Update redis_ippool to allow for static IP allocation

Static allocations are defined by a ZSCORE with bit 52 set in the <pool_name>:pool ZSET and pre-created entries in the <pool_name>:ip:<address> hash and <pool_name>:device:<owner> key

diff --git a/src/modules/rlm_redis_ippool/redis_ippool.h b/src/modules/rlm_redis_ippool/redis_ippool.h
index 181cdfb2e7cfed84ff079939684effc289c27576..063751981e2a88b8790d777bf2b560c408378e77 100644 (file)
--- a/src/modules/rlm_redis_ippool/redis_ippool.h
+++ b/src/modules/rlm_redis_ippool/redis_ippool.h
@@ -57,6 +57,7 @@ typedef enum {
 #define IPPOOL_POOL_KEY                        "pool"
 #define IPPOOL_ADDRESS_KEY             "ip"
 #define IPPOOL_OWNER_KEY               "device"
+#define IPPOOL_STATIC_BIT              0x10000000000000   /* A high bit which Redis ZSCORE will represent accurately*/
 
 /** {prefix}:pool
  */

diff --git a/src/modules/rlm_redis_ippool/rlm_redis_ippool.c b/src/modules/rlm_redis_ippool/rlm_redis_ippool.c
index 85c120c84efd8a4d887a0d8b41af5a72aa49a092..dd6ad68b0e55e0f955dc9d91f227a2767b190290 100644 (file)
--- a/src/modules/rlm_redis_ippool/rlm_redis_ippool.c
+++ b/src/modules/rlm_redis_ippool/rlm_redis_ippool.c
@@ -211,14 +211,23 @@ static char lua_alloc_cmd[] =
         */
        "exists = redis.call('GET', owner_key);" EOL                                                    /* 8 */
        "if exists then" EOL                                                                            /* 9 */
-       "  local expires_in = tonumber(redis.call('ZSCORE', pool_key, exists) - ARGV[1])" EOL           /* 10 */
-       "  if expires_in > 0 then" EOL                                                                  /* 11 */
-       "    ip = redis.call('HMGET', '{' .. KEYS[1] .. '}:"IPPOOL_ADDRESS_KEY":' .. exists, 'device', 'range', 'counter')" EOL /* 12 */
+       "  local expires = tonumber(redis.call('ZSCORE', pool_key, exists))" EOL                        /* 10 */
+       "  local static = expires >= " STRINGIFY(IPPOOL_STATIC_BIT) EOL
+       "  local expires_in = expires - (static and " STRINGIFY(IPPOOL_STATIC_BIT) " or 0) - ARGV[1]" EOL
+       "  if expires_in > 0 or static then" EOL                                                        /* 11 */
+       "    ip = redis.call('HMGET', '{' .. KEYS[1] .. '}:"IPPOOL_ADDRESS_KEY":' .. exists, 'device', 'range', 'counter', 'gateway')" EOL      /* 12 */
        "    if ip and (ip[1] == ARGV[3]) then" EOL                                                     /* 13 */
        "      if expires_in < tonumber(ARGV[2]) then" EOL                                              /* 14 */
-       "        redis.call('ZADD', pool_key, 'XX', ARGV[1] + ARGV[2], exists)" EOL                     /* 15 */
+       "        redis.call('ZADD', pool_key, 'XX', ARGV[1] + ARGV[2] + (static and " STRINGIFY(IPPOOL_STATIC_BIT) " or 0), exists)" EOL        /* 15 */
        "        expires_in = tonumber(ARGV[2])" EOL                                                    /* 16 */
        "      end" EOL                                                                                 /* 17 */
+
+       /*
+        *      Ensure gateway is set correctly
+        */
+       "      if ARGV[4] ~= ip[4] then" EOL
+       "        redis.call('HSET', '{' .. KEYS[1] .. '}:"IPPOOL_ADDRESS_KEY":', 'gateway', ARGV[4])" EOL
+       "      end" EOL
        "      return {" STRINGIFY(_IPPOOL_RCODE_SUCCESS) ", exists, ip[2], expires_in, ip[3] }" EOL    /* 18 */
        "    end" EOL                                                                                   /* 19 */
        "  end" EOL                                                                                     /* 20 */
@@ -295,7 +304,9 @@ static char lua_update_cmd[] =
         *      Update the expiry time
         */
        "pool_key = '{' .. KEYS[1] .. '}:"IPPOOL_POOL_KEY"'" EOL                        /* 14 */
-       "redis.call('ZADD', pool_key, 'XX', ARGV[1] + ARGV[2], ARGV[3])" EOL            /* 15 */
+       "local expires = tonumber(redis.call('ZSCORE', pool_key, ARGV[3]))" EOL
+       "local static = expires > " STRINGIFY(IPPOOL_STATIC_BIT) EOL
+       "redis.call('ZADD', pool_key, 'XX', ARGV[1] + ARGV[2] + (static and " STRINGIFY(IPPOOL_STATIC_BIT) " or 0), ARGV[3])" EOL       /* 15 */
 
        /*
         *      The device key should usually exist, but
@@ -303,8 +314,8 @@ static char lua_update_cmd[] =
         *      of a lease being expired, it may have been
         *      removed.
         */
-       "owner_key = '{' .. KEYS[1] .. '}:"IPPOOL_OWNER_KEY":' .. ARGV[4]" EOL  /* 16 */
-       "if redis.call('EXPIRE', owner_key, ARGV[2]) == 0 then" EOL                     /* 17 */
+       "owner_key = '{' .. KEYS[1] .. '}:"IPPOOL_OWNER_KEY":' .. ARGV[4]" EOL          /* 16 */
+       "if not static and (redis.call('EXPIRE', owner_key, ARGV[2]) == 0) then" EOL    /* 17 */
        "  redis.call('SET', owner_key, ARGV[3])" EOL                                   /* 18 */
        "  redis.call('EXPIRE', owner_key, ARGV[2])" EOL                                /* 19 */
        "end" EOL                                                                       /* 20 */
@@ -355,16 +366,19 @@ static char lua_release_cmd[] =
        "end" EOL                                                                       /* 14 */
 
        /*
-        *      Set expiry time to now() - 1
+        *      Set expiry time to now() - 1 if it is not static
         */
        "pool_key = '{' .. KEYS[1] .. '}:"IPPOOL_POOL_KEY"'" EOL                        /* 15 */
-       "redis.call('ZADD', pool_key, 'XX', ARGV[1] - 1, ARGV[2])" EOL                  /* 16 */
+       "found = tonumber(redis.call('ZSCORE', pool_key, ARGV[2]))" EOL
+       "if found < " STRINGIFY(IPPOOL_STATIC_BIT) " then" EOL
+       "  redis.call('ZADD', pool_key, 'XX', ARGV[1] - 1, ARGV[2])" EOL                /* 16 */
 
        /*
         *      Remove the association between the device and a lease
         */
-       "owner_key = '{' .. KEYS[1] .. '}:"IPPOOL_OWNER_KEY":' .. ARGV[3]" EOL  /* 17 */
-       "redis.call('DEL', owner_key)" EOL                                              /* 18 */
+       "  owner_key = '{' .. KEYS[1] .. '}:"IPPOOL_OWNER_KEY":' .. ARGV[3]" EOL        /* 17 */
+       "  redis.call('DEL', owner_key)" EOL                                            /* 18 */
+       "end" EOL
        "return { " EOL
        "  " STRINGIFY(_IPPOOL_RCODE_SUCCESS) "," EOL                                   /* 19 */
        "  redis.call('HINCRBY', address_key, 'counter', 1) - 1" EOL                    /* 20 */