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Diffstat (limited to 'Utilities/cmcurl/lib/escape.c')
| -rw-r--r-- | Utilities/cmcurl/lib/escape.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/Utilities/cmcurl/lib/escape.c b/Utilities/cmcurl/lib/escape.c new file mode 100644 index 0000000000..56aa2b3988 --- /dev/null +++ b/Utilities/cmcurl/lib/escape.c @@ -0,0 +1,235 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at https://curl.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + * SPDX-License-Identifier: curl + * + ***************************************************************************/ + +/* Escape and unescape URL encoding in strings. The functions return a new + * allocated string or NULL if an error occurred. */ + +#include "curl_setup.h" + +#include <curl/curl.h> + +#include "urldata.h" +#include "warnless.h" +#include "escape.h" +#include "strdup.h" +/* The last 3 #include files should be in this order */ +#include "curl_printf.h" +#include "curl_memory.h" +#include "memdebug.h" + +/* Portable character check (remember EBCDIC). Do not use isalnum() because + its behavior is altered by the current locale. + See https://datatracker.ietf.org/doc/html/rfc3986#section-2.3 +*/ +bool Curl_isunreserved(unsigned char in) +{ + switch(in) { + 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 TRUE; + default: + break; + } + return FALSE; +} + +/* for ABI-compatibility with previous versions */ +char *curl_escape(const char *string, int inlength) +{ + return curl_easy_escape(NULL, string, inlength); +} + +/* for ABI-compatibility with previous versions */ +char *curl_unescape(const char *string, int length) +{ + return curl_easy_unescape(NULL, string, length, NULL); +} + +/* Escapes for URL the given unescaped string of given length. + * 'data' is ignored since 7.82.0. + */ +char *curl_easy_escape(struct Curl_easy *data, const char *string, + int inlength) +{ + size_t length; + struct dynbuf d; + (void)data; + + if(inlength < 0) + return NULL; + + Curl_dyn_init(&d, CURL_MAX_INPUT_LENGTH * 3); + + length = (inlength?(size_t)inlength:strlen(string)); + if(!length) + return strdup(""); + + while(length--) { + unsigned char in = *string++; /* treat the characters unsigned */ + + if(Curl_isunreserved(in)) { + /* append this */ + if(Curl_dyn_addn(&d, &in, 1)) + return NULL; + } + else { + /* encode it */ + const char hex[] = "0123456789ABCDEF"; + char out[3]={'%'}; + out[1] = hex[in>>4]; + out[2] = hex[in & 0xf]; + if(Curl_dyn_addn(&d, out, 3)) + return NULL; + } + } + + return Curl_dyn_ptr(&d); +} + +static const unsigned char hextable[] = { + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 0, 0, 0, 0, 0, /* 0x30 - 0x3f */ + 0, 10, 11, 12, 13, 14, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x40 - 0x4f */ + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x50 - 0x5f */ + 0, 10, 11, 12, 13, 14, 15 /* 0x60 - 0x66 */ +}; + +/* the input is a single hex digit */ +#define onehex2dec(x) hextable[x - '0'] + +/* + * Curl_urldecode() URL decodes the given string. + * + * Returns a pointer to a malloced string in *ostring with length given in + * *olen. If length == 0, the length is assumed to be strlen(string). + * + * ctrl options: + * - REJECT_NADA: accept everything + * - REJECT_CTRL: rejects control characters (byte codes lower than 32) in + * the data + * - REJECT_ZERO: rejects decoded zero bytes + * + * The values for the enum starts at 2, to make the assert detect legacy + * invokes that used TRUE/FALSE (0 and 1). + */ + +CURLcode Curl_urldecode(const char *string, size_t length, + char **ostring, size_t *olen, + enum urlreject ctrl) +{ + size_t alloc; + char *ns; + + DEBUGASSERT(string); + DEBUGASSERT(ctrl >= REJECT_NADA); /* crash on TRUE/FALSE */ + + alloc = (length?length:strlen(string)); + ns = malloc(alloc + 1); + + if(!ns) + return CURLE_OUT_OF_MEMORY; + + /* store output string */ + *ostring = ns; + + while(alloc) { + unsigned char in = *string; + if(('%' == in) && (alloc > 2) && + ISXDIGIT(string[1]) && ISXDIGIT(string[2])) { + /* this is two hexadecimal digits following a '%' */ + in = (unsigned char)(onehex2dec(string[1]) << 4) | onehex2dec(string[2]); + + string += 3; + alloc -= 3; + } + else { + string++; + alloc--; + } + + if(((ctrl == REJECT_CTRL) && (in < 0x20)) || + ((ctrl == REJECT_ZERO) && (in == 0))) { + Curl_safefree(*ostring); + return CURLE_URL_MALFORMAT; + } + + *ns++ = in; + } + *ns = 0; /* terminate it */ + + if(olen) + /* store output size */ + *olen = ns - *ostring; + + return CURLE_OK; +} + +/* + * Unescapes the given URL escaped string of given length. Returns a + * pointer to a malloced string with length given in *olen. + * If length == 0, the length is assumed to be strlen(string). + * If olen == NULL, no output length is stored. + * 'data' is ignored since 7.82.0. + */ +char *curl_easy_unescape(struct Curl_easy *data, const char *string, + int length, int *olen) +{ + char *str = NULL; + (void)data; + if(length >= 0) { + size_t inputlen = (size_t)length; + size_t outputlen; + CURLcode res = Curl_urldecode(string, inputlen, &str, &outputlen, + REJECT_NADA); + if(res) + return NULL; + + if(olen) { + if(outputlen <= (size_t) INT_MAX) + *olen = curlx_uztosi(outputlen); + else + /* too large to return in an int, fail! */ + Curl_safefree(str); + } + } + return str; +} + +/* For operating systems/environments that use different malloc/free + systems for the app and for this library, we provide a free that uses + the library's memory system */ +void curl_free(void *p) +{ + free(p); +} |