Subject: [PATCH] implement POP3 CRAM-MD5 AUTH

diff --git a/libsylph/pop.c b/libsylph/pop.c
index 8cb7f5c..5b840a6 100644
--- a/libsylph/pop.c
+++ b/libsylph/pop.c
@@ -35,6 +35,8 @@
 
 #include "pop.h"
 #include "md5.h"
+#include "md5_hmac.h"
+#include "base64.h"
 #include "prefs.h"
 #include "prefs_account.h"
 #include "utils.h"
@@ -45,6 +47,8 @@ gint pop3_greeting_recv		(Pop3Session *session,
 gint pop3_getauth_user_send	(Pop3Session *session);
 gint pop3_getauth_pass_send	(Pop3Session *session);
 gint pop3_getauth_apop_send	(Pop3Session *session);
+gint pop3_getauth_crammd5_send	(Pop3Session *session);
+gint pop3_getauth_crammd5_digest_send(Pop3Session *session);
 #if USE_SSL
 gint pop3_stls_send		(Pop3Session *session);
 gint pop3_stls_recv		(Pop3Session *session);
@@ -140,6 +144,45 @@ gint pop3_getauth_pass_send(Pop3Session *session)
 	return PS_SUCCESS;
 }
 
+gint pop3_getauth_crammd5_send(Pop3Session *session)
+{
+	g_return_val_if_fail(session->user != NULL, -1);
+	g_return_val_if_fail(session->pass != NULL, -1);
+
+	session->state = POP3_GETAUTH_CRAM_MD5;
+	pop3_gen_send(session, "AUTH CRAM-MD5");
+	return PS_SUCCESS;
+}
+
+gint pop3_getauth_crammd5_digest_send(Pop3Session *session)
+{
+	gchar hexdigest[33];
+	gchar *response;
+	gchar *response64;
+
+	g_return_val_if_fail(session->user != NULL, -1);
+	g_return_val_if_fail(session->pass != NULL, -1);
+	g_return_val_if_fail(session->digest != NULL, -1);
+
+	md5_hex_hmac(hexdigest, (guchar *)session->digest, session->digest_len,
+                     (guchar *)session->pass, strlen(session->pass));
+
+	response = g_strdup_printf("%s %s", session->user, hexdigest);
+	log_print("POP3> [Encoded: %s]\n", response);
+	response64 = g_malloc((strlen(response) + 3) * 2 + 1);
+	base64_encode(response64, (guchar *)response, strlen(response));
+
+	pop3_gen_send(session, response64);
+	session->state = POP3_GETAUTH_CRAM_MD5_DIGEST;
+
+	g_free(response);
+	g_free(response64);
+	g_free(session->digest);
+	session->digest = NULL;
+
+	return PS_SUCCESS;
+}
+
 gint pop3_getauth_apop_send(Pop3Session *session)
 {
 	gchar *start, *end;
@@ -193,6 +236,23 @@ gint pop3_getrange_stat_send(Pop3Session *session)
 	return PS_SUCCESS;
 }
 
+gint pop3_digest_crammd5_recv(Pop3Session *session, const gchar *msg)
+{
+	if (msg) log_print("POP3< %s\n", msg);
+
+	if(!msg || msg[0] != '+' || msg[1] != ' ') {
+		return PS_ERROR;
+	}
+
+	session->digest = g_malloc(strlen(msg + 2) + 1);
+	session->digest_len = base64_decode((guchar *)session->digest, msg + 2, -1);
+	session->digest[session->digest_len] = 0;
+
+	log_print("POP3< [Decoded: %s]\n", session->digest);
+
+	return PS_SUCCESS;
+}
+
 gint pop3_getrange_stat_recv(Pop3Session *session, const gchar *msg)
 {
 	if (sscanf(msg, "%d %lld", &session->count, &session->total_bytes) != 2) {
@@ -703,6 +763,8 @@ Pop3ErrorValue pop3_ok(Pop3Session *session, const gchar *msg)
 			case POP3_GETAUTH_USER:
 			case POP3_GETAUTH_PASS:
 			case POP3_GETAUTH_APOP:
+			case POP3_GETAUTH_CRAM_MD5:
+			case POP3_GETAUTH_CRAM_MD5_DIGEST:
 				log_warning(_("error occurred on authentication\n"));
 				ok = PS_AUTHFAIL;
 				break;
@@ -738,6 +800,7 @@ static gint pop3_session_recv_msg(Session *session, const gchar *msg)
 
 	body = msg;
 	if (pop3_session->state != POP3_GETRANGE_UIDL_RECV &&
+	    pop3_session->state != POP3_GETAUTH_CRAM_MD5 &&
 	    pop3_session->state != POP3_GETSIZE_LIST_RECV) {
 		val = pop3_ok(pop3_session, msg);
 		if (val != PS_SUCCESS) {
@@ -772,19 +835,33 @@ static gint pop3_session_recv_msg(Session *session, const gchar *msg)
 			val = pop3_stls_send(pop3_session);
 		else
 #endif
-		if (pop3_session->ac_prefs->use_apop_auth)
+		switch(pop3_session->ac_prefs->pop_auth_type) {
+		case POP3_AUTH_APOP:
 			val = pop3_getauth_apop_send(pop3_session);
-		else
+			break;
+		case POP3_AUTH_LOGIN:
 			val = pop3_getauth_user_send(pop3_session);
+			break;
+		case POP3_AUTH_CRAM_MD5:
+			val = pop3_getauth_crammd5_send(pop3_session);
+			break;
+		}
 		break;
 #if USE_SSL
 	case POP3_STLS:
 		if ((val = pop3_stls_recv(pop3_session)) != PS_SUCCESS)
 			return -1;
-		if (pop3_session->ac_prefs->use_apop_auth)
+		switch(pop3_session->ac_prefs->pop_auth_type) {
+		case POP3_AUTH_APOP:
 			val = pop3_getauth_apop_send(pop3_session);
-		else
+			break;
+		case POP3_AUTH_LOGIN:
 			val = pop3_getauth_user_send(pop3_session);
+			break;
+		case POP3_AUTH_CRAM_MD5:
+			val = pop3_getauth_crammd5_send(pop3_session);
+			break;
+		}
 		break;
 #endif
 	case POP3_GETAUTH_USER:
@@ -792,11 +869,18 @@ static gint pop3_session_recv_msg(Session *session, const gchar *msg)
 		break;
 	case POP3_GETAUTH_PASS:
 	case POP3_GETAUTH_APOP:
+	case POP3_GETAUTH_CRAM_MD5_DIGEST:
 		if (pop3_session->auth_only)
 			val = pop3_logout_send(pop3_session);
 		else
 			val = pop3_getrange_stat_send(pop3_session);
 		break;
+	case POP3_GETAUTH_CRAM_MD5:
+		if ((val = pop3_digest_crammd5_recv(pop3_session, body)) != PS_SUCCESS)
+			return -1;
+		else
+			val = pop3_getauth_crammd5_digest_send(pop3_session);
+		break;
 	case POP3_GETRANGE_STAT:
 		if ((val = pop3_getrange_stat_recv(pop3_session, body)) != PS_SUCCESS)
 			return -1;
diff --git a/libsylph/pop.h b/libsylph/pop.h
index 050caf5..f8c94a2 100644
--- a/libsylph/pop.h
+++ b/libsylph/pop.h
@@ -36,6 +36,12 @@ typedef struct _Pop3Session	Pop3Session;
 
 #define POP3_SESSION(obj)	((Pop3Session *)obj)
 
+typedef enum {
+	POP3_AUTH_LOGIN		= 1 << 0, /* default unencrypted user/pass auth */
+	POP3_AUTH_APOP		= 1 << 1, /* APop method */
+	POP3_AUTH_CRAM_MD5      = 1 << 2, /* cram-md5 digest */
+} Pop3AuthType;
+
 typedef enum {
 	POP3_READY,
 	POP3_GREETING,
@@ -43,6 +49,8 @@ typedef enum {
 	POP3_GETAUTH_USER,
 	POP3_GETAUTH_PASS,
 	POP3_GETAUTH_APOP,
+	POP3_GETAUTH_CRAM_MD5,
+	POP3_GETAUTH_CRAM_MD5_DIGEST,
 	POP3_GETRANGE_STAT,
 	POP3_GETRANGE_LAST,
 	POP3_GETRANGE_UIDL,
@@ -114,8 +122,10 @@ struct _Pop3Session
 	PrefsAccount *ac_prefs;
 
 	gchar *greeting;
+	gchar *digest;
 	gchar *user;
 	gchar *pass;
+	gint digest_len;
 	gint count;
 	gint64 total_bytes;
 	gint cur_msg;
diff --git a/libsylph/prefs_account.c b/libsylph/prefs_account.c
index 1aecba9..2a35af9 100644
--- a/libsylph/prefs_account.c
+++ b/libsylph/prefs_account.c
@@ -34,6 +34,7 @@
 #include "customheader.h"
 #include "account.h"
 #include "utils.h"
+#include "pop.h"
 
 static PrefsAccount tmp_ac_prefs;
 
@@ -54,7 +55,7 @@ static PrefParam param[] = {
 	{"inbox", "inbox", &tmp_ac_prefs.inbox, P_STRING},
 
 	/* Receive */
-	{"use_apop_auth", "FALSE", &tmp_ac_prefs.use_apop_auth, P_BOOL},
+	{"pop_auth_method", "0", &tmp_ac_prefs.pop_auth_type, P_ENUM},
 	{"remove_mail", "TRUE", &tmp_ac_prefs.rmmail, P_BOOL},
 	{"message_leave_time", "7", &tmp_ac_prefs.msg_leave_time, P_INT},
 	{"get_all_mail", "FALSE", &tmp_ac_prefs.getall, P_BOOL},
@@ -226,7 +227,7 @@ void prefs_account_read_config(PrefsAccount *ac_prefs, const gchar *label)
 	if (ac_prefs->protocol == A_APOP) {
 		debug_print("converting protocol A_APOP to new prefs.\n");
 		ac_prefs->protocol = A_POP3;
-		ac_prefs->use_apop_auth = TRUE;
+		ac_prefs->pop_auth_type = POP3_AUTH_APOP;
 	}
 
 	custom_header_read_config(ac_prefs);
diff --git a/libsylph/prefs_account.h b/libsylph/prefs_account.h
index ad899f8..249711b 100644
--- a/libsylph/prefs_account.h
+++ b/libsylph/prefs_account.h
@@ -82,7 +82,7 @@ struct _PrefsAccount
 	gchar *tmp_pass;
 
 	/* Receive */
-	gboolean use_apop_auth;
+	gint pop_auth_type;
 	gboolean rmmail;
 	gint msg_leave_time;
 	gboolean getall;
diff --git a/src/prefs_account_dialog.c b/src/prefs_account_dialog.c
index e9cba13..5d8b638 100644
--- a/src/prefs_account_dialog.c
+++ b/src/prefs_account_dialog.c
@@ -52,6 +52,7 @@
 #include "alertpanel.h"
 #include "smtp.h"
 #include "imap.h"
+#include "pop.h"
 #include "plugin.h"
 
 static gboolean cancelled;
@@ -84,7 +85,7 @@ static struct Basic {
 
 static struct Receive {
 	GtkWidget *pop3_frame;
-	GtkWidget *use_apop_chkbtn;
+	GtkWidget *pop_auth_type_optmenu;
 	GtkWidget *rmmail_chkbtn;
 	GtkWidget *leave_time_entry;
 	GtkWidget *getall_chkbtn;
@@ -227,9 +228,14 @@ static void prefs_account_protocol_set_data_from_optmenu(PrefParam *pparam);
 static void prefs_account_protocol_set_optmenu		(PrefParam *pparam);
 static void prefs_account_protocol_activated		(GtkMenuItem *menuitem);
 
+static void prefs_account_pop_auth_type_set_data_from_optmenu
+							(PrefParam *pparam);
+static void prefs_account_pop_auth_type_set_optmenu	(PrefParam *pparam);
+
 static void prefs_account_imap_auth_type_set_data_from_optmenu
 							(PrefParam *pparam);
 static void prefs_account_imap_auth_type_set_optmenu	(PrefParam *pparam);
+
 static void prefs_account_smtp_auth_type_set_data_from_optmenu
 							(PrefParam *pparam);
 static void prefs_account_smtp_auth_type_set_optmenu	(PrefParam *pparam);
@@ -270,8 +276,9 @@ static PrefsUIData ui_data[] = {
 	 prefs_set_data_from_entry, prefs_set_entry},
 
 	/* Receive */
-	{"use_apop_auth", &receive.use_apop_chkbtn,
-	 prefs_set_data_from_toggle, prefs_set_toggle},
+	{"pop_auth_method", &receive.pop_auth_type_optmenu,
+	 prefs_account_pop_auth_type_set_data_from_optmenu,
+	 prefs_account_pop_auth_type_set_optmenu},
 	{"remove_mail", &receive.rmmail_chkbtn,
 	 prefs_set_data_from_toggle, prefs_set_toggle},
 	{"message_leave_time", &receive.leave_time_entry,
@@ -893,7 +900,7 @@ static void prefs_account_receive_create(void)
 	GtkWidget *vbox1;
 	GtkWidget *frame1;
 	GtkWidget *vbox2;
-	GtkWidget *use_apop_chkbtn;
+	GtkWidget *pop_auth_type_optmenu;
 	GtkWidget *rmmail_chkbtn;
 	GtkWidget *hbox_spc;
 	GtkWidget *leave_time_label;
@@ -910,6 +917,7 @@ static void prefs_account_receive_create(void)
 	GtkWidget *inbox_btn;
 
 	GtkWidget *imap_frame;
+	GtkWidget *optmenu_pop;
 	GtkWidget *optmenu;
 	GtkWidget *optmenu_menu;
 	GtkWidget *menuitem;
@@ -936,8 +944,26 @@ static void prefs_account_receive_create(void)
 	gtk_container_add (GTK_CONTAINER (frame1), vbox2);
 	gtk_container_set_border_width (GTK_CONTAINER (vbox2), 8);
 
-	PACK_CHECK_BUTTON (vbox2, use_apop_chkbtn,
-			   _("Use secure authentication (APOP)"));
+	hbox1 = gtk_hbox_new (FALSE, 8);
+	gtk_widget_show (hbox1);
+	gtk_box_pack_start (GTK_BOX (vbox2), hbox1, FALSE, FALSE, 0);
+
+	label = gtk_label_new (_("Authentication method"));
+	gtk_widget_show (label);
+	gtk_box_pack_start (GTK_BOX (hbox1), label, FALSE, FALSE, 0);
+
+	optmenu = gtk_option_menu_new ();
+	gtk_widget_show (optmenu);
+	gtk_box_pack_start (GTK_BOX (hbox1), optmenu, FALSE, FALSE, 0);
+
+	optmenu_menu = gtk_menu_new ();
+
+	MENUITEM_ADD (optmenu_menu, menuitem, _("Unencrypted (standard)"), POP3_AUTH_LOGIN);
+	MENUITEM_ADD (optmenu_menu, menuitem, _("Use secure authentication (APOP)"), POP3_AUTH_APOP);
+	MENUITEM_ADD (optmenu_menu, menuitem, "CRAM-MD5", POP3_AUTH_CRAM_MD5);
+
+	gtk_option_menu_set_menu (GTK_OPTION_MENU (optmenu), optmenu_menu);
+	optmenu_pop = optmenu;
 
 	PACK_CHECK_BUTTON (vbox2, rmmail_chkbtn,
 			   _("Remove messages on server when received"));
@@ -1106,7 +1132,7 @@ static void prefs_account_receive_create(void)
 		 _("`Get all' checks for new messages on this account"));
 
 	receive.pop3_frame            = frame1;
-	receive.use_apop_chkbtn       = use_apop_chkbtn;
+	receive.pop_auth_type_optmenu = optmenu_pop;
 	receive.rmmail_chkbtn         = rmmail_chkbtn;
 	receive.leave_time_entry      = leave_time_entry;
 	receive.getall_chkbtn         = getall_chkbtn;
@@ -2447,7 +2473,7 @@ static void prefs_account_protocol_set_optmenu(PrefParam *pparam)
 	gtk_menu_item_activate(GTK_MENU_ITEM(menuitem));
 }
 
-static void prefs_account_imap_auth_type_set_data_from_optmenu(PrefParam *pparam)
+static void prefs_account_auth_type_set_data_from_optmenu(PrefParam *pparam)
 {
 	PrefsUIData *ui_data;
 	GtkWidget *menu;
@@ -2463,10 +2489,21 @@ static void prefs_account_imap_auth_type_set_data_from_optmenu(PrefParam *pparam
 		(g_object_get_data(G_OBJECT(menuitem), MENU_VAL_ID));
 }
 
-static void prefs_account_imap_auth_type_set_optmenu(PrefParam *pparam)
+static void prefs_account_imap_auth_type_set_data_from_optmenu(PrefParam *pparam)
+{
+	prefs_account_auth_type_set_data_from_optmenu(pparam);
+}
+
+static void prefs_account_pop_auth_type_set_data_from_optmenu(PrefParam *pparam)
+{
+	prefs_account_auth_type_set_data_from_optmenu(pparam);
+}
+
+static void prefs_account_auth_type_set_optmenu(PrefParam *pparam, gboolean is_imap)
 {
 	PrefsUIData *ui_data;
-	IMAPAuthType type = *((IMAPAuthType *)pparam->data);
+	IMAPAuthType itype;
+	Pop3AuthType ptype;
 	GtkOptionMenu *optmenu;
 	GtkWidget *menu;
 	GtkWidget *menuitem;
@@ -2477,19 +2514,38 @@ static void prefs_account_imap_auth_type_set_optmenu(PrefParam *pparam)
 
 	optmenu = GTK_OPTION_MENU(*ui_data->widget);
 
-	switch (type) {
-	case IMAP_AUTH_LOGIN:
-		gtk_option_menu_set_history(optmenu, 1);
-		break;
-	case IMAP_AUTH_PLAIN:
-		gtk_option_menu_set_history(optmenu, 2);
-		break;
-	case IMAP_AUTH_CRAM_MD5:
-		gtk_option_menu_set_history(optmenu, 3);
-		break;
-	case 0:
-	default:
-		gtk_option_menu_set_history(optmenu, 0);
+	if (is_imap) {
+		itype = *((IMAPAuthType *)pparam->data);
+		switch (itype) {
+		case IMAP_AUTH_LOGIN:
+			gtk_option_menu_set_history(optmenu, 1);
+			break;
+		case IMAP_AUTH_PLAIN:
+			gtk_option_menu_set_history(optmenu, 2);
+			break;
+		case IMAP_AUTH_CRAM_MD5:
+			gtk_option_menu_set_history(optmenu, 3);
+			break;
+		case 0:
+		default:
+			gtk_option_menu_set_history(optmenu, 0);
+		}
+	} else {
+		ptype = *((Pop3AuthType *)pparam->data);
+		switch (ptype) {
+		case POP3_AUTH_LOGIN:
+			gtk_option_menu_set_history(optmenu, 0);
+			break;
+		case POP3_AUTH_APOP:
+			gtk_option_menu_set_history(optmenu, 1);
+			break;
+		case POP3_AUTH_CRAM_MD5:
+			gtk_option_menu_set_history(optmenu, 2);
+			break;
+		case 0:
+		default:
+			gtk_option_menu_set_history(optmenu, 0);
+		}
 	}
 
 	menu = gtk_option_menu_get_menu(optmenu);
@@ -2497,6 +2553,16 @@ static void prefs_account_imap_auth_type_set_optmenu(PrefParam *pparam)
 	gtk_menu_item_activate(GTK_MENU_ITEM(menuitem));
 }
 
+static void prefs_account_imap_auth_type_set_optmenu(PrefParam *pparam)
+{
+	prefs_account_auth_type_set_optmenu(pparam, TRUE);
+}
+
+static void prefs_account_pop_auth_type_set_optmenu(PrefParam *pparam)
+{
+	prefs_account_auth_type_set_optmenu(pparam, FALSE);
+}
+
 static void prefs_account_smtp_auth_type_set_data_from_optmenu(PrefParam *pparam)
 {
 	PrefsUIData *ui_data;
diff --git a/src/rpop3.c b/src/rpop3.c
index 571671f..3f59aa0 100644
--- a/src/rpop3.c
+++ b/src/rpop3.c
@@ -884,7 +884,8 @@ static gint rpop3_session_recv_msg(Session *session, const gchar *msg)
 			val = pop3_stls_send(pop3_session);
 		else
 #endif
-		if (pop3_session->ac_prefs->use_apop_auth)
+		/* XXX FIXME: need switch block to deal with POP3_AUTH_CRAM_MD5 just like in libsylph/pop.c */
+		if (pop3_session->ac_prefs->pop_auth_type == POP3_AUTH_APOP)
 			val = pop3_getauth_apop_send(pop3_session);
 		else
 			val = pop3_getauth_user_send(pop3_session);
@@ -893,7 +894,8 @@ static gint rpop3_session_recv_msg(Session *session, const gchar *msg)
 	case POP3_STLS:
 		if ((val = pop3_stls_recv(pop3_session)) != PS_SUCCESS)
 			break;
-		if (pop3_session->ac_prefs->use_apop_auth)
+		/* XXX FIXME: need switch block to deal with POP3_AUTH_CRAM_MD5 just like in libsylph/pop.c */
+		if (pop3_session->ac_prefs->pop_auth_type == POP3_AUTH_APOP)
 			val = pop3_getauth_apop_send(pop3_session);
 		else
 			val = pop3_getauth_user_send(pop3_session);
-- 
2.20.1