1/*
2 * ModExp / RSA (with/without KM) plugin API
3 *
4 * The application will load a dynamic library which
5 * exports entrypoint(s) defined in this file.
6 *
7 * This set of entrypoints provides only a multithreaded,
8 * synchronous-within-each-thread, facility.
9 *
10 *
11 * This file is Copyright 1998-2000 nCipher Corporation Limited.
12 *
13 * Redistribution and use in source and binary forms, with opr without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 *
17 * 1. Redistributions of source code must retain the copyright notice,
18 *    this list of conditions, and the following disclaimer.
19 *
20 * 2. Redistributions in binary form must reproduce the above
21 *    copyright notice, this list of conditions, and the following
22 *    disclaimer, in the documentation and/or other materials provided
23 *    with the distribution
24 *
25 * IN NO EVENT SHALL NCIPHER CORPORATION LIMITED (`NCIPHER') AND/OR
26 * ANY OTHER AUTHORS OR DISTRIBUTORS OF THIS FILE BE LIABLE for any
27 * damages arising directly or indirectly from this file, its use or
28 * this licence.  Without prejudice to the generality of the
29 * foregoing: all liability shall be excluded for direct, indirect,
30 * special, incidental, consequential or other damages or any loss of
31 * profits, business, revenue goodwill or anticipated savings;
32 * liability shall be excluded even if nCipher or anyone else has been
33 * advised of the possibility of damage.  In any event, if the
34 * exclusion of liability is not effective, the liability of nCipher
35 * or any author or distributor shall be limited to the lesser of the
36 * price paid and 1,000 pounds sterling. This licence only fails to
37 * exclude or limit liability for death or personal injury arising out
38 * of negligence, and only to the extent that such an exclusion or
39 * limitation is not effective.
40 *
41 * NCIPHER AND THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ALL
42 * AND ANY WARRANTIES (WHETHER EXPRESS OR IMPLIED), including, but not
43 * limited to, any implied warranties of merchantability, fitness for
44 * a particular purpose, satisfactory quality, and/or non-infringement
45 * of any third party rights.
46 *
47 * US Government use: This software and documentation is Commercial
48 * Computer Software and Computer Software Documentation, as defined in
49 * sub-paragraphs (a)(1) and (a)(5) of DFAR 252.227-7014, "Rights in
50 * Noncommercial Computer Software and Noncommercial Computer Software
51 * Documentation."  Use, duplication or disclosure by the Government is
52 * subject to the terms and conditions specified here.
53 *
54 * By using or distributing this file you will be accepting these
55 * terms and conditions, including the limitation of liability and
56 * lack of warranty.  If you do not wish to accept these terms and
57 * conditions, DO NOT USE THE FILE.
58 *
59 *
60 * The actual dynamically loadable plugin, and the library files for
61 * static linking, which are also provided in some distributions, are
62 * not covered by the licence described above.  You should have
63 * received a separate licence with terms and conditions for these
64 * library files; if you received the library files without a licence,
65 * please contact nCipher.
66 *
67 *
68 * $Id: hwcryptohook.h,v 1.1 2002/10/11 17:10:59 levitte Exp $
69 */
70
71#ifndef HWCRYPTOHOOK_H
72#define HWCRYPTOHOOK_H
73
74#include <sys/types.h>
75#include <stdio.h>
76
77#ifndef HWCRYPTOHOOK_DECLARE_APPTYPES
78#define HWCRYPTOHOOK_DECLARE_APPTYPES 1
79#endif
80
81#define HWCRYPTOHOOK_ERROR_FAILED   -1
82#define HWCRYPTOHOOK_ERROR_FALLBACK -2
83#define HWCRYPTOHOOK_ERROR_MPISIZE  -3
84
85#if HWCRYPTOHOOK_DECLARE_APPTYPES
86
87/* These structs are defined by the application and opaque to the
88 * crypto plugin.  The application may define these as it sees fit.
89 * Default declarations are provided here, but the application may
90 *  #define HWCRYPTOHOOK_DECLARE_APPTYPES 0
91 * to prevent these declarations, and instead provide its own
92 * declarations of these types.  (Pointers to them must still be
93 * ordinary pointers to structs or unions, or the resulting combined
94 * program will have a type inconsistency.)
95 */
96typedef struct HWCryptoHook_MutexValue HWCryptoHook_Mutex;
97typedef struct HWCryptoHook_CondVarValue HWCryptoHook_CondVar;
98typedef struct HWCryptoHook_PassphraseContextValue HWCryptoHook_PassphraseContext;
99typedef struct HWCryptoHook_CallerContextValue HWCryptoHook_CallerContext;
100
101#endif /* HWCRYPTOHOOK_DECLARE_APPTYPES */
102
103/* These next two structs are opaque to the application.  The crypto
104 * plugin will return pointers to them; the caller simply manipulates
105 * the pointers.
106 */
107typedef struct HWCryptoHook_Context *HWCryptoHook_ContextHandle;
108typedef struct HWCryptoHook_RSAKey *HWCryptoHook_RSAKeyHandle;
109
110typedef struct {
111  char *buf;
112  size_t size;
113} HWCryptoHook_ErrMsgBuf;
114/* Used for error reporting.  When a HWCryptoHook function fails it
115 * will return a sentinel value (0 for pointer-valued functions, or a
116 * negative number, usually HWCRYPTOHOOK_ERROR_FAILED, for
117 * integer-valued ones).  It will, if an ErrMsgBuf is passed, also put
118 * an error message there.
119 *
120 * size is the size of the buffer, and will not be modified.  If you
121 * pass 0 for size you must pass 0 for buf, and nothing will be
122 * recorded (just as if you passed 0 for the struct pointer).
123 * Messages written to the buffer will always be null-terminated, even
124 * when truncated to fit within size bytes.
125 *
126 * The contents of the buffer are not defined if there is no error.
127 */
128
129typedef struct HWCryptoHook_MPIStruct {
130  unsigned char *buf;
131  size_t size;
132} HWCryptoHook_MPI;
133/* When one of these is returned, a pointer is passed to the function.
134 * At call, size is the space available.  Afterwards it is updated to
135 * be set to the actual length (which may be more than the space available,
136 * if there was not enough room and the result was truncated).
137 * buf (the pointer) is not updated.
138 *
139 * size is in bytes and may be zero at call or return, but must be a
140 * multiple of the limb size.  Zero limbs at the MS end are not
141 * permitted.
142 */
143
144#define HWCryptoHook_InitFlags_FallbackModExp    0x0002UL
145#define HWCryptoHook_InitFlags_FallbackRSAImmed  0x0004UL
146/* Enable requesting fallback to software in case of problems with the
147 * hardware support.  This indicates to the crypto provider that the
148 * application is prepared to fall back to software operation if the
149 * ModExp* or RSAImmed* functions return HWCRYPTOHOOK_ERROR_FALLBACK.
150 * Without this flag those calls will never return
151 * HWCRYPTOHOOK_ERROR_FALLBACK.  The flag will also cause the crypto
152 * provider to avoid repeatedly attempting to contact dead hardware
153 * within a short interval, if appropriate.
154 */
155
156#define HWCryptoHook_InitFlags_SimpleForkCheck   0x0010UL
157/* Without _SimpleForkCheck the library is allowed to assume that the
158 * application will not fork and call the library in the child(ren).
159 *
160 * When it is specified, this is allowed.  However, after a fork
161 * neither parent nor child may unload any loaded keys or call
162 * _Finish.  Instead, they should call exit (or die with a signal)
163 * without calling _Finish.  After all the children have died the
164 * parent may unload keys or call _Finish.
165 *
166 * This flag only has any effect on UN*X platforms.
167 */
168
169typedef struct {
170  unsigned long flags;
171  void *logstream; /* usually a FILE*.  See below. */
172
173  size_t limbsize; /* bignum format - size of radix type, must be power of 2 */
174  int mslimbfirst; /* 0 or 1 */
175  int msbytefirst; /* 0 or 1; -1 = native */
176
177  /* All the callback functions should return 0 on success, or a
178   * nonzero integer (whose value will be visible in the error message
179   * put in the buffer passed to the call).
180   *
181   * If a callback is not available pass a null function pointer.
182   *
183   * The callbacks may not call down again into the crypto plugin.
184   */
185
186  /* For thread-safety.  Set everything to 0 if you promise only to be
187   * singlethreaded.  maxsimultaneous is the number of calls to
188   * ModExp[Crt]/RSAImmed{Priv,Pub}/RSA.  If you don't know what to
189   * put there then say 0 and the hook library will use a default.
190   *
191   * maxmutexes is a small limit on the number of simultaneous mutexes
192   * which will be requested by the library.  If there is no small
193   * limit, set it to 0.  If the crypto plugin cannot create the
194   * advertised number of mutexes the calls to its functions may fail.
195   * If a low number of mutexes is advertised the plugin will try to
196   * do the best it can.  Making larger numbers of mutexes available
197   * may improve performance and parallelism by reducing contention
198   * over critical sections.  Unavailability of any mutexes, implying
199   * single-threaded operation, should be indicated by the setting
200   * mutex_init et al to 0.
201   */
202  int maxmutexes;
203  int maxsimultaneous;
204  size_t mutexsize;
205  int (*mutex_init)(HWCryptoHook_Mutex*, HWCryptoHook_CallerContext *cactx);
206  int (*mutex_acquire)(HWCryptoHook_Mutex*);
207  void (*mutex_release)(HWCryptoHook_Mutex*);
208  void (*mutex_destroy)(HWCryptoHook_Mutex*);
209
210  /* For greater efficiency, can use condition vars internally for
211   * synchronisation.  In this case maxsimultaneous is ignored, but
212   * the other mutex stuff must be available.  In singlethreaded
213   * programs, set everything to 0.
214   */
215  size_t condvarsize;
216  int (*condvar_init)(HWCryptoHook_CondVar*, HWCryptoHook_CallerContext *cactx);
217  int (*condvar_wait)(HWCryptoHook_CondVar*, HWCryptoHook_Mutex*);
218  void (*condvar_signal)(HWCryptoHook_CondVar*);
219  void (*condvar_broadcast)(HWCryptoHook_CondVar*);
220  void (*condvar_destroy)(HWCryptoHook_CondVar*);
221
222  /* The semantics of acquiring and releasing mutexes and broadcasting
223   * and waiting on condition variables are expected to be those from
224   * POSIX threads (pthreads).  The mutexes may be (in pthread-speak)
225   * fast mutexes, recursive mutexes, or nonrecursive ones.
226   *
227   * The _release/_signal/_broadcast and _destroy functions must
228   * always succeed when given a valid argument; if they are given an
229   * invalid argument then the program (crypto plugin + application)
230   * has an internal error, and they should abort the program.
231   */
232
233  int (*getpassphrase)(const char *prompt_info,
234                       int *len_io, char *buf,
235                       HWCryptoHook_PassphraseContext *ppctx,
236                       HWCryptoHook_CallerContext *cactx);
237  /* Passphrases and the prompt_info, if they contain high-bit-set
238   * characters, are UTF-8.  The prompt_info may be a null pointer if
239   * no prompt information is available (it should not be an empty
240   * string).  It will not contain text like `enter passphrase';
241   * instead it might say something like `Operator Card for John
242   * Smith' or `SmartCard in nFast Module #1, Slot #1'.
243   *
244   * buf points to a buffer in which to return the passphrase; on
245   * entry *len_io is the length of the buffer.  It should be updated
246   * by the callback.  The returned passphrase should not be
247   * null-terminated by the callback.
248   */
249
250  int (*getphystoken)(const char *prompt_info,
251                      const char *wrong_info,
252                      HWCryptoHook_PassphraseContext *ppctx,
253                      HWCryptoHook_CallerContext *cactx);
254  /* Requests that the human user physically insert a different
255   * smartcard, DataKey, etc.  The plugin should check whether the
256   * currently inserted token(s) are appropriate, and if they are it
257   * should not make this call.
258   *
259   * prompt_info is as before.  wrong_info is a description of the
260   * currently inserted token(s) so that the user is told what
261   * something is.  wrong_info, like prompt_info, may be null, but
262   * should not be an empty string.  Its contents should be
263   * syntactically similar to that of prompt_info.
264   */
265
266  /* Note that a single LoadKey operation might cause several calls to
267   * getpassphrase and/or requestphystoken.  If requestphystoken is
268   * not provided (ie, a null pointer is passed) then the plugin may
269   * not support loading keys for which authorisation by several cards
270   * is required.  If getpassphrase is not provided then cards with
271   * passphrases may not be supported.
272   *
273   * getpassphrase and getphystoken do not need to check that the
274   * passphrase has been entered correctly or the correct token
275   * inserted; the crypto plugin will do that.  If this is not the
276   * case then the crypto plugin is responsible for calling these
277   * routines again as appropriate until the correct token(s) and
278   * passphrase(s) are supplied as required, or until any retry limits
279   * implemented by the crypto plugin are reached.
280   *
281   * In either case, the application must allow the user to say `no'
282   * or `cancel' to indicate that they do not know the passphrase or
283   * have the appropriate token; this should cause the callback to
284   * return nonzero indicating error.
285   */
286
287  void (*logmessage)(void *logstream, const char *message);
288  /* A log message will be generated at least every time something goes
289   * wrong and an ErrMsgBuf is filled in (or would be if one was
290   * provided).  Other diagnostic information may be written there too,
291   * including more detailed reasons for errors which are reported in an
292   * ErrMsgBuf.
293   *
294   * When a log message is generated, this callback is called.  It
295   * should write a message to the relevant logging arrangements.
296   *
297   * The message string passed will be null-terminated and may be of arbitrary
298   * length.  It will not be prefixed by the time and date, nor by the
299   * name of the library that is generating it - if this is required,
300   * the logmessage callback must do it.  The message will not have a
301   * trailing newline (though it may contain internal newlines).
302   *
303   * If a null pointer is passed for logmessage a default function is
304   * used.  The default function treats logstream as a FILE* which has
305   * been converted to a void*.  If logstream is 0 it does nothing.
306   * Otherwise it prepends the date and time and library name and
307   * writes the message to logstream.  Each line will be prefixed by a
308   * descriptive string containing the date, time and identity of the
309   * crypto plugin.  Errors on the logstream are not reported
310   * anywhere, and the default function doesn't flush the stream, so
311   * the application must set the buffering how it wants it.
312   *
313   * The crypto plugin may also provide a facility to have copies of
314   * log messages sent elsewhere, and or for adjusting the verbosity
315   * of the log messages; any such facilities will be configured by
316   * external means.
317   */
318
319} HWCryptoHook_InitInfo;
320
321typedef
322HWCryptoHook_ContextHandle HWCryptoHook_Init_t(const HWCryptoHook_InitInfo *initinfo,
323                                               size_t initinfosize,
324                                               const HWCryptoHook_ErrMsgBuf *errors,
325                                               HWCryptoHook_CallerContext *cactx);
326extern HWCryptoHook_Init_t HWCryptoHook_Init;
327
328/* Caller should set initinfosize to the size of the HWCryptoHook struct,
329 * so it can be extended later.
330 *
331 * On success, a message for display or logging by the server,
332 * including the name and version number of the plugin, will be filled
333 * in into *errors; on failure *errors is used for error handling, as
334 * usual.
335 */
336
337/* All these functions return 0 on success, HWCRYPTOHOOK_ERROR_FAILED
338 * on most failures.  HWCRYPTOHOOK_ERROR_MPISIZE means at least one of
339 * the output MPI buffer(s) was too small; the sizes of all have been
340 * set to the desired size (and for those where the buffer was large
341 * enough, the value may have been copied in), and no error message
342 * has been recorded.
343 *
344 * You may pass 0 for the errors struct.  In any case, unless you set
345 * _NoStderr at init time then messages may be reported to stderr.
346 */
347
348/* The RSAImmed* functions (and key managed RSA) only work with
349 * modules which have an RSA patent licence - currently that means KM
350 * units; the ModExp* ones work with all modules, so you need a patent
351 * licence in the software in the US.  They are otherwise identical.
352 */
353
354typedef
355void HWCryptoHook_Finish_t(HWCryptoHook_ContextHandle hwctx);
356extern HWCryptoHook_Finish_t HWCryptoHook_Finish;
357/* You must not have any calls going or keys loaded when you call this. */
358
359typedef
360int HWCryptoHook_RandomBytes_t(HWCryptoHook_ContextHandle hwctx,
361                               unsigned char *buf, size_t len,
362                               const HWCryptoHook_ErrMsgBuf *errors);
363extern HWCryptoHook_RandomBytes_t HWCryptoHook_RandomBytes;
364
365typedef
366int HWCryptoHook_ModExp_t(HWCryptoHook_ContextHandle hwctx,
367                          HWCryptoHook_MPI a,
368                          HWCryptoHook_MPI p,
369                          HWCryptoHook_MPI n,
370                          HWCryptoHook_MPI *r,
371                          const HWCryptoHook_ErrMsgBuf *errors);
372extern HWCryptoHook_ModExp_t HWCryptoHook_ModExp;
373
374typedef
375int HWCryptoHook_RSAImmedPub_t(HWCryptoHook_ContextHandle hwctx,
376                               HWCryptoHook_MPI m,
377                               HWCryptoHook_MPI e,
378                               HWCryptoHook_MPI n,
379                               HWCryptoHook_MPI *r,
380                               const HWCryptoHook_ErrMsgBuf *errors);
381extern HWCryptoHook_RSAImmedPub_t HWCryptoHook_RSAImmedPub;
382
383typedef
384int HWCryptoHook_ModExpCRT_t(HWCryptoHook_ContextHandle hwctx,
385                             HWCryptoHook_MPI a,
386                             HWCryptoHook_MPI p,
387                             HWCryptoHook_MPI q,
388                             HWCryptoHook_MPI dmp1,
389                             HWCryptoHook_MPI dmq1,
390                             HWCryptoHook_MPI iqmp,
391                             HWCryptoHook_MPI *r,
392                             const HWCryptoHook_ErrMsgBuf *errors);
393extern HWCryptoHook_ModExpCRT_t HWCryptoHook_ModExpCRT;
394
395typedef
396int HWCryptoHook_RSAImmedPriv_t(HWCryptoHook_ContextHandle hwctx,
397                                HWCryptoHook_MPI m,
398                                HWCryptoHook_MPI p,
399                                HWCryptoHook_MPI q,
400                                HWCryptoHook_MPI dmp1,
401                                HWCryptoHook_MPI dmq1,
402                                HWCryptoHook_MPI iqmp,
403                                HWCryptoHook_MPI *r,
404                                const HWCryptoHook_ErrMsgBuf *errors);
405extern HWCryptoHook_RSAImmedPriv_t HWCryptoHook_RSAImmedPriv;
406
407/* The RSAImmed* and ModExp* functions may return E_FAILED or
408 * E_FALLBACK for failure.
409 *
410 * E_FAILED means the failure is permanent and definite and there
411 *    should be no attempt to fall back to software.  (Eg, for some
412 *    applications, which support only the acceleration-only
413 *    functions, the `key material' may actually be an encoded key
414 *    identifier, and doing the operation in software would give wrong
415 *    answers.)
416 *
417 * E_FALLBACK means that doing the computation in software would seem
418 *    reasonable.  If an application pays attention to this and is
419 *    able to fall back, it should also set the Fallback init flags.
420 */
421
422typedef
423int HWCryptoHook_RSALoadKey_t(HWCryptoHook_ContextHandle hwctx,
424                              const char *key_ident,
425                              HWCryptoHook_RSAKeyHandle *keyhandle_r,
426                              const HWCryptoHook_ErrMsgBuf *errors,
427                              HWCryptoHook_PassphraseContext *ppctx);
428extern HWCryptoHook_RSALoadKey_t HWCryptoHook_RSALoadKey;
429/* The key_ident is a null-terminated string configured by the
430 * user via the application's usual configuration mechanisms.
431 * It is provided to the user by the crypto provider's key management
432 * system.  The user must be able to enter at least any string of between
433 * 1 and 1023 characters inclusive, consisting of printable 7-bit
434 * ASCII characters.  The provider should avoid using
435 * any characters except alphanumerics and the punctuation
436 * characters  _ - + . / @ ~  (the user is expected to be able
437 * to enter these without quoting).  The string may be case-sensitive.
438 * The application may allow the user to enter other NULL-terminated strings,
439 * and the provider must cope (returning an error if the string is not
440 * valid).
441 *
442 * If the key does not exist, no error is recorded and 0 is returned;
443 * keyhandle_r will be set to 0 instead of to a key handle.
444 */
445
446typedef
447int HWCryptoHook_RSAGetPublicKey_t(HWCryptoHook_RSAKeyHandle k,
448                                   HWCryptoHook_MPI *n,
449                                   HWCryptoHook_MPI *e,
450                                   const HWCryptoHook_ErrMsgBuf *errors);
451extern HWCryptoHook_RSAGetPublicKey_t HWCryptoHook_RSAGetPublicKey;
452/* The crypto plugin will not store certificates.
453 *
454 * Although this function for acquiring the public key value is
455 * provided, it is not the purpose of this API to deal fully with the
456 * handling of the public key.
457 *
458 * It is expected that the crypto supplier's key generation program
459 * will provide general facilities for producing X.509
460 * self-certificates and certificate requests in PEM format.  These
461 * will be given to the user so that they can configure them in the
462 * application, send them to CAs, or whatever.
463 *
464 * In case this kind of certificate handling is not appropriate, the
465 * crypto supplier's key generation program should be able to be
466 * configured not to generate such a self-certificate or certificate
467 * request.  Then the application will need to do all of this, and
468 * will need to store and handle the public key and certificates
469 * itself.
470 */
471
472typedef
473int HWCryptoHook_RSAUnloadKey_t(HWCryptoHook_RSAKeyHandle k,
474                                const HWCryptoHook_ErrMsgBuf *errors);
475extern HWCryptoHook_RSAUnloadKey_t HWCryptoHook_RSAUnloadKey;
476/* Might fail due to locking problems, or other serious internal problems. */
477
478typedef
479int HWCryptoHook_RSA_t(HWCryptoHook_MPI m,
480                       HWCryptoHook_RSAKeyHandle k,
481                       HWCryptoHook_MPI *r,
482                       const HWCryptoHook_ErrMsgBuf *errors);
483extern HWCryptoHook_RSA_t HWCryptoHook_RSA;
484/* RSA private key operation (sign or decrypt) - raw, unpadded. */
485
486#endif /*HWCRYPTOHOOK_H*/
487