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denyhosts/clamav/libclamav/htmlnorm.c

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添加病毒扫描
2022-10-22 18:41:00 +08:00
/*
* Copyright (C) 2013-2022 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* Copyright (C) 2007-2013 Sourcefire, Inc.
*
* Authors: Trog
*
* Summary: Normalise HTML text. Decode MS Script Encoder protection.
* The ScrEnc decoder was initially based upon an analysis by Andreas Marx.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* 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., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <ctype.h>
#include "clamav.h"
#include "fmap.h"
#include "others.h"
#include "htmlnorm.h"
#include "entconv.h"
#include "jsparse/js-norm.h"
#define HTML_STR_LENGTH 1024
#define MAX_TAG_CONTENTS_LENGTH HTML_STR_LENGTH
typedef enum {
HTML_BAD_STATE,
HTML_NORM,
HTML_8BIT,
HTML_COMMENT,
HTML_CHAR_REF,
HTML_ENTITY_REF_DECODE,
HTML_SKIP_WS,
HTML_TRIM_WS,
HTML_TAG,
HTML_TAG_ARG,
HTML_TAG_ARG_VAL,
HTML_TAG_ARG_EQUAL,
HTML_PROCESS_TAG,
HTML_CHAR_REF_DECODE,
HTML_LOOKFOR_SCRENC,
HTML_JSDECODE,
HTML_JSDECODE_LENGTH,
HTML_JSDECODE_DECRYPT,
HTML_SPECIAL_CHAR,
HTML_RFC2397_TYPE,
HTML_RFC2397_INIT,
HTML_RFC2397_DATA,
HTML_RFC2397_FINISH,
HTML_RFC2397_ESC,
HTML_ESCAPE_CHAR
} html_state;
typedef enum {
SINGLE_QUOTED,
DOUBLE_QUOTED,
NOT_QUOTED
} quoted_state;
#define HTML_FILE_BUFF_LEN 8192
typedef struct file_buff_tag {
int fd;
unsigned char buffer[HTML_FILE_BUFF_LEN];
uint64_t length;
} file_buff_t;
struct tag_contents {
size_t pos;
unsigned char contents[MAX_TAG_CONTENTS_LENGTH + 1];
};
// clang-format off
static const int64_t base64_chars[256] = {
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63,
52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1,-1,-1,-1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14,
15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1,
-1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40,
41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
};
// clang-format on
int table_order[] = {
00, 02, 01, 00, 02, 01, 02, 01, 01, 02, 01, 02, 00, 01, 02, 01,
00, 01, 02, 01, 00, 00, 02, 01, 01, 02, 00, 01, 02, 01, 01, 02,
00, 00, 01, 02, 01, 02, 01, 00, 01, 00, 00, 02, 01, 00, 01, 02,
00, 01, 02, 01, 00, 00, 02, 01, 01, 00, 00, 02, 01, 00, 01, 02};
int decrypt_tables[3][128] = {
{0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x57, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
0x2E, 0x47, 0x7A, 0x56, 0x42, 0x6A, 0x2F, 0x26, 0x49, 0x41, 0x34, 0x32, 0x5B, 0x76, 0x72, 0x43,
0x38, 0x39, 0x70, 0x45, 0x68, 0x71, 0x4F, 0x09, 0x62, 0x44, 0x23, 0x75, 0x3C, 0x7E, 0x3E, 0x5E,
0xFF, 0x77, 0x4A, 0x61, 0x5D, 0x22, 0x4B, 0x6F, 0x4E, 0x3B, 0x4C, 0x50, 0x67, 0x2A, 0x7D, 0x74,
0x54, 0x2B, 0x2D, 0x2C, 0x30, 0x6E, 0x6B, 0x66, 0x35, 0x25, 0x21, 0x64, 0x4D, 0x52, 0x63, 0x3F,
0x7B, 0x78, 0x29, 0x28, 0x73, 0x59, 0x33, 0x7F, 0x6D, 0x55, 0x53, 0x7C, 0x3A, 0x5F, 0x65, 0x46,
0x58, 0x31, 0x69, 0x6C, 0x5A, 0x48, 0x27, 0x5C, 0x3D, 0x24, 0x79, 0x37, 0x60, 0x51, 0x20, 0x36},
{0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x7B, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
0x32, 0x30, 0x21, 0x29, 0x5B, 0x38, 0x33, 0x3D, 0x58, 0x3A, 0x35, 0x65, 0x39, 0x5C, 0x56, 0x73,
0x66, 0x4E, 0x45, 0x6B, 0x62, 0x59, 0x78, 0x5E, 0x7D, 0x4A, 0x6D, 0x71, 0x3C, 0x60, 0x3E, 0x53,
0xFF, 0x42, 0x27, 0x48, 0x72, 0x75, 0x31, 0x37, 0x4D, 0x52, 0x22, 0x54, 0x6A, 0x47, 0x64, 0x2D,
0x20, 0x7F, 0x2E, 0x4C, 0x5D, 0x7E, 0x6C, 0x6F, 0x79, 0x74, 0x43, 0x26, 0x76, 0x25, 0x24, 0x2B,
0x28, 0x23, 0x41, 0x34, 0x09, 0x2A, 0x44, 0x3F, 0x77, 0x3B, 0x55, 0x69, 0x61, 0x63, 0x50, 0x67,
0x51, 0x49, 0x4F, 0x46, 0x68, 0x7C, 0x36, 0x70, 0x6E, 0x7A, 0x2F, 0x5F, 0x4B, 0x5A, 0x2C, 0x57},
{0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x6E, 0x0A, 0x0B, 0x0C, 0x06, 0x0E, 0x0F,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
0x2D, 0x75, 0x52, 0x60, 0x71, 0x5E, 0x49, 0x5C, 0x62, 0x7D, 0x29, 0x36, 0x20, 0x7C, 0x7A, 0x7F,
0x6B, 0x63, 0x33, 0x2B, 0x68, 0x51, 0x66, 0x76, 0x31, 0x64, 0x54, 0x43, 0x3C, 0x3A, 0x3E, 0x7E,
0xFF, 0x45, 0x2C, 0x2A, 0x74, 0x27, 0x37, 0x44, 0x79, 0x59, 0x2F, 0x6F, 0x26, 0x72, 0x6A, 0x39,
0x7B, 0x3F, 0x38, 0x77, 0x67, 0x53, 0x47, 0x34, 0x78, 0x5D, 0x30, 0x23, 0x5A, 0x5B, 0x6C, 0x48,
0x55, 0x70, 0x69, 0x2E, 0x4C, 0x21, 0x24, 0x4E, 0x50, 0x09, 0x56, 0x73, 0x35, 0x61, 0x4B, 0x58,
0x3B, 0x57, 0x22, 0x6D, 0x4D, 0x25, 0x28, 0x46, 0x4A, 0x32, 0x41, 0x3D, 0x5F, 0x4F, 0x42, 0x65}};
static inline unsigned int rewind_tospace(const unsigned char *chunk, unsigned int len)
{
unsigned int count = len;
while (!isspace(chunk[len - 1]) && (len > 1)) {
len--;
}
if (len == 1) {
return count;
}
return len;
}
/* read at most @max_len of data from @m_area or @stream, skipping NULL chars.
* This used to be called cli_readline, but we don't stop at end-of-line anymore */
static unsigned char *cli_readchunk(FILE *stream, m_area_t *m_area, unsigned int max_len)
{
unsigned char *chunk, *start, *ptr, *end;
unsigned int chunk_len, count;
chunk = (unsigned char *)cli_malloc(max_len);
if (!chunk) {
cli_errmsg("readchunk: Unable to allocate memory for chunk\n");
return NULL;
}
/* Try and use the memory buffer first */
if (m_area) {
/* maximum we can copy into the buffer,
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* we could have less than max_len bytes available */
添加病毒扫描
2022-10-22 18:41:00 +08:00
chunk_len = MIN(m_area->length - m_area->offset, max_len - 1);
if (!chunk_len) {
free(chunk);
return NULL;
}
if (m_area->map)
ptr = (unsigned char *)fmap_need_off_once(m_area->map, m_area->offset, chunk_len);
else
ptr = m_area->buffer + m_area->offset;
start = ptr;
end = ptr - m_area->offset + m_area->length;
if ((start >= end) || !start) {
free(chunk);
return NULL;
}
/* look for NULL chars */
ptr = memchr(start, 0, chunk_len);
if (!ptr) {
/* no NULL chars found, copy all */
memcpy(chunk, start, chunk_len);
chunk[chunk_len] = '\0';
m_area->offset += chunk_len;
/* point ptr to end of chunk,
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* so we can check and rewind to a space below */
添加病毒扫描
2022-10-22 18:41:00 +08:00
ptr = start + chunk_len;
} else {
/* copy portion that doesn't contain NULL chars */
chunk_len = ptr - start;
if (chunk_len < max_len) {
memcpy(chunk, start, chunk_len);
} else {
chunk_len = 0;
ptr = start;
}
if (m_area->map)
ptr = (unsigned char *)fmap_need_ptr_once(m_area->map, ptr, end - ptr);
if (!ptr) {
cli_warnmsg("fmap inconsistency\n");
ptr = end;
}
/* we have unknown number of NULL chars,
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* copy char-by-char and skip them */
添加病毒扫描
2022-10-22 18:41:00 +08:00
while ((ptr < end) && (chunk_len < max_len - 1)) {
const unsigned char c = *ptr++;
/* we can't use chunk_len to determine how many bytes we read, since
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* we skipped chars */
添加病毒扫描
2022-10-22 18:41:00 +08:00
if (c) {
chunk[chunk_len++] = c;
}
}
m_area->offset += ptr - start;
chunk[chunk_len] = '\0';
}
if (ptr && ptr < end && !isspace(*ptr)) {
/* we hit max_len, rewind to a space */
count = rewind_tospace(chunk, chunk_len);
if (count < chunk_len) {
chunk[count] = '\0';
m_area->offset -= chunk_len - count;
}
}
} else {
if (!stream) {
cli_dbgmsg("No HTML stream\n");
free(chunk);
return NULL;
}
chunk_len = fread(chunk, 1, max_len - 1, stream);
if (!chunk_len || chunk_len > max_len - 1) {
/* EOF, or prevent overflow */
free(chunk);
return NULL;
}
/* Look for NULL chars */
ptr = memchr(chunk, 0, chunk_len);
if (ptr) {
/* NULL char found */
/* save buffer limits */
start = ptr;
end = chunk + chunk_len;
/* start of NULL chars, we will copy non-NULL characters
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* to this position */
添加病毒扫描
2022-10-22 18:41:00 +08:00
chunk_len = ptr - chunk;
/* find first non-NULL char */
while ((ptr < end) && !(*ptr)) {
ptr++;
}
/* skip over NULL chars, and move back the rest */
while ((ptr < end) && (chunk_len < max_len - 1)) {
const unsigned char c = *ptr++;
if (c) {
chunk[chunk_len++] = c;
}
}
}
chunk[chunk_len] = '\0';
if (chunk_len == max_len - 1) {
/* rewind to a space (which includes newline) */
count = rewind_tospace(chunk, chunk_len);
if (count < chunk_len) {
chunk[count] = '\0';
/* seek-back to space */
fseek(stream, -(long)(chunk_len - count), SEEK_CUR);
}
}
}
return chunk;
}
static void html_output_flush(file_buff_t *fbuff)
{
if (fbuff && (fbuff->length > 0)) {
cli_writen(fbuff->fd, fbuff->buffer, fbuff->length);
fbuff->length = 0;
}
}
static inline void html_output_c(file_buff_t *fbuff1, unsigned char c)
{
if (fbuff1) {
if (fbuff1->length == HTML_FILE_BUFF_LEN) {
html_output_flush(fbuff1);
}
fbuff1->buffer[fbuff1->length++] = c;
}
}
static void html_output_str(file_buff_t *fbuff, const unsigned char *str, size_t len)
{
if (fbuff) {
if ((fbuff->length + len) >= HTML_FILE_BUFF_LEN) {
html_output_flush(fbuff);
}
if (len >= HTML_FILE_BUFF_LEN) {
html_output_flush(fbuff);
cli_writen(fbuff->fd, str, len);
} else {
memcpy(fbuff->buffer + fbuff->length, str, len);
fbuff->length += len;
}
}
}
static char *html_tag_arg_value(tag_arguments_t *tags, const char *tag)
{
int i;
for (i = 0; i < tags->count; i++) {
if (strcmp((const char *)tags->tag[i], tag) == 0) {
return (char *)tags->value[i];
}
}
return NULL;
}
static void html_tag_arg_set(tag_arguments_t *tags, const char *tag, const char *value)
{
int i;
for (i = 0; i < tags->count; i++) {
if (strcmp((const char *)tags->tag[i], tag) == 0) {
free(tags->value[i]);
tags->value[i] = (unsigned char *)cli_strdup(value);
return;
}
}
return;
}
void html_tag_arg_add(tag_arguments_t *tags,
const char *tag, char *value)
{
int len, i;
tags->count++;
tags->tag = (unsigned char **)cli_realloc2(tags->tag,
tags->count * sizeof(char *));
if (!tags->tag) {
goto abort;
}
tags->value = (unsigned char **)cli_realloc2(tags->value,
tags->count * sizeof(char *));
if (!tags->value) {
goto abort;
}
if (tags->scanContents) {
tags->contents = (unsigned char **)cli_realloc2(tags->contents,
tags->count * sizeof(*tags->contents));
if (!tags->contents) {
goto abort;
}
tags->contents[tags->count - 1] = NULL;
}
tags->tag[tags->count - 1] = (unsigned char *)cli_strdup(tag);
if (value) {
if (*value == '"') {
tags->value[tags->count - 1] = (unsigned char *)cli_strdup(value + 1);
len = strlen((const char *)value + 1);
if (len > 0) {
tags->value[tags->count - 1][len - 1] = '\0';
}
} else {
tags->value[tags->count - 1] = (unsigned char *)cli_strdup(value);
}
} else {
tags->value[tags->count - 1] = NULL;
}
return;
abort:
/* Bad error - can't do 100% recovery */
tags->count--;
for (i = 0; i < tags->count; i++) {
if (tags->tag) {
free(tags->tag[i]);
}
if (tags->value) {
free(tags->value[i]);
}
if (tags->contents) {
if (tags->contents[i])
free(tags->contents[i]);
}
}
if (tags->tag) {
free(tags->tag);
}
if (tags->value) {
free(tags->value);
}
if (tags->contents)
free(tags->contents);
tags->contents = NULL;
tags->tag = tags->value = NULL;
tags->count = 0;
return;
}
static void html_output_tag(file_buff_t *fbuff, char *tag, tag_arguments_t *tags)
{
int i, j, len;
html_output_c(fbuff, '<');
html_output_str(fbuff, (const unsigned char *)tag, strlen(tag));
for (i = 0; i < tags->count; i++) {
html_output_c(fbuff, ' ');
html_output_str(fbuff, tags->tag[i], strlen((const char *)tags->tag[i]));
if (tags->value[i]) {
html_output_str(fbuff, (const unsigned char *)"=\"", 2);
len = strlen((const char *)tags->value[i]);
for (j = 0; j < len; j++) {
html_output_c(fbuff, tolower(tags->value[i][j]));
}
html_output_c(fbuff, '"');
}
}
html_output_c(fbuff, '>');
}
void html_tag_arg_free(tag_arguments_t *tags)
{
int i;
for (i = 0; i < tags->count; i++) {
free(tags->tag[i]);
if (tags->value[i]) {
free(tags->value[i]);
}
if (tags->contents)
if (tags->contents[i])
free(tags->contents[i]);
}
if (tags->tag) {
free(tags->tag);
}
if (tags->value) {
free(tags->value);
}
if (tags->contents)
free(tags->contents);
tags->contents = NULL;
tags->tag = tags->value = NULL;
tags->count = 0;
}
/**
* the displayed text for an <a href> tag
*/
static inline void html_tag_contents_append(struct tag_contents *cont, const unsigned char *begin, const unsigned char *end)
{
size_t i;
uint32_t mbchar = 0;
if (!begin || !end)
return;
for (i = cont->pos; i < MAX_TAG_CONTENTS_LENGTH && (begin < end); i++) {
uint8_t c = *begin++;
if (mbchar && (c < 0x80 || mbchar >= 0x10000)) {
if (mbchar == 0xE38082 || mbchar == 0xEFBC8E || mbchar == 0xEFB992 ||
(mbchar == 0xA1 && (c == 0x43 || c == 0x44 || c == 0x4F))) {
cont->contents[i++] = '.';
if (mbchar == 0xA1) {
--i;
mbchar = 0;
continue;
}
} else {
uint8_t c0 = mbchar >> 16;
uint8_t c1 = (mbchar >> 8) & 0xff;
uint8_t c2 = (mbchar & 0xff);
if (c0 && i + 1 < MAX_TAG_CONTENTS_LENGTH)
cont->contents[i++] = c0;
if ((c0 || c1) && i + 1 < MAX_TAG_CONTENTS_LENGTH)
cont->contents[i++] = c1;
if (i + 1 < MAX_TAG_CONTENTS_LENGTH)
cont->contents[i++] = c2;
}
mbchar = 0;
}
if (c >= 0x80) {
mbchar = (mbchar << 8) | c;
--i;
} else
cont->contents[i] = c;
}
cont->pos = i;
}
static inline void html_tag_contents_done(tag_arguments_t *tags, int idx, struct tag_contents *cont)
{
unsigned char *p;
cont->contents[cont->pos++] = '\0';
p = cli_malloc(cont->pos);
if (!p) {
cli_errmsg("html_tag_contents_done: Unable to allocate memory for p\n");
return;
}
memcpy(p, cont->contents, cont->pos);
tags->contents[idx - 1] = p;
cont->pos = 0;
}
struct screnc_state {
uint32_t length;
uint32_t sum;
uint8_t table_pos;
};
/* inplace decoding, so that we can normalize it later */
static void screnc_decode(unsigned char *ptr, struct screnc_state *s)
{
uint8_t value;
unsigned char *dst = ptr;
if (!ptr || !s)
return;
while (s->length > 0 && *ptr) {
if ((*ptr == '\n') || (*ptr == '\r')) {
ptr++;
continue;
}
if (*ptr < 0x80) {
value = decrypt_tables[table_order[s->table_pos]][*ptr];
if (value == 0xFF) { /* special character */
ptr++;
s->length--;
switch (*ptr) {
case '\0':
/* Fixup for end of line */
ptr--;
break;
case 0x21:
value = 0x3c;
break;
case 0x23:
value = 0x0d;
break;
case 0x24:
value = 0x40;
break;
case 0x26:
value = 0x0a;
break;
case 0x2a:
value = 0x3e;
break;
}
}
s->sum += value;
*dst++ = value;
s->table_pos = (s->table_pos + 1) % 64;
} else {
*dst++ = *ptr++;
*dst++ = *ptr;
if (!*ptr) {
dst--;
break;
}
}
ptr++;
s->length--;
}
if (!s->length) {
size_t remaining;
if (strlen((const char *)ptr) >= 12) {
uint64_t expected;
expected = base64_chars[ptr[0]] < 0 ? 0 : base64_chars[ptr[0]] << 2;
expected += base64_chars[ptr[1]] >> 4;
expected += (base64_chars[ptr[1]] & 0x0f) << 12;
expected += ((base64_chars[ptr[2]] >> 2) < 0 ? 0 : (base64_chars[ptr[2]] >> 2)) << 8;
expected += (base64_chars[ptr[2]] & 0x03) << 22;
expected += base64_chars[ptr[3]] < 0 ? 0 : base64_chars[ptr[3]] << 16;
expected += (base64_chars[ptr[4]] < 0 ? 0 : base64_chars[ptr[4]] << 2) << 24;
expected += ((base64_chars[ptr[5]] >> 4) < 0 ? 0 : (base64_chars[ptr[5]] >> 4)) << 24;
ptr += 8;
if (s->sum != expected) {
cli_dbgmsg("screnc_decode: checksum mismatch: %u != %" PRIu64 "\n", s->sum, expected);
} else {
if (strncmp((const char *)ptr, "^#~@", 4) != 0) {
cli_dbgmsg("screnc_decode: terminator not found\n");
} else {
cli_dbgmsg("screnc_decode: OK\n");
}
}
ptr += 4;
}
/* copy remaining */
remaining = strlen((const char *)ptr) + 1;
memmove(dst, ptr, remaining);
} else {
*dst = '\0';
}
}
static void js_process(struct parser_state *js_state, const unsigned char *js_begin, const unsigned char *js_end,
const unsigned char *line, const unsigned char *ptr, int in_script, const char *dirname)
{
if (!js_begin)
js_begin = line;
if (!js_end)
js_end = ptr;
if (js_end > js_begin &&
CLI_ISCONTAINED(line, 8192, js_begin, 1) &&
CLI_ISCONTAINED(line, 8192, js_end, 1)) {
cli_js_process_buffer(js_state, (const char *)js_begin, js_end - js_begin);
}
if (!in_script) {
/* we found a /script, normalize script now */
cli_js_parse_done(js_state);
cli_js_output(js_state, dirname);
cli_js_destroy(js_state);
}
}
static int cli_html_normalise(int fd, m_area_t *m_area, const char *dirname, tag_arguments_t *hrefs, const struct cli_dconf *dconf)
{
int fd_tmp, tag_length = 0, tag_arg_length = 0, binary;
int64_t retval = FALSE, escape = FALSE, value = 0, hex = FALSE, tag_val_length = 0;
int look_for_screnc = FALSE, in_screnc = FALSE, in_script = FALSE, text_space_written = FALSE;
FILE *stream_in = NULL;
html_state state = HTML_NORM, next_state = HTML_BAD_STATE, saved_next_state = HTML_BAD_STATE;
char filename[1024], tag[HTML_STR_LENGTH + 1], tag_arg[HTML_STR_LENGTH + 1];
char tag_val[HTML_STR_LENGTH + 1], *tmp_file, *arg_value;
unsigned char *line = NULL, *ptr, *ptr_screnc = NULL;
tag_arguments_t tag_args;
quoted_state quoted = NOT_QUOTED;
unsigned long length = 0;
struct screnc_state screnc_state;
file_buff_t *file_buff_o2, *file_buff_text;
file_buff_t *file_tmp_o1 = NULL;
int in_ahref = 0; /* index of <a> tag, whose contents we are parsing. Indexing starts from 1, 0 means outside of <a>*/
unsigned char *href_contents_begin = NULL; /*beginning of the next portion of <a> contents*/
unsigned char *ptrend = NULL; /*end of <a> contents*/
unsigned char *in_form_action = NULL; /* the action URL of the current <form> tag, if any*/
struct entity_conv conv;
unsigned char entity_val[HTML_STR_LENGTH + 1];
size_t entity_val_length = 0;
const int dconf_entconv = dconf ? dconf->phishing & PHISHING_CONF_ENTCONV : 1;
const int dconf_js = dirname && (dconf ? dconf->doc & DOC_CONF_JSNORM : 1); /* TODO */
/* dconf for phishing engine sets scanContents, so no need for a flag here */
struct parser_state *js_state = NULL;
const unsigned char *js_begin = NULL, *js_end = NULL;
struct tag_contents contents;
uint32_t mbchar = 0;
uint32_t mbchar2 = 0;
/*
* Initialize stack buffers.
*/
memset(filename, 0, sizeof(filename));
memset(tag, 0, sizeof(tag));
memset(tag_arg, 0, sizeof(tag_arg));
memset(tag_val, 0, sizeof(tag_val));
memset(entity_val, 0, sizeof(entity_val));
tag_args.scanContents = 0; /* do we need to store the contents of <a></a>?*/
contents.pos = 0;
if (!m_area) {
if (fd < 0) {
cli_dbgmsg("Invalid HTML fd\n");
return FALSE;
}
lseek(fd, 0, SEEK_SET);
fd_tmp = dup(fd);
if (fd_tmp < 0) {
return FALSE;
}
stream_in = fdopen(fd_tmp, "r");
if (!stream_in) {
close(fd_tmp);
return FALSE;
}
}
tag_args.count = 0;
tag_args.tag = NULL;
tag_args.value = NULL;
tag_args.contents = NULL;
if (dirname) {
file_buff_o2 = (file_buff_t *)cli_malloc(sizeof(file_buff_t));
if (!file_buff_o2) {
cli_errmsg("cli_html_normalise: Unable to allocate memory for file_buff_o2\n");
file_buff_o2 = file_buff_text = NULL;
goto abort;
}
/* this will still contains scripts that are inside comments */
snprintf(filename, 1024, "%s" PATHSEP "nocomment.html", dirname);
更新libclamav库1.0.0版本
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file_buff_o2->fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IWUSR | S_IRUSR);
添加病毒扫描
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if (file_buff_o2->fd == -1) {
cli_dbgmsg("open failed: %s\n", filename);
free(file_buff_o2);
file_buff_o2 = file_buff_text = NULL;
goto abort;
}
file_buff_text = (file_buff_t *)cli_malloc(sizeof(file_buff_t));
if (!file_buff_text) {
close(file_buff_o2->fd);
free(file_buff_o2);
file_buff_o2 = file_buff_text = NULL;
cli_errmsg("cli_html_normalise: Unable to allocate memory for file_buff_text\n");
goto abort;
}
snprintf(filename, 1024, "%s" PATHSEP "notags.html", dirname);
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
file_buff_text->fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IWUSR | S_IRUSR);
添加病毒扫描
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if (file_buff_text->fd == -1) {
cli_dbgmsg("open failed: %s\n", filename);
close(file_buff_o2->fd);
free(file_buff_o2);
free(file_buff_text);
file_buff_o2 = file_buff_text = NULL;
goto abort;
}
file_buff_o2->length = 0;
file_buff_text->length = 0;
} else {
file_buff_o2 = NULL;
file_buff_text = NULL;
}
binary = FALSE;
ptr = line = cli_readchunk(stream_in, m_area, 8192);
while (line) {
if (href_contents_begin)
href_contents_begin = ptr; /*start of a new line, last line already appended to contents see below*/
while (*ptr && isspace(*ptr)) {
ptr++;
}
while (*ptr) {
if (!binary && *ptr == '\n') {
/* Convert it to a space and re-process */
*ptr = ' ';
continue;
}
if (!binary && *ptr == '\r') {
ptr++;
continue;
}
switch (state) {
case HTML_SPECIAL_CHAR:
cli_dbgmsg("Impossible, special_char can't occur here\n");
break;
case HTML_BAD_STATE:
/* An engine error has occurred */
cli_dbgmsg("HTML Engine Error\n");
goto abort;
case HTML_SKIP_WS:
if (isspace(*ptr)) {
ptr++;
} else {
state = next_state;
next_state = HTML_BAD_STATE;
}
break;
case HTML_TRIM_WS:
if (isspace(*ptr)) {
ptr++;
} else {
if (!in_script)
html_output_c(file_buff_o2, ' ');
state = next_state;
next_state = HTML_BAD_STATE;
}
break;
case HTML_8BIT:
if (*ptr < 0x80 || mbchar >= 0x10000) {
if (mbchar == 0xE38082 || mbchar == 0xEFBC8E || mbchar == 0xEFB992 ||
(mbchar == 0xA1 && (*ptr == 0x43 || *ptr == 0x44 || *ptr == 0x4F))) {
/* bb #4097 */
html_output_c(file_buff_o2, '.');
html_output_c(file_buff_text, '.');
if (mbchar == 0xA1) {
ptr++;
mbchar = 0;
continue;
}
} else {
uint8_t c0 = mbchar >> 16;
uint8_t c1 = (mbchar >> 8) & 0xff;
uint8_t c2 = (mbchar & 0xff);
if (c0) {
html_output_c(file_buff_o2, c0);
html_output_c(file_buff_text, c0);
}
if (c0 || c1) {
html_output_c(file_buff_o2, c1);
html_output_c(file_buff_text, c1);
}
html_output_c(file_buff_o2, c2);
html_output_c(file_buff_text, c1);
}
mbchar = 0;
state = next_state;
next_state = HTML_NORM;
} else {
mbchar = (mbchar << 8) | *ptr;
ptr++;
}
break;
case HTML_NORM:
if (*ptr == '<') {
ptrend = ptr; /* for use by scanContents */
html_output_c(file_buff_o2, '<');
if (!in_script && !text_space_written) {
html_output_c(file_buff_text, ' ');
text_space_written = TRUE;
}
if (hrefs && hrefs->scanContents && in_ahref && href_contents_begin) {
/*append this text portion to the contents of <a>*/
html_tag_contents_append(&contents, href_contents_begin, ptr);
href_contents_begin = NULL; /*We just encountered another tag inside <a>, so skip it*/
}
ptr++;
state = HTML_SKIP_WS;
tag_length = 0;
next_state = HTML_TAG;
} else if (isspace(*ptr)) {
if (!text_space_written && !in_script) {
html_output_c(file_buff_text, ' ');
text_space_written = TRUE;
}
state = HTML_TRIM_WS;
next_state = HTML_NORM;
} else if (*ptr == '&') {
if (!text_space_written && !in_script) {
html_output_c(file_buff_text, ' ');
text_space_written = TRUE;
}
state = HTML_CHAR_REF;
next_state = HTML_NORM;
ptr++;
} else if (*ptr >= 0x80) {
state = HTML_8BIT;
next_state = HTML_NORM;
mbchar = *ptr;
ptr++;
} else {
unsigned char c = tolower(*ptr);
/* normalize ' to " for scripts */
if (in_script && c == '\'') c = '"';
html_output_c(file_buff_o2, c);
if (!in_script) {
if (*ptr < 0x20) {
if (!text_space_written) {
html_output_c(file_buff_text, ' ');
text_space_written = TRUE;
}
} else {
html_output_c(file_buff_text, c);
text_space_written = FALSE;
}
}
ptr++;
}
break;
case HTML_TAG:
if ((tag_length == 0) && (*ptr == '!')) {
/* Comment */
if (in_script) {
/* we still write scripts to nocomment.html */
html_output_c(file_buff_o2, '!');
} else {
/* Need to rewind in the no-comment output stream */
if (file_buff_o2 && (file_buff_o2->length > 0)) {
file_buff_o2->length--;
}
}
state = HTML_COMMENT;
next_state = HTML_BAD_STATE;
ptr++;
} else if (*ptr == '>') {
html_output_c(file_buff_o2, '>');
ptr++;
tag[tag_length] = '\0';
state = HTML_SKIP_WS;
next_state = HTML_PROCESS_TAG;
} else if (!isspace(*ptr)) {
html_output_c(file_buff_o2, tolower(*ptr));
/* if we're inside a script we only care for </script>.*/
if (in_script && tag_length == 0 && *ptr != '/') {
state = HTML_NORM;
}
if (tag_length < HTML_STR_LENGTH) {
tag[tag_length++] = tolower(*ptr);
}
ptr++;
} else {
tag[tag_length] = '\0';
state = HTML_SKIP_WS;
tag_arg_length = 0;
/* if we'd go to HTML_TAG_ARG whitespace would be inconsistently normalized for in_script*/
next_state = !in_script ? HTML_TAG_ARG : HTML_PROCESS_TAG;
}
break;
case HTML_TAG_ARG:
if (*ptr == '=') {
html_output_c(file_buff_o2, '=');
tag_arg[tag_arg_length] = '\0';
ptr++;
state = HTML_SKIP_WS;
escape = FALSE;
quoted = NOT_QUOTED;
tag_val_length = 0;
next_state = HTML_TAG_ARG_VAL;
} else if (isspace(*ptr)) {
ptr++;
tag_arg[tag_arg_length] = '\0';
state = HTML_SKIP_WS;
next_state = HTML_TAG_ARG_EQUAL;
} else if (*ptr == '>') {
html_output_c(file_buff_o2, '>');
if (tag_arg_length > 0) {
tag_arg[tag_arg_length] = '\0';
html_tag_arg_add(&tag_args, tag_arg, NULL);
}
ptr++;
state = HTML_PROCESS_TAG;
next_state = HTML_BAD_STATE;
} else {
if (tag_arg_length == 0) {
/* Start of new tag - add space */
html_output_c(file_buff_o2, ' ');
}
html_output_c(file_buff_o2, tolower(*ptr));
if (tag_arg_length < HTML_STR_LENGTH) {
tag_arg[tag_arg_length++] = tolower(*ptr);
}
ptr++;
}
break;
case HTML_TAG_ARG_EQUAL:
if (*ptr == '=') {
html_output_c(file_buff_o2, '=');
ptr++;
state = HTML_SKIP_WS;
escape = FALSE;
quoted = NOT_QUOTED;
tag_val_length = 0;
next_state = HTML_TAG_ARG_VAL;
} else {
if (tag_arg_length > 0) {
tag_arg[tag_arg_length] = '\0';
html_tag_arg_add(&tag_args, tag_arg, NULL);
}
tag_arg_length = 0;
state = HTML_TAG_ARG;
next_state = HTML_BAD_STATE;
}
break;
case HTML_TAG_ARG_VAL:
if ((tag_val_length == 5) && (strncmp(tag_val, "data:", 5) == 0)) {
/* RFC2397 inline data */
/* Rewind one byte so we don't recursive */
if (file_buff_o2 && (file_buff_o2->length > 0)) {
file_buff_o2->length--;
}
if (quoted != NOT_QUOTED) {
html_output_c(file_buff_o2, '"');
}
tag_val_length = 0;
state = HTML_RFC2397_TYPE;
next_state = HTML_TAG_ARG;
} else if ((tag_val_length == 6) && (strncmp(tag_val, "\"data:", 6) == 0)) {
/* RFC2397 inline data */
/* Rewind one byte so we don't recursive */
if (file_buff_o2 && (file_buff_o2->length > 0)) {
file_buff_o2->length--;
}
if (quoted != NOT_QUOTED) {
html_output_c(file_buff_o2, '"');
}
tag_val_length = 0;
state = HTML_RFC2397_TYPE;
next_state = HTML_TAG_ARG;
} else if (*ptr == '&') {
state = HTML_CHAR_REF;
next_state = HTML_TAG_ARG_VAL;
ptr++;
} else if (*ptr == '\'') {
if (tag_val_length == 0) {
quoted = SINGLE_QUOTED;
html_output_c(file_buff_o2, '"');
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
ptr++;
} else {
if (!escape && (quoted == SINGLE_QUOTED)) {
html_output_c(file_buff_o2, '"');
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
tag_val[tag_val_length] = '\0';
html_tag_arg_add(&tag_args, tag_arg, tag_val);
ptr++;
state = HTML_SKIP_WS;
tag_arg_length = 0;
next_state = HTML_TAG_ARG;
} else {
html_output_c(file_buff_o2, '"');
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
ptr++;
}
}
} else if (*ptr == '"') {
if (tag_val_length == 0) {
quoted = DOUBLE_QUOTED;
html_output_c(file_buff_o2, '"');
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
ptr++;
} else {
if (!escape && (quoted == DOUBLE_QUOTED)) {
html_output_c(file_buff_o2, '"');
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
tag_val[tag_val_length] = '\0';
html_tag_arg_add(&tag_args, tag_arg, tag_val);
ptr++;
state = HTML_SKIP_WS;
tag_arg_length = 0;
next_state = HTML_TAG_ARG;
} else {
html_output_c(file_buff_o2, '"');
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
ptr++;
}
}
} else if (isspace(*ptr) || (*ptr == '>')) {
if (quoted == NOT_QUOTED) {
tag_val[tag_val_length] = '\0';
html_tag_arg_add(&tag_args, tag_arg, tag_val);
state = HTML_SKIP_WS;
tag_arg_length = 0;
next_state = HTML_TAG_ARG;
} else {
html_output_c(file_buff_o2, *ptr);
if (tag_val_length < HTML_STR_LENGTH) {
if (isspace(*ptr)) {
tag_val[tag_val_length++] = ' ';
} else {
tag_val[tag_val_length++] = '>';
}
}
state = HTML_SKIP_WS;
escape = FALSE;
quoted = NOT_QUOTED;
next_state = HTML_TAG_ARG_VAL;
ptr++;
}
} else {
if (mbchar2 && (*ptr < 0x80 || mbchar2 >= 0x10000)) {
if (mbchar2 == 0xE38082 || mbchar2 == 0xEFBC8E || mbchar2 == 0xEFB992 ||
(mbchar2 == 0xA1 && (*ptr == 0x43 || *ptr == 0x44 || *ptr == 0x4F))) {
html_output_c(file_buff_o2, '.');
if (tag_val_length < HTML_STR_LENGTH)
tag_val[tag_val_length++] = '.';
if (mbchar2 == 0xA1) {
ptr++;
mbchar2 = 0;
continue;
}
} else {
uint8_t c0 = mbchar2 >> 16;
uint8_t c1 = (mbchar2 >> 8) & 0xff;
uint8_t c2 = (mbchar2 & 0xff);
if (c0)
html_output_c(file_buff_o2, c0);
if (c0 || c1)
html_output_c(file_buff_o2, c1);
html_output_c(file_buff_o2, c2);
if (c0 && tag_val_length < HTML_STR_LENGTH)
tag_val[tag_val_length++] = c0;
if ((c0 || c1) && tag_val_length < HTML_STR_LENGTH)
tag_val[tag_val_length++] = c1;
if (tag_val_length < HTML_STR_LENGTH)
tag_val[tag_val_length++] = c2;
}
mbchar2 = 0;
}
if (*ptr >= 0x80)
mbchar2 = (mbchar2 << 8) | *ptr;
else {
html_output_c(file_buff_o2, tolower(*ptr));
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = *ptr;
}
}
ptr++;
}
if (*ptr == '\\') {
escape = TRUE;
} else {
escape = FALSE;
}
break;
case HTML_COMMENT:
if (in_script && !isspace(*ptr)) {
unsigned char c = tolower(*ptr);
/* dump script to nocomment.html, since we no longer have
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* comment.html/script.html */
添加病毒扫描
2022-10-22 18:41:00 +08:00
if (c == '\'') c = '"';
html_output_c(file_buff_o2, c);
}
if (*ptr == '>') {
state = HTML_SKIP_WS;
next_state = HTML_NORM;
}
ptr++;
break;
case HTML_PROCESS_TAG:
/* Default to no action for this tag */
state = HTML_SKIP_WS;
next_state = HTML_NORM;
if (tag[0] == '/') {
/* End tag */
state = HTML_SKIP_WS;
next_state = HTML_NORM;
if (strcmp(tag, "/script") == 0) {
in_script = FALSE;
if (js_state) {
js_end = ptr;
js_process(js_state, js_begin, js_end, line, ptr, in_script, dirname);
js_state = NULL;
js_begin = js_end = NULL;
}
/*don't output newlines in nocomment.html
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
* html_output_c(file_buff_o2, '\n');*/
添加病毒扫描
2022-10-22 18:41:00 +08:00
}
if (hrefs && hrefs->scanContents && in_ahref) {
if (strcmp(tag, "/a") == 0) {
html_tag_contents_done(hrefs, in_ahref, &contents);
in_ahref = 0; /* we are no longer inside an <a href>
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
nesting <a> tags not supported, and shouldn't be supported*/
添加病毒扫描
2022-10-22 18:41:00 +08:00
}
href_contents_begin = ptr;
}
if (strcmp(tag, "/form") == 0) {
if (in_form_action)
free(in_form_action);
in_form_action = NULL;
}
} else if (strcmp(tag, "script") == 0) {
arg_value = html_tag_arg_value(&tag_args, "language");
/* TODO: maybe we can output all tags only via html_output_tag */
if (arg_value && (strcasecmp((const char *)arg_value, "jscript.encode") == 0)) {
html_tag_arg_set(&tag_args, "language", "javascript");
state = HTML_SKIP_WS;
next_state = HTML_JSDECODE;
/* we already output the old tag, output the new tag now */
html_output_tag(file_buff_o2, tag, &tag_args);
} else if (arg_value && (strcasecmp((const char *)arg_value, "vbscript.encode") == 0)) {
html_tag_arg_set(&tag_args, "language", "vbscript");
state = HTML_SKIP_WS;
next_state = HTML_JSDECODE;
/* we already output the old tag, output the new tag now */
html_output_tag(file_buff_o2, tag, &tag_args);
}
in_script = TRUE;
if (dconf_js && !js_state) {
js_state = cli_js_init();
if (!js_state) {
cli_dbgmsg("htmlnorm: Failed to initialize js parser\n");
}
js_begin = ptr;
js_end = NULL;
}
} else if (strcmp(tag, "%@") == 0) {
arg_value = html_tag_arg_value(&tag_args, "language");
if (arg_value && (strcasecmp((const char *)arg_value, "jscript.encode") == 0 ||
strcasecmp((const char *)arg_value, "vbscript.encode") == 0)) {
saved_next_state = next_state;
next_state = state;
look_for_screnc = FALSE;
state = HTML_LOOKFOR_SCRENC;
}
} else if (hrefs) {
if (in_ahref && !href_contents_begin)
href_contents_begin = ptr;
if (strcmp(tag, "a") == 0) {
arg_value = html_tag_arg_value(&tag_args, "href");
if (arg_value && strlen((const char *)arg_value) > 0) {
if (hrefs->scanContents) {
char *arg_value_title = html_tag_arg_value(&tag_args, "title");
/*beginning of an <a> tag*/
if (in_ahref)
/*we encountered nested <a> tags, pretend previous closed*/
if (href_contents_begin) {
html_tag_contents_append(&contents, href_contents_begin, ptrend);
/*add pending contents between tags*/
html_tag_contents_done(hrefs, in_ahref, &contents);
in_ahref = 0;
}
if (arg_value_title) {
/* title is a 'displayed link'*/
html_tag_arg_add(hrefs, "href_title", arg_value_title);
html_tag_contents_append(&contents, (const unsigned char *)arg_value,
(const unsigned char *)arg_value + strlen(arg_value));
html_tag_contents_done(hrefs, hrefs->count, &contents);
}
if (in_form_action) {
/* form action is the real URL, and href is the 'displayed' */
html_tag_arg_add(hrefs, "form", arg_value);
contents.pos = 0;
html_tag_contents_append(&contents, in_form_action,
in_form_action + strlen((const char *)in_form_action));
html_tag_contents_done(hrefs, hrefs->count, &contents);
}
}
html_tag_arg_add(hrefs, "href", arg_value);
if (hrefs->scanContents) {
in_ahref = hrefs->count; /* index of this tag (counted from 1) */
href_contents_begin = ptr; /* contents begin after <a ..> ends */
contents.pos = 0;
}
}
} else if (strcmp(tag, "form") == 0 && hrefs->scanContents) {
const char *arg_action_value = html_tag_arg_value(&tag_args, "action");
if (arg_action_value) {
if (in_form_action)
free(in_form_action);
in_form_action = (unsigned char *)cli_strdup(arg_action_value);
}
} else if (strcmp(tag, "img") == 0) {
arg_value = html_tag_arg_value(&tag_args, "src");
if (arg_value && strlen(arg_value) > 0) {
html_tag_arg_add(hrefs, "src", arg_value);
if (hrefs->scanContents && in_ahref)
/* "contents" of an img tag, is the URL of its parent <a> tag */
hrefs->contents[hrefs->count - 1] = (unsigned char *)cli_strdup((const char *)hrefs->value[in_ahref - 1]);
if (in_form_action) {
/* form action is the real URL, and href is the 'displayed' */
html_tag_arg_add(hrefs, "form", arg_value);
contents.pos = 0;
html_tag_contents_append(&contents, in_form_action,
in_form_action + strlen((const char *)in_form_action));
html_tag_contents_done(hrefs, hrefs->count, &contents);
}
}
arg_value = html_tag_arg_value(&tag_args, "dynsrc");
if (arg_value && strlen(arg_value) > 0) {
html_tag_arg_add(hrefs, "dynsrc", arg_value);
if (hrefs->scanContents && in_ahref)
/* see above */
hrefs->contents[hrefs->count - 1] = (unsigned char *)cli_strdup((const char *)hrefs->value[in_ahref - 1]);
if (in_form_action) {
/* form action is the real URL, and href is the 'displayed' */
html_tag_arg_add(hrefs, "form", arg_value);
contents.pos = 0;
html_tag_contents_append(&contents, in_form_action,
in_form_action + strlen((const char *)in_form_action));
html_tag_contents_done(hrefs, hrefs->count, &contents);
}
}
} else if (strcmp(tag, "iframe") == 0) {
arg_value = html_tag_arg_value(&tag_args, "src");
if (arg_value && strlen(arg_value) > 0) {
html_tag_arg_add(hrefs, "iframe", arg_value);
if (hrefs->scanContents && in_ahref)
/* see above */
hrefs->contents[hrefs->count - 1] = (unsigned char *)cli_strdup((const char *)hrefs->value[in_ahref - 1]);
if (in_form_action) {
/* form action is the real URL, and href is the 'displayed' */
html_tag_arg_add(hrefs, "form", arg_value);
contents.pos = 0;
html_tag_contents_append(&contents, in_form_action,
in_form_action + strlen((const char *)in_form_action));
html_tag_contents_done(hrefs, hrefs->count, &contents);
}
}
} else if (strcmp(tag, "area") == 0) {
arg_value = html_tag_arg_value(&tag_args, "href");
if (arg_value && strlen(arg_value) > 0) {
html_tag_arg_add(hrefs, "area", arg_value);
if (hrefs->scanContents && in_ahref)
/* see above */
hrefs->contents[hrefs->count - 1] = (unsigned char *)cli_strdup((const char *)hrefs->value[in_ahref - 1]);
if (in_form_action) {
/* form action is the real URL, and href is the 'displayed' */
html_tag_arg_add(hrefs, "form", arg_value);
contents.pos = 0;
html_tag_contents_append(&contents, in_form_action,
in_form_action + strlen((const char *)in_form_action));
html_tag_contents_done(hrefs, hrefs->count, &contents);
}
}
}
/* TODO:imagemaps can have urls too */
} else if (strcmp(tag, "a") == 0) {
/* a/img tags for buff_text can be processed only if we're not processing hrefs */
arg_value = html_tag_arg_value(&tag_args, "href");
if (arg_value && arg_value[0]) {
html_output_str(file_buff_text, (const unsigned char *)arg_value, strlen((const char *)arg_value));
html_output_c(file_buff_text, ' ');
text_space_written = TRUE;
}
} else if (strcmp(tag, "img") == 0) {
arg_value = html_tag_arg_value(&tag_args, "src");
if (arg_value && arg_value[0]) {
html_output_str(file_buff_text, (const unsigned char *)arg_value, strlen((const char *)arg_value));
html_output_c(file_buff_text, ' ');
text_space_written = TRUE;
}
}
html_tag_arg_free(&tag_args);
break;
case HTML_CHAR_REF:
if (*ptr == '#') {
value = 0;
hex = FALSE;
state = HTML_CHAR_REF_DECODE;
ptr++;
} else {
if (dconf_entconv)
state = HTML_ENTITY_REF_DECODE;
else {
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '&';
}
html_output_c(file_buff_o2, '&');
state = next_state;
next_state = HTML_BAD_STATE;
}
}
break;
case HTML_ENTITY_REF_DECODE:
if (*ptr == ';') {
size_t i;
const char *normalized;
entity_val[entity_val_length] = '\0';
normalized = entity_norm(&conv, entity_val);
if (normalized) {
for (i = 0; i < strlen(normalized); i++) {
const unsigned char c = normalized[i] & 0xff;
html_output_c(file_buff_o2, c);
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = c;
}
}
} else {
html_output_c(file_buff_o2, '&');
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '&';
}
for (i = 0; i < entity_val_length; i++) {
const char c = tolower(entity_val[i]);
html_output_c(file_buff_o2, c);
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = c;
}
}
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = ';';
}
html_output_c(file_buff_o2, ';');
}
entity_val_length = 0;
state = next_state;
next_state = HTML_BAD_STATE;
ptr++;
} else if ((isalnum(*ptr) || *ptr == '_' || *ptr == ':' || (*ptr == '-')) && entity_val_length < HTML_STR_LENGTH) {
entity_val[entity_val_length++] = *ptr++;
} else {
/* entity too long, or not valid, dump it */
size_t i;
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '&';
}
html_output_c(file_buff_o2, '&');
for (i = 0; i < entity_val_length; i++) {
const char c = tolower(entity_val[i]);
html_output_c(file_buff_o2, c);
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = c;
}
}
state = next_state;
next_state = HTML_BAD_STATE;
entity_val_length = 0;
}
break;
case HTML_CHAR_REF_DECODE:
if ((value == 0) && ((*ptr == 'x') || (*ptr == 'X'))) {
hex = TRUE;
ptr++;
} else if (*ptr == ';') {
if (next_state == HTML_TAG_ARG_VAL && tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = value; /* store encoded values too */
}
if (dconf_entconv) {
if (value < 0x80)
html_output_c(file_buff_o2, tolower(value));
else {
unsigned char buff[10];
unsigned char *out = u16_normalize_tobuffer(value, buff, 10);
if (out && out > buff) {
html_output_str(file_buff_o2, buff, out - buff - 1);
}
}
} else
html_output_c(file_buff_o2, tolower(value & 0xff));
state = next_state;
next_state = HTML_BAD_STATE;
ptr++;
} else if (isdigit(*ptr) || (hex && isxdigit(*ptr))) {
int64_t increment = 0;
if (hex && value < INT64_MAX / 16) {
value *= 16;
} else if (value < INT64_MAX / 10) {
value *= 10;
} else {
html_output_c(file_buff_o2, value);
state = next_state;
next_state = HTML_BAD_STATE;
ptr++;
break;
}
if (isdigit(*ptr)) {
increment = *ptr - '0';
} else {
increment = tolower(*ptr) - 'a' + 10;
}
if (value > INT64_MAX - increment) {
/* Addition would result in integer overflow. */
html_output_c(file_buff_o2, value);
state = next_state;
next_state = HTML_BAD_STATE;
ptr++;
break;
}
value += increment;
ptr++;
} else {
html_output_c(file_buff_o2, value);
state = next_state;
next_state = HTML_BAD_STATE;
}
break;
case HTML_LOOKFOR_SCRENC:
look_for_screnc = TRUE;
ptr_screnc = (unsigned char *)strstr((char *)ptr, "#@~^");
if (ptr_screnc) {
ptr_screnc[0] = '/';
ptr_screnc[1] = '/';
ptr_screnc += 4;
}
state = next_state;
next_state = saved_next_state;
break;
case HTML_JSDECODE:
/* Check for start marker */
if (strncmp((const char *)ptr, "#@~^", 4) == 0) {
ptr[0] = '/';
ptr[1] = '/';
ptr += 4;
state = HTML_JSDECODE_LENGTH;
next_state = HTML_BAD_STATE;
} else {
html_output_c(file_buff_o2, tolower(*ptr));
ptr++;
}
break;
case HTML_JSDECODE_LENGTH:
if (strlen((const char *)ptr) < 8) {
state = HTML_NORM;
next_state = HTML_BAD_STATE;
break;
}
memset(&screnc_state, 0, sizeof(screnc_state));
screnc_state.length = base64_chars[ptr[0]] < 0 ? 0 : base64_chars[ptr[0]] << 2;
screnc_state.length += base64_chars[ptr[1]] >> 4;
screnc_state.length += (base64_chars[ptr[1]] & 0x0f) << 12;
screnc_state.length += ((base64_chars[ptr[2]] >> 2) < 0 ? 0 : (base64_chars[ptr[2]] >> 2)) << 8;
screnc_state.length += (base64_chars[ptr[2]] & 0x03) << 22;
screnc_state.length += base64_chars[ptr[3]] < 0 ? 0 : base64_chars[ptr[3]] << 16;
screnc_state.length += (base64_chars[ptr[4]] < 0 ? 0 : base64_chars[ptr[4]] << 2) << 24;
screnc_state.length += ((base64_chars[ptr[5]] >> 4) < 0 ? 0 : (base64_chars[ptr[5]] >> 4)) << 24;
state = HTML_JSDECODE_DECRYPT;
in_screnc = TRUE;
next_state = HTML_BAD_STATE;
/* for JS normalizer */
ptr[7] = '\n';
ptr += 8;
break;
case HTML_JSDECODE_DECRYPT:
screnc_decode(ptr, &screnc_state);
if (!screnc_state.length) {
state = HTML_NORM;
next_state = HTML_BAD_STATE;
in_screnc = FALSE;
break;
} else {
state = HTML_NORM;
next_state = HTML_BAD_STATE;
}
break;
case HTML_RFC2397_TYPE:
if (*ptr == '\'') {
if (!escape && (quoted == SINGLE_QUOTED)) {
/* Early end of data detected. Error */
ptr++;
state = HTML_SKIP_WS;
tag_arg_length = 0;
next_state = HTML_TAG_ARG;
} else {
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
ptr++;
}
} else if (*ptr == '"') {
if (!escape && (quoted == DOUBLE_QUOTED)) {
/* Early end of data detected. Error */
ptr++;
state = HTML_SKIP_WS;
tag_arg_length = 0;
next_state = HTML_TAG_ARG;
} else {
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = '"';
}
ptr++;
}
} else if (isspace(*ptr) || (*ptr == '>')) {
if (quoted == NOT_QUOTED) {
/* Early end of data detected. Error */
state = HTML_SKIP_WS;
tag_arg_length = 0;
next_state = HTML_TAG_ARG;
} else {
if (tag_val_length < HTML_STR_LENGTH) {
if (isspace(*ptr)) {
tag_val[tag_val_length++] = ' ';
} else {
tag_val[tag_val_length++] = '>';
}
}
state = HTML_SKIP_WS;
escape = FALSE;
quoted = NOT_QUOTED;
next_state = HTML_RFC2397_TYPE;
ptr++;
}
} else if (*ptr == ',') {
/* Beginning of data */
tag_val[tag_val_length] = '\0';
state = HTML_RFC2397_INIT;
escape = FALSE;
next_state = HTML_BAD_STATE;
ptr++;
} else {
if (tag_val_length < HTML_STR_LENGTH) {
tag_val[tag_val_length++] = tolower(*ptr);
}
ptr++;
}
if (*ptr == '\\') {
escape = TRUE;
} else {
escape = FALSE;
}
break;
case HTML_RFC2397_INIT:
if (dirname) {
STATBUF statbuf;
if (NULL != file_tmp_o1) {
if (file_tmp_o1->fd != -1) {
html_output_flush(file_tmp_o1);
close(file_tmp_o1->fd);
file_tmp_o1->fd = -1;
}
free(file_tmp_o1);
}
file_tmp_o1 = (file_buff_t *)cli_malloc(sizeof(file_buff_t));
if (!file_tmp_o1) {
cli_errmsg("cli_html_normalise: Unable to allocate memory for file_tmp_o1\n");
goto abort;
}
file_tmp_o1->fd = -1;
/* Create rfc2397 directory if it doesn't already exist */
snprintf(filename, 1024, "%s" PATHSEP "rfc2397", dirname);
if (LSTAT(filename, &statbuf) == -1) {
if (mkdir(filename, 0700) && errno != EEXIST) {
cli_errmsg("Failed to create directory: %s\n", dirname);
goto abort;
}
}
tmp_file = cli_gentemp(filename);
if (!tmp_file) {
goto abort;
}
cli_dbgmsg("RFC2397 data file: %s\n", tmp_file);
更新libclamav库1.0.0版本
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file_tmp_o1->fd = open(tmp_file, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IWUSR | S_IRUSR);
添加病毒扫描
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free(tmp_file);
if (file_tmp_o1->fd < 0) {
cli_dbgmsg("open failed: %s\n", filename);
goto abort;
}
file_tmp_o1->length = 0;
html_output_str(file_tmp_o1, (const unsigned char *)"From html-normalise\n", 20);
html_output_str(file_tmp_o1, (const unsigned char *)"Content-type: ", 14);
if ((tag_val_length == 0) && (*tag_val == ';')) {
html_output_str(file_tmp_o1, (const unsigned char *)"text/plain\n", 11);
}
html_output_str(file_tmp_o1, (const unsigned char *)tag_val, tag_val_length);
html_output_c(file_tmp_o1, '\n');
if (strstr(tag_val, ";base64") != NULL) {
html_output_str(file_tmp_o1, (const unsigned char *)"Content-transfer-encoding: base64\n", 34);
}
html_output_c(file_tmp_o1, '\n');
} else {
file_tmp_o1 = NULL;
}
state = HTML_RFC2397_DATA;
binary = TRUE;
break;
case HTML_RFC2397_DATA:
if (*ptr == '&') {
state = HTML_CHAR_REF;
next_state = HTML_RFC2397_DATA;
ptr++;
} else if (*ptr == '%') {
length = 0;
value = 0;
state = HTML_ESCAPE_CHAR;
next_state = HTML_RFC2397_ESC;
ptr++;
} else if (*ptr == '\'') {
if (!escape && (quoted == SINGLE_QUOTED)) {
state = HTML_RFC2397_FINISH;
ptr++;
} else {
html_output_c(file_tmp_o1, *ptr);
ptr++;
}
} else if (*ptr == '\"') {
if (!escape && (quoted == DOUBLE_QUOTED)) {
state = HTML_RFC2397_FINISH;
ptr++;
} else {
html_output_c(file_tmp_o1, *ptr);
ptr++;
}
} else if (isspace(*ptr) || (*ptr == '>')) {
if (quoted == NOT_QUOTED) {
state = HTML_RFC2397_FINISH;
ptr++;
} else {
html_output_c(file_tmp_o1, *ptr);
ptr++;
}
} else {
html_output_c(file_tmp_o1, *ptr);
ptr++;
}
if (*ptr == '\\') {
escape = TRUE;
} else {
escape = FALSE;
}
break;
case HTML_RFC2397_FINISH:
if (file_tmp_o1) {
if (file_tmp_o1->fd != -1) {
html_output_flush(file_tmp_o1);
close(file_tmp_o1->fd);
file_tmp_o1->fd = -1;
}
free(file_tmp_o1);
file_tmp_o1 = NULL;
}
state = HTML_SKIP_WS;
escape = FALSE;
quoted = NOT_QUOTED;
next_state = HTML_TAG_ARG;
binary = FALSE;
break;
case HTML_RFC2397_ESC:
if (length == 2) {
html_output_c(file_tmp_o1, value);
} else if (length == 1) {
html_output_c(file_tmp_o1, '%');
html_output_c(file_tmp_o1, value + '0');
} else {
html_output_c(file_tmp_o1, '%');
}
state = HTML_RFC2397_DATA;
break;
case HTML_ESCAPE_CHAR:
if (value < INT64_MAX / 16) {
value *= 16;
} else {
state = next_state;
next_state = HTML_BAD_STATE;
ptr++;
break;
}
length++;
if (isxdigit(*ptr)) {
if (isdigit(*ptr)) {
value += (*ptr - '0');
} else {
value += (tolower(*ptr) - 'a' + 10);
}
} else {
state = next_state;
}
if (length == 2) {
state = next_state;
}
ptr++;
break;
}
}
if (hrefs && hrefs->scanContents && in_ahref && href_contents_begin)
/* end of line, append contents now, resume on next line */
html_tag_contents_append(&contents, href_contents_begin, ptr);
ptrend = NULL;
if (js_state) {
js_process(js_state, js_begin, js_end, line, ptr, in_script, dirname);
js_begin = js_end = NULL;
if (!in_script) {
js_state = NULL;
}
}
if (look_for_screnc && ptr_screnc) {
/* start found, and stuff before it already processed */
ptr = ptr_screnc;
ptr_screnc = NULL;
state = HTML_JSDECODE_LENGTH;
next_state = HTML_BAD_STATE;
continue;
}
free(line);
ptr = line = cli_readchunk(stream_in, m_area, 8192);
if (in_screnc) {
state = HTML_JSDECODE_DECRYPT;
next_state = HTML_BAD_STATE;
} else if (look_for_screnc && !ptr_screnc &&
state != HTML_LOOKFOR_SCRENC) {
saved_next_state = next_state;
next_state = state;
state = HTML_LOOKFOR_SCRENC;
}
if (next_state == state) {
/* safeguard against infloop */
cli_dbgmsg("htmlnorm.c: next_state == state, changing next_state\n");
next_state = HTML_BAD_STATE;
}
}
if (dconf_entconv) {
/* handle "unfinished" entities */
size_t i;
const char *normalized;
entity_val[entity_val_length] = '\0';
normalized = entity_norm(&conv, entity_val);
if (normalized) {
for (i = 0; i < strlen(normalized); i++)
html_output_c(file_buff_o2, normalized[i] & 0xff);
} else {
if (entity_val_length) {
html_output_c(file_buff_o2, '&');
for (i = 0; i < entity_val_length; i++)
html_output_c(file_buff_o2, tolower(entity_val[i]));
}
}
}
retval = TRUE;
abort:
if (line) /* only needed for abort case */
free(line);
if (in_form_action)
free(in_form_action);
if (in_ahref) /* tag not closed, force closing */
html_tag_contents_done(hrefs, in_ahref, &contents);
if (js_state) {
/* output script so far */
cli_js_parse_done(js_state);
cli_js_output(js_state, dirname);
cli_js_destroy(js_state);
js_state = NULL;
}
html_tag_arg_free(&tag_args);
if (!m_area) {
fclose(stream_in);
}
if (file_buff_o2) {
html_output_flush(file_buff_o2);
if (file_buff_o2->fd != -1)
close(file_buff_o2->fd);
free(file_buff_o2);
}
if (file_buff_text) {
html_output_flush(file_buff_text);
if (file_buff_text->fd != -1)
close(file_buff_text->fd);
free(file_buff_text);
file_buff_text = NULL;
}
if (file_tmp_o1) {
if (file_tmp_o1->fd != -1) {
html_output_flush(file_tmp_o1);
close(file_tmp_o1->fd);
}
free(file_tmp_o1);
}
return retval;
}
int html_normalise_mem(unsigned char *in_buff, off_t in_size, const char *dirname, tag_arguments_t *hrefs, const struct cli_dconf *dconf)
{
m_area_t m_area;
m_area.buffer = in_buff;
m_area.length = in_size;
m_area.offset = 0;
m_area.map = NULL;
return cli_html_normalise(-1, &m_area, dirname, hrefs, dconf);
}
int html_normalise_map(fmap_t *map, const char *dirname, tag_arguments_t *hrefs, const struct cli_dconf *dconf)
{
int retval = FALSE;
m_area_t m_area;
m_area.length = map->len;
m_area.offset = 0;
m_area.map = map;
retval = cli_html_normalise(-1, &m_area, dirname, hrefs, dconf);
return retval;
}
int html_screnc_decode(fmap_t *map, const char *dirname)
{
int count, retval = FALSE;
unsigned char *line = NULL, tmpstr[6];
unsigned char *ptr, filename[1024];
int ofd;
struct screnc_state screnc_state;
m_area_t m_area;
memset(&m_area, 0, sizeof(m_area));
m_area.length = map->len;
m_area.offset = 0;
m_area.map = map;
snprintf((char *)filename, 1024, "%s" PATHSEP "screnc.html", dirname);
更新libclamav库1.0.0版本
2023-01-14 18:28:39 +08:00
ofd = open((const char *)filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IWUSR | S_IRUSR);
添加病毒扫描
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if (ofd < 0) {
cli_dbgmsg("open failed: %s\n", filename);
return FALSE;
}
while ((line = cli_readchunk(NULL, &m_area, 8192)) != NULL) {
ptr = (unsigned char *)strstr((char *)line, "#@~^");
if (ptr) {
break;
}
free(line);
line = NULL;
}
if (!line) {
goto abort;
}
/* Calculate the length of the encoded string */
ptr += 4;
count = 0;
do {
if (!*ptr) {
free(line);
ptr = line = cli_readchunk(NULL, &m_area, 8192);
if (!line) {
goto abort;
}
}
if (count < 6)
tmpstr[count] = *ptr;
count++;
ptr++;
} while (count < 8);
memset(&screnc_state, 0, sizeof(screnc_state));
screnc_state.length = base64_chars[tmpstr[0]] < 0 ? 0 : base64_chars[tmpstr[0]] << 2;
screnc_state.length += base64_chars[tmpstr[1]] >> 4;
screnc_state.length += (base64_chars[tmpstr[1]] & 0x0f) << 12;
screnc_state.length += ((base64_chars[tmpstr[2]] >> 2) < 0 ? 0 : (base64_chars[tmpstr[2]] >> 2)) << 8;
screnc_state.length += (base64_chars[tmpstr[2]] & 0x03) << 22;
screnc_state.length += base64_chars[tmpstr[3]] < 0 ? 0 : base64_chars[tmpstr[3]] << 16;
screnc_state.length += (base64_chars[tmpstr[4]] < 0 ? 0 : base64_chars[tmpstr[4]] << 2) << 24;
screnc_state.length += ((base64_chars[tmpstr[5]] >> 4) < 0 ? 0 : (base64_chars[tmpstr[5]] >> 4)) << 24;
cli_writen(ofd, "<script>", strlen("<script>"));
while (screnc_state.length && line) {
screnc_decode(ptr, &screnc_state);
cli_writen(ofd, ptr, strlen((const char *)ptr));
free(line);
line = NULL;
if (screnc_state.length) {
ptr = line = cli_readchunk(NULL, &m_area, 8192);
}
}
cli_writen(ofd, "</script>", strlen("</script>"));
if (screnc_state.length)
cli_dbgmsg("html_screnc_decode: missing %u bytes\n", screnc_state.length);
retval = TRUE;
abort:
close(ofd);
if (line) {
free(line);
}
return retval;
}
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