Index: CHANGES =================================================================== --- CHANGES (revision 894148) +++ CHANGES (working copy) @@ -8,6 +8,11 @@ control is still vulnerable, unless using OpenSSL >= 0.9.8l. [Joe Orton, Ruediger Pluem] + *) Allow fine control over the removal of Last-Modified and ETag headers + within the INCLUDES filter, making it possible to cache responses if + desired. Fix the default value of the SSIAccessEnable directive. + [Graham Leggett] + *) mod_filter: fix FilterProvider matching where "dispatch" string doesn't exist. PR 48054 [] Index: modules/filters/mod_include.c =================================================================== --- modules/filters/mod_include.c (revision 894148) +++ modules/filters/mod_include.c (working copy) @@ -115,7 +115,9 @@ const char *default_time_fmt; const char *undefined_echo; xbithack_t xbithack; - const int accessenable; + int accessenable; + int lastmodified; + int etag; } include_dir_config; typedef struct { @@ -461,6 +463,9 @@ #define DEFAULT_ERROR_MSG "[an error occurred while processing this directive]" #define DEFAULT_TIME_FORMAT "%A, %d-%b-%Y %H:%M:%S %Z" #define DEFAULT_UNDEFINED_ECHO "(none)" +#define DEFAULT_ACCESSENABLE 0 +#define DEFAULT_LASTMODIFIED 0 +#define DEFAULT_ETAG 0 #ifdef XBITHACK #define DEFAULT_XBITHACK XBITHACK_FULL @@ -3529,7 +3534,9 @@ * We don't know if we are going to be including a file or executing * a program - in either case a strong ETag header will likely be invalid. */ - apr_table_setn(f->r->notes, "no-etag", ""); + if (!conf->etag) { + apr_table_setn(f->r->notes, "no-etag", ""); + } return OK; } @@ -3618,13 +3625,32 @@ * a program which may change the Last-Modified header or make the * content completely dynamic. Therefore, we can't support these * headers. - * Exception: XBitHack full means we *should* set the Last-Modified field. + * + * Exception: XBitHack full means we *should* set the + * Last-Modified field. + * + * SSILastModified on means we *should* set the Last-Modified field + * if not present, or respect an existing value if present. */ + /* Must we respect the last modified header? By default, no */ + if (conf->lastmodified) { + + /* update the last modified if we have a valid time, and only if + * we don't already have a valid last modified. + */ + if (r->finfo.valid & APR_FINFO_MTIME + && !apr_table_get(f->r->headers_out, "Last-Modified")) { + ap_update_mtime(r, r->finfo.mtime); + ap_set_last_modified(r); + } + + } + /* Assure the platform supports Group protections */ - if ((conf->xbithack == XBITHACK_FULL) + else if (((conf->xbithack == XBITHACK_FULL) && (r->finfo.valid & APR_FINFO_GPROT) - && (r->finfo.protection & APR_GEXECUTE)) { + && (r->finfo.protection & APR_GEXECUTE))) { ap_update_mtime(r, r->finfo.mtime); ap_set_last_modified(r); } @@ -3704,6 +3730,9 @@ result->default_time_fmt = DEFAULT_TIME_FORMAT; result->undefined_echo = DEFAULT_UNDEFINED_ECHO; result->xbithack = DEFAULT_XBITHACK; + result->accessenable = DEFAULT_ACCESSENABLE; + result->lastmodified = DEFAULT_LASTMODIFIED; + result->etag = DEFAULT_ETAG; return result; } @@ -3856,6 +3885,14 @@ AP_INIT_FLAG("SSIAccessEnable", ap_set_flag_slot, (void *)APR_OFFSETOF(include_dir_config, accessenable), OR_LIMIT, "Whether testing access is enabled. Limited to 'on' or 'off'"), + AP_INIT_FLAG("SSILastModified", ap_set_flag_slot, + (void *)APR_OFFSETOF(include_dir_config, lastmodified), + OR_LIMIT, "Whether to set the last modified header or respect " + "an existing header. Limited to 'on' or 'off'"), + AP_INIT_FLAG("SSIEtag", ap_set_flag_slot, + (void *)APR_OFFSETOF(include_dir_config, etag), + OR_LIMIT, "Whether to allow the generation of ETags within the server. " + "Existing ETags will be preserved. Limited to 'on' or 'off'"), {NULL} }; Index: docs/manual/mod/mod_include.xml =================================================================== --- docs/manual/mod/mod_include.xml (revision 894148) +++ docs/manual/mod/mod_include.xml (working copy) @@ -801,6 +801,84 @@ +SSIETag +Controls whether ETags are generated by the server. +SSIETag on|off +SSIETag off +directory.htaccess + + +

Under normal circumstances, a file filtered by mod_include + may contain elements that are either dynamically generated, or that may + have changed independently of the original file. As a result, by default + the server is asked not to generate an ETag header for the + response by adding no-etag to the request notes.

+ +

The SSIETag directive suppresses this + behaviour, and allows the server to generate an ETag header. + This can be used to enable caching of the output. Note that a backend server + or dynamic content generator may generate an ETag of its own, ignoring + no-etag, and this ETag will be passed by + mod_include regardless of the value of this setting. + SSIETag can take on the following values:

+ +
+ +
off
+
no-etag will be added to the request notes, and the server + is asked not to generate an ETag. Where a server ignores the value of + no-etag and generates an ETag anyway, the ETag will be + respected.
+ +
on
+
Existing ETags will be respected, and ETags generated by the server will + be passed on in the response.
+ +
+ + + + + +SSILastModified +Controls whether Last-Modified headers are generated by the +server. +SSILastModified on|off +SSILastModified off +directory.htaccess + + +

Under normal circumstances, a file filtered by mod_include + may contain elements that are either dynamically generated, or that may + have changed independently of the original file. As a result, by default + the Last-Modified header is stripped from the response.

+ +

The SSILastModified directive overrides this + behaviour, and allows the Last-Modified header to be respected + if already present, or set if the header is not already present. This can + be used to enable caching of the output. SSILastModified + can take on the following values:

+ +
+ +
off
+
The Last-Modified header will be stripped from responses, + unless the XBitHack directive + is set to full as described below.
+ +
on
+
The Last-Modified header will be respected if already + present in a response, and added to the response if the response is a + file and the header is missing. The + SSILastModified directive + takes precedence over XBitHack.
+ +
+ + + + + XBitHack Parse SSI directives in files with the execute bit set @@ -837,7 +915,14 @@ group-execute bit is unset for every SSI script which might #include a CGI or otherwise produces different output on each hit (or could potentially change on subsequent requests).

+ +

The SSILastModified + directive takes precedence over the + XBitHack directive when + SSILastModified is set to + on.

+