{"id":15767243,"url":"https://github.com/0x2b3bfa0/qdtar","last_synced_at":"2025-03-31T11:10:05.748Z","repository":{"id":92704340,"uuid":"100417659","full_name":"0x2b3bfa0/qdtar","owner":"0x2b3bfa0","description":"Documentation for the file format used to upgrade the Qisda-ES600 e-reader.","archived":false,"fork":false,"pushed_at":"2021-09-25T20:58:12.000Z","size":40,"stargazers_count":0,"open_issues_count":0,"forks_count":1,"subscribers_count":2,"default_branch":"master","last_synced_at":"2024-10-04T13:21:52.962Z","etag":null,"topics":["bq-avant","bq-avant3","e-reader","es600","qdtar","qisda","s3c2416","tar"],"latest_commit_sha":null,"homepage":"","language":"Shell","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"gpl-2.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/0x2b3bfa0.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2017-08-15T20:40:46.000Z","updated_at":"2019-08-27T16:44:14.000Z","dependencies_parsed_at":"2023-04-26T20:46:32.657Z","dependency_job_id":null,"html_url":"https://github.com/0x2b3bfa0/qdtar","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/0x2b3bfa0%2Fqdtar","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/0x2b3bfa0%2Fqdtar/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/0x2b3bfa0%2Fqdtar/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/0x2b3bfa0%2Fqdtar/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/0x2b3bfa0","download_url":"https://codeload.github.com/0x2b3bfa0/qdtar/tar.gz/refs/heads/master","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":246458000,"owners_count":20780677,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["bq-avant","bq-avant3","e-reader","es600","qdtar","qisda","s3c2416","tar"],"created_at":"2024-10-04T13:21:19.258Z","updated_at":"2025-03-31T11:10:05.727Z","avatar_url":"https://github.com/0x2b3bfa0.png","language":"Shell","funding_links":[],"categories":[],"sub_categories":[],"readme":"# qdtar\n\nA `qdtar` archive is a slightly modified `tar` archive, used to pack the root filesystem in the Qisda ES600 e-reader upgrades. The file name used for these archives is `rootfs.img`, even if it has nothing to do with a disk image.\n\n***\n\nThis kind of file is formed by a header of 978 bytes, whose contents are completely ignored, prepended to a normal `tar` archive. \n\nThe [executable found on the firmware](busybox) zero-fills the header when creating a new archive. However, the archives found in official firmware upgrade packages used a different approach:\n\n* The first 970 bytes of the header were filled with a copy of the first 970 bytes of the `tar` file.\n* The next 8 bytes were used to store the magic number (`QDTAR1.0`).\n\nI suspect that filling of the header with a copy of the first bytes of the `tar` file was only a mistake made by the developer of the packer application. Probably the original code shifts the data on a buffer by copying it to the new offset without taking care of zeroing the contents of the header. There is, however, anoher credible explanation: copying the first bytes of the `tar` archive will fool a normal decompression utility.\n\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2F0x2b3bfa0%2Fqdtar","html_url":"https://awesome.ecosyste.ms/projects/github.com%2F0x2b3bfa0%2Fqdtar","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2F0x2b3bfa0%2Fqdtar/lists"}