Behind Closed Doors: Managing Passwords in a Dangerous World

Transcript

1. Noah Kantrowitz Behind Closed Doors Managing Passwords in a Dangerous World
2. Me • Chef-y dude • @kantrn / coderanger • Bloomberg FOSS
3. Secrets
4. Definition • Small • Radioactive • Required
5. Secrets • Passwords • Tokens
 • Keys • Other
6. Passwords • Computer to computer • 1 to ~1024 bytes • "Internal" or human-y
7. Tokens • "External" or API • Like passwords
8. Keys • Whole files • Bigger, chunkier
9. Other • Kerberos tickets • PCI log files • HIPAA records
10. Temperature
11. Hot / Online • Autonomous access • Used a lot • Humans need not apply
12. Cold / Offline • Used rarely • Humans required
13. Spectrum
14. Speed
15. Slow • "Static" • Change is "big" • Less safe
16. Fast • Changes constantly • Automatic rotation • More safe
17. Properties of a Secrets Management System
18. – Jerome Saltzer, Communications of the ACM “Every program and every privileged user of the system should operate using the least amount of privilege necessary to complete the job.”
19. Properties • Least privilege • Audit trail
20. Let's do it!
21. $ echo "P@s5wd" > secret.txt $ git commit -a -m "yolo!" $ git push origin master To git@github.com:me/myapp.git f35a8c0..c2f0adf master -> master
22. Attack Surfaces
23. Surfaces • Brute force • Code leak • Backup leak • Traversal
 • Code exec • Root exec • Laptop theft • Higher power
24. Brute Force • Always be wary • Rate-limit, restrict, rotate • Make it impossible
25. Code Leak • Read-only access • No data • "GitHub oops"
26. Backup Leak • Still read-only • With database, et al
27. Traversal • /show?n=about • /show?n=../../passwd • /search?q=;select…
28. An Aside • Environment variables • Logged, inherited, etc • Unsafe at any speed
29. Code Exec • Beyond app security • Infrastructure hygiene • Service users
30. Root Exec Lasciate ogne speranza,
 voi ch'intrate
31. Laptop Theft • Use disk encryption • Rotate everything
32. Higher Power • Government • Advanced threat • Natural disaster
33. Cryptography
34. Symmetry • Symmetric vs asymmetric • Shared key vs pairs • Public key not secret
35. Secret Symmetric Admin Server
36. Secret Symmetric Admin Server Key
37. Secret Encrypted Blob Symmetric Admin Server Key
38. Secret Encrypted Blob Symmetric Admin Server Key Key
39. Encrypted Blob Secret Encrypted Blob Symmetric Admin Server Key Key
40. Encrypted Blob Secret Encrypted Blob Secret Symmetric Admin Server Key Key
41. Secret Asymmetric Admin Server
42. Secret Asymmetric Admin Server Key Pair
43. Secret Asymmetric Admin Server Public Key Key Pair
44. Secret Encrypted Blob Asymmetric Admin Server Public Key Key Pair
45. Encrypted Blob Secret Encrypted Blob Asymmetric Admin Server Public Key Key Pair
46. Encrypted Blob Secret Secret Encrypted Blob Asymmetric Admin Server Public Key Key Pair
47. Mode • Pre-encryption • Symmetric key distribution • Asymmetric key identity • Trusted third party
48. Symmetric Pre Admin Servers Store
49. Symmetric Pre Admin Servers Store
50. Symmetric Pre Admin Servers Store
51. Symmetric Pre Admin Servers Store
52. Symmetric Pre Admin Servers Store
53. Symmetric Pre Admin Servers Store
54. Asymmetric Pre Admin Servers Store A B C
55. A B Asymmetric Pre Admin Servers Store A B C
56. A B Asymmetric Pre Admin Servers Store A B A B C
57. A B Asymmetric Pre Admin Servers Store A B A B A B C
58. A B A B Asymmetric Pre Admin Servers Store A B A B A B C
59. A B A B B A Asymmetric Pre Admin Servers Store A B A B A B C
60. A B A B B A Asymmetric Pre Admin Servers Store A B A B A B C
61. Trusted Third Party Admin TTP Servers A B C D
62. Trusted Third Party B C Admin TTP Servers A B C D
63. Trusted Third Party B C Admin TTP Servers A B C D
64. Tools
65. Text Files • git add … • scp … • Interns
66. git-crypt • Git file filter • Symmetric or asymmetric • Footgun
67. Cluster Managers • ZooKeeper, Consul, Etcd • ACLs or bust • Here be dragons
68. Chef Encrypted Bags • Symmetric, AES-256-GCM • Server vs git • Turtles all the way down
69. Ansible Vault • AES-256-CTR + SHA-256 • Still turtles
70. Hiera Eyaml • PKCS7 (or GPG) • Trusted Third Party
71. Chef Vault • RSA(encrypted bags) • Asymmetric pre-encrypt • Kind of still turtle-y
72. Hashicorp Vault • TTP service • New bar for fast secrets • Modular design
73. Keywhiz • TTP • TLS keys, files • Battle tested
74. Private S3 • IAM roles • Complex policy • Easy to get started
75. Amazon KMS • Kool-aid-tastic • Key escrow • Hosted encrypt/decrypt
76. Sneaker • KMS + S3 • Still kool
77. Confidant • KMS + DynamoDB • Web-based • Versioned w/ history
78. Trousseau • Asymmetric pre-encrypt • GPG + modular storage • S3, GPG, GitHub
79. Sops • KMS or GPG • Manual storage
80. Red October • Cold secrets • N of M storage
81. Barbican Pining for the fjords
82. Conjur • And other closed source • Trust but verify
83. HSMs • TPMs otherwise $ $ $ • Dedicated hardware • Bugs not unheard of
84. The Hard Problem
85. Identity • Who are you? • Who am I? • Why are we in this
 hand basket?
86. Pure Identity • TLS client certificates • MySQL, Postgres • Internal APIs
87. Integration
88. API Clients • Vault: HVAC, vault-rails • KMS: botocore, aws-sdk
89. HVAC # local_settings.py import hvac c = hvac.Client( url='https://vaultserver:8200') DATABASES = { 'default': { # Other settings ... 'PASSWORD': c.read('secret/dbpass') } }
90. Config Management • Templates/commands • hiera-vault • Ruby/Python APIs
91. Chef # recipes/myapp.rb execute 'sneaker unpack ...' template 'local_settings.py' do # Other properties ... variables pw: citadel['pw'] end
92. KeywhizFS • FUSE filesystem • Direct key usage • In-memory
93. Consul Templates • Standalone daemon • Sync Vault data to files • CM → Templates → files
94. envconsul • Vault data in $ENV • Beware of logging
95. Summon • Secrets in $ENV • Modular providers • S3, Keyring, Conjur
96. In Summary • Check your privilege and audit trail • Pick types and temperatures • Think about attack surfaces • Have a disaster plan
97. Thank You
98. Questions? @kantrn coderanger.net