1.\"- 2.\" Copyright (c) 1998-2013 Dag-Erling Smørgrav 3.\" Copyright (c) 2013 Michael Gmelin <freebsd@grem.de> 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" $FreeBSD$ 28.\" 29.Dd October 15, 2014 30.Dt FETCH 3 31.Os 32.Sh NAME 33.Nm fetchMakeURL , 34.Nm fetchParseURL , 35.Nm fetchFreeURL , 36.Nm fetchXGetURL , 37.Nm fetchGetURL , 38.Nm fetchPutURL , 39.Nm fetchStatURL , 40.Nm fetchListURL , 41.Nm fetchXGet , 42.Nm fetchGet , 43.Nm fetchPut , 44.Nm fetchStat , 45.Nm fetchList , 46.Nm fetchXGetFile , 47.Nm fetchGetFile , 48.Nm fetchPutFile , 49.Nm fetchStatFile , 50.Nm fetchListFile , 51.Nm fetchXGetHTTP , 52.Nm fetchGetHTTP , 53.Nm fetchPutHTTP , 54.Nm fetchStatHTTP , 55.Nm fetchListHTTP , 56.Nm fetchXGetFTP , 57.Nm fetchGetFTP , 58.Nm fetchPutFTP , 59.Nm fetchStatFTP , 60.Nm fetchListFTP 61.Nd file transfer functions 62.Sh LIBRARY 63.Lb libfetch 64.Sh SYNOPSIS 65.In sys/param.h 66.In stdio.h 67.In fetch.h 68.Ft struct url * 69.Fn fetchMakeURL "const char *scheme" "const char *host" "int port" "const char *doc" "const char *user" "const char *pwd" 70.Ft struct url * 71.Fn fetchParseURL "const char *URL" 72.Ft void 73.Fn fetchFreeURL "struct url *u" 74.Ft FILE * 75.Fn fetchXGetURL "const char *URL" "struct url_stat *us" "const char *flags" 76.Ft FILE * 77.Fn fetchGetURL "const char *URL" "const char *flags" 78.Ft FILE * 79.Fn fetchPutURL "const char *URL" "const char *flags" 80.Ft int 81.Fn fetchStatURL "const char *URL" "struct url_stat *us" "const char *flags" 82.Ft struct url_ent * 83.Fn fetchListURL "const char *URL" "const char *flags" 84.Ft FILE * 85.Fn fetchXGet "struct url *u" "struct url_stat *us" "const char *flags" 86.Ft FILE * 87.Fn fetchGet "struct url *u" "const char *flags" 88.Ft FILE * 89.Fn fetchPut "struct url *u" "const char *flags" 90.Ft int 91.Fn fetchStat "struct url *u" "struct url_stat *us" "const char *flags" 92.Ft struct url_ent * 93.Fn fetchList "struct url *u" "const char *flags" 94.Ft FILE * 95.Fn fetchXGetFile "struct url *u" "struct url_stat *us" "const char *flags" 96.Ft FILE * 97.Fn fetchGetFile "struct url *u" "const char *flags" 98.Ft FILE * 99.Fn fetchPutFile "struct url *u" "const char *flags" 100.Ft int 101.Fn fetchStatFile "struct url *u" "struct url_stat *us" "const char *flags" 102.Ft struct url_ent * 103.Fn fetchListFile "struct url *u" "const char *flags" 104.Ft FILE * 105.Fn fetchXGetHTTP "struct url *u" "struct url_stat *us" "const char *flags" 106.Ft FILE * 107.Fn fetchGetHTTP "struct url *u" "const char *flags" 108.Ft FILE * 109.Fn fetchPutHTTP "struct url *u" "const char *flags" 110.Ft int 111.Fn fetchStatHTTP "struct url *u" "struct url_stat *us" "const char *flags" 112.Ft struct url_ent * 113.Fn fetchListHTTP "struct url *u" "const char *flags" 114.Ft FILE * 115.Fn fetchXGetFTP "struct url *u" "struct url_stat *us" "const char *flags" 116.Ft FILE * 117.Fn fetchGetFTP "struct url *u" "const char *flags" 118.Ft FILE * 119.Fn fetchPutFTP "struct url *u" "const char *flags" 120.Ft int 121.Fn fetchStatFTP "struct url *u" "struct url_stat *us" "const char *flags" 122.Ft struct url_ent * 123.Fn fetchListFTP "struct url *u" "const char *flags" 124.Sh DESCRIPTION 125These functions implement a high-level library for retrieving and 126uploading files using Uniform Resource Locators (URLs). 127.Pp 128.Fn fetchParseURL 129takes a URL in the form of a null-terminated string and splits it into 130its components function according to the Common Internet Scheme Syntax 131detailed in RFC1738. 132A regular expression which produces this syntax is: 133.Bd -literal 134 <scheme>:(//(<user>(:<pwd>)?@)?<host>(:<port>)?)?/(<document>)? 135.Ed 136.Pp 137If the URL does not seem to begin with a scheme name, the following 138syntax is assumed: 139.Bd -literal 140 ((<user>(:<pwd>)?@)?<host>(:<port>)?)?/(<document>)? 141.Ed 142.Pp 143Note that some components of the URL are not necessarily relevant to 144all URL schemes. 145For instance, the file scheme only needs the <scheme> and <document> 146components. 147.Pp 148.Fn fetchMakeURL 149and 150.Fn fetchParseURL 151return a pointer to a 152.Vt url 153structure, which is defined as follows in 154.In fetch.h : 155.Bd -literal 156#define URL_SCHEMELEN 16 157#define URL_USERLEN 256 158#define URL_PWDLEN 256 159 160struct url { 161 char scheme[URL_SCHEMELEN+1]; 162 char user[URL_USERLEN+1]; 163 char pwd[URL_PWDLEN+1]; 164 char host[MAXHOSTNAMELEN+1]; 165 int port; 166 char *doc; 167 off_t offset; 168 size_t length; 169 time_t ims_time; 170}; 171.Ed 172.Pp 173The 174.Va ims_time 175field stores the time value for 176.Li If-Modified-Since 177HTTP requests. 178.Pp 179The pointer returned by 180.Fn fetchMakeURL 181or 182.Fn fetchParseURL 183should be freed using 184.Fn fetchFreeURL . 185.Pp 186.Fn fetchXGetURL , 187.Fn fetchGetURL , 188and 189.Fn fetchPutURL 190constitute the recommended interface to the 191.Nm fetch 192library. 193They examine the URL passed to them to determine the transfer 194method, and call the appropriate lower-level functions to perform the 195actual transfer. 196.Fn fetchXGetURL 197also returns the remote document's metadata in the 198.Vt url_stat 199structure pointed to by the 200.Fa us 201argument. 202.Pp 203The 204.Fa flags 205argument is a string of characters which specify transfer options. 206The 207meaning of the individual flags is scheme-dependent, and is detailed 208in the appropriate section below. 209.Pp 210.Fn fetchStatURL 211attempts to obtain the requested document's metadata and fill in the 212structure pointed to by its second argument. 213The 214.Vt url_stat 215structure is defined as follows in 216.In fetch.h : 217.Bd -literal 218struct url_stat { 219 off_t size; 220 time_t atime; 221 time_t mtime; 222}; 223.Ed 224.Pp 225If the size could not be obtained from the server, the 226.Fa size 227field is set to -1. 228If the modification time could not be obtained from the server, the 229.Fa mtime 230field is set to the epoch. 231If the access time could not be obtained from the server, the 232.Fa atime 233field is set to the modification time. 234.Pp 235.Fn fetchListURL 236attempts to list the contents of the directory pointed to by the URL 237provided. 238If successful, it returns a malloced array of 239.Vt url_ent 240structures. 241The 242.Vt url_ent 243structure is defined as follows in 244.In fetch.h : 245.Bd -literal 246struct url_ent { 247 char name[PATH_MAX]; 248 struct url_stat stat; 249}; 250.Ed 251.Pp 252The list is terminated by an entry with an empty name. 253.Pp 254The pointer returned by 255.Fn fetchListURL 256should be freed using 257.Fn free . 258.Pp 259.Fn fetchXGet , 260.Fn fetchGet , 261.Fn fetchPut 262and 263.Fn fetchStat 264are similar to 265.Fn fetchXGetURL , 266.Fn fetchGetURL , 267.Fn fetchPutURL 268and 269.Fn fetchStatURL , 270except that they expect a pre-parsed URL in the form of a pointer to 271a 272.Vt struct url 273rather than a string. 274.Pp 275All of the 276.Fn fetchXGetXXX , 277.Fn fetchGetXXX 278and 279.Fn fetchPutXXX 280functions return a pointer to a stream which can be used to read or 281write data from or to the requested document, respectively. 282Note that 283although the implementation details of the individual access methods 284vary, it can generally be assumed that a stream returned by one of the 285.Fn fetchXGetXXX 286or 287.Fn fetchGetXXX 288functions is read-only, and that a stream returned by one of the 289.Fn fetchPutXXX 290functions is write-only. 291.Sh FILE SCHEME 292.Fn fetchXGetFile , 293.Fn fetchGetFile 294and 295.Fn fetchPutFile 296provide access to documents which are files in a locally mounted file 297system. 298Only the <document> component of the URL is used. 299.Pp 300.Fn fetchXGetFile 301and 302.Fn fetchGetFile 303do not accept any flags. 304.Pp 305.Fn fetchPutFile 306accepts the 307.Ql a 308(append to file) flag. 309If that flag is specified, the data written to 310the stream returned by 311.Fn fetchPutFile 312will be appended to the previous contents of the file, instead of 313replacing them. 314.Sh FTP SCHEME 315.Fn fetchXGetFTP , 316.Fn fetchGetFTP 317and 318.Fn fetchPutFTP 319implement the FTP protocol as described in RFC959. 320.Pp 321If the 322.Ql P 323(not passive) flag is specified, an active (rather than passive) 324connection will be attempted. 325.Pp 326The 327.Ql p 328flag is supported for compatibility with earlier versions where active 329connections were the default. 330It has precedence over the 331.Ql P 332flag, so if both are specified, 333.Nm 334will use a passive connection. 335.Pp 336If the 337.Ql l 338(low) flag is specified, data sockets will be allocated in the low (or 339default) port range instead of the high port range (see 340.Xr ip 4 ) . 341.Pp 342If the 343.Ql d 344(direct) flag is specified, 345.Fn fetchXGetFTP , 346.Fn fetchGetFTP 347and 348.Fn fetchPutFTP 349will use a direct connection even if a proxy server is defined. 350.Pp 351If no user name or password is given, the 352.Nm fetch 353library will attempt an anonymous login, with user name "anonymous" 354and password "anonymous@<hostname>". 355.Sh HTTP SCHEME 356The 357.Fn fetchXGetHTTP , 358.Fn fetchGetHTTP 359and 360.Fn fetchPutHTTP 361functions implement the HTTP/1.1 protocol. 362With a little luck, there is 363even a chance that they comply with RFC2616 and RFC2617. 364.Pp 365If the 366.Ql d 367(direct) flag is specified, 368.Fn fetchXGetHTTP , 369.Fn fetchGetHTTP 370and 371.Fn fetchPutHTTP 372will use a direct connection even if a proxy server is defined. 373.Pp 374If the 375.Ql i 376(if-modified-since) flag is specified, and 377the 378.Va ims_time 379field is set in 380.Vt "struct url" , 381then 382.Fn fetchXGetHTTP 383and 384.Fn fetchGetHTTP 385will send a conditional 386.Li If-Modified-Since 387HTTP header to only fetch the content if it is newer than 388.Va ims_time . 389.Pp 390Since there seems to be no good way of implementing the HTTP PUT 391method in a manner consistent with the rest of the 392.Nm fetch 393library, 394.Fn fetchPutHTTP 395is currently unimplemented. 396.Sh HTTPS SCHEME 397Based on HTTP SCHEME. 398By default the peer is verified using the CA bundle located in 399.Pa /etc/ssl/cert.pem . 400The file may contain multiple CA certificates. 401A common source of a current CA bundle is 402.Pa \%security/ca_root_nss . 403.Pp 404The CA bundle used for peer verification can be changed by setting the 405environment variables 406.Ev SSL_CA_CERT_FILE 407to point to a concatenated bundle of trusted certificates and 408.Ev SSL_CA_CERT_PATH 409to point to a directory containing hashes of trusted CAs (see 410.Xr verify 1 ) . 411.Pp 412A certificate revocation list (CRL) can be used by setting the 413environment variable 414.Ev SSL_CRL_FILE 415(see 416.Xr crl 1 ) . 417.Pp 418Peer verification can be disabled by setting the environment variable 419.Ev SSL_NO_VERIFY_PEER . 420Note that this also disables CRL checking. 421.Pp 422By default the service identity is verified according to the rules 423detailed in RFC6125 (also known as hostname verification). 424This feature can be disabled by setting the environment variable 425.Ev SSL_NO_VERIFY_HOSTNAME . 426.Pp 427Client certificate based authentication is supported. 428The environment variable 429.Ev SSL_CLIENT_CERT_FILE 430should be set to point to a file containing key and client certificate 431to be used in PEM format. In case the key is stored in a separate 432file, the environment variable 433.Ev SSL_CLIENT_KEY_FILE 434can be set to point to the key in PEM format. 435In case the key uses a password, the user will be prompted on standard 436input (see 437.Xr PEM 3 ) . 438.Pp 439By default 440.Nm libfetch 441allows TLSv1 and newer when negotiating the connecting with the remote 442peer. 443You can change this behavior by setting the 444.Ev SSL_ALLOW_SSL2 445and 446.Ev SSL_ALLOW_SSL3 447environment variables to allow SSLv2 and SSLv3, respectively, and 448.Ev SSL_NO_TLS1 , 449.Ev SSL_NO_TLS1_1 and 450.Ev SSL_NO_TLS1_2 451to disable TLS 1.0, 1.1 and 1.2 respectively. 452.Sh AUTHENTICATION 453Apart from setting the appropriate environment variables and 454specifying the user name and password in the URL or the 455.Vt struct url , 456the calling program has the option of defining an authentication 457function with the following prototype: 458.Pp 459.Ft int 460.Fn myAuthMethod "struct url *u" 461.Pp 462The callback function should fill in the 463.Fa user 464and 465.Fa pwd 466fields in the provided 467.Vt struct url 468and return 0 on success, or any other value to indicate failure. 469.Pp 470To register the authentication callback, simply set 471.Va fetchAuthMethod 472to point at it. 473The callback will be used whenever a site requires authentication and 474the appropriate environment variables are not set. 475.Pp 476This interface is experimental and may be subject to change. 477.Sh RETURN VALUES 478.Fn fetchParseURL 479returns a pointer to a 480.Vt struct url 481containing the individual components of the URL. 482If it is 483unable to allocate memory, or the URL is syntactically incorrect, 484.Fn fetchParseURL 485returns a NULL pointer. 486.Pp 487The 488.Fn fetchStat 489functions return 0 on success and -1 on failure. 490.Pp 491All other functions return a stream pointer which may be used to 492access the requested document, or NULL if an error occurred. 493.Pp 494The following error codes are defined in 495.In fetch.h : 496.Bl -tag -width 18n 497.It Bq Er FETCH_ABORT 498Operation aborted 499.It Bq Er FETCH_AUTH 500Authentication failed 501.It Bq Er FETCH_DOWN 502Service unavailable 503.It Bq Er FETCH_EXISTS 504File exists 505.It Bq Er FETCH_FULL 506File system full 507.It Bq Er FETCH_INFO 508Informational response 509.It Bq Er FETCH_MEMORY 510Insufficient memory 511.It Bq Er FETCH_MOVED 512File has moved 513.It Bq Er FETCH_NETWORK 514Network error 515.It Bq Er FETCH_OK 516No error 517.It Bq Er FETCH_PROTO 518Protocol error 519.It Bq Er FETCH_RESOLV 520Resolver error 521.It Bq Er FETCH_SERVER 522Server error 523.It Bq Er FETCH_TEMP 524Temporary error 525.It Bq Er FETCH_TIMEOUT 526Operation timed out 527.It Bq Er FETCH_UNAVAIL 528File is not available 529.It Bq Er FETCH_UNKNOWN 530Unknown error 531.It Bq Er FETCH_URL 532Invalid URL 533.El 534.Pp 535The accompanying error message includes a protocol-specific error code 536and message, e.g.\& "File is not available (404 Not Found)" 537.Sh ENVIRONMENT 538.Bl -tag -width ".Ev FETCH_BIND_ADDRESS" 539.It Ev FETCH_BIND_ADDRESS 540Specifies a hostname or IP address to which sockets used for outgoing 541connections will be bound. 542.It Ev FTP_LOGIN 543Default FTP login if none was provided in the URL. 544.It Ev FTP_PASSIVE_MODE 545If set to 546.Ql no , 547forces the FTP code to use active mode. 548If set to any other value, forces passive mode even if the application 549requested active mode. 550.It Ev FTP_PASSWORD 551Default FTP password if the remote server requests one and none was 552provided in the URL. 553.It Ev FTP_PROXY 554URL of the proxy to use for FTP requests. 555The document part is ignored. 556FTP and HTTP proxies are supported; if no scheme is specified, FTP is 557assumed. 558If the proxy is an FTP proxy, 559.Nm libfetch 560will send 561.Ql user@host 562as user name to the proxy, where 563.Ql user 564is the real user name, and 565.Ql host 566is the name of the FTP server. 567.Pp 568If this variable is set to an empty string, no proxy will be used for 569FTP requests, even if the 570.Ev HTTP_PROXY 571variable is set. 572.It Ev ftp_proxy 573Same as 574.Ev FTP_PROXY , 575for compatibility. 576.It Ev HTTP_ACCEPT 577Specifies the value of the 578.Va Accept 579header for HTTP requests. 580If empty, no 581.Va Accept 582header is sent. 583The default is 584.Dq */* . 585.It Ev HTTP_AUTH 586Specifies HTTP authorization parameters as a colon-separated list of 587items. 588The first and second item are the authorization scheme and realm 589respectively; further items are scheme-dependent. 590Currently, the 591.Dq basic 592and 593.Dq digest 594authorization methods are supported. 595.Pp 596Both methods require two parameters: the user name and 597password, in that order. 598.Pp 599This variable is only used if the server requires authorization and 600no user name or password was specified in the URL. 601.It Ev HTTP_PROXY 602URL of the proxy to use for HTTP requests. 603The document part is ignored. 604Only HTTP proxies are supported for HTTP requests. 605If no port number is specified, the default is 3128. 606.Pp 607Note that this proxy will also be used for FTP documents, unless the 608.Ev FTP_PROXY 609variable is set. 610.It Ev http_proxy 611Same as 612.Ev HTTP_PROXY , 613for compatibility. 614.It Ev HTTP_PROXY_AUTH 615Specifies authorization parameters for the HTTP proxy in the same 616format as the 617.Ev HTTP_AUTH 618variable. 619.Pp 620This variable is used if and only if connected to an HTTP proxy, and 621is ignored if a user and/or a password were specified in the proxy 622URL. 623.It Ev HTTP_REFERER 624Specifies the referrer URL to use for HTTP requests. 625If set to 626.Dq auto , 627the document URL will be used as referrer URL. 628.It Ev HTTP_USER_AGENT 629Specifies the User-Agent string to use for HTTP requests. 630This can be useful when working with HTTP origin or proxy servers that 631differentiate between user agents. 632If defined but empty, no User-Agent header is sent. 633.It Ev NETRC 634Specifies a file to use instead of 635.Pa ~/.netrc 636to look up login names and passwords for FTP sites. 637See 638.Xr ftp 1 639for a description of the file format. 640This feature is experimental. 641.It Ev NO_PROXY 642Either a single asterisk, which disables the use of proxies 643altogether, or a comma- or whitespace-separated list of hosts for 644which proxies should not be used. 645.It Ev no_proxy 646Same as 647.Ev NO_PROXY , 648for compatibility. 649.It Ev SSL_ALLOW_SSL2 650Allow SSL version 2 when negotiating the connection (not recommended). 651.It Ev SSL_ALLOW_SSL3 652Allow SSL version 3 when negotiating the connection (not recommended). 653.It Ev SSL_CA_CERT_FILE 654CA certificate bundle containing trusted CA certificates. 655Default value: 656.Pa /etc/ssl/cert.pem . 657.It Ev SSL_CA_CERT_PATH 658Path containing trusted CA hashes. 659.It Ev SSL_CLIENT_CERT_FILE 660PEM encoded client certificate/key which will be used in 661client certificate authentication. 662.It Ev SSL_CLIENT_KEY_FILE 663PEM encoded client key in case key and client certificate 664are stored separately. 665.It Ev SSL_CRL_FILE 666File containing certificate revocation list. 667.It Ev SSL_NO_TLS1 668Do not allow TLS version 1.0 when negotiating the connection. 669.It Ev SSL_NO_TLS1_1 670Do not allow TLS version 1.1 when negotiating the connection. 671.It Ev SSL_NO_TLS1_2 672Do not allow TLS version 1.2 when negotiating the connection. 673.It Ev SSL_NO_VERIFY_HOSTNAME 674If set, do not verify that the hostname matches the subject of the 675certificate presented by the server. 676.It Ev SSL_NO_VERIFY_PEER 677If set, do not verify the peer certificate against trusted CAs. 678.El 679.Sh EXAMPLES 680To access a proxy server on 681.Pa proxy.example.com 682port 8080, set the 683.Ev HTTP_PROXY 684environment variable in a manner similar to this: 685.Pp 686.Dl HTTP_PROXY=http://proxy.example.com:8080 687.Pp 688If the proxy server requires authentication, there are 689two options available for passing the authentication data. 690The first method is by using the proxy URL: 691.Pp 692.Dl HTTP_PROXY=http://<user>:<pwd>@proxy.example.com:8080 693.Pp 694The second method is by using the 695.Ev HTTP_PROXY_AUTH 696environment variable: 697.Bd -literal -offset indent 698HTTP_PROXY=http://proxy.example.com:8080 699HTTP_PROXY_AUTH=basic:*:<user>:<pwd> 700.Ed 701.Pp 702To disable the use of a proxy for an HTTP server running on the local 703host, define 704.Ev NO_PROXY 705as follows: 706.Bd -literal -offset indent 707NO_PROXY=localhost,127.0.0.1 708.Ed 709.Pp 710Access HTTPS website without any certificate verification whatsoever: 711.Bd -literal -offset indent 712SSL_NO_VERIFY_PEER=1 713SSL_NO_VERIFY_HOSTNAME=1 714.Ed 715.Pp 716Access HTTPS website using client certificate based authentication 717and a private CA: 718.Bd -literal -offset indent 719SSL_CLIENT_CERT_FILE=/path/to/client.pem 720SSL_CA_CERT_FILE=/path/to/myca.pem 721.Ed 722.Sh SEE ALSO 723.Xr fetch 1 , 724.Xr ftpio 3 , 725.Xr ip 4 726.Rs 727.%A J. Postel 728.%A J. K. Reynolds 729.%D October 1985 730.%B File Transfer Protocol 731.%O RFC959 732.Re 733.Rs 734.%A P. Deutsch 735.%A A. Emtage 736.%A A. Marine. 737.%D May 1994 738.%T How to Use Anonymous FTP 739.%O RFC1635 740.Re 741.Rs 742.%A T. Berners-Lee 743.%A L. Masinter 744.%A M. McCahill 745.%D December 1994 746.%T Uniform Resource Locators (URL) 747.%O RFC1738 748.Re 749.Rs 750.%A R. Fielding 751.%A J. Gettys 752.%A J. Mogul 753.%A H. Frystyk 754.%A L. Masinter 755.%A P. Leach 756.%A T. Berners-Lee 757.%D January 1999 758.%B Hypertext Transfer Protocol -- HTTP/1.1 759.%O RFC2616 760.Re 761.Rs 762.%A J. Franks 763.%A P. Hallam-Baker 764.%A J. Hostetler 765.%A S. Lawrence 766.%A P. Leach 767.%A A. Luotonen 768.%A L. Stewart 769.%D June 1999 770.%B HTTP Authentication: Basic and Digest Access Authentication 771.%O RFC2617 772.Re 773.Sh HISTORY 774The 775.Nm fetch 776library first appeared in 777.Fx 3.0 . 778.Sh AUTHORS 779.An -nosplit 780The 781.Nm fetch 782library was mostly written by 783.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org 784with numerous suggestions and contributions from 785.An Jordan K. Hubbard Aq Mt jkh@FreeBSD.org , 786.An Eugene Skepner Aq Mt eu@qub.com , 787.An Hajimu Umemoto Aq Mt ume@FreeBSD.org , 788.An Henry Whincup Aq Mt henry@techiebod.com , 789.An Jukka A. Ukkonen Aq Mt jau@iki.fi , 790.An Jean-Fran\(,cois Dockes Aq Mt jf@dockes.org , 791.An Michael Gmelin Aq Mt freebsd@grem.de 792and others. 793It replaces the older 794.Nm ftpio 795library written by 796.An Poul-Henning Kamp Aq Mt phk@FreeBSD.org 797and 798.An Jordan K. Hubbard Aq Mt jkh@FreeBSD.org . 799.Pp 800This manual page was written by 801.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org 802and 803.An Michael Gmelin Aq Mt freebsd@grem.de . 804.Sh BUGS 805Some parts of the library are not yet implemented. 806The most notable 807examples of this are 808.Fn fetchPutHTTP , 809.Fn fetchListHTTP , 810.Fn fetchListFTP 811and FTP proxy support. 812.Pp 813There is no way to select a proxy at run-time other than setting the 814.Ev HTTP_PROXY 815or 816.Ev FTP_PROXY 817environment variables as appropriate. 818.Pp 819.Nm libfetch 820does not understand or obey 305 (Use Proxy) replies. 821.Pp 822Error numbers are unique only within a certain context; the error 823codes used for FTP and HTTP overlap, as do those used for resolver and 824system errors. 825For instance, error code 202 means "Command not 826implemented, superfluous at this site" in an FTP context and 827"Accepted" in an HTTP context. 828.Pp 829.Fn fetchStatFTP 830does not check that the result of an MDTM command is a valid date. 831.Pp 832In case password protected keys are used for client certificate based 833authentication the user is prompted for the password on each and every 834fetch operation. 835.Pp 836The man page is incomplete, poorly written and produces badly 837formatted text. 838.Pp 839The error reporting mechanism is unsatisfactory. 840.Pp 841Some parts of the code are not fully reentrant. 842