#include "util/config_file.h"
#include <signal.h>
+/** number of reads per select for delayer */
+#define TRIES_PER_SELECT 100
+
/**
* The ring buffer
*/
size_t high;
};
+/**
+ * List of proxy fds that return replies from the server to our clients.
+ */
+struct proxy {
+ /** the fd to listen for replies from server */
+ int s;
+ /** last time this was used */
+ struct timeval lastuse;
+ /** remote address */
+ struct sockaddr_storage addr;
+ /** length of addr */
+ socklen_t addr_len;
+ /** number of queries waiting (in total) */
+ size_t numwait;
+ /** number of queries sent to server (in total) */
+ size_t numsent;
+ /** numberof answers returned to client (in total) */
+ size_t numreturn;
+ /** how many times repurposed */
+ size_t numreuse;
+ /** next in proxylist */
+ struct proxy* next;
+};
+
/** usage information for delayer */
void usage(char* argv[])
{
printf("usage: %s [options]\n", argv[0]);
printf(" -f addr : use addr, forward to that server, @port.\n");
printf(" -b addr : bind to this address to listen.\n");
- printf(" -p port : bind to this port (0 for random).\n");
+ printf(" -p port : bind to this port (use 0 for random).\n");
printf(" -m mem : use this much memory for waiting queries.\n");
printf(" -d delay: queries are delayed n milliseconds.\n");
printf(" -h : this help message\n");
exit(1);
}
+/** timeval compare, t1 < t2 */
+static int
+dl_tv_smaller(struct timeval* t1, const struct timeval* t2)
+{
+#ifndef S_SPLINT_S
+ if(t1->tv_sec < t2->tv_sec)
+ return 1;
+ if(t1->tv_sec == t2->tv_sec &&
+ t1->tv_usec < t2->tv_usec)
+ return 1;
+#endif
+ return 0;
+}
+
+/** timeval add, t1 += t2 */
+static void
+dl_tv_add(struct timeval* t1, const struct timeval* t2)
+{
+#ifndef S_SPLINT_S
+ t1->tv_sec += t2->tv_sec;
+ t1->tv_usec += t2->tv_usec;
+ while(t1->tv_usec > 1000000) {
+ t1->tv_usec -= 1000000;
+ t1->tv_sec++;
+ }
+#endif
+}
+
+/** timeval subtract, t1 -= t2 */
+static void
+dl_tv_subtract(struct timeval* t1, const struct timeval* t2)
+{
+#ifndef S_SPLINT_S
+ t1->tv_sec -= t2->tv_sec;
+ if(t1->tv_usec >= t2->tv_usec) {
+ t1->tv_usec -= t2->tv_usec;
+ } else {
+ t1->tv_sec--;
+ t1->tv_usec = 1000000-(t2->tv_usec-t1->tv_usec);
+ }
+#endif
+}
+
+
/** create new ring buffer */
static struct ringbuf*
ring_create(size_t sz)
free(r);
}
+/** add entry to ringbuffer */
+static void
+ring_add(struct ringbuf* r, ldns_buffer* pkt, struct timeval* now,
+ struct timeval* delay, struct proxy* p)
+{
+ /* time -- proxy* -- 16bitlen -- message */
+ uint16_t len = (uint16_t)ldns_buffer_limit(pkt);
+ struct timeval when;
+ size_t needed;
+ uint8_t* where = NULL;
+ log_assert(ldns_buffer_limit(pkt) <= 65535);
+ needed = sizeof(when) + sizeof(p) + sizeof(len) + len;
+ /* put item into ringbuffer */
+ if(r->low < r->high) {
+ /* used part is in the middle */
+ if(r->size - r->high >= needed) {
+ where = r->buf + r->high;
+ r->high += needed;
+ } else if(r->low > needed) {
+ /* wrap around ringbuffer */
+ /* make sure r->low == r->high means empty */
+ /* so r->low == r->high cannot be used to signify
+ * a completely full ringbuf */
+ if(r->size - r->high > sizeof(when)+sizeof(p)) {
+ /* zero entry at end of buffer */
+ memset(r->buf+r->high, 0,
+ sizeof(when)+sizeof(p));
+ }
+ where = r->buf;
+ r->high = needed;
+ } else {
+ /* drop message */
+ log_warn("warning: mem full, dropped message");
+ return;
+ }
+ } else {
+ /* empty */
+ if(r->high == r->low) {
+ where = r->buf;
+ r->low = 0;
+ r->high = needed;
+ /* unused part is in the middle */
+ /* so ringbuffer has wrapped around */
+ } else if(r->low - r->high > needed) {
+ where = r->buf + r->high;
+ r->high += needed;
+ } else {
+ log_warn("warning: mem full, dropped message");
+ return;
+ }
+ }
+ when = *now;
+ dl_tv_add(&when, delay);
+ /* copy it at where part */
+ log_assert(where != NULL);
+ memmove(where, &when, sizeof(when));
+ memmove(where+sizeof(when), &p, sizeof(p));
+ memmove(where+sizeof(when)+sizeof(p), &len, sizeof(len));
+ memmove(where+sizeof(when)+sizeof(p)+sizeof(len),
+ ldns_buffer_begin(pkt), len);
+}
+
+/** see if the ringbuffer is empty */
+static int
+ring_empty(struct ringbuf* r)
+{
+ return (r->low == r->high);
+}
+
+/** peek at timevalue for next item in ring */
+static struct timeval*
+ring_peek_time(struct ringbuf* r)
+{
+ if(ring_empty(r))
+ return NULL;
+ return (struct timeval*)&r->buf[r->low];
+}
+
+/** get entry from ringbuffer */
+static int
+ring_pop(struct ringbuf* r, ldns_buffer* pkt, struct timeval* tv,
+ struct proxy** p)
+{
+ /* time -- proxy* -- 16bitlen -- message */
+ uint16_t len;
+ uint8_t* where = NULL;
+ size_t done;
+ if(r->low == r->high)
+ return 0;
+ where = r->buf + r->low;
+ memmove(tv, where, sizeof(*tv));
+ memmove(p, where+sizeof(*tv), sizeof(*p));
+ memmove(&len, where+sizeof(*tv)+sizeof(*p), sizeof(len));
+ memmove(ldns_buffer_begin(pkt),
+ where+sizeof(*tv)+sizeof(*p)+sizeof(len), len);
+ ldns_buffer_set_limit(pkt, (size_t)len);
+ done = sizeof(*tv)+sizeof(*p)+sizeof(len)+len;
+ /* move lowmark */
+ if(r->low < r->high) {
+ /* used part in middle */
+ log_assert(r->high - r->low >= done);
+ r->low += done;
+ } else {
+ /* unused part in middle */
+ log_assert(r->size - r->low >= done);
+ r->low += done;
+ if(r->size - r->low > sizeof(*tv)+sizeof(*p)) {
+ /* see if it is zeroed; means end of buffer */
+ struct proxy* pz;
+ memmove(&pz, r->buf+r->low+sizeof(*tv), sizeof(pz));
+ if(pz == NULL)
+ r->low = 0;
+ } else r->low = 0;
+ }
+ if(r->low == r->high) {
+ r->low = 0; /* reset if empty */
+ r->high = 0;
+ }
+ return 1;
+}
+
/** signal handler global info */
static volatile int do_quit = 0;
do_quit = 1;
}
+/** send out waiting packets */
+static void
+service_send(struct ringbuf* ring, struct timeval* now, ldns_buffer* pkt,
+ struct sockaddr_storage* srv_addr, socklen_t srv_len)
+{
+ struct proxy* p;
+ struct timeval tv;
+ ssize_t sent;
+ while(!ring_empty(ring) &&
+ dl_tv_smaller(ring_peek_time(ring), now)) {
+ /* this items needs to be sent out */
+ if(!ring_pop(ring, pkt, &tv, &p))
+ fatal_exit("ringbuf error: pop failed");
+ verbose(1, "send out query %d.%6.6d",
+ (unsigned)tv.tv_sec, (unsigned)tv.tv_usec);
+ log_addr(1, "from client", &p->addr, p->addr_len);
+ /* send it */
+ sent = sendto(p->s, ldns_buffer_begin(pkt),
+ ldns_buffer_limit(pkt), 0,
+ (struct sockaddr*)srv_addr, srv_len);
+ if(sent == -1) {
+ log_err("sendto: %s", strerror(errno));
+ } else if(sent != (ssize_t)ldns_buffer_limit(pkt)) {
+ log_err("sendto: partial send");
+ }
+ p->lastuse = *now;
+ p->numsent++;
+ }
+}
+
+/** do proxy for one readable client */
+static void
+do_proxy(struct proxy* p, int retsock, ldns_buffer* pkt)
+{
+ int i;
+ ssize_t r;
+ for(i=0; i<TRIES_PER_SELECT; i++) {
+ r = recv(p->s, ldns_buffer_begin(pkt),
+ ldns_buffer_capacity(pkt), 0);
+ if(r == -1) {
+ if(errno == EAGAIN || errno == EINTR)
+ return;
+ log_err("recv: %s", strerror(errno));
+ return;
+ }
+ ldns_buffer_set_limit(pkt, (size_t)r);
+ log_addr(1, "return reply to client", &p->addr, p->addr_len);
+ /* send reply back to the real client */
+ p->numreturn++;
+ r = sendto(retsock, ldns_buffer_begin(pkt), (size_t)r, 0,
+ (struct sockaddr*)&p->addr, p->addr_len);
+ if(r == -1) {
+ log_err("sendto: %s", strerror(errno));
+ }
+ }
+}
+
+/** proxy return replies to clients */
+static void
+service_proxy(fd_set* rset, int retsock, struct proxy* proxies,
+ ldns_buffer* pkt, struct timeval* now)
+{
+ struct proxy* p;
+ for(p = proxies; p; p = p->next) {
+ if(FD_ISSET(p->s, rset)) {
+ p->lastuse = *now;
+ do_proxy(p, retsock, pkt);
+ }
+ }
+}
+
+/** find or else create proxy for this remote client */
+static struct proxy*
+find_create_proxy(struct sockaddr_storage* from, socklen_t from_len,
+ fd_set* rorig, int* max, struct proxy** proxies, int serv_ip6,
+ struct timeval* now)
+{
+ struct proxy* p;
+ struct timeval t;
+ struct timeval reuse_timeout;
+ for(p = *proxies; p; p = p->next) {
+ if(sockaddr_cmp(from, from_len, &p->addr, p->addr_len)==0)
+ return p;
+ }
+ /* possibly: reuse lapsed entries */
+ reuse_timeout.tv_sec = 1;
+ reuse_timeout.tv_usec = 0;
+ for(p = *proxies; p; p = p->next) {
+ if(p->numwait > p->numsent || p->numsent > p->numreturn)
+ continue;
+ t = *now;
+ dl_tv_subtract(&t, &p->lastuse);
+ if(dl_tv_smaller(&t, &reuse_timeout))
+ continue;
+ /* yes! */
+ verbose(1, "reuse existing entry");
+ memmove(&p->addr, from, from_len);
+ p->addr_len = from_len;
+ p->numreuse++;
+ return p;
+ }
+ /* create new */
+ p = calloc(1, sizeof(*p));
+ if(!p) fatal_exit("out of memory");
+ p->s = socket(serv_ip6?AF_INET6:AF_INET, SOCK_DGRAM, 0);
+ if(p->s == -1) fatal_exit("socket: %s", strerror(errno));
+ fd_set_nonblock(p->s);
+ memmove(&p->addr, from, from_len);
+ p->addr_len = from_len;
+ p->next = *proxies;
+ *proxies = p;
+ FD_SET(p->s, rorig);
+ if(p->s+1 > *max)
+ *max = p->s+1;
+ return p;
+}
+
+/** recv new waiting packets */
+static void
+service_recv(int s, struct ringbuf* ring, ldns_buffer* pkt,
+ fd_set* rorig, int* max, struct proxy** proxies,
+ struct sockaddr_storage* srv_addr, socklen_t srv_len,
+ struct timeval* now, struct timeval* delay)
+{
+ int i;
+ struct sockaddr_storage from;
+ socklen_t from_len;
+ ssize_t len;
+ struct proxy* p;
+ for(i=0; i<TRIES_PER_SELECT; i++) {
+ from_len = (socklen_t)sizeof(from);
+ len = recvfrom(s, ldns_buffer_begin(pkt),
+ ldns_buffer_capacity(pkt), 0,
+ (struct sockaddr*)&from, &from_len);
+ if(len < 0) {
+ if(errno == EAGAIN || errno == EINTR)
+ return;
+ fatal_exit("recvfrom: %s", strerror(errno));
+ }
+ ldns_buffer_set_limit(pkt, (size_t)len);
+ /* find its proxy element */
+ p = find_create_proxy(&from, from_len, rorig, max, proxies,
+ addr_is_ip6(srv_addr, srv_len), now);
+ if(!p) fatal_exit("error: cannot find or create proxy");
+ p->lastuse = *now;
+ ring_add(ring, pkt, now, delay, p);
+ p->numwait++;
+ log_addr(1, "recv from client", &p->addr, p->addr_len);
+ }
+}
+
+/** find waiting time */
+static int
+service_findwait(struct timeval* now, struct timeval* wait,
+ struct ringbuf* ring)
+{
+ /* first item is the time to wait */
+ struct timeval* peek = ring_peek_time(ring);
+ if(peek) {
+ memmove(wait, peek, sizeof(*wait));
+ dl_tv_subtract(wait, now);
+ return 1;
+ }
+ /* nothing, block */
+ return 0;
+}
+
+/** clear proxy list */
+static void
+proxy_list_clear(struct proxy* p)
+{
+ char from[109];
+ struct proxy* np;
+ int i=0, port;
+ while(p) {
+ np = p->next;
+ port = (int)ntohs(((struct sockaddr_in*)&p->addr)->sin_port);
+ if(addr_is_ip6(&p->addr, p->addr_len)) {
+ if(inet_ntop(AF_INET6,
+ &((struct sockaddr_in6*)&p->addr)->sin6_addr,
+ from, (socklen_t)sizeof(from)) == 0)
+ strncpy(from, "err", sizeof(from));
+ } else {
+ if(inet_ntop(AF_INET,
+ &((struct sockaddr_in*)&p->addr)->sin_addr,
+ from, (socklen_t)sizeof(from)) == 0)
+ strncpy(from, "err", sizeof(from));
+ }
+ printf("client[%d]: last %s@%d of %d : %u in, %u out, "
+ "%u returned\n", i++, from, port, (int)p->numreuse+1,
+ (unsigned)p->numwait, (unsigned)p->numsent,
+ (unsigned)p->numreturn);
+ close(p->s);
+ free(p);
+ p = np;
+ }
+}
+
+/** delayer service loop */
+static void
+service_loop(int udp_s, struct ringbuf* ring, struct timeval* delay,
+ struct sockaddr_storage* srv_addr, socklen_t srv_len,
+ ldns_buffer* pkt)
+{
+ fd_set rset, rorig;
+ struct timeval now, wait;
+ int max, have_wait = 0;
+ struct proxy* proxies = NULL;
+#ifndef S_SPLINT_S
+ FD_ZERO(&rorig);
+ FD_SET(udp_s, &rorig);
+#endif
+ max = udp_s + 1;
+ while(!do_quit) {
+ /* wait for events */
+ rset = rorig;
+ if(have_wait)
+ verbose(1, "wait for %d.%6.6d",
+ (unsigned)wait.tv_sec, (unsigned)wait.tv_usec);
+ else verbose(1, "wait");
+ if(select(max, &rset, NULL, NULL, have_wait?&wait:NULL) < 0) {
+ if(errno == EAGAIN || errno == EINTR)
+ continue;
+ fatal_exit("select: %s", strerror(errno));
+ }
+ /* get current time */
+ if(gettimeofday(&now, NULL) < 0) {
+ if(errno == EAGAIN || errno == EINTR)
+ continue;
+ fatal_exit("gettimeofday: %s", strerror(errno));
+ }
+ verbose(1, " ");
+ verbose(1, "process at %u.%6.6u",
+ (unsigned)now.tv_sec, (unsigned)now.tv_usec);
+ /* sendout delayed queries to master server (frees up buffer)*/
+ service_send(ring, &now, pkt, srv_addr, srv_len);
+ /* proxy return replies */
+ service_proxy(&rset, udp_s, proxies, pkt, &now);
+ /* see what can be received to start waiting */
+ service_recv(udp_s, ring, pkt, &rorig, &max, &proxies,
+ srv_addr, srv_len, &now, delay);
+ /* see what next timeout is (if any) */
+ have_wait = service_findwait(&now, &wait, ring);
+ }
+ proxy_list_clear(proxies);
+}
+
/** delayer main service routine */
static void
service(char* bind_str, int bindport, char* serv_str, size_t memsize,
socklen_t bind_len, srv_len;
struct ringbuf* ring = ring_create(memsize);
struct timeval delay;
- int s;
+ ldns_buffer* pkt;
+ int i, s;
delay.tv_sec = delay_msec / 1000;
delay.tv_usec = (delay_msec % 1000)*1000;
- if(bindport == 0)
- bindport = 1024 + random()%64000;
- if(!ipstrtoaddr(bind_str, bindport, &bind_addr, &bind_len)) {
- printf("cannot parse listen address: %s\n", bind_str);
- exit(1);
- }
if(!extstrtoaddr(serv_str, &srv_addr, &srv_len)) {
printf("cannot parse forward address: %s\n", serv_str);
exit(1);
}
+ pkt = ldns_buffer_new(65535);
+ if(!pkt)
+ fatal_exit("out of memory");
if( signal(SIGINT, delayer_sigh) == SIG_ERR ||
signal(SIGTERM, delayer_sigh) == SIG_ERR ||
signal(SIGHUP, delayer_sigh) == SIG_ERR ||
signal(SIGALRM, delayer_sigh) == SIG_ERR)
fatal_exit("could not bind to signal");
/* bind UDP port */
- if((s = socket(addr_is_ip6(&bind_addr, bind_len)?AF_INET6:AF_INET,
+ if((s = socket(str_is_ip6(bind_str)?AF_INET6:AF_INET,
SOCK_DGRAM, 0)) == -1)
fatal_exit("socket: %s", strerror(errno));
- if(bind(s, (struct sockaddr*)&bind_addr, bind_len) == -1)
- fatal_exit("bind: %s", strerror(errno));
+ i=0;
+ if(bindport == 0) {
+ bindport = 1024 + random()%64000;
+ i = 100;
+ }
+ while(1) {
+ if(!ipstrtoaddr(bind_str, bindport, &bind_addr, &bind_len)) {
+ printf("cannot parse listen address: %s\n", bind_str);
+ exit(1);
+ }
+ if(bind(s, (struct sockaddr*)&bind_addr, bind_len) == -1) {
+ log_err("bind: %s", strerror(errno));
+ if(i--==0)
+ fatal_exit("cannot bind any port");
+ bindport = 1024 + random()%64000;
+ } else break;
+ }
+ fd_set_nonblock(s);
printf("listening on port: %d\n", bindport);
/* process loop */
- /* wait for events */
- while(!do_quit) {
- /* get current time */
- /* sendout delayed queries to master server (frees up buffer)*/
- /* see what can be received to start waiting */
- /* see what next timeout is (if any) */
- }
+ do_quit = 0;
+ service_loop(s, ring, &delay, &srv_addr, srv_len, pkt);
+
/* cleanup */
+ verbose(1, "cleanup");
close(s);
+ ldns_buffer_free(pkt);
ring_delete(ring);
}
size_t memsize = 10*1024*1024;
int delay = 100;
+ verbosity = 0;
+ log_init(0, 0, 0);
+ log_ident_set("delayer");
srandom(time(NULL) ^ getpid());
+ if(argc == 1) usage(argv);
while( (c=getopt(argc, argv, "b:d:f:hm:p:")) != -1) {
switch(c) {
case 'b':
if(argc != 0)
usage(argv);
- printf("bind to %s @ %d and forward to %s\n"
- "after %d msec (buffer %d)\n",
- bindto, bindport, server, delay, (int)memsize);
+ printf("bind to %s @ %d and forward to %s after %d msec\n",
+ bindto, bindport, server, delay);
service(bindto, bindport, server, memsize, delay);
return 0;
}
projects / thirdparty / unbound.git / commitdiff
