Hash Permission Examples

Version: 1.0.0 Category: Authentication Purpose: Hash permission bit manipulation, checking, combination, and validation

Overview

The Hash permission (bit value 64) controls transaction signing with Hash permission level. This document covers bit manipulation patterns, permission checking workflows, combination operations, and validation logic with code examples in JavaScript, Python, and Go.

Permission Bit Values

Bit Manipulation

Check Hash Permission

Determine whether a permission value includes the Hash permission bit.

JavaScript:

const hasHashPermission = (permissionValue) => (parseInt(permissionValue) & 64) !== 0;

Python:

def has_hash_permission(permission_value):
    return (int(permission_value) & 64) != 0

Go:

func hasHashPermission(permissionValue int) bool {
    return (permissionValue & 64) != 0
}

Examples:

Add Hash Permission

Add the Hash permission bit to an existing permission value using bitwise OR.

JavaScript:

const addHashPermission = (permissionValue) => parseInt(permissionValue) | 64;

Python:

def add_hash_permission(permission_value):
    return int(permission_value) | 64

Go:

func addHashPermission(permissionValue int) int {
    return permissionValue | 64
}

Examples:

Remove Hash Permission

Remove the Hash permission bit from an existing permission value using bitwise AND with complement.

JavaScript:

const removeHashPermission = (permissionValue) => parseInt(permissionValue) & ~64;

Python:

def remove_hash_permission(permission_value):
    return int(permission_value) & ~64

Go:

func removeHashPermission(permissionValue int) int {
    return permissionValue & ^64
}

Examples:

Toggle Hash Permission

Toggle the Hash permission bit (add if missing, remove if present) using bitwise XOR.

JavaScript:

const toggleHashPermission = (permissionValue) => parseInt(permissionValue) ^ 64;

Python:

def toggle_hash_permission(permission_value):
    return int(permission_value) ^ 64

Go:

func toggleHashPermission(permissionValue int) int {
    return permissionValue ^ 64
}

Examples:

Permission Checking Workflows

Check Permission on a Specific Object

Step 1: Query permissions for the object.

GET /structs/permission/object/{objectId}

Example response for objectId = 0-1:

[
  {
    "permissionId": "0-1@1-11",
    "value": "127",
    "objectId": "0-1",
    "playerId": "1-11"
  }
]

Step 2: Filter for the target player.

filter: permission.playerId === "1-11"

Step 3: Check the Hash permission bit.

(parseInt("127") & 64) !== 0  // true

Check All Permissions for a Player

Step 1: Query all permissions for the player.

GET /structs/permission/player/{playerId}

Example response for playerId = 1-11:

[
  { "permissionId": "0-1@1-11", "value": "127", "objectId": "0-1", "playerId": "1-11" },
  { "permissionId": "2-1@1-11", "value": "64", "objectId": "2-1", "playerId": "1-11" }
]

Step 2: Filter permissions that include the Hash bit.

permissions.filter(p => (parseInt(p.value) & 64) !== 0)

Both permissions above include the Hash bit (127 and 64 both have bit 64 set).

Permission Combination

Combine Multiple Permission Bits

Use bitwise OR to combine multiple permission bits into a single value.

JavaScript:

const combinePermissions = (...bits) => bits.reduce((acc, bit) => acc | bit, 0);

Python:

def combine_permissions(*bits):
    return reduce(lambda acc, bit: acc | bit, bits, 0)

Go:

func combinePermissions(bits ...int) int {
    result := 0
    for _, bit := range bits {
        result |= bit
    }
    return result
}

Examples:

Check Multiple Permission Bits

Verify that a permission value includes all required bits.

JavaScript:

const hasAllPermissions = (permissionValue, ...requiredBits) => {
  const value = parseInt(permissionValue);
  return requiredBits.every(bit => (value & bit) !== 0);
};

Python:

def has_all_permissions(permission_value, *required_bits):
    value = int(permission_value)
    return all((value & bit) != 0 for bit in required_bits)

Go:

func hasAllPermissions(permissionValue int, requiredBits ...int) bool {
    for _, bit := range requiredBits {
        if (permissionValue & bit) == 0 {
            return false
        }
    }
    return true
}

Examples:

Permission Validation

Validate Permission Value Range

Permission values must be integers between 0 and 127 inclusive.

JavaScript:

const isValidPermissionValue = (value) => {
  const num = parseInt(value);
  return num >= 0 && num <= 127 && Number.isInteger(num);
};

Python:

def is_valid_permission_value(value):
    try:
        num = int(value)
        return 0 <= num <= 127
    except ValueError:
        return False

Go:

func isValidPermissionValue(value string) bool {
    num, err := strconv.Atoi(value)
    if err != nil {
        return false
    }
    return num >= 0 && num <= 127
}

Examples:

Validate Hash Permission in Database

Query the database to verify Hash permission format:

SELECT permission_hash FROM permission WHERE object_id = ? AND player_id = ?

Expected values:

• Has Hash permission: permission_hash = true or permission_hash = 1
• No Hash permission: permission_hash = false or permission_hash = 0

Database to API mapping:

Example Workflows

Grant Hash Permission

1. Check current permission: GET /structs/permission/object/{objectId}, filter by playerId
2. Calculate new value: newValue = currentValue | 64 (e.g., 63 becomes 127)
3. Update permission via the appropriate transaction

Revoke Hash Permission

1. Check current permission: GET /structs/permission/object/{objectId}, filter by playerId
2. Calculate new value: newValue = currentValue & ~64 (e.g., 127 becomes 63)
3. Update permission via the appropriate transaction

Check Before Transaction

1. Query player permissions: GET /structs/permission/player/{playerId}
2. Check if the player has Hash permission on the relevant object: (parseInt(permission.value) & 64) !== 0
3. Proceed with the transaction only if hasHashPermission === true

Cross-References

• Database query examples: examples/database/query-examples.md
• Authentication protocol: protocols/authentication.md
• Transaction signing: examples/auth/consensus-transaction-signing.md
• Validation schema: schemas/validation.md