Use built-in Camellia in krb5 integration patch; fix CTS doc label

include/openssl/bn.h

@@ -975,10 +975,9 @@ OPENSSL_EXPORT unsigned BN_num_bits_word(BN_ULONG l);
 #define BN_FLG_STATIC_DATA 0x02
 
 // |BN_FLG_CONSTTIME| has been removed and intentionally omitted so code relying
-// on it will not compile unless the flag above is set. Consumers should use the
-// higher-level cryptographic algorithms exposed by other modules. Consumers
-// within the library should call the appropriate timing-sensitive algorithm
-// directly.
+// on it will not compile. External consumers should use the higher-level
+// cryptographic algorithms exposed by other modules. Consumers within the
+// library should call the appropriate timing-sensitive algorithm directly.
 
 
 #if defined(__cplusplus)

include/openssl/modes.h

@@ -29,10 +29,10 @@ typedef void (*cbc128_f)(const uint8_t *in, uint8_t *out, size_t len,
                          const AES_KEY *key, uint8_t ivec[16], int enc);
 
 // CRYPTO_cts128_encrypt encrypts |len| bytes from |in| to |out| in CBC
-// Ciphertext Stealing (CTS) mode (CS1 / RFC 2040 convention: the last two
-// ciphertext blocks are unconditionally swapped, and an exact-block-multiple
-// input is handled as a 16-byte residue). The IV is updated in |ivec|. |key|
-// must have been set up for encryption.
+// Ciphertext Stealing (CTS) mode (CS3 / NIST SP 800-38A Addendum convention:
+// the last two ciphertext blocks are unconditionally swapped, and an
+// exact-block-multiple input is handled as a 16-byte residue). The IV is
+// updated in |ivec|. |key| must have been set up for encryption.
 //
 // Returns the number of bytes written, equal to |len|, on success. Returns
 // zero if |len| <= 16; for inputs of one block or fewer use plain CBC.

tests/ci/integration/krb5_patch/0002-Use-built-in-Camellia-when-building-against-AWS-LC.patch

@@ -0,0 +1,33 @@
+From: AWS-LC integration CI <aws-lc-ci@amazon.com>
+Subject: [PATCH] Use built-in Camellia when building against AWS-LC
+
+AWS-LC does not implement Camellia, so krb5's OpenSSL Camellia
+enc_provider (guarded on K5_OPENSSL_CAMELLIA) cannot link against it.
+Rather than disabling the Camellia enctypes, select krb5's own built-in
+Camellia implementation (K5_BUILTIN_CAMELLIA) when building against
+AWS-LC, detected via OPENSSL_IS_AWSLC from <openssl/opensslv.h> (already
+included by crypto_int.h under CRYPTO_OPENSSL). The built-in sources in
+lib/crypto/builtin/ are always compiled on Unix, so this keeps all
+Camellia enctypes and CMAC checksums fully functional with no changes to
+the crypto test suite.
+
+This mirrors the approach suggested by the krb5 maintainers:
+https://github.com/krb5/krb5/pull/1533#issuecomment-4974308880
+
+---
+diff --git a/src/lib/crypto/krb/crypto_int.h b/src/lib/crypto/krb/crypto_int.h
+index 3629616..fb30d1f 100644
+--- a/src/lib/crypto/krb/crypto_int.h
++++ b/src/lib/crypto/krb/crypto_int.h
+@@ -62,7 +62,11 @@
+ #endif
+
+ #define K5_OPENSSL_AES
++#ifdef OPENSSL_IS_AWSLC
++#define K5_BUILTIN_CAMELLIA
++#else
+ #define K5_OPENSSL_CAMELLIA
++#endif
+ #define K5_OPENSSL_DES
+ #define K5_OPENSSL_HMAC
+ #define K5_OPENSSL_MD5

tests/ci/integration/run_krb5_integration.sh

@@ -82,10 +82,10 @@ function krb5_build() {
 
 # Run krb5's crypto unit tests. The full `make check` from the top of the tree
 # spins up KDCs and exercises end-to-end Kerberos flows, which requires Python
-# and additional CI plumbing. We build the test binaries then run the subset
-# that exercises the AWS-LC backend (AES-CTS, HMAC, SHA-2, PRF, key derivation)
-# without relying on Camellia (which AWS-LC doesn't implement) or DES
-# behaviours that differ from stock OpenSSL.
+# and additional CI plumbing. We build the test binaries then run the crypto
+# test subset, which exercises the AWS-LC backend (AES-CTS, HMAC, SHA-2, PRF,
+# key derivation) alongside krb5's built-in primitives (Camellia is served by
+# the built-in implementation when building against AWS-LC).
 function krb5_run_tests() {
   pushd "${KRB5_SRC_FOLDER}/src/lib/crypto"
 
@@ -95,11 +95,6 @@ function krb5_run_tests() {
   ln -sf "${AWS_LC_INSTALL_FOLDER}/lib/libcrypto.so" "../../lib/libcrypto.so"
   ln -sf "${AWS_LC_INSTALL_FOLDER}/lib/libcrypto.so.1" "../../lib/libcrypto.so.1"
 
-  # The camellia-test binary is a no-op (exits 0) when Camellia is disabled,
-  # but `make check` compares its stdout to a golden file. Truncate the golden
-  # file so the comparison succeeds.
-  : > crypto_tests/camellia-expect-vt.txt
-
   make -j "${NUM_CPU_THREADS}" check
   popd
 }