asterisk: serve a static HTTP directory with busybox httpd

The Cisco phones on the Enterprise firmware fetch their directory
(directoryURL) over HTTP only. A separate root from the TFTP one: the
configuration files of the phones hold their SIP passwords.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UJKweojs6NK5svZwRgQjQH

cookbooks/asterisk/README.md

@@ -4,7 +4,7 @@
 
 [Asterisk](https://www.asterisk.org/) is an open source PBX. This cookbook runs it as a SIP server for
 phones on the local network, together with the TFTP server the phones fetch their configuration and
-firmware from.
+firmware from, and an HTTP server for their directory.
 
 This cookbook:
 
@@ -13,6 +13,7 @@ This cookbook:
 - Runs Asterisk directly as a dedicated, unprivileged UID/GID (no user namespace mapping), with
   PJSIP as its only channel driver.
 - Runs dnsmasq as a TFTP server only (no DNS, no DHCP), from the same image, as the same user.
+- Runs the httpd of busybox as a static HTTP server, from the same image, as the same user.
 - Loads an explicit list of Asterisk modules: what calls between SIP phones need, and nothing else.
 - Includes a timer to rebuild the container image daily.
 
@@ -34,11 +35,12 @@ interface.
 | `/etc/quadlets/asterisk/etc/extensions.conf` | Dialplan. Required. |
 | `/etc/quadlets/asterisk/etc/indications.conf` | Call progress tones of the country. Optional: without it, Asterisk logs a warning and uses no tones of its own; the phones play theirs. |
 | `/var/lib/virtiofs/data/asterisk/tftp/` | Configuration files and firmware images of the phones, as each vendor names them. Optional: the TFTP server also runs on an empty directory, so that files written later are served without a restart. |
+| `/var/lib/virtiofs/data/asterisk/http/` | Static files served over HTTP, such as the XML directory of the phones. Optional, like the TFTP root. Keep the configuration files of the phones out of it: they hold SIP passwords, and HTTP is easier to reach from another network than TFTP. |
 
 Asterisk does not start without `pjsip.conf` and `extensions.conf`. Examples of both are in
 `config/examples/etc/`.
 
-The TFTP root is on the virtiofs mount rather than under `/etc/quadlets`, so that the host can write
+The TFTP and HTTP roots are on the virtiofs mount rather than under `/etc/quadlets`, so that the host can write
 it: a firmware image weighs tens of megabytes, which an Ignition file cannot carry. The files must be
 readable by UID 10036.
 
@@ -53,14 +55,15 @@ missing.
 | 5060 | UDP | SIP |
 | 10000-10999 | UDP | RTP (set in `rtp.conf`) |
 | 69 | UDP | TFTP |
+| 80 | TCP | HTTP |
 
-Both containers use host networking.
+All three containers use host networking.
 
 ## UID and GID
 
 | UID | GID | Usage |
 |-----|-----|-------|
-| 10036 | 10000 | Asterisk and dnsmasq |
+| 10036 | 10000 | Asterisk, dnsmasq and httpd |
 
 ## Usage
 

cookbooks/asterisk/asterisk-http.container

@@ -0,0 +1,48 @@
+[Unit]
+Description=Asterisk - HTTP server for the directory of the phones
+Documentation=https://busybox.net/downloads/BusyBox.html
+
+Wants=asterisk-build.service
+After=network.target asterisk-build.service var-lib-virtiofs-data.mount
+Requires=var-lib-virtiofs-data.mount
+
+# Static files only, operator-provided on the precious-data mount, like the
+# TFTP root and for the same reasons. A separate directory from the TFTP root:
+# the configuration files of the phones hold their SIP passwords, and HTTP,
+# unlike TFTP, is easily reached from another network.
+
+# Start/stop this unit when the target is started/stopped
+PartOf=asterisk.target
+
+[Container]
+ContainerName=asterisk-http
+Image=localhost/asterisk:latest
+AutoUpdate=local
+
+User=10036
+Group=10000
+
+# HTTP listens on 80/tcp, a privileged port.
+AddCapability=CAP_NET_BIND_SERVICE
+
+# Host networking, as the two other containers: the phones reach the same
+# address for SIP, TFTP and HTTP.
+Network=host
+
+# busybox httpd: -f stays in the foreground, -v logs each request. It reads
+# /etc/httpd.conf of the image for the MIME type of XML files, and lists no
+# directory.
+Entrypoint=/usr/sbin/httpd
+Exec=-f -v -p 80 -h /var/lib/virtiofs/data/asterisk/http
+
+# Read-only: the phones fetch, they never upload.
+Volume=/var/lib/virtiofs/data/asterisk/http:/var/lib/virtiofs/data/asterisk/http:ro,z
+
+[Service]
+Restart=always
+RestartSec=10
+TimeoutStartSec=300
+TimeoutStopSec=30
+
+[Install]
+WantedBy=asterisk.target

cookbooks/asterisk/asterisk.target

@@ -2,8 +2,8 @@
 Description=Asterisk Service Target
 Documentation=man:systemd.target(5)
 Requires=asterisk.service asterisk-build.timer
-Wants=asterisk-tftp.service
-After=asterisk.service asterisk-tftp.service asterisk-build.timer
+Wants=asterisk-tftp.service asterisk-http.service
+After=asterisk.service asterisk-tftp.service asterisk-http.service asterisk-build.timer
 
 # Allow isolation - can stop/start this target independently
 AllowIsolate=yes

cookbooks/asterisk/config/container/Containerfile

@@ -2,8 +2,13 @@ FROM docker.io/library/alpine:3.24
 
 # Asterisk 22 (the LTS branch), PJSIP included: Alpine bundles pjproject in the
 # main package. dnsmasq serves the provisioning files of the phones over TFTP,
-# from the same image, so that a single build keeps both up to date.
-RUN apk add --no-cache asterisk dnsmasq
+# and the httpd of busybox-extras their directory over HTTP, from the same
+# image, so that a single build keeps all three up to date.
+RUN apk add --no-cache asterisk dnsmasq busybox-extras
+
+# busybox httpd sends no Content-Type for .xml files without this line, and
+# the XML services of the phones expect text/xml.
+RUN printf '.xml:text/xml; charset=utf-8\n' > /etc/httpd.conf
 
 # /etc/asterisk is empty: the sample files are in asterisk-sample-config, which
 # is not installed. The configuration is mounted read-only there at run time.

cookbooks/asterisk/tmpfiles.d/asterisk.conf

@@ -1,4 +1,5 @@
-# Provisioning files of the phones, served over TFTP. Operator-provided, on the
+# Provisioning files of the phones, served over TFTP, and their directory,
+# served over HTTP. Operator-provided, on the
 # precious-data mount so that the host can write them. The "$" marks it for
 # removal on `systemd-tmpfiles --purge` (i.e. `make uninstall`).
 #
@@ -13,3 +14,4 @@
 # not affected: its label is fixed by the mount.
 d$ /var/lib/virtiofs/data/asterisk 0750 10036 10000 -
 d$ /var/lib/virtiofs/data/asterisk/tftp 0750 10036 10000 -
+d$ /var/lib/virtiofs/data/asterisk/http 0750 10036 10000 -