=head1 SYNOPSIS
- X509 *d2i_X509(X509 **px, unsigned char **in, int len);
+ #include <openssl/x509.h>
+
+ X509 *d2i_X509(X509 **px, const unsigned char **in, int len);
int i2d_X509(X509 *x, unsigned char **out);
X509 *d2i_X509_bio(BIO *bp, X509 **x);
X509 *d2i_X509_fp(FILE *fp, X509 **x);
- int i2d_X509_bio(X509 *x, BIO *bp);
- int i2d_X509_fp(X509 *x, FILE *fp);
+ int i2d_X509_bio(BIO *bp, X509 *x);
+ int i2d_X509_fp(FILE *fp, X509 *x);
+
+ int i2d_re_X509_tbs(X509 *x, unsigned char **out);
=head1 DESCRIPTION
The X509 encode and decode routines encode and parse an
B<X509> structure, which represents an X509 certificate.
-d2i_X509() attempts to decode B<len> bytes at B<*out>. If
+d2i_X509() attempts to decode B<len> bytes at B<*in>. If
successful a pointer to the B<X509> structure is returned. If an error
occurred then B<NULL> is returned. If B<px> is not B<NULL> then the
returned structure is written to B<*px>. If B<*px> is not B<NULL>
then it is assumed that B<*px> contains a valid B<X509>
-structure and an attempt is made to reuse it. If the call is
-successful B<*out> is incremented to the byte following the
+structure and an attempt is made to reuse it. This "reuse" capability is present
+for historical compatibility but its use is B<strongly discouraged> (see BUGS
+below, and the discussion in the RETURN VALUES section).
+
+If the call is successful B<*in> is incremented to the byte following the
parsed data.
i2d_X509() encodes the structure pointed to by B<x> into DER format.
to parse data from FILE pointer B<fp>.
i2d_X509_bio() is similar to i2d_X509() except it writes
-the encoding of the structure B<x> to BIO B<bp>.
+the encoding of the structure B<x> to BIO B<bp> and it
+returns 1 for success and 0 for failure.
i2d_X509_fp() is similar to i2d_X509() except it writes
-the encoding of the structure B<x> to BIO B<bp>.
+the encoding of the structure B<x> to BIO B<bp> and it
+returns 1 for success and 0 for failure.
+
+i2d_re_X509_tbs() is similar to i2d_X509() except it encodes
+only the TBSCertificate portion of the certificate.
=head1 NOTES
The letters B<i> and B<d> in for example B<i2d_X509> stand for
-"internal" (that is an internal C structure) and "DER". So that
-B<i2d_X509> converts from internal to DER.
+"internal" (that is an internal C structure) and "DER". So
+B<i2d_X509> converts from internal to DER. The "re" in
+B<i2d_re_X509_tbs> stands for "re-encode", and ensures that a fresh
+encoding is generated in case the object has been modified after
+creation (see the BUGS section).
The functions can also understand B<BER> forms.
fixed in future so code should not assume that i2d_X509() will
always succeed.
+The encoding of the TBSCertificate portion of a certificate is cached
+in the B<X509> structure internally to improve encoding performance
+and to ensure certificate signatures are verified correctly in some
+certificates with broken (non-DER) encodings.
+
+Any function which encodes an X509 structure such as i2d_X509(),
+i2d_X509_fp() or i2d_X509_bio() may return a stale encoding if the
+B<X509> structure has been modified after deserialization or previous
+serialization.
+
+If, after modification, the B<X509> object is re-signed with X509_sign(),
+the encoding is automatically renewed. Otherwise, the encoding of the
+TBSCertificate portion of the B<X509> can be manually renewed by calling
+i2d_re_X509_tbs().
+
=head1 RETURN VALUES
d2i_X509(), d2i_X509_bio() and d2i_X509_fp() return a valid B<X509> structure
or B<NULL> if an error occurs. The error code that can be obtained by
+L<ERR_get_error(3)|ERR_get_error(3)>. If the "reuse" capability has been used
+with a valid X509 structure being passed in via B<px> then the object is not
+freed in the event of error but may be in a potentially invalid or inconsistent
+state.
+
+i2d_X509() returns the number of bytes successfully encoded or a negative
+value if an error occurs. The error code can be obtained by
L<ERR_get_error(3)|ERR_get_error(3)>.
-i2d_X509(), i2d_X509_bio() and i2d_X509_fp() return a the number of bytes
-successfully encoded or a negative value if an error occurs. The error code
-can be obtained by L<ERR_get_error(3)|ERR_get_error(3)>.
+i2d_X509_bio() and i2d_X509_fp() return 1 for success and 0 if an error
+occurs The error code can be obtained by L<ERR_get_error(3)|ERR_get_error(3)>.
=head1 SEE ALSO
projects / openssl.git / blobdiff