X-Git-Url: https://git.distorted.org.uk/~mdw/secnet/blobdiff_plain/70ad8e2cac2bafe2fca72fe5146ac0fb3719ffc9..ce53e0ea9aad729511e8b315dcbed7122272c2a1:/polypath.c diff --git a/polypath.c b/polypath.c index ddcfeeb..a8b2759 100644 --- a/polypath.c +++ b/polypath.c @@ -1,6 +1,24 @@ /* polypath * send/receive module for secnet * for multi-route setups */ +/* + * This file is part of secnet. + * See README for full list of copyright holders. + * + * secnet 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 d of the License, or + * (at your option) any later version. + * + * secnet 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 + * version 3 along with secnet; if not, see + * https://www.gnu.org/licenses/gpl.html. + */ #include "secnet.h" #include "util.h" @@ -27,19 +45,28 @@ struct polypath { const char *const *ifname_pats; const char *const *monitor_command; bool_t permit_loopback; - LIST_HEAD(,interf) interfs; + LIST_HEAD(interf_list, interf) interfs_general; + struct interf_list interfs_dedicated; struct buffer_if lbuf; int monitor_fd; pid_t monitor_pid; + int privsep_incoming_fd; + int privsep_ipcsock_fd; +}; + +struct comm_clientinfo { + union iaddr dedicated; /* might be AF_UNSPEC */ }; +static void polypath_phase_shutdown(void *sst, uint32_t newphase); + #define LG 0, st->uc.cc.cl.description, &st->uc.cc.loc static const char *const default_loopback_ifname_pats[] = { "!lo", 0 }; static const char *const default_ifname_pats[] = { - "!tun*","!tap*","!sl*","!userv*", "*", 0 + "!tun*","!tap*","!sl*","!userv*", "@hippo*", "*", 0 }; static const char *const default_monitor_command[] = { @@ -61,7 +88,7 @@ static const char *polypath_addr_to_string(void *commst, } static bool_t ifname_search_pats(struct polypath *st, struct cloc loc, - const char *ifname, bool_t *want_io, + const char *ifname, char *want_io, const char *const *pats) { /* Returns True iff we found a list entry, in which case *want_io * is set to the sense of that entry. Otherwise *want_io is set @@ -71,9 +98,8 @@ static bool_t ifname_search_pats(struct polypath *st, struct cloc loc, const char *const *pati; for (pati=pats; *pati; pati++) { const char *pat=*pati; - if (*pat=='!') { *want_io=False; pat++; } - else if (*pat=='+') { *want_io=True; pat++; } - else if (*pat=='*' || isalnum((unsigned char)*pat)) { *want_io=True; } + if (*pat=='!' || *pat=='+' || *pat=='@') { *want_io=*pat; pat++; } + else if (*pat=='*' || isalnum((unsigned char)*pat)) { *want_io='+'; } else cfgfatal(loc,"polypath","invalid interface name pattern `%s'",pat); int match=fnmatch(pat,ifname,0); if (match==0) return True; @@ -83,13 +109,13 @@ static bool_t ifname_search_pats(struct polypath *st, struct cloc loc, return False; } -static bool_t ifname_wanted(struct polypath *st, struct cloc loc, - const char *ifname) { - bool_t want=False; /* pretend an empty cfg ends with ! */ +static char ifname_wanted(struct polypath *st, struct cloc loc, + const char *ifname) { + char want='!'; /* pretend an empty cfg ends with ! */ if (ifname_search_pats(st,loc,ifname,&want, st->ifname_pats)) return want; - if (want) /* last pattern was positive, do not search default */ - return False; + if (want!='!') /* last pattern was positive, do not search default */ + return '!'; if (!st->permit_loopback && ifname_search_pats(st,loc,ifname,&want, default_loopback_ifname_pats)) return want; @@ -98,6 +124,21 @@ static bool_t ifname_wanted(struct polypath *st, struct cloc loc, abort(); } +static struct comm_clientinfo *polypath_clientinfo(void *state, + dict_t *dict, struct cloc cloc) { + struct comm_clientinfo *clientinfo; + + NEW(clientinfo); + FILLZERO(*clientinfo); + clientinfo->dedicated.sa.sa_family=AF_UNSPEC; + + item_t *item = dict_find_item(dict,"dedicated-interface-addr", + False,"polypath",cloc); + if (item) string_item_to_iaddr(item,0,&clientinfo->dedicated, + "polypath"); + return clientinfo; +} + static int polypath_beforepoll(void *state, struct pollfd *fds, int *nfds_io, int *timeout_io) { @@ -123,14 +164,15 @@ static inline bool_t matches32(uint32_t word, uint32_t prefix, int prefixlen) * and * out: */ -#define BAD(m) do{ bad(st,badctx,m,0); goto out; }while(0) -#define BADE(m,ev) do{ bad(st,badctx,m,ev); goto out; }while(0) +#define BAD(m) do{ bad(st,badctx,M_WARNING,m,0); goto out; }while(0) +#define BADE(m,ev) do{ bad(st,badctx,M_WARNING,m,ev); goto out; }while(0) typedef void bad_fn_type(struct polypath *st, void *badctx, - const char* m, int ev); + int mclass, const char* m, int ev); typedef void polypath_ppml_callback_type(struct polypath *st, bad_fn_type *bad, void *badctx, - bool_t add, const char *ifname, const char *ifaddr, + bool_t add, char want, + const char *ifname, const char *ifaddr, const union iaddr *ia, int fd /* -1 if none yet */); struct ppml_bad_ctx { @@ -138,12 +180,13 @@ struct ppml_bad_ctx { char *undospace; }; -static void ppml_bad(struct polypath *st, void *badctx, const char *m, int ev) +static void ppml_bad(struct polypath *st, void *badctx, + int mclass, const char *m, int ev) { struct ppml_bad_ctx *bc=badctx; if (bc->undospace) *(bc->undospace)=' '; - lg_perror(LG,M_WARNING,ev, + lg_perror(LG,mclass,ev, "error processing polypath state change: %s" " (while processing `%s')", m,bc->orgl); @@ -198,8 +241,8 @@ static void polypath_process_monitor_line(struct polypath *st, char *orgl, goto out; \ }while(0) - if (!ifname_wanted(st,st->uc.cc.loc,ifname)) - DONT("unwanted interface name"); + char want=ifname_wanted(st,st->uc.cc.loc,ifname); + if (want=='!') DONT("unwanted interface name"); switch (ia.sa.sa_family) { case AF_INET6: { @@ -221,6 +264,7 @@ static void polypath_process_monitor_line(struct polypath *st, char *orgl, DONT("IPv6 address is " m) DONTMASK( 100, 0, 8, "Discard-Only (RFC6666)"); DONTMASK(2001, 0, 23, "in IETF protocol block (RFC2928)"); + DONTMASK(fc00, 0, 7, "Uniqe Local unicast (RFC4193)"); #undef DONTMASK break; } @@ -249,18 +293,20 @@ static void polypath_process_monitor_line(struct polypath *st, char *orgl, #undef DONT /* OK, process it */ - callback(st, bad,badctx, add,ifname,ifaddr,&ia,-1); + callback(st, bad,badctx, add,want, ifname,ifaddr,&ia,-1); out:; } -static void dump_pria(struct polypath *st, const char *ifname) +static void dump_pria(struct polypath *st, struct interf_list *interfs, + const char *ifname, char want) { #ifdef POLYPATH_DEBUG struct interf *interf; if (ifname) - lg_perror(LG,M_DEBUG,0, "polypath record ifaddr `%s'",ifname); - LIST_FOREACH(interf, &st->interfs, entry) { + lg_perror(LG,M_DEBUG,0, "polypath record ifaddr `%s' (%c)", + ifname, want); + LIST_FOREACH(interf, interfs, entry) { lg_perror(LG,M_DEBUG,0, " polypath interface `%s', nsocks=%d", interf->name, interf->socks.n_socks); int i; @@ -293,32 +339,41 @@ static bool_t polypath_make_socket(struct polypath *st, static void polypath_record_ifaddr(struct polypath *st, bad_fn_type *bad, void *badctx, - bool_t add, const char *ifname, + bool_t add, char want, + const char *ifname, const char *ifaddr, const union iaddr *ia, int fd) { struct udpcommon *uc=&st->uc; struct interf *interf=0; + int max_interfs; struct udpsock *us=0; - dump_pria(st,ifname); + struct interf_list *interfs; + switch (want) { + case '+': interfs=&st->interfs_general; max_interfs=st->max_interfs; break; + case '@': interfs=&st->interfs_dedicated; max_interfs=INT_MAX; + default: fatal("polypath: got bad want (%#x, %s)", want, ifname); + } + + dump_pria(st,interfs,ifname,want); int n_ifs=0; - LIST_FOREACH(interf,&st->interfs,entry) { + LIST_FOREACH(interf,interfs,entry) { if (!strcmp(interf->name,ifname)) goto found_interf; n_ifs++; } /* not found */ - if (n_ifs==st->max_interfs) BAD("too many interfaces"); + if (n_ifs==max_interfs) BAD("too many interfaces"); interf=malloc(sizeof(*interf)); if (!interf) BADE("malloc for new interface",errno); interf->name=0; interf->socks.n_socks=0; FILLZERO(interf->experienced_xmit_noaf); - LIST_INSERT_HEAD(&st->interfs,interf,entry); - udp_socks_register(&st->uc,&interf->socks); + LIST_INSERT_HEAD(interfs,interf,entry); interf->name=strdup(ifname); + udp_socks_register(&st->uc,&interf->socks,interf->name); if (!interf->name) BADE("strdup interface name",errno); found_interf: @@ -332,21 +387,24 @@ static void polypath_record_ifaddr(struct polypath *st, bool_t ok=polypath_make_socket(st,bad,badctx, us,ifname); if (!ok) goto out; } else { - FILLZERO(us->experienced); - us->fd=fd; + bool_t ok=udp_import_socket(uc,us,M_WARNING,fd); + if (!ok) goto out; fd=-1; } interf->socks.n_socks++; + lg_perror(LG,M_INFO,0,"using %s %s",ifname, + iaddr_to_string(&us->addr)); us=0; /* do not destroy this socket during `out' */ - lg_perror(LG,M_INFO,0,"using %s %s",ifname,ifaddr); } else { int i; for (i=0; isocks.n_socks; i++) - if (!memcmp(&interf->socks.socks[i].addr,ia,sizeof(*ia))) + if (iaddr_equal(&interf->socks.socks[i].addr,ia,True)) goto address_remove_found; - BAD("address to remove not found"); + bad(st,badctx,M_DEBUG,"address to remove not found",0); + goto out; address_remove_found: - lg_perror(LG,M_INFO,0,"removed %s %s",ifname,ifaddr); + lg_perror(LG,M_INFO,0,"removed %s %s",ifname, + iaddr_to_string(&interf->socks.socks[i].addr)); udp_destroy_socket(&st->uc,&interf->socks.socks[i]); interf->socks.socks[i]= interf->socks.socks[--interf->socks.n_socks]; @@ -364,25 +422,13 @@ static void polypath_record_ifaddr(struct polypath *st, free(interf); } - dump_pria(st,0); + dump_pria(st,interfs,0,0); } -static void polypath_afterpoll(void *state, struct pollfd *fds, int nfds) +static void subproc_problem(struct polypath *st, + enum async_linebuf_result alr, const char *emsg) { - struct polypath *st=state; - enum async_linebuf_result alr; - const char *emsg; int status; - - if (nfds<1) return; - - while ((alr=async_linebuf_read(fds,&st->lbuf,&emsg)) == async_linebuf_ok) - polypath_process_monitor_line(st,st->lbuf.base, - polypath_record_ifaddr); - - if (alr==async_linebuf_nothing) - return; - assert(st->monitor_pid); pid_t gotpid=waitpid(st->monitor_pid,&status,WNOHANG); @@ -398,72 +444,133 @@ static void polypath_afterpoll(void *state, struct pollfd *fds, int nfds) lg_perror(LG,M_FATAL,0,"unexpected EOF from interface monitor"); else lg_perror(LG,M_FATAL,0,"bad output from interface monitor: %s",emsg); - assert(!"not reached"); } +/* Used in non-privsep case, and in privsep child */ +static void afterpoll_monitor(struct polypath *st, struct pollfd *fd, + polypath_ppml_callback_type *callback) +{ + enum async_linebuf_result alr; + const char *emsg; + + while ((alr=async_linebuf_read(fd,&st->lbuf,&emsg)) == async_linebuf_ok) + polypath_process_monitor_line(st,st->lbuf.base,callback); + + if (alr==async_linebuf_nothing) + return; + + subproc_problem(st,alr,emsg); +} + +/* Used in non-privsep case only - glue for secnet main loop */ +static void polypath_afterpoll_monitor(void *state, struct pollfd *fds, + int nfds) +{ + struct polypath *st=state; + if (nfds<1) return; + afterpoll_monitor(st,fds,polypath_record_ifaddr); +} + /* Actual udp packet sending work */ + +static void polypath_sendmsg_interf(struct polypath *st, + struct interf *interf, + struct buffer_if *buf, + const struct comm_addr *dest, + const union iaddr *dedicated, + bool_t *allreasonable) +{ + int i; + int af=dest->ia.sa.sa_family; + bool_t wanted=False, attempted=False, reasonable=False; + + for (i=0; isocks.n_socks; i++) { + struct udpsock *us=&interf->socks.socks[i]; + if (dedicated && !iaddr_equal(dedicated, &us->addr, True)) + continue; + wanted=True; + if (af != us->addr.sa.sa_family) + continue; + attempted=True; + int r=sendto(us->fd,buf->start,buf->size, + 0,&dest->ia.sa,iaddr_socklen(&dest->ia)); + udp_sock_experienced(0,&st->uc,&interf->socks,us, + &dest->ia,af, r,errno); + if (r>=0) { + reasonable=True; + break; + } + if (!(errno==EAFNOSUPPORT || errno==ENETUNREACH)) + reasonable=True; + lg_perror(LG,M_DEBUG,errno,"%s [%s] xmit %"PRIu32" bytes to %s", + interf->name,iaddr_to_string(&us->addr), + buf->size,iaddr_to_string(&dest->ia)); + } + if (!wanted) + return; + + if (!attempted) + if (!interf->experienced_xmit_noaf[af]++) + lg_perror(LG,M_WARNING,0, + "%s has no suitable address to transmit %s", + interf->name, af_name(af)); + + *allreasonable *= reasonable; +} + static bool_t polypath_sendmsg(void *commst, struct buffer_if *buf, - const struct comm_addr *dest) + const struct comm_addr *dest, + struct comm_clientinfo *clientinfo) { struct polypath *st=commst; struct interf *interf; bool_t allreasonable=True; - int af=dest->ia.sa.sa_family; - LIST_FOREACH(interf,&st->interfs,entry) { - int i; - bool_t attempted=False, reasonable=False; - for (i=0; isocks.n_socks; i++) { - struct udpsock *us=&interf->socks.socks[i]; - if (af != us->addr.sa.sa_family) - continue; - attempted=True; - int r=sendto(us->fd,buf->start,buf->size, - 0,&dest->ia.sa,iaddr_socklen(&dest->ia)); - udp_sock_experienced(0,&st->uc, interf->name,us, - 1,af, r,errno); - if (r>=0) { - reasonable=True; - break; - } - if (!(errno==EAFNOSUPPORT || errno==ENETUNREACH)) - reasonable=True; - lg_perror(LG,M_DEBUG,errno,"%s [%s] xmit %"PRIu32" bytes to %s", - interf->name,iaddr_to_string(&us->addr), - buf->size,iaddr_to_string(&dest->ia)); + LIST_FOREACH(interf,&st->interfs_general,entry) { + polypath_sendmsg_interf(st,interf,buf,dest, + 0, &allreasonable); + } + if (clientinfo && clientinfo->dedicated.sa.sa_family != AF_UNSPEC) { + LIST_FOREACH(interf,&st->interfs_dedicated,entry) { + polypath_sendmsg_interf(st,interf,buf,dest, + &clientinfo->dedicated, &allreasonable); } - if (!attempted) - if (!interf->experienced_xmit_noaf[af]++) - lg_perror(LG,M_WARNING,0, - "%s has no suitable address to transmit %s", - interf->name, af_name(af)); - allreasonable *= reasonable; } return allreasonable; } -static void polypath_phase_startmonitor(void *sst, uint32_t newphase) +/* Non-privsep: called in (sole) child. Privsep: in grandchild. */ +static void child_monitor(struct polypath *st, int childfd) +{ + dup2(childfd,1); + execvp(st->monitor_command[0],(char**)st->monitor_command); + fprintf(stderr,"secnet: cannot execute %s: %s\n", + st->monitor_command[0], strerror(errno)); + exit(-1); +} + +/* General utility function. */ +static void start_subproc(struct polypath *st, void (*make_fdpair)(int[2]), + void (*child)(struct polypath *st, int childfd), + const char *desc) { - struct polypath *st=sst; int pfds[2]; assert(!st->monitor_pid); assert(st->monitor_fd<0); - pipe_cloexec(pfds); + make_fdpair(pfds); pid_t pid=fork(); if (!pid) { afterfork(); - dup2(pfds[1],1); - execvp(st->monitor_command[0],(char**)st->monitor_command); - fprintf(stderr,"secnet: cannot execute %s: %s\n", - st->monitor_command[0], strerror(errno)); - exit(-1); + close(pfds[0]); + child(st,pfds[1]); + abort(); } if (pid<0) - fatal_perror("%s: failed to fork for interface monitor", + fatal_perror("%s: failed to fork for interface monitoring", st->uc.cc.cl.description); close(pfds[1]); @@ -471,7 +578,282 @@ static void polypath_phase_startmonitor(void *sst, uint32_t newphase) st->monitor_fd=pfds[0]; setnonblock(st->monitor_fd); - register_for_poll(st,polypath_beforepoll,polypath_afterpoll,"polypath"); + lg_perror(LG,M_NOTICE,0, "%s: spawning %s [pid %ld]", + st->uc.cc.cl.description, desc, (long)st->monitor_pid); +} + +/* Non-privsep only: glue for forking the monitor, from the main loop */ +static void polypath_phase_startmonitor(void *sst, uint32_t newphase) +{ + struct polypath *st=sst; + start_subproc(st,pipe_cloexec,child_monitor, + "interface monitor (no privsep)"); + register_for_poll(st,polypath_beforepoll, + polypath_afterpoll_monitor,"polypath"); +} + +/*----- Privsep-only: -----*/ + +/* + * We use two subprocesses, a child and a grandchild. These are + * forked before secnet drops privilege. + * + * The grandchild is the same interface monitor helper script as used + * in the non-privsep case. But its lines are read by the child + * instead of by the main secnet. The child is responsible for + * creating the actual socket (binding it, etc.). Each socket is + * passed to secnet proper via fd passing, along with a data message + * describing the interface name and address. The child does not + * retain a list of current interfaces and addresses - it trusts the + * interface monitor to get that right. secnet proper still maintains + * that data structure. + * + * The result is that much of the non-privsep code can be reused, but + * just plumbed together differently. + * + * The child does not retain the socket after passing it on. + * Interface removals are handled similarly but without any fd. + * + * The result is that the configuration's limits on which interfaces + * and ports secnet may use are enforced by the privileged child. + */ + +struct privsep_mdata { + bool_t add; + char ifname[100]; + union iaddr ia; + char want; /* `+' or `@' */ +}; + +static void papp_bad(struct polypath *st, void *badctx, + int mclass, const char *m, int ev) +{ + const struct privsep_mdata *mdata=(const void*)st->lbuf.start; + const char *addr_str=badctx; + + lg_perror(LG,mclass,ev, + "error processing polypath address change %s %s [%s]: %s", + mdata->add ? "+" : "-", + mdata->ifname, addr_str, m); +} + +static void polypath_afterpoll_privsep(void *state, struct pollfd *fds, + int nfds) +/* In secnet proper; receives messages from child. */ +{ + struct polypath *st=state; + + if (nfds<1) return; + + int revents=fds[0].revents; + + const char *badbit=pollbadbit(revents); + if (badbit) subproc_problem(st,async_linebuf_broken,badbit); + + if (!(revents & POLLIN)) return; + + for (;;) { + if (st->lbuf.size==sizeof(struct privsep_mdata)) { + const struct privsep_mdata *mdata=(const void*)st->lbuf.start; + if (mdata->add && st->privsep_incoming_fd<0) + fatal("polypath (privsep): got add message data but no fd"); + if (!mdata->add && st->privsep_incoming_fd>=0) + fatal("polypath (privsep): got remove message data with fd"); + if (!memchr(mdata->ifname,0,sizeof(mdata->ifname))) + fatal("polypath (privsep): got ifname with no terminating nul"); + int af=mdata->ia.sa.sa_family; + if (!(af==AF_INET6 || af==AF_INET)) + fatal("polypath (privsep): got message data but bad AF %d",af); + const char *addr_str=iaddr_to_string(&mdata->ia); + polypath_record_ifaddr(st,papp_bad,(void*)addr_str, + mdata->add,mdata->want, + mdata->ifname,addr_str, + &mdata->ia, st->privsep_incoming_fd); + st->privsep_incoming_fd=-1; + st->lbuf.size=0; + } + struct msghdr msg; + int fd; + size_t cmsgdatalen=sizeof(fd); + char cmsg_control_buf[CMSG_SPACE(cmsgdatalen)]; + struct iovec iov; + + FILLZERO(msg); + msg.msg_iov=&iov; + msg.msg_iovlen=1; + + iov.iov_base=st->lbuf.start+st->lbuf.size; + iov.iov_len=sizeof(struct privsep_mdata)-st->lbuf.size; + + if (st->privsep_incoming_fd<0) { + msg.msg_control=cmsg_control_buf; + msg.msg_controllen=sizeof(cmsg_control_buf); + } + + ssize_t got=recvmsg(st->monitor_fd,&msg,0); + if (got<0) { + if (errno==EINTR) continue; + if (iswouldblock(errno)) break; + fatal_perror("polypath (privsep): recvmsg failed"); + } + if (got==0) + subproc_problem(st,async_linebuf_eof,0); + + st->lbuf.size+=got; + + if (msg.msg_controllen) { + size_t cmsgdatalen=sizeof(st->privsep_incoming_fd); + struct cmsghdr *h=CMSG_FIRSTHDR(&msg); + if (!(st->privsep_incoming_fd==-1 && + h && + h->cmsg_level==SOL_SOCKET && + h->cmsg_type==SCM_RIGHTS && + h->cmsg_len==CMSG_LEN(cmsgdatalen) && + !CMSG_NXTHDR(&msg,h))) + subproc_problem(st,async_linebuf_broken,"bad cmsg"); + memcpy(&st->privsep_incoming_fd,CMSG_DATA(h),cmsgdatalen); + assert(st->privsep_incoming_fd>=0); + } + + } +} + +static void privsep_handle_ifaddr(struct polypath *st, + bad_fn_type *bad, void *badctx, + bool_t add, char want, + const char *ifname, + const char *ifaddr, + const union iaddr *ia, int fd_dummy) +/* In child: handles discovered wanted interfaces, making sockets + and sending them to secnet proper. */ +{ + struct msghdr msg; + struct iovec iov; + struct udpsock us={ .fd=-1 }; + size_t cmsgdatalen=sizeof(us.fd); + char cmsg_control_buf[CMSG_SPACE(cmsgdatalen)]; + + assert(fd_dummy==-1); + + struct privsep_mdata mdata; + FILLZERO(mdata); + mdata.add=add; + + size_t l=strlen(ifname); + if (l>=sizeof(mdata.ifname)) BAD("interface name too long"); + strcpy(mdata.ifname,ifname); + mdata.want=want; + + COPY_OBJ(mdata.ia,*ia); + + iov.iov_base=&mdata; + iov.iov_len =sizeof(mdata); + + FILLZERO(msg); + msg.msg_iov=&iov; + msg.msg_iovlen=1; + + if (add) { + COPY_OBJ(us.addr,*ia); + bool_t ok=polypath_make_socket(st,bad,badctx,&us,ifname); + if (!ok) goto out; + + msg.msg_control=cmsg_control_buf; + msg.msg_controllen=sizeof(cmsg_control_buf); + + struct cmsghdr *h=CMSG_FIRSTHDR(&msg); + h->cmsg_level=SOL_SOCKET; + h->cmsg_type =SCM_RIGHTS; + h->cmsg_len =CMSG_LEN(cmsgdatalen); + memcpy(CMSG_DATA(h),&us.fd,cmsgdatalen); + } + + while (iov.iov_len) { + ssize_t got=sendmsg(st->privsep_ipcsock_fd,&msg,0); + if (got<0) { + if (errno!=EINTR) fatal_perror("polypath privsep sendmsg"); + got=0; + } else { + assert(got>0); + assert((size_t)got<=iov.iov_len); + } + iov.iov_base=(char*)iov.iov_base+got; + iov.iov_len-=got; + msg.msg_control=0; + msg.msg_controllen=0; + } + + out: + if (us.fd>=0) close(us.fd); +} + +static void child_privsep(struct polypath *st, int ipcsockfd) +/* Privsep child main loop. */ +{ + struct pollfd fds[2]; + + enter_phase(PHASE_CHILDPERSIST); + + st->privsep_ipcsock_fd=ipcsockfd; + start_subproc(st,pipe_cloexec,child_monitor, + "interface monitor (grandchild)"); + for (;;) { + int nfds=1; + int r=polypath_beforepoll(st,fds,&nfds,0); + assert(nfds==1); + assert(!r); + + fds[1].fd=st->privsep_ipcsock_fd; + fds[1].events=POLLIN; + + r=poll(fds,ARRAY_SIZE(fds),-1); + + if (r<0) { + if (errno==EINTR) continue; + fatal_perror("polypath privsep poll"); + } + if (fds[1].revents) { + if (fds[1].revents & (POLLHUP|POLLIN)) { + polypath_phase_shutdown(st,PHASE_SHUTDOWN); + exit(0); + } + fatal("polypath privsep poll parent socket revents=%#x", + fds[1].revents); + } + if (fds[0].revents & POLLNVAL) + fatal("polypath privsep poll child socket POLLNVAL"); + afterpoll_monitor(st,fds,privsep_handle_ifaddr); + } +} + +static void privsep_socketpair(int *fd) +{ + int r=socketpair(AF_UNIX,SOCK_STREAM,0,fd); + if (r) fatal_perror("socketpair(AF_UNIX,SOCK_STREAM,,)"); + setcloexec(fd[0]); + setcloexec(fd[1]); +} + +static void polypath_phase_startprivsep(void *sst, uint32_t newphase) +{ + struct polypath *st=sst; + + if (!will_droppriv()) { + add_hook(PHASE_RUN, polypath_phase_startmonitor,st); + return; + } + + start_subproc(st,privsep_socketpair,child_privsep, + "socket generator (privsep interface handler)"); + + BUF_FREE(&st->lbuf); + buffer_destroy(&st->lbuf); + buffer_new(&st->lbuf,sizeof(struct privsep_mdata)); + BUF_ALLOC(&st->lbuf,"polypath mdata buf"); + st->privsep_incoming_fd=-1; + + register_for_poll(st,polypath_beforepoll, + polypath_afterpoll_privsep,"polypath"); } static void polypath_phase_shutdown(void *sst, uint32_t newphase) @@ -483,9 +865,22 @@ static void polypath_phase_shutdown(void *sst, uint32_t newphase) } } +static void polypath_phase_childpersist(void *sst, uint32_t newphase) +{ + struct polypath *st=sst; + struct interf *interf; + + LIST_FOREACH(interf,&st->interfs_general,entry) + udp_socks_childpersist(&st->uc,&interf->socks); + LIST_FOREACH(interf,&st->interfs_dedicated,entry) + udp_socks_childpersist(&st->uc,&interf->socks); +} + #undef BAD #undef BADE +/*----- generic closure and module setup -----*/ + static list_t *polypath_apply(closure_t *self, struct cloc loc, dict_t *context, list_t *args) { @@ -495,6 +890,8 @@ static list_t *polypath_apply(closure_t *self, struct cloc loc, COMM_APPLY_STANDARD(st,&st->uc.cc,"polypath",args); UDP_APPLY_STANDARD(st,&st->uc,"polypath"); + st->uc.cc.ops.clientinfo = polypath_clientinfo; + struct udpcommon *uc=&st->uc; struct commcommon *cc=&uc->cc; @@ -514,15 +911,18 @@ static list_t *polypath_apply(closure_t *self, struct cloc loc, st->permit_loopback=dict_read_bool(d,"permit-loopback",False, "polypath",cc->loc,False); - LIST_INIT(&st->interfs); + LIST_INIT(&st->interfs_general); + LIST_INIT(&st->interfs_dedicated); buffer_new(&st->lbuf,ADNS_ADDR2TEXT_BUFLEN+100); BUF_ALLOC(&st->lbuf,"polypath lbuf"); st->monitor_fd=-1; st->monitor_pid=0; - add_hook(PHASE_RUN, polypath_phase_startmonitor,st); + add_hook(PHASE_GETRESOURCES, polypath_phase_startprivsep,st); + add_hook(PHASE_SHUTDOWN, polypath_phase_shutdown, st); + add_hook(PHASE_CHILDPERSIST,polypath_phase_childpersist,st); return new_closure(&cc->cl); }