gentoo resync : 25.11.2020

1 files changed, 271 insertions, 0 deletions

diff --git a/eclass/verify-sig.eclass b/eclass/verify-sig.eclass
new file mode 100644
index 000000000000..e3ef7f240283
--- /dev/null
+++ b/eclass/verify-sig.eclass
@@ -0,0 +1,271 @@
+# Copyright 2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+# @ECLASS: verify-sig.eclass
+# @MAINTAINER:
+# Michał Górny <mgorny@gentoo.org>
+# @SUPPORTED_EAPIS: 7
+# @BLURB: Eclass to verify upstream signatures on distfiles
+# @DESCRIPTION:
+# verify-sig eclass provides a streamlined approach to verifying
+# upstream signatures on distfiles.  Its primary purpose is to permit
+# developers to easily verify signatures while bumping packages.
+# The eclass removes the risk of developer forgetting to perform
+# the verification, or performing it incorrectly, e.g. due to additional
+# keys in the local keyring.  It also permits users to verify
+# the developer's work.
+#
+# To use the eclass, start by packaging the upstream's key
+# as app-crypt/openpgp-keys-*.  Then inherit the eclass, add detached
+# signatures to SRC_URI and set VERIFY_SIG_OPENPGP_KEY_PATH.  The eclass
+# provides verify-sig USE flag to toggle the verification.
+#
+# Example use:
+# @CODE
+# inherit verify-sig
+#
+# SRC_URI="https://example.org/${P}.tar.gz
+#   verify-sig? ( https://example.org/${P}.tar.gz.sig )"
+# BDEPEND="
+#   verify-sig? ( app-crypt/openpgp-keys-example )"
+#
+# VERIFY_SIG_OPENPGP_KEY_PATH=/usr/share/openpgp-keys/example.asc
+# @CODE
+
+case "${EAPI:-0}" in
+	0|1|2|3|4|5|6)
+		die "Unsupported EAPI=${EAPI} (obsolete) for ${ECLASS}"
+		;;
+	7)
+		;;
+	*)
+		die "Unsupported EAPI=${EAPI} (unknown) for ${ECLASS}"
+		;;
+esac
+
+EXPORT_FUNCTIONS src_unpack
+
+if [[ ! ${_VERIFY_SIG_ECLASS} ]]; then
+
+IUSE="verify-sig"
+
+BDEPEND="
+	verify-sig? (
+		app-crypt/gnupg
+		>=app-portage/gemato-16
+	)"
+
+# @ECLASS-VARIABLE: VERIFY_SIG_OPENPGP_KEY_PATH
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# Path to key bundle used to perform the verification.  This is required
+# when using default src_unpack.  Alternatively, the key path can be
+# passed directly to the verification functions.
+
+# @ECLASS-VARIABLE: VERIFY_SIG_OPENPGP_KEYSERVER
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# Keyserver used to refresh keys.  If not specified, the keyserver
+# preference from the key will be respected.  If no preference
+# is specified by the key, the GnuPG default will be used.
+
+# @ECLASS-VARIABLE: VERIFY_SIG_OPENPGP_KEY_REFRESH
+# @USER_VARIABLE
+# @DESCRIPTION:
+# Attempt to refresh keys via WKD/keyserver.  Set it to "yes"
+# in make.conf to enable.  Note that this requires working Internet
+# connection.
+: ${VERIFY_SIG_OPENPGP_KEY_REFRESH:=no}
+
+# @FUNCTION: verify-sig_verify_detached
+# @USAGE: <file> <sig-file> [<key-file>]
+# @DESCRIPTION:
+# Read the detached signature from <sig-file> and verify <file> against
+# it.  <key-file> can either be passed directly, or it defaults
+# to VERIFY_SIG_OPENPGP_KEY_PATH.  The function dies if verification
+# fails.
+verify-sig_verify_detached() {
+	local file=${1}
+	local sig=${2}
+	local key=${3:-${VERIFY_SIG_OPENPGP_KEY_PATH}}
+
+	[[ -n ${key} ]] ||
+		die "${FUNCNAME}: no key passed and VERIFY_SIG_OPENPGP_KEY_PATH unset"
+
+	local extra_args=()
+	[[ ${VERIFY_SIG_OPENPGP_KEY_REFRESH} == yes ]] || extra_args+=( -R )
+	[[ -n ${VERIFY_SIG_OPENPGP_KEYSERVER+1} ]] && extra_args+=(
+		--keyserver "${VERIFY_SIG_OPENPGP_KEYSERVER}"
+	)
+
+	# GPG upstream knows better than to follow the spec, so we can't
+	# override this directory.  However, there is a clean fallback
+	# to GNUPGHOME.
+	addpredict /run/user
+
+	local filename=${file##*/}
+	[[ ${file} == - ]] && filename='(stdin)'
+	einfo "Verifying ${filename} ..."
+	gemato gpg-wrap -K "${key}" "${extra_args[@]}" -- \
+		gpg --verify "${sig}" "${file}" ||
+		die "PGP signature verification failed"
+}
+
+# @FUNCTION: verify-sig_verify_message
+# @USAGE: <file> <output-file> [<key-file>]
+# @DESCRIPTION:
+# Verify that the file ('-' for stdin) contains a valid, signed PGP
+# message and write the message into <output-file> ('-' for stdout).
+# <key-file> can either be passed directly, or it defaults
+# to VERIFY_SIG_OPENPGP_KEY_PATH.  The function dies if verification
+# fails.  Note that using output from <output-file> is important as it
+# prevents the injection of unsigned data.
+verify-sig_verify_message() {
+	local file=${1}
+	local output_file=${2}
+	local key=${3:-${VERIFY_SIG_OPENPGP_KEY_PATH}}
+
+	[[ -n ${key} ]] ||
+		die "${FUNCNAME}: no key passed and VERIFY_SIG_OPENPGP_KEY_PATH unset"
+
+	local extra_args=()
+	[[ ${VERIFY_SIG_OPENPGP_KEY_REFRESH} == yes ]] || extra_args+=( -R )
+	[[ -n ${VERIFY_SIG_OPENPGP_KEYSERVER+1} ]] && extra_args+=(
+		--keyserver "${VERIFY_SIG_OPENPGP_KEYSERVER}"
+	)
+
+	# GPG upstream knows better than to follow the spec, so we can't
+	# override this directory.  However, there is a clean fallback
+	# to GNUPGHOME.
+	addpredict /run/user
+
+	local filename=${file##*/}
+	[[ ${file} == - ]] && filename='(stdin)'
+	einfo "Verifying ${filename} ..."
+	gemato gpg-wrap -K "${key}" "${extra_args[@]}" -- \
+		gpg --verify --output="${output_file}" "${file}" ||
+		die "PGP signature verification failed"
+}
+
+# @FUNCTION: verify-sig_verify_signed_checksums
+# @USAGE: <checksum-file> <algo> <files> [<key-file>]
+# @DESCRIPTION:
+# Verify the checksums for all files listed in the space-separated list
+# <files> (akin to ${A}) using a PGP-signed <checksum-file>.  <algo>
+# specified the checksum algorithm (e.g. sha256).  <key-file> can either
+# be passed directly, or it defaults to VERIFY_SIG_OPENPGP_KEY_PATH.
+#
+# The function dies if PGP verification fails, the checksum file
+# contains unsigned data, one of the files do not match checksums
+# or are missing from the checksum file.
+verify-sig_verify_signed_checksums() {
+	local checksum_file=${1}
+	local algo=${2}
+	local files=()
+	read -r -d '' -a files <<<"${3}"
+	local key=${4:-${VERIFY_SIG_OPENPGP_KEY_PATH}}
+
+	local chksum_prog chksum_len
+	case ${algo} in
+		sha256)
+			chksum_prog=sha256sum
+			chksum_len=64
+			;;
+		*)
+			die "${FUNCNAME}: unknown checksum algo ${algo}"
+			;;
+	esac
+
+	[[ -n ${key} ]] ||
+		die "${FUNCNAME}: no key passed and VERIFY_SIG_OPENPGP_KEY_PATH unset"
+
+	local checksum filename junk ret=0 count=0
+	while read -r checksum filename junk; do
+		[[ ${#checksum} -eq ${chksum_len} ]] || continue
+		[[ -z ${checksum//[0-9a-f]} ]] || continue
+		has "${filename}" "${files[@]}" || continue
+		[[ -z ${junk} ]] || continue
+
+		"${chksum_prog}" -c --strict - <<<"${checksum} ${filename}"
+		if [[ ${?} -eq 0 ]]; then
+			(( count++ ))
+		else
+			ret=1
+		fi
+	done < <(verify-sig_verify_message "${checksum_file}" - "${key}")
+
+	[[ ${ret} -eq 0 ]] ||
+		die "${FUNCNAME}: at least one file did not verify successfully"
+	[[ ${count} -eq ${#files[@]} ]] ||
+		die "${FUNCNAME}: checksums for some of the specified files were missing"
+}
+
+# @FUNCTION: verify-sig_src_unpack
+# @DESCRIPTION:
+# Default src_unpack override that verifies signatures for all
+# distfiles if 'verify-sig' flag is enabled.  The function dies if any
+# of the signatures fails to verify or if any distfiles are not signed.
+# Please write src_unpack() yourself if you need to perform partial
+# verification.
+verify-sig_src_unpack() {
+	if use verify-sig; then
+		local f suffix found
+		local distfiles=() signatures=() nosigfound=() straysigs=()
+
+		# find all distfiles and signatures, and combine them
+		for f in ${A}; do
+			found=
+			for suffix in .asc .sig; do
+				if [[ ${f} == *${suffix} ]]; then
+					signatures+=( "${f}" )
+					found=sig
+					break
+				else
+					if has "${f}${suffix}" ${A}; then
+						distfiles+=( "${f}" )
+						found=dist+sig
+						break
+					fi
+				fi
+			done
+			if [[ ! ${found} ]]; then
+				nosigfound+=( "${f}" )
+			fi
+		done
+
+		# check if all distfiles are signed
+		if [[ ${#nosigfound[@]} -gt 0 ]]; then
+			eerror "The following distfiles lack detached signatures:"
+			for f in "${nosigfound[@]}"; do
+				eerror "  ${f}"
+			done
+			die "Unsigned distfiles found"
+		fi
+
+		# check if there are no stray signatures
+		for f in "${signatures[@]}"; do
+			if ! has "${f%.*}" "${distfiles[@]}"; then
+				straysigs+=( "${f}" )
+			fi
+		done
+		if [[ ${#straysigs[@]} -gt 0 ]]; then
+			eerror "The following signatures do not match any distfiles:"
+			for f in "${straysigs[@]}"; do
+				eerror "  ${f}"
+			done
+			die "Unused signatures found"
+		fi
+
+		# now perform the verification
+		for f in "${signatures[@]}"; do
+			verify-sig_verify_detached \
+				"${DISTDIR}/${f%.*}" "${DISTDIR}/${f}"
+		done
+	fi
+
+	# finally, unpack the distfiles
+	default_src_unpack
+}
+
+_VERIFY_SIG_ECLASS=1
+fi