commit 00aa794186c2e2f2b8366a39b7c3f40a72467f34
author Shawn Willden <swillden@google.com> Wed Sep 10 07:57:43 2014 -0600
committer Shawn Willden <swillden@google.com> Wed Sep 10 08:07:29 2014 -0600
tree 8eba8cab1e815749731aa4ed448c2eb126340140
parent 2b3bbf8d918010de02cbf5b6093cda8bcd812ffe

Remove message size checks for RSA and DSA signing operations.

There appears to be too much code, both production and tests, that
assumes it can feed various-sized messages to signing ops.  This change
essentially just falls back on openssl, letting it decide what is
acceptable and what is not.  That should make it bug-compatible with
softkeymaster, and perhaps with other TEE implementations.

Change-Id: I6185fdef3abf19321029d0b192669b722b363cf8

dsa_operation.cpp

diff --git a/dsa_operation.cpp b/dsa_operation.cpp
index c2e0fb1..dc64343 100644
--- a/dsa_operation.cpp
+++ b/dsa_operation.cpp
@@ -45,9 +45,6 @@
 
 keymaster_error_t DsaSignOperation::Finish(const Buffer& /* signature */, Buffer* output) {
     output->Reinitialize(DSA_size(dsa_key_));
-    if (data_.available_read() != output->buffer_size())
-        return KM_ERROR_INVALID_INPUT_LENGTH;
-
     unsigned int siglen;
     if (!DSA_sign(0 /* type -- ignored */, data_.peek_read(), data_.available_read(),
                   output->peek_write(), &siglen, dsa_key_))

google_keymaster_test.cpp

diff --git a/google_keymaster_test.cpp b/google_keymaster_test.cpp
index a492743..18befde 100644
--- a/google_keymaster_test.cpp
+++ b/google_keymaster_test.cpp
@@ -657,7 +657,7 @@
     finish_request.op_handle = begin_response.op_handle;
     FinishOperationResponse finish_response;
     device.FinishOperation(finish_request, &finish_response);
-    ASSERT_EQ(KM_ERROR_INVALID_INPUT_LENGTH, finish_response.error);
+    ASSERT_EQ(KM_ERROR_UNKNOWN_ERROR, finish_response.error);
     EXPECT_EQ(0U, finish_response.output.available_read());
 
     EXPECT_EQ(KM_ERROR_INVALID_OPERATION_HANDLE, device.AbortOperation(begin_response.op_handle));

rsa_operation.cpp

diff --git a/rsa_operation.cpp b/rsa_operation.cpp
index 816c234..4eef5c1 100644
--- a/rsa_operation.cpp
+++ b/rsa_operation.cpp
@@ -50,9 +50,6 @@
 
 keymaster_error_t RsaSignOperation::Finish(const Buffer& /* signature */, Buffer* output) {
     output->Reinitialize(RSA_size(rsa_key_));
-    if (data_.available_read() != output->buffer_size())
-        return KM_ERROR_INVALID_INPUT_LENGTH;
-
     int bytes_encrypted = RSA_private_encrypt(data_.available_read(), data_.peek_read(),
                                               output->peek_write(), rsa_key_, RSA_NO_PADDING);
     if (bytes_encrypted < 0)