FTP Server for esp-idf using FATFS/LittleFS.
I found this information.
So, I ported from here.
Directory operations are possible because FATFS/LittlsFS is used.

• FATFS
  Case insensitive.

   ftp> dir
   227 (192,168,10,130,7,232)
   150
   -rw-rw-rw- 1 root root 41 May 08 00:47 long_file_name_support.txt
   drw-rw-rw- 1 root root 0 May 08 00:48 sub_directory1
   drw-rw-rw- 1 root root 0 May 08 00:48 sub_directory2
  

• LittleFS
  Case sensitive.

   ftp> dir
   227 (192,168,10,130,7,232)
   150
   -rw-rw-rw- 1 root root 41 May 08 00:51 LONG_FILE_NAME_SUPPORT.txt
   drw-rw-rw- 1 root root 0 Dec 31 1969 SUB_DIRECTORY1
   drw-rw-rw- 1 root root 0 Dec 31 1969 SUB_DIRECTORY2
   -rw-rw-rw- 1 root root 41 May 08 00:51 long_file_name_support.txt
   drw-rw-rw- 1 root root 0 Dec 31 1969 sub_directory1
   drw-rw-rw- 1 root root 0 Dec 31 1969 sub_directory2
  

ESP-IDF V5.0 or later.
ESP-IDF V4.4 release branch reached EOL in July 2024.
ESP-IDF V5.1 is required when using ESP32-C6.

git clone https://github.com/nopnop2002/esp-idf-ftpServer
cd esp-idf-ftpServer/
idf.py set-target {esp32/esp32s2/esp32s3/esp32c2/esp32c3/esp32c6}
idf.py menuconfig
idf.py flash monitor

If you select FATFS on the built-in SPI flash memory, this project will use partitions_example_fatfs.csv.
If you select LittleFS on the built-in SPI flash memory, this project will use partitions_example_littlefs.csv.
If your board has 4M SPI Flash Memory, you can get more space by changing this.
The maximum partition size that can be specified for the 4M flash model is 0x2F0000(=2,960K).
If you use 4M SPI Flash Memory, you need to change this.
config_flash_size

config-main config-app

This project supports the following file systems.
You can select any one using menuconfig.

• LittleFS on Builtin SPI Flash Memory
• FATFS on Builtin SPI Flash Memory
• FATFS on SD card with SDSPI Interface
• FATFS on SD card with SDMMC Interface (Valid only for ESP32/ESP32S3)

Besides this, ESP32 supports SPIFFS, but this project will not use SPIFFS because it cannot handle directories. Image Image

When using SD card with SDMMC, you can select 1 Line mode or 4 Line mode.
config-filesystem-3 config-filesystem-4

Note:
The connection when using SDSPI, SDMMC will be described later.

Note:
LittleFS requires ESP-IDF V5.2 or later.

config-wifi-sta

You can connect using the mDNS hostname instead of the IP address.
config-wifi-2

You can use static IP.
config-wifi-3

config-wifi-ap

config-server

config-filesystem-SDSPI

You can change it to any pin using menuconfig.

Note:
This project doesn't utilize card detect (CD) and write protect (WP) signals from SD card slot.

Click here for details.

On ESP32, SDMMC peripheral is connected to specific GPIO pins using the IO MUX.
GPIO pins cannot be customized.
GPIO2 and GPIO12 cannot be changed.
Since these GPIOs are BootStrap, it is very tricky to use 4-line SD mode with ESP32.
Click here for details.

config-filesystem-SDMMC-ESP32

On ESP32-S3, SDMMC peripheral is connected to GPIO pins using GPIO matrix.
This allows arbitrary GPIOs to be used to connect an SD card.
Click here for details.
The default settings are as follows. But you can change it.

config-filesystem-SDMMC-ESP32S3

By default, FATFS file names can be up to 8 characters long.
If you use filenames longer than 8 characters, you need to change the values below.
config_long_file_name_support-1 config_long_file_name_support-2 config_long_file_name_support-3

Long File Name on FLASH.
config_long_file_name_support-4

Long File Name on SDCARD.
config_long_file_name_support-5

Short File Name on SDCARD config_long_file_name_support-6

By default, 4096-byte sectors are used.
You can change it to 512-byte sectors using menuconfig.
The 512-byte sector has Performance mode and Safety mode.

config-serctor-seize-1 config-serctor-seize-2 config-serctor-seize-3 config-serctor-seize-4

Using ESP32-CAM board and SanDisk Ultra 16GB Micro SD CARD.
Enable Long filename support (Long filename buffer in heap).

• The server does not support multiple connections.
• The server does not support active connection.
  Only passive connections are supported.
  Unfortunately, Windows standard ftp.exe does not allow passive mode (PASV) connections.
  If you have to make a passive mode connection On Windows, you need to use another software such as FFFTP / WinSCP / FileZilla to connect in passive mode.
• The server can only process these commands.
  • SYST
  • CDUP
  • CWD
  • PWD
  • XPWD(Same as PWD)
  • SIZE
  • MDTM(Always GMT)
  • TYPE
  • USER
  • PASS
  • PASV
  • LIST
  • RETR
  • STOR
  • DELE
  • RMD
  • MKD
  • RNFR(Rename From)
  • RNTO(Rename To)
  • NOOP
  • QUIT
  • APPE
  • NLST

The LilyGo ESP32-S2 development board has a micro SD card slot on the board.
It is connected to the ESP32 by SPI, and the peripheral power is supplied from GPIO14.
With this, you can easily build an FTP server.
No equipment other than the development board is required.
It works very stably.

LilyGo-esp32-s2-1 LilyGo-esp32-s2-2

I tested these client.
You need to set the connection type to Passive Mode.

• WinSCP
  WinScp

• FileZilla
  You need to make this setting when using FileZilla. FileZilla-2 FileZilla-1

• FFFTP
  ffftp

• Windows standard ftp.exe
  Unfortunately, Windows standard ftp.exe does not allow passive mode (PASV) connections.

I sometimes get this error when using external SPI SD card readers.
Requires a PullUp resistor.
sd-card-1

You can see all the logging on the server side by commenting it out here.

void ftp_task (void *pvParameters)
{
 ESP_LOGI(FTP_TAG, "ftp_task start");
 //esp_log_level_set(FTP_TAG, ESP_LOG_WARN); ------------> Comment out
 strcpy(ftp_user, CONFIG_FTP_USER);
 strcpy(ftp_pass, CONFIG_FTP_PASSWORD);
 ESP_LOGI(FTP_TAG, "ftp_user:[%s] ftp_pass:[%s]", ftp_user, ftp_pass);

https://github.com/nopnop2002/esp-idf-ftpClient