From 8383de8a9db5551229e9005db92a84b83b7350fe Mon Sep 17 00:00:00 2001
From: Justin He <justin.he814@gmail.com>
Date: Fri, 1 Mar 2024 19:19:18 +0200
Subject: [PATCH] Update cloudflare-template.sh

Made several changes in the script to make it looks better.
The log messages and header name are adjusted to reflect IPv4 addressing.
---
 cloudflare-template.sh | 204 ++++++++++++++++++++++++-----------------
 1 file changed, 118 insertions(+), 86 deletions(-)

diff --git a/cloudflare-template.sh b/cloudflare-template.sh
index 32cbaa8..a8801a5 100644
--- a/cloudflare-template.sh
+++ b/cloudflare-template.sh
@@ -1,123 +1,155 @@
 #!/bin/bash
 ## change to "bin/sh" when necessary
 
-auth_email=""                                       # The email used to login 'https://dash.cloudflare.com'
-auth_method="token"                                 # Set to "global" for Global API Key or "token" for Scoped API Token
-auth_key=""                                         # Your API Token or Global API Key
-zone_identifier=""                                  # Can be found in the "Overview" tab of your domain
-record_name=""                                      # Which record you want to be synced
-ttl="3600"                                          # Set the DNS TTL (seconds)
-proxy="false"                                       # Set the proxy to true or false
-sitename=""                                         # Title of site "Example Site"
-slackchannel=""                                     # Slack Channel #example
-slackuri=""                                         # URI for Slack WebHook "https://hooks.slack.com/services/xxxxx"
-discorduri=""                                       # URI for Discord WebHook "https://discordapp.com/api/webhooks/xxxxx"
-
-
-###########################################
-## Check if we have a public IP
-###########################################
-ipv4_regex='([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])'
-ip=$(curl -s -4 https://cloudflare.com/cdn-cgi/trace | grep -E '^ip'); ret=$?
-if [[ ! $ret == 0 ]]; then # In the case that cloudflare failed to return an ip.
-    # Attempt to get the ip from other websites.
-    ip=$(curl -s https://api.ipify.org || curl -s https://ipv4.icanhazip.com)
-else
-    # Extract just the ip from the ip line from cloudflare.
-    ip=$(echo $ip | sed -E "s/^ip=($ipv4_regex)$/\1/")
+##############  CLOUDFLARE CREDENTIALS  ##############
+# @auth_email           - The email used to login 'https://dash.cloudflare.com'
+# @auth_method          - Set to "global" for Global API Key or "token" for Scoped API Token
+# @auth_key             - Your API Token or Global API Key
+# @zone_identifier      - Can be found in the "Overview" tab of your domain
+# -------------------------------------------------- #
+auth_email=""
+auth_method="token"
+auth_key=""
+zone_identifier=""
+
+#############  DNS RECORD CONFIGURATION  #############
+# @record_name          - Which record you want to be synced
+# @ttl                  - DNS TTL (seconds), can be set between (30 if enterprise) 60 and 86400 seconds, or 1 for Automatic
+# @proxy                - Set the proxy to true or false
+# -------------------------------------------------- #
+record_name=""
+ttl="3600"
+proxy="false"
+
+###############  SCRIPT CONFIGURATION  ###############
+# @log_header_name      - Header name used for logs
+# -------------------------------------------------- #
+log_header_name="DDNS Updater"
+
+#############  WEBHOOKS CONFIGURATION  ###############
+# @sitename             - Title of site "Example Site"
+# @slackchannel         - Slack Channel #example
+# @slackuri             - URI for Slack WebHook "https://hooks.slack.com/services/xxxxx"
+# @discorduri           - URI for Discord WebHook "https://discordapp.com/api/webhooks/xxxxx"
+# -------------------------------------------------- #
+sitename=""
+slackchannel=""
+slackuri=""
+discorduri=""
+
+################################################
+## Make sure we have a valid IPv4 connection
+################################################
+if ! { curl -4 -s --head --fail https://ipv4.google.com >/dev/null; }; then
+    logger -s "$log_header_name: Unable to establish a valid IPv4 connection to a known host."
+    exit 1
 fi
 
-# Use regex to check for proper IPv4 format.
+################################################
+## Finding our IPv4 address
+################################################
+ip=$(curl -s -4 https://api.ipify.org || curl -s -4 https://ipv4.icanhazip.com)
+
+# Check point: Make sure the collected IPv4 address is valid
+ipv4_regex='([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])'
 if [[ ! $ip =~ ^$ipv4_regex$ ]]; then
-    logger -s "DDNS Updater: Failed to find a valid IP."
-    exit 2
+    logger -s "$log_header_name: Failed to find a valid IPv4 address."
+    exit 1
 fi
 
-###########################################
+################################################
 ## Check and set the proper auth header
-###########################################
+################################################
 if [[ "${auth_method}" == "global" ]]; then
-  auth_header="X-Auth-Key:"
+    auth_header="X-Auth-Key:"
 else
-  auth_header="Authorization: Bearer"
+    auth_header="Authorization: Bearer"
 fi
 
-###########################################
+################################################
 ## Seek for the A record
-###########################################
-
-logger "DDNS Updater: Check Initiated"
+################################################
+logger "$log_header_name: Check Initiated"
 record=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records?type=A&name=$record_name" \
-                      -H "X-Auth-Email: $auth_email" \
-                      -H "$auth_header $auth_key" \
-                      -H "Content-Type: application/json")
+    -H "X-Auth-Email: $auth_email" \
+    -H "$auth_header $auth_key" \
+    -H "Content-Type: application/json")
 
-###########################################
+################################################
 ## Check if the domain has an A record
-###########################################
+################################################
 if [[ $record == *"\"count\":0"* ]]; then
-  logger -s "DDNS Updater: Record does not exist, perhaps create one first? (${ip} for ${record_name})"
-  exit 1
+    logger -s "$log_header_name: Record does not exist, perhaps create one first? (${ip} for ${record_name})"
+    exit 1
 fi
 
-###########################################
+################################################
 ## Get existing IP
-###########################################
+################################################
 old_ip=$(echo "$record" | sed -E 's/.*"content":"(([0-9]{1,3}\.){3}[0-9]{1,3})".*/\1/')
+
+# Make sure the extracted IPv4 address is valid
+if [[ ! $old_ip =~ ^$ipv4_regex$ ]]; then
+    logger -s "$log_header_name: Unable to extract existing IPv4 address from DNS record."
+    exit 1
+fi
+
 # Compare if they're the same
 if [[ $ip == $old_ip ]]; then
-  logger "DDNS Updater: IP ($ip) for ${record_name} has not changed."
-  exit 0
+    logger "$log_header_name: IP ($ip) for ${record_name} has not changed."
+    exit 0
 fi
 
-###########################################
+################################################
 ## Set the record identifier from result
-###########################################
+################################################
 record_identifier=$(echo "$record" | sed -E 's/.*"id":"([A-Za-z0-9_]+)".*/\1/')
 
-###########################################
+################################################
 ## Change the IP@Cloudflare using the API
-###########################################
+################################################
 update=$(curl -s -X PATCH "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records/$record_identifier" \
-                     -H "X-Auth-Email: $auth_email" \
-                     -H "$auth_header $auth_key" \
-                     -H "Content-Type: application/json" \
-                     --data "{\"type\":\"A\",\"name\":\"$record_name\",\"content\":\"$ip\",\"ttl\":\"$ttl\",\"proxied\":${proxy}}")
+    -H "X-Auth-Email: $auth_email" \
+    -H "$auth_header $auth_key" \
+    -H "Content-Type: application/json" \
+    --data "{\"content\":\"$ip\",\"ttl\":\"$ttl\",\"proxied\":$proxy}")
 
-###########################################
+################################################
 ## Report the status
-###########################################
+################################################
 case "$update" in
 *"\"success\":false"*)
-  echo -e "DDNS Updater: $ip $record_name DDNS failed for $record_identifier ($ip). DUMPING RESULTS:\n$update" | logger -s 
-  if [[ $slackuri != "" ]]; then
-    curl -L -X POST $slackuri \
-    --data-raw '{
-      "channel": "'$slackchannel'",
-      "text" : "'"$sitename"' DDNS Update Failed: '$record_name': '$record_identifier' ('$ip')."
-    }'
-  fi
-  if [[ $discorduri != "" ]]; then
-    curl -i -H "Accept: application/json" -H "Content-Type:application/json" -X POST \
-    --data-raw '{
-      "content" : "'"$sitename"' DDNS Update Failed: '$record_name': '$record_identifier' ('$ip')."
-    }' $discorduri
-  fi
-  exit 1;;
+    echo -e "$log_header_name: $ip $record_name DDNS failed for $record_identifier ($ip). DUMPING RESULTS:\n$update" | logger -s
+    if [[ $slackuri != "" ]]; then
+        curl -L -X POST $slackuri \
+            --data-raw "{
+                \"channel\": \"$slackchannel\",
+                \"text\": \"$sitename DDNS Update Failed: $record_name: $record_identifier ($ip).\"
+            }"
+    fi
+    if [[ $discorduri != "" ]]; then
+        curl -i -H "Accept: application/json" -H "Content-Type:application/json" -X POST \
+            --data-raw "{
+                \"content\": \"$sitename DDNS Update Failed: $record_name: $record_identifier ($ip).\"
+            }" $discorduri
+    fi
+    exit 1
+    ;;
 *)
-  logger "DDNS Updater: $ip $record_name DDNS updated."
-  if [[ $slackuri != "" ]]; then
-    curl -L -X POST $slackuri \
-    --data-raw '{
-      "channel": "'$slackchannel'",
-      "text" : "'"$sitename"' Updated: '$record_name''"'"'s'""' new IP Address is '$ip'"
-    }'
-  fi
-  if [[ $discorduri != "" ]]; then
-    curl -i -H "Accept: application/json" -H "Content-Type:application/json" -X POST \
-    --data-raw '{
-      "content" : "'"$sitename"' Updated: '$record_name''"'"'s'""' new IP Address is '$ip'"
-    }' $discorduri
-  fi
-  exit 0;;
+    logger "$log_header_name: $ip $record_name DDNS updated."
+    if [[ $slackuri != "" ]]; then
+        curl -L -X POST $slackuri \
+            --data-raw "{
+                \"channel\": \"$slackchannel\",
+                \"text\": \"$sitename Updated: $record_name's new IPv4 Address is $ip\"
+            }"
+    fi
+    if [[ $discorduri != "" ]]; then
+        curl -i -H "Accept: application/json" -H "Content-Type:application/json" -X POST \
+            --data-raw "{
+                \"content\": \"$sitename Updated: $record_name's new IPv4 Address is $ip\"
+            }" $discorduri
+    fi
+    exit 0
+    ;;
 esac