Mercurial > hg > nginx-quic
view src/http/v2/ngx_http_v2_table.c @ 8531:41f4bd4c51f1
Disabled control characters and space in header names.
Control characters (0x00-0x1f, 0x7f), space, and colon were never allowed in
header names. The only somewhat valid use is header continuation which nginx
never supported and which is explicitly obsolete by RFC 7230.
Previously, such headers were considered invalid and were ignored by default
(as per ignore_invalid_headers directive). With this change, such headers
are unconditionally rejected.
It is expected to make nginx more resilient to various attacks, in particular,
with ignore_invalid_headers switched off (which is inherently unsecure, though
nevertheless sometimes used in the wild).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 28 Jun 2021 18:01:18 +0300 |
parents | 87e9e4aabf1b |
children |
line wrap: on
line source
/* * Copyright (C) Nginx, Inc. * Copyright (C) Valentin V. Bartenev */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define NGX_HTTP_V2_TABLE_SIZE 4096 static ngx_int_t ngx_http_v2_table_account(ngx_http_v2_connection_t *h2c, size_t size); static ngx_http_v2_header_t ngx_http_v2_static_table[] = { { ngx_string(":authority"), ngx_string("") }, { ngx_string(":method"), ngx_string("GET") }, { ngx_string(":method"), ngx_string("POST") }, { ngx_string(":path"), ngx_string("/") }, { ngx_string(":path"), ngx_string("/index.html") }, { ngx_string(":scheme"), ngx_string("http") }, { ngx_string(":scheme"), ngx_string("https") }, { ngx_string(":status"), ngx_string("200") }, { ngx_string(":status"), ngx_string("204") }, { ngx_string(":status"), ngx_string("206") }, { ngx_string(":status"), ngx_string("304") }, { ngx_string(":status"), ngx_string("400") }, { ngx_string(":status"), ngx_string("404") }, { ngx_string(":status"), ngx_string("500") }, { ngx_string("accept-charset"), ngx_string("") }, { ngx_string("accept-encoding"), ngx_string("gzip, deflate") }, { ngx_string("accept-language"), ngx_string("") }, { ngx_string("accept-ranges"), ngx_string("") }, { ngx_string("accept"), ngx_string("") }, { ngx_string("access-control-allow-origin"), ngx_string("") }, { ngx_string("age"), ngx_string("") }, { ngx_string("allow"), ngx_string("") }, { ngx_string("authorization"), ngx_string("") }, { ngx_string("cache-control"), ngx_string("") }, { ngx_string("content-disposition"), ngx_string("") }, { ngx_string("content-encoding"), ngx_string("") }, { ngx_string("content-language"), ngx_string("") }, { ngx_string("content-length"), ngx_string("") }, { ngx_string("content-location"), ngx_string("") }, { ngx_string("content-range"), ngx_string("") }, { ngx_string("content-type"), ngx_string("") }, { ngx_string("cookie"), ngx_string("") }, { ngx_string("date"), ngx_string("") }, { ngx_string("etag"), ngx_string("") }, { ngx_string("expect"), ngx_string("") }, { ngx_string("expires"), ngx_string("") }, { ngx_string("from"), ngx_string("") }, { ngx_string("host"), ngx_string("") }, { ngx_string("if-match"), ngx_string("") }, { ngx_string("if-modified-since"), ngx_string("") }, { ngx_string("if-none-match"), ngx_string("") }, { ngx_string("if-range"), ngx_string("") }, { ngx_string("if-unmodified-since"), ngx_string("") }, { ngx_string("last-modified"), ngx_string("") }, { ngx_string("link"), ngx_string("") }, { ngx_string("location"), ngx_string("") }, { ngx_string("max-forwards"), ngx_string("") }, { ngx_string("proxy-authenticate"), ngx_string("") }, { ngx_string("proxy-authorization"), ngx_string("") }, { ngx_string("range"), ngx_string("") }, { ngx_string("referer"), ngx_string("") }, { ngx_string("refresh"), ngx_string("") }, { ngx_string("retry-after"), ngx_string("") }, { ngx_string("server"), ngx_string("") }, { ngx_string("set-cookie"), ngx_string("") }, { ngx_string("strict-transport-security"), ngx_string("") }, { ngx_string("transfer-encoding"), ngx_string("") }, { ngx_string("user-agent"), ngx_string("") }, { ngx_string("vary"), ngx_string("") }, { ngx_string("via"), ngx_string("") }, { ngx_string("www-authenticate"), ngx_string("") }, }; #define NGX_HTTP_V2_STATIC_TABLE_ENTRIES \ (sizeof(ngx_http_v2_static_table) \ / sizeof(ngx_http_v2_header_t)) ngx_str_t * ngx_http_v2_get_static_name(ngx_uint_t index) { return &ngx_http_v2_static_table[index - 1].name; } ngx_str_t * ngx_http_v2_get_static_value(ngx_uint_t index) { return &ngx_http_v2_static_table[index - 1].value; } ngx_int_t ngx_http_v2_get_indexed_header(ngx_http_v2_connection_t *h2c, ngx_uint_t index, ngx_uint_t name_only) { u_char *p; size_t rest; ngx_http_v2_header_t *entry; if (index == 0) { ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0, "client sent invalid hpack table index 0"); return NGX_ERROR; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0, "http2 get indexed %s: %ui", name_only ? "name" : "header", index); index--; if (index < NGX_HTTP_V2_STATIC_TABLE_ENTRIES) { h2c->state.header = ngx_http_v2_static_table[index]; return NGX_OK; } index -= NGX_HTTP_V2_STATIC_TABLE_ENTRIES; if (index < h2c->hpack.added - h2c->hpack.deleted) { index = (h2c->hpack.added - index - 1) % h2c->hpack.allocated; entry = h2c->hpack.entries[index]; p = ngx_pnalloc(h2c->state.pool, entry->name.len + 1); if (p == NULL) { return NGX_ERROR; } h2c->state.header.name.len = entry->name.len; h2c->state.header.name.data = p; rest = h2c->hpack.storage + NGX_HTTP_V2_TABLE_SIZE - entry->name.data; if (entry->name.len > rest) { p = ngx_cpymem(p, entry->name.data, rest); p = ngx_cpymem(p, h2c->hpack.storage, entry->name.len - rest); } else { p = ngx_cpymem(p, entry->name.data, entry->name.len); } *p = '\0'; if (name_only) { return NGX_OK; } p = ngx_pnalloc(h2c->state.pool, entry->value.len + 1); if (p == NULL) { return NGX_ERROR; } h2c->state.header.value.len = entry->value.len; h2c->state.header.value.data = p; rest = h2c->hpack.storage + NGX_HTTP_V2_TABLE_SIZE - entry->value.data; if (entry->value.len > rest) { p = ngx_cpymem(p, entry->value.data, rest); p = ngx_cpymem(p, h2c->hpack.storage, entry->value.len - rest); } else { p = ngx_cpymem(p, entry->value.data, entry->value.len); } *p = '\0'; return NGX_OK; } ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0, "client sent out of bound hpack table index: %ui", index); return NGX_ERROR; } ngx_int_t ngx_http_v2_add_header(ngx_http_v2_connection_t *h2c, ngx_http_v2_header_t *header) { size_t avail; ngx_uint_t index; ngx_http_v2_header_t *entry, **entries; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0, "http2 table add: \"%V: %V\"", &header->name, &header->value); if (h2c->hpack.entries == NULL) { h2c->hpack.allocated = 64; h2c->hpack.size = NGX_HTTP_V2_TABLE_SIZE; h2c->hpack.free = NGX_HTTP_V2_TABLE_SIZE; h2c->hpack.entries = ngx_palloc(h2c->connection->pool, sizeof(ngx_http_v2_header_t *) * h2c->hpack.allocated); if (h2c->hpack.entries == NULL) { return NGX_ERROR; } h2c->hpack.storage = ngx_palloc(h2c->connection->pool, h2c->hpack.free); if (h2c->hpack.storage == NULL) { return NGX_ERROR; } h2c->hpack.pos = h2c->hpack.storage; } if (ngx_http_v2_table_account(h2c, header->name.len + header->value.len) != NGX_OK) { return NGX_OK; } if (h2c->hpack.reused == h2c->hpack.deleted) { entry = ngx_palloc(h2c->connection->pool, sizeof(ngx_http_v2_header_t)); if (entry == NULL) { return NGX_ERROR; } } else { entry = h2c->hpack.entries[h2c->hpack.reused++ % h2c->hpack.allocated]; } avail = h2c->hpack.storage + NGX_HTTP_V2_TABLE_SIZE - h2c->hpack.pos; entry->name.len = header->name.len; entry->name.data = h2c->hpack.pos; if (avail >= header->name.len) { h2c->hpack.pos = ngx_cpymem(h2c->hpack.pos, header->name.data, header->name.len); } else { ngx_memcpy(h2c->hpack.pos, header->name.data, avail); h2c->hpack.pos = ngx_cpymem(h2c->hpack.storage, header->name.data + avail, header->name.len - avail); avail = NGX_HTTP_V2_TABLE_SIZE; } avail -= header->name.len; entry->value.len = header->value.len; entry->value.data = h2c->hpack.pos; if (avail >= header->value.len) { h2c->hpack.pos = ngx_cpymem(h2c->hpack.pos, header->value.data, header->value.len); } else { ngx_memcpy(h2c->hpack.pos, header->value.data, avail); h2c->hpack.pos = ngx_cpymem(h2c->hpack.storage, header->value.data + avail, header->value.len - avail); } if (h2c->hpack.allocated == h2c->hpack.added - h2c->hpack.deleted) { entries = ngx_palloc(h2c->connection->pool, sizeof(ngx_http_v2_header_t *) * (h2c->hpack.allocated + 64)); if (entries == NULL) { return NGX_ERROR; } index = h2c->hpack.deleted % h2c->hpack.allocated; ngx_memcpy(entries, &h2c->hpack.entries[index], (h2c->hpack.allocated - index) * sizeof(ngx_http_v2_header_t *)); ngx_memcpy(&entries[h2c->hpack.allocated - index], h2c->hpack.entries, index * sizeof(ngx_http_v2_header_t *)); (void) ngx_pfree(h2c->connection->pool, h2c->hpack.entries); h2c->hpack.entries = entries; h2c->hpack.added = h2c->hpack.allocated; h2c->hpack.deleted = 0; h2c->hpack.reused = 0; h2c->hpack.allocated += 64; } h2c->hpack.entries[h2c->hpack.added++ % h2c->hpack.allocated] = entry; return NGX_OK; } static ngx_int_t ngx_http_v2_table_account(ngx_http_v2_connection_t *h2c, size_t size) { ngx_http_v2_header_t *entry; size += 32; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0, "http2 table account: %uz free:%uz", size, h2c->hpack.free); if (size <= h2c->hpack.free) { h2c->hpack.free -= size; return NGX_OK; } if (size > h2c->hpack.size) { h2c->hpack.deleted = h2c->hpack.added; h2c->hpack.free = h2c->hpack.size; return NGX_DECLINED; } do { entry = h2c->hpack.entries[h2c->hpack.deleted++ % h2c->hpack.allocated]; h2c->hpack.free += 32 + entry->name.len + entry->value.len; } while (size > h2c->hpack.free); h2c->hpack.free -= size; return NGX_OK; } ngx_int_t ngx_http_v2_table_size(ngx_http_v2_connection_t *h2c, size_t size) { ssize_t needed; ngx_http_v2_header_t *entry; if (size > NGX_HTTP_V2_TABLE_SIZE) { ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0, "client sent invalid table size update: %uz", size); return NGX_ERROR; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0, "http2 new hpack table size: %uz was:%uz", size, h2c->hpack.size); needed = h2c->hpack.size - size; while (needed > (ssize_t) h2c->hpack.free) { entry = h2c->hpack.entries[h2c->hpack.deleted++ % h2c->hpack.allocated]; h2c->hpack.free += 32 + entry->name.len + entry->value.len; } h2c->hpack.size = size; h2c->hpack.free -= needed; return NGX_OK; }