ipsec: fix build with gcc 6

gcc 6.2 and 6.4 fails to compile lib/librte_ipsec/sa.c
with the following errors:
lib/librte_ipsec/sa.c:
 In function inline_outb_tun_pkt_process:
 x86_64-native-linuxapp-gcc/include/rte_memcpy.h:337:2:
 error: array subscript is above array bounds [-Werror=array-bounds]
  rte_mov32((uint8_t *)dst + 1 * 32, (const uint8_t *)src + 1 * 32);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ...

It complains about the following lines of code:
esp_outb_tun_pkt_prepare(struct rte_ipsec_sa *sa, rte_be64_t
        ....
        /* update spi, seqn and iv */
        esph = (struct esp_hdr *)(ph + sa->hdr_len);
        iv = (uint64_t *)(esph + 1);
        rte_memcpy(iv, ivp, sa->iv_len);

While I believe it is a false positive,
it is too excessive to use rte_memcpy() here,
as IV length could be only 0/8/16 bytes.
So introduce small helper function to copy IV and use it
instead of rte_memcpy().

Fixes: 4d7ea3e1459b ("ipsec: implement SA data-path API")

Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>

diff --git a/lib/librte_ipsec/crypto.h b/lib/librte_ipsec/crypto.h
index 61f5c14..b5f2648 100644 (file)
--- a/lib/librte_ipsec/crypto.h
+++ b/lib/librte_ipsec/crypto.h
@@ -76,6 +76,31 @@ gen_iv(uint64_t iv[IPSEC_MAX_IV_QWORD], rte_be64_t sqn)
        iv[1] = 0;
 }
 
+/*
+ * Helper routine to copy IV
+ * Righ now we support only algorithms with IV length equals 0/8/16 bytes.
+ */
+static inline void
+copy_iv(uint64_t dst[IPSEC_MAX_IV_QWORD],
+       const uint64_t src[IPSEC_MAX_IV_QWORD], uint32_t len)
+{
+       RTE_BUILD_BUG_ON(IPSEC_MAX_IV_SIZE != 2 * sizeof(uint64_t));
+
+       switch (len) {
+       case IPSEC_MAX_IV_SIZE:
+               dst[1] = src[1];
+               /* fallthrough */
+       case sizeof(uint64_t):
+               dst[0] = src[0];
+               /* fallthrough */
+       case 0:
+               break;
+       default:
+               /* should never happen */
+               RTE_ASSERT(NULL);
+       }
+}
+
 /*
  * from RFC 4303 3.3.2.1.4:
  * If the ESN option is enabled for the SA, the high-order 32

diff --git a/lib/librte_ipsec/sa.c b/lib/librte_ipsec/sa.c
index 8d4ce1a..5f55c2a 100644 (file)
--- a/lib/librte_ipsec/sa.c
+++ b/lib/librte_ipsec/sa.c
@@ -526,7 +526,7 @@ esp_outb_tun_pkt_prepare(struct rte_ipsec_sa *sa, rte_be64_t sqc,
        /* update spi, seqn and iv */
        esph = (struct esp_hdr *)(ph + sa->hdr_len);
        iv = (uint64_t *)(esph + 1);
-       rte_memcpy(iv, ivp, sa->iv_len);
+       copy_iv(iv, ivp, sa->iv_len);
 
        esph->spi = sa->spi;
        esph->seq = sqn_low32(sqc);
@@ -689,7 +689,7 @@ esp_outb_trs_pkt_prepare(struct rte_ipsec_sa *sa, rte_be64_t sqc,
        /* update spi, seqn and iv */
        esph = (struct esp_hdr *)(ph + uhlen);
        iv = (uint64_t *)(esph + 1);
-       rte_memcpy(iv, ivp, sa->iv_len);
+       copy_iv(iv, ivp, sa->iv_len);
 
        esph->spi = sa->spi;
        esph->seq = sqn_low32(sqc);
@@ -821,7 +821,7 @@ esp_inb_tun_cop_prepare(struct rte_crypto_op *cop,
                ivc = rte_crypto_op_ctod_offset(cop, uint64_t *, sa->iv_ofs);
                ivp = rte_pktmbuf_mtod_offset(mb, uint64_t *,
                        pofs + sizeof(struct esp_hdr));
-               rte_memcpy(ivc, ivp, sa->iv_len);
+               copy_iv(ivc, ivp, sa->iv_len);
        }
        return 0;
 }