commit 52bf54ecd4aa48a95f16c2e678ede7d24ef4d322 Author: David Goulet <dgoulet@torproject.org> Date: Tue May 28 12:35:04 2019 -0400 hs-v3: Add a series of decoding error code This commit introduces the hs_desc_decode_status_t enum which aims at having more fine grained error code when decoding a descriptor. This will be useful in later commits when we support keeping a descriptor that can't be decrypted due to missing or bad client authorization creds. No behavior change. Part of #30382. Signed-off-by: David Goulet <dgoulet@torproject.org> --- src/feature/hs/hs_client.c | 2 +- src/feature/hs/hs_descriptor.c | 71 ++++++++++++++++++++---------------------- src/feature/hs/hs_descriptor.h | 9 ++++++ src/test/test_hs_cache.c | 4 +-- src/test/test_hs_descriptor.c | 30 +++++++++--------- 5 files changed, 60 insertions(+), 56 deletions(-) diff --git a/src/feature/hs/hs_client.c b/src/feature/hs/hs_client.c index 4e2c520b9..4f6686143 100644 --- a/src/feature/hs/hs_client.c +++ b/src/feature/hs/hs_client.c @@ -1320,7 +1320,7 @@ hs_client_decode_descriptor(const char *desc_str, ret = hs_desc_decode_descriptor(desc_str, subcredential, client_auht_sk, desc); memwipe(subcredential, 0, sizeof(subcredential)); - if (ret < 0) { + if (ret != HS_DESC_DECODE_OK) { goto err; } diff --git a/src/feature/hs/hs_descriptor.c b/src/feature/hs/hs_descriptor.c index 60f2bfb0d..056dc81a6 100644 --- a/src/feature/hs/hs_descriptor.c +++ b/src/feature/hs/hs_descriptor.c @@ -2038,7 +2038,7 @@ desc_sig_is_valid(const char *b64_sig, * unknowns but requires that all v3 token be present and valid. * * Return 0 on success else a negative value. */ -static int +static hs_desc_decode_status_t desc_decode_plaintext_v3(smartlist_t *tokens, hs_desc_plaintext_data_t *desc, const char *encoded_desc, size_t encoded_len) @@ -2128,21 +2128,19 @@ desc_decode_plaintext_v3(smartlist_t *tokens, goto err; } - return 0; - + return HS_DESC_DECODE_OK; err: - return -1; + return HS_DESC_DECODE_PLAINTEXT_ERROR; } /** Decode the version 3 superencrypted section of the given descriptor desc. - * The desc_superencrypted_out will be populated with the decoded data. - * Return 0 on success else -1. */ -static int + * The desc_superencrypted_out will be populated with the decoded data. */ +static hs_desc_decode_status_t desc_decode_superencrypted_v3(const hs_descriptor_t *desc, hs_desc_superencrypted_data_t * desc_superencrypted_out) { - int ret = -1; + int ret = HS_DESC_DECODE_SUPERENC_ERROR; char *message = NULL; size_t message_len; memarea_t *area = NULL; @@ -2228,11 +2226,11 @@ desc_decode_superencrypted_v3(const hs_descriptor_t *desc, tok->object_size); superencrypted->encrypted_blob_size = tok->object_size; - ret = 0; + ret = HS_DESC_DECODE_OK; goto done; err: - tor_assert(ret < 0); + tor_assert(ret < HS_DESC_DECODE_OK); hs_desc_superencrypted_data_free_contents(desc_superencrypted_out); done: @@ -2250,14 +2248,13 @@ desc_decode_superencrypted_v3(const hs_descriptor_t *desc, } /** Decode the version 3 encrypted section of the given descriptor desc. The - * desc_encrypted_out will be populated with the decoded data. Return 0 on - * success else -1. */ -static int + * desc_encrypted_out will be populated with the decoded data. */ +static hs_desc_decode_status_t desc_decode_encrypted_v3(const hs_descriptor_t *desc, const curve25519_secret_key_t *client_auth_sk, hs_desc_encrypted_data_t *desc_encrypted_out) { - int ret = -1; + int ret = HS_DESC_DECODE_ENCRYPTED_ERROR; char *message = NULL; size_t message_len; memarea_t *area = NULL; @@ -2343,11 +2340,11 @@ desc_decode_encrypted_v3(const hs_descriptor_t *desc, /* NOTE: Unknown fields are allowed because this function could be used to * decode other descriptor version. */ - ret = 0; + ret = HS_DESC_DECODE_OK; goto done; err: - tor_assert(ret < 0); + tor_assert(ret < HS_DESC_DECODE_OK); hs_desc_encrypted_data_free_contents(desc_encrypted_out); done: @@ -2366,7 +2363,7 @@ desc_decode_encrypted_v3(const hs_descriptor_t *desc, /** Table of encrypted decode function version specific. The function are * indexed by the version number so v3 callback is at index 3 in the array. */ -static int +static hs_desc_decode_status_t (*decode_encrypted_handlers[])( const hs_descriptor_t *desc, const curve25519_secret_key_t *client_auth_sk, @@ -2379,12 +2376,12 @@ static int /** Decode the encrypted data section of the given descriptor and store the * data in the given encrypted data object. Return 0 on success else a * negative value on error. */ -int +hs_desc_decode_status_t hs_desc_decode_encrypted(const hs_descriptor_t *desc, const curve25519_secret_key_t *client_auth_sk, hs_desc_encrypted_data_t *desc_encrypted) { - int ret; + int ret = HS_DESC_DECODE_ENCRYPTED_ERROR; uint32_t version; tor_assert(desc); @@ -2398,7 +2395,6 @@ hs_desc_decode_encrypted(const hs_descriptor_t *desc, /* Let's make sure we have a supported version as well. By correctly parsing * the plaintext, this should not fail. */ if (BUG(!hs_desc_is_supported_version(version))) { - ret = -1; goto err; } /* Extra precaution. Having no handler for the supported version should @@ -2419,7 +2415,7 @@ hs_desc_decode_encrypted(const hs_descriptor_t *desc, /** Table of superencrypted decode function version specific. The function are * indexed by the version number so v3 callback is at index 3 in the array. */ -static int +static hs_desc_decode_status_t (*decode_superencrypted_handlers[])( const hs_descriptor_t *desc, hs_desc_superencrypted_data_t *desc_superencrypted) = @@ -2429,14 +2425,13 @@ static int }; /** Decode the superencrypted data section of the given descriptor and store - * the data in the given superencrypted data object. Return 0 on success else - * a negative value on error. */ -int + * the data in the given superencrypted data object. */ +hs_desc_decode_status_t hs_desc_decode_superencrypted(const hs_descriptor_t *desc, hs_desc_superencrypted_data_t * desc_superencrypted) { - int ret; + int ret = HS_DESC_DECODE_SUPERENC_ERROR; uint32_t version; tor_assert(desc); @@ -2450,7 +2445,6 @@ hs_desc_decode_superencrypted(const hs_descriptor_t *desc, /* Let's make sure we have a supported version as well. By correctly parsing * the plaintext, this should not fail. */ if (BUG(!hs_desc_is_supported_version(version))) { - ret = -1; goto err; } /* Extra precaution. Having no handler for the supported version should @@ -2470,7 +2464,7 @@ hs_desc_decode_superencrypted(const hs_descriptor_t *desc, /** Table of plaintext decode function version specific. The function are * indexed by the version number so v3 callback is at index 3 in the array. */ -static int +static hs_desc_decode_status_t (*decode_plaintext_handlers[])( smartlist_t *tokens, hs_desc_plaintext_data_t *desc, @@ -2482,12 +2476,12 @@ static int }; /** Fully decode the given descriptor plaintext and store the data in the - * plaintext data object. Returns 0 on success else a negative value. */ -int + * plaintext data object. */ +hs_desc_decode_status_t hs_desc_decode_plaintext(const char *encoded, hs_desc_plaintext_data_t *plaintext) { - int ok = 0, ret = -1; + int ok = 0, ret = HS_DESC_DECODE_PLAINTEXT_ERROR; memarea_t *area = NULL; smartlist_t *tokens = NULL; size_t encoded_len; @@ -2537,11 +2531,11 @@ hs_desc_decode_plaintext(const char *encoded, /* Run the version specific plaintext decoder. */ ret = decode_plaintext_handlers[plaintext->version](tokens, plaintext, encoded, encoded_len); - if (ret < 0) { + if (ret != HS_DESC_DECODE_OK) { goto err; } /* Success. Descriptor has been populated with the data. */ - ret = 0; + ret = HS_DESC_DECODE_OK; err: if (tokens) { @@ -2560,13 +2554,13 @@ hs_desc_decode_plaintext(const char *encoded, * * Return 0 on success. A negative value is returned on error and desc_out is * set to NULL. */ -int +hs_desc_decode_status_t hs_desc_decode_descriptor(const char *encoded, const uint8_t *subcredential, const curve25519_secret_key_t *client_auth_sk, hs_descriptor_t **desc_out) { - int ret = -1; + hs_desc_decode_status_t ret = HS_DESC_DECODE_GENERIC_ERROR; hs_descriptor_t *desc; tor_assert(encoded); @@ -2583,17 +2577,17 @@ hs_desc_decode_descriptor(const char *encoded, memcpy(desc->subcredential, subcredential, sizeof(desc->subcredential)); ret = hs_desc_decode_plaintext(encoded, &desc->plaintext_data); - if (ret < 0) { + if (ret != HS_DESC_DECODE_OK) { goto err; } ret = hs_desc_decode_superencrypted(desc, &desc->superencrypted_data); - if (ret < 0) { + if (ret != HS_DESC_DECODE_OK) { goto err; } ret = hs_desc_decode_encrypted(desc, client_auth_sk, &desc->encrypted_data); - if (ret < 0) { + if (ret != HS_DESC_DECODE_OK) { goto err; } @@ -2672,7 +2666,8 @@ hs_desc_encode_descriptor,(const hs_descriptor_t *desc, if (!descriptor_cookie) { ret = hs_desc_decode_descriptor(*encoded_out, desc->subcredential, NULL, NULL); - if (BUG(ret < 0)) { + if (BUG(ret != HS_DESC_DECODE_OK)) { + ret = -1; goto err; } } diff --git a/src/feature/hs/hs_descriptor.h b/src/feature/hs/hs_descriptor.h index 731e0c5ce..8d9dac174 100644 --- a/src/feature/hs/hs_descriptor.h +++ b/src/feature/hs/hs_descriptor.h @@ -69,6 +69,15 @@ typedef enum { HS_DESC_AUTH_ED25519 = 1 } hs_desc_auth_type_t; +/** Error code when decoding a descriptor. */ +typedef enum { + HS_DESC_DECODE_ENCRYPTED_ERROR = -4, + HS_DESC_DECODE_SUPERENC_ERROR = -3, + HS_DESC_DECODE_PLAINTEXT_ERROR = -2, + HS_DESC_DECODE_GENERIC_ERROR = -1, + HS_DESC_DECODE_OK = 0, +} hs_desc_decode_status_t; + /** Introduction point information located in a descriptor. */ typedef struct hs_desc_intro_point_t { /** Link specifier(s) which details how to extend to the relay. This list diff --git a/src/test/test_hs_cache.c b/src/test/test_hs_cache.c index 86ac7e7fb..88cd4079e 100644 --- a/src/test/test_hs_cache.c +++ b/src/test/test_hs_cache.c @@ -411,7 +411,7 @@ test_hsdir_revision_counter_check(void *arg) retval = hs_desc_decode_descriptor(received_desc_str, subcredential, NULL, &received_desc); - tt_int_op(retval, OP_EQ, 0); + tt_int_op(retval, OP_EQ, HS_DESC_DECODE_OK); tt_assert(received_desc); /* Check that the revision counter is correct */ @@ -444,7 +444,7 @@ test_hsdir_revision_counter_check(void *arg) retval = hs_desc_decode_descriptor(received_desc_str, subcredential, NULL, &received_desc); - tt_int_op(retval, OP_EQ, 0); + tt_int_op(retval, OP_EQ, HS_DESC_DECODE_OK); tt_assert(received_desc); /* Check that the revision counter is the latest */ diff --git a/src/test/test_hs_descriptor.c b/src/test/test_hs_descriptor.c index 6fe5573c0..3d6d8e67d 100644 --- a/src/test/test_hs_descriptor.c +++ b/src/test/test_hs_descriptor.c @@ -235,14 +235,14 @@ test_decode_descriptor(void *arg) /* Give some bad stuff to the decoding function. */ ret = hs_desc_decode_descriptor("hladfjlkjadf", subcredential, NULL, &decoded); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); ret = hs_desc_encode_descriptor(desc, &signing_kp, NULL, &encoded); - tt_int_op(ret, OP_EQ, 0); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_OK); tt_assert(encoded); ret = hs_desc_decode_descriptor(encoded, subcredential, NULL, &decoded); - tt_int_op(ret, OP_EQ, 0); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_OK); tt_assert(decoded); hs_helper_desc_equal(desc, decoded); @@ -263,7 +263,7 @@ test_decode_descriptor(void *arg) tt_assert(encoded); hs_descriptor_free(decoded); ret = hs_desc_decode_descriptor(encoded, subcredential, NULL, &decoded); - tt_int_op(ret, OP_EQ, 0); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_OK); tt_assert(decoded); } @@ -317,21 +317,21 @@ test_decode_descriptor(void *arg) hs_descriptor_free(decoded); ret = hs_desc_decode_descriptor(encoded, subcredential, NULL, &decoded); - tt_int_op(ret, OP_LT, 0); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_ENCRYPTED_ERROR); tt_assert(!decoded); /* If we have an invalid client secret key, the decoding must fail. */ hs_descriptor_free(decoded); ret = hs_desc_decode_descriptor(encoded, subcredential, &invalid_client_kp.seckey, &decoded); - tt_int_op(ret, OP_LT, 0); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_ENCRYPTED_ERROR); tt_assert(!decoded); /* If we have the client secret key, the decoding must succeed and the * decoded descriptor must be correct. */ ret = hs_desc_decode_descriptor(encoded, subcredential, &client_kp.seckey, &decoded); - tt_int_op(ret, OP_EQ, 0); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_OK); tt_assert(decoded); hs_helper_desc_equal(desc, decoded); @@ -567,7 +567,7 @@ test_decode_bad_signature(void *arg) setup_full_capture_of_logs(LOG_WARN); ret = hs_desc_decode_plaintext(HS_DESC_BAD_SIG, &desc_plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); expect_log_msg_containing("Malformed signature line. Rejecting."); teardown_capture_of_logs(); @@ -607,14 +607,14 @@ test_decode_plaintext(void *arg) tor_asprintf(&plaintext, template, bad_value, "180", "42", "MESSAGE"); ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); tor_free(plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } /* Missing fields. */ { const char *plaintext = "hs-descriptor 3\n"; ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } /* Max length. */ @@ -627,7 +627,7 @@ test_decode_plaintext(void *arg) plaintext[big - 1] = '\0'; ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); tor_free(plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } /* Bad lifetime value. */ @@ -636,7 +636,7 @@ test_decode_plaintext(void *arg) tor_asprintf(&plaintext, template, "3", bad_value, "42", "MESSAGE"); ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); tor_free(plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } /* Huge lifetime value. */ @@ -645,7 +645,7 @@ test_decode_plaintext(void *arg) tor_asprintf(&plaintext, template, "3", "7181615", "42", "MESSAGE"); ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); tor_free(plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } /* Invalid encrypted section. */ @@ -654,7 +654,7 @@ test_decode_plaintext(void *arg) tor_asprintf(&plaintext, template, "3", "180", "42", bad_value); ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); tor_free(plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } /* Invalid revision counter. */ @@ -663,7 +663,7 @@ test_decode_plaintext(void *arg) tor_asprintf(&plaintext, template, "3", "180", bad_value, "MESSAGE"); ret = hs_desc_decode_plaintext(plaintext, &desc_plaintext); tor_free(plaintext); - tt_int_op(ret, OP_EQ, -1); + tt_int_op(ret, OP_EQ, HS_DESC_DECODE_PLAINTEXT_ERROR); } done: