From bbc31b8303d34053562c9cb6e2c1132f124bfdb1 Mon Sep 17 00:00:00 2001
From: Alexander Scheel <ascheel@redhat.com>
Date: Wed, 16 Jan 2019 17:16:09 -0500
Subject: [PATCH 1/2] Add validate-then-import certificate utility
The NSS utility certutil requires certificates to be imported
(`certutil -A`) prior to validating their signatures and usage
(`certutil -V -e`). PKICertImport avoids this pitfall by handling both
import and validation in the same step, so if the validation fails, the
certificate is removed. This ensures it is not accidentally used before
it is verified.
Signed-off-by: Alexander Scheel <ascheel@redhat.com>
(cherry picked from commit a187cccc269968e310d97eafc99771d2cd5b366e)
---
base/util/PKICertImport.bash | 328 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 328 insertions(+)
create mode 100755 base/util/PKICertImport.bash
diff --git a/base/util/PKICertImport.bash b/base/util/PKICertImport.bash
new file mode 100755
index 0000000..d0b54c7
--- /dev/null
+++ b/base/util/PKICertImport.bash
@@ -0,0 +1,328 @@
+#!/bin/bash
+
+# Copyright (C) 2018 Red Hat
+
+# PKICertImport performs a validate-then-import strategy for importing
+# certificates into a NSS DB or HSM Token by wrapping both calls to
+# certutil (`certutil -A` and `certutil -V`) such that the certificate
+# will be removed if import fails (`certutil -D`). This helps to ensure
+# that certificates are not used prior to validation.
+function PKICertImport() {
+ ## [ overview ] ##
+
+ # This script has four major sections:
+ #
+ # 1. Globals -- the definitions of all script-global variables
+ # 2. Helper functions -- functions which don't perform key operations
+ # 3. Core commands -- functions which interact with the NSS DB via
+ # certutil
+ # 4. Program flow -- main flow of the program
+
+
+ ## [ globals ] ##
+
+ # Path to certificate; parsed from arguments.
+ local CERT_PATH=""
+
+ # User-given nickname for the certificate.
+ local CERT_NICKNAME=""
+
+ # Whether or not the certificate is in ASCII/PEM format.
+ local CERT_ASCII="false"
+
+ # What trust flags to use when importing the certificate.
+ local CERT_TRUST=""
+
+ # What usage flags to validate the certificate against.
+ local CERT_USAGE=""
+
+ # Location of the original NSS DB.
+ local NSSDB=""
+
+ # Type of the NSSDB.
+ local NSSDB_TYPE=""
+
+ # Location to the NSS DB Password file, if present.
+ local NSSDB_PASSWORD=""
+
+ # Name of the HSM token, if used.
+ local HSM_TOKEN=""
+
+
+ ## [ helper functions ] ##
+
+ # __e prints error messages, prefixing them with "e: " and writing the
+ # output to stderr instead of stdout.
+ function __e() {
+ echo "e:" "$@" 1>&2
+ }
+
+ # __v prints debug messages in verbose mode; these also go to stderr.
+ # Messages are only present if the environment variable VERBOSE is set.
+ function __v() {
+ if [ "x$VERBOSE" != "x" ]; then
+ echo "v:" "$@" 1>&2
+ fi
+ }
+
+ ## [ core commands ] ##
+
+ # Parse the command line arguments and set the appropriate global
+ # variables. Return status of non-zero indicates a fatal error; help
+ # should be displayed. Return status of zero indicates no error and help
+ # should not be displayed.
+ function _parse_args() {
+ # Use a read-and-shift approach to parse both "<option>" and
+ # "<option> <value>" forms.
+ while (( $# > 0 )); do
+ local arg="$1"
+ shift
+
+ # Sorted alphabetically by short option.
+ if [ "x$arg" == "x--ascii" ] || [ "x$arg" == "x-a" ]; then
+ # If specified, the -a flag is passed when the certificate is
+ # imported.
+ CERT_ASCII="true"
+ elif [ "x$arg" == "x--database" ] || [ "x$arg" == "x-d" ]; then
+ # Always required; path to the original NSS DB. Note that this
+ # differs from certutil in that we detect the NSSDB type here,
+ # versus taking a prefix:path combination.
+ NSSDB="$1"
+
+ if [ -e "$NSSDB/cert8.db" ] && [ ! -e "$NSSDB/cert9.db" ]; then
+ NSSDB_TYPE="dbm:"
+ elif [ ! -e "$NSSDB/cert8.db" ] && [ -e "$NSSDB/cert9.db" ]; then
+ NSSDB_TYPE="sql:"
+ else
+ __e "Unknown NSS DB type for directory: $NSSDB"
+ __e "Please ensure only one of cert8.db or cert9.db exist"
+ return 1
+ fi
+
+ shift
+ elif [ "x$arg" == "x--password" ] || [ "x$arg" == "x-f" ]; then
+ # If specified, path to a file containing the NSS DB password.
+ NSSDB_PASSWORD="$1"
+ shift
+ elif [ "x$arg" == "x--hsm" ] || [ "x$arg" == "x-h" ]; then
+ # If specified, name of the HSM Token.
+ HSM_TOKEN="$1"
+ shift
+ elif [ "x$arg" == "x--certificate" ] || [ "x$arg" == "x-i" ]; then
+ # Always required; path to the original certificate.
+ CERT_PATH="$1"
+ shift
+ elif [ "x$arg" == "x--nickname" ] || [ "x$arg" == "x-n" ]; then
+ # Always required; nickname for the certificate.
+ CERT_NICKNAME="$1"
+ shift
+ elif [ "x$arg" == "x--trust" ] || [ "x$arg" == "x-t" ]; then
+ # Always required; certificate trust flags.
+ CERT_TRUST="$1"
+ shift
+ elif [ "x$arg" == "x--usage" ] || [ "x$arg" == "x-u" ]; then
+ # Always required; certificate usage flags.
+ CERT_USAGE="$1"
+ shift
+ else
+ # We print help whenever the return code is 1, so we don't
+ # need to explicitly parse a --help flag, but we will get
+ # an extraneous but harmless unknown argument message.
+ __e "Unknown argument: $arg"
+ __e "Check your option syntax; perhaps a prior argument is" \
+ "missing a value?"
+ return 1
+ fi
+ done
+
+ # Ensure that we've seen the required arguments.
+ if [ "x$NSSDB" == "x" ]; then
+ __e "Missing NSS Database location: specify --database/-d"
+ return 1
+ elif [ "x$CERT_PATH" == "x" ]; then
+ __e "Missing certificate location: specify --certificate/-i"
+ return 1
+ elif [ "x$CERT_NICKNAME" == "x" ]; then
+ __e "Missing certificate nickname: specify --nickname/-n"
+ return 1
+ elif [ "x$CERT_TRUST" == "x" ]; then
+ __e "Missing certificate trust: specify --trust/-t"
+ return 1
+ elif [ "x$CERT_USAGE" == "x" ]; then
+ __e "Missing certificate usage: specify --usage/-u"
+ return 1
+ fi
+
+ # All good to go.
+ return 0
+ }
+
+ # Show help and usage information.
+ function _print_help() {
+ if (( $1 != 0 )); then
+ echo ""
+ fi
+
+ echo "Usage: $0 [arguments]"
+ echo "$0 validates and imports certificates."
+ echo ""
+ echo "Requred arguments:"
+ echo "--database, -d <path>: path to the NSS DB"
+ echo "--certificate, -i <path>: path to the certificate to import"
+ echo "--nickname, -n <name>: nickname for the certificate"
+ echo "--trust, -t <flags>: trust flags for the certificate"
+ echo "--usage, -u <flag>: usage flag to verify the certificate with"
+ echo ""
+ echo "Optional arguments:"
+ echo "--ascii, -a: the certificate is in ASCII encoded"
+ echo "--password, -f <path>: password file for the NSS DB"
+ echo "--hsm, -h <name>: name of the HSM to use"
+ echo ""
+ echo "Environment variables:"
+ echo "VERBOSE: see certutil commands being run"
+ echo ""
+ echo "For more information about these options, refer to the" \
+ "certutil documentation."
+ }
+
+ # Import a certificate into the NSS DB specified on $1. Errors are fatal;
+ # uses exit instead of return.
+ function _import_cert() {
+ local database="$1"
+ local ret=0
+ local add_args=("-A")
+
+ # Use a single import command, setting trust as we import.
+ add_args+=("-d" "$NSSDB_TYPE$database")
+ add_args+=("-n" "$CERT_NICKNAME")
+ if [ "x$NSSDB_PASSWORD" != "x" ]; then
+ add_args+=("-f" "$NSSDB_PASSWORD")
+ fi
+ add_args+=("-i" "$CERT_PATH")
+ if [ "$CERT_ASCII" == "true" ]; then
+ add_args+=("-a")
+ fi
+ if [ "x$HSM_TOKEN" != "x" ]; then
+ add_args+=("-h" "$HSM_TOKEN")
+ fi
+ add_args+=("-t" "$CERT_TRUST")
+
+ # Import the certificate...
+ __v certutil "${add_args[@]}"
+ certutil "${add_args[@]}"
+ ret=$?
+ if (( ret != 0 )); then
+ __e "certutil returned non-zero value: $ret"
+ __e "Unable to import certificate to NSS DB: $NSSDB."
+ exit $ret
+ fi
+ }
+
+ # Verify the certificate in the NSS DB specified by $1.
+ function _verify_cert() {
+ local database="$1"
+ local ret=0
+ local verify_args=("-V")
+
+ verify_args+=("-d" "$NSSDB_TYPE$database")
+ verify_args+=("-n" "$CERT_NICKNAME")
+ verify_args+=("-u" "$CERT_USAGE")
+ if [ "x$HSM_TOKEN" != "x" ]; then
+ verify_args+=("-h" "$HSM_TOKEN")
+ fi
+ if [ "x$NSSDB_PASSWORD" != "x" ]; then
+ verify_args+=("-f" "$NSSDB_PASSWORD")
+ fi
+
+ # Ensures that the signature is checked as well.
+ verify_args+=("-e")
+
+ # Validate the certificate. Note that we have to pattern match on the
+ # output of certutil -V; the return code is uncorrelated with the
+ # actual result. (It is dependent upon whether or not a HSM is used).
+ __v certutil "${verify_args[@]}"
+
+ local certutil_result=""
+ certutil_result="$(certutil "${verify_args[@]}" 2>&1)"
+
+ grep -q '^certutil: certificate is valid$' <<< "$certutil_result"
+ ret=$?
+
+ if (( ret != 0 )); then
+ __e "$certutil_result" 1>&2
+ fi
+
+ return $ret
+ }
+
+ # Remove the certificate from the NSS DB specified by $1. Errors are fatal;
+ # uses exit instead of return.
+ function _remove_cert() {
+ local database="$1"
+ local remove_args=("-D")
+
+ remove_args+=("-d" "$NSSDB_TYPE$database")
+ if [ "x$NSSDB_PASSWORD" != "x" ]; then
+ remove_args+=("-f" "$NSSDB_PASSWORD")
+ fi
+
+ __v certutil "${remove_args[@]}" "-n" "$CERT_NICKNAME"
+ certutil "${remove_args[@]}" "-n" "$CERT_NICKNAME"
+ local ret=$?
+ if (( ret != 0 )); then
+ __e "certutil returned non-zero result: $ret"
+ __e "Unable to delete certificate!"
+ exit $?
+ fi
+
+ if [ "x$HSM_TOKEN" != "x" ]; then
+ # In the event we have a HSM, we also have to remove it from the
+ # HSM token.
+
+ __v certutil "${remove_args[@]}" "-n" "$HSM_TOKEN:$CERT_NICKNAME"
+ certutil "${remove_args[@]}" "-n" "$HSM_TOKEN:$CERT_NICKNAME"
+ local ret=$?
+ if (( ret != 0 )); then
+ __e "certutil returned non-zero result: $ret"
+ __e "Unable to delete certificate!"
+ exit $?
+ fi
+ fi
+ }
+
+ ## [ program flow ] ##
+ local ret=0
+
+ # The program flow of this script is:
+ #
+ # - Parse arguments
+ # - [print help if required]
+ # - Create working directory
+ # - Copy files into the working directory
+ # - Import certificate into NSS DB
+ # - Validate certificate in NSS DB
+ # - [on failure, remove from NSS DB]
+ #
+ # Import is handled by _import_cert, verification is handled by
+ # _verify_cert, and removal is handled by _remove_cert.
+
+ _parse_args "$@"
+ ret="$?"
+ if (( ret != 0 )); then
+ _print_help $ret
+ exit 1
+ fi
+
+ _import_cert "$NSSDB"
+ _verify_cert "$NSSDB"
+ ret=$?
+
+ # Check if the verification failed. If it did, remove it from the NSS DB.
+ if (( ret != 0 )); then
+ __e "Verification of certificate failed!"
+ _remove_cert "$NSSDB"
+ exit 1
+ fi
+}
+
+PKICertImport "$@"
--
1.8.3.1
From af5461c22cda63a41c9f27df6d119db11bb55f8d Mon Sep 17 00:00:00 2001
From: Alexander Scheel <ascheel@redhat.com>
Date: Thu, 24 Jan 2019 16:28:42 -0500
Subject: [PATCH 2/2] Add PKICertImport to pki
Signed-off-by: Alexander Scheel <ascheel@redhat.com>
("cherry picked from commit b85472cd6c33828c5d9bd7248291515687b5ca1f"
with manual changes)
---
base/util/CMakeLists.txt | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/base/util/CMakeLists.txt b/base/util/CMakeLists.txt
index 94e30cc..98dac91 100644
--- a/base/util/CMakeLists.txt
+++ b/base/util/CMakeLists.txt
@@ -2,3 +2,9 @@ project(util NONE)
add_subdirectory(src)
add_subdirectory(test)
+
+install(FILES PKICertImport.bash
+ DESTINATION ${BIN_INSTALL_DIR}
+ RENAME PKICertImport
+ PERMISSIONS OWNER_EXECUTE OWNER_WRITE OWNER_READ
+ GROUP_EXECUTE GROUP_READ)
--
1.8.3.1