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Diffstat (limited to 'include/uapi/linux/dns_resolver.h')
| -rw-r--r-- | include/uapi/linux/dns_resolver.h | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/include/uapi/linux/dns_resolver.h b/include/uapi/linux/dns_resolver.h new file mode 100644 index 000000000..129745f9c --- /dev/null +++ b/include/uapi/linux/dns_resolver.h @@ -0,0 +1,116 @@ +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ +/* DNS resolver interface definitions. + * + * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#ifndef _UAPI_LINUX_DNS_RESOLVER_H +#define _UAPI_LINUX_DNS_RESOLVER_H + +#include <linux/types.h> + +/* + * Type of payload. + */ +enum dns_payload_content_type { + DNS_PAYLOAD_IS_SERVER_LIST = 0, /* List of servers, requested by srv=1 */ +}; + +/* + * Type of address that might be found in an address record. + */ +enum dns_payload_address_type { + DNS_ADDRESS_IS_IPV4 = 0, /* 4-byte AF_INET address */ + DNS_ADDRESS_IS_IPV6 = 1, /* 16-byte AF_INET6 address */ +}; + +/* + * Type of protocol used to access a server. + */ +enum dns_payload_protocol_type { + DNS_SERVER_PROTOCOL_UNSPECIFIED = 0, + DNS_SERVER_PROTOCOL_UDP = 1, /* Use UDP to talk to the server */ + DNS_SERVER_PROTOCOL_TCP = 2, /* Use TCP to talk to the server */ +}; + +/* + * Source of record included in DNS resolver payload. + */ +enum dns_record_source { + DNS_RECORD_UNAVAILABLE = 0, /* No source available (empty record) */ + DNS_RECORD_FROM_CONFIG = 1, /* From local configuration data */ + DNS_RECORD_FROM_DNS_A = 2, /* From DNS A or AAAA record */ + DNS_RECORD_FROM_DNS_AFSDB = 3, /* From DNS AFSDB record */ + DNS_RECORD_FROM_DNS_SRV = 4, /* From DNS SRV record */ + DNS_RECORD_FROM_NSS = 5, /* From NSS */ + NR__dns_record_source +}; + +/* + * Status of record included in DNS resolver payload. + */ +enum dns_lookup_status { + DNS_LOOKUP_NOT_DONE = 0, /* No lookup has been made */ + DNS_LOOKUP_GOOD = 1, /* Good records obtained */ + DNS_LOOKUP_GOOD_WITH_BAD = 2, /* Good records, some decoding errors */ + DNS_LOOKUP_BAD = 3, /* Couldn't decode results */ + DNS_LOOKUP_GOT_NOT_FOUND = 4, /* Got a "Not Found" result */ + DNS_LOOKUP_GOT_LOCAL_FAILURE = 5, /* Local failure during lookup */ + DNS_LOOKUP_GOT_TEMP_FAILURE = 6, /* Temporary failure during lookup */ + DNS_LOOKUP_GOT_NS_FAILURE = 7, /* Name server failure */ + NR__dns_lookup_status +}; + +/* + * Header at the beginning of binary format payload. + */ +struct dns_payload_header { + __u8 zero; /* Zero byte: marks this as not being text */ + __u8 content; /* enum dns_payload_content_type */ + __u8 version; /* Encoding version */ +} __packed; + +/* + * Header at the beginning of a V1 server list. This is followed directly by + * the server records. Each server records begins with a struct of type + * dns_server_list_v1_server. + */ +struct dns_server_list_v1_header { + struct dns_payload_header hdr; + __u8 source; /* enum dns_record_source */ + __u8 status; /* enum dns_lookup_status */ + __u8 nr_servers; /* Number of server records following this */ +} __packed; + +/* + * Header at the beginning of each V1 server record. This is followed by the + * characters of the name with no NUL-terminator, followed by the address + * records for that server. Each address record begins with a struct of type + * struct dns_server_list_v1_address. + */ +struct dns_server_list_v1_server { + __u16 name_len; /* Length of name (LE) */ + __u16 priority; /* Priority (as SRV record) (LE) */ + __u16 weight; /* Weight (as SRV record) (LE) */ + __u16 port; /* UDP/TCP port number (LE) */ + __u8 source; /* enum dns_record_source */ + __u8 status; /* enum dns_lookup_status */ + __u8 protocol; /* enum dns_payload_protocol_type */ + __u8 nr_addrs; +} __packed; + +/* + * Header at the beginning of each V1 address record. This is followed by the + * bytes of the address, 4 for IPV4 and 16 for IPV6. + */ +struct dns_server_list_v1_address { + __u8 address_type; /* enum dns_payload_address_type */ +} __packed; + +#endif /* _UAPI_LINUX_DNS_RESOLVER_H */ |