Archives for July 2020

AWS IAM MFA

July 28, 2020

Here’s how to give AWS IAM users the ability to manage their own (MFA) Multi Factor Authentication. MFA makes your AWS console secure. AWS IAM users will be able to turn on MFA, using virtual devices such as Google Authenticator to secure their cloud accounts. Here’s the policy.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "AllowViewAccountInfo",
      "Effect": "Allow",
      "Action": "iam:ListVirtualMFADevices",
      "Resource": "*"
    },
    {
      "Sid": "AllowManageOwnVirtualMFADevice",
      "Effect": "Allow",
      "Action": [
        "iam:CreateVirtualMFADevice",
        "iam:DeleteVirtualMFADevice"
      ],
      "Resource": "arn:aws:iam::*:mfa/${aws:username}"
    },
    {
      "Sid": "AllowManageOwnUserMFA",
      "Effect": "Allow",
      "Action": [
        "iam:DeactivateMFADevice",
        "iam:EnableMFADevice",
        "iam:ListUsers",
        "iam:GetUser",
        "iam:ListMFADevices",
        "iam:ResyncMFADevice"
      ],
      "Resource": "arn:aws:iam::*:user/${aws:username}"
    }
  ]
}

AWS IAM Self Manage Policy

July 28, 2020

Here’s the permission needed for an AWS user to manage their own IAM account. The policy allows them to view their own account information, change their own passwords, rotate access keys and certificates, and manage their own git credentials.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "AllowViewAccountInfo",
            "Effect": "Allow",
            "Action": [
                "iam:GetAccountPasswordPolicy",
                "iam:GetAccountSummary"
            ],
            "Resource": "*"
        },
        {
            "Sid": "AllowManageOwnPasswords",
            "Effect": "Allow",
            "Action": [
                "iam:ChangePassword",
                "iam:GetUser"
            ],
            "Resource": "arn:aws:iam::*:user/${aws:username}"
        },
        {
            "Sid": "AllowManageOwnAccessKeys",
            "Effect": "Allow",
            "Action": [
                "iam:CreateAccessKey",
                "iam:DeleteAccessKey",
                "iam:GetAccessKeyLastUsed",
                "iam:ListAccessKeys",
                "iam:UpdateAccessKey"
            ],
            "Resource": "arn:aws:iam::*:user/${aws:username}"
        },
        {
            "Sid": "AllowManageOwnSigningCertificates",
            "Effect": "Allow",
            "Action": [
                "iam:DeleteSigningCertificate",
                "iam:ListSigningCertificates",
                "iam:UpdateSigningCertificate",
                "iam:UploadSigningCertificate"
            ],
            "Resource": "arn:aws:iam::*:user/${aws:username}"
        },
        {
            "Sid": "AllowManageOwnSSHPublicKeys",
            "Effect": "Allow",
            "Action": [
                "iam:DeleteSSHPublicKey",
                "iam:GetSSHPublicKey",
                "iam:ListSSHPublicKeys",
                "iam:UpdateSSHPublicKey",
                "iam:UploadSSHPublicKey"
            ],
            "Resource": "arn:aws:iam::*:user/${aws:username}"
        },
        {
            "Sid": "AllowManageOwnGitCredentials",
            "Effect": "Allow",
            "Action": [
                "iam:CreateServiceSpecificCredential",
                "iam:DeleteServiceSpecificCredential",
                "iam:ListServiceSpecificCredentials",
                "iam:ResetServiceSpecificCredential",
                "iam:UpdateServiceSpecificCredential"
            ],
            "Resource": "arn:aws:iam::*:user/${aws:username}"
        }
    ]
}

{ "Version": "2012-10-17", "Statement": [ { "Sid": "AllowViewAccountInfo", "Effect": "Allow", "Action": [ "iam:GetAccountPasswordPolicy", "iam:GetAccountSummary" ], "Resource": "*" }, { "Sid": "AllowManageOwnPasswords", "Effect": "Allow", "Action": [ "iam:ChangePassword", "iam:GetUser" ], "Resource": "arn:aws:iam::*:user/${aws:username}" }, { "Sid": "AllowManageOwnAccessKeys", "Effect": "Allow", "Action": [ "iam:CreateAccessKey", "iam:DeleteAccessKey", "iam:GetAccessKeyLastUsed", "iam:ListAccessKeys", "iam:UpdateAccessKey" ], "Resource": "arn:aws:iam::*:user/${aws:username}" }, { "Sid": "AllowManageOwnSigningCertificates", "Effect": "Allow", "Action": [ "iam:DeleteSigningCertificate", "iam:ListSigningCertificates", "iam:UpdateSigningCertificate", "iam:UploadSigningCertificate" ], "Resource": "arn:aws:iam::*:user/${aws:username}" }, { "Sid": "AllowManageOwnSSHPublicKeys", "Effect": "Allow", "Action": [ "iam:DeleteSSHPublicKey", "iam:GetSSHPublicKey", "iam:ListSSHPublicKeys", "iam:UpdateSSHPublicKey", "iam:UploadSSHPublicKey" ], "Resource": "arn:aws:iam::*:user/${aws:username}" }, { "Sid": "AllowManageOwnGitCredentials", "Effect": "Allow", "Action": [ "iam:CreateServiceSpecificCredential", "iam:DeleteServiceSpecificCredential", "iam:ListServiceSpecificCredentials", "iam:ResetServiceSpecificCredential", "iam:UpdateServiceSpecificCredential" ], "Resource": "arn:aws:iam::*:user/${aws:username}" } ] }

Change Default Editor

July 28, 2020

Ubuntu and Linux Mint use nano as their default editor. You’ll see it if you try to edit crontab or visudo. Now, there’s nothing wrong with nano, but I prefer using vim instead. Here’s how to change the default editor.

sudo update-alternatives --config editor

You’ll be prompted to change the default editor.

There are 4 choices for the alternative editor (providing /usr/bin/editor).
 
  Selection    Path                Priority   Status
------------------------------------------------------------
  0            /bin/nano            40        auto mode
  1            /bin/ed             -100       manual mode
  2            /bin/nano            40        manual mode
* 3            /usr/bin/vim.basic   30        manual mode
  4            /usr/bin/vim.tiny    15        manual mode
 
Press <enter> to keep the current choice[*], or type selection number:

Type 3 to choose vim basic.