libdispass/dispass.c
Tom Willemse f016198915 Rename sha1.c to dispass.c
This project started out as a test to get SHA1 (actually SHA512)
working, now it's grown up to a DisPass algorithm
implementation (experiment).
2013-11-17 00:42:46 +01:00

138 lines
3.1 KiB
C

#include <stdio.h>
#include <string.h>
#include <openssl/sha.h>
#include <openssl/pem.h>
#include <limits.h>
#define MIN(A, B) ((A) < (B) ? (A) : (B))
#define MAXLEN (SHA512_DIGEST_LENGTH * 2)
char *
base64encode(const void *data, int len)
{ /* Copied from http://stackoverflow.com/a/16511093/459915 */
BIO *b64_bio, *mem_bio;
BUF_MEM *mem_bio_mem_ptr;
char *ret;
b64_bio = BIO_new(BIO_f_base64());
mem_bio = BIO_new(BIO_s_mem());
BIO_push(b64_bio, mem_bio);
BIO_set_flags(b64_bio, BIO_FLAGS_BASE64_NO_NL);
BIO_write(b64_bio, data, len);
BIO_flush(b64_bio);
BIO_get_mem_ptr(mem_bio, &mem_bio_mem_ptr);
BIO_set_close(mem_bio, BIO_NOCLOSE);
BIO_free_all(b64_bio);
(*mem_bio_mem_ptr).data[(*mem_bio_mem_ptr).length] = '\0';
ret = calloc((*mem_bio_mem_ptr).length, sizeof(char));
strncpy(ret, (*mem_bio_mem_ptr).data, (*mem_bio_mem_ptr).length);
BUF_MEM_free(mem_bio_mem_ptr);
return ret;
}
void
sha512_to_string(unsigned char *data, char *buff)
{
int i;
for (i = 0; i < SHA512_DIGEST_LENGTH; i++) {
char sbuff[3] = { '\0' };
sprintf(sbuff, "%02x", data[i]);
strcat(buff, sbuff);
}
}
void
rmchar(char rm, char **s)
{
int i, j = 0;
char *new;
size_t len;
if (!strchr(*s, rm))
return;
len = strlen(*s);
new = calloc(len + 1, sizeof(char));
for (i = 0; i < len; i++) {
char c;
if ((c = (*s)[i]) != rm)
new[j++] = c;
}
strncpy(*s, new, len);
free(new);
}
char *
dispass1(char *label, char *password, int len, long long unsigned seqno)
{
unsigned char *d;
size_t tbufflen = strlen(label) + strlen(password) + 1;
char *tbuff = calloc(tbufflen, sizeof(char));
char buff[MAXLEN + 1] = { '\0' };
char *b64;
strcat(tbuff, label);
strcat(tbuff, password);
d = SHA512((unsigned char *)tbuff, strlen(tbuff), 0);
free(tbuff);
sha512_to_string(d, buff);
b64 = base64encode(buff, strlen(buff));
b64[MIN(len, MAXLEN)] = '\0';
rmchar('=', &b64);
return b64;
}
char *
dispass2(char *label, char *password, int len, long long unsigned seqno)
{
unsigned char *d;
char ibuff[300];
char *tbuff, *b64;
char buff[MAXLEN + 1] = { '\0' };
sprintf(ibuff, "%llu", seqno);
tbuff = calloc(strlen(label) + strlen(ibuff) + strlen(password) + 1,
sizeof(char));
strcat(tbuff, label);
strcat(tbuff, ibuff);
strcat(tbuff, password);
d = SHA512((unsigned char *)tbuff, strlen(tbuff), 0);
free(tbuff);
sha512_to_string(d, buff);
b64 = base64encode(buff, strlen(buff));
b64[MIN(len, MAXLEN)] = '\0';
rmchar('=', &b64);
return b64;
}
int main(int argc, char *argv[])
{
char *test1, *test2, *test3, *test4;
test1 = dispass1("test", "qqqqqqqq", 30, 0);
test2 = dispass1("test2", "qqqqqqqq", 50, 0);
test3 = dispass2("test", "qqqqqqqq", 30, 1);
test4 = dispass2("test2", "qqqqqqqq", 50, 10);
printf("%s\n", test1);
printf("%s\n", test2);
printf("%s\n", test3);
printf("%s\n", test4);
free(test1);
free(test2);
free(test3);
free(test4);
return 0;
}