/* * Copyright (c) 2015 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* Copyright (c) 2001-2005 Eliot Dresselhaus Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #ifndef included_hash_h #define included_hash_h #include #include #include #include struct hash_header; typedef uword (hash_key_sum_function_t) (struct hash_header *, uword key); typedef uword (hash_key_equal_function_t) (struct hash_header *, uword key1, uword key2); /* Vector header for hash tables. */ typedef struct hash_header { /* Number of elements in hash table. */ uword elts; /* Flags as follows. */ u32 flags; /* Set if user does not want table to auto-resize when sufficiently full. */ #define HASH_FLAG_NO_AUTO_GROW (1 << 0) /* Set if user does not want table to auto-resize when sufficiently empty. */ #define HASH_FLAG_NO_AUTO_SHRINK (1 << 1) /* Set when hash_next is in the process of iterating through this hash table. */ #define HASH_FLAG_HASH_NEXT_IN_PROGRESS (1 << 2) u32 log2_pair_size; /* Function to compute the "sum" of a hash key. Hash function is this sum modulo the prime size of the hash table (vec_len (v)). */ hash_key_sum_function_t *key_sum; /* Special values for key_sum "function". */ #define KEY_FUNC_NONE (0) /*< sum = key */ #define KEY_FUNC_POINTER_UWORD (1) /*< sum = *(uword *) key */ #define KEY_FUNC_POINTER_U32 (2) /*< sum = *(u32 *) key */ #define KEY_FUNC_STRING (3) /*< sum = string_key_sum, etc. */ #define KEY_FUNC_MEM (4) /*< sum = mem_key_sum */ /* key comparison function */ hash_key_equal_function_t *key_equal; /* Hook for user's data. Used to parameterize sum/equal functions. */ any user; /* Format a (k,v) pair */ format_function_t *format_pair; /* Format function arg */ void *format_pair_arg; /* Bit i is set if pair i is a user object (as opposed to being either zero or an indirect array of pairs). */ uword is_user[0]; } hash_t; /* Hash header size in bytes */ always_inline uword hash_header_bytes (void *v) { hash_t *h; uword is_user_bytes = (sizeof (h->is_user[0]) * vec_len (v)) / BITS (h->is_user[0]); return sizeof (h[0]) + is_user_bytes; } /* Returns a pointer to the hash header given the vector pointer */ always_inline hash_t * hash_header (void *v) { return vec_header (v, hash_header_bytes (v)); } /* Number of elements in the hash table */ always_inline uword hash_elts (void *v) { hash_t *h = hash_header (v); return v ? h->elts : 0; } /* Number of elements the hash table can hold */ always_inline uword hash_capacity (void *v) { return vec_len (v); } /* Returns 1 if the hash pair contains user data */ always_inline uword hash_is_user (void *v, uword i) { hash_t *h = hash_header (v); uword i0 = i / BITS (h->is_user[0]); uword i1 = i % BITS (h->is_user[0]); return (h->is_user[i0] & ((uword) 1 << i1)) != 0; } /* Set the format function and format argument for a hash table */ always_inline void hash_set_pair_format (void *v, format_function_t * format_pair, void *format_pair_arg) { hash_t *h = hash_header (v); h->format_pair = format_pair; h->format_pair_arg = format_pair_arg; } /* Set hash table flags */ always_inline void hash_set_flags (void *v, uword flags) { hash_header (v)->flags |= flags; } /* Key value pairs. */ typedef struct { /* The Key */ uword key; /* The Value. Length is 2^log2_pair_size - 1. */ uword value[0]; } hash_pair_t; /* The indirect pair structure If log2_pair_size > 0 we overload hash pairs with indirect pairs for buckets with more than one pair. */ typedef struct { /* pair vector */ hash_pair_t *pairs; /* padding */ u8 pad[sizeof (uword) - sizeof (hash_pair_t *)]; /* allocated length */ uword alloc_len; } hash_pair_indirect_t; /* Direct / Indirect pair union */ typedef union { hash_pair_t direct; hash_pair_indirect_t indirect; } hash_pair_union_t; #define LOG2_ALLOC_BITS (5) #define PAIR_BITS (BITS (uword) - LOG2_ALLOC_BITS) /* Log2 number of bytes allocated in pairs array. */ always_inline uword indirect_pair_get_log2_bytes (hash_pair_indirect_t * p) { return p->alloc_len >> PAIR_BITS; } /* Get the length of an indirect pair */ always_inline uword indirect_pair_get_len (hash_pair_indirect_t * p) { if (!p->pairs) return 0; else return p->alloc_len & (((uword) 1 << PAIR_BITS) - 1); } /* Set the length of an indirect pair */ always_inline void indirect_pair_set (hash_pair_indirect_t * p, uword log2_alloc, uword len) { ASSERT (len < ((uword) 1 << PAIR_BITS)); ASSERT (log2_alloc < ((uword) 1 << LOG2_ALLOC_BITS)); p->alloc_len = (log2_alloc << PAIR_BITS) | len; } /* internal routine to fetch value for given key */ uword *_hash_get (void *v, uword key); /* internal routine to fetch value (key, value) pair for given key */ hash_pair_t *_hash_get_pair (void *v, uword key); /* internal routine to unset a (key, value) pair */ void *_hash_unset (void *v, uword key, void *old_value); /* internal routine to set a (key, value) pair, return the old value */ void *_hash_set3 (void *v, uword key, void *value, void *old_value); /* Resize a hash table */ void *hash_resize (void *old, uword new_size); /* duplicate a hash table */ void *hash_dup (void *old); /* Returns the number of bytes used by a hash table */ uword hash_bytes (void *v); /* Public macro to set a (key, value) pair, return the old value */ #define hash_set3(h,key,value,old_value) \ ({ \ uword _v = (uword) (value); \ (h) = _hash_set3 ((h), (uword) (key), (void *) &_v, (old_value)); \ }) /* Public macro to fetch value for given key */ #define hash_get(h,key) _hash_get ((h), (uword) (key)) /* Public macro to fetch value (key, value) pair for given key */ #define hash_get_pair(h,key) _hash_get_pair ((h), (uword) (key)) /* Public macro to set a (key, value) pair */ #define hash_set(h,key,value) hash_set3(h,key,value,0) /* Public macro to set (key, 0) pair */ #define hash_set1(h,key) (h) = _hash_set3(h,(uword) (key),0,0) /* Public macro to unset a (key, value) pair */ #define hash_unset(h,key) ((h) = _hash_unset ((h), (uword) (key),0)) /* Public macro to unset a (key, value) pair, return the old value */ #define hash_unset3(h,key,old_value) ((h) = _hash_unset ((h), (uword) (key), (void *) (old_value))) /* get/set/unset for pointer keys. */ /* Public macro to fetch value for given pointer key */ #define hash_get_mem(h,key) _hash_get ((h), pointer_to_uword (key)) /* Public macro to fetch (key, value) for given pointer key */ #define hash_get_pair_mem(h,key) _hash_get_pair ((h), pointer_to_uword (key)) /* Public macro to set (key, value) for pointer key */ #define hash_set_mem(h,key,value) hash_set3 (h, pointer_to_uword (key), (value), 0) /* Public inline function allocate and copy key to use in hash for pointer key */ always_inline void hash_set_mem_alloc (uword ** h, void *key, uword v) { size_t ksz = hash_header (*h)->user; void *copy = clib_mem_alloc (ksz); clib_memcpy_fast (copy, key, ksz); hash_set_mem (*h, copy, v); } /* Public macro to set (key, 0) for pointer key */ #define hash_set1_mem(h,key) hash_set3 ((h), pointer_to_uword (key), 0, 0) /* Public macro to unset (key, value) for pointer key */ #define hash_unset_mem(h,key) ((h) = _hash_unset ((h), pointer_to_uword (key),0)) /* Public inline function to unset pointer key and then free the key memory */ always_inline void hash_unset_mem_free (uword ** h, void *key) { hash_pair_t *hp = hash_get_pair_mem (*h, key); if (PREDICT_TRUE (hp != NULL)) { key = uword_to_pointer (hp->key, void *); hash_unset_mem (*h, key); clib_mem_free (key); } } /* internal routine to free a hash table */ extern void *_hash_free (void *v); /* Public macro to free a hash table */ #define hash_free(h) (h) = _hash_free ((h)) clib_error_t *hash_validate (void *v); /* Public inline function to get the number of value bytes for a hash table */ always_inline uword hash_value_bytes (hash_t * h) { hash_pair_t *p; return (sizeof (p->value[0]) << h->log2_pair_size) - sizeof (p->key); } /* Public inline function to get log2(size of a (key,value) pair) */ always_inline uword hash_pair_log2_bytes (hash_t * h) { uword log2_bytes = h->log2_pair_size; ASSERT (BITS (hash_pair_t) == 32 || BITS (hash_pair_t) == 64); if (BITS (hash_pair_t) == 32) log2_bytes += 2; else if (BITS (hash_pair_t) == 64) log2_bytes += 3; return log2_bytes; } /* Public inline function to get size of a (key,value) pair */ always_inline uword hash_pair_bytes (hash_t * h) { return (uword) 1 << hash_pair_log2_bytes (h); } /* Public inline function to advance a pointer past one (key,value) pair */ always_inline void * hash_forward1 (hash_t * h, void *v) { return (u8 *) v + hash_pair_bytes (h); } /* Public inline function to advance a pointer past N (key,value) pairs */ always_inline void * hash_forward (hash_t * h, void *v, uword n) { return (u8 *) v + ((n * sizeof (hash_pair_t)) << h->log2_pair_size); } /** Iterate over hash pairs. @param p The current (key,value) pair. This should be of type (hash_pair_t *). @param v The hash table to iterate. @param body The operation to perform on each (key,value) pair. Executes the expression or code block @c body with each active hash pair. */ /* A previous version of this macro made use of the hash_pair_union_t * structure; this version does not since that approach mightily upset * the static analysis tool. In the rare chance someone is reading this * code, pretend that _p below is of type hash_pair_union_t and that when * used as an rvalue it's really using one of the union members as the * rvalue. If you were confused before you might be marginally less * confused after. */ #define hash_foreach_pair(p,v,body) \ do { \ __label__ _hash_foreach_done; \ hash_t * _h = hash_header (v); \ void * _p; \ hash_pair_t * _q, * _q_end; \ uword _i, _i1, _id, _pair_increment; \ \ _p = (v); \ _i = 0; \ _pair_increment = 1; \ if ((v)) \ _pair_increment = 1 << _h->log2_pair_size; \ while (_i < hash_capacity (v)) \ { \ _id = _h->is_user[_i / BITS (_h->is_user[0])]; \ _i1 = _i + BITS (_h->is_user[0]); \ \ do { \ if (_id & 1) \ { \ _q = _p; \ _q_end = _q + _pair_increment; \ } \ else \ { \ hash_pair_indirect_t * _pi = _p; \ _q = _pi->pairs; \ if (_h->log2_pair_size > 0) \ _q_end = hash_forward (_h, _q, indirect_pair_get_len (_pi)); \ else \ _q_end = vec_end (_q); \ } \ \ /* Loop through all elements in bucket. \ Bucket may have 0 1 or more (indirect case) pairs. */ \ while (_q < _q_end) \ { \ uword _break_in_body = 1; \ (p) = _q; \ do { \ body; \ _break_in_body = 0; \ } while (0); \ if (_break_in_body) \ goto _hash_foreach_done; \ _q += _pair_increment; \ } \ \ _p = (hash_pair_t *)_p + _pair_increment; \ _id = _id / 2; \ _i++; \ } while (_i < _i1); \ } \ _hash_foreach_done: \ /* Be silent Mr. Compiler-Warning. */ \ ; \ } while (0) /* Iterate over key/value pairs @param key_var the current key @param value_var the current value @param h the hash table to iterate across @param body the operation to perform on each (key_var,value_var) pair. calls body with each active hash pair */ /* Iterate over key/value pairs. */ #define hash_foreach(key_var,value_var,h,body) \ do { \ hash_pair_t * _r; \ hash_foreach_pair (_r, (h), { \ (key_var) = (__typeof__ (key_var)) _r->key; \ (value_var) = (__typeof__ 
/*
 * proxy_node.c: common dhcp v4 and v6 proxy node processing
 *
 * Copyright (c) 2013 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOU