how to make curl accept secure cookies overt http connection

I am using curl to connect to an http server which sends back a secure flagged cookie, and I found out that curl doesn't handle such cookies (secure cookies received over http connection), in other words : even using -c cookieFile switch, such cookies are not saved.

A workaround is to use -D switch to save all headers then manually (externally to curl) read the cookie from the file and set it in the curl command to send it back to server.

I want to know if there is a possibility (may be I am missing some curl options) to make curl support such cookies ? I tried to look into curl manual but nothing useful to my use case.

Thanks in advance,

Solution

TL;DR: With recent versions of cURL it is no longer possible to save cookies with the secure attribute in conjunction with cookie related switches.

According the documentation cURL removed the ability to save cookies with the secure attribute in order to satisfy the RFC draft draft-ietf-httpbis-cookie-alone-01. This RFC draft mandates that secure cookies are only supposed to be handled, saved or overwritten by an HTTP client if said cookie was transferred over HTTPS.

I just stumbled over the exactly the same problem, so I can offer two alternatives:

use a cURL version before the feature was implemented
- cURL < v7.46.0
- see respective Github issue which led to this behaviour
dump the headers manually with curl -i or curl -D and extract the cookies
- example to save all secure cookies and save them in a file cookies.txt
```
 curl -i http://server.com | grep "Set-Cookie: " | sed 's/Set-Cookie: //g' > cookies.txt
```

Now, a cookie jar would be useless if you would not use the cookies inside. Especially regarding the second alternative, it may be necessary to remove the Secure attribute in order to make cURL send the saved cookies back to the web server.