summaryrefslogtreecommitdiffstats
path: root/g13/call-syshelp.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--g13/call-syshelp.c631
1 files changed, 631 insertions, 0 deletions
diff --git a/g13/call-syshelp.c b/g13/call-syshelp.c
new file mode 100644
index 0000000..b160ba3
--- /dev/null
+++ b/g13/call-syshelp.c
@@ -0,0 +1,631 @@
+/* call-syshelp.c - Communication with g13-syshelp
+ * Copyright (C) 2015 Werner Koch
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <time.h>
+#include <assert.h>
+#include <npth.h>
+
+#include "g13.h"
+#include <assuan.h>
+#include "../common/i18n.h"
+#include "g13tuple.h"
+#include "keyblob.h"
+#include "../common/membuf.h"
+#include "create.h"
+#include "call-syshelp.h"
+
+
+/* Local data for this module. A pointer to this is stored in the
+ CTRL object of each connection. */
+struct call_syshelp_s
+{
+ assuan_context_t assctx; /* The Assuan context for the current
+ g13-syshep connection. */
+};
+
+
+/* Parameter used with the CREATE command. */
+struct create_parm_s
+{
+ assuan_context_t ctx;
+ ctrl_t ctrl;
+ membuf_t plaintext;
+ unsigned int expect_plaintext:1;
+ unsigned int got_plaintext:1;
+};
+
+
+/* Parameter used with the MOUNT command. */
+struct mount_parm_s
+{
+ assuan_context_t ctx;
+ ctrl_t ctrl;
+ const void *keyblob;
+ size_t keybloblen;
+};
+
+
+
+
+
+/* Fork off the syshelp tool if this has not already been done. On
+ success stores the current Assuan context for the syshelp tool at
+ R_CTX. */
+static gpg_error_t
+start_syshelp (ctrl_t ctrl, assuan_context_t *r_ctx)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ assuan_fd_t no_close_list[3];
+ int i;
+
+ *r_ctx = NULL;
+
+ if (ctrl->syshelp_local && (*r_ctx = ctrl->syshelp_local->assctx))
+ return 0; /* Already set. */
+
+ if (opt.verbose)
+ log_info ("starting a new syshelp\n");
+
+ if (!ctrl->syshelp_local)
+ {
+ ctrl->syshelp_local = xtrycalloc (1, sizeof *ctrl->syshelp_local);
+ if (!ctrl->syshelp_local)
+ return gpg_error_from_syserror ();
+ }
+
+ if (es_fflush (NULL))
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error flushing pending output: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ i = 0;
+ if (log_get_fd () != -1)
+ no_close_list[i++] = assuan_fd_from_posix_fd (log_get_fd ());
+ no_close_list[i++] = assuan_fd_from_posix_fd (es_fileno (es_stderr));
+ no_close_list[i] = ASSUAN_INVALID_FD;
+
+ err = assuan_new (&ctx);
+ if (err)
+ {
+ log_error ("can't allocate assuan context: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ /* Call userv to start g13-syshelp. This userv script needs to be
+ * installed under the name "gnupg-g13-syshelp":
+ *
+ * if ( glob service-user root
+ * )
+ * reset
+ * suppress-args
+ * execute /home/wk/b/gnupg/g13/g13-syshelp -v
+ * else
+ * error Nothing to do for this service-user
+ * fi
+ * quit
+ */
+ {
+ const char *argv[4];
+
+ argv[0] = "userv";
+ argv[1] = "root";
+ argv[2] = "gnupg-g13-syshelp";
+ argv[3] = NULL;
+
+ err = assuan_pipe_connect (ctx, "/usr/bin/userv", argv,
+ no_close_list, NULL, NULL, 0);
+ }
+ if (err)
+ {
+ log_error ("can't connect to '%s': %s %s\n",
+ "g13-syshelp", gpg_strerror (err), gpg_strsource (err));
+ log_info ("(is userv and its gnupg-g13-syshelp script installed?)\n");
+ assuan_release (ctx);
+ return err;
+ }
+
+ *r_ctx = ctrl->syshelp_local->assctx = ctx;
+
+ if (DBG_IPC)
+ log_debug ("connection to g13-syshelp established\n");
+
+ return 0;
+}
+
+
+/* Release local resources associated with CTRL. */
+void
+call_syshelp_release (ctrl_t ctrl)
+{
+ if (!ctrl)
+ return;
+ if (ctrl->syshelp_local)
+ {
+ assuan_release (ctrl->syshelp_local->assctx);
+ ctrl->syshelp_local->assctx = NULL;
+ xfree (ctrl->syshelp_local);
+ ctrl->syshelp_local = NULL;
+ }
+}
+
+
+
+/* Staus callback for call_syshelp_find_device. */
+static gpg_error_t
+finddevice_status_cb (void *opaque, const char *line)
+{
+ char **r_blockdev = opaque;
+ char *p;
+
+ if ((p = has_leading_keyword (line, "BLOCKDEV")) && *p && !*r_blockdev)
+ {
+ *r_blockdev = xtrystrdup (p);
+ if (!*r_blockdev)
+ return gpg_error_from_syserror ();
+ }
+
+ return 0;
+}
+
+
+/* Send the FINDDEVICE command to the syshelper. On success the name
+ * of the block device is stored at R_BLOCKDEV. */
+gpg_error_t
+call_syshelp_find_device (ctrl_t ctrl, const char *name, char **r_blockdev)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ char *line = NULL;
+ char *blockdev = NULL; /* The result. */
+
+ *r_blockdev = NULL;
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ line = xtryasprintf ("FINDDEVICE %s", name);
+ if (!line)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ err = assuan_transact (ctx, line, NULL, NULL, NULL, NULL,
+ finddevice_status_cb, &blockdev);
+ if (err)
+ goto leave;
+ if (!blockdev)
+ {
+ log_error ("status line for successful FINDDEVICE missing\n");
+ err = gpg_error (GPG_ERR_UNEXPECTED);
+ goto leave;
+ }
+ *r_blockdev = blockdev;
+ blockdev = NULL;
+
+ leave:
+ xfree (blockdev);
+ xfree (line);
+ return err;
+}
+
+
+
+static gpg_error_t
+getkeyblob_data_cb (void *opaque, const void *data, size_t datalen)
+{
+ membuf_t *mb = opaque;
+
+ if (data)
+ put_membuf (mb, data, datalen);
+
+ return 0;
+}
+
+
+/* Send the GTEKEYBLOB command to the syshelper. On success the
+ * encrypted keyblpob is stored at (R_ENCKEYBLOB,R_ENCKEYBLOBLEN). */
+gpg_error_t
+call_syshelp_get_keyblob (ctrl_t ctrl,
+ void **r_enckeyblob, size_t *r_enckeybloblen)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ membuf_t mb;
+
+ *r_enckeyblob = NULL;
+ *r_enckeybloblen = 0;
+ init_membuf (&mb, 512);
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ err = assuan_transact (ctx, "GETKEYBLOB",
+ getkeyblob_data_cb, &mb,
+ NULL, NULL, NULL, NULL);
+ if (err)
+ goto leave;
+ *r_enckeyblob = get_membuf (&mb, r_enckeybloblen);
+ if (!*r_enckeyblob)
+ err = gpg_error_from_syserror ();
+
+ leave:
+ xfree (get_membuf (&mb, NULL));
+ return err;
+}
+
+
+
+/* Send the DEVICE command to the syshelper. FNAME is the name of the
+ device. */
+gpg_error_t
+call_syshelp_set_device (ctrl_t ctrl, const char *fname)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ char *line = NULL;
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ line = xtryasprintf ("DEVICE %s", fname);
+ if (!line)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ err = assuan_transact (ctx, line, NULL, NULL, NULL, NULL, NULL, NULL);
+
+ leave:
+ xfree (line);
+ return err;
+}
+
+
+
+static gpg_error_t
+create_status_cb (void *opaque, const char *line)
+{
+ struct create_parm_s *parm = opaque;
+
+ if (has_leading_keyword (line, "PLAINTEXT_FOLLOWS"))
+ parm->expect_plaintext = 1;
+
+ return 0;
+}
+
+
+static gpg_error_t
+create_data_cb (void *opaque, const void *data, size_t datalen)
+{
+ struct create_parm_s *parm = opaque;
+ gpg_error_t err = 0;
+
+ if (!parm->expect_plaintext)
+ {
+ log_error ("status line for data missing\n");
+ err = gpg_error (GPG_ERR_UNEXPECTED);
+ }
+ else if (data)
+ {
+ put_membuf (&parm->plaintext, data, datalen);
+ }
+ else
+ {
+ parm->expect_plaintext = 0;
+ parm->got_plaintext = 1;
+ }
+
+ return err;
+}
+
+
+static gpg_error_t
+create_inq_cb (void *opaque, const char *line)
+{
+ struct create_parm_s *parm = opaque;
+ gpg_error_t err;
+
+ if (has_leading_keyword (line, "ENCKEYBLOB"))
+ {
+ void *plaintext;
+ size_t plaintextlen;
+
+ if (!parm->got_plaintext)
+ err = gpg_error (GPG_ERR_UNEXPECTED);
+ else if (!(plaintext = get_membuf (&parm->plaintext, &plaintextlen)))
+ err = gpg_error_from_syserror ();
+ else
+ {
+ void *ciphertext;
+ size_t ciphertextlen;
+
+ log_printhex (plaintext, plaintextlen, "plain");
+ err = g13_encrypt_keyblob (parm->ctrl,
+ plaintext, plaintextlen,
+ &ciphertext, &ciphertextlen);
+ wipememory (plaintext, plaintextlen);
+ xfree (plaintext);
+ if (err)
+ log_error ("error encrypting keyblob: %s\n", gpg_strerror (err));
+ else
+ {
+ err = assuan_send_data (parm->ctx, ciphertext, ciphertextlen);
+ xfree (ciphertext);
+ if (err)
+ log_error ("sending ciphertext to g13-syshelp failed: %s\n",
+ gpg_strerror (err));
+ }
+ }
+ }
+ else
+ err = gpg_error (GPG_ERR_ASS_UNKNOWN_INQUIRE);
+
+ return err;
+}
+
+
+/* Run the CREATE command on the current device. CONTTYPES gives the
+ requested content type for the new container. */
+gpg_error_t
+call_syshelp_run_create (ctrl_t ctrl, int conttype)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ struct create_parm_s parm;
+
+ memset (&parm, 0, sizeof parm);
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ /* tty_get ("waiting for debugger"); */
+ /* tty_kill_prompt (); */
+
+ parm.ctx = ctx;
+ parm.ctrl = ctrl;
+ init_membuf (&parm.plaintext, 512);
+ if (conttype == CONTTYPE_DM_CRYPT)
+ {
+ err = assuan_transact (ctx, "CREATE dm-crypt",
+ create_data_cb, &parm,
+ create_inq_cb, &parm,
+ create_status_cb, &parm);
+ }
+ else
+ {
+ log_error ("invalid backend type %d given\n", conttype);
+ err = GPG_ERR_INTERNAL;
+ goto leave;
+ }
+
+ leave:
+ xfree (get_membuf (&parm.plaintext, NULL));
+ return err;
+}
+
+
+
+static gpg_error_t
+mount_status_cb (void *opaque, const char *line)
+{
+ struct mount_parm_s *parm = opaque;
+
+ /* Nothing right now. */
+ (void)parm;
+ (void)line;
+
+ return 0;
+}
+
+
+/* Inquire callback for MOUNT and RESUME. */
+static gpg_error_t
+mount_inq_cb (void *opaque, const char *line)
+{
+ struct mount_parm_s *parm = opaque;
+ gpg_error_t err;
+
+ if (has_leading_keyword (line, "KEYBLOB"))
+ {
+ int setconfidential = !assuan_get_flag (parm->ctx, ASSUAN_CONFIDENTIAL);
+
+ if (setconfidential)
+ assuan_begin_confidential (parm->ctx);
+ err = assuan_send_data (parm->ctx, parm->keyblob, parm->keybloblen);
+ if (setconfidential)
+ assuan_end_confidential (parm->ctx);
+ if (err)
+ log_error ("sending keyblob to g13-syshelp failed: %s\n",
+ gpg_strerror (err));
+ }
+ else
+ err = gpg_error (GPG_ERR_ASS_UNKNOWN_INQUIRE);
+
+ return err;
+}
+
+
+/*
+ * Run the MOUNT command on the current device. CONTTYPES gives the
+ * requested content type for the new container. MOUNTPOINT the
+ * desired mount point or NULL for default.
+ */
+gpg_error_t
+call_syshelp_run_mount (ctrl_t ctrl, int conttype, const char *mountpoint,
+ tupledesc_t tuples)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ struct mount_parm_s parm;
+
+ memset (&parm, 0, sizeof parm);
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ /* tty_get ("waiting for debugger"); */
+ /* tty_kill_prompt (); */
+
+ parm.ctx = ctx;
+ parm.ctrl = ctrl;
+ if (conttype == CONTTYPE_DM_CRYPT)
+ {
+ ref_tupledesc (tuples);
+ parm.keyblob = get_tupledesc_data (tuples, &parm.keybloblen);
+ err = assuan_transact (ctx, "MOUNT dm-crypt",
+ NULL, NULL,
+ mount_inq_cb, &parm,
+ mount_status_cb, &parm);
+ unref_tupledesc (tuples);
+ }
+ else
+ {
+ (void)mountpoint; /* Not used. */
+ log_error ("invalid backend type %d given\n", conttype);
+ err = GPG_ERR_INTERNAL;
+ goto leave;
+ }
+
+ leave:
+ return err;
+}
+
+
+
+/*
+ * Run the UMOUNT command on the current device. CONTTYPES gives the
+ * content type of the container (fixme: Do we really need this?).
+ */
+gpg_error_t
+call_syshelp_run_umount (ctrl_t ctrl, int conttype)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ if (conttype == CONTTYPE_DM_CRYPT)
+ {
+ err = assuan_transact (ctx, "UMOUNT dm-crypt",
+ NULL, NULL,
+ NULL, NULL,
+ NULL, NULL);
+ }
+ else
+ {
+ log_error ("invalid backend type %d given\n", conttype);
+ err = GPG_ERR_INTERNAL;
+ goto leave;
+ }
+
+ leave:
+ return err;
+}
+
+
+
+/*
+ * Run the SUSPEND command on the current device. CONTTYPES gives the
+ * requested content type for the new container.
+ */
+gpg_error_t
+call_syshelp_run_suspend (ctrl_t ctrl, int conttype)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ if (conttype == CONTTYPE_DM_CRYPT)
+ {
+ err = assuan_transact (ctx, "SUSPEND dm-crypt",
+ NULL, NULL,
+ NULL, NULL,
+ NULL, NULL);
+ }
+ else
+ {
+ log_error ("invalid backend type %d given\n", conttype);
+ err = GPG_ERR_INTERNAL;
+ goto leave;
+ }
+
+ leave:
+ return err;
+}
+
+
+
+/* Run the RESUME command on the current device. CONTTYPES gives the
+ requested content type for the container. */
+gpg_error_t
+call_syshelp_run_resume (ctrl_t ctrl, int conttype, tupledesc_t tuples)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ struct mount_parm_s parm;
+
+ memset (&parm, 0, sizeof parm);
+
+ err = start_syshelp (ctrl, &ctx);
+ if (err)
+ goto leave;
+
+ /* tty_get ("waiting for debugger"); */
+ /* tty_kill_prompt (); */
+
+ parm.ctx = ctx;
+ parm.ctrl = ctrl;
+ if (conttype == CONTTYPE_DM_CRYPT)
+ {
+ ref_tupledesc (tuples);
+ parm.keyblob = get_tupledesc_data (tuples, &parm.keybloblen);
+ err = assuan_transact (ctx, "RESUME dm-crypt",
+ NULL, NULL,
+ mount_inq_cb, &parm,
+ NULL, NULL);
+ unref_tupledesc (tuples);
+ }
+ else
+ {
+ log_error ("invalid backend type %d given\n", conttype);
+ err = GPG_ERR_INTERNAL;
+ goto leave;
+ }
+
+ leave:
+ return err;
+}