Merge pull request #12 from Zachareee/dev

Updated for v2 hashes

.gitignore

@@ -3,3 +3,4 @@ hashes.sha1
 *.swp
 checksum.txt
 *.o
+SHA1check*

compare.c

@@ -10,36 +10,67 @@
 #include "paths.h"
 #define LINELEN 128
 
-regex_t reghex;
+regex_t reghex1;
+regex_t reghex2;
 
 // init regex sequences
 void regex_init() {
-    int regh = regcomp(&reghex, "[0-9a-fA-F]{40}", REG_EXTENDED);
-    if (regh) {
+    int regh1 = regcomp(&reghex1, "[0-9a-fA-F]{40}", REG_EXTENDED);
+    int regh2 = regcomp(&reghex2, "[0-9a-fA-F]{10}\\*\\*\\*[0-9a-fA-F]{10}", REG_EXTENDED);
+    if (regh1 | regh2) {
         printf("Something went wrong while initialising pattern matcher\n");
         exit(-2);
     }
 }
 
+// if full hash given, return 1
+// if partial hash given in the form of reghex2, returns 2
+// if unknown, return 0
+int get_hash_ver(char *line) {
+    if (!regexec(&reghex1, line, 0, NULL, 0)) return 1;
+    if (!regexec(&reghex2, line, 0, NULL, 0)) return 2;
+    return 0;
+}
+
 // trim trailing whitespaces in the line
 void trim(char *line, int offset) {
     for (int i = offset - 1; line[i] == ' ' || line[i] == '\t'; i--) {
         line[i] = 0;
     }
 }
 
+// obfuscates hash
+void obf_hash(char *line, char *result) {
+    strncpy(result, line, 10);
+    strncpy(result + 10, "***", 3);
+    strncpy(result + 13, line + 30, 10);
+}
+
 // compare hash of file against recorded hash
 // returns -1 if no hash found, -2 if file not found
 // 0 if hashsum equal and positive if strcmp fails
-int compare(char *dir, char *line) {
-    regmatch_t pmatch[1];
+int compare(char *dir, char *line, int ver) {
+    long result;
+    char *hash_value;
     char hex[41];
-    hex[40] = 0;
+    regmatch_t pmatch[1];
+    int limit;
+    regex_t *reg;
+
+    if (ver == 1) {
+        limit = 40;
+        reg = &reghex1;
+    } else {
+        limit = 23;
+        reg = &reghex2;
+    }
+
+    hex[limit] = 0;
 
     // find hexstring and copy to hex, return -1 if no matches
-    int match = regexec(&reghex, line, 1, pmatch, 0);
+    int match = regexec(reg, line, 1, pmatch, 0);
     if (match) return -1;
-    strncpy(hex, line + pmatch[0].rm_so, 40);
+    strncpy(hex, line + pmatch[0].rm_so, limit);
 
     // trim line to find file
     trim(line, pmatch[0].rm_so);
@@ -56,8 +87,20 @@ int compare(char *dir, char *line) {
     struct stat s;
     stat(path, &s);
 
-    char *hash_value = hash(path, s.st_size);
-    int result = strcmp(hash_value, hex);
+    hash_value = hash(path, s.st_size);
+
+    if (ver == 1) {
+        result = (long) strcmp(hash_value, hex);
+    } else {
+        long size;
+        sscanf(line + pmatch[0].rm_eo, "%ld", &size);
+
+        char temp[24];
+        obf_hash(hash_value, temp);
+        result = (long) strcmp(temp, hex);
+        result |= s.st_size - size;
+    }
+
     fprintf(stderr, "OK\n");
 
     // free malloc-ed variables
@@ -67,5 +110,6 @@ int compare(char *dir, char *line) {
 
 // frees regex allocs
 void free_regex() {
-    regfree(&reghex);
+    regfree(&reghex1);
+    regfree(&reghex2);
 }

headers/compare.h

@@ -1,3 +1,4 @@
-int compare(char *dir, char *line);
+int compare(char *dir, char *line, int version);
 void regex_init();
 void free_regex();
+int get_hash_ver(char *line);

main.c

@@ -45,9 +45,24 @@ int main(int argc, char **argv) {
     regex_init();
 
     FILE *hashfile = fopen(src, "r");
+
+    int version = 0;
+    char *line;
+    while ((line = get_line(hashfile)) && !version) {
+        version = get_hash_ver(line);
+        free(line);
+        if (version) goto ver;
+    }
+
+    printf("Could not find hashsum version, exiting...\n");
+    return -5;
+
+    ver:
+
+    fprintf(stderr, "Version %d hashfile detected\n", version);
+    fseek(hashfile, 0, SEEK_SET);
     FILE *checkfile = fopen(dst, "w");
 
-    char *line = get_line(hashfile);
     char ptr[PATH_MAX];
     char *state;
     // 0: OK, 1: MISSING, 2: FAILED, 3: EXTRA
@@ -58,12 +73,10 @@ int main(int argc, char **argv) {
     failed = calloc(1, sizeof(dir_t));
     extra = calloc(1, sizeof(dir_t));
 
-    while (line) {
+    while ((line = get_line(hashfile))) {
         strcpy(ptr, line);
         free(line);
-        int c = compare(dir, ptr);
-
-        line = get_line(hashfile);
+        int c = compare(dir, ptr, version);
 
         if (c == -1) continue;