diff options
authorEd Maste <emaste@FreeBSD.org>2021-10-07 03:31:17 +0000
committerEd Maste <emaste@FreeBSD.org>2021-11-04 17:01:44 +0000
commite9a994639b2af232f994ba2ad23ca45a17718d2b (patch)
parent305ef653bcf349c7dea83c90add6f2d97910e545 (diff)
ssh: enable FIDO/U2F keys
Description of FIDO/U2F support (from OpenSSH 8.2 release notes, https://www.openssh.com/txt/release-8.2): This release adds support for FIDO/U2F hardware authenticators to OpenSSH. U2F/FIDO are open standards for inexpensive two-factor authentication hardware that are widely used for website authentication. In OpenSSH FIDO devices are supported by new public key types "ecdsa-sk" and "ed25519-sk", along with corresponding certificate types. ssh-keygen(1) may be used to generate a FIDO token-backed key, after which they may be used much like any other key type supported by OpenSSH, so long as the hardware token is attached when the keys are used. FIDO tokens also generally require the user explicitly authorise operations by touching or tapping them. Generating a FIDO key requires the token be attached, and will usually require the user tap the token to confirm the operation: $ ssh-keygen -t ecdsa-sk -f ~/.ssh/id_ecdsa_sk Generating public/private ecdsa-sk key pair. You may need to touch your security key to authorize key generation. Enter file in which to save the key (/home/djm/.ssh/id_ecdsa_sk): Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/djm/.ssh/id_ecdsa_sk Your public key has been saved in /home/djm/.ssh/id_ecdsa_sk.pub This will yield a public and private key-pair. The private key file should be useless to an attacker who does not have access to the physical token. After generation, this key may be used like any other supported key in OpenSSH and may be listed in authorized_keys, added to ssh-agent(1), etc. The only additional stipulation is that the FIDO token that the key belongs to must be attached when the key is used. To enable FIDO/U2F support, this change regenerates ssh_namespace.h, adds ssh-sk-helper, and sets ENABLE_SK_INTERNAL (unless building WITHOUT_USB). devd integration is not included in this change, and is under investigation for the base system. In the interim the security/u2f-devd port can be installed to provide appropriate devd rules. Reviewed by: delphij, kevans Relnotes: Yes Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D32509
5 files changed, 37 insertions, 1 deletions
diff --git a/crypto/openssh/ssh_namespace.h b/crypto/openssh/ssh_namespace.h
index 2c2060567460..94a391ee5f45 100644
--- a/crypto/openssh/ssh_namespace.h
+++ b/crypto/openssh/ssh_namespace.h
@@ -87,6 +87,10 @@
#define chacha_encrypt_bytes Fssh_chacha_encrypt_bytes
#define chacha_ivsetup Fssh_chacha_ivsetup
#define chacha_keysetup Fssh_chacha_keysetup
+#define chachapoly_crypt Fssh_chachapoly_crypt
+#define chachapoly_free Fssh_chachapoly_free
+#define chachapoly_get_length Fssh_chachapoly_get_length
+#define chachapoly_new Fssh_chachapoly_new
#define chan_ibuf_empty Fssh_chan_ibuf_empty
#define chan_is_dead Fssh_chan_is_dead
#define chan_mark_dead Fssh_chan_mark_dead
@@ -553,8 +557,10 @@
#define ssh_dss_sign Fssh_ssh_dss_sign
#define ssh_dss_verify Fssh_ssh_dss_verify
#define ssh_ecdsa_sign Fssh_ssh_ecdsa_sign
+#define ssh_ecdsa_sk_verify Fssh_ssh_ecdsa_sk_verify
#define ssh_ecdsa_verify Fssh_ssh_ecdsa_verify
#define ssh_ed25519_sign Fssh_ssh_ed25519_sign
+#define ssh_ed25519_sk_verify Fssh_ssh_ed25519_sk_verify
#define ssh_ed25519_verify Fssh_ssh_ed25519_verify
#define ssh_err Fssh_ssh_err
#define ssh_fetch_identitylist Fssh_ssh_fetch_identitylist
@@ -871,6 +877,12 @@
#define sshpkt_start Fssh_sshpkt_start
#define sshpkt_vfatal Fssh_sshpkt_vfatal
#define sshsigdie Fssh_sshsigdie
+#define sshsk_add_option Fssh_sshsk_add_option
+#define sshsk_enroll Fssh_sshsk_enroll
+#define sshsk_key_from_response Fssh_sshsk_key_from_response
+#define sshsk_load_resident Fssh_sshsk_load_resident
+#define sshsk_open Fssh_sshsk_open
+#define sshsk_sign Fssh_sshsk_sign
#define start_progress_meter Fssh_start_progress_meter
#define stdfd_devnull Fssh_stdfd_devnull
#define stop_progress_meter Fssh_stop_progress_meter
diff --git a/secure/libexec/Makefile b/secure/libexec/Makefile
index 3438b412d5da..f07454db3643 100644
--- a/secure/libexec/Makefile
+++ b/secure/libexec/Makefile
@@ -4,7 +4,7 @@
.if ${MK_OPENSSH} != "no"
-SUBDIR+=sftp-server ssh-keysign ssh-pkcs11-helper
+SUBDIR+=sftp-server ssh-keysign ssh-pkcs11-helper ssh-sk-helper
SUBDIR.${MK_TESTS}+= tests
diff --git a/secure/libexec/ssh-sk-helper/Makefile b/secure/libexec/ssh-sk-helper/Makefile
new file mode 100644
index 000000000000..622b0ac682bd
--- /dev/null
+++ b/secure/libexec/ssh-sk-helper/Makefile
@@ -0,0 +1,16 @@
+.include <src.opts.mk>
+.include "${SRCTOP}/secure/ssh.mk"
+PROG= ssh-sk-helper
+SRCS= ssh-sk-helper.c ssh-sk.c sk-usbhid.c
+MAN= ssh-sk-helper.8
+LIBADD= ssh crypto z
+.if ${MK_USB} != "no"
+LIBADD+= fido2 cbor
+.include <bsd.prog.mk>
diff --git a/secure/ssh.mk b/secure/ssh.mk
index 4ab8cd399ae8..822946253263 100644
--- a/secure/ssh.mk
+++ b/secure/ssh.mk
@@ -1,6 +1,12 @@
# Common Make variables for OpenSSH
+.include <src.opts.mk>
SSHDIR= ${SRCTOP}/crypto/openssh
CFLAGS+= -I${SSHDIR} -include ssh_namespace.h
SRCS+= ssh_namespace.h
+.if ${MK_USB} != "no"
diff --git a/tools/build/mk/OptionalObsoleteFiles.inc b/tools/build/mk/OptionalObsoleteFiles.inc
index 91822aac492a..96156a80f2e3 100644
--- a/tools/build/mk/OptionalObsoleteFiles.inc
+++ b/tools/build/mk/OptionalObsoleteFiles.inc
@@ -7141,6 +7141,7 @@ OLD_FILES+=usr/lib32/libprivatessh_p.a
@@ -7157,6 +7158,7 @@ OLD_FILES+=usr/share/man/man8/pam_ssh.8.gz