Add the ignore_mdc_error flag setter and getter

Add generic `get_ctx_flag` getter and `set_ctx_flag` setter

.gitignore

@@ -6,3 +6,4 @@ coverage
 Gemfile.lock
 /tmp/*
 /ports/*
+.byebug_history

ext/gpgme/gpgme_n.c

@@ -514,6 +514,46 @@ rb_s_gpgme_release (VALUE dummy, VALUE vctx)
  return Qnil;
 }
 
+static VALUE
+rb_s_gpgme_set_ctx_flag (VALUE dummy, VALUE vctx, VALUE vname, VALUE vstr)
+{
+ gpgme_ctx_t ctx;
+ gpgme_error_t err;
+ char* name;
+ char* str;
+
+ name = StringValueCStr(vname);
+ str = StringValueCStr(vstr);
+
+ UNWRAP_GPGME_CTX(vctx, ctx);
+ if (!ctx)
+ rb_raise (rb_eArgError, "released ctx");
+
+ err = gpgme_set_ctx_flag(ctx, name, str);
+ return LONG2NUM(err);
+}
+
+static VALUE
+rb_s_gpgme_get_ctx_flag (VALUE dummy, VALUE vctx, VALUE vname)
+{
+ gpgme_ctx_t ctx;
+ const char* name;
+ int yes;
+
+ name = StringValueCStr(vname);
+
+ UNWRAP_GPGME_CTX(vctx, ctx);
+ if (!ctx)
+ rb_raise (rb_eArgError, "released ctx");
+
+ const char* result;
+ result = gpgme_get_ctx_flag(ctx, name);
+ if (result == NULL)
+ rb_raise (rb_eArgError, "incorrect ctx flag name");
+
+ return rb_str_new_cstr(result);
+}
+
 static VALUE
 rb_s_gpgme_set_protocol (VALUE dummy, VALUE vctx, VALUE vproto)
 {
@@ -566,6 +606,42 @@ rb_s_gpgme_get_armor (VALUE dummy, VALUE vctx)
  return INT2FIX(yes);
 }
 
+static VALUE
+rb_s_gpgme_set_ignore_mdc_error (VALUE dummy, VALUE vctx, VALUE vyes)
+{
+ gpgme_ctx_t ctx;
+ gpgme_error_t err;
+ int yes;
+
+ yes = NUM2INT(vyes);
+
+ UNWRAP_GPGME_CTX(vctx, ctx);
+ if (!ctx)
+ rb_raise (rb_eArgError, "released ctx");
+
+ err = gpgme_set_ctx_flag(ctx, "ignore-mdc-error", yes ? "1" : "");
+ return LONG2NUM(err);
+}
+
+static VALUE
+rb_s_gpgme_get_ignore_mdc_error (VALUE dummy, VALUE vctx)
+{
+ gpgme_ctx_t ctx;
+ int yes;
+
+ UNWRAP_GPGME_CTX(vctx, ctx);
+ if (!ctx)
+ rb_raise (rb_eArgError, "released ctx");
+
+ const char* result;
+ result = gpgme_get_ctx_flag(ctx, "ignore-mdc-error");
+ if (result == NULL)
+ rb_raise (rb_eArgError, "incorrect ctx flag name");
+
+ yes = (result && *result)? !!atoi (result) : 0;
+ return INT2FIX(yes);
+}
+
 static VALUE
 rb_s_gpgme_set_textmode (VALUE dummy, VALUE vctx, VALUE vyes)
 {
@@ -2373,6 +2449,10 @@ Init_gpgme_n (void)
  rb_s_gpgme_release, 1);
 
  /* Context Attributes */
+ rb_define_module_function (mGPGME, "gpgme_set_ctx_flag",
+ rb_s_gpgme_set_ctx_flag, 3);
+ rb_define_module_function (mGPGME, "gpgme_get_ctx_flag",
+ rb_s_gpgme_get_ctx_flag, 2);
  rb_define_module_function (mGPGME, "gpgme_set_protocol",
  rb_s_gpgme_set_protocol, 2);
  rb_define_module_function (mGPGME, "gpgme_get_protocol",
@@ -2381,6 +2461,10 @@ Init_gpgme_n (void)
  rb_s_gpgme_set_armor, 2);
  rb_define_module_function (mGPGME, "gpgme_get_armor",
  rb_s_gpgme_get_armor, 1);
+ rb_define_module_function (mGPGME, "gpgme_set_ignore_mdc_error",
+ rb_s_gpgme_set_ignore_mdc_error, 2);
+ rb_define_module_function (mGPGME, "gpgme_get_ignore_mdc_error",
+ rb_s_gpgme_get_ignore_mdc_error, 1);
  rb_define_module_function (mGPGME, "gpgme_set_textmode",
  rb_s_gpgme_set_textmode, 2);
  rb_define_module_function (mGPGME, "gpgme_get_textmode",

lib/gpgme/ctx.rb

@@ -49,12 +49,13 @@ def self.new(options = {})
  raise exc if exc
  ctx = rctx[0]
 
- ctx.protocol = options[:protocol] if options[:protocol]
- ctx.armor = options[:armor] if options[:armor]
- ctx.textmode = options[:textmode] if options[:textmode]
- ctx.keylist_mode = options[:keylist_mode] if options[:keylist_mode]
- ctx.pinentry_mode = options[:pinentry_mode] if options[:pinentry_mode]
- ctx.offline = options[:offline] if options[:offline]
+ ctx.protocol = options[:protocol] if options[:protocol]
+ ctx.armor = options[:armor] if options[:armor]
+ ctx.textmode = options[:textmode] if options[:textmode]
+ ctx.keylist_mode = options[:keylist_mode] if options[:keylist_mode]
+ ctx.pinentry_mode = options[:pinentry_mode] if options[:pinentry_mode]
+ ctx.offline = options[:offline] if options[:offline]
+ ctx.ignore_mdc_error = options[:ignore_mdc_error] if options[:ignore_mdc_error]
 
  if options[:password]
  ctx.set_passphrase_callback GPGME::Ctx.method(:pass_function),
@@ -103,6 +104,43 @@ def release
  # Getters and setters
  ##
 
+ # Get the value of the Ctx flag with the given name.
+ #
+ # Allowed flag names may include:
+ # - 'redraw'
+ # - 'full-status'
+ # - 'raw-description'
+ # - 'export-session-key'
+ # - 'override-session-key'
+ # - 'include-key-block'
+ # - 'auto-key-import'
+ # - 'auto-key-retrieve'
+ # - 'request-origin'
+ # - 'no-symkey-cache'
+ # - 'ignore-mdc-error'
+ # - 'auto-key-locate'
+ # - 'trust-model'
+ # - 'extended-edit'
+ # - 'cert-expire'
+ # - 'key-origin'
+ # - 'import-filter'
+ # - 'no-auto-check-trustdb'
+ #
+ # Please consult the GPGPME documentation for more details
+ #
+ def get_ctx_flag(flag_name)
+ GPGME::gpgme_get_ctx_flag(self, flag_name.to_s)
+ end
+
+ # Set the Ctx flag with the given name
+ # to the given value.
+ def set_ctx_flag(flag_name, val)
+ err = GPGME::gpgme_set_ctx_flag(self, flag_name.to_s, val.to_s)
+ exc = GPGME::error_to_exception(err)
+ raise exc if exc
+ val
+ end
+
  # Set the +protocol+ used within this context. See {GPGME::Ctx.new} for
  # possible values.
  def protocol=(proto)
@@ -128,6 +166,22 @@ def armor
  GPGME::gpgme_get_armor(self) == 1 ? true : false
  end
 
+ # This option ignores a MDC integrity protection failure.
+ # It is required to decrypt old messages which did not use an MDC.
+ # It may also be useful if a message is partially garbled,
+ # but it is necessary to get as much data as possible out of that garbled message.
+ # Be aware that a missing or failed MDC can be an indication of an attack.
+ # Use with great caution.
+ def ignore_mdc_error=(yes)
+ GPGME::gpgme_set_ignore_mdc_error(self, yes ? 1 : 0)
+ yes
+ end
+
+ # Return true if the MDC integrity protection is disabled.
+ def ignore_mdc_error
+ GPGME::gpgme_get_ignore_mdc_error(self) == 1 ? true : false
+ end
+
  # Tell whether canonical text mode should be used.
  def textmode=(yes)
  GPGME::gpgme_set_textmode(self, yes ? 1 : 0)

test/ctx_test.rb

@@ -81,6 +81,70 @@
  end
  end
 
+ describe :get_ctx_flag do
+ it "reads flags with getters and setters" do
+ ctx = GPGME::Ctx.new
+
+ refute ctx.ignore_mdc_error
+ assert_equal "", ctx.get_ctx_flag("ignore-mdc-error")
+
+ ctx.ignore_mdc_error = true
+
+ assert ctx.ignore_mdc_error
+ assert_equal "1", ctx.get_ctx_flag("ignore-mdc-error")
+ end
+
+ it "can get flags without getters and setters" do
+ ctx = GPGME::Ctx.new
+
+ assert_equal "", ctx.get_ctx_flag("auto-key-locate")
+ ctx.set_ctx_flag("auto-key-locate", "cert")
+ assert_equal "cert", ctx.get_ctx_flag("auto-key-locate")
+ end
+
+ it "raises an error when a flag doesn't exist" do
+ ctx = GPGME::Ctx.new
+
+ assert_raises ArgumentError do
+ ctx.get_ctx_flag("foo")
+ end
+ end
+ end
+
+ describe :set_ctx_flag do
+ it "sets the value for a flag with a getter" do
+ ctx = GPGME::Ctx.new
+ refute ctx.ignore_mdc_error
+
+ ctx.set_ctx_flag("ignore-mdc-error", "1")
+ assert ctx.ignore_mdc_error
+ end
+
+ it "unsets the value for a flag with a getter" do
+ ctx = GPGME::Ctx.new(ignore_mdc_error: true)
+ assert ctx.ignore_mdc_error
+
+ ctx.set_ctx_flag("ignore-mdc-error", "0")
+ refute ctx.ignore_mdc_error
+ end
+
+ it "can set flags without getters and setters" do
+ ctx = GPGME::Ctx.new
+
+ assert_equal "", ctx.get_ctx_flag("auto-key-locate")
+ ctx.set_ctx_flag("auto-key-locate", "cert")
+ assert_equal "cert", ctx.get_ctx_flag("auto-key-locate")
+ end
+
+ it "raises an error when a flag doesn't exist" do
+ ctx = GPGME::Ctx.new
+
+ assert_raises GPGME::Error do
+ ctx.set_ctx_flag("foo", "bar")
+ end
+ end
+ end
+
  describe :armor do
  it "sets false by default" do
  ctx = GPGME::Ctx.new
@@ -101,6 +165,66 @@
  end
  end
 
+ describe :ignore_mdc_error do
+ it "sets false by default" do
+ ctx = GPGME::Ctx.new
+ refute ctx.ignore_mdc_error
+ end
+
+ it "can set" do
+ ctx = GPGME::Ctx.new
+ ctx.ignore_mdc_error = true
+ assert ctx.ignore_mdc_error
+ end
+
+ it "can set and unset" do
+ ctx = GPGME::Ctx.new
+
+ ctx.ignore_mdc_error = true
+ assert ctx.ignore_mdc_error
+
+ ctx.ignore_mdc_error = false
+ refute ctx.ignore_mdc_error
+ end
+
+ it "can set and get in constructor" do
+ ctx = GPGME::Ctx.new(:ignore_mdc_error => false)
+ refute ctx.ignore_mdc_error
+ ctx = GPGME::Ctx.new(:ignore_mdc_error => true)
+ assert ctx.ignore_mdc_error
+ end
+ end
+
+ describe :ignore_mdc_error do
+ it "sets false by default" do
+ ctx = GPGME::Ctx.new
+ refute ctx.ignore_mdc_error
+ end
+
+ it "can set" do
+ ctx = GPGME::Ctx.new
+
+ ctx.ignore_mdc_error = true
+ assert ctx.ignore_mdc_error
+ end
+
+ it "can unset" do
+ ctx = GPGME::Ctx.new(ignore_mdc_error: true)
+ assert ctx.ignore_mdc_error
+
+ ctx.ignore_mdc_error = false
+ refute ctx.ignore_mdc_error
+ end
+
+ it "can set and get in constructor" do
+ ctx = GPGME::Ctx.new(:ignore_mdc_error => false)
+ refute ctx.ignore_mdc_error
+
+ ctx = GPGME::Ctx.new(:ignore_mdc_error => true)
+ assert ctx.ignore_mdc_error
+ end
+ end
+
  describe :protocol do
  it "sets 0 by default" do
  ctx = GPGME::Ctx.new