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Improve formatting for man3/EC_GROUP_new.pod

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- Use `()` to qualify function names, consistently
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Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9874)
This commit is contained in:
Nicola Tuveri 2019-10-18 16:24:08 +03:00
parent 4a7a497229
commit 4fc55c1da9
1 changed files with 63 additions and 43 deletions
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doc/man3/EC_GROUP_new.pod
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@ -66,55 +66,68 @@ L<openssl_user_macros(7)>:
=head1 DESCRIPTION
Within the library there are two forms of elliptic curve that are of interest. The first form is those defined over the
prime field Fp. The elements of Fp are the integers 0 to p-1, where p is a prime number. This gives us a revised
Within the library there are two forms of elliptic curve that are of interest.
The first form is those defined over the prime field Fp. The elements of Fp are
the integers 0 to p-1, where p is a prime number. This gives us a revised
elliptic curve equation as follows:
y^2 mod p = x^3 +ax + b mod p
The second form is those defined over a binary field F2^m where the elements of the field are integers of length at
most m bits. For this form the elliptic curve equation is modified to:
The second form is those defined over a binary field F2^m where the elements of
the field are integers of length at most m bits. For this form the elliptic
curve equation is modified to:
y^2 + xy = x^3 + ax^2 + b (where b != 0)
Operations in a binary field are performed relative to an B<irreducible polynomial>. All such curves with OpenSSL
use a trinomial or a pentanomial for this parameter.
Operations in a binary field are performed relative to an
B<irreducible polynomial>. All such curves with OpenSSL use a trinomial or a
pentanomial for this parameter.
A new curve can be constructed by calling EC_GROUP_new_ex, using the implementation provided by B<meth> (see
L<EC_GFp_simple_method(3)>) and associated with the library context B<ctx>
(see L<OPENSSL_CTX(3)>).
The B<ctx> parameter may be NULL in which case the default library context is used.
A new curve can be constructed by calling EC_GROUP_new_ex(), using the
implementation provided by B<meth> (see L<EC_GFp_simple_method(3)>) and
associated with the library context B<ctx> (see L<OPENSSL_CTX(3)>).
The B<ctx> parameter may be NULL in which case the default library context is
used.
It is then necessary to call EC_GROUP_set_curve() to set the curve parameters.
EC_GROUP_new_from_ecparameters() will create a group from the
specified B<params> and
EC_GROUP_new_from_ecpkparameters() will create a group from the specific PK B<params>.
EC_GROUP_new_from_ecpkparameters() will create a group from the specific PK
B<params>.
EC_GROUP_new is the same as EC_GROUP_new_ex() except that the library context
EC_GROUP_new() is the same as EC_GROUP_new_ex() except that the library context
used is always the default library context.
EC_GROUP_set_curve() sets the curve parameters B<p>, B<a> and B<b>. For a curve over Fp B<b>
is the prime for the field. For a curve over F2^m B<p> represents the irreducible polynomial - each bit
represents a term in the polynomial. Therefore there will either be three or five bits set dependent on whether
the polynomial is a trinomial or a pentanomial.
EC_GROUP_set_curve() sets the curve parameters B<p>, B<a> and B<b>. For a curve
over Fp B<b> is the prime for the field. For a curve over F2^m B<p> represents
the irreducible polynomial - each bit represents a term in the polynomial.
Therefore there will either be three or five bits set dependent on whether the
polynomial is a trinomial or a pentanomial.
EC_group_get_curve() obtains the previously set curve parameters.
EC_GROUP_set_curve_GFp() and EC_GROUP_set_curve_GF2m() are synonyms for EC_GROUP_set_curve(). They are defined for
backwards compatibility only and should not be used.
EC_GROUP_set_curve_GFp() and EC_GROUP_set_curve_GF2m() are synonyms for
EC_GROUP_set_curve(). They are defined for backwards compatibility only and
should not be used.
EC_GROUP_get_curve_GFp() and EC_GROUP_get_curve_GF2m() are synonyms for EC_GROUP_get_curve(). They are defined for
backwards compatibility only and should not be used.
EC_GROUP_get_curve_GFp() and EC_GROUP_get_curve_GF2m() are synonyms for
EC_GROUP_get_curve(). They are defined for backwards compatibility only and
should not be used.
The functions EC_GROUP_new_curve_GFp and EC_GROUP_new_curve_GF2m are shortcuts for calling EC_GROUP_new and then the
EC_GROUP_set_curve function. An appropriate default implementation method will be used.
The functions EC_GROUP_new_curve_GFp() and EC_GROUP_new_curve_GF2m() are
shortcuts for calling EC_GROUP_new() and then the EC_GROUP_set_curve() function.
An appropriate default implementation method will be used.
Whilst the library can be used to create any curve using the functions described above, there are also a number of
predefined curves that are available. In order to obtain a list of all of the predefined curves, call the function
EC_get_builtin_curves(). The parameter B<r> should be an array of EC_builtin_curve structures of size B<nitems>. The function
will populate the B<r> array with information about the built-in curves. If B<nitems> is less than the total number of
curves available, then the first B<nitems> curves will be returned. Otherwise the total number of curves will be
provided. The return value is the total number of curves available (whether that number has been populated in B<r> or
not). Passing a NULL B<r>, or setting B<nitems> to 0 will do nothing other than return the total number of curves available.
Whilst the library can be used to create any curve using the functions described
above, there are also a number of predefined curves that are available. In order
to obtain a list of all of the predefined curves, call the function
EC_get_builtin_curves(). The parameter B<r> should be an array of
EC_builtin_curve structures of size B<nitems>. The function will populate the
B<r> array with information about the built-in curves. If B<nitems> is less than
the total number of curves available, then the first B<nitems> curves will be
returned. Otherwise the total number of curves will be provided. The return
value is the total number of curves available (whether that number has been
populated in B<r> or not). Passing a NULL B<r>, or setting B<nitems> to 0 will
do nothing other than return the total number of curves available.
The EC_builtin_curve structure is defined as follows:
typedef struct {
@ -122,31 +135,37 @@ The EC_builtin_curve structure is defined as follows:
const char *comment;
} EC_builtin_curve;
Each EC_builtin_curve item has a unique integer id (B<nid>), and a human readable comment string describing the curve.
Each EC_builtin_curve item has a unique integer id (B<nid>), and a human
readable comment string describing the curve.
In order to construct a built-in curve use the function EC_GROUP_new_by_curve_name_ex and provide the B<nid> of the curve to
be constructed and the associated library context to be used in B<ctx> (see L<OPENSSL_CTX(3)>).
The B<ctx> value may be NULL in which case the default library context is used.
In order to construct a built-in curve use the function
EC_GROUP_new_by_curve_name_ex() and provide the B<nid> of the curve to be
constructed and the associated library context to be used in B<ctx> (see
L<OPENSSL_CTX(3)>). The B<ctx> value may be NULL in which case the default
library context is used.
EC_GROUP_new_by_curve_name is the same as EC_GROUP_new_by_curve_name_ex except
that the default library context is always used.
EC_GROUP_new_by_curve_name() is the same as EC_GROUP_new_by_curve_name_ex()
except that the default library context is always used.
EC_GROUP_free frees the memory associated with the EC_GROUP.
EC_GROUP_free() frees the memory associated with the EC_GROUP.
If B<group> is NULL nothing is done.
EC_GROUP_clear_free is deprecated: it was meant to destroy any sensitive data
EC_GROUP_clear_free() is deprecated: it was meant to destroy any sensitive data
held within the EC_GROUP and then free its memory, but since all the data stored
in the EC_GROUP is public anyway, this function is unnecessary.
Its use can be safely replaced with EC_GROUP_free.
Its use can be safely replaced with EC_GROUP_free().
If B<group> is NULL nothing is done.
=head1 RETURN VALUES
All EC_GROUP_new* functions return a pointer to the newly constructed group, or NULL on error.
All EC_GROUP_new* functions return a pointer to the newly constructed group, or
NULL on error.
EC_get_builtin_curves returns the number of built-in curves that are available.
EC_get_builtin_curves() returns the number of built-in curves that are
available.
EC_GROUP_set_curve_GFp, EC_GROUP_get_curve_GFp, EC_GROUP_set_curve_GF2m, EC_GROUP_get_curve_GF2m return 1 on success or 0 on error.
EC_GROUP_set_curve_GFp(), EC_GROUP_get_curve_GFp(), EC_GROUP_set_curve_GF2m(),
EC_GROUP_get_curve_GF2m() return 1 on success or 0 on error.
=head1 SEE ALSO
@ -161,11 +180,12 @@ L<OPENSSL_CTX(3)>
=item *
EC_GROUP_new_ex and EC_GROUP_new_by_curve_name_ex were added in OpenSSL 3.0.
EC_GROUP_new_ex() and EC_GROUP_new_by_curve_name_ex() were added in OpenSSL 3.0.
=item *
EC_GROUP_clear_free() was deprecated in OpenSSL 3.0; use EC_GROUP_free() instead.
EC_GROUP_clear_free() was deprecated in OpenSSL 3.0; use EC_GROUP_free()
instead.
=back