feature: new TLS1.2 + FIPS CRT security policy (#5375)

Co-authored-by: Boquan Fang <boquanfang3@gmail.com>

Author: lrstewart

tests/policy_snapshot/snapshots/AWS-CRT-SDK-TLSv1.2-2025

@@ -0,0 +1,28 @@
+name: AWS-CRT-SDK-TLSv1.2-2025
+min version: TLS1.2
+rules:
+- Perfect Forward Secrecy: yes
+- FIPS 140-3 (2019): yes
+cipher suites:
+- TLS_AES_128_GCM_SHA256
+- TLS_AES_256_GCM_SHA384
+- TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
+- TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
+- TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
+- TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
+signature schemes:
+- ecdsa_sha256
+- ecdsa_sha384
+- ecdsa_sha512
+- rsa_pss_pss_sha256
+- rsa_pss_pss_sha384
+- rsa_pss_pss_sha512
+- rsa_pss_rsae_sha256
+- rsa_pss_rsae_sha384
+- rsa_pss_rsae_sha512
+- rsa_pkcs1_sha256
+- rsa_pkcs1_sha384
+- rsa_pkcs1_sha512
+curves:
+- secp256r1
+- secp384r1

tls/s2n_cipher_preferences.c

@@ -1556,6 +1556,21 @@ const struct s2n_cipher_preferences cipher_preferences_aws_crt_sdk_default = {
     .allow_chacha20_boosting = false,
 };
 
+struct s2n_cipher_suite *cipher_suites_aws_crt_sdk_2025[] = {
+    &s2n_tls13_aes_128_gcm_sha256,
+    &s2n_tls13_aes_256_gcm_sha384,
+    &s2n_ecdhe_ecdsa_with_aes_128_gcm_sha256,
+    &s2n_ecdhe_rsa_with_aes_128_gcm_sha256,
+    &s2n_ecdhe_ecdsa_with_aes_256_gcm_sha384,
+    &s2n_ecdhe_rsa_with_aes_256_gcm_sha384,
+};
+
+const struct s2n_cipher_preferences cipher_preferences_aws_crt_sdk_2025 = {
+    .count = s2n_array_len(cipher_suites_aws_crt_sdk_2025),
+    .suites = cipher_suites_aws_crt_sdk_2025,
+    .allow_chacha20_boosting = false,
+};
+
 struct s2n_cipher_suite *cipher_suites_aws_crt_sdk_tls_13[] = {
     S2N_TLS13_CLOUDFRONT_CIPHER_SUITES_20200716
 };

tls/s2n_cipher_preferences.h

@@ -117,6 +117,7 @@ extern const struct s2n_cipher_preferences cipher_preferences_cloudfront_tls_1_2
 extern const struct s2n_cipher_preferences cipher_preferences_aws_crt_sdk_ssl_v3;
 extern const struct s2n_cipher_preferences cipher_preferences_aws_crt_sdk_default;
 extern const struct s2n_cipher_preferences cipher_preferences_aws_crt_sdk_tls_13;
+extern const struct s2n_cipher_preferences cipher_preferences_aws_crt_sdk_2025;
 
 /* AWS KMS Cipher Preferences */
 extern const struct s2n_cipher_preferences cipher_preferences_kms_tls_1_0_2018_10;

tls/s2n_security_policies.c

@@ -557,6 +557,18 @@ const struct s2n_security_policy security_policy_aws_crt_sdk_tls_12_06_23 = {
     .ecc_preferences = &s2n_ecc_preferences_20230623,
 };
 
+const struct s2n_security_policy security_policy_aws_crt_sdk_tls_30_06_25 = {
+    .minimum_protocol_version = S2N_TLS12,
+    .cipher_preferences = &cipher_preferences_aws_crt_sdk_2025,
+    .kem_preferences = &kem_preferences_null,
+    .signature_preferences = &s2n_signature_preferences_20240501,
+    .ecc_preferences = &s2n_ecc_preferences_20140601,
+    .rules = {
+            [S2N_PERFECT_FORWARD_SECRECY] = true,
+            [S2N_FIPS_140_3] = true,
+    },
+};
+
 const struct s2n_security_policy security_policy_aws_crt_sdk_tls_13_06_23 = {
     .minimum_protocol_version = S2N_TLS13,
     .cipher_preferences = &cipher_preferences_aws_crt_sdk_tls_13,
@@ -1325,6 +1337,7 @@ struct s2n_security_policy_selection security_policy_selection[] = {
     { .version = "AWS-CRT-SDK-TLSv1.1-2023", .security_policy = &security_policy_aws_crt_sdk_tls_11_06_23, .ecc_extension_required = 0, .pq_kem_extension_required = 0 },
     { .version = "AWS-CRT-SDK-TLSv1.2-2023", .security_policy = &security_policy_aws_crt_sdk_tls_12_06_23, .ecc_extension_required = 0, .pq_kem_extension_required = 0 },
     { .version = "AWS-CRT-SDK-TLSv1.2-2023-PQ", .security_policy = &security_policy_aws_crt_sdk_tls_12_06_23_pq, .ecc_extension_required = 0, .pq_kem_extension_required = 0 },
+    { .version = "AWS-CRT-SDK-TLSv1.2-2025", .security_policy = &security_policy_aws_crt_sdk_tls_30_06_25, .ecc_extension_required = 0, .pq_kem_extension_required = 0 },
     { .version = "AWS-CRT-SDK-TLSv1.3-2023", .security_policy = &security_policy_aws_crt_sdk_tls_13_06_23, .ecc_extension_required = 0, .pq_kem_extension_required = 0 },
     /* KMS TLS Policies*/
     { .version = "KMS-TLS-1-0-2018-10", .security_policy = &security_policy_kms_tls_1_0_2018_10, .ecc_extension_required = 0, .pq_kem_extension_required = 0 },