http2 hpack basic decode ok including huff
Signed-off-by: Andy Green <andy.green@linaro.org>
diff --git a/lib/hpack.c b/lib/hpack.c
index 0d19815..1bda810 100644
--- a/lib/hpack.c
+++ b/lib/hpack.c
@@ -1,4 +1,27 @@
/*
+ * lib/hpack.c
+ *
+ * Copyright (C) 2014 Andy Green <andy@warmcat.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation:
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include "private-libwebsockets.h"
+
+/*
* Official static header table for HPACK
* +-------+-----------------------------+---------------+
| 1 | :authority | |
@@ -104,7 +127,7 @@
WSI_TOKEN_HTTP_EXPECT,
WSI_TOKEN_HTTP_EXPIRES,
WSI_TOKEN_HTTP_FROM,
- WSI_TOKEN_HTTP_HOST,
+ WSI_TOKEN_HOST,
WSI_TOKEN_HTTP_IF_MATCH,
WSI_TOKEN_HTTP_IF_MODIFIED_SINCE,
WSI_TOKEN_HTTP_IF_NONE_MATCH,
@@ -130,6 +153,8 @@
WSI_TOKEN_HTTP_WWW_AUTHENTICATE,
};
+/* some of the entries imply values as well as header names */
+
static const char * const http2_canned[] = {
"",
"",
@@ -142,7 +167,6 @@
"200",
"204",
"206",
- "300",
"304",
"400",
"404",
@@ -151,9 +175,11 @@
"gzip, deflate"
};
+/* see minihuf.c */
+
#include "huftable.h"
-int lextable_decode(int pos, char c)
+static int huftable_decode(int pos, char c)
{
int q = pos + !!c;
@@ -163,77 +189,282 @@
return pos + (lextable[q] << 1);
}
-static int lws_add_header(int header, const char *payload, int len)
+static int lws_hpack_update_table_size(struct libwebsocket *wsi, int idx)
{
- wsi->u.ah.frag_index[header]
+ lwsl_info("hpack set table size %d\n", idx);
+ return 0;
}
-int lws_hpack_interpret(struct libwebsocket *wsi, unsigned char c)
+static int lws_frag_start(struct libwebsocket *wsi, int hdr_token_idx)
{
+ struct allocated_headers * ah = wsi->u.http2.http.ah;
+
+ if (!hdr_token_idx)
+ return 1;
+
+ if (ah->next_frag_index >= ARRAY_SIZE(ah->frag_index))
+ return 1;
+
+ ah->frags[ah->next_frag_index].offset = ah->pos;
+ ah->frags[ah->next_frag_index].len = 0;
+ ah->frags[ah->next_frag_index].next_frag_index = 0;
+
+ ah->frag_index[hdr_token_idx] = ah->next_frag_index;
+
+ return 0;
+}
+
+static int lws_frag_append(struct libwebsocket *wsi, unsigned char c)
+{
+ struct allocated_headers * ah = wsi->u.http2.http.ah;
+
+ ah->data[ah->pos++] = c;
+ ah->frags[ah->next_frag_index].len++;
+
+ return ah->pos >= sizeof(ah->data);
+}
+
+static int lws_frag_end(struct libwebsocket *wsi)
+{
+ if (lws_frag_append(wsi, 0))
+ return 1;
+
+ wsi->u.http2.http.ah->next_frag_index++;
+ return 0;
+}
+
+static void lws_dump_header(struct libwebsocket *wsi, int hdr)
+{
+ char s[200];
+ int len = lws_hdr_copy(wsi, s, sizeof(s) - 1, hdr);
+ s[len] = '\0';
+ lwsl_info(" hdr tok %d '%s'\n", hdr, s);
+}
+
+static int lws_token_from_index(struct libwebsocket *wsi, int index)
+{
+ if (index < ARRAY_SIZE(static_token))
+ return static_token[index];
+
+ // dynamic indexes
+
+ return 0;
+}
+
+static int lws_add_indexed_hdr(struct libwebsocket *wsi, int idx)
+{
+ const char *p;
+ int tok = lws_token_from_index(wsi, idx);
+
+ lwsl_info("adding indexed hdr %d (tok %d)\n", idx, tok);
+
+ if (lws_frag_start(wsi, tok))
+ return 1;
+
+ if (idx < ARRAY_SIZE(http2_canned)) {
+ p = http2_canned[idx];
+ while (*p)
+ if (lws_frag_append(wsi, *p++))
+ return 1;
+ }
+ if (lws_frag_end(wsi))
+ return 1;
+
+ lws_dump_header(wsi, tok);
+
+ return 0;
+}
+
+int lws_hpack_interpret(struct libwebsocket_context *context,
+ struct libwebsocket *wsi, unsigned char c)
+{
+ unsigned int prev;
+ unsigned char c1;
+ int n;
+
switch (wsi->u.http2.hpack) {
case HPKS_TYPE:
if (c & 0x80) { /* indexed header field only */
+ /* just a possibly-extended integer */
+ wsi->u.http2.hpack_type = HPKT_INDEXED_HDR_7;
wsi->u.http2.header_index = c & 0x7f;
+ if ((c & 0x7f) == 0x7f) {
+ wsi->u.http2.hpack_len = c & 0x7f;
+ wsi->u.http2.hpack_m = 0;
+ wsi->u.http2.hpack = HPKS_IDX_EXT;
+ break;
+ }
+ if (lws_add_indexed_hdr(wsi, c & 0x7f))
+ return 1;
/* stay at same state */
break;
}
if (c & 0x40) { /* literal header incr idx */
+ /*
+ * [possibly-extended hdr idx (6) | new literal hdr name]
+ * H + possibly-extended value length
+ * literal value
+ */
+ wsi->u.http2.header_index = 0;
if (c == 0x40) { /* literal name */
- wsi->u.http2.header_index = 0;
- wsi->u.http2.hpack
+ wsi->u.http2.hpack_type = HPKT_LITERAL_HDR_VALUE_INCR;
+ wsi->u.http2.value = 0;
wsi->u.http2.hpack = HPKS_HLEN;
break;
}
/* indexed name */
+ wsi->u.http2.hpack_type = HPKT_INDEXED_HDR_6_VALUE_INCR;
+ if ((c & 0x3f) == 0x3f) {
+ wsi->u.http2.hpack_len = c & 0x3f;
+ wsi->u.http2.hpack_m = 0;
+ wsi->u.http2.hpack = HPKS_IDX_EXT;
+ break;
+ }
wsi->u.http2.header_index = c & 0x3f;
+ wsi->u.http2.value = 1;
wsi->u.http2.hpack = HPKS_HLEN;
break;
}
switch(c & 0xf0) {
+ case 0x10: /* literal header never index */
case 0: /* literal header without indexing */
+ /*
+ * follows 0x40 except 4-bit hdr idx
+ * and don't add to index
+ */
if (c == 0) { /* literal name */
- wsi->u.http2.hpack = HPKS_NAME_HLEN;
+ wsi->u.http2.hpack_type = HPKT_LITERAL_HDR_VALUE;
+ wsi->u.http2.hpack = HPKS_HLEN;
+ wsi->u.http2.value = 0;
break;
}
/* indexed name */
- wsi->u.http2.header_index = c & 0xf;
- wsi->u.http2.hpack = HPKS_VALUE_HLEN;
- break;
- case 0x10: /* literal header never indexed */
- if (c == 0x10) { /* literal name */
- wsi->u.http2.header_index = 0;
- wsi->u.http2.hpack = HPKS_NAME_HLEN;
+ wsi->u.http2.hpack_type = HPKT_INDEXED_HDR_4_VALUE;
+ wsi->u.http2.header_index = 0;
+ if ((c & 0xf) == 0xf) {
+ wsi->u.http2.hpack_len = c & 0xf;
+ wsi->u.http2.hpack_m = 0;
+ wsi->u.http2.hpack = HPKS_IDX_EXT;
break;
}
- /* indexed name */
wsi->u.http2.header_index = c & 0xf;
- wsi->u.http2.hpack = HPKS_NAME_HLEN;
+ wsi->u.http2.value = 1;
+ wsi->u.http2.hpack = HPKS_HLEN;
break;
+
case 0x20:
case 0x30: /* header table size update */
- /* = c & 0x1f */
- /* stay at same state */
+ /* possibly-extended size value (5) */
+ wsi->u.http2.hpack_type = HPKT_SIZE_5;
+ if ((c & 0x1f) == 0x1f) {
+ wsi->u.http2.hpack_len = c & 0x1f;
+ wsi->u.http2.hpack_m = 0;
+ wsi->u.http2.hpack = HPKS_IDX_EXT;
+ break;
+ }
+ lws_hpack_update_table_size(wsi, c & 0x1f);
+ /* stay at HPKS_TYPE state */
break;
}
- break;
- case HPKS_HLEN:
+ break;
+
+ case HPKS_IDX_EXT:
+ wsi->u.http2.hpack_len += (c & 0x7f) << wsi->u.http2.hpack_m;
+ wsi->u.http2.hpack_m += 7;
+ if (!(c & 0x80)) {
+ switch (wsi->u.http2.hpack_type) {
+ case HPKT_INDEXED_HDR_7:
+ if (lws_add_indexed_hdr(wsi, wsi->u.http2.hpack_len))
+ return 1;
+ wsi->u.http2.hpack = HPKS_TYPE;
+ break;
+ default:
+ wsi->u.http2.header_index = wsi->u.http2.hpack_len;
+ wsi->u.http2.value = 1;
+ wsi->u.http2.hpack = HPKS_HLEN;
+ break;
+ }
+ }
+ break;
+
+ case HPKS_HLEN: /* [ H | 7+ ] */
wsi->u.http2.huff = !!(c & 0x80);
+ wsi->u.http2.hpack_pos = 0;
wsi->u.http2.hpack_len = c & 0x7f;
- if (wsi->u.http2.hpack_len < 127) {
- wsi->u.http2.hpack = HPKS_NAME_DATA;
+ if (wsi->u.http2.hpack_len < 0x7f) {
+pre_data:
+ if (wsi->u.http2.value) {
+ if (lws_frag_start(wsi,
+ lws_token_from_index(wsi,
+ wsi->u.http2.header_index)))
+ return 1;
+ } else
+ wsi->u.hdr.parser_state = WSI_TOKEN_NAME_PART;
+ wsi->u.http2.hpack = HPKS_DATA;
break;
}
wsi->u.http2.hpack_m = 0;
- wsi->u.http2.hpack = HPKS_NAME_HLEN_EXT;
+ wsi->u.http2.hpack = HPKS_HLEN_EXT;
break;
+
case HPKS_HLEN_EXT:
- wsi->u.http2.hpack_len += (c & 0x7f) << wsi->u.http2.hpack_m;
+ wsi->u.http2.hpack_len += (c & 0x7f) <<
+ wsi->u.http2.hpack_m;
wsi->u.http2.hpack_m += 7;
if (!(c & 0x80))
- wsi->u.http2.hpack = HPKS_NAME_DATA;
+ goto pre_data;
+
break;
case HPKS_DATA:
+ for (n = 0; n < 8; n++) {
+ if (wsi->u.http2.huff) {
+ prev = wsi->u.http2.hpack_pos;
+ wsi->u.http2.hpack_pos =
+ huftable_decode(
+ wsi->u.http2.hpack_pos,
+ (c >> 7) & 1);
+ c <<= 1;
+ if (wsi->u.http2.hpack_pos == 0xffff)
+ return 1;
+ if (!(wsi->u.http2.hpack_pos & 0x8000))
+ continue;
+ c1 = wsi->u.http2.hpack_pos & 0x7fff;
+ wsi->u.http2.hpack_pos = 0;
+
+ if (!c1 && prev == HUFTABLE_0x100_PREV)
+ ; /* EOT */
+ } else {
+ n = 8;
+ c1 = c;
+ }
+ if (wsi->u.http2.value) { /* value */
+ if (lws_frag_append(wsi, c1))
+ return 1;
+ } else { /* name */
+ if (libwebsocket_parse(context, wsi, c1))
+ return 1;
+
+ }
+ }
+ if (--wsi->u.http2.hpack_len == 0) {
+ n = 8;
+ if (wsi->u.http2.value) {
+ if (lws_frag_end(wsi))
+ return 1;
+ lws_dump_header(wsi, lws_token_from_index(wsi, wsi->u.http2.header_index));
+
+ wsi->u.http2.hpack = HPKS_TYPE;
+ } else { /* name */
+ if (wsi->u.hdr.parser_state < WSI_TOKEN_COUNT)
+
+ wsi->u.http2.value = 1;
+ wsi->u.http2.hpack = HPKS_HLEN;
+ }
+ }
+ break;
}
+
+ return 0;
}