/* Copyright (c) 2017 - 2019 LiteSpeed Technologies Inc. See LICENSE. */ #ifndef __LSQUIC_H__ #define __LSQUIC_H__ /** * @file * public API for using liblsquic is defined in this file. * */ #include #include #ifndef WIN32 #include #include #else #include #endif struct sockaddr; #ifdef __cplusplus extern "C" { #endif #define LSQUIC_MAJOR_VERSION 2 #define LSQUIC_MINOR_VERSION 7 #define LSQUIC_PATCH_VERSION 1 /** * Engine flags: */ /** Server mode */ #define LSENG_SERVER (1 << 0) /** Treat stream 3 as headers stream and, in general, behave like the * regular QUIC. */ #define LSENG_HTTP (1 << 1) #define LSENG_HTTP_SERVER (LSENG_SERVER|LSENG_HTTP) /** * This is a list of QUIC versions that we know of. List of supported * versions is in LSQUIC_SUPPORTED_VERSIONS. */ enum lsquic_version { /** Q035. This is the first version to be supported by LSQUIC. */ /* Support for this version has been removed. The comment remains to * document the changes. */ /* * Q037. This version is like Q035, except the way packet hashes are * generated is different for clients and servers. In addition, new * option NSTP (no STOP_WAITING frames) is rumored to be supported at * some point in the future. */ /* Support for this version has been removed. The comment remains to * document the changes. */ /* * Q038. Based on Q037, supports PADDING frames in the middle of packet * and NSTP (no STOP_WAITING frames) option. */ /* Support for this version has been removed. The comment remains to * document the changes. */ /** * Q039. Switch to big endian. Do not ack acks. Send connection level * WINDOW_UPDATE frame every 20 sent packets which do not contain * retransmittable frames. */ LSQVER_039, /* * Q041. RST_STREAM, ACK and STREAM frames match IETF format. */ /* Support for this version has been removed. The comment remains to * document the changes. */ /* * Q042. Receiving overlapping stream data is allowed. */ /* Support for this version has been removed. The comment remains to * document the changes. */ /** * Q043. Support for processing PRIORITY frames. Since this library * has supported PRIORITY frames from the beginning, this version is * exactly the same as LSQVER_042. */ LSQVER_043, /** * Q044. IETF-like packet headers are used. Frames are the same as * in Q043. Server never includes CIDs in short packets. */ /* Support for this version has been removed. The comment remains to * document the changes. */ /** * Q046. Use IETF Draft-17 compatible packet headers. */ LSQVER_046, #if LSQUIC_USE_Q098 /** * Q098. This is a made-up, experimental version used to test version * negotiation. The choice of 98 is similar to Google's choice of 99 * as the "IETF" version. */ LSQVER_098, #define LSQUIC_EXPERIMENTAL_Q098 (1 << LSQVER_098) #else #define LSQUIC_EXPERIMENTAL_Q098 0 #endif /** * IETF QUIC Draft-23 */ LSQVER_ID23, /** * IETF QUIC Draft-24 */ LSQVER_ID24, /** * Special version to trigger version negotiation. * [draft-ietf-quic-transport-11], Section 3. */ LSQVER_VERNEG, N_LSQVER }; /** * We currently support versions 39, 43, 46, and IETF Draft-23 * @see lsquic_version */ #define LSQUIC_SUPPORTED_VERSIONS ((1 << N_LSQVER) - 1) /** * List of versions in which the server never includes CID in short packets. */ #define LSQUIC_FORCED_TCID0_VERSIONS (1 << LSQVER_046) #define LSQUIC_EXPERIMENTAL_VERSIONS ( \ (1 << LSQVER_VERNEG) | LSQUIC_EXPERIMENTAL_Q098) #define LSQUIC_DEPRECATED_VERSIONS 0 #define LSQUIC_GQUIC_HEADER_VERSIONS ((1 << LSQVER_039) | (1 << LSQVER_043)) #define LSQUIC_IETF_VERSIONS ((1 << LSQVER_ID23) | (1 << LSQVER_ID24) \ | (1 << LSQVER_VERNEG)) #define LSQUIC_IETF_DRAFT_VERSIONS ((1 << LSQVER_ID23) | (1 << LSQVER_ID24) \ | (1 << LSQVER_VERNEG)) enum lsquic_hsk_status { /** * The handshake failed. */ LSQ_HSK_FAIL, /** * The handshake succeeded without 0-RTT. */ LSQ_HSK_OK, /** * The handshake succeeded with 0-RTT. */ LSQ_HSK_0RTT_OK, /** * The handshake failed because of 0-RTT (early data rejected). Retry * the connection without 0-RTT. */ LSQ_HSK_0RTT_FAIL, }; /** * @struct lsquic_stream_if * @brief The definition of callback functions call by lsquic_stream to * process events. * */ struct lsquic_stream_if { /** * Use @ref lsquic_conn_get_ctx to get back the context. It is * OK for this function to return NULL. */ lsquic_conn_ctx_t *(*on_new_conn)(void *stream_if_ctx, lsquic_conn_t *c); /** This is called when our side received GOAWAY frame. After this, * new streams should not be created. The callback is optional. */ void (*on_goaway_received)(lsquic_conn_t *c); void (*on_conn_closed)(lsquic_conn_t *c); /** If you need to initiate a connection, call lsquic_conn_make_stream(). * This will cause `on_new_stream' callback to be called when appropriate * (this operation is delayed when maximum number of outgoing streams is * reached). * * After `on_close' is called, the stream is no longer accessible. */ lsquic_stream_ctx_t * (*on_new_stream)(void *stream_if_ctx, lsquic_stream_t *s); void (*on_read) (lsquic_stream_t *s, lsquic_stream_ctx_t *h); void (*on_write) (lsquic_stream_t *s, lsquic_stream_ctx_t *h); void (*on_close) (lsquic_stream_t *s, lsquic_stream_ctx_t *h); /* This callback in only called in client mode */ /** * When handshake is completed, this callback is called. `ok' is set * to true if handshake was successful; otherwise, `ok' is set to * false. * * This callback is optional. */ void (*on_hsk_done)(lsquic_conn_t *c, enum lsquic_hsk_status s); /** * When server sends a token in NEW_TOKEN frame, this callback is called. * The callback is optional. */ void (*on_new_token)(lsquic_conn_t *c, const unsigned char *token, size_t token_size); /** * This optional callback lets client record information needed to * perform a zero-RTT handshake next time around. */ void (*on_zero_rtt_info)(lsquic_conn_t *c, const unsigned char *, size_t); }; struct ssl_ctx_st; struct ssl_st; /** * QUIC engine in server role needs access to certificates. This is * accomplished by providing a callback and a context to the engine * constructor. */ typedef struct ssl_ctx_st * (*lsquic_lookup_cert_f)( void *lsquic_cert_lookup_ctx, const struct sockaddr *local, const char *sni); /** * Minimum flow control window is set to 16 KB for both client and server. * This means we can send up to this amount of data before handshake gets * completed. */ #define LSQUIC_MIN_FCW (16 * 1024) /* Each LSQUIC_DF_* value corresponds to es_* entry in * lsquic_engine_settings below. */ /** * By default, deprecated and experimental versions are not included. */ #define LSQUIC_DF_VERSIONS (LSQUIC_SUPPORTED_VERSIONS & \ ~LSQUIC_DEPRECATED_VERSIONS & \ ~LSQUIC_EXPERIMENTAL_VERSIONS) #define LSQUIC_DF_CFCW_SERVER (3 * 1024 * 1024 / 2) #define LSQUIC_DF_CFCW_CLIENT (15 * 1024 * 1024) #define LSQUIC_DF_SFCW_SERVER (1 * 1024 * 1024) #define LSQUIC_DF_SFCW_CLIENT (6 * 1024 * 1024) #define LSQUIC_DF_MAX_STREAMS_IN 100 /* IQUIC uses different names for these: */ #define LSQUIC_DF_INIT_MAX_DATA_SERVER LSQUIC_DF_CFCW_SERVER #define LSQUIC_DF_INIT_MAX_DATA_CLIENT LSQUIC_DF_CFCW_CLIENT #define LSQUIC_DF_INIT_MAX_STREAM_DATA_BIDI_REMOTE_SERVER LSQUIC_DF_SFCW_SERVER #define LSQUIC_DF_INIT_MAX_STREAM_DATA_BIDI_LOCAL_SERVER 0 #define LSQUIC_DF_INIT_MAX_STREAM_DATA_BIDI_REMOTE_CLIENT 0 #define LSQUIC_DF_INIT_MAX_STREAM_DATA_BIDI_LOCAL_CLIENT LSQUIC_DF_SFCW_CLIENT #define LSQUIC_DF_INIT_MAX_STREAMS_BIDI LSQUIC_DF_MAX_STREAMS_IN #define LSQUIC_DF_INIT_MAX_STREAMS_UNI_CLIENT 100 #define LSQUIC_DF_INIT_MAX_STREAMS_UNI_SERVER 3 /* XXX What's a good value here? */ #define LSQUIC_DF_INIT_MAX_STREAM_DATA_UNI_CLIENT (32 * 1024) #define LSQUIC_DF_INIT_MAX_STREAM_DATA_UNI_SERVER (12 * 1024) /** * Default idle connection time in seconds. */ #define LSQUIC_DF_IDLE_TIMEOUT 30 /** * Default ping period in seconds. */ #define LSQUIC_DF_PING_PERIOD 15 /** * Default handshake timeout in microseconds. */ #define LSQUIC_DF_HANDSHAKE_TO (10 * 1000 * 1000) #define LSQUIC_DF_IDLE_CONN_TO (LSQUIC_DF_IDLE_TIMEOUT * 1000 * 1000) #define LSQUIC_DF_SILENT_CLOSE 1 /** Default value of maximum header list size. If set to non-zero value, * SETTINGS_MAX_HEADER_LIST_SIZE will be sent to peer after handshake is * completed (assuming the peer supports this setting frame type). */ #define LSQUIC_DF_MAX_HEADER_LIST_SIZE 0 /** Default value of UAID (user-agent ID). */ #define LSQUIC_DF_UA "LSQUIC" #define LSQUIC_DF_STTL 86400 #define LSQUIC_DF_MAX_INCHOATE (1 * 1000 * 1000) /** Do not use NSTP by default */ #define LSQUIC_DF_SUPPORT_NSTP 0 /** TODO: IETF QUIC clients do not support push */ #define LSQUIC_DF_SUPPORT_PUSH 1 #define LSQUIC_DF_SUPPORT_TCID0 1 /** By default, LSQUIC ignores Public Reset packets. */ #define LSQUIC_DF_HONOR_PRST 0 /** * By default, LSQUIC will not send Public Reset packets in response to * packets that specify unknown connections. */ #define LSQUIC_DF_SEND_PRST 0 /** By default, infinite loop checks are turned on */ #define LSQUIC_DF_PROGRESS_CHECK 1000 /** By default, read/write events are dispatched in a loop */ #define LSQUIC_DF_RW_ONCE 0 /** By default, the threshold is not enabled */ #define LSQUIC_DF_PROC_TIME_THRESH 0 /** By default, packets are paced */ #define LSQUIC_DF_PACE_PACKETS 1 /** Default clock granularity is 1000 microseconds */ #define LSQUIC_DF_CLOCK_GRANULARITY 1000 /** The default value is 8 for simplicity */ #define LSQUIC_DF_SCID_LEN 8 /** The default value is 60 CIDs per minute */ #define LSQUIC_DF_SCID_ISS_RATE 60 #define LSQUIC_DF_QPACK_DEC_MAX_BLOCKED 100 #define LSQUIC_DF_QPACK_DEC_MAX_SIZE 4096 #define LSQUIC_DF_QPACK_ENC_MAX_BLOCKED 100 #define LSQUIC_DF_QPACK_ENC_MAX_SIZE 4096 /** ECN is disabled by default */ #define LSQUIC_DF_ECN 0 /** Allow migration by default */ #define LSQUIC_DF_ALLOW_MIGRATION 1 /** Use QL loss bits by default */ #define LSQUIC_DF_QL_BITS 1 /* 1: Cubic; 2: BBR */ #define LSQUIC_DF_CC_ALGO 2 struct lsquic_engine_settings { /** * This is a bit mask wherein each bit corresponds to a value in * enum lsquic_version. Client starts negotiating with the highest * version and goes down. Server supports either of the versions * specified here. * * This setting applies to both Google and IETF QUIC. * * @see lsquic_version */ unsigned es_versions; /** * Initial default CFCW. * * In server mode, per-connection values may be set lower than * this if resources are scarce. * * Do not set es_cfcw and es_sfcw lower than @ref LSQUIC_MIN_FCW. * * @see es_max_cfcw */ unsigned es_cfcw; /** * Initial default SFCW. * * In server mode, per-connection values may be set lower than * this if resources are scarce. * * Do not set es_cfcw and es_sfcw lower than @ref LSQUIC_MIN_FCW. * * @see es_max_sfcw */ unsigned es_sfcw; /** * This value is used to specify maximum allowed value CFCW is allowed * to reach due to window auto-tuning. By default, this value is zero, * which means that CFCW is not allowed to increase from its initial * value. * * @see es_cfcw */ unsigned es_max_cfcw; unsigned es_max_sfcw; /** MIDS */ unsigned es_max_streams_in; /** * Handshake timeout in microseconds. * * For client, this can be set to an arbitrary value (zero turns the * timeout off). * * For server, this value is limited to about 16 seconds. Do not set * it to zero. */ unsigned long es_handshake_to; /** ICSL in microseconds; GQUIC only */ unsigned long es_idle_conn_to; /** SCLS (silent close) */ int es_silent_close; /** * This corresponds to SETTINGS_MAX_HEADER_LIST_SIZE * (RFC 7540, Section 6.5.2). 0 means no limit. Defaults * to @ref LSQUIC_DF_MAX_HEADER_LIST_SIZE. */ unsigned es_max_header_list_size; /** UAID -- User-Agent ID. Defaults to @ref LSQUIC_DF_UA. */ const char *es_ua; /** * More parameters for server */ uint64_t es_sttl; /* SCFG TTL in seconds */ uint32_t es_pdmd; /* One fixed value X509 */ uint32_t es_aead; /* One fixed value AESG */ uint32_t es_kexs; /* One fixed value C255 */ /* Maximum number of incoming connections in inchoate state. This is * only applicable in server mode. */ unsigned es_max_inchoate; /** * Setting this value to 0 means that * * For client: * a) we send a SETTINGS frame to indicate that we do not support server * push; and * b) All incoming pushed streams get reset immediately. * (For maximum effect, set es_max_streams_in to 0.) * * For server: * lsquic_conn_push_stream() will return -1. */ int es_support_push; /** * If set to true value, the server will not include connection ID in * outgoing packets if client's CHLO specifies TCID=0. * * For client, this means including TCID=0 into CHLO message. Note that * in this case, the engine tracks connections by the * (source-addr, dest-addr) tuple, thereby making it necessary to create * a socket for each connection. * * This option has no effect in Q046, as the server never includes * CIDs in the short packets. * * The default is @ref LSQUIC_DF_SUPPORT_TCID0. */ int es_support_tcid0; /** * Q037 and higher support "No STOP_WAITING frame" mode. When set, the * client will send NSTP option in its Client Hello message and will not * sent STOP_WAITING frames, while ignoring incoming STOP_WAITING frames, * if any. Note that if the version negotiation happens to downgrade the * client below Q037, this mode will *not* be used. * * This option does not affect the server, as it must support NSTP mode * if it was specified by the client. */ int es_support_nstp; /** * If set to true value, the library will drop connections when it * receives corresponding Public Reset packet. The default is to * ignore these packets. */ int es_honor_prst; /** * If set to true value, the library will send Public Reset packets * in response to incoming packets with unknown Connection IDs. * The default is @ref LSQUIC_DF_SEND_PRST. */ int es_send_prst; /** * A non-zero value enables internal checks that identify suspected * infinite loops in user @ref on_read and @ref on_write callbacks * and break them. An infinite loop may occur if user code keeps * on performing the same operation without checking status, e.g. * reading from a closed stream etc. * * The value of this parameter is as follows: should a callback return * this number of times in a row without making progress (that is, * reading, writing, or changing stream state), loop break will occur. * * The defaut value is @ref LSQUIC_DF_PROGRESS_CHECK. */ unsigned es_progress_check; /** * A non-zero value make stream dispatch its read-write events once * per call. * * When zero, read and write events are dispatched until the stream * is no longer readable or writeable, respectively, or until the * user signals unwillingness to read or write using * @ref lsquic_stream_wantread() or @ref lsquic_stream_wantwrite() * or shuts down the stream. * * The default value is @ref LSQUIC_DF_RW_ONCE. */ int es_rw_once; /** * If set, this value specifies that number of microseconds that * @ref lsquic_engine_process_conns() and * @ref lsquic_engine_send_unsent_packets() are allowed to spend * before returning. * * This is not an exact science and the connections must make * progress, so the deadline is checked after all connections get * a chance to tick (in the case of @ref lsquic_engine_process_conns()) * and at least one batch of packets is sent out. * * When processing function runs out of its time slice, immediate * calls to @ref lsquic_engine_has_unsent_packets() return false. * * The default value is @ref LSQUIC_DF_PROC_TIME_THRESH. */ unsigned es_proc_time_thresh; /** * If set to true, packet pacing is implemented per connection. * * The default value is @ref LSQUIC_DF_PACE_PACKETS. */ int es_pace_packets; /** * Clock granularity information is used by the pacer. The value * is in microseconds; default is @ref LSQUIC_DF_CLOCK_GRANULARITY. */ unsigned es_clock_granularity; /* The following settings are specific to IETF QUIC. */ /* vvvvvvvvvvv */ /** * Initial max data. * * This is a transport parameter. * * Depending on the engine mode, the default value is either * @ref LSQUIC_DF_INIT_MAX_DATA_CLIENT or * @ref LSQUIC_DF_INIT_MAX_DATA_SERVER. */ unsigned es_init_max_data; /** * Initial max stream data. * * This is a transport parameter. * * Depending on the engine mode, the default value is either * @ref LSQUIC_DF_INIT_MAX_STREAM_DATA_CLIENT or * @ref LSQUIC_DF_INIT_MAX_STREAM_DATA_BIDI_REMOTE_SERVER. */ unsigned es_init_max_stream_data_bidi_remote; unsigned es_init_max_stream_data_bidi_local; /** * Initial max stream data for unidirectional streams initiated * by remote endpoint. * * This is a transport parameter. * * Depending on the engine mode, the default value is either * @ref LSQUIC_DF_INIT_MAX_STREAM_DATA_UNI_CLIENT or * @ref LSQUIC_DF_INIT_MAX_STREAM_DATA_UNI_SERVER. */ unsigned es_init_max_stream_data_uni; /** * Maximum initial number of bidirectional stream. * * This is a transport parameter. * * Default value is @ref LSQUIC_DF_INIT_MAX_STREAMS_BIDI. */ unsigned es_init_max_streams_bidi; /** * Maximum initial number of unidirectional stream. * * This is a transport parameter. * * Default value is @ref LSQUIC_DF_INIT_MAX_STREAMS_UNI_CLIENT or * @ref LSQUIC_DF_INIT_MAX_STREAM_DATA_UNI_SERVER. */ unsigned es_init_max_streams_uni; /** * Idle connection timeout. * * This is a transport parameter. * * (Note: es_idle_conn_to is not reused because it is in microseconds, * which, I now realize, was not a good choice. Since it will be * obsoleted some time after the switchover to IETF QUIC, we do not * have to keep on using strange units.) * * Default value is @ref LSQUIC_DF_IDLE_TIMEOUT. * * Maximum value is 600 seconds. */ unsigned es_idle_timeout; /** * Ping period. If set to non-zero value, the connection will generate and * send PING frames in the absence of other activity. * * By default, the server does not send PINGs and the period is set to zero. * The client's defaut value is @ref LSQUIC_DF_PING_PERIOD. */ unsigned es_ping_period; /** * Source Connection ID length. Only applicable to the IETF QUIC * versions. Valid values are 4 through 18, inclusive. * * Default value is @ref LSQUIC_DF_SCID_LEN. */ unsigned es_scid_len; /** * Source Connection ID issuance rate. Only applicable to the IETF QUIC * versions. This field is measured in CIDs per minute. Using value 0 * indicates that there is no rate limit for CID issuance. * * Default value is @ref LSQUIC_DF_SCID_ISS_RATE. */ unsigned es_scid_iss_rate; /** * Maximum size of the QPACK dynamic table that the QPACK decoder will * use. * * The default is @ref LSQUIC_DF_QPACK_DEC_MAX_SIZE. */ unsigned es_qpack_dec_max_size; /** * Maximum number of blocked streams that the QPACK decoder is willing * to tolerate. * * The default is @ref LSQUIC_DF_QPACK_DEC_MAX_BLOCKED. */ unsigned es_qpack_dec_max_blocked; /** * Maximum size of the dynamic table that the encoder is willing to use. * The actual size of the dynamic table will not exceed the minimum of * this value and the value advertized by peer. * * The default is @ref LSQUIC_DF_QPACK_ENC_MAX_SIZE. */ unsigned es_qpack_enc_max_size; /** * Maximum number of blocked streams that the QPACK encoder is willing * to risk. The actual number of blocked streams will not exceed the * minimum of this value and the value advertized by peer. * * The default is @ref LSQUIC_DF_QPACK_ENC_MAX_BLOCKED. */ unsigned es_qpack_enc_max_blocked; /** * Enable ECN support. * * The default is @ref LSQUIC_DF_ECN */ int es_ecn; /** * Allow peer to migrate connection. * * The default is @ref LSQUIC_DF_ALLOW_MIGRATION */ int es_allow_migration; /** * Congestion control algorithm to use. * * 0: Use default (@ref LSQUIC_DF_CC_ALGO) * 1: Cubic * 2: BBR */ unsigned es_cc_algo; /** * Use QL loss bits. * * Default value is @ref LSQUIC_DF_QL_BITS */ int es_ql_bits; }; /* Initialize `settings' to default values */ void lsquic_engine_init_settings (struct lsquic_engine_settings *, unsigned lsquic_engine_flags); /** * Check settings for errors. * * @param settings Settings struct. * * @param flags Engine flags. * * @param err_buf Optional pointer to buffer into which error string * is written. * @param err_buf_sz Size of err_buf. No more than this number of bytes * will be written to err_buf, including the NUL byte. * * @retval 0 Settings have no errors. * @retval -1 There are errors in settings. */ int lsquic_engine_check_settings (const struct lsquic_engine_settings *settings, unsigned lsquic_engine_flags, char *err_buf, size_t err_buf_sz); struct lsquic_out_spec { struct iovec *iov; size_t iovlen; const struct sockaddr *local_sa; const struct sockaddr *dest_sa; void *peer_ctx; int ecn; /* Valid values are 0 - 3. See RFC 3168 */ }; /** * Returns number of packets successfully sent out or -1 on error. -1 should * only be returned if no packets were sent out. If -1 is returned or if the * return value is smaller than `n_packets_out', this indicates that sending * of packets is not possible. * * If not all packets could be sent out, errno is examined. If it is not * EAGAIN or EWOULDBLOCK, the connection whose packet cause the error is * closed forthwith. * * No packets will be attempted to be sent out until * @ref lsquic_engine_send_unsent_packets() is called. */ typedef int (*lsquic_packets_out_f)( void *packets_out_ctx, const struct lsquic_out_spec *out_spec, unsigned n_packets_out ); /** * The shared hash interface is used to share data between multiple LSQUIC * instances. */ struct lsquic_shared_hash_if { /** * If you want your item to never expire, set `expiry' to zero. * Returns 0 on success, -1 on failure. * * If inserted successfully, `free()' will be called on `data' and 'key' * pointer when the element is deleted, whether due to expiration * or explicit deletion. */ int (*shi_insert)(void *shi_ctx, void *key, unsigned key_sz, void *data, unsigned data_sz, time_t expiry); /** * Returns 0 on success, -1 on failure. */ int (*shi_delete)(void *shi_ctx, const void *key, unsigned key_sz); /** * `data' is pointed to the result and `data_sz' is set to the * object size. The implementation may choose to copy the object * into buffer pointed to by `data', so you should have it ready. * * @retval 1 found. * @retval 0 not found. * @retval -1 error (perhaps not enough room in `data' if copy was * attempted). */ int (*shi_lookup)(void *shi_ctx, const void *key, unsigned key_sz, void **data, unsigned *data_sz); }; /** * The packet out memory interface is used by LSQUIC to get buffers to * which outgoing packets will be written before they are passed to * ea_packets_out callback. * * If not specified, malloc() and free() are used. */ struct lsquic_packout_mem_if { /** * Allocate buffer for sending. */ void * (*pmi_allocate) (void *pmi_ctx, void *conn_ctx, unsigned short sz, char is_ipv6); /** * This function is used to release the allocated buffer after it is * sent via @ref ea_packets_out. */ void (*pmi_release) (void *pmi_ctx, void *conn_ctx, void *buf, char is_ipv6); /** * If allocated buffer is not going to be sent, return it to the caller * using this function. */ void (*pmi_return) (void *pmi_ctx, void *conn_ctx, void *buf, char is_ipv6); }; typedef void (*lsquic_cids_update_f)(void *ctx, void **peer_ctx, const lsquic_cid_t *cids, unsigned n_cids); struct stack_st_X509; /** * When headers are processed, various errors may occur. They are listed * in this enum. */ enum lsquic_header_status { LSQUIC_HDR_OK, /** Duplicate pseudo-header */ LSQUIC_HDR_ERR_DUPLICATE_PSDO_HDR, /** Not all request pseudo-headers are present */ LSQUIC_HDR_ERR_INCOMPL_REQ_PSDO_HDR, /** Unnecessary request pseudo-header present in the response */ LSQUIC_HDR_ERR_UNNEC_REQ_PSDO_HDR, /** Prohibited header in request */ LSQUIC_HDR_ERR_BAD_REQ_HEADER, /** Not all response pseudo-headers are present */ LSQUIC_HDR_ERR_INCOMPL_RESP_PSDO_HDR, /** Unnecessary response pseudo-header present in the response. */ LSQUIC_HDR_ERR_UNNEC_RESP_PSDO_HDR, /** Unknown pseudo-header */ LSQUIC_HDR_ERR_UNKNOWN_PSDO_HDR, /** Uppercase letter in header */ LSQUIC_HDR_ERR_UPPERCASE_HEADER, /** Misplaced pseudo-header */ LSQUIC_HDR_ERR_MISPLACED_PSDO_HDR, /** Missing pseudo-header */ LSQUIC_HDR_ERR_MISSING_PSDO_HDR, /** Header or headers are too large */ LSQUIC_HDR_ERR_HEADERS_TOO_LARGE, /** Cannot allocate any more memory. */ LSQUIC_HDR_ERR_NOMEM, }; struct lsquic_hset_if { /** * Create a new header set. This object is (and must be) fetched from a * stream by calling @ref lsquic_stream_get_hset() before the stream can * be read. */ void * (*hsi_create_header_set)(void *hsi_ctx, int is_push_promise); /** * Process new header. Return 0 on success, -1 if there is a problem with * the header. -1 is treated as a stream error: the associated stream is * reset. * * `hdr_set' is the header set object returned by * @ref hsi_create_header_set(). * * `name_idx' is set to the index in either the HPACK or QPACK static table * whose entry's name element matches `name'. The values are as follows: * - if there is no such match, `name_idx' is set to zero; * - if HPACK is used, the value is between 1 and 61; and * - if QPACK is used, the value is 62+ (subtract 62 to get the QPACK * static table index). * * If `name' is NULL, this means that no more header are going to be * added to the set. */ enum lsquic_header_status (*hsi_process_header)(void *hdr_set, unsigned name_idx, const char *name, unsigned name_len, const char *value, unsigned value_len); /** * Discard header set. This is called for unclaimed header sets and * header sets that had an error. */ void (*hsi_discard_header_set)(void *hdr_set); }; /** * SSL keylog interface. */ struct lsquic_keylog_if { /** Return keylog handle or NULL if no key logging is desired */ void * (*kli_open) (void *keylog_ctx, lsquic_conn_t *); /** * Log line. The first argument is the pointer returned by * @ref kli_open. */ void (*kli_log_line) (void *handle, const char *line); /** * Close handle. */ void (*kli_close) (void *handle); }; /* TODO: describe this important data structure */ typedef struct lsquic_engine_api { const struct lsquic_engine_settings *ea_settings; /* Optional */ const struct lsquic_stream_if *ea_stream_if; void *ea_stream_if_ctx; lsquic_packets_out_f ea_packets_out; void *ea_packets_out_ctx; lsquic_lookup_cert_f ea_lookup_cert; void *ea_cert_lu_ctx; struct ssl_ctx_st * (*ea_get_ssl_ctx)(void *peer_ctx); /** * Shared hash interface is optional. If set to zero, performance of * multiple LSQUIC instances will be degraded. */ const struct lsquic_shared_hash_if *ea_shi; void *ea_shi_ctx; /** * Memory interface is optional. */ const struct lsquic_packout_mem_if *ea_pmi; void *ea_pmi_ctx; /** * Optional interface to report new and old source connection IDs. */ lsquic_cids_update_f ea_new_scids; lsquic_cids_update_f ea_live_scids; lsquic_cids_update_f ea_old_scids; void *ea_cids_update_ctx; /** * Function to verify server certificate. The chain contains at least * one element. The first element in the chain is the server * certificate. The chain belongs to the library. If you want to * retain it, call sk_X509_up_ref(). * * 0 is returned on success, -1 on error. * * If the function pointer is not set, no verification is performed * (the connection is allowed to proceed). */ int (*ea_verify_cert)(void *verify_ctx, struct stack_st_X509 *chain); void *ea_verify_ctx; /** * Optional header set interface. If not specified, the incoming headers * are converted to HTTP/1.x format and are read from stream and have to * be parsed again. */ const struct lsquic_hset_if *ea_hsi_if; void *ea_hsi_ctx; #if LSQUIC_CONN_STATS /** * If set, engine will print cumulative connection statistics to this * file just before it is destroyed. */ void /* FILE, really */ *ea_stats_fh; #endif /** * Optional SSL key logging interface. */ const struct lsquic_keylog_if *ea_keylog_if; void *ea_keylog_ctx; } lsquic_engine_api_t; /** * Create new engine. * * @param lsquic_engine_flags A bitmask of @ref LSENG_SERVER and * @ref LSENG_HTTP */ lsquic_engine_t * lsquic_engine_new (unsigned lsquic_engine_flags, const struct lsquic_engine_api *); /** * Create a client connection to peer identified by `peer_ctx'. * * To let the engine specify QUIC version, use N_LSQVER. If zero-rtt info * is supplied, version is picked from there instead. * * If `max_packet_size' is set to zero, it is inferred based on `peer_sa': * 1350 for IPv6 and 1370 for IPv4. */ lsquic_conn_t * lsquic_engine_connect (lsquic_engine_t *, enum lsquic_version, const struct sockaddr *local_sa, const struct sockaddr *peer_sa, void *peer_ctx, lsquic_conn_ctx_t *conn_ctx, const char *hostname, unsigned short max_packet_size, const unsigned char *zero_rtt, size_t zero_rtt_len, /** Resumption token: optional */ const unsigned char *token, size_t token_sz); /** * Pass incoming packet to the QUIC engine. This function can be called * more than once in a row. After you add one or more packets, call * lsquic_engine_process_conns() to schedule output, if any. * * @retval 0 Packet was processed by a real connection. * * @retval 1 Packet was handled successfully, but not by a connection. * This may happen with version negotiation and public reset * packets as well as some packets that may be ignored. * * @retval -1 Some error occurred. Possible reasons are invalid packet * size or failure to allocate memory. */ int lsquic_engine_packet_in (lsquic_engine_t *, const unsigned char *packet_in_data, size_t packet_in_size, const struct sockaddr *sa_local, const struct sockaddr *sa_peer, void *peer_ctx, int ecn); /** * Process tickable connections. This function must be called often enough so * that packets and connections do not expire. */ void lsquic_engine_process_conns (lsquic_engine_t *engine); /** * Returns true if engine has some unsent packets. This happens if * @ref ea_packets_out() could not send everything out. */ int lsquic_engine_has_unsent_packets (lsquic_engine_t *engine); /** * Send out as many unsent packets as possibe: until we are out of unsent * packets or until @ref ea_packets_out() fails. * * If @ref ea_packets_out() does fail (that is, it returns an error), this * function must be called to signify that sending of packets is possible * again. */ void lsquic_engine_send_unsent_packets (lsquic_engine_t *engine); void lsquic_engine_destroy (lsquic_engine_t *); /** Return max allowed outbound streams less current outbound streams. */ unsigned lsquic_conn_n_avail_streams (const lsquic_conn_t *); void lsquic_conn_make_stream (lsquic_conn_t *); /** Return number of delayed streams currently pending */ unsigned lsquic_conn_n_pending_streams (const lsquic_conn_t *); /** Cancel `n' pending streams. Returns new number of pending streams. */ unsigned lsquic_conn_cancel_pending_streams (lsquic_conn_t *, unsigned n); /** * Mark connection as going away: send GOAWAY frame and do not accept * any more incoming streams, nor generate streams of our own. * * In the server mode, of course, we can call this function just fine in both * Google and IETF QUIC. * * In client mode, calling this function in for an IETF QUIC connection does * not do anything, as the client MUST NOT send GOAWAY frames. * See [draft-ietf-quic-http-17] Section 4.2.7. */ void lsquic_conn_going_away (lsquic_conn_t *); /** * This forces connection close. on_conn_closed and on_close callbacks * will be called. */ void lsquic_conn_close (lsquic_conn_t *); int lsquic_stream_wantread(lsquic_stream_t *s, int is_want); ssize_t lsquic_stream_read(lsquic_stream_t *s, void *buf, size_t len); ssize_t lsquic_stream_readv(lsquic_stream_t *s, const struct iovec *, int iovcnt); /** * This function allows user-supplied callback to read the stream contents. * It is meant to be used for zero-copy stream processing. */ ssize_t lsquic_stream_readf (lsquic_stream_t *s, /** * The callback takes four parameters: * - Pointer to user-supplied context; * - Pointer to the data; * - Data size (can be zero); and * - Indicator whether the FIN follows the data. * * The callback returns number of bytes processed. If this number is zero * or is smaller than `len', reading from stream stops. */ size_t (*readf)(void *ctx, const unsigned char *buf, size_t len, int fin), void *ctx); int lsquic_stream_wantwrite(lsquic_stream_t *s, int is_want); /** * Write `len' bytes to the stream. Returns number of bytes written, which * may be smaller that `len'. */ ssize_t lsquic_stream_write(lsquic_stream_t *s, const void *buf, size_t len); ssize_t lsquic_stream_writev(lsquic_stream_t *s, const struct iovec *vec, int count); /** * Used as argument to @ref lsquic_stream_writef() */ struct lsquic_reader { /** * Not a ssize_t because the read function is not supposed to return * an error. If an error occurs in the read function (for example, when * reading from a file fails), it is supposed to deal with the error * itself. */ size_t (*lsqr_read) (void *lsqr_ctx, void *buf, size_t count); /** * Return number of bytes remaining in the reader. */ size_t (*lsqr_size) (void *lsqr_ctx); void *lsqr_ctx; }; /** * Write to stream using @ref lsquic_reader. This is the most generic of * the write functions -- @ref lsquic_stream_write() and * @ref lsquic_stream_writev() utilize the same mechanism. * * @retval Number of bytes written or -1 on error. */ ssize_t lsquic_stream_writef (lsquic_stream_t *, struct lsquic_reader *); /** * Flush any buffered data. This triggers packetizing even a single byte * into a separate frame. Flushing a closed stream is an error. * * @retval 0 Success * @retval -1 Failure */ int lsquic_stream_flush (lsquic_stream_t *s); /** * @typedef lsquic_http_header_t * @brief HTTP header structure. Contains header name and value. * */ typedef struct lsquic_http_header { struct iovec name; struct iovec value; } lsquic_http_header_t; /** * @typedef lsquic_http_headers_t * @brief HTTP header list structure. Contains a list of HTTP headers in key/value pairs. * used in API functions to pass headers. */ struct lsquic_http_headers { int count; lsquic_http_header_t *headers; }; int lsquic_stream_send_headers(lsquic_stream_t *s, const lsquic_http_headers_t *h, int eos); /** * Get header set associated with the stream. The header set is created by * @ref hsi_create_header_set() callback. After this call, the ownership of * the header set is trasnferred to the caller. * * This call must precede calls to @ref lsquic_stream_read() and * @ref lsquic_stream_readv(). * * If the optional header set interface (@ref ea_hsi_if) is not specified, * this function returns NULL. */ void * lsquic_stream_get_hset (lsquic_stream_t *); /** * A server may push a stream. This call creates a new stream in reference * to stream `s'. It will behave as if the client made a request: it will * trigger on_new_stream() event and it can be used as a regular client- * initiated stream. * * If `hdr_set' is not set, it is generated by using `ea_hsi_if' callbacks. * In either case, the header set object belongs to the connection. The * user is not to free this object until (@ref hsi_discard_header_set) is * called. * * @retval 0 Stream pushed successfully. * @retval 1 Stream push failed because it is disabled or because we hit * stream limit or connection is going away. * @retval -1 Stream push failed because of an internal error. */ int lsquic_conn_push_stream (lsquic_conn_t *c, void *hdr_set, lsquic_stream_t *s, const struct iovec* url, const struct iovec* authority, const lsquic_http_headers_t *headers); /** * Only makes sense in server mode: the client cannot push a stream and this * function always returns false in client mode. */ int lsquic_conn_is_push_enabled (lsquic_conn_t *); /** Possible values for how are 0, 1, and 2. See shutdown(2). */ int lsquic_stream_shutdown(lsquic_stream_t *s, int how); int lsquic_stream_close(lsquic_stream_t *s); /** * Get certificate chain returned by the server. This can be used for * server certificate verification. * * If server certificate cannot be verified, the connection can be closed * using lsquic_conn_cert_verification_failed(). * * The caller releases the stack using sk_X509_free(). */ struct stack_st_X509 * lsquic_conn_get_server_cert_chain (lsquic_conn_t *); /** Returns ID of the stream */ lsquic_stream_id_t lsquic_stream_id (const lsquic_stream_t *s); /** * Returns stream ctx associated with the stream. (The context is what * is returned by @ref on_new_stream callback). */ lsquic_stream_ctx_t * lsquic_stream_get_ctx (const lsquic_stream_t *s); /** Returns true if this is a pushed stream */ int lsquic_stream_is_pushed (const lsquic_stream_t *s); /** * Returns true if this stream was rejected, false otherwise. Use this as * an aid to distinguish between errors. */ int lsquic_stream_is_rejected (const lsquic_stream_t *s); /** * Refuse pushed stream. Call it from @ref on_new_stream. * * No need to call lsquic_stream_close() after this. on_close will be called. * * @see lsquic_stream_is_pushed */ int lsquic_stream_refuse_push (lsquic_stream_t *s); /** * Get information associated with pushed stream: * * @param ref_stream_id Stream ID in response to which push promise was * sent. * @param hdr_set Header set. This object was passed to or generated * by @ref lsquic_conn_push_stream(). * * @retval 0 Success. * @retval -1 This is not a pushed stream. */ int lsquic_stream_push_info (const lsquic_stream_t *, lsquic_stream_id_t *ref_stream_id, void **hdr_set); /** Return current priority of the stream */ unsigned lsquic_stream_priority (const lsquic_stream_t *s); /** * Set stream priority. Valid priority values are 1 through 256, inclusive. * * @retval 0 Success. * @retval -1 Priority value is invalid. */ int lsquic_stream_set_priority (lsquic_stream_t *s, unsigned priority); /** * Get a pointer to the connection object. Use it with lsquic_conn_* * functions. */ lsquic_conn_t * lsquic_stream_conn(const lsquic_stream_t *s); lsquic_stream_t * lsquic_conn_get_stream_by_id (lsquic_conn_t *c, lsquic_stream_id_t stream_id); /** Get connection ID */ const lsquic_cid_t * lsquic_conn_id (const lsquic_conn_t *c); /** Get pointer to the engine */ lsquic_engine_t * lsquic_conn_get_engine (lsquic_conn_t *c); int lsquic_conn_get_sockaddr(lsquic_conn_t *c, const struct sockaddr **local, const struct sockaddr **peer); struct lsquic_logger_if { int (*log_buf)(void *logger_ctx, const char *buf, size_t len); }; /** * Enumerate timestamp styles supported by LSQUIC logger mechanism. */ enum lsquic_logger_timestamp_style { /** * No timestamp is generated. */ LLTS_NONE, /** * The timestamp consists of 24 hours, minutes, seconds, and * milliseconds. Example: 13:43:46.671 */ LLTS_HHMMSSMS, /** * Like above, plus date, e.g: 2017-03-21 13:43:46.671 */ LLTS_YYYYMMDD_HHMMSSMS, /** * This is Chrome-like timestamp used by proto-quic. The timestamp * includes month, date, hours, minutes, seconds, and microseconds. * * Example: 1223/104613.946956 (instead of 12/23 10:46:13.946956). * * This is to facilitate reading two logs side-by-side. */ LLTS_CHROMELIKE, /** * The timestamp consists of 24 hours, minutes, seconds, and * microseconds. Example: 13:43:46.671123 */ LLTS_HHMMSSUS, /** * Date and time using microsecond resolution, * e.g: 2017-03-21 13:43:46.671123 */ LLTS_YYYYMMDD_HHMMSSUS, N_LLTS }; /** * Call this if you want to do something with LSQUIC log messages, as they * are thrown out by default. */ void lsquic_logger_init(const struct lsquic_logger_if *, void *logger_ctx, enum lsquic_logger_timestamp_style); /** * Set log level for all LSQUIC modules. Acceptable values are debug, info, * notice, warning, error, alert, emerg, crit (case-insensitive). * * @retval 0 Success. * @retval -1 Failure: log_level is not valid. */ int lsquic_set_log_level (const char *log_level); /** * E.g. "event=debug" */ int lsquic_logger_lopt (const char *optarg); /** * Return the list of QUIC versions (as bitmask) this engine instance * supports. */ unsigned lsquic_engine_quic_versions (const lsquic_engine_t *); /** * This is one of the flags that can be passed to @ref lsquic_global_init. * Use it to initialize LSQUIC for use in client mode. */ #define LSQUIC_GLOBAL_CLIENT (1 << 0) /** * This is one of the flags that can be passed to @ref lsquic_global_init. * Use it to initialize LSQUIC for use in server mode. */ #define LSQUIC_GLOBAL_SERVER (1 << 1) /** * Initialize LSQUIC. This must be called before any other LSQUIC function * is called. Returns 0 on success and -1 on failure. * * @param flags This a bitmask of @ref LSQUIC_GLOBAL_CLIENT and * @ref LSQUIC_GLOBAL_SERVER. At least one of these * flags should be specified. * * @retval 0 Success. * @retval -1 Initialization failed. * * @see LSQUIC_GLOBAL_CLIENT * @see LSQUIC_GLOBAL_SERVER */ int lsquic_global_init (int flags); /** * Clean up global state created by @ref lsquic_global_init. Should be * called after all LSQUIC engine instances are gone. */ void lsquic_global_cleanup (void); /** * Get QUIC version used by the connection. * * @see lsquic_version */ enum lsquic_version lsquic_conn_quic_version (const lsquic_conn_t *c); /* Return keysize or -1 on error */ int lsquic_conn_crypto_keysize (const lsquic_conn_t *c); /* Return algorithm keysize or -1 on error */ int lsquic_conn_crypto_alg_keysize (const lsquic_conn_t *c); enum lsquic_crypto_ver { LSQ_CRY_QUIC, LSQ_CRY_TLSv13, }; enum lsquic_crypto_ver lsquic_conn_crypto_ver (const lsquic_conn_t *c); /* Return cipher or NULL on error */ const char * lsquic_conn_crypto_cipher (const lsquic_conn_t *c); /** Translate string QUIC version to LSQUIC QUIC version representation */ enum lsquic_version lsquic_str2ver (const char *str, size_t len); /** Translate ALPN (e.g. "h3", "h3-23", "h3-Q046") to LSQUIC enum */ enum lsquic_version lsquic_alpn2ver (const char *alpn, size_t len); /** * This function closes all mini connections and marks all full connections * as going away. In server mode, this also causes the engine to stop * creating new connections. */ void lsquic_engine_cooldown (lsquic_engine_t *); struct ssl_st * lsquic_hsk_getssl(lsquic_conn_t *conn); /** * Get user-supplied context associated with the connection. */ lsquic_conn_ctx_t * lsquic_conn_get_ctx (const lsquic_conn_t *); /** * Set user-supplied context associated with the connection. */ void lsquic_conn_set_ctx (lsquic_conn_t *, lsquic_conn_ctx_t *); /** * Get peer context associated with the connection. */ void * lsquic_conn_get_peer_ctx (lsquic_conn_t *, const struct sockaddr *local_sa); /** * Abort connection. */ void lsquic_conn_abort (lsquic_conn_t *); /** * Helper function: convert list of versions as specified in the argument * bitmask to string that can be included as argument to "v=" part of the * Alt-Svc header. * * For example (1< "37,38" * * This is only applicable to Google QUIC versions. */ const char * lsquic_get_alt_svc_versions (unsigned versions); /** * Return a NULL-terminated list of HTTP/3 ALPNs, e.g "h3-17", "h3-18", "h3". */ const char *const * lsquic_get_h3_alpns (unsigned versions); /** * Returns true if provided buffer could be a valid handshake-stage packet, * false otherwise. Do not call this function if a connection has already * been established: it will return incorrect result. */ int lsquic_is_valid_hs_packet (lsquic_engine_t *, const unsigned char *, size_t); /** * Parse cid from packet stored in `buf' and store it to `cid'. Returns 0 * on success and -1 on failure. */ int lsquic_cid_from_packet (const unsigned char *, size_t bufsz, lsquic_cid_t *cid); /** * Returns true if there are connections to be processed, false otherwise. * If true, `diff' is set to the difference between the earliest advisory * tick time and now. If the former is in the past, the value of `diff' * is negative. */ int lsquic_engine_earliest_adv_tick (lsquic_engine_t *engine, int *diff); /** * Return number of connections whose advisory tick time is before current * time plus `from_now' microseconds from now. `from_now' can be negative. */ unsigned lsquic_engine_count_attq (lsquic_engine_t *engine, int from_now); enum LSQUIC_CONN_STATUS { LSCONN_ST_HSK_IN_PROGRESS, LSCONN_ST_CONNECTED, LSCONN_ST_HSK_FAILURE, LSCONN_ST_GOING_AWAY, LSCONN_ST_TIMED_OUT, /* If es_honor_prst is not set, the connection will never get public * reset packets and this flag will not be set. */ LSCONN_ST_RESET, LSCONN_ST_USER_ABORTED, LSCONN_ST_ERROR, LSCONN_ST_CLOSED, LSCONN_ST_PEER_GOING_AWAY, }; enum LSQUIC_CONN_STATUS lsquic_conn_status (lsquic_conn_t *, char *errbuf, size_t bufsz); extern const char *const lsquic_ver2str[N_LSQVER]; #ifdef __cplusplus } #endif #endif //__LSQUIC_H__