posts/2021-05-31+9front+tls+Part+2


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In my last post I covered  9front server side tls - now we begin the client side.

I found that most of the user space tls stuff is not *that* interesting or it's stuff for another post.
So, we'll jump right in to C

*Thinks back to earlier today*

orthanc% ./sha1sum -3 256 /amd64/9pc64
sha1sum 238299: suicide: sys: trap: fault write addr=0x0 pc=0x00006afb

*screams*

Ok, but thats for the next post. Back to tls. This is scary easy stuff.

"dial" your server

int fd = dial("tcp!server!port")

Create a tls connection, this lets you seek for info on your connection (say, certs)

conn = (TLSconn*)mallocz(sizeof *conn, 1);

start the tls "pipe"

fd = tlsClient(fd, conn);

Now you can read and write using that fd like you would on the server side, but you should check those certs

if(!okCertificate(conn->cert, conn->certlen, table))
	sysfatal("suspect server: %r");

I do know that there is no real CA validation as of now, I may work on fixing that. 

Ok, that's all I have for now, see you next post.

--
Fulton