esp-idf-ftpServer

FTP Server for esp-idf using FAT file system.
I found this information.
So, I ported from here.
Since it uses the FAT file system instead of SPIFFS, directory operations are possible.
Also, compared to SPIFFS, writing is about three times faster.

Software requirements

ESP-IDF V4.4/V5.x.
ESP-IDF V5.0 is required when using ESP32-C2.
ESP-IDF V5.1 is required when using ESP32-C6.

Installation

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 need more storage space on FLASH, you need to modify partitions_example.csv.

Partition table

# Name,   Type, SubType, Offset,  Size, Flags
# Note: if you have increased the bootloader size, make sure to update the offsets to avoid overlap
nvs,      data, nvs,     0x9000,  0x6000,
phy_init, data, phy,     0xf000,  0x1000,
factory,  app,  factory, 0x10000, 1M,
storage,  data, fat,            , 0xF0000,  ---> This is for FAT file system

If your ESP32 has 4M Flash, you can get more space by changing this.
The maximum partition size of the FAT file system that can be specified on the 4M Flash model is 0x2F0000 (=2,960K).

Configuration

File System Selection

ESP32 supports the following file systems.
You can select any one using menuconfig.

• FAT file system on FLASH
• FAT file system on SPI peripheral SDCARD
• FAT file system on SDMMC peripheral SDCARD(Valid only for ESP32/ESP32S3)
• FAT file system on SPI Flash Memory like Winbond W25Q64(Not supported in this project)
• FAT file system on USB Memory Stick(Not supported in this project)

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

When using MMC SDCARD, you can select 1 Line mode or 4 Line mode.

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

WiFi Setting for Station-MODE

You can connect using the mDNS hostname instead of the IP address.

You can use static IP.

WiFi Setting for AccessPoint-MODE

Using mDNS hostname

• esp-idf V4.4
  If you set CONFIG_MDNS_STRICT_MODE = y in sdkconfig.defaults, the firmware will be built with MDNS_STRICT_MODE.
  If MDNS_STRICT_MODE is not set, mDNS name resolution will not be possible after long-term operation.
• esp-idf V4.4.1
  mDNS component has been updated.
  If you set CONFIG_MDNS_STRICT_MODE = y in sdkconfig.defaults, the firmware will be built with MDNS_STRICT_MODE.
  Even if MDNS_STRICT_MODE is set, mDNS name resolution will not be possible after long-term operation.
• esp-idf V5.0 or later
  mDNS component has been updated.
  Long-term operation is possible without setting MDNS_STRICT_MODE.
  The following lines in sdkconfig.defaults should be removed before menuconfig.
  CONFIG_MDNS_STRICT_MODE=y

FTP Server Setting

Using FAT file system on SPI peripheral SDCARD

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.

Using FAT file system on SDMMC peripheral SDCARD

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.

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.

Using FAT file system on SDSPI peripheral SDCARD

Click here for details.

Using long file name support

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.

Long File Name on FLASH.

Long File Name on SDCARD.

Short File Name on SDCARD

Changing sector size when using wear levelling library

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.

The writing speed of each mode

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

Limitations

• 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

Using LilyGo ESP32-S2

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.

Windows ftp client

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

• WinSCP
  

• FileZilla
  You need to make this setting when using FileZilla.

• FFFTP
  

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

Troubleshooting

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

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);

Reference

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