient, \fBcert\fR is the
recipients certificate, \fBdata\fR is a \s-1BIO\s0 to write the content to and
\&\fBflags\fR is an optional set of flags.
.SH "NOTES"
.IX Header "NOTES"
\&\fIOpenSSL_add_all_algorithms()\fR (or equivalent) should be called before using this
function or errors about unknown algorithms will occur.
.PP
Although the recipients certificate is not needed to decrypt the data it is needed
to locate the appropriate (of possible several) recipients in the PKCS#7 structure.
.PP
The following flags can be passed in the \fBflags\fR parameter.
.PP
If the \fB\s-1PKCS7_TEXT\s0\fR flag is set \s-1MIME\s0 headers for type \fBtext/plain\fR are deleted
from the content. If the content is not of type \fBtext/plain\fR then an error is
returned.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fIPKCS7_decrypt()\fR returns either 1 for success or 0 for failure.
The error can be obtained from \fIERR_get_error\fR\|(3)
.SH "BUGS"
.IX Header "BUGS"
\&\fIPKCS7_decrypt()\fR must be passed the correct recipient key and certificate. It would
be better if it could look up the correct key and certificate from a database.
.PP
The lack of single pass processing and need to hold all data in memory as
mentioned in \fIPKCS7_sign()\fR also applies to \fIPKCS7_verify()\fR.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fIERR_get_error\fR\|(3), \fIPKCS7_encrypt\fR\|(3)
.SH "HISTORY"
.IX Header "HISTORY"
\&\fIPKCS7_decrypt()\fR was added to OpenSSL 0.9.5