mirror of
https://github.com/pi-hole/dnsmasq.git
synced 2025-12-19 10:18:25 +00:00
Accumulated 2.60 changes going into git
This commit is contained in:
Simon Kelley
293
src/helper.c
293
src/helper.c
@@ -16,6 +16,8 @@
|
||||
|
||||
#include "dnsmasq.h"
|
||||
|
||||
#ifdef HAVE_SCRIPT
|
||||
|
||||
/* This file has code to fork a helper process which recieves data via a pipe
|
||||
shared with the main process and which is responsible for calling a script when
|
||||
DHCP leases change.
|
||||
@@ -28,11 +30,20 @@
|
||||
main process.
|
||||
*/
|
||||
|
||||
#if defined(HAVE_DHCP) && defined(HAVE_SCRIPT)
|
||||
|
||||
static void my_setenv(const char *name, const char *value, int *error);
|
||||
static unsigned char *grab_extradata(unsigned char *buf, unsigned char *end, char *env, int *err);
|
||||
|
||||
#ifdef HAVE_LUASCRIPT
|
||||
#include <lua.h>
|
||||
#include <lualib.h>
|
||||
#include <lauxlib.h>
|
||||
|
||||
lua_State *lua;
|
||||
|
||||
static unsigned char *grab_extradata_lua(unsigned char *buf, unsigned char *end, char *field);
|
||||
#endif
|
||||
|
||||
|
||||
struct script_data
|
||||
{
|
||||
unsigned char action, hwaddr_len, hwaddr_type;
|
||||
@@ -61,7 +72,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
then fork our process. */
|
||||
if (pipe(pipefd) == -1 || !fix_fd(pipefd[1]) || (pid = fork()) == -1)
|
||||
{
|
||||
send_event(err_fd, EVENT_PIPE_ERR, errno);
|
||||
send_event(err_fd, EVENT_PIPE_ERR, errno, NULL);
|
||||
_exit(0);
|
||||
}
|
||||
|
||||
@@ -88,38 +99,98 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
{
|
||||
if (option_bool(OPT_NO_FORK))
|
||||
/* send error to daemon process if no-fork */
|
||||
send_event(event_fd, EVENT_HUSER_ERR, errno);
|
||||
send_event(event_fd, EVENT_USER_ERR, errno, daemon->scriptuser);
|
||||
else
|
||||
{
|
||||
/* kill daemon */
|
||||
send_event(event_fd, EVENT_DIE, 0);
|
||||
send_event(event_fd, EVENT_DIE, 0, NULL);
|
||||
/* return error */
|
||||
send_event(err_fd, EVENT_HUSER_ERR, errno);
|
||||
send_event(err_fd, EVENT_USER_ERR, errno, daemon->scriptuser);
|
||||
}
|
||||
_exit(0);
|
||||
}
|
||||
}
|
||||
|
||||
/* close all the sockets etc, we don't need them here. This closes err_fd, so that
|
||||
main process can return. */
|
||||
/* close all the sockets etc, we don't need them here.
|
||||
Don't close err_fd, in case the lua-init fails.
|
||||
Note that we have to do this before lua init
|
||||
so we don't close any lua fds. */
|
||||
for (max_fd--; max_fd >= 0; max_fd--)
|
||||
if (max_fd != STDOUT_FILENO && max_fd != STDERR_FILENO &&
|
||||
max_fd != STDIN_FILENO && max_fd != pipefd[0] && max_fd != event_fd)
|
||||
max_fd != STDIN_FILENO && max_fd != pipefd[0] &&
|
||||
max_fd != event_fd && max_fd != err_fd)
|
||||
close(max_fd);
|
||||
|
||||
#ifdef HAVE_LUASCRIPT
|
||||
if (daemon->luascript)
|
||||
{
|
||||
const char *lua_err = NULL;
|
||||
lua = lua_open();
|
||||
luaL_openlibs(lua);
|
||||
|
||||
/* get Lua to load our script file */
|
||||
if (luaL_dofile(lua, daemon->luascript) != 0)
|
||||
lua_err = lua_tostring(lua, -1);
|
||||
else
|
||||
{
|
||||
lua_getglobal(lua, "lease");
|
||||
if (lua_type(lua, -1) != LUA_TFUNCTION)
|
||||
lua_err = _("lease() function missing in Lua script");
|
||||
}
|
||||
|
||||
if (lua_err)
|
||||
{
|
||||
if (option_bool(OPT_NO_FORK) || option_bool(OPT_DEBUG))
|
||||
/* send error to daemon process if no-fork */
|
||||
send_event(event_fd, EVENT_LUA_ERR, 0, (char *)lua_err);
|
||||
else
|
||||
{
|
||||
/* kill daemon */
|
||||
send_event(event_fd, EVENT_DIE, 0, NULL);
|
||||
/* return error */
|
||||
send_event(err_fd, EVENT_LUA_ERR, 0, (char *)lua_err);
|
||||
}
|
||||
_exit(0);
|
||||
}
|
||||
|
||||
lua_pop(lua, 1); /* remove nil from stack */
|
||||
lua_getglobal(lua, "init");
|
||||
if (lua_type(lua, -1) == LUA_TFUNCTION)
|
||||
lua_call(lua, 0, 0);
|
||||
else
|
||||
lua_pop(lua, 1); /* remove nil from stack */
|
||||
}
|
||||
#endif
|
||||
|
||||
/* All init done, close our copy of the error pipe, so that main process can return */
|
||||
if (err_fd != -1)
|
||||
close(err_fd);
|
||||
|
||||
/* loop here */
|
||||
while(1)
|
||||
{
|
||||
struct script_data data;
|
||||
char *p, *action_str, *hostname = NULL;
|
||||
char *p, *action_str, *hostname = NULL, *domain = NULL;
|
||||
unsigned char *buf = (unsigned char *)daemon->namebuff;
|
||||
unsigned char *end, *alloc_buff = NULL;
|
||||
unsigned char *end, *extradata, *alloc_buff = NULL;
|
||||
int err = 0;
|
||||
|
||||
free(alloc_buff);
|
||||
|
||||
/* we read zero bytes when pipe closed: this is our signal to exit */
|
||||
if (!read_write(pipefd[0], (unsigned char *)&data, sizeof(data), 1))
|
||||
_exit(0);
|
||||
|
||||
{
|
||||
#ifdef HAVE_LUASCRIPT
|
||||
if (daemon->luascript)
|
||||
{
|
||||
lua_getglobal(lua, "shutdown");
|
||||
if (lua_type(lua, -1) == LUA_TFUNCTION)
|
||||
lua_call(lua, 0, 0);
|
||||
}
|
||||
#endif
|
||||
_exit(0);
|
||||
}
|
||||
|
||||
if (data.action == ACTION_DEL)
|
||||
action_str = "del";
|
||||
else if (data.action == ACTION_ADD)
|
||||
@@ -139,42 +210,142 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
if (i != data.hwaddr_len - 1)
|
||||
p += sprintf(p, ":");
|
||||
}
|
||||
|
||||
/* and CLID into packet, avoid overwrite from bad data */
|
||||
if ((data.clid_len > daemon->packet_buff_sz) || !read_write(pipefd[0], buf, data.clid_len, 1))
|
||||
|
||||
/* expiry or length into dhcp_buff2 */
|
||||
#ifdef HAVE_BROKEN_RTC
|
||||
sprintf(daemon->dhcp_buff2, "%u", data.length);
|
||||
#else
|
||||
sprintf(daemon->dhcp_buff2, "%lu", (unsigned long)data.expires);
|
||||
#endif
|
||||
|
||||
/* supplied data may just exceed normal buffer (unlikely) */
|
||||
if ((data.hostname_len + data.ed_len + data.clid_len) > MAXDNAME &&
|
||||
!(alloc_buff = buf = malloc(data.hostname_len + data.ed_len + data.clid_len)))
|
||||
continue;
|
||||
|
||||
if (!read_write(pipefd[0], buf,
|
||||
data.hostname_len + data.ed_len + data.clid_len, 1))
|
||||
continue;
|
||||
|
||||
/* CLID into packet */
|
||||
for (p = daemon->packet, i = 0; i < data.clid_len; i++)
|
||||
{
|
||||
p += sprintf(p, "%.2x", buf[i]);
|
||||
if (i != data.clid_len - 1)
|
||||
p += sprintf(p, ":");
|
||||
}
|
||||
|
||||
/* and expiry or length into dhcp_buff2 */
|
||||
#ifdef HAVE_BROKEN_RTC
|
||||
sprintf(daemon->dhcp_buff2, "%u", data.length);
|
||||
|
||||
buf += data.clid_len;
|
||||
|
||||
if (data.hostname_len != 0)
|
||||
{
|
||||
char *dot;
|
||||
hostname = (char *)buf;
|
||||
hostname[data.hostname_len - 1] = 0;
|
||||
if (!legal_hostname(hostname))
|
||||
hostname = NULL;
|
||||
else if ((dot = strchr(hostname, '.')))
|
||||
{
|
||||
domain = dot+1;
|
||||
*dot = 0;
|
||||
}
|
||||
}
|
||||
|
||||
extradata = buf + data.hostname_len;
|
||||
|
||||
#ifdef HAVE_LUASCRIPT
|
||||
if (daemon->luascript)
|
||||
{
|
||||
lua_getglobal(lua, "lease"); /* function to call */
|
||||
lua_pushstring(lua, action_str); /* arg1 - action */
|
||||
lua_newtable(lua); /* arg2 - data table */
|
||||
|
||||
if (data.clid_len != 0)
|
||||
{
|
||||
lua_pushstring(lua, daemon->packet);
|
||||
lua_setfield(lua, -2, "client_id");
|
||||
}
|
||||
|
||||
if (strlen(data.interface) != 0)
|
||||
{
|
||||
lua_pushstring(lua, data.interface);
|
||||
lua_setfield(lua, -2, "interface");
|
||||
}
|
||||
|
||||
#ifdef HAVE_BROKEN_RTC
|
||||
lua_pushnumber(lua, data.length);
|
||||
lua_setfield(lua, -2, "lease_length");
|
||||
#else
|
||||
sprintf(daemon->dhcp_buff2, "%lu", (unsigned long)data.expires);
|
||||
lua_pushnumber(lua, data.expires);
|
||||
lua_setfield(lua, -2, "lease_expires");
|
||||
#endif
|
||||
|
||||
if (hostname)
|
||||
{
|
||||
lua_pushstring(lua, hostname);
|
||||
lua_setfield(lua, -2, "hostname");
|
||||
}
|
||||
|
||||
if (domain)
|
||||
{
|
||||
lua_pushstring(lua, domain);
|
||||
lua_setfield(lua, -2, "domain");
|
||||
}
|
||||
|
||||
end = extradata + data.ed_len;
|
||||
buf = extradata;
|
||||
buf = grab_extradata_lua(buf, end, "vendor_class");
|
||||
buf = grab_extradata_lua(buf, end, "supplied_hostname");
|
||||
buf = grab_extradata_lua(buf, end, "cpewan_oui");
|
||||
buf = grab_extradata_lua(buf, end, "cpewan_serial");
|
||||
buf = grab_extradata_lua(buf, end, "cpewan_class");
|
||||
buf = grab_extradata_lua(buf, end, "tags");
|
||||
|
||||
/* supplied data may just exceed normal buffer (unlikely) */
|
||||
if ((data.hostname_len + data.ed_len) > daemon->packet_buff_sz &&
|
||||
!(alloc_buff = buf = malloc(data.hostname_len + data.ed_len)))
|
||||
for (i = 0; buf; i++)
|
||||
{
|
||||
sprintf(daemon->dhcp_buff2, "user_class%i", i);
|
||||
buf = grab_extradata_lua(buf, end, daemon->dhcp_buff2);
|
||||
}
|
||||
|
||||
if (data.giaddr.s_addr != 0)
|
||||
{
|
||||
lua_pushstring(lua, inet_ntoa(data.giaddr));
|
||||
lua_setfield(lua, -2, "relay_address");
|
||||
}
|
||||
|
||||
if (data.action != ACTION_DEL && data.remaining_time != 0)
|
||||
{
|
||||
lua_pushnumber(lua, data.remaining_time);
|
||||
lua_setfield(lua, -2, "time_remaining");
|
||||
}
|
||||
|
||||
if (data.action == ACTION_OLD_HOSTNAME && hostname)
|
||||
{
|
||||
lua_pushstring(lua, hostname);
|
||||
lua_setfield(lua, -2, "old_hostname");
|
||||
}
|
||||
|
||||
lua_pushstring(lua, daemon->dhcp_buff);
|
||||
lua_setfield(lua, -2, "mac_address");
|
||||
|
||||
lua_pushstring(lua, inet_ntoa(data.addr));
|
||||
lua_setfield(lua, -2, "ip_address");
|
||||
|
||||
lua_call(lua, 2, 0); /* pass 2 values, expect 0 */
|
||||
}
|
||||
#endif
|
||||
|
||||
/* no script, just lua */
|
||||
if (!daemon->lease_change_command)
|
||||
continue;
|
||||
|
||||
if (!read_write(pipefd[0], buf,
|
||||
data.hostname_len + data.ed_len, 1))
|
||||
continue;
|
||||
|
||||
|
||||
/* possible fork errors are all temporary resource problems */
|
||||
while ((pid = fork()) == -1 && (errno == EAGAIN || errno == ENOMEM))
|
||||
sleep(2);
|
||||
|
||||
free(alloc_buff);
|
||||
|
||||
if (pid == -1)
|
||||
continue;
|
||||
|
||||
|
||||
/* wait for child to complete */
|
||||
if (pid != 0)
|
||||
{
|
||||
@@ -188,9 +359,9 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
{
|
||||
/* On error send event back to main process for logging */
|
||||
if (WIFSIGNALED(status))
|
||||
send_event(event_fd, EVENT_KILLED, WTERMSIG(status));
|
||||
send_event(event_fd, EVENT_KILLED, WTERMSIG(status), NULL);
|
||||
else if (WIFEXITED(status) && WEXITSTATUS(status) != 0)
|
||||
send_event(event_fd, EVENT_EXITED, WEXITSTATUS(status));
|
||||
send_event(event_fd, EVENT_EXITED, WEXITSTATUS(status), NULL);
|
||||
break;
|
||||
}
|
||||
|
||||
@@ -213,22 +384,11 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
my_setenv("DNSMASQ_LEASE_EXPIRES", daemon->dhcp_buff2, &err);
|
||||
#endif
|
||||
|
||||
if (data.hostname_len != 0)
|
||||
{
|
||||
char *dot;
|
||||
hostname = (char *)buf;
|
||||
hostname[data.hostname_len - 1] = 0;
|
||||
if (!legal_hostname(hostname))
|
||||
hostname = NULL;
|
||||
else if ((dot = strchr(hostname, '.')))
|
||||
{
|
||||
my_setenv("DNSMASQ_DOMAIN", dot+1, &err);
|
||||
*dot = 0;
|
||||
}
|
||||
buf += data.hostname_len;
|
||||
}
|
||||
|
||||
end = buf + data.ed_len;
|
||||
if (domain)
|
||||
my_setenv("DNSMASQ_DOMAIN", domain, &err);
|
||||
|
||||
end = extradata + data.ed_len;
|
||||
buf = extradata;
|
||||
buf = grab_extradata(buf, end, "DNSMASQ_VENDOR_CLASS", &err);
|
||||
buf = grab_extradata(buf, end, "DNSMASQ_SUPPLIED_HOSTNAME", &err);
|
||||
buf = grab_extradata(buf, end, "DNSMASQ_CPEWAN_OUI", &err);
|
||||
@@ -245,7 +405,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
if (data.giaddr.s_addr != 0)
|
||||
my_setenv("DNSMASQ_RELAY_ADDRESS", inet_ntoa(data.giaddr), &err);
|
||||
|
||||
if (data.action != ACTION_DEL)
|
||||
if (data.action != ACTION_DEL && data.remaining_time != 0)
|
||||
{
|
||||
sprintf(daemon->dhcp_buff2, "%u", data.remaining_time);
|
||||
my_setenv("DNSMASQ_TIME_REMAINING", daemon->dhcp_buff2, &err);
|
||||
@@ -271,7 +431,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
|
||||
err = errno;
|
||||
}
|
||||
/* failed, send event so the main process logs the problem */
|
||||
send_event(event_fd, EVENT_EXEC_ERR, err);
|
||||
send_event(event_fd, EVENT_EXEC_ERR, err, NULL);
|
||||
_exit(0);
|
||||
}
|
||||
}
|
||||
@@ -305,6 +465,28 @@ static unsigned char *grab_extradata(unsigned char *buf, unsigned char *end, ch
|
||||
return next + 1;
|
||||
}
|
||||
|
||||
#ifdef HAVE_LUASCRIPT
|
||||
static unsigned char *grab_extradata_lua(unsigned char *buf, unsigned char *end, char *field)
|
||||
{
|
||||
unsigned char *next;
|
||||
|
||||
if (!buf || (buf == end))
|
||||
return NULL;
|
||||
|
||||
for (next = buf; *next != 0; next++)
|
||||
if (next == end)
|
||||
return NULL;
|
||||
|
||||
if (next != buf)
|
||||
{
|
||||
lua_pushstring(lua, (char *)buf);
|
||||
lua_setfield(lua, -2, field);
|
||||
}
|
||||
|
||||
return next + 1;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* pack up lease data into a buffer */
|
||||
void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t now)
|
||||
{
|
||||
@@ -358,7 +540,11 @@ void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t n
|
||||
#else
|
||||
buf->expires = lease->expires;
|
||||
#endif
|
||||
buf->remaining_time = (unsigned int)difftime(lease->expires, now);
|
||||
|
||||
if (lease->expires != 0)
|
||||
buf->remaining_time = (unsigned int)difftime(lease->expires, now);
|
||||
else
|
||||
buf->remaining_time = 0;
|
||||
|
||||
p = (unsigned char *)(buf+1);
|
||||
if (clid_len != 0)
|
||||
@@ -408,3 +594,4 @@ void helper_write(void)
|
||||
#endif
|
||||
|
||||
|
||||
|
||||
|
||||
Reference in New Issue
Block a user