/* * xfrd-tcp.h - XFR (transfer) Daemon TCP system header file. Manages tcp conn. * * Copyright (c) 2001-2006, NLnet Labs. All rights reserved. * * See LICENSE for the license. * */ #ifndef XFRD_TCP_H #define XFRD_TCP_H #include "xfrd.h" #ifdef HAVE_TLS_1_3 #include <openssl/ssl.h> #endif struct buffer; struct xfrd_zone; struct xfrd_soa; struct xfrd_state; struct region; struct dname; struct acl_options; struct xfrd_tcp_pipeline; typedef struct xfrd_tcp xfrd_tcp_type; typedef struct xfrd_tcp_set xfrd_tcp_set_type; /* * A set of xfrd tcp connections. */ struct xfrd_tcp_set { /* tcp connections, array, each has packet and read/wr state */ struct xfrd_tcp_pipeline **tcp_state; /* max number of tcp connections, size of tcp_state array */ int tcp_max; /* max number of simultaneous connections on a tcp_pipeline */ int tcp_pipeline; /* number of TCP connections in use. */ int tcp_count; /* TCP timeout. */ int tcp_timeout; /* rbtree with pipelines sorted by master */ rbtree_type* pipetree; #ifdef HAVE_TLS_1_3 /* XoT: SSL context */ SSL_CTX* ssl_ctx; #endif /* double linked list of zones waiting for a TCP connection */ struct xfrd_zone *tcp_waiting_first, *tcp_waiting_last; }; /* * Structure to keep track of an open tcp connection * The xfrd tcp connection is used to first make a request * Then to receive the answer packet(s). */ struct xfrd_tcp { /* tcp connection state */ /* state: reading or writing */ uint8_t is_reading; /* how many bytes have been read/written - total, incl. tcp length bytes */ uint32_t total_bytes; /* msg len bytes */ uint16_t msglen; /* fd of connection. -1 means unconnected */ int fd; /* packet buffer of connection */ struct buffer* packet; }; /* use illegal pointer value to denote skipped ID number. * if this does not work, we can allocate with malloc */ #define TCP_NULL_SKIP ((struct xfrd_zone*)-1) /** * The per-id zone pointers, with TCP_NULL_SKIP or a zone pointer for the * ID value. */ struct xfrd_tcp_pipeline_id { /** rbtree node as first member, this is the key. */ rbnode_type node; /** the ID of this member */ uint16_t id; /** zone pointer or TCP_NULL_SKIP */ struct xfrd_zone* zone; /** next free in free list */ struct xfrd_tcp_pipeline_id* next_free; }; /** * The tcp pipeline key structure. By ip_len, ip, num_unused and unique by * pointer value. */ struct xfrd_tcp_pipeline_key { /* the rbtree node, sorted by IP and nr of unused queries */ rbnode_type node; /* destination IP address */ #ifdef INET6 struct sockaddr_storage ip; #else struct sockaddr_in ip; #endif /* INET6 */ socklen_t ip_len; /* number of unused IDs. used IDs are waiting to send their query, * or have been sent but not not all answer packets have been received. * Sorted by num_unused, so a lookup smaller-equal for 65536 finds the * connection to that master that has the most free IDs. */ int num_unused; /* number of skip-set IDs (these are 'in-use') */ int num_skip; }; /** * Structure to keep track of a pipelined set of queries on * an open tcp connection. The queries may be answered with * interleaved answer packets, the ID number disambiguates. * Sorted by the master IP address so you can use lookup with * smaller-or-equal to find the tcp connection most suitable. */ struct xfrd_tcp_pipeline { /* the key information for the tcp pipeline, in its own * struct so it can be referenced on its own for comparison funcs */ struct xfrd_tcp_pipeline_key key; int handler_added; /* the event handler for this pipe (it'll disambiguate by ID) */ struct event handler; /* the tcp connection to use for reading */ struct xfrd_tcp* tcp_r; /* the tcp connection to use for writing, if it is done successfully, * then the first zone from the sendlist can be removed. */ struct xfrd_tcp* tcp_w; /* once a byte has been written, handshake complete */ int connection_established; #ifdef HAVE_TLS_1_3 /* XoT: SSL object */ SSL *ssl; /* XoT: if SSL handshake is not done, handshake_want indicates the * last error. This may be SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE * when the handshake is still in progress. */ int handshake_want; /* XoT: 1 if the SSL handshake has succeeded, 0 otherwise */ int handshake_done; #endif /* list of queries that want to send, first to get write event, * if NULL, no write event interest */ struct xfrd_zone* tcp_send_first, *tcp_send_last; /* size of the id and unused arrays. */ int pipe_num; /* list of free xfrd_tcp_pipeline_id nodes, these are not in the * zone_per_id tree. preallocated at pipe_num amount. */ struct xfrd_tcp_pipeline_id* pipe_id_free_list; /* The xfrd_zone pointers, per id number. * The key is struct xfrd_tcp_pipeline_id. * per-ID number the queries that have this ID number, every * query owns one ID numbers (until it is done). NULL: unused * When a query is done but not all answer-packets have been * consumed for that ID number, the rest is skipped, this * is denoted with the pointer-value TCP_NULL_SKIP, the ids that * are skipped are not on the unused list. They may be * removed once the last answer packet is skipped. * pipe_num-num_unused values are in the tree (either * a zone pointer or SKIP) */ rbtree_type* zone_per_id; /* Array of uint16_t, with ID values. * unused ID numbers; the first part of the array contains the IDs */ uint16_t* unused; }; /* create set of tcp connections */ struct xfrd_tcp_set* xfrd_tcp_set_create(struct region* region, const char *tls_cert_bundle, int tcp_max, int tcp_pipeline); /* init tcp state */ struct xfrd_tcp* xfrd_tcp_create(struct region* region, size_t bufsize); /* obtain tcp connection for a zone (or wait) */ void xfrd_tcp_obtain(struct xfrd_tcp_set* set, struct xfrd_zone* zone); /* release tcp connection for a zone (starts waiting) */ void xfrd_tcp_release(struct xfrd_tcp_set* set, struct xfrd_zone* zone); /* release tcp pipe entirely (does not stop the zones inside it) */ void xfrd_tcp_pipe_release(struct xfrd_tcp_set* set, struct xfrd_tcp_pipeline* tp, int conn); /* use tcp connection to start xfr */ void xfrd_tcp_setup_write_packet(struct xfrd_tcp_pipeline* tp, struct xfrd_zone* zone); /* initialize tcp_state for a zone. Opens the connection. true on success.*/ int xfrd_tcp_open(struct xfrd_tcp_set* set, struct xfrd_tcp_pipeline* tp, struct xfrd_zone* zone); /* read data from tcp, maybe partial read */ void xfrd_tcp_read(struct xfrd_tcp_pipeline* tp); /* write data to tcp, maybe a partial write */ void xfrd_tcp_write(struct xfrd_tcp_pipeline* tp, struct xfrd_zone* zone); /* handle tcp pipe events */ void xfrd_handle_tcp_pipe(int fd, short event, void* arg); /* * Read from a stream connection (size16)+packet into buffer. * returns value is * -1 on error. * 0 on short read, call back later. * 1 on completed read. * On first call, make sure total_bytes = 0, msglen=0, buffer_clear(). * and the packet and fd need to be set. */ int conn_read(struct xfrd_tcp* conn); /* * Write to a stream connection (size16)+packet. * return value is * -1 on error. 0 on short write, call back later. 1 completed write. * On first call, make sure total_bytes=0, msglen=buffer_limit(), * buffer_flipped(). packet and fd need to be set. */ int conn_write(struct xfrd_tcp* conn); /* setup DNS packet for a query of this type */ void xfrd_setup_packet(struct buffer* packet, uint16_t type, uint16_t klass, const struct dname* dname, uint16_t qid, int* apex_compress); /* write soa in network format to the packet buffer */ void xfrd_write_soa_buffer(struct buffer* packet, const struct dname* apex, struct xfrd_soa* soa, int apex_compress); /* use acl address to setup sockaddr struct, returns length of addr. */ socklen_t xfrd_acl_sockaddr_to(struct acl_options* acl, #ifdef INET6 struct sockaddr_storage *to); #else struct sockaddr_in *to); #endif /* INET6 */ socklen_t xfrd_acl_sockaddr_frm(struct acl_options* acl, #ifdef INET6 struct sockaddr_storage *frm); #else struct sockaddr_in *frm); #endif /* INET6 */ /* create pipeline tcp structure */ struct xfrd_tcp_pipeline* xfrd_tcp_pipeline_create(region_type* region, int tcp_pipeline); /* pick num uint16_t values, from 0..max-1, store in array */ void pick_id_values(uint16_t* array, int num, int max); #ifdef HAVE_SSL void get_cert_info(SSL* ssl, region_type* region, char** cert_serial, char** key_id, char** cert_algorithm, char** tls_version); #endif #endif /* XFRD_TCP_H */
