Avoid throwing within the FFI layer

No reason given we know the message is going to be thrown away.

3 files changed, 9 insertions, 10 deletions

diff --git a/src/lib/ffi/ffi_kdf.cpp b/src/lib/ffi/ffi_kdf.cpp
index 479bf2140..c63406625 100644
--- a/src/lib/ffi/ffi_kdf.cpp
+++ b/src/lib/ffi/ffi_kdf.cpp
@@ -91,7 +91,7 @@ int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
          return BOTAN_FFI_ERROR_BAD_FLAG;
 
       if(wf < 4 || wf > 18)
-         throw FFI_Error("Bad bcrypt work factor " + std::to_string(wf), BOTAN_FFI_ERROR_BAD_PARAMETER);
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
 
       Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
       const std::string bcrypt = Botan::generate_bcrypt(pass, rng, static_cast<uint16_t>(wf));
diff --git a/src/lib/ffi/ffi_pkey_algs.cpp b/src/lib/ffi/ffi_pkey_algs.cpp
index 622da7a14..7987639c8 100644
--- a/src/lib/ffi/ffi_pkey_algs.cpp
+++ b/src/lib/ffi/ffi_pkey_algs.cpp
@@ -117,7 +117,7 @@ Botan::BigInt pubkey_get_field(const Botan::Public_Key& key,
       else if(field == "e")
          return rsa->get_e();
       else
-         throw Botan::Exception("Field not supported");
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
       }
 #endif
 
@@ -134,7 +134,7 @@ Botan::BigInt pubkey_get_field(const Botan::Public_Key& key,
       else if(field == "y")
          return dl->get_y();
       else
-         throw Botan::Exception("Field not supported");
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
       }
 #endif
 
@@ -160,12 +160,12 @@ Botan::BigInt pubkey_get_field(const Botan::Public_Key& key,
       else if(field == "order")
          return ecc->domain().get_order();
       else
-         throw Botan::Exception("Field not supported");
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
       }
 #endif
 
    // Some other algorithm type not supported by this function
-   throw Botan::Exception("Unsupported algorithm type for botan_pubkey_get_field");
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
    }
 
 Botan::BigInt privkey_get_field(const Botan::Private_Key& key,
@@ -216,7 +216,7 @@ Botan::BigInt privkey_get_field(const Botan::Private_Key& key,
 #endif
 
    // Some other algorithm type not supported by this function
-   throw Botan::Exception("Unsupported algorithm type for botan_privkey_get_field");
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
    }
 
 }
diff --git a/src/lib/ffi/ffi_util.h b/src/lib/ffi/ffi_util.h
index 2b9206f0b..684b25870 100644
--- a/src/lib/ffi/ffi_util.h
+++ b/src/lib/ffi/ffi_util.h
@@ -63,11 +63,10 @@ T& safe_get(botan_struct<T,M>* p)
    if(p->magic_ok() == false)
       throw FFI_Error("Bad magic in ffi object", BOTAN_FFI_ERROR_INVALID_OBJECT);
 
-   T* t = p->unsafe_get();
-   if(t)
+   if(T* t = p->unsafe_get())
       return *t;
-   else
-      throw FFI_Error("Invalid object pointer", BOTAN_FFI_ERROR_INVALID_OBJECT);
+
+   throw FFI_Error("Invalid object pointer", BOTAN_FFI_ERROR_INVALID_OBJECT);
    }
 
 int ffi_guard_thunk(const char* func_name, std::function<int ()>);