Skip to content

Commit 0245c5c

Browse files
bryghtlabs-richardbryghtlabs-richard
committed
feat(transport_ws): add header callback hook
Move to a line-by-line header parser. Support a callback hook for each header-line. Migrate "Location" and "Sec-WebSocket-Accept" parsing. Part of espressif/esp-protocols#715
1 parent 7629d08 commit 0245c5c

File tree

2 files changed

+115
-46
lines changed

2 files changed

+115
-46
lines changed

‎components/tcp_transport/include/esp_transport_ws.h‎

Lines changed: 29 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -29,6 +29,8 @@ typedef enum ws_transport_opcodes {
2929
* from the API esp_transport_ws_get_read_opcode() */
3030
} ws_transport_opcodes_t;
3131

32+
typedef void (*ws_header_hook)(void * userp, const char * line, int line_len);
33+
3234
/**
3335
* WS transport configuration structure
3436
*/
@@ -37,6 +39,8 @@ typedef struct {
3739
const char *sub_protocol; /*!< WS subprotocol */
3840
const char *user_agent; /*!< WS user agent */
3941
const char *headers; /*!< WS additional headers */
42+
ws_header_hook header_hook; /*!< WS received header */
43+
void *header_userp; /*!< WS received header user-pointer */
4044
const char *auth; /*!< HTTP authorization header */
4145
char *response_headers; /*!< The buffer to copy the http response header */
4246
size_t response_headers_len; /*!< The length of the http response header */
@@ -99,6 +103,31 @@ esp_err_t esp_transport_ws_set_user_agent(esp_transport_handle_t t, const char *
99103
*/
100104
esp_err_t esp_transport_ws_set_headers(esp_transport_handle_t t, const char *headers);
101105

106+
/**
107+
* @brief Set websocket header callback
108+
*
109+
* @param t websocket transport handle
110+
* @param hook call function on header received. NULL to disable.
111+
*
112+
* @return
113+
* - ESP_OK on success
114+
* - One of the error codes
115+
*/
116+
esp_err_t esp_transport_ws_set_header_hook(esp_transport_handle_t t, ws_header_hook hook);
117+
118+
119+
/**
120+
* @brief Set websocket header callback user-pointer
121+
*
122+
* @param t websocket transport handle
123+
* @param userp caller-controlled argument to ws_header_hook
124+
*
125+
* @return
126+
* - ESP_OK on success
127+
* - One of the error codes
128+
*/
129+
esp_err_t esp_transport_ws_set_header_userp(esp_transport_handle_t t, void * userp);
130+
102131
/**
103132
* @brief Set websocket authorization headers
104133
*

‎components/tcp_transport/transport_ws.c‎

Lines changed: 86 additions & 46 deletions
Original file line numberDiff line numberDiff line change
@@ -63,6 +63,8 @@ typedef struct {
6363
char *sub_protocol;
6464
char *user_agent;
6565
char *headers;
66+
ws_header_hook header_hook;
67+
void * header_userp;
6668
char *auth;
6769
char *buffer; /*!< Initial HTTP connection buffer, which may include data beyond the handshake headers, such as the next WebSocket packet*/
6870
size_t buffer_len; /*!< The buffer length */
@@ -144,31 +146,6 @@ static int esp_transport_read_internal(transport_ws_t *ws, char *buffer, int len
144146
return to_read;
145147
}
146148

147-
static char *trimwhitespace(char *str)
148-
{
149-
char *end;
150-
151-
// Trim leading space
152-
while (isspace((unsigned char)*str)) {
153-
str++;
154-
}
155-
156-
if (*str == 0) {
157-
return str;
158-
}
159-
160-
// Trim trailing space
161-
end = str + strlen(str) - 1;
162-
while (end > str && isspace((unsigned char)*end)) {
163-
end--;
164-
}
165-
166-
// Write new null terminator
167-
*(end + 1) = '\0';
168-
169-
return str;
170-
}
171-
172149
static int get_http_status_code(const char *buffer)
173150
{
174151
const char http[] = "HTTP/";
@@ -189,21 +166,6 @@ static int get_http_status_code(const char *buffer)
189166
return -1;
190167
}
191168

192-
static char *get_http_header(char *buffer, const char *key)
193-
{
194-
char *found = strcasestr(buffer, key);
195-
if (found) {
196-
found += strlen(key);
197-
char *found_end = strstr(found, "\r\n");
198-
if (found_end) {
199-
*found_end = '\0'; // terminal string
200-
201-
return trimwhitespace(found);
202-
}
203-
}
204-
return NULL;
205-
}
206-
207169
static int ws_connect(esp_transport_handle_t t, const char *host, int port, int timeout_ms)
208170
{
209171
transport_ws_t *ws = esp_transport_get_context_data(t);
@@ -330,17 +292,67 @@ static int ws_connect(esp_transport_handle_t t, const char *host, int port, int
330292
if (ws->http_status_code == -1) {
331293
ESP_LOGE(TAG, "HTTP upgrade failed");
332294
return -1;
333-
} else if (WS_HTTP_TEMPORARY_REDIRECT(ws->http_status_code) || WS_HTTP_PERMANENT_REDIRECT(ws->http_status_code)) {
334-
char * redir_host = get_http_header(ws->buffer, "Location:");
335-
if (redir_host == NULL) {
295+
}
296+
297+
const char *location = NULL;
298+
int location_len = 0;
299+
300+
const char *server_key = NULL;
301+
int server_key_len = 0;
302+
const char * header_cursor = strnstr(ws->buffer, "\r\n", header_len);
303+
if (!header_cursor){
304+
ESP_LOGE(TAG, "HTTP Header locate failed");
305+
return -1;
306+
}
307+
header_cursor += strlen("\r\n");
308+
309+
while(header_cursor < delim_ptr){
310+
const char * end_of_line = strnstr(header_cursor, "\r\n", header_len - (header_cursor - ws->buffer));
311+
if(!end_of_line){
312+
ESP_LOGE(TAG, "HTTP Header walk failed");
313+
return -1;
314+
}
315+
else if(end_of_line == header_cursor){
316+
ESP_LOGD(TAG, "HTTP Header walk found end");
317+
break;
318+
}
319+
int line_len = end_of_line - header_cursor;
320+
ESP_LOGD(TAG, "HTTP Header walk line:%.*s", line_len, header_cursor);
321+
322+
// Check for Sec-WebSocket-Accept header
323+
const char * header_sec_websocket_accept = "Sec-WebSocket-Accept: ";
324+
size_t header_sec_websocket_accept_len = strlen(header_sec_websocket_accept);
325+
if (line_len >= header_sec_websocket_accept_len && !strncasecmp(header_cursor, header_sec_websocket_accept, header_sec_websocket_accept_len)) {
326+
ESP_LOGD(TAG, "found server-key");
327+
server_key = header_cursor + header_sec_websocket_accept_len;
328+
server_key_len = line_len - header_sec_websocket_accept_len;
329+
}
330+
else if (ws->header_hook) {
331+
ws->header_hook(ws->header_userp, header_cursor, line_len);
332+
}
333+
334+
// Check for Location: header
335+
const char * header_location = "Location: ";
336+
size_t header_location_len = strlen(header_location);
337+
if (line_len >= header_location_len && !strncasecmp(header_cursor, header_location, header_location_len)) {
338+
location = header_cursor + header_location_len;
339+
location_len = line_len - header_location_len;
340+
}
341+
342+
// Adjust cursor to the start of the next line
343+
header_cursor += line_len;
344+
header_cursor += strlen("\r\n");
345+
}
346+
347+
if (WS_HTTP_TEMPORARY_REDIRECT(ws->http_status_code) || WS_HTTP_PERMANENT_REDIRECT(ws->http_status_code)) {
348+
if (location == NULL || location_len <= 0) {
336349
ESP_LOGE(TAG, "Location header not found");
337350
return -1;
338351
}
339-
ws->redir_host = strdup(redir_host);
352+
ws->redir_host = strndup(location, location_len);
340353
return ws->http_status_code;
341354
}
342355

343-
char *server_key = get_http_header(ws->buffer, "Sec-WebSocket-Accept:");
344356
if (server_key == NULL) {
345357
ESP_LOGE(TAG, "Sec-WebSocket-Accept not found");
346358
return -1;
@@ -361,7 +373,7 @@ static int ws_connect(esp_transport_handle_t t, const char *host, int port, int
361373
esp_crypto_base64_encode(expected_server_key, sizeof(expected_server_key), &outlen, expected_server_sha1, sizeof(expected_server_sha1));
362374
expected_server_key[ (outlen < sizeof(expected_server_key)) ? outlen : (sizeof(expected_server_key) - 1) ] = 0;
363375
ESP_LOGD(TAG, "server key=%s, send_key=%s, expected_server_key=%s", (char *)server_key, (char *)client_key, expected_server_key);
364-
if (strcmp((char *)expected_server_key, (char *)server_key) != 0) {
376+
if (strncmp((char *)expected_server_key, (char *)server_key, server_key_len) != 0) {
365377
ESP_LOGE(TAG, "Invalid websocket key");
366378
return -1;
367379
}
@@ -866,6 +878,26 @@ esp_err_t esp_transport_ws_set_headers(esp_transport_handle_t t, const char *hea
866878
return ESP_OK;
867879
}
868880

881+
esp_err_t esp_transport_ws_set_header_hook(esp_transport_handle_t t, ws_header_hook hook)
882+
{
883+
if (t == NULL) {
884+
return ESP_ERR_INVALID_ARG;
885+
}
886+
transport_ws_t *ws = esp_transport_get_context_data(t);
887+
ws->header_hook = hook;
888+
return ESP_OK;
889+
}
890+
891+
esp_err_t esp_transport_ws_set_header_userp(esp_transport_handle_t t, void * userp)
892+
{
893+
if (t == NULL) {
894+
return ESP_ERR_INVALID_ARG;
895+
}
896+
transport_ws_t *ws = esp_transport_get_context_data(t);
897+
ws->header_userp = userp;
898+
return ESP_OK;
899+
}
900+
869901
esp_err_t esp_transport_ws_set_auth(esp_transport_handle_t t, const char *auth)
870902
{
871903
if (t == NULL) {
@@ -931,6 +963,14 @@ esp_err_t esp_transport_ws_set_config(esp_transport_handle_t t, const esp_transp
931963
err = esp_transport_ws_set_headers(t, config->headers);
932964
ESP_TRANSPORT_ERR_OK_CHECK(TAG, err, return err;)
933965
}
966+
if (config->header_hook) {
967+
err = esp_transport_ws_set_header_hook(t, config->header_hook);
968+
ESP_TRANSPORT_ERR_OK_CHECK(TAG, err, return err;)
969+
}
970+
if (config->header_userp) {
971+
err = esp_transport_ws_set_header_userp(t, config->header_userp);
972+
ESP_TRANSPORT_ERR_OK_CHECK(TAG, err, return err;)
973+
}
934974
if (config->auth) {
935975
err = esp_transport_ws_set_auth(t, config->auth);
936976
ESP_TRANSPORT_ERR_OK_CHECK(TAG, err, return err;)

0 commit comments

Comments
 (0)