/xlv3/openssl/0.9.7e-sgipl1/work/0.9.7e-sgipl1/openssl-
0.9.7e/doc/crypto
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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, ERR_load_UI_strings - New User
Interface
SYNOPSIS
#include <openssl/ui.h>
typedef struct ui_st UI;
typedef struct ui_method_st UI_METHOD;
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);
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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 general purpose set of
routines to prompt the user for text-based information.
Through user-written methods (see ui_create(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 with UI_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 the
default one, since the default can be changed. See further
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on). This method is the most machine/OS dependent part of
OpenSSL and normally generates the most problems when
porting.
UI_free() removes a UI from memory, along with all other
pieces of memory that's connected to it, like duplicated
input strings, results and others.
UI_add_input_string() and UI_add_verify_string() add a
prompt to the UI, as well as flags and a result buffer and
the desired minimum and maximum sizes of the result. 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 and 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 the 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: an
description and a name. The default constructor (if there
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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 piece of memory 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, it replaces the previous blob 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.
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.
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.
SEE ALSO
ui_create(3), ui_compat(3)
HISTORY
The UI section was first introduced in OpenSSL 0.9.7.
AUTHOR
Richard Levitte (richard@levitte.org) for the OpenSSL
project (http://www.openssl.org).
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