X7ROOT File Manager
Current Path:
/usr/share/doc/corosync-2.4.5
usr
/
share
/
doc
/
corosync-2.4.5
/
📁
..
📄
LICENSE
(3.07 KB)
📄
SECURITY
(3.66 KB)
Editing: SECURITY
Security Design of corosync The corosync project intends to mitigate the following threats: 1. forged group messaging messages which are intended to fault the corosync executive 2. forged group messaging messages which are intended to fault applications using corosync apis 3. monitoring of network data to capture sensitive information The corosync project does not intend to mitigate the following threats: 1. physical access to the hardware which could expose the private key 2. privledged access to the operating system which could expose the private key or be used to inject errors into the corosync executive. 3. library user creates requests which are intended to fault the corosync executive The corosync project mitigates the threats using two mechanisms: 1. Authentication 2. Secrecy Library Interface ----------------- The corosync executive authenticates every library user. The library is only allowed to access services if it's GID is corosync or 0. Unauthorized library users are rejected. The corosync group is a trusted group. If the administrator doesn't trust the application, it should not be added to the group! Any member of the corosync group could potentially send a malformed request to the executive and cause it to fault. Group Messaging Interface ------------------------- Group messaging uses UDP/IP to communicate with other corosync executives using messages. It is possible without authentication of every packet that an attacker could forge messages. These forged messages could fault the corosync executive distributed state machines. It would also be possible to corrupt end applications by forging changes. Since messages are sent using UDP/IP it would be possible to snoop those messages and rebuild sensitive data. To solve these problems, the group messaging interface uses two new interfaces interal to it's implementation: 1. encrypt_and_sign - encrypts and signs a message securely 2. authenticate_and_decrypt - authenticates and decrypts a message securely When the executive wants to send a message over the network, it uses encrypt_and_sign to prepare the message to be sent. When the executive wants to receive a message from the network, it uses authenticate_and_decrypt to verify the message is valid and decrypt it. Corosync uses AES256/SHA-1 by default from the Mozilla Network Security Services (libnss) library. It supports the following choices for ciphers: 3des, aes128, aes192, aes256, and the following choices for hash algorithms: md5, sha1, sha256, sha384, sha512. The internal functions utilize the following algorithms by default: sha1 - hash algorithm secure for using with hmac hmac - produces a 16 byte digest from any length input Every message starts with a struct security { unsigned char digest[20]; A one way hash digest unsigned char salt[16]; A securely generated random number } USING LIBNSS ------------ When corosync is started up libnss is initialised, the private key is read into memory and stored for later use by the code. When a message is sent (encrypt_and_sign): ------------------------------------------ - The message is encrypted using the chosen cipher (AES256 by default). - A digest of that message is then created using the chosen hash algorithm (SHA1 by default) and based on the private key. - the message is then transmitted. When a message is received (decrypt_and_authenticate): - A Digest of the encrypted message is created using the private key - That digest is compared to the one in the message security_header - If they do not match the packet is rejected - If they do match then the message is decrypted using the private key. - The message is processed. Comments welcome mailto:users@clusterlabs.org
Upload File
Create Folder