A TLS Banner Grabber, in Go
Modified for Invalid Subgroup scans by Valenta et. al
You will need to have a valid $GOPATH set up, for more information about $GOPATH, see https://golang.org/doc/code.html.
Once you have a working $GOPATH, run:
go get github.com/zmap/zgrab
This will install zgrab under $GOPATH/src/github.com/zmap/zgrab
$ cd $GOPATH/src/github.com/zmap/zgrab
$ go build
./zgrab --help
$ zmap -p 443 --output-fields=* | ztee results.csv | zgrab --port 443 --tls --http="/" --output-file=banners.json
zgrab requires go version of at least 1.6. Please note that this is newer than the version included in Ubuntu 14.04 apt repository. You can install ztee from ZMap Github repository at https://github.com/zmap/zmap.
If you are using ZGrab code in another Go program, import ZGrab using gopkg.in. ZGrab tends to be very unstable, API's may break at any time, so be sure to vendor ZGrab.
ZGrab is licensed under Apache 2.0 and ISC. For more information, see the LICENSE file.