Update repository to reflect required min go version of 1.20

Resolves #1414

.github/workflows/go.yml

@@ -10,10 +10,11 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        # starting with go 1.24 the GODEBUG=x509sha1=1 flag has been removed. 
+        # starting with go 1.24 the GODEBUG=x509sha1=1 flag has been removed.
         # many tests rely on sha1 certificates. After resolving #1413 we can
-        # run these on stable and old stable again.
-        go: ['1.23', '1.22']
+        # run these on stable and oldstable again. Min version (1.20) can
+        # always be run.
+        go: ['1.23', '1.22', '1.20']
     services:
       # Label used to access the service container
       postgres:
@@ -76,7 +77,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
         with:
-          go-version: 1.18
+          go-version: 1.20
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v6
         with:

Dockerfile.alpine

@@ -1,4 +1,4 @@
-FROM golang:1.16.15-alpine3.15@sha256:9743f230f26d1e300545f0330fd4a514f554c535d967563ee77bf634906502b6 as builder
+FROM golang:1.20-alpine AS builder
 
 WORKDIR /workdir
 COPY . /workdir

README.md

@@ -8,7 +8,7 @@
 
 CFSSL is CloudFlare's PKI/TLS swiss army knife. It is both a command line
 tool and an HTTP API server for signing, verifying, and bundling TLS
-certificates. It requires Go 1.16+ to build.
+certificates. It requires Go 1.20+ to build.
 
 Note that certain linux distributions have certain algorithms removed
 (RHEL-based distributions in particular), so the golang from the
@@ -30,7 +30,7 @@ CFSSL consists of:
 ### Building
 
 Building cfssl requires a
-[working Go 1.16+ installation](http://golang.org/doc/install).
+[working Go 1.20+ installation](http://golang.org/doc/install).
 
 ```
 $ git clone [email protected]:cloudflare/cfssl.git
@@ -61,32 +61,9 @@ You can set the `GOOS` and `GOARCH` environment variables to have Go cross compi
 
 ### Installation
 
-Installation requires a [working Go 1.16+ installation](http://golang.org/doc/install).
+Installation requires a [working Go 1.20+ installation](http://golang.org/doc/install).
 Alternatively, [prebuilt binaries are available](https://github.com/cloudflare/cfssl/releases)
 
-```
-$ go get github.com/cloudflare/cfssl/cmd/cfssl
-```
-
-will download, build, and install the CFSSL tool.
-
-To install any of the other utility programs that are
-in this repo (for instance `cfssljson` in this case):
-
-```
-$ go get github.com/cloudflare/cfssl/cmd/cfssljson
-```
-
-This will download, build, and install the CFSSLJSON tool.
-
-And to simply install __all__ of the programs in this repo:
-
-```
-$ go get github.com/cloudflare/cfssl/cmd/...
-```
-
-if you are above go 1.18:
-
 ```
 $ go install github.com/cloudflare/cfssl/cmd/...@latest
 ```

go.mod

@@ -1,6 +1,6 @@
 module github.com/cloudflare/cfssl
 
-go 1.18
+go 1.20
 
 require (
 	bitbucket.org/liamstask/goose v0.0.0-20150115234039-8488cc47d90c