acme.sh VS private-network-access

A self-signed certificate was generated and used by Proxmox which will always generate a warning on the browser. I did not like seeing this when trying to work on my home lab. So, I started looking for ways to put a valid SSL certificate in Proxmox. During my research, I found that Proxmox could be made to integrate with acme.sh; a free SSL certificate generator powered by ACME(Let's Encrypt).

Next, we will install acme.sh, a command-line tool for managing SSL/TLS certificates. I prefer acme.sh over certbot, as it does not depend on the OS version. For more details about acme.sh, check its GitHub repo here.

A very relevant question. Acme.sh, a similar shell script ACME client, had a remote code execution problem last year.

https://github.com/acmesh-official/acme.sh/issues/4668

As a result, any certificates issued (or renewed) after Feb 8th will not work on older Android devices (< 7.1.1), unless the ACME client has been configure to request an alternate certificate chain. The "alternate chain" workaround will also stop working on June 6th.

I need to support these older Android devices so I am looking for alternatives. I have seen ZeroSSL mentioned a few times; it is also the default CA for acme.sh (the ACME client I am using nowadays) [2]. They have a number of paid plans but ACME certificates are free [3].

I'll be testing this over the next few days, but I would also like to ask if people here have experience with ZeroSSL (good or bad :-). Any feedback would be helpful.

[1]: https://letsencrypt.org/2023/07/10/cross-sign-expiration.html

[2]: https://github.com/acmesh-official/acme.sh

[3]: https://zerossl.com/documentation/acme/

Huh, the environment variable thing was specifically aimed at acme.sh which rather arbitrarily changed the config value from ACMEDNS_UPDATE_URL to ACMEDNS_BASE_URL, never acknowledged this in a changelog and then silently failed after an automatic upgrade as recommended by the default install:

https://github.com/acmesh-official/acme.sh/commit/2ce145f359...

It's also cleared out my .account.conf files when run on the suggested cron.

I've started using updown which also monitors my TLS certs simply because I no longer trust the process to work as documented.

It depends on your provider though. I can tell from experience that with OVH and their API, it's been easy to set up the automatic renewal via DNS verification. Apparently, the official client has support for the DNS API of 159 providers: https://github.com/acmesh-official/acme.sh/wiki/dnsapi

For the few people here that happen to run a self-hosted email server with acme.sh for TLS key/cert generation and Cloudflare for DNS management, I have made a tool that i personally use to get a perfect 100% score on Internet.nl's email test.

All of this is to say it's a decent amount of work to save the hassle of deploying certbot or acme.sh on the remote machines, pick your poison.

Here is a really solid guide for setting up the ACME DNS challenge with pretty much any DNS provider

People wonder why I like using the shell-based ACME client like dehydrated (or acme.sh):

* https://packages.debian.org/search?keywords=dehydrated

* https://github.com/acmesh-official/acme.sh

Versus the official client certbot:

* https://packages.debian.org/search?keywords=python3-certbot

A kludgy as very long shell scripts are (thought to be), I have a better chance of being able to go through all the code and understand it than a dozen(+) Python libraries.

// man getsockname // Get client address int sockn = getsockname(request, (struct sockaddr*)&client_addr, (socklen_t*)&client_addrlen); if (sockn < 0) { JS_ThrowInternalError(ctx, "server error (getsockname): %s", strerror(errno)); continue; } char buffer[BUFFER_SIZE]; // man 2 read // Read from the socket int readable = read(request, buffer, BUFFER_SIZE); if (readable < 0) { JS_ThrowInternalError(ctx, "server error (read): %s", strerror(errno)); continue; } // man sscanf // man inet_ntoa // man ntohs // Read the request char method[128], uri[128], version[128]; sscanf(buffer, "%s %s %s", method, uri, version); // ... if (!strcmp(method, "QUERY") || !strcmp(method, "POST")) { // https://developer.chrome.com/blog/private-network-access-preflight/ // https://wicg.github.io/local-network-access/ char response[] = "HTTP/1.1 200 OK\r\n" "Server: webserver-c\r\n" "Cross-Origin-Opener-Policy: unsafe-none\r\n" "Connection: keepalive\r\n" "Cross-Origin-Embedder-Policy: unsafe-none\r\n" "Access-Control-Allow-Headers: cache-control\r\n" "Access-Control-Allow-Methods: OPTIONS,POST,GET,HEAD,QUERY\r\n" "Access-Control-Allow-Credentials: true\r\n" "Cache-Control: no-store\r\n" "Access-Control-Allow-Origin: *\r\n" "Content-type: text/plain\r\n" "Access-Control-Allow-Private-Network: true\r\n\r\n"; char* body_signal = strstr(buffer, "\r\n\r\n"); char* body = body_signal + 4; status(ctx, argv[1], body); uint8_t writable[65536]; int writer = write(request, response, strlen(response)); if (writer < 0) { return JS_ThrowInternalError(ctx, "server error (write): %s", strerror(errno)); } // man popen FILE* pipe = popen(body, "r"); if (pipe == NULL) { return JS_ThrowInternalError(ctx, "server error (popen): %s", strerror(errno)); } for (;;) { // man fread size_t count = fread(writable, 1, sizeof(writable), pipe); int stream = write(request, writable, count); if (stream < 0 || count == 0) { // man pclose pclose(pipe); status(ctx, argv[1], "aborted"); break; } } close(request); for (int i = 0; i < sizeof(buffer) - 1; i++) { buffer[i] = '\0'; }

Because browsers make a distinction between private networks and public networks.

Has anyone done any testing/mitigation in regards to Chrome v107 and Cisco UC/CCE applications in regards to the Private Network Access changes?

See also: https://wicg.github.io/private-network-access/

Browser are also working to add IE6's zones* feature back in: https://wicg.github.io/private-network-access/

* I'm not actually sure if that did anything regarding cross-zone requests or if it was just "yeah, ActiveX is totally super-fine with me, as long as it comes from a trusted zone".

Yes. It's in the doc: https://wicg.github.io/private-network-access/

Of course one obvious workaround is to misconfigure your router to allocate from a non-private but unused/reserved address space. That way your internal network is also on the "outside".