WIP dns transport packets etc.

[secnet.git] / udp.c

diff --git a/udp.c b/udp.c
index 4c393cd603cf397499c206632e2061c9b1947ef9..14311353472e7a7b65783e716519203135206162 100644 (file)
--- a/udp.c
+++ b/udp.c
@@ -16,6 +16,8 @@
 #include <errno.h>
 #include <sys/socket.h>
 #include <sys/wait.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
 #include "util.h"
 #include "unaligned.h"
 #include "ipaddr.h"
@@ -32,6 +34,11 @@ struct notify_list {
     struct notify_list *next;
 };
 
+struct peer_config {
+    string_t address; /* DNS name for bootstrapping, optional */
+    int remoteport; /* Port for bootstrapping, optional */
+};
+
 struct udp {
     closure_t cl;
     struct comm_if ops;
@@ -42,10 +49,94 @@ struct udp {
     string_t authbind;
     struct buffer_if *rbuf;
     struct notify_list *notify;
+    struct resolver_if *resolver;
     bool_t use_proxy;
     struct sockaddr_in proxy;
 };
 
+static const char *saddr_to_string(const struct sockaddr_in *sin) {
+    static char bufs[2][100];
+    static int b;
+
+    b ^= 1;
+    snprintf(bufs[b], sizeof(bufs[b]), "[%s]:%d",
+            inet_ntoa(sin->sin_addr),
+            ntohs(sin->sin_port));
+    return bufs[b];
+}
+
+static const char *addr_to_string(void *commst, const struct comm_addr *ca) {
+    struct udp *st=commst;
+    static char sbuf[100];
+
+    struct sockaddr_in la;
+    la.sin_addr.s_addr=htonl(st->addr);
+    la.sin_port=htons(st->port);
+
+    snprintf(sbuf, sizeof(sbuf), "udp:%s-%s",
+            saddr_to_string(&la), saddr_to_string(&ca->priv.sin));
+    return sbuf;
+}
+
+struct peer_addr_cst {
+    struct udp *udp;
+    struct peer_config *cfg;
+    comm_peer_addr_answer_fn *cb;
+    void *cst;
+};
+
+static void *peer_addr_config(void *commst, dict_t *dict, struct cloc loc,
+                             cstring_t desc)
+{
+    struct peer_config *cfg;
+    cfg=safe_malloc(sizeof(*cfg),"peer addr config");
+    cfg->address=dict_read_string(dict, "address",False,desc,loc);
+    if (cfg->address)
+       cfg->remoteport=dict_read_number(dict,"port",True,desc,loc,0);
+    else cfg->remoteport=0;
+    if (cfg->address)
+       return cfg;
+    free(cfg);
+    return NULL;
+}
+
+static void peer_resolve_callback(void *sst, struct in_addr *address)
+{
+    struct peer_addr_cst *pacst=sst;
+    struct udp *st=pacst->udp;
+    struct peer_config *cfg=pacst->cfg;
+    struct comm_addr ca;
+    if (address) {
+       FILLZERO(ca);
+       ca.comm=&st->ops;
+       ca.priv.sin.sin_family=AF_INET;
+       ca.priv.sin.sin_port=htons(cfg->remoteport);
+       ca.priv.sin.sin_addr=*address;
+       pacst->cb(pacst->cst,&ca);
+    } else {
+       pacst->cb(pacst->cst,0);
+    }
+    free(pacst);
+}
+
+static bool_t peer_addr_request(void *commst, void *from_peer_config,
+                               comm_peer_addr_answer_fn *cb, void *cst)
+{
+    struct udp *st=commst;
+    struct peer_config *cfg=from_peer_config;
+    struct peer_addr_cst *pacst;
+    pacst=safe_malloc(sizeof(*pacst),"udp peer addr request cst");
+    pacst->udp=st;
+    pacst->cfg=cfg;
+    pacst->cb=cb;
+    pacst->cst=cst;
+    bool_t ok=st->resolver->request(st->resolver->st,cfg->address,
+                                   peer_resolve_callback,pacst);
+    if (!ok)
+       free(pacst);
+    return ok;
+}
+
 static int udp_beforepoll(void *state, struct pollfd *fds, int *nfds_io,
                          int *timeout_io)
 {
@@ -71,6 +162,7 @@ static void udp_afterpoll(void *state, struct pollfd *fds, int nfds)
 
     if (nfds && (fds->revents & POLLIN)) {
        do {
+           FILLZERO(from);
            fromlen=sizeof(from);
            BUF_ASSERT_FREE(st->rbuf);
            BUF_ALLOC(st->rbuf,"udp_afterpoll");
@@ -95,7 +187,11 @@ static void udp_afterpoll(void *state, struct pollfd *fds, int nfds)
                }
                done=False;
                for (n=st->notify; n; n=n->next) {
-                   if (n->fn(n->state, st->rbuf, &from)) {
+                   struct comm_addr ca;
+                   FILLZERO(ca);
+                   ca.comm=&st->ops;
+                   ca.priv.sin=from;
+                   if (n->fn(n->state, st->rbuf, &ca)) {
                        done=True;
                        break;
                    }
@@ -156,21 +252,21 @@ static void release_notify(void *commst, void *nst, comm_notify_fn *fn)
 }
 
 static bool_t udp_sendmsg(void *commst, struct buffer_if *buf,
-                         struct sockaddr_in *dest)
+                         const struct comm_addr *dest)
 {
     struct udp *st=commst;
     uint8_t *sa;
 
     if (st->use_proxy) {
        sa=buf->start-8;
-       memcpy(sa,&dest->sin_addr,4);
+       memcpy(sa,&dest->priv.sin.sin_addr,4);
        memset(sa+4,0,4);
-       memcpy(sa+6,&dest->sin_port,2);
+       memcpy(sa+6,&dest->priv.sin.sin_port,2);
        sendto(st->fd,sa,buf->size+8,0,(struct sockaddr *)&st->proxy,
               sizeof(st->proxy));
     } else {
        sendto(st->fd, buf->start, buf->size, 0,
-              (struct sockaddr *)dest, sizeof(*dest));
+              (struct sockaddr *)&dest->priv.sin, sizeof(dest->priv.sin));
     }
 
     return True;
@@ -194,7 +290,7 @@ static void udp_phase_hook(void *sst, uint32_t new_phase)
                     st->loc.file,st->loc.line);
     }
 
-    memset(&addr, 0, sizeof(addr));
+    FILLZERO(addr);
     addr.sin_family=AF_INET;
     addr.sin_addr.s_addr=htonl(st->addr);
     addr.sin_port=htons(st->port);
@@ -262,6 +358,9 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
     st->ops.request_notify=request_notify;
     st->ops.release_notify=release_notify;
     st->ops.sendmsg=udp_sendmsg;
+    st->ops.peer_addr_config=peer_addr_config;
+    st->ops.peer_addr_request=peer_addr_request;
+    st->ops.addr_to_string=addr_to_string;
     st->port=0;
     st->use_proxy=False;
 
@@ -272,14 +371,14 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
     d=i->data.dict;
 
     j=dict_find_item(d,"address",False,"udp",st->loc);
-    st->addr=j?st->addr=string_item_to_ipaddr(j, "udp"):INADDR_ANY;
+    st->addr=j?string_item_to_ipaddr(j, "udp"):INADDR_ANY;
     st->port=dict_read_number(d,"port",True,"udp",st->loc,0);
     st->rbuf=find_cl_if(d,"buffer",CL_BUFFER,True,"udp",st->loc);
     st->authbind=dict_read_string(d,"authbind",False,"udp",st->loc);
     l=dict_lookup(d,"proxy");
     if (l) {
        st->use_proxy=True;
-       memset(&st->proxy,0,sizeof(st->proxy));
+       FILLZERO(st->proxy);
        st->proxy.sin_family=AF_INET;
        i=list_elem(l,0);
        if (!i || i->type!=t_string) {
@@ -294,6 +393,7 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context,
        st->proxy.sin_port=htons(i->data.number);
        st->ops.min_start_pad=8;
     }
+    st->resolver=find_cl_if(d,"resolver",CL_RESOLVER,True,"comm",loc);
 
     add_hook(PHASE_GETRESOURCES,udp_phase_hook,st);