internal/wycheproof: skip truncated SHA-512 RSAPSS tests for boring

On the boringcrypto builder, skip the RSAPSS tests that use the
truncated SHA-512 hashes, since boringcrypto does not support them.

Fixes #52670

Change-Id: I8caecd0f34eb6d2740372db2b641563e3965ac7c
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/404654
Run-TryBot: Roland Shoemaker <roland@golang.org>
Auto-Submit: Roland Shoemaker <roland@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>

internal/wycheproof/boring.go

diff --git a/internal/wycheproof/boring.go b/internal/wycheproof/boring.go
new file mode 100644
index 0000000..aefa3ab
--- /dev/null
+++ b/internal/wycheproof/boring.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build boringcrypto
+
+package wycheproof
+
+const boringcryptoEnabled = true

internal/wycheproof/notboring.go

diff --git a/internal/wycheproof/notboring.go b/internal/wycheproof/notboring.go
new file mode 100644
index 0000000..746af13
--- /dev/null
+++ b/internal/wycheproof/notboring.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !boringcrypto
+
+package wycheproof
+
+const boringcryptoEnabled = false

internal/wycheproof/rsa_pss_test.go

diff --git a/internal/wycheproof/rsa_pss_test.go b/internal/wycheproof/rsa_pss_test.go
index 365ca92..2ad9a43 100644
--- a/internal/wycheproof/rsa_pss_test.go
+++ b/internal/wycheproof/rsa_pss_test.go
@@ -112,17 +112,22 @@
 	// works deterministically to auto-detect the length when
 	// verifying, so these tests actually pass as they should.
 	filesOverrideToPassZeroSLen := map[string][]int{
-		"rsa_pss_2048_sha1_mgf1_20_test.json":       []int{46, 47},
-		"rsa_pss_2048_sha256_mgf1_0_test.json":      []int{67, 68},
-		"rsa_pss_2048_sha256_mgf1_32_test.json":     []int{67, 68},
-		"rsa_pss_2048_sha512_256_mgf1_28_test.json": []int{13, 14, 15},
-		"rsa_pss_2048_sha512_256_mgf1_32_test.json": []int{13, 14},
-		"rsa_pss_3072_sha256_mgf1_32_test.json":     []int{67, 68},
-		"rsa_pss_4096_sha256_mgf1_32_test.json":     []int{67, 68},
-		"rsa_pss_4096_sha512_mgf1_32_test.json":     []int{136, 137},
+		"rsa_pss_2048_sha1_mgf1_20_test.json":   []int{46, 47},
+		"rsa_pss_2048_sha256_mgf1_0_test.json":  []int{67, 68},
+		"rsa_pss_2048_sha256_mgf1_32_test.json": []int{67, 68},
+		"rsa_pss_3072_sha256_mgf1_32_test.json": []int{67, 68},
+		"rsa_pss_4096_sha256_mgf1_32_test.json": []int{67, 68},
+		"rsa_pss_4096_sha512_mgf1_32_test.json": []int{136, 137},
 		// "rsa_pss_misc_test.json": nil,  // TODO: This ones seems to be broken right now, but can enable later on.
 	}
 
+	if !boringcryptoEnabled {
+		// boringcrypto doesn't support the truncated SHA-512 hashes, so only
+		// test them if boringcrypto isn't enabled.
+		filesOverrideToPassZeroSLen["rsa_pss_2048_sha512_256_mgf1_28_test.json"] = []int{13, 14, 15}
+		filesOverrideToPassZeroSLen["rsa_pss_2048_sha512_256_mgf1_32_test.json"] = []int{13, 14}
+	}
+
 	for f := range filesOverrideToPassZeroSLen {
 		var root Root
 		readTestVector(t, f, &root)