[dpdk-dev] [PATCH] examples/ipsec-secgw: fix SPD no-match is misinterpreted

[Konstantin Ananyev]

acl_classify() returns zero value when no matching rule was found.
Currently ipsec-secgw treats it as a valid SPI value, though it has
to discard such packets.
Error could be easily observed by sending outbound unmatched packets,
user will see something like that in the log:
IPSEC: No cryptodev: core 7, cipher_algo 0, auth_algo 0, aead_algo 0

To fix it we need to treat packets with zero result from acl_classify()
as invalid ones. Also we can change DISCARD and BYPASS values to
simplify checks and save some extra space for valid SPI values.

Fixes: 906257e965b7 ("examples/ipsec-secgw: support IPv6")
Fixes: 2a5106af132b ("examples/ipsec-secgw: fix corner case for SPI value")
Cc: stable at dpdk.org

Signed-off-by: Konstantin Ananyev <konstantin.ananyev at intel.com>
---
 examples/ipsec-secgw/ipsec-secgw.c | 12 ++++++------
 examples/ipsec-secgw/ipsec.h       |  6 ++----
 examples/ipsec-secgw/sp4.c         | 11 ++++++++---
 examples/ipsec-secgw/sp6.c         | 11 ++++++++---
 4 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/examples/ipsec-secgw/ipsec-secgw.c b/examples/ipsec-secgw/ipsec-secgw.c
index ffbd00b08..59e084234 100644
--- a/examples/ipsec-secgw/ipsec-secgw.c
+++ b/examples/ipsec-secgw/ipsec-secgw.c
@@ -438,11 +438,11 @@ inbound_sp_sa(struct sp_ctx *sp, struct sa_ctx *sa, struct traffic_type *ip,
 	for (i = 0; i < ip->num; i++) {
 		m = ip->pkts[i];
 		res = ip->res[i];
-		if (res & BYPASS) {
+		if (res == BYPASS) {
 			ip->pkts[j++] = m;
 			continue;
 		}
-		if (res & DISCARD) {
+		if (res == DISCARD) {
 			rte_pktmbuf_free(m);
 			continue;
 		}
@@ -453,7 +453,7 @@ inbound_sp_sa(struct sp_ctx *sp, struct sa_ctx *sa, struct traffic_type *ip,
 			continue;
 		}
 
-		sa_idx = ip->res[i] & PROTECT_MASK;
+		sa_idx = ip->res[i];
 		if (sa_idx >= IPSEC_SA_MAX_ENTRIES ||
 				!inbound_sa_check(sa, m, sa_idx)) {
 			rte_pktmbuf_free(m);
@@ -541,10 +541,10 @@ outbound_sp(struct sp_ctx *sp, struct traffic_type *ip,
 	j = 0;
 	for (i = 0; i < ip->num; i++) {
 		m = ip->pkts[i];
-		sa_idx = ip->res[i] & PROTECT_MASK;
-		if (ip->res[i] & DISCARD)
+		sa_idx = ip->res[i];
+		if (sa_idx == DISCARD)
 			rte_pktmbuf_free(m);
-		else if (ip->res[i] & BYPASS)
+		else if (sa_idx == BYPASS)
 			ip->pkts[j++] = m;
 		else if (sa_idx < IPSEC_SA_MAX_ENTRIES) {
 			ipsec->res[ipsec->num] = sa_idx;
diff --git a/examples/ipsec-secgw/ipsec.h b/examples/ipsec-secgw/ipsec.h
index 99f49d65f..44daf384b 100644
--- a/examples/ipsec-secgw/ipsec.h
+++ b/examples/ipsec-secgw/ipsec.h
@@ -41,10 +41,8 @@
 #define SPI2IDX(spi) (spi & (IPSEC_SA_MAX_ENTRIES - 1))
 #define INVALID_SPI (0)
 
-#define DISCARD (0x80000000)
-#define BYPASS (0x40000000)
-#define PROTECT_MASK (0x3fffffff)
-#define PROTECT(sa_idx) (SPI2IDX(sa_idx) & PROTECT_MASK) /* SA idx 30 bits */
+#define DISCARD	INVALID_SPI
+#define BYPASS	UINT32_MAX
 
 #define IPSEC_XFORM_MAX 2
 
diff --git a/examples/ipsec-secgw/sp4.c b/examples/ipsec-secgw/sp4.c
index d1dc64bad..bfaddc52e 100644
--- a/examples/ipsec-secgw/sp4.c
+++ b/examples/ipsec-secgw/sp4.c
@@ -99,6 +99,7 @@ parse_sp4_tokens(char **tokens, uint32_t n_tokens,
 
 	uint32_t *ri = NULL; /* rule index */
 	uint32_t ti = 0; /* token index */
+	uint32_t tv;
 
 	uint32_t esp_p = 0;
 	uint32_t protect_p = 0;
@@ -169,8 +170,12 @@ parse_sp4_tokens(char **tokens, uint32_t n_tokens,
 			if (status->status < 0)
 				return;
 
-			rule_ipv4->data.userdata =
-				PROTECT(atoi(tokens[ti]));
+			tv = atoi(tokens[ti]);
+			APP_CHECK(tv != DISCARD && tv != BYPASS, status,
+				"invalid SPI: %s", tokens[ti]);
+			if (status->status < 0)
+				return;
+			rule_ipv4->data.userdata = tv;
 
 			protect_p = 1;
 			continue;
@@ -523,7 +528,7 @@ sp4_spi_present(uint32_t spi, int inbound)
 	}
 
 	for (i = 0; i != num; i++) {
-		if (acr[i].data.userdata == PROTECT(spi))
+		if (acr[i].data.userdata == spi)
 			return i;
 	}
 
diff --git a/examples/ipsec-secgw/sp6.c b/examples/ipsec-secgw/sp6.c
index e67d85aaf..b7fcf7c16 100644
--- a/examples/ipsec-secgw/sp6.c
+++ b/examples/ipsec-secgw/sp6.c
@@ -130,6 +130,7 @@ parse_sp6_tokens(char **tokens, uint32_t n_tokens,
 
 	uint32_t *ri = NULL; /* rule index */
 	uint32_t ti = 0; /* token index */
+	uint32_t tv;
 
 	uint32_t esp_p = 0;
 	uint32_t protect_p = 0;
@@ -202,8 +203,12 @@ parse_sp6_tokens(char **tokens, uint32_t n_tokens,
 			if (status->status < 0)
 				return;
 
-			rule_ipv6->data.userdata =
-				PROTECT(atoi(tokens[ti]));
+			tv = atoi(tokens[ti]);
+			APP_CHECK(tv != DISCARD && tv != BYPASS, status,
+				"invalid SPI: %s", tokens[ti]);
+			if (status->status < 0)
+				return;
+			rule_ipv6->data.userdata = tv;
 
 			protect_p = 1;
 			continue;
@@ -637,7 +642,7 @@ sp6_spi_present(uint32_t spi, int inbound)
 	}
 
 	for (i = 0; i != num; i++) {
-		if (acr[i].data.userdata == PROTECT(spi))
+		if (acr[i].data.userdata == spi)
 			return i;
 	}
 
-- 
2.17.1