[meta-networking] proftpd: Fix CVE-2023-48795

Upstream-Status: Backport from https://github.com/proftpd/proftpd/commit/bcec15efe6c53dac40420731013f1cd2fd54123b

Signed-off-by: Vijay Anusuri <vanusuri@mvista.com>
---
 .../proftpd/files/CVE-2023-48795.patch        | 751 ++++++++++++++++++
 .../recipes-daemons/proftpd/proftpd_1.3.7c.bb |   1 +
 2 files changed, 752 insertions(+)
 create mode 100644 meta-networking/recipes-daemons/proftpd/files/CVE-2023-48795.patch

Hi Team,

Please ignore this patch. This particular patch was intended for the
`scarthgap` branch, not `master`. I have already sent a separate patch for
`scarthgap`.

Thanks,
Vijay
On Mon, Oct 20, 2025 at 5:00 PM Vijay Anusuri <vanusuri@mvista.com> wrote:

> Upstream-Status: Backport from
> https://github.com/proftpd/proftpd/commit/bcec15efe6c53dac40420731013f1cd2fd54123b
>
> Signed-off-by: Vijay Anusuri <vanusuri@mvista.com>
> ---
>  .../proftpd/files/CVE-2023-48795.patch        | 751 ++++++++++++++++++
>  .../recipes-daemons/proftpd/proftpd_1.3.7c.bb |   1 +
>  2 files changed, 752 insertions(+)
>  create mode 100644
> meta-networking/recipes-daemons/proftpd/files/CVE-2023-48795.patch
>
> diff --git
> a/meta-networking/recipes-daemons/proftpd/files/CVE-2023-48795.patch
> b/meta-networking/recipes-daemons/proftpd/files/CVE-2023-48795.patch
> new file mode 100644
> index 0000000000..39def781fb
> --- /dev/null
> +++ b/meta-networking/recipes-daemons/proftpd/files/CVE-2023-48795.patch
> @@ -0,0 +1,751 @@
> +From bcec15efe6c53dac40420731013f1cd2fd54123b Mon Sep 17 00:00:00 2001
> +From: TJ Saunders <tj@castaglia.org>
> +Date: Tue, 19 Dec 2023 18:55:58 -0800
> +Subject: [PATCH] Issue #1760: Implement the "strict KEX" mitigations for
> the
> + Terrapin SSH protocol attack (CVE-2023-48795).
> +
> +Upstream-Status: Backport [
> https://github.com/proftpd/proftpd/commit/bcec15efe6c53dac40420731013f1cd2fd54123b
> ]
> +CVE: CVE-2023-48795
> +Signed-off-by: Vijay Anusuri <vanusuri@mvista.com>
> +---
> + contrib/mod_sftp/kex.c                        | 124 ++++++++--
> + contrib/mod_sftp/mod_sftp.c                   |   8 +-
> + contrib/mod_sftp/mod_sftp.h.in                |   1 +
> + contrib/mod_sftp/packet.c                     |  12 +
> + contrib/mod_sftp/packet.h                     |   9 +-
> + contrib/mod_sftp/tap.c                        |  26 ++-
> + contrib/mod_sftp/tap.h                        |   5 +-
> + doc/contrib/mod_sftp.html                     |  15 +-
> + tests/t/lib/ProFTPD/Tests/Modules/mod_sftp.pm | 217 ++++++++++++++++++
> + 9 files changed, 380 insertions(+), 37 deletions(-)
> +
> +diff --git a/contrib/mod_sftp/kex.c b/contrib/mod_sftp/kex.c
> +index 754bd9e87..c1caa1c27 100644
> +--- a/contrib/mod_sftp/kex.c
> ++++ b/contrib/mod_sftp/kex.c
> +@@ -149,6 +149,13 @@ static struct sftp_kex *kex_first_kex = NULL;
> + static struct sftp_kex *kex_rekey_kex = NULL;
> + static int kex_sent_kexinit = FALSE;
> +
> ++/* Using strict kex?  Note that we maintain this value here, rather than
> ++ * in the sftp_kex struct, so that any "use strict KEX" flag set via the
> ++ * first KEXINIT is used through any subsequent KEXINITs.
> ++ */
> ++static int use_strict_kex = FALSE;
> ++static int kex_done_first_kex = FALSE;
> ++
> + /* Diffie-Hellman group moduli */
> +
> + static const char *dh_group1_str =
> +@@ -1593,6 +1600,16 @@ static const char *get_kexinit_exchange_list(pool
> *p) {
> +     res = pstrcat(p, res, *res ? "," : "", pstrdup(p, "ext-info-s"),
> NULL);
> +   }
> +
> ++  if (!(sftp_opts & SFTP_OPT_NO_STRICT_KEX)) {
> ++    /* Indicate support for OpenSSH's custom "strict KEX" mode extension,
> ++     * but only if we have not done/completed our first KEX.
> ++     */
> ++    if (kex_done_first_kex == FALSE) {
> ++      res = pstrcat(p, res, *res ? "," : "",
> ++        pstrdup(p, "kex-strict-s-v00@openssh.com"), NULL);
> ++    }
> ++  }
> ++
> +   return res;
> + }
> +
> +@@ -2174,6 +2191,21 @@ static int get_session_names(struct sftp_kex *kex,
> int *correct_guess) {
> +     pr_trace_msg(trace_channel, 20, "client %s EXT_INFO support",
> +       kex->use_ext_info ? "signaled" : "did not signal" );
> +
> ++    if (!(sftp_opts & SFTP_OPT_NO_STRICT_KEX)) {
> ++      /* Did the client indicate "strict kex" support (Issue 1760)?
> ++       *
> ++       * Note that we only check for this if it is our first KEXINIT.
> ++       * The "strict kex" extension is ignored in any subsequent
> KEXINITs, as
> ++       * for rekeys.
> ++       */
> ++      if (kex_done_first_kex == FALSE) {
> ++        use_strict_kex = sftp_misc_namelist_contains(kex->pool,
> ++          client_list, "kex-strict-c-v00@openssh.com");
> ++        pr_trace_msg(trace_channel, 20, "client %s strict KEX support",
> ++          use_strict_kex ? "signaled" : "did not signal" );
> ++      }
> ++    }
> ++
> +   } else {
> +     (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
> +       "no shared key exchange algorithm found (client sent '%s', server
> sent "
> +@@ -4406,7 +4438,6 @@ static int handle_kex_ecdh(struct ssh2_packet *pkt,
> struct sftp_kex *kex) {
> +   destroy_pool(pkt->pool);
> +   return 0;
> + }
> +-
> + #endif /* PR_USE_OPENSSL_ECC */
> +
> + static struct ssh2_packet *read_kex_packet(pool *p, struct sftp_kex *kex,
> +@@ -4457,6 +4488,10 @@ static struct ssh2_packet *read_kex_packet(pool
> *p, struct sftp_kex *kex,
> +     /* Per RFC 4253, Section 11, DEBUG, DISCONNECT, IGNORE, and
> UNIMPLEMENTED
> +      * messages can occur at any time, even during KEX.  We have to be
> prepared
> +      * for this, and Do The Right Thing(tm).
> ++     *
> ++     * However, due to the Terrapin attack, if we are using a "strict
> KEX"
> ++     * mode, then only DISCONNECT messages can occur during KEX; DEBUG,
> ++     * IGNORE, and UNIMPLEMENTED messages will lead to disconnecting.
> +      */
> +
> +     mesg_type = sftp_ssh2_packet_get_mesg_type(pkt);
> +@@ -4485,35 +4520,43 @@ static struct ssh2_packet *read_kex_packet(pool
> *p, struct sftp_kex *kex,
> +     }
> +
> +     switch (mesg_type) {
> +-      case SFTP_SSH2_MSG_DEBUG:
> +-        sftp_ssh2_packet_handle_debug(pkt);
> +-        pr_response_set_pool(NULL);
> +-        pkt = NULL;
> +-        break;
> +-
> ++      /* DISCONNECT messages are always allowed. */
> +       case SFTP_SSH2_MSG_DISCONNECT:
> +         sftp_ssh2_packet_handle_disconnect(pkt);
> +         pr_response_set_pool(NULL);
> +         pkt = NULL;
> +         break;
> +
> ++      case SFTP_SSH2_MSG_DEBUG:
> ++        if (use_strict_kex == FALSE) {
> ++          sftp_ssh2_packet_handle_debug(pkt);
> ++          pr_response_set_pool(NULL);
> ++          pkt = NULL;
> ++          break;
> ++        }
> ++
> +       case SFTP_SSH2_MSG_IGNORE:
> +-        sftp_ssh2_packet_handle_ignore(pkt);
> +-        pr_response_set_pool(NULL);
> +-        pkt = NULL;
> +-        break;
> ++        if (use_strict_kex == FALSE) {
> ++          sftp_ssh2_packet_handle_ignore(pkt);
> ++          pr_response_set_pool(NULL);
> ++          pkt = NULL;
> ++          break;
> ++        }
> +
> +       case SFTP_SSH2_MSG_UNIMPLEMENTED:
> +-        sftp_ssh2_packet_handle_unimplemented(pkt);
> +-        pr_response_set_pool(NULL);
> +-        pkt = NULL;
> +-        break;
> ++        if (use_strict_kex == FALSE) {
> ++          sftp_ssh2_packet_handle_unimplemented(pkt);
> ++          pr_response_set_pool(NULL);
> ++          pkt = NULL;
> ++          break;
> ++        }
> +
> +       default:
> +         /* For any other message type, it's considered a protocol error.
> */
> +         (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
> +-          "received %s (%d) unexpectedly, disconnecting",
> +-          sftp_ssh2_packet_get_mesg_type_desc(mesg_type), mesg_type);
> ++          "received %s (%d) unexpectedly%s, disconnecting",
> ++          sftp_ssh2_packet_get_mesg_type_desc(mesg_type), mesg_type,
> ++          use_strict_kex ? " during strict KEX" : "");
> +         pr_response_set_pool(NULL);
> +         destroy_kex(kex);
> +         destroy_pool(pkt->pool);
> +@@ -4534,7 +4577,7 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +    * initial connect (kex_first_kex not null), or because we
> +    * are in a server-initiated rekeying (kex_rekey_kex not null).
> +    */
> +-  if (kex_first_kex) {
> ++  if (kex_first_kex != NULL) {
> +     kex = kex_first_kex;
> +
> +     /* We need to assign the client/server versions, which this struct
> +@@ -4543,7 +4586,7 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +     kex->client_version = kex_client_version;
> +     kex->server_version = kex_server_version;
> +
> +-  } else if (kex_rekey_kex) {
> ++  } else if (kex_rekey_kex != NULL) {
> +     kex = kex_rekey_kex;
> +
> +   } else {
> +@@ -4579,6 +4622,24 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +     return -1;
> +   }
> +
> ++  if (use_strict_kex == TRUE &&
> ++      kex_done_first_kex == FALSE) {
> ++    uint32_t client_seqno;
> ++
> ++    client_seqno = sftp_ssh2_packet_get_client_seqno();
> ++    if (client_seqno != 1) {
> ++      /* Receiving any messages other than a KEXINIT as the first client
> ++       * message indicates the possibility of the Terrapin attack being
> ++       * conducted (Issue 1760).  Thus we disconnect the client in such
> ++       * cases.
> ++       */
> ++      (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
> ++        "'strict KEX' violation, as KEXINIT was not the first message;
> disconnecting");
> ++      destroy_kex(kex);
> ++      SFTP_DISCONNECT_CONN(SFTP_SSH2_DISCONNECT_BY_APPLICATION, NULL);
> ++    }
> ++  }
> ++
> +   /* Once we have received the client KEXINIT message, we can compare
> what we
> +    * want to send against what we already received from the client.
> +    *
> +@@ -4637,7 +4698,7 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +
> +       destroy_pool(pkt->pool);
> +
> +-      if (!kex_sent_kexinit) {
> ++      if (kex_sent_kexinit == FALSE) {
> +         pkt = sftp_ssh2_packet_create(kex_pool);
> +         res = write_kexinit(pkt, kex);
> +         if (res < 0) {
> +@@ -4660,7 +4721,7 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +       }
> +     }
> +
> +-    if (!kex_sent_kexinit) {
> ++    if (kex_sent_kexinit == FALSE) {
> +       pkt = sftp_ssh2_packet_create(kex_pool);
> +       res = write_kexinit(pkt, kex);
> +       if (res < 0) {
> +@@ -4785,7 +4846,7 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +     NULL, 1, SFTP_SSH2_MSG_NEWKEYS);
> +
> +   /* If we didn't send our NEWKEYS message earlier, do it now. */
> +-  if (!sent_newkeys) {
> ++  if (sent_newkeys == FALSE) {
> +     struct ssh2_packet *pkt2;
> +
> +     pr_trace_msg(trace_channel, 9, "sending NEWKEYS message to client");
> +@@ -4809,6 +4870,11 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +     destroy_pool(pkt2->pool);
> +   }
> +
> ++  if (use_strict_kex == TRUE) {
> ++    sftp_ssh2_packet_reset_client_seqno();
> ++    sftp_ssh2_packet_reset_server_seqno();
> ++  }
> ++
> +   /* Last but certainly not least, set up the keys for encryption and
> +    * authentication, based on H and K.
> +    */
> +@@ -4828,6 +4894,9 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +   destroy_pool(pkt->pool);
> +   cmd = NULL;
> +
> ++  /* We've now completed our KEX, possibly our first. */
> ++  kex_done_first_kex = TRUE;
> ++
> +   /* If extension negotiation has not been disabled, AND if we have not
> +    * received a service request, AND if the client sent "ext-info-c",
> THEN
> +    * send our EXT_INFO.  We do not want send this during rekeys.
> +@@ -4864,6 +4933,12 @@ int sftp_kex_handle(struct ssh2_packet *pkt) {
> +     cmd = NULL;
> +   }
> +
> ++  /* Only start the TAP timer after we have completed our first KEX.
> ++   * Otherwise, we risk sending "illegal" packets prior to, or during,
> ++   * a "strict KEX" session (Issue 1760).
> ++   */
> ++  sftp_tap_start_policy();
> ++
> +   /* Reset this flag for the next time through. */
> +   kex_sent_kexinit = FALSE;
> +
> +@@ -4893,7 +4968,7 @@ int sftp_kex_free(void) {
> +     destroy_kex(rekey_kex);
> +   }
> +
> +-  if (kex_pool) {
> ++  if (kex_pool != NULL) {
> +     destroy_pool(kex_pool);
> +     kex_pool = NULL;
> +   }
> +@@ -5065,7 +5140,7 @@ int sftp_kex_send_first_kexinit(void) {
> +   struct ssh2_packet *pkt;
> +   int res;
> +
> +-  if (!kex_pool) {
> ++  if (kex_pool == NULL) {
> +     kex_pool = make_sub_pool(sftp_pool);
> +     pr_pool_tag(kex_pool, "Kex Pool");
> +   }
> +@@ -5100,4 +5175,3 @@ int sftp_kex_send_first_kexinit(void) {
> +   destroy_pool(pkt->pool);
> +   return 0;
> + }
> +-
> +diff --git a/contrib/mod_sftp/mod_sftp.c b/contrib/mod_sftp/mod_sftp.c
> +index b84b1a77b..2406ea611 100644
> +--- a/contrib/mod_sftp/mod_sftp.c
> ++++ b/contrib/mod_sftp/mod_sftp.c
> +@@ -1,6 +1,6 @@
> + /*
> +  * ProFTPD - mod_sftp
> +- * Copyright (c) 2008-2020 TJ Saunders
> ++ * Copyright (c) 2008-2023 TJ Saunders
> +  *
> +  * This program is free software; you can redistribute it and/or modify
> +  * it under the terms of the GNU General Public License as published by
> +@@ -1411,8 +1411,9 @@ MODRET set_sftpoptions(cmd_rec *cmd) {
> +   config_rec *c;
> +   unsigned long opts = 0UL;
> +
> +-  if (cmd->argc-1 == 0)
> ++  if (cmd->argc-1 == 0) {
> +     CONF_ERROR(cmd, "wrong number of parameters");
> ++  }
> +
> +   CHECK_CONF(cmd, CONF_ROOT|CONF_VIRTUAL|CONF_GLOBAL);
> +
> +@@ -1476,6 +1477,9 @@ MODRET set_sftpoptions(cmd_rec *cmd) {
> +     } else if (strcmp(cmd->argv[i], "NoExtensionNegotiation") == 0) {
> +       opts |= SFTP_OPT_NO_EXT_INFO;
> +
> ++    } else if (strcmp(cmd->argv[i], "NoStrictKex") == 0) {
> ++      opts |= SFTP_OPT_NO_STRICT_KEX;
> ++
> +     } else {
> +       CONF_ERROR(cmd, pstrcat(cmd->tmp_pool, ": unknown SFTPOption '",
> +         cmd->argv[i], "'", NULL));
> +diff --git a/contrib/mod_sftp/mod_sftp.h.in b/contrib/mod_sftp/
> mod_sftp.h.in
> +index 065981c31..adcf71276 100644
> +--- a/contrib/mod_sftp/mod_sftp.h.in
> ++++ b/contrib/mod_sftp/mod_sftp.h.in
> +@@ -131,6 +131,7 @@
> + #define SFTP_OPT_IGNORE_SFTP_SET_XATTRS               0x04000
> + #define SFTP_OPT_INCLUDE_SFTP_TIMES           0x08000
> + #define SFTP_OPT_NO_EXT_INFO                  0x10000
> ++#define SFTP_OPT_NO_STRICT_KEX                        0x040000
> +
> + /* mod_sftp service flags */
> + #define SFTP_SERVICE_FL_SFTP          0x0001
> +diff --git a/contrib/mod_sftp/packet.c b/contrib/mod_sftp/packet.c
> +index b0067ea80..d8c97e92b 100644
> +--- a/contrib/mod_sftp/packet.c
> ++++ b/contrib/mod_sftp/packet.c
> +@@ -1742,6 +1742,18 @@ int sftp_ssh2_packet_rekey_set_size(off_t size) {
> +   return 0;
> + }
> +
> ++uint32_t sftp_ssh2_packet_get_client_seqno(void) {
> ++  return packet_client_seqno;
> ++}
> ++
> ++void sftp_ssh2_packet_reset_client_seqno(void) {
> ++  packet_client_seqno = 0;
> ++}
> ++
> ++void sftp_ssh2_packet_reset_server_seqno(void) {
> ++  packet_server_seqno = 0;
> ++}
> ++
> + int sftp_ssh2_packet_send_version(void) {
> +   if (!sent_version_id) {
> +     int res;
> +diff --git a/contrib/mod_sftp/packet.h b/contrib/mod_sftp/packet.h
> +index a424e9b25..fe538cbd7 100644
> +--- a/contrib/mod_sftp/packet.h
> ++++ b/contrib/mod_sftp/packet.h
> +@@ -1,6 +1,6 @@
> + /*
> +  * ProFTPD - mod_sftp packet IO
> +- * Copyright (c) 2008-2020 TJ Saunders
> ++ * Copyright (c) 2008-2023 TJ Saunders
> +  *
> +  * This program is free software; you can redistribute it and/or modify
> +  * it under the terms of the GNU General Public License as published by
> +@@ -107,6 +107,13 @@ int sftp_ssh2_packet_rekey_reset(void);
> + int sftp_ssh2_packet_rekey_set_seqno(uint32_t);
> + int sftp_ssh2_packet_rekey_set_size(off_t);
> +
> ++/* These are used for implementing the "strict KEX" mitigations of the
> Terrapin
> ++ * attack (Issue 1760).
> ++ */
> ++uint32_t sftp_ssh2_packet_get_client_seqno(void);
> ++void sftp_ssh2_packet_reset_client_seqno(void);
> ++void sftp_ssh2_packet_reset_server_seqno(void);
> ++
> + int sftp_ssh2_packet_send_version(void);
> + int sftp_ssh2_packet_set_poll_timeout(int);
> + int sftp_ssh2_packet_set_version(const char *);
> +diff --git a/contrib/mod_sftp/tap.c b/contrib/mod_sftp/tap.c
> +index 95f388e43..7eaf959e2 100644
> +--- a/contrib/mod_sftp/tap.c
> ++++ b/contrib/mod_sftp/tap.c
> +@@ -1,6 +1,6 @@
> + /*
> +  * ProFTPD - mod_sftp traffic analysis protection
> +- * Copyright (c) 2008-2016 TJ Saunders
> ++ * Copyright (c) 2008-2023 TJ Saunders
> +  *
> +  * This program is free software; you can redistribute it and/or modify
> +  * it under the terms of the GNU General Public License as published by
> +@@ -149,7 +149,6 @@ static void set_policy_chance(struct sftp_tap_policy
> *policy) {
> + }
> +
> + static void set_policy_timer(struct sftp_tap_policy *policy) {
> +-
> +   /* Start a timer which checks the last times we received and sent
> packets.
> +    * From there, we may want to inject a TAP message, depending on the
> +    * policy.
> +@@ -177,6 +176,16 @@ int sftp_tap_send_packet(void) {
> +   int rnd;
> +   unsigned int chance;
> +
> ++  /* Due to chances of violating client-side "strict KEX" Terrapin
> ++   * mitigations, we will not send packets if we are in the middle of a
> KEX.
> ++   */
> ++  if (!(sftp_sess_state & SFTP_SESS_STATE_HAVE_KEX) ||
> ++      (sftp_sess_state & SFTP_SESS_STATE_REKEYING)) {
> ++    pr_trace_msg(trace_channel, 11,
> ++      "unwilling to send TAP packet during KEX");
> ++    return 0;
> ++  }
> ++
> +   if (!sftp_interop_supports_feature(SFTP_SSH2_FEAT_IGNORE_MSG)) {
> +     pr_trace_msg(trace_channel, 3,
> +       "unable to send TAP packet: IGNORE not supported by client");
> +@@ -205,7 +214,7 @@ int sftp_tap_send_packet(void) {
> +     struct ssh2_packet *pkt;
> +     unsigned int max_datalen = 8192;
> +
> +-    if (curr_policy.max_datalen) {
> ++    if (curr_policy.max_datalen > 0) {
> +       max_datalen = curr_policy.max_datalen;
> +     }
> +
> +@@ -246,15 +255,15 @@ int sftp_tap_send_packet(void) {
> + int sftp_tap_set_policy(const char *policy) {
> +   register unsigned int i;
> +
> +-  if (tap_pool) {
> ++  if (tap_pool != NULL) {
> +
> +     /* Special case: IFF the existing policy is 'none' AND the given
> +      * policy is 'rogaway', just return.  The 'none' policy must have
> been
> +      * explicitly configured, and it should override the automatic use of
> +      * the 'rogaway' policy.
> +      */
> +-    if (strncmp(curr_policy.policy, "none", 5) == 0 &&
> +-        strncasecmp(policy, "rogaway", 8) == 0) {
> ++    if (strcasecmp(curr_policy.policy, "none") == 0 &&
> ++        strcasecmp(policy, "rogaway") == 0) {
> +       (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION,
> +         "'none' traffic policy explicitly configured, ignoring '%s'
> policy",
> +         policy);
> +@@ -278,7 +287,6 @@ int sftp_tap_set_policy(const char *policy) {
> +     if (strcasecmp(tap_policies[i].policy, policy) == 0) {
> +       copy_policy(&curr_policy, &(tap_policies[i]));
> +       set_policy_chance(&curr_policy);
> +-      set_policy_timer(&curr_policy);
> +       return 0;
> +     }
> +   }
> +@@ -286,3 +294,7 @@ int sftp_tap_set_policy(const char *policy) {
> +   errno = ENOENT;
> +   return -1;
> + }
> ++
> ++void sftp_tap_start_policy(void) {
> ++  set_policy_timer(&curr_policy);
> ++}
> +diff --git a/contrib/mod_sftp/tap.h b/contrib/mod_sftp/tap.h
> +index 4a4c065d2..312223595 100644
> +--- a/contrib/mod_sftp/tap.h
> ++++ b/contrib/mod_sftp/tap.h
> +@@ -1,6 +1,6 @@
> + /*
> +  * ProFTPD - mod_sftp traffic analysis protection
> +- * Copyright (c) 2008-2016 TJ Saunders
> ++ * Copyright (c) 2008-2013 TJ Saunders
> +  *
> +  * This program is free software; you can redistribute it and/or modify
> +  * it under the terms of the GNU General Public License as published by
> +@@ -63,4 +63,7 @@ int sftp_tap_send_packet(void);
> +  */
> + int sftp_tap_set_policy(const char *);
> +
> ++/* Sets the configured TAP policy in motion. */
> ++void sftp_tap_start_policy(void);
> ++
> + #endif /* MOD_SFTP_TAP_H */
> +diff --git a/doc/contrib/mod_sftp.html b/doc/contrib/mod_sftp.html
> +index 60c3436fa..cfc639d05 100644
> +--- a/doc/contrib/mod_sftp.html
> ++++ b/doc/contrib/mod_sftp.html
> +@@ -1186,6 +1186,19 @@ The currently implemented options are:
> +     <code>proftpd-1.3.7rc4</code>.
> +   </li>
> +
> ++  <p>
> ++  <li><code>NoStrictKex</code><br>
> ++    <p>
> ++    By default, <code>mod_sftp</code> will honor/support the OpenSSH
> ++    "strict KEX" mode extension, "kex-strict-c-v00@openssh.com" and
> ++    "kex-strict-s-v00@openssh.com".  Use this option to disable support
> for
> ++    these custom OpenSSH extensions.
> ++
> ++    <p>
> ++    <b>Note</b> that this option first appeared in
> ++    <code>proftpd-1.3.9rc1</code>.
> ++  </li>
> ++
> +   <p>
> +   <li><code>OldProtocolCompat</code><br>
> +     <p>
> +@@ -2642,7 +2655,7 @@ deal with this issue, then, you can hopefully
> upgrade to ProFTPD 1.3.6 or later,
> + <p>
> + <hr>
> + <font size=2><b><i>
> +-&copy; Copyright 2008-2021 TJ Saunders<br>
> ++&copy; Copyright 2008-2023 TJ Saunders<br>
> +  All Rights Reserved<br>
> + </i></b></font>
> + <hr>
> +diff --git a/tests/t/lib/ProFTPD/Tests/Modules/mod_sftp.pm
> b/tests/t/lib/ProFTPD/Tests/Modules/mod_sftp.pm
> +index b4bdf516b..8c2be5465 100644
> +--- a/tests/t/lib/ProFTPD/Tests/Modules/mod_sftp.pm
> ++++ b/tests/t/lib/ProFTPD/Tests/Modules/mod_sftp.pm
> +@@ -87,6 +87,11 @@ my $TESTS = {
> +     test_class => [qw(forking ssh2)],
> +   },
> +
> ++  ssh2_ext_kex_strict_terrapin_issue1760 => {
> ++    order => ++$order,
> ++    test_class => [qw(bug forking ssh2)],
> ++  },
> ++
> +   ssh2_hostkey_rsa => {
> +     order => ++$order,
> +     test_class => [qw(forking ssh2)],
> +@@ -3885,6 +3890,218 @@ EOC
> +   unlink($log_file);
> + }
> +
> ++sub ssh2_ext_kex_strict_terrapin_issue1760 {
> ++  my $self = shift;
> ++  my $tmpdir = $self->{tmpdir};
> ++  my $setup = test_setup($tmpdir, 'sftp');
> ++
> ++  my $rsa_host_key =
> File::Spec->rel2abs('t/etc/modules/mod_sftp/ssh_host_rsa_key');
> ++  my $dsa_host_key =
> File::Spec->rel2abs('t/etc/modules/mod_sftp/ssh_host_dsa_key');
> ++
> ++  my $rsa_priv_key =
> File::Spec->rel2abs('t/etc/modules/mod_sftp/test_rsa_key');
> ++  my $rsa_pub_key =
> File::Spec->rel2abs('t/etc/modules/mod_sftp/test_rsa_key.pub');
> ++  my $rsa_rfc4716_key =
> File::Spec->rel2abs('t/etc/modules/mod_sftp/authorized_rsa_keys');
> ++
> ++  my $authorized_keys = File::Spec->rel2abs("$tmpdir/.authorized_keys");
> ++  unless (copy($rsa_rfc4716_key, $authorized_keys)) {
> ++    die("Can't copy $rsa_rfc4716_key to $authorized_keys: $!");
> ++  }
> ++
> ++  my $ssh_config = File::Spec->rel2abs("$tmpdir/ssh.conf");
> ++  if (open(my $fh, "> $ssh_config")) {
> ++    print $fh <<EOC;
> ++HostKeyAlgorithms rsa-sha2-256
> ++IdentityAgent none
> ++PubkeyAcceptedKeyTypes rsa-sha2-256
> ++EOC
> ++    unless (close($fh)) {
> ++      die("Can't write $ssh_config: $!");
> ++    }
> ++
> ++  } else {
> ++    die("Can't open $ssh_config: $!");
> ++  }
> ++
> ++  my $batch_file = File::Spec->rel2abs("$tmpdir/sftp-batch.conf");
> ++  if (open(my $fh, "> $batch_file")) {
> ++    print $fh "ls -l\n";
> ++
> ++    unless (close($fh)) {
> ++      die("Can't write $batch_file: $!");
> ++    }
> ++
> ++  } else {
> ++    die("Can't open $batch_file: $!");
> ++  }
> ++
> ++  my $config = {
> ++    PidFile => $setup->{pid_file},
> ++    ScoreboardFile => $setup->{scoreboard_file},
> ++    SystemLog => $setup->{log_file},
> ++    TraceLog => $setup->{log_file},
> ++    Trace => 'ssh2:30 sftp:20 scp:20',
> ++
> ++    AuthUserFile => $setup->{auth_user_file},
> ++    AuthGroupFile => $setup->{auth_group_file},
> ++    AuthOrder => 'mod_auth_file.c',
> ++
> ++    IfModules => {
> ++      'mod_delay.c' => {
> ++        DelayEngine => 'off',
> ++      },
> ++
> ++      'mod_sftp.c' => [
> ++        "SFTPEngine on",
> ++        "SFTPLog $setup->{log_file}",
> ++
> ++        "SFTPHostKey $rsa_host_key",
> ++        "SFTPHostKey $dsa_host_key",
> ++
> ++        "SFTPAuthorizedUserKeys file:~/.authorized_keys",
> ++      ],
> ++    },
> ++  };
> ++
> ++  my ($port, $config_user, $config_group) =
> config_write($setup->{config_file},
> ++    $config);
> ++
> ++  # Open pipes, for use between the parent and child processes.
> Specifically,
> ++  # the child will indicate when it's done with its test by writing a
> message
> ++  # to the parent.
> ++  my ($rfh, $wfh);
> ++  unless (pipe($rfh, $wfh)) {
> ++    die("Can't open pipe: $!");
> ++  }
> ++
> ++  require Net::SSH2;
> ++
> ++  my $ex;
> ++
> ++  # Fork child
> ++  $self->handle_sigchld();
> ++  defined(my $pid = fork()) or die("Can't fork: $!");
> ++  if ($pid) {
> ++    eval {
> ++      # We use OpenSSH-9.6p1 to test our "strict KEX" Terrapin
> mitigations.
> ++      my $sftp = '/Users/tj/local/openssh-9.6p1/bin/sftp';
> ++
> ++      my @cmd = (
> ++        $sftp,
> ++        '-F',
> ++        $ssh_config,
> ++        '-oBatchMode=yes',
> ++        '-oCheckHostIP=no',
> ++        '-oCompression=yes',
> ++        "-oPort=$port",
> ++        "-oIdentityFile=$rsa_priv_key",
> ++        '-oPubkeyAuthentication=yes',
> ++        '-oStrictHostKeyChecking=no',
> ++        '-oUserKnownHostsFile=/dev/null',
> ++        '-vvv',
> ++        '-b',
> ++        $batch_file,
> ++        "$setup->{user}\@127.0.0.1",
> ++      );
> ++
> ++      my $sftp_rh = IO::Handle->new();
> ++      my $sftp_wh = IO::Handle->new();
> ++      my $sftp_eh = IO::Handle->new();
> ++
> ++      $sftp_wh->autoflush(1);
> ++
> ++      sleep(1);
> ++
> ++      local $SIG{CHLD} = 'DEFAULT';
> ++
> ++      # Make sure that the perms on the priv key are what OpenSSH wants
> ++      unless (chmod(0400, $rsa_priv_key)) {
> ++        die("Can't set perms on $rsa_priv_key to 0400: $!");
> ++      }
> ++
> ++      if ($ENV{TEST_VERBOSE}) {
> ++        print STDERR "Executing: ", join(' ', @cmd), "\n";
> ++      }
> ++
> ++      my $sftp_pid = open3($sftp_wh, $sftp_rh, $sftp_eh, @cmd);
> ++      waitpid($sftp_pid, 0);
> ++      my $exit_status = $?;
> ++
> ++      # Restore the perms on the priv key
> ++      unless (chmod(0644, $rsa_priv_key)) {
> ++        die("Can't set perms on $rsa_priv_key to 0644: $!");
> ++      }
> ++
> ++      my ($res, $errstr);
> ++      if ($exit_status >> 8 == 0) {
> ++        $errstr = join('', <$sftp_eh>);
> ++        $res = 0;
> ++
> ++      } else {
> ++        $errstr = join('', <$sftp_eh>);
> ++        if ($ENV{TEST_VERBOSE}) {
> ++          print STDERR "Stderr: $errstr\n";
> ++        }
> ++
> ++        $res = 1;
> ++      }
> ++
> ++      unless ($res == 0) {
> ++        die("Can't list files on server: $errstr");
> ++      }
> ++    };
> ++    if ($@) {
> ++      $ex = $@;
> ++    }
> ++
> ++    $wfh->print("done\n");
> ++    $wfh->flush();
> ++
> ++  } else {
> ++    eval { server_wait($setup->{config_file}, $rfh) };
> ++    if ($@) {
> ++      warn($@);
> ++      exit 1;
> ++    }
> ++
> ++    exit 0;
> ++  }
> ++
> ++  # Stop server
> ++  server_stop($setup->{pid_file});
> ++  $self->assert_child_ok($pid);
> ++
> ++  eval {
> ++    if (open(my $fh, "< $setup->{log_file}")) {
> ++      my $ok = 0;
> ++
> ++      while (my $line = <$fh>) {
> ++        chomp($line);
> ++
> ++        if ($ENV{TEST_VERBOSE}) {
> ++          print STDERR "# $line\n";
> ++        }
> ++
> ++        if ($line =~ /client signaled strict KEX support/) {
> ++          $ok = 1;
> ++          last;
> ++        }
> ++      }
> ++
> ++      close($fh);
> ++
> ++      $self->assert($ok, test_msg("Did not see expected 'strict KEX'
> TraceLog message"));
> ++
> ++    } else {
> ++      die("Can't read $setup->{log_file}: $!");
> ++    }
> ++  };
> ++  if ($@) {
> ++    $ex = $@;
> ++  }
> ++
> ++  test_cleanup($setup->{log_file}, $ex);
> ++}
> ++
> + sub ssh2_hostkey_rsa {
> +   my $self = shift;
> +   my $tmpdir = $self->{tmpdir};
> +--
> +2.25.1
> +
> diff --git a/meta-networking/recipes-daemons/proftpd/proftpd_1.3.7c.bb
> b/meta-networking/recipes-daemons/proftpd/proftpd_1.3.7c.bb
> index ec38fb54e1..036c01482a 100644
> --- a/meta-networking/recipes-daemons/proftpd/proftpd_1.3.7c.bb
> +++ b/meta-networking/recipes-daemons/proftpd/proftpd_1.3.7c.bb
> @@ -17,6 +17,7 @@ SRC_URI = "git://
> github.com/proftpd/proftpd.git;branch=${BRANCH};protocol=https
> <http://github.com/proftpd/proftpd.git;branch=$%7BBRANCH%7D;protocol=https>
>             file://proftpd.service \
>             file://CVE-2023-51713.patch \
>             file://CVE-2024-57392.patch \
> +           file://CVE-2023-48795.patch \
>             "
>
>  S = "${WORKDIR}/git"
> --
> 2.43.0
>
>