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-rw-r--r--meta/recipes-extended/mc/files/CVE-2021-36370.patch609
1 files changed, 609 insertions, 0 deletions
diff --git a/meta/recipes-extended/mc/files/CVE-2021-36370.patch b/meta/recipes-extended/mc/files/CVE-2021-36370.patch
new file mode 100644
index 0000000000..d6a26871bd
--- /dev/null
+++ b/meta/recipes-extended/mc/files/CVE-2021-36370.patch
@@ -0,0 +1,609 @@
+Backport patch to fix CVE-2021-36370.
+
+Upstream-Status: Backport [https://github.com/MidnightCommander/mc/commit/9235d3c]
+CVE: CVE-2021-36370
+
+Signed-off-by: Kai Kang <kai.kang@windriver.com>
+
+From 9235d3c232d13ad7f973346077c9cf2eaa77dc5f Mon Sep 17 00:00:00 2001
+From: Andrew Borodin <aborodin@vmail.ru>
+Date: Mon, 12 Jul 2021 08:48:18 +0300
+Subject: [PATCH] SFTPFS: verify server fingerprint (fix CVE-2021-36370).
+
+Use ~/.ssh/known_hosts file to verify server fingerprint
+using ssh way:
+
+$ ssh localhost
+The authenticity of host 'localhost (127.0.0.1)' can't be established.
+ED25519 key fingerprint is SHA256:FzqKTNTroFuNUj1wUzSeV2x/1lpcESnT0ZRCmq5H6o8.
+Are you sure you want to continue connecting (yes/no)? no
+ssh: Host key verification failed.
+
+$ ssh localhost
+The authenticity of host 'localhost (127.0.0.1)' can't be established.
+ED25519 key fingerprint is SHA256:FzqKTNTroFuNUj1wUzSeV2x/1lpcESnT0ZRCmq5H6o8.
+Are you sure you want to continue connecting (yes/no)? yes
+Warning: Permanently added 'localhost' (ED25519) to the list of known hosts.
+andrew@localhost's password:
+
+Thanks the Curl project for the used code.
+
+Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
+Signed-off-by: Yury V. Zaytsev <yury.zaytsev@moneymeets.com>
+---
+ doc/man/mc.1.in | 15 ++
+ doc/man/ru/mc.1.in | 14 ++
+ src/vfs/sftpfs/connection.c | 428 +++++++++++++++++++++++++++++++++++-
+ src/vfs/sftpfs/internal.h | 5 +-
+ 4 files changed, 452 insertions(+), 10 deletions(-)
+
+diff --git a/doc/man/mc.1.in b/doc/man/mc.1.in
+index c0c06e32f7..7a3d118384 100644
+--- a/doc/man/mc.1.in
++++ b/doc/man/mc.1.in
+@@ -3364,6 +3364,21 @@ Examples:
+ sftp://joe@noncompressed.ssh.edu/private
+ sftp://joe@somehost.ssh.edu:2222/private
+ .fi
++.PP
++When establishing the connection, server key fingerprint is verified using
++the ~/.ssh/known_hosts file. If the host/key pair is not found or the host is found,
++but the key doesn't match, an appropriate message is shown.
++There are three buttons in the message dialog:
++.PP
++.B [Yes]
++add new host/key pair to the ~/.ssh/known_hosts file and continue.
++.PP
++.B [Ignore]
++do not add new host/key pair to the ~/.ssh/known_hosts file, but continue
++nevertheless (at you own risk).
++.PP
++.B [No]
++abort connection.
+ .\"NODE " Undelete File System"
+ .SH " Undelete File System"
+ On Linux systems, if you asked configure to use the ext2fs undelete
+diff --git a/doc/man/ru/mc.1.in b/doc/man/ru/mc.1.in
+index 7609da1127..bc0c1810a9 100644
+--- a/doc/man/ru/mc.1.in
++++ b/doc/man/ru/mc.1.in
+@@ -3874,6 +3874,20 @@ bash\-совместимая оболочка shell.
+ sftp://joe@noncompressed.ssh.edu/private
+ sftp://joe@somehost.ssh.edu:2222/private
+ .fi
++При установлении соединения происходит проверка ключа сервера с использованием
++файла ~/.ssh/known_hosts file. Если пара сервер/ключ в этом файле не найдена
++или сервер найден, но ключ не соответствует, пользователю показывается
++окно с соответствующим сообщением, содержащее три кнопки:
++.PP
++.B [Да]
++добавить новую пару сервер/ключ в файл ~/.ssh/known_hosts и продолжить соединение.
++.PP
++.B [Игнорировать]
++не добавлять новую пару сервер/ключ в файл ~/.ssh/known_hosts и всё равно
++продолжить соединение (на свой страх и риск).
++.PP
++.B [Нет]
++прервать соединение.
+ .\"NODE " Undelete File System"
+ .SH " Файловая система UFS (Undelete File System)"
+ В ОС Linux можно сконфигурировать файловую систему ext2fs, используемую
+diff --git a/src/vfs/sftpfs/connection.c b/src/vfs/sftpfs/connection.c
+index 9f8ea5633b..acd5026515 100644
+--- a/src/vfs/sftpfs/connection.c
++++ b/src/vfs/sftpfs/connection.c
+@@ -42,6 +42,8 @@
+ #include "lib/util.h"
+ #include "lib/tty/tty.h" /* tty_enable_interrupt_key () */
+ #include "lib/vfs/utilvfs.h"
++#include "lib/mcconfig.h" /* mc_config_get_home_dir () */
++#include "lib/widget.h" /* query_dialog () */
+
+ #include "internal.h"
+
+@@ -49,10 +51,37 @@
+
+ /*** file scope macro definitions ****************************************************************/
+
++#define SHA1_DIGEST_LENGTH 20
++
+ /*** file scope type declarations ****************************************************************/
+
+ /*** file scope variables ************************************************************************/
+
++#ifdef LIBSSH2_KNOWNHOST_KEY_ED25519
++static const char *const hostkey_method_ssh_ed25519 = "ssh-ed25519";
++#endif
++#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_521
++static const char *const hostkey_method_ssh_ecdsa_521 = "ecdsa-sha2-nistp521";
++#endif
++#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_384
++static const char *const hostkey_method_ssh_ecdsa_384 = "ecdsa-sha2-nistp384";
++#endif
++#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_256
++static const char *const hostkey_method_ssh_ecdsa_256 = "ecdsa-sha2-nistp256";
++#endif
++static const char *const hostkey_method_ssh_rsa = "ssh-rsa";
++static const char *const hostkey_method_ssh_dss = "ssh-dss";
++
++/**
++ *
++ * The current implementation of know host key checking has following limitations:
++ *
++ * - Only plain-text entries are supported (`HashKnownHosts no` OpenSSH option)
++ * - Only HEX-encoded SHA1 fingerprint display is supported (`FingerprintHash` OpenSSH option)
++ * - Resolved IP addresses are *not* saved/validated along with the hostnames
++ *
++ */
++
+ static const char *kbi_passwd = NULL;
+ static const struct vfs_s_super *kbi_super = NULL;
+
+@@ -70,9 +99,12 @@ static const struct vfs_s_super *kbi_super = NULL;
+ static int
+ sftpfs_open_socket (struct vfs_s_super *super, GError ** mcerror)
+ {
++ sftpfs_super_t *sftpfs_super = SFTP_SUPER (super);
+ struct addrinfo hints, *res = NULL, *curr_res;
+ int my_socket = 0;
+ char port[BUF_TINY];
++ static char address_ipv4[INET_ADDRSTRLEN];
++ static char address_ipv6[INET6_ADDRSTRLEN];
+ int e;
+
+ mc_return_val_if_error (mcerror, LIBSSH2_INVALID_SOCKET);
+@@ -120,6 +152,30 @@ sftpfs_open_socket (struct vfs_s_super *super, GError ** mcerror)
+ {
+ int save_errno;
+
++ switch (curr_res->ai_addr->sa_family)
++ {
++ case AF_INET:
++ sftpfs_super->ip_address =
++ inet_ntop (AF_INET, &((struct sockaddr_in *) curr_res->ai_addr)->sin_addr,
++ address_ipv4, INET_ADDRSTRLEN);
++ break;
++ case AF_INET6:
++ sftpfs_super->ip_address =
++ inet_ntop (AF_INET6, &((struct sockaddr_in6 *) curr_res->ai_addr)->sin6_addr,
++ address_ipv6, INET6_ADDRSTRLEN);
++ break;
++ default:
++ sftpfs_super->ip_address = NULL;
++ }
++
++ if (sftpfs_super->ip_address == NULL)
++ {
++ mc_propagate_error (mcerror, 0, "%s",
++ _("sftp: failed to convert remote host IP address into text form"));
++ my_socket = LIBSSH2_INVALID_SOCKET;
++ goto ret;
++ }
++
+ my_socket = socket (curr_res->ai_family, curr_res->ai_socktype, curr_res->ai_protocol);
+
+ if (my_socket < 0)
+@@ -161,8 +217,358 @@ sftpfs_open_socket (struct vfs_s_super *super, GError ** mcerror)
+ }
+
+ /* --------------------------------------------------------------------------------------------- */
++
++/**
++ * Read ~/.ssh/known_hosts file.
++ *
++ * @param super connection data
++ * @param mcerror pointer to the error handler
++ * @return TRUE on success, FALSE otherwise
++ *
++ * Thanks the Curl project for the code used in this function.
++ */
++static gboolean
++sftpfs_read_known_hosts (struct vfs_s_super *super, GError ** mcerror)
++{
++ sftpfs_super_t *sftpfs_super = SFTP_SUPER (super);
++ struct libssh2_knownhost *store = NULL;
++ int rc;
++ gboolean found = FALSE;
++
++ sftpfs_super->known_hosts = libssh2_knownhost_init (sftpfs_super->session);
++ if (sftpfs_super->known_hosts == NULL)
++ goto err;
++
++ sftpfs_super->known_hosts_file =
++ mc_build_filename (mc_config_get_home_dir (), ".ssh", "known_hosts", (char *) NULL);
++ rc = libssh2_knownhost_readfile (sftpfs_super->known_hosts, sftpfs_super->known_hosts_file,
++ LIBSSH2_KNOWNHOST_FILE_OPENSSH);
++ if (rc > 0)
++ {
++ const char *kh_name_end = NULL;
++
++ while (!found && libssh2_knownhost_get (sftpfs_super->known_hosts, &store, store) == 0)
++ {
++ /* For non-standard ports, the name will be enclosed in
++ * square brackets, followed by a colon and the port */
++ if (store == NULL)
++ continue;
++
++ if (store->name == NULL)
++ found = TRUE;
++ else if (store->name[0] != '[')
++ found = strcmp (store->name, super->path_element->host) == 0;
++ else
++ {
++ int port;
++
++ kh_name_end = strstr (store->name, "]:");
++ if (kh_name_end == NULL)
++ /* Invalid host pattern */
++ continue;
++
++ port = (int) g_ascii_strtoll (kh_name_end + 2, NULL, 10);
++ if (port == super->path_element->port)
++ {
++ size_t kh_name_size;
++
++ kh_name_size = strlen (store->name) - 1 - strlen (kh_name_end);
++ found = strncmp (store->name + 1, super->path_element->host, kh_name_size) == 0;
++ }
++ }
++ }
++ }
++
++ if (found)
++ {
++ int mask;
++ const char *hostkey_method = NULL;
++
++ mask = store->typemask & LIBSSH2_KNOWNHOST_KEY_MASK;
++
++ switch (mask)
++ {
++#ifdef LIBSSH2_KNOWNHOST_KEY_ED25519
++ case LIBSSH2_KNOWNHOST_KEY_ED25519:
++ hostkey_method = hostkey_method_ssh_ed25519;
++ break;
++#endif
++#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_521
++ case LIBSSH2_KNOWNHOST_KEY_ECDSA_521:
++ hostkey_method = hostkey_method_ssh_ecdsa_521;
++ break;
++#endif
++#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_384
++ case LIBSSH2_KNOWNHOST_KEY_ECDSA_384:
++ hostkey_method = hostkey_method_ssh_ecdsa_384;
++ break;
++#endif
++#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_256
++ case LIBSSH2_KNOWNHOST_KEY_ECDSA_256:
++ hostkey_method = hostkey_method_ssh_ecdsa_256;
++ break;
++#endif
++ case LIBSSH2_KNOWNHOST_KEY_SSHRSA:
++ hostkey_method = hostkey_method_ssh_rsa;
++ break;
++ case LIBSSH2_KNOWNHOST_KEY_SSHDSS:
++ hostkey_method = hostkey_method_ssh_dss;
++ break;
++ case LIBSSH2_KNOWNHOST_KEY_RSA1:
++ mc_propagate_error (mcerror, 0, "%s",
++ _("sftp: found host key of unsupported type: RSA1"));
++ return FALSE;
++ default:
++ mc_propagate_error (mcerror, 0, "%s %d", _("sftp: unknown host key type:"), mask);
++ return FALSE;
++ }
++
++ rc = libssh2_session_method_pref (sftpfs_super->session, LIBSSH2_METHOD_HOSTKEY,
++ hostkey_method);
++ if (rc < 0)
++ goto err;
++ }
++
++ return TRUE;
++
++ err:
++ {
++ int sftp_errno;
++
++ sftp_errno = libssh2_session_last_errno (sftpfs_super->session);
++ sftpfs_ssherror_to_gliberror (sftpfs_super, sftp_errno, mcerror);
++ }
++ return FALSE;
++}
++
++/* --------------------------------------------------------------------------------------------- */
++
++/**
++ * Write new host + key pair to the ~/.ssh/known_hosts file.
++ *
++ * @param super connection data
++ * @param remote_key he key for the remote host
++ * @param remote_key_len length of @remote_key
++ * @param type_mask info about format of host name, key and key type
++ * @return 0 on success, regular libssh2 error code otherwise
++ *
++ * Thanks the Curl project for the code used in this function.
++ */
++static int
++sftpfs_update_known_hosts (struct vfs_s_super *super, const char *remote_key, size_t remote_key_len,
++ int type_mask)
++{
++ sftpfs_super_t *sftpfs_super = SFTP_SUPER (super);
++ int rc;
++
++ /* add this host + key pair */
++ rc = libssh2_knownhost_addc (sftpfs_super->known_hosts, super->path_element->host, NULL,
++ remote_key, remote_key_len, NULL, 0, type_mask, NULL);
++ if (rc < 0)
++ return rc;
++
++ /* write the entire in-memory list of known hosts to the known_hosts file */
++ rc = libssh2_knownhost_writefile (sftpfs_super->known_hosts, sftpfs_super->known_hosts_file,
++ LIBSSH2_KNOWNHOST_FILE_OPENSSH);
++
++ if (rc < 0)
++ return rc;
++
++ (void) message (D_NORMAL, _("Information"),
++ _("Permanently added\n%s (%s)\nto the list of known hosts."),
++ super->path_element->host, sftpfs_super->ip_address);
++
++ return 0;
++}
++
++/* --------------------------------------------------------------------------------------------- */
++/**
++ * Compute and return readable host key fingerprint hash.
++ *
++ * @param session libssh2 session handle
++ * @return pointer to static buffer on success, NULL otherwise
++ */
++static const char *
++sftpfs_compute_fingerprint_hash (LIBSSH2_SESSION * session)
++{
++ static char result[SHA1_DIGEST_LENGTH * 3 + 1]; /* "XX:" for each byte, and EOL */
++ const char *fingerprint;
++ size_t i;
++
++ /* The fingerprint points to static storage (!), don't free() it. */
++ fingerprint = libssh2_hostkey_hash (session, LIBSSH2_HOSTKEY_HASH_SHA1);
++ if (fingerprint == NULL)
++ return NULL;
++
++ for (i = 0; i < SHA1_DIGEST_LENGTH && i * 3 < sizeof (result) - 1; i++)
++ g_snprintf ((gchar *) (result + i * 3), 4, "%02x:", (guint8) fingerprint[i]);
++
++ /* remove last ":" */
++ result[i * 3 - 1] = '\0';
++
++ return result;
++}
++
++/* --------------------------------------------------------------------------------------------- */
++
+ /**
+- * Recognize authenticaion types supported by remote side and filling internal 'super' structure by
++ * Process host info found in ~/.ssh/known_hosts file.
++ *
++ * @param super connection data
++ * @param mcerror pointer to the error handler
++ * @return TRUE on success, FALSE otherwise
++ *
++ * Thanks the Curl project for the code used in this function.
++ */
++static gboolean
++sftpfs_process_known_host (struct vfs_s_super *super, GError ** mcerror)
++{
++ sftpfs_super_t *sftpfs_super = SFTP_SUPER (super);
++ const char *remote_key;
++ const char *key_type;
++ const char *fingerprint_hash;
++ size_t remote_key_len = 0;
++ int remote_key_type = LIBSSH2_HOSTKEY_TYPE_UNKNOWN;
++ int keybit = 0;
++ struct libssh2_knownhost *host = NULL;
++ int rc;
++ char *msg = NULL;
++ gboolean handle_query = FALSE;
++
++ remote_key = libssh2_session_hostkey (sftpfs_super->session, &remote_key_len, &remote_key_type);
++ if (remote_key == NULL || remote_key_len == 0
++ || remote_key_type == LIBSSH2_HOSTKEY_TYPE_UNKNOWN)
++ {
++ mc_propagate_error (mcerror, 0, "%s", _("sftp: cannot get the remote host key"));
++ return FALSE;
++ }
++
++ switch (remote_key_type)
++ {
++ case LIBSSH2_HOSTKEY_TYPE_RSA:
++ keybit = LIBSSH2_KNOWNHOST_KEY_SSHRSA;
++ key_type = "RSA";
++ break;
++ case LIBSSH2_HOSTKEY_TYPE_DSS:
++ keybit = LIBSSH2_KNOWNHOST_KEY_SSHDSS;
++ key_type = "DSS";
++ break;
++#ifdef LIBSSH2_HOSTKEY_TYPE_ECDSA_256
++ case LIBSSH2_HOSTKEY_TYPE_ECDSA_256:
++ keybit = LIBSSH2_KNOWNHOST_KEY_ECDSA_256;
++ key_type = "ECDSA";
++ break;
++#endif
++#ifdef LIBSSH2_HOSTKEY_TYPE_ECDSA_384
++ case LIBSSH2_HOSTKEY_TYPE_ECDSA_384:
++ keybit = LIBSSH2_KNOWNHOST_KEY_ECDSA_384;
++ key_type = "ECDSA";
++ break;
++#endif
++#ifdef LIBSSH2_HOSTKEY_TYPE_ECDSA_521
++ case LIBSSH2_HOSTKEY_TYPE_ECDSA_521:
++ keybit = LIBSSH2_KNOWNHOST_KEY_ECDSA_521;
++ key_type = "ECDSA";
++ break;
++#endif
++#ifdef LIBSSH2_HOSTKEY_TYPE_ED25519
++ case LIBSSH2_HOSTKEY_TYPE_ED25519:
++ keybit = LIBSSH2_KNOWNHOST_KEY_ED25519;
++ key_type = "ED25519";
++ break;
++#endif
++ default:
++ mc_propagate_error (mcerror, 0, "%s",
++ _("sftp: unsupported key type, can't check remote host key"));
++ return FALSE;
++ }
++
++ fingerprint_hash = sftpfs_compute_fingerprint_hash (sftpfs_super->session);
++ if (fingerprint_hash == NULL)
++ {
++ mc_propagate_error (mcerror, 0, "%s", _("sftp: can't compute host key fingerprint hash"));
++ return FALSE;
++ }
++
++ rc = libssh2_knownhost_checkp (sftpfs_super->known_hosts, super->path_element->host,
++ super->path_element->port, remote_key, remote_key_len,
++ LIBSSH2_KNOWNHOST_TYPE_PLAIN | LIBSSH2_KNOWNHOST_KEYENC_RAW |
++ keybit, &host);
++
++ switch (rc)
++ {
++ default:
++ case LIBSSH2_KNOWNHOST_CHECK_FAILURE:
++ /* something prevented the check to be made */
++ goto err;
++
++ case LIBSSH2_KNOWNHOST_CHECK_MATCH:
++ /* host + key pair matched -- OK */
++ break;
++
++ case LIBSSH2_KNOWNHOST_CHECK_NOTFOUND:
++ /* no host match was found -- add it to the known_hosts file */
++ msg = g_strdup_printf (_("The authenticity of host\n%s (%s)\ncan't be established!\n"
++ "%s key fingerprint hash is\nSHA1:%s.\n"
++ "Do you want to add it to the list of known hosts and continue connecting?"),
++ super->path_element->host, sftpfs_super->ip_address,
++ key_type, fingerprint_hash);
++ /* Select "No" initially */
++ query_set_sel (2);
++ rc = query_dialog (_("Warning"), msg, D_NORMAL, 3, _("&Yes"), _("&Ignore"), _("&No"));
++ g_free (msg);
++ handle_query = TRUE;
++ break;
++
++ case LIBSSH2_KNOWNHOST_CHECK_MISMATCH:
++ msg = g_strdup_printf (_("%s (%s)\nis found in the list of known hosts but\n"
++ "KEYS DO NOT MATCH! THIS COULD BE A MITM ATTACK!\n"
++ "Are you sure you want to add it to the list of known hosts and continue connecting?"),
++ super->path_element->host, sftpfs_super->ip_address);
++ /* Select "No" initially */
++ query_set_sel (2);
++ rc = query_dialog (MSG_ERROR, msg, D_ERROR, 3, _("&Yes"), _("&Ignore"), _("&No"));
++ g_free (msg);
++ handle_query = TRUE;
++ break;
++ }
++
++ if (handle_query)
++ switch (rc)
++ {
++ case 0:
++ /* Yes: add this host + key pair, continue connecting */
++ if (sftpfs_update_known_hosts (super, remote_key, remote_key_len,
++ LIBSSH2_KNOWNHOST_TYPE_PLAIN
++ | LIBSSH2_KNOWNHOST_KEYENC_RAW | keybit) < 0)
++ goto err;
++ break;
++ case 1:
++ /* Ignore: do not add this host + key pair, continue connecting anyway */
++ break;
++ case 2:
++ default:
++ mc_propagate_error (mcerror, 0, "%s", _("sftp: host key verification failed"));
++ /* No: abort connection */
++ goto err;
++ }
++
++ return TRUE;
++
++ err:
++ {
++ int sftp_errno;
++
++ sftp_errno = libssh2_session_last_errno (sftpfs_super->session);
++ sftpfs_ssherror_to_gliberror (sftpfs_super, sftp_errno, mcerror);
++ }
++
++ return FALSE;
++}
++
++/* --------------------------------------------------------------------------------------------- */
++/**
++ * Recognize authentication types supported by remote side and filling internal 'super' structure by
+ * proper enum's values.
+ *
+ * @param super connection data
+@@ -461,6 +867,9 @@ sftpfs_open_connection (struct vfs_s_super *super, GError ** mcerror)
+ if (sftpfs_super->session == NULL)
+ return (-1);
+
++ if (!sftpfs_read_known_hosts (super, mcerror))
++ return (-1);
++
+ /* ... start it up. This will trade welcome banners, exchange keys,
+ * and setup crypto, compression, and MAC layers
+ */
+@@ -475,13 +884,8 @@ sftpfs_open_connection (struct vfs_s_super *super, GError ** mcerror)
+ return (-1);
+ }
+
+- /* At this point we havn't yet authenticated. The first thing to do
+- * is check the hostkey's fingerprint against our known hosts Your app
+- * may have it hard coded, may go to a file, may present it to the
+- * user, that's your call
+- */
+- sftpfs_super->fingerprint =
+- libssh2_hostkey_hash (sftpfs_super->session, LIBSSH2_HOSTKEY_HASH_SHA1);
++ if (!sftpfs_process_known_host (super, mcerror))
++ return (-1);
+
+ if (!sftpfs_recognize_auth_types (super))
+ {
+@@ -538,7 +942,13 @@ sftpfs_close_connection (struct vfs_s_super *super, const char *shutdown_message
+ sftpfs_super->agent = NULL;
+ }
+
+- sftpfs_super->fingerprint = NULL;
++ if (sftpfs_super->known_hosts != NULL)
++ {
++ libssh2_knownhost_free (sftpfs_super->known_hosts);
++ sftpfs_super->known_hosts = NULL;
++ }
++
++ MC_PTR_FREE (sftpfs_super->known_hosts_file);
+
+ if (sftpfs_super->session != NULL)
+ {
+diff --git a/src/vfs/sftpfs/internal.h b/src/vfs/sftpfs/internal.h
+index 5616fb8990..643ce5e3cc 100644
+--- a/src/vfs/sftpfs/internal.h
++++ b/src/vfs/sftpfs/internal.h
+@@ -42,6 +42,9 @@ typedef struct
+ sftpfs_auth_type_t auth_type;
+ sftpfs_auth_type_t config_auth_type;
+
++ LIBSSH2_KNOWNHOSTS *known_hosts;
++ char *known_hosts_file;
++
+ LIBSSH2_SESSION *session;
+ LIBSSH2_SFTP *sftp_session;
+
+@@ -51,7 +54,7 @@ typedef struct
+ char *privkey;
+
+ int socket_handle;
+- const char *fingerprint;
++ const char *ip_address;
+ vfs_path_element_t *original_connection_info;
+ } sftpfs_super_t;
+