ffi_spake2p.cpp File Reference

#include <botan/ffi.h>
#include <botan/assert.h>
#include <botan/internal/ffi_rng.h>
#include <botan/internal/ffi_util.h>

Go to the source code of this file.

Functions
	BOTAN_FFI_DECLARE_DUMMY_STRUCT (botan_spake2p_params_struct, 0x2E1B4A96)
	BOTAN_FFI_DECLARE_DUMMY_STRUCT (botan_spake2p_prover_struct, 0x9F337C29)
	BOTAN_FFI_DECLARE_DUMMY_STRUCT (botan_spake2p_verifier_struct, 0xD70A9E13)
int	botan_spake2p_derive_secret (botan_spake2p_params_t params, const char *password, const uint8_t prover_id[], size_t prover_id_len, const uint8_t verifier_id[], size_t verifier_id_len, const uint8_t salt[], size_t salt_len, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_params_confirmation_size (botan_spake2p_params_t params, size_t *confirmation_size)
int	botan_spake2p_params_destroy (botan_spake2p_params_t params)
int	botan_spake2p_params_init (botan_spake2p_params_t *params, const char *ciphersuite)
int	botan_spake2p_params_init_custom (botan_spake2p_params_t *params, botan_ec_group_t group, const uint8_t seed[], size_t seed_len, const char *hash_fn)
int	botan_spake2p_params_share_size (botan_spake2p_params_t params, size_t *share_size)
int	botan_spake2p_prover_destroy (botan_spake2p_prover_t prover)
int	botan_spake2p_prover_generate_message (botan_spake2p_prover_t prover, botan_rng_t rng, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_prover_init (botan_spake2p_prover_t *prover, botan_spake2p_params_t params, const uint8_t secret[], size_t secret_len, const uint8_t prover_id[], size_t prover_id_len, const uint8_t verifier_id[], size_t verifier_id_len, const uint8_t context[], size_t context_len)
int	botan_spake2p_prover_process_message (botan_spake2p_prover_t prover, botan_rng_t rng, const uint8_t peer_message[], size_t peer_message_len, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_prover_shared_secret (botan_spake2p_prover_t prover, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_registration_record (botan_spake2p_params_t params, botan_rng_t rng, const uint8_t secret[], size_t secret_len, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_verifier_destroy (botan_spake2p_verifier_t verifier)
int	botan_spake2p_verifier_init (botan_spake2p_verifier_t *verifier, botan_spake2p_params_t params, const uint8_t record[], size_t record_len, const uint8_t prover_id[], size_t prover_id_len, const uint8_t verifier_id[], size_t verifier_id_len, const uint8_t context[], size_t context_len)
int	botan_spake2p_verifier_process_message (botan_spake2p_verifier_t verifier, botan_rng_t rng, const uint8_t peer_message[], size_t peer_message_len, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_verifier_shared_secret (botan_spake2p_verifier_t verifier, botan_view_ctx ctx, botan_view_bin_fn view)
int	botan_spake2p_verifier_skip_confirmation (botan_spake2p_verifier_t verifier)
int	botan_spake2p_verifier_verify_confirmation (botan_spake2p_verifier_t verifier, const uint8_t confirmation[], size_t confirmation_len)

Function Documentation

BOTAN_FFI_DECLARE_DUMMY_STRUCT() [1/3]

BOTAN_FFI_DECLARE_DUMMY_STRUCT	(	botan_spake2p_params_struct	,
		0x2E1B4A96	)

BOTAN_FFI_DECLARE_DUMMY_STRUCT() [2/3]

BOTAN_FFI_DECLARE_DUMMY_STRUCT	(	botan_spake2p_prover_struct	,
		0x9F337C29	)

BOTAN_FFI_DECLARE_DUMMY_STRUCT() [3/3]

BOTAN_FFI_DECLARE_DUMMY_STRUCT	(	botan_spake2p_verifier_struct	,
		0xD70A9E13	)

botan_spake2p_derive_secret()

int botan_spake2p_derive_secret	(	botan_spake2p_params_t	params,
		const char *	password,
		const uint8_t	prover_id[],
		size_t	prover_id_len,
		const uint8_t	verifier_id[],
		size_t	verifier_id_len,
		const uint8_t	salt[],
		size_t	salt_len,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Derive a SPAKE2+ prover secret (w0 and w1) from a password, using Argon2id

The view callback is invoked with the serialized prover secret, which is password equivalent and must be protected accordingly. It is used with botan_spake2p_registration_record and botan_spake2p_prover_init.

Parameters

params	the SPAKE2+ system parameters
password	the (null terminated) password
prover_id	the identity of the prover
prover_id_len	length of prover_id in bytes
verifier_id	the identity of the verifier
verifier_id_len	length of verifier_id in bytes
salt	a salt value, ideally random and stored with the registration record
salt_len	length of salt in bytes
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the serialized prover secret

Definition at line 137 of file ffi_spake2p.cpp.

                                                        {
   if(any_null_pointers(params, password)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return ffi_guard_thunk(__func__, [=]() -> int {
      const auto sec = Botan::SPAKE2p::ProverSecret::from_password(safe_get(params),
                                                                   password,
                                                                   spake2p_opt_span(prover_id, prover_id_len),
                                                                   spake2p_opt_span(verifier_id, verifier_id_len),
                                                                   spake2p_opt_span(salt, salt_len));
      return invoke_view_callback(view, ctx, sec.serialize());
   });
#else
   BOTAN_UNUSED(params, password, prover_id, prover_id_len, verifier_id, verifier_id_len);
   BOTAN_UNUSED(salt, salt_len, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_UNUSED, Botan_FFI::ffi_guard_thunk(), Botan::SPAKE2p::ProverSecret::from_password(), Botan_FFI::invoke_view_callback(), and Botan_FFI::safe_get().

botan_spake2p_params_confirmation_size()

int botan_spake2p_params_confirmation_size	(	botan_spake2p_params_t	params,
		size_t *	confirmation_size )

Return the size in bytes of a SPAKE2+ key confirmation message (confirmP or confirmV)

Parameters

params	the SPAKE2+ system parameters
confirmation_size	output parameter for the key confirmation size

Definition at line 121 of file ffi_spake2p.cpp.

                                                                                                     {
   if(any_null_pointers(params, confirmation_size)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(params, [=](const auto& p) -> int {
      *confirmation_size = p.confirmation_size();
      return BOTAN_FFI_SUCCESS;
   });
#else
   BOTAN_UNUSED(params, confirmation_size);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_FFI_SUCCESS, BOTAN_FFI_VISIT, and BOTAN_UNUSED.

botan_spake2p_params_destroy()

int botan_spake2p_params_destroy

(

botan_spake2p_params_t

params

)

Frees all resources of SPAKE2+ system parameters

Definition at line 102 of file ffi_spake2p.cpp.

                                                                {
   return BOTAN_FFI_CHECKED_DELETE(params);
}

References BOTAN_FFI_CHECKED_DELETE.

botan_spake2p_params_init()

int botan_spake2p_params_init	(	botan_spake2p_params_t *	params,
		const char *	ciphersuite )

Create SPAKE2+ system parameters from an RFC 9383 ciphersuite name

Objects created from the system parameters hold their own copy, so the parameters may be destroyed at any time.

Parameters

params	output parameter for the created system parameters
ciphersuite	the SPAKE2+ ciphersuite name

Definition at line 68 of file ffi_spake2p.cpp.

                                                                                       {
   if(any_null_pointers(params, ciphersuite)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return ffi_guard_thunk(__func__, [=]() -> int {
      *params = nullptr;
      auto p = std::make_unique<Botan::SPAKE2p::SystemParameters>(spake2p_params_from_name(ciphersuite));
      return ffi_new_object(params, std::move(p));
   });
#else
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, Botan_FFI::ffi_guard_thunk(), and Botan_FFI::ffi_new_object().

botan_spake2p_params_init_custom()

int botan_spake2p_params_init_custom	(	botan_spake2p_params_t *	params,
		botan_ec_group_t	group,
		const uint8_t	seed[],
		size_t	seed_len,
		const char *	hash_fn )

Create custom SPAKE2+ system parameters for an arbitrary group

The M/N group elements are derived from the seed using hash to curve; returns BOTAN_FFI_ERROR_NOT_IMPLEMENTED if the group does not support hash to curve. Both peers must use the same group, seed, and hash.

If the seed includes the identities of the participants, this additionally makes the scheme "quantum annoying", in that an attacker with a discrete logarithm oracle must compute a new discrete log for each (prover, verifier) pair they wish to attack.

Parameters

params	output parameter for the created system parameters
group	the elliptic curve group to use
SEED	the seed bytes used to derive the M/N group elements
seed_len	length of seed in bytes
hash_fn	the hash function to use (eg "SHA-256")

Definition at line 84 of file ffi_spake2p.cpp.

                                                                                                                       {
   if(any_null_pointers(params, group, hash_fn)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return ffi_guard_thunk(__func__, [=]() -> int {
      auto p = std::make_unique<Botan::SPAKE2p::SystemParameters>(
         Botan::SPAKE2p::SystemParameters::custom(safe_get(group), spake2p_opt_span(seed, seed_len), hash_fn));
      return ffi_new_object(params, std::move(p));
   });
#else
   BOTAN_UNUSED(params, group, seed, seed_len, hash_fn);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_UNUSED, Botan::SPAKE2p::SystemParameters::custom(), Botan_FFI::ffi_guard_thunk(), Botan_FFI::ffi_new_object(), and Botan_FFI::safe_get().

botan_spake2p_params_share_size()

int botan_spake2p_params_share_size	(	botan_spake2p_params_t	params,
		size_t *	share_size )

Return the size in bytes of a SPAKE2+ key share (shareP or shareV)

Parameters

params	the SPAKE2+ system parameters
share_size	output parameter for the key share size

Definition at line 106 of file ffi_spake2p.cpp.

                                                                                       {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(params, [=](const auto& p) -> int {
      if(share_size == nullptr) {
         return BOTAN_FFI_ERROR_NULL_POINTER;
      }
      *share_size = p.share_size();
      return BOTAN_FFI_SUCCESS;
   });
#else
   BOTAN_UNUSED(params, share_size);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_FFI_SUCCESS, BOTAN_FFI_VISIT, and BOTAN_UNUSED.

botan_spake2p_prover_destroy()

int botan_spake2p_prover_destroy

(

botan_spake2p_prover_t

prover

)

Frees all resources of a SPAKE2+ prover

Definition at line 221 of file ffi_spake2p.cpp.

                                                                {
   return BOTAN_FFI_CHECKED_DELETE(prover);
}

References BOTAN_FFI_CHECKED_DELETE.

botan_spake2p_prover_generate_message()

int botan_spake2p_prover_generate_message	(	botan_spake2p_prover_t	prover,
		botan_rng_t	rng,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Generate the prover's key share (shareP), which is sent to the verifier

This can be called only once per prover object.

Parameters

prover	the prover object
Random Number Generators	a random number generator
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the key share

Definition at line 225 of file ffi_spake2p.cpp.

                                                                  {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(
      prover, [=](auto& p) -> int { return invoke_view_callback(view, ctx, p.generate_message(safe_get(rng))); });
#else
   BOTAN_UNUSED(prover, rng, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_VISIT, BOTAN_UNUSED, Botan_FFI::invoke_view_callback(), and Botan_FFI::safe_get().

botan_spake2p_prover_init()

int botan_spake2p_prover_init	(	botan_spake2p_prover_t *	prover,
		botan_spake2p_params_t	params,
		const uint8_t	secret[],
		size_t	secret_len,
		const uint8_t	prover_id[],
		size_t	prover_id_len,
		const uint8_t	verifier_id[],
		size_t	verifier_id_len,
		const uint8_t	context[],
		size_t	context_len )

Initialize a SPAKE2+ prover

The identities and context must be agreed upon by both parties; the identities must additionally match the values used when deriving the prover secret.

Parameters

prover	output parameter for the created prover object
params	the SPAKE2+ system parameters
secret	the serialized prover secret
secret_len	length of secret in bytes
prover_id	the identity of the prover
prover_id_len	length of prover_id in bytes
verifier_id	the identity of the verifier
verifier_id_len	length of verifier_id in bytes
context	an application specific context string
context_len	length of context in bytes

Definition at line 188 of file ffi_spake2p.cpp.

                                                  {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   if(any_null_pointers(prover, params, secret)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
   return ffi_guard_thunk(__func__, [=]() -> int {
      *prover = nullptr;
      const auto& p = safe_get(params);
      const auto sec = Botan::SPAKE2p::ProverSecret::deserialize(p, {secret, secret_len});
      auto ctx = std::make_unique<Botan::SPAKE2p::ProverContext>(p,
                                                                 sec,
                                                                 spake2p_opt_span(prover_id, prover_id_len),
                                                                 spake2p_opt_span(verifier_id, verifier_id_len),
                                                                 spake2p_opt_span(context, context_len));
      return ffi_new_object(prover, std::move(ctx));
   });
#else
   BOTAN_UNUSED(prover, params, secret, secret_len, prover_id, prover_id_len);
   BOTAN_UNUSED(verifier_id, verifier_id_len, context, context_len);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_UNUSED, Botan::SPAKE2p::ProverSecret::deserialize(), Botan_FFI::ffi_guard_thunk(), Botan_FFI::ffi_new_object(), and Botan_FFI::safe_get().

botan_spake2p_prover_process_message()

int botan_spake2p_prover_process_message	(	botan_spake2p_prover_t	prover,
		botan_rng_t	rng,
		const uint8_t	peer_message[],
		size_t	peer_message_len,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Consume the verifier's response (shareV followed by confirmV) and produce the prover's key confirmation (confirmP), which is sent to the verifier.

Returns BOTAN_FFI_ERROR_BAD_MAC if the verifier's key confirmation is wrong, typically meaning the passwords do not match.

Parameters

prover	the prover object
Random Number Generators	a random number generator
peer_message	the verifier's response
peer_message_len	length of peer_message in bytes
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the prover's key confirmation

Definition at line 238 of file ffi_spake2p.cpp.

                                                                 {
   if(any_null_pointers(peer_message)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(prover, [=](auto& p) -> int {
      return invoke_view_callback(view, ctx, p.process_message({peer_message, peer_message_len}, safe_get(rng)));
   });
#else
   BOTAN_UNUSED(prover, rng, peer_message, peer_message_len, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_FFI_VISIT, BOTAN_UNUSED, Botan_FFI::invoke_view_callback(), and Botan_FFI::safe_get().

botan_spake2p_prover_shared_secret()

int botan_spake2p_prover_shared_secret	(	botan_spake2p_prover_t	prover,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Return the prover's shared secret (K_shared)

This may be called only after botan_spake2p_prover_process_message has succeeded.

Parameters

prover	the prover object
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the shared secret

Definition at line 257 of file ffi_spake2p.cpp.

                                                                                                                  {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(prover, [=](auto& p) -> int { return invoke_view_callback(view, ctx, p.shared_secret()); });
#else
   BOTAN_UNUSED(prover, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_VISIT, BOTAN_UNUSED, and Botan_FFI::invoke_view_callback().

botan_spake2p_registration_record()

int botan_spake2p_registration_record	(	botan_spake2p_params_t	params,
		botan_rng_t	rng,
		const uint8_t	secret[],
		size_t	secret_len,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Compute a SPAKE2+ registration record (w0 and L) from a prover secret

The registration record is provided to the verifier during registration. While it does not allow directly impersonating the prover, it does allow offline password guessing attacks, so it should be protected.

Parameters

params	the SPAKE2+ system parameters
Random Number Generators	a random number generator
secret	the serialized prover secret
secret_len	length of secret in bytes
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the serialized registration record

Definition at line 167 of file ffi_spake2p.cpp.

                                                              {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   if(any_null_pointers(params, rng, secret)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
   return ffi_guard_thunk(__func__, [=]() -> int {
      const auto sec = Botan::SPAKE2p::ProverSecret::deserialize(safe_get(params), {secret, secret_len});
      return invoke_view_callback(view, ctx, sec.registration_record(safe_get(rng)).serialize());
   });
#else
   BOTAN_UNUSED(params, rng, secret, secret_len, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_UNUSED, Botan::SPAKE2p::ProverSecret::deserialize(), Botan_FFI::ffi_guard_thunk(), Botan_FFI::invoke_view_callback(), and Botan_FFI::safe_get().

botan_spake2p_verifier_destroy()

int botan_spake2p_verifier_destroy

(

botan_spake2p_verifier_t

verifier

)

Frees all resources of a SPAKE2+ verifier

Definition at line 299 of file ffi_spake2p.cpp.

                                                                      {
   return BOTAN_FFI_CHECKED_DELETE(verifier);
}

References BOTAN_FFI_CHECKED_DELETE.

botan_spake2p_verifier_init()

int botan_spake2p_verifier_init	(	botan_spake2p_verifier_t *	verifier,
		botan_spake2p_params_t	params,
		const uint8_t	record[],
		size_t	record_len,
		const uint8_t	prover_id[],
		size_t	prover_id_len,
		const uint8_t	verifier_id[],
		size_t	verifier_id_len,
		const uint8_t	context[],
		size_t	context_len )

Initialize a SPAKE2+ verifier

The identities and context must be agreed upon by both parties; the identities must additionally match the values used when deriving the prover secret.

Parameters

verifier	output parameter for the created verifier object
params	the SPAKE2+ system parameters
record	the serialized registration record
record_len	length of record in bytes
prover_id	the identity of the prover
prover_id_len	length of prover_id in bytes
verifier_id	the identity of the verifier
verifier_id_len	length of verifier_id in bytes
context	an application specific context string
context_len	length of context in bytes

Definition at line 266 of file ffi_spake2p.cpp.

                                                    {
   if(any_null_pointers(verifier, record)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return ffi_guard_thunk(__func__, [=]() -> int {
      *verifier = nullptr;
      const auto& p = safe_get(params);
      const auto rec = Botan::SPAKE2p::RegistrationRecord::deserialize(p, {record, record_len});
      auto ctx = std::make_unique<Botan::SPAKE2p::VerifierContext>(p,
                                                                   rec,
                                                                   spake2p_opt_span(prover_id, prover_id_len),
                                                                   spake2p_opt_span(verifier_id, verifier_id_len),
                                                                   spake2p_opt_span(context, context_len));
      return ffi_new_object(verifier, std::move(ctx));
   });
#else
   BOTAN_UNUSED(verifier, params, record, record_len, prover_id, prover_id_len);
   BOTAN_UNUSED(verifier_id, verifier_id_len, context, context_len);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_UNUSED, Botan::SPAKE2p::RegistrationRecord::deserialize(), Botan_FFI::ffi_guard_thunk(), Botan_FFI::ffi_new_object(), and Botan_FFI::safe_get().

botan_spake2p_verifier_process_message()

int botan_spake2p_verifier_process_message	(	botan_spake2p_verifier_t	verifier,
		botan_rng_t	rng,
		const uint8_t	peer_message[],
		size_t	peer_message_len,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Consume the prover's key share (shareP) and produce the verifier's response (shareV followed by confirmV), which is sent to the prover.

This can be called only once per verifier object.

Parameters

verifier	the verifier object
Random Number Generators	a random number generator
peer_message	the prover's key share
peer_message_len	length of peer_message in bytes
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the verifier's response

Definition at line 303 of file ffi_spake2p.cpp.

                                                                   {
   if(any_null_pointers(peer_message)) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(verifier, [=](auto& v) -> int {
      return invoke_view_callback(view, ctx, v.process_message({peer_message, peer_message_len}, safe_get(rng)));
   });
#else
   BOTAN_UNUSED(verifier, rng, peer_message, peer_message_len, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References Botan_FFI::any_null_pointers(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_FFI_VISIT, BOTAN_UNUSED, Botan_FFI::invoke_view_callback(), and Botan_FFI::safe_get().

botan_spake2p_verifier_shared_secret()

int botan_spake2p_verifier_shared_secret	(	botan_spake2p_verifier_t	verifier,
		botan_view_ctx	ctx,
		botan_view_bin_fn	view )

Return the verifier's shared secret (K_shared)

This may be called only after botan_spake2p_verifier_verify_confirmation has succeeded, or after botan_spake2p_verifier_skip_confirmation.

Parameters

verifier	the verifier object
ctx	a context pointer passed to the view callback
view	a view callback which is invoked with the shared secret

Definition at line 353 of file ffi_spake2p.cpp.

                                                                 {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(verifier, [=](auto& v) -> int { return invoke_view_callback(view, ctx, v.shared_secret()); });
#else
   BOTAN_UNUSED(verifier, ctx, view);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_VISIT, BOTAN_UNUSED, and Botan_FFI::invoke_view_callback().

botan_spake2p_verifier_skip_confirmation()

int botan_spake2p_verifier_skip_confirmation

(

botan_spake2p_verifier_t

verifier

)

Skip checking the prover's key confirmation (confirmP)

This can be called after botan_spake2p_verifier_process_message, in place of botan_spake2p_verifier_verify_confirmation, to allow extracting the shared secret without having checked the prover's key confirmation.

Warning: after calling this, nothing is known about the peer; only a prover which knows the password can compute the same shared secret, but no evidence of this has been received. It is intended solely for protocols which embed SPAKE2+ and perform the prover's key confirmation themselves, for example the proposed TLS PAKE extension, where the TLS handshake takes the place of confirmP. Anywhere else, use botan_spake2p_verifier_verify_confirmation.

Parameters

verifier

the verifier object

Definition at line 341 of file ffi_spake2p.cpp.

                                                                                {
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(verifier, [](auto& v) -> int {
      v.skip_confirmation();
      return BOTAN_FFI_SUCCESS;
   });
#else
   BOTAN_UNUSED(verifier);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_SUCCESS, BOTAN_FFI_VISIT, and BOTAN_UNUSED.

botan_spake2p_verifier_verify_confirmation()

int botan_spake2p_verifier_verify_confirmation	(	botan_spake2p_verifier_t	verifier,
		const uint8_t	confirmation[],
		size_t	confirmation_len )

Check the prover's key confirmation (confirmP)

Returns BOTAN_FFI_ERROR_BAD_MAC if the confirmation is wrong, meaning the prover does not know the password.

Parameters

verifier	the verifier object
confirmation	the prover's key confirmation
confirmation_len	length of confirmation in bytes

Definition at line 323 of file ffi_spake2p.cpp.

                                                                        {
   if(confirmation == nullptr) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
#if defined(BOTAN_HAS_PAKE_SPAKE2PLUS)
   return BOTAN_FFI_VISIT(verifier, [=](auto& v) -> int {
      v.verify_confirmation({confirmation, confirmation_len});
      return BOTAN_FFI_SUCCESS;
   });
#else
   BOTAN_UNUSED(verifier, confirmation, confirmation_len);
   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
#endif
}

References BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_FFI_SUCCESS, BOTAN_FFI_VISIT, and BOTAN_UNUSED.