commit f6d42d45c5d8715b71654764c3927b687fc8ee30
author Treehugger Robot <treehugger-gerrit@google.com> Wed Nov 04 04:50:42 2020 +0000
committer Gerrit Code Review <noreply-gerritcodereview@google.com> Wed Nov 04 04:50:42 2020 +0000
tree 0820f69c1676246c0267bc45d2c0bbc6c8cdd30f
parent 65f4f4359dad0f7aee6abdc2cdd5e868111706db
parent 290b0ed4b37f2864873b0b64e83ea1875786898e

Merge changes I669a03a6,Ibb774d6d

* changes:
  libsnapshot: Fix footer values and verification
  libsnapshot: Fix some minor formatting bugs

fs_mgr/libsnapshot/cow_api_test.cpp

diff --git a/fs_mgr/libsnapshot/cow_api_test.cpp b/fs_mgr/libsnapshot/cow_api_test.cpp
index 3d0321f..1408244 100644
--- a/fs_mgr/libsnapshot/cow_api_test.cpp
+++ b/fs_mgr/libsnapshot/cow_api_test.cpp
@@ -272,7 +272,6 @@
 }
 
 TEST_F(CowTest, Append) {
-    cow_->DoNotRemove();
     CowOptions options;
     auto writer = std::make_unique<CowWriter>(options);
     ASSERT_TRUE(writer->Initialize(cow_->fd));

fs_mgr/libsnapshot/cow_reader.cpp

diff --git a/fs_mgr/libsnapshot/cow_reader.cpp b/fs_mgr/libsnapshot/cow_reader.cpp
index f10ccb6..452a5f3 100644
--- a/fs_mgr/libsnapshot/cow_reader.cpp
+++ b/fs_mgr/libsnapshot/cow_reader.cpp
@@ -154,7 +154,8 @@
             }
         } else if (current_op.type == kCowFooterOp) {
             memcpy(&footer_.op, &current_op, sizeof(footer_.op));
-
+            // we don't consider this an operation for the checksum
+            current_op_num--;
             if (android::base::ReadFully(fd_, &footer_.data, sizeof(footer_.data))) {
                 has_footer_ = true;
                 if (next_last_label) {
@@ -170,6 +171,19 @@
     memset(csum, 0, sizeof(uint8_t) * 32);
 
     if (has_footer_) {
+        if (ops_buffer->size() != footer_.op.num_ops) {
+            LOG(ERROR) << "num ops does not match";
+            return false;
+        }
+        if (ops_buffer->size() * sizeof(CowOperation) != footer_.op.ops_size) {
+            LOG(ERROR) << "ops size does not match ";
+            return false;
+        }
+        SHA256(&footer_.op, sizeof(footer_.op), footer_.data.footer_checksum);
+        if (memcmp(csum, footer_.data.ops_checksum, sizeof(csum)) != 0) {
+            LOG(ERROR) << "ops checksum does not match";
+            return false;
+        }
         SHA256(ops_buffer.get()->data(), footer_.op.ops_size, csum);
         if (memcmp(csum, footer_.data.ops_checksum, sizeof(csum)) != 0) {
             LOG(ERROR) << "ops checksum does not match";

fs_mgr/libsnapshot/cow_writer.cpp

diff --git a/fs_mgr/libsnapshot/cow_writer.cpp b/fs_mgr/libsnapshot/cow_writer.cpp
index ec2dc96..b3e75a0 100644
--- a/fs_mgr/libsnapshot/cow_writer.cpp
+++ b/fs_mgr/libsnapshot/cow_writer.cpp
@@ -185,6 +185,7 @@
     // Reset this, since we're going to reimport all operations.
     footer_.op.num_ops = 0;
     next_op_pos_ = sizeof(header_);
+    ops_.resize(0);
 
     auto iter = reader->GetOpIter();
     while (!iter->Done()) {
@@ -233,6 +234,7 @@
     // Reset this, since we're going to reimport all operations.
     footer_.op.num_ops = 0;
     next_op_pos_ = sizeof(header_);
+    ops_.resize(0);
 
     auto iter = reader->GetOpIter();
     while (!iter->Done()) {
@@ -247,7 +249,7 @@
     }
 
     if (!found_label) {
-        PLOG(ERROR) << "Failed to find last label";
+        LOG(ERROR) << "Failed to find last label";
         return false;
     }
 
@@ -384,7 +386,7 @@
 }
 
 bool CowWriter::Finalize() {
-    footer_.op.ops_size = ops_.size() + sizeof(footer_.op);
+    footer_.op.ops_size = ops_.size();
     uint64_t pos;
 
     if (!GetDataPos(&pos)) {

fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h

diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
index c031d63..0f47622 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
@@ -114,7 +114,6 @@
     bool OpenForWrite();
     bool OpenForAppend();
     bool OpenForAppend(uint64_t label);
-    bool ImportOps(std::unique_ptr<ICowOpIter> iter);
     bool GetDataPos(uint64_t* pos);
     bool WriteRawData(const void* data, size_t size);
     bool WriteOperation(const CowOperation& op, const void* data = nullptr, size_t size = 0);