From 5c9ac36e581601cffdb28adf982a87bd861bbb0c Mon Sep 17 00:00:00 2001
From: Viktor Szakats <commit@vsz.me>
Date: Fri, 5 Jun 2026 02:45:53 +0200
Subject: [PATCH] libssh2: do not use deprecated macros when unavailable

To support building with `LIBSSH2_NO_DEPRECATED` macro defined, a future
libssh2 that may have dropped these macros.

Ref: https://github.com/libssh2/libssh2/pull/1977

Closes #21867
---
 lib/vssh/libssh2.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/lib/vssh/libssh2.c b/lib/vssh/libssh2.c
index 4a401edd2d..817e652e88 100644
--- a/lib/vssh/libssh2.c
+++ b/lib/vssh/libssh2.c
@@ -276,9 +276,11 @@ static enum curl_khtype convert_ssh2_keytype(int sshkeytype)
   case LIBSSH2_HOSTKEY_TYPE_RSA:
     keytype = CURLKHTYPE_RSA;
     break;
-  case LIBSSH2_HOSTKEY_TYPE_DSS:
+#ifdef LIBSSH2_HOSTKEY_TYPE_DSS
+  case LIBSSH2_HOSTKEY_TYPE_DSS:  /* deprecated upstream */
     keytype = CURLKHTYPE_DSS;
     break;
+#endif
 #ifdef LIBSSH2_HOSTKEY_TYPE_ECDSA_256
   case LIBSSH2_HOSTKEY_TYPE_ECDSA_256:
     keytype = CURLKHTYPE_ECDSA;
@@ -337,9 +339,11 @@ static CURLcode ssh_knownhost(struct Curl_easy *data,
       case LIBSSH2_HOSTKEY_TYPE_RSA:
         keybit = LIBSSH2_KNOWNHOST_KEY_SSHRSA;
         break;
-      case LIBSSH2_HOSTKEY_TYPE_DSS:
+#ifdef LIBSSH2_HOSTKEY_TYPE_DSS
+      case LIBSSH2_HOSTKEY_TYPE_DSS:  /* deprecated upstream */
         keybit = LIBSSH2_KNOWNHOST_KEY_SSHDSS;
         break;
+#endif
       case LIBSSH2_HOSTKEY_TYPE_ECDSA_256:
         keybit = LIBSSH2_KNOWNHOST_KEY_ECDSA_256;
         break;
@@ -618,7 +622,9 @@ static CURLcode ssh_force_knownhost_key_type(struct Curl_easy *data,
   static const char hostkey_method_ssh_ecdsa_256[] = "ecdsa-sha2-nistp256";
   static const char hostkey_method_ssh_rsa_all[] =
     "rsa-sha2-256,rsa-sha2-512,ssh-rsa";
+#ifdef LIBSSH2_KNOWNHOST_KEY_SSHDSS
   static const char hostkey_method_ssh_dss[] = "ssh-dss";
+#endif
   bool found = FALSE;
 
   if(sshc->kh &&
@@ -687,9 +693,11 @@ static CURLcode ssh_force_knownhost_key_type(struct Curl_easy *data,
       case LIBSSH2_KNOWNHOST_KEY_SSHRSA:
         hostkey_method = hostkey_method_ssh_rsa_all;
         break;
-      case LIBSSH2_KNOWNHOST_KEY_SSHDSS:
+#ifdef LIBSSH2_KNOWNHOST_KEY_SSHDSS
+      case LIBSSH2_KNOWNHOST_KEY_SSHDSS:  /* deprecated upstream */
         hostkey_method = hostkey_method_ssh_dss;
         break;
+#endif
       case LIBSSH2_KNOWNHOST_KEY_RSA1:
         failf(data, "Found host key type RSA1 which is not supported");
         return CURLE_SSH;