cryptopals_c

commit 412d14330fd9fbd3e649e9c5f370f47a5ae65630
parent d6af37147d971612c349a27bc26f7fb8ba44b34d
Author: superpozycja <anna@superpozycja.net>
Date:   Sun,  1 Sep 2024 19:43:42 +0200

rename the lib; in c6 move functions out

Diffstat:
M
src/s1/c3.c
 | 
2
+-
M
src/s1/c4.c
 | 
2
+-
M
src/s1/c5.c
 | 
2
+-
M
src/s1/c6.c
 | 
68
++++----------------------------------------------------------------

4 files changed, 7 insertions(+), 67 deletions(-)
diff --git a/src/s1/c3.c b/src/s1/c3.c
@@ -1,5 +1,5 @@
 #include <ba.h>
-#include <cryptanalysis.h>
+#include <analysis.h>
 
 int main(int argc, char* argv[]) 
 {
diff --git a/src/s1/c4.c b/src/s1/c4.c
@@ -1,7 +1,7 @@
 #include <stdio.h>
 #include <ctype.h>
 #include <ba.h>
-#include <cryptanalysis.h>
+#include <analysis.h>
 
 #define MAXLEN 1000
 
diff --git a/src/s1/c5.c b/src/s1/c5.c
@@ -1,7 +1,7 @@
 #include <stdio.h>
 #include <ctype.h>
 #include <ba.h>
-#include <cryptanalysis.h>
+#include <analysis.h>
 
 int main()
 {
diff --git a/src/s1/c6.c b/src/s1/c6.c
@@ -1,70 +1,10 @@
 #include <stdio.h>
 #include <ctype.h>
 #include <ba.h>
-#include <cryptanalysis.h>
+#include <analysis.h>
 #include <util.h>
 
-float i_c(ba *ct)
-{
-	unsigned int occur[256];
-	unsigned int i;
-	unsigned int t;
-	float res;
-
-	res = 0;
-	memset(occur, 0, sizeof(occur));
-
-	for (i = 0; i < ct->len; i++)
-		occur[ct->val[i]]++;
-
-	t = 0;
-	for (i = 0; i < 256; i++)
-		t += occur[i] * (occur[i] - 1);
-
-	res = t / (float) (ct->len * (ct->len - 1));
-	return res;
-}
-
-float get_i_c_m(ba *ct, unsigned int m)
-{
-	float res;
-	int i;
-	res = 0;
-	for (i = 0; i < m; i++) {
-		ba *chunk = (ba *) malloc(sizeof(ba));
-		int j;
-		int k;
-
-		chunk->len = ct->len / m;
-		chunk->val = (uint8_t *) malloc(sizeof(uint8_t) * chunk->len);
-		
-		for (j = 0, k = 0; j < chunk->len &&  k + i < ct->len; j++, k += m)
-			chunk->val[j] = ct->val[k + i];
-		res += i_c(chunk);
-	}
-	return res / m;
-}
-
-unsigned int guess_m(ba *ct)
-{
-	unsigned int best;
-	float max;
-	int m;
-
-	max = 0;
-	for (m = 1; m < 40; m++) {
-		float avg;
-		
-		avg = get_i_c_m(ct, m);
-		if (avg > max) {
-			max = avg;
-			best = m;
-		}
-	}
-	return best;
-}
-
-void break_m(ba *ct, unsigned int m)
+void break_w_keylen(ba *ct, unsigned int m)
 {
 	int i;
 
@@ -113,9 +53,9 @@ int main(int argc, char *argv[])
 	base64_to_hex(&hex, b64);
 	ct = ba_from_hex(hex);	
 	
-	int m = guess_m(ct);
+	int m = guess_vigenere_keylen(ct);
 
-	break_m(ct, m);
+	break_w_keylen(ct, m);
 
 	ba_fprint_ascii(ct, stdout, 0);
 	printf("\n");