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-rw-r--r--lib/ngtcp2_pkt.c2527
1 files changed, 2527 insertions, 0 deletions
diff --git a/lib/ngtcp2_pkt.c b/lib/ngtcp2_pkt.c
new file mode 100644
index 0000000..f76e07b
--- /dev/null
+++ b/lib/ngtcp2_pkt.c
@@ -0,0 +1,2527 @@
+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2017 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "ngtcp2_pkt.h"
+
+#include <assert.h>
+#include <string.h>
+
+#include "ngtcp2_conv.h"
+#include "ngtcp2_str.h"
+#include "ngtcp2_macro.h"
+#include "ngtcp2_cid.h"
+#include "ngtcp2_mem.h"
+#include "ngtcp2_vec.h"
+#include "ngtcp2_unreachable.h"
+#include "ngtcp2_str.h"
+
+int ngtcp2_pkt_chain_new(ngtcp2_pkt_chain **ppc, const ngtcp2_path *path,
+ const ngtcp2_pkt_info *pi, const uint8_t *pkt,
+ size_t pktlen, size_t dgramlen, ngtcp2_tstamp ts,
+ const ngtcp2_mem *mem) {
+ *ppc = ngtcp2_mem_malloc(mem, sizeof(ngtcp2_pkt_chain) + pktlen);
+ if (*ppc == NULL) {
+ return NGTCP2_ERR_NOMEM;
+ }
+
+ ngtcp2_path_storage_init2(&(*ppc)->path, path);
+ (*ppc)->pi = *pi;
+ (*ppc)->next = NULL;
+ (*ppc)->pkt = (uint8_t *)(*ppc) + sizeof(ngtcp2_pkt_chain);
+ (*ppc)->pktlen = pktlen;
+ (*ppc)->dgramlen = dgramlen;
+ (*ppc)->ts = ts;
+
+ memcpy((*ppc)->pkt, pkt, pktlen);
+
+ return 0;
+}
+
+void ngtcp2_pkt_chain_del(ngtcp2_pkt_chain *pc, const ngtcp2_mem *mem) {
+ ngtcp2_mem_free(mem, pc);
+}
+
+int ngtcp2_pkt_decode_version_cid(ngtcp2_version_cid *dest, const uint8_t *data,
+ size_t datalen, size_t short_dcidlen) {
+ size_t len;
+ uint32_t version;
+ size_t dcidlen, scidlen;
+ int supported_version;
+
+ assert(datalen);
+
+ if (data[0] & NGTCP2_HEADER_FORM_BIT) {
+ /* 1 byte (Header Form, Fixed Bit, Long Packet Type, Type-Specific bits)
+ * 4 bytes Version
+ * 1 byte DCID Length
+ * 1 byte SCID Length
+ */
+ len = 1 + 4 + 1 + 1;
+ if (datalen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ dcidlen = data[5];
+ len += dcidlen;
+ if (datalen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ scidlen = data[5 + 1 + dcidlen];
+ len += scidlen;
+ if (datalen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ ngtcp2_get_uint32(&version, &data[1]);
+
+ supported_version = ngtcp2_is_supported_version(version);
+
+ if (supported_version &&
+ (dcidlen > NGTCP2_MAX_CIDLEN || scidlen > NGTCP2_MAX_CIDLEN)) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ if (version && !supported_version &&
+ datalen < NGTCP2_MAX_UDP_PAYLOAD_SIZE) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ dest->version = version;
+ dest->dcid = &data[6];
+ dest->dcidlen = dcidlen;
+ dest->scid = &data[6 + dcidlen + 1];
+ dest->scidlen = scidlen;
+
+ if (!version) {
+ /* VN */
+ return 0;
+ }
+
+ if (!supported_version) {
+ return NGTCP2_ERR_VERSION_NEGOTIATION;
+ }
+ return 0;
+ }
+
+ assert(short_dcidlen <= NGTCP2_MAX_CIDLEN);
+
+ len = 1 + short_dcidlen;
+ if (datalen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ dest->version = 0;
+ dest->dcid = &data[1];
+ dest->dcidlen = short_dcidlen;
+ dest->scid = NULL;
+ dest->scidlen = 0;
+
+ return 0;
+}
+
+void ngtcp2_pkt_hd_init(ngtcp2_pkt_hd *hd, uint8_t flags, uint8_t type,
+ const ngtcp2_cid *dcid, const ngtcp2_cid *scid,
+ int64_t pkt_num, size_t pkt_numlen, uint32_t version,
+ size_t len) {
+ hd->flags = flags;
+ hd->type = type;
+ if (dcid) {
+ hd->dcid = *dcid;
+ } else {
+ ngtcp2_cid_zero(&hd->dcid);
+ }
+ if (scid) {
+ hd->scid = *scid;
+ } else {
+ ngtcp2_cid_zero(&hd->scid);
+ }
+ hd->pkt_num = pkt_num;
+ hd->token.base = NULL;
+ hd->token.len = 0;
+ hd->pkt_numlen = pkt_numlen;
+ hd->version = version;
+ hd->len = len;
+}
+
+static int has_mask(uint8_t b, uint8_t mask) { return (b & mask) == mask; }
+
+ngtcp2_ssize ngtcp2_pkt_decode_hd_long(ngtcp2_pkt_hd *dest, const uint8_t *pkt,
+ size_t pktlen) {
+ uint8_t type;
+ uint32_t version;
+ size_t dcil, scil;
+ const uint8_t *p;
+ size_t len = 0;
+ size_t n;
+ size_t ntokenlen = 0;
+ const uint8_t *token = NULL;
+ size_t tokenlen = 0;
+ uint64_t vi;
+ uint8_t flags = NGTCP2_PKT_FLAG_LONG_FORM;
+
+ if (pktlen < 5) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ if (!(pkt[0] & NGTCP2_HEADER_FORM_BIT)) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ ngtcp2_get_uint32(&version, &pkt[1]);
+
+ if (version == 0) {
+ type = NGTCP2_PKT_VERSION_NEGOTIATION;
+ /* Version Negotiation is not a long header packet. */
+ flags = NGTCP2_PKT_FLAG_NONE;
+ /* This must be Version Negotiation packet which lacks packet
+ number and payload length fields. */
+ len = 5 + 2;
+ } else {
+ if (!(pkt[0] & NGTCP2_FIXED_BIT_MASK)) {
+ flags |= NGTCP2_PKT_FLAG_FIXED_BIT_CLEAR;
+ }
+
+ type = ngtcp2_pkt_get_type_long(version, pkt[0]);
+ switch (type) {
+ case 0:
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ case NGTCP2_PKT_INITIAL:
+ len = 1 /* Token Length */ + NGTCP2_MIN_LONG_HEADERLEN -
+ 1; /* Cut packet number field */
+ break;
+ case NGTCP2_PKT_RETRY:
+ /* Retry packet does not have packet number and length fields */
+ len = 5 + 2;
+ break;
+ case NGTCP2_PKT_HANDSHAKE:
+ case NGTCP2_PKT_0RTT:
+ len = NGTCP2_MIN_LONG_HEADERLEN - 1; /* Cut packet number field */
+ break;
+ default:
+ /* Unreachable */
+ ngtcp2_unreachable();
+ }
+ }
+
+ if (pktlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ p = &pkt[5];
+ dcil = *p;
+ if (dcil > NGTCP2_MAX_CIDLEN) {
+ /* QUIC v1 implementation never expect to receive CID length more
+ than NGTCP2_MAX_CIDLEN. */
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ len += dcil;
+
+ if (pktlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ p += 1 + dcil;
+ scil = *p;
+ if (scil > NGTCP2_MAX_CIDLEN) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ len += scil;
+
+ if (pktlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ p += 1 + scil;
+
+ if (type == NGTCP2_PKT_INITIAL) {
+ /* Token Length */
+ ntokenlen = ngtcp2_get_uvarintlen(p);
+ len += ntokenlen - 1;
+
+ if (pktlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (pktlen - len < vi) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ tokenlen = (size_t)vi;
+ len += tokenlen;
+
+ if (tokenlen) {
+ token = p;
+ }
+
+ p += tokenlen;
+ }
+
+ switch (type) {
+ case NGTCP2_PKT_RETRY:
+ break;
+ default:
+ if (!(flags & NGTCP2_PKT_FLAG_LONG_FORM)) {
+ assert(type == NGTCP2_PKT_VERSION_NEGOTIATION);
+ /* Version Negotiation is not a long header packet. */
+ break;
+ }
+
+ /* Length */
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (pktlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ }
+
+ dest->flags = flags;
+ dest->type = type;
+ dest->version = version;
+ dest->pkt_num = 0;
+ dest->pkt_numlen = 0;
+
+ p = &pkt[6];
+ ngtcp2_cid_init(&dest->dcid, p, dcil);
+ p += dcil + 1;
+ ngtcp2_cid_init(&dest->scid, p, scil);
+ p += scil;
+
+ dest->token.base = (uint8_t *)token;
+ dest->token.len = tokenlen;
+ p += ntokenlen + tokenlen;
+
+ switch (type) {
+ case NGTCP2_PKT_RETRY:
+ dest->len = 0;
+ break;
+ default:
+ if (!(flags & NGTCP2_PKT_FLAG_LONG_FORM)) {
+ assert(type == NGTCP2_PKT_VERSION_NEGOTIATION);
+ /* Version Negotiation is not a long header packet. */
+ dest->len = 0;
+ break;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (vi > SIZE_MAX) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ dest->len = (size_t)vi;
+ }
+
+ assert((size_t)(p - pkt) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_hd_short(ngtcp2_pkt_hd *dest, const uint8_t *pkt,
+ size_t pktlen, size_t dcidlen) {
+ size_t len = 1 + dcidlen;
+ const uint8_t *p = pkt;
+ uint8_t flags = NGTCP2_PKT_FLAG_NONE;
+
+ assert(dcidlen <= NGTCP2_MAX_CIDLEN);
+
+ if (pktlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ if (pkt[0] & NGTCP2_HEADER_FORM_BIT) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ if (!(pkt[0] & NGTCP2_FIXED_BIT_MASK)) {
+ flags |= NGTCP2_PKT_FLAG_FIXED_BIT_CLEAR;
+ }
+
+ p = &pkt[1];
+
+ dest->type = NGTCP2_PKT_1RTT;
+
+ ngtcp2_cid_init(&dest->dcid, p, dcidlen);
+ p += dcidlen;
+
+ /* Set 0 to SCID so that we don't accidentally reference it and gets
+ garbage. */
+ ngtcp2_cid_zero(&dest->scid);
+
+ dest->flags = flags;
+ dest->version = 0;
+ dest->len = 0;
+ dest->pkt_num = 0;
+ dest->pkt_numlen = 0;
+ dest->token.base = NULL;
+ dest->token.len = 0;
+
+ assert((size_t)(p - pkt) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_hd_long(uint8_t *out, size_t outlen,
+ const ngtcp2_pkt_hd *hd) {
+ uint8_t *p;
+ size_t len = NGTCP2_MIN_LONG_HEADERLEN + hd->dcid.datalen + hd->scid.datalen -
+ 2; /* NGTCP2_MIN_LONG_HEADERLEN includes 1 byte for
+ len and 1 byte for packet number. */
+
+ if (hd->type != NGTCP2_PKT_RETRY) {
+ len += NGTCP2_PKT_LENGTHLEN /* Length */ + hd->pkt_numlen;
+ }
+
+ if (hd->type == NGTCP2_PKT_INITIAL) {
+ len += ngtcp2_put_uvarintlen(hd->token.len) + hd->token.len;
+ }
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p = (uint8_t)(NGTCP2_HEADER_FORM_BIT |
+ (ngtcp2_pkt_versioned_type(hd->version, hd->type) << 4) |
+ (uint8_t)(hd->pkt_numlen - 1));
+ if (!(hd->flags & NGTCP2_PKT_FLAG_FIXED_BIT_CLEAR)) {
+ *p |= NGTCP2_FIXED_BIT_MASK;
+ }
+
+ ++p;
+
+ p = ngtcp2_put_uint32be(p, hd->version);
+ *p++ = (uint8_t)hd->dcid.datalen;
+ if (hd->dcid.datalen) {
+ p = ngtcp2_cpymem(p, hd->dcid.data, hd->dcid.datalen);
+ }
+ *p++ = (uint8_t)hd->scid.datalen;
+ if (hd->scid.datalen) {
+ p = ngtcp2_cpymem(p, hd->scid.data, hd->scid.datalen);
+ }
+
+ if (hd->type == NGTCP2_PKT_INITIAL) {
+ p = ngtcp2_put_uvarint(p, hd->token.len);
+ if (hd->token.len) {
+ p = ngtcp2_cpymem(p, hd->token.base, hd->token.len);
+ }
+ }
+
+ if (hd->type != NGTCP2_PKT_RETRY) {
+ p = ngtcp2_put_uvarint30(p, (uint32_t)hd->len);
+ p = ngtcp2_put_pkt_num(p, hd->pkt_num, hd->pkt_numlen);
+ }
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_hd_short(uint8_t *out, size_t outlen,
+ const ngtcp2_pkt_hd *hd) {
+ uint8_t *p;
+ size_t len = 1 + hd->dcid.datalen + hd->pkt_numlen;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p = (uint8_t)(hd->pkt_numlen - 1);
+ if (!(hd->flags & NGTCP2_PKT_FLAG_FIXED_BIT_CLEAR)) {
+ *p |= NGTCP2_FIXED_BIT_MASK;
+ }
+ if (hd->flags & NGTCP2_PKT_FLAG_KEY_PHASE) {
+ *p |= NGTCP2_SHORT_KEY_PHASE_BIT;
+ }
+
+ ++p;
+
+ if (hd->dcid.datalen) {
+ p = ngtcp2_cpymem(p, hd->dcid.data, hd->dcid.datalen);
+ }
+
+ p = ngtcp2_put_pkt_num(p, hd->pkt_num, hd->pkt_numlen);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_frame(ngtcp2_frame *dest, const uint8_t *payload,
+ size_t payloadlen) {
+ uint8_t type;
+
+ if (payloadlen == 0) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ type = payload[0];
+
+ switch (type) {
+ case NGTCP2_FRAME_PADDING:
+ return ngtcp2_pkt_decode_padding_frame(&dest->padding, payload, payloadlen);
+ case NGTCP2_FRAME_RESET_STREAM:
+ return ngtcp2_pkt_decode_reset_stream_frame(&dest->reset_stream, payload,
+ payloadlen);
+ case NGTCP2_FRAME_CONNECTION_CLOSE:
+ case NGTCP2_FRAME_CONNECTION_CLOSE_APP:
+ return ngtcp2_pkt_decode_connection_close_frame(&dest->connection_close,
+ payload, payloadlen);
+ case NGTCP2_FRAME_MAX_DATA:
+ return ngtcp2_pkt_decode_max_data_frame(&dest->max_data, payload,
+ payloadlen);
+ case NGTCP2_FRAME_MAX_STREAM_DATA:
+ return ngtcp2_pkt_decode_max_stream_data_frame(&dest->max_stream_data,
+ payload, payloadlen);
+ case NGTCP2_FRAME_MAX_STREAMS_BIDI:
+ case NGTCP2_FRAME_MAX_STREAMS_UNI:
+ return ngtcp2_pkt_decode_max_streams_frame(&dest->max_streams, payload,
+ payloadlen);
+ case NGTCP2_FRAME_PING:
+ return ngtcp2_pkt_decode_ping_frame(&dest->ping, payload, payloadlen);
+ case NGTCP2_FRAME_DATA_BLOCKED:
+ return ngtcp2_pkt_decode_data_blocked_frame(&dest->data_blocked, payload,
+ payloadlen);
+ case NGTCP2_FRAME_STREAM_DATA_BLOCKED:
+ return ngtcp2_pkt_decode_stream_data_blocked_frame(
+ &dest->stream_data_blocked, payload, payloadlen);
+ case NGTCP2_FRAME_STREAMS_BLOCKED_BIDI:
+ case NGTCP2_FRAME_STREAMS_BLOCKED_UNI:
+ return ngtcp2_pkt_decode_streams_blocked_frame(&dest->streams_blocked,
+ payload, payloadlen);
+ case NGTCP2_FRAME_NEW_CONNECTION_ID:
+ return ngtcp2_pkt_decode_new_connection_id_frame(&dest->new_connection_id,
+ payload, payloadlen);
+ case NGTCP2_FRAME_STOP_SENDING:
+ return ngtcp2_pkt_decode_stop_sending_frame(&dest->stop_sending, payload,
+ payloadlen);
+ case NGTCP2_FRAME_ACK:
+ case NGTCP2_FRAME_ACK_ECN:
+ return ngtcp2_pkt_decode_ack_frame(&dest->ack, payload, payloadlen);
+ case NGTCP2_FRAME_PATH_CHALLENGE:
+ return ngtcp2_pkt_decode_path_challenge_frame(&dest->path_challenge,
+ payload, payloadlen);
+ case NGTCP2_FRAME_PATH_RESPONSE:
+ return ngtcp2_pkt_decode_path_response_frame(&dest->path_response, payload,
+ payloadlen);
+ case NGTCP2_FRAME_CRYPTO:
+ return ngtcp2_pkt_decode_crypto_frame(&dest->crypto, payload, payloadlen);
+ case NGTCP2_FRAME_NEW_TOKEN:
+ return ngtcp2_pkt_decode_new_token_frame(&dest->new_token, payload,
+ payloadlen);
+ case NGTCP2_FRAME_RETIRE_CONNECTION_ID:
+ return ngtcp2_pkt_decode_retire_connection_id_frame(
+ &dest->retire_connection_id, payload, payloadlen);
+ case NGTCP2_FRAME_HANDSHAKE_DONE:
+ return ngtcp2_pkt_decode_handshake_done_frame(&dest->handshake_done,
+ payload, payloadlen);
+ case NGTCP2_FRAME_DATAGRAM:
+ case NGTCP2_FRAME_DATAGRAM_LEN:
+ return ngtcp2_pkt_decode_datagram_frame(&dest->datagram, payload,
+ payloadlen);
+ default:
+ if (has_mask(type, NGTCP2_FRAME_STREAM)) {
+ return ngtcp2_pkt_decode_stream_frame(&dest->stream, payload, payloadlen);
+ }
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_stream_frame(ngtcp2_stream *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ uint8_t type;
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t datalen;
+ size_t ndatalen = 0;
+ size_t n;
+ uint64_t vi;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ type = payload[0];
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ if (type & NGTCP2_STREAM_OFF_BIT) {
+ ++len;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+ }
+
+ if (type & NGTCP2_STREAM_LEN_BIT) {
+ ++len;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ ndatalen = ngtcp2_get_uvarintlen(p);
+ len += ndatalen - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ /* p = */ ngtcp2_get_uvarint(&vi, p);
+ if (payloadlen - len < vi) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+ datalen = (size_t)vi;
+ len += datalen;
+ } else {
+ len = payloadlen;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_STREAM;
+ dest->flags = (uint8_t)(type & ~NGTCP2_FRAME_STREAM);
+ dest->fin = (type & NGTCP2_STREAM_FIN_BIT) != 0;
+ p = ngtcp2_get_varint(&dest->stream_id, p);
+
+ if (type & NGTCP2_STREAM_OFF_BIT) {
+ p = ngtcp2_get_uvarint(&dest->offset, p);
+ } else {
+ dest->offset = 0;
+ }
+
+ if (type & NGTCP2_STREAM_LEN_BIT) {
+ p += ndatalen;
+ } else {
+ datalen = payloadlen - (size_t)(p - payload);
+ }
+
+ if (datalen) {
+ dest->data[0].len = datalen;
+ dest->data[0].base = (uint8_t *)p;
+ dest->datacnt = 1;
+ p += datalen;
+ } else {
+ dest->datacnt = 0;
+ }
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_ack_frame(ngtcp2_ack *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t rangecnt, max_rangecnt;
+ size_t nrangecnt;
+ size_t len = 1 + 1 + 1 + 1 + 1;
+ const uint8_t *p;
+ size_t i, j;
+ ngtcp2_ack_range *range;
+ size_t n;
+ uint8_t type;
+ uint64_t vi;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ type = payload[0];
+
+ p = payload + 1;
+
+ /* Largest Acknowledged */
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ /* ACK Delay */
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ /* ACK Range Count */
+ nrangecnt = ngtcp2_get_uvarintlen(p);
+ len += nrangecnt - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (vi > SIZE_MAX / (1 + 1) || payloadlen - len < vi * (1 + 1)) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ rangecnt = (size_t)vi;
+ len += rangecnt * (1 + 1);
+
+ /* First ACK Range */
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ for (i = 0; i < rangecnt; ++i) {
+ /* Gap, and Additional ACK Range */
+ for (j = 0; j < 2; ++j) {
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+ }
+ }
+
+ if (type == NGTCP2_FRAME_ACK_ECN) {
+ len += 3;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ for (i = 0; i < 3; ++i) {
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+ }
+ }
+
+ /* TODO We might not decode all ranges. It could be very large. */
+ max_rangecnt = ngtcp2_min(NGTCP2_MAX_ACK_RANGES, rangecnt);
+
+ p = payload + 1;
+
+ dest->type = type;
+ p = ngtcp2_get_varint(&dest->largest_ack, p);
+ p = ngtcp2_get_uvarint(&dest->ack_delay, p);
+ /* This value will be assigned in the upper layer. */
+ dest->ack_delay_unscaled = 0;
+ dest->rangecnt = max_rangecnt;
+ p += nrangecnt;
+ p = ngtcp2_get_uvarint(&dest->first_ack_range, p);
+
+ for (i = 0; i < max_rangecnt; ++i) {
+ range = &dest->ranges[i];
+ p = ngtcp2_get_uvarint(&range->gap, p);
+ p = ngtcp2_get_uvarint(&range->len, p);
+ }
+ for (i = max_rangecnt; i < rangecnt; ++i) {
+ p += ngtcp2_get_uvarintlen(p);
+ p += ngtcp2_get_uvarintlen(p);
+ }
+
+ if (type == NGTCP2_FRAME_ACK_ECN) {
+ p = ngtcp2_get_uvarint(&dest->ecn.ect0, p);
+ p = ngtcp2_get_uvarint(&dest->ecn.ect1, p);
+ p = ngtcp2_get_uvarint(&dest->ecn.ce, p);
+ }
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_padding_frame(ngtcp2_padding *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ const uint8_t *p, *ep;
+
+ assert(payloadlen > 0);
+
+ p = payload + 1;
+ ep = payload + payloadlen;
+
+ for (; p != ep && *p == NGTCP2_FRAME_PADDING; ++p)
+ ;
+
+ dest->type = NGTCP2_FRAME_PADDING;
+ dest->len = (size_t)(p - payload);
+
+ return (ngtcp2_ssize)dest->len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_reset_stream_frame(ngtcp2_reset_stream *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1 + 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+ p += n;
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+ p += n;
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_RESET_STREAM;
+ p = ngtcp2_get_varint(&dest->stream_id, p);
+ p = ngtcp2_get_uvarint(&dest->app_error_code, p);
+ p = ngtcp2_get_uvarint(&dest->final_size, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_connection_close_frame(
+ ngtcp2_connection_close *dest, const uint8_t *payload, size_t payloadlen) {
+ size_t len = 1 + 1 + 1;
+ const uint8_t *p;
+ size_t reasonlen;
+ size_t nreasonlen;
+ size_t n;
+ uint8_t type;
+ uint64_t vi;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ type = payload[0];
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ if (type == NGTCP2_FRAME_CONNECTION_CLOSE) {
+ ++len;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+ }
+
+ nreasonlen = ngtcp2_get_uvarintlen(p);
+ len += nreasonlen - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (payloadlen - len < vi) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+ reasonlen = (size_t)vi;
+ len += reasonlen;
+
+ p = payload + 1;
+
+ dest->type = type;
+ p = ngtcp2_get_uvarint(&dest->error_code, p);
+ if (type == NGTCP2_FRAME_CONNECTION_CLOSE) {
+ p = ngtcp2_get_uvarint(&dest->frame_type, p);
+ } else {
+ dest->frame_type = 0;
+ }
+ dest->reasonlen = reasonlen;
+ p += nreasonlen;
+ if (reasonlen == 0) {
+ dest->reason = NULL;
+ } else {
+ dest->reason = (uint8_t *)p;
+ p += reasonlen;
+ }
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_max_data_frame(ngtcp2_max_data *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ dest->type = NGTCP2_FRAME_MAX_DATA;
+ p = ngtcp2_get_uvarint(&dest->max_data, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_max_stream_data_frame(
+ ngtcp2_max_stream_data *dest, const uint8_t *payload, size_t payloadlen) {
+ size_t len = 1 + 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_MAX_STREAM_DATA;
+ p = ngtcp2_get_varint(&dest->stream_id, p);
+ p = ngtcp2_get_uvarint(&dest->max_stream_data, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_max_streams_frame(ngtcp2_max_streams *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ dest->type = payload[0];
+ p = ngtcp2_get_uvarint(&dest->max_streams, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_ping_frame(ngtcp2_ping *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ (void)payload;
+ (void)payloadlen;
+
+ dest->type = NGTCP2_FRAME_PING;
+ return 1;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_data_blocked_frame(ngtcp2_data_blocked *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ dest->type = NGTCP2_FRAME_DATA_BLOCKED;
+ p = ngtcp2_get_uvarint(&dest->offset, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_decode_stream_data_blocked_frame(ngtcp2_stream_data_blocked *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_STREAM_DATA_BLOCKED;
+ p = ngtcp2_get_varint(&dest->stream_id, p);
+ p = ngtcp2_get_uvarint(&dest->offset, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_streams_blocked_frame(
+ ngtcp2_streams_blocked *dest, const uint8_t *payload, size_t payloadlen) {
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ dest->type = payload[0];
+ p = ngtcp2_get_uvarint(&dest->max_streams, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_new_connection_id_frame(
+ ngtcp2_new_connection_id *dest, const uint8_t *payload, size_t payloadlen) {
+ size_t len = 1 + 1 + 1 + 1 + 16;
+ const uint8_t *p;
+ size_t n;
+ size_t cil;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ cil = *p;
+ if (cil < NGTCP2_MIN_CIDLEN || cil > NGTCP2_MAX_CIDLEN) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ len += cil;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_NEW_CONNECTION_ID;
+ p = ngtcp2_get_uvarint(&dest->seq, p);
+ p = ngtcp2_get_uvarint(&dest->retire_prior_to, p);
+ ++p;
+ ngtcp2_cid_init(&dest->cid, p, cil);
+ p += cil;
+ p = ngtcp2_get_bytes(dest->stateless_reset_token, p,
+ NGTCP2_STATELESS_RESET_TOKENLEN);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_stop_sending_frame(ngtcp2_stop_sending *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+ p += n;
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_STOP_SENDING;
+ p = ngtcp2_get_varint(&dest->stream_id, p);
+ p = ngtcp2_get_uvarint(&dest->app_error_code, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_path_challenge_frame(ngtcp2_path_challenge *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 8;
+ const uint8_t *p;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_PATH_CHALLENGE;
+ ngtcp2_cpymem(dest->data, p, sizeof(dest->data));
+ p += sizeof(dest->data);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_path_response_frame(ngtcp2_path_response *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 8;
+ const uint8_t *p;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_PATH_RESPONSE;
+ ngtcp2_cpymem(dest->data, p, sizeof(dest->data));
+ p += sizeof(dest->data);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_crypto_frame(ngtcp2_crypto *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1 + 1;
+ const uint8_t *p;
+ size_t datalen;
+ size_t ndatalen;
+ size_t n;
+ uint64_t vi;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p += n;
+
+ ndatalen = ngtcp2_get_uvarintlen(p);
+ len += ndatalen - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (payloadlen - len < vi) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ datalen = (size_t)vi;
+ len += datalen;
+
+ p = payload + 1;
+
+ dest->type = NGTCP2_FRAME_CRYPTO;
+ p = ngtcp2_get_uvarint(&dest->offset, p);
+ dest->data[0].len = datalen;
+ p += ndatalen;
+ if (dest->data[0].len) {
+ dest->data[0].base = (uint8_t *)p;
+ p += dest->data[0].len;
+ dest->datacnt = 1;
+ } else {
+ dest->data[0].base = NULL;
+ dest->datacnt = 0;
+ }
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_new_token_frame(ngtcp2_new_token *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t n;
+ size_t datalen;
+ uint64_t vi;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (payloadlen - len < vi) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+ datalen = (size_t)vi;
+ len += datalen;
+
+ dest->type = NGTCP2_FRAME_NEW_TOKEN;
+ dest->token.len = datalen;
+ dest->token.base = (uint8_t *)p;
+ p += dest->token.len;
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_decode_retire_connection_id_frame(ngtcp2_retire_connection_id *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1 + 1;
+ const uint8_t *p;
+ size_t n;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = payload + 1;
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ dest->type = NGTCP2_FRAME_RETIRE_CONNECTION_ID;
+ p = ngtcp2_get_uvarint(&dest->seq, p);
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_handshake_done_frame(ngtcp2_handshake_done *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ (void)payload;
+ (void)payloadlen;
+
+ dest->type = NGTCP2_FRAME_HANDSHAKE_DONE;
+ return 1;
+}
+
+ngtcp2_ssize ngtcp2_pkt_decode_datagram_frame(ngtcp2_datagram *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = 1;
+ const uint8_t *p;
+ uint8_t type;
+ size_t datalen;
+ size_t n;
+ uint64_t vi;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ type = payload[0];
+
+ p = payload + 1;
+
+ switch (type) {
+ case NGTCP2_FRAME_DATAGRAM:
+ datalen = payloadlen - 1;
+ len = payloadlen;
+ break;
+ case NGTCP2_FRAME_DATAGRAM_LEN:
+ ++len;
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ n = ngtcp2_get_uvarintlen(p);
+ len += n - 1;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ p = ngtcp2_get_uvarint(&vi, p);
+ if (payloadlen - len < vi) {
+ return NGTCP2_ERR_FRAME_ENCODING;
+ }
+
+ datalen = (size_t)vi;
+ len += datalen;
+ break;
+ default:
+ ngtcp2_unreachable();
+ }
+
+ dest->type = type;
+
+ if (datalen == 0) {
+ dest->datacnt = 0;
+ dest->data = NULL;
+ } else {
+ dest->datacnt = 1;
+ dest->data = dest->rdata;
+ dest->rdata[0].len = datalen;
+
+ dest->rdata[0].base = (uint8_t *)p;
+ p += datalen;
+ }
+
+ assert((size_t)(p - payload) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_frame(uint8_t *out, size_t outlen,
+ ngtcp2_frame *fr) {
+ switch (fr->type) {
+ case NGTCP2_FRAME_STREAM:
+ return ngtcp2_pkt_encode_stream_frame(out, outlen, &fr->stream);
+ case NGTCP2_FRAME_ACK:
+ case NGTCP2_FRAME_ACK_ECN:
+ return ngtcp2_pkt_encode_ack_frame(out, outlen, &fr->ack);
+ case NGTCP2_FRAME_PADDING:
+ return ngtcp2_pkt_encode_padding_frame(out, outlen, &fr->padding);
+ case NGTCP2_FRAME_RESET_STREAM:
+ return ngtcp2_pkt_encode_reset_stream_frame(out, outlen, &fr->reset_stream);
+ case NGTCP2_FRAME_CONNECTION_CLOSE:
+ case NGTCP2_FRAME_CONNECTION_CLOSE_APP:
+ return ngtcp2_pkt_encode_connection_close_frame(out, outlen,
+ &fr->connection_close);
+ case NGTCP2_FRAME_MAX_DATA:
+ return ngtcp2_pkt_encode_max_data_frame(out, outlen, &fr->max_data);
+ case NGTCP2_FRAME_MAX_STREAM_DATA:
+ return ngtcp2_pkt_encode_max_stream_data_frame(out, outlen,
+ &fr->max_stream_data);
+ case NGTCP2_FRAME_MAX_STREAMS_BIDI:
+ case NGTCP2_FRAME_MAX_STREAMS_UNI:
+ return ngtcp2_pkt_encode_max_streams_frame(out, outlen, &fr->max_streams);
+ case NGTCP2_FRAME_PING:
+ return ngtcp2_pkt_encode_ping_frame(out, outlen, &fr->ping);
+ case NGTCP2_FRAME_DATA_BLOCKED:
+ return ngtcp2_pkt_encode_data_blocked_frame(out, outlen, &fr->data_blocked);
+ case NGTCP2_FRAME_STREAM_DATA_BLOCKED:
+ return ngtcp2_pkt_encode_stream_data_blocked_frame(
+ out, outlen, &fr->stream_data_blocked);
+ case NGTCP2_FRAME_STREAMS_BLOCKED_BIDI:
+ case NGTCP2_FRAME_STREAMS_BLOCKED_UNI:
+ return ngtcp2_pkt_encode_streams_blocked_frame(out, outlen,
+ &fr->streams_blocked);
+ case NGTCP2_FRAME_NEW_CONNECTION_ID:
+ return ngtcp2_pkt_encode_new_connection_id_frame(out, outlen,
+ &fr->new_connection_id);
+ case NGTCP2_FRAME_STOP_SENDING:
+ return ngtcp2_pkt_encode_stop_sending_frame(out, outlen, &fr->stop_sending);
+ case NGTCP2_FRAME_PATH_CHALLENGE:
+ return ngtcp2_pkt_encode_path_challenge_frame(out, outlen,
+ &fr->path_challenge);
+ case NGTCP2_FRAME_PATH_RESPONSE:
+ return ngtcp2_pkt_encode_path_response_frame(out, outlen,
+ &fr->path_response);
+ case NGTCP2_FRAME_CRYPTO:
+ return ngtcp2_pkt_encode_crypto_frame(out, outlen, &fr->crypto);
+ case NGTCP2_FRAME_NEW_TOKEN:
+ return ngtcp2_pkt_encode_new_token_frame(out, outlen, &fr->new_token);
+ case NGTCP2_FRAME_RETIRE_CONNECTION_ID:
+ return ngtcp2_pkt_encode_retire_connection_id_frame(
+ out, outlen, &fr->retire_connection_id);
+ case NGTCP2_FRAME_HANDSHAKE_DONE:
+ return ngtcp2_pkt_encode_handshake_done_frame(out, outlen,
+ &fr->handshake_done);
+ case NGTCP2_FRAME_DATAGRAM:
+ case NGTCP2_FRAME_DATAGRAM_LEN:
+ return ngtcp2_pkt_encode_datagram_frame(out, outlen, &fr->datagram);
+ default:
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_stream_frame(uint8_t *out, size_t outlen,
+ ngtcp2_stream *fr) {
+ size_t len = 1;
+ uint8_t flags = NGTCP2_STREAM_LEN_BIT;
+ uint8_t *p;
+ size_t i;
+ size_t datalen = 0;
+
+ if (fr->fin) {
+ flags |= NGTCP2_STREAM_FIN_BIT;
+ }
+
+ if (fr->offset) {
+ flags |= NGTCP2_STREAM_OFF_BIT;
+ len += ngtcp2_put_uvarintlen(fr->offset);
+ }
+
+ len += ngtcp2_put_uvarintlen((uint64_t)fr->stream_id);
+
+ for (i = 0; i < fr->datacnt; ++i) {
+ datalen += fr->data[i].len;
+ }
+
+ len += ngtcp2_put_uvarintlen(datalen);
+ len += datalen;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = flags | NGTCP2_FRAME_STREAM;
+
+ fr->flags = flags;
+
+ p = ngtcp2_put_uvarint(p, (uint64_t)fr->stream_id);
+
+ if (fr->offset) {
+ p = ngtcp2_put_uvarint(p, fr->offset);
+ }
+
+ p = ngtcp2_put_uvarint(p, datalen);
+
+ for (i = 0; i < fr->datacnt; ++i) {
+ assert(fr->data[i].len);
+ assert(fr->data[i].base);
+ p = ngtcp2_cpymem(p, fr->data[i].base, fr->data[i].len);
+ }
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_ack_frame(uint8_t *out, size_t outlen,
+ ngtcp2_ack *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen((uint64_t)fr->largest_ack) +
+ ngtcp2_put_uvarintlen(fr->ack_delay) +
+ ngtcp2_put_uvarintlen(fr->rangecnt) +
+ ngtcp2_put_uvarintlen(fr->first_ack_range);
+ uint8_t *p;
+ size_t i;
+ const ngtcp2_ack_range *range;
+
+ for (i = 0; i < fr->rangecnt; ++i) {
+ range = &fr->ranges[i];
+ len += ngtcp2_put_uvarintlen(range->gap);
+ len += ngtcp2_put_uvarintlen(range->len);
+ }
+
+ if (fr->type == NGTCP2_FRAME_ACK_ECN) {
+ len += ngtcp2_put_uvarintlen(fr->ecn.ect0) +
+ ngtcp2_put_uvarintlen(fr->ecn.ect1) +
+ ngtcp2_put_uvarintlen(fr->ecn.ce);
+ }
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = fr->type;
+ p = ngtcp2_put_uvarint(p, (uint64_t)fr->largest_ack);
+ p = ngtcp2_put_uvarint(p, fr->ack_delay);
+ p = ngtcp2_put_uvarint(p, fr->rangecnt);
+ p = ngtcp2_put_uvarint(p, fr->first_ack_range);
+
+ for (i = 0; i < fr->rangecnt; ++i) {
+ range = &fr->ranges[i];
+ p = ngtcp2_put_uvarint(p, range->gap);
+ p = ngtcp2_put_uvarint(p, range->len);
+ }
+
+ if (fr->type == NGTCP2_FRAME_ACK_ECN) {
+ p = ngtcp2_put_uvarint(p, fr->ecn.ect0);
+ p = ngtcp2_put_uvarint(p, fr->ecn.ect1);
+ p = ngtcp2_put_uvarint(p, fr->ecn.ce);
+ }
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_padding_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_padding *fr) {
+ if (outlen < fr->len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ memset(out, 0, fr->len);
+
+ return (ngtcp2_ssize)fr->len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_reset_stream_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_reset_stream *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen((uint64_t)fr->stream_id) +
+ ngtcp2_put_uvarintlen(fr->app_error_code) +
+ ngtcp2_put_uvarintlen(fr->final_size);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_RESET_STREAM;
+ p = ngtcp2_put_uvarint(p, (uint64_t)fr->stream_id);
+ p = ngtcp2_put_uvarint(p, fr->app_error_code);
+ p = ngtcp2_put_uvarint(p, fr->final_size);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_connection_close_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_connection_close *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->error_code) +
+ (fr->type == NGTCP2_FRAME_CONNECTION_CLOSE
+ ? ngtcp2_put_uvarintlen(fr->frame_type)
+ : 0) +
+ ngtcp2_put_uvarintlen(fr->reasonlen) + fr->reasonlen;
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = fr->type;
+ p = ngtcp2_put_uvarint(p, fr->error_code);
+ if (fr->type == NGTCP2_FRAME_CONNECTION_CLOSE) {
+ p = ngtcp2_put_uvarint(p, fr->frame_type);
+ }
+ p = ngtcp2_put_uvarint(p, fr->reasonlen);
+ if (fr->reasonlen) {
+ p = ngtcp2_cpymem(p, fr->reason, fr->reasonlen);
+ }
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_max_data_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_max_data *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->max_data);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_MAX_DATA;
+ p = ngtcp2_put_uvarint(p, fr->max_data);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_max_stream_data_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_max_stream_data *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen((uint64_t)fr->stream_id) +
+ ngtcp2_put_uvarintlen(fr->max_stream_data);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_MAX_STREAM_DATA;
+ p = ngtcp2_put_uvarint(p, (uint64_t)fr->stream_id);
+ p = ngtcp2_put_uvarint(p, fr->max_stream_data);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_max_streams_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_max_streams *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->max_streams);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = fr->type;
+ p = ngtcp2_put_uvarint(p, fr->max_streams);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_ping_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_ping *fr) {
+ (void)fr;
+
+ if (outlen < 1) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ *out++ = NGTCP2_FRAME_PING;
+
+ return 1;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_data_blocked_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_data_blocked *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->offset);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_DATA_BLOCKED;
+ p = ngtcp2_put_uvarint(p, fr->offset);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_stream_data_blocked_frame(
+ uint8_t *out, size_t outlen, const ngtcp2_stream_data_blocked *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen((uint64_t)fr->stream_id) +
+ ngtcp2_put_uvarintlen(fr->offset);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_STREAM_DATA_BLOCKED;
+ p = ngtcp2_put_uvarint(p, (uint64_t)fr->stream_id);
+ p = ngtcp2_put_uvarint(p, fr->offset);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_streams_blocked_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_streams_blocked *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->max_streams);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = fr->type;
+ p = ngtcp2_put_uvarint(p, fr->max_streams);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_new_connection_id_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_new_connection_id *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->seq) +
+ ngtcp2_put_uvarintlen(fr->retire_prior_to) + 1 +
+ fr->cid.datalen + NGTCP2_STATELESS_RESET_TOKENLEN;
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_NEW_CONNECTION_ID;
+ p = ngtcp2_put_uvarint(p, fr->seq);
+ p = ngtcp2_put_uvarint(p, fr->retire_prior_to);
+ *p++ = (uint8_t)fr->cid.datalen;
+ p = ngtcp2_cpymem(p, fr->cid.data, fr->cid.datalen);
+ p = ngtcp2_cpymem(p, fr->stateless_reset_token,
+ NGTCP2_STATELESS_RESET_TOKENLEN);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_stop_sending_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_stop_sending *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen((uint64_t)fr->stream_id) +
+ ngtcp2_put_uvarintlen(fr->app_error_code);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_STOP_SENDING;
+ p = ngtcp2_put_uvarint(p, (uint64_t)fr->stream_id);
+ p = ngtcp2_put_uvarint(p, fr->app_error_code);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_path_challenge_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_path_challenge *fr) {
+ size_t len = 1 + 8;
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_PATH_CHALLENGE;
+ p = ngtcp2_cpymem(p, fr->data, sizeof(fr->data));
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_path_response_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_path_response *fr) {
+ size_t len = 1 + 8;
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_PATH_RESPONSE;
+ p = ngtcp2_cpymem(p, fr->data, sizeof(fr->data));
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_crypto_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_crypto *fr) {
+ size_t len = 1;
+ uint8_t *p;
+ size_t i;
+ size_t datalen = 0;
+
+ len += ngtcp2_put_uvarintlen(fr->offset);
+
+ for (i = 0; i < fr->datacnt; ++i) {
+ datalen += fr->data[i].len;
+ }
+
+ len += ngtcp2_put_uvarintlen(datalen);
+ len += datalen;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_CRYPTO;
+
+ p = ngtcp2_put_uvarint(p, fr->offset);
+ p = ngtcp2_put_uvarint(p, datalen);
+
+ for (i = 0; i < fr->datacnt; ++i) {
+ assert(fr->data[i].base);
+ p = ngtcp2_cpymem(p, fr->data[i].base, fr->data[i].len);
+ }
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_new_token_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_new_token *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->token.len) + fr->token.len;
+ uint8_t *p;
+
+ assert(fr->token.len);
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_NEW_TOKEN;
+
+ p = ngtcp2_put_uvarint(p, fr->token.len);
+ p = ngtcp2_cpymem(p, fr->token.base, fr->token.len);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_retire_connection_id_frame(
+ uint8_t *out, size_t outlen, const ngtcp2_retire_connection_id *fr) {
+ size_t len = 1 + ngtcp2_put_uvarintlen(fr->seq);
+ uint8_t *p;
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = NGTCP2_FRAME_RETIRE_CONNECTION_ID;
+
+ p = ngtcp2_put_uvarint(p, fr->seq);
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_encode_handshake_done_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_handshake_done *fr) {
+ (void)fr;
+
+ if (outlen < 1) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ *out++ = NGTCP2_FRAME_HANDSHAKE_DONE;
+
+ return 1;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_datagram_frame(uint8_t *out, size_t outlen,
+ const ngtcp2_datagram *fr) {
+ uint64_t datalen = ngtcp2_vec_len(fr->data, fr->datacnt);
+ uint64_t len =
+ 1 +
+ (fr->type == NGTCP2_FRAME_DATAGRAM ? 0 : ngtcp2_put_uvarintlen(datalen)) +
+ datalen;
+ uint8_t *p;
+ size_t i;
+
+ assert(fr->type == NGTCP2_FRAME_DATAGRAM ||
+ fr->type == NGTCP2_FRAME_DATAGRAM_LEN);
+
+ if (outlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = out;
+
+ *p++ = fr->type;
+ if (fr->type == NGTCP2_FRAME_DATAGRAM_LEN) {
+ p = ngtcp2_put_uvarint(p, datalen);
+ }
+
+ for (i = 0; i < fr->datacnt; ++i) {
+ assert(fr->data[i].len);
+ assert(fr->data[i].base);
+ p = ngtcp2_cpymem(p, fr->data[i].base, fr->data[i].len);
+ }
+
+ assert((size_t)(p - out) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+ngtcp2_ssize ngtcp2_pkt_write_version_negotiation(
+ uint8_t *dest, size_t destlen, uint8_t unused_random, const uint8_t *dcid,
+ size_t dcidlen, const uint8_t *scid, size_t scidlen, const uint32_t *sv,
+ size_t nsv) {
+ size_t len = 1 + 4 + 1 + dcidlen + 1 + scidlen + nsv * 4;
+ uint8_t *p;
+ size_t i;
+
+ assert(dcidlen < 256);
+ assert(scidlen < 256);
+
+ if (destlen < len) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = dest;
+
+ *p++ = 0x80 | unused_random;
+ p = ngtcp2_put_uint32be(p, 0);
+ *p++ = (uint8_t)dcidlen;
+ if (dcidlen) {
+ p = ngtcp2_cpymem(p, dcid, dcidlen);
+ }
+ *p++ = (uint8_t)scidlen;
+ if (scidlen) {
+ p = ngtcp2_cpymem(p, scid, scidlen);
+ }
+
+ for (i = 0; i < nsv; ++i) {
+ p = ngtcp2_put_uint32be(p, sv[i]);
+ }
+
+ assert((size_t)(p - dest) == len);
+
+ return (ngtcp2_ssize)len;
+}
+
+size_t ngtcp2_pkt_decode_version_negotiation(uint32_t *dest,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ const uint8_t *end = payload + payloadlen;
+
+ assert((payloadlen % sizeof(uint32_t)) == 0);
+
+ for (; payload != end;) {
+ payload = ngtcp2_get_uint32(dest++, payload);
+ }
+
+ return payloadlen / sizeof(uint32_t);
+}
+
+int ngtcp2_pkt_decode_stateless_reset(ngtcp2_pkt_stateless_reset *sr,
+ const uint8_t *payload,
+ size_t payloadlen) {
+ const uint8_t *p = payload;
+
+ if (payloadlen <
+ NGTCP2_MIN_STATELESS_RESET_RANDLEN + NGTCP2_STATELESS_RESET_TOKENLEN) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ sr->rand = p;
+ sr->randlen = payloadlen - NGTCP2_STATELESS_RESET_TOKENLEN;
+ p += sr->randlen;
+ memcpy(sr->stateless_reset_token, p, NGTCP2_STATELESS_RESET_TOKENLEN);
+
+ return 0;
+}
+
+int ngtcp2_pkt_decode_retry(ngtcp2_pkt_retry *dest, const uint8_t *payload,
+ size_t payloadlen) {
+ size_t len = /* token */ 1 + NGTCP2_RETRY_TAGLEN;
+
+ if (payloadlen < len) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ dest->token.base = (uint8_t *)payload;
+ dest->token.len = (size_t)(payloadlen - NGTCP2_RETRY_TAGLEN);
+ ngtcp2_cpymem(dest->tag, payload + dest->token.len, NGTCP2_RETRY_TAGLEN);
+
+ return 0;
+}
+
+int64_t ngtcp2_pkt_adjust_pkt_num(int64_t max_pkt_num, int64_t pkt_num,
+ size_t n) {
+ int64_t expected = max_pkt_num + 1;
+ int64_t win = (int64_t)1 << n;
+ int64_t hwin = win / 2;
+ int64_t mask = win - 1;
+ int64_t cand = (expected & ~mask) | pkt_num;
+
+ if (cand <= expected - hwin) {
+ assert(cand <= (int64_t)NGTCP2_MAX_VARINT - win);
+ return cand + win;
+ }
+ if (cand > expected + hwin && cand >= win) {
+ return cand - win;
+ }
+ return cand;
+}
+
+int ngtcp2_pkt_validate_ack(ngtcp2_ack *fr) {
+ int64_t largest_ack = fr->largest_ack;
+ size_t i;
+
+ if (largest_ack < (int64_t)fr->first_ack_range) {
+ return NGTCP2_ERR_ACK_FRAME;
+ }
+
+ largest_ack -= (int64_t)fr->first_ack_range;
+
+ for (i = 0; i < fr->rangecnt; ++i) {
+ if (largest_ack < (int64_t)fr->ranges[i].gap + 2) {
+ return NGTCP2_ERR_ACK_FRAME;
+ }
+
+ largest_ack -= (int64_t)fr->ranges[i].gap + 2;
+
+ if (largest_ack < (int64_t)fr->ranges[i].len) {
+ return NGTCP2_ERR_ACK_FRAME;
+ }
+
+ largest_ack -= (int64_t)fr->ranges[i].len;
+ }
+
+ return 0;
+}
+
+ngtcp2_ssize
+ngtcp2_pkt_write_stateless_reset(uint8_t *dest, size_t destlen,
+ const uint8_t *stateless_reset_token,
+ const uint8_t *rand, size_t randlen) {
+ uint8_t *p;
+
+ if (destlen <
+ NGTCP2_MIN_STATELESS_RESET_RANDLEN + NGTCP2_STATELESS_RESET_TOKENLEN) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ if (randlen < NGTCP2_MIN_STATELESS_RESET_RANDLEN) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ p = dest;
+
+ randlen = ngtcp2_min(destlen - NGTCP2_STATELESS_RESET_TOKENLEN, randlen);
+
+ p = ngtcp2_cpymem(p, rand, randlen);
+ p = ngtcp2_cpymem(p, stateless_reset_token, NGTCP2_STATELESS_RESET_TOKENLEN);
+ *dest = (uint8_t)((*dest & 0x7fu) | 0x40u);
+
+ return p - dest;
+}
+
+ngtcp2_ssize ngtcp2_pkt_write_retry(
+ uint8_t *dest, size_t destlen, uint32_t version, const ngtcp2_cid *dcid,
+ const ngtcp2_cid *scid, const ngtcp2_cid *odcid, const uint8_t *token,
+ size_t tokenlen, ngtcp2_encrypt encrypt, const ngtcp2_crypto_aead *aead,
+ const ngtcp2_crypto_aead_ctx *aead_ctx) {
+ ngtcp2_pkt_hd hd;
+ uint8_t pseudo_retry[1500];
+ ngtcp2_ssize pseudo_retrylen;
+ uint8_t tag[NGTCP2_RETRY_TAGLEN];
+ int rv;
+ uint8_t *p;
+ size_t offset;
+ const uint8_t *nonce;
+ size_t noncelen;
+
+ assert(tokenlen > 0);
+ assert(!ngtcp2_cid_eq(scid, odcid));
+
+ /* Retry packet is sent at most once per one connection attempt. In
+ the first connection attempt, client has to send random DCID
+ which is at least NGTCP2_MIN_INITIAL_DCIDLEN bytes long. */
+ if (odcid->datalen < NGTCP2_MIN_INITIAL_DCIDLEN) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ ngtcp2_pkt_hd_init(&hd, NGTCP2_PKT_FLAG_LONG_FORM, NGTCP2_PKT_RETRY, dcid,
+ scid, /* pkt_num = */ 0, /* pkt_numlen = */ 1, version,
+ /* len = */ 0);
+
+ pseudo_retrylen =
+ ngtcp2_pkt_encode_pseudo_retry(pseudo_retry, sizeof(pseudo_retry), &hd,
+ /* unused = */ 0, odcid, token, tokenlen);
+ if (pseudo_retrylen < 0) {
+ return pseudo_retrylen;
+ }
+
+ switch (version) {
+ case NGTCP2_PROTO_VER_V1:
+ nonce = (const uint8_t *)NGTCP2_RETRY_NONCE_V1;
+ noncelen = sizeof(NGTCP2_RETRY_NONCE_V1) - 1;
+ break;
+ case NGTCP2_PROTO_VER_V2_DRAFT:
+ nonce = (const uint8_t *)NGTCP2_RETRY_NONCE_V2_DRAFT;
+ noncelen = sizeof(NGTCP2_RETRY_NONCE_V2_DRAFT) - 1;
+ break;
+ default:
+ nonce = (const uint8_t *)NGTCP2_RETRY_NONCE_DRAFT;
+ noncelen = sizeof(NGTCP2_RETRY_NONCE_DRAFT) - 1;
+ }
+
+ /* OpenSSL does not like NULL plaintext. */
+ rv = encrypt(tag, aead, aead_ctx, (const uint8_t *)"", 0, nonce, noncelen,
+ pseudo_retry, (size_t)pseudo_retrylen);
+ if (rv != 0) {
+ return rv;
+ }
+
+ offset = 1 + odcid->datalen;
+ if (destlen < (size_t)pseudo_retrylen + sizeof(tag) - offset) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ p = ngtcp2_cpymem(dest, pseudo_retry + offset,
+ (size_t)pseudo_retrylen - offset);
+ p = ngtcp2_cpymem(p, tag, sizeof(tag));
+
+ return p - dest;
+}
+
+ngtcp2_ssize ngtcp2_pkt_encode_pseudo_retry(
+ uint8_t *dest, size_t destlen, const ngtcp2_pkt_hd *hd, uint8_t unused,
+ const ngtcp2_cid *odcid, const uint8_t *token, size_t tokenlen) {
+ uint8_t *p = dest;
+ ngtcp2_ssize nwrite;
+
+ if (destlen < 1 + odcid->datalen) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ *p++ = (uint8_t)odcid->datalen;
+ p = ngtcp2_cpymem(p, odcid->data, odcid->datalen);
+ destlen -= (size_t)(p - dest);
+
+ nwrite = ngtcp2_pkt_encode_hd_long(p, destlen, hd);
+ if (nwrite < 0) {
+ return nwrite;
+ }
+
+ if (destlen < (size_t)nwrite + tokenlen) {
+ return NGTCP2_ERR_NOBUF;
+ }
+
+ *p &= 0xf0;
+ *p |= unused;
+
+ p += nwrite;
+
+ p = ngtcp2_cpymem(p, token, tokenlen);
+
+ return p - dest;
+}
+
+int ngtcp2_pkt_verify_retry_tag(uint32_t version, const ngtcp2_pkt_retry *retry,
+ const uint8_t *pkt, size_t pktlen,
+ ngtcp2_encrypt encrypt,
+ const ngtcp2_crypto_aead *aead,
+ const ngtcp2_crypto_aead_ctx *aead_ctx) {
+ uint8_t pseudo_retry[1500];
+ size_t pseudo_retrylen;
+ uint8_t *p = pseudo_retry;
+ int rv;
+ uint8_t tag[NGTCP2_RETRY_TAGLEN];
+ const uint8_t *nonce;
+ size_t noncelen;
+
+ assert(pktlen >= sizeof(retry->tag));
+
+ if (sizeof(pseudo_retry) <
+ 1 + retry->odcid.datalen + pktlen - sizeof(retry->tag)) {
+ return NGTCP2_ERR_PROTO;
+ }
+
+ *p++ = (uint8_t)retry->odcid.datalen;
+ p = ngtcp2_cpymem(p, retry->odcid.data, retry->odcid.datalen);
+ p = ngtcp2_cpymem(p, pkt, pktlen - sizeof(retry->tag));
+
+ pseudo_retrylen = (size_t)(p - pseudo_retry);
+
+ switch (version) {
+ case NGTCP2_PROTO_VER_V1:
+ nonce = (const uint8_t *)NGTCP2_RETRY_NONCE_V1;
+ noncelen = sizeof(NGTCP2_RETRY_NONCE_V1) - 1;
+ break;
+ case NGTCP2_PROTO_VER_V2_DRAFT:
+ nonce = (const uint8_t *)NGTCP2_RETRY_NONCE_V2_DRAFT;
+ noncelen = sizeof(NGTCP2_RETRY_NONCE_V2_DRAFT) - 1;
+ break;
+ default:
+ nonce = (const uint8_t *)NGTCP2_RETRY_NONCE_DRAFT;
+ noncelen = sizeof(NGTCP2_RETRY_NONCE_DRAFT) - 1;
+ }
+
+ /* OpenSSL does not like NULL plaintext. */
+ rv = encrypt(tag, aead, aead_ctx, (const uint8_t *)"", 0, nonce, noncelen,
+ pseudo_retry, pseudo_retrylen);
+ if (rv != 0) {
+ return rv;
+ }
+
+ if (0 != memcmp(retry->tag, tag, sizeof(retry->tag))) {
+ return NGTCP2_ERR_PROTO;
+ }
+
+ return 0;
+}
+
+size_t ngtcp2_pkt_stream_max_datalen(int64_t stream_id, uint64_t offset,
+ uint64_t len, size_t left) {
+ size_t n = 1 /* type */ + ngtcp2_put_uvarintlen((uint64_t)stream_id) +
+ (offset ? ngtcp2_put_uvarintlen(offset) : 0);
+
+ if (left <= n) {
+ return (size_t)-1;
+ }
+
+ left -= n;
+
+ if (left > 8 + 1073741823 && len > 1073741823) {
+#if SIZE_MAX > UINT32_MAX
+ len = ngtcp2_min(len, 4611686018427387903lu);
+#endif /* SIZE_MAX > UINT32_MAX */
+ return (size_t)ngtcp2_min(len, (uint64_t)(left - 8));
+ }
+
+ if (left > 4 + 16383 && len > 16383) {
+ len = ngtcp2_min(len, 1073741823);
+ return (size_t)ngtcp2_min(len, (uint64_t)(left - 4));
+ }
+
+ if (left > 2 + 63 && len > 63) {
+ len = ngtcp2_min(len, 16383);
+ return (size_t)ngtcp2_min(len, (uint64_t)(left - 2));
+ }
+
+ len = ngtcp2_min(len, 63);
+ return (size_t)ngtcp2_min(len, (uint64_t)(left - 1));
+}
+
+size_t ngtcp2_pkt_crypto_max_datalen(uint64_t offset, size_t len, size_t left) {
+ size_t n = 1 /* type */ + ngtcp2_put_uvarintlen(offset);
+
+ /* CRYPTO frame must contain nonzero length data. Return -1 if
+ there is no space to write crypto data. */
+ if (left <= n + 1) {
+ return (size_t)-1;
+ }
+
+ left -= n;
+
+ if (left > 8 + 1073741823 && len > 1073741823) {
+#if SIZE_MAX > UINT32_MAX
+ len = ngtcp2_min(len, 4611686018427387903lu);
+#endif /* SIZE_MAX > UINT32_MAX */
+ return ngtcp2_min(len, left - 8);
+ }
+
+ if (left > 4 + 16383 && len > 16383) {
+ len = ngtcp2_min(len, 1073741823);
+ return ngtcp2_min(len, left - 4);
+ }
+
+ if (left > 2 + 63 && len > 63) {
+ len = ngtcp2_min(len, 16383);
+ return ngtcp2_min(len, left - 2);
+ }
+
+ len = ngtcp2_min(len, 63);
+ return ngtcp2_min(len, left - 1);
+}
+
+size_t ngtcp2_pkt_datagram_framelen(size_t len) {
+ return 1 /* type */ + ngtcp2_put_uvarintlen(len) + len;
+}
+
+int ngtcp2_is_supported_version(uint32_t version) {
+ switch (version) {
+ case NGTCP2_PROTO_VER_V1:
+ case NGTCP2_PROTO_VER_V2_DRAFT:
+ return 1;
+ default:
+ return NGTCP2_PROTO_VER_DRAFT_MIN <= version &&
+ version <= NGTCP2_PROTO_VER_DRAFT_MAX;
+ }
+}
+
+int ngtcp2_is_reserved_version(uint32_t version) {
+ return (version & NGTCP2_RESERVED_VERSION_MASK) ==
+ NGTCP2_RESERVED_VERSION_MASK;
+}
+
+uint8_t ngtcp2_pkt_get_type_long(uint32_t version, uint8_t c) {
+ uint8_t pkt_type = (uint8_t)((c & NGTCP2_LONG_TYPE_MASK) >> 4);
+
+ switch (version) {
+ case NGTCP2_PROTO_VER_V2_DRAFT:
+ switch (pkt_type) {
+ case NGTCP2_PKT_TYPE_INITIAL_V2_DRAFT:
+ return NGTCP2_PKT_INITIAL;
+ case NGTCP2_PKT_TYPE_0RTT_V2_DRAFT:
+ return NGTCP2_PKT_0RTT;
+ case NGTCP2_PKT_TYPE_HANDSHAKE_V2_DRAFT:
+ return NGTCP2_PKT_HANDSHAKE;
+ case NGTCP2_PKT_TYPE_RETRY_V2_DRAFT:
+ return NGTCP2_PKT_RETRY;
+ default:
+ return 0;
+ }
+ default:
+ if (!ngtcp2_is_supported_version(version)) {
+ return 0;
+ }
+
+ /* QUIC v1 and draft versions share the same numeric packet
+ types. */
+ switch (pkt_type) {
+ case NGTCP2_PKT_TYPE_INITIAL_V1:
+ return NGTCP2_PKT_INITIAL;
+ case NGTCP2_PKT_TYPE_0RTT_V1:
+ return NGTCP2_PKT_0RTT;
+ case NGTCP2_PKT_TYPE_HANDSHAKE_V1:
+ return NGTCP2_PKT_HANDSHAKE;
+ case NGTCP2_PKT_TYPE_RETRY_V1:
+ return NGTCP2_PKT_RETRY;
+ default:
+ return 0;
+ }
+ }
+}
+
+uint8_t ngtcp2_pkt_versioned_type(uint32_t version, uint32_t pkt_type) {
+ switch (version) {
+ case NGTCP2_PROTO_VER_V2_DRAFT:
+ switch (pkt_type) {
+ case NGTCP2_PKT_INITIAL:
+ return NGTCP2_PKT_TYPE_INITIAL_V2_DRAFT;
+ case NGTCP2_PKT_0RTT:
+ return NGTCP2_PKT_TYPE_0RTT_V2_DRAFT;
+ case NGTCP2_PKT_HANDSHAKE:
+ return NGTCP2_PKT_TYPE_HANDSHAKE_V2_DRAFT;
+ case NGTCP2_PKT_RETRY:
+ return NGTCP2_PKT_TYPE_RETRY_V2_DRAFT;
+ default:
+ ngtcp2_unreachable();
+ }
+ default:
+ /* Assume that unsupported versions share the numeric long packet
+ types with QUIC v1 in order to send a packet to elicit Version
+ Negotiation packet. */
+
+ /* QUIC v1 and draft versions share the same numeric packet
+ types. */
+ switch (pkt_type) {
+ case NGTCP2_PKT_INITIAL:
+ return NGTCP2_PKT_TYPE_INITIAL_V1;
+ case NGTCP2_PKT_0RTT:
+ return NGTCP2_PKT_TYPE_0RTT_V1;
+ case NGTCP2_PKT_HANDSHAKE:
+ return NGTCP2_PKT_TYPE_HANDSHAKE_V1;
+ case NGTCP2_PKT_RETRY:
+ return NGTCP2_PKT_TYPE_RETRY_V1;
+ default:
+ ngtcp2_unreachable();
+ }
+ }
+}
+
+int ngtcp2_pkt_verify_reserved_bits(uint8_t c) {
+ if (c & NGTCP2_HEADER_FORM_BIT) {
+ return (c & NGTCP2_LONG_RESERVED_BIT_MASK) == 0 ? 0 : NGTCP2_ERR_PROTO;
+ }
+ return (c & NGTCP2_SHORT_RESERVED_BIT_MASK) == 0 ? 0 : NGTCP2_ERR_PROTO;
+}