curl/lib/urldata.h

#ifndef __URLDATA_H
#define __URLDATA_H
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id$
 ***************************************************************************/

/* This file is for lib internal stuff */

#include "setup.h"

#define PORT_FTP 21
#define PORT_FTPS 990
#define PORT_TELNET 23
#define PORT_HTTP 80
#define PORT_HTTPS 443
#define PORT_DICT 2628
#define PORT_LDAP 389
#define PORT_TFTP 69

#define DICT_MATCH "/MATCH:"
#define DICT_MATCH2 "/M:"
#define DICT_MATCH3 "/FIND:"
#define DICT_DEFINE "/DEFINE:"
#define DICT_DEFINE2 "/D:"
#define DICT_DEFINE3 "/LOOKUP:"

#define CURL_DEFAULT_USER "anonymous"
#define CURL_DEFAULT_PASSWORD "curl_by_daniel@haxx.se"

#include "cookie.h"
#include "formdata.h"

#ifdef USE_SSLEAY
#ifdef USE_OPENSSL
#include "openssl/rsa.h"
#include "openssl/crypto.h"
#include "openssl/x509.h"
#include "openssl/pem.h"
#include "openssl/ssl.h"
#include "openssl/err.h"
#ifdef HAVE_OPENSSL_ENGINE_H
#include <openssl/engine.h>
#endif
#ifdef HAVE_OPENSSL_PKCS12_H
#include <openssl/pkcs12.h>
#endif
#else /* SSLeay-style includes */
#include "rsa.h"
#include "crypto.h"
#include "x509.h"
#include "pem.h"
#include "ssl.h"
#include "err.h"
#endif /* USE_OPENSSL */
#endif /* USE_SSLEAY */

#ifdef USE_GNUTLS
#include <gnutls/gnutls.h>
#endif

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#include "timeval.h"

#ifdef HAVE_ZLIB_H
#include <zlib.h>               /* for content-encoding */
#endif

#ifdef USE_ARES
#include <ares.h>
#endif

#include <curl/curl.h>

#include "http_chunks.h" /* for the structs and enum stuff */
#include "hostip.h"
#include "hash.h"
#include "splay.h"

#ifdef HAVE_GSSAPI
# ifdef HAVE_GSSGNU
#  include <gss.h>
# elif defined HAVE_GSSMIT
#  include <gssapi/gssapi.h>
#  include <gssapi/gssapi_generic.h>
# else
#  include <gssapi.h>
# endif
#endif

/* Download buffer size, keep it fairly big for speed reasons */
#undef BUFSIZE
#define BUFSIZE CURL_MAX_WRITE_SIZE

/* Initial size of the buffer to store headers in, it'll be enlarged in case
   of need. */
#define HEADERSIZE 256

#define CURLEASY_MAGIC_NUMBER 0xc0dedbad

/* Just a convenience macro to get the larger value out of two given.
   We prefix with CURL to prevent name collisions. */
#define CURLMAX(x,y) ((x)>(y)?(x):(y))

#ifdef HAVE_KRB4
/* Types needed for krb4-ftp connections */
struct krb4buffer {
  void *data;
  size_t size;
  size_t index;
  int eof_flag;
};
enum protection_level {
  prot_clear,
  prot_safe,
  prot_confidential,
  prot_private
};
#endif

/* enum for the nonblocking SSL connection state machine */
typedef enum {
  ssl_connect_1,
  ssl_connect_2,
  ssl_connect_2_reading,
  ssl_connect_2_writing,
  ssl_connect_3,
  ssl_connect_done
} ssl_connect_state;

/* struct for data related to each SSL connection */
struct ssl_connect_data {
  bool use;        /* use ssl encrypted communications TRUE/FALSE */
#ifdef USE_SSLEAY
  /* these ones requires specific SSL-types */
  SSL_CTX* ctx;
  SSL*     handle;
  X509*    server_cert;
  ssl_connect_state connecting_state;
#endif /* USE_SSLEAY */
#ifdef USE_GNUTLS
  gnutls_session session;
  gnutls_certificate_credentials cred;
#endif /* USE_GNUTLS */
};

struct ssl_config_data {
  long version;          /* what version the client wants to use */
  long certverifyresult; /* result from the certificate verification */
  long verifypeer;       /* set TRUE if this is desired */
  long verifyhost;       /* 0: no verify
                            1: check that CN exists
                            2: CN must match hostname */
  char *CApath;          /* DOES NOT WORK ON WINDOWS */
  char *CAfile;          /* cerficate to verify peer against */
  char *random_file;     /* path to file containing "random" data */
  char *egdsocket;       /* path to file containing the EGD daemon socket */
  char *cipher_list;     /* list of ciphers to use */
  long numsessions;      /* SSL session id cache size */
  curl_ssl_ctx_callback fsslctx; /* function to initialize ssl ctx */
  void *fsslctxp;        /* parameter for call back */
  bool sessionid;        /* cache session IDs or not */
};

/* information stored about one single SSL session */
struct curl_ssl_session {
  char *name;       /* host name for which this ID was used */
  void *sessionid;  /* as returned from the SSL layer */
  size_t idsize;    /* if known, otherwise 0 */
  long age;         /* just a number, the higher the more recent */
  unsigned short remote_port; /* remote port to connect to */
  struct ssl_config_data ssl_config; /* setup for this session */
};

/* Struct used for Digest challenge-response authentication */
struct digestdata {
  char *nonce;
  char *cnonce;
  char *realm;
  int algo;
  bool stale; /* set true for re-negotiation */
  char *opaque;
  char *qop;
  char *algorithm;
  int nc; /* nounce count */
};

typedef enum {
  NTLMSTATE_NONE,
  NTLMSTATE_TYPE1,
  NTLMSTATE_TYPE2,
  NTLMSTATE_TYPE3,
  NTLMSTATE_LAST
} curlntlm;

#ifdef USE_WINDOWS_SSPI
/* When including these headers, you must define either SECURITY_WIN32
 * or SECURITY_KERNEL, indicating who is compiling the code.
 */
#define SECURITY_WIN32 1
#include <security.h>
#include <sspi.h>
#include <rpc.h>
#endif

#if defined(CURL_DOES_CONVERSIONS) && defined(HAVE_ICONV)
#include <iconv.h>
#endif

/* Struct used for NTLM challenge-response authentication */
struct ntlmdata {
  curlntlm state;
#ifdef USE_WINDOWS_SSPI
  CredHandle handle;
  CtxtHandle c_handle;
  SEC_WINNT_AUTH_IDENTITY identity;
  SEC_WINNT_AUTH_IDENTITY *p_identity;
  int has_handles;
  void *type_2;
  int n_type_2;
#else
  unsigned int flags;
  unsigned char nonce[8];
#endif
};

#ifdef HAVE_GSSAPI
struct negotiatedata {
  bool gss; /* Whether we're processing GSS-Negotiate or Negotiate */
  const char* protocol; /* "GSS-Negotiate" or "Negotiate" */
  OM_uint32 status;
  gss_ctx_id_t context;
  gss_name_t server_name;
  gss_buffer_desc output_token;
};
#endif

/****************************************************************************
 * HTTP unique setup
 ***************************************************************************/
struct HTTP {
  struct FormData *sendit;
  curl_off_t postsize; /* off_t to handle large file sizes */
  char *postdata;

  const char *p_pragma;      /* Pragma: string */
  const char *p_accept;      /* Accept: string */
  curl_off_t readbytecount;
  curl_off_t writebytecount;

  /* For FORM posting */
  struct Form form;
  struct Curl_chunker chunk;

  struct back {
    curl_read_callback fread; /* backup storage for fread pointer */
    void *fread_in;           /* backup storage for fread_in pointer */
    char *postdata;
    curl_off_t postsize;
  } backup;

  enum {
    HTTPSEND_NADA,    /* init */
    HTTPSEND_REQUEST, /* sending a request */
    HTTPSEND_BODY,    /* sending body */
    HTTPSEND_LAST     /* never use this */
  } sending;

  void *send_buffer; /* used if the request couldn't be sent in one chunk,
                        points to an allocated send_buffer struct */
};

/****************************************************************************
 * FTP unique setup
 ***************************************************************************/
typedef enum {
  FTP_STOP,    /* do nothing state, stops the state machine */
  FTP_WAIT220, /* waiting for the inintial 220 response immediately after
                  a connect */
  FTP_AUTH,
  FTP_USER,
  FTP_PASS,
  FTP_ACCT,
  FTP_PBSZ,
  FTP_PROT,
  FTP_PWD,
  FTP_QUOTE, /* waiting for a response to a command sent in a quote list */
  FTP_RETR_PREQUOTE,
  FTP_STOR_PREQUOTE,
  FTP_POSTQUOTE,
  FTP_CWD,  /* change dir */
  FTP_MKD,  /* if the dir didn't exist */
  FTP_MDTM, /* to figure out the datestamp */
  FTP_TYPE, /* to set type when doing a head-like request */
  FTP_LIST_TYPE, /* set type when about to do a dir list */
  FTP_RETR_TYPE, /* set type when about to RETR a file */
  FTP_STOR_TYPE, /* set type when about to STOR a file */
  FTP_SIZE, /* get the remote file's size for head-like request */
  FTP_RETR_SIZE, /* get the remote file's size for RETR */
  FTP_STOR_SIZE, /* get the size for (resumed) STOR */
  FTP_REST, /* when used to check if the server supports it in head-like */
  FTP_RETR_REST, /* when asking for "resume" in for RETR */
  FTP_PORT, /* generic state for PORT, LPRT and EPRT, check count1 */
  FTP_PASV, /* generic state for PASV and EPSV, check count1 */
  FTP_LIST, /* generic state for LIST, NLST or a custom list command */
  FTP_RETR,
  FTP_STOR, /* generic state for STOR and APPE */
  FTP_QUIT,
  FTP_LAST  /* never used */
} ftpstate;

typedef enum {
  FTPFILE_MULTICWD  = 1, /* as defined by RFC1738 */
  FTPFILE_NOCWD     = 2, /* use SIZE / RETR / STOR on the full path */
  FTPFILE_SINGLECWD = 3  /* make one CWD, then SIZE / RETR / STOR on the file */
} curl_ftpfile;

/* This FTP struct is used in the SessionHandle. All FTP data that is
   connection-oriented must be in FTP_conn to properly deal with the fact that
   perhaps the SessionHandle is changed between the times the connection is
   used. */
struct FTP {
  curl_off_t *bytecountp;
  char *user;    /* user name string */
  char *passwd;  /* password string */
  char *urlpath; /* the originally given path part of the URL */
  char *file;    /* decoded file */
  bool no_transfer; /* nothing was transfered, (possibly because a resumed
                       transfer already was complete) */
  curl_off_t downloadsize;
};

/* ftp_conn is used for striuct connection-oriented data in the connectdata
   struct */
struct ftp_conn {
  char *entrypath; /* the PWD reply when we logged on */
  char **dirs;   /* realloc()ed array for path components */
  int dirdepth;  /* number of entries used in the 'dirs' array */
  int diralloc;  /* number of entries allocated for the 'dirs' array */
  char *cache;       /* data cache between getresponse()-calls */
  curl_off_t cache_size; /* size of cache in bytes */
  bool dont_check;  /* Set to TRUE to prevent the final (post-transfer)
                       file size and 226/250 status check. It should still
                       read the line, just ignore the result. */
  long response_time; /* When no timeout is given, this is the amount of
                         seconds we await for an FTP response. Initialized
                         in Curl_ftp_connect() */
  bool ctl_valid;   /* Tells Curl_ftp_quit() whether or not to do anything. If
                       the connection has timed out or been closed, this
                       should be FALSE when it gets to Curl_ftp_quit() */
  bool cwddone;     /* if it has been determined that the proper CWD combo
                       already has been done */
  bool cwdfail;     /* set TRUE if a CWD command fails, as then we must prevent
                       caching the current directory */
  char *prevpath;   /* conn->path from the previous transfer */
  char transfertype; /* set by ftp_transfertype for use by Curl_client_write()a
                        and others (A/I or zero) */
  size_t nread_resp; /* number of bytes currently read of a server response */
  char *linestart_resp; /* line start pointer for the FTP server response
                           reader function */

  int count1; /* general purpose counter for the state machine */
  int count2; /* general purpose counter for the state machine */
  int count3; /* general purpose counter for the state machine */
  char *sendthis; /* allocated pointer to a buffer that is to be sent to the
                     ftp server */
  size_t sendleft; /* number of bytes left to send from the sendthis buffer */
  size_t sendsize; /* total size of the sendthis buffer */
  struct timeval response; /* set to Curl_tvnow() when a command has been sent
                              off, used to time-out response reading */
  ftpstate state; /* always use ftp.c:state() to change state! */
};

/****************************************************************************
 * FILE unique setup
 ***************************************************************************/
struct FILEPROTO {
  char *path; /* the path we operate on */
  char *freepath; /* pointer to the allocated block we must free, this might
                     differ from the 'path' pointer */
  int fd;     /* open file descriptor to read from! */
};

/*
 * Boolean values that concerns this connection.
 */
struct ConnectBits {
  bool close; /* if set, we close the connection after this request */
  bool reuse; /* if set, this is a re-used connection */
  bool chunk; /* if set, this is a chunked transfer-encoding */
  bool httpproxy;    /* if set, this transfer is done through a http proxy */
  bool user_passwd;    /* do we use user+password for this connection? */
  bool proxy_user_passwd; /* user+password for the proxy? */
  bool ipv6_ip; /* we communicate with a remote site specified with pure IPv6
                   IP address */
  bool ipv6;    /* we communicate with a site using an IPv6 address */

  bool do_more; /* this is set TRUE if the ->curl_do_more() function is
                   supposed to be called, after ->curl_do() */

  bool upload_chunky; /* set TRUE if we are doing chunked transfer-encoding
                         on upload */
  bool getheader;     /* TRUE if header parsing is wanted */

  bool forbidchunk;   /* used only to explicitly forbid chunk-upload for
                         specific upload buffers. See readmoredata() in
                         http.c for details. */

  bool tcpconnect;    /* the TCP layer (or simimlar) is connected, this is set
                         the first time on the first connect function call */
  bool protoconnstart;/* the protocol layer has STARTED its operation after
                         the TCP layer connect */

  bool retry;         /* this connection is about to get closed and then
                         re-attempted at another connection. */
  bool no_body;       /* CURLOPT_NO_BODY (or similar) was set */
  bool tunnel_proxy;  /* if CONNECT is used to "tunnel" through the proxy.
                         This is implicit when SSL-protocols are used through
                         proxies, but can also be enabled explicitly by
                         apps */
  bool authneg;       /* TRUE when the auth phase has started, which means
                         that we are creating a request with an auth header,
                         but it is not the final request in the auth
                         negotiation. */
  bool rewindaftersend;/* TRUE when the sending couldn't be stopped even
                          though it will be discarded. When the whole send
                          operation is done, we must call the data rewind
                          callback. */
  bool ftp_use_epsv;  /* As set with CURLOPT_FTP_USE_EPSV, but if we find out
                         EPSV doesn't work we disable it for the forthcoming
                         requests */

  bool ftp_use_eprt;  /* As set with CURLOPT_FTP_USE_EPRT, but if we find out
                         EPRT doesn't work we disable it for the forthcoming
                         requests */
  bool netrc;         /* name+password provided by netrc */

  bool trailerHdrPresent; /* Set when Trailer: header found in HTTP response.
                             Required to determine whether to look for trailers
                             in case of Transfer-Encoding: chunking */
  bool done;          /* set to FALSE when Curl_do() is called and set to TRUE
                         when Curl_done() is called, to prevent Curl_done() to
                         get invoked twice when the multi interface is
                         used. */
  bool stream_was_rewound; /* Indicates that the stream was rewound after a request
                              read past the end of its response byte boundary */
};

struct hostname {
  char *rawalloc; /* allocated "raw" version of the name */
  char *encalloc; /* allocated IDN-encoded version of the name */
  char *name;     /* name to use internally, might be encoded, might be raw */
  char *dispname; /* name to display, as 'name' might be encoded */
};

/*
 * Flags on the keepon member of the Curl_transfer_keeper
 */
enum {
  KEEP_NONE,
  KEEP_READ,
  KEEP_WRITE
};


/*
 * This struct is all the previously local variables from Curl_perform() moved
 * to struct to allow the function to return and get re-invoked better without
 * losing state.
 */

struct Curl_transfer_keeper {

  /** Values copied over from the HandleData struct each time on init **/

  curl_off_t size;        /* -1 if unknown at this point */
  curl_off_t *bytecountp; /* return number of bytes read or NULL */

  curl_off_t maxdownload; /* in bytes, the maximum amount of data to fetch, 0
                             means unlimited */
  curl_off_t *writebytecountp; /* return number of bytes written or NULL */

  /** End of HandleData struct copies **/

  curl_off_t bytecount;         /* total number of bytes read */
  curl_off_t writebytecount;    /* number of bytes written */

  long headerbytecount;  /* only count received headers */
  long deductheadercount; /* this amount of bytes doesn't count when we check
                             if anything has been transfered at the end of
                             a connection. We use this counter to make only
                             a 100 reply (without a following second response
                             code) result in a CURLE_GOT_NOTHING error code */

  struct timeval start;         /* transfer started at this time */
  struct timeval now;           /* current time */
  bool header;                  /* incoming data has HTTP header */
  enum {
    HEADER_NORMAL,              /* no bad header at all */
    HEADER_PARTHEADER,          /* part of the chunk is a bad header, the rest
                                   is normal data */
    HEADER_ALLBAD               /* all was believed to be header */
  } badheader;                  /* the header was deemed bad and will be
                                   written as body */
  int headerline;               /* counts header lines to better track the
                                   first one */
  char *hbufp;                  /* points at *end* of header line */
  size_t hbuflen;
  char *str;                    /* within buf */
  char *str_start;              /* within buf */
  char *end_ptr;                /* within buf */
  char *p;                      /* within headerbuff */
  bool content_range;           /* set TRUE if Content-Range: was found */
  curl_off_t offset;            /* possible resume offset read from the
                                   Content-Range: header */
  int httpcode;                 /* error code from the 'HTTP/1.? XXX' line */
  int httpversion;              /* the HTTP version*10 */
  struct timeval start100;      /* time stamp to wait for the 100 code from */
  bool write_after_100_header;  /* TRUE = we enable the write after we
                                   received a 100-continue/timeout or
                                   FALSE = directly */
  bool wait100_after_headers;   /* TRUE = after the request-headers have been
                                   sent off properly, we go into the wait100
                                   state, FALSE = don't */
  int content_encoding;         /* What content encoding. sec 3.5, RFC2616. */

#define IDENTITY 0              /* No encoding */
#define DEFLATE 1               /* zlib delfate [RFC 1950 & 1951] */
#define GZIP 2                  /* gzip algorithm [RFC 1952] */
#define COMPRESS 3              /* Not handled, added for completeness */

#ifdef HAVE_LIBZ
  bool zlib_init;               /* True if zlib already initialized;
                                   undefined if Content-Encoding header. */
  z_stream z;                   /* State structure for zlib. */
#endif

  time_t timeofdoc;
  long bodywrites;

  char *buf;
  char *uploadbuf;
  curl_socket_t maxfd;

  int keepon;

  bool upload_done; /* set to TRUE when doing chunked transfer-encoding upload
                       and we're uploading the last chunk */

  bool ignorebody;  /* we read a response-body but we ignore it! */
  bool ignorecl;    /* This HTTP response has no body so we ignore the Content-
                       Length: header */
};

#if defined(USE_ARES) || defined(USE_THREADING_GETHOSTBYNAME) || \
    defined(USE_THREADING_GETADDRINFO)
struct Curl_async {
  char *hostname;
  int port;
  struct Curl_dns_entry *dns;
  bool done;  /* set TRUE when the lookup is complete */
  int status; /* if done is TRUE, this is the status from the callback */
  void *os_specific;  /* 'struct thread_data' for Windows */
};
#endif

#define FIRSTSOCKET     0
#define SECONDARYSOCKET 1

/* These function pointer types are here only to allow easier typecasting
   within the source when we need to cast between data pointers (such as NULL)
   and function pointers. */
typedef CURLcode (*Curl_do_more_func)(struct connectdata *);
typedef CURLcode (*Curl_done_func)(struct connectdata *, CURLcode);


/*
 * Store's request specific data in the easy handle (SessionHandle).
 * Previously, these members were on the connectdata struct but since
 * a conn struct may now be shared between different SessionHandles,
 * we store connection-specifc data here.
 *
 */
struct HandleData {
  char *pathbuffer;/* allocated buffer to store the URL's path part in */
  char *path;      /* path to use, points to somewhere within the pathbuffer
                      area */

  char *newurl; /* This can only be set if a Location: was in the
                   document headers */

  /* This struct is inited when needed */
  struct Curl_transfer_keeper keep;

  /* 'upload_present' is used to keep a byte counter of how much data there is
     still left in the buffer, aimed for upload. */
  ssize_t upload_present;

   /* 'upload_fromhere' is used as a read-pointer when we uploaded parts of a
      buffer, so the next read should read from where this pointer points to,
      and the 'upload_present' contains the number of bytes available at this
      position */
  char *upload_fromhere;

  curl_off_t size;        /* -1 if unknown at this point */
  curl_off_t *bytecountp; /* return number of bytes read or NULL */

  curl_off_t maxdownload; /* in bytes, the maximum amount of data to fetch, 0
                             means unlimited */
  curl_off_t *writebytecountp; /* return number of bytes written or NULL */

  bool use_range;
  bool rangestringalloc; /* the range string is malloc()'ed */

  char *range; /* range, if used. See README for detailed specification on
                  this syntax. */
  curl_off_t resume_from; /* continue [ftp] transfer from here */

  /* Protocol specific data */

  union {
    struct HTTP *http;
    struct HTTP *https;  /* alias, just for the sake of being more readable */
    struct FTP *ftp;
    void *tftp;        /* private for tftp.c-eyes only */
    struct FILEPROTO *file;
    void *telnet;        /* private for telnet.c-eyes only */
    void *generic;
  } proto;
};

/*
 * The connectdata struct contains all fields and variables that should be
 * unique for an entire connection.
 */
struct connectdata {
  /* 'data' is the CURRENT SessionHandle using this connection -- take great
     caution that this might very well vary between different times this
     connection is used! */
  struct SessionHandle *data;

  bool inuse; /* This is a marker for the connection cache logic. If this is
                 TRUE this handle is being used by an easy handle and cannot
                 be used by any other easy handle without careful
                 consideration (== only for pipelining). */

  /**** Fields set when inited and not modified again */
  long connectindex; /* what index in the connection cache connects index this
                        particular struct has */
  long protocol; /* PROT_* flags concerning the protocol set */
#define PROT_MISSING (1<<0)
#define PROT_CLOSEACTION (1<<1) /* needs action before socket close */
#define PROT_HTTP    (1<<2)
#define PROT_HTTPS   (1<<3)
#define PROT_FTP     (1<<4)
#define PROT_TELNET  (1<<5)
#define PROT_DICT    (1<<6)
#define PROT_LDAP    (1<<7)
#define PROT_FILE    (1<<8)
#define PROT_FTPS    (1<<9)
#define PROT_SSL     (1<<10) /* protocol requires SSL */
#define PROT_TFTP    (1<<11)

  /* 'dns_entry' is the particular host we use. This points to an entry in the
     DNS cache and it will not get pruned while locked. It gets unlocked in
     Curl_done(). This entry will be NULL if the connection is re-used as then
     there is no name resolve done. */
  struct Curl_dns_entry *dns_entry;

  /* 'ip_addr' is the particular IP we connected to. It points to a struct
     within the DNS cache, so this pointer is only valid as long as the DNS
     cache entry remains locked. It gets unlocked in Curl_done() */
  Curl_addrinfo *ip_addr;

  /* 'ip_addr_str' is the ip_addr data as a human readable malloc()ed string.
     It remains available as long as the connection does, which is longer than
     the ip_addr itself. Set with Curl_store_ip_addr() when ip_addr has been
     set. */
  char *ip_addr_str;

  char protostr[16];  /* store the protocol string in this buffer */
  int socktype;  /* SOCK_STREAM or SOCK_DGRAM */

  struct hostname host;
  struct hostname proxy;

  long port;       /* which port to use locally */
  unsigned short remote_port; /* what remote port to connect to,
                                 not the proxy port! */

  char *user;    /* user name string, allocated */
  char *passwd;  /* password string, allocated */

  char *proxyuser;    /* proxy user name string, allocated */
  char *proxypasswd;  /* proxy password string, allocated */

  struct timeval now;     /* "current" time */
  struct timeval created; /* creation time */
  curl_socket_t sock[2]; /* two sockets, the second is used for the data
                            transfer when doing FTP */

  struct ssl_connect_data ssl[2]; /* this is for ssl-stuff */
  struct ssl_config_data ssl_config;

  struct ConnectBits bits;    /* various state-flags for this connection */

  /* These two functions MUST be set by the curl_connect() function to be
     be protocol dependent */
  CURLcode (*curl_do)(struct connectdata *, bool *done);
  Curl_done_func curl_done;

  /* If the curl_do() function is better made in two halves, this
   * curl_do_more() function will be called afterwards, if set. For example
   * for doing the FTP stuff after the PASV/PORT command.
   */
  Curl_do_more_func curl_do_more;

  /* This function *MAY* be set to a protocol-dependent function that is run
   * after the connect() and everything is done, as a step in the connection.
   * The 'done' pointer points to a bool that should be set to TRUE if the
   * function completes before return. If it doesn't complete, the caller
   * should call the curl_connecting() function until it is.
   */
  CURLcode (*curl_connect)(struct connectdata *, bool *done);

  /* See above. Currently only used for FTP. */
  CURLcode (*curl_connecting)(struct connectdata *, bool *done);
  CURLcode (*curl_doing)(struct connectdata *, bool *done);

  /* Called from the multi interface during the PROTOCONNECT phase, and it
     should then return a proper fd set */
  int (*curl_proto_getsock)(struct connectdata *conn,
                            curl_socket_t *socks,
                            int numsocks);

  /* Called from the multi interface during the DOING phase, and it should
     then return a proper fd set */
  int (*curl_doing_getsock)(struct connectdata *conn,
                            curl_socket_t *socks,
                            int numsocks);

  /* This function *MAY* be set to a protocol-dependent function that is run
   * by the curl_disconnect(), as a step in the disconnection.
   */
  CURLcode (*curl_disconnect)(struct connectdata *);

  /* This function *MAY* be set to a protocol-dependent function that is run
   * in the curl_close() function if protocol-specific cleanups are required.
   */
  CURLcode (*curl_close)(struct connectdata *);

  /**** curl_get() phase fields */

  curl_socket_t sockfd;   /* socket to read from or CURL_SOCKET_BAD */
  curl_socket_t writesockfd; /* socket to write to, it may very
                                well be the same we read from.
                                CURL_SOCKET_BAD disables */

  /** Dynamicly allocated strings, may need to be freed before this **/
  /** struct is killed.                                             **/
  struct dynamically_allocated_data {
    char *proxyuserpwd; /* free later if not NULL! */
    char *uagent; /* free later if not NULL! */
    char *accept_encoding; /* free later if not NULL! */
    char *userpwd; /* free later if not NULL! */
    char *rangeline; /* free later if not NULL! */
    char *ref; /* free later if not NULL! */
    char *host; /* free later if not NULL */
    char *cookiehost; /* free later if not NULL */
  } allocptr;

  int sec_complete; /* if krb4 is enabled for this connection */
#ifdef HAVE_KRB4
  enum protection_level command_prot;
  enum protection_level data_prot;
  enum protection_level request_data_prot;
  size_t buffer_size;
  struct krb4buffer in_buffer, out_buffer;
  void *app_data;
  const struct Curl_sec_client_mech *mech;
  struct sockaddr_in local_addr;
#endif

  bool readchannel_inuse;  /* whether the read channel is in use by an easy handle */
  bool writechannel_inuse; /* whether the write channel is in use by an easy handle */
  bool is_in_pipeline;     /* TRUE if this connection is in a pipeline */

  struct curl_llist *send_pipe; /* List of handles waiting to
                                   send on this pipeline */
  struct curl_llist *recv_pipe; /* List of handles waiting to read
                                   their responses on this pipeline */

  char master_buffer[BUFSIZE]; /* The master buffer for this connection. */
  size_t read_pos;
  size_t buf_len;


  /*************** Request - specific items ************/

  /* previously this was in the urldata struct */
  curl_read_callback fread; /* function that reads the input */
  void *fread_in;           /* pointer to pass to the fread() above */

  struct ntlmdata ntlm;     /* NTLM differs from other authentication schemes
                               because it authenticates connections, not
                               single requests! */
  struct ntlmdata proxyntlm; /* NTLM data for proxy */

  char syserr_buf [256]; /* buffer for Curl_strerror() */

#if defined(USE_ARES) || defined(USE_THREADING_GETHOSTBYNAME) || \
    defined(USE_THREADING_GETADDRINFO)
  /* data used for the asynch name resolve callback */
  struct Curl_async async;
#endif

  /* These three are used for chunked-encoding trailer support */
  char *trailer; /* allocated buffer to store trailer in */
  int trlMax;    /* allocated buffer size */
  int trlPos;    /* index of where to store data */

  union {
    struct ftp_conn ftpc;
  } proto;
};

/* The end of connectdata. */

/*
 * Struct to keep statistical and informational data.
 */
struct PureInfo {
  int httpcode;  /* Recent HTTP or FTP response code */
  int httpproxycode;
  int httpversion;
  long filetime; /* If requested, this is might get set. Set to -1 if the time
                    was unretrievable. We cannot have this of type time_t,
                    since time_t is unsigned on several platforms such as
                    OpenVMS. */
  long header_size;  /* size of read header(s) in bytes */
  long request_size; /* the amount of bytes sent in the request(s) */

  long proxyauthavail;
  long httpauthavail;

  long numconnects; /* how many new connection did libcurl created */

  char *contenttype; /* the content type of the object */
};


struct Progress {
  long lastshow; /* time() of the last displayed progress meter or NULL to
                    force redraw at next call */
  curl_off_t size_dl; /* total expected size */
  curl_off_t size_ul; /* total expected size */
  curl_off_t downloaded; /* transfered so far */
  curl_off_t uploaded; /* transfered so far */

  curl_off_t current_speed; /* uses the currently fastest transfer */

  bool callback;  /* set when progress callback is used */
  int width; /* screen width at download start */
  int flags; /* see progress.h */

  double timespent;

  curl_off_t dlspeed;
  curl_off_t ulspeed;

  double t_nslookup;
  double t_connect;
  double t_pretransfer;
  double t_starttransfer;
  double t_redirect;

  struct timeval start;
  struct timeval t_startsingle;
#define CURR_TIME (5+1) /* 6 entries for 5 seconds */

  curl_off_t speeder[ CURR_TIME ];
  struct timeval speeder_time[ CURR_TIME ];
  int speeder_c;
};

typedef enum {
  HTTPREQ_NONE, /* first in list */
  HTTPREQ_GET,
  HTTPREQ_POST,
  HTTPREQ_POST_FORM, /* we make a difference internally */
  HTTPREQ_PUT,
  HTTPREQ_HEAD,
  HTTPREQ_CUSTOM,
  HTTPREQ_LAST /* last in list */
} Curl_HttpReq;

/*
 * Values that are generated, temporary or calculated internally for a
 * "session handle" must be defined within the 'struct UrlState'.  This struct
 * will be used within the SessionHandle struct. When the 'SessionHandle'
 * struct is cloned, this data MUST NOT be copied.
 *
 * Remember that any "state" information goes globally for the curl handle.
 * Session-data MUST be put in the connectdata struct and here.  */
#define MAX_CURL_USER_LENGTH 256
#define MAX_CURL_PASSWORD_LENGTH 256
#define MAX_CURL_USER_LENGTH_TXT "255"
#define MAX_CURL_PASSWORD_LENGTH_TXT "255"

struct auth {
  long want;  /* Bitmask set to the authentication methods wanted by the app
                 (with CURLOPT_HTTPAUTH or CURLOPT_PROXYAUTH). */
  long picked;
  long avail; /* bitmask for what the server reports to support for this
                 resource */
  bool done;  /* TRUE when the auth phase is done and ready to do the *actual*
                 request */
  bool multi; /* TRUE if this is not yet authenticated but within the auth
                 multipass negotiation */

};

struct conncache {
  /* 'connects' will be an allocated array with pointers. If the pointer is
     set, it holds an allocated connection. */
  struct connectdata **connects;
  long num;           /* number of entries of the 'connects' array */
  enum {
    CONNCACHE_PRIVATE, /* used for an easy handle alone */
    CONNCACHE_MULTI    /* shared within a multi handle */
  } type;
};


struct UrlState {
  enum {
    Curl_if_none,
    Curl_if_easy,
    Curl_if_multi
  } used_interface;

  struct conncache *connc; /* points to the connection cache this handle
                              uses */

  /* buffers to store authentication data in, as parsed from input options */
  struct timeval keeps_speed; /* for the progress meter really */

  long lastconnect;  /* index of most recent connect or -1 if undefined */

  char *headerbuff; /* allocated buffer to store headers in */
  size_t headersize;   /* size of the allocation */

  char buffer[BUFSIZE+1]; /* download buffer */
  char uploadbuffer[BUFSIZE+1]; /* upload buffer */
  curl_off_t current_speed;  /* the ProgressShow() funcion sets this,
                                bytes / second */
  bool this_is_a_follow; /* this is a followed Location: request */

  bool is_in_pipeline; /* Indicates whether this handle is part of a pipeline */

  char *first_host; /* if set, this should be the host name that we will
                       sent authorization to, no else. Used to make Location:
                       following not keep sending user+password... This is
                       strdup() data.
                    */

  struct curl_ssl_session *session; /* array of 'numsessions' size */
  long sessionage;                  /* number of the most recent session */

  char *scratch; /* huge buffer[BUFSIZE*2] when doing upload CRLF replacing */
  bool errorbuf; /* Set to TRUE if the error buffer is already filled in.
                    This must be set to FALSE every time _easy_perform() is
                    called. */
  int os_errno;  /* filled in with errno whenever an error occurs */
#ifdef HAVE_SIGNAL
  /* storage for the previous bag^H^H^HSIGPIPE signal handler :-) */
  void (*prev_signal)(int sig);
#endif
  bool allow_port; /* Is set.use_port allowed to take effect or not. This
                      is always set TRUE when curl_easy_perform() is called. */

  struct digestdata digest;
  struct digestdata proxydigest;

#ifdef HAVE_GSSAPI
  struct negotiatedata negotiate;
#endif

  struct auth authhost;
  struct auth authproxy;

  bool authproblem; /* TRUE if there's some problem authenticating */

#ifdef USE_ARES
  ares_channel areschannel; /* for name resolves */
#endif

#if defined(USE_SSLEAY) && defined(HAVE_OPENSSL_ENGINE_H)
  ENGINE *engine;
#endif /* USE_SSLEAY */
  struct timeval expiretime; /* set this with Curl_expire() only */
  struct Curl_tree timenode; /* for the splay stuff */

  /* a place to store the most recenlty set FTP entrypath */
  char *most_recent_ftp_entrypath;

  /* set after initial USER failure, to prevent an authentication loop */
  bool ftp_trying_alternative;

  bool expect100header;  /* TRUE if we added Expect: 100-continue */

  bool pipe_broke; /* TRUE if the connection we were pipelined on broke
                      and we need to restart from the beginning */
  bool cancelled; /* TRUE if the request was cancelled */

#ifndef WIN32
/* do FTP line-end conversions on most platforms */
#define CURL_DO_LINEEND_CONV
  /* for FTP downloads: track CRLF sequences that span blocks */
  bool prev_block_had_trailing_cr;
  /* for FTP downloads: how many CRLFs did we converted to LFs? */
  curl_off_t crlf_conversions;
#endif
  /* If set to non-NULL, there's a connection in a shared connection cache
     that uses this handle so we can't kill this SessionHandle just yet but
     must keep it around and add it to the list of handles to kill once all
     its connections are gone */
  void *shared_conn;
  bool closed; /* set to TRUE when curl_easy_cleanup() has been called on this
                  handle, but it is kept around as mentioned for
                  shared_conn */
};


/*
 * This 'DynamicStatic' struct defines dynamic states that actually change
 * values in the 'UserDefined' area, which MUST be taken into consideration
 * if the UserDefined struct is cloned or similar. You can probably just
 * copy these, but each one indicate a special action on other data.
 */

struct DynamicStatic {
  char *url;        /* work URL, copied from UserDefined */
  bool url_alloc;   /* URL string is malloc()'ed */
  bool url_changed; /* set on CURL_OPT_URL, used to detect if the URL was
                       changed after the connect phase, as we allow callback
                       to change it and if so, we reconnect to use the new
                       URL instead */
  char *proxy;      /* work proxy, copied from UserDefined */
  bool proxy_alloc; /* http proxy string is malloc()'ed */
  char *referer;    /* referer string */
  bool referer_alloc; /* referer sting is malloc()ed */
  struct curl_slist *cookielist; /* list of cookie files set by
                                    curl_easy_setopt(COOKIEFILE) calls */
};

/*
 * This 'UserDefined' struct must only contain data that is set once to go
 * for many (perhaps) independent connections. Values that are generated or
 * calculated internally for the "session handle" MUST be defined within the
 * 'struct UrlState' instead. The only exceptions MUST note the changes in
 * the 'DynamicStatic' struct.
 */
struct Curl_one_easy; /* declared and used only in multi.c */
struct Curl_multi;    /* declared and used only in multi.c */

struct UserDefined {
  FILE *err;         /* the stderr user data goes here */
  void *debugdata;   /* the data that will be passed to fdebug */
  char *errorbuffer; /* store failure messages in here */
  char *proxyuserpwd;  /* Proxy <user:password>, if used */
  long proxyport; /* If non-zero, use this port number by default. If the
                     proxy string features a ":[port]" that one will override
                     this. */
  void *out;         /* the fetched file goes here */
  void *in;          /* the uploaded file is read from here */
  void *writeheader; /* write the header to this if non-NULL */
  char *set_url;     /* what original URL to work on */
  char *set_proxy;   /* proxy to use */
  long use_port;     /* which port to use (when not using default) */
  char *userpwd;     /* <user:password>, if used */
  long httpauth;     /* what kind of HTTP authentication to use (bitmask) */
  long proxyauth;    /* what kind of proxy authentication to use (bitmask) */
  char *set_range;   /* range, if used. See README for detailed specification
                        on this syntax. */
  long followlocation; /* as in HTTP Location: */
  long maxredirs;    /* maximum no. of http(s) redirects to follow, set to -1
                        for infinity */
  char *set_referer; /* custom string */
  bool free_referer; /* set TRUE if 'referer' points to a string we
                        allocated */
  char *useragent;   /* User-Agent string */
  char *encoding;    /* Accept-Encoding string */
  char *postfields;  /* if POST, set the fields' values here */
  curl_off_t postfieldsize; /* if POST, this might have a size to use instead
                               of strlen(), and then the data *may* be binary
                               (contain zero bytes) */
  char *ftpport;     /* port to send with the FTP PORT command */
  char *device;      /* local network interface/address to use */
  unsigned short localport; /* local port number to bind to */
  int localportrange; /* number of additional port numbers to test in case the
                         'localport' one can't be bind()ed */
  curl_write_callback fwrite;        /* function that stores the output */
  curl_write_callback fwrite_header; /* function that stores headers */
  curl_read_callback fread;          /* function that reads the input */
  curl_progress_callback fprogress;  /* function for progress information */
  curl_debug_callback fdebug;      /* function that write informational data */
  curl_ioctl_callback ioctl;       /* function for I/O control */
  curl_sockopt_callback fsockopt;  /* function for setting socket options */
  void *sockopt_client; /* pointer to pass to the socket options callback */

  /* the 3 curl_conv_callback functions below are used on non-ASCII hosts */
  /* function to convert from the network encoding: */
  curl_conv_callback convfromnetwork;
  /* function to convert to the network encoding: */
  curl_conv_callback convtonetwork;
  /* function to convert from UTF-8 encoding: */
  curl_conv_callback convfromutf8;

  void *progress_client; /* pointer to pass to the progress callback */
  void *ioctl_client;   /* pointer to pass to the ioctl callback */
  long timeout;         /* in seconds, 0 means no timeout */
  long connecttimeout;  /* in seconds, 0 means no timeout */
  long ftp_response_timeout; /* in seconds, 0 means no timeout */
  curl_off_t infilesize;      /* size of file to upload, -1 means unknown */
  long low_speed_limit; /* bytes/second */
  long low_speed_time;  /* number of seconds */
  curl_off_t max_send_speed; /* high speed limit in bytes/second for upload */
  curl_off_t max_recv_speed; /* high speed limit in bytes/second for download */
  curl_off_t set_resume_from;  /* continue [ftp] transfer from here */
  char *cookie;         /* HTTP cookie string to send */
  struct curl_slist *headers; /* linked list of extra headers */
  struct curl_httppost *httppost;  /* linked list of POST data */
  char *cert;           /* certificate */
  char *cert_type;      /* format for certificate (default: PEM) */
  char *key;            /* private key */
  char *key_type;       /* format for private key (default: PEM) */
  char *key_passwd;     /* plain text private key password */
  char *cookiejar;      /* dump all cookies to this file */
  bool cookiesession;   /* new cookie session? */
  bool crlf;            /* convert crlf on ftp upload(?) */
  char *ftp_account;    /* ftp account data */
  char *ftp_alternative_to_user;   /* command to send if USER/PASS fails */
  struct curl_slist *quote;     /* after connection is established */
  struct curl_slist *postquote; /* after the transfer */
  struct curl_slist *prequote; /* before the transfer, after type */
  struct curl_slist *source_quote;  /* 3rd party quote */
  struct curl_slist *source_prequote;  /* in 3rd party transfer mode - before
                                          the transfer on source host */
  struct curl_slist *source_postquote; /* in 3rd party transfer mode - after
                                          the transfer on source host */
  struct curl_slist *telnet_options; /* linked list of telnet options */
  curl_TimeCond timecondition; /* kind of time/date comparison */
  time_t timevalue;       /* what time to compare with */
  curl_closepolicy closepolicy; /* connection cache close concept */
  Curl_HttpReq httpreq;   /* what kind of HTTP request (if any) is this */
  char *customrequest;    /* HTTP/FTP request to use */
  long httpversion; /* when non-zero, a specific HTTP version requested to
                       be used in the library's request(s) */
  char *auth_host; /* if set, this is the allocated string to the host name
                    * to which to send the authorization data to, and no other
                    * host (which location-following otherwise could lead to)
                    */
  char *krb4_level; /* what security level */
  struct ssl_config_data ssl;  /* user defined SSL stuff */

  curl_proxytype proxytype; /* what kind of proxy that is in use */

  int dns_cache_timeout; /* DNS cache timeout */
  long buffer_size;      /* size of receive buffer to use */

  char *private_data; /* Private data */

  struct Curl_one_easy *one_easy; /* When adding an easy handle to a multi
                                     handle, an internal 'Curl_one_easy'
                                     struct is created and this is a pointer
                                     to the particular struct associated with
                                     this SessionHandle */

  struct curl_slist *http200aliases; /* linked list of aliases for http200 */

  long ip_version;

  curl_off_t max_filesize; /* Maximum file size to download */

  char *source_url;     /* for 3rd party transfer */
  char *source_userpwd;  /* for 3rd party transfer */

  curl_ftpfile ftp_filemethod; /* how to get to a file when FTP is used  */

/* Here follows boolean settings that define how to behave during
   this session. They are STATIC, set by libcurl users or at least initially
   and they don't change during operations. */

  bool printhost;       /* printing host name in debug info */
  bool get_filetime;
  bool tunnel_thru_httpproxy;
  bool prefer_ascii;    /* ASCII rather than binary */
  bool ftp_append;
  bool ftp_list_only;
  bool ftp_create_missing_dirs;
  bool ftp_use_port;
  bool hide_progress;
  bool http_fail_on_error;
  bool http_follow_location;
  bool http_disable_hostname_check_before_authentication;
  bool include_header;   /* include received protocol headers in data output */
  bool http_set_referer;
  bool http_auto_referer; /* set "correct" referer when following location: */
  bool opt_no_body;      /* as set with CURLOPT_NO_BODY */
  bool set_port;
  bool upload;
  enum CURL_NETRC_OPTION
       use_netrc;        /* defined in include/curl.h */
  char *netrc_file;      /* if not NULL, use this instead of trying to find
                            $HOME/.netrc */
  bool verbose;
  bool krb4;             /* kerberos4 connection requested */
  bool reuse_forbid;     /* forbidden to be reused, close after use */
  bool reuse_fresh;      /* do not re-use an existing connection  */
  bool ftp_use_epsv;     /* if EPSV is to be attempted or not */
  bool ftp_use_eprt;     /* if EPRT is to be attempted or not */
  curl_ftpssl ftp_ssl;   /* if AUTH TLS is to be attempted etc */
  curl_ftpauth ftpsslauth; /* what AUTH XXX to be attempted */
  bool no_signal;        /* do not use any signal/alarm handler */
  bool global_dns_cache; /* subject for future removal */
  bool tcp_nodelay;      /* whether to enable TCP_NODELAY or not */
  bool ignorecl;         /* ignore content length */
  bool ftp_skip_ip;      /* skip the IP address the FTP server passes on to
                            us */
  bool connect_only;     /* make connection, let application use the socket */
};

struct Names {
  struct curl_hash *hostcache;
  enum {
    HCACHE_NONE,    /* not pointing to anything */
    HCACHE_PRIVATE, /* points to our own */
    HCACHE_GLOBAL,  /* points to the (shrug) global one */
    HCACHE_MULTI,   /* points to a shared one in the multi handle */
    HCACHE_SHARED   /* points to a shared one in a shared object */
  } hostcachetype;
};

/*
 * The 'connectdata' struct MUST have all the connection oriented stuff as we
 * may have several simultaneous connections and connection structs in memory.
 *
 * The 'struct UserDefined' must only contain data that is set once to go for
 * many (perhaps) independent connections. Values that are generated or
 * calculated internally for the "session handle" must be defined within the
 * 'struct UrlState' instead.
 */

struct SessionHandle {
  struct Names dns;
  struct Curl_multi *multi;    /* if non-NULL, points to the multi handle
                                  struct to which this "belongs" */
  struct Curl_share *share;    /* Share, handles global variable mutexing */
  struct HandleData reqdata;   /* Request-specific data */
  struct UserDefined set;      /* values set by the libcurl user */
  struct DynamicStatic change; /* possibly modified userdefined data */

  struct CookieInfo *cookies;  /* the cookies, read from files and servers */
  struct Progress progress;    /* for all the progress meter data */
  struct UrlState state;       /* struct for fields used for state info and
                                  other dynamic purposes */
  struct PureInfo info;        /* stats, reports and info data */
#if defined(CURL_DOES_CONVERSIONS) && defined(HAVE_ICONV)
  iconv_t outbound_cd;         /* for translating to the network encoding */
  iconv_t inbound_cd;          /* for translating from the network encoding */
  iconv_t utf8_cd;             /* for translating to UTF8 */
#endif /* CURL_DOES_CONVERSIONS && HAVE_ICONV */
  unsigned int magic;          /* set to a CURLEASY_MAGIC_NUMBER */
};

#define LIBCURL_NAME "libcurl"

#endif