diff options
Diffstat (limited to 'pkg/merkletree')
-rw-r--r-- | pkg/merkletree/merkletree.go | 224 | ||||
-rw-r--r-- | pkg/merkletree/merkletree_test.go | 175 |
2 files changed, 323 insertions, 76 deletions
diff --git a/pkg/merkletree/merkletree.go b/pkg/merkletree/merkletree.go index 4b4f9bd52..a6e698f57 100644 --- a/pkg/merkletree/merkletree.go +++ b/pkg/merkletree/merkletree.go @@ -41,7 +41,7 @@ type Layout struct { blockSize int64 // digestSize is the size of a generated hash. digestSize int64 - // levelOffset contains the offset of the begnning of each level in + // levelOffset contains the offset of the beginning of each level in // bytes. The number of levels in the tree is the length of the slice. // The leaf nodes (level 0) contain hashes of blocks of the input data. // Each level N contains hashes of the blocks in level N-1. The highest @@ -123,45 +123,87 @@ func (layout Layout) blockOffset(level int, index int64) int64 { return layout.levelOffset[level] + index*layout.blockSize } +// VerityDescriptor is a struct that is serialized and hashed to get a file's +// root hash, which contains the root hash of the raw content and the file's +// meatadata. +type VerityDescriptor struct { + Name string + Mode uint32 + UID uint32 + GID uint32 + RootHash []byte +} + +func (d *VerityDescriptor) String() string { + return fmt.Sprintf("Name: %s, Mode: %d, UID: %d, GID: %d, RootHash: %v", d.Name, d.Mode, d.UID, d.GID, d.RootHash) +} + +// GenerateParams contains the parameters used to generate a Merkle tree. +type GenerateParams struct { + // File is a reader of the file to be hashed. + File io.ReadSeeker + // Size is the size of the file. + Size int64 + // Name is the name of the target file. + Name string + // Mode is the mode of the target file. + Mode uint32 + // UID is the user ID of the target file. + UID uint32 + // GID is the group ID of the target file. + GID uint32 + // TreeReader is a reader for the Merkle tree. + TreeReader io.ReadSeeker + // TreeWriter is a writer for the Merkle tree. + TreeWriter io.WriteSeeker + // DataAndTreeInSameFile is true if data and Merkle tree are in the same + // file, or false if Merkle tree is a separate file from data. + DataAndTreeInSameFile bool +} + // Generate constructs a Merkle tree for the contents of data. The output is // written to treeWriter. The treeReader should be able to read the tree after // it has been written. That is, treeWriter and treeReader should point to the // same underlying data but have separate cursors. +// +// Generate returns a hash of descriptor. The descriptor contains the file +// metadata and the hash from file content. +// // Generate will modify the cursor for data, but always restores it to its // original position upon exit. The cursor for tree is modified and not // restored. -func Generate(data io.ReadSeeker, dataSize int64, treeReader io.ReadSeeker, treeWriter io.WriteSeeker, dataAndTreeInSameFile bool) ([]byte, error) { - layout := InitLayout(dataSize, dataAndTreeInSameFile) +func Generate(params *GenerateParams) ([]byte, error) { + layout := InitLayout(params.Size, params.DataAndTreeInSameFile) - numBlocks := (dataSize + layout.blockSize - 1) / layout.blockSize + numBlocks := (params.Size + layout.blockSize - 1) / layout.blockSize // If the data is in the same file as the tree, zero pad the last data // block. - bytesInLastBlock := dataSize % layout.blockSize - if dataAndTreeInSameFile && bytesInLastBlock != 0 { + bytesInLastBlock := params.Size % layout.blockSize + if params.DataAndTreeInSameFile && bytesInLastBlock != 0 { zeroBuf := make([]byte, layout.blockSize-bytesInLastBlock) - if _, err := treeWriter.Seek(0, io.SeekEnd); err != nil && err != io.EOF { + if _, err := params.TreeWriter.Seek(0, io.SeekEnd); err != nil && err != io.EOF { return nil, err } - if _, err := treeWriter.Write(zeroBuf); err != nil { + if _, err := params.TreeWriter.Write(zeroBuf); err != nil { return nil, err } } // Store the current offset, so we can set it back once verification // finishes. - origOffset, err := data.Seek(0, io.SeekCurrent) + origOffset, err := params.File.Seek(0, io.SeekCurrent) if err != nil { return nil, err } - defer data.Seek(origOffset, io.SeekStart) + defer params.File.Seek(origOffset, io.SeekStart) // Read from the beginning of both data and treeReader. - if _, err := data.Seek(0, io.SeekStart); err != nil && err != io.EOF { + if _, err := params.File.Seek(0, io.SeekStart); err != nil && err != io.EOF { return nil, err } - if _, err := treeReader.Seek(0, io.SeekStart); err != nil && err != io.EOF { + if _, err := params.TreeReader.Seek(0, io.SeekStart); err != nil && err != io.EOF { return nil, err } @@ -176,11 +218,11 @@ func Generate(data io.ReadSeeker, dataSize int64, treeReader io.ReadSeeker, tree if level == 0 { // Read data block from the target file since level 0 includes hashes // of blocks in the input data. - n, err = data.Read(buf) + n, err = params.File.Read(buf) } else { // Read data block from the tree file since levels higher than 0 are // hashing the lower level hashes. - n, err = treeReader.Read(buf) + n, err = params.TreeReader.Read(buf) } // err is populated as long as the bytes read is smaller than the buffer @@ -200,7 +242,7 @@ func Generate(data io.ReadSeeker, dataSize int64, treeReader io.ReadSeeker, tree } // Write the generated hash to the end of the tree file. - if _, err = treeWriter.Write(digest[:]); err != nil { + if _, err = params.TreeWriter.Write(digest[:]); err != nil { return nil, err } } @@ -208,45 +250,124 @@ func Generate(data io.ReadSeeker, dataSize int64, treeReader io.ReadSeeker, tree // remaining of the last block. But no need to do so for root. if level != layout.rootLevel() && numBlocks%layout.hashesPerBlock() != 0 { zeroBuf := make([]byte, layout.blockSize-(numBlocks%layout.hashesPerBlock())*layout.digestSize) - if _, err := treeWriter.Write(zeroBuf[:]); err != nil { + if _, err := params.TreeWriter.Write(zeroBuf[:]); err != nil { return nil, err } } numBlocks = (numBlocks + layout.hashesPerBlock() - 1) / layout.hashesPerBlock() } - return root, nil + descriptor := VerityDescriptor{ + Name: params.Name, + Mode: params.Mode, + UID: params.UID, + GID: params.GID, + RootHash: root, + } + ret := sha256.Sum256([]byte(descriptor.String())) + return ret[:], nil +} + +// VerifyParams contains the params used to verify a portion of a file against +// a Merkle tree. +type VerifyParams struct { + // Out will be filled with verified data. + Out io.Writer + // File is a handler on the file to be verified. + File io.ReadSeeker + // tree is a handler on the Merkle tree used to verify file. + Tree io.ReadSeeker + // Size is the size of the file. + Size int64 + // Name is the name of the target file. + Name string + // Mode is the mode of the target file. + Mode uint32 + // UID is the user ID of the target file. + UID uint32 + // GID is the group ID of the target file. + GID uint32 + // ReadOffset is the offset of the data range to be verified. + ReadOffset int64 + // ReadSize is the size of the data range to be verified. + ReadSize int64 + // ExpectedRoot is a trusted hash for the file. It is compared with the + // calculated root hash to verify the content. + ExpectedRoot []byte + // DataAndTreeInSameFile is true if data and Merkle tree are in the same + // file, or false if Merkle tree is a separate file from data. + DataAndTreeInSameFile bool +} + +// verifyDescriptor generates a hash from descriptor, and compares it with +// expectedRoot. +func verifyDescriptor(descriptor VerityDescriptor, expectedRoot []byte) error { + h := sha256.Sum256([]byte(descriptor.String())) + if !bytes.Equal(h[:], expectedRoot) { + return fmt.Errorf("unexpected root hash") + } + return nil +} + +// verifyMetadata verifies the metadata by hashing a descriptor that contains +// the metadata and compare the generated hash with expectedRoot. +// +// For verifyMetadata, params.data is not needed. It only accesses params.tree +// for the raw root hash. +func verifyMetadata(params *VerifyParams, layout Layout) error { + if _, err := params.Tree.Seek(layout.blockOffset(layout.rootLevel(), 0 /* index */), io.SeekStart); err != nil { + return fmt.Errorf("failed to seek to root hash: %w", err) + } + root := make([]byte, layout.digestSize) + if _, err := params.Tree.Read(root); err != nil { + return fmt.Errorf("failed to read root hash: %w", err) + } + descriptor := VerityDescriptor{ + Name: params.Name, + Mode: params.Mode, + UID: params.UID, + GID: params.GID, + RootHash: root, + } + return verifyDescriptor(descriptor, params.ExpectedRoot) } // Verify verifies the content read from data with offset. The content is // verified against tree. If content spans across multiple blocks, each block is // verified. Verification fails if the hash of the data does not match the tree // at any level, or if the final root hash does not match expectedRoot. -// Once the data is verified, it will be written using w. +// Once the data is verified, it will be written using params.Out. +// +// Verify checks for both target file content and metadata. If readSize is 0, +// only metadata is checked. +// // Verify will modify the cursor for data, but always restores it to its // original position upon exit. The cursor for tree is modified and not // restored. -func Verify(w io.Writer, data, tree io.ReadSeeker, dataSize int64, readOffset int64, readSize int64, expectedRoot []byte, dataAndTreeInSameFile bool) (int64, error) { - if readSize <= 0 { - return 0, fmt.Errorf("Unexpected read size: %d", readSize) +func Verify(params *VerifyParams) (int64, error) { + if params.ReadSize < 0 { + return 0, fmt.Errorf("unexpected read size: %d", params.ReadSize) + } + layout := InitLayout(int64(params.Size), params.DataAndTreeInSameFile) + if params.ReadSize == 0 { + return 0, verifyMetadata(params, layout) } - layout := InitLayout(int64(dataSize), dataAndTreeInSameFile) // Calculate the index of blocks that includes the target range in input // data. - firstDataBlock := readOffset / layout.blockSize - lastDataBlock := (readOffset + readSize - 1) / layout.blockSize + firstDataBlock := params.ReadOffset / layout.blockSize + lastDataBlock := (params.ReadOffset + params.ReadSize - 1) / layout.blockSize // Store the current offset, so we can set it back once verification // finishes. - origOffset, err := data.Seek(0, io.SeekCurrent) + origOffset, err := params.File.Seek(0, io.SeekCurrent) if err != nil { - return 0, fmt.Errorf("Find current data offset failed: %v", err) + return 0, fmt.Errorf("find current data offset failed: %w", err) } - defer data.Seek(origOffset, io.SeekStart) + defer params.File.Seek(origOffset, io.SeekStart) // Move to the first block that contains target data. - if _, err := data.Seek(firstDataBlock*layout.blockSize, io.SeekStart); err != nil { - return 0, fmt.Errorf("Seek to datablock start failed: %v", err) + if _, err := params.File.Seek(firstDataBlock*layout.blockSize, io.SeekStart); err != nil { + return 0, fmt.Errorf("seek to datablock start failed: %w", err) } buf := make([]byte, layout.blockSize) @@ -255,7 +376,7 @@ func Verify(w io.Writer, data, tree io.ReadSeeker, dataSize int64, readOffset in for i := firstDataBlock; i <= lastDataBlock; i++ { // Read a block that includes all or part of target range in // input data. - bytesRead, err := data.Read(buf) + bytesRead, err := params.File.Read(buf) readErr = err // If at the end of input data and all previous blocks are // verified, return the verified input data and EOF. @@ -263,7 +384,7 @@ func Verify(w io.Writer, data, tree io.ReadSeeker, dataSize int64, readOffset in break } if readErr != nil && readErr != io.EOF { - return 0, fmt.Errorf("Read from data failed: %v", err) + return 0, fmt.Errorf("read from data failed: %w", err) } // If this is the end of file, zero the remaining bytes in buf, // otherwise they are still from the previous block. @@ -274,22 +395,29 @@ func Verify(w io.Writer, data, tree io.ReadSeeker, dataSize int64, readOffset in buf[j] = 0 } } - if err := verifyBlock(tree, layout, buf, i, expectedRoot); err != nil { + descriptor := VerityDescriptor{ + Name: params.Name, + Mode: params.Mode, + UID: params.UID, + GID: params.GID, + } + if err := verifyBlock(params.Tree, descriptor, layout, buf, i, params.ExpectedRoot); err != nil { return 0, err } + // startOff is the beginning of the read range within the // current data block. Note that for all blocks other than the // first, startOff should be 0. startOff := int64(0) if i == firstDataBlock { - startOff = readOffset % layout.blockSize + startOff = params.ReadOffset % layout.blockSize } // endOff is the end of the read range within the current data // block. Note that for all blocks other than the last, endOff // should be the block size. endOff := layout.blockSize if i == lastDataBlock { - endOff = (readOffset+readSize-1)%layout.blockSize + 1 + endOff = (params.ReadOffset+params.ReadSize-1)%layout.blockSize + 1 } // If the provided size exceeds the end of input data, we should // only copy the parts in buf that's part of input data. @@ -299,7 +427,7 @@ func Verify(w io.Writer, data, tree io.ReadSeeker, dataSize int64, readOffset in if endOff > int64(bytesRead) { endOff = int64(bytesRead) } - n, err := w.Write(buf[startOff:endOff]) + n, err := params.Out.Write(buf[startOff:endOff]) if err != nil { return total, err } @@ -313,9 +441,11 @@ func Verify(w io.Writer, data, tree io.ReadSeeker, dataSize int64, readOffset in // original data. The block is verified through each level of the tree. It // fails if the calculated hash from block is different from any level of // hashes stored in tree. And the final root hash is compared with -// expectedRoot. verifyBlock modifies the cursor for tree. Users needs to -// maintain the cursor if intended. -func verifyBlock(tree io.ReadSeeker, layout Layout, dataBlock []byte, blockIndex int64, expectedRoot []byte) error { +// expectedRoot. +// +// verifyBlock modifies the cursor for tree. Users needs to maintain the cursor +// if intended. +func verifyBlock(tree io.ReadSeeker, descriptor VerityDescriptor, layout Layout, dataBlock []byte, blockIndex int64, expectedRoot []byte) error { if len(dataBlock) != int(layout.blockSize) { return fmt.Errorf("incorrect block size") } @@ -352,21 +482,13 @@ func verifyBlock(tree io.ReadSeeker, layout Layout, dataBlock []byte, blockIndex } if !bytes.Equal(digest, expectedDigest) { - return fmt.Errorf("Verification failed") - } - - // If this is the root layer, no need to generate next level - // hash. - if level == layout.rootLevel() { - break + return fmt.Errorf("verification failed") } blockIndex = blockIndex / layout.hashesPerBlock() } - // Verification for the tree succeeded. Now compare the root hash in the - // tree with expectedRoot. - if !bytes.Equal(digest[:], expectedRoot) { - return fmt.Errorf("Verification failed") - } - return nil + // Verification for the tree succeeded. Now hash the descriptor with + // the root hash and compare it with expectedRoot. + descriptor.RootHash = digest + return verifyDescriptor(descriptor, expectedRoot) } diff --git a/pkg/merkletree/merkletree_test.go b/pkg/merkletree/merkletree_test.go index daaca759a..bb11ec844 100644 --- a/pkg/merkletree/merkletree_test.go +++ b/pkg/merkletree/merkletree_test.go @@ -84,6 +84,13 @@ func TestLayout(t *testing.T) { } } +const ( + defaultName = "merkle_test" + defaultMode = 0644 + defaultUID = 0 + defaultGID = 0 +) + // bytesReadWriter is used to read from/write to/seek in a byte array. Unlike // bytes.Buffer, it keeps the whole buffer during read so that it can be reused. type bytesReadWriter struct { @@ -138,19 +145,19 @@ func TestGenerate(t *testing.T) { }{ { data: bytes.Repeat([]byte{0}, usermem.PageSize), - expectedRoot: []byte{173, 127, 172, 178, 88, 111, 198, 233, 102, 192, 4, 215, 209, 209, 107, 2, 79, 88, 5, 255, 124, 180, 124, 122, 133, 218, 189, 139, 72, 137, 44, 167}, + expectedRoot: []byte{64, 253, 58, 72, 192, 131, 82, 184, 193, 33, 108, 142, 43, 46, 179, 134, 244, 21, 29, 190, 14, 39, 66, 129, 6, 46, 200, 211, 30, 247, 191, 252}, }, { data: bytes.Repeat([]byte{0}, 128*usermem.PageSize+1), - expectedRoot: []byte{62, 93, 40, 92, 161, 241, 30, 223, 202, 99, 39, 2, 132, 113, 240, 139, 117, 99, 79, 243, 54, 18, 100, 184, 141, 121, 238, 46, 149, 202, 203, 132}, + expectedRoot: []byte{182, 223, 218, 62, 65, 185, 160, 219, 93, 119, 186, 88, 205, 32, 122, 231, 173, 72, 78, 76, 65, 57, 177, 146, 159, 39, 44, 123, 230, 156, 97, 26}, }, { data: []byte{'a'}, - expectedRoot: []byte{52, 75, 204, 142, 172, 129, 37, 14, 145, 137, 103, 203, 11, 162, 209, 205, 30, 169, 213, 72, 20, 28, 243, 24, 242, 2, 92, 43, 169, 59, 110, 210}, + expectedRoot: []byte{28, 201, 8, 36, 150, 178, 111, 5, 193, 212, 129, 205, 206, 124, 211, 90, 224, 142, 81, 183, 72, 165, 243, 240, 242, 241, 76, 127, 101, 61, 63, 11}, }, { data: bytes.Repeat([]byte{'a'}, usermem.PageSize), - expectedRoot: []byte{201, 62, 238, 45, 13, 176, 47, 16, 172, 199, 70, 13, 149, 118, 225, 34, 220, 248, 205, 83, 196, 191, 141, 252, 174, 27, 62, 116, 235, 207, 255, 90}, + expectedRoot: []byte{106, 58, 160, 152, 41, 68, 38, 108, 245, 74, 177, 84, 64, 193, 19, 176, 249, 86, 27, 193, 85, 164, 99, 240, 79, 104, 148, 222, 76, 46, 191, 79}, }, } @@ -158,16 +165,25 @@ func TestGenerate(t *testing.T) { t.Run(fmt.Sprintf("%d:%v", len(tc.data), tc.data[0]), func(t *testing.T) { for _, dataAndTreeInSameFile := range []bool{false, true} { var tree bytesReadWriter - var root []byte - var err error + params := GenerateParams{ + Size: int64(len(tc.data)), + Name: defaultName, + Mode: defaultMode, + UID: defaultUID, + GID: defaultGID, + TreeReader: &tree, + TreeWriter: &tree, + DataAndTreeInSameFile: dataAndTreeInSameFile, + } if dataAndTreeInSameFile { tree.Write(tc.data) - root, err = Generate(&tree, int64(len(tc.data)), &tree, &tree, dataAndTreeInSameFile) + params.File = &tree } else { - root, err = Generate(&bytesReadWriter{ + params.File = &bytesReadWriter{ bytes: tc.data, - }, int64(len(tc.data)), &tree, &tree, dataAndTreeInSameFile) + } } + root, err := Generate(¶ms) if err != nil { t.Fatalf("Got err: %v, want nil", err) } @@ -194,6 +210,10 @@ func TestVerify(t *testing.T) { // modified byte falls in verification range, Verify should // fail, otherwise Verify should still succeed. modifyByte int64 + modifyName bool + modifyMode bool + modifyUID bool + modifyGID bool shouldSucceed bool }{ // Verify range start outside the data range should fail. @@ -222,12 +242,48 @@ func TestVerify(t *testing.T) { modifyByte: 0, shouldSucceed: false, }, - // Invalid verify range (0 size) should fail. + // 0 verify size should only verify metadata. + { + dataSize: usermem.PageSize, + verifyStart: 0, + verifySize: 0, + modifyByte: 0, + shouldSucceed: true, + }, + // Modified name should fail verification. + { + dataSize: usermem.PageSize, + verifyStart: 0, + verifySize: 0, + modifyByte: 0, + modifyName: true, + shouldSucceed: false, + }, + // Modified mode should fail verification. { dataSize: usermem.PageSize, verifyStart: 0, verifySize: 0, modifyByte: 0, + modifyMode: true, + shouldSucceed: false, + }, + // Modified UID should fail verification. + { + dataSize: usermem.PageSize, + verifyStart: 0, + verifySize: 0, + modifyByte: 0, + modifyUID: true, + shouldSucceed: false, + }, + // Modified GID should fail verification. + { + dataSize: usermem.PageSize, + verifyStart: 0, + verifySize: 0, + modifyByte: 0, + modifyGID: true, shouldSucceed: false, }, // The test cases below use a block-aligned verify range. @@ -316,16 +372,25 @@ func TestVerify(t *testing.T) { for _, dataAndTreeInSameFile := range []bool{false, true} { var tree bytesReadWriter - var root []byte - var err error + genParams := GenerateParams{ + Size: int64(len(data)), + Name: defaultName, + Mode: defaultMode, + UID: defaultUID, + GID: defaultGID, + TreeReader: &tree, + TreeWriter: &tree, + DataAndTreeInSameFile: dataAndTreeInSameFile, + } if dataAndTreeInSameFile { tree.Write(data) - root, err = Generate(&tree, int64(len(data)), &tree, &tree, dataAndTreeInSameFile) + genParams.File = &tree } else { - root, err = Generate(&bytesReadWriter{ + genParams.File = &bytesReadWriter{ bytes: data, - }, int64(tc.dataSize), &tree, &tree, false /* dataAndTreeInSameFile */) + } } + root, err := Generate(&genParams) if err != nil { t.Fatalf("Generate failed: %v", err) } @@ -333,8 +398,34 @@ func TestVerify(t *testing.T) { // Flip a bit in data and checks Verify results. var buf bytes.Buffer data[tc.modifyByte] ^= 1 + verifyParams := VerifyParams{ + Out: &buf, + File: bytes.NewReader(data), + Tree: &tree, + Size: tc.dataSize, + Name: defaultName, + Mode: defaultMode, + UID: defaultUID, + GID: defaultGID, + ReadOffset: tc.verifyStart, + ReadSize: tc.verifySize, + ExpectedRoot: root, + DataAndTreeInSameFile: dataAndTreeInSameFile, + } + if tc.modifyName { + verifyParams.Name = defaultName + "abc" + } + if tc.modifyMode { + verifyParams.Mode = defaultMode + 1 + } + if tc.modifyUID { + verifyParams.UID = defaultUID + 1 + } + if tc.modifyGID { + verifyParams.GID = defaultGID + 1 + } if tc.shouldSucceed { - n, err := Verify(&buf, bytes.NewReader(data), &tree, tc.dataSize, tc.verifyStart, tc.verifySize, root, dataAndTreeInSameFile) + n, err := Verify(&verifyParams) if err != nil && err != io.EOF { t.Errorf("Verification failed when expected to succeed: %v", err) } @@ -348,7 +439,7 @@ func TestVerify(t *testing.T) { t.Errorf("Incorrect output buf from Verify") } } else { - if _, err := Verify(&buf, bytes.NewReader(data), &tree, tc.dataSize, tc.verifyStart, tc.verifySize, root, dataAndTreeInSameFile); err == nil { + if _, err := Verify(&verifyParams); err == nil { t.Errorf("Verification succeeded when expected to fail") } } @@ -368,16 +459,26 @@ func TestVerifyRandom(t *testing.T) { for _, dataAndTreeInSameFile := range []bool{false, true} { var tree bytesReadWriter - var root []byte - var err error + genParams := GenerateParams{ + Size: int64(len(data)), + Name: defaultName, + Mode: defaultMode, + UID: defaultUID, + GID: defaultGID, + TreeReader: &tree, + TreeWriter: &tree, + DataAndTreeInSameFile: dataAndTreeInSameFile, + } + if dataAndTreeInSameFile { tree.Write(data) - root, err = Generate(&tree, int64(len(data)), &tree, &tree, dataAndTreeInSameFile) + genParams.File = &tree } else { - root, err = Generate(&bytesReadWriter{ + genParams.File = &bytesReadWriter{ bytes: data, - }, int64(dataSize), &tree, &tree, dataAndTreeInSameFile) + } } + root, err := Generate(&genParams) if err != nil { t.Fatalf("Generate failed: %v", err) } @@ -387,9 +488,24 @@ func TestVerifyRandom(t *testing.T) { size := rand.Int63n(dataSize) + 1 var buf bytes.Buffer + verifyParams := VerifyParams{ + Out: &buf, + File: bytes.NewReader(data), + Tree: &tree, + Size: dataSize, + Name: defaultName, + Mode: defaultMode, + UID: defaultUID, + GID: defaultGID, + ReadOffset: start, + ReadSize: size, + ExpectedRoot: root, + DataAndTreeInSameFile: dataAndTreeInSameFile, + } + // Checks that the random portion of data from the original data is // verified successfully. - n, err := Verify(&buf, bytes.NewReader(data), &tree, dataSize, start, size, root, dataAndTreeInSameFile) + n, err := Verify(&verifyParams) if err != nil && err != io.EOF { t.Errorf("Verification failed for correct data: %v", err) } @@ -406,13 +522,22 @@ func TestVerifyRandom(t *testing.T) { t.Errorf("Incorrect output buf from Verify") } + // Verify that modified metadata should fail verification. buf.Reset() + verifyParams.Name = defaultName + "abc" + if _, err := Verify(&verifyParams); err == nil { + t.Error("Verify succeeded for modified metadata, expect failure") + } + // Flip a random bit in randPortion, and check that verification fails. + buf.Reset() randBytePos := rand.Int63n(size) data[start+randBytePos] ^= 1 + verifyParams.File = bytes.NewReader(data) + verifyParams.Name = defaultName - if _, err := Verify(&buf, bytes.NewReader(data), &tree, dataSize, start, size, root, dataAndTreeInSameFile); err == nil { - t.Errorf("Verification succeeded for modified data") + if _, err := Verify(&verifyParams); err == nil { + t.Error("Verification succeeded for modified data, expect failure") } } } |