int des_read_pw_string(char *buf, int length, const char *prompt,
int verify)
{
char buff[BUFSIZ];
int ret;
ret=des_read_pw(buf,buff,(length>BUFSIZ)?BUFSIZ:length,prompt,verify);
OPENSSL_cleanse(buff,BUFSIZ);
return(ret);
}
int enc(char *sopath,char *filename)
{
//printf("you are in the enc program\n");
SHA_CTX md;
int eight=8;
DES_key_schedule schedule1;
DES_key_schedule schedule2;
DES_key_schedule schedule3;
FILE *fp;
unsigned char buffer[10],DES_output[8];
char DES_input[8],ch;
unsigned char digest[20],file_digest[20];
int count,i,len_of_pass,verify=1,no_of_bytes;
unsigned char random_bits1[20],random_bits2[20],DES_key1[8],DES_key2[8],DES_key3[8],IV[8];
char *buf,*buff;
if(RAND_bytes(random_bits1,20)==0)
{
fprintf(stderr,"Error obtaining 20 bytes of random bits from OPENSSL\n");
exit(1);
}
if(RAND_bytes(random_bits2,20)==0)
{
fprintf(stderr,"Error obtaining 20 bytes of random bits from OPENSSL\n");
exit(1);
}
/**************************************
COMPUTE SHA1 OF FILE
**************************************/
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"(input file %s does not exist)\n",filename);
exit(1);
}
SHA1_Init(&md);
while((count=fread(&buffer,1,10,fp)))
{
SHA1_Update(&md,buffer,count);
}
SHA1_Final(file_digest,&md);
/* for(i=0;i<20;i++)
{
printf("%02x",file_digest[i]);
}*/
/**************************************
ASK FOR PASSWORD FOR DES
**************************************/
buf=(char *)malloc(4096*sizeof(char));
buff=(char *)malloc(4096*sizeof(char));
des_read_pw(buf,buff,4096,"Enter passphrase for DES encryption: ",verify);
//printf("buff=%s",buf);
//printf("buff2=%s\n",buff);
len_of_pass=strlen(buf);
//printf("len_of_pass=%d\n",len_of_pass);
/**************************************
GENERATE SHA1 OF THE PASSWORD
**************************************/
SHA1_Init(&md);
//free(&md);
//SHA1_Update(&md,"yesnomaybe",10);
SHA1_Update(&md,buf,strlen(buf));
SHA1_Final(digest,&md);
//printf("The SHA1 of password is\n");
for(i=0;i<20;i++)
{
//printf("%02x",digest[i]);
}
//printf("\n");
/*******************************************
COMPUTE SHA1 OF X AND RANDOM BITS(RB1) 1
*******************************************/
/* SHA1_Init(&md);
SHA1_Update(&md,digest,20);
SHA1_Update(&md,HW4_random_bits_1,20);
SHA1_Final(X_RB1,&md);
for(i=0;i<20;i++)
{
//printf("%02x",X_RB1[i]);
}
//printf("\n");*/
/******************************************
COMPUTE SHA1 OF RB1(Y) AND RANDOM BITS 2(RB2)
******************************************/
/* SHA1_Init(&md);
SHA1_Update(&md,X_RB1,20);
SHA1_Update(&md,HW4_random_bits_2,20);
SHA1_Final(X_RB2,&md);
for(i=0;i<20;i++)
{
//printf("%02x",X_RB2[i]);
}
//printf("\n");*/
/***************************************
COMPUTER IV AND 3 DES KEYS
***************************************/
// SC_3des_key_gen(NULL,digest,IV,DES_key1,DES_key2,DES_key3);
SmartcardState pss=(SmartcardState)NULL;
void *handle=NULL;
//void *vp =NULL;
SC_Init_Func *pfn_init=NULL;
SC_Cleanup_Func *pfn_cleanup=NULL;
SC_GetSignatureSize_Func *pfn_getsigsize=NULL;
SC_3DesKeyGen_Func *pfn_sc_enc=NULL;
handle = dlopen(sopath, RTLD_NOW|RTLD_GLOBAL);
if (handle==NULL)
{
//fprintf(stderr, "%s\n",sopath);
fprintf(stderr, "%s\n",
dlerror());
fprintf(stderr,"dlopen() failed\n");
exit(1);
}
pfn_init = (SC_Init_Func*)dlsym(handle,"SC_init");
pfn_cleanup = (SC_Cleanup_Func*)dlsym(handle,"SC_cleanup");
pfn_getsigsize = (SC_GetSignatureSize_Func*)dlsym(handle,"SC_get_signature_size");
pfn_sc_enc = (SC_3DesKeyGen_Func *)dlsym(handle,"SC_3des_key_gen");
if(pfn_init==NULL || pfn_cleanup==NULL || pfn_getsigsize==NULL || pfn_sc_enc==NULL)
{
fprintf(stderr,"(cannot find smartcard functions in this library)\n");
exit(1);
}
pss = (pfn_init)();
//printf("sig size is %d\n", (pfn_getsigsize)(pss));
(pfn_sc_enc) (pss,digest,IV,DES_key1,DES_key2,DES_key3);
(pfn_cleanup)(pss);
dlclose(handle);
/* for(i=0;i<8;i++)
IV[i]=X_RB1[i];
for(i=8,j=0;i<16;i++,j++)
DES_key1[j]=X_RB1[i];
for(i=0;i<8;i++)
DES_key2[i]=X_RB2[i];
for(i=8,j=0;i<16;i++,j++)
DES_key3[j]=X_RB2[i];
printf("IV=");
for(i=0;i<8;i++)
printf("%02x",IV[i]);
printf("\nDES KEY 1=");
for(i=0;i<8;i++)
printf("%02x",DES_key1[i]);
printf("\nDES key 2=");
for(i=0;i<8;i++)
printf("%02x",DES_key2[i]);
printf("\nDES key 3=");
for(i=0;i<8;i++)
printf("%02x",DES_key3[i]);
printf("\n");*/
DES_set_odd_parity((DES_cblock *)DES_key1);
DES_set_odd_parity((DES_cblock *)DES_key2);
DES_set_odd_parity((DES_cblock *)DES_key3);
DES_key_sched((DES_cblock *)DES_key1,&schedule1);
DES_set_key((DES_cblock *)DES_key1,&schedule1);
DES_key_sched((DES_cblock *)DES_key2,&schedule2);
DES_set_key((DES_cblock *)DES_key2,&schedule2);
DES_key_sched((DES_cblock *)DES_key3,&schedule3);
DES_set_key((DES_cblock *)DES_key3,&schedule3);
/******************************************
READ FILE 8 BYTES AT A TIME AND ENCRYPT IT
******************************************/
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"{input file %s does not exist}\n",filename);
exit(1);
}
i=0;
while((count=fread(&ch,1,1,fp)))
{
i++;
}
// printf("no. of bytes=%d\n",i);
no_of_bytes=i%8;
fclose(fp);
printf("HW4");
if(no_of_bytes>0)
printf("%c",no_of_bytes);
else
printf("%c",eight);
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"{input file %s does not exist}\n",filename);
exit(1);
}
while((count=fread(&DES_input,1,8,fp)))
{
if(count!=8)
{
for(i=count;i<8;i++)
DES_input[i]='\0';
DES_ede3_cbc_encrypt(DES_input,DES_output,8,&schedule1,&schedule2,&schedule3,(DES_cblock*)IV,1);
for(i=0;i<8;i++)
printf("%c",DES_output[i]);
// printf("%s",DES_output);
}
else
{
// printf("%d\n",count);
DES_ede3_cbc_encrypt(DES_input,DES_output,8,&schedule1,&schedule2,&schedule3,(DES_cblock*)IV,1);
for(i=0;i<8;i++)
printf("%c",DES_output[i]);
// printf("%s",DES_output);
}
}
for(i=0;i<20;i++)
printf("%c",file_digest[i]);
return 1;
}
int dec(char *sopath,char *filename)
{
//printf("you are in the enc program\n");
SHA_CTX md;
DES_key_schedule schedule1;
DES_key_schedule schedule2;
DES_key_schedule schedule3;
FILE *fp;
char DES_output[9],DES_input[9];
unsigned char buffer[10];
char ch;
unsigned char digest[20],file_digest[20];
int count,i,len_of_pass,verify=0,n,last_byte_size,to_read_upto,count_buf_size,temp_count;
unsigned char random_bits1[20],random_bits2[20],DES_key1[8],DES_key2[8],DES_key3[8],IV[8];
char *buf,*buff;
if(RAND_bytes(random_bits1,20)==0)
{
fprintf(stderr,"Error obtaining 20 bytes of random bits from OPENSSL\n");
exit(1);
}
if(RAND_bytes(random_bits2,20)==0)
{
fprintf(stderr,"Error obtaining 20 bytes of random bits from OPENSSL\n");
exit(1);
}
/**************************************
COMPUTE SHA1 OF FILE
**************************************/
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"(%s file does not exist)\n",filename);
exit(1);
}
count=0;
while(fread(&ch,1,1,fp))
{
if(count==0)
{
if(ch!='H')
{
fprintf(stderr,"(%s is not generated by the enc command)\n",filename);
exit(1);
}
}
if(count==1)
{
if(ch!='W')
{
fprintf(stderr,"(%s is not generated by the enc command)\n",filename);
}
}
if(count==2)
{
if(ch!='4')
{
fprintf(stderr,"(%s is not generated by the enc command)\n",filename);
}
}
count++;
}
fclose(fp);
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"(%s is not generated by enc command)\n",filename);
exit(1);
}
SHA1_Init(&md);
while((count=fread(&buffer,1,10,fp)))
{
SHA1_Update(&md,buffer,count);
}
SHA1_Final(file_digest,&md);
/* for(i=0;i<20;i++)
{
printf("%02x",file_digest[i]);
}*/
/**************************************
ASK FOR PASSWORD FOR DES
**************************************/
buf=(char *)malloc(4096*sizeof(char));
buff=(char *)malloc(4096*sizeof(char));
des_read_pw(buf,buff,4096,"Enter passphrase for DES decryption: ",verify);
//printf("buff=%s",buf);
//printf("buff2=%s\n",buff);
len_of_pass=strlen(buf);
//printf("len_of_pass=%d\n",len_of_pass);
/**************************************
GENERATE SHA1 OF THE PASSWORD
**************************************/
SHA1_Init(&md);
//free(&md);
//SHA1_Update(&md,"yesnomaybe",10);
SHA1_Update(&md,buf,strlen(buf));
SHA1_Final(digest,&md);
//printf("The SHA1 of password is\n");
for(i=0;i<20;i++)
{
//printf("%02x",digest[i]);
}
//printf("\n");
/*******************************************
COMPUTE SHA1 OF X AND RANDOM BITS(RB1) 1
*******************************************/
/* SHA1_Init(&md);
SHA1_Update(&md,digest,20);
SHA1_Update(&md,HW4_random_bits_1,20);
SHA1_Final(X_RB1,&md);
for(i=0;i<20;i++)
{
//printf("%02x",X_RB1[i]);
}
//printf("\n");*/
/******************************************
COMPUTE SHA1 OF RB1(Y) AND RANDOM BITS 2(RB2)
******************************************/
/* SHA1_Init(&md);
SHA1_Update(&md,X_RB1,20);
SHA1_Update(&md,HW4_random_bits_2,20);
SHA1_Final(X_RB2,&md);
for(i=0;i<20;i++)
{
//printf("%02x",X_RB2[i]);
}
//printf("\n");*/
/***************************************
COMPUTER IV AND 3 DES KEYS
***************************************/
// SC_3des_key_gen(NULL,digest,IV,DES_key1,DES_key2,DES_key3);
SmartcardState pss=(SmartcardState)NULL;
void *handle=NULL;
//void *vp =NULL;
SC_Init_Func *pfn_init=NULL;
SC_Cleanup_Func *pfn_cleanup=NULL;
SC_GetSignatureSize_Func *pfn_getsigsize=NULL;
SC_3DesKeyGen_Func *pfn_sc_dec=NULL;
handle = dlopen(sopath, RTLD_NOW|RTLD_GLOBAL);
if (handle==NULL)
{
//fprintf(stderr, "%s\n",sopath);
fprintf(stderr, "%s\n",
dlerror());
fprintf(stderr,"dlopen() failed\n");
exit(1);
}
pfn_init = (SC_Init_Func*)dlsym(handle,"SC_init");
pfn_cleanup = (SC_Cleanup_Func*)dlsym(handle,"SC_cleanup");
pfn_getsigsize = (SC_GetSignatureSize_Func*)dlsym(handle,"SC_get_signature_size");
pfn_sc_dec = (SC_3DesKeyGen_Func *)dlsym(handle,"SC_3des_key_gen");
if(pfn_init==NULL || pfn_cleanup==NULL || pfn_getsigsize==NULL || pfn_sc_dec==NULL)
{
fprintf(stderr,"(cannot find smartcard functions in this library)\n");
exit(1);
}
pss = (pfn_init)();
//printf("sig size is %d\n", (pfn_getsigsize)(pss));
//int sz=(pfn_getsigsize)(pss);
(pfn_sc_dec) (pss,digest,IV,DES_key1,DES_key2,DES_key3);
(pfn_cleanup)(pss);
dlclose(handle);
/* for(i=0;i<8;i++)
IV[i]=X_RB1[i];
for(i=8,j=0;i<16;i++,j++)
DES_key1[j]=X_RB1[i];
for(i=0;i<8;i++)
DES_key2[i]=X_RB2[i];
for(i=8,j=0;i<16;i++,j++)
DES_key3[j]=X_RB2[i];
printf("IV=");
for(i=0;i<8;i++)
printf("%02x",IV[i]);
printf("\nDES KEY 1=");
for(i=0;i<8;i++)
printf("%02x",DES_key1[i]);
printf("\nDES key 2=");
for(i=0;i<8;i++)
printf("%02x",DES_key2[i]);
printf("\nDES key 3=");
for(i=0;i<8;i++)
printf("%02x",DES_key3[i]);
printf("\n");*/
DES_set_odd_parity((DES_cblock *)DES_key1);
DES_set_odd_parity((DES_cblock *)DES_key2);
DES_set_odd_parity((DES_cblock *)DES_key3);
DES_key_sched((DES_cblock *)DES_key1,&schedule1);
DES_set_key((DES_cblock *)DES_key1,&schedule1);
DES_key_sched((DES_cblock *)DES_key2,&schedule2);
DES_set_key((DES_cblock *)DES_key2,&schedule2);
DES_key_sched((DES_cblock *)DES_key3,&schedule3);
DES_set_key((DES_cblock *)DES_key3,&schedule3);
/******************************************
READ FILE 8 BYTES AT A TIME AND ENCRYPT IT
******************************************/
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"{input file %s does not exist}\n",filename);
exit(1);
}
i=0;
while((count=fread(&ch,1,1,fp)))
{
i++;
if(i==4)
{
last_byte_size=(int)ch;
}
}//while ends
fclose(fp);
// printf("last_bytes_size=%d",last_byte_size);
// printf("\ntotal count=%d\n",i);
to_read_upto=i-20;
// printf("to read upto=%d\n",to_read_upto);
if((fp=fopen(filename,"rb"))==NULL)
{
fprintf(stderr,"{input file %s does not exist}\n",filename);
exit(1);
}
n=0;count_buf_size=0;i=0;temp_count=0;
for(i=0;i<4;i++)
fread(&ch,1,1,fp);
n=4;
while(!feof(fp))
{
if(n==(to_read_upto-8))
{
// printf("\nlast byte reading\n");
for(i=0;i<8;i++)
DES_input[i]=fgetc(fp);
DES_ede3_cbc_encrypt(DES_input,DES_output,8,&schedule1,&schedule2,&schedule3,(DES_cblock*)IV,DES_DECRYPT);
for(i=0;i<last_byte_size;i++)
printf("%c",DES_output[i]);
exit(1);
}
for(i=0;i<8;i++)
{
if(n==(to_read_upto+1))
exit(1);
n++;
DES_input[i]=fgetc(fp);
}
DES_ede3_cbc_encrypt(DES_input,DES_output,8,&schedule1,&schedule2,&schedule3,(DES_cblock*)IV,DES_DECRYPT);
for(i=0;i<8;i++)
printf("%c",DES_output[i]);
}//while feof ends
/* while((count=fread(&ch,1,1,fp)))
{
// printf("%c",ch);
n++;
if(n>4)//skip first four bytes of encrypted file
{
if(n==to_read_upto+1)
break;
DES_input[count_buf_size]=ch;
printf("%c",DES_input[count_buf_size]);
count_buf_size++;
if(count_buf_size==7)
{
//for(i=0;i<8;i++)
//printf("%c",DES_input[i]);
temp_count++;
DES_ede3_cbc_encrypt(DES_input,DES_output,8,&schedule1,&schedule2,&schedule3,(DES_cblock*)IV,DES_DECRYPT);
if(n==to_read_upto-7)
{
// printf("in other loop\n");
// for(i=0;i<last_byte_size;i++)
// printf("%c",DES_output[i]);
}
else
{
// for(i=0;i<8;i++)
// printf("%c",DES_output[i]);
count_buf_size=0;
}
}
}//if count >4 ends
}
// printf("count=%d\n",temp_count);
// printf("loop count=%d\n",n);
for(i=0;i<20;i++)
printf("%c",file_digest[i]);
//printf("%s\n",file_digest);*/
return 1;
}
