5  * New keys are 'rotated' in two steps:
7  * 2) Make new key the primary by swapping the backup and primary keys
51 static void get_keys(int fd, uint32_t *keys)  in get_keys()  argument
57 		if (getsockopt(fd, SOL_TCP, TCP_FASTOPEN_KEY, keys, &len))  in get_keys()
64 	if (sscanf(buf, "%x-%x-%x-%x,%x-%x-%x-%x", keys, keys + 1, keys + 2,  in get_keys()
65 	    keys + 3, keys + 4, keys + 5, keys + 6, keys + 7) != 8)  in get_keys()
69 static void set_keys(int fd, uint32_t *keys)  in set_keys()  argument
74 		if (setsockopt(fd, SOL_TCP, TCP_FASTOPEN_KEY, keys,  in set_keys()
81 			 keys[0], keys[1], keys[2], keys[3], keys[4], keys[5],  in set_keys()
82 			 keys[6], keys[7]);  in set_keys()
85 			 keys[0], keys[1], keys[2], keys[3]);  in set_keys()
98 	uint32_t keys[8];  in build_rcv_fd()  local
123 	for (i = 0; i < ARRAY_SIZE(keys); i++)  in build_rcv_fd()
124 		keys[i] = rand();  in build_rcv_fd()
137 		set_keys(rcv_fds[i], keys);  in build_rcv_fd()
217 	uint32_t keys[8];  in rotate_key()  local
227 		get_keys(fd, keys);  in rotate_key()
228 		memcpy(keys + 4, new_key, KEY_LENGTH);  in rotate_key()
229 		set_keys(fd, keys);  in rotate_key()
231 		/* swap the keys */  in rotate_key()
232 		get_keys(fd, keys);  in rotate_key()
233 		memcpy(tmp_key, keys + 4, KEY_LENGTH);  in rotate_key()
234 		memcpy(keys + 4, keys, KEY_LENGTH);  in rotate_key()
235 		memcpy(keys, tmp_key, KEY_LENGTH);  in rotate_key()
236 		set_keys(fd, keys);  in rotate_key()