.\" Automatically generated by Pod::Man 2.25 (Pod::Simple 3.16) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. 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No user-serviceable parts. . \" fudge factors for nroff and troff .if n \{\ . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] \fP .\} .if t \{\ . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff .if n \{\ . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} .if t \{\ . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' .ds 8 \h'\*(#H'\(*b\h'-\*(#H' .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] .ds ae a\h'-(\w'a'u*4/10)'e .ds Ae A\h'-(\w'A'u*4/10)'E . \" corrections for vroff .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' . \" for low resolution devices (crt and lpr) .if \n(.H>23 .if \n(.V>19 \ \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} .rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "OSSL_HTTP_TRANSFER 3" .TH OSSL_HTTP_TRANSFER 3 "2020-03-02" "3.0.0-dev" "OpenSSL" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" OSSL_HTTP_get, OSSL_HTTP_get_asn1, OSSL_HTTP_post_asn1, OSSL_HTTP_transfer, OSSL_HTTP_bio_cb_t, OSSL_HTTP_proxy_connect, OSSL_HTTP_parse_url \&\- http client functions .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #include \& \& typedef BIO *(*OSSL_HTTP_bio_cb_t)(BIO *bio, void *arg, \& int connect, int detail); \& BIO *OSSL_HTTP_get(const char *url, const char *proxy, const char *proxy_port, \& BIO *bio, BIO *rbio, \& OSSL_HTTP_bio_cb_t bio_update_fn, void *arg, \& const STACK_OF(CONF_VALUE) *headers, \& int maxline, unsigned long max_resp_len, int timeout, \& const char *expected_content_type, int expect_asn1); \& ASN1_VALUE *OSSL_HTTP_get_asn1(const char *url, \& const char *proxy, const char *proxy_port, \& BIO *bio, BIO *rbio, \& OSSL_HTTP_bio_cb_t bio_update_fn, void *arg, \& const STACK_OF(CONF_VALUE) *headers, \& int maxline, unsigned long max_resp_len, \& int timeout, const char *expected_content_type, \& const ASN1_ITEM *it); \& ASN1_VALUE *OSSL_HTTP_post_asn1(const char *server, const char *port, \& const char *path, int use_ssl, \& const char *proxy, const char *proxy_port, \& BIO *bio, BIO *rbio, \& OSSL_HTTP_bio_cb_t bio_update_fn, void *arg, \& const STACK_OF(CONF_VALUE) *headers, \& const char *content_type, \& ASN1_VALUE *req, const ASN1_ITEM *req_it, \& int maxline, unsigned long max_resp_len, \& int timeout, const char *expected_ct, \& const ASN1_ITEM *rsp_it); \& BIO *OSSL_HTTP_transfer(const char *server, const char *port, const char *path, \& int use_ssl, const char *proxy, const char *proxy_port, \& BIO *bio, BIO *rbio, \& OSSL_HTTP_bio_cb_t bio_update_fn, void *arg, \& const STACK_OF(CONF_VALUE) *headers, \& const char *content_type, BIO *req_mem, \& int maxline, unsigned long max_resp_len, int timeout, \& const char *expected_ct, int expect_asn1, \& char **redirection_url); \& int OSSL_HTTP_proxy_connect(BIO *bio, const char *server, const char *port, \& const char *proxyuser, const char *proxypass, \& int timeout, BIO *bio_err, const char *prog); \& int OSSL_HTTP_parse_url(const char *url, char **phost, char **pport, \& char **ppath, int *pssl); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" \&\fIOSSL_HTTP_get()\fR uses \s-1HTTP\s0 \s-1GET\s0 to obtain data (of any type) from the given \fBurl\fR and returns it as a memory \s-1BIO\s0. .PP \&\fIOSSL_HTTP_get_asn1()\fR uses \s-1HTTP\s0 \s-1GET\s0 to obtain an \s-1ASN\s0.1\-encoded value (e.g., an X.509 certificate) with the expected structure specified by \fBit\fR (e.g., \fIASN1_ITEM_rptr(X509)\fR) from the given \fBurl\fR and returns it on success as a pointer to \fI\s-1ASN1_VALUE\s0\fR. .PP \&\fIOSSL_HTTP_post_asn1()\fR uses the \s-1HTTP\s0 \s-1POST\s0 method to send a request \fBreq\fR with the \s-1ASN\s0.1 structure defined in \fBreq_it\fR and the given \fBcontent_type\fR to the given \fBserver\fR and optional \fBport\fR and \fBpath\fR, which defaults to \*(L"/\*(R". If \fBuse_ssl\fR is nonzero a \s-1TLS\s0 connection is requested and the \fBbio_update_fn\fR parameter, described below, must be provided. The optional list \fBheaders\fR may contain additional custom \s-1HTTP\s0 header lines. The expected structure of the response is specified by \fBrsp_it\fR. On success it returns the response as a pointer to \fB\s-1ASN1_VALUE\s0\fR. .PP \&\fIOSSL_HTTP_transfer()\fR exchanges an \s-1HTTP\s0 request and response with the given \fBserver\fR and optional \fBport\fR and \fBpath\fR, which defaults to \*(L"/\*(R". If \fBuse_ssl\fR is nonzero a \s-1TLS\s0 connection is requested and the \fBbio_update_fn\fR parameter, described below, must be provided. If \fBreq_mem\fR is \s-1NULL\s0 it uses the \s-1HTTP\s0 \s-1GET\s0 method, else it uses \s-1HTTP\s0 \s-1POST\s0 to send a request with the contents of the memory \s-1BIO\s0 and optional \fBcontent_type\fR. The optional list \fBheaders\fR may contain additional custom \s-1HTTP\s0 header lines. If \fBreq_mem\fR is \s-1NULL\s0 (i.e., the \s-1HTTP\s0 method is \s-1GET\s0) and \fBredirection_url\fR is not \s-1NULL\s0 the latter pointer is used to provide any new location that the server may return with \s-1HTTP\s0 code 301 (\s-1MOVED_PERMANENTLY\s0) or 302 (\s-1FOUND\s0). In this case the caller is responsible for deallocating this \s-1URL\s0 with \&\fIOPENSSL_free\fR\|(3). .PP The above functions have the following parameters in common. .PP If the \fBproxy\fR parameter is not \s-1NULL\s0 the \s-1HTTP\s0 client functions connect via the given proxy and the optionally given \fBproxy_port\fR. Proxying plain \s-1HTTP\s0 is supported directly, while using a proxy for \s-1HTTPS\s0 connections requires a suitable callback function such as \fIOSSL_HTTP_proxy_connect()\fR, described below. .PP Typically the \fBbio\fR and \fBrbio\fR parameters are \s-1NULL\s0 and the client creates a network \s-1BIO\s0 internally for connecting to the given server and port (optionally via a proxy and its port), and uses it for exchanging the request and response. If \fBbio\fR is given and \fBrbio\fR is \s-1NULL\s0 then the client uses this \s-1BIO\s0 instead. If both \fBbio\fR and \fBrbio\fR are given (which may be memory BIOs for instance) then no explicit connection is attempted, \&\fBbio\fR is used for writing the request, and \fBrbio\fR for reading the response. As soon as the client has flushed \fBbio\fR the server must be ready to provide a response or indicate a waiting condition via \fBrbio\fR. .PP The \fBmaxline\fR parameter specifies the response header maximum line length, where 0 indicates the default value, which currently is 4k. The \fBmax_resp_len\fR parameter specifies the maximum response length, where 0 indicates the default value, which currently is 100k. .PP An \s-1ASN\s0.1\-encoded response is expected by \fIOSSL_HTTP_get_asn1()\fR and \&\fIOSSL_HTTP_post_asn1()\fR, while for \fIOSSL_HTTP_get()\fR or \fIOSSL_HTTP_transfer()\fR this is only the case if the \fBexpect_asn1\fR parameter is nonzero. If the response header contains one or more Content-Length header lines and/or an \s-1ASN\s0.1\-encoded response is expected, which should include a total length, the length indications received are checked for consistency and for not exceeding the maximum response length. .PP If the parameter \fBexpected_content_type\fR (or \fBexpected_ct\fR, respectively) is not \s-1NULL\s0 then the \s-1HTTP\s0 client checks that the given content type string is included in the \s-1HTTP\s0 header of the response and returns an error if not. .PP If the \fBtimeout\fR parameter is > 0 this indicates the maximum number of seconds to wait until the transfer is complete. A value of 0 enables waiting indefinitely, while a value < 0 immediately leads to a timeout condition. .PP The optional parameter \fBbio_update_fn\fR with its optional argument \fBarg\fR may be used to modify the connection \s-1BIO\s0 used by the \s-1HTTP\s0 client (and cannot be used when both \fBbio\fR and \fBrbio\fR are given). \&\fBbio_update_fn\fR is a \s-1BIO\s0 connect/disconnect callback function with prototype .PP .Vb 1 \& BIO *(*OSSL_HTTP_bio_cb_t)(BIO *bio, void *arg, int connect, int detail) .Ve .PP The callback may modify the \s-1HTTP\s0 \s-1BIO\s0 provided in the \fBbio\fR argument, whereby it may make use of a custom defined argument \fBarg\fR, which may for instance refer to an \fI\s-1SSL_CTX\s0\fR structure. During connection establishment, just after calling \fIBIO_connect_retry()\fR, the function is invoked with the \fBconnect\fR argument being 1 and the \fBdetail\fR argument being 1 if \s-1HTTPS\s0 is requested, i.e., \s-1SSL/TLS\s0 should be enabled. On disconnect \fBconnect\fR is 0 and \fBdetail\fR is 1 if no error occurred, else 0. For instance, on connect the function may prepend a \s-1TLS\s0 \s-1BIO\s0 to implement \s-1HTTPS\s0; after disconnect it may do some diagnostic output and/or specific cleanup. The function should return \s-1NULL\s0 to indicate failure. Here is a simple example that supports \s-1TLS\s0 connections (but not via a proxy): .PP .Vb 3 \& BIO *http_tls_cb(BIO *hbio, void *arg, int connect, int detail) \& { \& SSL_CTX *ctx = (SSL_CTX *)arg; \& \& if (connect && detail) { /* connecting with TLS */ \& BIO *sbio = BIO_new_ssl(ctx, 1); \& hbio = sbio != NULL ? BIO_push(sbio, hbio) : NULL; \& } else if (!connect && !detail) { /* disconnecting after error */ \& /* optionally add diagnostics here */ \& } \& return hbio; \& } .Ve .PP After disconnect the modified \s-1BIO\s0 will be deallocated using \fIBIO_free_all()\fR. .PP \&\fIOSSL_HTTP_proxy_connect()\fR may be used by an above \s-1BIO\s0 connect callback function to set up an \s-1SSL/TLS\s0 connection via an \s-1HTTP\s0 proxy. It promotes the given \s-1BIO\s0 \fBbio\fR representing a connection pre-established with a \s-1TLS\s0 proxy using the \s-1HTTP\s0 \s-1CONNECT\s0 method, optionally using proxy client credentials \fBproxyuser\fR and \fBproxypass\fR, to connect with \s-1TLS\s0 protection ultimately to \fBserver\fR and \fBport\fR. The \fBtimeout\fR parameter is used as described above. Since this function is typically called by appplications such as \&\fIopenssl\-s_client\fR\|(1) it uses the \fBbio_err\fR and \fBprog\fR parameters (unless \&\s-1NULL\s0) to print additional diagnostic information in a user-oriented way. .PP \&\fIOSSL_HTTP_parse_url()\fR parses its input string \fBurl\fR as a \s-1URL\s0 and splits it up into host, port and path components and a flag whether it begins with 'https'. The host component may be a \s-1DNS\s0 name or an IPv4 or an IPv6 address. The port component is optional and defaults to \*(L"443\*(R" for \s-1HTTPS\s0, else \*(L"80\*(R". The path component is also optional and defaults to \*(L"/\*(R". As far as the result pointer arguments are not \s-1NULL\s0 it assigns via them copies of the respective string components. The strings returned this way must be deallocated by the caller using \&\fIOPENSSL_free\fR\|(3) unless they are \s-1NULL\s0, which is their default value on error. .SH "RETURN VALUES" .IX Header "RETURN VALUES" \&\fIOSSL_HTTP_get()\fR, \fIOSSL_HTTP_get_asn1()\fR, \fIOSSL_HTTP_post_asn1()\fR, and \&\fIOSSL_HTTP_transfer()\fR return on success the data received via \s-1HTTP\s0, else \s-1NULL\s0. Error conditions include connection/transfer timeout, parse errors, etc. .PP \&\fIOSSL_HTTP_proxy_connect()\fR and \fIOSSL_HTTP_parse_url()\fR return 1 on success, 0 on error. .SH "HISTORY" .IX Header "HISTORY" \&\fIOSSL_HTTP_get()\fR, \fIOSSL_HTTP_get_asn1()\fR, \fIOSSL_HTTP_post_asn1()\fR, \&\fIOSSL_HTTP_proxy_connect()\fR, and \fIOSSL_HTTP_parse_url()\fR were added in OpenSSL 3.0. .SH "COPYRIGHT" .IX Header "COPYRIGHT" Copyright 2019\-2020 The OpenSSL Project Authors. All Rights Reserved. .PP Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at .