[PATCH] HTTP/2: make http2 server support http1

Haitao Lv i at lvht.net
Wed Mar 21 03:36:08 UTC 2018


Thank you for reviewing.

And here is the patch that fix the breaking PROXY protocol functionality.

Sorry for disturbing.

diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 2db7a627..9f1b8544 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -17,6 +17,10 @@ static ssize_t ngx_http_read_request_header(ngx_http_request_t *r);
 static ngx_int_t ngx_http_alloc_large_header_buffer(ngx_http_request_t *r,
     ngx_uint_t request_line);
 
+#if (NGX_HTTP_V2)
+static void ngx_http_wait_v2_preface_handler(ngx_event_t *rev);
+#endif
+
 static ngx_int_t ngx_http_process_header_line(ngx_http_request_t *r,
     ngx_table_elt_t *h, ngx_uint_t offset);
 static ngx_int_t ngx_http_process_unique_header_line(ngx_http_request_t *r,
@@ -325,7 +329,7 @@ ngx_http_init_connection(ngx_connection_t *c)
 
 #if (NGX_HTTP_V2)
     if (hc->addr_conf->http2) {
-        rev->handler = ngx_http_v2_init;
+        rev->handler = ngx_http_wait_v2_preface_handler;
     }
 #endif
 
@@ -381,6 +385,131 @@ ngx_http_init_connection(ngx_connection_t *c)
 }
 
 
+#if (NGX_HTTP_V2)
+static void
+ngx_http_wait_v2_preface_handler(ngx_event_t *rev)
+{
+    size_t                     size;
+    ssize_t                    n;
+    u_char                    *p;
+    ngx_buf_t                 *b;
+    ngx_connection_t          *c;
+    ngx_http_connection_t     *hc;
+    static const u_char        preface[] = "PRI";
+
+    c = rev->data;
+    hc = c->data;
+
+    size = sizeof(preface) - 1;
+
+    if (hc->proxy_protocol) {
+        size += NGX_PROXY_PROTOCOL_MAX_HEADER;
+    }
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
+            "http wait h2 preface handler");
+
+    if (rev->timedout) {
+        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    if (c->close) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    b = c->buffer;
+
+    if (b == NULL) {
+        b = ngx_create_temp_buf(c->pool, size);
+        if (b == NULL) {
+            ngx_http_close_connection(c);
+            return;
+        }
+
+        c->buffer = b;
+
+    } else if (b->start == NULL) {
+
+        b->start = ngx_palloc(c->pool, size);
+        if (b->start == NULL) {
+            ngx_http_close_connection(c);
+            return;
+        }
+
+        b->pos = b->start;
+        b->last = b->start;
+        b->end = b->last + size;
+    }
+
+    n = c->recv(c, b->last, b->end - b->last);
+
+    if (n == NGX_AGAIN) {
+
+        if (!rev->timer_set) {
+            ngx_add_timer(rev, c->listening->post_accept_timeout);
+            ngx_reusable_connection(c, 1);
+        }
+
+        if (ngx_handle_read_event(rev, 0) != NGX_OK) {
+            ngx_http_close_connection(c);
+            return;
+        }
+
+        /*
+         * We are trying to not hold c->buffer's memory for an idle connection.
+         */
+
+        if (ngx_pfree(c->pool, b->start) == NGX_OK) {
+            b->start = NULL;
+        }
+
+        return;
+    }
+
+    if (n == NGX_ERROR) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    if (n == 0) {
+        ngx_log_error(NGX_LOG_INFO, c->log, 0,
+                      "client closed connection");
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    b->last += n;
+
+    if (hc->proxy_protocol) {
+        hc->proxy_protocol = 0;
+
+        p = ngx_proxy_protocol_read(c, b->pos, b->last);
+
+        if (p == NULL) {
+            ngx_http_close_connection(c);
+            return;
+        }
+
+        b->pos = p;
+    }
+
+    if (b->last >= b->pos + sizeof(preface) - 1) {
+        /* b will be freed in ngx_http_v2_init/ngx_http_wait_request_handler */
+
+        if (ngx_strncmp(b->pos, preface, sizeof(preface) - 1) == 0) {
+            ngx_http_v2_init(rev);
+        } else {
+            rev->handler = ngx_http_wait_request_handler;
+            ngx_http_wait_request_handler(rev);
+        }
+    }
+}
+#endif
+
+
 static void
 ngx_http_wait_request_handler(ngx_event_t *rev)
 {
@@ -393,6 +522,7 @@ ngx_http_wait_request_handler(ngx_event_t *rev)
     ngx_http_core_srv_conf_t  *cscf;
 
     c = rev->data;
+    n = NGX_AGAIN;
 
     ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http wait request handler");
 
@@ -434,9 +564,27 @@ ngx_http_wait_request_handler(ngx_event_t *rev)
         b->pos = b->start;
         b->last = b->start;
         b->end = b->last + size;
+    } else {
+
+        p = ngx_palloc(c->pool, size);
+        if (p == NULL) {
+            ngx_http_close_connection(c);
+            return;
+        }
+
+        n = b->last - b->pos;
+        ngx_memcpy(p, b->pos, n);
+        ngx_pfree(c->pool, b->start);
+
+        b->start = p;
+        b->pos = b->start;
+        b->last = b->start + n;
+        b->end = b->last + size;
     }
 
-    n = c->recv(c, b->last, size);
+    if (n == NGX_AGAIN) {
+        n = c->recv(c, b->last, size);
+    }
 
     if (n == NGX_AGAIN) {
 
diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c
index 77ebb847..6724b662 100644
--- a/src/http/v2/ngx_http_v2.c
+++ b/src/http/v2/ngx_http_v2.c
@@ -229,6 +229,8 @@ static ngx_http_v2_parse_header_t  ngx_http_v2_parse_headers[] = {
 void
 ngx_http_v2_init(ngx_event_t *rev)
 {
+    size_t                     size;
+    ngx_buf_t                 *b;
     ngx_connection_t          *c;
     ngx_pool_cleanup_t        *cln;
     ngx_http_connection_t     *hc;
@@ -260,6 +262,23 @@ ngx_http_v2_init(ngx_event_t *rev)
         return;
     }
 
+    b = c->buffer;
+
+    if (b != NULL) {
+        size = b->last - b->pos;
+
+        if (size > h2mcf->recv_buffer_size) {
+            size = h2mcf->recv_buffer_size;
+        }
+
+        ngx_memcpy(h2mcf->recv_buffer, b->pos, size);
+        h2c->state.buffer_used = size;
+
+        ngx_pfree(c->pool, b->start);
+        ngx_pfree(c->pool, b);
+        c->buffer = NULL;
+    }
+
     h2c->connection = c;
     h2c->http_connection = hc;
 
@@ -379,13 +398,15 @@ ngx_http_v2_read_handler(ngx_event_t *rev)
     h2mcf = ngx_http_get_module_main_conf(h2c->http_connection->conf_ctx,
                                           ngx_http_v2_module);
 
-    available = h2mcf->recv_buffer_size - 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE;
+    available = h2mcf->recv_buffer_size - h2c->state.buffer_used - 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE;
 
     do {
         p = h2mcf->recv_buffer;
 
-        ngx_memcpy(p, h2c->state.buffer, NGX_HTTP_V2_STATE_BUFFER_SIZE);
         end = p + h2c->state.buffer_used;
+        if (h2c->state.buffer_used == 0) {
+            ngx_memcpy(p, h2c->state.buffer, NGX_HTTP_V2_STATE_BUFFER_SIZE);
+        }
 
         n = c->recv(c, end, available);
 


> On Mar 21, 2018, at 00:02, Valentin V. Bartenev <vbart at nginx.com> wrote:
> 
> On Thursday 08 March 2018 08:42:27 Haitao Lv wrote:
>> Sorry for disturbing. But I have to fix a buffer overflow bug.
>> Here is the latest patch.
>> 
>> Sorry. But please make your comments. Thank you.
> [..]
> 
> There's no way for this patch to be accepted as it breaks PROXY protocol
> functionality.
> 
>  wbr, Valentin V. Bartenev
> 
> _______________________________________________
> nginx-devel mailing list
> nginx-devel at nginx.org
> http://mailman.nginx.org/mailman/listinfo/nginx-devel





More information about the nginx-devel mailing list