386 lines
10 KiB
C
386 lines
10 KiB
C
/*
|
|
This file is part of TALER
|
|
Copyright (C) 2014-2020 Taler Systems SA
|
|
|
|
TALER is free software; you can redistribute it and/or modify it under the
|
|
terms of the GNU General Public License as published by the Free Software
|
|
Foundation; either version 3, or (at your option) any later version.
|
|
|
|
TALER is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
|
|
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License along with
|
|
TALER; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
|
|
*/
|
|
/**
|
|
* @file url.c
|
|
* @brief URL handling utility functions
|
|
* @author Florian Dold
|
|
*/
|
|
#include "platform.h"
|
|
#include "taler_util.h"
|
|
|
|
|
|
/**
|
|
* Check if a character is reserved and should
|
|
* be urlencoded.
|
|
*
|
|
* @param c character to look at
|
|
* @return true if @a c needs to be urlencoded,
|
|
* false otherwise
|
|
*/
|
|
static bool
|
|
is_reserved (char c)
|
|
{
|
|
switch (c)
|
|
{
|
|
case '0': case '1': case '2': case '3': case '4':
|
|
case '5': case '6': case '7': case '8': case '9':
|
|
case 'a': case 'b': case 'c': case 'd': case 'e':
|
|
case 'f': case 'g': case 'h': case 'i': case 'j':
|
|
case 'k': case 'l': case 'm': case 'n': case 'o':
|
|
case 'p': case 'q': case 'r': case 's': case 't':
|
|
case 'u': case 'v': case 'w': case 'x': case 'y': case 'z':
|
|
case 'A': case 'B': case 'C': case 'D': case 'E':
|
|
case 'F': case 'G': case 'H': case 'I': case 'J':
|
|
case 'K': case 'L': case 'M': case 'N': case 'O':
|
|
case 'P': case 'Q': case 'R': case 'S': case 'T':
|
|
case 'U': case 'V': case 'W': case 'X': case 'Y': case 'Z':
|
|
case '-': case '.': case '_': case '~':
|
|
return false;
|
|
default:
|
|
break;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
/**
|
|
* Get the length of a string after it has been
|
|
* urlencoded.
|
|
*
|
|
* @param s the string
|
|
* @returns the size of the urlencoded @a s
|
|
*/
|
|
static size_t
|
|
urlencode_len (const char *s)
|
|
{
|
|
size_t len = 0;
|
|
for (; *s != '\0'; len++, s++)
|
|
if (is_reserved (*s))
|
|
len += 2;
|
|
return len;
|
|
}
|
|
|
|
|
|
/**
|
|
* URL-encode a string according to rfc3986.
|
|
*
|
|
* @param buf buffer to write the result to
|
|
* @param s string to encode
|
|
*/
|
|
static void
|
|
buffer_write_urlencode (struct GNUNET_Buffer *buf,
|
|
const char *s)
|
|
{
|
|
size_t ulen;
|
|
|
|
ulen = urlencode_len (s);
|
|
GNUNET_assert (ulen < ulen + 1);
|
|
GNUNET_buffer_ensure_remaining (buf,
|
|
ulen + 1);
|
|
for (size_t i = 0; i < strlen (s); i++)
|
|
{
|
|
if (GNUNET_YES == is_reserved (s[i]))
|
|
GNUNET_buffer_write_fstr (buf,
|
|
"%%%02X",
|
|
s[i]);
|
|
else
|
|
buf->mem[buf->position++] = s[i];
|
|
}
|
|
}
|
|
|
|
|
|
/**
|
|
* URL-encode a string according to rfc3986.
|
|
*
|
|
* @param s string to encode
|
|
* @returns the urlencoded string, the caller must free it with #GNUNET_free()
|
|
*/
|
|
char *
|
|
TALER_urlencode (const char *s)
|
|
{
|
|
struct GNUNET_Buffer buf = { 0 };
|
|
|
|
buffer_write_urlencode (&buf,
|
|
s);
|
|
return GNUNET_buffer_reap_str (&buf);
|
|
}
|
|
|
|
|
|
/**
|
|
* Compute the total length of the @a args given. The args are a
|
|
* NULL-terminated list of key-value pairs, where the values
|
|
* must be URL-encoded. When serializing, the pairs will be separated
|
|
* via '?' or '&' and an '=' between key and value. Hence each
|
|
* pair takes an extra 2 characters to encode. This function computes
|
|
* how many bytes are needed. It must match the #serialize_arguments()
|
|
* function.
|
|
*
|
|
* @param args NULL-terminated key-value pairs (char *) for query parameters
|
|
* @return number of bytes needed (excluding 0-terminator) for the string buffer
|
|
*/
|
|
static size_t
|
|
calculate_argument_length (va_list args)
|
|
{
|
|
size_t len = 0;
|
|
va_list ap;
|
|
|
|
va_copy (ap,
|
|
args);
|
|
while (1)
|
|
{
|
|
char *key;
|
|
char *value;
|
|
size_t vlen;
|
|
size_t klen;
|
|
|
|
key = va_arg (ap,
|
|
char *);
|
|
if (NULL == key)
|
|
break;
|
|
value = va_arg (ap,
|
|
char *);
|
|
if (NULL == value)
|
|
continue;
|
|
vlen = urlencode_len (value);
|
|
klen = strlen (key);
|
|
GNUNET_assert ( (len <= len + vlen) &&
|
|
(len <= len + vlen + klen) &&
|
|
(len < len + vlen + klen + 2) );
|
|
len += vlen + klen + 2;
|
|
}
|
|
va_end (ap);
|
|
return len;
|
|
}
|
|
|
|
|
|
/**
|
|
* Take the key-value pairs in @a args and serialize them into
|
|
* @a buf, using URL encoding for the values. If a 'value' is
|
|
* given as NULL, both the key and the value are skipped. Note
|
|
* that a NULL value does not terminate the list, only a NULL
|
|
* key signals the end of the list of arguments.
|
|
*
|
|
* @param buf where to write the values
|
|
* @param args NULL-terminated key-value pairs (char *) for query parameters,
|
|
* the value will be url-encoded
|
|
*/
|
|
static void
|
|
serialize_arguments (struct GNUNET_Buffer *buf,
|
|
va_list args)
|
|
{
|
|
/* used to indicate if we are processing the initial
|
|
parameter which starts with '?' or subsequent
|
|
parameters which are separated with '&' */
|
|
unsigned int iparam = 0;
|
|
|
|
while (1)
|
|
{
|
|
char *key;
|
|
char *value;
|
|
|
|
key = va_arg (args,
|
|
char *);
|
|
if (NULL == key)
|
|
break;
|
|
value = va_arg (args,
|
|
char *);
|
|
if (NULL == value)
|
|
continue;
|
|
GNUNET_buffer_write_str (buf,
|
|
(0 == iparam) ? "?" : "&");
|
|
iparam = 1;
|
|
GNUNET_buffer_write_str (buf,
|
|
key);
|
|
GNUNET_buffer_write_str (buf,
|
|
"=");
|
|
buffer_write_urlencode (buf,
|
|
value);
|
|
}
|
|
}
|
|
|
|
|
|
/**
|
|
* Make an absolute URL with query parameters.
|
|
*
|
|
* If a 'value' is given as NULL, both the key and the value are skipped. Note
|
|
* that a NULL value does not terminate the list, only a NULL key signals the
|
|
* end of the list of arguments.
|
|
*
|
|
* @param base_url absolute base URL to use
|
|
* @param path path of the url
|
|
* @param ... NULL-terminated key-value pairs (char *) for query parameters,
|
|
* the value will be url-encoded
|
|
* @returns the URL (must be freed with #GNUNET_free) or
|
|
* NULL if an error occurred.
|
|
*/
|
|
char *
|
|
TALER_url_join (const char *base_url,
|
|
const char *path,
|
|
...)
|
|
{
|
|
struct GNUNET_Buffer buf = { 0 };
|
|
va_list args;
|
|
size_t len;
|
|
|
|
GNUNET_assert (NULL != base_url);
|
|
GNUNET_assert (NULL != path);
|
|
if (0 == strlen (base_url))
|
|
{
|
|
/* base URL can't be empty */
|
|
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
|
|
"Empty base URL specified\n");
|
|
return NULL;
|
|
}
|
|
if ('/' != base_url[strlen (base_url) - 1])
|
|
{
|
|
/* Must be an actual base URL! */
|
|
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
|
|
"Base URL `%s' does not end with '/', cannot join with `%s'\n",
|
|
base_url,
|
|
path);
|
|
return NULL;
|
|
}
|
|
if ('/' == path[0])
|
|
{
|
|
/* The path must be relative. */
|
|
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
|
|
"Path `%s' is not relative\n",
|
|
path);
|
|
return NULL;
|
|
}
|
|
|
|
va_start (args,
|
|
path);
|
|
|
|
len = strlen (base_url) + strlen (path) + 1;
|
|
len += calculate_argument_length (args);
|
|
|
|
GNUNET_buffer_prealloc (&buf,
|
|
len);
|
|
GNUNET_buffer_write_str (&buf,
|
|
base_url);
|
|
GNUNET_buffer_write_str (&buf,
|
|
path);
|
|
serialize_arguments (&buf,
|
|
args);
|
|
va_end (args);
|
|
|
|
return GNUNET_buffer_reap_str (&buf);
|
|
}
|
|
|
|
|
|
/**
|
|
* Make an absolute URL for the given parameters.
|
|
*
|
|
* If a 'value' is given as NULL, both the key and the value are skipped. Note
|
|
* that a NULL value does not terminate the list, only a NULL key signals the
|
|
* end of the list of arguments.
|
|
*
|
|
* @param proto protocol for the URL (typically https)
|
|
* @param host hostname for the URL
|
|
* @param prefix prefix for the URL
|
|
* @param path path for the URL
|
|
* @param args NULL-terminated key-value pairs (char *) for query parameters,
|
|
* the value will be url-encoded
|
|
* @returns the URL, must be freed with #GNUNET_free
|
|
*/
|
|
char *
|
|
TALER_url_absolute_raw_va (const char *proto,
|
|
const char *host,
|
|
const char *prefix,
|
|
const char *path,
|
|
va_list args)
|
|
{
|
|
struct GNUNET_Buffer buf = { 0 };
|
|
size_t len = 0;
|
|
|
|
len += strlen (proto) + strlen ("://") + strlen (host);
|
|
len += strlen (prefix) + strlen (path);
|
|
len += calculate_argument_length (args) + 1; /* 0-terminator */
|
|
|
|
GNUNET_buffer_prealloc (&buf,
|
|
len);
|
|
GNUNET_buffer_write_str (&buf,
|
|
proto);
|
|
GNUNET_buffer_write_str (&buf,
|
|
"://");
|
|
GNUNET_buffer_write_str (&buf,
|
|
host);
|
|
GNUNET_buffer_write_path (&buf,
|
|
prefix);
|
|
GNUNET_buffer_write_path (&buf,
|
|
path);
|
|
serialize_arguments (&buf,
|
|
args);
|
|
return GNUNET_buffer_reap_str (&buf);
|
|
}
|
|
|
|
|
|
/**
|
|
* Make an absolute URL for the given parameters.
|
|
*
|
|
* If a 'value' is given as NULL, both the key and the value are skipped. Note
|
|
* that a NULL value does not terminate the list, only a NULL key signals the
|
|
* end of the list of arguments.
|
|
*
|
|
* @param proto protocol for the URL (typically https)
|
|
* @param host hostname for the URL
|
|
* @param prefix prefix for the URL
|
|
* @param path path for the URL
|
|
* @param ... NULL-terminated key-value pairs (char *) for query parameters,
|
|
* the value will be url-encoded
|
|
* @return the URL, must be freed with #GNUNET_free
|
|
*/
|
|
char *
|
|
TALER_url_absolute_raw (const char *proto,
|
|
const char *host,
|
|
const char *prefix,
|
|
const char *path,
|
|
...)
|
|
{
|
|
char *result;
|
|
va_list args;
|
|
|
|
va_start (args,
|
|
path);
|
|
result = TALER_url_absolute_raw_va (proto,
|
|
host,
|
|
prefix,
|
|
path,
|
|
args);
|
|
va_end (args);
|
|
return result;
|
|
}
|
|
|
|
|
|
bool
|
|
TALER_url_valid_charset (const char *url)
|
|
{
|
|
for (unsigned int i = 0; '\0' != url[i]; i++)
|
|
{
|
|
#define ALLOWED_CHARACTERS \
|
|
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789/:;&?-.,=_~%"
|
|
if (NULL == strchr (ALLOWED_CHARACTERS,
|
|
(int) url[i]))
|
|
return false;
|
|
#undef ALLOWED_CHARACTERS
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
/* end of url.c */
|