move openbsc/* to repos root

This is the first step in creating this repository from the legacy openbsc.git.

Like all other Osmocom repositories, keep the autoconf and automake files in
the repository root. openbsc.git has been the sole exception, which ends now.

Change-Id: I9c6f2a448d9cb1cc088cf1cf6918b69d7e69b4e7

1 files changed, 259 insertions, 0 deletions

diff --git a/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c b/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c
new file mode 100644
index 000000000..633fa87d0
--- /dev/null
+++ b/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c
@@ -0,0 +1,259 @@
+/* Handling for loading a re-write file/database */
+/*
+ * (C) 2013 by On-Waves
+ * (C) 2013 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * 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/nat_rewrite_trie.h>
+#include <openbsc/debug.h>
+#include <openbsc/vty.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+#define CHECK_IS_DIGIT_OR_FAIL(prefix, pos)						\
+	if (!isdigit(prefix[pos]) && prefix[pos] != '+') {				\
+			LOGP(DNAT, LOGL_ERROR,						\
+				"Prefix(%s) contains non ascii text at(%d=%c)\n",	\
+				prefix, pos, prefix[pos]);				\
+			goto fail;							\
+	}
+#define TO_INT(c) \
+	((c) == '+' ? 10 : ((c - '0') % 10))
+
+static void insert_rewrite_node(struct nat_rewrite_rule *rule, struct nat_rewrite *root)
+{
+	struct nat_rewrite_rule *new = &root->rule;
+
+	const int len = strlen(rule->prefix);
+	int i;
+
+	if (len <= 0) {
+		LOGP(DNAT, LOGL_ERROR, "An empty prefix does not make sense.\n");
+		goto fail;
+	}
+
+	for (i = 0; i < len - 1; ++i) {
+		int pos;
+
+		/* check if the input is valid */
+		CHECK_IS_DIGIT_OR_FAIL(rule->prefix, i);
+
+		/* check if the next node is already valid */
+		pos = TO_INT(rule->prefix[i]);
+		if (!new->rules[pos]) {
+			new->rules[pos] = talloc_zero(root, struct nat_rewrite_rule);
+			if (!new->rules[pos]) {
+				LOGP(DNAT, LOGL_ERROR,
+					"Failed to allocate memory.\n");
+				goto fail;
+			}
+
+			new->rules[pos]->empty = 1;
+		}
+
+		/* we continue here */
+		new = new->rules[pos];
+	}
+
+	/* new now points to the place where we want to add it */
+	int pos;
+
+	/* check if the input is valid */
+	CHECK_IS_DIGIT_OR_FAIL(rule->prefix, (len - 1));
+
+	/* check if the next node is already valid */
+	pos = TO_INT(rule->prefix[len - 1]);
+	if (!new->rules[pos])
+		new->rules[pos] = rule;
+	else if (new->rules[pos]->empty) {
+		/* copy over entries */
+		new->rules[pos]->empty = 0;
+		memcpy(new->rules[pos]->prefix, rule->prefix, sizeof(rule->prefix));
+		memcpy(new->rules[pos]->rewrite, rule->rewrite, sizeof(rule->rewrite));
+		talloc_free(rule);
+	} else {
+		LOGP(DNAT, LOGL_ERROR,
+			"Prefix(%s) is already installed\n", rule->prefix);
+		goto fail;
+	}
+
+	root->prefixes += 1;
+	return;
+
+fail:
+	talloc_free(rule);
+	return;
+}
+
+static void handle_line(struct nat_rewrite *rewrite, char *line)
+{
+	char *split;
+	struct nat_rewrite_rule *rule;
+	size_t size_prefix, size_end, len;
+
+
+	/* Find the ',' in the line */
+	len = strlen(line);
+	split = strstr(line, ",");
+	if (!split) {
+		LOGP(DNAT, LOGL_ERROR, "Line doesn't contain ','\n");
+		return;
+	}
+
+	/* Check if there is space for the rewrite rule */
+	size_prefix = split - line;
+	if (len - size_prefix <= 2) {
+		LOGP(DNAT, LOGL_ERROR, "No rewrite available.\n");
+		return;
+	}
+
+	/* Continue after the ',' to the end */
+	split = &line[size_prefix + 1];
+	size_end = strlen(split) - 1;
+
+	/* Check if both strings can fit into the static array */
+	if (size_prefix > sizeof(rule->prefix) - 1) {
+		LOGP(DNAT, LOGL_ERROR,
+			"Prefix is too long with %zu\n", size_prefix);
+		return;
+	}
+
+	if (size_end > sizeof(rule->rewrite) - 1) {
+		LOGP(DNAT, LOGL_ERROR,
+			"Rewrite is too long with %zu on %s\n",
+			size_end, &line[size_prefix + 1]);
+		return;
+	}
+
+	/* Now create the entry and insert it into the trie */
+	rule = talloc_zero(rewrite, struct nat_rewrite_rule);
+	if (!rule) {
+		LOGP(DNAT, LOGL_ERROR, "Can not allocate memory\n");
+		return;
+	}
+
+	memcpy(rule->prefix, line, size_prefix);
+	assert(size_prefix < sizeof(rule->prefix));
+	rule->prefix[size_prefix] = '\0';
+
+	memcpy(rule->rewrite, split, size_end);
+	assert(size_end < sizeof(rule->rewrite));
+	rule->rewrite[size_end] = '\0';
+
+	/* now insert and balance the tree */
+	insert_rewrite_node(rule, rewrite);
+}
+
+struct nat_rewrite *nat_rewrite_parse(void *ctx, const char *filename)
+{
+	FILE *file;
+	char *line = NULL;
+	size_t n = 0;
+	struct nat_rewrite *res;
+
+	file = fopen(filename, "r");
+	if (!file)
+		return NULL;
+
+	res = talloc_zero(ctx, struct nat_rewrite);
+	if (!res) {
+		fclose(file);
+		return NULL;
+	}
+
+	/* mark the root as empty */
+	res->rule.empty = 1;
+
+	while (getline(&line, &n, file) != -1) {
+		handle_line(res, line);
+	}
+
+	free(line);
+	fclose(file);
+	return res;
+}
+
+/**
+ * Simple find that tries to do a longest match...
+ */
+struct nat_rewrite_rule *nat_rewrite_lookup(struct nat_rewrite *rewrite,
+					const char *prefix)
+{
+	struct nat_rewrite_rule *rule = &rewrite->rule;
+	struct nat_rewrite_rule *last = NULL;
+	const int len = OSMO_MIN(strlen(prefix), (sizeof(rule->prefix) - 1));
+	int i;
+
+	for (i = 0; rule && i < len; ++i) {
+		int pos;
+
+		CHECK_IS_DIGIT_OR_FAIL(prefix, i);
+		pos = TO_INT(prefix[i]);
+
+		rule = rule->rules[pos];
+		if (rule && !rule->empty)
+			last = rule;
+	}
+
+	return last;
+
+fail:
+	return NULL;
+}
+
+static void nat_rewrite_dump_rec(struct nat_rewrite_rule *rule)
+{
+	int i;
+	if (!rule->empty)
+		printf("%s,%s\n", rule->prefix, rule->rewrite);
+
+	for (i = 0; i < ARRAY_SIZE(rule->rules); ++i) {
+		if (!rule->rules[i])
+			continue;
+		nat_rewrite_dump_rec(rule->rules[i]);
+	}
+}
+
+void nat_rewrite_dump(struct nat_rewrite *rewrite)
+{
+	nat_rewrite_dump_rec(&rewrite->rule);
+}
+
+static void nat_rewrite_dump_rec_vty(struct vty *vty, struct nat_rewrite_rule *rule)
+{
+	int i;
+	if (!rule->empty)
+		vty_out(vty, "%s,%s%s", rule->prefix, rule->rewrite, VTY_NEWLINE);
+
+	for (i = 0; i < ARRAY_SIZE(rule->rules); ++i) {
+		if (!rule->rules[i])
+			continue;
+		nat_rewrite_dump_rec_vty(vty, rule->rules[i]);
+	}
+}
+
+void nat_rewrite_dump_vty(struct vty *vty, struct nat_rewrite *rewrite)
+{
+	nat_rewrite_dump_rec_vty(vty, &rewrite->rule);
+}