diff options
Diffstat (limited to 'src/or/hs_descriptor.c')
| -rw-r--r-- | src/or/hs_descriptor.c | 252 |
1 files changed, 222 insertions, 30 deletions
diff --git a/src/or/hs_descriptor.c b/src/or/hs_descriptor.c index 2393eac252..9a1e377155 100644 --- a/src/or/hs_descriptor.c +++ b/src/or/hs_descriptor.c @@ -58,6 +58,7 @@ #include "hs_descriptor.h" #include "or.h" +#include "circuitbuild.h" #include "ed25519_cert.h" /* Trunnel interface. */ #include "parsecommon.h" #include "rendcache.h" @@ -78,6 +79,7 @@ #define str_intro_auth_required "intro-auth-required" #define str_single_onion "single-onion-service" #define str_intro_point "introduction-point" +#define str_ip_onion_key "onion-key" #define str_ip_auth_key "auth-key" #define str_ip_enc_key "enc-key" #define str_ip_enc_key_cert "enc-key-cert" @@ -136,6 +138,7 @@ static token_rule_t hs_desc_encrypted_v3_token_table[] = { /* Descriptor ruleset for the introduction points section. */ static token_rule_t hs_desc_intro_point_v3_token_table[] = { T1_START(str_intro_point, R3_INTRODUCTION_POINT, EQ(1), NO_OBJ), + T1N(str_ip_onion_key, R3_INTRO_ONION_KEY, GE(2), OBJ_OK), T1(str_ip_auth_key, R3_INTRO_AUTH_KEY, NO_ARGS, NEED_OBJ), T1(str_ip_enc_key, R3_INTRO_ENC_KEY, GE(2), OBJ_OK), T1(str_ip_enc_key_cert, R3_INTRO_ENC_KEY_CERT, ARGS, OBJ_OK), @@ -144,29 +147,6 @@ static token_rule_t hs_desc_intro_point_v3_token_table[] = { END_OF_TABLE }; -/* Free a descriptor intro point object. */ -STATIC void -desc_intro_point_free(hs_desc_intro_point_t *ip) -{ - if (!ip) { - return; - } - if (ip->link_specifiers) { - SMARTLIST_FOREACH(ip->link_specifiers, hs_desc_link_specifier_t *, - ls, tor_free(ls)); - smartlist_free(ip->link_specifiers); - } - tor_cert_free(ip->auth_key_cert); - tor_cert_free(ip->enc_key_cert); - if (ip->legacy.key) { - crypto_pk_free(ip->legacy.key); - } - if (ip->legacy.cert.encoded) { - tor_free(ip->legacy.cert.encoded); - } - tor_free(ip); -} - /* Free the content of the plaintext section of a descriptor. */ static void desc_plaintext_data_free_contents(hs_desc_plaintext_data_t *desc) @@ -197,7 +177,7 @@ desc_encrypted_data_free_contents(hs_desc_encrypted_data_t *desc) } if (desc->intro_points) { SMARTLIST_FOREACH(desc->intro_points, hs_desc_intro_point_t *, ip, - desc_intro_point_free(ip)); + hs_desc_intro_point_free(ip)); smartlist_free(desc->intro_points); } memwipe(desc, 0, sizeof(*desc)); @@ -256,7 +236,7 @@ build_secret_input(const hs_descriptor_t *desc, uint8_t *dst, size_t dstlen) memcpy(dst + offset, desc->subcredential, sizeof(desc->subcredential)); offset += sizeof(desc->subcredential); /* Copy revision counter value. */ - set_uint64(dst + offset, tor_ntohll(desc->plaintext_data.revision_counter)); + set_uint64(dst + offset, tor_htonll(desc->plaintext_data.revision_counter)); offset += sizeof(uint64_t); tor_assert(HS_DESC_ENCRYPTED_SECRET_INPUT_LEN == offset); } @@ -383,6 +363,14 @@ encode_link_specifiers(const smartlist_t *specs) link_specifier_set_ls_len(ls, legacy_id_len); break; } + case LS_ED25519_ID: + { + size_t ed25519_id_len = link_specifier_getlen_un_ed25519_id(ls); + uint8_t *ed25519_id_array = link_specifier_getarray_un_ed25519_id(ls); + memcpy(ed25519_id_array, spec->u.ed25519_id, ed25519_id_len); + link_specifier_set_ls_len(ls, ed25519_id_len); + break; + } default: tor_assert(0); } @@ -479,6 +467,26 @@ encode_enc_key(const hs_desc_intro_point_t *ip) return encoded; } +/* Encode an introduction point onion key. Return a newly allocated string + * with it. On failure, return NULL. */ +static char * +encode_onion_key(const hs_desc_intro_point_t *ip) +{ + char *encoded = NULL; + char key_b64[CURVE25519_BASE64_PADDED_LEN + 1]; + + tor_assert(ip); + + /* Base64 encode the encryption key for the "onion-key" field. */ + if (curve25519_public_to_base64(key_b64, &ip->onion_key) < 0) { + goto done; + } + tor_asprintf(&encoded, "%s ntor %s", str_ip_onion_key, key_b64); + + done: + return encoded; +} + /* Encode an introduction point object and return a newly allocated string * with it. On failure, return NULL. */ static char * @@ -498,6 +506,16 @@ encode_intro_point(const ed25519_public_key_t *sig_key, tor_free(ls_str); } + /* Onion key encoding. */ + { + char *encoded_onion_key = encode_onion_key(ip); + if (encoded_onion_key == NULL) { + goto err; + } + smartlist_add_asprintf(lines, "%s", encoded_onion_key); + tor_free(encoded_onion_key); + } + /* Authentication key encoding. */ { char *encoded_cert; @@ -988,6 +1006,10 @@ desc_encode_v3(const hs_descriptor_t *desc, tor_assert(encoded_out); tor_assert(desc->plaintext_data.version == 3); + if (BUG(desc->subcredential == NULL)) { + goto err; + } + /* Build the non-encrypted values. */ { char *encoded_cert; @@ -1134,6 +1156,15 @@ decode_link_specifiers(const char *encoded) memcpy(hs_spec->u.legacy_id, link_specifier_getarray_un_legacy_id(ls), sizeof(hs_spec->u.legacy_id)); break; + case LS_ED25519_ID: + /* Both are known at compile time so let's make sure they are the same + * else we can copy memory out of bound. */ + tor_assert(link_specifier_getlen_un_ed25519_id(ls) == + sizeof(hs_spec->u.ed25519_id)); + memcpy(hs_spec->u.ed25519_id, + link_specifier_getconstarray_un_ed25519_id(ls), + sizeof(hs_spec->u.ed25519_id)); + break; default: goto err; } @@ -1626,6 +1657,50 @@ decode_intro_legacy_key(const directory_token_t *tok, return -1; } +/* Dig into the descriptor <b>tokens</b> to find the onion key we should use + * for this intro point, and set it into <b>onion_key_out</b>. Return 0 if it + * was found and well-formed, otherwise return -1 in case of errors. */ +static int +set_intro_point_onion_key(curve25519_public_key_t *onion_key_out, + const smartlist_t *tokens) +{ + int retval = -1; + smartlist_t *onion_keys = NULL; + + tor_assert(onion_key_out); + + onion_keys = find_all_by_keyword(tokens, R3_INTRO_ONION_KEY); + if (!onion_keys) { + log_warn(LD_REND, "Descriptor did not contain intro onion keys"); + goto err; + } + + SMARTLIST_FOREACH_BEGIN(onion_keys, directory_token_t *, tok) { + /* This field is using GE(2) so for possible forward compatibility, we + * accept more fields but must be at least 2. */ + tor_assert(tok->n_args >= 2); + + /* Try to find an ntor key, it's the only recognized type right now */ + if (!strcmp(tok->args[0], "ntor")) { + if (curve25519_public_from_base64(onion_key_out, tok->args[1]) < 0) { + log_warn(LD_REND, "Introduction point ntor onion-key is invalid"); + goto err; + } + /* Got the onion key! Set the appropriate retval */ + retval = 0; + } + } SMARTLIST_FOREACH_END(tok); + + /* Log an error if we didn't find it :( */ + if (retval < 0) { + log_warn(LD_REND, "Descriptor did not contain ntor onion keys"); + } + + err: + smartlist_free(onion_keys); + return retval; +} + /* Given the start of a section and the end of it, decode a single * introduction point from that section. Return a newly allocated introduction * point object containing the decoded data. Return NULL if the section can't @@ -1651,17 +1726,24 @@ decode_introduction_point(const hs_descriptor_t *desc, const char *start) /* Ok we seem to have a well formed section containing enough tokens to * parse. Allocate our IP object and try to populate it. */ - ip = tor_malloc_zero(sizeof(hs_desc_intro_point_t)); + ip = hs_desc_intro_point_new(); /* "introduction-point" SP link-specifiers NL */ tok = find_by_keyword(tokens, R3_INTRODUCTION_POINT); tor_assert(tok->n_args == 1); + /* Our constructor creates this list by default so free it. */ + smartlist_free(ip->link_specifiers); ip->link_specifiers = decode_link_specifiers(tok->args[0]); if (!ip->link_specifiers) { log_warn(LD_REND, "Introduction point has invalid link specifiers"); goto err; } + /* "onion-key" SP ntor SP key NL */ + if (set_intro_point_onion_key(&ip->onion_key, tokens) < 0) { + goto err; + } + /* "auth-key" NL certificate NL */ tok = find_by_keyword(tokens, R3_INTRO_AUTH_KEY); tor_assert(tok->object_body); @@ -1733,7 +1815,7 @@ decode_introduction_point(const hs_descriptor_t *desc, const char *start) goto done; err: - desc_intro_point_free(ip); + hs_desc_intro_point_free(ip); ip = NULL; done: @@ -2215,7 +2297,7 @@ hs_desc_decode_descriptor(const char *encoded, const uint8_t *subcredential, hs_descriptor_t **desc_out) { - int ret; + int ret = -1; hs_descriptor_t *desc; tor_assert(encoded); @@ -2223,10 +2305,13 @@ hs_desc_decode_descriptor(const char *encoded, desc = tor_malloc_zero(sizeof(hs_descriptor_t)); /* Subcredentials are optional. */ - if (subcredential) { - memcpy(desc->subcredential, subcredential, sizeof(desc->subcredential)); + if (BUG(!subcredential)) { + log_warn(LD_GENERAL, "Tried to decrypt without subcred. Impossible!"); + goto err; } + memcpy(desc->subcredential, subcredential, sizeof(desc->subcredential)); + ret = hs_desc_decode_plaintext(encoded, &desc->plaintext_data); if (ret < 0) { goto err; @@ -2352,3 +2437,110 @@ hs_desc_plaintext_obj_size(const hs_desc_plaintext_data_t *data) data->superencrypted_blob_size); } +/* Return a newly allocated descriptor intro point. */ +hs_desc_intro_point_t * +hs_desc_intro_point_new(void) +{ + hs_desc_intro_point_t *ip = tor_malloc_zero(sizeof(*ip)); + ip->link_specifiers = smartlist_new(); + return ip; +} + +/* Free a descriptor intro point object. */ +void +hs_desc_intro_point_free(hs_desc_intro_point_t *ip) +{ + if (ip == NULL) { + return; + } + if (ip->link_specifiers) { + SMARTLIST_FOREACH(ip->link_specifiers, hs_desc_link_specifier_t *, + ls, hs_desc_link_specifier_free(ls)); + smartlist_free(ip->link_specifiers); + } + tor_cert_free(ip->auth_key_cert); + tor_cert_free(ip->enc_key_cert); + crypto_pk_free(ip->legacy.key); + tor_free(ip->legacy.cert.encoded); + tor_free(ip); +} + +/* Free the given descriptor link specifier. */ +void +hs_desc_link_specifier_free(hs_desc_link_specifier_t *ls) +{ + if (ls == NULL) { + return; + } + tor_free(ls); +} + +/* Return a newly allocated descriptor link specifier using the given extend + * info and requested type. Return NULL on error. */ +hs_desc_link_specifier_t * +hs_desc_link_specifier_new(const extend_info_t *info, uint8_t type) +{ + hs_desc_link_specifier_t *ls = NULL; + + tor_assert(info); + + ls = tor_malloc_zero(sizeof(*ls)); + ls->type = type; + switch (ls->type) { + case LS_IPV4: + if (info->addr.family != AF_INET) { + goto err; + } + tor_addr_copy(&ls->u.ap.addr, &info->addr); + ls->u.ap.port = info->port; + break; + case LS_IPV6: + if (info->addr.family != AF_INET6) { + goto err; + } + tor_addr_copy(&ls->u.ap.addr, &info->addr); + ls->u.ap.port = info->port; + break; + case LS_LEGACY_ID: + /* Bug out if the identity digest is not set */ + if (BUG(tor_mem_is_zero(info->identity_digest, + sizeof(info->identity_digest)))) { + goto err; + } + memcpy(ls->u.legacy_id, info->identity_digest, sizeof(ls->u.legacy_id)); + break; + case LS_ED25519_ID: + /* ed25519 keys are optional for intro points */ + if (ed25519_public_key_is_zero(&info->ed_identity)) { + goto err; + } + memcpy(ls->u.ed25519_id, info->ed_identity.pubkey, + sizeof(ls->u.ed25519_id)); + break; + default: + /* Unknown type is code flow error. */ + tor_assert(0); + } + + return ls; + err: + tor_free(ls); + return NULL; +} + +/* From the given descriptor, remove and free every introduction point. */ +void +hs_descriptor_clear_intro_points(hs_descriptor_t *desc) +{ + smartlist_t *ips; + + tor_assert(desc); + + ips = desc->encrypted_data.intro_points; + if (ips) { + SMARTLIST_FOREACH(ips, hs_desc_intro_point_t *, + ip, hs_desc_intro_point_free(ip)); + smartlist_clear(ips); + } +} + |