/*
- * libauthbind.c - bind(2)-redirector library for authbind
+ * udp-preload.c - testing mock library for secnet udp
+ * This file is part of secnet.
*
- * authbind is Copyright (C) 1998 Ian Jackson
+ * Copyright (C) 1998,2003-2004,2012,2017,2019 Ian Jackson
*
* This program 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 2, or (at your option)
+ * the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* 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
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
+ * 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.
*/
#define _GNU_SOURCE
kv= dlsym(RTLD_NEXT,name); if (kv) return kv;
dlerr= dlerror(); if (!dlerr) dlerr= "dlsym() failed for no reason";
- STDERRSTR_CONST("libauthbind: error finding original version of ");
+ STDERRSTR_CONST("udp-preload: error finding original version of ");
STDERRSTR_STRING(name);
STDERRSTR_CONST(": ");
STDERRSTR_STRING(dlerr);
}
#define socket_args int domain, int type, int protocol
+#define close_args int fd
#define bind_args int fd, const struct sockaddr *addr, socklen_t addrlen
+#define sendto_args int fd, const void *buf, size_t len, int flags, \
+ const struct sockaddr *addr, socklen_t addrlen
+#define recvfrom_args int fd, void *buf, size_t len, int flags, \
+ struct sockaddr *addr, socklen_t *addrlen
#define setsockopt_args int fd, int level, int optname, \
const void *optval, socklen_t optlen
-#define WRAPS(X) \
- X(socket, (domain,type,protocol)) \
- X(bind, (fd,addr,addrlen)) \
- X(setsockopt, (fd,level,optname,optval,optlen))
-
-#define DEF_OLD(fn,args) \
- typedef int fn##_fn_type(fn##_args); \
- static int find_##fn(fn##_args); \
+#define getsockname_args int fd, struct sockaddr *addr, socklen_t *addrlen
+#define WRAPS(X) \
+ X(socket, int, (domain,type,protocol)) \
+ X(close, int, (fd)) \
+ X(bind, int, (fd,addr,addrlen)) \
+ X(sendto, ssize_t, (fd,buf,len,flags,addr,addrlen)) \
+ X(recvfrom, ssize_t, (fd,buf,len,flags,addr,addrlen)) \
+ X(setsockopt, int, (fd,level,optname,optval,optlen)) \
+ X(getsockname,int, (fd,addr,addrlen))
+
+#define DEF_OLD(fn,rt,args) \
+ typedef rt fn##_fn_type(fn##_args); \
+ static rt find_##fn(fn##_args); \
static fn##_fn_type find_##fn, *old_##fn=find_##fn; \
- static int find_##fn(fn##_args) { \
+ static rt find_##fn(fn##_args) { \
anyfn_type *anyfn; \
anyfn= find_any(#fn); if (!anyfn) return -1; \
old_##fn= (fn##_fn_type*)anyfn; \
WRAPS(DEF_OLD)
#define WRAP(fn) int fn(fn##_args)
+#define TWRAP(fn) fn(fn##_args)
typedef struct{
int af;
static int tablesz;
static fdinfo *lookup(int fd) {
- if (fd>=tablesz) return 0;
+ if (fd<0 || fd>=tablesz) return 0;
return table[fd];
}
return 0;
}
+static int str2addrport(char *str,
+ struct sockaddr *addr, socklen_t *addrlen) {
+ union {
+ struct sockaddr_in sin;
+ struct sockaddr_in6 sin6;
+ } si;
+
+ memset(&si,0,sizeof(si));
+
+ int af;
+ void *iav;
+ uint16_t *portp;
+ socklen_t al;
+ switch (str[strcspn(str,".:")]) {
+ case '.': af=AF_INET ; iav=&si.sin .sin_addr ; al=sizeof(si.sin ); portp=&si.sin .sin_port ; break;
+ case ':': af=AF_INET6; iav=&si.sin6.sin6_addr; al=sizeof(si.sin6); portp=&si.sin6.sin6_port; break;
+ default: errno=ESRCH; return -1;
+ }
+ si.sin.sin_family=af;
+
+ char *comma=strchr(str,',');
+ if (!comma) { errno=ESRCH; return -1; }
+ *comma++=0;
+ int r=inet_pton(af,str,iav);
+//fprintf(stderr,"inet_pton(%d,\"%s\",)=%d\n",af,str,r);
+ if (r<0) return -1;
+ if (r==0) { errno=ENOTTY; return -1; }
+
+ char *ep;
+ errno=0;
+ unsigned long port=strtoul(comma,&ep,10);
+ if (ep==comma || *ep || errno || port>65536) { errno=ESRCH; return -1; }
+ *portp= htons(port);
+
+ if (addr) memcpy(addr,&si, *addrlen<al ? *addrlen : al);
+ *addrlen=al;
+ return 0;
+}
+
+static char *sun_prep(struct sockaddr_un *sun) {
+ const char *dir=getenv("UDP_PRELOAD_DIR");
+ if (!dir) { errno=ECHILD; return 0; }
+
+ memset(sun,0,sizeof(*sun));
+ sun->sun_family=AF_UNIX;
+ int dl = strlen(dir);
+ if (dl + 1 + ADDRPORTSTRLEN + 1 > sizeof(sun->sun_path)) {
+ errno=ENAMETOOLONG; return 0;
+ }
+ strcpy(sun->sun_path,dir);
+ char *p=sun->sun_path+dl;
+ *p++='/';
+ return p;
+}
+
WRAP(socket) {
if (!((domain==AF_INET || domain==AF_INET6) &&
type==SOCK_DGRAM))
return -1;
}
+WRAP(close) {
+ if (fd>=0 && fd<tablesz) {
+ free(table[fd]);
+ table[fd]=0;
+ }
+ return old_close(fd);
+}
+
WRAP(bind) {
fdinfo *ent=lookup(fd);
if (!ent) return old_bind(fd,addr,addrlen);
- const char *dir = getenv("UDP_PRELOAD_DIR");
- if (!dir) { errno=ECHILD; return -1; }
struct sockaddr_un sun;
- memset(&sun,0,sizeof(sun));
- sun.sun_family=AF_UNIX;
- int dl = strlen(dir);
- if (dl + 1 + ADDRPORTSTRLEN + 1 > sizeof(sun.sun_path)) {
- errno=ENAMETOOLONG; return -1;
- }
- strcpy(sun.sun_path,dir);
- char *p=sun.sun_path+dl;
- *p++='/';
+ char *p=sun_prep(&sun);
if (addrport2str(p,addr,addrlen)) return -1;
//fprintf(stderr,"binding %s\n",sun.sun_path);
if (unlink(sun.sun_path) && errno!=ENOENT) return -1;
errno=ENOTTY;
return -1;
}
+
+WRAP(getsockname) {
+ fdinfo *ent=lookup(fd);
+ if (!ent) return old_getsockname(fd,addr,addrlen);
+ struct sockaddr_un sun;
+ socklen_t sunlen=sizeof(sun);
+ if (old_getsockname(fd,(void*)&sun,&sunlen)) return -1;
+ if (sun.sun_family!=AF_UNIX || sunlen>sizeof(sun)) {
+//fprintf(stderr,"old_getsockname af=%lu sunlen=%lu\n",
+// (unsigned long)sun.sun_family,
+// (unsigned long)sunlen);
+ errno=EDOM; return -1;
+ }
+ char *slash=strrchr(sun.sun_path,'/');
+ if (str2addrport(slash ? slash+1 : sun.sun_path,
+ addr,addrlen)) return -1;
+ return 0;
+}
+
+ssize_t TWRAP(sendto) {
+ fdinfo *ent=lookup(fd);
+ if (!ent) return old_sendto(fd,buf,len,flags,addr,addrlen);
+
+ if (flags) { errno=ENOEXEC; return -1; }
+
+ const char *leaf=getenv("UDP_PRELOAD_SERVER");
+ if (!leaf) leaf="udp";
+ if (strlen(leaf) > ADDRPORTSTRLEN) { errno=ENAMETOOLONG; return -1; }
+ struct sockaddr_un sun;
+ char *p=sun_prep(&sun);
+ strcpy(p,leaf);
+
+ char tbuf[ADDRPORTSTRLEN+1];
+ memset(tbuf,0,sizeof(tbuf));
+ if (addrport2str(tbuf,addr,addrlen)) return -1;
+
+ struct iovec iov[2];
+ iov[0].iov_base=tbuf;
+ iov[0].iov_len=sizeof(tbuf);
+ iov[1].iov_base=(void*)buf;
+ iov[1].iov_len=len;
+
+ struct msghdr m;
+ memset(&m,0,sizeof(m));
+ m.msg_name=&sun;
+ m.msg_namelen=sizeof(sun);
+ m.msg_iov=iov;
+ m.msg_iovlen=2;
+
+ return sendmsg(fd,&m,0);
+}
+
+ssize_t TWRAP(recvfrom) {
+ fdinfo *ent=lookup(fd);
+ if (!ent) return old_recvfrom(fd,buf,len,flags,addr,addrlen);
+
+//fprintf(stderr,"recvfrom %d len=%lu flags=%d al=%lu\n",
+// fd, (unsigned long)len, flags, (unsigned long)*addrlen);
+
+ if (flags) { errno=ENOEXEC; return -1; }
+
+ char tbuf[ADDRPORTSTRLEN+1];
+
+ struct iovec iov[2];
+ iov[0].iov_base=tbuf;
+ iov[0].iov_len=sizeof(tbuf);
+ iov[1].iov_base=buf;
+ iov[1].iov_len=len;
+
+ struct msghdr m;
+ memset(&m,0,sizeof(m));
+ m.msg_iov=iov;
+ m.msg_iovlen=2;
+
+ ssize_t rr=recvmsg(fd,&m,0);
+ if (rr==-1) return rr;
+ if (rr<sizeof(tbuf)) { errno=ENXIO; return -1; }
+ if (tbuf[ADDRPORTSTRLEN]) { errno=E2BIG; return -1; }
+ if (str2addrport(tbuf,addr,addrlen)) {
+ fprintf(stderr, "recvfrom str2addrport `%s' %s\n",tbuf,
+ strerror(errno));
+ return -1;
+ }
+
+ rr -= sizeof(tbuf);
+//fprintf(stderr,"recvfrom %s %lu ok\n",tbuf,(unsigned long)rr);
+ return rr;
+}