DragonFly On-Line Manual Pages
ERR(3) DragonFly Library Functions Manual ERR(3)
NAME
ERR -- OpenSSL error codes
SYNOPSIS
#include <openssl/err.h>
DESCRIPTION
When a call to the OpenSSL library fails, this is usually signaled by the
return value, and an error code is stored in an error queue associated
with the current thread. The ERR library provides functions to obtain
these error codes and textual error messages. The ERR_get_error(3) man-
page describes how to access error codes.
Error codes contain information about where the error occurred, and what
went wrong. ERR_GET_LIB(3) describes how to extract this information. A
method to obtain human-readable error messages is described in
ERR_error_string(3).
ERR_clear_error(3) can be used to clear the error queue.
Note that ERR_remove_state(3) should be used to avoid memory leaks when
threads are terminated.
ADDING NEW ERROR CODES TO OPENSSL
See ERR_put_error(3) if you want to record error codes in the OpenSSL
error system from within your application.
The remainder of this section is of interest only if you want to add new
error codes to OpenSSL or add error codes from external libraries.
When you are using new function or reason codes, run make errors. The
necessary #defines will then automatically be added to the sub-library's
header file.
Adding new libraries
When adding a new sub-library to OpenSSL, assign it a library number
ERR_LIB_XXX, define a macro XXXerr() (both in <openssl/err.h>), add its
name to ERR_str_libraries[] (in /usr/src/lib/libcrypto/err/err.c), and
add ERR_load_XXX_strings() to the ERR_load_crypto_strings() function (in
/usr/src/lib/libcrypto/err/err_all.c). Finally, add an entry
L XXX xxx.h xxx_err.c
to /usr/src/lib/libcrypto/err/openssl.ec, and add xxx_err.c to the
Makefile. Running make errors will then generate a file xxx_err.c, and
add all error codes used in the library to xxx.h.
Additionally the library include file must have a certain form. Typi-
cally it will initially look like this:
#ifndef HEADER_XXX_H
#define HEADER_XXX_H
#ifdef __cplusplus
extern "C" {
#endif
/* Include files */
#include <openssl/bio.h>
#include <openssl/x509.h>
/* Macros, structures and function prototypes */
/* BEGIN ERROR CODES */
The BEGIN ERROR CODES sequence is used by the error code generation
script as the point to place new error codes. Any text after this point
will be overwritten when make errors is run. The closing #endif etc.
will be automatically added by the script.
The generated C error code file xxx_err.c will load the header files
<stdio.h>, <openssl/err.h> and <openssl/xxx.h> so the header file must
load any additional header files containing any definitions it uses.
USING ERROR CODES IN EXTERNAL LIBRARIES
It is also possible to use OpenSSL's error code scheme in external
libraries. The library needs to load its own codes and call the OpenSSL
error code insertion script mkerr.pl explicitly to add codes to the
header file and generate the C error code file. This will normally be
done if the external library needs to generate new ASN.1 structures but
it can also be used to add more general purpose error code handling.
INTERNALS
The error queues are stored in a hash table with one ERR_STATE entry for
each PID. ERR_get_state() returns the current thread's ERR_STATE. An
ERR_STATE can hold up to ERR_NUM_ERRORS error codes. When more error
codes are added, the old ones are overwritten, on the assumption that the
most recent errors are most important.
Error strings are also stored in a hash table. The hash tables can be
obtained by calling ERR_get_err_state_table() and ERR_get_string_table().
SEE ALSO
CRYPTO_set_locking_callback(3), ERR_clear_error(3), ERR_error_string(3),
ERR_get_error(3), ERR_GET_LIB(3), ERR_load_crypto_strings(3),
ERR_load_strings(3), ERR_print_errors(3), ERR_put_error(3),
ERR_remove_state(3), ERR_set_mark(3), SSL_get_error(3)
DragonFly 5.5 November 23, 2016 DragonFly 5.5
ui(3) OpenSSL ui(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,
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);
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 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 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 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).
1.0.2h 2016-05-03 ui(3)