From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 9C32B5A0271 for ; Thu, 28 Sep 2023 03:21:08 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=201602; t=1695864064; bh=A5255woyw/RNOY1r0AvdSeKUaCI6iHaA8mom25WCN24=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZKAUnvSV41w3ZO6w2x17IsaF0OX5ziXYvffs2LVGQzslWa9y3GdyEbRlets2Guolq r/esq8WZuRJDKV05G6SWdj4qPkZQwd3KvhU2LCSmuy8CZCHFJDoJtKdEH9zL82zKGt lyptd1Y3Ikcbek/qqMgZ3da3vJytkCLyBWnRFDbc= Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4RwwfS6fXmz4xRj; Thu, 28 Sep 2023 11:21:04 +1000 (AEST) From: David Gibson To: Stefano Brivio , passt-dev@passt.top Subject: [PATCH v2 01/10] siphash: Make siphash functions consistently return 64-bit results Date: Thu, 28 Sep 2023 11:20:53 +1000 Message-ID: <20230928012102.1446180-2-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230928012102.1446180-1-david@gibson.dropbear.id.au> References: <20230928012102.1446180-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: LRZ6MMIDLR7XEYIFU3HIVKJSOBDZBJBY X-Message-ID-Hash: LRZ6MMIDLR7XEYIFU3HIVKJSOBDZBJBY X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: David Gibson X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Some of the siphas_*b() functions return 64-bit results, others 32-bit results, with no obvious pattern. siphash_32b() also appears to do this incorrectly - taking the 64-bit hash value and simply returning it truncated, rather than folding the two halves together. Since SipHash proper is defined to give a 64-bit hash, make all of them return 64-bit results. In the one caller which needs a 32-bit value, tcp_seq_init() do the fold down to 32-bits ourselves. Signed-off-by: David Gibson --- siphash.c | 17 +++++++---------- siphash.h | 6 +++--- tcp.c | 7 ++++--- 3 files changed, 14 insertions(+), 16 deletions(-) diff --git a/siphash.c b/siphash.c index e266e15..20009fe 100644 --- a/siphash.c +++ b/siphash.c @@ -61,7 +61,6 @@ uint64_t v[4] = { 0x736f6d6570736575ULL, 0x646f72616e646f6dULL, \ 0x6c7967656e657261ULL, 0x7465646279746573ULL }; \ uint64_t b = (uint64_t)(len) << 56; \ - uint32_t ret; \ int __i; \ \ do { \ @@ -93,8 +92,6 @@ v[2] ^= 0xff; \ SIPROUND(4); \ b = (v[0] ^ v[1]) ^ (v[2] ^ v[3]); \ - ret = (uint32_t)(b >> 32) ^ (uint32_t)b; \ - (void)ret; \ } while (0) /** @@ -132,12 +129,12 @@ uint64_t siphash_8b(const uint8_t *in, const uint64_t *k) * @in: Input data (two addresses, two ports) * @k: Hash function key, 128 bits * - * Return: 32 bits obtained by XORing the two halves of the 64-bit hash output + * Return: the 64-bit hash output */ /* NOLINTNEXTLINE(clang-diagnostic-unknown-attributes) */ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ /* cppcheck-suppress unusedFunction */ -uint32_t siphash_12b(const uint8_t *in, const uint64_t *k) +uint64_t siphash_12b(const uint8_t *in, const uint64_t *k) { uint32_t *in32 = (uint32_t *)in; uint64_t combined; @@ -151,7 +148,7 @@ uint32_t siphash_12b(const uint8_t *in, const uint64_t *k) b |= *(in32 + 2); POSTAMBLE; - return ret; + return b; } /** @@ -194,7 +191,7 @@ uint64_t siphash_20b(const uint8_t *in, const uint64_t *k) /* NOLINTNEXTLINE(clang-diagnostic-unknown-attributes) */ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ /* cppcheck-suppress unusedFunction */ -uint32_t siphash_32b(const uint8_t *in, const uint64_t *k) +uint64_t siphash_32b(const uint8_t *in, const uint64_t *k) { uint64_t *in64 = (uint64_t *)in; int i; @@ -217,11 +214,11 @@ uint32_t siphash_32b(const uint8_t *in, const uint64_t *k) * @in: Input data (two addresses, two ports) * @k: Hash function key, 128 bits * - * Return: 32 bits obtained by XORing the two halves of the 64-bit hash output + * Return: the 64-bit hash output */ /* NOLINTNEXTLINE(clang-diagnostic-unknown-attributes) */ __attribute__((optimize("-fno-strict-aliasing"))) /* See siphash_8b() */ -uint32_t siphash_36b(const uint8_t *in, const uint64_t *k) +uint64_t siphash_36b(const uint8_t *in, const uint64_t *k) { uint32_t *in32 = (uint32_t *)in; int i; @@ -239,5 +236,5 @@ uint32_t siphash_36b(const uint8_t *in, const uint64_t *k) b |= *in32; POSTAMBLE; - return ret; + return b; } diff --git a/siphash.h b/siphash.h index 5b0d0c3..de04c56 100644 --- a/siphash.h +++ b/siphash.h @@ -7,9 +7,9 @@ #define SIPHASH_H uint64_t siphash_8b(const uint8_t *in, const uint64_t *k); -uint32_t siphash_12b(const uint8_t *in, const uint64_t *k); +uint64_t siphash_12b(const uint8_t *in, const uint64_t *k); uint64_t siphash_20b(const uint8_t *in, const uint64_t *k); -uint32_t siphash_32b(const uint8_t *in, const uint64_t *k); -uint32_t siphash_36b(const uint8_t *in, const uint64_t *k); +uint64_t siphash_32b(const uint8_t *in, const uint64_t *k); +uint64_t siphash_36b(const uint8_t *in, const uint64_t *k); #endif /* SIPHASH_H */ diff --git a/tcp.c b/tcp.c index 2933123..19baba5 100644 --- a/tcp.c +++ b/tcp.c @@ -1826,7 +1826,8 @@ static void tcp_seq_init(const struct ctx *c, struct tcp_tap_conn *conn, .srcport = conn->fport, .dstport = conn->eport, }; - uint32_t ns, seq = 0; + uint64_t hash; + uint32_t ns; if (CONN_V4(conn)) inany_from_af(&aany, AF_INET, &c->ip4.addr); @@ -1834,12 +1835,12 @@ static void tcp_seq_init(const struct ctx *c, struct tcp_tap_conn *conn, inany_from_af(&aany, AF_INET6, &c->ip6.addr); in.dst = aany; - seq = siphash_36b((uint8_t *)&in, c->tcp.hash_secret); + hash = siphash_36b((uint8_t *)&in, c->tcp.hash_secret); /* 32ns ticks, overflows 32 bits every 137s */ ns = (now->tv_sec * 1000000000 + now->tv_nsec) >> 5; - conn->seq_to_tap = seq + ns; + conn->seq_to_tap = ((uint32_t)(hash >> 32) ^ (uint32_t)hash) + ns; } /** -- 2.41.0