docs only on master

.gitea/workflows/jobs.yaml

@@ -1,9 +1,6 @@
 ---
 name: Test and Deploy
-on:
+on: [push]
-  push:
-    branches:
-      - master
 
 jobs:
   test:
@@ -29,6 +26,7 @@ jobs:
 
   docs:
     runs-on: ubuntu-latest
+    if: gitea.ref == 'refs/heads/master'
     timeout-minutes: 5
     steps:
       - name: Checkout repository

.idea/misc.xml

@@ -1,4 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="CMakePythonSetting">
+    <option name="pythonIntegrationState" value="YES" />
+  </component>
   <component name="CMakeWorkspace" PROJECT_DIR="$PROJECT_DIR$" />
 </project>

docs/crypto.md

@@ -2,6 +2,9 @@
 
 Cryptographic tools
 
+Any functions that return string representations of bytes in hexadecimal format will
+always be formatted with no leading `0x` and lower case letters
+
 ## Functions
 
 ### b64_encode
@@ -26,22 +29,25 @@ unsigned char *b64_decode(const char *s, size_t sz, size_t *decode_sz);
 ### hex_encode
 
 Encodes an array of bytes into a string in hex representation. For example, converts 
-`[0xDE, 0xAD, 0xBE, 0xEF]` into `"DEADBEEF"`. The returned string will always be in capital
+`[0xDE, 0xAD, 0xBE, 0xEF]` into `"deadbeef"`. User is responsible for freeing the returned string
-letters with no leading `0x`. User is responsible for the freeing of the returned string
 
 ```c
 const char *hex_encode(const unsigned char *hex, size_t sz);
 
 // Example
+unsigned char h[4] = {
+    0xde, 0xad, 0xbe, 0xef
+};
 const char *s = hex_encode(h, 4);
-assert(strcmp(s, "DEADBEEF") == 0);
+assert(strcmp(s, "deadbeef") == 0);
 free(s);
 ```
 
 ### hex_decode
 
 Decodes a string of characters representing hexadecimal bytes into an array of `unsigned char`.
-For example, converts `"DEADBEEF"` into `[0xDE, 0xAD, 0xBE, 0xEF]`. User is reponsible for the
+Characters can be in upper or lower case, and can start with a leading `0x` or not.
+For example, converts `"DEADBEEF"` into `[0xde, 0xad, 0xbe, 0xef]`. User is reponsible for the
 freeing of the returned byte array
 
 ```c
@@ -83,3 +89,19 @@ responsible for freeing the returned array
 ```c
 const unsigned char *repeating_key_xor_s(const char* s, const char* key);
 ```
+
+### hamming_distance
+
+Calculates the Hamming Distance (the number of differing bits) between two arrays of unsigned bytes
+
+```c
+unsigned int hamming_distance(unsigned char *a, unsigned char *b);
+```
+
+### hamming_distance_s
+
+Calculates the Hamming Distance (the number of differing bits) between two strings
+
+```c
+unsigned int hamming_distance_s(const char *a, const char *b);
+```

include/lfcrypto.h

@@ -13,4 +13,7 @@ const char *hex_to_str(const unsigned char *hex, size_t sz);
 const unsigned char* repeating_key_xor(const unsigned char* s, size_t s_sz, const unsigned char* key, size_t k_sz);
 const unsigned char *repeating_key_xor_s(const char* s, const char* key);
 
+unsigned int hamming_distance_s(const char *a, const char *b);
+unsigned int hamming_distance(unsigned char *a, unsigned char *b, size_t sz);
+
 #endif // LIBFLINT_CRYPTO_H

include/lfmacos.h

@@ -3,6 +3,8 @@
 
 #if defined(__APPLE__) || defined(__MACH__)
 
+#include <time.h>
+
 typedef struct {
     double total_user_time;
     double total_kernel_time;
@@ -18,6 +20,7 @@ typedef struct {
 
 ProcessData *new_ProcessData();
 int update_process(pid_t pid, ProcessData *proc);
+void *reallocarray(void *optr, size_t nmemb, size_t size);
 
 #endif /* defined(__APPLE__) || defined(__MACH__) */
 #endif /* LIBFLINT_MACOS_H */

src/crypto.c

@@ -204,16 +204,22 @@ unsigned char *b64_decode(const char *s, size_t sz, size_t *decode_sz) {
 
 unsigned char *hex_decode(const char *orig, size_t *sz) {
     size_t buf_sz = strlen(orig) + 1;
+    char *sptr = orig;
+    if (strncmp(orig, "0x", 2) == 0) {
+        buf_sz -= 2;
+        sptr += 2;
+    }
+
     if (strlen(orig) % 2 != 0) {
         buf_sz += 1;
     }
 
     char *buf = malloc(sizeof(char) * buf_sz);
-    if (strlen(orig) % 2 != 0) {
+    if (strlen(sptr) % 2 != 0) {
-        strcpy(buf + 1, orig);
+        strcpy(buf+ 1, sptr);
         buf[0] = '0';
     } else {
-        strcpy(buf, orig);
+        strcpy(buf, sptr);
     }
     buf[buf_sz - 1] = '\0';
 
@@ -265,3 +271,29 @@ const unsigned char* repeating_key_xor(const unsigned char* s, size_t s_sz, cons
 const unsigned char *repeating_key_xor_s(const char* s, const char* key) {
     return repeating_key_xor((unsigned char*)s, strlen(s), (unsigned char*)key, strlen(key));
 }
+
+unsigned int hamming_distance_s(const char *a, const char *b) {
+    size_t sz = strlen(a);
+    if (sz != strlen(b)) {
+        return -1;
+    }
+
+    return hamming_distance((unsigned char *)a, (unsigned char *)b, sz);
+}
+
+unsigned int hamming_distance(unsigned char *a, unsigned char *b, size_t sz) {
+    unsigned int hamming = 0;
+    for (size_t i = 0; i < sz; ++i) {
+        if (a[i] == b[i]) {
+            continue;
+        }
+        unsigned char c = a[i] ^ b[i];
+        unsigned int count = 0;
+        for (; c; count++) {
+            c &= c - 1;
+        }
+        hamming += count;
+    }
+
+    return hamming;
+}

src/macos.c

@@ -1,6 +1,7 @@
 #include <libproc.h>
 #include <time.h>
 #include <mach/mach_time.h>
+#include <sys/errno.h>
 #include <stdlib.h>
 
 #include "lfmacos.h"
@@ -43,3 +44,39 @@ int update_process(pid_t pid, ProcessData *proc) {
 
     return 0;
 }
+
+/* reallocarray is reimplemented here for macOS because Apple doesn't expose
+ * their implementation. This is taken straight from the OpenBSD source as
+ * shown in the below copyright notice
+ */
+
+/*	$OpenBSD: reallocarray.c,v 1.2 2014/12/08 03:45:00 bcook Exp $	*/
+/*
+ * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* OPENBSD ORIGINAL: lib/libc/stdlib/reallocarray.c */
+
+#define MUL_NO_OVERFLOW	((size_t)1 << (sizeof(size_t) * 4))
+
+void *reallocarray(void *optr, size_t nmemb, size_t size)
+{
+    if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+        nmemb > 0 && SIZE_MAX / nmemb < size) {
+        errno = ENOMEM;
+        return NULL;
+    }
+    return realloc(optr, size * nmemb);
+}

src/vector.c

@@ -5,6 +5,10 @@
 #include <bsd/stdlib.h>
 #endif
 
+#if defined(__APPLE__) || defined(__MACH__)
+#include "lfmacos.h"
+#endif
+
 #include "lfvector.h"
 
 #define VEC_INIT_CAP 2
@@ -32,11 +36,7 @@ int vec_init_with_capacity(Vector *vec, void (*destroy)(void *data), size_t capa
 static int vec_grow(Vector *const vec) {
     vec->capacity *= 2;
 
-#ifdef __OpenBSD__
     vec->elements = reallocarray(vec->elements, vec->capacity, sizeof(void *));
-#else
-    vec->elements = reallocf(vec->elements, sizeof(void *) * vec->capacity);
-#endif
 
     if (vec->elements == NULL) {
         return -1;

tests/tests.c

@@ -349,6 +349,13 @@ void test_crypto() {
     }
     free(s);
 
+    // leading 0x
+    s = hex_decode("0xf00f5", &s_sz);
+    for (size_t i = 0; i < 3; ++i) {
+        assert(s[i] == h2[i]);
+    }
+    free(s);
+
     s = hex_encode(h, 4);
     assert(strcmp(s, "deadbeef") == 0);
     free(s);
@@ -367,6 +374,14 @@ void test_crypto() {
     free(enc);
     free(s);
 
+    unsigned char ua[2] = { 0x2, 0xF };
+    unsigned char ub[2] = { 0x4, 0xE };
+    unsigned int hamming = hamming_distance(ua, ub, 2);
+    assert(hamming == 3);
+
+    hamming = hamming_distance_s("this is a test", "wokka wokka!!!");
+    assert(hamming == 37);
+
     printf("Passes all crypto tests\n");
 }