libzfs: add keylocation=https://, backed by fetch(3) or libcurl

Add support for http and https to the keylocation properly to
allow encryption keys to be fetched from the specified URL.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Issue #9543
Closes #9947
Closes #11956

contrib/dracut/90zfs/module-setup.sh.in

@@ -60,6 +60,11 @@ install() {
 		# Fallback: Guess the path and include all matches
 		dracut_install /usr/lib*/gcc/**/libgcc_s.so*
 	fi
+	if [ @LIBFETCH_DYNAMIC@ != 0 ]; then
+		for d in $libdirs; do
+			[ -e "$d"/@LIBFETCH_SONAME@ ] && dracut_install "$d"/@LIBFETCH_SONAME@
+		done
+	fi
 	dracut_install @mounthelperdir@/mount.zfs
 	dracut_install @udevdir@/vdev_id
 	dracut_install awk

contrib/dracut/90zfs/zfs-env-bootfs.service.in

@@ -8,7 +8,7 @@ Before=zfs-import.target
 
 [Service]
 Type=oneshot
-ExecStart=/bin/sh -c "systemctl set-environment BOOTFS=$(@sbindir@/zpool list -H -o bootfs | grep -m1 -v '^-$')"
+ExecStart=/bin/sh -c "exec systemctl set-environment BOOTFS=$(@sbindir@/zpool list -H -o bootfs | grep -m1 -v '^-$')"
 
 [Install]
 WantedBy=zfs-import.target

contrib/dracut/90zfs/zfs-load-key.sh.in

@@ -43,13 +43,14 @@ if [ "$(zpool list -H -o feature@encryption "${BOOTFS%%/*}")" = 'active' ]; then
 
         KEYLOCATION="$(zfs get -H -o value keylocation "${ENCRYPTIONROOT}")"
         if ! [ "${KEYLOCATION}" = "prompt" ]; then
+            if ! [ "${KEYLOCATION#http}" = "${KEYLOCATION}" ]; then
+                systemctl start network-online.target
+            fi
             zfs load-key "${ENCRYPTIONROOT}"
         else
             # decrypt them
-            TRY_COUNT=5
-            while [ $TRY_COUNT -gt 0 ]; do
+            for _ in 1 2 3 4 5; do
                 systemd-ask-password "Encrypted ZFS password for ${BOOTFS}" --no-tty | zfs load-key "${ENCRYPTIONROOT}" && break
-                TRY_COUNT=$((TRY_COUNT - 1))
             done
         fi
     fi

contrib/dracut/90zfs/zfs-rollback-bootfs.service.in

@@ -10,5 +10,5 @@ ConditionKernelCommandLine=bootfs.rollback
 # ${BOOTFS} should have been set by zfs-env-bootfs.service
 Type=oneshot
 ExecStartPre=/bin/sh -c 'test -n "${BOOTFS}"'
-ExecStart=/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.rollback)"; @sbindir@/zfs rollback -Rf "${BOOTFS}@${SNAPNAME:-%v}"'
+ExecStart=/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.rollback)"; exec @sbindir@/zfs rollback -Rf "${BOOTFS}@${SNAPNAME:-%v}"'
 RemainAfterExit=yes

contrib/dracut/90zfs/zfs-snapshot-bootfs.service.in

@@ -10,5 +10,5 @@ ConditionKernelCommandLine=bootfs.snapshot
 # ${BOOTFS} should have been set by zfs-env-bootfs.service
 Type=oneshot
 ExecStartPre=/bin/sh -c 'test -n "${BOOTFS}"'
-ExecStart=-/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.snapshot)"; @sbindir@/zfs snapshot "${BOOTFS}@${SNAPNAME:-%v}"'
+ExecStart=-/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.snapshot)"; exec @sbindir@/zfs snapshot "${BOOTFS}@${SNAPNAME:-%v}"'
 RemainAfterExit=yes

contrib/initramfs/hooks/zfs.in

@@ -30,6 +30,13 @@ find /lib/ -type f -name "libgcc_s.so.[1-9]" | while read -r libgcc; do
 	copy_exec "$libgcc"
 done
 
+# shellcheck disable=SC2050
+if [ @LIBFETCH_DYNAMIC@ != 0 ]; then
+	find /lib/ -name @LIBFETCH_SONAME@ | while read -r libfetch; do
+		copy_exec "$libfetch"
+	done
+fi
+
 copy_file config "/etc/hostid"
 copy_file cache  "@sysconfdir@/zfs/zpool.cache"
 copy_file config "@initconfdir@/zfs"

contrib/initramfs/scripts/zfs

@@ -403,28 +403,25 @@ decrypt_fs()
 			KEYSTATUS="$(get_fs_value "${ENCRYPTIONROOT}" keystatus)"
 			# Continue only if the key needs to be loaded
 			[ "$KEYSTATUS" = "unavailable" ] || return 0
-			TRY_COUNT=3
 
-			# If key is stored in a file, do not prompt
+			# Do not prompt if key is stored noninteractively,
 			if ! [ "${KEYLOCATION}" = "prompt" ]; then
 				$ZFS load-key "${ENCRYPTIONROOT}"
 
 			# Prompt with plymouth, if active
-			elif [ -e /bin/plymouth ] && /bin/plymouth --ping 2>/dev/null; then
+			elif /bin/plymouth --ping 2>/dev/null; then
 				echo "plymouth" > /run/zfs_console_askpwd_cmd
-				while [ $TRY_COUNT -gt 0 ]; do
+				for _ in 1 2 3; do
 					plymouth ask-for-password --prompt "Encrypted ZFS password for ${ENCRYPTIONROOT}" | \
 						$ZFS load-key "${ENCRYPTIONROOT}" && break
-					TRY_COUNT=$((TRY_COUNT - 1))
 				done
 
 			# Prompt with systemd, if active
 			elif [ -e /run/systemd/system ]; then
 				echo "systemd-ask-password" > /run/zfs_console_askpwd_cmd
-				while [ $TRY_COUNT -gt 0 ]; do
+				for _ in 1 2 3; do
 					systemd-ask-password "Encrypted ZFS password for ${ENCRYPTIONROOT}" --no-tty | \
 						$ZFS load-key "${ENCRYPTIONROOT}" && break
-					TRY_COUNT=$((TRY_COUNT - 1))
 				done
 
 			# Prompt with ZFS tty, otherwise