1.\"- 2.\" Copyright (c) 1998-2013 Dag-Erling Smørgrav 3.\" Copyright (c) 2013-2016 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 March 18, 2016 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 /usr/local/etc/ssl/cert.pem . 400If this file does not exist, 401.Pa /etc/ssl/cert.pem 402is used instead. 403If neither file exists, and 404.Ev SSL_CA_CERT_PATH 405has not been set, 406OpenSSL's default CA cert and path settings apply. 407The certificate bundle can contain multiple CA certificates. 408A common source of a current CA bundle is 409.Pa \%security/ca_root_nss . 410.Pp 411The CA bundle used for peer verification can be changed by setting the 412environment variables 413.Ev SSL_CA_CERT_FILE 414to point to a concatenated bundle of trusted certificates and 415.Ev SSL_CA_CERT_PATH 416to point to a directory containing hashes of trusted CAs (see 417.Xr verify 1 ) . 418.Pp 419A certificate revocation list (CRL) can be used by setting the 420environment variable 421.Ev SSL_CRL_FILE 422(see 423.Xr crl 1 ) . 424.Pp 425Peer verification can be disabled by setting the environment variable 426.Ev SSL_NO_VERIFY_PEER . 427Note that this also disables CRL checking. 428.Pp 429By default the service identity is verified according to the rules 430detailed in RFC6125 (also known as hostname verification). 431This feature can be disabled by setting the environment variable 432.Ev SSL_NO_VERIFY_HOSTNAME . 433.Pp 434Client certificate based authentication is supported. 435The environment variable 436.Ev SSL_CLIENT_CERT_FILE 437should be set to point to a file containing key and client certificate 438to be used in PEM format. 439When a PEM-format key is in a separate file from the client certificate, 440the environment variable 441.Ev SSL_CLIENT_KEY_FILE 442can be set to point to the key file. 443In case the key uses a password, the user will be prompted on standard 444input (see 445.Xr PEM 3 ) . 446.Pp 447By default 448.Nm libfetch 449allows TLSv1 and newer when negotiating the connecting with the remote 450peer. 451You can change this behavior by setting the 452.Ev SSL_ALLOW_SSL3 453environment variable to allow SSLv3 and 454.Ev SSL_NO_TLS1 , 455.Ev SSL_NO_TLS1_1 and 456.Ev SSL_NO_TLS1_2 457to disable TLS 1.0, 1.1 and 1.2 respectively. 458.Sh AUTHENTICATION 459Apart from setting the appropriate environment variables and 460specifying the user name and password in the URL or the 461.Vt struct url , 462the calling program has the option of defining an authentication 463function with the following prototype: 464.Pp 465.Ft int 466.Fn myAuthMethod "struct url *u" 467.Pp 468The callback function should fill in the 469.Fa user 470and 471.Fa pwd 472fields in the provided 473.Vt struct url 474and return 0 on success, or any other value to indicate failure. 475.Pp 476To register the authentication callback, simply set 477.Va fetchAuthMethod 478to point at it. 479The callback will be used whenever a site requires authentication and 480the appropriate environment variables are not set. 481.Pp 482This interface is experimental and may be subject to change. 483.Sh RETURN VALUES 484.Fn fetchParseURL 485returns a pointer to a 486.Vt struct url 487containing the individual components of the URL. 488If it is 489unable to allocate memory, or the URL is syntactically incorrect, 490.Fn fetchParseURL 491returns a NULL pointer. 492.Pp 493The 494.Fn fetchStat 495functions return 0 on success and -1 on failure. 496.Pp 497All other functions return a stream pointer which may be used to 498access the requested document, or NULL if an error occurred. 499.Pp 500The following error codes are defined in 501.In fetch.h : 502.Bl -tag -width 18n 503.It Bq Er FETCH_ABORT 504Operation aborted 505.It Bq Er FETCH_AUTH 506Authentication failed 507.It Bq Er FETCH_DOWN 508Service unavailable 509.It Bq Er FETCH_EXISTS 510File exists 511.It Bq Er FETCH_FULL 512File system full 513.It Bq Er FETCH_INFO 514Informational response 515.It Bq Er FETCH_MEMORY 516Insufficient memory 517.It Bq Er FETCH_MOVED 518File has moved 519.It Bq Er FETCH_NETWORK 520Network error 521.It Bq Er FETCH_OK 522No error 523.It Bq Er FETCH_PROTO 524Protocol error 525.It Bq Er FETCH_RESOLV 526Resolver error 527.It Bq Er FETCH_SERVER 528Server error 529.It Bq Er FETCH_TEMP 530Temporary error 531.It Bq Er FETCH_TIMEOUT 532Operation timed out 533.It Bq Er FETCH_UNAVAIL 534File is not available 535.It Bq Er FETCH_UNKNOWN 536Unknown error 537.It Bq Er FETCH_URL 538Invalid URL 539.El 540.Pp 541The accompanying error message includes a protocol-specific error code 542and message, like "File is not available (404 Not Found)" 543.Sh ENVIRONMENT 544.Bl -tag -width ".Ev FETCH_BIND_ADDRESS" 545.It Ev FETCH_BIND_ADDRESS 546Specifies a hostname or IP address to which sockets used for outgoing 547connections will be bound. 548.It Ev FTP_LOGIN 549Default FTP login if none was provided in the URL. 550.It Ev FTP_PASSIVE_MODE 551If set to 552.Ql no , 553forces the FTP code to use active mode. 554If set to any other value, forces passive mode even if the application 555requested active mode. 556.It Ev FTP_PASSWORD 557Default FTP password if the remote server requests one and none was 558provided in the URL. 559.It Ev FTP_PROXY 560URL of the proxy to use for FTP requests. 561The document part is ignored. 562FTP and HTTP proxies are supported; if no scheme is specified, FTP is 563assumed. 564If the proxy is an FTP proxy, 565.Nm libfetch 566will send 567.Ql user@host 568as user name to the proxy, where 569.Ql user 570is the real user name, and 571.Ql host 572is the name of the FTP server. 573.Pp 574If this variable is set to an empty string, no proxy will be used for 575FTP requests, even if the 576.Ev HTTP_PROXY 577variable is set. 578.It Ev ftp_proxy 579Same as 580.Ev FTP_PROXY , 581for compatibility. 582.It Ev HTTP_ACCEPT 583Specifies the value of the 584.Va Accept 585header for HTTP requests. 586If empty, no 587.Va Accept 588header is sent. 589The default is 590.Dq */* . 591.It Ev HTTP_AUTH 592Specifies HTTP authorization parameters as a colon-separated list of 593items. 594The first and second item are the authorization scheme and realm 595respectively; further items are scheme-dependent. 596Currently, the 597.Dq basic 598and 599.Dq digest 600authorization methods are supported. 601.Pp 602Both methods require two parameters: the user name and 603password, in that order. 604.Pp 605This variable is only used if the server requires authorization and 606no user name or password was specified in the URL. 607.It Ev HTTP_PROXY 608URL of the proxy to use for HTTP requests. 609The document part is ignored. 610Only HTTP proxies are supported for HTTP requests. 611If no port number is specified, the default is 3128. 612.Pp 613Note that this proxy will also be used for FTP documents, unless the 614.Ev FTP_PROXY 615variable is set. 616.It Ev http_proxy 617Same as 618.Ev HTTP_PROXY , 619for compatibility. 620.It Ev HTTP_PROXY_AUTH 621Specifies authorization parameters for the HTTP proxy in the same 622format as the 623.Ev HTTP_AUTH 624variable. 625.Pp 626This variable is used if and only if connected to an HTTP proxy, and 627is ignored if a user and/or a password were specified in the proxy 628URL. 629.It Ev HTTP_REFERER 630Specifies the referrer URL to use for HTTP requests. 631If set to 632.Dq auto , 633the document URL will be used as referrer URL. 634.It Ev HTTP_USER_AGENT 635Specifies the User-Agent string to use for HTTP requests. 636This can be useful when working with HTTP origin or proxy servers that 637differentiate between user agents. 638If defined but empty, no User-Agent header is sent. 639.It Ev NETRC 640Specifies a file to use instead of 641.Pa ~/.netrc 642to look up login names and passwords for FTP and HTTP sites as well as 643HTTP proxies. 644See 645.Xr ftp 1 646for a description of the file format. 647.It Ev NO_PROXY 648Either a single asterisk, which disables the use of proxies 649altogether, or a comma- or whitespace-separated list of hosts for 650which proxies should not be used. 651.It Ev no_proxy 652Same as 653.Ev NO_PROXY , 654for compatibility. 655.It Ev SSL_ALLOW_SSL3 656Allow SSL version 3 when negotiating the connection (not recommended). 657.It Ev SSL_CA_CERT_FILE 658CA certificate bundle containing trusted CA certificates. 659Default value: See HTTPS SCHEME above. 660.It Ev SSL_CA_CERT_PATH 661Path containing trusted CA hashes. 662.It Ev SSL_CLIENT_CERT_FILE 663PEM encoded client certificate/key which will be used in 664client certificate authentication. 665.It Ev SSL_CLIENT_KEY_FILE 666PEM encoded client key in case key and client certificate 667are stored separately. 668.It Ev SSL_CRL_FILE 669File containing certificate revocation list. 670.It Ev SSL_NO_TLS1 671Do not allow TLS version 1.0 when negotiating the connection. 672.It Ev SSL_NO_TLS1_1 673Do not allow TLS version 1.1 when negotiating the connection. 674.It Ev SSL_NO_TLS1_2 675Do not allow TLS version 1.2 when negotiating the connection. 676.It Ev SSL_NO_VERIFY_HOSTNAME 677If set, do not verify that the hostname matches the subject of the 678certificate presented by the server. 679.It Ev SSL_NO_VERIFY_PEER 680If set, do not verify the peer certificate against trusted CAs. 681.El 682.Sh EXAMPLES 683To access a proxy server on 684.Pa proxy.example.com 685port 8080, set the 686.Ev HTTP_PROXY 687environment variable in a manner similar to this: 688.Pp 689.Dl HTTP_PROXY=http://proxy.example.com:8080 690.Pp 691If the proxy server requires authentication, there are 692two options available for passing the authentication data. 693The first method is by using the proxy URL: 694.Pp 695.Dl HTTP_PROXY=http://<user>:<pwd>@proxy.example.com:8080 696.Pp 697The second method is by using the 698.Ev HTTP_PROXY_AUTH 699environment variable: 700.Bd -literal -offset indent 701HTTP_PROXY=http://proxy.example.com:8080 702HTTP_PROXY_AUTH=basic:*:<user>:<pwd> 703.Ed 704.Pp 705To disable the use of a proxy for an HTTP server running on the local 706host, define 707.Ev NO_PROXY 708as follows: 709.Bd -literal -offset indent 710NO_PROXY=localhost,127.0.0.1 711.Ed 712.Pp 713Access HTTPS website without any certificate verification whatsoever: 714.Bd -literal -offset indent 715SSL_NO_VERIFY_PEER=1 716SSL_NO_VERIFY_HOSTNAME=1 717.Ed 718.Pp 719Access HTTPS website using client certificate based authentication 720and a private CA: 721.Bd -literal -offset indent 722SSL_CLIENT_CERT_FILE=/path/to/client.pem 723SSL_CA_CERT_FILE=/path/to/myca.pem 724.Ed 725.Sh SEE ALSO 726.Xr fetch 1 , 727.Xr ip 4 728.Rs 729.%A J. Postel 730.%A J. K. Reynolds 731.%D October 1985 732.%B File Transfer Protocol 733.%O RFC959 734.Re 735.Rs 736.%A P. Deutsch 737.%A A. Emtage 738.%A A. Marine. 739.%D May 1994 740.%T How to Use Anonymous FTP 741.%O RFC1635 742.Re 743.Rs 744.%A T. Berners-Lee 745.%A L. Masinter 746.%A M. McCahill 747.%D December 1994 748.%T Uniform Resource Locators (URL) 749.%O RFC1738 750.Re 751.Rs 752.%A R. Fielding 753.%A J. Gettys 754.%A J. Mogul 755.%A H. Frystyk 756.%A L. Masinter 757.%A P. Leach 758.%A T. Berners-Lee 759.%D January 1999 760.%B Hypertext Transfer Protocol -- HTTP/1.1 761.%O RFC2616 762.Re 763.Rs 764.%A J. Franks 765.%A P. Hallam-Baker 766.%A J. Hostetler 767.%A S. Lawrence 768.%A P. Leach 769.%A A. Luotonen 770.%A L. Stewart 771.%D June 1999 772.%B HTTP Authentication: Basic and Digest Access Authentication 773.%O RFC2617 774.Re 775.Sh HISTORY 776The 777.Nm fetch 778library first appeared in 779.Fx 3.0 . 780.Sh AUTHORS 781.An -nosplit 782The 783.Nm fetch 784library was mostly written by 785.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org 786with numerous suggestions and contributions from 787.An Jordan K. Hubbard Aq Mt jkh@FreeBSD.org , 788.An Eugene Skepner Aq Mt eu@qub.com , 789.An Hajimu Umemoto Aq Mt ume@FreeBSD.org , 790.An Henry Whincup Aq Mt henry@techiebod.com , 791.An Jukka A. Ukkonen Aq Mt jau@iki.fi , 792.An Jean-Fran\(,cois Dockes Aq Mt jf@dockes.org , 793.An Michael Gmelin Aq Mt freebsd@grem.de 794and others. 795It replaces the older 796.Nm ftpio 797library written by 798.An Poul-Henning Kamp Aq Mt phk@FreeBSD.org 799and 800.An Jordan K. Hubbard Aq Mt jkh@FreeBSD.org . 801.Pp 802This manual page was written by 803.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org 804and 805.An Michael Gmelin Aq Mt freebsd@grem.de . 806.Sh BUGS 807Some parts of the library are not yet implemented. 808The most notable 809examples of this are 810.Fn fetchPutHTTP , 811.Fn fetchListHTTP , 812.Fn fetchListFTP 813and FTP proxy support. 814.Pp 815There is no way to select a proxy at run-time other than setting the 816.Ev HTTP_PROXY 817or 818.Ev FTP_PROXY 819environment variables as appropriate. 820.Pp 821.Nm libfetch 822does not understand or obey 305 (Use Proxy) replies. 823.Pp 824Error numbers are unique only within a certain context; the error 825codes used for FTP and HTTP overlap, as do those used for resolver and 826system errors. 827For instance, error code 202 means "Command not 828implemented, superfluous at this site" in an FTP context and 829"Accepted" in an HTTP context. 830.Pp 831.Fn fetchStatFTP 832does not check that the result of an MDTM command is a valid date. 833.Pp 834In case password protected keys are used for client certificate based 835authentication the user is prompted for the password on each and every 836fetch operation. 837.Pp 838The man page is incomplete, poorly written and produces badly 839formatted text. 840.Pp 841The error reporting mechanism is unsatisfactory. 842.Pp 843Some parts of the code are not fully reentrant. 844