provision: add plugin to provision from config file

This plugin allows to provision gprs-context data based on MCC and MNC.
This is useful when provisioning using mbpi fails (either because you
are using a private APN or because there are multiple internet type context
for your operator in mbpi database).
Config file is STORAGEDIR/provisioning.
Config file should look like that:
[operator:MCC1,MNC1]
internet.AccessPointName=apn1
internet.Username=myUsername
internet.Password=myPassword
internet.AuthenticationMethod=pap
internet.Protocol=ipv6
[operator:MCC2,MNC2]
internet.AccessPointName=apn2

The only mandatory parameter for each operator is internet.AccessPointName.

Parameter description:
internet.AccessPointName: APN
internet.Username: Username
internet.Password: Password
internet.AuthenticationMethod: authentication method.
 Possible values are:
  - pap
  - chap
 Default is chap if unset.
internet.Protocol: protocol
 Possible values are:
  - ip: ipv4
  - ipv6
  - dual
 Default is ip if not set.

All parameters are prefixed with internet to be able to extend this plugin
to other type of contexts (MMS, ...).

Makefile.am

@@ -555,6 +555,10 @@ builtin_sources += plugins/provision.c
 
 builtin_modules += cdma_provision
 builtin_sources += plugins/cdma-provision.c
+
+builtin_modules += file_provision
+builtin_sources += plugins/file-provision.c
+
 endif
 
 if MAINTAINER_MODE

plugins/file-provision.c

@@ -0,0 +1,170 @@
+/*
+ *
+ *  oFono - Open Source Telephony
+ *
+ *  Copyright (C) 2017  Kerlink SA.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ *  This program 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.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <glib.h>
+
+#define OFONO_API_SUBJECT_TO_CHANGE
+#include <ofono/modem.h>
+#include <ofono/gprs-provision.h>
+#include <ofono/log.h>
+#include <ofono/plugin.h>
+
+#define CONFIG_FILE STORAGEDIR "/provisioning"
+
+static int config_file_provision_get_settings(const char *mcc,
+				const char *mnc, const char *spn,
+				struct ofono_gprs_provision_data **settings,
+				int *count)
+{
+	int result = 0;
+	GKeyFile *key_file = NULL;
+	char *setting_group = NULL;
+	char *value;
+
+	DBG("Finding settings for MCC %s, MNC %s, SPN '%s'", mcc, mnc, spn);
+
+	*count = 0;
+	*settings = NULL;
+
+	key_file = g_key_file_new();
+
+	if (!g_key_file_load_from_file(key_file, CONFIG_FILE, 0, NULL)) {
+		result = -ENOENT;
+		goto error;
+	}
+
+	setting_group = g_try_malloc(strlen("operator:") + strlen(mcc) +
+							strlen(mnc) + 2);
+	if (setting_group == NULL) {
+		result = -ENOMEM;
+		goto error;
+	}
+
+	sprintf(setting_group, "operator:%s,%s", mcc, mnc);
+
+	value = g_key_file_get_string(key_file, setting_group,
+					"internet.AccessPointName", NULL);
+
+	if (value == NULL)
+		goto error;
+
+	*settings = g_try_new0(struct ofono_gprs_provision_data, 1);
+	if (*settings == NULL) {
+		result = -ENOMEM;
+		goto error;
+	}
+
+	*count = 1;
+
+	(*settings)[0].type = OFONO_GPRS_CONTEXT_TYPE_INTERNET;
+	(*settings)[0].apn = value;
+
+	value = g_key_file_get_string(key_file, setting_group,
+					"internet.Username", NULL);
+
+	if (value != NULL)
+		(*settings)[0].username = value;
+
+	value = g_key_file_get_string(key_file, setting_group,
+					"internet.Password", NULL);
+
+	if (value != NULL)
+		(*settings)[0].password = value;
+
+	(*settings)[0].auth_method = OFONO_GPRS_AUTH_METHOD_CHAP;
+	value = g_key_file_get_string(key_file, setting_group,
+					"internet.AuthenticationMethod", NULL);
+
+	if (value != NULL) {
+		if (g_strcmp0(value, "chap") == 0)
+			(*settings)[0].auth_method =
+						OFONO_GPRS_AUTH_METHOD_CHAP;
+		else if (g_strcmp0(value, "pap") == 0)
+			(*settings)[0].auth_method =
+						OFONO_GPRS_AUTH_METHOD_PAP;
+		else
+			DBG("Unknown auth method: %s", value);
+
+		g_free(value);
+	}
+
+	(*settings)[0].proto = OFONO_GPRS_PROTO_IP;
+	value = g_key_file_get_string(key_file, setting_group,
+					"internet.Protocol", NULL);
+
+	if (value != NULL) {
+		DBG("CRO value:%s", value);
+		if (g_strcmp0(value, "ip") == 0) {
+			DBG("CRO value=ip");
+			(*settings)[0].proto = OFONO_GPRS_PROTO_IP;
+		} else if (g_strcmp0(value, "ipv6") == 0) {
+			DBG("CRO value=ipv6");
+			(*settings)[0].proto = OFONO_GPRS_PROTO_IPV6;
+		} else if (g_strcmp0(value, "dual") == 0)
+			(*settings)[0].proto = OFONO_GPRS_PROTO_IPV4V6;
+		else
+			DBG("Unknown protocol: %s", value);
+
+		g_free(value);
+	}
+
+error:
+	if (key_file != NULL)
+		g_key_file_free(key_file);
+
+	if (setting_group != NULL)
+		g_free(setting_group);
+
+	if (result == 0 && *count > 0)
+		DBG("Found. APN:%s, proto:%d, auth_method:%d",
+				(*settings)[0].apn, (*settings)[0].proto,
+				(*settings)[0].auth_method);
+	else
+		DBG("Not found. Result:%d", result);
+
+	return result;
+}
+
+static struct ofono_gprs_provision_driver config_file_provision_driver = {
+	.name		= "GPRS context provisioning",
+	.get_settings	= config_file_provision_get_settings,
+};
+
+static int config_file_provision_init(void)
+{
+	return ofono_gprs_provision_driver_register(
+						&config_file_provision_driver);
+}
+
+static void config_file_provision_exit(void)
+{
+	ofono_gprs_provision_driver_unregister(
+						&config_file_provision_driver);
+}
+
+OFONO_PLUGIN_DEFINE(file_provision, "Gprs Provisioning Plugin",
+			VERSION, OFONO_PLUGIN_PRIORITY_HIGH,
+			config_file_provision_init,
+			config_file_provision_exit)