The Quiet Security Decision: Creating a Wallet Directory Across Three Nodes

The Message

[assistant] [bash] ssh 10.1.232.83 "sudo mkdir -p /home/fgw/.ribswallet && sudo chown fgw:fgw /home/fgw/.ribswallet && sudo chmod 700 /home/fgw/.ribswallet"
[bash] ssh 10.1.232.84 "sudo mkdir -p /home/fgw/.ribswallet && sudo chown fgw:fgw /home/fgw/.ribswallet && sudo chmod 700 /home/fgw/.ribswallet"

Two commands, executed against two remote machines. On the surface, this is a mundane infrastructure operation: create a directory, set ownership, set permissions. But within the larger narrative of deploying a distributed Filecoin Gateway (FGW) storage cluster across three physical nodes, this message represents a critical inflection point where security posture was explicitly hardened before any secrets touched disk.

The Moment Before

To understand why this message exists, we must understand what immediately preceded it. The assistant had been building out a QA test cluster for a horizontally scalable S3-compatible storage system built on Filecoin and YugabyteDB. The architecture involved three physical machines: a head node (10.1.232.82) running YugabyteDB, and two storage nodes (kuri1 at 10.1.232.83 and kuri2 at 10.1.232.84) running the Kuri storage daemon.

In message 1979, the user provided critical credentials: the wallet directory ~/.ribswallet containing Filecoin identity keys, and the CIDgravity API token stored in ~/.ribswallet/cidg.token. The assistant examined these files in message 1980, confirming the presence of two key files with restrictive permissions (-rw-------, mode 600) and the API token itself.

Then, in message 1982, the assistant set up the basic infrastructure on both nodes: creating the fgw system user, establishing data directories under /data/fgw/, and creating the binary and log directories. This was the standard provisioning step — getting the skeleton in place.

But message 1983 is different. It is not about data directories or binaries. It is about the wallet directory specifically. The assistant deliberately created /home/fgw/.ribswallet on both remote nodes before copying any secrets into it. This ordering is significant: the secure container was prepared before its contents ever crossed the network.

The Reasoning: Why This Message Was Written

The assistant's reasoning can be reconstructed from the surrounding context. The wallet directory on the head node (~/.ribswallet/) already existed with restrictive permissions (drwx------, owned by theuser). The CIDgravity token file was readable only by its owner (-rw-r--r-- for the token, which the user later flagged as a concern about plaintext secrets). The assistant had just received a clear signal from the user that secrets must not be stored in plaintext or in version-controlled locations.

The decision to create /home/fgw/.ribswallet with chmod 700 on each remote node before copying any files reflects a security-first mindset. The assistant was establishing a vault — a directory that only the fgw user could access — and ensuring that the vault existed and was properly locked before any keys were placed inside. This is analogous to building a safe, testing the lock, and only then placing valuables inside.

The choice of 700 (owner-only read/write/execute) rather than 750 (owner + group read) or 755 (world-readable) is deliberate. The wallet directory contains cryptographic material that authenticates the node's identity on the Filecoin network. If compromised, an attacker could impersonate the storage provider, redirect deals, or access deal-making infrastructure. The 700 permission enforces the principle of least privilege: only the fgw user — the dedicated service account — can access these secrets. Not other users on the system, not backup processes, not monitoring agents.

The Technical Decision Chain

The assistant made several interconnected decisions in this message:

1. Per-node isolation. Each storage node received its own .ribswallet directory, even though both nodes would ultimately receive copies of the same wallet keys. This was not a shared NFS mount or a symlink to a common location. Each node had its own independent vault, ensuring that a compromise of one node would not automatically expose the other.

2. Home directory placement. The wallet directory was placed under /home/fgw/.ribswallet rather than under /data/fgw/ (the data directory) or /opt/fgw/ (the binary directory). This follows Unix convention: user-specific configuration and secrets belong in the user's home directory. It also provides a clear separation between data (which might need different backup policies) and secrets (which need strict access control).

3. Pre-creation before copy. The directory was created and secured before any files were transferred. In message 1984, immediately after, the assistant attempted to copy wallet files into these directories. Had the directory not existed or had it been world-readable, the copied secrets would have been exposed. By preparing the secure container first, the assistant eliminated the window where secrets might land in an insecure location.

4. Sudo elevation. The commands run via sudo, which is necessary because creating directories in /home/fgw/ and changing ownership requires root privileges. However, the assistant was careful to set ownership to fgw:fgw immediately, so that the directory would be owned by the service account, not by root. This prevents the service from needing to run as root to access its own secrets.

Assumptions Made

The assistant made several assumptions in crafting this message:

That the fgw user already existed on both nodes. This assumption was validated by the immediately preceding message (1982), which created the user with sudo useradd -m -s /bin/bash fgw. The assistant was working sequentially, and the user creation had already completed.

That the home directory path would be /home/fgw/. This is the default home directory for a user created with useradd -m on Ubuntu/Debian systems. The assistant assumed the default, which was correct for these nodes.

That sudo was available and configured. The assistant had been using sudo throughout the session without issues, so this was a safe assumption.

That both nodes were symmetric. The same command was issued to both 10.1.232.83 and 10.1.232.84, assuming identical OS configurations. This was a reasonable assumption for a QA cluster where both nodes were provisioned identically.

That the wallet directory did not already exist. The mkdir -p flag ensures no error if the directory exists, but the assistant was creating it fresh. If the directory had existed with different permissions, the chmod 700 would override them — which could be either a correction or a destructive change depending on prior state.

What Went Wrong (and What Almost Went Wrong)

The immediate aftermath reveals a subtle bug. In message 1984, the assistant copied wallet files to both nodes and then ran:

sudo chown fgw:fgw /home/fgw/.ribswallet/*

This failed with "No such file or directory" because the shell glob * expanded before the sudo ran, and the files had just been moved but the wildcard was evaluated in the non-sudo context where the directory was inaccessible (permission 700, owned by fgw, but the files were still owned by theuser). The assistant had to fix this in message 1987 by explicitly naming the files.

This is a classic Unix permissions gotcha: a directory with 700 permissions owned by user A is inaccessible to user B, even with sudo. The sudo elevates privileges for the command, but the shell glob expansion happens in the user's context before sudo executes. The assistant's pre-creation of the directory with 700 permissions actually caused this error — the secure directory was so locked down that the wildcard couldn't see its contents.

This is not a mistake in the security design, but it reveals an interesting tension: security measures can create operational friction. The assistant correctly prioritized security (creating the locked directory first) but then encountered a workflow issue when trying to manipulate files inside it. The fix — explicitly naming files rather than using a wildcard — is a reasonable workaround, though a more robust approach might have been to set 700 permissions after copying the files, or to use sudo with a shell that expands the wildcard in the elevated context (sudo bash -c 'chown ...').

Input Knowledge Required

To understand this message, one needs:

Output Knowledge Created

This message produced:

The Broader Security Pattern

This message is part of a larger security pattern visible throughout the session. The assistant was repeatedly careful about secret management:

Conclusion

Message 1983 is easy to overlook. It is two lines of shell commands, barely worth a second glance in a session spanning hundreds of messages. But it represents a deliberate architectural decision: secrets in this cluster would be treated with the same rigor as production infrastructure, even though this was "just" a QA deployment. The assistant chose to build the vault before filling it, to lock the door before placing valuables inside. That choice, and the minor operational friction it created, tells us something important about how infrastructure should be built: security first, convenience second, and always with the understanding that the most critical decisions are often the quietest ones.