Generic payload handler for quic packets.

- added basic parsing of ACK, PING and PADDING frames on input
 - added preliminary parsing of SHORT headers

The ngx_quic_output() is now called after processing of each input packet.
Frames are added into output queue according to their level: inital packets
go ahead of handshake and application data, so they can be merged properly.

The payload handler is called from both new, handshake and applicataion data
handlers (latter is a stub).
This commit is contained in:
Vladimir Homutov 2020-03-10 18:24:39 +03:00
parent f1d376e384
commit 9bb1eba59e

View file

@ -134,12 +134,23 @@ typedef enum ssl_encryption_level_t ngx_quic_level_t;
typedef struct ngx_quic_frame_s ngx_quic_frame_t;
typedef struct {
ngx_uint_t pn;
// ngx_uint_t nranges;
// ...
ngx_uint_t pn;
// input
uint64_t largest;
uint64_t delay;
uint64_t range_count;
uint64_t first_range;
uint64_t ranges[20];
/* ecn counts */
} ngx_quic_ack_frame_t;
typedef ngx_str_t ngx_quic_crypto_frame_t;
typedef struct {
size_t offset;
size_t len;
u_char *data;
} ngx_quic_crypto_frame_t;
struct ngx_quic_frame_s {
ngx_uint_t type;
@ -207,6 +218,7 @@ typedef struct {
static ngx_int_t ngx_quic_new_connection(ngx_connection_t *c, ngx_ssl_t *ssl,
ngx_buf_t *b);
static ngx_int_t ngx_quic_handshake_input(ngx_connection_t *c, ngx_buf_t *b);
static ngx_int_t ngx_quic_app_input(ngx_connection_t *c, ngx_buf_t *b);
static int ngx_quic_set_encryption_secrets(ngx_ssl_conn_t *ssl_conn,
enum ssl_encryption_level_t level, const uint8_t *read_secret,
@ -225,6 +237,8 @@ static int ngx_quic_send_alert(ngx_ssl_conn_t *ssl_conn,
static ngx_int_t ngx_quic_process_long_header(ngx_connection_t *c,
ngx_quic_header_t *pkt);
static ngx_int_t ngx_quic_process_short_header(ngx_connection_t *c,
ngx_quic_header_t *pkt);
static ngx_int_t ngx_quic_process_initial_header(ngx_connection_t *c,
ngx_quic_header_t *pkt);
static ngx_int_t ngx_quic_process_handshake_header(ngx_connection_t *c,
@ -276,19 +290,15 @@ ngx_int_t
ngx_quic_input(ngx_connection_t *c, ngx_ssl_t *ssl, ngx_buf_t *b)
{
if (c->quic == NULL) {
return ngx_quic_new_connection(c, ssl, b); //TODO: change state by results
return ngx_quic_new_connection(c, ssl, b);
}
switch (c->quic->state) {
case NGX_QUIC_ST_INITIAL:
case NGX_QUIC_ST_HANDSHAKE:
if (b->start[0] & NGX_QUIC_PKT_LONG) {
// TODO: check current state
return ngx_quic_handshake_input(c, b);
default:
/* application data */
break;
}
return NGX_OK;
return ngx_quic_app_input(c, b);
}
static ngx_int_t
@ -379,7 +389,7 @@ ngx_quic_create_crypto(u_char *p, ngx_quic_crypto_frame_t *crypto)
start = p;
ngx_quic_build_int(&p, NGX_QUIC_FT_CRYPTO);
ngx_quic_build_int(&p, 0);
ngx_quic_build_int(&p, crypto->offset);
ngx_quic_build_int(&p, crypto->len);
p = ngx_cpymem(p, crypto->data, crypto->len);
@ -453,6 +463,7 @@ ngx_quic_frames_send(ngx_connection_t *c, ngx_quic_frame_t *start,
return NGX_OK;
}
ngx_int_t
ngx_quic_output(ngx_connection_t *c)
{
@ -802,8 +813,13 @@ ngx_quic_queue_frame(ngx_quic_connection_t *qc, ngx_quic_frame_t *frame)
return;
}
for (f = qc->frames; f->next; f = f->next) { /* void */ }
for (f = qc->frames; f->next; f = f->next) {
if (f->next->level > frame->level) {
break;
}
}
frame->next = f->next;
f->next = frame;
}
@ -844,19 +860,6 @@ ngx_quic_add_handshake_data(ngx_ssl_conn_t *ssl_conn,
ngx_quic_queue_frame(qc, frame);
if (level == ssl_encryption_initial) {
frame = ngx_pcalloc(c->pool, sizeof(ngx_quic_frame_t));
if (frame == NULL) {
return 0;
}
frame->level = level;
frame->type = NGX_QUIC_FT_ACK;
frame->u.ack.pn = 0;
ngx_sprintf(frame->info, "ACK for PN=0 at initial, added manually from add_handshake_data");
ngx_quic_queue_frame(qc, frame);
}
return 1;
}
@ -870,10 +873,6 @@ ngx_quic_flush_flight(ngx_ssl_conn_t *ssl_conn)
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0, "ngx_quic_flush_flight()");
if (ngx_quic_output(c) != NGX_OK) {
return 0;
}
return 1;
}
@ -894,6 +893,40 @@ ngx_quic_send_alert(ngx_ssl_conn_t *ssl_conn, enum ssl_encryption_level_t level,
}
/* TODO: stub for short packet header processing */
static ngx_int_t
ngx_quic_process_short_header(ngx_connection_t *c, ngx_quic_header_t *pkt)
{
u_char *p;
p = pkt->buf.data;
ngx_quic_hexdump0(c->log, "input", pkt->buf.data, pkt->buf.len);
if ((p[0] & NGX_QUIC_PKT_LONG)) {
ngx_log_error(NGX_LOG_INFO, c->log, 0, "not a short packet");
return NGX_ERROR;
}
pkt->flags = *p++;
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
"quic flags:%xi", pkt->flags);
if (ngx_memcmp(p, c->quic->dcid.data, c->quic->dcid.len) != 0) {
ngx_log_error(NGX_LOG_INFO, c->log, 0, "unexpected quic dcid");
return NGX_ERROR;
}
pkt->dcid.data = p;
p += c->quic->dcid.len;
pkt->pos = p;
return NGX_OK;
}
static ngx_int_t
ngx_quic_process_long_header(ngx_connection_t *c, ngx_quic_header_t *pkt)
{
@ -1160,7 +1193,13 @@ ngx_quic_decrypt(ngx_connection_t *c, ngx_quic_header_t *pkt)
return NGX_ERROR;
}
clearflags = pkt->flags ^ (mask[0] & 0x0f);
if (pkt->flags & NGX_QUIC_PKT_LONG) {
clearflags = pkt->flags ^ (mask[0] & 0x0f);
} else {
clearflags = pkt->flags ^ (mask[0] & 0x1f);
}
pnl = (clearflags & 0x03) + 1;
pn = ngx_quic_parse_pn(&p, pnl, &mask[1]);
@ -1175,9 +1214,15 @@ ngx_quic_decrypt(ngx_connection_t *c, ngx_quic_header_t *pkt)
/* packet protection */
in.data = p;
in.len = pkt->buf.len - pnl;
ad.len = p - pkt->buf.data;;
if (pkt->flags & NGX_QUIC_PKT_LONG) {
in.len = pkt->buf.len - pnl;
} else {
in.len = pkt->buf.data + pkt->buf.len - p;
}
ad.len = p - pkt->buf.data;
ad.data = ngx_pnalloc(c->pool, ad.len);
if (ad.data == NULL) {
return NGX_ERROR;
@ -1199,15 +1244,278 @@ ngx_quic_decrypt(ngx_connection_t *c, ngx_quic_header_t *pkt)
ngx_quic_hexdump0(c->log, "packet payload",
pkt->payload.data, pkt->payload.len);
pkt->pos = pkt->payload.data;
return rc;
}
ngx_int_t
ngx_quic_read_frame(ngx_connection_t *c, ngx_quic_header_t *pkt,
ngx_quic_frame_t *frame)
{
u_char *p, *end;
size_t npad;
p = pkt->pos;
end = pkt->payload.data + pkt->payload.len;
frame->type = *p++;
switch (frame->type) {
case NGX_QUIC_FT_CRYPTO:
frame->u.crypto.offset = *p++;
frame->u.crypto.len = ngx_quic_parse_int(&p);
frame->u.crypto.data = p;
p += frame->u.crypto.len;
ngx_quic_hexdump0(c->log, "CRYPTO frame",
frame->u.crypto.data, frame->u.crypto.len);
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
"quic CRYPTO frame length: %uL off:%uL pp:%p",
frame->u.crypto.len, frame->u.crypto.offset,
frame->u.crypto.data);
break;
case NGX_QUIC_FT_PADDING:
npad = 0;
while (p < end && *p == NGX_QUIC_FT_PADDING) { // XXX
p++; npad++;
}
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
"PADDING frame length %uL", npad);
break;
case NGX_QUIC_FT_ACK:
case NGX_QUIC_FT_ACK_ECN:
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0, "ACK frame");
frame->u.ack.largest = ngx_quic_parse_int(&p);
frame->u.ack.delay = ngx_quic_parse_int(&p);
frame->u.ack.range_count =ngx_quic_parse_int(&p);
frame->u.ack.first_range =ngx_quic_parse_int(&p);
if (frame->u.ack.range_count) {
frame->u.ack.ranges[0] = ngx_quic_parse_int(&p);
}
if (frame->type ==NGX_QUIC_FT_ACK_ECN) {
return NGX_ERROR;
}
break;
case NGX_QUIC_FT_PING:
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0, "PING frame");
p++;
break;
default:
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
"unknown frame type %xi", frame->type);
return NGX_ERROR;
}
pkt->pos = p;
return NGX_OK;
}
static ngx_int_t
ngx_quic_handle_crypto_frame(ngx_connection_t *c, ngx_quic_header_t *pkt,
ngx_quic_frame_t *frame)
{
int sslerr;
ssize_t n;
ngx_ssl_conn_t *ssl_conn;
ssl_conn = c->ssl->connection;
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(ssl_conn),
(int) SSL_quic_write_level(ssl_conn));
if (!SSL_provide_quic_data(ssl_conn, SSL_quic_read_level(ssl_conn),
frame->u.crypto.data, frame->u.crypto.len))
{
ngx_ssl_error(NGX_LOG_INFO, c->log, 0,
"SSL_provide_quic_data() failed");
return NGX_ERROR;
}
n = SSL_do_handshake(ssl_conn);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_do_handshake: %d", n);
if (n == -1) {
sslerr = SSL_get_error(ssl_conn, n);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_get_error: %d",
sslerr);
if (sslerr == SSL_ERROR_SSL) {
ngx_ssl_error(NGX_LOG_ERR, c->log, 0, "SSL_do_handshake() failed");
}
}
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
"quic ssl cipher: %s", SSL_get_cipher(ssl_conn));
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(ssl_conn),
(int) SSL_quic_write_level(ssl_conn));
return NGX_OK;
}
static ngx_int_t
ngx_quic_init_connection(ngx_connection_t *c, ngx_quic_header_t *pkt)
{
int n, sslerr;
ngx_ssl_conn_t *ssl_conn;
ngx_quic_connection_t *qc;
/* STUB: initial_max_streams_uni=3, active_connection_id_limit=5 */
static const uint8_t params[12] = "\x00\x0a\x00\x0e\x00\x01\x05\x00\x09\x00\x01\x03";
qc = c->quic;
if (ngx_ssl_create_connection(qc->ssl, c, NGX_SSL_BUFFER) != NGX_OK) {
return NGX_ERROR;
}
ssl_conn = c->ssl->connection;
if (SSL_set_quic_transport_params(ssl_conn, params, sizeof(params)) == 0) {
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"SSL_set_quic_transport_params() failed");
return NGX_ERROR;
}
n = SSL_do_handshake(ssl_conn);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_do_handshake: %d", n);
if (n == -1) {
sslerr = SSL_get_error(ssl_conn, n);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_get_error: %d",
sslerr);
}
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(ssl_conn),
(int) SSL_quic_write_level(ssl_conn));
return NGX_OK;
}
/* process all payload from the current packet and generate ack if required */
static ngx_int_t
ngx_quic_payload_handler(ngx_connection_t *c, ngx_quic_header_t *pkt)
{
u_char *end;
ngx_uint_t ack_this;
ngx_quic_frame_t frame, *ack_frame;
ngx_quic_connection_t *qc;
qc = c->quic;
end = pkt->payload.data + pkt->payload.len;
ack_this = 0;
while (pkt->pos < end) {
if (ngx_quic_read_frame(c, pkt, &frame) != NGX_OK) {
return NGX_ERROR;
}
switch (frame.type) {
case NGX_QUIC_FT_ACK:
// TODO: handle ack
ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0,
"ACK: { largest=%ui delay=%ui first=%ui count=%ui}",
frame.u.ack.largest,
frame.u.ack.delay,
frame.u.ack.first_range,
frame.u.ack.range_count);
break;
case NGX_QUIC_FT_CRYPTO:
if (frame.u.crypto.offset != 0x0) {
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"crypto frame with non-zero offset");
// TODO: support packet spanning with offsets
return NGX_ERROR;
}
if (ngx_quic_handle_crypto_frame(c, pkt, &frame) != NGX_OK) {
return NGX_ERROR;
}
ack_this = 1;
continue;
case NGX_QUIC_FT_PADDING:
continue;
case NGX_QUIC_FT_PING:
ack_this = 1;
continue;
default:
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"unexpected frame type 0x%xd in packet", frame.type);
return NGX_ERROR;
}
}
if (ack_this == 0) {
/* do not ack packets with ACKs and PADDING */
return NGX_OK;
}
// packet processed, ACK it now if required
// TODO: if (ack_required) ... - currently just ack each packet
ack_frame = ngx_pcalloc(c->pool, sizeof(ngx_quic_frame_t));
if (ack_frame == NULL) {
return NGX_ERROR;
}
ack_frame->level = pkt->level;
ack_frame->type = NGX_QUIC_FT_ACK;
ack_frame->u.ack.pn = pkt->pn;
ngx_sprintf(ack_frame->info, "ACK for PN=%d from frame handler", pkt->pn);
ngx_quic_queue_frame(qc, ack_frame);
return ngx_quic_output(c);
}
static ngx_int_t
ngx_quic_new_connection(ngx_connection_t *c, ngx_ssl_t *ssl, ngx_buf_t *b)
{
int n, sslerr;
ngx_str_t out;
ngx_quic_connection_t *qc;
ngx_quic_header_t pkt = { 0 };
@ -1240,6 +1548,7 @@ ngx_quic_new_connection(ngx_connection_t *c, ngx_ssl_t *ssl, ngx_buf_t *b)
}
c->quic = qc;
qc->ssl = ssl;
qc->dcid.len = pkt.dcid.len;
qc->dcid.data = ngx_pnalloc(c->pool, pkt.dcid.len);
@ -1268,102 +1577,23 @@ ngx_quic_new_connection(ngx_connection_t *c, ngx_ssl_t *ssl, ngx_buf_t *b)
}
pkt.secret = &qc->client_in;
pkt.level = ssl_encryption_initial;
if (ngx_quic_decrypt(c, &pkt) != NGX_OK) {
return NGX_ERROR;
}
out = pkt.payload;
if (out.data[0] != NGX_QUIC_FT_CRYPTO) {
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"unexpected frame in initial packet");
if (ngx_quic_init_connection(c, &pkt) != NGX_OK) {
return NGX_ERROR;
}
if (out.data[1] != 0x00) {
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"unexpected CRYPTO offset in initial packet");
return NGX_ERROR;
}
uint8_t *crypto = &out.data[2];
uint64_t crypto_len = ngx_quic_parse_int(&crypto);
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
"quic initial packet CRYPTO length: %uL pp:%p:%p",
crypto_len, out.data, crypto);
if (ngx_ssl_create_connection(ssl, c, NGX_SSL_BUFFER) != NGX_OK) {
return NGX_ERROR;
}
/* STUB: initial_max_streams_uni=3, active_connection_id_limit=5 */
static const uint8_t params[12] = "\x00\x0a\x00\x0e\x00\x01\x05\x00\x09\x00\x01\x03";
if (SSL_set_quic_transport_params(c->ssl->connection, params,
sizeof(params)) == 0)
{
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"SSL_set_quic_transport_params() failed");
return NGX_ERROR;
}
n = SSL_do_handshake(c->ssl->connection);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_do_handshake: %d", n);
if (n == -1) {
sslerr = SSL_get_error(c->ssl->connection, n);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_get_error: %d",
sslerr);
}
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(c->ssl->connection),
(int) SSL_quic_write_level(c->ssl->connection));
if (!SSL_provide_quic_data(c->ssl->connection,
SSL_quic_read_level(c->ssl->connection),
crypto, crypto_len))
{
ngx_ssl_error(NGX_LOG_INFO, c->log, 0,
"SSL_provide_quic_data() failed");
return NGX_ERROR;
}
n = SSL_do_handshake(c->ssl->connection);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_do_handshake: %d", n);
if (n == -1) {
sslerr = SSL_get_error(c->ssl->connection, n);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_get_error: %d",
sslerr);
if (sslerr == SSL_ERROR_SSL) {
ngx_ssl_error(NGX_LOG_ERR, c->log, 0, "SSL_do_handshake() failed");
}
}
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(c->ssl->connection),
(int) SSL_quic_write_level(c->ssl->connection));
return NGX_OK;
return ngx_quic_payload_handler(c, &pkt);
}
static ngx_int_t
ngx_quic_handshake_input(ngx_connection_t *c, ngx_buf_t *b)
{
int sslerr;
ssize_t n;
ngx_str_t out;
ngx_ssl_conn_t *ssl_conn;
ngx_quic_connection_t *qc;
@ -1411,89 +1641,42 @@ ngx_quic_handshake_input(ngx_connection_t *c, ngx_buf_t *b)
}
pkt.secret = &qc->client_hs;
pkt.level = ssl_encryption_handshake;
if (ngx_quic_decrypt(c, &pkt) != NGX_OK) {
return NGX_ERROR;
}
out = pkt.payload;
return ngx_quic_payload_handler(c, &pkt);
}
if (out.data[0] != NGX_QUIC_FT_CRYPTO) {
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"non-CRYPTO frame in HS packet, skipping");
return NGX_OK;
}
if (out.data[1] != 0x00) {
ngx_log_error(NGX_LOG_INFO, c->log, 0,
"not yet supported CRYPTO offset in initial packet");
static ngx_int_t
ngx_quic_app_input(ngx_connection_t *c, ngx_buf_t *b)
{
ngx_quic_connection_t *qc;
qc = c->quic;
/* TODO: this is a stub, untested */
ngx_quic_header_t pkt = { 0 };
pkt.buf.data = b->start;
pkt.buf.len = b->last - b->pos;
if (ngx_quic_process_short_header(c, &pkt) != NGX_OK) {
return NGX_ERROR;
}
uint8_t *crypto = &out.data[2];
uint64_t crypto_len = ngx_quic_parse_int(&crypto);
pkt.secret = &qc->client_ad;
pkt.level = ssl_encryption_application;
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
"quic Handshake packet CRYPTO length: %uL pp:%p:%p",
crypto_len, out.data, crypto);
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(ssl_conn),
(int) SSL_quic_write_level(ssl_conn));
if (!SSL_provide_quic_data(ssl_conn, SSL_quic_read_level(ssl_conn),
crypto, crypto_len))
{
ngx_ssl_error(NGX_LOG_INFO, c->log, 0,
"SSL_provide_quic_data() failed");
if (ngx_quic_decrypt(c, &pkt) != NGX_OK) {
return NGX_ERROR;
}
n = SSL_do_handshake(ssl_conn);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_do_handshake: %d", n);
if (n == -1) {
sslerr = SSL_get_error(ssl_conn, n);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_get_error: %d",
sslerr);
if (sslerr == SSL_ERROR_SSL) {
ngx_ssl_error(NGX_LOG_ERR, c->log, 0, "SSL_do_handshake() failed");
}
}
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"SSL_quic_read_level: %d, SSL_quic_write_level: %d",
(int) SSL_quic_read_level(ssl_conn),
(int) SSL_quic_write_level(ssl_conn));
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
"quic ssl cipher: %s", SSL_get_cipher(ssl_conn));
// ACK Client Finished
ngx_quic_frame_t *frame;
frame = ngx_pcalloc(c->pool, sizeof(ngx_quic_frame_t));
if (frame == NULL) {
return 0;
}
frame->level = ssl_encryption_handshake;
frame->type = NGX_QUIC_FT_ACK;
frame->u.ack.pn = pkt.pn;
ngx_sprintf(frame->info, "ACK for PN=%d at handshake level, in respond to client finished", pkt.pn);
ngx_quic_queue_frame(qc, frame);
if (ngx_quic_output(c) != NGX_OK) {
return 0;
}
return NGX_OK;
return ngx_quic_payload_handler(c, &pkt);
}