encrypt/decrypt problem

Ivan wrote:

hi

i need to encrypt some fields in a table of my postgre db, my table is
named clients and the fields are "id", "name" and "password", i was
looking and i find the pgcrypto utility, i read something about the
pgcrypto functions and i see the "crypto" function and use it, well the
fields change and i supose that was encrypted... but how i could obtain
the decrypt info??? (i don't know it), well next i read about the
"encrypt-decrypt" function, maybe it is what i need i try to use the
encrypt function from the EMS PostgreSQL Manager (SQL editor) in that form

UPDATE tabla2 SET pass = encrypt(pass, 'iv', 'bf');

next i try:

encrypt(pass,'fooz','bf')

but either work... i don't find much examples about it, pls does anyone
have an idea of how i can implement the "encrypt-decrypt on my table???

You may be running into a "one-way-hash" encryption system - in which
when you use the crypto function, the data is stored in encrypted
format, with the idea that you take your input supplied, encrypt it, and
compare it to the field (containing the previously encrypted data) - if
it matches, then the "password" or whatever was entered correctly.

It typically isn't possible to reverse this one-way hash back to
plaintext easily.

Andrew Ayers

Ivan wrote:

hi

i need to encrypt some fields in a table of my postgre db, my table is
named clients and the fields are "id", "name" and "password", i was
looking and i find the pgcrypto utility, i read something about the
pgcrypto functions and i see the "crypto" function and use it, well
the fields change and i supose that was encrypted... but how i could
obtain the decrypt info??? (i don't know it), well next i read about
the "encrypt-decrypt" function, maybe it is what i need i try to use
the encrypt function from the EMS PostgreSQL Manager (SQL editor) in
that form

UPDATE tabla2 SET pass = encrypt(pass, 'iv', 'bf');

next i try:

encrypt(pass,'fooz','bf')

but either work... i don't find much examples about it, pls does
anyone have an idea of how i can implement the "encrypt-decrypt on my
table???

You may be running into a "one-way-hash" encryption system - in which
when you use the crypto function, the data is stored in encrypted
format, with the idea that you take your input supplied, encrypt it, and
compare it to the field (containing the previously encrypted data) - if
it matches, then the "password" or whatever was entered correctly.

It typically isn't possible to reverse this one-way hash back to
plaintext easily.

Andrew Ayers

thanks Andrew. well now i know that the crypt function is not what i need,
i need to encrypt all the fields of some tables not only the passwords, if
someone knows how to use the encrypt/decrypt function and could tell me
something, i will be grateful

ivan

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If the encrypt function is from the contribs, it CAN do reversible encryption, you just have to choose which encryption type you want to use. Please look in the archives at:

http://marc.theaimsgroup.com/?l=postgresql-general&w=2&r=1&s=encrypt+contrib&q=b

Ivan wrote:

thanx for the link!! it have cool info, well i learn how to use the
encrypt function:

UPDATE tabla2 SET lastname = encrypt('pass', 'pass', 'bf') where apellido
= 'noriega';

with that i change the fields i need to be encrypted... but there is
another problem... how i can obtain the decrypted data??, i suppose that i
need to use the "decrypt" function, i was trying to use it in that way:

SELECT decrypt('lastname', 'pass', 'bf') as "worked" from tabla2 where
apellido = 'noriega';

but i only obtain an encrypted value (different that the i already had in
the db)... anyone knows how to obtain the decrypted data???

ivan

If the encrypt function is from the contribs, it CAN do reversible
encryption, you just have to choose which encryption type you want to
use. Please look in the archives at:

http://marc.theaimsgroup.com/?l=postgresql-general&w=2&r=1&s=encrypt+contrib&q=b

Ivan wrote:

Ivan wrote:

hi

i need to encrypt some fields in a table of my postgre db, my table
is named clients and the fields are "id", "name" and "password", i
was looking and i find the pgcrypto utility, i read something about
the pgcrypto functions and i see the "crypto" function and use it,
well the fields change and i supose that was encrypted... but how i
could obtain the decrypt info??? (i don't know it), well next i read
about the "encrypt-decrypt" function, maybe it is what i need i try
to use the encrypt function from the EMS PostgreSQL Manager (SQL
editor) in that form

UPDATE tabla2 SET pass = encrypt(pass, 'iv', 'bf');

next i try:

encrypt(pass,'fooz','bf')

but either work... i don't find much examples about it, pls does
anyone have an idea of how i can implement the "encrypt-decrypt on my
table???

You may be running into a "one-way-hash" encryption system - in which
when you use the crypto function, the data is stored in encrypted
format, with the idea that you take your input supplied, encrypt it,
and
compare it to the field (containing the previously encrypted data) -
if it matches, then the "password" or whatever was entered correctly.

It typically isn't possible to reverse this one-way hash back to
plaintext easily.

Andrew Ayers

thanks Andrew. well now i know that the crypt function is not what i
need, i need to encrypt all the fields of some tables not only the
passwords, if someone knows how to use the encrypt/decrypt function
and could tell me something, i will be grateful

ivan

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keep reading, it takes a while to understand that library. Plus, you have to have it installed in your postgres installation. Apparently you do, since you were able to do 'encrypt'.

however, your arguments don't look right, which is why I suggest continued reading.

Ivan wrote:

read the file:

../contrib/pgcrypto/README.pgcrypto

Ivan wrote:

thanx Dennis G. for ur patience hehehe, i made the encryption/decryption,
this are the 2 sentences

for encrypt some field:

UPDATE tabla2 SET lastname = encrypt(lastname, 'pass', 'bf') where
apellido = 'noriega';

and for retrieve the decrypt info:

SELECT decrypt(lastname, 'pass', 'bf') as "LastName" from tabla2 where
apellido = 'noriega';

thanx all!!!!

ivan

You should try something like this:

This assumes your source to be encrypted is the last name:

lastname = encrypt( table.lastname::bytea, 'pass'::bytea,
'bf'::text)::bytea
(make sure your field is a bytea field!!)
decrypt(table.lastname::bytea, 'pass'::bytea, 'bf'::text)::bytea

I haven't done this before myself, but this looks like what the
documentation is trying to say.

Ivan wrote:

thanx for the link!! it have cool info, well i learn how to use the
encrypt function:

UPDATE tabla2 SET lastname = encrypt('pass', 'pass', 'bf') where
apellido = 'noriega';

with that i change the fields i need to be encrypted... but there is
another problem... how i can obtain the decrypted data??, i suppose
that i need to use the "decrypt" function, i was trying to use it in
that way:

SELECT decrypt('lastname', 'pass', 'bf') as "worked" from tabla2 where
apellido = 'noriega';

but i only obtain an encrypted value (different that the i already had
in the db)... anyone knows how to obtain the decrypted data???

ivan

If the encrypt function is from the contribs, it CAN do reversible
encryption, you just have to choose which encryption type you want to
use. Please look in the archives at:

http://marc.theaimsgroup.com/?l=postgresql-general&w=2&r=1&s=encrypt+contrib&q=b

Ivan wrote:

Ivan wrote:

hi

i need to encrypt some fields in a table of my postgre db, my table
is named clients and the fields are "id", "name" and "password", i
was looking and i find the pgcrypto utility, i read something about
the pgcrypto functions and i see the "crypto" function and use it,
well the fields change and i supose that was encrypted... but how i
could obtain the decrypt info??? (i don't know it), well next i
read about the "encrypt-decrypt" function, maybe it is what i need
i try to use the encrypt function from the EMS PostgreSQL Manager
(SQL editor) in that form

UPDATE tabla2 SET pass = encrypt(pass, 'iv', 'bf');

next i try:

encrypt(pass,'fooz','bf')

but either work... i don't find much examples about it, pls does
anyone have an idea of how i can implement the "encrypt-decrypt on
my table???

You may be running into a "one-way-hash" encryption system - in
which when you use the crypto function, the data is stored in
encrypted format, with the idea that you take your input supplied,
encrypt it, and
compare it to the field (containing the previously encrypted data) -
if it matches, then the "password" or whatever was entered
correctly.

It typically isn't possible to reverse this one-way hash back to
plaintext easily.

Andrew Ayers

thanks Andrew. well now i know that the crypt function is not what i
need, i need to encrypt all the fields of some tables not only the
passwords, if someone knows how to use the encrypt/decrypt function
and could tell me something, i will be grateful

ivan

--------------------------------------------
Free Webmail courtesy of http://www.444.net/

---------------------------(end of
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the mailing list cleanly

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broadcast)--------------------------- TIP 5: Have you checked our
extensive FAQ?

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