netcdf-c/libdap2/dapattr.c
Dennis Heimbigner 4db4393e69 Begin changing over to use strlcat instead of strncat because
strlcat provides better protection against buffer overflows.

Code is taken from the FreeBSD project source code. Specifically:
https://github.com/freebsd/freebsd/blob/master/lib/libc/string/strlcat.c
License appears to be acceptable, but needs to be checked by e.g. Debian.

Step 1:
1. Add to netcdf-c/include/ncconfigure.h to use our version
   if not already available as determined by HAVE_STRLCAT in config.h.
2. Add the strlcat code to libdispatch/dstring.c
3. Turns out that strlcat was already defined in several places.
   So remove it from:
	ncgen3/genlib.c
	ncdump/dumplib.c
3. Define strlcat extern definition in ncconfigure.h.
4. Modify following directories to use strlcat:
	libdap2 libdap4 ncdap_test dap4_test
   Will do others in subsequent steps.
2017-11-23 10:55:24 -07:00

154 lines
4.4 KiB
C

/*********************************************************************
* Copyright 1993, UCAR/Unidata
* See netcdf/COPYRIGHT file for copying and redistribution conditions.
*********************************************************************/
#include "dapincludes.h"
#define OCCHECK(exp) if((ocstat = (exp))) {THROWCHK(ocstat); goto done;}
/* Forward */
static NCerror buildattribute(char*,nc_type,size_t,char**,NCattribute**);
/*
Invoke oc_merge_das and then extract special
attributes such as "strlen" and "dimname"
and stuff from DODS_EXTRA.
*/
int
dapmerge(NCDAPCOMMON* nccomm, CDFnode* ddsroot, OCddsnode dasroot)
{
int i,j;
NCerror ncstat = NC_NOERR;
OCerror ocstat = OC_NOERR;
NClist* allnodes;
OClink conn;
char* ocname = NULL;
char** values = NULL;
conn = nccomm->oc.conn;
if(ddsroot == NULL || dasroot == NULL)
return NC_NOERR;
/* Merge the das tree onto the dds tree */
ocstat = oc_merge_das(nccomm->oc.conn,dasroot,ddsroot->ocnode);
if(ocstat != OC_NOERR) goto done;
/* Create attributes on CDFnodes */
allnodes = ddsroot->tree->nodes;
for(i=0;i<nclistlength(allnodes);i++) {
CDFnode* node = (CDFnode*)nclistget(allnodes,i);
OCddsnode ocnode = node->ocnode;
size_t attrcount;
OCtype ocetype;
OCCHECK(oc_dds_attr_count(conn,ocnode,&attrcount));
for(j=0;j<attrcount;j++) {
size_t nvalues;
NCattribute* att = NULL;
if(ocname != NULL) {
free(ocname); ocname = NULL;
} /* from last loop */
OCCHECK(oc_dds_attr(conn,ocnode,j,&ocname,&ocetype,&nvalues,NULL));
if(nvalues > 0) {
values = (char**)malloc(sizeof(char*)*nvalues);
if(values == NULL) {ncstat = NC_ENOMEM; goto done;}
OCCHECK(oc_dds_attr(conn,ocnode,j,NULL,NULL,NULL,values));
}
ncstat = buildattribute(ocname,octypetonc(ocetype),nvalues,values,&att);
if(ncstat != NC_NOERR) goto done;
if(node->attributes == NULL)
node->attributes = nclistnew();
nclistpush(node->attributes,(void*)att);
if(strncmp(ocname,"DODS",strlen("DODS"))==0) {
att->invisible = 1;
/* Define extra semantics associated with
DODS and DODS_EXTRA attributes */
if(strcmp(ocname,"DODS.strlen")==0
|| strcmp(ocname,"DODS_EXTRA.strlen")==0) {
unsigned int maxstrlen = 0;
if(values != NULL) {
if(0==sscanf(values[0],"%u",&maxstrlen))
maxstrlen = 0;
}
node->dodsspecial.maxstrlen = maxstrlen;
#ifdef DEBUG
fprintf(stderr,"%s.maxstrlen=%d\n",node->ocname,(int)node->dodsspecial.maxstrlen);
#endif
} else if(strcmp(ocname,"DODS.dimName")==0
|| strcmp(ocname,"DODS_EXTRA.dimName")==0) {
if(values != NULL) {
node->dodsspecial.dimname = nulldup(values[0]);
#ifdef DEBUG
fprintf(stderr,"%s.dimname=%s\n",node->ocname,node->dodsspecial.dimname);
#endif
} else node->dodsspecial.dimname = NULL;
} else if(strcmp(ocname,"DODS.Unlimited_Dimension")==0
|| strcmp(ocname,"DODS_EXTRA.Unlimited_Dimension")==0) {
char* val0 = NULL;
if(values != NULL)
val0 = values[0];
if(val0 != NULL) {
if(nccomm->cdf.recorddimname != NULL) {
if(strcmp(nccomm->cdf.recorddimname,val0)!=0)
nclog(NCLOGWARN,"Duplicate DODS_EXTRA:Unlimited_Dimension specifications");
} else {
nccomm->cdf.recorddimname = nulldup(values[0]);
#ifdef DEBUG
fprintf(stderr,"%s.Unlimited_Dimension=%s\n",node->ocname,nccomm->cdf.recorddimname);
#endif
}
}
}
}
/* clean up */
if(values) {
oc_reclaim_strings(nvalues,values);
free(values);
values = NULL;
}
}
}
done:
if(values != NULL) free(values);
if(ocname != NULL) free(ocname);
if(ocstat != OC_NOERR) ncstat = ocerrtoncerr(ocstat);
return THROW(ncstat);
}
/*
Build an NCattribute
from a DAP attribute.
As of Jun 27, 2017, we modify
to suppress nul characters and terminate
the name at the first nul.
*/
static NCerror
buildattribute(char* name, nc_type ptype,
size_t nvalues, char** values, NCattribute** attp)
{
int i;
NCerror ncstat = NC_NOERR;
NCattribute* att = NULL;
att = (NCattribute*)calloc(1,sizeof(NCattribute));
MEMCHECK(att,NC_ENOMEM);
att->name = nulldup(name);
att->etype = ptype;
att->values = nclistnew();
for(i=0;i<nvalues;i++) {
char* copy = nulldup(values[i]);
nclistpush(att->values,(void*)copy);
}
if(attp) *attp = att;
else
free(att);
return THROW(ncstat);
}