diff options
Diffstat (limited to 'src/http.c')
| -rw-r--r-- | src/http.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/src/http.c b/src/http.c new file mode 100644 index 0000000..1b78911 --- /dev/null +++ b/src/http.c @@ -0,0 +1,271 @@ +#include <libwebsockets.h> +#include <string.h> +#include <zlib.h> + +#include "html.h" +#include "server.h" +#include "utils.h" + +#if LWS_LIBRARY_VERSION_MAJOR < 2 +#define HTTP_STATUS_FOUND 302 +#endif + +enum { AUTH_OK, AUTH_FAIL, AUTH_ERROR }; + +static char *html_cache = NULL; +static size_t html_cache_len = 0; + +static int check_auth(struct lws *wsi, struct pss_http *pss) { + if (server->credential == NULL) return AUTH_OK; + + int hdr_length = lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_AUTHORIZATION); + char buf[hdr_length + 1]; + int len = lws_hdr_copy(wsi, buf, sizeof(buf), WSI_TOKEN_HTTP_AUTHORIZATION); + if (len > 0) { + // extract base64 text from authorization header + char *ptr = &buf[0]; + char *token, *b64_text = NULL; + int i = 1; + while ((token = strsep(&ptr, " ")) != NULL) { + if (strlen(token) == 0) continue; + if (i++ == 2) { + b64_text = token; + break; + } + } + if (b64_text != NULL && !strcmp(b64_text, server->credential)) return AUTH_OK; + } + + unsigned char buffer[1024 + LWS_PRE], *p, *end; + p = buffer + LWS_PRE; + end = p + sizeof(buffer) - LWS_PRE; + + char *body = strdup("401 Unauthorized\n"); + size_t n = strlen(body); + + if (lws_add_http_header_status(wsi, HTTP_STATUS_UNAUTHORIZED, &p, end) || + lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_WWW_AUTHENTICATE, + (unsigned char *)"Basic realm=\"ttyd\"", 18, &p, end) || + lws_add_http_header_content_length(wsi, n, &p, end) || + lws_finalize_http_header(wsi, &p, end) || + lws_write(wsi, buffer + LWS_PRE, p - (buffer + LWS_PRE), LWS_WRITE_HTTP_HEADERS) < 0) + return AUTH_ERROR; + + pss->buffer = pss->ptr = body; + pss->len = n; + lws_callback_on_writable(wsi); + + return AUTH_FAIL; +} + +static bool accept_gzip(struct lws *wsi) { + int hdr_length = lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_ACCEPT_ENCODING); + char buf[hdr_length + 1]; + int len = lws_hdr_copy(wsi, buf, sizeof(buf), WSI_TOKEN_HTTP_ACCEPT_ENCODING); + return len > 0 && strstr(buf, "gzip") != NULL; +} + +static bool uncompress_html(char **output, size_t *output_len) { + if (html_cache == NULL || html_cache_len == 0) { + z_stream stream; + memset(&stream, 0, sizeof(stream)); + if (inflateInit2(&stream, 16 + 15) != Z_OK) return false; + + html_cache_len = index_html_size; + html_cache = xmalloc(html_cache_len); + + stream.avail_in = index_html_len; + stream.avail_out = html_cache_len; + stream.next_in = (void *)index_html; + stream.next_out = (void *)html_cache; + + int ret = inflate(&stream, Z_SYNC_FLUSH); + inflateEnd(&stream); + if (ret != Z_STREAM_END) { + free(html_cache); + html_cache = NULL; + html_cache_len = 0; + return false; + } + } + + *output = html_cache; + *output_len = html_cache_len; + + return true; +} + +static void pss_buffer_free(struct pss_http *pss) { + if (pss->buffer != (char *)index_html && pss->buffer != html_cache) free(pss->buffer); +} + +static void access_log(struct lws *wsi, const char *path) { + char rip[50]; + +#if LWS_LIBRARY_VERSION_NUMBER >= 2004000 + lws_get_peer_simple(lws_get_network_wsi(wsi), rip, sizeof(rip)); +#else + char name[100]; + lws_get_peer_addresses(wsi, lws_get_socket_fd(wsi), name, sizeof(name), rip, sizeof(rip)); +#endif + lwsl_notice("HTTP %s - %s\n", path, rip); +} + +int callback_http(struct lws *wsi, enum lws_callback_reasons reason, void *user, void *in, + size_t len) { + struct pss_http *pss = (struct pss_http *)user; + unsigned char buffer[4096 + LWS_PRE], *p, *end; + char buf[256]; + bool done = false; + + switch (reason) { + case LWS_CALLBACK_HTTP: + access_log(wsi, (const char *)in); + snprintf(pss->path, sizeof(pss->path), "%s", (const char *)in); + switch (check_auth(wsi, pss)) { + case AUTH_OK: + break; + case AUTH_FAIL: + return 0; + case AUTH_ERROR: + default: + return 1; + } + + p = buffer + LWS_PRE; + end = p + sizeof(buffer) - LWS_PRE; + + if (strcmp(pss->path, endpoints.token) == 0) { + const char *credential = server->credential != NULL ? server->credential : ""; + size_t n = sprintf(buf, "{\"token\": \"%s\"}", credential); + if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end) || + lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE, + (unsigned char *)"application/json;charset=utf-8", 30, &p, + end) || + lws_add_http_header_content_length(wsi, (unsigned long)n, &p, end) || + lws_finalize_http_header(wsi, &p, end) || + lws_write(wsi, buffer + LWS_PRE, p - (buffer + LWS_PRE), LWS_WRITE_HTTP_HEADERS) < 0) + return 1; + + pss->buffer = pss->ptr = strdup(buf); + pss->len = n; + lws_callback_on_writable(wsi); + break; + } + + // redirects `/base-path` to `/base-path/` + if (strcmp(pss->path, endpoints.parent) == 0) { + if (lws_add_http_header_status(wsi, HTTP_STATUS_FOUND, &p, end) || + lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_LOCATION, + (unsigned char *)endpoints.index, + (int)strlen(endpoints.index), &p, end) || + lws_add_http_header_content_length(wsi, 0, &p, end) || + lws_finalize_http_header(wsi, &p, end) || + lws_write(wsi, buffer + LWS_PRE, p - (buffer + LWS_PRE), LWS_WRITE_HTTP_HEADERS) < 0) + return 1; + goto try_to_reuse; + } + + if (strcmp(pss->path, endpoints.index) != 0) { + lws_return_http_status(wsi, HTTP_STATUS_NOT_FOUND, NULL); + goto try_to_reuse; + } + + const char *content_type = "text/html"; + if (server->index != NULL) { + int n = lws_serve_http_file(wsi, server->index, content_type, NULL, 0); + if (n < 0 || (n > 0 && lws_http_transaction_completed(wsi))) return 1; + } else { + char *output = (char *)index_html; + size_t output_len = index_html_len; + if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end) || + lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE, + (const unsigned char *)content_type, 9, &p, end)) + return 1; +#ifdef LWS_WITH_HTTP_STREAM_COMPRESSION + if (!uncompress_html(&output, &output_len)) return 1; +#else + if (accept_gzip(wsi)) { + if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_ENCODING, + (unsigned char *)"gzip", 4, &p, end)) + return 1; + } else { + if (!uncompress_html(&output, &output_len)) return 1; + } +#endif + + if (lws_add_http_header_content_length(wsi, (unsigned long)output_len, &p, end) || + lws_finalize_http_header(wsi, &p, end) || + lws_write(wsi, buffer + LWS_PRE, p - (buffer + LWS_PRE), LWS_WRITE_HTTP_HEADERS) < 0) + return 1; + +#if LWS_LIBRARY_VERSION_MAJOR < 2 + if (lws_write_http(wsi, output, output_len) < 0) return 1; + goto try_to_reuse; +#else + pss->buffer = pss->ptr = output; + pss->len = output_len; + lws_callback_on_writable(wsi); +#endif + } + break; + + case LWS_CALLBACK_HTTP_WRITEABLE: + if (!pss->buffer || pss->len == 0) { + goto try_to_reuse; + } + + do { + int n = sizeof(buffer) - LWS_PRE; + int m = lws_get_peer_write_allowance(wsi); + if (m == 0) { + lws_callback_on_writable(wsi); + return 0; + } else if (m != -1 && m < n) { + n = m; + } + if (pss->ptr + n > pss->buffer + pss->len) { + n = (int)(pss->len - (pss->ptr - pss->buffer)); + done = true; + } + memcpy(buffer + LWS_PRE, pss->ptr, n); + pss->ptr += n; + if (lws_write_http(wsi, buffer + LWS_PRE, (size_t)n) < n) { + pss_buffer_free(pss); + return -1; + } + } while (!lws_send_pipe_choked(wsi) && !done); + + if (!done && pss->ptr < pss->buffer + pss->len) { + lws_callback_on_writable(wsi); + break; + } + + pss_buffer_free(pss); + goto try_to_reuse; + + case LWS_CALLBACK_HTTP_FILE_COMPLETION: + goto try_to_reuse; +#if (defined(LWS_OPENSSL_SUPPORT) || defined(LWS_WITH_TLS)) && !defined(LWS_WITH_MBEDTLS) + case LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION: + if (!len || (SSL_get_verify_result((SSL *)in) != X509_V_OK)) { + int err = X509_STORE_CTX_get_error((X509_STORE_CTX *)user); + int depth = X509_STORE_CTX_get_error_depth((X509_STORE_CTX *)user); + const char *msg = X509_verify_cert_error_string(err); + lwsl_err("client certificate verification error: %s (%d), depth: %d\n", msg, err, depth); + return 1; + } + break; +#endif + default: + break; + } + + return 0; + + /* if we're on HTTP1.1 or 2.0, will keep the idle connection alive */ +try_to_reuse: + if (lws_http_transaction_completed(wsi)) return -1; + + return 0; +} |