Initial commit

5 files changed, 117 insertions, 0 deletions

diff --git a/lua/encrypt/decrypt.lua b/lua/encrypt/decrypt.lua
new file mode 100644
index 0000000..2ae4e2a
--- /dev/null
+++ b/lua/encrypt/decrypt.lua
@@ -0,0 +1,28 @@
+local helpers = require("encrypt.helpers")
+
+---@return string[]
+---@param lines string | string[]
+---@param password string
+local function decrypt_lines(lines, password)
+  return vim.fn.systemlist(
+    "base64 --decode | openssl enc -d -aes-256-cbc -pbkdf2 -salt -in - -out - -k " .. password,
+    lines
+  )
+end
+
+local function decrypt()
+  local password = helpers.getPassword()
+  local encrypted_lines = vim.api.nvim_buf_get_lines(0, 1, -1, false)
+  local decrypted_lines = decrypt_lines(encrypted_lines, password)
+  if vim.v.shell_error ~= 0 then
+    vim.notify("Error decrypting", vim.log.levels.ERROR)
+    return
+  end
+
+  vim.fn.timer_start(0, function()
+    vim.api.nvim_buf_set_lines(0, 0, -1, false, decrypted_lines)
+    vim.bo.modified = false
+  end)
+end
+
+return decrypt
diff --git a/lua/encrypt/encrypt.lua b/lua/encrypt/encrypt.lua
new file mode 100644
index 0000000..5cdf8a9
--- /dev/null
+++ b/lua/encrypt/encrypt.lua
@@ -0,0 +1,25 @@
+local helpers = require("encrypt.helpers")
+
+---@return string[]
+---@param lines string | string[]
+---@param password string
+local function encrypt_lines(lines, password)
+  return vim.fn.systemlist(
+    "openssl enc -aes-256-cbc -pbkdf2 -salt -in - -out - -k " .. password .. " | base64",
+    lines
+  )
+end
+
+local function encrypt()
+  local password = helpers.getPassword()
+  local buf_lines = vim.api.nvim_buf_get_lines(0, 0, -1, false)
+  local encrypted_lines = encrypt_lines(buf_lines, password)
+
+  table.insert(encrypted_lines, 1, helpers.ENCRYPTED_PREFIX)
+
+  vim.fn.writefile(encrypted_lines, vim.fn.expand("%"))
+  vim.bo.modified = false
+  print("Encrypted " .. vim.fn.expand("%:t"))
+end
+
+return encrypt
diff --git a/lua/encrypt/helpers.lua b/lua/encrypt/helpers.lua
new file mode 100644
index 0000000..37a96b3
--- /dev/null
+++ b/lua/encrypt/helpers.lua
@@ -0,0 +1,13 @@
+---@return string
+local function getPassword()
+  local password = vim.b["password"]
+  if password == nil then
+    password = vim.fn.inputsecret("Enter password: ")
+    vim.b["password"] = password
+  end
+  return password
+end
+
+local ENCRYPTED_PREFIX = "# <<<encrypted>>>"
+
+return { getPassword = getPassword, ENCRYPTED_PREFIX = ENCRYPTED_PREFIX }
diff --git a/lua/encrypt/init.lua b/lua/encrypt/init.lua
new file mode 100644
index 0000000..53fc259
--- /dev/null
+++ b/lua/encrypt/init.lua
@@ -0,0 +1,23 @@
+local setupBuffer = require("encrypt.setup-buffer")
+local encrypt = require("encrypt.encrypt")
+local decrypt = require("encrypt.decrypt")
+local helpers = require("encrypt.helpers")
+
+local function setup()
+  vim.api.nvim_create_user_command("X", function()
+    setupBuffer()
+    encrypt()
+  end, {})
+
+  vim.api.nvim_create_autocmd({ "BufReadPost" }, {
+    callback = function()
+      local first_line = vim.api.nvim_buf_get_lines(0, 0, 1, false)[1]
+      if first_line == helpers.ENCRYPTED_PREFIX then
+        setupBuffer()
+        decrypt()
+      end
+    end,
+  })
+end
+
+return { setup = setup }
diff --git a/lua/encrypt/setup-buffer.lua b/lua/encrypt/setup-buffer.lua
new file mode 100644
index 0000000..a09cdfb
--- /dev/null
+++ b/lua/encrypt/setup-buffer.lua
@@ -0,0 +1,28 @@
+local encrypt = require("encrypt.encrypt")
+
+local function createWriteAutoCmd()
+  if vim.b["encryptionAutoCmd"] ~= nil then
+    return
+  end
+
+  vim.b["encryptionAutoCmd"] = vim.api.nvim_create_autocmd({ "BufWriteCmd" }, {
+    callback = function()
+      if vim.b["encrypted"] ~= true then
+        return
+      end
+
+      encrypt()
+    end,
+  })
+end
+
+local function setupBuffer()
+  -- buftype="acwrite" means save using the BufWriteCmd command
+  vim.bo.buftype = "acwrite"
+  vim.bo.swapfile = false
+  vim.bo.undofile = false
+  vim.b["encrypted"] = true
+  createWriteAutoCmd()
+end
+
+return setupBuffer