Mercurial > hg > nginx
view src/event/quic/ngx_event_quic_connid.c @ 8798:fc5719637aff quic
QUIC: consistent use of 5-byte buffers for header protection.
The output buffer is now also of 5 bytes. Header protection uses
stream ciphers, which don't produce extra output nor PKCS padding.
author | Sergey Kandaurov <pluknet@nginx.com> |
---|---|
date | Wed, 16 Jun 2021 17:53:18 +0300 |
parents | 4715f3e669f1 |
children | e2ec952dc295 |
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/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_event_quic_connection.h> #define NGX_QUIC_MAX_SERVER_IDS 8 #if (NGX_QUIC_BPF) static ngx_int_t ngx_quic_bpf_attach_id(ngx_connection_t *c, u_char *id); #endif static ngx_int_t ngx_quic_send_retire_connection_id(ngx_connection_t *c, uint64_t seqnum); static ngx_quic_client_id_t *ngx_quic_alloc_client_id(ngx_connection_t *c, ngx_quic_connection_t *qc); static ngx_int_t ngx_quic_replace_retired_client_id(ngx_connection_t *c, ngx_quic_client_id_t *retired_cid); static ngx_int_t ngx_quic_send_server_id(ngx_connection_t *c, ngx_quic_server_id_t *sid); ngx_int_t ngx_quic_create_server_id(ngx_connection_t *c, u_char *id) { if (RAND_bytes(id, NGX_QUIC_SERVER_CID_LEN) != 1) { return NGX_ERROR; } #if (NGX_QUIC_BPF) if (ngx_quic_bpf_attach_id(c, id) != NGX_OK) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "quic bpf failed to generate socket key"); /* ignore error, things still may work */ } #endif return NGX_OK; } #if (NGX_QUIC_BPF) static ngx_int_t ngx_quic_bpf_attach_id(ngx_connection_t *c, u_char *id) { int fd; uint64_t cookie; socklen_t optlen; fd = c->listening->fd; optlen = sizeof(cookie); if (getsockopt(fd, SOL_SOCKET, SO_COOKIE, &cookie, &optlen) == -1) { ngx_log_error(NGX_LOG_ERR, c->log, ngx_socket_errno, "quic getsockopt(SO_COOKIE) failed"); return NGX_ERROR; } ngx_quic_dcid_encode_key(id, cookie); return NGX_OK; } #endif ngx_int_t ngx_quic_handle_new_connection_id_frame(ngx_connection_t *c, ngx_quic_new_conn_id_frame_t *f) { ngx_str_t id; ngx_queue_t *q; ngx_quic_client_id_t *cid, *item; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); if (f->seqnum < qc->max_retired_seqnum) { /* * RFC 9000, 19.15. NEW_CONNECTION_ID Frame * * An endpoint that receives a NEW_CONNECTION_ID frame with * a sequence number smaller than the Retire Prior To field * of a previously received NEW_CONNECTION_ID frame MUST send * a corresponding RETIRE_CONNECTION_ID frame that retires * the newly received connection ID, unless it has already * done so for that sequence number. */ if (ngx_quic_send_retire_connection_id(c, f->seqnum) != NGX_OK) { return NGX_ERROR; } goto retire; } cid = NULL; for (q = ngx_queue_head(&qc->client_ids); q != ngx_queue_sentinel(&qc->client_ids); q = ngx_queue_next(q)) { item = ngx_queue_data(q, ngx_quic_client_id_t, queue); if (item->seqnum == f->seqnum) { cid = item; break; } } if (cid) { /* * Transmission errors, timeouts, and retransmissions might cause the * same NEW_CONNECTION_ID frame to be received multiple times. */ if (cid->len != f->len || ngx_strncmp(cid->id, f->cid, f->len) != 0 || ngx_strncmp(cid->sr_token, f->srt, NGX_QUIC_SR_TOKEN_LEN) != 0) { /* * ..if a sequence number is used for different connection IDs, * the endpoint MAY treat that receipt as a connection error * of type PROTOCOL_VIOLATION. */ qc->error = NGX_QUIC_ERR_PROTOCOL_VIOLATION; qc->error_reason = "seqnum refers to different connection id/token"; return NGX_ERROR; } } else { id.data = f->cid; id.len = f->len; if (ngx_quic_create_client_id(c, &id, f->seqnum, f->srt) == NULL) { return NGX_ERROR; } } retire: if (qc->max_retired_seqnum && f->retire <= qc->max_retired_seqnum) { /* * Once a sender indicates a Retire Prior To value, smaller values sent * in subsequent NEW_CONNECTION_ID frames have no effect. A receiver * MUST ignore any Retire Prior To fields that do not increase the * largest received Retire Prior To value. */ goto done; } qc->max_retired_seqnum = f->retire; q = ngx_queue_head(&qc->client_ids); while (q != ngx_queue_sentinel(&qc->client_ids)) { cid = ngx_queue_data(q, ngx_quic_client_id_t, queue); q = ngx_queue_next(q); if (cid->seqnum >= f->retire) { continue; } /* this connection id must be retired */ if (ngx_quic_send_retire_connection_id(c, cid->seqnum) != NGX_OK) { return NGX_ERROR; } if (cid->refcnt) { /* we are going to retire client id which is in use */ if (ngx_quic_replace_retired_client_id(c, cid) != NGX_OK) { return NGX_ERROR; } } ngx_quic_unref_client_id(c, cid); } done: if (qc->nclient_ids > qc->tp.active_connection_id_limit) { /* * RFC 9000, 5.1.1. Issuing Connection IDs * * After processing a NEW_CONNECTION_ID frame and * adding and retiring active connection IDs, if the number of active * connection IDs exceeds the value advertised in its * active_connection_id_limit transport parameter, an endpoint MUST * close the connection with an error of type CONNECTION_ID_LIMIT_ERROR. */ qc->error = NGX_QUIC_ERR_CONNECTION_ID_LIMIT_ERROR; qc->error_reason = "too many connection ids received"; return NGX_ERROR; } return NGX_OK; } static ngx_int_t ngx_quic_send_retire_connection_id(ngx_connection_t *c, uint64_t seqnum) { ngx_quic_frame_t *frame; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); frame = ngx_quic_alloc_frame(c); if (frame == NULL) { return NGX_ERROR; } frame->level = ssl_encryption_application; frame->type = NGX_QUIC_FT_RETIRE_CONNECTION_ID; frame->u.retire_cid.sequence_number = seqnum; ngx_quic_queue_frame(qc, frame); /* we are no longer going to use this client id */ return NGX_OK; } static ngx_quic_client_id_t * ngx_quic_alloc_client_id(ngx_connection_t *c, ngx_quic_connection_t *qc) { ngx_queue_t *q; ngx_quic_client_id_t *cid; if (!ngx_queue_empty(&qc->free_client_ids)) { q = ngx_queue_head(&qc->free_client_ids); cid = ngx_queue_data(q, ngx_quic_client_id_t, queue); ngx_queue_remove(&cid->queue); ngx_memzero(cid, sizeof(ngx_quic_client_id_t)); } else { cid = ngx_pcalloc(c->pool, sizeof(ngx_quic_client_id_t)); if (cid == NULL) { return NULL; } } return cid; } ngx_quic_client_id_t * ngx_quic_create_client_id(ngx_connection_t *c, ngx_str_t *id, uint64_t seqnum, u_char *token) { ngx_quic_client_id_t *cid; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); cid = ngx_quic_alloc_client_id(c, qc); if (cid == NULL) { return NULL; } cid->seqnum = seqnum; cid->len = id->len; ngx_memcpy(cid->id, id->data, id->len); if (token) { ngx_memcpy(cid->sr_token, token, NGX_QUIC_SR_TOKEN_LEN); } ngx_queue_insert_tail(&qc->client_ids, &cid->queue); qc->nclient_ids++; if (seqnum > qc->client_seqnum) { qc->client_seqnum = seqnum; } ngx_log_debug5(NGX_LOG_DEBUG_EVENT, c->log, 0, "quic cid #%uL received id:%uz:%xV:%*xs", cid->seqnum, id->len, id, (size_t) NGX_QUIC_SR_TOKEN_LEN, cid->sr_token); return cid; } ngx_quic_client_id_t * ngx_quic_next_client_id(ngx_connection_t *c) { ngx_queue_t *q; ngx_quic_client_id_t *cid; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); for (q = ngx_queue_head(&qc->client_ids); q != ngx_queue_sentinel(&qc->client_ids); q = ngx_queue_next(q)) { cid = ngx_queue_data(q, ngx_quic_client_id_t, queue); if (cid->refcnt == 0) { return cid; } } return NULL; } ngx_quic_client_id_t * ngx_quic_used_client_id(ngx_connection_t *c, ngx_quic_path_t *path) { ngx_queue_t *q; ngx_quic_socket_t *qsock; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); /* best guess: cid used by active path is good for us */ if (qc->socket->path == path) { return qc->socket->cid; } for (q = ngx_queue_head(&qc->sockets); q != ngx_queue_sentinel(&qc->sockets); q = ngx_queue_next(q)) { qsock = ngx_queue_data(q, ngx_quic_socket_t, queue); if (qsock->path && qsock->path == path) { return qsock->cid; } } return NULL; } ngx_int_t ngx_quic_handle_retire_connection_id_frame(ngx_connection_t *c, ngx_quic_retire_cid_frame_t *f) { ngx_quic_path_t *path; ngx_quic_socket_t *qsock, **tmp; ngx_quic_client_id_t *cid; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); qsock = ngx_quic_find_socket(c, f->sequence_number); if (qsock == NULL) { return NGX_OK; } if (qsock->sid.seqnum == qc->socket->sid.seqnum) { tmp = &qc->socket; } else if (qc->backup && qsock->sid.seqnum == qc->backup->sid.seqnum) { tmp = &qc->backup; } else { tmp = NULL; } if (ngx_quic_create_sockets(c) != NGX_OK) { return NGX_ERROR; } if (tmp) { /* replace socket in use (active or backup) */ ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0, "quic %s socket #%uL:%uL:%uL retired", (*tmp) == qc->socket ? "active" : "backup", (*tmp)->sid.seqnum, (*tmp)->cid->seqnum, (*tmp)->path->seqnum); qsock = ngx_quic_get_unconnected_socket(c); if (qsock == NULL) { return NGX_ERROR; } path = (*tmp)->path; cid = (*tmp)->cid; ngx_quic_connect(c, qsock, path, cid); ngx_log_debug5(NGX_LOG_DEBUG_EVENT, c->log, 0, "quic %s socket is now #%uL:%uL:%uL (%s)", (*tmp) == qc->socket ? "active" : "backup", qsock->sid.seqnum, qsock->cid->seqnum, qsock->path->seqnum, ngx_quic_path_state_str(qsock->path)); ngx_quic_close_socket(c, *tmp); /* no longer used */ *tmp = qsock; } return NGX_OK; } ngx_int_t ngx_quic_create_sockets(ngx_connection_t *c) { ngx_uint_t n; ngx_quic_socket_t *qsock; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); n = ngx_min(NGX_QUIC_MAX_SERVER_IDS, qc->ctp.active_connection_id_limit); ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "quic create sockets has:%ui max:%ui", qc->nsockets, n); while (qc->nsockets < n) { qsock = ngx_quic_alloc_socket(c, qc); if (qsock == NULL) { return NGX_ERROR; } if (ngx_quic_listen(c, qc, qsock) != NGX_OK) { return NGX_ERROR; } if (ngx_quic_send_server_id(c, &qsock->sid) != NGX_OK) { return NGX_ERROR; } } return NGX_OK; } static ngx_int_t ngx_quic_send_server_id(ngx_connection_t *c, ngx_quic_server_id_t *sid) { ngx_str_t dcid; ngx_quic_frame_t *frame; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); dcid.len = sid->len; dcid.data = sid->id; frame = ngx_quic_alloc_frame(c); if (frame == NULL) { return NGX_ERROR; } frame->level = ssl_encryption_application; frame->type = NGX_QUIC_FT_NEW_CONNECTION_ID; frame->u.ncid.seqnum = sid->seqnum; frame->u.ncid.retire = 0; frame->u.ncid.len = NGX_QUIC_SERVER_CID_LEN; ngx_memcpy(frame->u.ncid.cid, sid->id, NGX_QUIC_SERVER_CID_LEN); if (ngx_quic_new_sr_token(c, &dcid, qc->conf->sr_token_key, frame->u.ncid.srt) != NGX_OK) { return NGX_ERROR; } ngx_quic_queue_frame(qc, frame); return NGX_OK; } static ngx_int_t ngx_quic_replace_retired_client_id(ngx_connection_t *c, ngx_quic_client_id_t *retired_cid) { ngx_queue_t *q; ngx_quic_socket_t *qsock; ngx_quic_client_id_t *cid; ngx_quic_connection_t *qc; qc = ngx_quic_get_connection(c); for (q = ngx_queue_head(&qc->sockets); q != ngx_queue_sentinel(&qc->sockets); q = ngx_queue_next(q)) { qsock = ngx_queue_data(q, ngx_quic_socket_t, queue); if (qsock->cid == retired_cid) { cid = ngx_quic_next_client_id(c); if (cid == NULL) { return NGX_ERROR; } qsock->cid = cid; cid->refcnt++; ngx_quic_unref_client_id(c, retired_cid); if (retired_cid->refcnt == 0) { return NGX_OK; } } } return NGX_OK; } void ngx_quic_unref_client_id(ngx_connection_t *c, ngx_quic_client_id_t *cid) { ngx_quic_connection_t *qc; cid->refcnt--; if (cid->refcnt) { return; } qc = ngx_quic_get_connection(c); ngx_queue_remove(&cid->queue); ngx_queue_insert_head(&qc->free_client_ids, &cid->queue); qc->nclient_ids--; }