LibrePortal/scripts/network/ip/ip_find_available.sh
librelad 770492b7c7 Allocate IPs per missing service, not all-or-nothing
Not a flake. IP allocation lived in the else-branch of "did the database return
any rows for this app", so it ran only when the app held ZERO rows. An app with
even one row skipped the loop entirely, and a service without a row never got an
IP and never would. Its IP_TAG_<n> stayed unfilled, the literal IP_DATA_<n>
reached the compose, and docker refused the app with

  invalid IPv4 address: ParseAddr("IP_DATA_3")

which surfaced as "no container started (image pull failed?)". Nothing repaired
it: reinstalling re-ran the same skip, so the app stayed broken until someone
uninstalled it and wiped the rows.

Partial state is not exotic — an app that GAINS a service in a later version hits
this on its very next install, because the old services still hold rows. That is
the case worth worrying about; Stoat only got there by being installed and
uninstalled repeatedly.

Reproduced deterministically by deleting one row from a healthy 16-service Stoat:
the install reported "No IP allocated for service: stoat-rabbit" as a NOTICE,
then "Success: Updated 15 IP tag system", then failed at compose. After the fix
the same broken state self-heals — "Allocated IP: stoat/stoat-rabbit" — with no
uninstall.

Three more bugs in the same path, all found while tracing it:

- ipFindAvailable tested pool membership with a substring match against the
  newline-joined list of allocated IPs, so .4 read as taken whenever .46 or .147
  existed. Demonstrated: with 3 addresses allocated it excluded 5. Harmless at
  low occupancy, but it silently shrinks the pool as it fills and would report
  exhaustion early. Now an exact whole-line match.

- ipFindAvailable set available_ip="" on an exhausted pool and carried on to
  index the empty array, where RANDOM % 0 is a division-by-zero that would bury
  the real message. ipAllocation did the same and still ran its INSERT, writing
  a row with an empty resource_value — which then satisfied "this service has an
  allocation" forever after, making the service unrepairable. Both now return.

- first_allocated_ip was only assigned inside the allocate branch, so on every
  reinstall (where rows already exist) it came out empty and the trusted-domains
  list shipped with a hole. Now taken from the mapping.

An unfilled tag is also an error rather than a notice now: the compose is
unshippable at that point, and reporting "Success: updated 15 IP tags" is how
this reached the user as a confusing pull failure several steps later. The
install backstop no longer guesses "(image pull failed?)" either — that guess
was written for one cause and misdirects for every other.

Verified: clean install allocates all 16 with no unfilled tags, a deliberately
broken row self-heals, and no duplicate IPs exist across any app.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-20 01:35:19 +01:00

60 lines
2.4 KiB
Bash
Executable File

#!/bin/bash
# Find available IP in pool with randomization
ipFindAvailable()
{
# Extract subnet base from CFG_NETWORK_SUBNET and use hardcoded sensible defaults
local subnet_base=$(echo "$CFG_NETWORK_SUBNET" | cut -d'/' -f1 | cut -d'.' -f1-3)
local start_last=2 # Hardcoded sensible default: .2
local end_last=254 # Hardcoded sensible default: .254
local existing_ips; existing_ips=$(runInstallOp sqlite3 "$docker_dir/$db_file" "SELECT resource_value FROM network_resources WHERE resource_type = 'ip' AND status = 'active';" 2>/dev/null)
if [[ $? -ne 0 ]]; then
isError "Database query failed while checking existing IPs"
available_ip=""
return 1
fi
# Exact whole-line matching. The membership test used to be a substring check
# against the newline-joined list, so .4 read as taken whenever .46 or .147
# existed — silently shrinking a /24 pool to the addresses that happen not to
# be a prefix of another. Wrapping both sides in newlines makes the match
# exact, which is also why the delimiters are added rather than compared
# element by element: it stays one string test.
existing_ips=$'\n'"${existing_ips}"$'\n'
# Create an array to store available IPs
local available_ip_pool=()
# Randomization: Shuffle the IP range
local ip_range=($(seq $start_last $end_last | shuf))
for i in "${ip_range[@]}"; do
# Skip reserved IPs (1=gateway, 254=broadcast)
if [[ $i -eq 1 || $i -eq 254 ]]; then
continue
fi
local test_ip="${subnet_base}.${i}"
# Check if IP is already allocated
if [[ "$existing_ips" != *$'\n'"$test_ip"$'\n'* ]]; then
available_ip_pool+=("$test_ip")
fi
done
# Check if we have any available IPs
if [[ ${#available_ip_pool[@]} -eq 0 ]]; then
isError "No available IP addresses in subnet $CFG_NETWORK_SUBNET and all expansion ranges exhausted"
available_ip=""
# Returning matters: the line below indexes the pool, and RANDOM % 0 is a
# division-by-zero that would bury the real "pool exhausted" message under
# a bash arithmetic error.
return 1
fi
# Randomly select an IP from the available pool
local random_index=$((RANDOM % ${#available_ip_pool[@]}))
available_ip="${available_ip_pool[$random_index]}"
}