From 67c55d5869d5473e5139614637f31ea37746181d Mon Sep 17 00:00:00 2001 From: Dimitri Staessens Date: Thu, 11 Jun 2026 10:03:14 +0000 Subject: irmd: Specify peer authentication contract OAP accepted requests and responses without a certificate even when the peer was expected to authenticate. An on-path attacker could strip the certificate and signature from a flow allocation response and substitute its own key exchange, silently downgrading the handshake to unauthenticated. Add an auth=required|optional policy to enc.conf, enforced per role: a client config requires the server to present a valid certificate, a server config requires the same from the client. Default is required for client side (https), optional server side. The client side default can be changed via OAP_CLIENT_AUTH_DEFAULT for testing. Replace the bare 'none' keyword with encryption=none, which disables encryption only: the digest and the authentication policy are kept, so authenticated but unencrypted flows can be configured. Configs using bare 'none' are now rejected. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders --- src/lib/crypt.c | 31 +++++- src/lib/tests/kex_test.c | 273 ++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 294 insertions(+), 10 deletions(-) (limited to 'src/lib') diff --git a/src/lib/crypt.c b/src/lib/crypt.c index 71197f6e..66d07131 100644 --- a/src/lib/crypt.c +++ b/src/lib/crypt.c @@ -162,6 +162,7 @@ int parse_sec_config(struct sec_config * cfg, char * equals; char * key; char * value; + bool no_enc = false; assert(cfg != NULL); assert(fp != NULL); @@ -172,6 +173,7 @@ int parse_sec_config(struct sec_config * cfg, SET_KEX_KDF_NID(cfg, NID_sha256); SET_KEX_CIPHER_NID(cfg, NID_aes_256_gcm); SET_KEX_DIGEST_NID(cfg, NID_sha256); + /* req_auth is seeded per-role by the caller; only auth= overrides it */ while (fgets(line, sizeof(line), fp) != NULL) { char * trimmed; @@ -180,12 +182,10 @@ int parse_sec_config(struct sec_config * cfg, if (line[0] == '#' || line[0] == '\n') continue; - /* Check for 'none' keyword */ + /* Bare 'none' keyword replaced by encryption=none */ trimmed = trim_whitespace(line); - if (strcmp(trimmed, "none") == 0) { - memset(cfg, 0, sizeof(*cfg)); - return 0; - } + if (strcmp(trimmed, "none") == 0) + return -EINVAL; /* Find the = separator */ equals = strchr(line, '='); @@ -221,9 +221,30 @@ int parse_sec_config(struct sec_config * cfg, } else { return -EINVAL; } + } else if (strcmp(key, "auth") == 0) { + if (strcmp(value, "required") == 0) { + cfg->req_auth = true; + } else if (strcmp(value, "optional") == 0) { + cfg->req_auth = false; + } else { + return -EINVAL; + } + } else if (strcmp(key, "encryption") == 0) { + if (strcmp(value, "none") != 0) + return -EINVAL; + no_enc = true; + } else { + return -EINVAL; } } + if (no_enc) { + /* Digest stays: it belongs to the auth axis */ + CLEAR_KEX_ALGO(cfg); + CLEAR_KEX_KDF(cfg); + CLEAR_KEX_CIPHER(cfg); + } + return 0; } diff --git a/src/lib/tests/kex_test.c b/src/lib/tests/kex_test.c index 6a4f802e..300a0607 100644 --- a/src/lib/tests/kex_test.c +++ b/src/lib/tests/kex_test.c @@ -44,6 +44,9 @@ #define KEX_CONFIG_NONE \ "none\n" +#define KEX_CONFIG_NO_ENC \ + "encryption=none\n" + #define KEX_CONFIG_WHITESPACE \ "# Comment line\n" \ "kex = X448" \ @@ -58,6 +61,25 @@ "kex=X25519\n" \ "digest=sha384\n" +#define KEX_CONFIG_AUTH \ + "auth=required\n" + +#define KEX_CONFIG_AUTH_INVALID \ + "auth=mandatory\n" + +#define KEX_CONFIG_AUTH_OPTIONAL \ + "auth=optional\n" + +#define KEX_CONFIG_AUTH_THEN_NO_ENC \ + "auth=required\n" \ + "digest=sha512\n" \ + "encryption=none\n" + +#define KEX_CONFIG_NO_ENC_THEN_AUTH \ + "encryption=none\n" \ + "auth=required\n" \ + "digest=sha512\n" + /* Test key material for key loading tests */ #define X25519_PRIVKEY_PEM \ "-----BEGIN PRIVATE KEY-----\n" \ @@ -639,7 +661,8 @@ static int test_kex_parse_config_custom(void) return TEST_RC_FAIL; } -static int test_kex_parse_config_none(void) +/* The old bare 'none' keyword must be rejected loudly */ +static int test_kex_parse_config_none_rejected(void) { struct sec_config kex; FILE * fp; @@ -654,14 +677,51 @@ static int test_kex_parse_config_none(void) goto fail; } + if (parse_sec_config(&kex, fp) == 0) { + printf("Bare 'none' keyword should be rejected.\n"); + fclose(fp); + goto fail; + } + + fclose(fp); + + TEST_SUCCESS(); + + return TEST_RC_SUCCESS; + fail: + TEST_FAIL(); + return TEST_RC_FAIL; +} + +static int test_kex_parse_config_no_enc(void) +{ + struct sec_config kex; + FILE * fp; + + TEST_START(); + + memset(&kex, 0, sizeof(kex)); + + fp = FMEMOPEN_STR(KEX_CONFIG_NO_ENC); + if (fp == NULL) { + printf("Failed to open memory stream.\n"); + goto fail; + } + if (parse_sec_config(&kex, fp) < 0) { - printf("Failed to parse 'none' config.\n"); + printf("Failed to parse encryption=none config.\n"); fclose(fp); goto fail; } - if (kex.x.nid != NID_undef) { - printf("'none' keyword should disable encryption.\n"); + if (kex.x.nid != NID_undef || kex.c.nid != NID_undef) { + printf("encryption=none should disable encryption.\n"); + fclose(fp); + goto fail; + } + + if (kex.d.nid != NID_sha256) { + printf("encryption=none should keep the digest.\n"); fclose(fp); goto fail; } @@ -799,6 +859,202 @@ static int test_kex_parse_config_digest(void) return TEST_RC_FAIL; } +static int test_kex_parse_config_auth(void) +{ + struct sec_config kex; + FILE * fp; + + TEST_START(); + + memset(&kex, 0, sizeof(kex)); + + fp = FMEMOPEN_STR(KEX_CONFIG_AUTH); + if (fp == NULL) { + printf("Failed to open memory stream.\n"); + goto fail; + } + + if (parse_sec_config(&kex, fp) < 0) { + printf("Failed to parse auth config.\n"); + fclose(fp); + goto fail; + } + + if (!kex.req_auth) { + printf("auth=required not parsed correctly.\n"); + fclose(fp); + goto fail; + } + + fclose(fp); + + TEST_SUCCESS(); + + return TEST_RC_SUCCESS; + fail: + TEST_FAIL(); + return TEST_RC_FAIL; +} + +static int test_kex_parse_config_auth_invalid(void) +{ + struct sec_config kex; + FILE * fp; + + TEST_START(); + + memset(&kex, 0, sizeof(kex)); + + fp = FMEMOPEN_STR(KEX_CONFIG_AUTH_INVALID); + if (fp == NULL) { + printf("Failed to open memory stream.\n"); + goto fail; + } + + if (parse_sec_config(&kex, fp) == 0) { + printf("Invalid auth value should be rejected.\n"); + fclose(fp); + goto fail; + } + + fclose(fp); + + TEST_SUCCESS(); + + return TEST_RC_SUCCESS; + fail: + TEST_FAIL(); + return TEST_RC_FAIL; +} + +/* A caller-seeded req_auth survives parsing when no auth= line is set */ +static int test_kex_parse_config_auth_seed(void) +{ + struct sec_config kex; + FILE * fp; + + TEST_START(); + + memset(&kex, 0, sizeof(kex)); + kex.req_auth = true; + + fp = FMEMOPEN_STR(KEX_CONFIG_NO_ENC); + if (fp == NULL) { + printf("Failed to open memory stream.\n"); + goto fail; + } + + if (parse_sec_config(&kex, fp) < 0) { + printf("Failed to parse config.\n"); + fclose(fp); + goto fail; + } + + if (!kex.req_auth) { + printf("Seeded req_auth should survive parsing.\n"); + fclose(fp); + goto fail; + } + + fclose(fp); + + TEST_SUCCESS(); + + return TEST_RC_SUCCESS; + fail: + TEST_FAIL(); + return TEST_RC_FAIL; +} + +/* An explicit auth=optional clears a caller-seeded req_auth */ +static int test_kex_parse_config_auth_optional(void) +{ + struct sec_config kex; + FILE * fp; + + TEST_START(); + + memset(&kex, 0, sizeof(kex)); + kex.req_auth = true; + + fp = FMEMOPEN_STR(KEX_CONFIG_AUTH_OPTIONAL); + if (fp == NULL) { + printf("Failed to open memory stream.\n"); + goto fail; + } + + if (parse_sec_config(&kex, fp) < 0) { + printf("Failed to parse auth=optional config.\n"); + fclose(fp); + goto fail; + } + + if (kex.req_auth) { + printf("auth=optional should clear req_auth.\n"); + fclose(fp); + goto fail; + } + + fclose(fp); + + TEST_SUCCESS(); + + return TEST_RC_SUCCESS; + fail: + TEST_FAIL(); + return TEST_RC_FAIL; +} + +/* encryption=none must not drop auth=required or the digest */ +static int test_kex_parse_config_auth_no_enc(const char * config) +{ + struct sec_config kex; + FILE * fp; + + TEST_START(); + + memset(&kex, 0, sizeof(kex)); + + fp = FMEMOPEN_STR(config); + if (fp == NULL) { + printf("Failed to open memory stream.\n"); + goto fail; + } + + if (parse_sec_config(&kex, fp) < 0) { + printf("Failed to parse auth + encryption=none.\n"); + fclose(fp); + goto fail; + } + + if (!kex.req_auth) { + printf("encryption=none should not drop required auth.\n"); + fclose(fp); + goto fail; + } + + if (kex.x.nid != NID_undef) { + printf("encryption=none should disable encryption.\n"); + fclose(fp); + goto fail; + } + + if (kex.d.nid != NID_sha512) { + printf("encryption=none should keep the digest.\n"); + fclose(fp); + goto fail; + } + + fclose(fp); + + TEST_SUCCESS(); + + return TEST_RC_SUCCESS; + fail: + TEST_FAIL(); + return TEST_RC_FAIL; +} + int kex_test(int argc, char ** argv) { @@ -809,7 +1065,14 @@ int kex_test(int argc, ret |= test_kex_create_destroy(); ret |= test_kex_parse_config_empty(); - ret |= test_kex_parse_config_none(); + ret |= test_kex_parse_config_none_rejected(); + ret |= test_kex_parse_config_no_enc(); + ret |= test_kex_parse_config_auth(); + ret |= test_kex_parse_config_auth_invalid(); + ret |= test_kex_parse_config_auth_seed(); + ret |= test_kex_parse_config_auth_optional(); + ret |= test_kex_parse_config_auth_no_enc(KEX_CONFIG_AUTH_THEN_NO_ENC); + ret |= test_kex_parse_config_auth_no_enc(KEX_CONFIG_NO_ENC_THEN_AUTH); #ifdef HAVE_OPENSSL ret |= test_kex_parse_config_custom(); ret |= test_kex_parse_config_whitespace(); -- cgit v1.2.3