Decryption fails with null function or function signature mismatch

[manivasagant]

@utelle I am getting Exception: null function or function signature mismatch while reading the encrypted DB.

Database: Encrypted with chacha20 using better sqlite3 multiple ciphers and trying to read from sqlit3mc WASM
Platform: Mac OS 15.5.
Available VFSes: (8) ['multipleciphers-unix-none', 'opfs-encrypted', 'opfs', 'unix-none', 'memdb', 'unix-excl', 'unix-dotfile', 'unix']

I am writing encrypted bytes into default VFS and opening DB with oo1.DB and using pragma commands to set key. Not sure what I am missing. I am new to this, so would greatly appreciate any guidance or help.

`async function openEncryptedDatabase(encryptedDbBytes, hexKey) {
try {
const capi = sqlite3.capi;
const oo1 = sqlite3.oo1;

const dbName = "zeus.db";

capi.sqlite3_js_posix_create_file(dbName, encryptedDbBytes, encryptedDbBytes.length);
let db = new oo1.DB(dbName, 'r');

db.exec("PRAGMA cipher = 'chacha20';");
db.exec("PRAGMA page_size = 4096;");
db.exec(PRAGMA key = "x'${hexKey}'";);

db.exec("SELECT * FROM sqlite_master;");
}`

Note: I am using latest precompiled bundle of sqlite3.wasm /JavaScript APIs from https://github.com/utelle/SQLite3MultipleCiphers/releases/download/v2.2.3/sqlite3mc-2.2.3-sqlite-3.50.3-wasm.zip

[utelle]

I am getting Exception: null function or function signature mismatch while reading the encrypted DB.

The message null function or function signature mismatch is very generic and gives absolutely no clue what and where something failed. What I can say is that the message is not issued from any SQLite or SQLite3MC code .

Database: Encrypted with chacha20 using better sqlite3 multiple ciphers and trying to read from sqlit3mc WASM Platform: Mac OS 15.5. Available VFSes: (8) ['multipleciphers-unix-none', 'opfs-encrypted', 'opfs', 'unix-none', 'memdb', 'unix-excl', 'unix-dotfile', 'unix']

What irritates me is the VFS opfs-encrypted in the list of VFSes. Where does it come from?

Using the test tester1-worker from the samples coming with the SQLite3MC WASM distribution I get all mentioned VFSes except for opfs-encrypted.

I am writing encrypted bytes into default VFS and opening DB with oo1.DB and using pragma commands to set key. Not sure what I am missing. I am new to this, so would greatly appreciate any guidance or help.

Unfortunately, I have very limited experience with SQLite WASM. If you can adjust for example the sample demo-123-worker to exhibit the problem you experience, I will take a look.

Note: I am using latest precompiled bundle of sqlite3.wasm /JavaScript APIs from https://github.com/utelle/SQLite3MultipleCiphers/releases/download/v2.2.3/sqlite3mc-2.2.3-sqlite-3.50.3-wasm.zip

Well, I see the VFS multipleciphers-unix-none in the list of VFSes, so obviously you are using a version of SQLite3MC. You can use capi.sqlite3mc_version() to verify the version.

However, I'd really like to know where the VFS opfs-encrypted comes from. Is it part of your application? What does it do?

[manivasagant]

Thank you for looking into this.

You are right, "opfs-encrypted" is created by application code to verify OPFS works as part of initiation script and not cleaned up.. This will not be part of production code.

I will look into demo-123-worker example and get back if still face any error. Appreciate your help.

[utelle]

You are right, "opfs-encrypted" is created by application code to verify OPFS works as part of initiation script and not cleaned up.. This will not be part of production code.

Of course, you can have additional VFSes in your application, if they don't interfer with SQLite3 Multiple Ciphers.

BTW, you can open an encrypted OPFS database by simply using a call like the following:

const db = new oo.DB("/mydb2.sqlite3",'ct', 'multipleciphers-opfs');

The VFS multipleciphers-opfs will be created on the fly, if it wasn't instantiated earlier.

I will look into demo-123-worker example and get back if still face any error. Appreciate your help.

The message null function or function signature mismatch originates most likely somewhere from the JavaScript part of your application. Without further details (for example the call stack at the moment of the failure) it is really impossible to find out what is going wrong.