lighttpd 1.4.x https://www.lighttpd.net/
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#include "first.h"
#include "array.h"
#include "buffer.h"
#include "log.h"
#include "request.h"
#include "response.h"
#include "stat_cache.h"
#include "plugin.h"
#include <sys/types.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_PWD_H
# include <pwd.h>
#endif
typedef struct {
const array *exclude_user;
const array *include_user;
const buffer *path;
const buffer *basepath;
unsigned short letterhomes;
unsigned short active;
} plugin_config;
typedef struct {
PLUGIN_DATA;
plugin_config defaults;
plugin_config conf;
[multiple] Y2038 32-bit signed time_t mitigations Most OS platforms have already provided solutions to Y2038 32-bit signed time_t 5 - 10 years ago (or more!) Notable exceptions are Linux i686 and FreeBSD i386. Since 32-bit systems tend to be embedded systems, and since many distros take years to pick up new software, this commit aims to provide Y2038 mitigations for lighttpd running on 32-bit systems with Y2038-unsafe 32-bit signed time_t * Y2038: lighttpd 1.4.60 and later report Y2038 safety $ lighttpd -V + Y2038 support # Y2038-SAFE $ lighttpd -V - Y2038 support (unsafe 32-bit signed time_t) # Y2038-UNSAFE * Y2038: general platform info * Y2038-SAFE: lighttpd 64-bit builds on platforms using 64-bit time_t - all major 64-bit platforms (known to this author) use 64-bit time_t * Y2038-SAFE: lighttpd 32-bit builds on platforms using 64-bit time_t - Linux x32 ABI (different from i686) - FreeBSD all 32-bit and 64-bit architectures *except* 32-bit i386 - NetBSD 6.0 (released Oct 2012) all 32-bit and 64-bit architectures - OpenBSD 5.5 (released May 2014) all 32-bit and 64-bit architectures - Microsoft Windows XP and Visual Studio 2005 (? unsure ?) Another reference suggests Visual Studio 2015 defaults to 64-bit time_t - MacOS 10.15 Catalina (released 2019) drops support for 32-bit apps * Y2038-SAFE: lighttpd 32-bit builds on platforms using 32-bit unsigned time_t - e.g. OpenVMS (unknown if lighttpd builds on this platform) * Y2038-UNSAFE: lighttpd 32-bit builds on platforms using 32-bit signed time_t - Linux 32-bit (including i686) - glibc 32-bit library support not yet available for 64-bit time_t - https://sourceware.org/glibc/wiki/Y2038ProofnessDesign - Linux kernel 5.6 on 32-bit platforms does support 64-bit time_t https://itsubuntu.com/linux-kernel-5-6-to-fix-the-year-2038-issue-unix-y2k/ - https://www.gnu.org/software/libc/manual/html_node/64_002dbit-time-symbol-handling.html "Note: at this point, 64-bit time support in dual-time configurations is work-in-progress, so for these configurations, the public API only makes the 32-bit time support available. In a later change, the public API will allow user code to choose the time size for a given compilation unit." - compiling with -D_TIME_BITS=64 currently has no effect - glibc recent (Jul 2021) mailing list discussion - https://public-inbox.org/bug-gnulib/878s2ozq70.fsf@oldenburg.str.redhat.com/T/ - FreeBSD i386 - DragonFlyBSD 32-bit * Y2038 mitigations attempted on Y2038-UNSAFE platforms (32-bit signed time_t) * lighttpd prefers system monotonic clock instead of realtime clock in places where realtime clock is not required * lighttpd treats negative time_t values as after 19 Jan 2038 03:14:07 GMT * (lighttpd presumes that lighttpd will not encounter dates before 1970 during normal operation.) * lighttpd casts struct stat st.st_mtime (and st.st_*time) through uint64_t to convert negative timestamps for comparisions with 64-bit timestamps (treating negative timestamp values as after 19 Jan 2038 03:14:07 GMT) * lighttpd provides unix_time64_t (int64_t) and * lighttpd provides struct unix_timespec64 (unix_timespec64_t) (struct timespec equivalent using unix_time64_t tv_sec member) * lighttpd provides gmtime64_r() and localtime64_r() wrappers for platforms 32-bit platforms using 32-bit time_t and lighttpd temporarily shifts the year in order to use gmtime_r() and localtime_r() (or gmtime() and localtime()) from standard libraries, before readjusting year and passing struct tm to formatting functions such as strftime() * lighttpd provides TIME64_CAST() macro to cast signed 32-bit time_t to unsigned 32-bit and then to unix_time64_t * Note: while lighttpd tries handle times past 19 Jan 2038 03:14:07 GMT on 32-bit platforms using 32-bit signed time_t, underlying libraries and underlying filesystems might not behave properly after 32-bit signed time_t overflows (19 Jan 2038 03:14:08 GMT). If a given 32-bit OS does not work properly using negative time_t values, then lighttpd likely will not work properly on that system. * Other references and blogs - https://en.wikipedia.org/wiki/Year_2038_problem - https://en.wikipedia.org/wiki/Time_formatting_and_storage_bugs - http://www.lieberbiber.de/2017/03/14/a-look-at-the-year-20362038-problems-and-time-proofness-in-various-systems/
12 months ago
unix_time64_t cache_ts[2];
buffer cache_user[2];
buffer cache_path[2];
} plugin_data;
INIT_FUNC(mod_userdir_init) {
return calloc(1, sizeof(plugin_data));
}
FREE_FUNC(mod_userdir_free) {
plugin_data * const p = p_d;
free(p->cache_user[0].ptr);
free(p->cache_user[1].ptr);
free(p->cache_path[0].ptr);
free(p->cache_path[1].ptr);
}
static void mod_userdir_merge_config_cpv(plugin_config * const pconf, const config_plugin_value_t * const cpv) {
switch (cpv->k_id) { /* index into static config_plugin_keys_t cpk[] */
case 0: /* userdir.path */
pconf->path = cpv->v.b;
break;
case 1: /* userdir.exclude-user */
pconf->exclude_user = cpv->v.a;
break;
case 2: /* userdir.include-user */
pconf->include_user = cpv->v.a;
break;
case 3: /* userdir.basepath */
pconf->basepath = cpv->v.b;
break;
case 4: /* userdir.letterhomes */
pconf->letterhomes = cpv->v.u;
break;
case 5: /* userdir.active */
pconf->active = cpv->v.u;
break;
default:/* should not happen */
return;
}
}
static void mod_userdir_merge_config(plugin_config * const pconf, const config_plugin_value_t *cpv) {
do {
mod_userdir_merge_config_cpv(pconf, cpv);
} while ((++cpv)->k_id != -1);
}
static void mod_userdir_patch_config(request_st * const r, plugin_data * const p) {
memcpy(&p->conf, &p->defaults, sizeof(plugin_config));
for (int i = 1, used = p->nconfig; i < used; ++i) {
if (config_check_cond(r, (uint32_t)p->cvlist[i].k_id))
mod_userdir_merge_config(&p->conf, p->cvlist + p->cvlist[i].v.u2[0]);
}
}
SETDEFAULTS_FUNC(mod_userdir_set_defaults) {
static const config_plugin_keys_t cpk[] = {
{ CONST_STR_LEN("userdir.path"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("userdir.exclude-user"),
T_CONFIG_ARRAY_VLIST,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("userdir.include-user"),
T_CONFIG_ARRAY_VLIST,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("userdir.basepath"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("userdir.letterhomes"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("userdir.active"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ NULL, 0,
T_CONFIG_UNSET,
T_CONFIG_SCOPE_UNSET }
};
plugin_data * const p = p_d;
if (!config_plugin_values_init(srv, p, cpk, "mod_userdir"))
return HANDLER_ERROR;
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
/* process and validate config directives
* (init i to 0 if global context; to 1 to skip empty global context) */
for (int i = !p->cvlist[0].v.u2[1]; i < p->nconfig; ++i) {
config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0];
for (; -1 != cpv->k_id; ++cpv) {
switch (cpv->k_id) {
case 0: /* userdir.path */
case 1: /* userdir.exclude-user */
case 2: /* userdir.include-user */
break;
case 3: /* userdir.basepath */
if (buffer_is_blank(cpv->v.b))
cpv->v.b = NULL;
break;
case 4: /* userdir.letterhomes */
case 5: /* userdir.active */
break;
default:/* should not happen */
break;
}
}
}
/* enabled by default for backward compatibility;
* if userdir.path isn't set userdir is disabled too,
* but you can't disable it by setting it to an empty string. */
p->defaults.active = 1;
/* initialize p->defaults from global config context */
if (p->nconfig > 0 && p->cvlist->v.u2[1]) {
const config_plugin_value_t *cpv = p->cvlist + p->cvlist->v.u2[0];
if (-1 != cpv->k_id)
mod_userdir_merge_config(&p->defaults, cpv);
}
return HANDLER_GO_ON;
}
static int mod_userdir_in_vlist_nc(const array * const a, const char * const k, const size_t klen) {
for (uint32_t i = 0, used = a->used; i < used; ++i) {
const data_string * const ds = (const data_string *)a->data[i];
if (buffer_eq_icase_slen(&ds->value, k, klen)) return 1;
}
return 0;
}
static int mod_userdir_in_vlist(const array * const a, const char * const k, const size_t klen) {
for (uint32_t i = 0, used = a->used; i < used; ++i) {
const data_string * const ds = (const data_string *)a->data[i];
if (buffer_eq_slen(&ds->value, k, klen)) return 1;
}
return 0;
}
__attribute_noinline__
static handler_t mod_userdir_docroot_construct(request_st * const r, plugin_data * const p, const char * const uptr, const size_t ulen) {
char u[256];
if (ulen >= sizeof(u)) return HANDLER_GO_ON;
memcpy(u, uptr, ulen);
u[ulen] = '\0';
/* we build the physical path */
buffer * const b = r->tmp_buf;
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
if (!p->conf.basepath) {
#ifdef HAVE_PWD_H
/* getpwnam() lookup is expensive; first check 2-element cache */
[multiple] Y2038 32-bit signed time_t mitigations Most OS platforms have already provided solutions to Y2038 32-bit signed time_t 5 - 10 years ago (or more!) Notable exceptions are Linux i686 and FreeBSD i386. Since 32-bit systems tend to be embedded systems, and since many distros take years to pick up new software, this commit aims to provide Y2038 mitigations for lighttpd running on 32-bit systems with Y2038-unsafe 32-bit signed time_t * Y2038: lighttpd 1.4.60 and later report Y2038 safety $ lighttpd -V + Y2038 support # Y2038-SAFE $ lighttpd -V - Y2038 support (unsafe 32-bit signed time_t) # Y2038-UNSAFE * Y2038: general platform info * Y2038-SAFE: lighttpd 64-bit builds on platforms using 64-bit time_t - all major 64-bit platforms (known to this author) use 64-bit time_t * Y2038-SAFE: lighttpd 32-bit builds on platforms using 64-bit time_t - Linux x32 ABI (different from i686) - FreeBSD all 32-bit and 64-bit architectures *except* 32-bit i386 - NetBSD 6.0 (released Oct 2012) all 32-bit and 64-bit architectures - OpenBSD 5.5 (released May 2014) all 32-bit and 64-bit architectures - Microsoft Windows XP and Visual Studio 2005 (? unsure ?) Another reference suggests Visual Studio 2015 defaults to 64-bit time_t - MacOS 10.15 Catalina (released 2019) drops support for 32-bit apps * Y2038-SAFE: lighttpd 32-bit builds on platforms using 32-bit unsigned time_t - e.g. OpenVMS (unknown if lighttpd builds on this platform) * Y2038-UNSAFE: lighttpd 32-bit builds on platforms using 32-bit signed time_t - Linux 32-bit (including i686) - glibc 32-bit library support not yet available for 64-bit time_t - https://sourceware.org/glibc/wiki/Y2038ProofnessDesign - Linux kernel 5.6 on 32-bit platforms does support 64-bit time_t https://itsubuntu.com/linux-kernel-5-6-to-fix-the-year-2038-issue-unix-y2k/ - https://www.gnu.org/software/libc/manual/html_node/64_002dbit-time-symbol-handling.html "Note: at this point, 64-bit time support in dual-time configurations is work-in-progress, so for these configurations, the public API only makes the 32-bit time support available. In a later change, the public API will allow user code to choose the time size for a given compilation unit." - compiling with -D_TIME_BITS=64 currently has no effect - glibc recent (Jul 2021) mailing list discussion - https://public-inbox.org/bug-gnulib/878s2ozq70.fsf@oldenburg.str.redhat.com/T/ - FreeBSD i386 - DragonFlyBSD 32-bit * Y2038 mitigations attempted on Y2038-UNSAFE platforms (32-bit signed time_t) * lighttpd prefers system monotonic clock instead of realtime clock in places where realtime clock is not required * lighttpd treats negative time_t values as after 19 Jan 2038 03:14:07 GMT * (lighttpd presumes that lighttpd will not encounter dates before 1970 during normal operation.) * lighttpd casts struct stat st.st_mtime (and st.st_*time) through uint64_t to convert negative timestamps for comparisions with 64-bit timestamps (treating negative timestamp values as after 19 Jan 2038 03:14:07 GMT) * lighttpd provides unix_time64_t (int64_t) and * lighttpd provides struct unix_timespec64 (unix_timespec64_t) (struct timespec equivalent using unix_time64_t tv_sec member) * lighttpd provides gmtime64_r() and localtime64_r() wrappers for platforms 32-bit platforms using 32-bit time_t and lighttpd temporarily shifts the year in order to use gmtime_r() and localtime_r() (or gmtime() and localtime()) from standard libraries, before readjusting year and passing struct tm to formatting functions such as strftime() * lighttpd provides TIME64_CAST() macro to cast signed 32-bit time_t to unsigned 32-bit and then to unix_time64_t * Note: while lighttpd tries handle times past 19 Jan 2038 03:14:07 GMT on 32-bit platforms using 32-bit signed time_t, underlying libraries and underlying filesystems might not behave properly after 32-bit signed time_t overflows (19 Jan 2038 03:14:08 GMT). If a given 32-bit OS does not work properly using negative time_t values, then lighttpd likely will not work properly on that system. * Other references and blogs - https://en.wikipedia.org/wiki/Year_2038_problem - https://en.wikipedia.org/wiki/Time_formatting_and_storage_bugs - http://www.lieberbiber.de/2017/03/14/a-look-at-the-year-20362038-problems-and-time-proofness-in-various-systems/
12 months ago
const unix_time64_t cur_ts = log_monotonic_secs;
int cached = -1;
const int cache_sz =(int)(sizeof(p->cache_user)/sizeof(*p->cache_user));
for (int i = 0; i < cache_sz; ++i) {
if (cur_ts - p->cache_ts[i] < 60 && p->cache_user[i].used
&& buffer_eq_slen(&p->cache_user[i], u, ulen)) {
cached = i;
break;
}
}
struct passwd *pwd;
if (cached >= 0) {
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
buffer_copy_path_len2(b, BUF_PTR_LEN(&p->cache_path[cached]),
BUF_PTR_LEN(p->conf.path));
}
else if ((pwd = getpwnam(u))) {
const size_t plen = strlen(pwd->pw_dir);
buffer_copy_path_len2(b, pwd->pw_dir, plen,
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
BUF_PTR_LEN(p->conf.path));
if (!stat_cache_path_isdir(b)) {
return HANDLER_GO_ON;
}
/* update cache, replacing oldest entry */
cached = 0;
[multiple] Y2038 32-bit signed time_t mitigations Most OS platforms have already provided solutions to Y2038 32-bit signed time_t 5 - 10 years ago (or more!) Notable exceptions are Linux i686 and FreeBSD i386. Since 32-bit systems tend to be embedded systems, and since many distros take years to pick up new software, this commit aims to provide Y2038 mitigations for lighttpd running on 32-bit systems with Y2038-unsafe 32-bit signed time_t * Y2038: lighttpd 1.4.60 and later report Y2038 safety $ lighttpd -V + Y2038 support # Y2038-SAFE $ lighttpd -V - Y2038 support (unsafe 32-bit signed time_t) # Y2038-UNSAFE * Y2038: general platform info * Y2038-SAFE: lighttpd 64-bit builds on platforms using 64-bit time_t - all major 64-bit platforms (known to this author) use 64-bit time_t * Y2038-SAFE: lighttpd 32-bit builds on platforms using 64-bit time_t - Linux x32 ABI (different from i686) - FreeBSD all 32-bit and 64-bit architectures *except* 32-bit i386 - NetBSD 6.0 (released Oct 2012) all 32-bit and 64-bit architectures - OpenBSD 5.5 (released May 2014) all 32-bit and 64-bit architectures - Microsoft Windows XP and Visual Studio 2005 (? unsure ?) Another reference suggests Visual Studio 2015 defaults to 64-bit time_t - MacOS 10.15 Catalina (released 2019) drops support for 32-bit apps * Y2038-SAFE: lighttpd 32-bit builds on platforms using 32-bit unsigned time_t - e.g. OpenVMS (unknown if lighttpd builds on this platform) * Y2038-UNSAFE: lighttpd 32-bit builds on platforms using 32-bit signed time_t - Linux 32-bit (including i686) - glibc 32-bit library support not yet available for 64-bit time_t - https://sourceware.org/glibc/wiki/Y2038ProofnessDesign - Linux kernel 5.6 on 32-bit platforms does support 64-bit time_t https://itsubuntu.com/linux-kernel-5-6-to-fix-the-year-2038-issue-unix-y2k/ - https://www.gnu.org/software/libc/manual/html_node/64_002dbit-time-symbol-handling.html "Note: at this point, 64-bit time support in dual-time configurations is work-in-progress, so for these configurations, the public API only makes the 32-bit time support available. In a later change, the public API will allow user code to choose the time size for a given compilation unit." - compiling with -D_TIME_BITS=64 currently has no effect - glibc recent (Jul 2021) mailing list discussion - https://public-inbox.org/bug-gnulib/878s2ozq70.fsf@oldenburg.str.redhat.com/T/ - FreeBSD i386 - DragonFlyBSD 32-bit * Y2038 mitigations attempted on Y2038-UNSAFE platforms (32-bit signed time_t) * lighttpd prefers system monotonic clock instead of realtime clock in places where realtime clock is not required * lighttpd treats negative time_t values as after 19 Jan 2038 03:14:07 GMT * (lighttpd presumes that lighttpd will not encounter dates before 1970 during normal operation.) * lighttpd casts struct stat st.st_mtime (and st.st_*time) through uint64_t to convert negative timestamps for comparisions with 64-bit timestamps (treating negative timestamp values as after 19 Jan 2038 03:14:07 GMT) * lighttpd provides unix_time64_t (int64_t) and * lighttpd provides struct unix_timespec64 (unix_timespec64_t) (struct timespec equivalent using unix_time64_t tv_sec member) * lighttpd provides gmtime64_r() and localtime64_r() wrappers for platforms 32-bit platforms using 32-bit time_t and lighttpd temporarily shifts the year in order to use gmtime_r() and localtime_r() (or gmtime() and localtime()) from standard libraries, before readjusting year and passing struct tm to formatting functions such as strftime() * lighttpd provides TIME64_CAST() macro to cast signed 32-bit time_t to unsigned 32-bit and then to unix_time64_t * Note: while lighttpd tries handle times past 19 Jan 2038 03:14:07 GMT on 32-bit platforms using 32-bit signed time_t, underlying libraries and underlying filesystems might not behave properly after 32-bit signed time_t overflows (19 Jan 2038 03:14:08 GMT). If a given 32-bit OS does not work properly using negative time_t values, then lighttpd likely will not work properly on that system. * Other references and blogs - https://en.wikipedia.org/wiki/Year_2038_problem - https://en.wikipedia.org/wiki/Time_formatting_and_storage_bugs - http://www.lieberbiber.de/2017/03/14/a-look-at-the-year-20362038-problems-and-time-proofness-in-various-systems/
12 months ago
unix_time64_t cache_ts = p->cache_ts[0];
for (int i = 1; i < cache_sz; ++i) {
if (cache_ts > p->cache_ts[i]) {
cache_ts = p->cache_ts[i];
cached = i;
}
}
p->cache_ts[cached] = cur_ts;
buffer_copy_string_len(&p->cache_path[cached], b->ptr, plen);
buffer_copy_string_len(&p->cache_user[cached], u, ulen);
}
else /* user not found */
#endif
return HANDLER_GO_ON;
} else {
/* check if the username is valid
* a request for /~../ should lead to a directory traversal
* limiting to [-_a-z0-9.] should fix it */
if (ulen <= 2 && (u[0] == '.' && (1 == ulen || u[1] == '.'))) {
return HANDLER_GO_ON;
}
for (size_t i = 0; i < ulen; ++i) {
const int c = u[i];
if (!(light_isalnum(c) || c == '-' || c == '_' || c == '.')) {
return HANDLER_GO_ON;
}
}
if (r->conf.force_lowercase_filenames) {
for (size_t i = 0; i < ulen; ++i) {
if (light_isupper(u[i])) u[i] |= 0x20;
}
}
buffer_copy_buffer(b, p->conf.basepath);
if (p->conf.letterhomes) {
if (u[0] == '.') return HANDLER_GO_ON;
buffer_append_path_len(b, u, 1);
}
buffer_append_path_len(b, u, ulen);
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
buffer_append_path_len(b, BUF_PTR_LEN(p->conf.path));
}
buffer_copy_buffer(&r->physical.basedir, b);
buffer_copy_buffer(&r->physical.path, b);
/* the physical rel_path is basically the same as uri.path;
* but it is converted to lowercase in case of force_lowercase_filenames
* and some special handling for trailing '.', ' ' and '/' on windows
* we assume that no docroot/physical handler changed this
* (docroot should only set the docroot/server name, physical should only
* change the physical.path;
* the exception mod_secdownload doesn't work with userdir anyway)
*/
buffer_append_slash(&r->physical.path);
/* if no second '/' is found, we assume that it was stripped from the
* uri.path for the special handling on windows. we do not care about the
* trailing slash here on windows, as we already ensured it is a directory
*
* TODO: what to do with trailing dots in usernames on windows?
* they may result in the same directory as a username without them.
*/
char *rel_url;
if (NULL != (rel_url = strchr(r->physical.rel_path.ptr + 2, '/'))) {
buffer_append_string(&r->physical.path, rel_url + 1); /* skip the / */
}
return HANDLER_GO_ON;
}
URIHANDLER_FUNC(mod_userdir_docroot_handler) {
/* /~user/foo.html -> /home/user/public_html/foo.html */
#ifdef __COVERITY__
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
if (buffer_is_blank(&r->uri.path)) return HANDLER_GO_ON;
#endif
if (r->uri.path.ptr[0] != '/' ||
r->uri.path.ptr[1] != '~') return HANDLER_GO_ON;
plugin_data * const p = p_d;
mod_userdir_patch_config(r, p);
/* enforce the userdir.path to be set in the config, ugly fix for #1587;
* should be replaced with a clean .enabled option in 1.5
*/
[multiple] reduce redundant NULL buffer checks This commit is a large set of code changes and results in removal of hundreds, perhaps thousands, of CPU instructions, a portion of which are on hot code paths. Most (buffer *) used by lighttpd are not NULL, especially since buffers were inlined into numerous larger structs such as request_st and chunk. In the small number of instances where that is not the case, a NULL check is often performed earlier in a function where that buffer is later used with a buffer_* func. In the handful of cases that remained, a NULL check was added, e.g. with r->http_host and r->conf.server_tag. - check for empty strings at config time and set value to NULL if blank string will be ignored at runtime; at runtime, simple pointer check for NULL can be used to check for a value that has been set and is not blank ("") - use buffer_is_blank() instead of buffer_string_is_empty(), and use buffer_is_unset() instead of buffer_is_empty(), where buffer is known not to be NULL so that NULL check can be skipped - use buffer_clen() instead of buffer_string_length() when buffer is known not to be NULL (to avoid NULL check at runtime) - use buffer_truncate() instead of buffer_string_set_length() to truncate string, and use buffer_extend() to extend Examples where buffer known not to be NULL: - cpv->v.b from config_plugin_values_init is not NULL if T_CONFIG_BOOL (though we might set it to NULL if buffer_is_blank(cpv->v.b)) - address of buffer is arg (&foo) (compiler optimizer detects this in most, but not all, cases) - buffer is checked for NULL earlier in func - buffer is accessed in same scope without a NULL check (e.g. b->ptr) internal behavior change: callers must not pass a NULL buffer to some funcs. - buffer_init_buffer() requires non-null args - buffer_copy_buffer() requires non-null args - buffer_append_string_buffer() requires non-null args - buffer_string_space() requires non-null arg
1 year ago
if (!p->conf.active || !p->conf.path) return HANDLER_GO_ON;
const char * const uptr = r->uri.path.ptr + 2;
const char * const rel_url = strchr(uptr, '/');
if (NULL == rel_url) {
if (!*uptr) return HANDLER_GO_ON; /* "/~" is not a valid userdir path */
/* / is missing -> redirect to .../ as we are a user - DIRECTORY ! :) */
http_response_redirect_to_directory(r, 301);
return HANDLER_FINISHED;
}
/* /~/ is a empty username, catch it directly */
const size_t ulen = (size_t)(rel_url - uptr);
if (0 == ulen) return HANDLER_GO_ON;
/* vlists could be turned into sorted array at config time,
* but these lists are expected to be relatively short in most cases
* so there is not a huge benefit to doing so in the common case */
if (p->conf.exclude_user) {
/* use case-insensitive comparison for exclude list
* if r->conf.force_lowercase_filenames */
if (!r->conf.force_lowercase_filenames
? mod_userdir_in_vlist(p->conf.exclude_user, uptr, ulen)
: mod_userdir_in_vlist_nc(p->conf.exclude_user, uptr, ulen))
return HANDLER_GO_ON; /* user in exclude list */
}
if (p->conf.include_user) {
if (!mod_userdir_in_vlist(p->conf.include_user, uptr, ulen))
return HANDLER_GO_ON; /* user not in include list */
}
return mod_userdir_docroot_construct(r, p, uptr, ulen);
}
int mod_userdir_plugin_init(plugin *p);
int mod_userdir_plugin_init(plugin *p) {
p->version = LIGHTTPD_VERSION_ID;
p->name = "userdir";
p->init = mod_userdir_init;
p->cleanup = mod_userdir_free;
p->handle_physical = mod_userdir_docroot_handler;
p->set_defaults = mod_userdir_set_defaults;
return 0;
}