kdump.etc, submit-report.sh: Enhance Steam ID/Account obtaining

Currently we hardcode the account-related VDF file path in kdump,
and expose it in "/etc/default/kdump" - this is unnecessary since
this path is not expected to change nor users to mess with it; thanks
Emil (@xexaxo) for this suggestion.

So, this patch improves things in some ways:

(a) Do not expose VDF path or Valve's server URL in user configurable
file - no reasons for users to mess with that.

(b) Generate "/home" mount point based on DEVNODE, also determine
the username based on "getent'ing" the passwd database. See CAVEAT
below.

(c) Move the VDF parsing to a separate function to clean up the
submit log path on submit-report.sh .

No functional change is expected after this commit.

CAVEAT: Notice that "getent passwd" is *VERY* slow, and if we follow
a generic approach of doing it for UID_MIN..UID_MAX, it takes quite
some time. So, instead we simplify and just query the user 1000; this
might be a bit incomplete, but it's still better than hardcoding a
username as it's done until now.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>

README.md

@@ -161,8 +161,7 @@
 #  => The API details: it works by a first POST request to Valve servers,
 #  which, when succeed, returns 3 main components in the response. We use
 #  these values to perform a PUT request with the ZIP compressed file, and
-#  finally a last POST request is necessary to finish the transaction. The
+#  finally a last POST request is necessary to finish the transaction.
-#  POST requests' URL is present in "/etc/default/kdump".
 #  Below, the specific format of such requests:
 #
 #  The first POST takes the following fields:

kdump.etc

@@ -43,9 +43,3 @@ USE_PSTORE_RAM=1
 #  Setting LOG_SUBMISSION to '0' will disable this behavior; but notice that
 #  even with the log submission disabled, the logs are saved locally.
 LOG_SUBMISSION=1
-
-#  Below some log submission settings, based on Steam config files and Valve
-#  URLs. These settings *should not* be changed, or else the log sending
-#  mechanism will be impaired.
-LOGINVDF="/home/doorstop/.local/share/Steam/config/loginusers.vdf"
-POST_URL="https://api.steampowered.com/ICrashReportService/ACTIONCrashUpload/v1"

submit-report.sh

@@ -22,6 +22,50 @@ save_locally_and_bail() {
 	exit 0
 }
 
+#  Next function is used to get Steam Account/ID from the VDF file for
+#  the current user; in case it fails, STEAM_ID and STEAM_ACCOUNT vars
+#  aren't updated.
+#  Arg1: devnode information to determine the /home mount point.
+
+get_steam_account_id() {
+	#  Step 1: get the /home mount point.
+	HOMEFLD="$(findmnt "$1" -fno TARGET)"
+
+	#  Step 2: determine the username; notice that
+	#  UID_MIN = 1000, UID_MAX = 60000 from "/etc/login.defs", but
+	#  getent takes long time to check all of them, so we restrict
+	#  to UID = 1000 only.
+	USERN="$(getent passwd 1000 | cut -f1 -d:)"
+
+	#  Let's determine the VDF file location using the above info.
+	LOGINVDF="${HOMEFLD}/${USERN}/.local/share/Steam/config/loginusers.vdf"
+	if [ ! -s "${LOGINVDF}" ]; then #  bail if no valid VDF is found.
+		return
+	fi
+
+	#  Step 3: Parse the VDF file to obtain Account/ID; the following AWK
+	#  command was borrowed from: https://unix.stackexchange.com/a/663959.
+	NUMREG=$(grep -c AccountName "${LOGINVDF}")
+	IDX=1
+	while [ ${IDX} -le "${NUMREG}" ]; do
+		MR=$(awk -v n=${IDX} -v RS='}' 'NR==n{gsub(/.*\{\n|\n$/,""); print}' "${LOGINVDF}" | grep "MostRecent" | cut -f4 -d\")
+		if [ "$MR" -ne 1 ]; then
+			IDX=$((IDX + 1))
+			continue
+		fi
+
+		STEAM_ACCOUNT=$(awk -v n=${IDX} -v RS='}' 'NR==n{gsub(/.*\{\n|\n$/,""); print}' "${LOGINVDF}" | grep "AccountName" | cut -f4 -d\")
+
+		#  Get also the Steam ID, used in the POST request to Valve servers; this
+		#  is a bit fragile, but there's no proper VDF parse tooling it seems...
+		LN=$(grep -n "AccountName.*${STEAM_ACCOUNT}\"" "${LOGINVDF}" | cut -f1 -d:)
+		LN=$((LN - 2))
+		STEAM_ID=$(sed -n "${LN}p" "${LOGINVDF}" | cut -f2 -d\")
+		break
+	done
+}
+
+
 #  We do some validation to be sure KDUMP_MNT pointed path is valid...
 #  That and having a valid /etc/default/kdump are essential conditions.
 if [ ! -s "/etc/default/kdump" ]; then
@@ -128,28 +172,7 @@ if [ ${LOGS_FOUND} -ne 0 ]; then
 
 	STEAM_ACCOUNT=0
 	STEAM_ID=0
-	if [ -s "${LOGINVDF}" ]; then
+	get_steam_account_id "${MOUNT_DEVNODE}"
-		#  The following awk command was borrowed from:
-		#  https://unix.stackexchange.com/a/663959
-		NUMREG=$(grep -c AccountName "${LOGINVDF}")
-		IDX=1
-		while [ ${IDX} -le "${NUMREG}" ]; do
-			MR=$(awk -v n=${IDX} -v RS='}' 'NR==n{gsub(/.*\{\n|\n$/,""); print}' "${LOGINVDF}" | grep "MostRecent" | cut -f4 -d\")
-			if [ "$MR" -ne 1 ]; then
-				IDX=$((IDX + 1))
-				continue
-			fi
-
-			STEAM_ACCOUNT=$(awk -v n=${IDX} -v RS='}' 'NR==n{gsub(/.*\{\n|\n$/,""); print}' "${LOGINVDF}" | grep "AccountName" | cut -f4 -d\")
-
-			#  Get also the Steam ID, used in the POST request to Valve servers; this
-			#  is a bit fragile, but there's no proper VDF parse tooling it seems...
-			LN=$(grep -n "AccountName.*${STEAM_ACCOUNT}\"" "${LOGINVDF}" | cut -f1 -d:)
-			LN=$((LN - 2))
-			STEAM_ID=$(sed -n "${LN}p" "${LOGINVDF}" | cut -f2 -d\")
-			break
-		done
-	fi
 
 	#  Here we collect some more info, like DMI data, os-release, etc;
 	#  TODO: Add Steam application / Proton / Games logs collection...
@@ -237,9 +260,11 @@ if [ ${LOGS_FOUND} -ne 0 ]; then
 		save_locally_and_bail "${NOT_SENT_FLD}" "${LOG_FNAME}"
 	fi
 
+	#  These URLs are hardcoded based on Valve's server information.
+	START_URL="https://api.steampowered.com/ICrashReportService/StartCrashUpload/v1"
+	FINISH_URL="https://api.steampowered.com/ICrashReportService/FinishCrashUpload/v1"
+
 	CURL_ERR="${KDUMP_MAIN_FOLDER}/.curl_err"
-	START_URL="$(echo "${POST_URL}" | sed 's/ACTION/Start/g')"
-	FINISH_URL="$(echo "${POST_URL}" | sed 's/ACTION/Finish/g')"
 	RESPONSE_FILE="${KDUMP_MAIN_FOLDER}/.curl_response"
 
 	if ! curl -X POST -d "${POST_REQ}" "${START_URL}" 1>"${RESPONSE_FILE}" 2>"${CURL_ERR}"; then