/* Hashes a file onto the provided buffer and looks it up the cache.
Returns CL_VIRUS if found, CL_CLEAN if not FIXME or a recoverable error,
and returns CL_EREAD if unrecoverable */
int cache_check(unsigned char *hash, cli_ctx *ctx) {
fmap_t *map;
size_t todo, at = 0;
cli_md5_ctx md5;
int ret;
if(!ctx || !ctx->engine || !ctx->engine->cache)
return CL_VIRUS;
map = *ctx->fmap;
todo = map->len;
cli_md5_init(&md5);
while(todo) {
const void *buf;
size_t readme = todo < FILEBUFF ? todo : FILEBUFF;
if(!(buf = fmap_need_off_once(map, at, readme)))
return CL_EREAD;
todo -= readme;
at += readme;
if (cli_md5_update(&md5, buf, readme)) {
cli_errmsg("cache_check: error reading while generating hash!\n");
return CL_EREAD;
}
}
cli_md5_final(hash, &md5);
ret = cache_lookup_hash(hash, map->len, ctx->engine->cache, ctx->recursion);
cli_dbgmsg("cache_check: %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x is %s\n", hash[0], hash[1], hash[2], hash[3], hash[4], hash[5], hash[6], hash[7], hash[8], hash[9], hash[10], hash[11], hash[12], hash[13], hash[14], hash[15], (ret == CL_VIRUS) ? "negative" : "positive");
return ret;
}
int cli_fmap_scandesc(cli_ctx *ctx, cli_file_t ftype, uint8_t ftonly, struct cli_matched_type **ftoffset, unsigned int acmode, struct cli_ac_result **acres, unsigned char *refhash)
{
const unsigned char *buff;
int ret = CL_CLEAN, type = CL_CLEAN, bytes, compute_hash[CLI_HASH_AVAIL_TYPES];
unsigned int i = 0, bm_offmode = 0;
uint32_t maxpatlen, offset = 0;
struct cli_ac_data gdata, tdata;
struct cli_bm_off toff;
cli_md5_ctx md5ctx;
SHA256_CTX sha256ctx;
SHA1Context sha1ctx;
unsigned char digest[CLI_HASH_AVAIL_TYPES][32];
struct cli_matcher *groot = NULL, *troot = NULL;
struct cli_target_info info;
fmap_t *map = *ctx->fmap;
struct cli_matcher *hdb, *fp;
const char *virname = NULL;
uint32_t viroffset = 0;
uint32_t viruses_found = 0;
if(!ctx->engine) {
cli_errmsg("cli_scandesc: engine == NULL\n");
return CL_ENULLARG;
}
if(!ftonly)
groot = ctx->engine->root[0]; /* generic signatures */
if(ftype) {
for(i = 1; i < CLI_MTARGETS; i++) {
if(cli_mtargets[i].target == ftype) {
troot = ctx->engine->root[i];
break;
}
}
}
if(ftonly) {
if(!troot)
return CL_CLEAN;
maxpatlen = troot->maxpatlen;
} else {
if(troot)
maxpatlen = MAX(troot->maxpatlen, groot->maxpatlen);
else
maxpatlen = groot->maxpatlen;
}
targetinfo(&info, i, map);
if(!ftonly)
if((ret = cli_ac_initdata(&gdata, groot->ac_partsigs, groot->ac_lsigs, groot->ac_reloff_num, CLI_DEFAULT_AC_TRACKLEN)) || (ret = cli_ac_caloff(groot, &gdata, &info))) {
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
if(troot) {
if((ret = cli_ac_initdata(&tdata, troot->ac_partsigs, troot->ac_lsigs, troot->ac_reloff_num, CLI_DEFAULT_AC_TRACKLEN)) || (ret = cli_ac_caloff(troot, &tdata, &info))) {
if(!ftonly)
cli_ac_freedata(&gdata);
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
if(troot->bm_offmode) {
if(map->len >= CLI_DEFAULT_BM_OFFMODE_FSIZE) {
if((ret = cli_bm_initoff(troot, &toff, &info))) {
if(!ftonly)
cli_ac_freedata(&gdata);
cli_ac_freedata(&tdata);
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
bm_offmode = 1;
}
}
}
hdb = ctx->engine->hm_hdb;
fp = ctx->engine->hm_fp;
if(!ftonly && hdb) {
if(!refhash) {
if(cli_hm_have_size(hdb, CLI_HASH_MD5, map->len) || cli_hm_have_size(fp, CLI_HASH_MD5, map->len)) {
cli_md5_init(&md5ctx);
compute_hash[CLI_HASH_MD5] = 1;
} else
compute_hash[CLI_HASH_MD5] = 0;
} else {
compute_hash[CLI_HASH_MD5] = 0;
memcpy(digest[CLI_HASH_MD5], refhash, 16);
}
if(cli_hm_have_size(hdb, CLI_HASH_SHA1, map->len) || cli_hm_have_wild(hdb, CLI_HASH_SHA1)
|| cli_hm_have_size(fp, CLI_HASH_SHA1, map->len) || cli_hm_have_wild(fp, CLI_HASH_SHA1) ) {
SHA1Init(&sha1ctx);
compute_hash[CLI_HASH_SHA1] = 1;
} else
compute_hash[CLI_HASH_SHA1] = 0;
if(cli_hm_have_size(hdb, CLI_HASH_SHA256, map->len) || cli_hm_have_wild(hdb, CLI_HASH_SHA256)
|| cli_hm_have_size(fp, CLI_HASH_SHA256, map->len) || cli_hm_have_wild(fp, CLI_HASH_SHA256)) {
sha256_init(&sha256ctx);
compute_hash[CLI_HASH_SHA256] = 1;
} else
compute_hash[CLI_HASH_SHA256] = 0;
}
while(offset < map->len) {
bytes = MIN(map->len - offset, SCANBUFF);
if(!(buff = fmap_need_off_once(map, offset, bytes)))
break;
if(ctx->scanned)
*ctx->scanned += bytes / CL_COUNT_PRECISION;
if (ctx->engine->cb_progress && map->handle_is_fd && !ctx->engine->cb_progress((ssize_t) map->handle, bytes, ctx->engine->cb_progress_ctx))
return CL_BREAK;
if(troot) {
virname = NULL;
viroffset = 0;
ret = matcher_run(troot, buff, bytes, &virname, &tdata, offset, &info, ftype, ftoffset, acmode, acres, map, bm_offmode ? &toff : NULL, &viroffset, ctx);
if (virname) {
/* virname already appended by matcher_run */
viruses_found = 1;
}
if((ret == CL_VIRUS && !SCAN_ALL) || ret == CL_EMEM) {
if(!ftonly)
cli_ac_freedata(&gdata);
cli_ac_freedata(&tdata);
if(bm_offmode)
cli_bm_freeoff(&toff);
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
}
if(!ftonly) {
virname = NULL;
viroffset = 0;
ret = matcher_run(groot, buff, bytes, &virname, &gdata, offset, &info, ftype, ftoffset, acmode, acres, map, NULL, &viroffset, ctx);
if (virname) {
/* virname already appended by matcher_run */
viruses_found = 1;
}
if((ret == CL_VIRUS && !SCAN_ALL) || ret == CL_EMEM) {
cli_ac_freedata(&gdata);
if(troot) {
cli_ac_freedata(&tdata);
if(bm_offmode)
cli_bm_freeoff(&toff);
}
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
} else if((acmode & AC_SCAN_FT) && ret >= CL_TYPENO) {
if(ret > type)
type = ret;
}
if(hdb && !SCAN_ALL) {
const void *data = buff + maxpatlen * (offset!=0);
uint32_t data_len = bytes - maxpatlen * (offset!=0);
if(compute_hash[CLI_HASH_MD5])
cli_md5_update(&md5ctx, data, data_len);
if(compute_hash[CLI_HASH_SHA1])
SHA1Update(&sha1ctx, data, data_len);
if(compute_hash[CLI_HASH_SHA256])
sha256_update(&sha256ctx, data, data_len);
}
}
if(SCAN_ALL && viroffset) {
offset = viroffset;
continue;
}
if(bytes < SCANBUFF) break;
offset += bytes - maxpatlen;
}
if(!ftonly && hdb) {
enum CLI_HASH_TYPE hashtype, hashtype2;
if(compute_hash[CLI_HASH_MD5])
cli_md5_final(digest[CLI_HASH_MD5], &md5ctx);
if(refhash)
compute_hash[CLI_HASH_MD5] = 1;
if(compute_hash[CLI_HASH_SHA1])
SHA1Final(&sha1ctx, digest[CLI_HASH_SHA1]);
if(compute_hash[CLI_HASH_SHA256])
sha256_final(&sha256ctx, digest[CLI_HASH_SHA256]);
virname = NULL;
for(hashtype = CLI_HASH_MD5; hashtype < CLI_HASH_AVAIL_TYPES; hashtype++) {
const char * virname_w = NULL;
int found = 0;
/* If no hash, skip to next type */
if(!compute_hash[hashtype])
continue;
/* Do hash scan */
if((ret = cli_hm_scan(digest[hashtype], map->len, &virname, hdb, hashtype)) == CL_VIRUS) {
found += 1;
}
if(!found || SCAN_ALL) {
if ((ret = cli_hm_scan_wild(digest[hashtype], &virname_w, hdb, hashtype)) == CL_VIRUS)
found += 2;
}
/* If found, do immediate hash-only FP check */
if (found && fp) {
for(hashtype2 = CLI_HASH_MD5; hashtype2 < CLI_HASH_AVAIL_TYPES; hashtype2++) {
if(!compute_hash[hashtype2])
continue;
if(cli_hm_scan(digest[hashtype2], map->len, NULL, fp, hashtype2) == CL_VIRUS) {
found = 0;
ret = CL_CLEAN;
break;
}
else if(cli_hm_scan_wild(digest[hashtype2], NULL, fp, hashtype2) == CL_VIRUS) {
found = 0;
ret = CL_CLEAN;
break;
}
}
}
/* If matched size-based hash ... */
if (found % 2) {
viruses_found = 1;
cli_append_virus(ctx, virname);
if (!SCAN_ALL)
break;
virname = NULL;
}
/* If matched size-agnostic hash ... */
if (found > 1) {
viruses_found = 1;
cli_append_virus(ctx, virname_w);
if (!SCAN_ALL)
break;
}
}
}
if(troot) {
if(ret != CL_VIRUS || SCAN_ALL)
ret = cli_lsig_eval(ctx, troot, &tdata, &info, refhash);
if (ret == CL_VIRUS)
viruses_found++;
cli_ac_freedata(&tdata);
if(bm_offmode)
cli_bm_freeoff(&toff);
}
if(groot) {
if(ret != CL_VIRUS || SCAN_ALL)
ret = cli_lsig_eval(ctx, groot, &gdata, &info, refhash);
cli_ac_freedata(&gdata);
}
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
if (SCAN_ALL && viruses_found)
return CL_VIRUS;
if(ret == CL_VIRUS)
return CL_VIRUS;
return (acmode & AC_SCAN_FT) ? type : CL_CLEAN;
}
int cli_fmap_scandesc(cli_ctx *ctx, cli_file_t ftype, uint8_t ftonly, struct cli_matched_type **ftoffset, unsigned int acmode, struct cli_ac_result **acres, unsigned char *refhash)
{
//CHR ftype => type == CL_TYPE_TEXT_ASCII ? 0 : type
//CHR ftonly => 0
cli_infomsg(NULL,"DEBUG: in cli_fmap_scandesc\n");//CHR
const unsigned char *buff;
int ret = CL_CLEAN, type = CL_CLEAN, bytes, compute_hash[CLI_HASH_AVAIL_TYPES];
unsigned int i = 0, bm_offmode = 0;
uint32_t maxpatlen, offset = 0;
struct cli_ac_data gdata, tdata;
struct cli_bm_off toff;
cli_md5_ctx md5ctx;
SHA256_CTX sha256ctx;
SHA1Context sha1ctx;
unsigned char digest[CLI_HASH_AVAIL_TYPES][32];
struct cli_matcher *groot = NULL, *troot = NULL;
struct cli_target_info info;
fmap_t *map = *ctx->fmap;
struct cli_matcher *hdb, *fp;
const char *virname = NULL;
uint32_t viroffset = 0;
uint32_t viruses_found = 0;
if(!ctx->engine) {
cli_errmsg("cli_scandesc: engine == NULL\n");
return CL_ENULLARG;
}
cli_infomsg(NULL,"DEBUG: ftype=%d, ftonly=%d(using generic signatures for groot)\n",ftype,ftonly);//CHR
if(!ftonly)
groot = ctx->engine->root[0]; /* generic signatures */
//CHR in test.txt case, ftype=0, troot is for sepcific types: from 1 to CLI_MTARGETS
if(ftype) {
for(i = 1; i < CLI_MTARGETS; i++) {
if(cli_mtargets[i].target == ftype) {
troot = ctx->engine->root[i];
break;
}
}
}
if(ftonly) {
if(!troot)
return CL_CLEAN;
maxpatlen = troot->maxpatlen;
} else {
if(troot)
maxpatlen = MAX(troot->maxpatlen, groot->maxpatlen);
else{
maxpatlen = groot->maxpatlen;
cli_infomsg(NULL,"DEBUG: no troot, maxpatlen using groot->maxpatlen=%d\n",groot->maxpatlen);//CHR
}
}
targetinfo(&info, i, map);
if(!ftonly)
// CHR init AC scan structure?
if((ret = cli_ac_initdata(&gdata, groot->ac_partsigs, groot->ac_lsigs, groot->ac_reloff_num, CLI_DEFAULT_AC_TRACKLEN)) || (ret = cli_ac_caloff(groot, &gdata, &info))) {
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
// not run in this case test.txt
if(troot) {
if((ret = cli_ac_initdata(&tdata, troot->ac_partsigs, troot->ac_lsigs, troot->ac_reloff_num, CLI_DEFAULT_AC_TRACKLEN)) || (ret = cli_ac_caloff(troot, &tdata, &info))) {
if(!ftonly)
cli_ac_freedata(&gdata);
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
if(troot->bm_offmode) {// CHR offset mode
if(map->len >= CLI_DEFAULT_BM_OFFMODE_FSIZE) {
if((ret = cli_bm_initoff(troot, &toff, &info))) {
if(!ftonly)
cli_ac_freedata(&gdata);
cli_ac_freedata(&tdata);
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
bm_offmode = 1;
}
}
}
hdb = ctx->engine->hm_hdb;
fp = ctx->engine->hm_fp;
// hdb related
if(!ftonly && hdb) { //CHR if have hdb should init mn5 contex
if(!refhash) {
if(cli_hm_have_size(hdb, CLI_HASH_MD5, map->len) || cli_hm_have_size(fp, CLI_HASH_MD5, map->len)) {
cli_md5_init(&md5ctx);
compute_hash[CLI_HASH_MD5] = 1;
} else
compute_hash[CLI_HASH_MD5] = 0;
} else {
compute_hash[CLI_HASH_MD5] = 0;
memcpy(digest[CLI_HASH_MD5], refhash, 16);
}
if(cli_hm_have_size(hdb, CLI_HASH_SHA1, map->len) || cli_hm_have_size(fp, CLI_HASH_SHA1, map->len)) {
SHA1Init(&sha1ctx);
compute_hash[CLI_HASH_SHA1] = 1;
} else
compute_hash[CLI_HASH_SHA1] = 0;
if(cli_hm_have_size(hdb, CLI_HASH_SHA256, map->len) || cli_hm_have_size(fp, CLI_HASH_SHA256, map->len)) {
sha256_init(&sha256ctx);
compute_hash[CLI_HASH_SHA256] = 1;
} else
compute_hash[CLI_HASH_SHA256] = 0;
}
while(offset < map->len) {
bytes = MIN(map->len - offset, SCANBUFF);
if(!(buff = fmap_need_off_once(map, offset, bytes)))
break;
if(ctx->scanned)
*ctx->scanned += bytes / CL_COUNT_PRECISION;
// CHR not troot for this case
if(troot) {
cli_infomsg(NULL,"DEBUG: not troot, should not show this msg\n");//CHR
virname = NULL;
viroffset = 0;
// CHR run match
ret = matcher_run(troot, buff, bytes, &virname, &tdata, offset, &info, ftype, ftoffset, acmode, acres, map, bm_offmode ? &toff : NULL, &viroffset, ctx);
if (virname) {
viruses_found++;
}
if((ret == CL_VIRUS && !SCAN_ALL) || ret == CL_EMEM) {
if(!ftonly)
cli_ac_freedata(&gdata);
cli_ac_freedata(&tdata);
if(bm_offmode)
cli_bm_freeoff(&toff);
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
}
}
if(!ftonly) {
cli_infomsg(NULL,"DEBUG: !ftonly=true, will run matcher_run with groot with generic sigs\n");//CHR
virname = NULL;
viroffset = 0;
ret = matcher_run(groot, buff, bytes, &virname, &gdata, offset, &info, ftype, ftoffset, acmode, acres, map, NULL, &viroffset, ctx);
if (virname) {
viruses_found++;
}
if((ret == CL_VIRUS && !SCAN_ALL) || ret == CL_EMEM) {
cli_ac_freedata(&gdata);
if(troot) {
cli_ac_freedata(&tdata);
if(bm_offmode)
cli_bm_freeoff(&toff);
}
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
return ret;
} else if((acmode & AC_SCAN_FT) && ret >= CL_TYPENO) {
if(ret > type)
type = ret;
}
if(hdb && !SCAN_ALL) {
const void *data = buff + maxpatlen * (offset!=0);
uint32_t data_len = bytes - maxpatlen * (offset!=0);
if(compute_hash[CLI_HASH_MD5])
cli_md5_update(&md5ctx, data, data_len);
if(compute_hash[CLI_HASH_SHA1])
SHA1Update(&sha1ctx, data, data_len);
if(compute_hash[CLI_HASH_SHA256])
sha256_update(&sha256ctx, data, data_len);
}
}
if(SCAN_ALL && viroffset) {
offset = viroffset;
continue;
}
if(bytes < SCANBUFF) break;
offset += bytes - maxpatlen;
}
if(!ftonly && hdb) {
enum CLI_HASH_TYPE hashtype, hashtype2;
if(compute_hash[CLI_HASH_MD5])
cli_md5_final(digest[CLI_HASH_MD5], &md5ctx);
if(refhash)
compute_hash[CLI_HASH_MD5] = 1;
if(compute_hash[CLI_HASH_SHA1])
SHA1Final(&sha1ctx, digest[CLI_HASH_SHA1]);
if(compute_hash[CLI_HASH_SHA256])
sha256_final(&sha256ctx, digest[CLI_HASH_SHA256]);
virname = NULL;
for(hashtype = CLI_HASH_MD5; hashtype < CLI_HASH_AVAIL_TYPES; hashtype++) {
if(compute_hash[hashtype] &&
(ret = cli_hm_scan(digest[hashtype], map->len, &virname, hdb, hashtype)) == CL_VIRUS) {
if(fp) {
for(hashtype2 = CLI_HASH_MD5; hashtype2 < CLI_HASH_AVAIL_TYPES; hashtype2++) {
if(compute_hash[hashtype2] &&
cli_hm_scan(digest[hashtype2], map->len, NULL, fp, hashtype2) == CL_VIRUS) {
ret = CL_CLEAN;
break;
}
}
}
if (ret == CL_VIRUS) {
viruses_found++;
cli_append_virus(ctx, virname);
if (!SCAN_ALL)
break;
}
virname = NULL;
}
}
}
if(troot) {
if(ret != CL_VIRUS || SCAN_ALL)
ret = cli_lsig_eval(ctx, troot, &tdata, &info, refhash);
if (ret == CL_VIRUS)
viruses_found++;
cli_ac_freedata(&tdata);
if(bm_offmode)
cli_bm_freeoff(&toff);
}
if(groot) {
if(ret != CL_VIRUS || SCAN_ALL)
ret = cli_lsig_eval(ctx, groot, &gdata, &info, refhash);
cli_ac_freedata(&gdata);
}
if(info.exeinfo.section)
free(info.exeinfo.section);
cli_hashset_destroy(&info.exeinfo.vinfo);
if (SCAN_ALL && viruses_found)
return CL_VIRUS;
if(ret == CL_VIRUS)
return CL_VIRUS;
return (acmode & AC_SCAN_FT) ? type : CL_CLEAN;
}
