PostgreSQL PAM authentication with Docker

I want to authenticate Linux host's users with the PostgreSQL database running in the docker container (If PG is installed natively, it works fine). I have a compose file like:

version: "3"

services:
  postgres:
    image: postgres:latest
    container_name: pg
    volumes:
      - /etc/passwd:/etc/passwd
      - /etc/shadow:/etc/shadow
      - /etc/pam.d/:/etc/pam.d/
    ports:
      - 5432:5432
    environment:
      POSTGRES_USERNAME: postgres
      POSTGRES_PASSWORD: postgres

My pg_hba.conf file is:

# "local" is for Unix domain socket connections only
local   all             all                                     trust
# PAM Authentication
host    all             all             0.0.0.0/0               pam
# IPv4 local connections:
host    all             all             127.0.0.1/32            trust
# IPv6 local connections:
host    all             all             ::1/128                 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     trust
host    replication     all             127.0.0.1/32            trust
host    replication     all             ::1/128                 trust

Under /var/lib/postgresql/data but I get the error when executing inside the container:

root@21cdb0e36245:/var/lib/postgresql/data# psql -h 127.0.0.1 -U testuser
Password for user testuser:
psql: error: FATAL:  PAM authentication failed for user "testuser"

Am I missing something in the volume mounts?