Revamped to handle conversion both back and forth between V4 and V5 names

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@2551 dc483132-0cff-0310-8789-dd5450dbe970

diff --git a/src/lib/krb5/krb/conv_princ.c b/src/lib/krb5/krb/conv_princ.c
index 0edb170f5415bc5e4f5f00043960d79c42f7cdbb..5149457c8c2f8e46f444c732ce210b9614291224 100644 (file)
--- a/src/lib/krb5/krb/conv_princ.c
+++ b/src/lib/krb5/krb/conv_princ.c
@@ -21,8 +21,8 @@
  * this software for any purpose.  It is provided "as is" without express
  * or implied warranty.
  * 
- *
- * Build a principal from a V4 specification
+ * Build a principal from a V4 specification, or separate a V5
+ * principal into name, instance, and realm.
  * 
  * NOTE: This is highly site specific, and is only really necessary
  * for sites who need to convert from V4 to V5.  It is used by both
@@ -34,6 +34,13 @@
 #include <krb5/krb5.h>
 #include <string.h>
 
+/* The maximum sizes for V4 aname, realm, sname, and instance +1 */
+/* Taken from krb.h */
+#define        ANAME_SZ        40
+#define                REALM_SZ        40
+#define                SNAME_SZ        40
+#define                INST_SZ         40
+
 struct krb_convert {
        char    *v4_str;
        char    *v5_str;
@@ -65,47 +72,144 @@ static struct krb_convert rconv_list[] = {
        0,                      0
 };
 
-krb5_error_code
-krb5_425_conv_principal(name, instance, realm, princ)
-    const char *name;
-    const char *instance;
-    const char *realm;
-    krb5_principal     *princ;
+/*
+ * char *strnchr(s, c, n)
+ *   char *s;
+ *   char c;
+ *   int n;
+ *
+ * returns a pointer to the first occurrence of character c in the
+ * string s, or a NULL pointer if c does not occur in in the string;
+ * however, at most the first n characters will be considered.
+ *
+ * This falls in the "should have been in the ANSI C library"
+ * category. :-)
+ */
+static char *strnchr(s, c, n)
+   register char *s, c;
+   register int n;
 {
-    struct krb_convert *p;
-    char buf[256];             /* V4 instances are limited to 40 characters */
-               
-    if (instance) {
-       if (instance[0] == '\0') {
-           instance = 0;
-           goto not_service;
-       }
-       p = sconv_list;
-       while (1) {
-           if (!p->v4_str)
-               goto not_service;
-           if (!strcmp(p->v4_str, name))
-               break;
-           p++;
-       }
-       name = p->v5_str;
-       if (p->flags & DO_REALM_CONVERSION) {
-           strcpy(buf, instance);
-           p = rconv_list;
-           while (1) {
-               if (!p->v4_str)
-                   break;
-               if (!strcmp(p->v4_str, realm))
+     if (n < 1) 
+         return 0;
+     
+     while (n-- && *s) {
+         if (*s == c)
+              return s;
+         s++;
+     }
+     return 0;
+}
+
+
+/* XXX This calls for a new error code */
+#define KRB5_INVALID_PRINCIPAL KRB5_LNAME_BADFORMAT
+
+krb5_error_code krb5_524_conv_principal(princ, name, inst, realm)
+   const krb5_principal princ;
+   char *name;
+   char *inst;
+   char *realm;
+{
+     struct krb_convert *p;
+     krb5_data *comp;
+     char *c;
+
+     *name = *inst = '\0';
+     switch (krb5_princ_size(princ)) {
+     case 2:
+         /* Check if this principal is listed in the table */
+         comp = krb5_princ_component(princ, 0);
+         p = sconv_list;
+         while (p->v4_str) {
+              if (strncmp(p->v5_str, comp->data, comp->length) == 0) {
+                   /* It is, so set the new name now, and chop off */
+                   /* instance's domain name if requested */
+                   strcpy(name, p->v4_str);
+                   if (p->flags & DO_REALM_CONVERSION) {
+                        comp = krb5_princ_component(princ, 1);
+                        c = strnchr(comp->data, '.', comp->length);
+                        if (!c || (c - comp->data) > INST_SZ - 1)
+                             return KRB5_INVALID_PRINCIPAL;
+                        strncpy(inst, comp->data, c - comp->data);
+                        inst[c - comp->data] = '\0';
+                   }
                    break;
-               p++;
-           }
-           if (p->v5_str)
-               strcat(buf, p->v5_str);
-           instance = buf;
-       }
-       }
+              }
+              p++;
+         }
+         /* If inst isn't set, the service isn't listed in the table, */
+         /* so just copy it. */
+         if (*inst == '\0') {
+              comp = krb5_princ_component(princ, 1);
+              if (comp->length >= INST_SZ - 1)
+                   return KRB5_INVALID_PRINCIPAL;
+              strncpy(inst, comp->data, comp->length);
+              inst[comp->length] = '\0';
+         }
+         /* fall through */
+     case 1:
+         /* name may have been set above; otherwise, just copy it */
+         if (*name == '\0') {
+              comp = krb5_princ_component(princ, 0);
+              if (comp->length >= ANAME_SZ)
+                   return KRB5_INVALID_PRINCIPAL;
+              strncpy(name, comp->data, comp->length);
+              name[comp->length] = '\0';
+         }
+         break;
+     default:
+         return KRB5_INVALID_PRINCIPAL;
+     }
 
-    not_service:       
-       return(krb5_build_principal(princ, strlen(realm), realm, name,
-                                   instance, 0));
-    }
+     comp = krb5_princ_realm(princ);
+     if (comp->length > REALM_SZ - 1)
+         return KRB5_INVALID_PRINCIPAL;
+     strncpy(realm, comp->data, comp->length);
+     realm[comp->length] = '\0';
+
+     return 0;
+}
+
+krb5_error_code krb5_425_conv_principal(name, instance, realm, princ)
+   const char  *name;
+   const char  *instance;
+   const char  *realm;
+   krb5_principal      *princ;
+{
+     struct krb_convert *p;
+     char buf[256];            /* V4 instances are limited to 40 characters */
+     
+     if (instance) {
+         if (instance[0] == '\0') {
+              instance = 0;
+              goto not_service;
+         }
+         p = sconv_list;
+         while (1) {
+              if (!p->v4_str)
+                   goto not_service;
+              if (!strcmp(p->v4_str, name))
+                   break;
+              p++;
+         }
+         name = p->v5_str;
+         if (p->flags & DO_REALM_CONVERSION) {
+              strcpy(buf, instance);
+              p = rconv_list;
+              while (1) {
+                   if (!p->v4_str)
+                        break;
+                   if (!strcmp(p->v4_str, realm))
+                        break;
+                   p++;
+              }
+              if (p->v5_str)
+                   strcat(buf, p->v5_str);
+              instance = buf;
+         }
+     }
+     
+not_service:   
+     return(krb5_build_principal(princ, strlen(realm), realm, name,
+                                instance, 0));
+}