#include "secnet.h"
#include "util.h"
#include "netlink.h"
+#include "process.h"
#include <stdio.h>
#include <string.h>
#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
#define SLIP_END 192
#define SLIP_ESC 219
#define SLIP_ESCEND 220
#define SLIP_ESCESC 221
+struct slip {
+ struct netlink nl;
+ struct buffer_if *buff; /* We unstuff received packets into here
+ and send them to the netlink code. */
+ bool_t pending_esc;
+ netlink_deliver_fn *netlink_to_tunnel;
+ uint32_t local_address;
+};
+
+/* Generic SLIP mangling code */
+
+static void slip_stuff(struct slip *st, struct buffer_if *buf, int fd)
+{
+ uint8_t txbuf[DEFAULT_BUFSIZE];
+ uint8_t *i;
+ uint32_t j=0;
+
+ BUF_ASSERT_USED(buf);
+
+ /* XXX crunchy bytestuff code */
+ txbuf[j++]=SLIP_END;
+ for (i=buf->start; i<(buf->start+buf->size); i++) {
+ switch (*i) {
+ case SLIP_END:
+ txbuf[j++]=SLIP_ESC;
+ txbuf[j++]=SLIP_ESCEND;
+ break;
+ case SLIP_ESC:
+ txbuf[j++]=SLIP_ESC;
+ txbuf[j++]=SLIP_ESCESC;
+ break;
+ default:
+ txbuf[j++]=*i;
+ break;
+ }
+ if ((j+2)>DEFAULT_BUFSIZE) {
+ if (write(fd,txbuf,j)<0) {
+ fatal_perror("slip_stuff: write()");
+ }
+ j=0;
+ }
+ }
+ txbuf[j++]=SLIP_END;
+ if (write(fd,txbuf,j)<0) {
+ fatal_perror("slip_stuff: write()");
+ }
+ BUF_FREE(buf);
+}
+
+static void slip_unstuff(struct slip *st, uint8_t *buf, uint32_t l)
+{
+ uint32_t i;
+
+ /* XXX really crude unstuff code */
+ /* XXX check for buffer overflow */
+ BUF_ASSERT_USED(st->buff);
+ for (i=0; i<l; i++) {
+ if (st->pending_esc) {
+ st->pending_esc=False;
+ switch(buf[i]) {
+ case SLIP_ESCEND:
+ *(uint8_t *)buf_append(st->buff,1)=SLIP_END;
+ break;
+ case SLIP_ESCESC:
+ *(uint8_t *)buf_append(st->buff,1)=SLIP_ESC;
+ break;
+ default:
+ fatal("userv_afterpoll: bad SLIP escape character\n");
+ }
+ } else {
+ switch (buf[i]) {
+ case SLIP_END:
+ if (st->buff->size>0) {
+ st->netlink_to_tunnel(&st->nl,st->buff);
+ BUF_ALLOC(st->buff,"userv_afterpoll");
+ }
+ buffer_init(st->buff,st->nl.max_start_pad);
+ break;
+ case SLIP_ESC:
+ st->pending_esc=True;
+ break;
+ default:
+ *(uint8_t *)buf_append(st->buff,1)=buf[i];
+ break;
+ }
+ }
+ }
+}
+
+static void slip_init(struct slip *st, struct cloc loc, dict_t *dict,
+ string_t name, netlink_deliver_fn *to_host)
+{
+ st->netlink_to_tunnel=
+ netlink_init(&st->nl,st,loc,dict,
+ "netlink-userv-ipif",NULL,to_host);
+ st->buff=find_cl_if(dict,"buffer",CL_BUFFER,True,"name",loc);
+ st->local_address=string_item_to_ipaddr(
+ dict_find_item(dict,"local-address", True, name, loc),"netlink");
+ BUF_ALLOC(st->buff,"slip_init");
+ st->pending_esc=False;
+}
+
/* Connection to the kernel through userv-ipif */
struct userv {
- struct netlink nl;
+ struct slip slip;
int txfd; /* We transmit to userv */
int rxfd; /* We receive from userv */
string_t userv_path;
string_t service_user;
string_t service_name;
- uint32_t txbuflen;
- struct buffer_if *buff; /* We unstuff received packets into here
- and send them to the site code. */
- bool_t pending_esc;
- netlink_deliver_fn *netlink_to_tunnel;
- uint32_t local_address; /* host interface address */
+ pid_t pid;
+ bool_t expecting_userv_exit;
};
static int userv_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
uint64_t *now)
{
struct userv *st=sst;
- *nfds_io=2;
- fds[0].fd=st->txfd;
- fds[0].events=POLLERR; /* Might want to pick up POLLOUT sometime */
- fds[1].fd=st->rxfd;
- fds[1].events=POLLIN|POLLERR|POLLHUP;
+
+ if (st->rxfd!=-1) {
+ *nfds_io=2;
+ fds[0].fd=st->txfd;
+ fds[0].events=POLLERR; /* Might want to pick up POLLOUT sometime */
+ fds[1].fd=st->rxfd;
+ fds[1].events=POLLIN|POLLERR|POLLHUP;
+ } else {
+ *nfds_io=0;
+ }
return 0;
}
{
struct userv *st=sst;
uint8_t rxbuf[DEFAULT_BUFSIZE];
- int l,i;
+ int l;
+
+ if (nfds==0) return;
if (fds[1].revents&POLLERR) {
- Message(M_ERROR,"%s: userv_afterpoll: hup!\n",st->nl.name);
+ Message(M_ERR,"%s: userv_afterpoll: POLLERR!\n",st->slip.nl.name);
}
if (fds[1].revents&POLLIN) {
l=read(st->rxfd,rxbuf,DEFAULT_BUFSIZE);
if (l<0) {
- fatal_perror("%s: userv_afterpoll: read(rxfd)",st->nl.name);
- }
- if (l==0) {
+ if (errno!=EINTR)
+ fatal_perror("%s: userv_afterpoll: read(rxfd)",
+ st->slip.nl.name);
+ } else if (l==0) {
fatal("%s: userv_afterpoll: read(rxfd)=0; userv gone away?\n",
- st->nl.name);
- }
- /* XXX really crude unstuff code */
- /* XXX check for buffer overflow */
- BUF_ASSERT_USED(st->buff);
- for (i=0; i<l; i++) {
- if (st->pending_esc) {
- st->pending_esc=False;
- switch(rxbuf[i]) {
- case SLIP_ESCEND:
- *(uint8_t *)buf_append(st->buff,1)=SLIP_END;
- break;
- case SLIP_ESCESC:
- *(uint8_t *)buf_append(st->buff,1)=SLIP_ESC;
- break;
- default:
- fatal("userv_afterpoll: bad SLIP escape character\n");
- }
- } else {
- switch (rxbuf[i]) {
- case SLIP_END:
- if (st->buff->size>0) {
- st->netlink_to_tunnel(&st->nl,NULL,
- st->buff);
- BUF_ALLOC(st->buff,"userv_afterpoll");
- }
- buffer_init(st->buff,st->nl.max_start_pad);
- break;
- case SLIP_ESC:
- st->pending_esc=True;
- break;
- default:
- *(uint8_t *)buf_append(st->buff,1)=rxbuf[i];
- break;
- }
- }
- }
+ st->slip.nl.name);
+ } else slip_unstuff(&st->slip,rxbuf,l);
}
}
/* Send buf to the kernel. Free buf before returning. */
-static void userv_deliver_to_kernel(void *sst, void *cid,
- struct buffer_if *buf)
+static void userv_deliver_to_kernel(void *sst, struct buffer_if *buf)
{
struct userv *st=sst;
- uint8_t txbuf[DEFAULT_BUFSIZE];
- uint8_t *i;
- uint32_t j;
- BUF_ASSERT_USED(buf);
+ slip_stuff(&st->slip,buf,st->txfd);
+}
- /* Spit the packet at userv-ipif: SLIP start marker, then
- bytestuff the packet, then SLIP end marker */
- /* XXX crunchy bytestuff code */
- j=0;
- txbuf[j++]=SLIP_END;
- for (i=buf->start; i<(buf->start+buf->size); i++) {
- switch (*i) {
- case SLIP_END:
- txbuf[j++]=SLIP_ESC;
- txbuf[j++]=SLIP_ESCEND;
- break;
- case SLIP_ESC:
- txbuf[j++]=SLIP_ESC;
- txbuf[j++]=SLIP_ESCESC;
- break;
- default:
- txbuf[j++]=*i;
- break;
- }
+static void userv_userv_callback(void *sst, pid_t pid, int status)
+{
+ struct userv *st=sst;
+
+ if (pid!=st->pid) {
+ Message(M_WARNING,"userv_callback called unexpectedly with pid %d "
+ "(expected %d)\n",pid,st->pid);
+ return;
}
- txbuf[j++]=SLIP_END;
- if (write(st->txfd,txbuf,j)<0) {
- fatal_perror("userv_deliver_to_kernel: write()");
+ if (!st->expecting_userv_exit) {
+ if (WIFEXITED(status)) {
+ fatal("%s: userv exited unexpectedly with status %d\n",
+ st->slip.nl.name,WEXITSTATUS(status));
+ } else if (WIFSIGNALED(status)) {
+ fatal("%s: userv exited unexpectedly: uncaught signal %d\n",
+ st->slip.nl.name,WTERMSIG(status));
+ } else {
+ fatal("%s: userv stopped unexpectedly\n");
+ }
}
- BUF_FREE(buf);
+ Message(M_WARNING,"%s: userv subprocess died with status %d\n",
+ st->slip.nl.name,WEXITSTATUS(status));
+ st->pid=0;
}
-static void userv_phase_hook(void *sst, uint32_t newphase)
+struct userv_entry_rec {
+ string_t path;
+ char **argv;
+ int in;
+ int out;
+ /* XXX perhaps we should collect and log stderr? */
+};
+
+static void userv_entry(void *sst)
{
- struct userv *st=sst;
- pid_t child;
+ struct userv_entry_rec *st=sst;
+
+ dup2(st->in,0);
+ dup2(st->out,1);
+
+ /* XXX close all other fds */
+ setsid();
+ execvp(st->path,st->argv);
+ perror("userv-entry: execvp()");
+ exit(1);
+}
+
+static void userv_invoke_userv(struct userv *st)
+{
+ struct userv_entry_rec *er;
int c_stdin[2];
int c_stdout[2];
string_t addrs;
string_t nets;
string_t s;
struct netlink_route *r;
+ struct ipset *isnets;
+ struct subnet_list *snets;
int i;
+ uint8_t confirm;
+
+ if (st->pid) {
+ fatal("userv_invoke_userv: already running\n");
+ }
/* This is where we actually invoke userv - all the networks we'll
be using should already have been registered. */
- addrs=safe_malloc(512,"userv_phase_hook:addrs");
- snprintf(addrs,512,"%s,%s,%d,slip",ipaddr_to_string(st->local_address),
- ipaddr_to_string(st->nl.secnet_address),st->nl.mtu);
+ addrs=safe_malloc(512,"userv_invoke_userv:addrs");
+ snprintf(addrs,512,"%s,%s,%d,slip",
+ ipaddr_to_string(st->slip.local_address),
+ ipaddr_to_string(st->slip.nl.secnet_address),st->slip.nl.mtu);
- nets=safe_malloc(1024,"userv_phase_hook:nets");
- *nets=0;
- r=st->nl.routes;
- for (i=0; i<st->nl.n_routes; i++) {
+ r=st->slip.nl.routes;
+ isnets=ipset_new();
+ for (i=0; i<st->slip.nl.n_routes; i++) {
if (r[i].up) {
+ struct ipset *sn,*nis;
r[i].kup=True;
- s=subnet_to_string(&r[i].net);
- strcat(nets,s);
- strcat(nets,",");
- free(s);
+ sn=ipset_from_subnet(r[i].net);
+ nis=ipset_union(isnets,sn);
+ ipset_free(sn);
+ ipset_free(isnets);
+ isnets=nis;
}
}
+ snets=ipset_to_subnet_list(isnets);
+ ipset_free(isnets);
+ nets=safe_malloc(20*snets->entries,"userv_invoke_userv:nets");
+ *nets=0;
+ for (i=0; i<snets->entries; i++) {
+ s=subnet_to_string(snets->list[i]);
+ strcat(nets,s);
+ strcat(nets,",");
+ free(s);
+ }
nets[strlen(nets)-1]=0;
+ subnet_list_free(snets);
- Message(M_INFO,"%s: about to invoke: %s %s %s %s %s\n",st->nl.name,
+ Message(M_INFO,"%s: about to invoke: %s %s %s %s %s\n",st->slip.nl.name,
st->userv_path,st->service_user,st->service_name,addrs,nets);
- /* Allocate buffer, plus space for padding. Make sure we end up
- with the start of the packet well-aligned. */
- /* ALIGN(st->max_start_pad,16); */
- /* ALIGN(st->max_end_pad,16); */
-
- st->pending_esc=False;
+ st->slip.pending_esc=False;
/* Invoke userv */
if (pipe(c_stdin)!=0) {
- fatal_perror("userv_phase_hook: pipe(c_stdin)");
+ fatal_perror("userv_invoke_userv: pipe(c_stdin)");
}
if (pipe(c_stdout)!=0) {
- fatal_perror("userv_phase_hook: pipe(c_stdout)");
+ fatal_perror("userv_invoke_userv: pipe(c_stdout)");
}
st->txfd=c_stdin[1];
st->rxfd=c_stdout[0];
- child=fork();
- if (child==-1) {
- fatal_perror("userv_phase_hook: fork()");
+ er=safe_malloc(sizeof(*r),"userv_invoke_userv: er");
+
+ er->in=c_stdin[0];
+ er->out=c_stdout[1];
+ /* The arguments are:
+ userv
+ service-user
+ service-name
+ local-addr,secnet-addr,mtu,protocol
+ route1,route2,... */
+ er->argv=safe_malloc(sizeof(*er->argv)*6,"userv_invoke_userv:argv");
+ er->argv[0]=st->userv_path;
+ er->argv[1]=st->service_user;
+ er->argv[2]=st->service_name;
+ er->argv[3]=addrs;
+ er->argv[4]=nets;
+ er->argv[5]=NULL;
+ er->path=st->userv_path;
+
+ st->pid=makesubproc(userv_entry, userv_userv_callback,
+ er, st, st->slip.nl.name);
+ close(er->in);
+ close(er->out);
+ free(er->argv);
+ free(er);
+ free(addrs);
+ free(nets);
+ Message(M_INFO,"%s: userv-ipif pid is %d\n",st->slip.nl.name,st->pid);
+ /* Read a single character from the pipe to confirm userv-ipif is
+ running. If we get a SIGCHLD at this point then we'll get EINTR. */
+ if (read(st->rxfd,&confirm,1)!=1) {
+ if (errno==EINTR) {
+ Message(M_WARNING,"%s: read of confirmation byte was "
+ "interrupted\n",st->slip.nl.name);
+ } else {
+ fatal_perror("%s: read() of confirmation byte",st->slip.nl.name);
+ }
+ } else {
+ if (confirm!=SLIP_END) {
+ fatal("%s: bad confirmation byte %d from userv-ipif\n",
+ st->slip.nl.name,confirm);
+ }
+ }
+ /* Mark rxfd non-blocking */
+ if (fcntl(st->rxfd, F_SETFL, fcntl(st->rxfd, F_GETFL)|O_NONBLOCK)==-1) {
+ fatal_perror("%s: fcntl(O_NONBLOCK)",st->slip.nl.name);
}
- if (child==0) {
- char **argv;
-
- /* We are the child. Modify our stdin and stdout, then exec userv */
- dup2(c_stdin[0],0);
- dup2(c_stdout[1],1);
- close(c_stdin[1]);
- close(c_stdout[0]);
-
- /* The arguments are:
- userv
- service-user
- service-name
- local-addr,secnet-addr,mtu,protocol
- route1,route2,... */
- argv=malloc(sizeof(*argv)*6);
- argv[0]=st->userv_path;
- argv[1]=st->service_user;
- argv[2]=st->service_name;
- argv[3]=addrs;
- argv[4]=nets;
- argv[5]=NULL;
- execvp(st->userv_path,argv);
- perror("netlink-userv-ipif: execvp");
-
- exit(1);
+}
+
+static void userv_kill_userv(struct userv *st)
+{
+ if (st->pid) {
+ kill(-st->pid,SIGTERM);
+ st->expecting_userv_exit=True;
+ }
+}
+
+static void userv_phase_hook(void *sst, uint32_t newphase)
+{
+ struct userv *st=sst;
+ /* We must wait until signal processing has started before forking
+ userv */
+ if (newphase==PHASE_RUN) {
+ userv_invoke_userv(st);
+ /* Register for poll() */
+ register_for_poll(st, userv_beforepoll, userv_afterpoll, 2,
+ st->slip.nl.name);
+ }
+ if (newphase==PHASE_SHUTDOWN) {
+ userv_kill_userv(st);
}
- /* We are the parent... */
-
- /* Register for poll() */
- register_for_poll(st, userv_beforepoll, userv_afterpoll, 2, st->nl.name);
}
static list_t *userv_apply(closure_t *self, struct cloc loc, dict_t *context,
dict=item->data.dict;
- st->netlink_to_tunnel=
- netlink_init(&st->nl,st,loc,dict,
- "netlink-userv-ipif",NULL,userv_deliver_to_kernel);
+ slip_init(&st->slip,loc,dict,"netlink-userv-ipif",
+ userv_deliver_to_kernel);
st->userv_path=dict_read_string(dict,"userv-path",False,"userv-netlink",
loc);
if (!st->userv_path) st->userv_path="userv";
if (!st->service_user) st->service_user="root";
if (!st->service_name) st->service_name="ipif";
- st->buff=find_cl_if(dict,"buffer",CL_BUFFER,True,"userv-netlink",loc);
- st->local_address=string_to_ipaddr(
- dict_find_item(dict,"local-address", True, "netlink", loc),"netlink");
- BUF_ALLOC(st->buff,"netlink:userv_apply");
-
st->rxfd=-1; st->txfd=-1;
- add_hook(PHASE_DROPPRIV,userv_phase_hook,st);
+ st->pid=0;
+ st->expecting_userv_exit=False;
+ add_hook(PHASE_RUN,userv_phase_hook,st);
+ add_hook(PHASE_SHUTDOWN,userv_phase_hook,st);
- return new_closure(&st->nl.cl);
+ return new_closure(&st->slip.nl.cl);
}
init_module slip_module;