/* This file is part of GNUnet Copyright (C) 2012, 2013 GNUnet e.V. GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /** * @author Christian Grothoff * * @file * API that can be used to manipulate GNS record data * * @defgroup gnsrecord GNS Record library * Manipulate GNS record data * * @see [Documentation](https://gnunet.org/gns-plugins) * * @{ */ #ifndef GNUNET_GNSRECORD_LIB_H #define GNUNET_GNSRECORD_LIB_H #ifdef __cplusplus extern "C" { #if 0 /* keep Emacsens' auto-indent happy */ } #endif #endif /** * Maximum size of a value that can be stored in a GNS block. */ #define GNUNET_GNSRECORD_MAX_BLOCK_SIZE (63 * 1024) /** * Record type indicating any record/'*' */ #define GNUNET_GNSRECORD_TYPE_ANY 0 /** * Record type for GNS zone transfer ("PKEY"). */ #define GNUNET_GNSRECORD_TYPE_PKEY 65536 /** * Record type for GNS nick names ("NICK"). */ #define GNUNET_GNSRECORD_TYPE_NICK 65537 /** * Record type for GNS legacy hostnames ("LEHO"). */ #define GNUNET_GNSRECORD_TYPE_LEHO 65538 /** * Record type for VPN resolution */ #define GNUNET_GNSRECORD_TYPE_VPN 65539 /** * Record type for delegation to DNS. */ #define GNUNET_GNSRECORD_TYPE_GNS2DNS 65540 /** * Record type for a boxed record (see TLSA/SRV handling in GNS). */ #define GNUNET_GNSRECORD_TYPE_BOX 65541 /** * Record type for a social place. */ #define GNUNET_GNSRECORD_TYPE_PLACE 65542 /** * Record type for a phone (of CONVERSATION). */ #define GNUNET_GNSRECORD_TYPE_PHONE 65543 /** * Record type for identity attributes (of IDENTITY). */ #define GNUNET_GNSRECORD_TYPE_ID_ATTR 65544 /** * Record type for an identity token (of IDENTITY-TOKEN). */ #define GNUNET_GNSRECORD_TYPE_ID_TOKEN 65545 /** * Record type for the private metadata of an identity token (of IDENTITY-TOKEN). */ #define GNUNET_GNSRECORD_TYPE_ID_TOKEN_METADATA 65546 /** * Record type for credential */ #define GNUNET_GNSRECORD_TYPE_CREDENTIAL 65547 /** * Record type for reverse lookups */ #define GNUNET_GNSRECORD_TYPE_REVERSE 65548 /** * Flags that can be set for a record. */ enum GNUNET_GNSRECORD_Flags { /** * No special options. */ GNUNET_GNSRECORD_RF_NONE = 0, /** * This is a private record of this peer and it should * thus not be handed out to other peers. */ GNUNET_GNSRECORD_RF_PRIVATE = 2, /** * This flag is currently unused; former RF_PENDING flag * * GNUNET_GNSRECORD_RF_UNUSED = 4, */ /** * This expiration time of the record is a relative * time (not an absolute time). */ GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION = 8, /** * This record should not be used unless all (other) records with an absolute * expiration time have expired. */ GNUNET_GNSRECORD_RF_SHADOW_RECORD = 16 /** * When comparing flags for record equality for removal, * which flags should must match (in addition to the type, * name, expiration value and data of the record)? All flags * that are not listed here will be ignored for this purpose. * (for example, we don't expect that users will remember to * pass the '--private' option when removing a record from * the namestore, hence we don't require this particular option * to match upon removal). See also * #GNUNET_GNSRECORD_records_cmp. */ #define GNUNET_GNSRECORD_RF_RCMP_FLAGS (GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION) }; /** * A GNS record. */ struct GNUNET_GNSRECORD_Data { /** * Binary value stored in the DNS record. Note: "data" must never * be individually 'malloc'ed, but instead always points into some * existing data area. */ const void *data; /** * Expiration time for the DNS record. Can be relative * or absolute, depending on @e flags. Measured in the same * unit as GNUnet time (microseconds). */ uint64_t expiration_time; /** * Number of bytes in @e data. */ size_t data_size; /** * Type of the GNS/DNS record. */ uint32_t record_type; /** * Flags for the record. */ enum GNUNET_GNSRECORD_Flags flags; }; GNUNET_NETWORK_STRUCT_BEGIN /** * Data stored in a PLACE record. */ struct GNUNET_GNSRECORD_PlaceData { /** * Public key of the place. */ struct GNUNET_CRYPTO_EddsaPublicKey place_pub_key; /** * Peer identity of the origin. */ struct GNUNET_PeerIdentity origin; /** * Number of relays that follow. */ uint32_t relay_count GNUNET_PACKED; /* Followed by struct GNUNET_PeerIdentity relays[relay_count] */ }; /** * Information we have in an encrypted block with record data (i.e. in the DHT). */ struct GNUNET_GNSRECORD_Block { /** * Signature of the block. */ struct GNUNET_CRYPTO_EcdsaSignature signature; /** * Derived key used for signing; hash of this is the query. */ struct GNUNET_CRYPTO_EcdsaPublicKey derived_key; /** * Number of bytes signed; also specifies the number of bytes * of encrypted data that follow. */ struct GNUNET_CRYPTO_EccSignaturePurpose purpose; /** * Expiration time of the block. */ struct GNUNET_TIME_AbsoluteNBO expiration_time; /* followed by encrypted data */ }; /** * Record type used to box up SRV and TLSA records. For example, a * TLSA record for "_https._tcp.foo.gnu" will be stored under * "foo.gnu" as a BOX record with service 443 (https) and protocol 6 * (tcp) and record_type "TLSA". When a BOX record is received, GNS * unboxes it if the name contained "_SERVICE._PROTO", otherwise GNS * leaves it untouched. This is done to ensure that TLSA (and SRV) * records do not require a separate network request, thus making TLSA * records inseparable from the "main" A/AAAA/VPN/etc. records. */ struct GNUNET_GNSRECORD_BoxRecord { /** * Protocol of the boxed record (6 = TCP, 17 = UDP, etc.). * Yes, in IP protocols are usually limited to 8 bits. In NBO. */ uint16_t protocol GNUNET_PACKED; /** * Service of the boxed record (aka port number), in NBO. */ uint16_t service GNUNET_PACKED; /** * GNS record type of the boxed record. In NBO. */ uint32_t record_type GNUNET_PACKED; /* followed by the 'original' record */ }; /** * Record type used internally to keep track of reverse mappings into a * namespace. * The record contains data related to PKEY delegations from other namespaces to * the namespace the record belongs to. * It is exclusively found under the label ``+''. */ struct GNUNET_GNSRECORD_ReverseRecord { /** * The public key of the namespace the is delegating to our namespace */ struct GNUNET_CRYPTO_EcdsaPublicKey pkey; /** * The expiration time of the delegation */ struct GNUNET_TIME_Absolute expiration; /* followed by the name the delegator uses to refer to our namespace */ }; GNUNET_NETWORK_STRUCT_END /** * Process a records that were decrypted from a block. * * @param cls closure * @param rd_count number of entries in @a rd array * @param rd array of records with data to store */ typedef void (*GNUNET_GNSRECORD_RecordCallback) (void *cls, unsigned int rd_count, const struct GNUNET_GNSRECORD_Data *rd); /* ***************** API related to GNSRECORD plugins ************** */ /** * Convert the binary value @a data of a record of * type @a type to a human-readable string. * * @param type type of the record * @param data value in binary encoding * @param data_size number of bytes in @a data * @return NULL on error, otherwise human-readable representation of the value */ char * GNUNET_GNSRECORD_value_to_string (uint32_t type, const void *data, size_t data_size); /** * Convert human-readable version of the value @a s of a record * of type @a type to the respective binary representation. * * @param type type of the record * @param s human-readable string * @param data set to value in binary encoding (will be allocated) * @param data_size set to number of bytes in @a data * @return #GNUNET_OK on success */ int GNUNET_GNSRECORD_string_to_value (uint32_t type, const char *s, void **data, size_t *data_size); /** * Convert a type name (i.e. "AAAA") to the corresponding number. * * @param dns_typename name to convert * @return corresponding number, UINT32_MAX on error */ uint32_t GNUNET_GNSRECORD_typename_to_number (const char *dns_typename); /** * Convert a type number (i.e. 1) to the corresponding type string (i.e. "A") * * @param type number of a type to convert * @return corresponding typestring, NULL on error */ const char * GNUNET_GNSRECORD_number_to_typename (uint32_t type); /* convenience APIs for serializing / deserializing GNS records */ /** * Calculate how many bytes we will need to serialize the given * records. * * @param rd_count number of records in the @a rd array * @param rd array of #GNUNET_GNSRECORD_Data with @a rd_count elements * @return the required size to serialize */ size_t GNUNET_GNSRECORD_records_get_size (unsigned int rd_count, const struct GNUNET_GNSRECORD_Data *rd); /** * Serialize the given records to the given destination buffer. * * @param rd_count number of records in the @a rd array * @param rd array of #GNUNET_GNSRECORD_Data with @a rd_count elements * @param dest_size size of the destination array @a dst * @param dest where to write the result * @return the size of serialized records, -1 if records do not fit */ ssize_t GNUNET_GNSRECORD_records_serialize (unsigned int rd_count, const struct GNUNET_GNSRECORD_Data *rd, size_t dest_size, char *dest); /** * Deserialize the given records to the given destination. * * @param len size of the serialized record data * @param src the serialized record data * @param rd_count number of records in the @a dest array * @param dest where to put the data * @return #GNUNET_OK on success, #GNUNET_SYSERR on error */ int GNUNET_GNSRECORD_records_deserialize (size_t len, const char *src, unsigned int rd_count, struct GNUNET_GNSRECORD_Data *dest); /* ******* general APIs relating to blocks, records and labels ******** */ /** * Test if a given record is expired. * * @param rd record to test * @return #GNUNET_YES if the record is expired, * #GNUNET_NO if not */ int GNUNET_GNSRECORD_is_expired (const struct GNUNET_GNSRECORD_Data *rd); /** * Convert a UTF-8 string to UTF-8 lowercase * @param src source string * @return converted result */ char * GNUNET_GNSRECORD_string_to_lowercase (const char *src); /** * Convert a zone to a string (for printing debug messages). * This is one of the very few calls in the entire API that is * NOT reentrant! * * @param z public key of a zone * @return string form; will be overwritten by next call to #GNUNET_GNSRECORD_z2s. */ const char * GNUNET_GNSRECORD_z2s (const struct GNUNET_CRYPTO_EcdsaPublicKey *z); /** * Convert public key to the respective absolute domain name in the * ".zkey" pTLD. * This is one of the very few calls in the entire API that is * NOT reentrant! * * @param pkey a public key with a point on the eliptic curve * @return string "X.zkey" where X is the coordinates of the public * key in an encoding suitable for DNS labels. */ const char * GNUNET_GNSRECORD_pkey_to_zkey (const struct GNUNET_CRYPTO_EcdsaPublicKey *pkey); /** * Convert an absolute domain name in the ".zkey" pTLD to the * respective public key. * * @param zkey string "X.zkey" where X is the public * key in an encoding suitable for DNS labels. * @param pkey set to a public key on the eliptic curve * @return #GNUNET_SYSERR if @a zkey has the wrong syntax */ int GNUNET_GNSRECORD_zkey_to_pkey (const char *zkey, struct GNUNET_CRYPTO_EcdsaPublicKey *pkey); /** * Calculate the DHT query for a given @a label in a given @a zone. * * @param zone private key of the zone * @param label label of the record * @param query hash to use for the query */ void GNUNET_GNSRECORD_query_from_private_key (const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone, const char *label, struct GNUNET_HashCode *query); /** * Calculate the DHT query for a given @a label in a given @a zone. * * @param pub public key of the zone * @param label label of the record * @param query hash to use for the query */ void GNUNET_GNSRECORD_query_from_public_key (const struct GNUNET_CRYPTO_EcdsaPublicKey *pub, const char *label, struct GNUNET_HashCode *query); /** * Sign name and records * * @param key the private key * @param expire block expiration * @param label the name for the records * @param rd record data * @param rd_count number of records in @a rd */ struct GNUNET_GNSRECORD_Block * GNUNET_GNSRECORD_block_create (const struct GNUNET_CRYPTO_EcdsaPrivateKey *key, struct GNUNET_TIME_Absolute expire, const char *label, const struct GNUNET_GNSRECORD_Data *rd, unsigned int rd_count); /** * Check if a signature is valid. This API is used by the GNS Block * to validate signatures received from the network. * * @param block block to verify * @return #GNUNET_OK if the signature is valid */ int GNUNET_GNSRECORD_block_verify (const struct GNUNET_GNSRECORD_Block *block); /** * Decrypt block. * * @param block block to decrypt * @param zone_key public key of the zone * @param label the name for the records * @param proc function to call with the result * @param proc_cls closure for @a proc * @return #GNUNET_OK on success, #GNUNET_SYSERR if the block was * not well-formed */ int GNUNET_GNSRECORD_block_decrypt (const struct GNUNET_GNSRECORD_Block *block, const struct GNUNET_CRYPTO_EcdsaPublicKey *zone_key, const char *label, GNUNET_GNSRECORD_RecordCallback proc, void *proc_cls); /** * Compares if two records are equal * * @param a a record * @param b another record * @return #GNUNET_YES if the records are equal, or #GNUNET_NO if not. */ int GNUNET_GNSRECORD_records_cmp (const struct GNUNET_GNSRECORD_Data *a, const struct GNUNET_GNSRECORD_Data *b); /** * Returns the expiration time of the given block of records. The block * expiration time is the expiration time of the record with smallest * expiration time. * * @param rd_count number of records given in @a rd * @param rd array of records * @return absolute expiration time */ struct GNUNET_TIME_Absolute GNUNET_GNSRECORD_record_get_expiration_time (unsigned int rd_count, const struct GNUNET_GNSRECORD_Data *rd); #if 0 /* keep Emacsens' auto-indent happy */ { #endif #ifdef __cplusplus } #endif #endif /** @} */ /* end of group */