apparmor: dfa move character match into a macro

Signed-off-by: John Johansen <john.johansen@canonical.com>

diff --git a/security/apparmor/match.c b/security/apparmor/match.c
index 5d95caeddebc09a966fb2a86aea4aaa7c1bf5051..aeac68c58689ef45b40d27165e405b884ee2217f 100644 (file)
--- a/security/apparmor/match.c
+++ b/security/apparmor/match.c
@@ -329,6 +329,18 @@ fail:
        return ERR_PTR(error);
 }
 
+#define match_char(state, def, base, next, check, C)   \
+do {                                                   \
+       u32 b = (base)[(state)];                        \
+       unsigned int pos = base_idx(b) + (C);           \
+       if ((check)[pos] != (state)) {                  \
+               (state) = (def)[(state)];               \
+               break;                                  \
+       }                                               \
+       (state) = (next)[pos];                          \
+       break;                                          \
+} while (1)
+
 /**
  * aa_dfa_match_len - traverse @dfa to find state @str stops at
  * @dfa: the dfa to match @str against  (NOT NULL)
@@ -352,7 +364,7 @@ unsigned int aa_dfa_match_len(struct aa_dfa *dfa, unsigned int start,
        u32 *base = BASE_TABLE(dfa);
        u16 *next = NEXT_TABLE(dfa);
        u16 *check = CHECK_TABLE(dfa);
-       unsigned int state = start, pos;
+       unsigned int state = start;
 
        if (state == 0)
                return 0;
@@ -361,23 +373,13 @@ unsigned int aa_dfa_match_len(struct aa_dfa *dfa, unsigned int start,
        if (dfa->tables[YYTD_ID_EC]) {
                /* Equivalence class table defined */
                u8 *equiv = EQUIV_TABLE(dfa);
-               /* default is direct to next state */
-               for (; len; len--) {
-                       pos = base_idx(base[state]) + equiv[(u8) *str++];
-                       if (check[pos] == state)
-                               state = next[pos];
-                       else
-                               state = def[state];
-               }
+               for (; len; len--)
+                       match_char(state, def, base, next, check,
+                                  equiv[(u8) *str++]);
        } else {
                /* default is direct to next state */
-               for (; len; len--) {
-                       pos = base_idx(base[state]) + (u8) *str++;
-                       if (check[pos] == state)
-                               state = next[pos];
-                       else
-                               state = def[state];
-               }
+               for (; len; len--)
+                       match_char(state, def, base, next, check, (u8) *str++);
        }
 
        return state;
@@ -402,7 +404,7 @@ unsigned int aa_dfa_match(struct aa_dfa *dfa, unsigned int start,
        u32 *base = BASE_TABLE(dfa);
        u16 *next = NEXT_TABLE(dfa);
        u16 *check = CHECK_TABLE(dfa);
-       unsigned int state = start, pos;
+       unsigned int state = start;
 
        if (state == 0)
                return 0;
@@ -412,22 +414,13 @@ unsigned int aa_dfa_match(struct aa_dfa *dfa, unsigned int start,
                /* Equivalence class table defined */
                u8 *equiv = EQUIV_TABLE(dfa);
                /* default is direct to next state */
-               while (*str) {
-                       pos = base_idx(base[state]) + equiv[(u8) *str++];
-                       if (check[pos] == state)
-                               state = next[pos];
-                       else
-                               state = def[state];
-               }
+               while (*str)
+                       match_char(state, def, base, next, check,
+                                  equiv[(u8) *str++]);
        } else {
                /* default is direct to next state */
-               while (*str) {
-                       pos = base_idx(base[state]) + (u8) *str++;
-                       if (check[pos] == state)
-                               state = next[pos];
-                       else
-                               state = def[state];
-               }
+               while (*str)
+                       match_char(state, def, base, next, check, (u8) *str++);
        }
 
        return state;
@@ -450,27 +443,14 @@ unsigned int aa_dfa_next(struct aa_dfa *dfa, unsigned int state,
        u32 *base = BASE_TABLE(dfa);
        u16 *next = NEXT_TABLE(dfa);
        u16 *check = CHECK_TABLE(dfa);
-       unsigned int pos;
 
        /* current state is <state>, matching character *str */
        if (dfa->tables[YYTD_ID_EC]) {
                /* Equivalence class table defined */
                u8 *equiv = EQUIV_TABLE(dfa);
-               /* default is direct to next state */
-
-               pos = base_idx(base[state]) + equiv[(u8) c];
-               if (check[pos] == state)
-                       state = next[pos];
-               else
-                       state = def[state];
-       } else {
-               /* default is direct to next state */
-               pos = base_idx(base[state]) + (u8) c;
-               if (check[pos] == state)
-                       state = next[pos];
-               else
-                       state = def[state];
-       }
+               match_char(state, def, base, next, check, equiv[(u8) c]);
+       } else
+               match_char(state, def, base, next, check, (u8) c);
 
        return state;
 }