Move struct apn_ctx and APN related definitions to its own file

This allows further shrinking of gprs_sgsn.{c,h} and also being able to
use GSM_APN_LENGTH on different headers easily (needed by follow-up
patch).

Change-Id: Id225ed8b84e1376f4a30f17dd4b153b6b1a6efa8

8 files changed, 154 insertions, 113 deletions

diff --git a/include/osmocom/sgsn/Makefile.am b/include/osmocom/sgsn/Makefile.am
index fc4f5978c..4d43c6dde 100644
--- a/include/osmocom/sgsn/Makefile.am
+++ b/include/osmocom/sgsn/Makefile.am
@@ -1,4 +1,5 @@
 noinst_HEADERS = \
+	apn.h \
 	common.h \
 	crc24.h \
 	debug.h \
diff --git a/include/osmocom/sgsn/apn.h b/include/osmocom/sgsn/apn.h
new file mode 100644
index 000000000..adf62e21f
--- /dev/null
+++ b/include/osmocom/sgsn/apn.h
@@ -0,0 +1,22 @@
+#pragma once
+
+#include <osmocom/core/linuxlist.h>
+
+struct sgsn_ggsn_ctx;
+
+#define GSM_APN_LENGTH 102
+
+extern struct llist_head sgsn_apn_ctxts;
+
+struct apn_ctx {
+	struct llist_head list;
+	struct sgsn_ggsn_ctx *ggsn;
+	char *name;
+	char *imsi_prefix;
+	char *description;
+};
+
+struct apn_ctx *sgsn_apn_ctx_find_alloc(const char *name, const char *imsi_prefix);
+void sgsn_apn_ctx_free(struct apn_ctx *actx);
+struct apn_ctx *sgsn_apn_ctx_by_name(const char *name, const char *imsi_prefix);
+struct apn_ctx *sgsn_apn_ctx_match(const char *name, const char *imsi_prefix);
diff --git a/include/osmocom/sgsn/gprs_sgsn.h b/include/osmocom/sgsn/gprs_sgsn.h
index 541d854ae..6d51b303e 100644
--- a/include/osmocom/sgsn/gprs_sgsn.h
+++ b/include/osmocom/sgsn/gprs_sgsn.h
@@ -14,10 +14,10 @@
 #include <osmocom/gsm/protocol/gsm_23_003.h>
 #include <osmocom/crypt/auth.h>
 
+#include <osmocom/sgsn/apn.h>
 #include <osmocom/sgsn/gprs_subscriber.h>
 
 #define GSM_EXTENSION_LENGTH 15
-#define GSM_APN_LENGTH 102
 
 struct gprs_llc_lle;
 struct ctrl_handle;
@@ -362,21 +362,7 @@ struct sgsn_pdp_ctx *sgsn_pdp_ctx_alloc(struct sgsn_mm_ctx *mm,
 void sgsn_pdp_ctx_terminate(struct sgsn_pdp_ctx *pdp);
 void sgsn_pdp_ctx_free(struct sgsn_pdp_ctx *pdp);
 
-struct apn_ctx {
-	struct llist_head list;
-	struct sgsn_ggsn_ctx *ggsn;
-	char *name;
-	char *imsi_prefix;
-	char *description;
-};
-
-struct apn_ctx *sgsn_apn_ctx_find_alloc(const char *name, const char *imsi_prefix);
-void sgsn_apn_ctx_free(struct apn_ctx *actx);
-struct apn_ctx *sgsn_apn_ctx_by_name(const char *name, const char *imsi_prefix);
-struct apn_ctx *sgsn_apn_ctx_match(const char *name, const char *imsi_prefix);
-
 extern struct llist_head sgsn_mm_ctxts;
-extern struct llist_head sgsn_apn_ctxts;
 extern struct llist_head sgsn_pdp_ctxts;
 
 uint32_t sgsn_alloc_ptmsi(void);
diff --git a/include/osmocom/sgsn/gprs_subscriber.h b/include/osmocom/sgsn/gprs_subscriber.h
index a961c4581..2e53bdf26 100644
--- a/include/osmocom/sgsn/gprs_subscriber.h
+++ b/include/osmocom/sgsn/gprs_subscriber.h
@@ -6,6 +6,8 @@
 #include <osmocom/core/linuxlist.h>
 #include <osmocom/gsm/protocol/gsm_23_003.h>
 
+#include <osmocom/sgsn/apn.h>
+
 struct sgsn_instance;
 struct sgsn_mm_ctx;
 
diff --git a/src/sgsn/Makefile.am b/src/sgsn/Makefile.am
index 638eaccd6..ba752ad95 100644
--- a/src/sgsn/Makefile.am
+++ b/src/sgsn/Makefile.am
@@ -40,6 +40,7 @@ bin_PROGRAMS = \
 	$(NULL)
 
 osmo_sgsn_SOURCES = \
+	apn.c \
 	gprs_bssgp.c \
 	gprs_gmm_attach.c \
 	gprs_gmm.c \
diff --git a/src/sgsn/apn.c b/src/sgsn/apn.c
new file mode 100644
index 000000000..d6d537204
--- /dev/null
+++ b/src/sgsn/apn.c
@@ -0,0 +1,126 @@
+/* APN contexts */
+
+/* (C) 2009-2015 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2010 by On-Waves
+ * (C) 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * 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 <string.h>
+#include <talloc.h>
+
+#include <osmocom/sgsn/apn.h>
+
+extern void *tall_sgsn_ctx;
+
+LLIST_HEAD(sgsn_apn_ctxts);
+
+static struct apn_ctx *sgsn_apn_ctx_alloc(const char *ap_name, const char *imsi_prefix)
+{
+	struct apn_ctx *actx;
+
+	actx = talloc_zero(tall_sgsn_ctx, struct apn_ctx);
+	if (!actx)
+		return NULL;
+	actx->name = talloc_strdup(actx, ap_name);
+	actx->imsi_prefix = talloc_strdup(actx, imsi_prefix);
+
+	llist_add_tail(&actx->list, &sgsn_apn_ctxts);
+
+	return actx;
+}
+
+void sgsn_apn_ctx_free(struct apn_ctx *actx)
+{
+	llist_del(&actx->list);
+	talloc_free(actx);
+}
+
+struct apn_ctx *sgsn_apn_ctx_match(const char *name, const char *imsi)
+{
+	struct apn_ctx *actx;
+	struct apn_ctx *found_actx = NULL;
+	size_t imsi_prio = 0;
+	size_t name_prio = 0;
+	size_t name_req_len = strlen(name);
+
+	llist_for_each_entry(actx, &sgsn_apn_ctxts, list) {
+		size_t name_ref_len, imsi_ref_len;
+		const char *name_ref_start, *name_match_start;
+
+		imsi_ref_len = strlen(actx->imsi_prefix);
+		if (strncmp(actx->imsi_prefix, imsi, imsi_ref_len) != 0)
+			continue;
+
+		if (imsi_ref_len < imsi_prio)
+			continue;
+
+		/* IMSI matches */
+
+		name_ref_start = &actx->name[0];
+		if (name_ref_start[0] == '*') {
+			/* Suffix match */
+			name_ref_start += 1;
+			name_ref_len = strlen(name_ref_start);
+			if (name_ref_len > name_req_len)
+				continue;
+		} else {
+			name_ref_len = strlen(name_ref_start);
+			if (name_ref_len != name_req_len)
+				continue;
+		}
+
+		name_match_start = name + (name_req_len - name_ref_len);
+		if (strcasecmp(name_match_start, name_ref_start) != 0)
+			continue;
+
+		/* IMSI and name match */
+
+		if (imsi_ref_len == imsi_prio && name_ref_len < name_prio)
+			/* Lower priority, skip */
+			continue;
+
+		imsi_prio = imsi_ref_len;
+		name_prio = name_ref_len;
+		found_actx = actx;
+	}
+	return found_actx;
+}
+
+struct apn_ctx *sgsn_apn_ctx_by_name(const char *name, const char *imsi_prefix)
+{
+	struct apn_ctx *actx;
+
+	llist_for_each_entry(actx, &sgsn_apn_ctxts, list) {
+		if (strcasecmp(name, actx->name) == 0 &&
+		    strcasecmp(imsi_prefix, actx->imsi_prefix) == 0)
+			return actx;
+	}
+	return NULL;
+}
+
+struct apn_ctx *sgsn_apn_ctx_find_alloc(const char *name, const char *imsi_prefix)
+{
+	struct apn_ctx *actx;
+
+	actx = sgsn_apn_ctx_by_name(name, imsi_prefix);
+	if (!actx)
+		actx = sgsn_apn_ctx_alloc(name, imsi_prefix);
+
+	return actx;
+}
diff --git a/src/sgsn/gprs_sgsn.c b/src/sgsn/gprs_sgsn.c
index ea0786282..cdfa02955 100644
--- a/src/sgsn/gprs_sgsn.c
+++ b/src/sgsn/gprs_sgsn.c
@@ -64,7 +64,6 @@ extern void *tall_sgsn_ctx;
 extern struct osmo_tdef sgsn_T_defs[];
 
 LLIST_HEAD(sgsn_mm_ctxts);
-LLIST_HEAD(sgsn_apn_ctxts);
 LLIST_HEAD(sgsn_pdp_ctxts);
 
 const struct value_string sgsn_ran_type_names[] = {
@@ -533,103 +532,6 @@ void sgsn_pdp_ctx_free(struct sgsn_pdp_ctx *pdp)
 	talloc_free(pdp);
 }
 
-/* APN contexts */
-
-static struct apn_ctx *sgsn_apn_ctx_alloc(const char *ap_name, const char *imsi_prefix)
-{
-	struct apn_ctx *actx;
-
-	actx = talloc_zero(tall_sgsn_ctx, struct apn_ctx);
-	if (!actx)
-		return NULL;
-	actx->name = talloc_strdup(actx, ap_name);
-	actx->imsi_prefix = talloc_strdup(actx, imsi_prefix);
-
-	llist_add_tail(&actx->list, &sgsn_apn_ctxts);
-
-	return actx;
-}
-
-void sgsn_apn_ctx_free(struct apn_ctx *actx)
-{
-	llist_del(&actx->list);
-	talloc_free(actx);
-}
-
-struct apn_ctx *sgsn_apn_ctx_match(const char *name, const char *imsi)
-{
-	struct apn_ctx *actx;
-	struct apn_ctx *found_actx = NULL;
-	size_t imsi_prio = 0;
-	size_t name_prio = 0;
-	size_t name_req_len = strlen(name);
-
-	llist_for_each_entry(actx, &sgsn_apn_ctxts, list) {
-		size_t name_ref_len, imsi_ref_len;
-		const char *name_ref_start, *name_match_start;
-
-		imsi_ref_len = strlen(actx->imsi_prefix);
-		if (strncmp(actx->imsi_prefix, imsi, imsi_ref_len) != 0)
-			continue;
-
-		if (imsi_ref_len < imsi_prio)
-			continue;
-
-		/* IMSI matches */
-
-		name_ref_start = &actx->name[0];
-		if (name_ref_start[0] == '*') {
-			/* Suffix match */
-			name_ref_start += 1;
-			name_ref_len = strlen(name_ref_start);
-			if (name_ref_len > name_req_len)
-				continue;
-		} else {
-			name_ref_len = strlen(name_ref_start);
-			if (name_ref_len != name_req_len)
-				continue;
-		}
-
-		name_match_start = name + (name_req_len - name_ref_len);
-		if (strcasecmp(name_match_start, name_ref_start) != 0)
-			continue;
-
-		/* IMSI and name match */
-
-		if (imsi_ref_len == imsi_prio && name_ref_len < name_prio)
-			/* Lower priority, skip */
-			continue;
-
-		imsi_prio = imsi_ref_len;
-		name_prio = name_ref_len;
-		found_actx = actx;
-	}
-	return found_actx;
-}
-
-struct apn_ctx *sgsn_apn_ctx_by_name(const char *name, const char *imsi_prefix)
-{
-	struct apn_ctx *actx;
-
-	llist_for_each_entry(actx, &sgsn_apn_ctxts, list) {
-		if (strcasecmp(name, actx->name) == 0 &&
-		    strcasecmp(imsi_prefix, actx->imsi_prefix) == 0)
-			return actx;
-	}
-	return NULL;
-}
-
-struct apn_ctx *sgsn_apn_ctx_find_alloc(const char *name, const char *imsi_prefix)
-{
-	struct apn_ctx *actx;
-
-	actx = sgsn_apn_ctx_by_name(name, imsi_prefix);
-	if (!actx)
-		actx = sgsn_apn_ctx_alloc(name, imsi_prefix);
-
-	return actx;
-}
-
 uint32_t sgsn_alloc_ptmsi(void)
 {
 	struct sgsn_mm_ctx *mm;
diff --git a/tests/sgsn/Makefile.am b/tests/sgsn/Makefile.am
index 8deec2462..853d8f1b9 100644
--- a/tests/sgsn/Makefile.am
+++ b/tests/sgsn/Makefile.am
@@ -48,6 +48,7 @@ sgsn_test_LDFLAGS = \
 	$(NULL)
 
 sgsn_test_LDADD = \
+	$(top_builddir)/src/sgsn/apn.o \
 	$(top_builddir)/src/sgsn/gprs_bssgp.o \
 	$(top_builddir)/src/sgsn/gprs_llc.o \
 	$(top_builddir)/src/sgsn/gprs_ns.o \