implement RFE 3239, 'Remove "Content-Disposition: attachment" from PGP/MIME signed...
[claws.git] / src / plugins / pgpmime / pgpmime.c
index fe0793daac9f98e41eadc38dc7c0d607632cba5a..b9a3d7dfef5ebda13768ee662e833214da36d350 100644 (file)
@@ -1,10 +1,10 @@
 /*
- * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
- * Copyright (C) 1999-2003 Hiroyuki Yamamoto & the Sylpheed-Claws team
+ * Claws Mail -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2014 the Claws Mail team
  *
  * This program 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 2 of the License, or
+ * the Free Software Foundation; either version 3 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ * 
  */
 
 #ifdef HAVE_CONFIG_H
 #  include "config.h"
+#include "claws-features.h"
 #endif
 
 #ifdef USE_GPGME
 
 #include "defs.h"
 #include <glib.h>
+#include <glib/gi18n.h>
 #include <gpgme.h>
+#include <ctype.h>
+#include <errno.h>
 
 #include "utils.h"
 #include "privacy.h"
 #include "procmime.h"
+#include "plugin.h"
+
 #include "pgpmime.h"
-#include "sgpgme.h"
+#include <plugins/pgpcore/sgpgme.h>
+#include <plugins/pgpcore/prefs_gpg.h>
+#include <plugins/pgpcore/passphrase.h>
+#include <plugins/pgpcore/pgp_utils.h>
+
 #include "prefs_common.h"
 
 typedef struct _PrivacyDataPGP PrivacyDataPGP;
@@ -42,8 +52,8 @@ struct _PrivacyDataPGP
        
        gboolean        done_sigtest;
        gboolean        is_signed;
-       GpgmeSigStat    sigstatus;
-       GpgmeCtx        ctx;
+       gpgme_verify_result_t   sigstatus;
+       gpgme_ctx_t     ctx;
 };
 
 static PrivacySystem pgpmime_system;
@@ -53,13 +63,17 @@ static gint pgpmime_check_signature(MimeInfo *mimeinfo);
 static PrivacyDataPGP *pgpmime_new_privacydata()
 {
        PrivacyDataPGP *data;
+       gpgme_error_t err;
 
        data = g_new0(PrivacyDataPGP, 1);
        data->data.system = &pgpmime_system;
        data->done_sigtest = FALSE;
        data->is_signed = FALSE;
-       data->sigstatus = GPGME_SIG_STAT_NONE;
-       gpgme_new(&data->ctx);
+       data->sigstatus = NULL;
+       if ((err = gpgme_new(&data->ctx)) != GPG_ERR_NO_ERROR) {
+               g_warning(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               return NULL;
+       }
        
        return data;
 }
@@ -67,7 +81,7 @@ static PrivacyDataPGP *pgpmime_new_privacydata()
 static void pgpmime_free_privacydata(PrivacyData *_data)
 {
        PrivacyDataPGP *data = (PrivacyDataPGP *) _data;
-       
+       gpgme_release(data->ctx);
        g_free(data);
 }
 
@@ -78,7 +92,7 @@ static gboolean pgpmime_is_signed(MimeInfo *mimeinfo)
        const gchar *protocol;
        PrivacyDataPGP *data = NULL;
        
-       g_return_val_if_fail(mimeinfo != NULL, FALSE);
+       cm_return_val_if_fail(mimeinfo != NULL, FALSE);
        if (mimeinfo->privacy != NULL) {
                data = (PrivacyDataPGP *) mimeinfo->privacy;
                if (data->done_sigtest)
@@ -90,10 +104,11 @@ static gboolean pgpmime_is_signed(MimeInfo *mimeinfo)
        if (parent == NULL)
                return FALSE;
        if ((parent->type != MIMETYPE_MULTIPART) ||
-           g_strcasecmp(parent->subtype, "signed"))
+           g_ascii_strcasecmp(parent->subtype, "signed"))
                return FALSE;
        protocol = procmime_mimeinfo_get_parameter(parent, "protocol");
-       if ((protocol == NULL) || g_strcasecmp(protocol, "application/pgp-signature"))
+       if ((protocol == NULL) || 
+           (g_ascii_strcasecmp(protocol, "application/pgp-signature")))
                return FALSE;
 
        /* check if mimeinfo is the first child */
@@ -106,50 +121,34 @@ static gboolean pgpmime_is_signed(MimeInfo *mimeinfo)
        if (signature == NULL)
                return FALSE;
        if ((signature->type != MIMETYPE_APPLICATION) ||
-           g_strcasecmp(signature->subtype, "pgp-signature"))
+           (g_ascii_strcasecmp(signature->subtype, "pgp-signature")))
                return FALSE;
 
        if (data == NULL) {
                data = pgpmime_new_privacydata();
                mimeinfo->privacy = (PrivacyData *) data;
        }
-       data->done_sigtest = TRUE;
-       data->is_signed = TRUE;
+       if (data != NULL) {
+               data->done_sigtest = TRUE;
+               data->is_signed = TRUE;
+       }
 
-       if (prefs_common.auto_check_signatures)
-               pgpmime_check_signature(mimeinfo);
-       
        return TRUE;
 }
 
-static gint pgpmime_check_signature(MimeInfo *mimeinfo)
+static gchar *get_canonical_content(FILE *fp, const gchar *boundary)
 {
-       PrivacyDataPGP *data;
-       MimeInfo *parent, *signature;
-       FILE *fp;
+       gchar *ret;
+       GString *textbuffer;
+       guint boundary_len;
        gchar buf[BUFFSIZE];
-       gchar *boundary;
-       GString *textstr;
-       gint boundary_len;
-       GpgmeData sigdata, textdata;
-       
-       g_return_val_if_fail(mimeinfo != NULL, -1);
-       g_return_val_if_fail(mimeinfo->privacy != NULL, -1);
-       data = (PrivacyDataPGP *) mimeinfo->privacy;
-       
-       debug_print("Checking PGP/MIME signature\n");
-       parent = procmime_mimeinfo_parent(mimeinfo);
 
-       fp = fopen(parent->filename, "rb");
-       g_return_val_if_fail(fp != NULL, SIGNATURE_INVALID);
-       
-       boundary = g_hash_table_lookup(parent->parameters, "boundary");
        boundary_len = strlen(boundary);
        while (fgets(buf, sizeof(buf), fp) != NULL)
                if (IS_BOUNDARY(buf, boundary, boundary_len))
                        break;
 
-       textstr = g_string_new("");
+       textbuffer = g_string_new("");
        while (fgets(buf, sizeof(buf), fp) != NULL) {
                gchar *buf2;
 
@@ -157,21 +156,81 @@ static gint pgpmime_check_signature(MimeInfo *mimeinfo)
                        break;
                
                buf2 = canonicalize_str(buf);
-               g_string_append(textstr, buf2);
+               g_string_append(textbuffer, buf2);
                g_free(buf2);
        }
-       g_string_truncate(textstr, textstr->len - 2);
+       g_string_truncate(textbuffer, textbuffer->len - 2);
                
-       gpgme_data_new_from_mem(&textdata, textstr->str, textstr->len, 0);
+       ret = textbuffer->str;
+       g_string_free(textbuffer, FALSE);
+
+       return ret;
+}
+
+static gint pgpmime_check_signature(MimeInfo *mimeinfo)
+{
+       PrivacyDataPGP *data;
+       MimeInfo *parent, *signature;
+       FILE *fp;
+       gchar *boundary;
+       gchar *textstr;
+       gpgme_data_t sigdata = NULL, textdata = NULL;
+       gpgme_error_t err;
+       cm_return_val_if_fail(mimeinfo != NULL, -1);
+       cm_return_val_if_fail(mimeinfo->privacy != NULL, -1);
+       data = (PrivacyDataPGP *) mimeinfo->privacy;
+       if ((err = gpgme_new(&data->ctx)) != GPG_ERR_NO_ERROR) {
+               debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               return 0;
+       }
+
+       
+       debug_print("Checking PGP/MIME signature\n");
+
+       err = gpgme_set_protocol(data->ctx, GPGME_PROTOCOL_OpenPGP);
+
+       if (err) {
+               debug_print ("gpgme_set_protocol failed: %s\n",
+                   gpgme_strerror (err));
+       }
+       parent = procmime_mimeinfo_parent(mimeinfo);
+
+       fp = g_fopen(parent->data.filename, "rb");
+       cm_return_val_if_fail(fp != NULL, SIGNATURE_INVALID);
+       
+       boundary = g_hash_table_lookup(parent->typeparameters, "boundary");
+       if (!boundary) {
+               privacy_set_error(_("Signature boundary not found."));
+               fclose(fp);
+               return 0;
+       }
+       textstr = get_canonical_content(fp, boundary);
+
+       err = gpgme_data_new_from_mem(&textdata, textstr, (size_t)strlen(textstr), 0);
+       if (err) {
+               debug_print ("gpgme_data_new_from_mem failed: %s\n",
+                   gpgme_strerror (err));
+       }
        signature = (MimeInfo *) mimeinfo->node->next->data;
        sigdata = sgpgme_data_from_mimeinfo(signature);
 
-       data->sigstatus =
-               sgpgme_verify_signature (data->ctx, sigdata, textdata);
+       err = 0;
+       if (signature->encoding_type == ENC_BASE64) {
+               err = gpgme_data_set_encoding (sigdata, GPGME_DATA_ENCODING_BASE64);
+       }
        
+       if (err) {
+               debug_print ("gpgme_data_set_encoding failed: %s\n",
+                       gpgme_strerror (err));
+       }
+
+       data->sigstatus =
+               sgpgme_verify_signature (data->ctx, sigdata, textdata, NULL);
+
        gpgme_data_release(sigdata);
        gpgme_data_release(textdata);
-       g_string_free(textstr, TRUE);
+       g_free(textstr);
        fclose(fp);
        
        return 0;
@@ -181,7 +240,7 @@ static SignatureStatus pgpmime_get_sig_status(MimeInfo *mimeinfo)
 {
        PrivacyDataPGP *data = (PrivacyDataPGP *) mimeinfo->privacy;
        
-       g_return_val_if_fail(data != NULL, SIGNATURE_INVALID);
+       cm_return_val_if_fail(data != NULL, SIGNATURE_INVALID);
 
        return sgpgme_sigstat_gpgme_to_privacy(data->ctx, data->sigstatus);
 }
@@ -190,7 +249,7 @@ static gchar *pgpmime_get_sig_info_short(MimeInfo *mimeinfo)
 {
        PrivacyDataPGP *data = (PrivacyDataPGP *) mimeinfo->privacy;
        
-       g_return_val_if_fail(data != NULL, g_strdup("Error"));
+       cm_return_val_if_fail(data != NULL, g_strdup("Error"));
 
        return sgpgme_sigstat_info_short(data->ctx, data->sigstatus);
 }
@@ -198,8 +257,8 @@ static gchar *pgpmime_get_sig_info_short(MimeInfo *mimeinfo)
 static gchar *pgpmime_get_sig_info_full(MimeInfo *mimeinfo)
 {
        PrivacyDataPGP *data = (PrivacyDataPGP *) mimeinfo->privacy;
-       
-       g_return_val_if_fail(data != NULL, g_strdup("Error"));
+
+       cm_return_val_if_fail(data != NULL, g_strdup("Error"));
 
        return sgpgme_sigstat_info_full(data->ctx, data->sigstatus);
 }
@@ -208,13 +267,16 @@ static gboolean pgpmime_is_encrypted(MimeInfo *mimeinfo)
 {
        MimeInfo *tmpinfo;
        const gchar *tmpstr;
-       
+       const gchar *begin_indicator = "-----BEGIN PGP MESSAGE-----";
+       const gchar *end_indicator = "-----END PGP MESSAGE-----";
+       gchar *textdata;
+
        if (mimeinfo->type != MIMETYPE_MULTIPART)
                return FALSE;
-       if (g_strcasecmp(mimeinfo->subtype, "encrypted"))
+       if (g_ascii_strcasecmp(mimeinfo->subtype, "encrypted"))
                return FALSE;
        tmpstr = procmime_mimeinfo_get_parameter(mimeinfo, "protocol");
-       if ((tmpstr == NULL) || g_strcasecmp(tmpstr, "application/pgp-encrypted"))
+       if ((tmpstr == NULL) || g_ascii_strcasecmp(tmpstr, "application/pgp-encrypted"))
                return FALSE;
        if (g_node_n_children(mimeinfo->node) != 2)
                return FALSE;
@@ -222,77 +284,472 @@ static gboolean pgpmime_is_encrypted(MimeInfo *mimeinfo)
        tmpinfo = (MimeInfo *) g_node_nth_child(mimeinfo->node, 0)->data;
        if (tmpinfo->type != MIMETYPE_APPLICATION)
                return FALSE;
-       if (g_strcasecmp(tmpinfo->subtype, "pgp-encrypted"))
+       if (g_ascii_strcasecmp(tmpinfo->subtype, "pgp-encrypted"))
                return FALSE;
        
        tmpinfo = (MimeInfo *) g_node_nth_child(mimeinfo->node, 1)->data;
        if (tmpinfo->type != MIMETYPE_APPLICATION)
                return FALSE;
-       if (g_strcasecmp(tmpinfo->subtype, "octet-stream"))
+       if (g_ascii_strcasecmp(tmpinfo->subtype, "octet-stream"))
+               return FALSE;
+       
+       textdata = get_part_as_string(tmpinfo);
+       if (!textdata)
                return FALSE;
        
+       if (!pgp_locate_armor_header(textdata, begin_indicator)) {
+               g_free(textdata);
+               return FALSE;
+       }
+       if (!pgp_locate_armor_header(textdata, end_indicator)) {
+               g_free(textdata);
+               return FALSE;
+       }
+
+       g_free(textdata);
+
        return TRUE;
 }
 
 static MimeInfo *pgpmime_decrypt(MimeInfo *mimeinfo)
 {
        MimeInfo *encinfo, *decinfo, *parseinfo;
-       GpgmeData cipher, plain;
+       gpgme_data_t cipher = NULL, plain = NULL;
        static gint id = 0;
        FILE *dstfp;
-       gint nread;
        gchar *fname;
-       gchar buf[BUFFSIZE];
+       gpgme_verify_result_t sigstat = NULL;
+       PrivacyDataPGP *data = NULL;
+       gpgme_ctx_t ctx;
+       gchar *chars;
+       size_t len;
+       gpgme_error_t err;
+
+       if ((err = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR) {
+               debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               return NULL;
+       }
        
-       g_return_val_if_fail(pgpmime_is_encrypted(mimeinfo), NULL);
+       cm_return_val_if_fail(pgpmime_is_encrypted(mimeinfo), NULL);
        
        encinfo = (MimeInfo *) g_node_nth_child(mimeinfo->node, 1)->data;
 
        cipher = sgpgme_data_from_mimeinfo(encinfo);
-       plain = sgpgme_decrypt(cipher);
+       plain = sgpgme_decrypt_verify(cipher, &sigstat, ctx);
+
        gpgme_data_release(cipher);
-       if (plain == NULL)
+       if (plain == NULL) {
+               debug_print("plain is null!\n");
+               gpgme_release(ctx);
                return NULL;
-       
+       }
+
        fname = g_strdup_printf("%s%cplaintext.%08x",
                get_mime_tmp_dir(), G_DIR_SEPARATOR, ++id);
 
-       if ((dstfp = fopen(fname, "wb")) == NULL) {
+       if ((dstfp = g_fopen(fname, "wb")) == NULL) {
                FILE_OP_ERROR(fname, "fopen");
+               privacy_set_error(_("Couldn't open decrypted file %s"), fname);
                g_free(fname);
                gpgme_data_release(plain);
+               gpgme_release(ctx);
+               debug_print("can't open!\n");
                return NULL;
        }
 
-       fprintf(dstfp, "MIME-Version: 1.0\n");
-       gpgme_data_rewind (plain);
-       while (gpgme_data_read(plain, buf, sizeof(buf), &nread) == GPGME_No_Error) {
-               fwrite (buf, nread, 1, dstfp);
+       if (fprintf(dstfp, "MIME-Version: 1.0\n") < 0) {
+               FILE_OP_ERROR(fname, "fprintf");
+               fclose(dstfp);
+               privacy_set_error(_("Couldn't write to decrypted file %s"), fname);
+               g_free(fname);
+               gpgme_data_release(plain);
+               gpgme_release(ctx);
+               debug_print("can't open!\n");
+               return NULL;
+       }
+
+       chars = sgpgme_data_release_and_get_mem(plain, &len);
+       if (len > 0) {
+               if (fwrite(chars, 1, len, dstfp) < len) {
+                       FILE_OP_ERROR(fname, "fwrite");
+                       g_free(chars);
+                       fclose(dstfp);
+                       privacy_set_error(_("Couldn't write to decrypted file %s"), fname);
+                       g_free(fname);
+                       gpgme_data_release(plain);
+                       gpgme_release(ctx);
+                       debug_print("can't open!\n");
+                       return NULL;
+               }
+       }
+       g_free(chars);
+
+       if (fclose(dstfp) == EOF) {
+               FILE_OP_ERROR(fname, "fclose");
+               privacy_set_error(_("Couldn't close decrypted file %s"), fname);
+               g_free(fname);
+               gpgme_data_release(plain);
+               gpgme_release(ctx);
+               debug_print("can't open!\n");
+               return NULL;
        }
-       fclose(dstfp);
-       
-       gpgme_data_release(plain);
 
        parseinfo = procmime_scan_file(fname);
        g_free(fname);
-       if (parseinfo == NULL)
+       if (parseinfo == NULL) {
+               gpgme_release(ctx);
+               privacy_set_error(_("Couldn't parse decrypted file."));
                return NULL;
+       }
        decinfo = g_node_first_child(parseinfo->node) != NULL ?
                g_node_first_child(parseinfo->node)->data : NULL;
-       if (decinfo == NULL)
+       if (decinfo == NULL) {
+               privacy_set_error(_("Couldn't parse decrypted file parts."));
+               gpgme_release(ctx);
                return NULL;
+       }
 
        g_node_unlink(decinfo->node);
        procmime_mimeinfo_free_all(parseinfo);
 
-       decinfo->tmpfile = TRUE;
-       
+       decinfo->tmp = TRUE;
+
+       if (sigstat != NULL && sigstat->signatures != NULL) {
+               if (decinfo->privacy != NULL) {
+                       data = (PrivacyDataPGP *) decinfo->privacy;
+               } else {
+                       data = pgpmime_new_privacydata();
+                       decinfo->privacy = (PrivacyData *) data;        
+               }
+               if (data != NULL) {
+                       data->done_sigtest = TRUE;
+                       data->is_signed = TRUE;
+                       data->sigstatus = sigstat;
+                       if (data->ctx)
+                               gpgme_release(data->ctx);
+                       data->ctx = ctx;
+               }
+       } else
+               gpgme_release(ctx);
+
        return decinfo;
 }
 
+gboolean pgpmime_sign(MimeInfo *mimeinfo, PrefsAccount *account, const gchar *from_addr)
+{
+       MimeInfo *msgcontent, *sigmultipart, *newinfo;
+       gchar *textstr, *micalg = NULL;
+       FILE *fp;
+       gchar *boundary = NULL;
+       gchar *sigcontent;
+       gpgme_ctx_t ctx;
+       gpgme_data_t gpgtext, gpgsig;
+       gpgme_error_t err;
+       size_t len;
+       struct passphrase_cb_info_s info;
+       gpgme_sign_result_t result = NULL;
+       gchar *test_msg;
+       
+       fp = my_tmpfile();
+       if (fp == NULL) {
+               privacy_set_error(_("Couldn't create temporary file: %s"), strerror(errno));
+               return FALSE;
+       }
+       procmime_write_mimeinfo(mimeinfo, fp);
+       rewind(fp);
+
+       /* read temporary file into memory */
+       test_msg = file_read_stream_to_str(fp);
+       fclose(fp);
+       
+       memset (&info, 0, sizeof info);
+
+       /* remove content node from message */
+       msgcontent = (MimeInfo *) mimeinfo->node->children->data;
+       g_node_unlink(msgcontent->node);
+
+       /* create temporary multipart for content */
+       sigmultipart = procmime_mimeinfo_new();
+       sigmultipart->type = MIMETYPE_MULTIPART;
+       sigmultipart->subtype = g_strdup("signed");
+       
+       do {
+               g_free(boundary);
+               boundary = generate_mime_boundary("Sig");
+       } while (strstr(test_msg, boundary) != NULL);
+       
+       g_free(test_msg);
+
+       g_hash_table_insert(sigmultipart->typeparameters, g_strdup("boundary"),
+                            g_strdup(boundary));
+       g_hash_table_insert(sigmultipart->typeparameters, g_strdup("protocol"),
+                            g_strdup("application/pgp-signature"));
+       g_node_append(sigmultipart->node, msgcontent->node);
+       g_node_append(mimeinfo->node, sigmultipart->node);
+
+       /* write message content to temporary file */
+       fp = my_tmpfile();
+       if (fp == NULL) {
+               perror("my_tmpfile");
+               privacy_set_error(_("Couldn't create temporary file: %s"), strerror(errno));
+               return FALSE;
+       }
+       procmime_write_mimeinfo(sigmultipart, fp);
+       rewind(fp);
+
+       /* read temporary file into memory */
+       textstr = get_canonical_content(fp, boundary);
+
+       fclose(fp);
+
+       gpgme_data_new_from_mem(&gpgtext, textstr, (size_t)strlen(textstr), 0);
+       gpgme_data_new(&gpgsig);
+       if ((err = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR) {
+               debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               return FALSE;
+       }
+       gpgme_set_textmode(ctx, 1);
+       gpgme_set_armor(ctx, 1);
+       gpgme_signers_clear (ctx);
+
+       if (!sgpgme_setup_signers(ctx, account, from_addr)) {
+               gpgme_release(ctx);
+               return FALSE;
+       }
+
+       prefs_gpg_enable_agent(prefs_gpg_get_config()->use_gpg_agent);
+       if (getenv("GPG_AGENT_INFO") && prefs_gpg_get_config()->use_gpg_agent) {
+               debug_print("GPG_AGENT_INFO environment defined, running without passphrase callback\n");
+       } else {
+               info.c = ctx;
+               gpgme_set_passphrase_cb (ctx, gpgmegtk_passphrase_cb, &info);
+       }
+
+       err = gpgme_op_sign(ctx, gpgtext, gpgsig, GPGME_SIG_MODE_DETACH);
+       if (err != GPG_ERR_NO_ERROR) {
+               if (err == GPG_ERR_CANCELED) {
+                       /* ignore cancelled signing */
+                       privacy_reset_error();
+                       debug_print("gpgme_op_sign cancelled\n");
+               } else {
+                       privacy_set_error(_("Data signing failed, %s"), gpgme_strerror(err));
+                       debug_print("gpgme_op_sign error : %x\n", err);
+               }
+               gpgme_release(ctx);
+               return FALSE;
+       }
+       result = gpgme_op_sign_result(ctx);
+       if (result && result->signatures) {
+               gpgme_new_signature_t sig = result->signatures;
+               if (gpgme_get_protocol(ctx) == GPGME_PROTOCOL_OpenPGP) {
+                       micalg = g_strdup_printf("pgp-%s", g_ascii_strdown(gpgme_hash_algo_name(
+                               result->signatures->hash_algo),-1));
+               } else {
+                       micalg = g_strdup(gpgme_hash_algo_name(
+                               result->signatures->hash_algo));
+               }
+               while (sig) {
+                       debug_print("valid signature: %s\n", sig->fpr);
+                       sig = sig->next;
+               }
+       } else if (result && result->invalid_signers) {
+               gpgme_invalid_key_t invalid = result->invalid_signers;
+               while (invalid) {
+                       g_warning("invalid signer: %s (%s)", invalid->fpr, 
+                               gpgme_strerror(invalid->reason));
+                       privacy_set_error(_("Data signing failed due to invalid signer: %s"), 
+                               gpgme_strerror(invalid->reason));
+                       invalid = invalid->next;
+               }
+               gpgme_release(ctx);
+               return FALSE;
+       } else {
+               /* can't get result (maybe no signing key?) */
+               debug_print("gpgme_op_sign_result error\n");
+               privacy_set_error(_("Data signing failed, no results."));
+               gpgme_release(ctx);
+               return FALSE;
+       }
+
+       sigcontent = sgpgme_data_release_and_get_mem(gpgsig, &len);
+       gpgme_data_release(gpgtext);
+       g_free(textstr);
+
+       if (sigcontent == NULL || len <= 0) {
+               g_warning("sgpgme_data_release_and_get_mem failed");
+               privacy_set_error(_("Data signing failed, no contents."));
+               g_free(micalg);
+               g_free(sigcontent);
+               return FALSE;
+       }
+
+       /* add signature */
+       g_hash_table_insert(sigmultipart->typeparameters, g_strdup("micalg"),
+                            micalg);
+
+       newinfo = procmime_mimeinfo_new();
+       newinfo->type = MIMETYPE_APPLICATION;
+       newinfo->subtype = g_strdup("pgp-signature");
+       newinfo->description = g_strdup(_("OpenPGP digital signature"));
+       newinfo->content = MIMECONTENT_MEM;
+       newinfo->data.mem = g_malloc(len + 1);
+       g_memmove(newinfo->data.mem, sigcontent, len);
+       newinfo->data.mem[len] = '\0';
+       g_node_append(sigmultipart->node, newinfo->node);
+
+       g_free(sigcontent);
+       gpgme_release(ctx);
+
+       return TRUE;
+}
+gchar *pgpmime_get_encrypt_data(GSList *recp_names)
+{
+       return sgpgme_get_encrypt_data(recp_names, GPGME_PROTOCOL_OpenPGP);
+}
+
+static const gchar *pgpmime_get_encrypt_warning(void)
+{
+       if (prefs_gpg_should_skip_encryption_warning(pgpmime_system.id))
+               return NULL;
+       else
+               return _("Please note that email headers, like Subject, "
+                        "are not encrypted by the PGP/Mime system.");
+}
+
+static void pgpmime_inhibit_encrypt_warning(gboolean inhibit)
+{
+       if (inhibit)
+               prefs_gpg_add_skip_encryption_warning(pgpmime_system.id);
+       else
+               prefs_gpg_remove_skip_encryption_warning(pgpmime_system.id);
+}
+
+gboolean pgpmime_encrypt(MimeInfo *mimeinfo, const gchar *encrypt_data)
+{
+       MimeInfo *msgcontent, *encmultipart, *newinfo;
+       FILE *fp;
+       gchar *boundary, *enccontent;
+       size_t len;
+       gchar *textstr;
+       gpgme_data_t gpgtext = NULL, gpgenc = NULL;
+       gpgme_ctx_t ctx = NULL;
+       gpgme_key_t *kset = NULL;
+       gchar **fprs = g_strsplit(encrypt_data, " ", -1);
+       gint i = 0;
+       gpgme_error_t err;
+       
+       while (fprs[i] && strlen(fprs[i])) {
+               i++;
+       }
+       
+       kset = g_malloc(sizeof(gpgme_key_t)*(i+1));
+       memset(kset, 0, sizeof(gpgme_key_t)*(i+1));
+       if ((err = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR) {
+               debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
+               g_free(kset);
+               return FALSE;
+       }
+       i = 0;
+       while (fprs[i] && strlen(fprs[i])) {
+               gpgme_key_t key;
+               err = gpgme_get_key(ctx, fprs[i], &key, 0);
+               if (err) {
+                       debug_print("can't add key '%s'[%d] (%s)\n", fprs[i],i, gpgme_strerror(err));
+                       privacy_set_error(_("Couldn't add GPG key %s, %s"), fprs[i], gpgme_strerror(err));
+                       g_free(kset);
+                       return FALSE;
+               }
+               debug_print("found %s at %d\n", fprs[i], i);
+               kset[i] = key;
+               i++;
+       }
+       
+       debug_print("Encrypting message content\n");
+
+       /* remove content node from message */
+       msgcontent = (MimeInfo *) mimeinfo->node->children->data;
+       g_node_unlink(msgcontent->node);
+
+       /* create temporary multipart for content */
+       encmultipart = procmime_mimeinfo_new();
+       encmultipart->type = MIMETYPE_MULTIPART;
+       encmultipart->subtype = g_strdup("encrypted");
+       boundary = generate_mime_boundary("Encrypt");
+       g_hash_table_insert(encmultipart->typeparameters, g_strdup("boundary"),
+                            g_strdup(boundary));
+       g_hash_table_insert(encmultipart->typeparameters, g_strdup("protocol"),
+                            g_strdup("application/pgp-encrypted"));
+       g_node_append(encmultipart->node, msgcontent->node);
+
+       /* write message content to temporary file */
+       fp = my_tmpfile();
+       if (fp == NULL) {
+               privacy_set_error(_("Couldn't create temporary file, %s"), strerror(errno));
+               g_free(kset);
+               return FALSE;
+       }
+       procmime_write_mimeinfo(encmultipart, fp);
+       rewind(fp);
+
+       /* read temporary file into memory */
+       textstr = get_canonical_content(fp, boundary);
+
+       fclose(fp);
+
+       /* encrypt data */
+       gpgme_data_new_from_mem(&gpgtext, textstr, (size_t)strlen(textstr), 0);
+       gpgme_data_new(&gpgenc);
+       gpgme_set_armor(ctx, 1);
+       cm_gpgme_data_rewind(gpgtext);
+       
+       err = gpgme_op_encrypt(ctx, kset, GPGME_ENCRYPT_ALWAYS_TRUST, gpgtext, gpgenc);
+
+       enccontent = sgpgme_data_release_and_get_mem(gpgenc, &len);
+       gpgme_data_release(gpgtext);
+       g_free(textstr);
+       g_free(kset);
+
+       if (enccontent == NULL || len <= 0) {
+               g_warning("sgpgme_data_release_and_get_mem failed");
+               privacy_set_error(_("Encryption failed, %s"), gpgme_strerror(err));
+               gpgme_release(ctx);
+               g_free(enccontent);
+               return FALSE;
+       }
+
+       /* create encrypted multipart */
+       g_node_unlink(msgcontent->node);
+       procmime_mimeinfo_free_all(msgcontent);
+       g_node_append(mimeinfo->node, encmultipart->node);
+
+       newinfo = procmime_mimeinfo_new();
+       newinfo->type = MIMETYPE_APPLICATION;
+       newinfo->subtype = g_strdup("pgp-encrypted");
+       newinfo->content = MIMECONTENT_MEM;
+       newinfo->data.mem = g_strdup("Version: 1\n");
+       g_node_append(encmultipart->node, newinfo->node);
+
+       newinfo = procmime_mimeinfo_new();
+       newinfo->type = MIMETYPE_APPLICATION;
+       newinfo->subtype = g_strdup("octet-stream");
+       newinfo->content = MIMECONTENT_MEM;
+       newinfo->data.mem = g_malloc(len + 1);
+       g_memmove(newinfo->data.mem, enccontent, len);
+       newinfo->data.mem[len] = '\0';
+       g_node_append(encmultipart->node, newinfo->node);
+
+       g_free(enccontent);
+       gpgme_release(ctx);
+
+       return TRUE;
+}
+
 static PrivacySystem pgpmime_system = {
        "pgpmime",                      /* id */
-       "PGP/Mime",                     /* name */
+       "PGP MIME",                     /* name */
 
        pgpmime_free_privacydata,       /* free_privacydata */
 
@@ -304,6 +761,16 @@ static PrivacySystem pgpmime_system = {
 
        pgpmime_is_encrypted,           /* is_encrypted(MimeInfo *) */
        pgpmime_decrypt,                /* decrypt(MimeInfo *) */
+
+       TRUE,
+       pgpmime_sign,
+
+       TRUE,
+       pgpmime_get_encrypt_data,
+       pgpmime_encrypt,
+       pgpmime_get_encrypt_warning,
+       pgpmime_inhibit_encrypt_warning,
+       prefs_gpg_auto_check_signatures,
 };
 
 void pgpmime_init()
@@ -316,4 +783,11 @@ void pgpmime_done()
        privacy_unregister_system(&pgpmime_system);
 }
 
+struct PluginFeature *plugin_provides(void)
+{
+       static struct PluginFeature features[] = 
+               { {PLUGIN_PRIVACY, N_("PGP/Mime")},
+                 {PLUGIN_NOTHING, NULL}};
+       return features;
+}
 #endif /* USE_GPGME */