Oracle Cloud Security Basics

Overview

OCI IAM policy syntax (Allow group X to manage Y in compartment Z) is the number one enterprise complaint. One wrong policy locks you out of your own resources. One missing verb and your automation silently fails with a 404 NotAuthorizedOrNotFound that looks like a missing resource. This skill is the IAM policy cheat sheet with tested patterns for common access scenarios.

Purpose: Write correct IAM policies, manage API keys securely, and understand the OCI permission model.

Prerequisites

• OCI Python SDK — pip install oci
• OCI config file at ~/.oci/config with valid credentials (user, fingerprint, tenancy, region, key_file)
• Tenancy administrator access (to create policies) or membership in a group with manage policies permission
• Python 3.8+

Instructions

Step 1: Understand the Policy Verb Hierarchy

OCI uses four verbs in ascending order of privilege. Each higher verb includes all lower verbs:

Critical: use does NOT include create or delete. This trips up every new OCI team.

Step 2: IAM Policy Syntax

Every OCI policy statement follows this exact structure:

Allow <subject> to <verb> <resource-type> in <location> [where <conditions>]

Subject types:

• group <group-name> — IAM user group
• dynamic-group <dg-name> — resource principals (instances, functions)
• any-user — every authenticated user (use with extreme caution)

Location types:

• tenancy — entire tenancy (root-level policy only)
• compartment <name> — specific compartment
• compartment id <ocid> — by OCID (for automation)

Step 3: Common Policy Patterns

Copy these tested patterns directly. Replace group names and compartment names with your values:

import oci

config = oci.config.from_file("~/.oci/config")
identity = oci.identity.IdentityClient(config)

# Create a policy with multiple statements
tenancy_id = config["tenancy"]

# --- Pattern 1: Full admin for a compartment ---
admin_policy = identity.create_policy(
    oci.identity.models.CreatePolicyDetails(
        compartment_id=tenancy_id,
        name="compartment-admins",
        description="Full admin access to the dev compartment",
        statements=[
            "Allow group DevAdmins to manage all-resources in compartment dev"
        ]
    )
)

# --- Pattern 2: Read-only access (auditors) ---
readonly_policy = identity.create_policy(
    oci.identity.models.CreatePolicyDetails(
        compartment_id=tenancy_id,
        name="auditor-readonly",
        description="Read-only access for auditors",
        statements=[
            "Allow group Auditors to read all-resources in compartment prod"
        ]
    )
)

# --- Pattern 3: Compute-only operators ---
compute_policy = identity.create_policy(
    oci.identity.models.CreatePolicyDetails(
        compartment_id=tenancy_id,
        name="compute-operators",
        description="Manage compute, read networking",
        statements=[
            "Allow group ComputeOps to manage instance-family in compartment prod",
            "Allow group ComputeOps to use virtual-network-family in compartment prod",
            "Allow group ComputeOps to read volume-family in compartment prod"
        ]
    )
)

# --- Pattern 4: Network admins ---
network_policy = identity.create_policy(
    oci.identity.models.CreatePolicyDetails(
        compartment_id=tenancy_id,
        name="network-admins",
        description="Network management only",
        statements=[
            "Allow group NetAdmins to manage virtual-network-family in compartment prod",
            "Allow group NetAdmins to manage load-balancers in compartment prod",
            "Allow group NetAdmins to read instance-family in compartment prod"
        ]
    )
)

# --- Pattern 5: Restrict deletes (protect production) ---
no_delete_policy = identity.create_policy(
    oci.identity.models.CreatePolicyDetails(
        compartment_id=tenancy_id,
        name="no-delete-prod",
        description="Allow manage but block deletes in production",
        statements=[
            "Allow group DevOps to manage all-resources in compartment prod where request.permission != 'INSTANCE_DELETE'",
            "Allow group DevOps to manage all-resources in compartment prod where request.permission != 'BUCKET_DELETE'"
        ]
    )
)
print("Policies created successfully")

Step 4: Key Resource Family Types

Policies use resource families, not individual resource types:

Step 5: API Key Management

Generate and upload API keys for secure programmatic access:

# Generate a 2048-bit RSA key pair
mkdir -p ~/.oci
openssl genrsa -out ~/.oci/oci_api_key.pem 2048
chmod 600 ~/.oci/oci_api_key.pem

# Extract the public key (upload this to OCI Console)
openssl rsa -pubout -in ~/.oci/oci_api_key.pem -out ~/.oci/oci_api_key_public.pem

# Get the key fingerprint (needed for ~/.oci/config)
openssl rsa -pubout -outform DER -in ~/.oci/oci_api_key.pem | openssl md5 -c

Upload the public key in OCI Console: Identity > Users > Your User > API Keys > Add API Key.

Step 6: Configure ~/.oci/config

[DEFAULT]
user=ocid1.user.oc1..exampleuniqueID
fingerprint=aa:bb:cc:dd:ee:ff:00:11:22:33:44:55:66:77:88:99
tenancy=ocid1.tenancy.oc1..exampleuniqueID
region=us-ashburn-1
key_file=~/.oci/oci_api_key.pem

Verify the config:

import oci

config = oci.config.from_file("~/.oci/config")
oci.config.validate_config(config)

identity = oci.identity.IdentityClient(config)
user = identity.get_user(config["user"]).data
print(f"Authenticated as: {user.name} ({user.email})")

Output

Successful completion produces:

• IAM policies granting appropriate access levels per group/role
• An API key pair with the public key uploaded to OCI Console
• A validated ~/.oci/config file with correct user, fingerprint, tenancy, region, and key_file
• Verified authentication confirmed by a successful Identity API call

Error Handling

Important: OCI returns 404 NotAuthorizedOrNotFound for both "resource doesn't exist" and "you don't have permission." Always check IAM policies first.

Examples

List all policies in a compartment:

import oci

config = oci.config.from_file("~/.oci/config")
identity = oci.identity.IdentityClient(config)

policies = identity.list_policies(compartment_id=config["tenancy"]).data
for p in policies:
    print(f"\n{p.name}:")
    for stmt in p.statements:
        print(f"  {stmt}")

Quick policy validation via CLI:

# List all policies in the tenancy root
oci iam policy list --compartment-id <tenancy-ocid> --all

# Check what a specific group can do
oci iam policy list --compartment-id <tenancy-ocid> --all \
  | python3 -c "import sys,json; [print(s) for p in json.load(sys.stdin)['data'] for s in p['statements'] if 'DevOps' in s]"

Resources

• IAM Policy Reference — complete verb and resource-type list
• IAM Policy Syntax — syntax rules and conditions
• Common Policies — Oracle's recommended patterns
• API Key Management — key generation and upload
• Python SDK Reference — IdentityClient API

Next Steps

After IAM policies are in place, see oraclecloud-enterprise-rbac for compartment hierarchy design and dynamic groups, or oraclecloud-multi-env-setup for profile-based environment separation.