espressif/esp_encrypted_img

uploaded 2 months ago

# ESP Encrypted Image Abstraction Layer [](https://components.espressif.com/components/espressif/esp_encrypted_img) This component provides an API interface to decrypt data defined in "ESP Encrypted Image" format. This format is as specified at [Image Format](#image-format) This component can help in integrating pre encrypted firmware in over-the-air updates. Additionally, this component can also be used for other use-cases which requires addition of encryption layer for custom data. ## Image Format  ```c typedef struct { char magic[4]; char enc_gcm[384]; char iv[16]; char bin_size[4]; char auth[16]; char extra_header[88]; } pre_enc_bin_header; ``` The above struct represents encrypted image header. Note: * RSA-3072 key is provided to the tool externally. You can generate RSA key pair using following command: `openssl genrsa -out rsa_key/private.pem 3072` * AES-GCM key and IV are generated by the tool itself. ## Tool Info This component also contains tool ([esp_enc_img_gen.py](https://github.com/espressif/idf-extra-components/blob/master/esp_encrypted_img/tools/esp_enc_img_gen.py)) to generate encrypted images using RSA3072 public key. ### Encrypt the image ``` python esp_enc_img_gen.py encrypt /path/to/input.bin /path/to/RSA-public-key /path/to/enc.bin ``` ### Decrypt the image ``` python esp_enc_img_gen.py decrypt /path/to/enc.bin /path/to/RSA-private-key /path/to/output.bin ``` To know more about the tool, use command: `python esp_enc_img-gen.py --help` ## API Reference To learn more about how to use this component, please check API Documentation from header file [esp_encrypted_img.h](https://github.com/espressif/idf-extra-components/blob/master/esp_encrypted_img/include/esp_encrypted_img.h)

## 2.2.0 ### Enhancements: - Added an API to get the size of pre encrypted binary image header, this could be useful while computing entire decrypted image length: `esp_encrypted_img_get_header_size` ## 2.1.0 ### Enhancements: - Added an API to abort the decryption process: `esp_encrypted_img_decrypt_abort` - Added an API to check if the complete data has been received: `esp_encrypted_img_is_complete_data_received` ## 2.0.4 - `rsa_pub_key` member of `esp_decrypt_cfg_t` structure is now deprecated. Please use `rsa_priv_key` instead. - `rsa_pub_key_len` member of `esp_decrypt_cfg_t` structure is now deprecated. Please use `rsa_priv_key_len` instead.