"cipher.final()" results in an abort

[zyscoder]

• Version: v14.15.1
• Platform: Linux 5.8.0-38-generic The binary and long term compatibility with node #43~20.04.1-Ubuntu SMP Tue Jan 12 16:39:47 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
• Subsystem: cipher.final()

What steps will reproduce the bug?

Setup a node instance,

» node

and run the following javascript code.

crypto.createCipher('aes-192-ccm',"",{authTagLength:10}).final()

Then the node instance occurs an abort.

How often does it reproduce? Is there a required condition?

This abort can always be triggered following the steps above.

What is the expected behavior?

If any error occurs, an exception or other similar error-reporting stuff should be thrown. There is no reason to abort the whole node process.

What do you see instead?

» node
Welcome to Node.js v14.15.1.
Type ".help" for more information.
> crypto.createCipher('aes-192-ccm',"",{authTagLength:10}).final()
node[145172]: ../src/node_crypto.cc:4120:bool node::crypto::CipherBase::Final(node::AllocatedBuffer*): Assertion `(1) == (EVP_CIPHER_CTX_ctrl(ctx_.get(), 0x10, auth_tag_len_, reinterpret_cast<unsigned char*>(auth_tag_)))' failed.
 1: 0xa03530 node::Abort() [node]
 2: 0xa035ae  [node]
 3: 0xb25c04 node::crypto::CipherBase::Final(node::AllocatedBuffer*) [node]
 4: 0xb2e764 node::crypto::CipherBase::Final(v8::FunctionCallbackInfo<v8::Value> const&) [node]
 5: 0xbe369b  [node]
 6: 0xbe4c46  [node]
 7: 0xbe52c6 v8::internal::Builtin_HandleApiCall(int, unsigned long*, v8::internal::Isolate*) [node]
 8: 0x13ff259  [node]
[1]    145172 abort (core dumped)  node                                                                                                                                                                                                               

Additional information

[zyscoder]

The crash traces look the same as #37922

[aduh95]

Duplicate of #38015. Although it's a different method, it's clearly the same underlying bug, or at least it must be related.

[aduh95]

Actually, final is not a method from the stream API as I incorrectly thought. It's probably a different bug.
I can reproduce on master.

The failed assertion is located here:

node/src/crypto/crypto_cipher.cc

Lines 847 to 849 in 640fe94

	CHECK_EQ(1, EVP_CIPHER_CTX_ctrl(ctx_.get(), EVP_CTRL_AEAD_GET_TAG,
	auth_tag_len_,
	reinterpret_cast<unsigned char*>(auth_tag_)));

[hergetr]

Hi, I just spent some hours to find a bug in my program. Before filing the bug report I searched for similar and came to this here.

Additional Information:

1. Same problem applies to crypto.createDecipheriv(...) which is not depricated.
2. In my case, the string was not empty. It was a valid hex-string, but ended with '\r' (carriage-return) (which was hard to find because node aborted without the nodejs-stackdump)
3. There is a workaround until fixed:
   • This crashes:
     decipher.write(encrypted, 'hex')
   • This works:
     const buf = Buffer.from(encrypted,'hex')
     decipher.write(buf)

Thank you very much !
Rainer

[Ayase-252]

@hergetr

Hi, thanks for report.

It sounds similar to #38015. Could you compare your error stack with that issue? If it is not same, please fill a new issue.

[hergetr]

@Ayase-252 :
Yes, same error, but I had a valid hex-string + '\r'.
It was valid for Buffer.from(..,'hex') which seems to have different behavor:

// a) Buffer's hex converter works:
Buffer.from('af34\r','hex') // works. It seems to trim the input.

// b) crypto's hex-converter fails:
const decipher = crypto.createDecipheriv(algorithm, key, iv)
decipher .write('af34\r','hex') // seems not to trim and aborts with Assertion `str->Length() % 2 == 0 ...

So, if you are there changing and afterwards testing the code anyway, maybe you could consider whether to add the trim() like Buffer.from() does? The nastyness of the whitespace was, that You cannot easily see it in the textfile where the '\r\n' comes from :-)

For completenes, here is my abort message.
node[5944]: ../src/string_bytes.cc:433:static v8::Maybe node::StringBytes::StorageSize(v8::Isolate*, v8::Localv8::Value, node::encoding): Assertion `str->Length() % 2 == 0 && "invalid hex string length"' failed.
1: 0xa04200 node::Abort() [node]
2: 0xa0427e [node]
3: 0xadd70a node::StringBytes::StorageSize(v8::Isolate*, v8::Localv8::Value, node::encoding) [node]
4: 0xb3a95e node::StringBytes::InlineDecoder::Decode(node::Environment*, v8::Localv8::String, node::encoding) [node]
5: 0xb3b7be void node::crypto::Decodenode::crypto::CipherBase(v8::FunctionCallbackInfov8::Value const&, void ()(node::crypto::CipherBase, v8::FunctionCallbackInfov8::Value const&, char const*, unsigned long)) [node]
6: 0xbe56eb [node]
7: 0xbe6c96 [node]
8: 0xbe7316 v8::internal::Builtin_HandleApiCall(int, unsigned long*, v8::internal::Isolate*) [node]
9: 0x14012f9 [node]
Aborted