Remove the ffi crates.

  - Remove the general-purpose ffi crates.  They will be moved into
    their own repository.  Note that we consider general-purpose ffi
    crates to be a dead end: exposing Sequoia's interface requires a
    large number of types and functions, and using the interface from
    C turned out to be verbose and error-prone.  Instead, we prefer to
    write point solutions in Rust that implement exactly the
    functionality the downstream consumer needs, then expose this via
    ffi bindings.

  - See https://gitlab.com/sequoia-pgp/sequoia-ffi.

36 files changed, 0 insertions, 2786 deletions

diff --git a/ffi/.gitignore b/ffi/.gitignore
deleted file mode 100644
index 4e5bd39d..00000000
--- a/ffi/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-sequoia.pc
diff --git a/ffi/Cargo.toml b/ffi/Cargo.toml
deleted file mode 100644
index 8c063981..00000000
--- a/ffi/Cargo.toml
+++ /dev/null
@@ -1,49 +0,0 @@
-[package]
-name = "sequoia-ffi"
-description = "C API for Sequoia"
-version = "0.22.0"
-authors = [
-    "Justus Winter <justus@sequoia-pgp.org>",
-    "Kai Michaelis <kai@sequoia-pgp.org>",
-    "Neal H. Walfield <neal@sequoia-pgp.org>",
-]
-documentation = "https://docs.sequoia-pgp.org/0.22.0/sequoia_ffi"
-homepage = "https://sequoia-pgp.org/"
-repository = "https://gitlab.com/sequoia-pgp/sequoia"
-readme = "../README.md"
-keywords = ["cryptography", "openpgp", "pgp", "encryption", "signing"]
-categories = ["cryptography", "authentication", "development-tools::ffi",
-              "email"]
-license = "LGPL-2.0-or-later"
-edition = "2018"
-
-[badges]
-gitlab = { repository = "sequoia-pgp/sequoia" }
-maintenance = { status = "actively-developed" }
-
-[dependencies]
-sequoia-ffi-macros = { path = "../ffi-macros", version = "0.22" }
-sequoia-openpgp = { path = "../openpgp", version = "1.0.0", default-features = false }
-sequoia-net = { path = "../net", version = "0.24", default-features = false }
-sequoia-ipc = { path = "../ipc", version = "0.27", default-features = false }
-anyhow = "1.0.18"
-lazy_static = "1.4.0"
-libc = "0.2.66"
-memsec = { version = ">=0.5", default-features = false }
-native-tls = "0.2.0"
-tokio = { version = "1.13.1", features = ["rt", "time"] }
-
-[dev-dependencies]
-filetime = "0.2"
-
-[lib]
-crate-type = ["cdylib", "staticlib"]
-bench = false
-
-[features]
-default = ["sequoia-openpgp/default"]
-crypto-nettle = ["sequoia-openpgp/crypto-nettle"]
-crypto-cng = ["sequoia-openpgp/crypto-cng"]
-compression = ["sequoia-openpgp/compression"]
-compression-deflate = ["sequoia-openpgp/compression-deflate"]
-compression-bzip2 = ["sequoia-openpgp/compression-bzip2"]
diff --git a/ffi/LICENSE.txt b/ffi/LICENSE.txt
deleted file mode 120000
index 4ab43736..00000000
--- a/ffi/LICENSE.txt
+++ /dev/null
@@ -1 +0,0 @@
-../LICENSE.txt
\ No newline at end of file
diff --git a/ffi/Makefile b/ffi/Makefile
deleted file mode 100644
index 9a10501b..00000000
--- a/ffi/Makefile
+++ /dev/null
@@ -1,91 +0,0 @@
-# Makefile for Sequoia's bindings.
-
-# Configuration.
-PREFIX		?= /usr/local
-DESTDIR		?=
-
-CARGO	?= cargo
-CARGO_TARGET_DIR	?= $(shell pwd)/../target
-# We currently only support absolute paths.
-CARGO_TARGET_DIR	:= $(abspath $(CARGO_TARGET_DIR))
-
-VERSION		?= $(shell grep '^version[[:space:]]*=[[:space:]]*' Cargo.toml | cut -d'"' -f2)
-VERSION_MAJOR	= $(shell echo $(VERSION) | cut -d'.' -f1)
-
-# Build the right library
-ifeq ($(shell uname -s), Darwin)
-	_SEQ_LIB_EXT	= dylib
-else
-	_SEQ_LIB_EXT	= so
-endif
-
-# Tools.
-ifneq ($(filter Darwin %BSD,$(shell uname -s)),)
-	INSTALL		?= ginstall
-else
-	INSTALL		?= install
-endif
-
-# Make sure subprocesses pick these up.
-export PREFIX
-export DESTDIR
-
-# $(1) = install dir
-# $(2) = whether to set libdir and prefix to $(1) (empty string = false)
-sequoia_pc = \
-	sed -e 's|VERSION|$(VERSION)|g' \
-	    $(if $(2),-e 's|PREFIX|$(shell pwd)|g',-e's|PREFIX|$(PREFIX)|g') \
-	    $(if $(2),-e 's|libdir=.*|libdir=$(1)|g') \
-	  sequoia.pc.in \
-	  >$(1)/sequoia.pc
-
-all: build
-
-.PHONY: build
-build:
-	$(MAKE) -Clang/python build
-	$(call sequoia_pc,$(CARGO_TARGET_DIR)/debug,true)
-
-# Testing and examples.
-.PHONY: test check
-test check:
-	$(MAKE) -Clang/python test
-
-.PHONY: examples
-examples:
-	$(MAKE) -Cexamples --always-make
-
-# Installation.
-.PHONY: build-release
-build-release:
-	CARGO_TARGET_DIR=$(CARGO_TARGET_DIR) \
-	    $(CARGO) build $(CARGO_FLAGS) --release --package sequoia-ffi
-	$(MAKE) -Clang/python build-release
-	$(call sequoia_pc,$(CARGO_TARGET_DIR)/release,true)
-
-.PHONY: install
-install: build-release
-	$(INSTALL) -d $(DESTDIR)$(PREFIX)/share/pkgconfig
-	$(call sequoia_pc,$(DESTDIR)$(PREFIX)/share/pkgconfig,)
-	$(INSTALL) -d $(DESTDIR)$(PREFIX)/include
-	$(INSTALL) -t $(DESTDIR)$(PREFIX)/include include/sequoia.h
-	$(INSTALL) -d $(DESTDIR)$(PREFIX)/include/sequoia
-	$(INSTALL) -t $(DESTDIR)$(PREFIX)/include/sequoia \
-		include/sequoia/*.h
-	$(INSTALL) -d $(DESTDIR)$(PREFIX)/lib
-	$(INSTALL) $(CARGO_TARGET_DIR)/release/libsequoia_ffi.$(_SEQ_LIB_EXT) \
-		$(DESTDIR)$(PREFIX)/lib/libsequoia_ffi.$(_SEQ_LIB_EXT).$(VERSION)
-	ln -fs libsequoia_ffi.$(_SEQ_LIB_EXT).$(VERSION) \
-		$(DESTDIR)$(PREFIX)/lib/libsequoia_ffi.$(_SEQ_LIB_EXT).$(VERSION_MAJOR)
-	ln -fs libsequoia_ffi.$(_SEQ_LIB_EXT).$(VERSION) \
-		$(DESTDIR)$(PREFIX)/lib/libsequoia_ffi.$(_SEQ_LIB_EXT)
-	$(INSTALL) $(CARGO_TARGET_DIR)/release/libsequoia_ffi.a \
-		$(DESTDIR)$(PREFIX)/lib/libsequoia_ffi.a
-	# Now the bindings.
-	$(MAKE) -Clang/python install
-
-# Housekeeping.
-.PHONY: clean
-clean:
-	$(MAKE) -Cexamples clean
-	$(MAKE) -Clang/python clean
diff --git a/ffi/examples/Makefile b/ffi/examples/Makefile
deleted file mode 100644
index 6186d6b9..00000000
--- a/ffi/examples/Makefile
+++ /dev/null
@@ -1,28 +0,0 @@
-# Makefile for examples written in C.
-
-CARGO	?= cargo
-CARGO_TARGET_DIR	?= $(shell pwd)/../../target
-# We currently only support absolute paths.
-CARGO_TARGET_DIR	:= $(abspath $(CARGO_TARGET_DIR))
-
-# We are producing binaries here.
-EXAMPLE_TARGET_DIR      ?= $(CARGO_TARGET_DIR)/debug/c-examples/ffi
-
-EXAMPLES = keyserver configure
-CFLAGS  = -I../include -I../../openpgp-ffi/include -O0 -g -Wall -Werror
-LDFLAGS = -L$(CARGO_TARGET_DIR)/debug
-LDLIBS = -lsequoia_ffi
-
-# Prefix our target directory.
-TARGETS := $(foreach example,$(EXAMPLES),$(EXAMPLE_TARGET_DIR)/$(example))
-
-all: $(TARGETS)
-
-clean:
-	rm -f $(TARGETS)
-
-$(TARGETS): ../include/sequoia.h
-
-$(EXAMPLE_TARGET_DIR)/%: %.c
-	mkdir -p $(EXAMPLE_TARGET_DIR)
-	$(CC) $(CFLAGS) $(LDFLAGS) -o "$@" "$<" $(LDLIBS)
diff --git a/ffi/examples/configure.c b/ffi/examples/configure.c
deleted file mode 100644
index 6551e196..00000000
--- a/ffi/examples/configure.c
+++ /dev/null
@@ -1,51 +0,0 @@
-#define _GNU_SOURCE
-#include <assert.h>
-/* Roughly glibc compatible error reporting.  */
-#define error(S, E, F, ...) do {                        \
-  fprintf (stderr, (F), __VA_ARGS__);                   \
-  int s = (S), e = (E);                                 \
-  if (e) { fprintf (stderr, ": %s", strerror (e)); }    \
-  fprintf (stderr, "\n");                               \
-  fflush (stderr);                                      \
-  if (s) { exit (s); }                                  \
-  } while (0)
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <sequoia.h>
-
-int
-main (int argc, char **argv)
-{
-  pgp_error_t err;
-  sq_config_t cfg;
-  sq_context_t ctx;
-  sq_keyserver_t ks;
-
-  cfg = sq_context_configure ();
-  sq_config_home (cfg, "/tmp");
-  ctx = sq_config_build (cfg, &err);
-  if (ctx == NULL)
-    error (1, 0, "Initializing sequoia failed: %s",
-           pgp_error_to_string (err));
-
-  ks = sq_keyserver_keys_openpgp_org (ctx, SQ_NETWORK_POLICY_OFFLINE);
-  if (ks == NULL)
-    {
-      pgp_error_t err = sq_context_last_error (ctx);
-      assert (pgp_error_status (err) == PGP_STATUS_NETWORK_POLICY_VIOLATION);
-      char *msg = pgp_error_to_string (err);
-      error (0, 0, "Initializing KeyServer failed as expected: %s",
-             msg);
-      free (msg);
-      pgp_error_free (err);
-    }
-  else
-    assert (! "reachable");
-
-  sq_keyserver_free (ks);
-  sq_context_free (ctx);
-  return 0;
-}
diff --git a/ffi/examples/keyserver.c b/ffi/examples/keyserver.c
deleted file mode 100644
index 08624ea7..00000000
--- a/ffi/examples/keyserver.c
+++ /dev/null
@@ -1,56 +0,0 @@
-#define _GNU_SOURCE
-/* Roughly glibc compatible error reporting.  */
-#define error(S, E, F, ...) do {                        \
-  fprintf (stderr, (F), __VA_ARGS__);                   \
-  int s = (S), e = (E);                                 \
-  if (e) { fprintf (stderr, ": %s", strerror (e)); }    \
-  fprintf (stderr, "\n");                               \
-  fflush (stderr);                                      \
-  if (s) { exit (s); }                                  \
-  } while (0)
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <sequoia.h>
-
-int
-main (int argc, char **argv)
-{
-  pgp_error_t err;
-  sq_context_t ctx;
-  pgp_keyid_t id;
-  sq_keyserver_t ks;
-  pgp_cert_t cert;
-
-  ctx = sq_context_new (&err);
-  if (ctx == NULL)
-    error (1, 0, "Initializing sequoia failed: %s",
-           pgp_error_to_string (err));
-
-  ks = sq_keyserver_keys_openpgp_org (ctx, SQ_NETWORK_POLICY_ENCRYPTED);
-  if (ks == NULL)
-    {
-      pgp_error_t err = sq_context_last_error (ctx);
-      error (1, 0, "Initializing Keyserver failed: %s", pgp_error_to_string (err));
-    }
-
-  id = pgp_keyid_from_bytes ((uint8_t *) "\x24\x7F\x6D\xAB\xC8\x49\x14\xFE");
-  cert = sq_keyserver_get (ctx, ks, id);
-  if (cert == NULL)
-    {
-      pgp_error_t err = sq_context_last_error (ctx);
-      error (1, 0, "Failed to retrieve key: %s", pgp_error_to_string (err));
-    }
-
-  char *debug = pgp_cert_debug (cert);
-  printf ("%s", debug);
-  free (debug);
-
-  pgp_cert_free (cert);
-  pgp_keyid_free (id);
-  sq_keyserver_free (ks);
-  sq_context_free (ctx);
-  return 0;
-}
diff --git a/ffi/include/sequoia.h b/ffi/include/sequoia.h
deleted file mode 100644
index c32a2f3e..00000000
--- a/ffi/include/sequoia.h
+++ /dev/null
@@ -1,9 +0,0 @@
-#ifndef SEQUOIA_H
-#define SEQUOIA_H
-
-#include <sequoia/openpgp/error.h>
-#include <sequoia/core.h>
-#include <sequoia/openpgp.h>
-#include <sequoia/net.h>
-
-#endif
diff --git a/ffi/include/sequoia/core.h b/ffi/include/sequoia/core.h
deleted file mode 100644
index c73d54c1..00000000
--- a/ffi/include/sequoia/core.h
+++ /dev/null
@@ -1,172 +0,0 @@
-#ifndef SEQUOIA_CORE_H
-#define SEQUOIA_CORE_H
-
-#include <stddef.h>
-#include <stdint.h>
-#include <limits.h>
-#include <unistd.h>
-
-/* sequoia::Context.  */
-
-/*/
-/// A `struct sq_context *` is required for many operations.
-///
-/// # Example
-///
-/// ```c
-/// struct sq_context *ctx sq_context_new();
-/// if (ctx == NULL) { ... }
-/// ```
-/*/
-typedef struct sq_context *sq_context_t;
-
-/*/
-/// Returns the last error.
-///
-/// Returns and removes the last error from the context.
-/*/
-pgp_error_t sq_context_last_error (sq_context_t ctx);
-
-/*/
-/// Represents a `Context` configuration.
-/*/
-typedef struct sq_config *sq_config_t;
-
-/*/
-/// IPC policy for Sequoia.
-///
-/// With this policy you can control how Sequoia starts background
-/// servers.
-/*/
-typedef enum sq_ipc_policy {
-  /*/
-  /// External background servers only.
-  ///
-  /// We will always use external background servers.  If starting
-  /// one fails, the operation will fail.
-  ///
-  /// The advantage is that we never spawn a thread.
-  ///
-  /// The disadvantage is that we need to locate the background
-  /// server to start.  If you are distribute Sequoia with your
-  /// application, make sure to include the binaries, and to
-  /// configure the Context so that `context.lib()` points to the
-  /// directory containing the binaries.
-  /*/
-  SQ_IPC_POLICY_EXTERNAL = 0,
-
-  /*/
-  /// Internal background servers only.
-  ///
-  /// We will always use internal background servers.  It is very
-  /// unlikely that this fails.
-  ///
-  /// The advantage is that this method is very robust.  If you
-  /// distribute Sequoia with your application, you do not need to
-  /// ship the binary, and it does not matter what `context.lib()`
-  /// points to.  This is very robust and convenient.
-  ///
-  /// The disadvantage is that we spawn a thread in your
-  /// application.  Threads may play badly with `fork(2)`, file
-  /// handles, and locks.  If you are not doing anything fancy,
-  /// however, and only use fork-then-exec, you should be okay.
-  /*/
-  SQ_IPC_POLICY_INTERNAL = 1,
-
-  /*/
-  /// Prefer external, fall back to internal.
-  ///
-  /// We will first try to use an external background server, but
-  /// fall back on an internal one should that fail.
-  ///
-  /// The advantage is that if Sequoia is properly set up to find
-  /// the background servers, we will use these and get the
-  /// advantages of that approach.  Because we fail back on using an
-  /// internal server, we gain the robustness of that approach.
-  ///
-  /// The disadvantage is that we may or may not spawn a thread in
-  /// your application.  If this is unacceptable in your
-  /// environment, use the `External` policy.
-  /*/
-  SQ_IPC_POLICY_ROBUST = 2,
-
-  /* Dummy value to make sure the enumeration has a defined size.  Do
-     not use this value.  */
-  SQ_IPC_POLICY_FORCE_WIDTH = INT_MAX,
-} sq_ipc_policy_t;
-
-
-/*/
-/// Creates a Context with reasonable defaults.
-///
-/// Returns `NULL` on errors.  If `errp` is not `NULL`, the error is
-/// stored there.
-/*/
-sq_context_t sq_context_new(pgp_error_t *errp);
-
-/*/
-/// Frees a context.
-/*/
-void sq_context_free(sq_context_t context);
-
-/*/
-/// Creates a Context that can be configured.
-///
-/// The configuration is seeded like in `sq_context_new`, but can be
-/// modified.  A configuration has to be finalized using
-/// `sq_config_build()` in order to turn it into a Context.
-/*/
-sq_config_t sq_context_configure(void);
-
-/*/
-/// Returns the directory containing shared state.
-/*/
-const char *sq_context_home(const sq_context_t ctx);
-
-/*/
-/// Returns the directory containing backend servers.
-/*/
-const char *sq_context_lib(const sq_context_t ctx);
-
-/*/
-/// Returns the IPC policy.
-/*/
-sq_ipc_policy_t sq_context_ipc_policy(const sq_context_t ctx);
-
-/*/
-/// Returns whether or not this is an ephemeral context.
-/*/
-uint8_t sq_context_ephemeral(const sq_context_t ctx);
-
-
-/* sequoia::Config.  */
-
-/*/
-/// Finalizes the configuration and return a `Context`.
-///
-/// Consumes `cfg`.  Returns `NULL` on errors. Returns `NULL` on
-/// errors.  If `errp` is not `NULL`, the error is stored there.
-/*/
-sq_context_t sq_config_build(sq_config_t cfg, pgp_error_t *errp);
-
-/*/
-/// Sets the directory containing shared state.
-/*/
-void sq_config_home(sq_config_t cfg, const char *home);
-
-/*/
-/// Sets the directory containing backend servers.
-/*/
-void sq_config_lib(sq_config_t cfg, const char *lib);
-
-/*/
-/// Sets the IPC policy.
-/*/
-void sq_config_ipc_policy(sq_config_t cfg, sq_ipc_policy_t policy);
-
-/*/
-/// Makes this context ephemeral.
-/*/
-void sq_config_ephemeral(sq_config_t cfg);
-
-#endif
diff --git a/ffi/include/sequoia/net.h b/ffi/include/sequoia/net.h
deleted file mode 100644
index f1d850d3..00000000
--- a/ffi/include/sequoia/net.h
+++ /dev/null
@@ -1,99 +0,0 @@
-#ifndef SEQUOIA_NET_H
-#define SEQUOIA_NET_H
-
-#include <sequoia/core.h>
-
-/*/
-/// For accessing keyservers using HKP.
-/*/
-typedef struct sq_keyserver *sq_keyserver_t;
-
-/*/
-/// Network policy for Sequoia.
-///
-/// With this policy you can control how Sequoia accesses remote
-/// systems.
-/*/
-typedef enum sq_network_policy {
-  /* Do not contact remote systems.  */
-  SQ_NETWORK_POLICY_OFFLINE = 0,
-
-  /* Only contact remote systems using anonymization techniques like
-   * TOR.  */
-  SQ_NETWORK_POLICY_ANONYMIZED = 1,
-
-  /* Only contact remote systems using transports offering
-   * encryption and authentication like TLS.  */
-  SQ_NETWORK_POLICY_ENCRYPTED = 2,
-
-  /* Contact remote systems even with insecure transports.  */
-  SQ_NETWORK_POLICY_INSECURE = 3,
-
-  /* Dummy value to make sure the enumeration has a defined size.  Do
-     not use this value.  */
-  SQ_NETWORK_POLICY_FORCE_WIDTH = INT_MAX,
-} sq_network_policy_t;
-
-
-/*/
-/// Returns a handle for the given URI.
-///
-/// `uri` is a UTF-8 encoded value of a keyserver URI,
-/// e.g. `hkps://examle.org`.
-///
-/// Returns `NULL` on errors.
-/*/
-sq_keyserver_t sq_keyserver_new (sq_context_t ctx,
-				 sq_network_policy_t policy,
-				 const char *uri);
-
-/*/
-/// Returns a handle for the given URI.
-///
-/// `uri` is a UTF-8 encoded value of a keyserver URI,
-/// e.g. `hkps://examle.org`.  `cert` is a DER encoded certificate of
-/// size `len` used to authenticate the server.
-///
-/// Returns `NULL` on errors.
-/*/
-sq_keyserver_t sq_keyserver