[PATCH nft,v4] mergesort: find base value expression type via recursion

[PATCH nft,v4] mergesort: find base value expression type via recursion

[Pablo Neira Ayuso]

Sets that store flags might contain a mixture of values and binary
operations. Find the base value type via recursion to compare the
expressions.

Fixes: 14ee0a979b62 ("src: sort set elements in netlink_get_setelems()")
Fixes: 3926a3369bb5 ("mergesort: unbreak listing with binops")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
v4: Make sure concatenations are listed in a deterministic way via
    concat_expr_msort_value.
    Adjust a few tests after this update since listing differs.

 src/mergesort.c                               | 61 ++++++++++++-------
 .../nft-f/dumps/0012different_defines_0.nft   |  2 +-
 tests/shell/testcases/sets/0055tcpflags_0     | 27 ++++++++
 .../dumps/0037_set_with_inet_service_0.nft    |  8 +--
 .../testcases/sets/dumps/0055tcpflags_0.nft   | 10 +++
 5 files changed, 81 insertions(+), 27 deletions(-)
 create mode 100755 tests/shell/testcases/sets/0055tcpflags_0
 create mode 100644 tests/shell/testcases/sets/dumps/0055tcpflags_0.nft

diff --git a/src/mergesort.c b/src/mergesort.c
index 02094b486aeb..61128f977f04 100644
--- a/src/mergesort.c
+++ b/src/mergesort.c
@@ -12,44 +12,61 @@
 #include <list.h>
 
 static int expr_msort_cmp(const struct expr *e1, const struct expr *e2);
+static void expr_msort_value(const struct expr *expr, mpz_t value);
 
-static int concat_expr_msort_cmp(const struct expr *e1, const struct expr *e2)
+static void concat_expr_msort_value(const struct expr *expr, mpz_t value)
 {
-	struct list_head *l = (&e2->expressions)->next;
-	const struct expr *i1, *i2;
-	int ret;
-
-	list_for_each_entry(i1, &e1->expressions, list) {
-		i2 = list_entry(l, typeof(struct expr), list);
+	const struct expr *i;
+	unsigned int len = 0;
+	char data[512];
 
-		ret = expr_msort_cmp(i1, i2);
-		if (ret)
-			return ret;
+	mpz_init(value);
 
-		l = l->next;
+	list_for_each_entry(i, &expr->expressions, list) {
+		mpz_export_data(data + len, i->value, i->byteorder, i->len);
+		len += i->len;
 	}
 
-	return false;
+	mpz_import_data(value, data, BYTEORDER_HOST_ENDIAN, len);
 }
 
-static int expr_msort_cmp(const struct expr *e1, const struct expr *e2)
+static void expr_msort_value(const struct expr *expr, mpz_t value)
 {
-	switch (e1->etype) {
+	switch (expr->etype) {
 	case EXPR_SET_ELEM:
-		return expr_msort_cmp(e1->key, e2->key);
+		expr_msort_value(expr->key, value);
+		break;
+	case EXPR_BINOP:
+	case EXPR_MAPPING:
+		expr_msort_value(expr->left, value);
+		break;
 	case EXPR_VALUE:
-		return mpz_cmp(e1->value, e2->value);
+		mpz_set(value, expr->value);
+		break;
 	case EXPR_CONCAT:
-		return concat_expr_msort_cmp(e1, e2);
-	case EXPR_MAPPING:
-		return expr_msort_cmp(e1->left, e2->left);
-	case EXPR_BINOP:
-		return expr_msort_cmp(e1->left, e2->left);
+		concat_expr_msort_value(expr, value);
+		break;
 	default:
-		BUG("Unknown expression %s\n", expr_name(e1));
+		BUG("Unknown expression %s\n", expr_name(expr));
 	}
 }
 
+static int expr_msort_cmp(const struct expr *e1, const struct expr *e2)
+{
+	mpz_t value1, value2;
+	int ret;
+
+	mpz_init(value1);
+	mpz_init(value2);
+	expr_msort_value(e1, value1);
+	expr_msort_value(e2, value2);
+	ret = mpz_cmp(value1, value2);
+	mpz_clear(value1);
+	mpz_clear(value2);
+
+	return ret;
+}
+
 static void list_splice_sorted(struct list_head *list, struct list_head *head)
 {
 	struct list_head *h = head->next;
diff --git a/tests/shell/testcases/nft-f/dumps/0012different_defines_0.nft b/tests/shell/testcases/nft-f/dumps/0012different_defines_0.nft
index 7abced868601..28094387ebed 100644
--- a/tests/shell/testcases/nft-f/dumps/0012different_defines_0.nft
+++ b/tests/shell/testcases/nft-f/dumps/0012different_defines_0.nft
@@ -8,7 +8,7 @@ table inet t {
 		ip6 daddr fe0::1 ip6 saddr fe0::2
 		ip saddr vmap { 10.0.0.0 : drop, 10.0.0.2 : accept }
 		ip6 daddr vmap { fe0::1 : drop, fe0::2 : accept }
-		ip6 saddr . ip6 nexthdr { fe0::1 . udp, fe0::2 . tcp }
+		ip6 saddr . ip6 nexthdr { fe0::2 . tcp, fe0::1 . udp }
 		ip daddr . iif vmap { 10.0.0.0 . "lo" : accept }
 		tcp dport 100-222
 		udp dport vmap { 100-222 : accept }
diff --git a/tests/shell/testcases/sets/0055tcpflags_0 b/tests/shell/testcases/sets/0055tcpflags_0
new file mode 100755
index 000000000000..a2b24eb2981b
--- /dev/null
+++ b/tests/shell/testcases/sets/0055tcpflags_0
@@ -0,0 +1,27 @@
+#!/bin/bash
+
+EXPECTED="add table ip test
+
+add set ip test tcp_good_flags { type tcp_flag ; flags constant ; elements = {
+  ( 0 | 0 | 0 |ack| 0 | 0 ),  \
+  ( 0 | 0 | 0 |ack| 0 |urg),  \
+  ( 0 | 0 | 0 |ack|psh| 0 ),  \
+  ( 0 | 0 | 0 |ack|psh|urg),  \
+  ( 0 | 0 |rst| 0 | 0 | 0 ),  \
+  ( 0 | 0 |rst|ack| 0 | 0 ),  \
+  ( 0 | 0 |rst|ack| 0 |urg),  \
+  ( 0 | 0 |rst|ack|psh| 0 ),  \
+  ( 0 | 0 |rst|ack|psh|urg),  \
+  ( 0 |syn| 0 | 0 | 0 | 0 ),  \
+  ( 0 |syn| 0 |ack| 0 | 0 ),  \
+  ( 0 |syn| 0 |ack| 0 |urg),  \
+  ( 0 |syn| 0 |ack|psh| 0 ),  \
+  ( 0 |syn| 0 |ack|psh|urg),  \
+  (fin| 0 | 0 |ack| 0 | 0 ),  \
+  (fin| 0 | 0 |ack| 0 |urg),  \
+  (fin| 0 | 0 |ack|psh| 0 ),  \
+  (fin| 0 | 0 |ack|psh|urg)   \
+} ; }"
+
+set -e
+$NFT -f - <<< $EXPECTED
diff --git a/tests/shell/testcases/sets/dumps/0037_set_with_inet_service_0.nft b/tests/shell/testcases/sets/dumps/0037_set_with_inet_service_0.nft
index 0e85f7c20eba..68b1f7bec4d8 100644
--- a/tests/shell/testcases/sets/dumps/0037_set_with_inet_service_0.nft
+++ b/tests/shell/testcases/sets/dumps/0037_set_with_inet_service_0.nft
@@ -1,11 +1,11 @@
 table inet filter {
 	set myset {
 		type ipv4_addr . inet_proto . inet_service
-		elements = { 192.168.0.12 . tcp . 53,
-			     192.168.0.12 . tcp . 80,
+		elements = { 192.168.0.113 . tcp . 22,
+			     192.168.0.12 . tcp . 53,
 			     192.168.0.12 . udp . 53,
-			     192.168.0.13 . tcp . 80,
-			     192.168.0.113 . tcp . 22 }
+			     192.168.0.12 . tcp . 80,
+			     192.168.0.13 . tcp . 80 }
 	}
 
 	chain forward {
diff --git a/tests/shell/testcases/sets/dumps/0055tcpflags_0.nft b/tests/shell/testcases/sets/dumps/0055tcpflags_0.nft
new file mode 100644
index 000000000000..ffed5426577e
--- /dev/null
+++ b/tests/shell/testcases/sets/dumps/0055tcpflags_0.nft
@@ -0,0 +1,10 @@
+table ip test {
+	set tcp_good_flags {
+		type tcp_flag
+		flags constant
+		elements = { fin | psh | ack | urg, fin | psh | ack, fin | ack | urg, fin | ack, syn | psh | ack | urg,
+			     syn | psh | ack, syn | ack | urg, syn | ack, syn, rst | psh | ack | urg,
+			     rst | psh | ack, rst | ack | urg, rst | ack, rst, psh | ack | urg,
+			     psh | ack, ack | urg, ack }
+	}
+}
-- 
2.20.1