import gsm48_mi_to_string() from OpenBSC

2 files changed, 47 insertions, 0 deletions

diff --git a/include/osmocore/gsm48.h b/include/osmocore/gsm48.h
index 1e963573..b752ee00 100644
--- a/include/osmocore/gsm48.h
+++ b/include/osmocore/gsm48.h
@@ -14,4 +14,8 @@ void gsm48_generate_lai(struct gsm48_loc_area_id *lai48, uint16_t mcc,
 int gsm48_generate_mid_from_tmsi(uint8_t *buf, uint32_t tmsi);
 int gsm48_generate_mid_from_imsi(uint8_t *buf, const char *imsi);
 
+/* Convert Mobile Identity (10.5.1.4) to string */
+int gsm48_mi_to_string(char *string, const int str_len,
+			const u_int8_t *mi, const int mi_len);
+
 #endif
diff --git a/src/gsm48.c b/src/gsm48.c
index 5761c67b..d024109b 100644
--- a/src/gsm48.c
+++ b/src/gsm48.c
@@ -261,3 +261,46 @@ int gsm48_generate_mid_from_imsi(uint8_t *buf, const char *imsi)
 
 	return 2 + buf[1];
 }
+
+/* Convert Mobile Identity (10.5.1.4) to string */
+int gsm48_mi_to_string(char *string, const int str_len, const u_int8_t *mi, const int mi_len)
+{
+	int i;
+	u_int8_t mi_type;
+	char *str_cur = string;
+	u_int32_t tmsi;
+
+	mi_type = mi[0] & GSM_MI_TYPE_MASK;
+
+	switch (mi_type) {
+	case GSM_MI_TYPE_NONE:
+		break;
+	case GSM_MI_TYPE_TMSI:
+		/* Table 10.5.4.3, reverse generate_mid_from_tmsi */
+		if (mi_len == GSM48_TMSI_LEN && mi[0] == (0xf0 | GSM_MI_TYPE_TMSI)) {
+			memcpy(&tmsi, &mi[1], 4);
+			tmsi = ntohl(tmsi);
+			return snprintf(string, str_len, "%u", tmsi);
+		}
+		break;
+	case GSM_MI_TYPE_IMSI:
+	case GSM_MI_TYPE_IMEI:
+	case GSM_MI_TYPE_IMEISV:
+		*str_cur++ = bcd2char(mi[0] >> 4);
+
+                for (i = 1; i < mi_len; i++) {
+			if (str_cur + 2 >= string + str_len)
+				return str_cur - string;
+			*str_cur++ = bcd2char(mi[i] & 0xf);
+			/* skip last nibble in last input byte when GSM_EVEN */
+			if( (i != mi_len-1) || (mi[0] & GSM_MI_ODD))
+				*str_cur++ = bcd2char(mi[i] >> 4);
+		}
+		break;
+	default:
+		break;
+	}
+	*str_cur++ = '\0';
+
+	return str_cur - string;
+}