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Diffstat (limited to 'doc/crypto/ui.pod')
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diff --git a/doc/crypto/ui.pod b/doc/crypto/ui.pod new file mode 100644 index 0000000000..2b3535a746 --- /dev/null +++ b/doc/crypto/ui.pod @@ -0,0 +1,194 @@ +=pod + +=head1 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 + +=head1 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); + + 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); + +=head1 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 L<ui_create(3)|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 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 I<prompt> argument) and one describing +the possible answers (given through the I<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 is none provided by the method used) +creates a string "Enter I<description> for I<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<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. + +=head1 SEE ALSO + +L<ui_create(3)|ui_create(3)>, L<ui_compat(3)|ui_compat(3)> + +=head1 HISTORY + +The UI section was first introduced in OpenSSL 0.9.7. + +=head1 AUTHOR + +Richard Levitte (richard@levitte.org) for the OpenSSL project +(http://www.openssl.org). + +=cut |