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lighttpd1.4/src/gw_backend.c

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/*
* gw_backend - gateway backend code shared by dynamic socket backends
*
* Copyright(c) 2017 Glenn Strauss gstrauss()gluelogic.com All rights reserved
* License: BSD 3-clause (same as lighttpd)
*/
#include "first.h"
#include "gw_backend.h"
#include <sys/types.h>
#include <sys/stat.h>
#include "sys-socket.h"
#ifdef HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdint.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include "base.h"
#include "algo_md.h"
#include "array.h"
#include "buffer.h"
#include "chunk.h"
#include "fdevent.h"
#include "http_header.h"
#include "log.h"
#include "sock_addr.h"
#include "status_counter.h"
__attribute_noinline__
static int * gw_status_get_counter(gw_host *host, gw_proc *proc, const char *tag, size_t tlen) {
/*(At the cost of some memory, could prepare strings for host and for proc
* so that here we would copy ready made string for proc (or if NULL,
* for host), and then append tag to produce key)*/
char label[288];
size_t llen = sizeof("gw.backend.")-1, len;
memcpy(label, "gw.backend.", llen);
len = buffer_clen(host->id);
if (len) {
force_assert(len < sizeof(label) - llen);
memcpy(label+llen, host->id->ptr, len);
llen += len;
}
if (proc) {
force_assert(llen < sizeof(label) - (LI_ITOSTRING_LENGTH + 1));
label[llen++] = '.';
len = li_utostrn(label+llen, LI_ITOSTRING_LENGTH, proc->id);
llen += len;
}
force_assert(tlen < sizeof(label) - llen);
memcpy(label+llen, tag, tlen);
llen += tlen;
label[llen] = '\0';
return status_counter_get_counter(label, llen);
}
static void gw_proc_tag_inc(gw_host *host, gw_proc *proc, const char *tag, size_t len) {
++(*gw_status_get_counter(host, proc, tag, len));
}
static void gw_proc_connected_inc(gw_host *host, gw_proc *proc) {
UNUSED(host);
++(*proc->stats_connected); /* "gw.backend...connected" */
}
static void gw_proc_load_inc(gw_host *host, gw_proc *proc) {
*proc->stats_load = ++proc->load; /* "gw.backend...load" */
++(*host->stats_global_active); /* "gw.active-requests" */
}
static void gw_proc_load_dec(gw_host *host, gw_proc *proc) {
*proc->stats_load = --proc->load; /* "gw.backend...load" */
--(*host->stats_global_active); /* "gw.active-requests" */
}
static void gw_host_assign(gw_host *host) {
*host->stats_load = ++host->load; /* "gw.backend...load" */
}
static void gw_host_reset(gw_host *host) {
*host->stats_load = --host->load; /* "gw.backend...load" */
}
static int gw_status_init(gw_host *host, gw_proc *proc) {
*gw_status_get_counter(host, proc, CONST_STR_LEN(".disabled")) = 0;
*gw_status_get_counter(host, proc, CONST_STR_LEN(".died")) = 0;
*gw_status_get_counter(host, proc, CONST_STR_LEN(".overloaded")) = 0;
proc->stats_connected =
gw_status_get_counter(host, proc, CONST_STR_LEN(".connected"));
*proc->stats_connected = 0;
proc->stats_load =
gw_status_get_counter(host, proc, CONST_STR_LEN(".load"));
*proc->stats_load = 0;
host->stats_load =
gw_status_get_counter(host, NULL, CONST_STR_LEN(".load"));
*host->stats_load = 0;
host->stats_global_active =
status_counter_get_counter(CONST_STR_LEN("gw.active-requests"));
return 0;
}
static void gw_proc_set_state(gw_host *host, gw_proc *proc, int state) {
if ((int)proc->state == state) return;
if (proc->state == PROC_STATE_RUNNING) {
--host->active_procs;
} else if (state == PROC_STATE_RUNNING) {
++host->active_procs;
}
proc->state = state;
}
static gw_proc *gw_proc_init(void) {
gw_proc *f = calloc(1, sizeof(*f));
force_assert(f);
/*f->unixsocket = buffer_init();*//*(init on demand)*/
f->connection_name = buffer_init();
f->prev = NULL;
f->next = NULL;
f->state = PROC_STATE_DIED;
return f;
}
static void gw_proc_free(gw_proc *f) {
if (!f) return;
gw_proc_free(f->next);
buffer_free(f->unixsocket);
buffer_free(f->connection_name);
free(f->saddr);
free(f);
}
static gw_host *gw_host_init(void) {
gw_host *f = calloc(1, sizeof(*f));
force_assert(f);
return f;
}
static void gw_host_free(gw_host *h) {
if (!h) return;
if (h->refcount) {
--h->refcount;
return;
}
gw_proc_free(h->first);
gw_proc_free(h->unused_procs);
for (uint32_t i = 0; i < h->args.used; ++i) free(h->args.ptr[i]);
free(h->args.ptr);
free(h);
}
static gw_exts *gw_extensions_init(void) {
gw_exts *f = calloc(1, sizeof(*f));
force_assert(f);
return f;
}
static void gw_extensions_free(gw_exts *f) {
if (!f) return;
for (uint32_t i = 0; i < f->used; ++i) {
gw_extension *fe = f->exts+i;
for (uint32_t j = 0; j < fe->used; ++j) {
gw_host_free(fe->hosts[j]);
}
free(fe->hosts);
}
free(f->exts);
free(f);
}
static int gw_extension_insert(gw_exts *ext, const buffer *key, gw_host *fh) {
gw_extension *fe = NULL;
for (uint32_t i = 0; i < ext->used; ++i) {
if (buffer_is_equal(key, &ext->exts[i].key)) {
fe = ext->exts+i;
break;
}
}
if (NULL == fe) {
if (ext->used == ext->size) {
ext->size += 8;
ext->exts = realloc(ext->exts, ext->size * sizeof(gw_extension));
force_assert(ext->exts);
memset(ext->exts + ext->used, 0, 8 * sizeof(gw_extension));
}
fe = ext->exts + ext->used++;
fe->last_used_ndx = -1;
buffer *b;
*(const buffer **)&b = &fe->key;
memcpy(b, key, sizeof(buffer)); /*(copy; not later free'd)*/
}
if (fe->size == fe->used) {
fe->size += 4;
fe->hosts = realloc(fe->hosts, fe->size * sizeof(*(fe->hosts)));
force_assert(fe->hosts);
}
fe->hosts[fe->used++] = fh;
return 0;
}
static void gw_proc_connect_success(gw_host *host, gw_proc *proc, int debug, request_st * const r) {
gw_proc_connected_inc(host, proc); /*(".connected")*/
proc->last_used = log_monotonic_secs;
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"got proc: pid: %d socket: %s load: %d",
proc->pid, proc->connection_name->ptr, proc->load);
}
}
__attribute_cold__
static void gw_proc_connect_error(request_st * const r, gw_host *host, gw_proc *proc, pid_t pid, int errnum, int debug) {
const time_t cur_ts = log_monotonic_secs;
log_error_st * const errh = r->conf.errh;
log_perror(errh, __FILE__, __LINE__, /*(caller should set errno = errnum)*/
"establishing connection failed: socket: %s", proc->connection_name->ptr);
if (!proc->is_local) {
proc->disabled_until = cur_ts + host->disable_time;
gw_proc_set_state(host, proc, PROC_STATE_OVERLOADED);
}
else if (proc->pid == pid && proc->state == PROC_STATE_RUNNING) {
/* several requests from lighttpd might reference the same proc
*
* Only one of them should mark the proc
* and all other ones should just take a new one.
*
* If a new proc was started with the old struct, this might
* otherwise lead to marking a perfectly good proc as dead
*/
log_error(errh, __FILE__, __LINE__,
"backend error; we'll disable for %d"
"secs and send the request to another backend instead:"
"load: %d", host->disable_time, host->load);
if (EAGAIN == errnum) {
/* - EAGAIN: cool down the backend; it is overloaded */
#ifdef __linux__
log_error(errh, __FILE__, __LINE__,
"If this happened on Linux: You have run out of local ports. "
"Check the manual, section Performance how to handle this.");
#endif
if (debug) {
log_error(errh, __FILE__, __LINE__,
"This means that you have more incoming requests than your "
"FastCGI backend can handle in parallel. It might help to "
"spawn more FastCGI backends or PHP children; if not, "
"decrease server.max-connections. The load for this FastCGI "
"backend %s is %d", proc->connection_name->ptr, proc->load);
}
proc->disabled_until = cur_ts + host->disable_time;
gw_proc_set_state(host, proc, PROC_STATE_OVERLOADED);
}
else {
/* we got a hard error from the backend like
* - ECONNREFUSED for tcp-ip sockets
* - ENOENT for unix-domain-sockets
*/
#if 0
gw_proc_set_state(host, proc, PROC_STATE_DIED_WAIT_FOR_PID);
#else /* treat as overloaded (future: unless we send kill() signal)*/
proc->disabled_until = cur_ts + host->disable_time;
gw_proc_set_state(host, proc, PROC_STATE_OVERLOADED);
#endif
}
}
if (EAGAIN == errnum) {
gw_proc_tag_inc(host, proc, CONST_STR_LEN(".overloaded"));
}
else {
gw_proc_tag_inc(host, proc, CONST_STR_LEN(".died"));
}
}
static void gw_proc_release(gw_host *host, gw_proc *proc, int debug, log_error_st *errh) {
gw_proc_load_dec(host, proc);
if (debug) {
log_error(errh, __FILE__, __LINE__,
"released proc: pid: %d socket: %s load: %u",
proc->pid, proc->connection_name->ptr, proc->load);
}
}
static void gw_proc_check_enable(gw_host * const host, gw_proc * const proc, log_error_st * const errh) {
if (log_monotonic_secs <= proc->disabled_until) return;
if (proc->state != PROC_STATE_OVERLOADED) return;
gw_proc_set_state(host, proc, PROC_STATE_RUNNING);
log_error(errh, __FILE__, __LINE__,
"gw-server re-enabled: %s %s %hu %s",
proc->connection_name->ptr,
host->host ? host->host->ptr : "", host->port,
host->unixsocket ? host->unixsocket->ptr : "");
}
static void gw_proc_waitpid_log(const gw_host * const host, const gw_proc * const proc, log_error_st * const errh, const int status) {
if (WIFEXITED(status)) {
if (proc->state != PROC_STATE_KILLED) {
log_error(errh, __FILE__, __LINE__,
"child exited: %d %s",
WEXITSTATUS(status), proc->connection_name->ptr);
}
} else if (WIFSIGNALED(status)) {
if (WTERMSIG(status) != SIGTERM && WTERMSIG(status) != SIGINT
&& WTERMSIG(status) != host->kill_signal) {
log_error(errh, __FILE__, __LINE__,
"child signalled: %d", WTERMSIG(status));
}
} else {
log_error(errh, __FILE__, __LINE__,
"child died somehow: %d", status);
}
}
static int gw_proc_waitpid(gw_host *host, gw_proc *proc, log_error_st *errh) {
int rc, status;
if (!proc->is_local) return 0;
if (proc->pid <= 0) return 0;
rc = fdevent_waitpid(proc->pid, &status, 1);
if (0 == rc) return 0; /* child still running */
/* child terminated */
if (-1 == rc) {
/* EINVAL or ECHILD no child processes */
/* should not happen; someone else has cleaned up for us */
log_perror(errh, __FILE__, __LINE__,
"pid %d %d not found", proc->pid, proc->state);
}
else {
gw_proc_waitpid_log(host, proc, errh, status);
}
proc->pid = 0;
if (proc->state != PROC_STATE_KILLED)
proc->disabled_until = log_monotonic_secs;
gw_proc_set_state(host, proc, PROC_STATE_DIED);
return 1;
}
static int gw_proc_sockaddr_init(gw_host * const host, gw_proc * const proc, log_error_st * const errh) {
sock_addr addr;
socklen_t addrlen;
if (proc->unixsocket) {
if (1 != sock_addr_from_str_hints(&addr,&addrlen,proc->unixsocket->ptr,
AF_UNIX, 0, errh)) {
errno = EINVAL;
return -1;
}
buffer_clear(proc->connection_name);
buffer_append_str2(proc->connection_name,
CONST_STR_LEN("unix:"),
BUF_PTR_LEN(proc->unixsocket));
}
else {
/*(note: name resolution here is *blocking* if IP string not supplied)*/
if (1 != sock_addr_from_str_hints(&addr, &addrlen, host->host->ptr,
0, proc->port, errh)) {
errno = EINVAL;
return -1;
}
else if (host->host->size) {
/*(skip if constant string set in gw_set_defaults_backend())*/
/* overwrite host->host buffer with IP addr string so that
* any further use of gw_host does not block on DNS lookup */
buffer *h;
*(const buffer **)&h = host->host;
sock_addr_inet_ntop_copy_buffer(h, &addr);
host->family = sock_addr_get_family(&addr);
}
buffer_clear(proc->connection_name);
buffer_append_str3(proc->connection_name,
CONST_STR_LEN("tcp:"),
BUF_PTR_LEN(host->host),
CONST_STR_LEN(":"));
buffer_append_int(proc->connection_name, proc->port);
}
if (NULL != proc->saddr && proc->saddrlen < addrlen) {
free(proc->saddr);
proc->saddr = NULL;
}
if (NULL == proc->saddr) {
proc->saddr = (struct sockaddr *)malloc(addrlen);
force_assert(proc->saddr);
}
proc->saddrlen = addrlen;
memcpy(proc->saddr, &addr, addrlen);
return 0;
}
static int env_add(char_array *env, const char *key, size_t key_len, const char *val, size_t val_len) {
char *dst;
if (!key || !val) return -1;
dst = malloc(key_len + val_len + 3);
force_assert(dst);
memcpy(dst, key, key_len);
dst[key_len] = '=';
memcpy(dst + key_len + 1, val, val_len + 1); /* add the \0 from the value */
for (uint32_t i = 0; i < env->used; ++i) {
#ifdef __COVERITY__
force_assert(env->ptr); /*(non-NULL if env->used != 0)*/
#endif
if (0 == strncmp(dst, env->ptr[i], key_len + 1)) {
free(env->ptr[i]);
env->ptr[i] = dst;
return 0;
}
}
if (env->size <= env->used + 1) {
env->size += 16;
env->ptr = realloc(env->ptr, env->size * sizeof(*env->ptr));
force_assert(env->ptr);
}
#ifdef __COVERITY__
force_assert(env->ptr); /*(non-NULL if env->used != 0; guaranteed above)*/
#endif
env->ptr[env->used++] = dst;
return 0;
}
static int gw_spawn_connection(gw_host * const host, gw_proc * const proc, log_error_st * const errh, int debug) {
int gw_fd;
int status;
struct timeval tv = { 0, 10 * 1000 };
if (debug) {
log_error(errh, __FILE__, __LINE__,
"new proc, socket: %hu %s",
proc->port, proc->unixsocket ? proc->unixsocket->ptr : "");
}
gw_fd = fdevent_socket_cloexec(proc->saddr->sa_family, SOCK_STREAM, 0);
if (-1 == gw_fd) {
log_perror(errh, __FILE__, __LINE__, "socket()");
return -1;
}
do {
status = connect(gw_fd, proc->saddr, proc->saddrlen);
} while (-1 == status && errno == EINTR);
if (-1 == status && errno != ENOENT && proc->unixsocket) {
log_perror(errh, __FILE__, __LINE__,
"unlink %s after connect failed", proc->unixsocket->ptr);
unlink(proc->unixsocket->ptr);
}
close(gw_fd);
if (-1 == status) {
/* server is not up, spawn it */
char_array env;
uint32_t i;
int dfd = -1;
/* reopen socket */
gw_fd = fdevent_socket_cloexec(proc->saddr->sa_family, SOCK_STREAM, 0);
if (-1 == gw_fd) {
log_perror(errh, __FILE__, __LINE__, "socket()");
return -1;
}
if (fdevent_set_so_reuseaddr(gw_fd, 1) < 0) {
log_perror(errh, __FILE__, __LINE__, "socketsockopt()");
close(gw_fd);
return -1;
}
/* create socket */
if (-1 == bind(gw_fd, proc->saddr, proc->saddrlen)) {
log_perror(errh, __FILE__, __LINE__,
"bind failed for: %s", proc->connection_name->ptr);
close(gw_fd);
return -1;
}
if (-1 == listen(gw_fd, host->listen_backlog)) {
log_perror(errh, __FILE__, __LINE__, "listen()");
close(gw_fd);
return -1;
}
{
/* create environment */
env.ptr = NULL;
env.size = 0;
env.used = 0;
/* build clean environment */
if (host->bin_env_copy && host->bin_env_copy->used) {
for (i = 0; i < host->bin_env_copy->used; ++i) {
data_string *ds=(data_string *)host->bin_env_copy->data[i];
char *ge;
if (NULL != (ge = getenv(ds->value.ptr))) {
env_add(&env, BUF_PTR_LEN(&ds->value), ge, strlen(ge));
}
}
} else {
char ** const e = fdevent_environ();
for (i = 0; e[i]; ++i) {
char *eq;
if (NULL != (eq = strchr(e[i], '='))) {
env_add(&env, e[i], eq - e[i], eq+1, strlen(eq+1));
}
}
}
/* create environment */
if (host->bin_env) {
for (i = 0; i < host->bin_env->used; ++i) {
data_string *ds = (data_string *)host->bin_env->data[i];
env_add(&env, BUF_PTR_LEN(&ds->key),
BUF_PTR_LEN(&ds->value));
}
}
for (i = 0; i < env.used; ++i) {
/* search for PHP_FCGI_CHILDREN */
if (0 == strncmp(env.ptr[i], "PHP_FCGI_CHILDREN=",
sizeof("PHP_FCGI_CHILDREN=")-1)) {
break;
}
}
/* not found, add a default */
if (i == env.used) {
env_add(&env, CONST_STR_LEN("PHP_FCGI_CHILDREN"),
CONST_STR_LEN("1"));
}
env.ptr[env.used] = NULL;
}
dfd = fdevent_open_dirname(host->args.ptr[0], 1); /* permit symlinks */
if (-1 == dfd) {
log_perror(errh, __FILE__, __LINE__,
"open dirname failed: %s", host->args.ptr[0]);
}
/*(FCGI_LISTENSOCK_FILENO == STDIN_FILENO == 0)*/
proc->pid = (dfd >= 0)
? fdevent_fork_execve(host->args.ptr[0], host->args.ptr,
env.ptr, gw_fd, -1, -1, dfd)
: -1;
for (i = 0; i < env.used; ++i) free(env.ptr[i]);
free(env.ptr);
if (-1 != dfd) close(dfd);
close(gw_fd);
if (-1 == proc->pid) {
log_error(errh, __FILE__, __LINE__,
"gw-backend failed to start: %s", host->bin_path->ptr);
proc->pid = 0;
proc->disabled_until = log_monotonic_secs;
return -1;
}
/* register process */
proc->last_used = log_monotonic_secs;
proc->is_local = 1;
/* wait */
select(0, NULL, NULL, NULL, &tv);
if (0 != gw_proc_waitpid(host, proc, errh)) {
log_error(errh, __FILE__, __LINE__,
"gw-backend failed to start: %s", host->bin_path->ptr);
log_error(errh, __FILE__, __LINE__,
"If you're trying to run your app as a FastCGI backend, make "
"sure you're using the FastCGI-enabled version. If this is PHP "
"on Gentoo, add 'fastcgi' to the USE flags. If this is PHP, try "
"removing the bytecode caches for now and try again.");
return -1;
}
} else {
proc->is_local = 0;
proc->pid = 0;
if (debug) {
log_error(errh, __FILE__, __LINE__,
"(debug) socket is already used; won't spawn: %s",
proc->connection_name->ptr);
}
}
gw_proc_set_state(host, proc, PROC_STATE_RUNNING);
return 0;
}
static void gw_proc_spawn(gw_host * const host, log_error_st * const errh, const int debug) {
gw_proc *proc;
for (proc = host->unused_procs; proc; proc = proc->next) {
/* (proc->pid <= 0 indicates PROC_STATE_DIED, not PROC_STATE_KILLED) */
if (proc->pid > 0) continue;
/* (do not attempt to spawn another proc if a proc just exited) */
if (proc->disabled_until >= log_monotonic_secs) return;
break;
}
if (proc) {
if (proc == host->unused_procs)
host->unused_procs = proc->next;
else
proc->prev->next = proc->next;
if (proc->next) {
proc->next->prev = proc->prev;
proc->next = NULL;
}
proc->prev = NULL;
} else {
proc = gw_proc_init();
proc->id = host->max_id++;
if (host->unixsocket)
proc->unixsocket = buffer_init();
}
++host->num_procs;
if (!host->unixsocket) {
proc->port = host->port + proc->id;
} else {
buffer_clear(proc->unixsocket);
buffer_append_str2(proc->unixsocket, BUF_PTR_LEN(host->unixsocket),
CONST_STR_LEN("-"));
buffer_append_int(proc->unixsocket, proc->id);
}
if (0 != gw_proc_sockaddr_init(host, proc, errh)) {
/*(should not happen if host->host validated at startup,
* and translated from name to IP address at startup)*/
log_error(errh, __FILE__, __LINE__,
"ERROR: spawning backend failed.");
--host->num_procs;
if (proc->id == host->max_id-1) --host->max_id;
gw_proc_free(proc);
} else if (gw_spawn_connection(host, proc, errh, debug)) {
log_error(errh, __FILE__, __LINE__,
"ERROR: spawning backend failed.");
proc->next = host->unused_procs;
if (host->unused_procs)
host->unused_procs->prev = proc;
host->unused_procs = proc;
} else {
proc->next = host->first;
if (host->first)
host->first->prev = proc;
host->first = proc;
}
}
static void gw_proc_kill(gw_host *host, gw_proc *proc) {
if (proc->next) proc->next->prev = proc->prev;
if (proc->prev) proc->prev->next = proc->next;
if (proc->prev == NULL) host->first = proc->next;
proc->prev = NULL;
proc->next = host->unused_procs;
proc->disabled_until = 0;
if (host->unused_procs)
host->unused_procs->prev = proc;
host->unused_procs = proc;
kill(proc->pid, host->kill_signal);
gw_proc_set_state(host, proc, PROC_STATE_KILLED);
--host->num_procs;
}
__attribute_pure__
static gw_host * unixsocket_is_dup(gw_plugin_data *p, const buffer *unixsocket) {
if (NULL == p->cvlist) return NULL;
/* (init i to 0 if global context; to 1 to skip empty global context) */
for (int i = !p->cvlist[0].v.u2[1], used = p->nconfig; i < used; ++i) {
config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0];
gw_plugin_config *conf = NULL;
for (; -1 != cpv->k_id; ++cpv) {
switch (cpv->k_id) {
case 0: /* xxxxx.server */
if (cpv->vtype == T_CONFIG_LOCAL) conf = cpv->v.v;
break;
default:
break;
}
}
if (NULL == conf || NULL == conf->exts) continue;
gw_exts *exts = conf->exts;
for (uint32_t j = 0; j < exts->used; ++j) {
gw_extension *ex = exts->exts+j;
for (uint32_t n = 0; n < ex->used; ++n) {
gw_host *host = ex->hosts[n];
if (host->unixsocket
&& buffer_is_equal(host->unixsocket, unixsocket)
&& host->bin_path)
return host;
}
}
}
return NULL;
}
static int parse_binpath(char_array *env, const buffer *b) {
char *start = b->ptr;
char c;
/* search for spaces */
for (size_t i = 0, used = buffer_clen(b); i < used; ++i) {
switch(b->ptr[i]) {
case ' ':
case '\t':
/* a WS, stop here and copy the argument */
if (env->size == env->used) {
env->size += 16;
env->ptr = realloc(env->ptr, env->size * sizeof(*env->ptr));
}
c = b->ptr[i];
b->ptr[i] = '\0';
env->ptr[env->used++] = strdup(start);
b->ptr[i] = c;
start = b->ptr + i + 1;
break;
default:
break;
}
}
if (env->size == env->used) { /*need one extra for terminating NULL*/
env->size += 16;
env->ptr = realloc(env->ptr, env->size * sizeof(*env->ptr));
}
/* the rest */
env->ptr[env->used++] = strdup(start);
if (env->size == env->used) { /*need one extra for terminating NULL*/
env->size += 16;
env->ptr = realloc(env->ptr, env->size * sizeof(*env->ptr));
}
/* terminate */
env->ptr[env->used++] = NULL;
return 0;
}
enum {
GW_BALANCE_LEAST_CONNECTION,
GW_BALANCE_RR,
GW_BALANCE_HASH,
GW_BALANCE_STICKY
};
__attribute_noinline__
static uint32_t
gw_hash(const char *str, const uint32_t len, uint32_t hash)
{
return djbhash(str, len, hash);
}
static gw_host * gw_host_get(request_st * const r, gw_extension *extension, int balance, int debug) {
gw_host *host;
buffer *dst_addr_buf;
uint32_t last_max = UINT32_MAX;
uint32_t base_hash = DJBHASH_INIT;
int max_usage = INT_MAX;
int ndx = -1;
uint32_t k;
if (extension->used <= 1) {
if (1 == extension->used && extension->hosts[0]->active_procs > 0) {
ndx = 0;
}
} else switch(balance) {
case GW_BALANCE_HASH:
/* hash balancing */
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"proxy - used hash balancing, hosts: %u", extension->used);
}
base_hash = gw_hash(BUF_PTR_LEN(&r->uri.path), base_hash);
base_hash = gw_hash(BUF_PTR_LEN(&r->uri.authority), base_hash);
for (k = 0, ndx = -1, last_max = UINT32_MAX; k < extension->used; ++k) {
uint32_t cur_max;
host = extension->hosts[k];
if (0 == host->active_procs) continue;
/* future: hash of host->host could be cached separately, mixed in*/
cur_max = host->host
? gw_hash(BUF_PTR_LEN(host->host), base_hash)
: base_hash;
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"proxy - election: %s %s %s %u", r->uri.path.ptr,
host->host ? host->host->ptr : "",
r->uri.authority.ptr, cur_max);
}
if (last_max < cur_max || last_max == UINT32_MAX) {
last_max = cur_max;
ndx = k;
}
}
break;
case GW_BALANCE_LEAST_CONNECTION:
/* fair balancing */
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"proxy - used least connection");
}
for (k = 0, ndx = -1, max_usage = INT_MAX; k < extension->used; ++k) {
host = extension->hosts[k];
if (0 == host->active_procs) continue;
if (host->load < max_usage) {
max_usage = host->load;
ndx = k;
}
}
break;
case GW_BALANCE_RR:
/* round robin */
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"proxy - used round-robin balancing");
}
/* just to be sure */
force_assert(extension->used < INT_MAX);
host = extension->hosts[0];
/* Use last_used_ndx from first host in list */
k = extension->last_used_ndx;
ndx = k + 1; /* use next host after the last one */
if (ndx < 0) ndx = 0;
/* Search first active host after last_used_ndx */
while (ndx < (int) extension->used
&& 0 == (host = extension->hosts[ndx])->active_procs) ++ndx;
if (ndx >= (int) extension->used) {
/* didn't find a higher id, wrap to the start */
for (ndx = 0; ndx <= (int) k; ++ndx) {
host = extension->hosts[ndx];
if (0 != host->active_procs) break;
}
/* No active host found */
if (0 == host->active_procs) ndx = -1;
}
/* Save new index for next round */
extension->last_used_ndx = ndx;
break;
case GW_BALANCE_STICKY:
/* source sticky balancing */
dst_addr_buf = r->con->dst_addr_buf;
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"proxy - used sticky balancing, hosts: %u", extension->used);
}
base_hash = gw_hash(BUF_PTR_LEN(dst_addr_buf), base_hash);
for (k = 0, ndx = -1, last_max = UINT32_MAX; k < extension->used; ++k) {
unsigned long cur_max;
host = extension->hosts[k];
if (0 == host->active_procs) continue;
/* future: hash of host->host could be cached separately, mixed in*/
cur_max = host->host
? gw_hash(BUF_PTR_LEN(host->host), base_hash)
: base_hash;
cur_max += host->port;
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"proxy - election: %s %s %hu %ld", dst_addr_buf->ptr,
host->host ? host->host->ptr : "",
host->port, cur_max);
}
if (last_max < cur_max || last_max == UINT32_MAX) {
last_max = cur_max;
ndx = k;
}
}
break;
default:
break;
}
if (-1 != ndx) {
/* found a server */
host = extension->hosts[ndx];
if (debug) {
log_error(r->conf.errh, __FILE__, __LINE__,
"gw - found a host %s %hu",
host->host ? host->host->ptr : "", host->port);
}
return host;
} else if (0 == r->con->srv->srvconf.max_worker) {
/* special-case adaptive spawning and 0 == host->min_procs */
for (k = 0; k < extension->used; ++k) {
host = extension->hosts[k];
if (0 == host->min_procs && 0 == host->num_procs && host->bin_path){
gw_proc_spawn(host, r->con->srv->errh, debug);
if (host->num_procs) return host;
}
}
}
/* all hosts are down */
/* sorry, we don't have a server alive for this ext */
r->http_status = 503; /* Service Unavailable */
r->handler_module = NULL;
/* only send the 'no handler' once */
if (!extension->note_is_sent) {
extension->note_is_sent = 1;
log_error(r->conf.errh, __FILE__, __LINE__,
"all handlers for %s?%.*s on %s are down.",
r->uri.path.ptr, BUFFER_INTLEN_PTR(&r->uri.query),
extension->key.ptr);
}
return NULL;
}
static int gw_establish_connection(request_st * const r, gw_host *host, gw_proc *proc, pid_t pid, int gw_fd, int debug) {
if (-1 == connect(gw_fd, proc->saddr, proc->saddrlen)) {
if (errno == EINPROGRESS || errno == EALREADY || errno == EINTR
|| (errno == EAGAIN && host->unixsocket)) {
if (debug > 2) {
log_error(r->conf.errh, __FILE__, __LINE__,
"connect delayed; will continue later: %s",
proc->connection_name->ptr);
}
return 1;
} else {
gw_proc_connect_error(r, host, proc, pid, errno, debug);
return -1;
}
}
if (debug > 1) {
log_error(r->conf.errh, __FILE__, __LINE__,
"connect succeeded: %d", gw_fd);
}
return 0;
}
static void gw_restart_dead_procs(gw_host * const host, log_error_st * const errh, const int debug, const int trigger) {
for (gw_proc *proc = host->first; proc; proc = proc->next) {
if (debug > 2) {
log_error(errh, __FILE__, __LINE__,
"proc: %s %d %d %d %d", proc->connection_name->ptr,
proc->state, proc->is_local, proc->load, proc->pid);
}
switch (proc->state) {
case PROC_STATE_RUNNING:
break;
case PROC_STATE_OVERLOADED:
gw_proc_check_enable(host, proc, errh);
break;
case PROC_STATE_KILLED:
if (trigger && ++proc->disabled_until > 4) {
int sig = (proc->disabled_until <= 8)
? host->kill_signal
: proc->disabled_until <= 16 ? SIGTERM : SIGKILL;
kill(proc->pid, sig);
}
break;
case PROC_STATE_DIED_WAIT_FOR_PID:
/*(state should not happen in workers if server.max-worker > 0)*/
/*(if PROC_STATE_DIED_WAIT_FOR_PID is used in future, might want
* to save proc->disabled_until before gw_proc_waitpid() since
* gw_proc_waitpid will set proc->disabled_until=log_monotonic_secs,
* and so process will not be restarted below until one sec later)*/
if (0 == gw_proc_waitpid(host, proc, errh)) {
gw_proc_check_enable(host, proc, errh);
}
if (proc->state != PROC_STATE_DIED) break;
__attribute_fallthrough__/*(we have a dead proc now)*/
case PROC_STATE_DIED:
/* local procs get restarted by us,
* remote ones hopefully by the admin */
if (host->bin_path) {
/* we still have connections bound to this proc,
* let them terminate first */
if (proc->load != 0) break;
/* avoid spinning if child exits too quickly */
if (proc->disabled_until >= log_monotonic_secs) break;
/* restart the child */
if (debug) {
log_error(errh, __FILE__, __LINE__,
"--- gw spawning"
"\n\tsocket %s"
"\n\tcurrent: 1 / %u",
proc->connection_name->ptr, host->max_procs);
}
if (gw_spawn_connection(host, proc, errh, debug)) {
log_error(errh, __FILE__, __LINE__,
"ERROR: spawning gw failed.");
}
} else {
gw_proc_check_enable(host, proc, errh);
}
break;
}
}
}
#include "base.h"
#include "connections.h"
#include "response.h"
/* ok, we need a prototype */
static handler_t gw_handle_fdevent(void *ctx, int revents);
static gw_handler_ctx * handler_ctx_init(size_t sz) {
gw_handler_ctx *hctx = calloc(1, 0 == sz ? sizeof(*hctx) : sz);
force_assert(hctx);
/*hctx->response = chunk_buffer_acquire();*//*(allocated when needed)*/
hctx->request_id = 0;
hctx->gw_mode = GW_RESPONDER;
hctx->state = GW_STATE_INIT;
hctx->proc = NULL;
hctx->fd = -1;
hctx->reconnects = 0;
hctx->send_content_body = 1;
/*hctx->rb = chunkqueue_init();*//*(allocated when needed)*/
chunkqueue_init(&hctx->wb);
hctx->wb_reqlen = 0;
return hctx;
}
static void handler_ctx_free(gw_handler_ctx *hctx) {
/* caller MUST have called gw_backend_close(hctx, r) if necessary */
if (hctx->handler_ctx_free) hctx->handler_ctx_free(hctx);
chunk_buffer_release(hctx->response);
if (hctx->rb) chunkqueue_free(hctx->rb);
chunkqueue_reset(&hctx->wb);
free(hctx);
}
static void handler_ctx_clear(gw_handler_ctx *hctx) {
/* caller MUST have called gw_backend_close(hctx, r) if necessary */
hctx->proc = NULL;
hctx->host = NULL;
hctx->ext = NULL;
/*hctx->ext_auth is intentionally preserved to flag prior authorizer*/
hctx->gw_mode = GW_RESPONDER;
hctx->state = GW_STATE_INIT;
/*hctx->state_timestamp = 0;*//*(unused; left as-is)*/
if (hctx->rb) chunkqueue_reset(hctx->rb);
chunkqueue_reset(&hctx->wb);
hctx->wb_reqlen = 0;
if (hctx->response) buffer_clear(hctx->response);
hctx->fd = -1;
hctx->reconnects = 0;
hctx->request_id = 0;
hctx->send_content_body = 1;
/*plugin_config conf;*//*(no need to reset for same request)*/
/*hctx->r = NULL;*//*(no need to reset for same request)*/
/*hctx->plugin_data = NULL;*//*(no need to reset for same request)*/
}
void * gw_init(void) {
return calloc(1, sizeof(gw_plugin_data));
}
void gw_plugin_config_free(gw_plugin_config *s) {
gw_exts *exts = s->exts;
if (exts) {
for (uint32_t j = 0; j < exts->used; ++j) {
gw_extension *ex = exts->exts+j;
for (uint32_t n = 0; n < ex->used; ++n) {
gw_proc *proc;
gw_host *host = ex->hosts[n];
for (proc = host->first; proc; proc = proc->next) {
if (proc->pid > 0) {
kill(proc->pid, host->kill_signal);
}
if (proc->is_local && proc->unixsocket) {
unlink(proc->unixsocket->ptr);
}
}
for (proc = host->unused_procs; proc; proc = proc->next) {
if (proc->pid > 0) {
kill(proc->pid, host->kill_signal);
}
if (proc->is_local && proc->unixsocket) {
unlink(proc->unixsocket->ptr);
}
}
}
}
gw_extensions_free(s->exts);
gw_extensions_free(s->exts_auth);
gw_extensions_free(s->exts_resp);
}
free(s);
}
void gw_free(void *p_d) {
gw_plugin_data * const p = p_d;
if (NULL == p->cvlist) return;
/* (init i to 0 if global context; to 1 to skip empty global context) */
for (int i = !p->cvlist[0].v.u2[1], used = p->nconfig; i < used; ++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: /* xxxxx.server */
if (cpv->vtype == T_CONFIG_LOCAL)
gw_plugin_config_free(cpv->v.v);
break;
default:
break;
}
}
}
}
void gw_exts_clear_check_local(gw_exts *exts) {
for (uint32_t j = 0; j < exts->used; ++j) {
gw_extension *ex = exts->exts+j;
for (uint32_t n = 0; n < ex->used; ++n) {
ex->hosts[n]->check_local = 0;
}
}
}
int gw_set_defaults_backend(server *srv, gw_plugin_data *p, const array *a, gw_plugin_config *s, int sh_exec, const char *cpkkey) {
/* per-module plugin_config MUST have common "base class" gw_plugin_config*/
/* per-module plugin_data MUST have pointer-compatible common "base class"
* with gw_plugin_data (stemming from gw_plugin_config compatibility) */
static const config_plugin_keys_t cpk[] = {
{ CONST_STR_LEN("host"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("port"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("socket"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("listen-backlog"),
T_CONFIG_INT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("bin-path"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("kill-signal"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("check-local"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("mode"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("docroot"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("min-procs"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("max-procs"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("max-load-per-proc"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("idle-timeout"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("disable-time"),
T_CONFIG_SHORT,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("bin-environment"),
T_CONFIG_ARRAY_KVSTRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("bin-copy-environment"),
T_CONFIG_ARRAY_VLIST,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("broken-scriptfilename"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("strip-request-uri"),
T_CONFIG_STRING,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("fix-root-scriptname"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("allow-x-send-file"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("x-sendfile"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("x-sendfile-docroot"),
T_CONFIG_ARRAY_VLIST,
T_CONFIG_SCOPE_CONNECTION }
,{ CONST_STR_LEN("tcp-fin-propagate"),
T_CONFIG_BOOL,
T_CONFIG_SCOPE_CONNECTION }
,{ NULL, 0,
T_CONFIG_UNSET,
T_CONFIG_SCOPE_UNSET }
};
gw_host *host = NULL;
p->srv_pid = srv->pid;
s->exts = gw_extensions_init();
s->exts_auth = gw_extensions_init();
s->exts_resp = gw_extensions_init();
/*s->balance = GW_BALANCE_LEAST_CONNECTION;*//*(default)*/
/*
* gw.server = ( "<ext>" => ( ... ),
* "<ext>" => ( ... ) )
*/
for (uint32_t j = 0; j < a->used; ++j) {
data_array *da_ext = (data_array *)a->data[j];
/*
* da_ext->key == name of the extension
*/
/*
* gw.server = ( "<ext>" =>
* ( "<host>" => ( ... ),
* "<host>" => ( ... )
* ),
* "<ext>" => ... )
*/
for (uint32_t n = 0; n < da_ext->value.used; ++n) {
data_array * const da_host = (data_array *)da_ext->value.data[n];
if (da_host->type != TYPE_ARRAY
|| !array_is_kvany(&da_host->value)){
log_error(srv->errh, __FILE__, __LINE__,
"unexpected value for gw.server near [%s](string); "
"expected ( \"ext\" => "
"( \"backend-label\" => ( \"key\" => \"value\" )))",
da_host->key.ptr ? da_host->key.ptr : "");
goto error;
}
config_plugin_value_t cvlist[sizeof(cpk)/sizeof(cpk[0])+1];
memset(cvlist, 0, sizeof(cvlist));
array *ca = &da_host->value;
if (!config_plugin_values_init_block(srv, ca, cpk, cpkkey, cvlist))
goto error;
unsigned short host_mode = GW_RESPONDER;
host = gw_host_init();
host->id = &da_host->key;
host->check_local = 1;
host->min_procs = 4;
host->max_procs = 4;
host->max_load_per_proc = 1;
host->idle_timeout = 60;
host->disable_time = 1;
host->break_scriptfilename_for_php = 0;
host->kill_signal = SIGTERM;
host->fix_root_path_name = 0;
host->listen_backlog = 1024;
host->xsendfile_allow = 0;
host->refcount = 0;
config_plugin_value_t *cpv = cvlist;
for (; -1 != cpv->k_id; ++cpv) {
switch (cpv->k_id) {
case 0: /* host */
if (!buffer_is_blank(cpv->v.b))
host->host = cpv->v.b;
break;
case 1: /* port */
host->port = cpv->v.shrt;
break;
case 2: /* socket */
if (!buffer_is_blank(cpv->v.b))
host->unixsocket = cpv->v.b;
break;
case 3: /* listen-backlog */
host->listen_backlog = cpv->v.u;
break;
case 4: /* bin-path */
if (!buffer_is_blank(cpv->v.b))
host->bin_path = cpv->v.b;
break;
case 5: /* kill-signal */
host->kill_signal = cpv->v.shrt;
break;
case 6: /* check-local */
host->check_local = (0 != cpv->v.u);
break;
case 7: /* mode */
if (!buffer_is_blank(cpv->v.b)) {
const buffer *b = cpv->v.b;
if (buffer_eq_slen(b, CONST_STR_LEN("responder")))
host_mode = GW_RESPONDER;
else if (buffer_eq_slen(b, CONST_STR_LEN("authorizer")))
host_mode = GW_AUTHORIZER;
else
log_error(srv->errh, __FILE__, __LINE__,
"WARNING: unknown gw mode: %s "
"(ignored, mode set to responder)", b->ptr);
}
break;
case 8: /* docroot */
if (!buffer_is_blank(cpv->v.b))
host->docroot = cpv->v.b;
break;
case 9: /* min-procs */
host->min_procs = cpv->v.shrt;
break;
case 10:/* max-procs */
host->max_procs = cpv->v.shrt;
break;
case 11:/* max-load-per-proc */
host->max_load_per_proc = cpv->v.shrt;
break;
case 12:/* idle-timeout */
host->idle_timeout = cpv->v.shrt;
break;
case 13:/* disable-time */
host->disable_time = cpv->v.shrt;
break;
case 14:/* bin-environment */
host->bin_env = cpv->v.a;
break;
case 15:/* bin-copy-environment */
host->bin_env_copy = cpv->v.a;
break;
case 16:/* broken-scriptfilename */
host->break_scriptfilename_for_php = (0 != cpv->v.u);
break;
case 17:/* strip-request-uri */
host->strip_request_uri = cpv->v.b;
if (buffer_has_slash_suffix(host->strip_request_uri)) {
buffer *b; /*(remove trailing slash; see http_cgi.c)*/
*(const buffer **)&b = host->strip_request_uri;
buffer_truncate(b, buffer_clen(b)-1);
}
break;
case 18:/* fix-root-scriptname */
host->fix_root_path_name = (0 != cpv->v.u);
break;
case 19:/* allow-x-send-file */
host->xsendfile_allow = (0 != cpv->v.u);
break;
case 20:/* x-sendfile */
host->xsendfile_allow = (0 != cpv->v.u);
break;
case 21:/* x-sendfile-docroot */
host->xsendfile_docroot = cpv->v.a;
if (cpv->v.a->used) {
for (uint32_t k = 0; k < cpv->v.a->used; ++k) {
data_string *ds = (data_string *)cpv->v.a->data[k];
if (ds->type != TYPE_STRING) {
log_error(srv->errh, __FILE__, __LINE__,
"unexpected type for x-sendfile-docroot; "
"expected: \"x-sendfile-docroot\" => "
"( \"/allowed/path\", ... )");
goto error;
}
if (ds->value.ptr[0] != '/') {
log_error(srv->errh, __FILE__, __LINE__,
"x-sendfile-docroot paths must begin with "
"'/'; invalid: \"%s\"", ds->value.ptr);
goto error;
}
buffer_path_simplify(&ds->value);
buffer_append_slash(&ds->value);
}
}
break;
case 22:/* tcp-fin-propagate */
host->tcp_fin_propagate = (0 != cpv->v.u);
break;
default:
break;
}
}
for (uint32_t m = 0; m < da_host->value.used; ++m) {
if (NULL != strchr(da_host->value.data[m]->key.ptr, '_')) {
log_error(srv->errh, __FILE__, __LINE__,
"incorrect directive contains underscore ('_') instead of dash ('-'): %s",
da_host->value.data[m]->key.ptr);
}
}
if ((host->host || host->port) && host->unixsocket) {
log_error(srv->errh, __FILE__, __LINE__,
"either host/port or socket have to be set in: "
"%s = (%s => (%s ( ...", cpkkey, da_ext->key.ptr,
da_host->key.ptr);
goto error;
}
if (host->host && *host->host->ptr == '/' && !host->unixsocket) {
host->unixsocket = host->host;
}
if (host->unixsocket) {
/* unix domain socket */
struct sockaddr_un un;
if (buffer_clen(host->unixsocket) + 1 > sizeof(un.sun_path) - 2) {
log_error(srv->errh, __FILE__, __LINE__,
"unixsocket is too long in: %s = (%s => (%s ( ...",
cpkkey, da_ext->key.ptr, da_host->key.ptr);
goto error;
}
if (host->bin_path) {
gw_host *duplicate = unixsocket_is_dup(p, host->unixsocket);
if (NULL != duplicate) {
if (!buffer_is_equal(host->bin_path, duplicate->bin_path)) {
log_error(srv->errh, __FILE__, __LINE__,
"duplicate unixsocket path: %s",
host->unixsocket->ptr);
goto error;
}
gw_host_free(host);
host = duplicate;
++host->refcount;
}
}
host->family = AF_UNIX;
} else {
/* tcp/ip */
if (!host->host && !host->bin_path) {
log_error(srv->errh, __FILE__, __LINE__,
"host or bin-path have to be set in: "
"%s = (%s => (%s ( ...", cpkkey, da_ext->key.ptr,
da_host->key.ptr);
goto error;
} else if (0 == host->port) {
host->port = 80;
}
if (!host->host) {
static const buffer lhost ={CONST_STR_LEN("127.0.0.1")+1,0};
host->host = &lhost;
}
host->family = (NULL != strchr(host->host->ptr, ':'))
? AF_INET6
: AF_INET;
}
if (host->refcount) {
/* already init'd; skip spawning */
} else if (host->bin_path) {
/* a local socket + self spawning */
struct stat st;
parse_binpath(&host->args, host->bin_path);
if (0 != stat(host->args.ptr[0], &st) || !S_ISREG(st.st_mode)
|| !(st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))) {
log_error(srv->errh, __FILE__, __LINE__,
"invalid \"bin-path\" => \"%s\" "
"(check that file exists, is regular file, "
"and is executable by lighttpd)", host->bin_path->ptr);
}
if (sh_exec) {
/*(preserve prior behavior for SCGI exec of command)*/
/*(admin should really prefer to put
* any complex command into a script)*/
for (uint32_t m = 0; m < host->args.used; ++m)
free(host->args.ptr[m]);
free(host->args.ptr);
host->args.ptr = calloc(4, sizeof(char *));
force_assert(host->args.ptr);
host->args.used = 3;
host->args.size = 4;
host->args.ptr[0] = malloc(sizeof("/bin/sh"));
force_assert(host->args.ptr[0]);
memcpy(host->args.ptr[0], "/bin/sh", sizeof("/bin/sh"));
host->args.ptr[1] = malloc(sizeof("-c"));
force_assert(host->args.ptr[1]);
memcpy(host->args.ptr[1], "-c", sizeof("-c"));
host->args.ptr[2] =
malloc(sizeof("exec ")-1+buffer_clen(host->bin_path)+1);
force_assert(host->args.ptr[2]);
memcpy(host->args.ptr[2], "exec ", sizeof("exec ")-1);
memcpy(host->args.ptr[2]+sizeof("exec ")-1,
host->bin_path->ptr, buffer_clen(host->bin_path)+1);
host->args.ptr[3] = NULL;
}
if (host->min_procs > host->max_procs)
host->min_procs = host->max_procs;
if (host->min_procs!= host->max_procs
&& 0 != srv->srvconf.max_worker) {
host->min_procs = host->max_procs;
log_error(srv->errh, __FILE__, __LINE__,
"adaptive backend spawning disabled "
"(server.max_worker is non-zero)");
}
if (host->max_load_per_proc < 1)
host->max_load_per_proc = 0;
if (s->debug) {
log_error(srv->errh, __FILE__, __LINE__,
"--- gw spawning local"
"\n\tproc: %s"
"\n\tport: %hu"
"\n\tsocket %s"
"\n\tmin-procs: %d"
"\n\tmax-procs: %d",
host->bin_path->ptr,
host->port,
host->unixsocket ? host->unixsocket->ptr : "",
host->min_procs,
host->max_procs);
}
for (uint32_t pno = 0; pno < host->min_procs; ++pno) {
gw_proc *proc = gw_proc_init();
proc->id = host->num_procs++;
host->max_id++;
if (!host->unixsocket) {
proc->port = host->port + pno;
} else {
proc->unixsocket = buffer_init();
buffer_append_str2(proc->unixsocket,
BUF_PTR_LEN(host->unixsocket),
CONST_STR_LEN("-"));
buffer_append_int(proc->unixsocket, pno);
}
if (s->debug) {
log_error(srv->errh, __FILE__, __LINE__,
"--- gw spawning"
"\n\tport: %hu"
"\n\tsocket %s"
"\n\tcurrent: %u / %u",
host->port,
host->unixsocket ? host->unixsocket->ptr : "",
pno, host->max_procs);
}
if (0 != gw_proc_sockaddr_init(host, proc, srv->errh)) {
gw_proc_free(proc);
goto error;
}
if (!srv->srvconf.preflight_check
&& gw_spawn_connection(host, proc, srv->errh, s->debug)) {
log_error(srv->errh, __FILE__, __LINE__,
"[ERROR]: spawning gw failed.");
gw_proc_free(proc);
goto error;
}
gw_status_init(host, proc);
proc->next = host->first;
if (host->first) host->first->prev = proc;
host->first = proc;
}
} else {
gw_proc *proc;
proc = gw_proc_init();
proc->id = host->num_procs++;
host->max_id++;
gw_proc_set_state(host, proc, PROC_STATE_RUNNING);
if (!host->unixsocket) {
proc->port = host->port;
} else {
proc->unixsocket = buffer_init();
buffer_copy_buffer(proc->unixsocket, host->unixsocket);
}
gw_status_init(host, proc);
host->first = proc;
host->min_procs = 1;
host->max_procs = 1;
if (0 != gw_proc_sockaddr_init(host, proc, srv->errh)) goto error;
}
/* s->exts is list of exts -> hosts
* s->exts now used as combined list
* of authorizer and responder hosts (for backend maintenance)
* s->exts_auth is list of exts -> authorizer hosts
* s->exts_resp is list of exts -> responder hosts
* For each path/extension:
* there may be an independent GW_AUTHORIZER and GW_RESPONDER
* (The GW_AUTHORIZER and GW_RESPONDER could be handled by the same
* host, and an admin might want to do that for large uploads,
* since GW_AUTHORIZER runs prior to receiving (potentially large)
* request body from client and can authorizer or deny request
* prior to receiving the full upload)
*/
gw_extension_insert(s->exts, &da_ext->key, host);
if (host_mode == GW_AUTHORIZER) {
++host->refcount;
gw_extension_insert(s->exts_auth, &da_ext->key, host);
} else if (host_mode == GW_RESPONDER) {
++host->refcount;
gw_extension_insert(s->exts_resp, &da_ext->key, host);
} /*(else should have been rejected above)*/
host = NULL;
}
}
return 1;
error:
if (NULL != host) gw_host_free(host);
return 0;
}
int gw_get_defaults_balance(server *srv, const buffer *b) {
if (!b || buffer_is_blank(b))
return GW_BALANCE_LEAST_CONNECTION;
if (buffer_eq_slen(b, CONST_STR_LEN("fair")))
return GW_BALANCE_LEAST_CONNECTION;
if (buffer_eq_slen(b, CONST_STR_LEN("least-connection")))
return GW_BALANCE_LEAST_CONNECTION;
if (buffer_eq_slen(b, CONST_STR_LEN("round-robin")))
return GW_BALANCE_RR;
if (buffer_eq_slen(b, CONST_STR_LEN("hash")))
return GW_BALANCE_HASH;
if (buffer_eq_slen(b, CONST_STR_LEN("sticky")))
return GW_BALANCE_STICKY;
log_error(srv->errh, __FILE__, __LINE__,
"xxxxx.balance has to be one of: "
"least-connection, round-robin, hash, sticky, but not: %s", b->ptr);
return GW_BALANCE_LEAST_CONNECTION;
}
static void gw_set_state(gw_handler_ctx *hctx, gw_connection_state_t state) {
hctx->state = state;
/*hctx->state_timestamp = log_monotonic_secs;*/
}
void gw_set_transparent(gw_handler_ctx *hctx) {
if (AF_UNIX != hctx->host->family) {
if (-1 == fdevent_set_tcp_nodelay(hctx->fd, 1)) {
/*(error, but not critical)*/
}
}
hctx->wb_reqlen = -1;
gw_set_state(hctx, GW_STATE_WRITE);
}
static void gw_backend_close(gw_handler_ctx * const hctx, request_st * const r) {
if (hctx->fd >= 0) {
fdevent_fdnode_event_del(hctx->ev, hctx->fdn);
/*fdevent_unregister(ev, hctx->fd);*//*(handled below)*/
fdevent_sched_close(hctx->ev, hctx->fd, 1);
hctx->fdn = NULL;
hctx->fd = -1;
}
if (hctx->host) {
if (hctx->proc) {
gw_proc_release(hctx->host, hctx->proc, hctx->conf.debug,
r->conf.errh);
hctx->proc = NULL;
}
gw_host_reset(hctx->host);
hctx->host = NULL;
}
}
static void gw_connection_close(gw_handler_ctx * const hctx, request_st * const r) {
gw_plugin_data *p = hctx->plugin_data;
gw_backend_close(hctx, r);
handler_ctx_free(hctx);
r->plugin_ctx[p->id] = NULL;
if (r->handler_module == p->self) {
http_response_backend_done(r);
}
}
static handler_t gw_reconnect(gw_handler_ctx * const hctx, request_st * const r) {
gw_backend_close(hctx, r);
hctx->host = gw_host_get(r,hctx->ext,hctx->conf.balance,hctx->conf.debug);
if (NULL == hctx->host) return HANDLER_FINISHED;
gw_host_assign(hctx->host);
hctx->request_id = 0;
hctx->opts.xsendfile_allow = hctx->host->xsendfile_allow;
hctx->opts.xsendfile_docroot = hctx->host->xsendfile_docroot;
gw_set_state(hctx, GW_STATE_INIT);
return HANDLER_COMEBACK;
}
handler_t gw_handle_request_reset(request_st * const r, void *p_d) {
gw_plugin_data *p = p_d;
gw_handler_ctx *hctx = r->plugin_ctx[p->id];
if (hctx) gw_connection_close(hctx, r);
return HANDLER_GO_ON;
}
static void gw_conditional_tcp_fin(gw_handler_ctx * const hctx, request_st * const r) {
/*assert(r->conf.stream_request_body & FDEVENT_STREAM_REQUEST_TCP_FIN);*/
if (!chunkqueue_is_empty(&hctx->wb))return;
if (!hctx->host->tcp_fin_propagate) return;
if (hctx->gw_mode == GW_AUTHORIZER) return;
if (r->conf.stream_request_body & FDEVENT_STREAM_REQUEST_BACKEND_SHUT_WR)
return;
/* propagate shutdown SHUT_WR to backend if TCP half-close on con->fd */
r->conf.stream_request_body |= FDEVENT_STREAM_REQUEST_BACKEND_SHUT_WR;
r->conf.stream_request_body &= ~FDEVENT_STREAM_REQUEST_POLLIN;
r->con->is_readable = 0;
shutdown(hctx->fd, SHUT_WR);
fdevent_fdnode_event_clr(hctx->ev, hctx->fdn, FDEVENT_OUT);
}
static handler_t gw_write_request(gw_handler_ctx * const hctx, request_st * const r) {
switch(hctx->state) {
case GW_STATE_INIT:
/* do we have a running process for this host (max-procs) ? */
hctx->proc = NULL;
for (gw_proc *proc = hctx->host->first; proc; proc = proc->next) {
if (proc->state == PROC_STATE_RUNNING) {
hctx->proc = proc;
break;
}
}
/* all children are dead */
if (hctx->proc == NULL) {
return HANDLER_ERROR;
}
/* check the other procs if they have a lower load */
for (gw_proc *proc = hctx->proc->next; proc; proc = proc->next) {
if (proc->state != PROC_STATE_RUNNING) continue;
if (proc->load < hctx->proc->load) hctx->proc = proc;
}
gw_proc_load_inc(hctx->host, hctx->proc);
hctx->fd = fdevent_socket_nb_cloexec(hctx->host->family,SOCK_STREAM,0);
if (-1 == hctx->fd) {
log_error_st * const errh = r->conf.errh;
if (errno == EMFILE || errno == EINTR) {
log_error(errh, __FILE__, __LINE__,
"wait for fd at connection: %d", r->con->fd);
return HANDLER_WAIT_FOR_FD;
}
log_perror(errh, __FILE__, __LINE__,
"socket failed %d %d",r->con->srv->cur_fds,r->con->srv->max_fds);
return HANDLER_ERROR;
}
++r->con->srv->cur_fds;
hctx->fdn = fdevent_register(hctx->ev,hctx->fd,gw_handle_fdevent,hctx);
if (hctx->proc->is_local) {
hctx->pid = hctx->proc->pid;
}
switch (gw_establish_connection(r, hctx->host, hctx->proc, hctx->pid,
hctx->fd, hctx->conf.debug)) {
case 1: /* connection is in progress */
fdevent_fdnode_event_set(hctx->ev, hctx->fdn, FDEVENT_OUT);
gw_set_state(hctx, GW_STATE_CONNECT_DELAYED);
return HANDLER_WAIT_FOR_EVENT;
case -1:/* connection error */
return HANDLER_ERROR;
case 0: /* everything is ok, go on */
hctx->reconnects = 0;
break;
}
__attribute_fallthrough__
case GW_STATE_CONNECT_DELAYED:
if (hctx->state == GW_STATE_CONNECT_DELAYED) { /*(not GW_STATE_INIT)*/
int socket_error = fdevent_connect_status(hctx->fd);
if (socket_error != 0) {
errno = socket_error; /*(for log_perror())*/
gw_proc_connect_error(r, hctx->host, hctx->proc, hctx->pid,
socket_error, hctx->conf.debug);
return HANDLER_ERROR;
}
/* go on with preparing the request */
}
gw_proc_connect_success(hctx->host, hctx->proc, hctx->conf.debug, r);
gw_set_state(hctx, GW_STATE_PREPARE_WRITE);
__attribute_fallthrough__
case GW_STATE_PREPARE_WRITE:
/* ok, we have the connection */
{
handler_t rc = hctx->create_env(hctx);
if (HANDLER_GO_ON != rc) {
if (HANDLER_FINISHED != rc && HANDLER_ERROR != rc)
fdevent_fdnode_event_clr(hctx->ev, hctx->fdn, FDEVENT_OUT);
return rc;
}
}
/*(disable Nagle algorithm if streaming and content-length unknown)*/
if (AF_UNIX != hctx->host->family) {
if (r->reqbody_length < 0) {
if (-1 == fdevent_set_tcp_nodelay(hctx->fd, 1)) {
/*(error, but not critical)*/
}
}
}
fdevent_fdnode_event_add(hctx->ev, hctx->fdn, FDEVENT_IN|FDEVENT_RDHUP);
gw_set_state(hctx, GW_STATE_WRITE);
__attribute_fallthrough__
case GW_STATE_WRITE:
if (!chunkqueue_is_empty(&hctx->wb)) {
log_error_st * const errh = r->conf.errh;
#if 0
if (hctx->conf.debug > 1) {
log_error(errh, __FILE__, __LINE__, "sdsx",
"send data to backend (fd=%d), size=%zu",
hctx->fd, chunkqueue_length(&hctx->wb));
}
#endif
off_t bytes_out = hctx->wb.bytes_out;
if (r->con->srv->network_backend_write(hctx->fd, &hctx->wb,
MAX_WRITE_LIMIT, errh) < 0) {
switch(errno) {
case EPIPE:
case ENOTCONN:
case ECONNRESET:
/* the connection got dropped after accept()
* we don't care about that --
* if you accept() it, you have to handle it.
*/
log_error(errh, __FILE__, __LINE__,
"connection was dropped after accept() "
"(perhaps the gw process died), "
"write-offset: %lld socket: %s",
(long long)hctx->wb.bytes_out,
hctx->proc->connection_name->ptr);
return HANDLER_ERROR;
default:
log_perror(errh, __FILE__, __LINE__, "write failed");
return HANDLER_ERROR;
}
}
else if (hctx->wb.bytes_out > bytes_out) {
hctx->proc->last_used = log_monotonic_secs;
if (hctx->stdin_append
&& chunkqueue_length(&hctx->wb) < 65536 - 16384
&& !chunkqueue_is_empty(&r->reqbody_queue)) {
handler_t rc = hctx->stdin_append(hctx);
if (HANDLER_GO_ON != rc) return rc;
}
}
}
if (hctx->wb.bytes_out == hctx->wb_reqlen) {
fdevent_fdnode_event_clr(hctx->ev, hctx->fdn, FDEVENT_OUT);
gw_set_state(hctx, GW_STATE_READ);
} else {
off_t wblen = chunkqueue_length(&hctx->wb);
if ((hctx->wb.bytes_in < hctx->wb_reqlen || hctx->wb_reqlen < 0)
&& wblen < 65536 - 16384) {
/*(r->conf.stream_request_body & FDEVENT_STREAM_REQUEST)*/
if (!(r->conf.stream_request_body
& FDEVENT_STREAM_REQUEST_POLLIN)) {
r->conf.stream_request_body |=
FDEVENT_STREAM_REQUEST_POLLIN;
r->con->is_readable = 1; /* trigger optimistic client read */
}
}
if (0 == wblen) {
fdevent_fdnode_event_clr(hctx->ev, hctx->fdn, FDEVENT_OUT);
} else {
fdevent_fdnode_event_add(hctx->ev, hctx->fdn, FDEVENT_OUT);
}
}
if (r->conf.stream_request_body
& FDEVENT_STREAM_REQUEST_TCP_FIN)
gw_conditional_tcp_fin(hctx, r);
return HANDLER_WAIT_FOR_EVENT;
case GW_STATE_READ:
/* waiting for a response */
return HANDLER_WAIT_FOR_EVENT;
default:
log_error(r->conf.errh, __FILE__, __LINE__,
"(debug) unknown state");
return HANDLER_ERROR;
}
}
__attribute_cold__
static handler_t gw_write_error(gw_handler_ctx * const hctx, request_st * const r) {
int status = r->http_status;
if (hctx->state == GW_STATE_INIT ||
hctx->state == GW_STATE_CONNECT_DELAYED) {
/* (optimization to detect backend process exit while processing a
* large number of ready events; (this block could be removed)) */
server * const srv = r->con->srv;
if (0 == srv->srvconf.max_worker)
gw_restart_dead_procs(hctx->host, srv->errh, hctx->conf.debug, 0);
/* cleanup this request and let request handler start request again */
if (hctx->reconnects++ < 5) return gw_reconnect(hctx, r);
}
if (hctx->backend_error) hctx->backend_error(hctx);
gw_connection_close(hctx, r);
r->http_status = (status == 400) ? 400 : 503;
return HANDLER_FINISHED;
}
static handler_t gw_send_request(gw_handler_ctx * const hctx, request_st * const r) {
handler_t rc = gw_write_request(hctx, r);
return (HANDLER_ERROR != rc) ? rc : gw_write_error(hctx, r);
}
static handler_t gw_recv_response(gw_handler_ctx *hctx, request_st *r);
handler_t gw_handle_subrequest(request_st * const r, void *p_d) {
gw_plugin_data *p = p_d;
gw_handler_ctx *hctx = r->plugin_ctx[p->id];
if (NULL == hctx) return HANDLER_GO_ON;
if ((r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN)
&& r->resp_body_started) {
if (chunkqueue_length(&r->write_queue) > 65536 - 4096) {
/* Note: if apps inheriting gw_handle use hctx->rb, then those apps
* are responsible for limiting amount of data buffered in memory
* in hctx->rb. Currently, mod_fastcgi is the only core app doing
* so, and the maximum FCGI_Record size is 8 + 65535 + 255 = 65798
* (FCGI_HEADER_LEN(8)+contentLength(65535)+paddingLength(255)) */
fdevent_fdnode_event_clr(hctx->ev, hctx->fdn, FDEVENT_IN);
}
else if (!(fdevent_fdnode_interest(hctx->fdn) & FDEVENT_IN)) {
/* optimistic read from backend */
handler_t rc;
rc = gw_recv_response(hctx, r); /*(might invalidate hctx)*/
if (rc != HANDLER_GO_ON) return rc; /*(unless HANDLER_GO_ON)*/
fdevent_fdnode_event_add(hctx->ev, hctx->fdn, FDEVENT_IN);
}
}
/* (do not receive request body before GW_AUTHORIZER has run or else
* the request body is discarded with handler_ctx_clear() after running
* the FastCGI Authorizer) */
if (hctx->gw_mode != GW_AUTHORIZER
&& (0 == hctx->wb.bytes_in
? (r->state == CON_STATE_READ_POST || -1 == hctx->wb_reqlen)
: (hctx->wb.bytes_in < hctx->wb_reqlen || hctx->wb_reqlen < 0))) {
/* leave excess data in r->reqbody_queue, which is
* buffered to disk if too large and backend can not keep up */
/*(64k - 4k to attempt to avoid temporary files
* in conjunction with FDEVENT_STREAM_REQUEST_BUFMIN)*/
if (chunkqueue_length(&hctx->wb) > 65536 - 4096) {
if (r->conf.stream_request_body & FDEVENT_STREAM_REQUEST_BUFMIN) {
r->conf.stream_request_body &= ~FDEVENT_STREAM_REQUEST_POLLIN;
}
if (0 != hctx->wb.bytes_in) return HANDLER_WAIT_FOR_EVENT;
}
else {
handler_t rc = r->con->reqbody_read(r);
/* XXX: create configurable flag */
/* CGI environment requires that Content-Length be set.
* Send 411 Length Required if Content-Length missing.
* (occurs here if client sends Transfer-Encoding: chunked
* and module is flagged to stream request body to backend) */
if (-1 == r->reqbody_length && hctx->opts.backend != BACKEND_PROXY){
return (r->conf.stream_request_body & FDEVENT_STREAM_REQUEST)
? http_response_reqbody_read_error(r, 411)
: HANDLER_WAIT_FOR_EVENT;
}
if (hctx->wb_reqlen < -1 && r->reqbody_length >= 0) {
/* (completed receiving Transfer-Encoding: chunked) */
hctx->wb_reqlen = -hctx->wb_reqlen;
if (hctx->stdin_append) {
handler_t rca = hctx->stdin_append(hctx);
if (HANDLER_GO_ON != rca) return rca;
}
}
if ((0 != hctx->wb.bytes_in || -1 == hctx->wb_reqlen)
&& !chunkqueue_is_empty(&r->reqbody_queue)) {
if (hctx->stdin_append) {
if (chunkqueue_length(&hctx->wb) < 65536 - 16384) {
handler_t rca = hctx->stdin_append(hctx);
if (HANDLER_GO_ON != rca) return rca;
}
}
else
chunkqueue_append_chunkqueue(&hctx->wb, &r->reqbody_queue);
if (fdevent_fdnode_interest(hctx->fdn) & FDEVENT_OUT) {
return (rc == HANDLER_GO_ON) ? HANDLER_WAIT_FOR_EVENT : rc;
}
}
if (rc != HANDLER_GO_ON) return rc;
}
}
{
handler_t rc =((0==hctx->wb.bytes_in || !chunkqueue_is_empty(&hctx->wb))
&& hctx->state != GW_STATE_CONNECT_DELAYED)
? gw_send_request(hctx, r)
: HANDLER_WAIT_FOR_EVENT;
if (HANDLER_WAIT_FOR_EVENT != rc) return rc;
}
if (r->conf.stream_request_body & FDEVENT_STREAM_REQUEST_TCP_FIN)
gw_conditional_tcp_fin(hctx, r);
return HANDLER_WAIT_FOR_EVENT;
}
__attribute_cold__
static handler_t gw_recv_response_error(gw_handler_ctx * const hctx, request_st * const r, gw_proc * const proc);
static handler_t gw_recv_response(gw_handler_ctx * const hctx, request_st * const r) {
/*(XXX: make this a configurable flag for other protocols)*/
buffer *b = (hctx->opts.backend == BACKEND_FASTCGI
|| hctx->opts.backend == BACKEND_AJP13)
? chunk_buffer_acquire()
: hctx->response;
const off_t bytes_in = r->write_queue.bytes_in;
handler_t rc = http_response_read(r, &hctx->opts, b, hctx->fdn);
if (b != hctx->response) chunk_buffer_release(b);
gw_proc * const proc = hctx->proc;
switch (rc) {
default:
/* change in r->write_queue.bytes_in used to approximate backend read,
* since bytes read from backend, if any, might be consumed from b by
* hctx->opts->parse callback, hampering detection here. However, this
* may not be triggered for partial collection of HTTP response headers
* or partial packets for backend protocol (e.g. FastCGI) */
if (r->write_queue.bytes_in > bytes_in)
proc->last_used = log_monotonic_secs;
return HANDLER_GO_ON;
case HANDLER_FINISHED:
proc->last_used = log_monotonic_secs;
if (hctx->gw_mode == GW_AUTHORIZER
&& (200 == r->http_status || 0 == r->http_status)) {
/*
* If we are here in AUTHORIZER mode then a request for authorizer
* was processed already, and status 200 has been returned. We need
* now to handle authorized request.
*/
char *physpath = NULL;
gw_host * const host = hctx->host;
if (host->docroot) {
buffer_copy_buffer(&r->physical.doc_root, host->docroot);
buffer_copy_buffer(&r->physical.basedir, host->docroot);
buffer_copy_path_len2(&r->physical.path,
BUF_PTR_LEN(host->docroot),
BUF_PTR_LEN(&r->uri.path));
physpath = r->physical.path.ptr;
}
gw_backend_close(hctx, r);
handler_ctx_clear(hctx);
/* don't do more than 6 loops here; normally shouldn't happen */
if (++r->loops_per_request > 5) {
log_error(r->conf.errh, __FILE__, __LINE__,
"too many loops while processing request: %s",
r->target_orig.ptr);