gprs: Create a gprs_utils file and move to be shared code in there

We intend to move some of these routines to libosmocore but to avoid
a feature symbol clash we are prefixing these routines with gprs_.

Done with Jacob

4 files changed, 164 insertions, 134 deletions

diff --git a/openbsc/src/gprs/Makefile.am b/openbsc/src/gprs/Makefile.am
index 87dbc3059..2e26b8ae7 100644
--- a/openbsc/src/gprs/Makefile.am
+++ b/openbsc/src/gprs/Makefile.am
@@ -14,7 +14,7 @@ bin_PROGRAMS = osmo-gbproxy
 endif
 
 osmo_gbproxy_SOURCES =  gb_proxy.c gb_proxy_main.c gb_proxy_vty.c \
-			gprs_llc_parse.c crc24.c
+			gprs_llc_parse.c crc24.c gprs_utils.c
 osmo_gbproxy_LDADD = 	$(top_builddir)/src/libcommon/libcommon.a \
 			$(OSMO_LIBS)
 
diff --git a/openbsc/src/gprs/gb_proxy.c b/openbsc/src/gprs/gb_proxy.c
index f72586f19..4fa77acac 100644
--- a/openbsc/src/gprs/gb_proxy.c
+++ b/openbsc/src/gprs/gb_proxy.c
@@ -47,6 +47,7 @@
 #include <openbsc/gprs_llc.h>
 #include <openbsc/gsm_04_08.h>
 #include <openbsc/gsm_04_08_gprs.h>
+#include <openbsc/gprs_utils.h>
 
 enum gbprox_global_ctr {
 	GBPROX_GLOB_CTR_INV_BVCI,
@@ -229,47 +230,6 @@ static void peer_free(struct gbproxy_peer *peer)
 	talloc_free(peer);
 }
 
-/* FIXME: this needs to go to libosmocore/msgb.c */
-static struct msgb *msgb_copy(const struct msgb *msg, const char *name)
-{
-	struct libgb_msgb_cb *old_cb, *new_cb;
-	struct msgb *new_msg;
-
-	new_msg = msgb_alloc(msg->data_len, name);
-	if (!new_msg)
-		return NULL;
-
-	/* copy data */
-	memcpy(new_msg->_data, msg->_data, new_msg->data_len);
-
-	/* copy header */
-	new_msg->len = msg->len;
-	new_msg->data += msg->data - msg->_data;
-	new_msg->head += msg->head - msg->_data;
-	new_msg->tail += msg->tail - msg->_data;
-
-	new_msg->l1h = new_msg->_data + (msg->l1h - msg->_data);
-	new_msg->l2h = new_msg->_data + (msg->l2h - msg->_data);
-	new_msg->l3h = new_msg->_data + (msg->l3h - msg->_data);
-	new_msg->l4h = new_msg->_data + (msg->l4h - msg->_data);
-
-	/* copy GB specific data */
-	old_cb = LIBGB_MSGB_CB(msg);
-	new_cb = LIBGB_MSGB_CB(new_msg);
-
-	new_cb->bssgph = new_msg->_data + (old_cb->bssgph - msg->_data);
-	new_cb->llch = new_msg->_data + (old_cb->llch - msg->_data);
-
-	/* bssgp_cell_id is a pointer into the old msgb, so we need to make
-	 * it a pointer into the new msgb */
-	new_cb->bssgp_cell_id = new_msg->_data + (old_cb->bssgp_cell_id - msg->_data);
-	new_cb->nsei = old_cb->nsei;
-	new_cb->bvci = old_cb->bvci;
-	new_cb->tlli = old_cb->tlli;
-
-	return new_msg;
-}
-
 /* strip off the NS header */
 static void strip_ns_hdr(struct msgb *msg)
 {
@@ -277,89 +237,6 @@ static void strip_ns_hdr(struct msgb *msg)
 	msgb_pull(msg, strip_len);
 }
 
-/* TODO: Move this to libosmocore/msgb.c */
-static int msgb_resize_area(struct msgb *msg, uint8_t *area,
-			    size_t old_size, size_t new_size)
-{
-	int rc;
-	uint8_t *rest = area + old_size;
-	int rest_len = msg->len - old_size - (area - msg->data);
-	int delta_size = (int)new_size - (int)old_size;
-
-	if (delta_size == 0)
-		return 0;
-
-	if (delta_size > 0) {
-		rc = msgb_trim(msg, msg->len + delta_size);
-		if (rc < 0)
-			return rc;
-	}
-
-	memmove(area + new_size, area + old_size, rest_len);
-
-	if (msg->l1h >= rest)
-		msg->l1h += delta_size;
-	if (msg->l2h >= rest)
-		msg->l2h += delta_size;
-	if (msg->l3h >= rest)
-		msg->l3h += delta_size;
-	if (msg->l4h >= rest)
-		msg->l4h += delta_size;
-
-	if (delta_size < 0)
-		msgb_trim(msg, msg->len + delta_size);
-
-	return 0;
-}
-
-/* TODO: Move these conversion functions to a utils file. */
-char * gbprox_apn_to_str(char *out_str, const uint8_t *apn_enc, size_t rest_chars)
-{
-	char *str = out_str;
-
-	while (rest_chars > 0 && apn_enc[0]) {
-		size_t label_size = apn_enc[0];
-		if (label_size + 1 > rest_chars)
-			return NULL;
-
-		memmove(str, apn_enc + 1, label_size);
-		str += label_size;
-		rest_chars -= label_size + 1;
-		apn_enc += label_size + 1;
-
-		if (rest_chars)
-			*(str++) = '.';
-	}
-	str[0] = '\0';
-
-	return out_str;
-}
-
-int gbprox_str_to_apn(uint8_t *apn_enc, const char *str, size_t max_chars)
-{
-	uint8_t *last_len_field = apn_enc;
-	int len = 1;
-	apn_enc += 1;
-
-	while (str[0]) {
-		if (str[0] == '.') {
-			*last_len_field = (apn_enc - last_len_field) - 1;
-			last_len_field = apn_enc;
-		} else {
-			*apn_enc = str[0];
-		}
-		apn_enc += 1;
-		str += 1;
-		len += 1;
-		if (len > max_chars)
-			return -1;
-	}
-
-	*last_len_field = (apn_enc - last_len_field) - 1;
-
-	return len;
-}
-
 /* TODO: Move shift functions to libosmocore */
 
 int v_fixed_shift(uint8_t **data, size_t *data_len,
@@ -888,10 +765,10 @@ static void gbprox_patch_apn_ie(struct msgb *msg,
 		LOGP(DGPRS, LOGL_DEBUG,
 		     "Patching %s to SGSN: Removing APN '%s'\n",
 		     log_text,
-		     gbprox_apn_to_str(str1, apn, apn_len));
+		     gprs_apn_to_str(str1, apn, apn_len));
 
 		*new_apn_ie_len = 0;
-		msgb_resize_area(msg, apn_ie, apn_ie_len, 0);
+		gprs_msgb_resize_area(msg, apn_ie, apn_ie_len, 0);
 	} else {
 		/* Resize the IE */
 		char str1[110];
@@ -903,12 +780,12 @@ static void gbprox_patch_apn_ie(struct msgb *msg,
 		     "Patching %s to SGSN: "
 		     "Replacing APN '%s' -> '%s'\n",
 		     log_text,
-		     gbprox_apn_to_str(str1, apn, apn_len),
-		     gbprox_apn_to_str(str2, gbcfg.core_apn,
+		     gprs_apn_to_str(str1, apn, apn_len),
+		     gprs_apn_to_str(str2, gbcfg.core_apn,
 				       gbcfg.core_apn_size));
 
 		*new_apn_ie_len = gbcfg.core_apn_size + 2;
-		msgb_resize_area(msg, apn, apn_len, gbcfg.core_apn_size);
+		gprs_msgb_resize_area(msg, apn, apn_len, gbcfg.core_apn_size);
 		memcpy(apn, gbcfg.core_apn, gbcfg.core_apn_size);
 		hdr->apn_len = gbcfg.core_apn_size;
 	}
@@ -1411,7 +1288,7 @@ static int gbprox_relay2sgsn(struct msgb *old_msg,
 {
 	/* create a copy of the message so the old one can
 	 * be free()d safely when we return from gbprox_rcvmsg() */
-	struct msgb *msg = msgb_copy(old_msg, "msgb_relay2sgsn");
+	struct msgb *msg = gprs_msgb_copy(old_msg, "msgb_relay2sgsn");
 	int rc;
 
 	gbprox_patch_bssgp_message(msg, peer, 0);
@@ -1437,7 +1314,7 @@ static int gbprox_relay2peer(struct msgb *old_msg, struct gbproxy_peer *peer,
 {
 	/* create a copy of the message so the old one can
 	 * be free()d safely when we return from gbprox_rcvmsg() */
-	struct msgb *msg = msgb_copy(old_msg, "msgb_relay2peer");
+	struct msgb *msg = gprs_msgb_copy(old_msg, "msgb_relay2peer");
 	int rc;
 
 	DEBUGP(DGPRS, "NSEI=%u proxying SGSN->BSS (NS_BVCI=%u, NSEI=%u)\n",
diff --git a/openbsc/src/gprs/gb_proxy_vty.c b/openbsc/src/gprs/gb_proxy_vty.c
index 0be251978..29494c6a8 100644
--- a/openbsc/src/gprs/gb_proxy_vty.c
+++ b/openbsc/src/gprs/gb_proxy_vty.c
@@ -32,6 +32,7 @@
 
 #include <openbsc/debug.h>
 #include <openbsc/gb_proxy.h>
+#include <openbsc/gprs_utils.h>
 #include <openbsc/vty.h>
 
 #include <osmocom/vty/command.h>
@@ -92,7 +93,7 @@ static int config_write_gbproxy(struct vty *vty)
 	       if (g_cfg->core_apn_size > 0) {
 		       char str[500] = {0};
 		       vty_out(vty, " core-access-point-name %s",
-			       gbprox_apn_to_str(str, g_cfg->core_apn,
+			       gprs_apn_to_str(str, g_cfg->core_apn,
 						 g_cfg->core_apn_size));
 	       } else {
 		       vty_out(vty, " core-access-point-name none");
@@ -229,7 +230,7 @@ static int set_core_apn(struct vty *vty, const char *apn, const char *filter)
 		g_cfg->core_apn =
 			talloc_realloc_size(NULL, g_cfg->core_apn, apn_len + 1);
 		g_cfg->core_apn_size =
-			gbprox_str_to_apn(g_cfg->core_apn, apn, apn_len + 1);
+			gprs_str_to_apn(g_cfg->core_apn, apn, apn_len + 1);
 	}
 
 	return CMD_SUCCESS;
diff --git a/openbsc/src/gprs/gprs_utils.c b/openbsc/src/gprs/gprs_utils.c
new file mode 100644
index 000000000..8b82f2506
--- /dev/null
+++ b/openbsc/src/gprs/gprs_utils.c
@@ -0,0 +1,152 @@
+/* GPRS utility functions */
+
+/* (C) 2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2010-2014 by On-Waves
+ * (C) 2013 by Holger Hans Peter Freyther
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * 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,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <openbsc/gprs_utils.h>
+
+#include <osmocom/core/msgb.h>
+#include <osmocom/gprs/gprs_ns.h>
+
+#include <string.h>
+
+/* FIXME: this needs to go to libosmocore/msgb.c */
+struct msgb *gprs_msgb_copy(const struct msgb *msg, const char *name)
+{
+	struct libgb_msgb_cb *old_cb, *new_cb;
+	struct msgb *new_msg;
+
+	new_msg = msgb_alloc(msg->data_len, name);
+	if (!new_msg)
+		return NULL;
+
+	/* copy data */
+	memcpy(new_msg->_data, msg->_data, new_msg->data_len);
+
+	/* copy header */
+	new_msg->len = msg->len;
+	new_msg->data += msg->data - msg->_data;
+	new_msg->head += msg->head - msg->_data;
+	new_msg->tail += msg->tail - msg->_data;
+
+	new_msg->l1h = new_msg->_data + (msg->l1h - msg->_data);
+	new_msg->l2h = new_msg->_data + (msg->l2h - msg->_data);
+	new_msg->l3h = new_msg->_data + (msg->l3h - msg->_data);
+	new_msg->l4h = new_msg->_data + (msg->l4h - msg->_data);
+
+	/* copy GB specific data */
+	old_cb = LIBGB_MSGB_CB(msg);
+	new_cb = LIBGB_MSGB_CB(new_msg);
+
+	new_cb->bssgph = new_msg->_data + (old_cb->bssgph - msg->_data);
+	new_cb->llch = new_msg->_data + (old_cb->llch - msg->_data);
+
+	/* bssgp_cell_id is a pointer into the old msgb, so we need to make
+	 * it a pointer into the new msgb */
+	new_cb->bssgp_cell_id = new_msg->_data + (old_cb->bssgp_cell_id - msg->_data);
+	new_cb->nsei = old_cb->nsei;
+	new_cb->bvci = old_cb->bvci;
+	new_cb->tlli = old_cb->tlli;
+
+	return new_msg;
+}
+
+/* TODO: Move this to libosmocore/msgb.c */
+int gprs_msgb_resize_area(struct msgb *msg, uint8_t *area,
+			    size_t old_size, size_t new_size)
+{
+	int rc;
+	uint8_t *rest = area + old_size;
+	int rest_len = msg->len - old_size - (area - msg->data);
+	int delta_size = (int)new_size - (int)old_size;
+
+	if (delta_size == 0)
+		return 0;
+
+	if (delta_size > 0) {
+		rc = msgb_trim(msg, msg->len + delta_size);
+		if (rc < 0)
+			return rc;
+	}
+
+	memmove(area + new_size, area + old_size, rest_len);
+
+	if (msg->l1h >= rest)
+		msg->l1h += delta_size;
+	if (msg->l2h >= rest)
+		msg->l2h += delta_size;
+	if (msg->l3h >= rest)
+		msg->l3h += delta_size;
+	if (msg->l4h >= rest)
+		msg->l4h += delta_size;
+
+	if (delta_size < 0)
+		msgb_trim(msg, msg->len + delta_size);
+
+	return 0;
+}
+
+/* TODO: Move these conversion functions to a utils file. */
+char * gprs_apn_to_str(char *out_str, const uint8_t *apn_enc, size_t rest_chars)
+{
+	char *str = out_str;
+
+	while (rest_chars > 0 && apn_enc[0]) {
+		size_t label_size = apn_enc[0];
+		if (label_size + 1 > rest_chars)
+			return NULL;
+
+		memmove(str, apn_enc + 1, label_size);
+		str += label_size;
+		rest_chars -= label_size + 1;
+		apn_enc += label_size + 1;
+
+		if (rest_chars)
+			*(str++) = '.';
+	}
+	str[0] = '\0';
+
+	return out_str;
+}
+
+int gprs_str_to_apn(uint8_t *apn_enc, const char *str, size_t max_chars)
+{
+	uint8_t *last_len_field = apn_enc;
+	int len = 1;
+	apn_enc += 1;
+
+	while (str[0]) {
+		if (str[0] == '.') {
+			*last_len_field = (apn_enc - last_len_field) - 1;
+			last_len_field = apn_enc;
+		} else {
+			*apn_enc = str[0];
+		}
+		apn_enc += 1;
+		str += 1;
+		len += 1;
+		if (len > max_chars)
+			return -1;
+	}
+
+	*last_len_field = (apn_enc - last_len_field) - 1;
+
+	return len;
+}
+