Clean up open_cred_file()

[Sent this to Jeff a bit ago and forgot to CC the mailing list - Scott]


Jeff, I agree on all of your points.  Good catch on the second memset(), 
too.
The patch below (and attached) has the changes you mentioned.

Also, for the sake of consistency and to keep the indentation sane, I've 
switched to the 'if(!temp_val) continue;' flow that was used for parsing 
one case but not the other two.





indicate
@@ -128,7 +128,7 @@ struct parsed_mount_info {
       char share[MAX_SHARE_LEN + 1];
       char prefix[PATH_MAX + 1];
       char options[MAX_OPTIONS_LEN];
-    char domain[DOMAIN_SIZE + 1];
+    char domain[MAX_DOMAIN_SIZE + 1];
       char username[MAX_USERNAME_SIZE + 1];
       char password[MOUNT_PASSWD_SIZE + 1];
       char addrlist[MAX_ADDR_LIST_LEN];
@@ -511,14 +511,26 @@ toggle_dac_capability(int writable, int enable)
   #endif /* HAVE_LIBCAP */
   #endif /* HAVE_LIBCAP_NG */

+/*
+ * Null terminates string at first '\n'.
+ */
+static void null_terminate_endl(char* source)
+{
+    char* newline = strchr(source, '\n');
+    if (newline)
+        *newline = '\0';
+}
+
   static int open_cred_file(char *file_name,
                 struct parsed_mount_info *parsed_info)
   {
       char *line_buf;
-    char *temp_val, *newline;
+    char *temp_val;
       FILE *fs = NULL;
-    int i, length;
-
+    int i;
+    const int line_buf_size = 4096;
+    const int min_non_white = 10;
+
       i = toggle_dac_capability(0, 1);
       if (i)
           return i;
@@ -541,86 +553,59 @@ static int open_cred_file(char *file_name,
           return i;
       }

-    line_buf = (char *)malloc(4096);
+    line_buf = (char *)malloc(line_buf_size);
       if (line_buf == NULL) {
           fclose(fs);
           return EX_SYSERR;
       }

-    while (fgets(line_buf, 4096, fs)) {
-        /* parse line from credential file */
-
+    /* parse line from credential file*/
+    while (fgets(line_buf, line_buf_size, fs)) {
           /* eat leading white space */
-        for (i = 0; i < 4086; i++) {
+        for (i = 0; i < line_buf_size - min_non_white + 1; i++) {
               if ((line_buf[i] != ' ') && (line_buf[i] != '\t'))
                   break;
-            /* if whitespace - skip past it */
           }
+        null_terminate_endl(line_buf);

-        /* NULL terminate at newline */
-        newline = strchr(line_buf + i, '\n');
-        if (newline)
-            *newline = '\0';
-
+        /* parse user */
           if (strncasecmp("user", line_buf + i, 4) == 0) {
               temp_val = strchr(line_buf + i, '=');
-            if (temp_val) {
-                /* go past equals sign */
-                temp_val++;
-                for (length = 0; length < 4087; length++) {
-                    if ((temp_val[length] == '\n')
-                        || (temp_val[length] == '\0')) {
-                        temp_val[length] = '\0';
-                        break;
-                    }
-                }
-                if (length > 4086) {
-                    fprintf(stderr,
-                        "mount.cifs failed due to malformed username in 
credentials file\n");
-                    memset(line_buf, 0, 4096);
-                    return EX_USAGE;
-                }
-                parsed_info->got_user = 1;
-                strlcpy(parsed_info->username, temp_val,
-                    sizeof(parsed_info->username));
-            }
-        } else if (strncasecmp("pass", line_buf + i, 4) == 0) {
+            if (!temp_val)
+                continue;
+            /* go past equals sign */
+            temp_val++;
+            parse_username(temp_val, parsed_info);
+            memset(line_buf, 0, line_buf_size);
+        }
+
+        /* parse password */
+        else if (strncasecmp("pass", line_buf + i, 4) == 0) {
               temp_val = strchr(line_buf + i, '=');
               if (!temp_val)
                   continue;
-            ++temp_val;
+                        /* go past equals sign */
+            temp_val++;
               i = set_password(parsed_info, temp_val);
+            /* zero out password from buffer */
+            memset(line_buf, 0, line_buf_size);
               if (i)
                   return i;
-        } else if (strncasecmp("dom", line_buf + i, 3) == 0) {
+        }
+
+        /* parse domain */
+        else if (strncasecmp("dom", line_buf + i, 3) == 0) {
               temp_val = strchr(line_buf + i, '=');
-            if (temp_val) {
-                /* go past equals sign */
-                temp_val++;
-                if (parsed_info->verboseflag)
-                    fprintf(stderr, "\nDomain %s\n",
-                        temp_val);
-
-                for (length = 0; length < DOMAIN_SIZE + 1;
-                     length++) {
-                    if ((temp_val[length] == '\n')
-                        || (temp_val[length] == '\0')) {
-                        temp_val[length] = '\0';
-                        break;
-                    }
-                }
-
-                if (length > DOMAIN_SIZE) {
-                    fprintf(stderr,
-                        "mount.cifs failed: domain in credentials file 
too long\n");
-                    return EX_USAGE;
-                }
-
-                strlcpy(parsed_info->domain, temp_val,
-                    sizeof(parsed_info->domain));
+            if (!temp_val)
+                continue;
+            /* go past equals sign */
+            temp_val++;
+            if (parsed_info->verboseflag)
+                fprintf(stderr, "\nDomain %s\n", temp_val);
+            strlcpy(parsed_info->domain, temp_val,
+                sizeof(parsed_info->domain));
               }
           }
-
       }
       fclose(fs);
       SAFE_FREE(line_buf);