Subject: Re: Password encryption
To: pgsql-admin@lists.postgresql.org
References: 
 <CAKUuFd5=VwmFfj4Q3HK2s9EiEycqxQ-BPCdcKniWVWn4q=d0PA@mail.gmail.com>
From: Ron <ronljohnsonjr@gmail.com>
Message-ID: <b2d67a07-4766-ac8c-8445-79aae8bea572@gmail.com>
Date: Sun, 15 Apr 2018 20:16:04 -0500
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On 04/15/2018 07:22 PM, Azimuddin Mohammed wrote:
> Hello,
> Is there a way I can encrypt the default password column of db user 
> password. I know by default the password is encrypted as md5, can we 
> encrypt that of shadow column for password?

MD5 is a *one-way hash*, not an encryption scheme.  Thus, the password 
cannot be reverse-computed from the MD5 hash value.  So, you're (kinda) 
safe, although an attacker could determine the password through brute-force 
calculation of hashes.


-- 
Angular momentum makes the world go 'round.

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    On 04/15/2018 07:22 PM, Azimuddin Mohammed wrote:<br>
    <blockquote type="cite"
cite="mid:CAKUuFd5=VwmFfj4Q3HK2s9EiEycqxQ-BPCdcKniWVWn4q=d0PA@mail.gmail.com">
      <div dir="auto">Hello,
        <div dir="auto">Is there a way I can encrypt the default
          password column of db user password. I know by default the
          password is encrypted as md5, can we encrypt that of shadow
          column for password?</div>
      </div>
    </blockquote>
    <br>
    MD5 is a <b>one-way hash</b>, not an encryption scheme.  Thus, the
    password cannot be reverse-computed from the MD5 hash value.  So,
    you're (kinda) safe, although an attacker could determine the
    password through brute-force calculation of hashes.<br>
    <br>
    <br>
    <div class="moz-signature">-- <br>
      Angular momentum makes the world go 'round.</div>
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