mirror of
https://github.com/bol-van/zapret.git
synced 2024-11-11 17:29:16 +05:00
133 lines
3.0 KiB
C
133 lines
3.0 KiB
C
#define _GNU_SOURCE
|
|
|
|
#include "protocol.h"
|
|
#include "helpers.h"
|
|
#include <string.h>
|
|
#include <ctype.h>
|
|
#include <arpa/inet.h>
|
|
#include <string.h>
|
|
|
|
const char *http_methods[] = { "GET /","POST /","HEAD /","OPTIONS /","PUT /","DELETE /","CONNECT /","TRACE /",NULL };
|
|
bool IsHttp(const uint8_t *data, size_t len)
|
|
{
|
|
const char **method;
|
|
size_t method_len;
|
|
for (method = http_methods; *method; method++)
|
|
{
|
|
method_len = strlen(*method);
|
|
if (method_len <= len && !memcmp(data, *method, method_len))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
bool HttpExtractHost(const uint8_t *data, size_t len, char *host, size_t len_host)
|
|
{
|
|
const uint8_t *p, *s, *e=data+len;
|
|
|
|
p = (uint8_t*)strncasestr((char*)data, "\nHost:", len);
|
|
if (!p) return false;
|
|
p+=6;
|
|
while(p<e && (*p==' ' || *p=='\t')) p++;
|
|
s=p;
|
|
while(s<e && (*s!='\r' && *s!='\n' && *s!=' ' && *s!='\t')) s++;
|
|
if (s>p)
|
|
{
|
|
size_t slen = s-p;
|
|
if (host && len_host)
|
|
{
|
|
if (slen>=len_host) slen=len_host-1;
|
|
for(size_t i=0;i<slen;i++) host[i]=tolower(p[i]);
|
|
host[slen]=0;
|
|
}
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
bool IsTLSClientHello(const uint8_t *data, size_t len)
|
|
{
|
|
return len>=6 && data[0]==0x16 && data[1]==0x03 && data[2]==0x01 && data[5]==0x01 && (ntohs(*(uint16_t*)(data+3))+5)<=len;
|
|
}
|
|
bool TLSFindExt(const uint8_t *data, size_t len, uint16_t type, const uint8_t **ext, size_t *len_ext)
|
|
{
|
|
// +0
|
|
// u8 ContentType: Handshake
|
|
// u16 Version: TLS1.0
|
|
// u16 Length
|
|
// +5
|
|
// u8 HandshakeType: ClientHello
|
|
// u24 Length
|
|
// u16 Version
|
|
// c[32] random
|
|
// u8 SessionIDLength
|
|
// <SessionID>
|
|
// u16 CipherSuitesLength
|
|
// <CipherSuites>
|
|
// u8 CompressionMethodsLength
|
|
// <CompressionMethods>
|
|
// u16 ExtensionsLength
|
|
|
|
size_t l,ll;
|
|
|
|
l = 1+2+2+1+3+2+32;
|
|
// SessionIDLength
|
|
if (len<(l+1)) return false;
|
|
ll = data[6]<<16 | data[7]<<8 | data[8]; // HandshakeProtocol length
|
|
if (len<(ll+9)) return false;
|
|
l += data[l]+1;
|
|
// CipherSuitesLength
|
|
if (len<(l+2)) return false;
|
|
l += ntohs(*(uint16_t*)(data+l))+2;
|
|
// CompressionMethodsLength
|
|
if (len<(l+1)) return false;
|
|
l += data[l]+1;
|
|
// ExtensionsLength
|
|
if (len<(l+2)) return false;
|
|
|
|
data+=l; len-=l;
|
|
l=ntohs(*(uint16_t*)data);
|
|
data+=2; len-=2;
|
|
if (l<len) return false;
|
|
|
|
uint16_t ntype=htons(type);
|
|
while(l>=4)
|
|
{
|
|
uint16_t etype=*(uint16_t*)data;
|
|
size_t elen=ntohs(*(uint16_t*)(data+2));
|
|
data+=4; l-=4;
|
|
if (l<elen) break;
|
|
if (etype==ntype)
|
|
{
|
|
if (ext && len_ext)
|
|
{
|
|
*ext = data;
|
|
*len_ext = elen;
|
|
}
|
|
return true;
|
|
}
|
|
data+=elen; l-=elen;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
bool TLSHelloExtractHost(const uint8_t *data, size_t len, char *host, size_t len_host)
|
|
{
|
|
const uint8_t *ext;
|
|
size_t elen;
|
|
|
|
if (!TLSFindExt(data,len,0,&ext,&elen)) return false;
|
|
// u16 data+0 - name list length
|
|
// u8 data+2 - server name type. 0=host_name
|
|
// u16 data+3 - server name length
|
|
if (elen<5 || ext[2]!=0) return false;
|
|
size_t slen = ntohs(*(uint16_t*)(ext+3));
|
|
ext+=5; elen-=5;
|
|
if (slen<elen) return false;
|
|
if (ext && len_host)
|
|
{
|
|
if (slen>=len_host) slen=len_host-1;
|
|
for(size_t i=0;i<slen;i++) host[i]=tolower(ext[i]);
|
|
host[slen]=0;
|
|
}
|
|
return true;
|
|
}
|