From 674f71bba37a17c33f541d801c452104f98fe34f Mon Sep 17 00:00:00 2001
From: Valentin Lab <valentin.lab@kalysto.org>
Date: Mon, 5 Apr 2021 23:32:23 +0200
Subject: [PATCH] new: [rsync-backup-target] add rotated logs for ssh
 validation and each rsync session

Signed-off-by: Valentin Lab <valentin.lab@kalysto.org>
---
 rsync-backup-target/build/Dockerfile          |  7 +-
 .../build/src/usr/local/sbin/ssh-cmd-validate | 38 +++++++++--
 .../hooks/log_rotate-relation-joined          | 67 +++++++++++++++++++
 rsync-backup-target/metadata.yml              | 11 +++
 4 files changed, 115 insertions(+), 8 deletions(-)
 create mode 100755 rsync-backup-target/hooks/log_rotate-relation-joined

diff --git a/rsync-backup-target/build/Dockerfile b/rsync-backup-target/build/Dockerfile
index 554f34ba..5415bdc7 100644
--- a/rsync-backup-target/build/Dockerfile
+++ b/rsync-backup-target/build/Dockerfile
@@ -2,14 +2,15 @@ FROM alpine:3.9
 
 MAINTAINER Valentin Lab <valentin.lab@kalysto.org>
 
-RUN apk add rsync sudo bash openssh-server
+## coreutils is for ``date`` support of ``--rfc-3339=seconds`` argument.
+RUN apk add rsync sudo bash openssh-server coreutils
 RUN ssh-keygen -A
 
 ## New user/group rsync/rsync with home dir in /var/lib/rsync
-RUN mkdir -p /var/lib/rsync && \
+RUN mkdir -p /var/lib/rsync /var/log/rsync && \
     addgroup -S rsync && \
     adduser -S rsync -h /var/lib/rsync -G rsync && \
-    chown rsync:rsync /var/lib/rsync
+    chown rsync:rsync /var/lib/rsync /var/log/rsync
 
 ## Without this, account is concidered locked by SSH
 RUN sed -ri 's/^rsync:!:/rsync:*NP*:/g' /etc/shadow
diff --git a/rsync-backup-target/build/src/usr/local/sbin/ssh-cmd-validate b/rsync-backup-target/build/src/usr/local/sbin/ssh-cmd-validate
index e1940b21..415f8b56 100755
--- a/rsync-backup-target/build/src/usr/local/sbin/ssh-cmd-validate
+++ b/rsync-backup-target/build/src/usr/local/sbin/ssh-cmd-validate
@@ -5,14 +5,32 @@
 
 exname=$(basename "$0")
 
+mkdir -p /var/log/rsync
+
+LOG="/var/log/rsync/$exname.log"
+
+
+ssh_connection=(${SSH_CONNECTION})
+SSH_SOURCE_IP="${ssh_connection[0]}:${ssh_connection[1]}"
+
+log() {
+    printf "%s [%s] %s - %s\n" \
+           "$(date --rfc-3339=seconds)" "$$" "$SSH_SOURCE_IP" "$*" \
+           >> "$LOG"
+}
+
+log "NEW CONNECTION"
+
 if [ -z "$1" ] || ! [[ "$1" =~ ^[a-zA-Z0-9._-]+$ ]]; then
-    logger -t "$exname" "INVALID SETUP, ARG IS: '$1'"
+    log "INVALID SETUP, ARG IS: '$1'"
     echo "Your command has been rejected. Contact administrator."
     exit 1
 fi
 
+ident="$1"
+
 reject() {
-    logger -t "$exname" "REJECTED: $SSH_ORIGINAL_COMMAND"
+    log "REJECTED: $SSH_ORIGINAL_COMMAND"
     # echo "ORIG: $SSH_ORIGINAL_COMMAND" >&2
     echo "Your command has been rejected and reported to sys admin." >&2
     exit 1
@@ -20,15 +38,25 @@ reject() {
 
 
 if [[ "$SSH_ORIGINAL_COMMAND" =~ [\&\(\{\;\<\>\`\$\}] ]]; then
+    log "BAD CHARS DETECTED"
     # echo "Bad chars: $SSH_ORIGINAL_COMMAND" >&2
     reject
 fi
 
-if [[ "$SSH_ORIGINAL_COMMAND" =~ ^"rsync --server -"[vloHgDtpArRzCeiLsfx\.]+(" --"[a-z-]+|" --partial-dir .rsync-partial")*" . /var/mirror/$1"$ ]]; then
-	logger -t "$exname" "ACCEPTED: $SSH_ORIGINAL_COMMAND"
+if [[ "$SSH_ORIGINAL_COMMAND" =~ ^"rsync --server -"[vloHgDtpArRzCeiLsfx\.]+(" --"[a-z=%-]+|" --partial-dir .rsync-partial")*" . /var/mirror/$ident"$ ]]; then
+	log "ACCEPTED: $SSH_ORIGINAL_COMMAND"
+
+    ## Interpret \ to allow passing spaces (want to avoid possible issue with \n)
+    #read -a ssh_args <<< "${SSH_ORIGINAL_COMMAND}"
+    ssh_args=(${SSH_ORIGINAL_COMMAND})
+
     # echo "Would accept: $SSH_ORIGINAL_COMMAND" >&2
-	exec sudo $SSH_ORIGINAL_COMMAND
+	exec sudo "${ssh_args[@]::3}" \
+         "--log-file=/var/log/rsync/target_$1_rsync.log" \
+         "--log-file-format=%i %o %f %l %b" \
+         "${ssh_args[@]:3}"
 else
+    log "NO MATCH ACCEPTED COMMAND"
 	reject
 fi
 
diff --git a/rsync-backup-target/hooks/log_rotate-relation-joined b/rsync-backup-target/hooks/log_rotate-relation-joined
new file mode 100755
index 00000000..a7372e19
--- /dev/null
+++ b/rsync-backup-target/hooks/log_rotate-relation-joined
@@ -0,0 +1,67 @@
+#!/bin/bash
+
+## Should be executable N time in a row with same result.
+
+. lib/common
+
+set -e
+
+uid=$(docker_get_uid "$SERVICE_NAME" "rsync")
+
+
+LOGS=/var/log/rsync
+mkdir -p "$SERVICE_DATASTORE/$LOGS"
+touch "$SERVICE_DATASTORE/$LOGS/ssh-cmd-validate.log"
+chown -v "$uid" "$SERVICE_DATASTORE/$LOGS" "$SERVICE_DATASTORE/$LOGS/ssh-cmd-validate.log"
+
+rotated_count=$(relation-get rotated-count 2>/dev/null) || true
+rotated_count=${rotated_count:-52}
+
+
+## XXXvlab: a lot of this intelligence should be moved away into ``logrotate`` charm
+DST="$CONFIGSTORE/$TARGET_SERVICE_NAME/etc/logrotate.d/$SERVICE_NAME"
+file_put "$DST" <<EOF
+/var/log/docker/$SERVICE_NAME/ssh-cmd-validate.log
+{
+    weekly
+    missingok
+    dateext
+    dateyesterday
+    dateformat _%Y-%m-%d
+    extension .log
+    rotate $rotated_count
+    compress
+    delaycompress
+    notifempty
+    create 640 $uid
+    sharedscripts
+}
+
+/var/log/docker/$SERVICE_NAME/target_*_rsync.log
+{
+    weekly
+    missingok
+    dateext
+    dateyesterday
+    dateformat _%Y-%m-%d
+    extension .log
+    rotate $rotated_count
+    compress
+    delaycompress
+    notifempty
+    create 640
+    sharedscripts
+}
+EOF
+
+config-add "\
+services:
+  $MASTER_TARGET_SERVICE_NAME:
+    volumes:
+      - $DST:/etc/logrotate.d/docker-${SERVICE_NAME}:ro
+      - $SERVICE_DATASTORE$LOGS:/var/log/docker/$SERVICE_NAME:rw
+  $MASTER_BASE_SERVICE_NAME:
+    volumes:
+      - $SERVICE_DATASTORE$LOGS:$LOGS:rw
+
+"
diff --git a/rsync-backup-target/metadata.yml b/rsync-backup-target/metadata.yml
index 5cface63..a44906ee 100644
--- a/rsync-backup-target/metadata.yml
+++ b/rsync-backup-target/metadata.yml
@@ -1,3 +1,14 @@
 description: Backup Rsync over SSH Target
 data-resources:
   - /var/mirror
+  - /var/log/rsync
+
+uses:
+  log-rotate:
+    #constraint: required | recommended | optional
+    #auto: pair | summon | none ## default: pair
+    constraint: required
+    auto: summon
+    solves:
+      unmanaged-logs: "in docker logs"
+    #default-options: