/* echld_dispatcher.c * epan working child API internals * Parent process routines and definitions () * * $Id$ * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * Copyright (c) 2013 by Luis Ontanon * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "echld-int.h" /** PARENT and API **/ #define MAX_PENDING_REQS 16; typedef struct _req { int reqh_id; echld_msg_cb_t cb; void* cb_data; struct timeval tv; } reqh_t; typedef struct _hdlr { int id; echld_msg_type_t type; echld_msg_cb_t cb; void* cb_data; } hdlr_t; typedef struct _echld_child { int chld_id; void* data; child_state_t state; GArray* handlers; GArray* reqs; } echld_t; struct _echld_parent { echld_t* children; echld_reader_t reader; int dispatcher_fd; int dispatcher_pid; int reqh_id; GByteArray* snd; int closing; echld_parent_encoder_t* enc; parent_decoder_t* dec; } parent = {NULL,{NULL,0,NULL,-1,NULL,0},-1,-1,1,NULL,0,NULL,NULL}; static int reqh_ids = 1; #ifdef DEBUG_PARENT static int dbg_level = DEBUG_PARENT; static void parent_dbg(int level, const char* fmt, ...) { va_list ap; char str[1024]; if (level > dbg_level) return; va_start(ap,fmt); g_vsnprintf(str,1024,fmt,ap); va_end(ap); fprintf(stderr,"ParentDebug: level=%d msg='%s'\n",level,str); fflush(stderr); } #define PARENT_DBG(attrs) parent_dbg attrs #define PARENT_SEND(BYTEARR,CHILDNUM,TYPE,R_ID) do { long st = echld_write_frame(parent.dispatcher_fd, BYTEARR, CHILDNUM, TYPE, R_ID, NULL); PARENT_DBG((1,"SEND type='%s' chld_id=%d reqh_id=%d err_msg='%s'",TY(TYPE),CHILDNUM,R_ID, ( st >= 8 ? "ok" : ((st<0)?strerror(errno):"?") ) )); } while(0) #else #define PARENT_DBG(attrs) #define PARENT_SEND(BYTEARR,CHILDNUM,TYPE,R_ID) echld_write_frame(parent.dispatcher_fd, BYTEARR, CHILDNUM, TYPE, R_ID, NULL) #endif extern void echld_set_parent_dbg_level(int lvl) { (dbg_level = lvl); if (lvl > 6) { echld_common_set_dbg(lvl,stderr,"parent"); } PARENT_DBG((0,"Debug Level Set: %d",lvl)); } #define PARENT_FATAL(attrs) parent_fatal attrs static void parent_fatal(int exit_code, const char* fmt, ...) { va_list ap; char str[1024]; va_start(ap,fmt); g_vsnprintf(str,1024,fmt,ap); va_end(ap); #ifdef DEBUG_PARENT PARENT_DBG((0,"Fatal error: exit_code=%d str=%s",exit_code,str)); #else fprintf(stderr,"Fatal error: exit_code=%d str=%s",exit_code,str); #endif kill(parent.dispatcher_pid,SIGTERM); exit(exit_code); } static void echld_cleanup(void) { // int i; PARENT_DBG((4,"echld_cleanup starting")); // for (i=0;ichld_id)); c->chld_id = -1; c->data = NULL; c->state = FREE; g_array_set_size(c->handlers,0); g_array_set_size(c->reqs,0); } void parent_reaper(int sig) { int pid; int status; if (sig != SIGCHLD) { PARENT_FATAL((3333,"Must be SIGCHLD!")); } pid = waitpid(-1, &status, WNOHANG); PARENT_DBG((2,"SIGCHLD pid=%d",pid)); if (pid == parent.dispatcher_pid) { if (! parent.closing) { /* crashed */ PARENT_FATAL((DISPATCHER_DEAD,"Dispatcher process dead")); } return; } else { /* XXX: do we care? */ return; } return; } /* will initialize epan registering protocols and taps */ void echld_initialize(echld_encoding_t enc, char* argv0, int (*main)(int, char **)) { int from_disp[2]; int to_disp[2]; PARENT_DBG((1,"Echld Starting")); if (enc != ECHLD_ENCODING_JSON) { PARENT_FATAL((UNIMPLEMENTED,"Only JSON implemented")); } if ( pipe(to_disp) ) { PARENT_FATAL((DISPATCHER_PIPE_FAILED,"Failed to open pipe to dispatcher")); } else if( pipe(from_disp) ) { PARENT_FATAL((DISPATCHER_PIPE_FAILED,"Failed to open pipe from dispatcher")); } else { int pid; int i; PARENT_DBG((3,"Pipes Opened fr[0]=%d fr[1]=%d to[0]=%d to[1]=%d",from_disp[0],from_disp[1],to_disp[0],to_disp[1])); pid = fork(); if ( pid < 0 ) { PARENT_FATAL((CANNOT_FORK,"Failed to fork() reason='%s'",strerror(errno))); } else if ( pid == 0) { #ifdef PARENT_THREADS reader_realloc_buf = child_realloc_buff; #endif /* child code */ echld_cleanup(); echld_dispatcher_start(to_disp,from_disp,argv0,main); PARENT_FATAL((SHOULD_HAVE_EXITED_BEFORE,"This shoudln't happen")); } else { /* parent code */ #ifdef PARENT_THREADS reader_realloc_buf = parent_realloc_buff; #endif /* echld_common_set_dbg(9,stderr,"parent"); */ PARENT_DBG((3,"Dispatcher forked")); echld_get_all_codecs(NULL, NULL, &parent.enc, &parent.dec); parent.children = g_new0(echld_t,ECHLD_MAX_CHILDREN); parent.snd = g_byte_array_new(); parent.dispatcher_fd = to_disp[1]; parent.dispatcher_pid = pid; echld_init_reader(&(parent.reader),from_disp[0],4096); for (i=0;ireqs->len; reqh_t* rr = (reqh_t*)c->reqs->data; for(i=0; i < imax ; i++) { if (rr[i].reqh_id == reqh_id) return i; } return -1; } static echld_state_t reqh_snd(echld_t* c, echld_msg_type_t t, GByteArray* ba, echld_msg_cb_t resp_cb, void* cb_data) { int idx; reqh_t* r; int reqh_id = reqh_ids++; if (!c) { PARENT_DBG((1,"REQH_SND: No such child")); return 1; } idx = reqh_id_idx(c,-1); if (idx < 0) { reqh_t req; idx = c->reqs->len; g_array_append_val(c->reqs,req); } r = &(((reqh_t*)c->reqs->data)[idx]); r->reqh_id = reqh_id; r->cb = resp_cb; r->cb_data = cb_data; gettimeofday(&(r->tv),NULL); PARENT_DBG((4,"reqh_add: idx='%d'",idx)); PARENT_DBG((3,"REQH_SND: type='%s' chld_id=%d reqh_id=%d",TY(t), c->chld_id,reqh_id)); PARENT_SEND(ba,c->chld_id,t,reqh_id); if (ba) g_byte_array_free(ba,TRUE); /* do we? */ return reqh_id; } extern echld_reqh_id_t echld_reqh( echld_chld_id_t child_id, echld_msg_type_t t, int usecs_timeout, enc_msg_t* ba, echld_msg_cb_t resp_cb, void* cb_data) { usecs_timeout=usecs_timeout; return reqh_snd(get_child(child_id),t,ba,resp_cb,cb_data); } /* get callback data for a live request */ extern void* echld_reqh_get_data(int child_id, int reqh_id) { echld_t* c = get_child(child_id); int idx; if (!c) return NULL; idx = reqh_id_idx(c,reqh_id); if (idx >= 0) return g_array_index(c->reqs, reqh_t, idx).cb_data; else return NULL; } /* get the callback for a live request */ extern echld_msg_cb_t echld_reqh_get_cb(int child_id, int reqh_id) { echld_t* c = get_child(child_id); int idx; if (!c) return NULL; idx = reqh_id_idx(c,reqh_id); if (idx >= 0) return g_array_index(c->reqs, reqh_t, idx).cb; else return NULL; } /* set callback data for a live request */ extern gboolean echld_reqh_set_data(int child_id, int reqh_id, void* cb_data) { echld_t* c = get_child(child_id); int idx; if (!c) return FALSE; idx = reqh_id_idx(c,reqh_id); if (idx < 0) return FALSE; g_array_index(c->reqs, reqh_t, idx).cb_data = cb_data; return TRUE; } /* get the callback for a live request */ extern gboolean echld_reqh_set_cb(int child_id, int reqh_id, echld_msg_cb_t cb){ echld_t* c = get_child(child_id); int idx; if (!c) return FALSE; idx = reqh_id_idx(c,reqh_id); if (idx < 0) return FALSE; g_array_index(c->reqs, reqh_t, idx).cb = cb; return TRUE; } /* stop receiving a live request */ extern gboolean echld_reqh_detach(int child_id, int reqh_id) { echld_t* c = get_child(child_id); int idx; if (!c) return FALSE; idx = reqh_id_idx(c,reqh_id); if (idx < 0) return FALSE; g_array_remove_index(c->reqs,idx); return TRUE; } static echld_bool_t parent_dead_child(echld_msg_type_t type, enc_msg_t* ba, void* data) { echld_t* c = (echld_t*)data; char* s; if (type != ECHLD_CHILD_DEAD) { PARENT_DBG((1, "Must Be ECHLD_CHILD_DEAD")); return 1; } if ( parent.dec->child_dead(ba,&s) ) { PARENT_DBG((1,"Dead Child[%d]: %s",c->chld_id,s)); g_free(s); } parent_child_cleanup(c); return 0; } static echld_bool_t parent_get_hello(echld_msg_type_t type, enc_msg_t* ba _U_, void* data) { echld_t* c = (echld_t*)data; switch (type) { case ECHLD_HELLO: PARENT_DBG((1,"Child[%d]: =>IDLE",c->chld_id)); c->state = IDLE; return TRUE; case ECHLD_ERROR: case ECHLD_TIMEOUT: default: return FALSE; } } int chld_cmp(const void *a, const void *b) { return ((echld_t*)b)->chld_id - ((echld_t*)a)->chld_id; } static int msgh_attach(echld_t* c, echld_msg_type_t t, echld_msg_cb_t resp_cb, void* cb_data); static int next_chld_id = 1; extern int echld_new(void* child_data) { echld_t* c = get_child(-1); if (!c) return -1; c->chld_id = (next_chld_id++); c->data = child_data; c->state = CREATING; g_byte_array_set_size(parent.snd,0); PARENT_DBG((1,"Child[%d]: =>CREATING",c->chld_id)); msgh_attach(c,ECHLD_CHILD_DEAD, parent_dead_child , c); reqh_snd(c, ECHLD_NEW_CHILD, parent.snd, parent_get_hello, c); return c->chld_id; } /* XXX these fail silently */ extern void* echld_get_data(int child_id) { echld_t* c = get_child(child_id); return c ? c->data : NULL; } extern echld_state_t echld_set_data(echld_chld_id_t chld_id, void* data) { echld_t* c = get_child(chld_id); if (c) { c->data = data; return TRUE; } return FALSE; } static int msgh_idx(echld_t* c, int msgh_id) { int i = 0; int imax = c->handlers->len; for (i=0;ihandlers->data))[i].id == msgh_id) return i; } return -1; } /* start a message handler */ static int msgh_attach(echld_t* c, echld_msg_type_t t, echld_msg_cb_t resp_cb, void* cb_data) { hdlr_t h; static int msgh_id = 1; h.id = msgh_id++; h.type = t; h.cb = resp_cb; h.cb_data = cb_data; g_array_append_val(c->handlers,h); return 0; } extern int echld_msgh(int child_id, echld_msg_type_t t, echld_msg_cb_t resp_cb, void* cb_data) { echld_t* c = get_child(child_id); if (c) return msgh_attach(c,t,resp_cb,cb_data); else return -1; } /* stop it */ static echld_state_t msgh_detach(echld_t* c, int msgh_id) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return -1; g_array_remove_index(c->handlers,idx); return 1; } extern echld_state_t echld_msgh_detach(int child_id, int msgh_id) { echld_t* c = get_child(child_id); return msgh_detach(c,msgh_id); } /* get a msgh's data */ static void* msgh_get_data(echld_t* c, int msgh_id) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return NULL; return ((hdlr_t*)(c->handlers->data))[idx].cb_data; } extern void* echld_msgh_get_data(int child_id, int msgh_id) { echld_t* c = get_child(child_id); return msgh_get_data(c,msgh_id); } /* get a msgh's cb */ static echld_msg_cb_t msgh_get_cb(echld_t* c, int msgh_id) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return NULL; return ((hdlr_t*)(c->handlers->data))[idx].cb; } extern echld_msg_cb_t echld_msgh_get_cb(int child_id, int msgh_id) { echld_t* c = get_child(child_id); return msgh_get_cb(c,msgh_id); } /* get a msgh's type */ static echld_msg_type_t msgh_get_type(echld_t* c, int msgh_id) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return EC_ACTUAL_ERROR; return ((hdlr_t*)(c->handlers->data))[idx].type; } extern echld_msg_type_t echld_msgh_get_type(int child_id, int msgh_id) { echld_t* c = get_child(child_id); return c ? msgh_get_type(c,msgh_id) : EC_ACTUAL_ERROR; } /* get it all from a msgh */ static echld_state_t msgh_get_all(echld_t* c, int msgh_id, echld_msg_type_t* t, echld_msg_cb_t* cb, void** data) { int idx = msgh_idx(c,msgh_id); hdlr_t* h; if (idx < 0) return -1; h = &(((hdlr_t*)(c->handlers->data))[idx]); if (t) *t = h->type; if (cb) *cb = h->cb; if (data) *data = h->cb_data; return 0; } extern gboolean echld_msgh_get_all(int child_id, int msgh_id, echld_msg_type_t* t, echld_msg_cb_t* cb, void** data) { echld_t* c = get_child(child_id); return c && msgh_get_all(c,msgh_id,t,cb,data); } static echld_state_t msgh_set_all(echld_t* c, int msgh_id, echld_msg_type_t t, echld_msg_cb_t cb, void* data) { int idx = msgh_idx(c,msgh_id); hdlr_t* h; if (idx < 0) return -1; h = &(((hdlr_t*)(c->handlers->data))[idx]); h->type = t; h->cb = cb; h->cb_data = data; return 0; } extern gboolean echld_msgh_set_all(int child_id, int msgh_id, echld_msg_type_t t, echld_msg_cb_t cb, void* data) { echld_t* c = get_child(child_id); return c ? msgh_set_all(c,msgh_id,t,cb,data) : FALSE; } /* set a msgh's data */ static gboolean msgh_set_data(echld_t* c, int msgh_id, void* data) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return FALSE; ((hdlr_t*)(c->handlers->data))[idx].cb_data = data; return TRUE; } extern gboolean echld_msgh_set_data(int child_id, int msgh_id, void* data){ echld_t* c = get_child(child_id); return c ? msgh_set_data(c,msgh_id,data) : FALSE; } /* set a msgh's cb */ extern gboolean msgh_set_cb(echld_t* c, int msgh_id, echld_msg_cb_t cb) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return FALSE; ((hdlr_t*)(c->handlers->data))[idx].cb = cb; return TRUE; } extern gboolean echld_msgh_set_cb(int child_id, int msgh_id, echld_msg_cb_t cb) { echld_t* c = get_child(child_id); return c ? msgh_set_cb(c,msgh_id,cb) : FALSE; } /* set a msgh's type */ static gboolean msgh_set_type(echld_t* c, int msgh_id, echld_msg_type_t t) { int idx = msgh_idx(c,msgh_id); if (idx < 0) return FALSE; ((hdlr_t*)(c->handlers->data))[idx].type = t; return TRUE; } extern gboolean echld_msgh_set_type(int child_id, int msgh_id, echld_msg_type_t t) { echld_t* c = get_child(child_id); return c ? msgh_set_type(c,msgh_id,t) : FALSE; } /* call cb(id,child_data,cb_data) for each child*/ extern void echld_foreach_child(echld_iter_cb_t cb, void* cb_data) { int i; for(i=0;ichld_id,c->data,cb_data); } } static reqh_t* get_req(echld_t* c, int reqh_id) { int idx = reqh_id_idx(c,reqh_id); if(idx < 0) return NULL; return ((reqh_t*)(c->reqs->data))+idx; } static hdlr_t* get_next_hdlr_for_type(echld_t* c, echld_msg_type_t t, int* cookie) { int imax = c->handlers->len; for (;*cookiehandlers->data))[*cookie].type == t) return &( ((hdlr_t*)(c->handlers->data))[*cookie] ) ; } return NULL; } static long parent_read_frame(guint8* b, size_t len, echld_chld_id_t chld_id, echld_msg_type_t t, echld_reqh_id_t reqh_id, void* data _U_) { echld_t* c = get_child(chld_id); GByteArray* ba = g_byte_array_new(); PARENT_DBG((1,"MSG_IN<- ch=%d t='%s' rh=%d",chld_id,TY(t),reqh_id)); g_byte_array_append(ba,b, (guint)len); if (c) { reqh_t* r = get_req(c, reqh_id); int i = 0; hdlr_t* h; gboolean go_ahead = TRUE; if (r) { /* got that reqh_id */ if (r->cb) { go_ahead = r->cb(t,ba,r->cb_data); } r->reqh_id = -1; r->cb = NULL; r->cb_data = 0; r->tv.tv_sec = 0; r->tv.tv_usec = 0; PARENT_DBG((2,"hanlded by reqh_id=%d msg='%s'",reqh_id,go_ahead?"retrying":"done")); } while(go_ahead && ( h = get_next_hdlr_for_type(c,t,&i))) { if (h->cb) go_ahead = h->cb(t,ba,h->cb_data); PARENT_DBG((2,"hanlded by t='%c' msgh_id=%d msg='%s'",h->type, h->id,go_ahead?"retrying":"done")); } } else { PARENT_DBG((1,"parent_read_frame: No such child")); } g_byte_array_free(ba,TRUE); return 1; } extern int echld_fdset(fd_set* rfds, fd_set* efds) { FD_SET(parent.reader.fd, rfds); FD_SET(parent.reader.fd, efds); FD_SET(parent.dispatcher_fd, efds); return 2; } extern int echld_fd_read(fd_set* rfds, fd_set* efds) { int r_nfds=0; if (FD_ISSET(parent.reader.fd,efds) || FD_ISSET(parent.dispatcher_fd,efds) ) { /* Handle errored dispatcher */ PARENT_DBG((1,"parent errored")); return -1; } if (FD_ISSET(parent.reader.fd,rfds)) { PARENT_DBG((1,"reading from dispatcher")); echld_read_frame(&(parent.reader),parent_read_frame,&(parent)); } return r_nfds; } extern int echld_select(int nfds _U_, fd_set* rfds, fd_set* wfds, fd_set* efds, struct timeval* timeout) { fd_set my_rfds, my_wfds, my_efds; int r_nfds; if (rfds == NULL) { rfds = &my_rfds; FD_ZERO(rfds); } if (wfds == NULL) { wfds = &my_wfds; FD_ZERO(wfds); } if (efds == NULL) { efds = &my_efds; FD_ZERO(efds); } echld_fdset(rfds,efds); PARENT_DBG((2,"Select()")); r_nfds = select(FD_SETSIZE, rfds, wfds, efds, timeout); echld_fd_read(rfds,efds); return r_nfds ; } extern echld_state_t echld_wait(struct timeval* timeout) { if ( echld_select(0, NULL, NULL, NULL, timeout) < 0) { return -1; } else { return ECHLD_OK; } }