Yeah, it sounds correct. But since it’s an old application code & we are not sure why was it done so, we are little worried to change.
Can you please take a look the attachment which has the complete flow, and provide your views which helps us to change it to PEM_read_PrivateKey() or variants as you suggested
Regards,
Sunil
From: Thulasi Goriparthi <thulasi.goriparthi@xxxxxxxxx>
Sent: 29 January 2021 17:24
To: Narayana, Sunil Kumar <sanarayana@xxxxxxxx>
Cc: openssl-users@xxxxxxxxxxx
Subject: Re: <Replacement for RSA_public_decrypt>
NOTICE: This email was received from an EXTERNAL sender
Isn't it obvious to use PEM_read_PrivateKey() or variants to load the private key as EVP_PKEY
and use EVP_PKEY_decrypt* as specified in https://www.openssl.org/docs/man1.0.2/man3/EVP_PKEY_decrypt.html ?
Thanks,
Thulasi.
On Fri, 29 Jan 2021 at 16:59, Narayana, Sunil Kumar <sanarayana@xxxxxxxx> wrote:
Hi Thulasi,
Currently in (1.0.1) we are following the following sequence, which now need to replace with EVP.
Current sequence
//to create RSA pubkey
rsa = PEM_read_bio_RSA_PUBKEY(keybio, NULL, NULL, NULL); // !!!
//to decrypt using RSA utility
RSA_public_decrypt(len, (unsigned char*)buffer,decrypted,rsa, RSA_PKCS1_PADDING) ;
As you mentioned , if we use PEM_read_bio_PUBKEY to get EVP_PKEY, it will be a pubkey right ? but in order to decrypt as per the example in https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_decrypt_init.html
We need to use an RSA private key
Please suggest.
Regards,
Sunil
From: Thulasi Goriparthi <thulasi.goriparthi@xxxxxxxxx>
Sent: 29 January 2021 13:07
To: Narayana, Sunil Kumar <sanarayana@xxxxxxxx>
Cc: openssl-users@xxxxxxxxxxx
Subject: Re: <Replacement for RSA_public_decrypt>
NOTICE: This email was received from an EXTERNAL sender
Hope, you are referring to https://www.openssl.org/docs/man1.0.2/man3/EVP_PKEY_encrypt.html
Use PEM_read_bio_PUBKEY to get EVP_PKEY.
eng is for engine reference. If you have no engine, it can be NULL.
Thanks,
Thulasi.
On Fri, 29 Jan 2021 at 10:13, Narayana, Sunil Kumar <sanarayana@xxxxxxxx> wrote:
Dear Openssl team,
While migrating from 1.0.2 to 3.0 we observe that RSA_public_decrypt() API been deprecated in 3.0.
We referred the example provided in man page but we are not clear in generating the initial ‘key’ required to create CTX.
Please suggest on (key , eng) params to proceed
Also currently we are using PEM_read_bio_RSA_PUBKEY() to generate RSA, I think this might not require in case of EVP, please suggest.
/*
* NB: assumes key, eng, in, inlen are already set up
* and that key is an RSA private key
*/
ctx = EVP_PKEY_CTX_new(key, eng);
Regards,
Sunil
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Notice: This e-mail together with any attachments may contain information of Ribbon Communications Inc. and its Affiliates that is confidential and/or proprietary for the sole use of the intended recipient. Any review, disclosure, reliance or distribution by others or forwarding without express permission is strictly prohibited. If you are not the intended recipient, please notify the sender immediately and then delete all copies, including any attachments.
I am not sure why the code you have shared is trying to decrypt the signature.
If it is done as part of signature verification, don't do this. Use the actual EVP_PKEY_verify API with corresponding public key.
If you certainly need the decrypted signature, you should do public encryption with NONE padding.
A Private key is not necessary.
Thanks,
Thulasi
On Fri, 29 Jan 2021 at 17:47, Narayana, Sunil Kumar <sanarayana@xxxxxxxx> wrote:
