added libgmp free calc ctr implementation to cipher

3 files changed, 56 insertions, 9 deletions

diff --git a/src/cipher.c b/src/cipher.c
index ff9e4e9..1a2a4fb 100644
--- a/src/cipher.c
+++ b/src/cipher.c
@@ -62,7 +62,7 @@ int cipher_init(cipher_t* c, const char* type)
   else if(!strncmp(type, "aes-ctr", 7)) {
     c->type_ = c_aes_ctr;
     if(type[7] == 0) {
-      c->key_length_ = 128;
+      c->key_length_ = C_AES_DEFAULT_KEY_LENGTH;
     }
     else if(type[7] != '-') 
       return -1;
@@ -202,7 +202,7 @@ int cipher_aesctr_init(cipher_t* c)
   if(c->salt_.buf_)
     free(c->salt_.buf_);
 
-  c->salt_.length_ = 14;
+  c->salt_.length_ = C_AES_CTR_LENGTH - C_AES_CTR_ZERO_LENGTH;
   c->salt_.buf_ = malloc(c->salt_.length_);
   if(!c->salt_.buf_)
     return -2;
@@ -216,18 +216,21 @@ int cipher_aesctr_init(cipher_t* c)
   cipher_aesctr_param_t* params = c->params_;
 
 #ifndef NO_LIBGMP
-  mpz_init2(params->mp_ctr, 128);
-  mpz_init2(params->mp_sid_mux, 128);
-  mpz_init2(params->mp_seq, 128);
-#endif
+  mpz_init2(params->mp_ctr, C_AES_CTR_LENGTH * 8);
+  mpz_init2(params->mp_sid_mux, C_AES_CTR_LENGTH * 8);
+  mpz_init2(params->mp_seq, C_AES_CTR_LENGTH * 8);
 
-  params->ctr_.length_ = 16;
+  params->ctr_.length_ = C_AES_CTR_LENGTH;
   params->ctr_.buf_ = malloc(params->ctr_.length_);
   if(!params->ctr_.buf_) {
     free(c->params_);
     c->params_ = NULL;
     return -2;
   }
+#else
+  params->ctr_.length_ = C_AES_CTR_LENGTH;
+  params->ctr_.buf_ = params->ctr_.ctr_.buf_;
+#endif
 
 
   int algo;
@@ -261,9 +264,10 @@ void cipher_aesctr_close(cipher_t* c)
     mpz_clear(params->mp_ctr);
     mpz_clear(params->mp_sid_mux);
     mpz_clear(params->mp_seq);
-#endif
+
     if(params->ctr_.buf_)
       free(params->ctr_.buf_);
+#endif
 
     if(params->handle_)
       gcry_cipher_close(params->handle_);
@@ -312,6 +316,16 @@ int cipher_aesctr_calc_ctr(cipher_t* c, key_derivation_t* kd, seq_nr_t seq_nr, s
     return -1;
   }
   mpz_export(params->ctr_.buf_, NULL, 1, 1, 0, 0, params->mp_ctr);
+#else
+  if(c->salt_.length_ != sizeof(params->ctr_.ctr_.salt_.buf_)) {
+    log_printf(ERR, "cipher salt has the wrong length");
+    return -1;
+  }
+  memcpy(params->ctr_.ctr_.salt_.buf_, c->salt_.buf_, sizeof(params->ctr_.ctr_.salt_.buf_));
+  memset(params->ctr_.ctr_.salt_.zero_, 0, sizeof(params->ctr_.ctr_.salt_.zero_));
+  params->ctr_.ctr_.params_.mux_ ^= MUX_T_HTON(mux);
+  params->ctr_.ctr_.params_.sender_id_ ^= SENDER_ID_T_HTON(sender_id);
+  params->ctr_.ctr_.params_.seq_nr_ ^= SEQ_NR_T_HTON(seq_nr);
 #endif
 
 #ifndef ANYTUN_02_COMPAT
diff --git a/src/cipher.h b/src/cipher.h
index 137540b..3e172a2 100644
--- a/src/cipher.h
+++ b/src/cipher.h
@@ -64,13 +64,45 @@ int32_t cipher_null_crypt(u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t
 
 
 #ifndef NO_CRYPT
+
+#define C_AES_DEFAULT_KEY_LENGTH 128
+#define C_AES_CTR_LENGTH 16
+#define C_AES_CTR_ZERO_LENGTH 2
+#ifdef NO_LIBGMP
+union __attribute__ ((__packed__)) cipher_aesctr_ctr_buf_union {
+  u_int8_t buf_[C_AES_CTR_LENGTH];
+  struct __attribute__ ((__packed__)) {
+    u_int8_t buf_[C_AES_CTR_LENGTH - C_AES_CTR_ZERO_LENGTH];
+    u_int8_t zero_[C_AES_CTR_ZERO_LENGTH];
+  } salt_;
+  struct __attribute__ ((__packed__)) {
+    u_int8_t fill_[C_AES_CTR_LENGTH - sizeof(mux_t) - sizeof(sender_id_t) - 2 - sizeof(seq_nr_t) - C_AES_CTR_ZERO_LENGTH];
+    mux_t mux_;
+    sender_id_t sender_id_;
+    u_int8_t empty_[2];
+    seq_nr_t seq_nr_;
+    u_int8_t zero_[C_AES_CTR_ZERO_LENGTH];
+  } params_;
+};
+typedef union cipher_aesctr_ctr_buf_union cipher_aesctr_ctr_buf_t;
+
+struct cipher_aesctr_ctr_struct {
+  u_int32_t length_;
+  u_int8_t* buf_;
+  cipher_aesctr_ctr_buf_t ctr_;
+};
+typedef struct cipher_aesctr_ctr_struct cipher_aesctr_ctr_t;
+#endif
+
 struct cipher_aesctr_param_struct {
   gcry_cipher_hd_t handle_;
-  buffer_t ctr_;
 #ifndef NO_LIBGMP
+  buffer_t ctr_;
   mpz_t mp_ctr;
   mpz_t mp_sid_mux;
   mpz_t mp_seq;
+#else
+  cipher_aesctr_ctr_t ctr_;
 #endif
 };
 typedef struct cipher_aesctr_param_struct cipher_aesctr_param_t;
diff --git a/src/key_derivation.c b/src/key_derivation.c
index eaf80e5..db139ad 100644
--- a/src/key_derivation.c
+++ b/src/key_derivation.c
@@ -228,6 +228,7 @@ void key_derivation_aesctr_close(key_derivation_t* kd)
 #ifndef NO_LIBGMP
     mpz_clear(params->mp_ctr);
     mpz_clear(params->mp_key_id);
+
     if(params->ctr_.buf_)
       free(params->ctr_.buf_);
 #endif