feat(smb): add SMB dialect selection and persistence (#445)

Support Auto, SMB1, SMB2, and SMB3 selection on Unix, bound negotiation to the selected dialect family, preserve legacy bookmarks as Auto, and document the new option. Windows keeps operating-system-managed negotiation.

Closes #439

Cargo.lock

@@ -2121,9 +2121,9 @@ dependencies = [
 
 [[package]]
 name = "git2"
-version = "0.20.4"
+version = "0.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b88256088d75a56f8ecfa070513a775dd9107f6530ef14919dac831af9cfe2b"
+checksum = "ddddbf932745a6be37109b6112d3ee09696106f848449069d3a57bba937ab82e"
 dependencies = [
  "bitflags 2.13.1",
  "libc",
@@ -3405,7 +3405,6 @@ checksum = "7f7c568b25d7489bc3fb2988ed69ab111d2944d2f5fec3d5c987fe545ea97b50"
 dependencies = [
  "cc",
  "libc",
- "libssh2-sys",
  "libz-sys",
  "openssl-sys",
  "pkg-config",
@@ -3426,20 +3425,6 @@ dependencies = [
  "libc",
 ]
 
-[[package]]
-name = "libssh2-sys"
-version = "0.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c04141a07bb0c0bc461cb657808764de571702a59bc5c726c400ac9a7625e3ab"
-dependencies = [
- "cc",
- "libc",
- "libz-sys",
- "openssl-sys",
- "pkg-config",
- "vcpkg",
-]
-
 [[package]]
 name = "libz-sys"
 version = "1.1.29"
@@ -4135,9 +4120,9 @@ checksum = "1e91099d4268b0e11973f036e885d652fb0b21fedcf69738c627f94db6a44f42"
 
 [[package]]
 name = "pavao"
-version = "0.2.16"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cca8302d5f1b5dc7a8dfb04e5ea7185b43571db5811e084746bf0aeb0d7b18f1"
+checksum = "6bf4bff78f032402eb6b89a72801f8d4b5ef57e79d33139f6e4fb214e823a854"
 dependencies = [
  "cfg_aliases",
  "lazy_static",
@@ -4149,9 +4134,9 @@ dependencies = [
 
 [[package]]
 name = "pavao-src"
-version = "4.22.0-4"
+version = "4.22.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "30b8c63418f1e7dfbb786268ae0927537b87d90b1211216c1ba50ce25d8d9495"
+checksum = "48289686720a0215553faa63f3211f0faa57c698287fb1ac41d3fbd423ed1f12"
 dependencies = [
  "cc",
  "git2",
@@ -4160,9 +4145,9 @@ dependencies = [
 
 [[package]]
 name = "pavao-sys"
-version = "0.2.16"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07b390d8c7372e94c7e0f7d92e36c98404634c554a52b1cb9ae030b4e7888cde"
+checksum = "8c6a44c550ef244c0a19f0a2201687af1853b0b9d1cfaa989a9312942c676adf"
 dependencies = [
  "cc",
  "libc",
@@ -4923,16 +4908,16 @@ dependencies = [
 
 [[package]]
 name = "remotefs-smb"
-version = "0.3.1"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c077c88aecf906b0267def951277dc4f6fd1f368edb73d333771a24c0b47970a"
+checksum = "c5e5b1fc4afd54e729393b3b44b537583c8e815d0c8e41483799001084e5fe96"
 dependencies = [
  "filetime",
  "libc",
  "log",
  "pavao",
  "remotefs",
- "windows-sys 0.59.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]

Cargo.toml

@@ -62,7 +62,7 @@ remotefs = "0.3"
 remotefs-aws-s3 = "0.4"
 remotefs-gcs = "0.1"
 remotefs-kube = "0.4"
-remotefs-smb = { version = "0.3", optional = true }
+remotefs-smb = { version = "0.4", optional = true }
 remotefs-ssh = { version = "0.9", default-features = false, features = ["russh"] }
 remotefs-webdav = "0.2"
 rpassword = "7"

docs/en-US/getting-started/connection-parameters.md

@@ -169,8 +169,28 @@ Authentication-form fields:
 - Password
 - Port (other systems only; default `445`)
 - Workgroup (other systems only)
+- SMB version (other systems only; default `Auto`)
 
-On Windows the port and workgroup fields are not used.
+On Windows the port, workgroup and SMB version fields are not used: the
+operating system manages SMB protocol negotiation.
+
+The SMB version field bounds the dialects offered during negotiation:
+
+| Selection | Dialects negotiated     |
+| --------- | ----------------------- |
+| Auto      | SMB 2.0.2 through 3.1.1 |
+| SMB1      | NT1 (CIFS) only         |
+| SMB2      | SMB 2.0.2 through 2.1   |
+| SMB3      | SMB 3.0 through 3.1.1   |
+
+`Auto` never negotiates SMB1. SMB1 is deprecated and insecure: select it only
+for isolated legacy devices that support nothing newer. A warning is shown in
+the form while SMB1 is selected.
+
+Bookmarks store the selection under the `dialect` key of the SMB table
+(`auto`, `smb1`, `smb2` or `smb3`). Bookmarks saved before this option existed
+have no `dialect` key and behave as `Auto`. The address syntax below does not
+carry a version; connections started from the command line use `Auto`.
 
 Windows address syntax:
 

docs/zh-CN/getting-started/connection-parameters.md

@@ -151,8 +151,22 @@ CLI 连接使用 ADC 和默认端点。如果需要自定义端点或服务账
 - 密码
 - 端口（仅其他系统；默认 `445`）
 - 工作组（仅其他系统）
+- SMB 版本（仅其他系统；默认 `Auto`）
 
-在 Windows 上，端口和工作组字段不会被使用。
+在 Windows 上，端口、工作组和 SMB 版本字段不会被使用：SMB 协议协商由操作系统管理。
+
+SMB 版本字段限定协商时可用的方言：
+
+| 选项 | 协商的方言         |
+| ---- | ------------------ |
+| Auto | SMB 2.0.2 至 3.1.1 |
+| SMB1 | 仅 NT1（CIFS）     |
+| SMB2 | SMB 2.0.2 至 2.1   |
+| SMB3 | SMB 3.0 至 3.1.1   |
+
+`Auto` 永远不会协商 SMB1。SMB1 已弃用且不安全：仅在无法支持更新协议的隔离旧设备上选择它。选择 SMB1 时，表单中会显示警告。
+
+书签使用 SMB 表中的 `dialect` 键保存所选项（`auto`、`smb1`、`smb2` 或 `smb3`）。在此选项出现之前保存的书签没有 `dialect` 键，其行为等同于 `Auto`。下方的地址语法不包含版本；从命令行发起的连接使用 `Auto`。
 
 Windows 地址语法：
 

src/config/bookmarks.rs

@@ -191,25 +191,25 @@ impl From<Bookmark> for FileTransferParams {
             }
             #[cfg(posix)]
             FileTransferProtocol::Smb => {
-                let params = TransferSmbParams::new(
+                let smb = bookmark.smb.unwrap_or_default();
-                    bookmark.address.unwrap_or_default(),
+                let params =
-                    bookmark.smb.clone().map(|x| x.share).unwrap_or_default(),
+                    TransferSmbParams::new(bookmark.address.unwrap_or_default(), smb.share)
-                )
                         .port(bookmark.port.unwrap_or(445))
                         .username(bookmark.username)
                         .password(bookmark.password)
-                .workgroup(bookmark.smb.and_then(|x| x.workgroup));
+                        .workgroup(smb.workgroup)
+                        .dialect(smb.dialect.unwrap_or_default());
 
                 Self::new(bookmark.protocol, ProtocolParams::Smb(params))
             }
             #[cfg(win)]
             FileTransferProtocol::Smb => {
-                let params = TransferSmbParams::new(
+                let smb = bookmark.smb.unwrap_or_default();
-                    bookmark.address.unwrap_or_default(),
+                let params =
-                    bookmark.smb.clone().map(|x| x.share).unwrap_or_default(),
+                    TransferSmbParams::new(bookmark.address.unwrap_or_default(), smb.share)
-                )
                         .username(bookmark.username)
-                .password(bookmark.password);
+                        .password(bookmark.password)
+                        .dialect(smb.dialect.unwrap_or_default());
 
                 Self::new(bookmark.protocol, ProtocolParams::Smb(params))
             }
@@ -254,7 +254,7 @@ mod tests {
     use pretty_assertions::assert_eq;
 
     use super::*;
-    use crate::filetransfer::params::DEFAULT_GCS_ENDPOINT;
+    use crate::filetransfer::params::{DEFAULT_GCS_ENDPOINT, SmbDialect};
 
     #[test]
     fn test_bookmarks_default() {
@@ -605,6 +605,7 @@ mod tests {
             smb: Some(SmbParams {
                 share: "test".to_string(),
                 workgroup: Some("testone".to_string()),
+                dialect: Some(SmbDialect::Smb2),
             }),
         };
 
@@ -625,6 +626,7 @@ mod tests {
         assert_eq!(smb_params.password.as_deref().unwrap(), "bar");
         assert_eq!(smb_params.username.as_deref().unwrap(), "foo");
         assert_eq!(smb_params.workgroup.as_deref().unwrap(), "testone");
+        assert_eq!(smb_params.dialect, SmbDialect::Smb2);
     }
 
     #[test]
@@ -644,6 +646,7 @@ mod tests {
             smb: Some(SmbParams {
                 share: "test".to_string(),
                 workgroup: None,
+                dialect: Some(SmbDialect::Smb2),
             }),
         };
 
@@ -660,5 +663,32 @@ mod tests {
         let smb_params = params.params.smb_params().unwrap();
         assert_eq!(smb_params.address.as_str(), "localhost");
         assert_eq!(smb_params.share.as_str(), "test");
+        assert_eq!(smb_params.dialect, SmbDialect::Smb2);
+    }
+
+    #[test]
+    fn should_default_dialect_when_bookmark_has_none() {
+        let bookmark: Bookmark = Bookmark {
+            protocol: FileTransferProtocol::Smb,
+            address: Some("localhost".to_string()),
+            port: Some(445),
+            username: None,
+            password: None,
+            remote_path: None,
+            local_path: None,
+            kube: None,
+            s3: None,
+            gcs: None,
+            smb: Some(SmbParams {
+                share: "test".to_string(),
+                workgroup: None,
+                dialect: None,
+            }),
+        };
+        let params = FileTransferParams::from(bookmark);
+        assert_eq!(
+            params.params.smb_params().unwrap().dialect,
+            SmbDialect::Auto
+        );
     }
 }

src/config/bookmarks/smb.rs

@@ -4,7 +4,7 @@
 
 use serde::{Deserialize, Serialize};
 
-use crate::filetransfer::params::SmbParams as TransferSmbParams;
+use crate::filetransfer::params::{SmbDialect, SmbParams as TransferSmbParams};
 
 /// Extra Connection parameters for SMB protocol
 #[derive(Clone, Deserialize, Serialize, Debug, PartialEq, Eq, Default)]
@@ -13,6 +13,9 @@ pub struct SmbParams {
     pub share: String,
     /// Optional SMB workgroup used on POSIX platforms.
     pub workgroup: Option<String>,
+    /// Requested SMB protocol family. `None` (older bookmarks) means `Auto`.
+    #[serde(default)]
+    pub dialect: Option<SmbDialect>,
 }
 
 #[cfg(posix)]
@@ -21,6 +24,7 @@ impl From<TransferSmbParams> for SmbParams {
         Self {
             share: params.share,
             workgroup: params.workgroup,
+            dialect: Some(params.dialect),
         }
     }
 }
@@ -31,6 +35,46 @@ impl From<TransferSmbParams> for SmbParams {
         Self {
             share: params.share,
             workgroup: None,
+            dialect: Some(params.dialect),
         }
     }
 }
+
+#[cfg(test)]
+mod test {
+    use pretty_assertions::assert_eq;
+
+    use super::*;
+
+    #[test]
+    fn should_deserialize_missing_dialect_as_none() {
+        let params: SmbParams = toml::from_str("share = \"temp\"").unwrap();
+        assert_eq!(params.share.as_str(), "temp");
+        assert_eq!(params.dialect, None);
+    }
+
+    #[test]
+    fn should_deserialize_dialect() {
+        let params: SmbParams = toml::from_str("share = \"temp\"\ndialect = \"smb1\"").unwrap();
+        assert_eq!(params.dialect, Some(SmbDialect::Smb1));
+    }
+
+    #[test]
+    fn should_round_trip_dialect() {
+        let params = SmbParams {
+            share: "temp".to_string(),
+            workgroup: None,
+            dialect: Some(SmbDialect::Smb2),
+        };
+        let toml_str = toml::to_string(&params).unwrap();
+        let decoded: SmbParams = toml::from_str(&toml_str).unwrap();
+        assert_eq!(decoded, params);
+    }
+
+    #[test]
+    fn should_convert_transfer_params_with_dialect() {
+        let transfer = TransferSmbParams::new("localhost", "temp").dialect(SmbDialect::Smb3);
+        let params = SmbParams::from(transfer);
+        assert_eq!(params.dialect, Some(SmbDialect::Smb3));
+    }
+}

src/config/serialization.rs

@@ -118,7 +118,8 @@ mod tests {
     use crate::config::bookmarks::{Bookmark, KubeParams, S3Params, SmbParams, UserHosts};
     use crate::config::params::UserConfig;
     use crate::config::themes::Theme;
-    use crate::filetransfer::FileTransferProtocol;
+    use crate::filetransfer::params::SmbDialect;
+    use crate::filetransfer::{FileTransferParams, FileTransferProtocol};
     use crate::utils::test_helpers::create_file_ioers;
 
     #[test]
@@ -445,6 +446,7 @@ mod tests {
         assert_eq!(smb.share.as_str(), "temp");
         #[cfg(posix)]
         assert_eq!(smb.workgroup.as_deref().unwrap(), "test");
+        assert_eq!(smb.dialect, None);
     }
 
     #[test]
@@ -491,6 +493,66 @@ mod tests {
         assert_eq!(gcs.service_account_key, None);
     }
 
+    #[test]
+    fn should_deserialize_legacy_smb_bookmark_without_dialect() {
+        let toml_file = create_good_toml_bookmarks();
+        toml_file.as_file().sync_all().unwrap();
+        toml_file.as_file().rewind().unwrap();
+
+        let hosts: UserHosts = deserialize(Box::new(toml_file)).unwrap();
+        let host = hosts.bookmarks.get("smb").unwrap();
+        let smb = host.smb.as_ref().unwrap();
+        assert_eq!(smb.share.as_str(), "temp");
+        assert_eq!(smb.dialect, None);
+
+        // Legacy bookmarks resolve to secure Auto at runtime.
+        let params = FileTransferParams::from(host.clone());
+        assert_eq!(
+            params.params.smb_params().unwrap().dialect,
+            SmbDialect::Auto
+        );
+    }
+
+    #[test]
+    fn should_deserialize_smb_bookmark_with_dialect() {
+        let toml_file = create_smb_dialect_toml_bookmark();
+        toml_file.as_file().sync_all().unwrap();
+        toml_file.as_file().rewind().unwrap();
+
+        let hosts: UserHosts = deserialize(Box::new(toml_file)).unwrap();
+        let host = hosts.bookmarks.get("smb-dialect").unwrap();
+        let smb = host.smb.as_ref().unwrap();
+        assert_eq!(smb.dialect, Some(SmbDialect::Smb2));
+
+        let params = FileTransferParams::from(host.clone());
+        assert_eq!(
+            params.params.smb_params().unwrap().dialect,
+            SmbDialect::Smb2
+        );
+    }
+
+    #[test]
+    fn should_reserialize_legacy_smb_bookmark_and_reload() {
+        let toml_file = create_good_toml_bookmarks();
+        toml_file.as_file().sync_all().unwrap();
+        toml_file.as_file().rewind().unwrap();
+        let hosts: UserHosts = deserialize(Box::new(toml_file)).unwrap();
+
+        let output_file = tempfile::NamedTempFile::new().unwrap();
+        let output_path = output_file.path().to_path_buf();
+        serialize(
+            &hosts,
+            Box::new(std::fs::File::create(&output_path).unwrap()),
+        )
+        .unwrap();
+
+        let reloaded: UserHosts =
+            deserialize(Box::new(std::fs::File::open(&output_path).unwrap())).unwrap();
+        let smb = reloaded.bookmarks.get("smb").unwrap().smb.as_ref().unwrap();
+        assert_eq!(smb.share.as_str(), "temp");
+        assert_eq!(smb.dialect, None);
+    }
+
     #[test]
     fn should_serialize_gcs_bookmark_fields() {
         let toml_file = create_good_toml_bookmarks();
@@ -630,6 +692,7 @@ mod tests {
         let smb_params: Option<SmbParams> = Some(SmbParams {
             share: "test".to_string(),
             workgroup: None,
+            dialect: None,
         });
         bookmarks.insert(
             String::from("smb"),
@@ -789,6 +852,27 @@ mod tests {
         tmpfile
     }
 
+    fn create_smb_dialect_toml_bookmark() -> tempfile::NamedTempFile {
+        let mut tmpfile: tempfile::NamedTempFile = tempfile::NamedTempFile::new().unwrap();
+        let file_content: &str = r#"
+        [bookmarks.smb-dialect]
+        protocol = "SMB"
+        address = "localhost"
+        port = 445
+        username = "test"
+        password = "test"
+
+        [bookmarks.smb-dialect.smb]
+        share = "temp"
+        workgroup = "test"
+        dialect = "smb2"
+
+        [recents]
+        "#;
+        tmpfile.write_all(file_content.as_bytes()).unwrap();
+        tmpfile
+    }
+
     fn create_v14_pod_bookmark() -> tempfile::NamedTempFile {
         let mut tmpfile: tempfile::NamedTempFile = tempfile::NamedTempFile::new().unwrap();
         let file_content: &str = r#"

src/filetransfer/params.rs

@@ -13,7 +13,7 @@ use std::path::{Path, PathBuf};
 pub use self::aws_s3::AwsS3Params;
 pub use self::google_cloud_storage::{DEFAULT_GCS_ENDPOINT, GoogleCloudStorageParams};
 pub use self::kube::KubeProtocolParams;
-pub use self::smb::SmbParams;
+pub use self::smb::{SmbDialect, SmbParams};
 pub use self::webdav::WebDAVProtocolParams;
 use super::FileTransferProtocol;
 

src/filetransfer/params/smb.rs

@@ -3,6 +3,26 @@
 //! Defines the runtime connection parameters used to build SMB remote
 //! filesystem clients.
 
+use serde::{Deserialize, Serialize};
+
+/// SMB protocol family requested for a connection.
+///
+/// Each family maps to inclusive dialect bounds when the Unix client is built.
+/// `Auto` negotiates SMB2 or SMB3 and never falls back to SMB1.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum SmbDialect {
+    /// Negotiate SMB 2.0.2 through SMB 3.1.1.
+    #[default]
+    Auto,
+    /// Force the deprecated NT1 (CIFS) dialect.
+    Smb1,
+    /// Negotiate SMB 2.0.2 through SMB 2.1.
+    Smb2,
+    /// Negotiate SMB 3.0 through SMB 3.1.1.
+    Smb3,
+}
+
 /// Connection parameters for SMB protocol
 #[derive(Debug, Clone)]
 pub struct SmbParams {
@@ -20,6 +40,8 @@ pub struct SmbParams {
     #[cfg(posix)]
     /// Optional workgroup used on POSIX platforms.
     pub workgroup: Option<String>,
+    /// Requested SMB protocol family. Enforced on POSIX platforms only.
+    pub dialect: SmbDialect,
 }
 
 // -- SMB params
@@ -36,6 +58,7 @@ impl SmbParams {
             password: None,
             #[cfg(posix)]
             workgroup: None,
+            dialect: SmbDialect::default(),
         }
     }
 
@@ -61,6 +84,12 @@ impl SmbParams {
         self
     }
 
+    /// Sets the SMB protocol family to request.
+    pub fn dialect(mut self, dialect: SmbDialect) -> Self {
+        self.dialect = dialect;
+        self
+    }
+
     /// Returns whether a password is supposed to be required for this protocol params.
     /// The result true is returned ONLY if the supposed secret is MISSING!!!
     pub fn password_missing(&self) -> bool {
@@ -82,7 +111,8 @@ mod test {
 
     use pretty_assertions::assert_eq;
 
-    use super::*;
+    use super::SmbParams;
+    use crate::filetransfer::params::SmbDialect;
 
     #[test]
     fn should_init_smb_params() {
@@ -118,6 +148,67 @@ mod test {
         assert_eq!(params.workgroup.as_deref().unwrap(), "baz");
     }
 
+    #[test]
+    fn should_default_dialect_to_auto() {
+        assert_eq!(SmbDialect::default(), SmbDialect::Auto);
+        let params = SmbParams::new("localhost", "temp");
+        assert_eq!(params.dialect, SmbDialect::Auto);
+    }
+
+    #[test]
+    fn should_set_dialect() {
+        let params = SmbParams::new("localhost", "temp").dialect(SmbDialect::Smb1);
+        assert_eq!(params.dialect, SmbDialect::Smb1);
+    }
+
+    #[test]
+    fn should_serialize_dialect_lowercase() {
+        assert_eq!(
+            toml::to_string(&Wrapper {
+                dialect: SmbDialect::Auto,
+            })
+            .unwrap()
+            .trim(),
+            "dialect = \"auto\""
+        );
+        assert_eq!(
+            toml::to_string(&Wrapper {
+                dialect: SmbDialect::Smb1,
+            })
+            .unwrap()
+            .trim(),
+            "dialect = \"smb1\""
+        );
+        assert_eq!(
+            toml::to_string(&Wrapper {
+                dialect: SmbDialect::Smb2,
+            })
+            .unwrap()
+            .trim(),
+            "dialect = \"smb2\""
+        );
+        assert_eq!(
+            toml::to_string(&Wrapper {
+                dialect: SmbDialect::Smb3,
+            })
+            .unwrap()
+            .trim(),
+            "dialect = \"smb3\""
+        );
+    }
+
+    #[test]
+    fn should_deserialize_dialect_lowercase() {
+        let w: Wrapper = toml::from_str("dialect = \"smb3\"").unwrap();
+        assert_eq!(w.dialect, SmbDialect::Smb3);
+        assert!(toml::from_str::<Wrapper>("dialect = \"SMB3\"").is_err());
+    }
+
+    #[derive(serde::Serialize, serde::Deserialize)]
+    struct Wrapper {
+        dialect: SmbDialect,
+    }
+
     #[test]
     #[cfg(win)]
     fn should_init_smb_params_with_optionals() {

src/filetransfer/remotefs_builder.rs

@@ -11,16 +11,18 @@ use remotefs_ftp::FtpFs;
 use remotefs_gcs::credentials::service_account;
 use remotefs_gcs::{GoogleCloudStorageCredentials, GoogleCloudStorageFs};
 use remotefs_kube::KubeMultiPodFs as KubeFs;
-#[cfg(smb_unix)]
-use remotefs_smb::SmbOptions;
 #[cfg(smb)]
 use remotefs_smb::{SmbCredentials, SmbFs};
+#[cfg(smb_unix)]
+use remotefs_smb::{SmbDialect as RemoteSmbDialect, SmbOptions};
 use remotefs_ssh::{
     NoCheckServerKey, RusshSession as SshSession, ScpFs, SftpFs, SshAgentIdentity,
     SshConfigParseRule, SshOpts,
 };
 use remotefs_webdav::WebDAVFs;
 
+#[cfg(smb_unix)]
+use super::params::SmbDialect;
 #[cfg(not(smb))]
 use super::params::{AwsS3Params, GenericProtocolParams, GoogleCloudStorageParams};
 #[cfg(smb)]
@@ -189,6 +191,17 @@ impl RemoteFsBuilder {
         Ok(SftpFs::russh(opts, rt))
     }
 
+    /// Maps the user-facing SMB family to inclusive remotefs dialect bounds.
+    #[cfg(smb_unix)]
+    fn smb_dialect_bounds(dialect: SmbDialect) -> (RemoteSmbDialect, RemoteSmbDialect) {
+        match dialect {
+            SmbDialect::Auto => (RemoteSmbDialect::Smb202, RemoteSmbDialect::Smb311),
+            SmbDialect::Smb1 => (RemoteSmbDialect::Nt1, RemoteSmbDialect::Nt1),
+            SmbDialect::Smb2 => (RemoteSmbDialect::Smb202, RemoteSmbDialect::Smb210),
+            SmbDialect::Smb3 => (RemoteSmbDialect::Smb300, RemoteSmbDialect::Smb311),
+        }
+    }
+
     #[cfg(smb_unix)]
     fn smb_client(params: SmbParams) -> Result<SmbFs, String> {
         let mut credentials = SmbCredentials::default()
@@ -205,11 +218,14 @@ impl RemoteFsBuilder {
             credentials = credentials.workgroup(workgroup);
         }
 
-        SmbFs::try_new(
+        let (min_dialect, max_dialect) = Self::smb_dialect_bounds(params.dialect);
+        SmbFs::try_new_with_dialect(
             credentials,
             SmbOptions::default()
                 .one_share_per_server(true)
                 .case_sensitive(false),
+            min_dialect,
+            max_dialect,
         )
         .map_err(|e| {
             error!("Invalid params for protocol SMB: {e}");
@@ -228,6 +244,7 @@ impl RemoteFsBuilder {
             credentials = credentials.password(password);
         }
 
+        // Dialect is OS-managed on Windows.
         Ok(SmbFs::new(credentials))
     }
 
@@ -284,6 +301,8 @@ mod test {
 
     use std::path::{Path, PathBuf};
 
+    #[cfg(smb)]
+    use serial_test::serial;
     use tempfile::TempDir;
 
     use super::*;
@@ -417,12 +436,50 @@ mod test {
 
     #[test]
     #[cfg(smb)]
+    #[serial]
     fn should_build_smb_fs() {
         let params = ProtocolParams::Smb(SmbParams::new("localhost", "share"));
         let config_client = get_config_client();
         assert!(RemoteFsBuilder::build(FileTransferProtocol::Smb, params, &config_client).is_ok());
     }
 
+    #[test]
+    #[cfg(smb_unix)]
+    fn should_map_smb_dialect_to_bounds() {
+        use remotefs_smb::SmbDialect as RemoteSmbDialect;
+
+        use crate::filetransfer::params::SmbDialect;
+
+        assert_eq!(
+            RemoteFsBuilder::smb_dialect_bounds(SmbDialect::Auto),
+            (RemoteSmbDialect::Smb202, RemoteSmbDialect::Smb311)
+        );
+        assert_eq!(
+            RemoteFsBuilder::smb_dialect_bounds(SmbDialect::Smb1),
+            (RemoteSmbDialect::Nt1, RemoteSmbDialect::Nt1)
+        );
+        assert_eq!(
+            RemoteFsBuilder::smb_dialect_bounds(SmbDialect::Smb2),
+            (RemoteSmbDialect::Smb202, RemoteSmbDialect::Smb210)
+        );
+        assert_eq!(
+            RemoteFsBuilder::smb_dialect_bounds(SmbDialect::Smb3),
+            (RemoteSmbDialect::Smb300, RemoteSmbDialect::Smb311)
+        );
+    }
+
+    #[test]
+    #[cfg(smb)]
+    #[serial]
+    fn should_build_smb_fs_with_dialect() {
+        use crate::filetransfer::params::SmbDialect;
+
+        let params =
+            ProtocolParams::Smb(SmbParams::new("localhost", "share").dialect(SmbDialect::Smb1));
+        let config_client = get_config_client();
+        assert!(RemoteFsBuilder::build(FileTransferProtocol::Smb, params, &config_client).is_ok());
+    }
+
     #[test]
     fn should_not_build_fs() {
         let params = ProtocolParams::Generic(

src/ui/activities/auth.rs

@@ -101,6 +101,10 @@ pub enum AuthFormId {
     SmbShare,
     #[cfg(posix)]
     SmbWorkgroup,
+    #[cfg(posix)]
+    SmbDialect,
+    #[cfg(posix)]
+    SmbDialectWarning,
     Username,
     WebDAVUri,
 }
@@ -209,6 +213,10 @@ pub enum UiAuthFormMsg {
     SmbWorkgroupDown,
     #[cfg(posix)]
     SmbWorkgroupUp,
+    #[cfg(posix)]
+    SmbDialectBlurDown,
+    #[cfg(posix)]
+    SmbDialectBlurUp,
     UsernameBlurDown,
     UsernameBlurUp,
     WebDAVUriBlurDown,

src/ui/activities/auth/bookmarks.rs

@@ -315,6 +315,8 @@ impl AuthActivity {
         self.mount_smb_share(form_tab, &params.share);
         #[cfg(posix)]
         self.mount_smb_workgroup(form_tab, params.workgroup.as_deref().unwrap_or(""));
+        #[cfg(posix)]
+        self.mount_smb_dialect(form_tab, params.dialect);
     }
 
     fn load_bookmark_webdav_into_gui(&mut self, form_tab: FormTab, params: WebDAVProtocolParams) {

src/ui/activities/auth/components.rs

@@ -13,8 +13,6 @@ pub use bookmarks::{
     BookmarkName, BookmarkSavePassword, BookmarksList, DeleteBookmarkPopup, DeleteRecentPopup,
     RecentsList,
 };
-#[cfg(posix)]
-pub use form::InputSmbWorkgroup;
 pub use form::{
     HostBridgeProtocolRadio, InputAddress, InputGcsBucket, InputGcsEndpoint,
     InputGcsServiceAccountKey, InputKubeClientCert, InputKubeClientKey, InputKubeClusterUrl,
@@ -23,6 +21,8 @@ pub use form::{
     InputS3Region, InputS3SecretAccessKey, InputS3SecurityToken, InputS3SessionToken,
     InputSmbShare, InputUsername, InputWebDAVUri, RadioS3NewPathStyle, RemoteProtocolRadio,
 };
+#[cfg(posix)]
+pub use form::{InputSmbWorkgroup, RadioSmbDialect, SmbDialectWarning};
 pub use popup::{
     ErrorPopup, InfoPopup, InstallUpdatePopup, Keybindings, QuitPopup, ReleaseNotes, WaitPopup,
     WindowSizeError,

src/ui/activities/auth/components/form.rs

@@ -54,7 +54,7 @@ pub use s3::{
 };
 pub use smb::InputSmbShare;
 #[cfg(posix)]
-pub use smb::InputSmbWorkgroup;
+pub use smb::{InputSmbWorkgroup, RadioSmbDialect, SmbDialectWarning};
 pub use webdav::InputWebDAVUri;
 
 fn handle_input_ev(

src/ui/activities/auth/components/form/smb.rs

@@ -1,7 +1,13 @@
+#[cfg(posix)]
+use tui_realm_stdlib::components::Span;
 use tuirealm::component::{AppComponent, Component};
 use tuirealm::event::NoUserEvent;
+#[cfg(posix)]
+use tuirealm::props::SpanStatic;
 
 use super::*;
+#[cfg(posix)]
+use crate::filetransfer::params::SmbDialect;
 
 #[derive(Component)]
 pub struct InputSmbShare {
@@ -85,3 +91,163 @@ impl AppComponent<Msg, NoUserEvent> for InputSmbWorkgroup {
         handle_input_ev(self, ev, on_key_down, on_key_up, form_tab)
     }
 }
+
+#[cfg(all(test, posix))]
+mod test {
+    use pretty_assertions::assert_eq;
+
+    use super::*;
+    use crate::filetransfer::params::SmbDialect;
+
+    #[test]
+    fn should_map_radio_options_to_dialect() {
+        assert_eq!(RadioSmbDialect::opt_to_dialect(0), SmbDialect::Auto);
+        assert_eq!(RadioSmbDialect::opt_to_dialect(1), SmbDialect::Smb1);
+        assert_eq!(RadioSmbDialect::opt_to_dialect(2), SmbDialect::Smb2);
+        assert_eq!(RadioSmbDialect::opt_to_dialect(3), SmbDialect::Smb3);
+        assert_eq!(RadioSmbDialect::opt_to_dialect(99), SmbDialect::Auto);
+    }
+
+    #[test]
+    fn should_map_dialect_to_radio_options() {
+        for dialect in [
+            SmbDialect::Auto,
+            SmbDialect::Smb1,
+            SmbDialect::Smb2,
+            SmbDialect::Smb3,
+        ] {
+            let opt = RadioSmbDialect::dialect_to_opt(dialect);
+            assert_eq!(RadioSmbDialect::opt_to_dialect(opt), dialect);
+        }
+    }
+}
+
+#[cfg(posix)]
+const RADIO_SMB_DIALECT_AUTO: usize = 0;
+#[cfg(posix)]
+const RADIO_SMB_DIALECT_SMB1: usize = 1;
+#[cfg(posix)]
+const RADIO_SMB_DIALECT_SMB2: usize = 2;
+#[cfg(posix)]
+const RADIO_SMB_DIALECT_SMB3: usize = 3;
+
+/// Radio to select the SMB protocol family.
+#[cfg(posix)]
+#[derive(Component)]
+pub struct RadioSmbDialect {
+    component: Radio,
+    form_tab: FormTab,
+}
+
+#[cfg(posix)]
+impl RadioSmbDialect {
+    pub fn new(dialect: SmbDialect, form_tab: FormTab, color: Color) -> Self {
+        Self {
+            component: Radio::default()
+                .highlight_style(
+                    Style::default()
+                        .fg(color)
+                        .add_modifier(TextModifiers::REVERSED),
+                )
+                .borders(
+                    Borders::default()
+                        .color(color)
+                        .modifiers(BorderType::Rounded),
+                )
+                .choices(["Auto", "SMB1 (insecure)", "SMB2", "SMB3"])
+                .rewind(true)
+                .title(Title::from("SMB version").alignment(HorizontalAlignment::Left))
+                .value(Self::dialect_to_opt(dialect)),
+            form_tab,
+        }
+    }
+
+    /// Converts the radio choice index to a dialect. Unknown indexes map to `Auto`.
+    pub fn opt_to_dialect(opt: usize) -> SmbDialect {
+        match opt {
+            RADIO_SMB_DIALECT_SMB1 => SmbDialect::Smb1,
+            RADIO_SMB_DIALECT_SMB2 => SmbDialect::Smb2,
+            RADIO_SMB_DIALECT_SMB3 => SmbDialect::Smb3,
+            _ => SmbDialect::Auto,
+        }
+    }
+
+    fn dialect_to_opt(dialect: SmbDialect) -> usize {
+        match dialect {
+            SmbDialect::Auto => RADIO_SMB_DIALECT_AUTO,
+            SmbDialect::Smb1 => RADIO_SMB_DIALECT_SMB1,
+            SmbDialect::Smb2 => RADIO_SMB_DIALECT_SMB2,
+            SmbDialect::Smb3 => RADIO_SMB_DIALECT_SMB3,
+        }
+    }
+}
+
+#[cfg(posix)]
+impl AppComponent<Msg, NoUserEvent> for RadioSmbDialect {
+    fn on(&mut self, ev: &Event<NoUserEvent>) -> Option<Msg> {
+        match ev {
+            Event::Keyboard(KeyEvent {
+                code: Key::Left, ..
+            }) => {
+                self.perform(Cmd::Move(Direction::Left));
+                Some(Msg::None)
+            }
+            Event::Keyboard(KeyEvent {
+                code: Key::Right, ..
+            }) => {
+                self.perform(Cmd::Move(Direction::Right));
+                Some(Msg::None)
+            }
+            Event::Keyboard(KeyEvent {
+                code: Key::Enter, ..
+            }) => Some(Msg::Form(FormMsg::Connect)),
+            Event::Keyboard(KeyEvent {
+                code: Key::Down, ..
+            }) => Some(if self.form_tab == FormTab::Remote {
+                Msg::Ui(UiMsg::Remote(UiAuthFormMsg::SmbDialectBlurDown))
+            } else {
+                Msg::Ui(UiMsg::HostBridge(UiAuthFormMsg::SmbDialectBlurDown))
+            }),
+            Event::Keyboard(KeyEvent { code: Key::Up, .. }) => {
+                Some(if self.form_tab == FormTab::Remote {
+                    Msg::Ui(UiMsg::Remote(UiAuthFormMsg::SmbDialectBlurUp))
+                } else {
+                    Msg::Ui(UiMsg::HostBridge(UiAuthFormMsg::SmbDialectBlurUp))
+                })
+            }
+            Event::Keyboard(KeyEvent { code: Key::Tab, .. }) => {
+                Some(if self.form_tab == FormTab::Remote {
+                    Msg::Ui(UiMsg::Remote(UiAuthFormMsg::ParamsFormBlur))
+                } else {
+                    Msg::Ui(UiMsg::HostBridge(UiAuthFormMsg::ParamsFormBlur))
+                })
+            }
+            _ => None,
+        }
+    }
+}
+
+/// One-line warning shown above the dialect radio while SMB1 is selected.
+#[cfg(posix)]
+#[derive(Component)]
+pub struct SmbDialectWarning {
+    component: Span,
+}
+
+#[cfg(posix)]
+impl SmbDialectWarning {
+    pub fn new(color: Color) -> Self {
+        Self {
+            component: Span::default().foreground(color).spans([SpanStatic::from(
+                "Warning: SMB1 is deprecated and insecure. Use it only for isolated legacy devices.",
+            )]),
+        }
+    }
+}
+
+#[cfg(posix)]
+impl AppComponent<Msg, NoUserEvent> for SmbDialectWarning {
+    fn on(&mut self, _ev: &Event<NoUserEvent>) -> Option<Msg> {
+        None
+    }
+}

src/ui/activities/auth/update.rs

@@ -358,7 +358,7 @@ impl AuthActivity {
                     InputMask::Localhost => unreachable!(),
                     InputMask::Generic => Id::HostBridge(AuthFormId::Password),
                     #[cfg(posix)]
-                    InputMask::Smb => Id::HostBridge(AuthFormId::SmbWorkgroup),
+                    InputMask::Smb => Id::HostBridge(AuthFormId::SmbDialect),
                     #[cfg(win)]
                     InputMask::Smb => Id::HostBridge(AuthFormId::Password),
                     InputMask::Kube => Id::HostBridge(AuthFormId::KubeClientKey),
@@ -483,12 +483,20 @@ impl AuthActivity {
             }
             #[cfg(posix)]
             UiAuthFormMsg::SmbWorkgroupDown => {
-                self.activate_component(Id::HostBridge(AuthFormId::RemoteDirectory))
+                self.activate_component(Id::HostBridge(AuthFormId::SmbDialect))
             }
             #[cfg(posix)]
             UiAuthFormMsg::SmbWorkgroupUp => {
                 self.activate_component(Id::HostBridge(AuthFormId::Password))
             }
+            #[cfg(posix)]
+            UiAuthFormMsg::SmbDialectBlurDown => {
+                self.activate_component(Id::HostBridge(AuthFormId::RemoteDirectory))
+            }
+            #[cfg(posix)]
+            UiAuthFormMsg::SmbDialectBlurUp => {
+                self.activate_component(Id::HostBridge(AuthFormId::SmbWorkgroup))
+            }
             UiAuthFormMsg::UsernameBlurDown => {
                 self.activate_component(Id::HostBridge(AuthFormId::Password))
             }
@@ -601,7 +609,7 @@ impl AuthActivity {
                     InputMask::Localhost => unreachable!(),
                     InputMask::Generic => Id::Remote(AuthFormId::Password),
                     #[cfg(posix)]
-                    InputMask::Smb => Id::Remote(AuthFormId::SmbWorkgroup),
+                    InputMask::Smb => Id::Remote(AuthFormId::SmbDialect),
                     #[cfg(win)]
                     InputMask::Smb => Id::Remote(AuthFormId::Password),
                     InputMask::Kube => Id::Remote(AuthFormId::KubeClientKey),
@@ -726,12 +734,20 @@ impl AuthActivity {
             }
             #[cfg(posix)]
             UiAuthFormMsg::SmbWorkgroupDown => {
-                self.activate_component(Id::Remote(AuthFormId::RemoteDirectory))
+                self.activate_component(Id::Remote(AuthFormId::SmbDialect))
             }
             #[cfg(posix)]
             UiAuthFormMsg::SmbWorkgroupUp => {
                 self.activate_component(Id::Remote(AuthFormId::Password))
             }
+            #[cfg(posix)]
+            UiAuthFormMsg::SmbDialectBlurDown => {
+                self.activate_component(Id::Remote(AuthFormId::RemoteDirectory))
+            }
+            #[cfg(posix)]
+            UiAuthFormMsg::SmbDialectBlurUp => {
+                self.activate_component(Id::Remote(AuthFormId::SmbWorkgroup))
+            }
             UiAuthFormMsg::UsernameBlurDown => {
                 self.activate_component(Id::Remote(AuthFormId::Password))
             }

src/ui/activities/auth/view.rs

@@ -3,7 +3,7 @@
 //! `auth_activity` is the module which implements the authentication activity
 
 use tuirealm::props::Color;
-use tuirealm::ratatui::layout::{Constraint, Direction, Layout};
+use tuirealm::ratatui::layout::{Constraint, Direction, Layout, Rect};
 use tuirealm::ratatui::widgets::Clear;
 use tuirealm::terminal::TerminalAdapter;
 
@@ -12,6 +12,8 @@ use super::{
     InputMask, components,
 };
 use crate::filetransfer::params::DEFAULT_GCS_ENDPOINT;
+#[cfg(posix)]
+use crate::filetransfer::params::SmbDialect;
 use crate::utils::ui::{Popup, Size};
 
 #[path = "view/mounting.rs"]
@@ -73,6 +75,10 @@ impl AuthActivity {
         self.mount_smb_share(FormTab::HostBridge, "");
         #[cfg(posix)]
         self.mount_smb_workgroup(FormTab::HostBridge, "");
+        #[cfg(posix)]
+        self.mount_smb_dialect(FormTab::HostBridge, SmbDialect::default());
+        #[cfg(posix)]
+        self.mount_smb_dialect_warning(FormTab::HostBridge);
         self.mount_webdav_uri(FormTab::HostBridge, "");
 
         let remote_default_protocol = self.context().config().get_default_protocol();
@@ -107,6 +113,10 @@ impl AuthActivity {
         self.mount_smb_share(FormTab::Remote, "");
         #[cfg(posix)]
         self.mount_smb_workgroup(FormTab::Remote, "");
+        #[cfg(posix)]
+        self.mount_smb_dialect(FormTab::Remote, SmbDialect::default());
+        #[cfg(posix)]
+        self.mount_smb_dialect_warning(FormTab::Remote);
         self.mount_webdav_uri(FormTab::Remote, "");
 
         if let Some(version) = self
@@ -247,8 +257,10 @@ impl AuthActivity {
         f: &mut tuirealm::ratatui::Frame<'_>,
         area: tuirealm::ratatui::layout::Rect,
     ) {
+        let input_mask_size = Self::input_mask_size(self.host_bridge_input_mask());
+        let input_mask = self.host_bridge_input_mask();
         let protocol_and_mask_chunks = Layout::default()
-            .constraints([Constraint::Length(3), Constraint::Length(12)].as_ref())
+            .constraints([Constraint::Length(3), Constraint::Length(input_mask_size)].as_ref())
             .direction(Direction::Vertical)
             .split(area);
 
@@ -258,36 +270,25 @@ impl AuthActivity {
             protocol_and_mask_chunks[0],
         );
 
-        let input_mask = Layout::default()
+        let view_ids = match input_mask {
-            .constraints(
+            InputMask::AwsS3 => self.get_host_bridge_s3_view(),
-                [
+            InputMask::Gcs => self.get_host_bridge_gcs_view(),
-                    Constraint::Length(3),
+            InputMask::Generic => self.get_host_bridge_generic_params_view(),
-                    Constraint::Length(3),
+            InputMask::Kube => self.get_host_bridge_kube_view(),
-                    Constraint::Length(3),
-                    Constraint::Length(3),
-                ]
-                .as_ref(),
-            )
-            .direction(Direction::Vertical)
-            .split(protocol_and_mask_chunks[1]);
-        match self.host_bridge_input_mask() {
-            InputMask::AwsS3 => self.render_view_ids(f, input_mask, self.get_host_bridge_s3_view()),
-            InputMask::Gcs => self.render_view_ids(f, input_mask, self.get_host_bridge_gcs_view()),
-            InputMask::Generic => {
-                self.render_view_ids(f, input_mask, self.get_host_bridge_generic_params_view())
-            }
-            InputMask::Kube => {
-                self.render_view_ids(f, input_mask, self.get_host_bridge_kube_view())
-            }
             InputMask::Localhost => {
                 let view_ids = self.get_host_bridge_localhost_view();
-                self.app.view(&view_ids[0], f, input_mask[0]);
+                self.app.view(&view_ids[0], f, protocol_and_mask_chunks[1]);
-            }
+                return;
-            InputMask::Smb => self.render_view_ids(f, input_mask, self.get_host_bridge_smb_view()),
-            InputMask::WebDAV => {
-                self.render_view_ids(f, input_mask, self.get_host_bridge_webdav_view())
-            }
             }
+            InputMask::Smb => self.get_host_bridge_smb_view(),
+            InputMask::WebDAV => self.get_host_bridge_webdav_view(),
+        };
+        self.render_form_rows(
+            f,
+            protocol_and_mask_chunks[1],
+            FormTab::HostBridge,
+            view_ids,
+        );
     }
 
     fn render_remote_input_mask(
@@ -295,8 +296,10 @@ impl AuthActivity {
         f: &mut tuirealm::ratatui::Frame<'_>,
         area: tuirealm::ratatui::layout::Rect,
     ) {
+        let input_mask_size = Self::input_mask_size(self.remote_input_mask());
+        let input_mask = self.remote_input_mask();
         let protocol_and_mask_chunks = Layout::default()
-            .constraints([Constraint::Length(3), Constraint::Length(12)].as_ref())
+            .constraints([Constraint::Length(3), Constraint::Length(input_mask_size)].as_ref())
             .direction(Direction::Vertical)
             .split(area);
 
@@ -306,40 +309,135 @@ impl AuthActivity {
             protocol_and_mask_chunks[0],
         );
 
-        let input_mask = Layout::default()
+        let view_ids = match input_mask {
-            .constraints(
+            InputMask::AwsS3 => self.get_remote_s3_view(),
-                [
+            InputMask::Gcs => self.get_remote_gcs_view(),
-                    Constraint::Length(3),
+            InputMask::Generic => self.get_remote_generic_params_view(),
-                    Constraint::Length(3),
+            InputMask::Kube => self.get_remote_kube_view(),
-                    Constraint::Length(3),
-                    Constraint::Length(3),
-                ]
-                .as_ref(),
-            )
-            .direction(Direction::Vertical)
-            .split(protocol_and_mask_chunks[1]);
-        match self.remote_input_mask() {
-            InputMask::AwsS3 => self.render_view_ids(f, input_mask, self.get_remote_s3_view()),
-            InputMask::Gcs => self.render_view_ids(f, input_mask, self.get_remote_gcs_view()),
-            InputMask::Generic => {
-                self.render_view_ids(f, input_mask, self.get_remote_generic_params_view())
-            }
-            InputMask::Kube => self.render_view_ids(f, input_mask, self.get_remote_kube_view()),
             InputMask::Localhost => unreachable!(),
-            InputMask::Smb => self.render_view_ids(f, input_mask, self.get_remote_smb_view()),
+            InputMask::Smb => self.get_remote_smb_view(),
-            InputMask::WebDAV => self.render_view_ids(f, input_mask, self.get_remote_webdav_view()),
+            InputMask::WebDAV => self.get_remote_webdav_view(),
+        };
+        self.render_form_rows(f, protocol_and_mask_chunks[1], FormTab::Remote, view_ids);
+    }
+
+    /// Splits `area` into four 3-line form rows. When `warning_row` is
+    /// `Some(index)`, a 1-line row is inserted directly above row `index` and
+    /// returned as the second tuple element.
+    fn split_input_mask(area: Rect, warning_row: Option<usize>) -> ([Rect; 4], Option<Rect>) {
+        let mut constraints = Vec::with_capacity(6);
+        for row in 0..4 {
+            if warning_row == Some(row) {
+                constraints.push(Constraint::Length(1));
+            }
+            constraints.push(Constraint::Length(3));
+        }
+        constraints.push(Constraint::Min(0));
+        let chunks = Layout::default()
+            .constraints(constraints)
+            .direction(Direction::Vertical)
+            .split(area);
+
+        let mut rows = [Rect::default(); 4];
+        let mut warning = None;
+        let mut chunk = 0;
+        for (row, slot) in rows.iter_mut().enumerate() {
+            if warning_row == Some(row) {
+                warning = Some(chunks[chunk]);
+                chunk += 1;
+            }
+            *slot = chunks[chunk];
+            chunk += 1;
+        }
+        (rows, warning)
+    }
+
+    /// Returns the visible row index of the SMB dialect radio when the form
+    /// shows SMB and SMB1 is selected; `None` otherwise.
+    #[cfg(posix)]
+    fn smb_dialect_warning_row(&self, form_tab: FormTab, view_ids: &[Id; 4]) -> Option<usize> {
+        let input_mask = match form_tab {
+            FormTab::HostBridge => self.host_bridge_input_mask(),
+            FormTab::Remote => self.remote_input_mask(),
+        };
+        if input_mask != InputMask::Smb || self.get_input_smb_dialect(form_tab) != SmbDialect::Smb1
+        {
+            return None;
+        }
+        let dialect_id = Self::form_tab_id(form_tab, AuthFormId::SmbDialect);
+        view_ids.iter().position(|id| *id == dialect_id)
+    }
+
+    #[cfg(win)]
+    fn smb_dialect_warning_row(&self, _form_tab: FormTab, _view_ids: &[Id; 4]) -> Option<usize> {
+        None
+    }
+
+    fn render_form_rows(
+        &mut self,
+        f: &mut tuirealm::ratatui::Frame<'_>,
+        area: Rect,
+        form_tab: FormTab,
+        view_ids: [Id; 4],
+    ) {
+        let warning_row = self.smb_dialect_warning_row(form_tab, &view_ids);
+        let (rows, warning) = Self::split_input_mask(area, warning_row);
+        #[cfg(posix)]
+        if let Some(rect) = warning {
+            let id = Self::form_tab_id(form_tab, AuthFormId::SmbDialectWarning);
+            self.app.view(&id, f, rect);
+        }
+        #[cfg(win)]
+        let _ = warning;
+        for (id, rect) in view_ids.iter().zip(rows) {
+            self.app.view(id, f, rect);
+        }
     }
 }
 
-    fn render_view_ids(
+#[cfg(test)]
-        &mut self,
+mod test {
-        f: &mut tuirealm::ratatui::Frame<'_>,
+    use pretty_assertions::assert_eq;
-        input_mask: std::rc::Rc<[tuirealm::ratatui::layout::Rect]>,
+    use tuirealm::ratatui::layout::Rect;
-        view_ids: [Id; 4],
+
-    ) {
+    use super::AuthActivity;
-        self.app.view(&view_ids[0], f, input_mask[0]);
+
-        self.app.view(&view_ids[1], f, input_mask[1]);
+    #[test]
-        self.app.view(&view_ids[2], f, input_mask[2]);
+    fn should_split_input_mask_without_warning() {
-        self.app.view(&view_ids[3], f, input_mask[3]);
+        let area = Rect::new(0, 0, 40, 13);
+
+        let (rows, warning) = AuthActivity::split_input_mask(area, None);
+
+        assert_eq!(warning, None);
+        assert_eq!(rows[0], Rect::new(0, 0, 40, 3));
+        assert_eq!(rows[1], Rect::new(0, 3, 40, 3));
+        assert_eq!(rows[2], Rect::new(0, 6, 40, 3));
+        assert_eq!(rows[3], Rect::new(0, 9, 40, 3));
+    }
+
+    #[test]
+    fn should_split_input_mask_with_middle_warning() {
+        let area = Rect::new(0, 0, 40, 13);
+
+        let (rows, warning) = AuthActivity::split_input_mask(area, Some(2));
+
+        assert_eq!(warning, Some(Rect::new(0, 6, 40, 1)));
+        assert_eq!(rows[0], Rect::new(0, 0, 40, 3));
+        assert_eq!(rows[1], Rect::new(0, 3, 40, 3));
+        assert_eq!(rows[2], Rect::new(0, 7, 40, 3));
+        assert_eq!(rows[3], Rect::new(0, 10, 40, 3));
+    }
+
+    #[test]
+    fn should_split_input_mask_with_first_row_warning() {
+        let area = Rect::new(0, 0, 40, 13);
+
+        let (rows, warning) = AuthActivity::split_input_mask(area, Some(0));
+
+        assert_eq!(warning, Some(Rect::new(0, 0, 40, 1)));
+        assert_eq!(rows[0], Rect::new(0, 1, 40, 3));
+        assert_eq!(rows[1], Rect::new(0, 4, 40, 3));
+        assert_eq!(rows[2], Rect::new(0, 7, 40, 3));
+        assert_eq!(rows[3], Rect::new(0, 10, 40, 3));
     }
 }

src/ui/activities/auth/view/mounting.rs

@@ -1,4 +1,6 @@
 use super::*;
+#[cfg(posix)]
+use crate::filetransfer::params::SmbDialect;
 use crate::ui::activities::auth::STORE_KEY_RELEASE_NOTES;
 
 impl AuthActivity {
@@ -705,6 +707,36 @@ impl AuthActivity {
         }
     }
 
+    #[cfg(posix)]
+    pub(in crate::ui::activities::auth) fn mount_smb_dialect(
+        &mut self,
+        form_tab: FormTab,
+        dialect: SmbDialect,
+    ) {
+        let color = self.theme().auth_protocol;
+        let id = Self::form_tab_id(form_tab, AuthFormId::SmbDialect);
+        if let Err(err) = self.app.remount(
+            id,
+            Box::new(components::RadioSmbDialect::new(dialect, form_tab, color)),
+            vec![],
+        ) {
+            error!("Failed to remount component: {err}");
+        }
+    }
+
+    #[cfg(posix)]
+    pub(in crate::ui::activities::auth) fn mount_smb_dialect_warning(&mut self, form_tab: FormTab) {
+        let color = self.theme().misc_warn_dialog;
+        let id = Self::form_tab_id(form_tab, AuthFormId::SmbDialectWarning);
+        if let Err(err) = self.app.remount(
+            id,
+            Box::new(components::SmbDialectWarning::new(color)),
+            vec![],
+        ) {
+            error!("Failed to remount component: {err}");
+        }
+    }
+
     pub(in crate::ui::activities::auth) fn mount_webdav_uri(
         &mut self,
         form_tab: FormTab,

src/ui/activities/auth/view/query.rs

@@ -5,10 +5,14 @@ use tuirealm::state::{State, StateValue};
 
 use super::*;
 use crate::filetransfer::FileTransferParams;
+#[cfg(posix)]
+use crate::filetransfer::params::SmbDialect;
 use crate::filetransfer::params::{
     AwsS3Params, GenericProtocolParams, GoogleCloudStorageParams, KubeProtocolParams,
     ProtocolParams, SmbParams, WebDAVProtocolParams,
 };
+#[cfg(posix)]
+use crate::ui::activities::auth::components::RadioSmbDialect;
 
 impl AuthActivity {
     pub(in crate::ui::activities::auth) fn get_generic_params_input(
@@ -82,6 +86,7 @@ impl AuthActivity {
     ) -> SmbParams {
         let share = self.get_input_smb_share(form_tab);
         let workgroup = self.get_input_smb_workgroup(form_tab);
+        let dialect = self.get_input_smb_dialect(form_tab);
         let address = self.get_input_addr(form_tab);
         let port = self.get_input_port(form_tab);
         let username = self.get_input_username(form_tab);
@@ -92,6 +97,7 @@ impl AuthActivity {
             .username(username)
             .password(password)
             .workgroup(workgroup)
+            .dialect(dialect)
     }
 
     #[cfg(win)]
@@ -452,6 +458,20 @@ impl AuthActivity {
         }
     }
 
+    #[cfg(posix)]
+    pub(in crate::ui::activities::auth) fn get_input_smb_dialect(
+        &self,
+        form_tab: FormTab,
+    ) -> SmbDialect {
+        match self
+            .app
+            .state(&Self::form_tab_id(form_tab, AuthFormId::SmbDialect))
+        {
+            Ok(State::Single(StateValue::Usize(opt))) => RadioSmbDialect::opt_to_dialect(opt),
+            _ => SmbDialect::default(),
+        }
+    }
+
     pub(in crate::ui::activities::auth) fn get_new_bookmark(&self) -> (String, bool) {
         let name = match self.app.state(&Id::BookmarkName) {
             Ok(State::Single(StateValue::String(name))) => name,
@@ -473,8 +493,10 @@ impl AuthActivity {
             + 3
     }
 
-    fn input_mask_size(input_mask: InputMask) -> u16 {
+    pub(in crate::ui::activities::auth) fn input_mask_size(input_mask: InputMask) -> u16 {
         match input_mask {
+            // One extra line for the SMB1 warning above the dialect radio.
+            InputMask::Smb if cfg!(posix) => 13,
             InputMask::AwsS3
             | InputMask::Gcs
             | InputMask::Generic

src/ui/activities/auth/view/visible.rs

@@ -289,15 +289,21 @@ impl AuthActivity {
                 Id::HostBridge(AuthFormId::Password),
                 Id::HostBridge(AuthFormId::SmbWorkgroup),
             ],
-            Some(&Id::HostBridge(AuthFormId::RemoteDirectory)) => [
+            Some(&Id::HostBridge(AuthFormId::SmbDialect)) => [
                 Id::HostBridge(AuthFormId::Username),
                 Id::HostBridge(AuthFormId::Password),
                 Id::HostBridge(AuthFormId::SmbWorkgroup),
+                Id::HostBridge(AuthFormId::SmbDialect),
+            ],
+            Some(&Id::HostBridge(AuthFormId::RemoteDirectory)) => [
+                Id::HostBridge(AuthFormId::Password),
+                Id::HostBridge(AuthFormId::SmbWorkgroup),
+                Id::HostBridge(AuthFormId::SmbDialect),
                 Id::HostBridge(AuthFormId::RemoteDirectory),
             ],
             Some(&Id::HostBridge(AuthFormId::LocalDirectory)) => [
-                Id::HostBridge(AuthFormId::Password),
                 Id::HostBridge(AuthFormId::SmbWorkgroup),
+                Id::HostBridge(AuthFormId::SmbDialect),
                 Id::HostBridge(AuthFormId::RemoteDirectory),
                 Id::HostBridge(AuthFormId::LocalDirectory),
             ],
@@ -336,15 +342,21 @@ impl AuthActivity {
                 Id::Remote(AuthFormId::Password),
                 Id::Remote(AuthFormId::SmbWorkgroup),
             ],
-            Some(&Id::Remote(AuthFormId::RemoteDirectory)) => [
+            Some(&Id::Remote(AuthFormId::SmbDialect)) => [
                 Id::Remote(AuthFormId::Username),
                 Id::Remote(AuthFormId::Password),
                 Id::Remote(AuthFormId::SmbWorkgroup),
+                Id::Remote(AuthFormId::SmbDialect),
+            ],
+            Some(&Id::Remote(AuthFormId::RemoteDirectory)) => [
+                Id::Remote(AuthFormId::Password),
+                Id::Remote(AuthFormId::SmbWorkgroup),
+                Id::Remote(AuthFormId::SmbDialect),
                 Id::Remote(AuthFormId::RemoteDirectory),
             ],
             Some(&Id::Remote(AuthFormId::LocalDirectory)) => [
-                Id::Remote(AuthFormId::Password),
                 Id::Remote(AuthFormId::SmbWorkgroup),
+                Id::Remote(AuthFormId::SmbDialect),
                 Id::Remote(AuthFormId::RemoteDirectory),
                 Id::Remote(AuthFormId::LocalDirectory),
             ],