diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/libcharon/sa/keymat_v2.c | 6 | ||||
| -rw-r--r-- | src/libstrongswan/crypto/prf_plus.c | 89 | ||||
| -rw-r--r-- | src/libstrongswan/crypto/prf_plus.h | 22 |
3 files changed, 51 insertions, 66 deletions
diff --git a/src/libcharon/sa/keymat_v2.c b/src/libcharon/sa/keymat_v2.c index 9fd17328f..e8081cba0 100644 --- a/src/libcharon/sa/keymat_v2.c +++ b/src/libcharon/sa/keymat_v2.c @@ -316,7 +316,7 @@ METHOD(keymat_v2_t, derive_ike_keys, bool, this->prf->set_key(this->prf, fixed_nonce); this->prf->allocate_bytes(this->prf, secret, &skeyseed); this->prf->set_key(this->prf, skeyseed); - prf_plus = prf_plus_create(this->prf, prf_plus_seed); + prf_plus = prf_plus_create(this->prf, TRUE, prf_plus_seed); } else { @@ -336,7 +336,7 @@ METHOD(keymat_v2_t, derive_ike_keys, bool, rekey_prf->set_key(rekey_prf, rekey_skd); rekey_prf->allocate_bytes(rekey_prf, secret, &skeyseed); rekey_prf->set_key(rekey_prf, skeyseed); - prf_plus = prf_plus_create(rekey_prf, prf_plus_seed); + prf_plus = prf_plus_create(rekey_prf, TRUE, prf_plus_seed); } DBG4(DBG_IKE, "SKEYSEED %B", &skeyseed); @@ -503,7 +503,7 @@ METHOD(keymat_v2_t, derive_child_keys, bool, } this->prf->set_key(this->prf, this->skd); - prf_plus = prf_plus_create(this->prf, seed); + prf_plus = prf_plus_create(this->prf, TRUE, seed); prf_plus->allocate_bytes(prf_plus, enc_size, encr_i); prf_plus->allocate_bytes(prf_plus, int_size, integ_i); diff --git a/src/libstrongswan/crypto/prf_plus.c b/src/libstrongswan/crypto/prf_plus.c index 8e815e608..d932d86b2 100644 --- a/src/libstrongswan/crypto/prf_plus.c +++ b/src/libstrongswan/crypto/prf_plus.c @@ -25,6 +25,7 @@ typedef struct private_prf_plus_t private_prf_plus_t; * */ struct private_prf_plus_t { + /** * Public interface of prf_plus_t. */ @@ -48,42 +49,43 @@ struct private_prf_plus_t { /** * Already given out bytes in current buffer. */ - size_t given_out; + size_t used; /** - * Octet which will be appended to the seed. + * Octet which will be appended to the seed, 0 if not used */ - u_int8_t appending_octet; + u_int8_t counter; }; METHOD(prf_plus_t, get_bytes, void, private_prf_plus_t *this, size_t length, u_int8_t *buffer) { - chunk_t appending_chunk; - size_t bytes_in_round; - size_t total_bytes_written = 0; - - appending_chunk.ptr = &(this->appending_octet); - appending_chunk.len = 1; + size_t round, written = 0; while (length > 0) - { /* still more to do... */ - if (this->buffer.len == this->given_out) - { /* no bytes left in buffer, get next*/ + { + if (this->buffer.len == this->used) + { /* buffer used, get next round */ this->prf->get_bytes(this->prf, this->buffer, NULL); - this->prf->get_bytes(this->prf, this->seed, NULL); - this->prf->get_bytes(this->prf, appending_chunk, this->buffer.ptr); - this->given_out = 0; - this->appending_octet++; + if (this->counter) + { + this->prf->get_bytes(this->prf, this->seed, NULL); + this->prf->get_bytes(this->prf, chunk_from_thing(this->counter), + this->buffer.ptr); + } + else + { + this->prf->get_bytes(this->prf, this->seed, this->buffer.ptr); + } + this->counter++; + this->used = 0; } - /* how many bytes can we write in this round ? */ - bytes_in_round = min(length, this->buffer.len - this->given_out); - /* copy bytes from buffer with offset */ - memcpy(buffer + total_bytes_written, this->buffer.ptr + this->given_out, bytes_in_round); - - length -= bytes_in_round; - this->given_out += bytes_in_round; - total_bytes_written += bytes_in_round; + round = min(length, this->buffer.len - this->used); + memcpy(buffer + written, this->buffer.ptr + this->used, round); + + length -= round; + this->used += round; + written += round; } } @@ -92,8 +94,7 @@ METHOD(prf_plus_t, allocate_bytes, void, { if (length) { - chunk->ptr = malloc(length); - chunk->len = length; + *chunk = chunk_alloc(length); get_bytes(this, length, chunk->ptr); } else @@ -113,10 +114,9 @@ METHOD(prf_plus_t, destroy, void, /* * Description in header. */ -prf_plus_t *prf_plus_create(prf_t *prf, chunk_t seed) +prf_plus_t *prf_plus_create(prf_t *prf, bool counter, chunk_t seed) { private_prf_plus_t *this; - chunk_t appending_chunk; INIT(this, .public = { @@ -125,25 +125,22 @@ prf_plus_t *prf_plus_create(prf_t *prf, chunk_t seed) .destroy = _destroy, }, .prf = prf, + .buffer = chunk_alloc(prf->get_block_size(prf)), + .seed = chunk_clone(seed), ); - /* allocate buffer for prf output */ - this->buffer.len = prf->get_block_size(prf); - this->buffer.ptr = malloc(this->buffer.len); - - this->appending_octet = 0x01; - - /* clone seed */ - this->seed.ptr = clalloc(seed.ptr, seed.len); - this->seed.len = seed.len; - - /* do the first run */ - appending_chunk.ptr = &(this->appending_octet); - appending_chunk.len = 1; - this->prf->get_bytes(this->prf, this->seed, NULL); - this->prf->get_bytes(this->prf, appending_chunk, this->buffer.ptr); - this->given_out = 0; - this->appending_octet++; + if (counter) + { + this->counter = 0x01; + this->prf->get_bytes(this->prf, this->seed, NULL); + this->prf->get_bytes(this->prf, chunk_from_thing(this->counter), + this->buffer.ptr); + this->counter++; + } + else + { + this->prf->get_bytes(this->prf, this->seed, this->buffer.ptr); + } - return &(this->public); + return &this->public; } diff --git a/src/libstrongswan/crypto/prf_plus.h b/src/libstrongswan/crypto/prf_plus.h index 4179f2695..668f12c02 100644 --- a/src/libstrongswan/crypto/prf_plus.h +++ b/src/libstrongswan/crypto/prf_plus.h @@ -27,19 +27,13 @@ typedef struct prf_plus_t prf_plus_t; #include <crypto/prfs/prf.h> /** - * Implementation of the prf+ function described in IKEv2 RFC. - * - * This class implements the prf+ algorithm. Internally it uses a pseudo random - * function, which implements the prf_t interface. - * See IKEv2 RFC 2.13. + * Implementation of the prf+ function used in IKEv1/IKEv2 keymat extension. */ struct prf_plus_t { + /** * Get pseudo random bytes. * - * Get the next few bytes of the prf+ output. Space - * must be allocated by the caller. - * * @param length number of bytes to get * @param buffer pointer where the generated bytes will be written */ @@ -48,9 +42,6 @@ struct prf_plus_t { /** * Allocate pseudo random bytes. * - * Get the next few bytes of the prf+ output. This function - * will allocate the required space. - * * @param length number of bytes to get * @param chunk chunk which will hold generated bytes */ @@ -65,14 +56,11 @@ struct prf_plus_t { /** * Creates a new prf_plus_t object. * - * Seed will be cloned. prf will - * not be cloned, must be destroyed outside after - * prf_plus_t usage. - * - * @param prf prf object to use + * @param prf prf object to use, must be destroyd after prf+. + * @param counter use an appending counter byte (for IKEv2 variant) * @param seed input seed for prf * @return prf_plus_t object */ -prf_plus_t *prf_plus_create(prf_t *prf, chunk_t seed); +prf_plus_t *prf_plus_create(prf_t *prf, bool counter, chunk_t seed); #endif /** PRF_PLUS_H_ @}*/ |