@ -181,7 +181,7 @@ implementation includes the following abstractions;
=head2 Reference counting and handles
Due to the modular nature of the ENGINE API, pointers to ENGINEs need to be
treated as handles - ie. not only as pointers, but also as references to
treated as handles - i. e. not only as pointers, but also as references to
the underlying ENGINE object. Ie. one should obtain a new reference when
making copies of an ENGINE pointer if the copies will be used (and
released) independently.
@ -252,7 +252,7 @@ operational ENGINE for a given cryptographic purpose.
To obtain a functional reference from an existing structural reference,
call the ENGINE_init() function. This returns zero if the ENGINE was not
already operational and couldn't be successfully initialised (eg. lack of
already operational and couldn't be successfully initialised (e. g. lack of
system drivers, no special hardware attached, etc), otherwise it will
return nonzero to indicate that the ENGINE is now operational and will
have allocated a new B<functional> reference to the ENGINE. All functional
@ -260,7 +260,7 @@ references are released by calling ENGINE_finish() (which removes the
implicit structural reference as well).
The second way to get a functional reference is by asking OpenSSL for a
default implementation for a given task, eg. by ENGINE_get_default_RSA(),
default implementation for a given task, e. g. by ENGINE_get_default_RSA(),
ENGINE_get_default_cipher_engine(), etc. These are discussed in the next
section, though they are not usually required by application programmers as
they are used automatically when creating and using the relevant
@ -278,7 +278,7 @@ In the case of other abstractions like RSA, DSA, etc, there is only one
"algorithm" so all implementations implicitly register using the same 'nid'
index.
When a default ENGINE is requested for a given abstraction/algorithm/mode, (eg.
When a default ENGINE is requested for a given abstraction/algorithm/mode, (e. g.
when calling RSA_new_method(NULL)), a "get_default" call will be made to the
ENGINE subsystem to process the corresponding state table and return a
functional reference to an initialised ENGINE whose implementation should be
@ -328,7 +328,7 @@ is something for the application to control. Some applications
will want to allow the user to specify exactly which ENGINE they want used
if any is to be used at all. Others may prefer to load all support and have
OpenSSL automatically use at run-time any ENGINE that is able to
successfully initialise - ie. to assume that this corresponds to
successfully initialise - i. e. to assume that this corresponds to
acceleration hardware attached to the machine or some such thing. There are
probably numerous other ways in which applications may prefer to handle
things, so we will simply illustrate the consequences as they apply to a
@ -417,7 +417,7 @@ so that it can be initialised for use. This could include the path to any
driver or config files it needs to load, required network addresses,
smart-card identifiers, passwords to initialise protected devices,
logging information, etc etc. This class of commands typically needs to be
passed to an ENGINE B<before> attempting to initialise it, ie. before
passed to an ENGINE B<before> attempting to initialise it, i. e. before
calling ENGINE_init(). The other class of commands consist of settings or
operations that tweak certain behaviour or cause certain operations to take
place, and these commands may work either before or after ENGINE_init(), or
@ -490,7 +490,7 @@ It is possible to discover at run-time the names, numerical-ids, descriptions
and input parameters of the control commands supported by an ENGINE using a
structural reference. Note that some control commands are defined by OpenSSL
itself and it will intercept and handle these control commands on behalf of the
ENGINE, ie. the ENGINE's ctrl() handler is not used for the control command.
ENGINE, i. e. the ENGINE's ctrl() handler is not used for the control command.
openssl/engine.h defines an index, ENGINE_CMD_BASE, that all control commands
implemented by ENGINEs should be numbered from. Any command value lower than
this symbol is considered a "generic" command is handled directly by the
@ -556,7 +556,7 @@ by applications, administrations, users, etc. These can support arbitrary
operations via ENGINE_ctrl(), including passing to and/or from the control
commands data of any arbitrary type. These commands are supported in the
discovery mechanisms simply to allow applications to determine if an ENGINE
supports certain specific commands it might want to use (eg. application "foo"
supports certain specific commands it might want to use (e. g. application "foo"
might query various ENGINEs to see if they implement "FOO_GET_VENDOR_LOGO_GIF" -
and ENGINE could therefore decide whether or not to support this "foo"-specific
extension).
Gustaf Neumann
3 years ago
committed by