Mercurial > hg > nginx
view src/http/v3/ngx_http_v3_filter_module.c @ 9112:d59277dd3d8c
QUIC: fixed post-close use-after-free.
Previously, ngx_quic_close_connection() could be called in a way that QUIC
connection was accessed after the call. In most cases the connection is not
closed right away, but close timeout is scheduled. However, it's not always
the case. Also, if the close process started earlier for a different reason,
calling ngx_quic_close_connection() may actually close the connection. The
connection object should not be accessed after that.
Now, when possible, return statement is added to eliminate post-close connection
object access. In other places ngx_quic_close_connection() is substituted with
posting close event.
Also, the new way of closing connection in ngx_quic_stream_cleanup_handler()
fixes another problem in this function. Previously it passed stream connection
instead of QUIC connection to ngx_quic_close_connection(). This could result
in incomplete connection shutdown. One consequence of that could be that QUIC
streams were freed without shutting down their application contexts. This could
result in another use-after-free.
Found by Coverity (CID 1530402).
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 22 May 2023 15:59:42 +0400 |
parents | f742b1b46901 |
children | f91dc350be9f |
line wrap: on
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/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> /* static table indices */ #define NGX_HTTP_V3_HEADER_AUTHORITY 0 #define NGX_HTTP_V3_HEADER_PATH_ROOT 1 #define NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO 4 #define NGX_HTTP_V3_HEADER_DATE 6 #define NGX_HTTP_V3_HEADER_LAST_MODIFIED 10 #define NGX_HTTP_V3_HEADER_LOCATION 12 #define NGX_HTTP_V3_HEADER_METHOD_GET 17 #define NGX_HTTP_V3_HEADER_SCHEME_HTTP 22 #define NGX_HTTP_V3_HEADER_SCHEME_HTTPS 23 #define NGX_HTTP_V3_HEADER_STATUS_200 25 #define NGX_HTTP_V3_HEADER_ACCEPT_ENCODING 31 #define NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN 53 #define NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING 59 #define NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE 72 #define NGX_HTTP_V3_HEADER_SERVER 92 #define NGX_HTTP_V3_HEADER_USER_AGENT 95 typedef struct { ngx_chain_t *free; ngx_chain_t *busy; } ngx_http_v3_filter_ctx_t; static ngx_int_t ngx_http_v3_header_filter(ngx_http_request_t *r); static ngx_int_t ngx_http_v3_body_filter(ngx_http_request_t *r, ngx_chain_t *in); static ngx_chain_t *ngx_http_v3_create_trailers(ngx_http_request_t *r, ngx_http_v3_filter_ctx_t *ctx); static ngx_int_t ngx_http_v3_filter_init(ngx_conf_t *cf); static ngx_http_module_t ngx_http_v3_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_v3_filter_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_v3_filter_module = { NGX_MODULE_V1, &ngx_http_v3_filter_module_ctx, /* module context */ NULL, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_http_output_header_filter_pt ngx_http_next_header_filter; static ngx_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_int_t ngx_http_v3_header_filter(ngx_http_request_t *r) { u_char *p; size_t len, n; ngx_buf_t *b; ngx_str_t host, location; ngx_uint_t i, port; ngx_chain_t *out, *hl, *cl, **ll; ngx_list_part_t *part; ngx_table_elt_t *header; ngx_connection_t *c; ngx_http_v3_session_t *h3c; ngx_http_v3_filter_ctx_t *ctx; ngx_http_core_loc_conf_t *clcf; ngx_http_core_srv_conf_t *cscf; u_char addr[NGX_SOCKADDR_STRLEN]; if (r->http_version != NGX_HTTP_VERSION_30) { return ngx_http_next_header_filter(r); } if (r->header_sent) { return NGX_OK; } r->header_sent = 1; if (r != r->main) { return NGX_OK; } h3c = ngx_http_v3_get_session(r->connection); if (r->method == NGX_HTTP_HEAD) { r->header_only = 1; } if (r->headers_out.last_modified_time != -1) { if (r->headers_out.status != NGX_HTTP_OK && r->headers_out.status != NGX_HTTP_PARTIAL_CONTENT && r->headers_out.status != NGX_HTTP_NOT_MODIFIED) { r->headers_out.last_modified_time = -1; r->headers_out.last_modified = NULL; } } if (r->headers_out.status == NGX_HTTP_NO_CONTENT) { r->header_only = 1; ngx_str_null(&r->headers_out.content_type); r->headers_out.last_modified_time = -1; r->headers_out.last_modified = NULL; r->headers_out.content_length = NULL; r->headers_out.content_length_n = -1; } if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED) { r->header_only = 1; } c = r->connection; out = NULL; ll = &out; len = ngx_http_v3_encode_field_section_prefix(NULL, 0, 0, 0); if (r->headers_out.status == NGX_HTTP_OK) { len += ngx_http_v3_encode_field_ri(NULL, 0, NGX_HTTP_V3_HEADER_STATUS_200); } else { len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_STATUS_200, NULL, 3); } clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); if (r->headers_out.server == NULL) { if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) { n = sizeof(NGINX_VER) - 1; } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) { n = sizeof(NGINX_VER_BUILD) - 1; } else { n = sizeof("nginx") - 1; } len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_SERVER, NULL, n); } if (r->headers_out.date == NULL) { len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_DATE, NULL, ngx_cached_http_time.len); } if (r->headers_out.content_type.len) { n = r->headers_out.content_type.len; if (r->headers_out.content_type_len == r->headers_out.content_type.len && r->headers_out.charset.len) { n += sizeof("; charset=") - 1 + r->headers_out.charset.len; } len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN, NULL, n); } if (r->headers_out.content_length == NULL) { if (r->headers_out.content_length_n > 0) { len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO, NULL, NGX_OFF_T_LEN); } else if (r->headers_out.content_length_n == 0) { len += ngx_http_v3_encode_field_ri(NULL, 0, NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO); } } if (r->headers_out.last_modified == NULL && r->headers_out.last_modified_time != -1) { len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_LAST_MODIFIED, NULL, sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1); } if (r->headers_out.location && r->headers_out.location->value.len) { if (r->headers_out.location->value.data[0] == '/' && clcf->absolute_redirect) { if (clcf->server_name_in_redirect) { cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module); host = cscf->server_name; } else if (r->headers_in.server.len) { host = r->headers_in.server; } else { host.len = NGX_SOCKADDR_STRLEN; host.data = addr; if (ngx_connection_local_sockaddr(c, &host, 0) != NGX_OK) { return NGX_ERROR; } } port = ngx_inet_get_port(c->local_sockaddr); location.len = sizeof("https://") - 1 + host.len + r->headers_out.location->value.len; if (clcf->port_in_redirect) { port = (port == 443) ? 0 : port; } else { port = 0; } if (port) { location.len += sizeof(":65535") - 1; } location.data = ngx_pnalloc(r->pool, location.len); if (location.data == NULL) { return NGX_ERROR; } p = ngx_cpymem(location.data, "https://", sizeof("https://") - 1); p = ngx_cpymem(p, host.data, host.len); if (port) { p = ngx_sprintf(p, ":%ui", port); } p = ngx_cpymem(p, r->headers_out.location->value.data, r->headers_out.location->value.len); /* update r->headers_out.location->value for possible logging */ r->headers_out.location->value.len = p - location.data; r->headers_out.location->value.data = location.data; ngx_str_set(&r->headers_out.location->key, "Location"); } r->headers_out.location->hash = 0; len += ngx_http_v3_encode_field_lri(NULL, 0, NGX_HTTP_V3_HEADER_LOCATION, NULL, r->headers_out.location->value.len); } #if (NGX_HTTP_GZIP) if (r->gzip_vary) { if (clcf->gzip_vary) { len += ngx_http_v3_encode_field_ri(NULL, 0, NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING); } else { r->gzip_vary = 0; } } #endif part = &r->headers_out.headers.part; header = part->elts; for (i = 0; /* void */; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (header[i].hash == 0) { continue; } len += ngx_http_v3_encode_field_l(NULL, &header[i].key, &header[i].value); } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 header len:%uz", len); b = ngx_create_temp_buf(r->pool, len); if (b == NULL) { return NGX_ERROR; } b->last = (u_char *) ngx_http_v3_encode_field_section_prefix(b->last, 0, 0, 0); ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \":status: %03ui\"", r->headers_out.status); if (r->headers_out.status == NGX_HTTP_OK) { b->last = (u_char *) ngx_http_v3_encode_field_ri(b->last, 0, NGX_HTTP_V3_HEADER_STATUS_200); } else { b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_STATUS_200, NULL, 3); b->last = ngx_sprintf(b->last, "%03ui", r->headers_out.status); } if (r->headers_out.server == NULL) { if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) { p = (u_char *) NGINX_VER; n = sizeof(NGINX_VER) - 1; } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) { p = (u_char *) NGINX_VER_BUILD; n = sizeof(NGINX_VER_BUILD) - 1; } else { p = (u_char *) "nginx"; n = sizeof("nginx") - 1; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"server: %*s\"", n, p); b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_SERVER, p, n); } if (r->headers_out.date == NULL) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"date: %V\"", &ngx_cached_http_time); b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_DATE, ngx_cached_http_time.data, ngx_cached_http_time.len); } if (r->headers_out.content_type.len) { if (r->headers_out.content_type_len == r->headers_out.content_type.len && r->headers_out.charset.len) { n = r->headers_out.content_type.len + sizeof("; charset=") - 1 + r->headers_out.charset.len; p = ngx_pnalloc(r->pool, n); if (p == NULL) { return NGX_ERROR; } p = ngx_cpymem(p, r->headers_out.content_type.data, r->headers_out.content_type.len); p = ngx_cpymem(p, "; charset=", sizeof("; charset=") - 1); p = ngx_cpymem(p, r->headers_out.charset.data, r->headers_out.charset.len); /* updated r->headers_out.content_type is also needed for logging */ r->headers_out.content_type.len = n; r->headers_out.content_type.data = p - n; } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"content-type: %V\"", &r->headers_out.content_type); b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN, r->headers_out.content_type.data, r->headers_out.content_type.len); } if (r->headers_out.content_length == NULL && r->headers_out.content_length_n >= 0) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"content-length: %O\"", r->headers_out.content_length_n); if (r->headers_out.content_length_n > 0) { p = ngx_sprintf(b->last, "%O", r->headers_out.content_length_n); n = p - b->last; b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO, NULL, n); b->last = ngx_sprintf(b->last, "%O", r->headers_out.content_length_n); } else { b->last = (u_char *) ngx_http_v3_encode_field_ri(b->last, 0, NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO); } } if (r->headers_out.last_modified == NULL && r->headers_out.last_modified_time != -1) { n = sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1; p = ngx_pnalloc(r->pool, n); if (p == NULL) { return NGX_ERROR; } ngx_http_time(p, r->headers_out.last_modified_time); ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"last-modified: %*s\"", n, p); b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_LAST_MODIFIED, p, n); } if (r->headers_out.location && r->headers_out.location->value.len) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"location: %V\"", &r->headers_out.location->value); b->last = (u_char *) ngx_http_v3_encode_field_lri(b->last, 0, NGX_HTTP_V3_HEADER_LOCATION, r->headers_out.location->value.data, r->headers_out.location->value.len); } #if (NGX_HTTP_GZIP) if (r->gzip_vary) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"vary: Accept-Encoding\""); b->last = (u_char *) ngx_http_v3_encode_field_ri(b->last, 0, NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING); } #endif part = &r->headers_out.headers.part; header = part->elts; for (i = 0; /* void */; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (header[i].hash == 0) { continue; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 output header: \"%V: %V\"", &header[i].key, &header[i].value); b->last = (u_char *) ngx_http_v3_encode_field_l(b->last, &header[i].key, &header[i].value); } if (r->header_only) { b->last_buf = 1; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; cl->next = NULL; n = b->last - b->pos; h3c->payload_bytes += n; len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_HEADERS) + ngx_http_v3_encode_varlen_int(NULL, n); b = ngx_create_temp_buf(r->pool, len); if (b == NULL) { return NGX_ERROR; } b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, NGX_HTTP_V3_FRAME_HEADERS); b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n); hl = ngx_alloc_chain_link(r->pool); if (hl == NULL) { return NGX_ERROR; } hl->buf = b; hl->next = cl; *ll = hl; ll = &cl->next; if (r->headers_out.content_length_n >= 0 && !r->header_only && !r->expect_trailers) { len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_DATA) + ngx_http_v3_encode_varlen_int(NULL, r->headers_out.content_length_n); b = ngx_create_temp_buf(r->pool, len); if (b == NULL) { return NGX_ERROR; } b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, NGX_HTTP_V3_FRAME_DATA); b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, r->headers_out.content_length_n); h3c->payload_bytes += r->headers_out.content_length_n; h3c->total_bytes += r->headers_out.content_length_n; cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; cl->next = NULL; *ll = cl; } else { ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_v3_filter_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ngx_http_set_ctx(r, ctx, ngx_http_v3_filter_module); } for (cl = out; cl; cl = cl->next) { h3c->total_bytes += cl->buf->last - cl->buf->pos; } return ngx_http_write_filter(r, out); } static ngx_int_t ngx_http_v3_body_filter(ngx_http_request_t *r, ngx_chain_t *in) { u_char *chunk; off_t size; ngx_int_t rc; ngx_buf_t *b; ngx_chain_t *out, *cl, *tl, **ll; ngx_http_v3_session_t *h3c; ngx_http_v3_filter_ctx_t *ctx; if (in == NULL) { return ngx_http_next_body_filter(r, in); } ctx = ngx_http_get_module_ctx(r, ngx_http_v3_filter_module); if (ctx == NULL) { return ngx_http_next_body_filter(r, in); } h3c = ngx_http_v3_get_session(r->connection); out = NULL; ll = &out; size = 0; cl = in; for ( ;; ) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http3 chunk: %O", ngx_buf_size(cl->buf)); size += ngx_buf_size(cl->buf); if (cl->buf->flush || cl->buf->sync || ngx_buf_in_memory(cl->buf) || cl->buf->in_file) { tl = ngx_alloc_chain_link(r->pool); if (tl == NULL) { return NGX_ERROR; } tl->buf = cl->buf; *ll = tl; ll = &tl->next; } if (cl->next == NULL) { break; } cl = cl->next; } if (size) { tl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (tl == NULL) { return NGX_ERROR; } b = tl->buf; chunk = b->start; if (chunk == NULL) { chunk = ngx_palloc(r->pool, NGX_HTTP_V3_VARLEN_INT_LEN * 2); if (chunk == NULL) { return NGX_ERROR; } b->start = chunk; b->end = chunk + NGX_HTTP_V3_VARLEN_INT_LEN * 2; } b->tag = (ngx_buf_tag_t) &ngx_http_v3_filter_module; b->memory = 0; b->temporary = 1; b->pos = chunk; b->last = (u_char *) ngx_http_v3_encode_varlen_int(chunk, NGX_HTTP_V3_FRAME_DATA); b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, size); tl->next = out; out = tl; h3c->payload_bytes += size; } if (cl->buf->last_buf) { tl = ngx_http_v3_create_trailers(r, ctx); if (tl == NULL) { return NGX_ERROR; } cl->buf->last_buf = 0; *ll = tl; } else { *ll = NULL; } for (cl = out; cl; cl = cl->next) { h3c->total_bytes += cl->buf->last - cl->buf->pos; } rc = ngx_http_next_body_filter(r, out); ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out, (ngx_buf_tag_t) &ngx_http_v3_filter_module); return rc; } static ngx_chain_t * ngx_http_v3_create_trailers(ngx_http_request_t *r, ngx_http_v3_filter_ctx_t *ctx) { size_t len, n; u_char *p; ngx_buf_t *b; ngx_uint_t i; ngx_chain_t *cl, *hl; ngx_list_part_t *part; ngx_table_elt_t *header; ngx_http_v3_session_t *h3c; h3c = ngx_http_v3_get_session(r->connection); len = 0; part = &r->headers_out.trailers.part; header = part->elts; for (i = 0; /* void */; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (header[i].hash == 0) { continue; } len += ngx_http_v3_encode_field_l(NULL, &header[i].key, &header[i].value); } cl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (cl == NULL) { return NULL; } b = cl->buf; b->tag = (ngx_buf_tag_t) &ngx_http_v3_filter_module; b->memory = 0; b->last_buf = 1; if (len == 0) { b->temporary = 0; b->pos = b->last = NULL; return cl; } b->temporary = 1; len += ngx_http_v3_encode_field_section_prefix(NULL, 0, 0, 0); b->pos = ngx_palloc(r->pool, len); if (b->pos == NULL) { return NULL; } b->last = (u_char *) ngx_http_v3_encode_field_section_prefix(b->pos, 0, 0, 0); part = &r->headers_out.trailers.part; header = part->elts; for (i = 0; /* void */; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (header[i].hash == 0) { continue; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http3 output trailer: \"%V: %V\"", &header[i].key, &header[i].value); b->last = (u_char *) ngx_http_v3_encode_field_l(b->last, &header[i].key, &header[i].value); } n = b->last - b->pos; h3c->payload_bytes += n; hl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (hl == NULL) { return NULL; } b = hl->buf; p = b->start; if (p == NULL) { p = ngx_palloc(r->pool, NGX_HTTP_V3_VARLEN_INT_LEN * 2); if (p == NULL) { return NULL; } b->start = p; b->end = p + NGX_HTTP_V3_VARLEN_INT_LEN * 2; } b->tag = (ngx_buf_tag_t) &ngx_http_v3_filter_module; b->memory = 0; b->temporary = 1; b->pos = p; b->last = (u_char *) ngx_http_v3_encode_varlen_int(p, NGX_HTTP_V3_FRAME_HEADERS); b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n); hl->next = cl; return hl; } static ngx_int_t ngx_http_v3_filter_init(ngx_conf_t *cf) { ngx_http_next_header_filter = ngx_http_top_header_filter; ngx_http_top_header_filter = ngx_http_v3_header_filter; ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_v3_body_filter; return NGX_OK; }