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/*
* xml.c: a libFuzzer target to test several XML parser interfaces.
*
* See Copyright for the status of this software.
*/
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <libxml/catalog.h>
#include <libxml/parser.h>
#include <libxml/xmlerror.h>
#include <libxml/xmlmemory.h>
#include "fuzz.h"
#define XMLLINT_FUZZ
#include "../xmllint.c"
static const char *const switches[] = {
"--auto",
"--c14n",
"--c14n11",
"--compress",
"--copy",
"--debug",
"--debugent",
"--dropdtd",
"--dtdattr",
"--exc-c14n",
"--format",
"--htmlout",
"--huge",
"--insert",
"--loaddtd",
"--load-trace",
"--memory",
"--noblanks",
"--nocdata",
"--nocompact",
"--nodefdtd",
"--nodict",
"--noenc",
"--noent",
"--nofixup-base-uris",
"--nonet",
"--noout",
"--nowarning",
"--nowrap",
"--noxincludenode",
"--nsclean",
"--oldxml10",
"--pedantic",
"--postvalid",
"--push",
"--pushsmall",
"--quiet",
"--recover",
"--sax1",
"--testIO",
"--timing",
"--valid",
"--version",
"--walker",
"--xinclude",
"--xmlout"
};
static const size_t numSwitches = sizeof(switches) / sizeof(switches[0]);
struct {
const char **argv;
size_t argi;
} vars;
static void
pushArg(const char *str) {
vars.argv[vars.argi++] = str;
}
int
LLVMFuzzerInitialize(int *argc ATTRIBUTE_UNUSED,
char ***argv ATTRIBUTE_UNUSED) {
int fd;
/* Redirect stdout to /dev/null */
fd = open("/dev/null", O_WRONLY);
if (fd == -1) {
perror("/dev/null");
abort();
}
if (dup2(fd, STDOUT_FILENO) == -1) {
perror("dup2");
abort();
}
close(fd);
return 0;
}
int
LLVMFuzzerTestOneInput(const char *data, size_t size) {
char maxmemBuf[20];
char maxAmplBuf[20];
char prettyBuf[20];
const char *sval, *docBuffer, *docUrl;
size_t ssize, docSize, i;
unsigned uval;
int ival;
vars.argv = malloc((numSwitches + 5 + 6 * 2) * sizeof(vars.argv[0]));
vars.argi = 0;
pushArg("xmllint"),
pushArg("--nocatalogs");
xmlFuzzDataInit(data, size);
for (i = 0; i < numSwitches; i++) {
if (i % 32 == 0)
uval = xmlFuzzReadInt(4);
if ((uval & 1) && (switches[i] != NULL))
pushArg(switches[i]);
uval >>= 1;
}
/*
* Use four main parsing modes with equal probability
*/
switch (uval & 3) {
case 0:
/* XML parser */
break;
case 1:
/* HTML parser */
pushArg("--html");
break;
case 2:
/* XML reader */
pushArg("--stream");
break;
case 3:
/* SAX parser */
pushArg("--sax");
break;
}
uval = xmlFuzzReadInt(4);
if (uval > 0) {
if (size <= (INT_MAX - 2000) / 20)
uval %= size * 20 + 2000;
else
uval %= INT_MAX;
snprintf(maxmemBuf, 20, "%u", uval);
pushArg("--maxmem");
pushArg(maxmemBuf);
}
ival = xmlFuzzReadInt(1);
if (ival >= 1 && ival <= 5) {
snprintf(maxAmplBuf, 20, "%d", ival);
pushArg("--max-ampl");
pushArg(maxAmplBuf);
}
ival = xmlFuzzReadInt(1);
if (ival != 0) {
snprintf(prettyBuf, 20, "%d", ival - 128);
pushArg("--pretty");
pushArg(prettyBuf);
}
sval = xmlFuzzReadString(&ssize);
if (ssize > 0) {
pushArg("--encode");
pushArg(sval);
}
sval = xmlFuzzReadString(&ssize);
if (ssize > 0) {
pushArg("--pattern");
pushArg(sval);
}
sval = xmlFuzzReadString(&ssize);
if (ssize > 0) {
pushArg("--xpath");
pushArg(sval);
}
xmlFuzzReadEntities();
docBuffer = xmlFuzzMainEntity(&docSize);
docUrl = xmlFuzzMainUrl();
if (docBuffer == NULL || docUrl[0] == '-')
goto exit;
pushArg(docUrl);
pushArg(NULL);
xmlSetGenericErrorFunc(NULL, xmlFuzzErrorFunc);
xmlSetExternalEntityLoader(xmlFuzzEntityLoader);
#ifdef LIBXML_CATALOG_ENABLED
xmlCatalogSetDefaults(XML_CATA_ALLOW_NONE);
#endif
xmllintMain(vars.argi - 1, vars.argv);
xmlMemSetup(free, malloc, realloc, xmlMemStrdup);
exit:
xmlFuzzDataCleanup();
free(vars.argv);
return(0);
}
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