how to convert public key to string using openSSL api?

Question

I am able to retrieve the public key contents from a cert file using openssl by following the link http://fm4dd.com/openssl/certpubkey.htm

However, it prints the public key to stdout. I want to be able to store it in a string . Is there a way to get it into a char buffer or a string ?

The line PEM_write_bio_PUBKEY(outbio, pkey) prints to stdout.

Searched quite a bit, wasnt able to get what I wanted.

Any help will be appreciated, better if the code sample is provided as I'm running out of time.

Thanks in advance.

The code you link to sets up outbio to be stdout. I'd guess you just need to make a different output BIO instead? e.g. BIO_s_mem — Rup
– Rup, Commented Nov 16, 2018 at 17:05
Thanks, if you could provide some code to do that, would be helpful. — Abbas
– Abbas, Commented Nov 16, 2018 at 17:09

Abbas · Accepted Answer · 2018-11-16 17:15:33Z

2

Just replaced with EVP_PKEY *key in X509_to_PEM() signature and used PEM_write_bio_PUBKEY(bio, key) instead of PEM_write_bio_X509(bio, cert).

Worked !

answered Nov 16, 2018 at 17:15

Abbas

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