Are there a standard method(s) for me to give someone else read-only access to my data?
There are several situations where I may want to give a few people read-only access to some data, but I would rather not give those people my secret passwords that allow full authorization to act as me.
- I want to see pretty stock market graphs, so I want to give this web service enough access to see which stocks/mutual funds/etc. I own, and how much of each one -- but not enough access to buy, sell, etc.
- I want to allow the person who does my taxes enough access to my bank account(s) to download all of last tax year's transactions -- but not enough access to transfer money. (One person at " Could mint.com be more secure, and if so, how? " claims there is an OAuth-like system "designed by the banking system" for this -- what is the name of that system?)
- How to use 'key material' so that multiple people can access protected files?
- I want to allow people I have authorized to do a background check on me to see who my "friends" are on social network sites -- but not enough access to let them add new friends, defriend old friends, change privacy settings on my photos, etc. ( "The Dangers of Asking for Social Network Passwords" ; Job seekers getting asked for Facebook passwords, SNOPA legislation would bar employers from social network passwords, 6 Good Reasons NOT To Ask For Facebook Passwords , etc. )
- When I start using a new social networking site, it would be nice to know which of my friends (that I know from real life or from other online sites or both) already have an account on that site -- but simply handing over my gmail password seems like the wrong thing to do. What is the system called that allegedly lets Etsy ( How can I find my friends on Etsy? ) look at my email contact list without giving Etsy my gmail password? Is there a way to somehow give only a hashed version of the email addresses, so my friends don't "accidentally" get spammed?
- New laws may require me to track who I disclose information to ( HIPAA "Is a W-2 form protected health information?"). I can't do that if Alice simply gives Dr. Bob her password to get her information -- from my point of view down in the server basement, I can't tell the difference between Alice typing her own password and Dr. Bob typing Alice's password. What kind of systems(s) allow Alice to tell my server that she's authorized Dr. Bob to see her information, and then allow me to comply with the law and later tell Alice if/when Dr. Bob actually did access her information?
Are there a standard method(s) for me to give someone else read-only access to my data? I'm kind of hoping this is one of the Solved Problems of Cryptography.
Are there standard method(s) for me to set up a system so that Alice can allow (and later revoke) permission for Dr. Bob to look at her information on my system, but prevent Dr. Bob from accidentally or deliberately modifying her data?
(Decades ago, an excellent answer to this question involved "traditional Unix permissions" and "Unix groups". Perhaps also "setuid" or "setgid").