Add support for USSD messagesreplicant-6.0

The implementation is based on the code for USSD support that was used
before the rewrite of Samsung-RIL.
USSD messages in GSM7 format are decoded to UTF8. The decoding code
was adapted from huaweigeneric-ril[1].

Signed-off-by: Wolfgang Wiedmeyer <wolfgit@wiedmeyer.de>

[1]  https://github.com/DerArtem/huaweigeneric-ril

4 files changed, 517 insertions, 0 deletions

diff --git a/Android.mk b/Android.mk
index 888d890..a7f53c6 100644
--- a/Android.mk
+++ b/Android.mk
@@ -33,6 +33,7 @@ LOCAL_SRC_FILES := \
 	network.c \
 	sound.c \
 	misc.c \
+	ss.c \
 	oem.c \
 	data.c \
 	rfs.c \
diff --git a/samsung-ril.c b/samsung-ril.c
index bcfb7ff..9f13b86 100644
--- a/samsung-ril.c
+++ b/samsung-ril.c
@@ -170,6 +170,11 @@ struct ipc_dispatch_handler ipc_fmt_dispatch_handlers[] = {
 		.command = IPC_MISC_TIME_INFO,
 		.handler = ipc_misc_time_info,
 	},
+	/* SS */
+	{
+		.command = IPC_SS_USSD,
+		.handler = ipc_ss_ussd,
+	},
 	/* OEM */
 	{
 		.command = IPC_SVC_DISPLAY_SCREEN,
@@ -440,6 +445,15 @@ struct ril_request_handler ril_request_handlers[] = {
 		.request = RIL_REQUEST_SCREEN_STATE,
 		.handler = ril_request_screen_state,
 	},
+	/* SS */
+	{
+		.request = RIL_REQUEST_SEND_USSD,
+		.handler = ril_request_send_ussd,
+	},
+	{
+		.request = RIL_REQUEST_CANCEL_USSD,
+		.handler = ril_request_cancel_ussd,
+	},
 	/* OEM */
 	{
 		.request = RIL_REQUEST_OEM_HOOK_RAW,
diff --git a/samsung-ril.h b/samsung-ril.h
index 497e72c..cf6dc15 100644
--- a/samsung-ril.h
+++ b/samsung-ril.h
@@ -366,6 +366,20 @@ int ipc_misc_time_info(struct ipc_message *message);
 int ril_request_screen_state(void *data, size_t size, RIL_Token token);
 
 /*
+ * SS
+ */
+
+enum {
+	USSD_ENCODING_UNKNOWN,
+	USSD_ENCODING_GSM7,
+	USSD_ENCODING_UCS2
+};
+
+int ipc_ss_ussd(struct ipc_message *message);
+int ril_request_send_ussd(void *data, size_t size, RIL_Token token);
+int ril_request_cancel_ussd(void *data, size_t size, RIL_Token token);
+
+/*
  * OEM
  */
 
diff --git a/ss.c b/ss.c
new file mode 100644
index 0000000..49f3152
--- /dev/null
+++ b/ss.c
@@ -0,0 +1,488 @@
+/*
+ * This file is part of Samsung-RIL.
+ *
+ * Copyright (C) 2013 Paul Kocialkowski <contact@paulk.fr>
+ * Copyright (C) 2017 Wolfgang Wiedmeyer <wolfgit@wiedmeyer.de>
+ *
+ * Samsung-RIL 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.
+ *
+ * Samsung-RIL 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 Samsung-RIL.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define LOG_TAG "RIL-SS"
+#include <utils/Log.h>
+
+#include <samsung-ril.h>
+#include <utils.h>
+
+int ipc_ss_ussd_callback(struct ipc_message *message)
+{
+	struct ipc_gen_phone_res_data *data;
+	int rc;
+
+	if (message == NULL || message->data == NULL || message->size < sizeof(struct ipc_gen_phone_res_data))
+		return -1;
+
+	data = (struct ipc_gen_phone_res_data *) message->data;
+
+	rc = ipc_gen_phone_res_check(data);
+	if (rc < 0) {
+		RIL_LOGE("There was an error, aborting USSD request");
+		goto error;
+	}
+
+	RIL_LOGD("USSD callback code 0x%04x", data->code);
+
+	// catch error codes if no IPC_SS_USSD notification is sent
+	if ((data->code & 0xff) == 0x32 || (data->code & 0xff) == 0x24)
+		goto error;
+
+	ril_request_complete(ipc_fmt_request_token(message->aseq), RIL_E_SUCCESS, NULL, 0);
+	goto complete;
+
+error:
+	ril_request_data_free(RIL_REQUEST_SEND_USSD);
+	ril_request_complete(ipc_fmt_request_token(message->aseq), RIL_E_GENERIC_FAILURE, NULL, 0);
+
+complete:
+	return 0;
+}
+
+/*
+ * Converts ASCII (7 bits) data to GSM7 (8 bits)
+ */
+int ril2ipc_ascii2gsm7(char *data, unsigned char **data_enc, int length)
+{
+	int d_off, d_pos, a_off, a_pos = 0;
+	int i;
+	int enc_length;
+	unsigned char *enc;
+
+	enc_length = ((length * 7) - (length * 7) % 8) / 8;
+	enc_length += (length * 7) % 8 > 0 ? 1 : 0;
+
+	// FIXME: why does Samsung do this?
+	enc_length++;
+
+	enc = malloc(enc_length);
+	memset(enc, 0, enc_length);
+
+	for (i = 0 ; i < length ; i++) {
+		// offset from the right of data to keep
+		d_off = i % 8;
+
+		// position of the data we keep
+		d_pos = ((i * 7) - (i * 7) % 8) / 8;
+		d_pos += (i * 7) % 8 > 0 ? 1 : 0;
+
+		// adding the data with correct offset
+		enc[d_pos] |= data[i] >> d_off;
+
+		// numbers of bits to omit to get data to add another place
+		a_off = 8 - d_off;
+		// position (on the encoded feed) of the data to add
+		a_pos = d_pos - 1;
+
+		// adding the data to add at the correct position
+		enc[a_pos] |= data[i] << a_off;
+	}
+
+	*data_enc = enc;
+
+	// FIXME: what is going on here?
+	enc[enc_length - 2] |= 0x30;
+	enc[enc_length - 1] = 0x02;
+
+	return enc_length;
+}
+
+int ril_request_send_ussd(void *data, size_t size, RIL_Token token)
+{
+	char *data_enc = NULL;
+	int data_enc_len = 0;
+	char *message = NULL;
+	struct ipc_ss_ussd_header *ussd = NULL;
+	int message_size = 0xc0;
+	void *ussd_state_data;
+	size_t ussd_state_size;
+	unsigned char ussd_state = 0;
+	struct ril_request *request;
+	int rc;
+
+	if (data == NULL || size < sizeof(char *))
+		goto error;
+
+	rc = ril_radio_state_check(RADIO_STATE_SIM_NOT_READY);
+	if (rc < 0)
+		return RIL_REQUEST_UNHANDLED;
+
+	request = ril_request_find_request_status(RIL_REQUEST_SEND_USSD, RIL_REQUEST_HANDLED);
+	if (request != NULL) {
+		return RIL_REQUEST_UNHANDLED;
+	}
+
+	ussd_state_size = ril_request_data_size_get(RIL_REQUEST_SEND_USSD);
+	ussd_state_data = ril_request_data_get(RIL_REQUEST_SEND_USSD);
+
+	if (ussd_state_data != NULL && ussd_state_size > 0) {
+		ussd_state = *((unsigned char *) ussd_state_data);
+		free(ussd_state_data);
+	}
+
+	switch (ussd_state) {
+		case 0:
+		case IPC_SS_USSD_NO_ACTION_REQUIRE:
+		case IPC_SS_USSD_TERMINATED_BY_NET:
+		case IPC_SS_USSD_OTHER_CLIENT:
+		case IPC_SS_USSD_NOT_SUPPORT:
+		case IPC_SS_USSD_TIME_OUT:
+			RIL_LOGD("USSD Tx encoding is GSM7");
+
+			data_enc_len = ril2ipc_ascii2gsm7(data, (unsigned char**)&data_enc, (int) size);
+			if (data_enc_len > message_size) {
+				RIL_LOGE("USSD message size is too long, aborting");
+				goto error;
+			}
+
+			message = malloc(message_size);
+			memset(message, 0, message_size);
+
+			ussd = (struct ipc_ss_ussd_header *) message;
+			ussd->state = IPC_SS_USSD_NO_ACTION_REQUIRE;
+			ussd->dcs = 0x0f; // GSM7 in that case
+			ussd->length = data_enc_len;
+
+			memcpy((void *) (message + sizeof(struct ipc_ss_ussd_header)), data_enc, data_enc_len);
+
+			break;
+		case IPC_SS_USSD_ACTION_REQUIRE:
+		default:
+			RIL_LOGD("USSD Tx encoding is ASCII");
+
+			data_enc_len = asprintf(&data_enc, "%s", (char*)data);
+
+			if (data_enc_len > message_size) {
+				RIL_LOGE("USSD message size is too long, aborting");
+				goto error;
+			}
+
+			message = malloc(message_size);
+			memset(message, 0, message_size);
+
+			ussd = (struct ipc_ss_ussd_header *) message;
+			ussd->state = IPC_SS_USSD_ACTION_REQUIRE;
+			ussd->dcs = 0x0f; // ASCII in that case
+			ussd->length = data_enc_len;
+
+			memcpy((void *) (message + sizeof(struct ipc_ss_ussd_header)), data_enc, data_enc_len);
+
+			break;
+	}
+
+	if (message == NULL) {
+		RIL_LOGE("USSD message is empty, aborting");
+		goto error;
+	}
+
+	ipc_gen_phone_res_expect_callback(ipc_fmt_request_seq(token), IPC_SS_USSD,
+		ipc_ss_ussd_callback);
+
+	rc = ipc_fmt_send(ipc_fmt_request_seq(token), IPC_SS_USSD, IPC_TYPE_EXEC, (void *) message, message_size);
+	if (rc < 0)
+		goto error;
+
+	rc = RIL_REQUEST_HANDLED;
+	goto complete;
+
+error:
+	ril_request_complete(token, RIL_E_GENERIC_FAILURE, NULL, 0);
+	rc = RIL_REQUEST_COMPLETED;
+
+complete:
+	if (data_enc != NULL && data_enc_len > 0)
+		free(data_enc);
+
+	return rc;
+}
+
+int ril_request_cancel_ussd(void *data, size_t size, RIL_Token token)
+{
+	struct ipc_ss_ussd_header ussd;
+	int rc;
+
+	rc = ril_radio_state_check(RADIO_STATE_SIM_NOT_READY);
+	if (rc < 0)
+		return RIL_REQUEST_UNHANDLED;
+
+	memset(&ussd, 0, sizeof(ussd));
+
+	ussd.state = IPC_SS_USSD_TERMINATED_BY_NET;
+
+	rc = ipc_gen_phone_res_expect_complete(ipc_fmt_request_seq(token), IPC_SS_USSD);
+	if (rc < 0)
+		goto error;
+
+	rc = ipc_fmt_send(ipc_fmt_request_seq(token), IPC_SS_USSD, IPC_TYPE_EXEC, (void *) &ussd, sizeof(ussd));
+	if (rc < 0)
+		goto error;
+
+	rc = RIL_REQUEST_HANDLED;
+	goto complete;
+
+error:
+	ril_request_complete(token, RIL_E_GENERIC_FAILURE, NULL, 0);
+	rc = RIL_REQUEST_COMPLETED;
+
+complete:
+	return rc;
+}
+
+int ipc2ril_ussd_state(struct ipc_ss_ussd_header *ussd, char *message[2])
+{
+	if (ussd == NULL || message == NULL)
+		return -1;
+
+	switch (ussd->state) {
+		case IPC_SS_USSD_NO_ACTION_REQUIRE:
+			asprintf(&message[0], "%d", 0);
+			break;
+		case IPC_SS_USSD_ACTION_REQUIRE:
+			asprintf(&message[0], "%d", 1);
+			break;
+		case IPC_SS_USSD_TERMINATED_BY_NET:
+			asprintf(&message[0], "%d", 2);
+			break;
+		case IPC_SS_USSD_OTHER_CLIENT:
+			asprintf(&message[0], "%d", 3);
+			break;
+		case IPC_SS_USSD_NOT_SUPPORT:
+			asprintf(&message[0], "%d", 4);
+			break;
+		case IPC_SS_USSD_TIME_OUT:
+			asprintf(&message[0], "%d", 5);
+			break;
+	}
+
+	return 0;
+}
+
+int ipc2ril_ussd_encoding(int data_encoding)
+{
+	switch (data_encoding >> 4) {
+	case 0x00:
+	case 0x02:
+	case 0x03:
+		return USSD_ENCODING_GSM7;
+	case 0x01:
+		if (data_encoding == 0x10)
+			return USSD_ENCODING_GSM7;
+		if (data_encoding == 0x11)
+			return USSD_ENCODING_UCS2;
+		break;
+	case 0x04:
+	case 0x05:
+	case 0x06:
+	case 0x07:
+		if (data_encoding & 0x20)
+			return USSD_ENCODING_UNKNOWN;
+		if (((data_encoding >> 2) & 3) == 0)
+			return USSD_ENCODING_GSM7;
+		if (((data_encoding >> 2) & 3) == 2)
+			return USSD_ENCODING_UCS2;
+		break;
+	case 0xF:
+		if (!(data_encoding & 4))
+			return USSD_ENCODING_GSM7;
+		break;
+	}
+
+	return USSD_ENCODING_UNKNOWN;
+}
+
+/* writes the utf8 character encoded in v
+ * to the buffer utf8 at the specified offset
+ */
+int ipc2ril_utf8_write(char *utf8, int offset, int v)
+{
+	int result;
+
+	if (v < 0x80) {
+		result = 1;
+		if (utf8)
+			utf8[offset] = (char)v;
+	} else if (v < 0x800) {
+		result = 2;
+		if (utf8) {
+			utf8[offset + 0] = (char)(0xc0 | (v >> 6));
+			utf8[offset + 1] = (char)(0x80 | (v & 0x3f));
+		}
+	} else if (v < 0x10000) {
+		result = 3;
+		if (utf8) {
+			utf8[offset + 0] = (char)(0xe0 | (v >> 12));
+			utf8[offset + 1] = (char)(0x80 | ((v >> 6) & 0x3f));
+			utf8[offset + 2] = (char)(0x80 | (v & 0x3f));
+		}
+	} else {
+		result = 4;
+		if (utf8) {
+			utf8[offset + 0] = (char)(0xf0 | ((v >> 18) & 0x7));
+			utf8[offset + 1] = (char)(0x80 | ((v >> 12) & 0x3f));
+			utf8[offset + 2] = (char)(0x80 | ((v >> 6) & 0x3f));
+			utf8[offset + 3] = (char)(0x80 | (v & 0x3f));
+		}
+	}
+
+	return result;
+}
+
+#define  GSM_7BITS_ESCAPE   0x1b
+
+/* For each gsm7 code value, this table gives the equivalent
+ * UTF-8 code point.
+ */
+unsigned short gsm7bits_to_unicode[128] = {
+  '@', 0xa3,  '$', 0xa5, 0xe8, 0xe9, 0xf9, 0xec, 0xf2, 0xc7, '\n', 0xd8, 0xf8, '\r', 0xc5, 0xe5,
+0x394,  '_',0x3a6,0x393,0x39b,0x3a9,0x3a0,0x3a8,0x3a3,0x398,0x39e,    0, 0xc6, 0xe6, 0xdf, 0xc9,
+  ' ',  '!',  '"',  '#', 0xa4,  '%',  '&', '\'',  '(',  ')',  '*',  '+',  ',',  '-',  '.',  '/',
+  '0',  '1',  '2',  '3',  '4',  '5',  '6',  '7',  '8',  '9',  ':',  ';',  '<',  '=',  '>',  '?',
+ 0xa1,  'A',  'B',  'C',  'D',  'E',  'F',  'G',  'H',  'I',  'J',  'K',  'L',  'M',  'N',  'O',
+  'P',  'Q',  'R',  'S',  'T',  'U',  'V',  'W',  'X',  'Y',  'Z', 0xc4, 0xd6,0x147, 0xdc, 0xa7,
+ 0xbf,  'a',  'b',  'c',  'd',  'e',  'f',  'g',  'h',  'i',  'j',  'k',  'l',  'm',  'n',  'o',
+  'p',  'q',  'r',  's',  't',  'u',  'v',  'w',  'x',  'y',  'z', 0xe4, 0xf6, 0xf1, 0xfc, 0xe0,
+};
+
+/* For each gsm7 extended code value, this table gives the equivalent
+ * UTF-8 code point.
+ */
+unsigned short gsm7bits_extend_to_unicode[128] = {
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,'\f',   0,   0,   0,   0,   0,
+    0,   0,   0,   0, '^',   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,   0,   0,   0, '{', '}',   0,   0,   0,   0,   0,'\\',
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0, '[', '~', ']',   0,
+  '|',   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,0x20ac, 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+};
+
+int ipc2ril_utf8_from_gsm7(unsigned char *data, char **utf8, int length)
+{
+	int septet_offset = 0;
+	int shift = (septet_offset & 7);
+	int septet_count = 0, escaped = 0, result = 0;
+	unsigned char *src = data;
+
+	src += (septet_offset >> 3);
+	septet_count = (length * 8) / 7; // round down
+
+	for (; septet_count > 0; septet_count--) {
+		int c = (src[0] >> shift) & 0x7f;
+		int v;
+		if (shift > 1) {
+			c = ((src[1] << (8-shift)) | c) & 0x7f;
+		}
+		if (escaped) {
+			v = gsm7bits_extend_to_unicode[c];
+		} else if (c == GSM_7BITS_ESCAPE) {
+			escaped = 1;
+			goto NextSeptet;
+		} else {
+			v = gsm7bits_to_unicode[c];
+		}
+		result += ipc2ril_utf8_write(*utf8, result, v);
+
+	NextSeptet:
+		shift += 7;
+		if (shift >= 8) {
+			shift -= 8;
+			src += 1;
+		}
+	}
+
+	return  result;
+}
+
+int ipc_ss_ussd(struct ipc_message *message)
+{
+	char *data_dec = NULL;
+	int data_dec_len = 0;
+	char *ussd_message[2];
+	int ussd_encoding;
+	struct ipc_ss_ussd_header *ussd = NULL;
+	unsigned char state;
+	int rc;
+
+	if (message == NULL || message->data == NULL || message->size < sizeof(struct ipc_ss_ussd_header))
+		goto error;
+
+	memset(ussd_message, 0, sizeof(ussd_message));
+
+	ussd = (struct ipc_ss_ussd_header *) message->data;
+
+	rc = ipc2ril_ussd_state(ussd, ussd_message);
+	if (rc < 0)
+		goto error;
+
+	ril_request_data_set_uniq(RIL_REQUEST_SEND_USSD, (void *) &ussd->state, sizeof(unsigned char));
+
+	if (ussd->length > 0 && message->size > 0 && message->data != NULL) {
+		ussd_encoding = ipc2ril_ussd_encoding(ussd->dcs);
+		switch (ussd_encoding) {
+			case USSD_ENCODING_GSM7:
+				RIL_LOGD("USSD Rx encoding is GSM7");
+
+				data_dec_len = ipc2ril_utf8_from_gsm7((unsigned char *) message->data + sizeof(struct ipc_ss_ussd_header),
+									&data_dec, message->size - sizeof(struct ipc_ss_ussd_header));
+
+				data_dec = malloc(data_dec_len+1);
+				memset(data_dec, 0, data_dec_len);
+
+				ipc2ril_utf8_from_gsm7((unsigned char *) message->data + sizeof(struct ipc_ss_ussd_header),
+							&data_dec, message->size - sizeof(struct ipc_ss_ussd_header));
+				asprintf(&ussd_message[1], "%s", data_dec);
+				ussd_message[1][data_dec_len] = '\0';
+				break;
+			case USSD_ENCODING_UCS2:
+				RIL_LOGD("USSD Rx encoding %x is UCS2", ussd->dcs);
+
+				data_dec_len = message->size - sizeof(struct ipc_ss_ussd_header);
+				ussd_message[1] = malloc(data_dec_len * 4 + 1);
+
+				int i, result = 0;
+				char *ucs2 = (char*)message->data + sizeof(struct ipc_ss_ussd_header);
+				for (i = 0; i < data_dec_len; i += 2) {
+					int c = (ucs2[i] << 8) | ucs2[1 + i];
+					result += ipc2ril_utf8_write(ussd_message[1], result, c);
+				}
+				ussd_message[1][result] = '\0';
+				break;
+			default:
+				RIL_LOGD("USSD Rx encoding %x is unknown, assuming ASCII",
+					ussd->dcs);
+
+				data_dec_len = message->size - sizeof(struct ipc_ss_ussd_header);
+				asprintf(&ussd_message[1], "%s", (unsigned char *) message->data + sizeof(struct ipc_ss_ussd_header));
+				ussd_message[1][data_dec_len] = '\0';
+				break;
+		}
+	}
+
+	ril_request_unsolicited(RIL_UNSOL_ON_USSD, ussd_message, sizeof(ussd_message));
+	goto complete;
+
+error:
+	ril_request_complete(ipc_fmt_request_token(message->aseq), RIL_E_GENERIC_FAILURE, NULL, 0);
+
+complete:
+	return 0;
+}