rust: fix clippy warnings

Fix the following lints:
- clippy::box_default
- clippy::byte_char_slices
- clippy::collapsible_match
- clippy::manual_clear
- clippy::question_mark
- clippy::to_string_in_format_args
- clippy::useless_borrows_in_formatting
- unused_imports (rustc)

rust/src/detect/byte_math.rs

@@ -350,10 +350,8 @@ fn parse_bytemath(input: &str) -> IResult<&str, DetectByteMathData, RuleParseErr
     // Using left/right shift further restricts the value of nbytes. Note that
     // validation has already ensured nbytes is in [1..10]
     match byte_math.oper {
-        ByteMathOperator::LeftShift | ByteMathOperator::RightShift => {
-            if byte_math.nbytes > 4 {
-                return Err(make_error(format!("nbytes must be 1 through 4 (inclusive) when used with \"<<\" or \">>\"; {} is not valid", byte_math.nbytes)));
-            }
+        ByteMathOperator::LeftShift | ByteMathOperator::RightShift if byte_math.nbytes > 4 => {
+            return Err(make_error(format!("nbytes must be 1 through 4 (inclusive) when used with \"<<\" or \">>\"; {} is not valid", byte_math.nbytes)));
         }
         _ => {}
     };

rust/src/detect/requires.rs

@@ -408,7 +408,7 @@ pub unsafe extern "C" fn SCDetectRequiresStatusLog(
                 "rule was"
             },
             suricata_version,
-            &min_version
+            min_version
         );
         parts.push(msg);
     }
@@ -445,7 +445,7 @@ pub unsafe extern "C" fn SCDetectRequiresStatusLog(
                 "rule was"
             },
             if status.feature_count > 1 { "s" } else { "" },
-            &features
+            features
         );
         parts.push(msg);
     }

rust/src/dhcp/logger.rs

@@ -46,10 +46,8 @@ impl DHCPLogger {
                 {
                     #[allow(clippy::single_match)]
                     match code {
-                        DHCP_OPT_TYPE => {
-                            if !option.data.is_empty() {
-                                return Some(option.data[0]);
-                            }
+                        DHCP_OPT_TYPE if !option.data.is_empty() => {
+                            return Some(option.data[0]);
                         }
                         _ => {}
                     }
@@ -156,10 +154,8 @@ impl DHCPLogger {
                             self.log_opt_routers(js, option)?;
                         }
                     }
-                    DHCP_OPT_VENDOR_CLASS_ID => {
-                        if self.extended && !option.data.is_empty() {
-                            js.set_string_from_bytes("vendor_class_identifier", &option.data)?;
-                        }
+                    DHCP_OPT_VENDOR_CLASS_ID if self.extended && !option.data.is_empty() => {
+                        js.set_string_from_bytes("vendor_class_identifier", &option.data)?;
                     }
                     _ => {}
                 },

rust/src/dhcp/parser.rs

@@ -234,7 +234,6 @@ pub fn parse_dhcp(input: &[u8]) -> IResult<&[u8], DHCPMessage> {
 
 #[cfg(test)]
 mod tests {
-    use crate::dhcp::dhcp::*;
     use crate::dhcp::parser::*;
 
     #[test]

rust/src/http2/detect.rs

@@ -79,10 +79,8 @@ fn http2_tx_has_errorcode(
                         return 1;
                     }
                 }
-                HTTP2FrameTypeData::RSTSTREAM(rst) => {
-                    if rst.errorcode == code {
-                        return 1;
-                    }
+                HTTP2FrameTypeData::RSTSTREAM(rst) if rst.errorcode == code => {
+                    return 1;
                 }
                 _ => {}
             }
@@ -95,10 +93,8 @@ fn http2_tx_has_errorcode(
                         return 1;
                     }
                 }
-                HTTP2FrameTypeData::RSTSTREAM(rst) => {
-                    if rst.errorcode == code {
-                        return 1;
-                    }
+                HTTP2FrameTypeData::RSTSTREAM(rst) if rst.errorcode == code => {
+                    return 1;
                 }
                 _ => {}
             }
@@ -806,7 +802,7 @@ struct Http2ThreadBuf {
 
 #[no_mangle]
 pub unsafe extern "C" fn SCHttp2ThreadBufDataInit(_cfg: *mut c_void) -> *mut c_void {
-    let boxed = Box::new(Http2ThreadBuf::default());
+    let boxed = Box::<Http2ThreadBuf>::default();
     return Box::into_raw(boxed) as *mut c_void;
 }
 
@@ -951,7 +947,7 @@ struct Http2ThreadMultiBuf {
 
 #[no_mangle]
 pub unsafe extern "C" fn SCHttp2ThreadMultiBufDataInit(_cfg: *mut c_void) -> *mut c_void {
-    let boxed = Box::new(Http2ThreadMultiBuf::default());
+    let boxed = Box::<Http2ThreadMultiBuf>::default();
     return Box::into_raw(boxed) as *mut c_void;
 }
 

rust/src/http2/logger.rs

@@ -127,7 +127,7 @@ fn log_http2_frames(frames: &[HTTP2Frame], js: &mut JsonBuilder) -> Result<bool,
                 js.start_object()?;
                 js.set_string(
                     "settings_id",
-                    &format!("SETTINGS{}", &e.id.to_string().to_uppercase()),
+                    &format!("SETTINGS{}", e.id.to_string().to_uppercase()),
                 )?;
                 js.set_uint("settings_value", e.value as u64)?;
                 js.close()?;

rust/src/ike/detect.rs

@@ -187,12 +187,10 @@ pub extern "C" fn SCIkeStateGetSaAttribute(
                             break;
                         }
                     }
-                    IkeV2Transform::DH(ref e) => {
-                        if sa == "alg_dh" {
-                            ret_val = e.0 as u32;
-                            ret_code = 1;
-                            break;
-                        }
+                    IkeV2Transform::DH(ref e) if sa == "alg_dh" => {
+                        ret_val = e.0 as u32;
+                        ret_code = 1;
+                        break;
                     }
                     _ => (),
                 }

rust/src/jsonbuilder.rs

@@ -172,7 +172,7 @@ impl JsonBuilder {
     // Reset the builder to its initial state, without losing
     // the current capacity.
     pub fn reset(&mut self) {
-        self.buf.truncate(0);
+        self.buf.clear();
         self.state.clear();
         match self.init_type {
             Type::Array => {
@@ -1618,6 +1618,4 @@ static ESCAPED: [u8; 256] = [
     __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // F
 ];
 
-pub static HEX: [u8; 16] = [
-    b'0', b'1', b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', b'a', b'b', b'c', b'd', b'e', b'f',
-];
+pub static HEX: [u8; 16] = *b"0123456789abcdef";

rust/src/mime/mime.rs

@@ -117,14 +117,10 @@ pub fn mime_find_header_token<'a>(
                     // check for initial section of a parameter
                     current_section_slice.extend_from_slice(token);
                     current_section_slice.extend_from_slice(b"*0");
-                    match t.tokens.get(&current_section_slice[..]) {
-                        Some(value) => {
-                            sections_values.extend_from_slice(value);
-                            let l = current_section_slice.len();
-                            current_section_slice[l - 1] = b'1';
-                        }
-                        None => return None,
-                    }
+                    let value = t.tokens.get(&current_section_slice[..])?;
+                    sections_values.extend_from_slice(value);
+                    let l = current_section_slice.len();
+                    current_section_slice[l - 1] = b'1';
                 }
             }
 

rust/src/nfs/nfs4.rs

@@ -380,11 +380,11 @@ impl NFSState {
                             .put(rd.value.to_vec(), xidmap.file_name.to_vec());
                     }
                 }
-                Nfs4ResponseContent::PutRootFH(s) => {
-                    if s == NFS4_OK && xidmap.file_name.is_empty() {
-                        xidmap.file_name = b"<mount_root>".to_vec();
-                        SCLogDebug!("filename {:?}", xidmap.file_name);
-                    }
+                Nfs4ResponseContent::PutRootFH(s)
+                    if s == NFS4_OK && xidmap.file_name.is_empty() =>
+                {
+                    xidmap.file_name = b"<mount_root>".to_vec();
+                    SCLogDebug!("filename {:?}", xidmap.file_name);
                 }
                 _ => {}
             }

rust/src/sdp/parser.rs

@@ -263,9 +263,9 @@ fn parse_connection_data(i: &[u8]) -> IResult<&[u8], String> {
 
     let mut connection_data = format!(
         "{} {} {}",
-        &nettype,
-        &addrtype,
-        &connection_address.to_string()
+        nettype,
+        addrtype,
+        connection_address
     );
     if let Some(ttl) = ttl {
         connection_data = format!("{}/{}", connection_data, ttl);
@@ -463,7 +463,7 @@ fn parse_media_description(i: &[u8]) -> IResult<&[u8], MediaDescription> {
     } else {
         format!("{}", port)
     };
-    let mut media_str = format!("{} {} {}", &media, &port, &proto);
+    let mut media_str = format!("{} {} {}", media, port, proto);
     if !fmt.is_empty() {
         let fmt: Vec<String> = fmt.into_iter().map(String::from).collect();
         media_str = format!("{} {}", media_str, fmt.join(" "));

rust/src/ssh/parser.rs

@@ -164,7 +164,7 @@ pub struct SshPacketKeyExchange<'a> {
     pub reserved: u32,
 }
 
-const SSH_HASSH_STRING_DELIMITER_SLICE: [u8; 1] = [b';'];
+const SSH_HASSH_STRING_DELIMITER_SLICE: [u8; 1] = *b";";
 
 impl SshPacketKeyExchange<'_> {
     pub fn generate_hassh(

rust/suricatasc/src/unix/client.rs

@@ -62,7 +62,7 @@ impl Client {
     {
         let mut encoded = serde_json::to_string(&msg)?;
         if self.verbose {
-            println!("SND: {}", &encoded);
+            println!("SND: {}", encoded);
         }
         encoded.push('\n');
         self.socket.write_all(encoded.as_bytes())?;

rust/suricatasc/src/unix/main.rs

@@ -39,13 +39,13 @@ pub fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let verbose = args.verbose;
     if verbose {
-        println!("Using Suricata command socket: {}", &socket_filename);
+        println!("Using Suricata command socket: {}", socket_filename);
     }
 
     let client = match Client::connect(&socket_filename, verbose) {
         Ok(client) => client,
         Err(err) => {
-            eprintln!("Unable to connect socket to {}: {}", &socket_filename, err);
+            eprintln!("Unable to connect socket to {}: {}", socket_filename, err);
             std::process::exit(1);
         }
     };
@@ -95,7 +95,7 @@ fn run_interactive(mut client: Client) -> Result<(), Box<dyn std::error::Error>>
                             break;
                         }
                         if let Err(err) = client.reconnect() {
-                            println!("Error: {}", &err);
+                            println!("Error: {}", err);
                             break;
                         } else {
                             retry = true;