http_client.c
/*
* Copyright 2001-2020 The OpenSSL Project Authors. All Rights Reserved.
* Copyright Siemens AG 2018-2020
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "e_os.h"
#include <stdio.h>
#include <stdlib.h>
#include "crypto/ctype.h"
#include <string.h>
#include <openssl/asn1.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/httperr.h>
#include <openssl/cmperr.h>
#include <openssl/buffer.h>
#include <openssl/http.h>
#include "internal/sockets.h"
#include "internal/cryptlib.h" /* for ossl_assert() */
#include "http_local.h"
#define HTTP_PREFIX "HTTP/"
#define HTTP_VERSION_PATT "1." /* allow 1.x */
#define HTTP_VERSION_STR_LEN 3
#define HTTP_LINE1_MINLEN ((int)strlen(HTTP_PREFIX HTTP_VERSION_PATT "x 200\n"))
#define HTTP_VERSION_MAX_REDIRECTIONS 50
#define HTTP_STATUS_CODE_OK 200
#define HTTP_STATUS_CODE_MOVED_PERMANENTLY 301
#define HTTP_STATUS_CODE_FOUND 302
/* Stateful HTTP request code, supporting blocking and non-blocking I/O */
/* Opaque HTTP request status structure */
struct ossl_http_req_ctx_st {
int state; /* Current I/O state */
unsigned char *iobuf; /* Line buffer */
int iobuflen; /* Line buffer length */
BIO *wbio; /* BIO to send request to */
BIO *rbio; /* BIO to read response from */
BIO *mem; /* Memory BIO response is built into */
int method_GET; /* HTTP method "GET" or "POST" */
const char *expected_ct; /* expected Content-Type, or NULL */
int expect_asn1; /* response must be ASN.1-encoded */
unsigned long resp_len; /* length of response */
unsigned long max_resp_len; /* Maximum length of response */
time_t max_time; /* Maximum end time of the transfer, or 0 */
char *redirection_url; /* Location given with HTTP status 301/302 */
};
#define HTTP_DEFAULT_MAX_LINE_LENGTH (4 * 1024)
#define HTTP_DEFAULT_MAX_RESP_LEN (100 * 1024)
/* HTTP states */
#define OHS_NOREAD 0x1000 /* If set no reading should be performed */
#define OHS_ERROR (0 | OHS_NOREAD) /* Error condition */
#define OHS_FIRSTLINE 1 /* First line being read */
#define OHS_REDIRECT 0xa /* Looking for redirection location */
#define OHS_HEADERS 2 /* MIME headers being read */
#define OHS_ASN1_HEADER 3 /* HTTP initial header (tag+length) being read */
#define OHS_CONTENT 4 /* HTTP content octets being read */
#define OHS_WRITE_INIT (5 | OHS_NOREAD) /* 1st call: ready to start I/O */
#define OHS_WRITE (6 | OHS_NOREAD) /* Request being sent */
#define OHS_FLUSH (7 | OHS_NOREAD) /* Request being flushed */
#define OHS_DONE (8 | OHS_NOREAD) /* Completed */
#define OHS_HTTP_HEADER (9 | OHS_NOREAD) /* Headers set, w/o final \r\n */
OSSL_HTTP_REQ_CTX *OSSL_HTTP_REQ_CTX_new(BIO *wbio, BIO *rbio,
int method_GET, int maxline,
unsigned long max_resp_len,
int timeout,
const char *expected_content_type,
int expect_asn1)
{
OSSL_HTTP_REQ_CTX *rctx;
if (wbio == NULL || rbio == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if ((rctx = OPENSSL_zalloc(sizeof(*rctx))) == NULL)
return NULL;
rctx->state = OHS_ERROR;
rctx->iobuflen = maxline > 0 ? maxline : HTTP_DEFAULT_MAX_LINE_LENGTH;
rctx->iobuf = OPENSSL_malloc(rctx->iobuflen);
rctx->wbio = wbio;
rctx->rbio = rbio;
rctx->mem = BIO_new(BIO_s_mem());
if (rctx->iobuf == NULL || rctx->mem == NULL) {
OSSL_HTTP_REQ_CTX_free(rctx);
return NULL;
}
rctx->method_GET = method_GET;
rctx->expected_ct = expected_content_type;
rctx->expect_asn1 = expect_asn1;
rctx->resp_len = 0;
OSSL_HTTP_REQ_CTX_set_max_response_length(rctx, max_resp_len);
rctx->max_time = timeout > 0 ? time(NULL) + timeout : 0;
return rctx;
}
void OSSL_HTTP_REQ_CTX_free(OSSL_HTTP_REQ_CTX *rctx)
{
if (rctx == NULL)
return;
BIO_free(rctx->mem); /* this may indirectly call ERR_clear_error() */
OPENSSL_free(rctx->iobuf);
OPENSSL_free(rctx);
}
BIO *OSSL_HTTP_REQ_CTX_get0_mem_bio(OSSL_HTTP_REQ_CTX *rctx)
{
if (rctx == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
return rctx->mem;
}
void OSSL_HTTP_REQ_CTX_set_max_response_length(OSSL_HTTP_REQ_CTX *rctx,
unsigned long len)
{
if (rctx == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return;
}
rctx->max_resp_len = len != 0 ? len : HTTP_DEFAULT_MAX_RESP_LEN;
}
/*
* Create HTTP header using given op and path (or "/" in case path is NULL).
* Server name (and port) must be given if and only if plain HTTP proxy is used.
*/
int OSSL_HTTP_REQ_CTX_header(OSSL_HTTP_REQ_CTX *rctx, const char *server,
const char *port, const char *path)
{
if (rctx == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (BIO_printf(rctx->mem, "%s ", rctx->method_GET ? "GET" : "POST") <= 0)
return 0;
if (server != NULL) { /* HTTP (but not HTTPS) proxy is used */
/*
* Section 5.1.2 of RFC 1945 states that the absoluteURI form is only
* allowed when using a proxy
*/
if (BIO_printf(rctx->mem, OSSL_HTTP_PREFIX"%s", server) <= 0)
return 0;
if (port != NULL && BIO_printf(rctx->mem, ":%s", port) <= 0)
return 0;
}
/* Make sure path includes a forward slash */
if (path == NULL)
path = "/";
if (path[0] != '/' && BIO_printf(rctx->mem, "/") <= 0)
return 0;
if (BIO_printf(rctx->mem, "%s "HTTP_PREFIX"1.0\r\n", path) <= 0)
return 0;
rctx->state = OHS_HTTP_HEADER;
return 1;
}
int OSSL_HTTP_REQ_CTX_add1_header(OSSL_HTTP_REQ_CTX *rctx,
const char *name, const char *value)
{
if (rctx == NULL || name == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (BIO_puts(rctx->mem, name) <= 0)
return 0;
if (value != NULL) {
if (BIO_write(rctx->mem, ": ", 2) != 2)
return 0;
if (BIO_puts(rctx->mem, value) <= 0)
return 0;
}
if (BIO_write(rctx->mem, "\r\n", 2) != 2)
return 0;
rctx->state = OHS_HTTP_HEADER;
return 1;
}
static int OSSL_HTTP_REQ_CTX_content(OSSL_HTTP_REQ_CTX *rctx,
const char *content_type, BIO *req_mem)
{
const unsigned char *req;
long req_len;
if (rctx == NULL || req_mem == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (content_type != NULL
&& BIO_printf(rctx->mem, "Content-Type: %s\r\n", content_type) <= 0)
return 0;
if ((req_len = BIO_get_mem_data(req_mem, &req)) <= 0)
return 0;
rctx->state = OHS_WRITE_INIT;
return BIO_printf(rctx->mem, "Content-Length: %ld\r\n\r\n", req_len) > 0
&& BIO_write(rctx->mem, req, req_len) == (int)req_len;
}
BIO *HTTP_asn1_item2bio(const ASN1_ITEM *it, const ASN1_VALUE *val)
{
BIO *res;
if (it == NULL || val == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if ((res = BIO_new(BIO_s_mem())) == NULL)
return NULL;
if (ASN1_item_i2d_bio(it, res, val) <= 0) {
BIO_free(res);
res = NULL;
}
return res;
}
int OSSL_HTTP_REQ_CTX_i2d(OSSL_HTTP_REQ_CTX *rctx, const char *content_type,
const ASN1_ITEM *it, ASN1_VALUE *req)
{
BIO *mem;
int res;
if (rctx == NULL || it == NULL || req == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
res = (mem = HTTP_asn1_item2bio(it, req)) != NULL
&& OSSL_HTTP_REQ_CTX_content(rctx, content_type, mem);
BIO_free(mem);
return res;
}
static int OSSL_HTTP_REQ_CTX_add1_headers(OSSL_HTTP_REQ_CTX *rctx,
const STACK_OF(CONF_VALUE) *headers,
const char *host)
{
int i;
int add_host = 1;
CONF_VALUE *hdr;
for (i = 0; i < sk_CONF_VALUE_num(headers); i++) {
hdr = sk_CONF_VALUE_value(headers, i);
if (add_host && strcasecmp("host", hdr->name) == 0)
add_host = 0;
if (!OSSL_HTTP_REQ_CTX_add1_header(rctx, hdr->name, hdr->value))
return 0;
}
if (add_host && !OSSL_HTTP_REQ_CTX_add1_header(rctx, "Host", host))
return 0;
return 1;
}
/*-
* Create OSSL_HTTP_REQ_CTX structure using the values provided.
* If !use_http_proxy then the 'server' and 'port' parameters are ignored.
* If req_mem == NULL then use GET and ignore content_type, else POST.
*/
OSSL_HTTP_REQ_CTX *HTTP_REQ_CTX_new(BIO *wbio, BIO *rbio, int use_http_proxy,
const char *server, const char *port,
const char *path,
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_content_type,
int expect_asn1)
{
OSSL_HTTP_REQ_CTX *rctx;
if (use_http_proxy && (server == NULL || port == NULL)) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
/* remaining parameters are checked indirectly by the functions called */
if ((rctx = OSSL_HTTP_REQ_CTX_new(wbio, rbio, req_mem == NULL, maxline,
max_resp_len, timeout,
expected_content_type, expect_asn1))
== NULL)
return NULL;
if (OSSL_HTTP_REQ_CTX_header(rctx, use_http_proxy ? server : NULL,
port, path)
&& OSSL_HTTP_REQ_CTX_add1_headers(rctx, headers, server)
&& (req_mem == NULL
|| OSSL_HTTP_REQ_CTX_content(rctx, content_type, req_mem)))
return rctx;
OSSL_HTTP_REQ_CTX_free(rctx);
return NULL;
}
/*
* Parse first HTTP response line. This should be like this: "HTTP/1.0 200 OK".
* We need to obtain the numeric code and (optional) informational message.
*/
static int parse_http_line1(char *line)
{
int retcode;
char *code, *reason, *end;
/* Skip to first whitespace (past protocol info) */
for (code = line; *code != '\0' && !ossl_isspace(*code); code++)
continue;
if (*code == '\0') {
HTTPerr(0, HTTP_R_RESPONSE_PARSE_ERROR);
return 0;
}
/* Skip past whitespace to start of response code */
while (*code != '\0' && ossl_isspace(*code))
code++;
if (*code == '\0') {
HTTPerr(0, HTTP_R_RESPONSE_PARSE_ERROR);
return 0;
}
/* Find end of response code: first whitespace after start of code */
for (reason = code; *reason != '\0' && !ossl_isspace(*reason); reason++)
continue;
if (*reason == '\0') {
HTTPerr(0, HTTP_R_RESPONSE_PARSE_ERROR);
return 0;
}
/* Set end of response code and start of message */
*reason++ = '\0';
/* Attempt to parse numeric code */
retcode = strtoul(code, &end, 10);
if (*end != '\0')
return 0;
/* Skip over any leading whitespace in message */
while (*reason != '\0' && ossl_isspace(*reason))
reason++;
if (*reason != '\0') {
/*
* Finally zap any trailing whitespace in message (include CRLF)
*/
/* chop any trailing whitespace from reason */
/* We know reason has a non-whitespace character so this is OK */
for (end = reason + strlen(reason) - 1; ossl_isspace(*end); end--)
*end = '\0';
}
switch (retcode) {
case HTTP_STATUS_CODE_OK:
case HTTP_STATUS_CODE_MOVED_PERMANENTLY:
case HTTP_STATUS_CODE_FOUND:
return retcode;
default:
if (retcode < 400)
HTTPerr(0, HTTP_R_STATUS_CODE_UNSUPPORTED);
else
HTTPerr(0, HTTP_R_RECEIVED_ERROR);
if (*reason == '\0')
ERR_add_error_data(2, "Code=", code);
else
ERR_add_error_data(4, "Code=", code, ",Reason=", reason);
return 0;
}
}
static int check_set_resp_len(OSSL_HTTP_REQ_CTX *rctx, unsigned long len)
{
const char *tag = NULL;
unsigned long val = 0;
if (len > rctx->max_resp_len) {
HTTPerr(0, HTTP_R_MAX_RESP_LEN_EXCEEDED);
tag = ",max=";
val = rctx->max_resp_len;
}
if (rctx->resp_len != 0 && rctx->resp_len != len) {
HTTPerr(0, HTTP_R_INCONSISTENT_CONTENT_LENGTH);
tag = ",before=";
val = rctx->resp_len;
}
if (tag != NULL) {
char len_str[32];
char str[32];
BIO_snprintf(len_str, sizeof(len_str), "%lu", len);
BIO_snprintf(str, sizeof(str), "%lu", val);
ERR_add_error_data(4, "length=", len_str, tag, str);
return 0;
}
rctx->resp_len = len;
return 1;
}
/*
* Try exchanging request and response via HTTP on (non-)blocking BIO in rctx.
* Returns 1 on success, 0 on error or redirection, -1 on BIO_should_retry.
*/
int OSSL_HTTP_REQ_CTX_nbio(OSSL_HTTP_REQ_CTX *rctx)
{
int i;
long n, n_to_send = 0;
unsigned long resp_len;
const unsigned char *p;
char *key, *value, *line_end = NULL;
if (rctx == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
rctx->redirection_url = NULL;
next_io:
if ((rctx->state & OHS_NOREAD) == 0) {
n = BIO_read(rctx->rbio, rctx->iobuf, rctx->iobuflen);
if (n <= 0) {
if (BIO_should_retry(rctx->rbio))
return -1;
return 0;
}
/* Write data to memory BIO */
if (BIO_write(rctx->mem, rctx->iobuf, n) != n)
return 0;
}
switch (rctx->state) {
case OHS_HTTP_HEADER:
/* Last operation was adding headers: need a final \r\n */
if (BIO_write(rctx->mem, "\r\n", 2) != 2) {
rctx->state = OHS_ERROR;
return 0;
}
rctx->state = OHS_WRITE_INIT;
/* fall thru */
case OHS_WRITE_INIT:
n_to_send = BIO_get_mem_data(rctx->mem, NULL);
rctx->state = OHS_WRITE;
/* fall thru */
case OHS_WRITE:
n = BIO_get_mem_data(rctx->mem, &p);
i = BIO_write(rctx->wbio, p + (n - n_to_send), n_to_send);
if (i <= 0) {
if (BIO_should_retry(rctx->wbio))
return -1;
rctx->state = OHS_ERROR;
return 0;
}
n_to_send -= i;
if (n_to_send > 0)
goto next_io;
rctx->state = OHS_FLUSH;
(void)BIO_reset(rctx->mem);
/* fall thru */
case OHS_FLUSH:
i = BIO_flush(rctx->wbio);
if (i > 0) {
rctx->state = OHS_FIRSTLINE;
goto next_io;
}
if (BIO_should_retry(rctx->wbio))
return -1;
rctx->state = OHS_ERROR;
return 0;
case OHS_ERROR:
return 0;
case OHS_FIRSTLINE:
case OHS_HEADERS:
case OHS_REDIRECT:
/* Attempt to read a line in */
next_line:
/*
* Due to strange memory BIO behavior with BIO_gets we have to check
* there's a complete line in there before calling BIO_gets or we'll
* just get a partial read.
*/
n = BIO_get_mem_data(rctx->mem, &p);
if (n <= 0 || memchr(p, '\n', n) == 0) {
if (n >= rctx->iobuflen) {
rctx->state = OHS_ERROR;
return 0;
}
goto next_io;
}
n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen);
if (n <= 0) {
if (BIO_should_retry(rctx->mem))
goto next_io;
rctx->state = OHS_ERROR;
return 0;
}
/* Don't allow excessive lines */
if (n == rctx->iobuflen) {
HTTPerr(0, HTTP_R_RESPONSE_LINE_TOO_LONG);
rctx->state = OHS_ERROR;
return 0;
}
/* First line */
if (rctx->state == OHS_FIRSTLINE) {
switch (parse_http_line1((char *)rctx->iobuf)) {
case HTTP_STATUS_CODE_OK:
rctx->state = OHS_HEADERS;
goto next_line;
case HTTP_STATUS_CODE_MOVED_PERMANENTLY:
case HTTP_STATUS_CODE_FOUND: /* i.e., moved temporarily */
if (rctx->method_GET) {
rctx->state = OHS_REDIRECT;
goto next_line;
}
HTTPerr(0, HTTP_R_REDIRECTION_NOT_ENABLED);
/* redirection is not supported/recommended for POST */
/* fall through */
default:
rctx->state = OHS_ERROR;
return 0;
}
}
key = (char *)rctx->iobuf;
value = strchr(key, ':');
if (value != NULL) {
*(value++) = '\0';
while (ossl_isspace(*value))
value++;
line_end = strchr(value, '\r');
if (line_end == NULL)
line_end = strchr(value, '\n');
if (line_end != NULL)
*line_end = '\0';
}
if (value != NULL && line_end != NULL) {
if (rctx->state == OHS_REDIRECT
&& strcasecmp(key, "Location") == 0) {
rctx->redirection_url = value;
return 0;
}
if (rctx->expected_ct != NULL
&& strcasecmp(key, "Content-Type") == 0) {
if (strcasecmp(rctx->expected_ct, value) != 0) {
HTTPerr(0, HTTP_R_UNEXPECTED_CONTENT_TYPE);
ERR_add_error_data(4, "expected=", rctx->expected_ct,
",actual=", value);
return 0;
}
rctx->expected_ct = NULL; /* content-type has been found */
}
if (strcasecmp(key, "Content-Length") == 0) {
resp_len = strtoul(value, &line_end, 10);
if (line_end == value || *line_end != '\0') {
HTTPerr(0, HTTP_R_ERROR_PARSING_CONTENT_LENGTH);
ERR_add_error_data(2, "input=", value);
return 0;
}
if (!check_set_resp_len(rctx, resp_len))
return 0;
}
}
/* Look for blank line: end of headers */
for (p = rctx->iobuf; *p != '\0'; p++) {
if (*p != '\r' && *p != '\n')
break;
}
if (*p != '\0') /* not end of headers */
goto next_line;
if (rctx->expected_ct != NULL) {
HTTPerr(0, HTTP_R_MISSING_CONTENT_TYPE);
ERR_add_error_data(2, "expected=", rctx->expected_ct);
return 0;
}
if (rctx->state == OHS_REDIRECT) {
/* http status code indicated redirect but there was no Location */
HTTPerr(0, HTTP_R_MISSING_REDIRECT_LOCATION);
return 0;
}
if (!rctx->expect_asn1) {
rctx->state = OHS_CONTENT;
goto content;
}
rctx->state = OHS_ASN1_HEADER;
/* Fall thru */
case OHS_ASN1_HEADER:
/*
* Now reading ASN1 header: can read at least 2 bytes which is enough
* for ASN1 SEQUENCE header and either length field or at least the
* length of the length field.
*/
n = BIO_get_mem_data(rctx->mem, &p);
if (n < 2)
goto next_io;
/* Check it is an ASN1 SEQUENCE */
if (*p++ != (V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)) {
HTTPerr(0, HTTP_R_MISSING_ASN1_ENCODING);
return 0;
}
/* Check out length field */
if ((*p & 0x80) != 0) {
/*
* If MSB set on initial length octet we can now always read 6
* octets: make sure we have them.
*/
if (n < 6)
goto next_io;
n = *p & 0x7F;
/* Not NDEF or excessive length */
if (n == 0 || (n > 4)) {
HTTPerr(0, HTTP_R_ERROR_PARSING_ASN1_LENGTH);
return 0;
}
p++;
resp_len = 0;
for (i = 0; i < n; i++) {
resp_len <<= 8;
resp_len |= *p++;
}
resp_len += n + 2;
} else {
resp_len = *p + 2;
}
if (!check_set_resp_len(rctx, resp_len))
return 0;
content:
rctx->state = OHS_CONTENT;
/* Fall thru */
case OHS_CONTENT:
default:
n = BIO_get_mem_data(rctx->mem, NULL);
if (n < (long)rctx->resp_len /* may be 0 if no Content-Type or ASN.1 */)
goto next_io;
rctx->state = OHS_DONE;
return 1;
}
}
#ifndef OPENSSL_NO_SOCK
/* set up a new connection BIO, to HTTP server or to HTTP(S) proxy if given */
static BIO *HTTP_new_bio(const char *server /* optionally includes ":port" */,
const char *server_port /* explicit server port */,
const char *proxy /* optionally includes ":port" */)
{
const char *host = server, *host_end;
char host_name[100];
const char *port = server_port;
BIO *cbio;
if (!ossl_assert(server != NULL))
return NULL;
if (proxy != NULL) {
host = proxy;
port = NULL;
}
host_end = strchr(host, '/');
if (host_end != NULL) {
size_t host_len = host_end - host;
if (host_len < sizeof(host_name)) {
/* chop trailing string starting with '/' */
strncpy(host_name, host, host_len);
host_name[host_len] = '\0';
host = host_name;
}
}
cbio = BIO_new_connect(host /* optionally includes ":port" */);
if (cbio == NULL)
goto end;
if (port != NULL)
(void)BIO_set_conn_port(cbio, port);
end:
return cbio;
}
#endif /* OPENSSL_NO_SOCK */
static ASN1_VALUE *BIO_mem_d2i(BIO *mem, const ASN1_ITEM *it)
{
const unsigned char *p;
long len = BIO_get_mem_data(mem, &p);
ASN1_VALUE *resp = ASN1_item_d2i(NULL, &p, len, it);
if (resp == NULL)
HTTPerr(0, HTTP_R_RESPONSE_PARSE_ERROR);
return resp;
}
static BIO *OSSL_HTTP_REQ_CTX_transfer(OSSL_HTTP_REQ_CTX *rctx)
{
int sending = 1;
int rv;
if (rctx == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
for (;;) {
rv = OSSL_HTTP_REQ_CTX_nbio(rctx);
if (rv != -1)
break;
/* BIO_should_retry was true */
sending = 0;
/* will not actually wait if rctx->max_time == 0 */
if (BIO_wait(rctx->rbio, rctx->max_time, 100 /* milliseconds */) <= 0)
return NULL;
}
if (rv == 0) {
if (rctx->redirection_url == NULL) { /* an error occurred */
if (sending && (rctx->state & OHS_NOREAD) != 0)
HTTPerr(0, HTTP_R_ERROR_SENDING);
else
HTTPerr(0, HTTP_R_ERROR_RECEIVING);
}
return NULL;
}
if (!BIO_up_ref(rctx->mem))
return NULL;
return rctx->mem;
}
/* Exchange ASN.1-encoded request and response via HTTP on (non-)blocking BIO */
ASN1_VALUE *OSSL_HTTP_REQ_CTX_sendreq_d2i(OSSL_HTTP_REQ_CTX *rctx,
const ASN1_ITEM *it)
{
if (rctx == NULL || it == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
return BIO_mem_d2i(OSSL_HTTP_REQ_CTX_transfer(rctx), it);
}
static int update_timeout(int timeout, time_t start_time)
{
long elapsed_time;
if (timeout == 0)
return 0;
elapsed_time = (long)(time(NULL) - start_time); /* this might overflow */
return timeout <= elapsed_time ? -1 : timeout - elapsed_time;
}
/*-
* Exchange HTTP request and response with the given server.
* If req_mem == NULL then use GET and ignore content_type, else POST.
* The redirection_url output (freed by caller) parameter is used only for GET.
*
* Typically the bio and rbio parameters are NULL and a network BIO is created
* internally for connecting to the given server and port, optionally via a
* proxy and its port, and is then used for exchanging the request and response.
* If bio is given and rbio is NULL then this BIO is used instead.
* If both bio and rbio are given (which may be memory BIOs for instance)
* then no explicit connection is attempted,
* bio is used for writing the request, and rbio for reading the response.
*
* bio_update_fn is an optional BIO connect/disconnect callback function,
* which has the prototype
* BIO *(*OSSL_HTTP_bio_cb_t) (BIO *bio, void *arg, int conn, int detail);
* The callback may modify the HTTP BIO provided in the bio argument,
* whereby it may make use of any custom defined argument 'arg'.
* During connection establishment, just after BIO_do_connect_retry(),
* the callback function is invoked with the 'conn' argument being 1
* 'detail' indicating whether a HTTPS (i.e., TLS) connection is requested.
* On disconnect 'conn' is 0 and 'detail' indicates that no error occurred.
* For instance, on connect the funct may prepend a TLS BIO to implement HTTPS;
* after disconnect it may do some error diagnostics and/or specific cleanup.
* The function should return NULL to indicate failure.
* After disconnect the modified BIO will be deallocated using BIO_free_all().
*/
BIO *OSSL_HTTP_transfer(const char *server, const char *port, const char *path,
int use_ssl, const char *proxy, const char *no_proxy,
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)
{
time_t start_time = timeout > 0 ? time(NULL) : 0;
BIO *cbio; /* = bio if present, used as connection BIO if rbio is NULL */
OSSL_HTTP_REQ_CTX *rctx;
BIO *resp = NULL;
if (redirection_url != NULL)
*redirection_url = NULL; /* do this beforehand to prevent dbl free */
if (use_ssl && bio_update_fn == NULL) {
HTTPerr(0, HTTP_R_TLS_NOT_ENABLED);
return NULL;
}
if (rbio != NULL && (bio == NULL || bio_update_fn != NULL)) {
HTTPerr(0, ERR_R_PASSED_INVALID_ARGUMENT);
return NULL;
}
if (bio != NULL) {
cbio = bio;
} else {
#ifndef OPENSSL_NO_SOCK
if (server == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if (*port == '\0')
port = NULL;
if (port == NULL && strchr(server, ':') == NULL)
port = use_ssl ? OSSL_HTTPS_PORT : OSSL_HTTP_PORT;
proxy = http_adapt_proxy(proxy, no_proxy, server, use_ssl);
if ((cbio = HTTP_new_bio(server, port, proxy)) == NULL)
return NULL;
#else
HTTPerr(0, HTTP_R_SOCK_NOT_SUPPORTED);
return NULL;
#endif
}
/* remaining parameters are checked indirectly by the functions called */
(void)ERR_set_mark(); /* prepare removing any spurious libssl errors */
if (rbio == NULL && BIO_do_connect_retry(cbio, timeout, -1) <= 0)
goto end;
/* now timeout is guaranteed to be >= 0 */
/* callback can be used to wrap or prepend TLS session */
if (bio_update_fn != NULL) {
BIO *orig_bio = cbio;
cbio = (*bio_update_fn)(cbio, arg, 1 /* connect */, use_ssl);
if (cbio == NULL) {
cbio = orig_bio;
goto end;
}
}
rctx = HTTP_REQ_CTX_new(cbio, rbio != NULL ? rbio : cbio,
!use_ssl && proxy != NULL, server, port, path,
headers, content_type, req_mem, maxline,
max_resp_len, update_timeout(timeout, start_time),
expected_ct, expect_asn1);
if (rctx == NULL)
goto end;
resp = OSSL_HTTP_REQ_CTX_transfer(rctx);
if (resp == NULL) {
if (rctx->redirection_url != NULL) {
if (redirection_url == NULL)
HTTPerr(0, HTTP_R_REDIRECTION_NOT_ENABLED);
else
/* may be NULL if out of memory: */
*redirection_url = OPENSSL_strdup(rctx->redirection_url);
} else {
char buf[200];
unsigned long err = ERR_peek_error();
int lib = ERR_GET_LIB(err);
int reason = ERR_GET_REASON(err);
if (lib == ERR_LIB_SSL || lib == ERR_LIB_HTTP
|| (lib == ERR_LIB_BIO && reason == BIO_R_CONNECT_TIMEOUT)
|| (lib == ERR_LIB_BIO && reason == BIO_R_CONNECT_ERROR)
#ifndef OPENSSL_NO_CMP
|| (lib == ERR_LIB_CMP
&& reason == CMP_R_POTENTIALLY_INVALID_CERTIFICATE)
#endif
) {
BIO_snprintf(buf, 200, "server=%s:%s", server, port);
ERR_add_error_data(1, buf);
if (proxy != NULL)
ERR_add_error_data(2, " proxy=", proxy);
if (err == 0) {
BIO_snprintf(buf, 200, " peer has disconnected%s",
use_ssl ? " violating the protocol" :
", likely because it requires the use of TLS");
ERR_add_error_data(1, buf);
}
}
}
}
OSSL_HTTP_REQ_CTX_free(rctx);
/* callback can be used to clean up TLS session */
if (bio_update_fn != NULL
&& (*bio_update_fn)(cbio, arg, 0, resp != NULL) == NULL) {
BIO_free(resp);
resp = NULL;
}
end:
/*
* Use BIO_free_all() because bio_update_fn may prepend or append to cbio.
* This also frees any (e.g., SSL/TLS) BIOs linked with bio and,
* like BIO_reset(bio), calls SSL_shutdown() to notify/alert the peer.
*/
if (bio == NULL) /* cbio was not provided by caller */
BIO_free_all(cbio);
if (resp != NULL)
/* remove any spurious error queue entries by ssl_add_cert_chain() */
(void)ERR_pop_to_mark();
else
(void)ERR_clear_last_mark();
return resp;
}
static int redirection_ok(int n_redir, const char *old_url, const char *new_url)
{
size_t https_len = strlen(OSSL_HTTPS_NAME":");
if (n_redir >= HTTP_VERSION_MAX_REDIRECTIONS) {
HTTPerr(0, HTTP_R_TOO_MANY_REDIRECTIONS);
return 0;
}
if (*new_url == '/') /* redirection to same server => same protocol */
return 1;
if (strncmp(old_url, OSSL_HTTPS_NAME":", https_len) == 0 &&
strncmp(new_url, OSSL_HTTPS_NAME":", https_len) != 0) {
HTTPerr(0, HTTP_R_REDIRECTION_FROM_HTTPS_TO_HTTP);
return 0;
}
return 1;
}
/* Get data via HTTP from server at given URL, potentially with redirection */
BIO *OSSL_HTTP_get(const char *url, const char *proxy, const char *no_proxy,
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)
{
time_t start_time = timeout > 0 ? time(NULL) : 0;
char *current_url, *redirection_url;
int n_redirs = 0;
char *host;
char *port;
char *path;
int use_ssl;
BIO *resp = NULL;
if (url == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if ((current_url = OPENSSL_strdup(url)) == NULL)
return NULL;
for (;;) {
if (!OSSL_HTTP_parse_url(current_url, &host, &port, NULL /* port_num */,
&path, &use_ssl))
break;
new_rpath:
resp = OSSL_HTTP_transfer(host, port, path, use_ssl, proxy, no_proxy,
bio, rbio,
bio_update_fn, arg, headers, NULL, NULL,
maxline, max_resp_len,
update_timeout(timeout, start_time),
expected_content_type, expect_asn1,
&redirection_url);
OPENSSL_free(path);
if (resp == NULL && redirection_url != NULL) {
if (redirection_ok(++n_redirs, current_url, redirection_url)) {
(void)BIO_reset(bio);
OPENSSL_free(current_url);
current_url = redirection_url;
if (*redirection_url == '/') { /* redirection to same server */
path = OPENSSL_strdup(redirection_url);
goto new_rpath;
}
OPENSSL_free(host);
OPENSSL_free(port);
continue;
}
OPENSSL_free(redirection_url);
}
OPENSSL_free(host);
OPENSSL_free(port);
break;
}
OPENSSL_free(current_url);
return resp;
}
/* Get ASN.1-encoded data via HTTP from server at given URL */
ASN1_VALUE *OSSL_HTTP_get_asn1(const char *url,
const char *proxy, const char *no_proxy,
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)
{
BIO *mem;
ASN1_VALUE *resp = NULL;
if (url == NULL || it == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if ((mem = OSSL_HTTP_get(url, proxy, no_proxy, bio, rbio, bio_update_fn,
arg, headers, maxline, max_resp_len, timeout,
expected_content_type, 1 /* expect_asn1 */))
!= NULL)
resp = BIO_mem_d2i(mem, it);
BIO_free(mem);
return resp;
}
/* Post ASN.1-encoded request via HTTP to server return ASN.1 response */
ASN1_VALUE *OSSL_HTTP_post_asn1(const char *server, const char *port,
const char *path, int use_ssl,
const char *proxy, const char *no_proxy,
BIO *bio, BIO *rbio,
OSSL_HTTP_bio_cb_t bio_update_fn, void *arg,
const STACK_OF(CONF_VALUE) *headers,
const char *content_type,
const 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 *req_mem;
BIO *res_mem;
ASN1_VALUE *resp = NULL;
if (req == NULL) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
/* remaining parameters are checked indirectly */
req_mem = HTTP_asn1_item2bio(req_it, req);
res_mem = OSSL_HTTP_transfer(server, port, path, use_ssl, proxy, no_proxy,
bio, rbio,
bio_update_fn, arg, headers, content_type,
req_mem /* may be NULL */, maxline,
max_resp_len, timeout,
expected_ct, 1 /* expect_asn1 */, NULL);
BIO_free(req_mem);
if (res_mem != NULL)
resp = BIO_mem_d2i(res_mem, rsp_it);
BIO_free(res_mem);
return resp;
}
/* BASE64 encoder used for encoding basic proxy authentication credentials */
static char *base64encode(const void *buf, size_t len)
{
int i;
size_t outl;
char *out;
/* Calculate size of encoded data */
outl = (len / 3);
if (len % 3 > 0)
outl++;
outl <<= 2;
out = OPENSSL_malloc(outl + 1);
if (out == NULL)
return 0;
i = EVP_EncodeBlock((unsigned char *)out, buf, len);
if (!ossl_assert(0 <= i && (size_t)i <= outl)) {
OPENSSL_free(out);
return NULL;
}
return out;
}
/*
* Promote the given connection BIO using the CONNECT method for a TLS proxy.
* This is typically called by an app, so bio_err and prog are used unless NULL
* to print additional diagnostic information in a user-oriented way.
*/
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)
{
#undef BUF_SIZE
#define BUF_SIZE (8 * 1024)
char *mbuf = OPENSSL_malloc(BUF_SIZE);
char *mbufp;
int read_len = 0;
int ret = 0;
BIO *fbio = BIO_new(BIO_f_buffer());
int rv;
time_t max_time = timeout > 0 ? time(NULL) + timeout : 0;
if (bio == NULL || server == NULL
|| (bio_err != NULL && prog == NULL)) {
HTTPerr(0, ERR_R_PASSED_NULL_PARAMETER);
goto end;
}
if (port == NULL || *port == '\0')
port = OSSL_HTTPS_PORT;
if (mbuf == NULL || fbio == NULL) {
BIO_printf(bio_err /* may be NULL */, "%s: out of memory", prog);
goto end;
}
BIO_push(fbio, bio);
BIO_printf(fbio, "CONNECT %s:%s "HTTP_PREFIX"1.0\r\n", server, port);
/*
* Workaround for broken proxies which would otherwise close
* the connection when entering tunnel mode (e.g., Squid 2.6)
*/
BIO_printf(fbio, "Proxy-Connection: Keep-Alive\r\n");
/* Support for basic (base64) proxy authentication */
if (proxyuser != NULL) {
size_t len = strlen(proxyuser) + 1;
char *proxyauth, *proxyauthenc = NULL;
if (proxypass != NULL)
len += strlen(proxypass);
proxyauth = OPENSSL_malloc(len + 1);
if (proxyauth == NULL)
goto end;
if (BIO_snprintf(proxyauth, len + 1, "%s:%s", proxyuser,
proxypass != NULL ? proxypass : "") != (int)len)
goto proxy_end;
proxyauthenc = base64encode(proxyauth, len);
if (proxyauthenc != NULL) {
BIO_printf(fbio, "Proxy-Authorization: Basic %s\r\n", proxyauthenc);
OPENSSL_clear_free(proxyauthenc, strlen(proxyauthenc));
}
proxy_end:
OPENSSL_clear_free(proxyauth, len);
if (proxyauthenc == NULL)
goto end;
}
/* Terminate the HTTP CONNECT request */
BIO_printf(fbio, "\r\n");
for (;;) {
if (BIO_flush(fbio) != 0)
break;
/* potentially needs to be retried if BIO is non-blocking */
if (!BIO_should_retry(fbio))
break;
}
for (;;) {
/* will not actually wait if timeout == 0 */
rv = BIO_wait(fbio, max_time, 100 /* milliseconds */);
if (rv <= 0) {
BIO_printf(bio_err, "%s: HTTP CONNECT %s\n", prog,
rv == 0 ? "timed out" : "failed waiting for data");
goto end;
}
/*-
* The first line is the HTTP response.
* According to RFC 7230, it is formatted exactly like this:
* HTTP/d.d ddd Reason text\r\n
*/
read_len = BIO_gets(fbio, mbuf, BUF_SIZE);
/* the BIO may not block, so we must wait for the 1st line to come in */
if (read_len < HTTP_LINE1_MINLEN)
continue;
/* RFC 7231 4.3.6: any 2xx status code is valid */
if (strncmp(mbuf, HTTP_PREFIX, strlen(HTTP_PREFIX)) != 0) {
HTTPerr(0, HTTP_R_RESPONSE_PARSE_ERROR);
BIO_printf(bio_err, "%s: HTTP CONNECT failed, non-HTTP response\n",
prog);
/* Wrong protocol, not even HTTP, so stop reading headers */
goto end;
}
mbufp = mbuf + strlen(HTTP_PREFIX);
if (strncmp(mbufp, HTTP_VERSION_PATT, strlen(HTTP_VERSION_PATT)) != 0) {
HTTPerr(0, HTTP_R_RECEIVED_WRONG_HTTP_VERSION);
BIO_printf(bio_err,
"%s: HTTP CONNECT failed, bad HTTP version %.*s\n",
prog, HTTP_VERSION_STR_LEN, mbufp);
goto end;
}
mbufp += HTTP_VERSION_STR_LEN;
if (strncmp(mbufp, " 2", strlen(" 2")) != 0) {
mbufp += 1;
/* chop any trailing whitespace */
while (read_len > 0 && ossl_isspace(mbuf[read_len - 1]))
read_len--;
mbuf[read_len] = '\0';
HTTPerr(0, HTTP_R_CONNECT_FAILURE);
ERR_add_error_data(2, "Reason=", mbufp);
BIO_printf(bio_err, "%s: HTTP CONNECT failed, Reason=%s\n",
prog, mbufp);
goto end;
}
ret = 1;
break;
}
/* Read past all following headers */
do {
/*
* TODO: This does not necessarily catch the case when the full
* HTTP response came in in more than a single TCP message.
*/
read_len = BIO_gets(fbio, mbuf, BUF_SIZE);
} while (read_len > 2);
end:
if (fbio != NULL) {
(void)BIO_flush(fbio);
BIO_pop(fbio);
BIO_free(fbio);
}
OPENSSL_free(mbuf);
return ret;
#undef BUF_SIZE
}
