mirror of
https://git.dn42.dev/dn42/registry.git
synced 2025-05-10 22:55:29 +08:00
Update sign-my-commit to handle more ssh key types and key-cert cases
This commit is contained in:
Simon Marsh
parent
3d6c9fe88d
commit
dd42fa0b39
1 changed files with 513 additions and 135 deletions
622
sign-my-commit
622
sign-my-commit
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@ -14,25 +14,53 @@
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usage()
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{
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echo "Usage: $0 [options] MNTNER"
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echo 'Generic options:'
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echo ' --pgp, sign using your PGP key'
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echo ' --ssh, sign using your ssh key'
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echo ' --push, force push result'
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echo ' --verify, check existing signature is correct'
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echo ' --commit, verify this specific commit'
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echo ' --help, display this message'
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echo 'SSH specific options:'
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echo ' --key, (required for signing) specify SSH private key file to use (public key file for signing via ssh-agent)'
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cat <<EOF
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This script can automatically sign commits using supported SSH or PGP
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authentication methods. Remember to push the new signature to the server
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after signing (using 'git push --force' or the --push option).
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The script will attempt to use the first available auth method, or you
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can force it to use PGP or SSH methods with the relevant options.
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For SSH signatures the script may be able to find your key via ssh-agent
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otherwise you must use the --key option to tell it which key to use.
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Usage: $0 [options] YOUR-MNTNER-MNT
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Generic options:
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--pgp, force signature to use a PGP key
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--ssh, force signature to use an SSH key
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--push, force push the result after signature and verification
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--verify, check an existing signature on the latest commit
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--commit <hash>, check the signature on a specific commit
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--help, display this message
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PGP specific options:
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--print <fprint>, specify fingerprint of GPG key to use if you
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don't want to use the first available key
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SSH specific options:
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--key <file>, specify SSH key file to use if not using ssh-agent
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or want to use a different key than the first available
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(this can be a public or private keyfile)
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--method <type>, either 'git' or 'comment' to force SSH signatures
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to use a specific method, defaults to 'git'
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EOF
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}
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##########################################################################
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# defaults
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DO_PUSH=0
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DO_SQUASH=1
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AUTH_METHOD=''
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MNTNER=''
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SSH_KEYFILE=''
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SSH_METHOD='git'
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GPG_PRINT=''
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VERIFY_ONLY=0
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COMMIT_SHA=''
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@ -52,17 +80,29 @@ do
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--push)
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DO_PUSH=1
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;;
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--key)
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shift
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SSH_KEYFILE="$1"
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--no-squash)
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DO_SQUASH=0
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;;
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--verify)
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VERIFY_ONLY=1
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;;
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--commit)
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shift
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VERIFY_ONLY=1
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COMMIT_SHA="$1"
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;;
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--key)
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shift
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SSH_KEYFILE="$1"
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;;
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--method)
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shift
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SSH_METHOD="$1"
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;;
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--print)
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shift
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GPG_PRINT="$1"
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;;
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--help)
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usage
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exit 0
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@ -72,8 +112,8 @@ do
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then
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MNTNER=$1
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else
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echo "ERROR: Unknown option: $1"
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usage
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>&2 echo "ERROR: Unknown option: $1"
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>&2 usage
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exit 1
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fi
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;;
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@ -84,14 +124,32 @@ do
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done
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##########################################################################
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# initial sanity checks
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# perform some initial sanity checks
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# check working directory
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if [ ! -d '.git' ] && [ ! -d 'data/mntner' ]
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then
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>&2 echo "ERROR: This script must be run in the root directory of a registry clone"
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exit 1
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fi
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# fill in the last commit if it wasn't specified already
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if [ -z "$COMMIT_SHA" ]
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then
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COMMIT_SHA=$(git log -n 1 --format=format:%H)
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fi
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# reset local git configuration
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git config --local --unset gpg.format
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git config --local --unset user.signingkey
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git config --local --unset gpg.ssh.allowedSignersFile
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# if verifying only, try to guess some info from the existing sig
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if [ "$VERIFY_ONLY" -eq 1 ]
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then
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if [ -z "$MNTNER" ]
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then
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MNTNER=$(git log ${COMMIT_SHA} -n 1 --format=format:%B | \
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MNTNER=$(git log "$COMMIT_SHA" -n 1 --format=format:%B | \
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grep '^### mntner:' | \
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cut -d':' -f2 | tr -d ' ')
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if [ -n "$MNTNER" ]
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@ -102,7 +160,7 @@ then
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if [ -z "$AUTH_METHOD" ]
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then
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AUTH_METHOD=$(git log ${COMMIT_SHA} -n 1 --format=format:%B | \
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AUTH_METHOD=$(git log "$COMMIT_SHA" -n 1 --format=format:%B | \
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grep '^### method:' | \
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cut -d':' -f2 | tr -d ' ')
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if [ -n "$AUTH_METHOD" ]
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@ -121,39 +179,55 @@ fi
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if [ ! -f "data/mntner/${MNTNER}" ]
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then
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echo "ERROR: mntner '${MNTNER}' not found"
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>&2 echo "ERROR: mntner '${MNTNER}' not found"
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exit 1
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fi
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# figure out the git version
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gitv_major=$(git --version | cut -d' ' -f3 | cut -d'.' -f1)
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gitv_minor=$(git --version | cut -d'.' -f2)
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# the script needs at least git 2.5
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if { [ "$gitv_major" -eq 2 ] && [ "$gitv_minor" -lt 5 ]; } || \
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[ "$gitv_major" -lt 2 ]
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then
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>&2 echo "ERROR: This script requires a git version 2.5"
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>&2 echo "---"
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>&2 git --version
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exit 1
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fi
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# if signing, check the repo is ready
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if [ "$VERIFY_ONLY" -ne 1 ]
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then
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# check for untracked or uncommitted changes
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if [ -n "$(git status --porcelain)" ]
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then
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echo "ERROR: git worktree has unstaged or uncommitted changes"
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echo "This script can only be run once your commit is completed"
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echo "---"
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git status
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>&2 echo "ERROR: git worktree has unstaged or uncommitted changes"
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>&2 echo "This script can only be run once your commit is completed"
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>&2 echo "---"
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>&2 git status
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exit 1
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fi
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# check that the commit has been squashed
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./squash-my-commits --verify
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if [ $? -ne 0 ]
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if [ "$DO_SQUASH" -eq 1 ]
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then
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echo "ERROR: Ensure your commits are squashed before signing"
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echo "Run the included script: ./squash-my-commits"
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if ! ./squash-my-commits --verify
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then
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>&2 echo "ERROR: Ensure your commits are squashed before signing"
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>&2 echo "Run the included script: ./squash-my-commits"
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exit 1
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fi
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fi
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# check for an existing signature
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git log -n 1 --format=format:%B 2>&1 | grep '^### DN42 Signature' > /dev/null
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if [ $? -eq 0 ]
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if git log -n 1 --format=format:%B 2>&1 | grep '^### DN42 Signature' > /dev/null
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then
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echo "ERROR: The last commit appears to already be signed"
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echo "---"
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git log -n 1 --show-signature
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>&2 echo "ERROR: The last commit appears to already be signed"
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>&2 echo "---"
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>&2 git log -n 1 --show-signature
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exit 1
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fi
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@ -162,36 +236,77 @@ fi
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##########################################################################
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# helper functions
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guess_auth_method()
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# guess a signature method based on the first auth attribute in a MNTNER
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guess_mntner_method()
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{
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# look for the first auth method in the mntner object
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method=$(grep '^auth' "data/mntner/${MNTNER}" | \
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head -n 1 | tr -s ' ' | cut -d' ' -f2 | cut -d'-' -f1)
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# didn't find anything ?
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if [ -z "$method" ]
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then
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echo "Unable to find mntner auth method for ${MNTNER}"
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echo "Try specifying the method manually"
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usage
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exit 1
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fi
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method=$(grep '^auth:' "data/mntner/${MNTNER}" | head -n 1 | cut -c21- | cut -d' ' -f1)
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case "$method" in
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pgp)
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AUTH_METHOD='pgp'
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pgp-fingerprint|PGPKEY-*)
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echo 'pgp'
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;;
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PGPKEY)
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AUTH_METHOD='pgp'
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ssh-*|sk-ssh-*|ecdsa-*|sk-ecdsa-*)
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echo "ssh"
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;;
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ssh)
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AUTH_METHOD='ssh'
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'')
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>&2 echo "ERROR: Unable to find any auth attributes for $MNTNER"
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exit 1
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;;
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*)
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echo "ERROR: Auth method is unknown or unimplemented"
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>&2 echo "ERROR: Unknown or unimplemented auth method '$method'"
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>&2 echo 'Check the auth attribute is actually supported '
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>&2 echo 'or specify the signature type manually.'
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exit 1
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;;
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esac
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}
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##########################################################################
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#
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# PGP Section - functions for signing and verify PGP signatures
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#
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##########################################################################
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# PGP Helper functions
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# create a list of authorised PGP fingerprints
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get_pgp_prints()
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{
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pgp_prints=$(mktemp)
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# cut auth methods from mntner
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grep '^auth:' "data/mntner/${MNTNER}" | cut -c21- | \
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while read -r auth_method auth_data
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do
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case "$auth_method" in
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pgp-fingerprint)
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# use the fingerprint directly
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echo "$auth_data" | \
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tr '[:lower:]' '[:upper:]' >> "$pgp_prints"
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;;
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PGPKEY-*)
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if [ ! -f "data/key-cert/$auth_method" ]
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then
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>&2 echo "ERROR: failed to find key-cert object: $auth_method"
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rm "$pgp_prints"
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exit 1
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fi
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# get the fingerprint from key-cert file
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grep '^fingerpr:' "data/key-cert/$auth_method" | \
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cut -c21- | tr -d ' ' | \
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tr '[:lower:]' '[:upper:]' >> "$pgp_prints"
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;;
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esac
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done
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if [ ! -s "$pgp_prints" ]
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then
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>&2 echo "ERROR: failed to find any pgp fingerprints for $MNTNER"
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rm "$pgp_prints"
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exit 1
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fi
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echo "$pgp_prints"
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}
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##########################################################################
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# PGP signing function
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@ -199,15 +314,28 @@ guess_auth_method()
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sign_pgp()
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{
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# check first if there is already a signature
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git log -n 1 --show-signature | grep "^gpg" > /dev/null 2>&1
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if [ $? -eq 0 ]
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if git log -n 1 --show-signature | grep "^gpg" > /dev/null 2>&1
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then
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echo "ERROR: The last commit appears to already be signed."
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echo "---"
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git log -n 1 --show-signature
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>&2 echo "ERROR: The last commit appears to already be signed."
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>&2 echo "---"
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>&2 git log -n 1 --show-signature
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exit 1
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fi
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# if the fingerprint wasn't specified, obtain from the MNTNER
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if [ -z "$GPG_PRINT" ]
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then
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pgp_prints=$(get_pgp_prints)
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GPG_PRINT=$(head -n 1 "$pgp_prints")
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rm "$pgp_prints"
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fi
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echo "PGP signing using fingerprint: $GPG_PRINT"
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# configure local git for pgp signing
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git config --local --unset gpg.format
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git config --local user.signingKey "$GPG_PRINT"
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# create a new comment with some additional metadata
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comment="$(git log -n 1 --format=format:%B)
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@ -217,19 +345,14 @@ sign_pgp()
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"
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# PGP signing is straightforward
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git commit --amend --no-edit -S -m "$comment"
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# assuming it's actually configured properly ....
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if [ $? -ne 0 ]
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if ! git commit --amend --no-edit -S -m "$comment"
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then
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echo "ERROR: failed to sign commit"
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echo "Have you configured git with your PGP key ?"
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echo "For example, to configure your key globally:"
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echo " - Find your key using: gpg --list-keys"
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echo " - Then add it to git: " \
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"git config --global user.signingkey <FPRINT>"
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>&2 echo "ERROR: failed to sign commit"
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exit 1
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fi
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# update the COMMIT_SHA for the verification phase
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COMMIT_SHA=$(git log -n 1 --format=format:%H)
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}
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##########################################################################
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@ -239,128 +362,375 @@ verify_pgp()
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{
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echo "Verifying PGP signature"
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# find the current commit hash
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hash=$(git log ${COMMIT_SHA} -n 1 --format=format:%H)
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# requires git 2.5
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git verify-commit "$hash"
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if [ $? -ne 0 ]
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if ! git verify-commit "$COMMIT_SHA"
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then
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echo "ERROR: failed to verify PGP signature"
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>&2 echo "ERROR: failed to verify PGP signature"
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exit 1
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fi
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echo " - PGP signature verified ok"
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# create a list of authorised pgp fingerprints
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valid_prints=$(get_pgp_prints)
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# extract the fingerprint of the key that was successful
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prints=$(git verify-commit --raw "$hash" 2>&1 | \
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prints=$(git verify-commit --raw "$COMMIT_SHA" 2>&1 | \
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grep "VALIDSIG" | cut -f3,12 -d' ')
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for print in $prints
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do
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grep "^auth" data/mntner/${MNTNER} | grep -i $print > /dev/null 2>&1
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if [ $? -eq 0 ]
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if grep "$print" "$valid_prints" > /dev/null 2>&1
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then
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echo " - matched with auth attribute for $MNTNER"
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echo "Matched fingerprint with auth attribute for $MNTNER"
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echo "Successfully verified PGP signature"
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rm "$valid_prints"
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return
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fi
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done
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echo "ERROR: unable to match key fingerprint with mntner: $MNTNER"
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>&2 echo "ERROR: unable to match key fingerprint with mntner: $MNTNER"
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rm "$valid_prints"
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exit 1
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}
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##########################################################################
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#
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# SSH Section - functions for signing and verify SSH signatures
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#
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##########################################################################
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# SSH helper functions
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# return only ssh auth methods for mntner
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filter_ssh_auths()
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{
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grep '^auth:' "data/mntner/${MNTNER}" | cut -c21- | \
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while read -r line
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do
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case "$line" in
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ssh-*|sk-ssh-*|ecdsa-*|sk-ecdsa-*)
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echo "$line"
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;;
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esac
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done
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}
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# create an allowed signers file using the mntner auth attributes
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get_allowed_signers()
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{
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allowed=$(mktemp)
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filter_ssh_auths | sed "s/^/${MNTNER} /" > "$allowed"
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echo "$allowed"
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}
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# try and find a suitable keyfile that we can sign with
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check_keyfile()
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{
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pubkeyfile=''
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# guess the public key if a keyfile wasn't specified
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if [ -z "$SSH_KEYFILE" ]
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then
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pubkeyfile=$(mktemp)
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echo "Obtaining public key from $MNTNER auth attributes"
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# get the public key from mntner auth records
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filter_ssh_auths | head -n 1 > "$pubkeyfile"
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if [ ! -s "$pubkeyfile" ]
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then
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>&2 echo "ERROR: Unable to auto determine SSH public key"
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>&2 echo "Try specifying the key directly using --key"
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rm "$pubkeyfile"
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exit 1
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fi
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# check if the pubkey is available in agent
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pubkey=$(tr -s ' ' < "$pubkeyfile" | cut -d' ' -f1,2)
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if ssh-add -L | grep "^$pubkey" > /dev/null 2>&1
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then
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# key was found in agent ok
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SSH_KEYFILE="$pubkeyfile"
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else
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# no key found in agent, clean up the keyfile first
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rm "$pubkeyfile"
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pubkeyfile=''
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|
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if [ -d "${HOME}/.ssh" ]
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then
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# as a last resort, try scanning the 'usual' ssh
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||||
# directory to find the key in there
|
||||
|
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SSH_KEYFILE=$(grep -l "^$pubkey" "${HOME}"/.ssh/*.pub)
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fi
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|
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if [ -n "$SSH_KEYFILE" ]
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then
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>&2 echo "Found SSH key in: $SSH_KEYFILE"
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else
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# all attempts failed
|
||||
>&2 cat <<EOF
|
||||
ERROR: Unable to identify public key in ssh-agent or home directory
|
||||
- When auto detecting the public key from you mntner object it
|
||||
- is required that the private key is available in ssh-agent or
|
||||
- in your ${HOME}/.ssh/ directory.
|
||||
- Please add your key to ssh-agent or use the --key option to
|
||||
- specify where the private key is directly.
|
||||
---
|
||||
Pubkey: $pubkey
|
||||
EOF
|
||||
exit 1
|
||||
fi
|
||||
fi
|
||||
fi
|
||||
|
||||
# try to validate the public key
|
||||
if ! pubkey=$(ssh-keygen -l -f "$SSH_KEYFILE")
|
||||
then
|
||||
>&2 echo "ERROR: $SSH_KEYFILE doesn't look like a valid SSH key"
|
||||
>&2 echo "Try specifying the public or private key directly using --key"
|
||||
>&2 echo "File contents:"
|
||||
>&2 cat "$SSH_KEYFILE"
|
||||
if [ -n "$pubkeyfile" ]; then rm "$pubkeyfile"; fi
|
||||
exit 1
|
||||
fi
|
||||
|
||||
echo "Using: $pubkey"
|
||||
}
|
||||
|
||||
##########################################################################
|
||||
# SSH signing function
|
||||
|
||||
sign_ssh()
|
||||
# SSH signature using git signatures
|
||||
sign_ssh_git()
|
||||
{
|
||||
# check for ssh-keygen signing capability
|
||||
ssh-keygen -Y sign 2>&1 | grep 'missing namespace' > /dev/null
|
||||
if [ $? -ne 0 ]
|
||||
check_keyfile
|
||||
|
||||
# configure local git signing
|
||||
git config --local gpg.format ssh
|
||||
git config --local user.signingKey "$SSH_KEYFILE"
|
||||
|
||||
# create a new comment with some additional metadata
|
||||
comment="$(git log -n 1 --format=format:%B)
|
||||
|
||||
### DN42 Signature
|
||||
### method: ssh-git
|
||||
### mntner: $MNTNER
|
||||
"
|
||||
|
||||
# the signature is now straightforward
|
||||
git commit --amend --no-edit -S -m "$comment"
|
||||
result=$?
|
||||
|
||||
# clean up pubkeyfile first
|
||||
if [ -n "$pubkeyfile" ]; then rm "$pubkeyfile"; fi
|
||||
|
||||
# was there an error ?
|
||||
if [ "$result" -ne 0 ]
|
||||
then
|
||||
echo "ERROR: This script requires the key signing capability " \
|
||||
"from OpenSSH ssh-keygen > version 8"
|
||||
echo "---"
|
||||
ssh -V
|
||||
>&2 echo "ERROR: failed to sign commit"
|
||||
>&2 echo " - Try specifying your key using --key"
|
||||
>&2 echo " - or adding your key to ssh-agent"
|
||||
exit 1
|
||||
fi
|
||||
|
||||
if [ -z "$SSH_KEYFILE" ]
|
||||
then
|
||||
echo "ERROR: You must specify your SSH private key " \
|
||||
"using --key"
|
||||
exit 1
|
||||
fi
|
||||
# update the COMMIT_SHA for the verification phase
|
||||
COMMIT_SHA=$(git log -n 1 --format=format:%H)
|
||||
}
|
||||
|
||||
# find the current commit hash
|
||||
hash=$(git log -n 1 --format=format:%H)
|
||||
|
||||
# SSH signature by adding in to the comment
|
||||
sign_ssh_comment()
|
||||
{
|
||||
check_keyfile
|
||||
|
||||
# create the signature
|
||||
sig=$(echo "$hash" | ssh-keygen -Y sign -n dn42 -f "$SSH_KEYFILE")
|
||||
sig=$(echo "$COMMIT_SHA" | \
|
||||
ssh-keygen -Y sign -n dn42 -f "$SSH_KEYFILE")
|
||||
result=$?
|
||||
|
||||
# clean up pubkeyfile first
|
||||
if [ -n "$pubkeyfile" ]; then rm "$pubkeyfile"; fi
|
||||
|
||||
# check for errors
|
||||
if [ "$result" -ne 0 ]
|
||||
then
|
||||
>&2 echo "ERROR: ssh-keygen signing failed"
|
||||
>&2 echo " - Try specifying your key using --key"
|
||||
>&2 echo " - or adding the key to ssh-agent"
|
||||
if [ -n "$pubkeyfile" ]; then rm "$pubkeyfile"; fi
|
||||
exit 1
|
||||
fi
|
||||
|
||||
# create a comment including the signature
|
||||
comment="$(git log -n 1 --format=format:%B)
|
||||
|
||||
### DN42 Signature
|
||||
### method: ssh
|
||||
### mntner: $MNTNER
|
||||
### text: $hash
|
||||
### text: $COMMIT_SHA
|
||||
$sig
|
||||
"
|
||||
|
||||
# update the commit with the sig
|
||||
git commit --amend --no-edit -m "$comment"
|
||||
|
||||
# update the COMMIT_SHA for the verification phase
|
||||
COMMIT_SHA=$(git log -n 1 --format=format:%H)
|
||||
}
|
||||
|
||||
sign_ssh()
|
||||
{
|
||||
# check for ssh-keygen signing capability
|
||||
if ! ssh-keygen -Y sign 2>&1 | grep 'missing namespace' > /dev/null
|
||||
then
|
||||
>&2 cat <<EOF
|
||||
ERROR: This script requires the key signing capability from
|
||||
OpenSSH ssh-keygen that was introduced in version 8.
|
||||
|
||||
If you are unable to upgrade ssh-keygen you must use one of the
|
||||
manual signing methods detailed in the dn42 wiki:
|
||||
|
||||
https://dn42.dev/howto/Registry-Authentication
|
||||
|
||||
---
|
||||
EOF
|
||||
>&2 ssh -V
|
||||
exit 1
|
||||
fi
|
||||
|
||||
# if we have git >= 2.34 the commit can be git signed
|
||||
if [ "$SSH_METHOD" != "comment" ]
|
||||
then
|
||||
if { [ "$gitv_major" -eq 2 ] && [ "$gitv_minor" -ge 34 ]; } || \
|
||||
[ "$gitv_major" -gt 2 ]
|
||||
then
|
||||
echo "Detected git version >= 2.34, using git SSH signature"
|
||||
sign_ssh_git
|
||||
return
|
||||
else
|
||||
echo "Detected git version < 2.34, cannot sign using git"
|
||||
fi
|
||||
fi
|
||||
|
||||
echo "Defaulting to comment based signature"
|
||||
sign_ssh_comment
|
||||
}
|
||||
|
||||
##########################################################################
|
||||
# verify SSH signature
|
||||
|
||||
verify_ssh()
|
||||
# verify a git based SSH signature
|
||||
verify_ssh_git()
|
||||
{
|
||||
echo "Verifying SSH signature"
|
||||
echo "Verifying SSH signature in git"
|
||||
|
||||
# create a temporary files for the 'allowed' keys file and signature
|
||||
afile=$(mktemp)
|
||||
sfile=$(mktemp)
|
||||
# check git version
|
||||
if { [ "$gitv_major" -eq 2 ] && [ "$gitv_minor" -lt 34 ]; } || \
|
||||
[ "$gitv_major" -lt 2 ]
|
||||
then
|
||||
>&2 echo "Detected git version < 2.34, unable to verify git signatures"
|
||||
>&2 echo "- Upgrade git to at least version 2.34"
|
||||
exit 1
|
||||
fi
|
||||
|
||||
# extract and reformat the temp keys in to the allowed file
|
||||
grep '^auth' "data/mntner/${MNTNER}" | tr -s ' ' | cut -d' ' -f2- | \
|
||||
grep '^ssh-' | sed "s/^/${MNTNER} /" > "$afile"
|
||||
# create an allowed signers file and configure it in git
|
||||
allowed=$(get_allowed_signers)
|
||||
git config --local gpg.ssh.allowedSignersFile "$allowed"
|
||||
|
||||
# extract the signed text from the git comment
|
||||
text=$(git log ${COMMIT_SHA} -n 1 --format=format:%B | grep '^### text:' |
|
||||
cut -d':' -f2 | tr -d ' ')
|
||||
# signature can now be verified similar to pgp case
|
||||
|
||||
# extract the SSH signature from the comment
|
||||
# find the current commit hash
|
||||
git verify-commit "$COMMIT_SHA"
|
||||
result=$?
|
||||
|
||||
# clean up allowed signers file before doing anything else
|
||||
git config --local --unset gpg.ssh.allowedSignersFile
|
||||
rm "$allowed"
|
||||
|
||||
# did the signature successfully validate ?
|
||||
if [ "$result" -ne 0 ]
|
||||
then
|
||||
>&2 echo "ERROR: failed to verify SSH signature"
|
||||
exit 1
|
||||
fi
|
||||
|
||||
echo "SSH signature verified ok"
|
||||
}
|
||||
|
||||
# verify a comment based SSH signature
|
||||
verify_ssh_comment()
|
||||
{
|
||||
echo "Verifying SSH signature comment"
|
||||
|
||||
# create the allowed signers file
|
||||
allowed=$(get_allowed_signers)
|
||||
|
||||
# extract the text that was signed from the git comment
|
||||
text=$(git log "$COMMIT_SHA" -n 1 --format=format:%B | \
|
||||
grep '^### text:' | cut -d':' -f2 | tr -d ' ')
|
||||
|
||||
# also extract the SSH signature from the comment
|
||||
signature=$(mktemp)
|
||||
begin="-----BEGIN SSH SIGNATURE-----"
|
||||
end="-----END SSH SIGNATURE-----"
|
||||
git log ${COMMIT_SHA} -n 1 --format=format:%B | \
|
||||
sed "/^$begin\$/,/^$end\$/!d" > "$sfile"
|
||||
git log "$COMMIT_SHA" -n 1 --format=format:%B | \
|
||||
sed "/^$begin\$/,/^$end\$/!d" > "$signature"
|
||||
|
||||
# and finally verify
|
||||
echo "$text" | ssh-keygen -Y verify -f "$afile" \
|
||||
-n dn42 -I $MNTNER -s "$sfile"
|
||||
# grab the result and then clean up
|
||||
# now we can verify the signature
|
||||
echo "$text" | ssh-keygen -Y verify -f "$allowed" \
|
||||
-n dn42 -I "$MNTNER" -s "$signature"
|
||||
# grab the result and clean up before doing anything else
|
||||
result=$?
|
||||
rm -f "$afile" "$sfile"
|
||||
rm "$allowed" "$signature"
|
||||
|
||||
# did it work ?
|
||||
if [ $result -eq 0 ]
|
||||
if [ "$result" -eq 0 ]
|
||||
then
|
||||
echo "Successfully verified SSH sigature"
|
||||
else
|
||||
echo "ERROR: signature verification failed"
|
||||
>&2 echo "ERROR: signature verification failed"
|
||||
exit 1
|
||||
fi
|
||||
}
|
||||
|
||||
# SSH verify wrapper
|
||||
verify_ssh()
|
||||
{
|
||||
# determine signature type from log comment
|
||||
method=$(git log "$COMMIT_SHA" -n 1 --format=format:%B | \
|
||||
grep '^### method:' | cut -d':' -f2 | tr -d ' ')
|
||||
case "$method" in
|
||||
'ssh')
|
||||
verify_ssh_comment
|
||||
;;
|
||||
'ssh-git')
|
||||
verify_ssh_git
|
||||
;;
|
||||
'')
|
||||
echo "WARNING: No dn42 signature found, attempting git based verification"
|
||||
verify_ssh_git
|
||||
;;
|
||||
*)
|
||||
>&2 echo "ERROR: commit does not appear to be signed by SSH"
|
||||
>&2 echo "Found signature method: $method"
|
||||
exit 1
|
||||
;;
|
||||
esac
|
||||
}
|
||||
|
||||
##########################################################################
|
||||
# body of the script starts here
|
||||
#
|
||||
# Script body - the script resumes here
|
||||
#
|
||||
##########################################################################
|
||||
|
||||
if [ -z "$AUTH_METHOD" ]
|
||||
then
|
||||
echo "Attempting to guess auth method from the mntner object"
|
||||
guess_auth_method
|
||||
if [ "$VERIFY_ONLY" -ne 1 ]
|
||||
then
|
||||
echo "Attempting to guess signature method from mntner object"
|
||||
AUTH_METHOD=$(guess_mntner_method)
|
||||
fi
|
||||
fi
|
||||
|
||||
# decide what to do
|
||||
|
|
@ -373,7 +743,7 @@ case "$AUTH_METHOD" in
|
|||
fi
|
||||
verify_pgp
|
||||
;;
|
||||
ssh)
|
||||
ssh|ssh-git)
|
||||
if [ "$VERIFY_ONLY" -ne 1 ]
|
||||
then
|
||||
echo "Signing using SSH key"
|
||||
|
|
@ -381,8 +751,14 @@ case "$AUTH_METHOD" in
|
|||
fi
|
||||
verify_ssh
|
||||
;;
|
||||
'')
|
||||
>&2 echo "ERROR: Unable to automatically determine signing method"
|
||||
>&2 echo "Use the --ssh or --pgp options to force a particular method"
|
||||
exit 1
|
||||
;;
|
||||
*)
|
||||
echo "ERROR: Unknown or unimplemented auth method: $AUTH_METHOD"
|
||||
>&2 echo "ERROR: Unknown or unimplemented auth method: $AUTH_METHOD"
|
||||
>&2 echo "Use the --ssh or --pgp options to force a particular method"
|
||||
exit 1
|
||||
;;
|
||||
esac
|
||||
|
|
@ -401,7 +777,9 @@ then
|
|||
echo 'Force pushing changes'
|
||||
git push --force
|
||||
else
|
||||
echo '---'
|
||||
echo 'Remember to push your changes using: git push --force'
|
||||
echo '---'
|
||||
fi
|
||||
|
||||
exit 0
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue