int try_upgrade(request_t *req, connection_t *con)
{
// Does it contain "Upgrade: websocket"?
// TODO: Also needs "Connection: Upgrade"
// TODO: 'websocket' match is case insensitive.
char *upgrade = request_get_header(req, "Upgrade");
if (upgrade == NULL || strcmp(upgrade, "websocket")) {
// Not an upgrade.
return 0;
}
char *version = request_get_header(req, "Sec-WebSocket-Version");
if (strcmp(version, "8") && strcmp(version, "13")) {
printf("Wrong WebSocket version! %s, expecting 8 or 13.\n", version);
return 0;
}
char iv[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
char *key = request_get_header(req, "Sec-WebSocket-Key");
char concat[80]; // TODO: exact length?
strcpy(concat, key);
strcat(concat, iv);
char *hash = (char *) SHA1((unsigned char *)concat, strlen(concat), NULL);
BIO *b64 = BIO_new(BIO_f_base64());
BIO *bmem = BIO_new(BIO_s_mem());
BIO_push(b64, bmem);
BIO_write(b64, hash, 20);
if (BIO_flush(b64) != 1) perror("BIO_flush");
BUF_MEM *bptr;
BIO_get_mem_ptr(b64, &bptr);
char *hash_enc = malloc(bptr->length);
memcpy(hash_enc, bptr->data, bptr->length);
hash_enc[bptr->length - 1] = 0;
char msg_f[] =
"HTTP/1.1 101 Switching Protocols\r\n"
"Connection: Upgrade\r\n"
"Upgrade: websocket\r\n"
"Sec-WebSocket-Accept: %s\r\n\r\n";
// hash_enc is 28 bytes long, replacing '%s'...
char *msg = malloc(strlen(msg_f) + (28-2));
sprintf(msg, msg_f, hash_enc);
socket_write(con->socket, msg, strlen(msg));
BIO_free_all(b64);
con->is_websocket = 1;
return 1;
}
static int handle_cache(request_t *req, response_t *resp,
const struct stat *st, const mod_static_conf_t *conf) {
const char *if_mod_since, *if_none_match;
char *etag;
time_t mtime, req_mtime;
int not_modified = 0;
char *buf;
char *cache_control;
mtime = st->st_mtime;
if_mod_since = request_get_header(req, "if-modified-since");
if (if_mod_since != NULL &&
parse_http_date(if_mod_since, &req_mtime) == 0 &&
req_mtime == mtime) {
debug("Resource not modified");
not_modified = 1;
}
buf = response_alloc(resp, 32);
format_http_date(&mtime, buf, 32);
response_set_header(resp, "Last-Modified", buf);
if (conf->enable_etag) {
etag = generate_etag(st);
if (not_modified) {
if_none_match = request_get_header(req, "if-none-match");
if (if_none_match == NULL ||
strcmp(etag, if_none_match) != 0) {
not_modified = 0;
}
}
response_set_header(resp, "ETag", etag);
}
if (conf->expire_hours >= 0) {
buf = response_alloc(resp, 32);
mtime += conf->expire_hours * 3600;
format_http_date(&mtime, buf, 32);
response_set_header(resp, "Expires", buf);
cache_control = response_alloc(resp, 20);
snprintf(cache_control, 20, "max-age=%d", conf->expire_hours * 3600);
} else {
cache_control = "no-cache";
}
response_set_header(resp, "Cache-Control", cache_control);
return not_modified;
}
/*
* Return values:
* 0: valid range request
* 1: range not satisfiable (should return 416)
* -1: syntactically invalid range (ignore, return full content)
*/
static int handle_range(request_t *req, response_t *resp,
size_t *offset, size_t *size) {
const char *range_spec;
char buf[100], *pos;
size_t len, total_size = *size, off, sz, end;
int idx;
range_spec = request_get_header(req, "range");
if (range_spec == NULL) {
return -1;
}
len = strlen(range_spec);
if (len < 8) {
return -1;
}
if (strstr(range_spec, "bytes=") != range_spec) {
error("Only byte ranges are supported(error range:%s)", range_spec);
return -1;
}
strncpy(buf, range_spec + 6, 100);
len = strlen(buf);
if (index(buf, ',') != NULL) {
error("Multiple ranges are not supported.");
return -1;
}
pos = index(buf, '-');
if (pos == NULL) {
error("Invalid range spec: %s.", range_spec);
return -1;
}
idx = pos - buf;
if (idx == 0) {
sz = atol(buf + 1);
end = total_size;
off = total_size - sz;
} else if (idx == len - 1) {
buf[idx] = '\0';
off = atol(buf);
end = total_size;
sz = total_size - off;
} else {
buf[idx] = '\0';
off = atol(buf);
end = atol(buf + idx + 1);
sz = end - off + 1;
}
if (end < off)
return -1;
if (off >= total_size || sz > total_size)
return 1;
response_set_header_printf(resp, "Content-Range", "bytes %ld-%ld/%ld",
off, off + sz - 1, total_size);
*offset = off;
*size = sz;
return 0;
}
