Sortix nightly manual
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UI_NEW(3) | Library Functions Manual | UI_NEW(3) |
NAME
UI_new
,
UI_new_method
,
UI_free
,
UI_add_input_string
,
UI_dup_input_string
,
UI_add_verify_string
,
UI_dup_verify_string
,
UI_add_input_boolean
,
UI_dup_input_boolean
,
UI_add_info_string
,
UI_dup_info_string
,
UI_add_error_string
,
UI_dup_error_string
,
UI_construct_prompt
,
UI_add_user_data
,
UI_get0_user_data
,
UI_get0_result
,
UI_process
,
UI_ctrl
,
UI_set_default_method
,
UI_get_default_method
,
UI_get_method
,
UI_set_method
,
UI_OpenSSL
—
New User Interface
SYNOPSIS
#include
<openssl/ui.h>
UI *
UI_new
(void);
UI *
UI_new_method
(const
UI_METHOD *method);
void
UI_free
(UI
*ui);
int
UI_add_input_string
(UI
*ui, const char *prompt,
int flags, char
*result_buf, int minsize,
int maxsize);
int
UI_dup_input_string
(UI
*ui, const char *prompt,
int flags, char
*result_buf, int minsize,
int maxsize);
int
UI_add_verify_string
(UI
*ui, const char *prompt,
int flags, char
*result_buf, int minsize,
int maxsize, const
char *test_buf);
int
UI_dup_verify_string
(UI
*ui, const char *prompt,
int flags, char
*result_buf, int minsize,
int maxsize, const
char *test_buf);
int
UI_add_input_boolean
(UI
*ui, const char *prompt,
const char *action_desc,
const char *ok_chars,
const char *cancel_chars,
int flags, char
*result_buf);
int
UI_dup_input_boolean
(UI
*ui, const char *prompt,
const char *action_desc,
const char *ok_chars,
const char *cancel_chars,
int flags, char
*result_buf);
int
UI_add_info_string
(UI
*ui, const char *text);
int
UI_dup_info_string
(UI
*ui, const char *text);
int
UI_add_error_string
(UI
*ui, const char *text);
int
UI_dup_error_string
(UI
*ui, const char *text);
/* These are the possible flags. They can be OR'ed
together. */
#define UI_INPUT_FLAG_ECHO 0x01
#define UI_INPUT_FLAG_DEFAULT_PWD 0x02
char *
UI_construct_prompt
(UI
*ui_method, const char *object_desc,
const char *object_name);
void *
UI_add_user_data
(UI
*ui, void *user_data);
void *
UI_get0_user_data
(UI
*ui);
const char *
UI_get0_result
(UI
*ui, int i);
int
UI_process
(UI
*ui);
int
UI_ctrl
(UI
*ui, int cmd,
long i, void
*p, void (*f)());
#define UI_CTRL_PRINT_ERRORS 1
#define UI_CTRL_IS_REDOABLE 2
void
UI_set_default_method
(const
UI_METHOD *meth);
const UI_METHOD *
UI_get_default_method
(void);
const UI_METHOD *
UI_get_method
(UI
*ui);
const UI_METHOD *
UI_set_method
(UI
*ui, const UI_METHOD *meth);
UI_METHOD *
UI_OpenSSL
(void);
DESCRIPTION
UI stands for User Interface, and is a general purpose set of routines to prompt the user for text-based information. Through user-written methods (see UI_create_method(3)), prompting can be done in any way imaginable, be it plain text prompting, through dialog boxes or from a cell phone. All the functions work through a context of the type UI. This context contains all the information needed to prompt correctly as well as a reference to a UI_METHOD, which is an ordered vector of functions that carry out the actual prompting. The first thing to do is to create a UI withUI_new
() or
UI_new_method
(), then add information to it
with the UI_add_*
() or
UI_dup_*
() functions. Also, user-defined
random data can be passed down to the underlying method through calls to
UI_add_user_data
(). The default UI method
doesn't care about these data, but other methods might. Finally, use
UI_process
() to actually perform the
prompting and UI_get0_result
() to find the
result to the prompt.
A UI can contain more than one prompt, which
are performed in the given sequence. Each prompt gets an index number which is
returned by the UI_add_*
() and
UI_dup_*
() functions, and has to be used to
get the corresponding result with
UI_get0_result
().
The functions are as follows:
UI_new
() creates a new
UI using the default UI method. When done
with this UI, it should be freed using
UI_free
().
UI_new_method
() creates a new
UI using the given UI method. When done with
this UI, it should be freed using
UI_free
().
UI_OpenSSL
() returns the built-in UI method
(note: not necessarily the default one, since the default can be changed. See
further on). This method is the most machine/OS dependent part of OpenSSL and
normally generates the most problems when porting.
UI_free
() removes
ui from memory, along with all other pieces
of memory that are connected to it, like duplicated input strings, results and
others. If ui is a
NULL
pointer, no action occurs.
UI_add_input_string
() and
UI_add_verify_string
() add a prompt to
ui, as well as flags and a result buffer and
the desired minimum and maximum sizes of the result, not counting the final
NUL character. The given information is used to prompt for information, for
example a password, and to verify a password (i.e. having the user enter it
twice and check that the same string was entered twice).
UI_add_verify_string
() takes an extra
argument that should be a pointer to the result buffer of the input string
that it's supposed to verify, or verification will fail.
UI_add_input_boolean
() adds a prompt to
ui that's supposed to be answered in a
boolean way, with a single character for yes and a different character for no.
A set of characters that can be used to cancel the prompt is given as well.
The prompt itself is really divided in two, one part being the descriptive
text (given through the prompt argument) and
one describing the possible answers (given through the
action_desc argument).
UI_add_info_string
() and
UI_add_error_string
() add strings that are
shown at the same time as the prompt for extra information or to show an error
string. The difference between the two is only conceptual. With the builtin
method, there's no technical difference between them. Other methods may make a
difference between them, however.
The flags currently supported are
UI_INPUT_FLAG_ECHO
, which is relevant for
UI_add_input_string
() and will have the
users response be echoed (when prompting for a password, this flag should
obviously not be used), and
UI_INPUT_FLAG_DEFAULT_PWD
, which means that
a default password of some sort will be used (completely depending on the
application and the UI method).
UI_dup_input_string
(),
UI_dup_verify_string
(),
UI_dup_input_boolean
(),
UI_dup_info_string
(), and
UI_dup_error_string
() are basically the
same as their UI_add_*
() counterparts,
except that they make their own copies of all strings.
UI_construct_prompt
() is a helper function
that can be used to create a prompt from two pieces of information: a
description and a name. The default constructor (if there is none provided by
the method used) creates a string "Enter
description for
name:". With the description "pass
phrase" and the file name "foo.key", that becomes "Enter
pass phrase for foo.key:". Other methods may create whatever string and
may include encodings that will be processed by the other method functions.
UI_add_user_data
() adds a user data pointer
for the method to use at any time. The builtin UI method doesn't care about
this info. Note that several calls to this function doesn't add data - the
previous blob is replaced with the one given as argument.
UI_get0_user_data
() retrieves the data that
has last been given to the ui with
UI_add_user_data
().
UI_get0_result
() returns a pointer to the
result buffer associated with the information indexed by
i.
UI_process
() goes through the information
given so far, does all the printing and prompting and returns the final
status, which is -2 on out-of-band events (Interrupt, Cancel, ...), -1 on
error, or 0 on success.
UI_ctrl
() adds extra control for the
application author. For now, it understands two commands:
UI_CTRL_PRINT_ERRORS
, which makes
UI_process
() print the OpenSSL error stack
as part of processing the ui, and
UI_CTRL_IS_REDOABLE
, which returns a flag
saying if the used ui can be used again or
not.
UI_set_default_method
() changes the default
UI method to the one given. This function is not thread-safe and should not be
called at the same time as other OpenSSL functions.
UI_get_default_method
() returns a pointer to
the current default UI method.
UI_get_method
() returns the UI method
associated with a given ui.
UI_set_method
() changes the UI method
associated with a given ui.
RETURN VALUES
UI_new
() and
UI_new_method
() return a valid
UI structure or
NULL
if an error occurred.
UI_add_input_string
(),
UI_dup_input_string
(),
UI_add_verify_string
(),
UI_dup_verify_string
(),
UI_add_input_boolean
(),
UI_dup_input_boolean
(),
UI_add_info_string
(),
UI_dup_info_string
(),
UI_add_error_string
(), and
UI_dup_error_string
() return a positive
number on success or a number less than or equal to zero otherwise.
UI_construct_prompt
() and
UI_get0_result
() return a string or
NULL
if an error occurred.
UI_add_user_data
() and
UI_get0_user_data
() return a pointer to the
user data that was contained in ui before the
call. In particular, NULL
is a valid return
value.
UI_process
() returns 0 on success or a
negative value on error.
UI_ctrl
() returns a mask on success or -1 on
error.
UI_get_default_method
() and
UI_OpenSSL
() always return a pointer to a
valid UI_METHOD structure.
UI_get_method
() and
UI_set_method
() return a pointer to the
UI_METHOD structure that is installed in
ui after the call. The OpenSSL documentation
says that they can fail and return NULL
,
but currently, this can only happen when and after
UI_set_method
() is called with an explicit
NULL
argument.
SEE ALSO
crypto(3), UI_create_method(3), UI_get_string_type(3), UI_UTIL_read_pw(3)HISTORY
These functions first appeared in OpenSSL 0.9.7 and have been available since OpenBSD 3.2.AUTHORS
Richard Levitte <richard@levitte.org> for the OpenSSL project.June 19, 2020 | Debian |