#include "lib/aes-common.h" #include "lib/md5.h" #include "lib/pbkdf2-sha1.h" #include "lib/pbkdf2-sha256.h" #include <string.h> #include <stdint.h> #include <stdlib.h> #include <stdio.h> #include "encrypt.h" #include "common.h" #include "log.h" //static uint64_t seq=1; static int8_t zero_iv[]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0};//this prog use zero iv,you should make sure first block of data contains a random/nonce data /**** * security of zero_iv + nonce first data block * https://crypto.stackexchange.com/questions/5421/using-cbc-with-a-fixed-iv-and-a-random-first-plaintext-block ****/ char normal_key[16 + 100];//generated from key_string by md5. reserved for compatiblity const int hmac_key_len=64;//generate 512bit long keys, use first n chars when needed const int cipher_key_len=64; unsigned char hmac_key_encrypt[hmac_key_len + 100]; //key for hmac unsigned char hmac_key_decrypt[hmac_key_len + 100]; //key for hmac unsigned char cipher_key_encrypt[cipher_key_len + 100]; //key for aes etc. unsigned char cipher_key_decrypt[cipher_key_len + 100]; //key for aes etc. char gro_xor[256+100];//dirty fix for gro unordered_map<int, const char *> auth_mode_tostring = {{auth_none, "none"}, {auth_md5, "md5"}, {auth_crc32, "crc32"},{auth_simple,"simple"},{auth_hmac_sha1,"hmac_sha1"},}; unordered_map<int, const char *> cipher_mode_tostring={{cipher_none,"none"},{cipher_aes128cfb,"aes128cfb"},{cipher_aes128cbc,"aes128cbc"},{cipher_xor,"xor"},}; //TODO aes-gcm auth_mode_t auth_mode=auth_md5; cipher_mode_t cipher_mode=cipher_aes128cbc; int is_hmac_used=0; int aes128cfb_old=0; //TODO key negotiation and forward secrecy int my_init_keys(const char * user_passwd,int is_client) { char tmp[1000]=""; int len=strlen(user_passwd); strcat(tmp,user_passwd); strcat(tmp,"key1"); md5((uint8_t*)tmp,strlen(tmp),(uint8_t*)normal_key); if(auth_mode==auth_hmac_sha1) is_hmac_used=1; if(is_hmac_used||g_fix_gro||1) { unsigned char salt[400]=""; char salt_text[400]="udp2raw_salt1"; md5((uint8_t*)(salt_text),strlen(salt_text),salt); //TODO different salt per session unsigned char pbkdf2_output1[400]=""; PKCS5_PBKDF2_HMAC_SHA256((uint8_t*)user_passwd,len,salt,16,10000, 32,pbkdf2_output1); //TODO argon2 ? //unsigned char pbkdf2_output2[400]=""; //PKCS5_PBKDF2_HMAC_SHA256(pbkdf2_output1,32,0,0,1, hmac_key_len*2+cipher_key_len*2,pbkdf2_output2); //stretch it const char *info_hmac_encrypt="hmac_key server-->client"; const char *info_hmac_decrypt="hmac_key client-->server"; const char *info_cipher_encrypt="cipher_key server-->client"; const char *info_cipher_decrypt="cipher_key client-->server"; if(is_client) { const char *tmp; tmp=info_hmac_encrypt; info_hmac_encrypt=info_hmac_decrypt;info_hmac_decrypt=tmp; tmp=info_cipher_encrypt; info_cipher_encrypt=info_cipher_decrypt;info_cipher_decrypt=tmp; } else { //nop } assert( hkdf_sha256_expand( pbkdf2_output1,32, (unsigned char *)info_cipher_encrypt,strlen(info_cipher_encrypt), cipher_key_encrypt, cipher_key_len ) ==0); assert( hkdf_sha256_expand( pbkdf2_output1,32, (unsigned char *)info_cipher_decrypt,strlen(info_cipher_decrypt), cipher_key_decrypt, cipher_key_len ) ==0); assert( hkdf_sha256_expand( pbkdf2_output1,32, (unsigned char *)info_hmac_encrypt,strlen(info_hmac_encrypt), hmac_key_encrypt, hmac_key_len ) ==0); assert( hkdf_sha256_expand( pbkdf2_output1,32, (unsigned char *)info_hmac_decrypt,strlen(info_hmac_decrypt), hmac_key_decrypt, hmac_key_len ) ==0); const char *gro_info="gro"; assert( hkdf_sha256_expand( pbkdf2_output1,32, (unsigned char *)gro_info,strlen(gro_info), (unsigned char *)gro_xor, 256 ) ==0); } print_binary_chars(normal_key,16); print_binary_chars((char *)hmac_key_encrypt,hmac_key_len); print_binary_chars((char *)hmac_key_decrypt,hmac_key_len); print_binary_chars((char *)cipher_key_encrypt,cipher_key_len); print_binary_chars((char *)cipher_key_decrypt,cipher_key_len); return 0; } /* * this function comes from http://www.hackersdelight.org/hdcodetxt/crc.c.txt */ unsigned int crc32h(unsigned char *message,int len) { int i, crc; unsigned int byte, c; const unsigned int g0 = 0xEDB88320, g1 = g0>>1, g2 = g0>>2, g3 = g0>>3, g4 = g0>>4, g5 = g0>>5, g6 = (g0>>6)^g0, g7 = ((g0>>6)^g0)>>1; i = 0; crc = 0xFFFFFFFF; while (i!=len) { // Get next byte. byte = message[i]; crc = crc ^ byte; c = ((crc<<31>>31) & g7) ^ ((crc<<30>>31) & g6) ^ ((crc<<29>>31) & g5) ^ ((crc<<28>>31) & g4) ^ ((crc<<27>>31) & g3) ^ ((crc<<26>>31) & g2) ^ ((crc<<25>>31) & g1) ^ ((crc<<24>>31) & g0); crc = ((unsigned)crc >> 8) ^ c; i = i + 1; } return ~crc; } /* void sum(const unsigned char *data,int len,unsigned char* res) { memset(res,0,sizeof(int)); for(int i=0,j=0;i<len;i++,j++) { if(j==4) j=0; res[j]+=data[i]; } return ; }*/ void simple_hash(unsigned char *str,int len,unsigned char res[8]) //djb2+ sdbm { u32_t hash = 5381; u32_t hash2 = 0; int c; int i=0; while(c = *str++,i++!=len) { // hash = ((hash << 5) + hash) + c; /* hash * 33 + c */ hash = ((hash << 5) + hash)^c; /* (hash * 33) ^ c */ hash2 = c + (hash2 << 6) + (hash2 << 16) - hash2; } hash=htonl(hash); hash2=htonl(hash2); memcpy(res,&hash,sizeof(hash)); memcpy(res+sizeof(hash),&hash2,sizeof(hash2)); } int auth_md5_cal(const char *data,char * output,int &len) { memcpy(output,data,len);//TODO inefficient code md5((unsigned char *)output,len,(unsigned char *)(output+len)); len+=16; return 0; } int auth_hmac_sha1_cal(const char *data,char * output,int &len) { mylog(log_trace,"auth_hmac_sha1_cal() is called\n"); memcpy(output,data,len);//TODO inefficient code sha1_hmac(hmac_key_encrypt, 20, (const unsigned char *)data, len,(unsigned char *)(output+len)); //use key len of 20 instead of hmac_key_len, "extra length would not significantly increase the function strength" (rfc2104) len+=20; return 0; } int auth_hmac_sha1_verify(const char *data,int &len) { mylog(log_trace,"auth_hmac_sha1_verify() is called\n"); if(len<20) { mylog(log_trace,"auth_hmac_sha1_verify len<20\n"); return -1; } char res[20]; sha1_hmac(hmac_key_decrypt, 20, (const unsigned char *)data, len-20,(unsigned char *)(res)); if(memcmp(res,data+len-20,20)!=0) { mylog(log_trace,"auth_hmac_sha1 check failed\n"); return -2; } len-=20; return 0; } int auth_crc32_cal(const char *data,char * output,int &len) { memcpy(output,data,len);//TODO inefficient code unsigned int ret=crc32h((unsigned char *)output,len); unsigned int ret_n=htonl(ret); memcpy(output+len,&ret_n,sizeof(unsigned int)); len+=sizeof(unsigned int); return 0; } int auth_simple_cal(const char *data,char * output,int &len) { //char res[4]; memcpy(output,data,len);//TODO inefficient code simple_hash((unsigned char *)output,len,(unsigned char *)(output+len)); len+=8; return 0; } int auth_simple_verify(const char *data,int &len) { if(len<8) return -1; unsigned char res[8]; len-=8; simple_hash((unsigned char *)data,len,res); if(memcmp(res,data+len,8)!=0) return -1; return 0; } int auth_none_cal(const char *data,char * output,int &len) { memcpy(output,data,len); return 0; } int auth_md5_verify(const char *data,int &len) { if(len<16) { mylog(log_trace,"auth_md5_verify len<16\n"); return -1; } char md5_res[16]; md5((unsigned char *)data,len-16,(unsigned char *)md5_res); if(memcmp(md5_res,data+len-16,16)!=0) { mylog(log_trace,"auth_md5_verify md5 check failed\n"); return -2; } len-=16; return 0; } int auth_none_verify(const char *data,int &len) { return 0; } int cipher_xor_encrypt(const char * data, char *output,int &len, char *key) { int i, j; for (i = 0, j = 0; i < len; i++, j++) { if(j==16) j=0; output[i] = data[i]^key[j]; } return 0; } int cipher_xor_decrypt(const char * data, char *output,int &len, char *key) { int i, j; //char tmp[buf_len]; //len=len/16*16+1; //AES128_CBC_decrypt_buffer((uint8_t *)tmp, (uint8_t *)input, len, (uint8_t *)key, (uint8_t *)iv); //for(i=0;i<len;i++) //input[i]=tmp[i]; for (i = 0, j = 0; i < len; i++, j++) { if(j==16) j=0; output[i] = data[i]^key[j]; } return 0; } int padding(char *data ,int &data_len,int padding_num) { int old_len=data_len; data_len+=1; if(data_len%padding_num!=0) { data_len= (data_len/padding_num)*padding_num+padding_num; } unsigned char * p= (unsigned char *)&data[data_len-1]; *p= (data_len-old_len); return 0; } int de_padding(const char *data ,int &data_len,int padding_num) { if(data_len==0) return -1; if((uint8_t)data[data_len-1] >padding_num) return -1; data_len-=(uint8_t)data[data_len-1]; if(data_len<0) { return -1; } return 0; } void aes_ecb_encrypt(const char *data,char *output) { static int first_time=1; char *key=(char*)cipher_key_encrypt; if(aes_key_optimize) { if(first_time==0) key=0; else first_time=0; } AES_ECB_encrypt_buffer((uint8_t*)data,(uint8_t*)key,(uint8_t*)output); } void aes_ecb_encrypt1(char *data) { char buf[16]; memcpy(buf,data,16); aes_ecb_encrypt(buf,data); } void aes_ecb_decrypt(const char *data,char *output) { static int first_time=1; char *key=(char*)cipher_key_decrypt; if(aes_key_optimize) { if(first_time==0) key=0; else first_time=0; } AES_ECB_decrypt_buffer((uint8_t*)data,(uint8_t*)key,(uint8_t*)output); } void aes_ecb_decrypt1(char *data) { char buf[16]; memcpy(buf,data,16); aes_ecb_decrypt(buf,data); } int cipher_aes128cbc_encrypt(const char *data,char *output,int &len,char * key) { static int first_time=1; char buf[buf_len]; memcpy(buf,data,len);//TODO inefficient code if(padding(buf,len,16)<0) return -1; if(aes_key_optimize) { if(first_time==0) key=0; else first_time=0; } AES_CBC_encrypt_buffer((unsigned char *)output,(unsigned char *)buf,len,(unsigned char *)key,(unsigned char *)zero_iv); return 0; } int cipher_aes128cfb_encrypt(const char *data,char *output,int &len,char * key) { static int first_time=1; assert(len>=16); char buf[buf_len]; memcpy(buf,data,len);//TODO inefficient code if(aes_key_optimize) { if(first_time==0) key=0; else first_time=0; } if(!aes128cfb_old) { aes_ecb_encrypt(data,buf); //encrypt the first block } AES_CFB_encrypt_buffer((unsigned char *)output,(unsigned char *)buf,len,(unsigned char *)key,(unsigned char *)zero_iv); return 0; } int auth_crc32_verify(const char *data,int &len) { if(len<int(sizeof(unsigned int))) { mylog(log_debug,"auth_crc32_verify len<%d\n",int(sizeof(unsigned int))); return -1; } unsigned int ret=crc32h((unsigned char *)data,len-sizeof(unsigned int)); unsigned int ret_n=htonl(ret); if(memcmp(data+len-sizeof(unsigned int),&ret_n,sizeof(unsigned int))!=0) { mylog(log_debug,"auth_crc32_verify memcmp fail\n"); return -1; } len-=sizeof(unsigned int); return 0; } int cipher_none_encrypt(const char *data,char *output,int &len,char * key) { memcpy(output,data,len); return 0; } int cipher_aes128cbc_decrypt(const char *data,char *output,int &len,char * key) { static int first_time=1; if(len%16 !=0) {mylog(log_debug,"len%%16!=0\n");return -1;} if(aes_key_optimize) { if(first_time==0) key=0; else first_time=0; } AES_CBC_decrypt_buffer((unsigned char *)output,(unsigned char *)data,len,(unsigned char *)key,(unsigned char *)zero_iv); if(de_padding(output,len,16)<0) return -1; return 0; } int cipher_aes128cfb_decrypt(const char *data,char *output,int &len,char * key) { static int first_time=1; if(len<16) return -1; if(aes_key_optimize) { if(first_time==0) key=0; else first_time=0; } AES_CFB_decrypt_buffer((unsigned char *)output,(unsigned char *)data,len,(unsigned char *)key,(unsigned char *)zero_iv); if(!aes128cfb_old) aes_ecb_decrypt1(output); //decrypt the first block //if(de_padding(output,len,16)<0) return -1; return 0; } int cipher_none_decrypt(const char *data,char *output,int &len,char * key) { memcpy(output,data,len); return 0; } int auth_cal(const char *data,char * output,int &len) { mylog(log_trace,"auth:%d\n",auth_mode); switch(auth_mode) { case auth_crc32:return auth_crc32_cal(data, output, len); case auth_md5:return auth_md5_cal(data, output, len); case auth_simple:return auth_simple_cal(data, output, len); case auth_none:return auth_none_cal(data, output, len); case auth_hmac_sha1:return auth_hmac_sha1_cal(data,output,len); //default: return auth_md5_cal(data,output,len);//default; default: assert(0==1); } return -1; } int auth_verify(const char *data,int &len) { mylog(log_trace,"auth:%d\n",auth_mode); switch(auth_mode) { case auth_crc32:return auth_crc32_verify(data, len); case auth_md5:return auth_md5_verify(data, len); case auth_simple:return auth_simple_verify(data, len); case auth_none:return auth_none_verify(data, len); case auth_hmac_sha1:return auth_hmac_sha1_verify(data,len); //default: return auth_md5_verify(data,len);//default default: assert(0==1); } return -1; } int cipher_encrypt(const char *data,char *output,int &len,char * key) { mylog(log_trace,"cipher:%d\n",cipher_mode); switch(cipher_mode) { case cipher_aes128cbc:return cipher_aes128cbc_encrypt(data,output,len, key); case cipher_aes128cfb:return cipher_aes128cfb_encrypt(data,output,len, key); case cipher_xor:return cipher_xor_encrypt(data,output,len, key); case cipher_none:return cipher_none_encrypt(data,output,len, key); //default:return cipher_aes128cbc_encrypt(data,output,len, key); default: assert(0==1); } return -1; } int cipher_decrypt(const char *data,char *output,int &len,char * key) { mylog(log_trace,"cipher:%d\n",cipher_mode); switch(cipher_mode) { case cipher_aes128cbc:return cipher_aes128cbc_decrypt(data,output,len, key); case cipher_aes128cfb:return cipher_aes128cfb_decrypt(data,output,len, key); case cipher_xor:return cipher_xor_decrypt(data,output,len, key); case cipher_none:return cipher_none_decrypt(data,output,len, key); // default: return cipher_aes128cbc_decrypt(data,output,len,key); default: assert(0==1); } return -1; } int encrypt_AE(const char *data,char *output,int &len /*,char * key*/) { mylog(log_trace,"encrypt_AE is called\n"); char buf[buf_len]; char buf2[buf_len]; memcpy(buf,data,len); if(cipher_encrypt(buf,buf2,len,(char *)cipher_key_encrypt) !=0) {mylog(log_debug,"cipher_encrypt failed ");return -1;} if(auth_cal(buf2,output,len)!=0) {mylog(log_debug,"auth_cal failed ");return -1;} //printf("%d %x %x\n",len,(int)(output[0]),(int)(output[1])); //print_binary_chars(output,len); //use encrypt-then-MAC scheme return 0; } int decrypt_AE(const char *data,char *output,int &len /*,char * key*/) { mylog(log_trace,"decrypt_AE is called\n"); //printf("%d %x %x\n",len,(int)(data[0]),(int)(data[1])); //print_binary_chars(data,len); if(auth_verify(data,len)!=0) {mylog(log_debug,"auth_verify failed\n");return -1;} if(cipher_decrypt(data,output,len,(char *)cipher_key_decrypt) !=0) {mylog(log_debug,"cipher_decrypt failed \n"); return -1;} return 0; } int my_encrypt(const char *data,char *output,int &len /*,char * key*/) { if(len<0) {mylog(log_trace,"len<0");return -1;} if(len>max_data_len) {mylog(log_warn,"len>max_data_len");return -1;} if(is_hmac_used) return encrypt_AE(data,output,len); char buf[buf_len]; char buf2[buf_len]; memcpy(buf,data,len); if(auth_cal(buf,buf2,len)!=0) {mylog(log_debug,"auth_cal failed ");return -1;} if(cipher_encrypt(buf2,output,len,normal_key) !=0) {mylog(log_debug,"cipher_encrypt failed ");return -1;} return 0; } int my_decrypt(const char *data,char *output,int &len /*,char * key*/) { if(len<0) return -1; if(len>max_data_len) {mylog(log_warn,"len>max_data_len");return -1;} if(is_hmac_used) return decrypt_AE(data,output,len); if(cipher_decrypt(data,output,len,normal_key) !=0) {mylog(log_debug,"cipher_decrypt failed \n"); return -1;} if(auth_verify(output,len)!=0) {mylog(log_debug,"auth_verify failed\n");return -1;} return 0; } int encrypt_AEAD(uint8_t *data,uint8_t *output,int &len,uint8_t * key,uint8_t *header,int hlen) { //TODO return -1; } int decrypt_AEAD(uint8_t *data,uint8_t *output,int &len,uint8_t * key,uint8_t *header,int hlen) { //TODO return -1; }