I'm attempting to sign some content using a certificate with the following command which uses process substitution to deliver the certificate content to openssl (since it requires either a file or uri):
echo "something to sign" \
| openssl dgst -binary -sha256 -sign <(echo "certificate to sign with")
This runs flawlessly in zsh but when I try to run this via bash I get an error:
Could not read private key from /dev/fd/63
What am I doing wrong here?
It turns out this was all due to new line \n sequences in the credentials payload and echo requiring interpretation of backslash escapes to be turned on when using bash.
echo "something to sign" \
| openssl dgst -binary -sha256 -sign <(echo -e "certificate to sign with")
When using zsh the backslashes are seemingly interpreted automatically making me believe the issue was with the process substitution but not the contents of the credentials.
It feels silly to not have realized this sooner, but I hope this will help someone in the future also gets lost in the weeds.