/* stringprep.c --- Core stringprep implementation. * Copyright (C) 2002, 2003, 2004 Simon Josefsson * * This file is part of GNU Libidn. * * GNU Libidn is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * GNU Libidn 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with GNU Libidn; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA * */ #if HAVE_CONFIG_H # include "config.h" #endif #include <stdlib.h> #include <string.h> #include "stringprep.h" static ssize_t stringprep_find_character_in_table (uint32_t ucs4, const Stringprep_table_element * table) { ssize_t i; /* This is where typical uses of Libidn spends very close to all CPU time and causes most cache misses. One could easily do a binary search instead. Before rewriting this, I want hard evidence this slowness is at all relevant in typical applications. (I don't dispute optimization may improve matters significantly, I'm mostly interested in having someone give real-world benchmark on the impact of libidn.) */ for (i = 0; table[i].start || table[i].end; i++) if (ucs4 >= table[i].start && ucs4 <= (table[i].end ? table[i].end : table[i].start)) return i; return -1; } static ssize_t stringprep_find_string_in_table (uint32_t * ucs4, size_t ucs4len, size_t * tablepos, const Stringprep_table_element * table) { size_t j; ssize_t pos; for (j = 0; j < ucs4len; j++) if ((pos = stringprep_find_character_in_table (ucs4[j], table)) != -1) { if (tablepos) *tablepos = pos; return j; } return -1; } static int stringprep_apply_table_to_string (uint32_t * ucs4, size_t * ucs4len, size_t maxucs4len, const Stringprep_table_element * table) { ssize_t pos; size_t i, maplen; while ((pos = stringprep_find_string_in_table (ucs4, *ucs4len, &i, table)) != -1) { for (maplen = STRINGPREP_MAX_MAP_CHARS; maplen > 0 && table[i].map[maplen - 1] == 0; maplen--) ; if (*ucs4len - 1 + maplen >= maxucs4len) return STRINGPREP_TOO_SMALL_BUFFER; memmove (&ucs4[pos + maplen], &ucs4[pos + 1], sizeof (uint32_t) * (*ucs4len - pos - 1)); memcpy (&ucs4[pos], table[i].map, sizeof (uint32_t) * maplen); *ucs4len = *ucs4len - 1 + maplen; } return STRINGPREP_OK; } #define INVERTED(x) ((x) & ((~0UL) >> 1)) #define UNAPPLICAPLEFLAGS(flags, profileflags) \ ((!INVERTED(profileflags) && !(profileflags & flags) && profileflags) || \ ( INVERTED(profileflags) && (profileflags & flags))) /** * stringprep_4i - prepare internationalized string * @ucs4: input/output array with string to prepare. * @len: on input, length of input array with Unicode code points, * on exit, length of output array with Unicode code points. * @maxucs4len: maximum length of input/output array. * @flags: a #Stringprep_profile_flags value, or 0. * @profile: pointer to #Stringprep_profile to use. * * Prepare the input UCS-4 string according to the stringprep profile, * and write back the result to the input string. * * The input is not required to be zero terminated (@ucs4[@len] = 0). * The output will not be zero terminated unless @ucs4[@len] = 0. * Instead, see stringprep_4zi() if your input is zero terminated or * if you want the output to be. * * Since the stringprep operation can expand the string, @maxucs4len * indicate how large the buffer holding the string is. This function * will not read or write to code points outside that size. * * The @flags are one of #Stringprep_profile_flags values, or 0. * * The @profile contain the #Stringprep_profile instructions to * perform. Your application can define new profiles, possibly * re-using the generic stringprep tables that always will be part of * the library, or use one of the currently supported profiles. * * Return value: Returns %STRINGPREP_OK iff successful, or an * #Stringprep_rc error code. **/ int stringprep_4i (uint32_t * ucs4, size_t * len, size_t maxucs4len, Stringprep_profile_flags flags, const Stringprep_profile * profile) { size_t i, j; ssize_t k; size_t ucs4len = *len; int rc; for (i = 0; profile[i].operation; i++) { switch (profile[i].operation) { case STRINGPREP_NFKC: { uint32_t *q = 0; if (UNAPPLICAPLEFLAGS (flags, profile[i].flags)) break; if (flags & STRINGPREP_NO_NFKC && !profile[i].flags) /* Profile requires NFKC, but callee asked for no NFKC. */ return STRINGPREP_FLAG_ERROR; q = stringprep_ucs4_nfkc_normalize (ucs4, ucs4len); if (!q) return STRINGPREP_NFKC_FAILED; for (ucs4len = 0; q[ucs4len]; ucs4len++) ; if (ucs4len >= maxucs4len) { free (q); return STRINGPREP_TOO_SMALL_BUFFER; } memcpy (ucs4, q, ucs4len * sizeof (ucs4[0])); free (q); } break; case STRINGPREP_PROHIBIT_TABLE: k = stringprep_find_string_in_table (ucs4, ucs4len, NULL, profile[i].table); if (k != -1) return STRINGPREP_CONTAINS_PROHIBITED; break; case STRINGPREP_UNASSIGNED_TABLE: if (UNAPPLICAPLEFLAGS (flags, profile[i].flags)) break; if (flags & STRINGPREP_NO_UNASSIGNED) { k = stringprep_find_string_in_table (ucs4, ucs4len, NULL, profile[i].table); if (k != -1) return STRINGPREP_CONTAINS_UNASSIGNED; } break; case STRINGPREP_MAP_TABLE: if (UNAPPLICAPLEFLAGS (flags, profile[i].flags)) break; rc = stringprep_apply_table_to_string (ucs4, &ucs4len, maxucs4len, profile[i].table); if (rc != STRINGPREP_OK) return rc; break; case STRINGPREP_BIDI_PROHIBIT_TABLE: case STRINGPREP_BIDI_RAL_TABLE: case STRINGPREP_BIDI_L_TABLE: break; case STRINGPREP_BIDI: { int done_prohibited = 0; int done_ral = 0; int done_l = 0; int contains_ral = -1; int contains_l = -1; for (j = 0; profile[j].operation; j++) if (profile[j].operation == STRINGPREP_BIDI_PROHIBIT_TABLE) { done_prohibited = 1; k = stringprep_find_string_in_table (ucs4, ucs4len, NULL, profile[j].table); if (k != -1) return STRINGPREP_BIDI_CONTAINS_PROHIBITED; } else if (profile[j].operation == STRINGPREP_BIDI_RAL_TABLE) { done_ral = 1; if (stringprep_find_string_in_table (ucs4, ucs4len, NULL, profile[j].table) != -1) contains_ral = j; } else if (profile[j].operation == STRINGPREP_BIDI_L_TABLE) { done_l = 1; if (stringprep_find_string_in_table (ucs4, ucs4len, NULL, profile[j].table) != -1) contains_l = j; } if (!done_prohibited || !done_ral || !done_l) return STRINGPREP_PROFILE_ERROR; if (contains_ral != -1 && contains_l != -1) return STRINGPREP_BIDI_BOTH_L_AND_RAL; if (contains_ral != -1) { if (!(stringprep_find_character_in_table (ucs4[0], profile[contains_ral].table) != -1 && stringprep_find_character_in_table (ucs4[ucs4len - 1], profile[contains_ral].table) != -1)) return STRINGPREP_BIDI_LEADTRAIL_NOT_RAL; } } break; default: return STRINGPREP_PROFILE_ERROR; break; } } *len = ucs4len; return STRINGPREP_OK; } static int stringprep_4zi_1 (uint32_t * ucs4, size_t ucs4len, size_t maxucs4len, Stringprep_profile_flags flags, const Stringprep_profile * profile) { int rc; rc = stringprep_4i (ucs4, &ucs4len, maxucs4len, flags, profile); if (rc != STRINGPREP_OK) return rc; if (ucs4len >= maxucs4len) return STRINGPREP_TOO_SMALL_BUFFER; ucs4[ucs4len] = 0; return STRINGPREP_OK; } /** * stringprep_4zi - prepare internationalized string * @ucs4: input/output array with zero terminated string to prepare. * @maxucs4len: maximum length of input/output array. * @flags: a #Stringprep_profile_flags value, or 0. * @profile: pointer to #Stringprep_profile to use. * * Prepare the input zero terminated UCS-4 string according to the * stringprep profile, and write back the result to the input string. * * Since the stringprep operation can expand the string, @maxucs4len * indicate how large the buffer holding the string is. This function * will not read or write to code points outside that size. * * The @flags are one of #Stringprep_profile_flags values, or 0. * * The @profile contain the #Stringprep_profile instructions to * perform. Your application can define new profiles, possibly * re-using the generic stringprep tables that always will be part of * the library, or use one of the currently supported profiles. * * Return value: Returns %STRINGPREP_OK iff successful, or an * #Stringprep_rc error code. **/ int stringprep_4zi (uint32_t * ucs4, size_t maxucs4len, Stringprep_profile_flags flags, const Stringprep_profile * profile) { size_t ucs4len; for (ucs4len = 0; ucs4len < maxucs4len && ucs4[ucs4len] != 0; ucs4len++) ; return stringprep_4zi_1 (ucs4, ucs4len, maxucs4len, flags, profile); } /** * stringprep - prepare internationalized string * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * @flags: a #Stringprep_profile_flags value, or 0. * @profile: pointer to #Stringprep_profile to use. * * Prepare the input zero terminated UTF-8 string according to the * stringprep profile, and write back the result to the input string. * * Note that you must convert strings entered in the systems locale * into UTF-8 before using this function, see * stringprep_locale_to_utf8(). * * Since the stringprep operation can expand the string, @maxlen * indicate how large the buffer holding the string is. This function * will not read or write to characters outside that size. * * The @flags are one of #Stringprep_profile_flags values, or 0. * * The @profile contain the #Stringprep_profile instructions to * perform. Your application can define new profiles, possibly * re-using the generic stringprep tables that always will be part of * the library, or use one of the currently supported profiles. * * Return value: Returns %STRINGPREP_OK iff successful, or an error code. **/ int stringprep (char *in, size_t maxlen, Stringprep_profile_flags flags, const Stringprep_profile * profile) { int rc; char *utf8 = NULL; uint32_t *ucs4 = NULL; size_t ucs4len, maxucs4len, adducs4len = 50; do { uint32_t *newp; if (ucs4) free (ucs4); ucs4 = stringprep_utf8_to_ucs4 (in, -1, &ucs4len); maxucs4len = ucs4len + adducs4len; newp = realloc (ucs4, maxucs4len * sizeof (uint32_t)); if (!newp) { free (ucs4); return STRINGPREP_MALLOC_ERROR; } ucs4 = newp; rc = stringprep_4i (ucs4, &ucs4len, maxucs4len, flags, profile); adducs4len += 50; } while (rc == STRINGPREP_TOO_SMALL_BUFFER); if (rc != STRINGPREP_OK) { free (ucs4); return rc; } utf8 = stringprep_ucs4_to_utf8 (ucs4, ucs4len, 0, 0); free (ucs4); if (!utf8) return STRINGPREP_MALLOC_ERROR; if (strlen (utf8) >= maxlen) { free (utf8); return STRINGPREP_TOO_SMALL_BUFFER; } strcpy (in, utf8); /* flawfinder: ignore */ free (utf8); return STRINGPREP_OK; } /** * stringprep_profile - prepare internationalized string * @in: input array with UTF-8 string to prepare. * @out: output variable with pointer to newly allocate string. * @profile: name of stringprep profile to use. * @flags: a #Stringprep_profile_flags value, or 0. * * Prepare the input zero terminated UTF-8 string according to the * stringprep profile, and return the result in a newly allocated * variable. * * Note that you must convert strings entered in the systems locale * into UTF-8 before using this function, see * stringprep_locale_to_utf8(). * * The output @out variable must be deallocated by the caller. * * The @flags are one of #Stringprep_profile_flags values, or 0. * * The @profile specifies the name of the stringprep profile to use. * It must be one of the internally supported stringprep profiles. * * Return value: Returns %STRINGPREP_OK iff successful, or an error code. **/ int stringprep_profile (const char *in, char **out, const char *profile, Stringprep_profile_flags flags) { const Stringprep_profiles *p; char *str = NULL; size_t len = strlen (in) + 1; int rc; for (p = &stringprep_profiles[0]; p->name; p++) if (strcmp (p->name, profile) == 0) break; if (!p || !p->name || !p->tables) return STRINGPREP_UNKNOWN_PROFILE; do { if (str) free (str); str = (char *) malloc (len); if (str == NULL) return STRINGPREP_MALLOC_ERROR; strcpy (str, in); rc = stringprep (str, len, flags, p->tables); len += 50; } while (rc == STRINGPREP_TOO_SMALL_BUFFER); if (rc == STRINGPREP_OK) *out = str; else free (str); return rc; } /*! \mainpage GNU Internationalized Domain Name Library * * \section intro Introduction * * GNU Libidn is an implementation of the Stringprep, Punycode and IDNA * specifications defined by the IETF Internationalized Domain Names * (IDN) working group, used for internationalized domain names. The * package is available under the GNU Lesser General Public License. * * The library contains a generic Stringprep implementation that does * Unicode 3.2 NFKC normalization, mapping and prohibitation of * characters, and bidirectional character handling. Profiles for * Nameprep, iSCSI, SASL and XMPP are included. Punycode and ASCII * Compatible Encoding (ACE) via IDNA are supported. A mechanism to * define Top-Level Domain (TLD) specific validation tables, and to * compare strings against those tables, is included. Default tables * for some TLDs are also included. * * The Stringprep API consists of two main functions, one for * converting data from the system's native representation into UTF-8, * and one function to perform the Stringprep processing. Adding a * new Stringprep profile for your application within the API is * straightforward. The Punycode API consists of one encoding * function and one decoding function. The IDNA API consists of the * ToASCII and ToUnicode functions, as well as an high-level interface * for converting entire domain names to and from the ACE encoded * form. The TLD API consists of one set of functions to extract the * TLD name from a domain string, one set of functions to locate the * proper TLD table to use based on the TLD name, and core functions * to validate a string against a TLD table, and some utility wrappers * to perform all the steps in one call. * * The library is used by, e.g., GNU SASL and Shishi to process user * names and passwords. Libidn can be built into GNU Libc to enable a * new system-wide getaddrinfo() flag for IDN processing. * * Libidn is developed for the GNU/Linux system, but runs on over 20 Unix * platforms (including Solaris, IRIX, AIX, and Tru64) and Windows. * Libidn is written in C and (parts of) the API is accessible from C, * C++, Emacs Lisp, Python and Java. * * The project web page:\n * http://www.gnu.org/software/libidn/ * * The software archive:\n * ftp://alpha.gnu.org/pub/gnu/libidn/ * * For more information see:\n * http://www.ietf.org/html.charters/idn-charter.html\n * http://www.ietf.org/rfc/rfc3454.txt (stringprep specification)\n * http://www.ietf.org/rfc/rfc3490.txt (idna specification)\n * http://www.ietf.org/rfc/rfc3491.txt (nameprep specification)\n * http://www.ietf.org/rfc/rfc3492.txt (punycode specification)\n * http://www.ietf.org/internet-drafts/draft-ietf-ips-iscsi-string-prep-04.txt\n * http://www.ietf.org/internet-drafts/draft-ietf-krb-wg-utf8-profile-01.txt\n * http://www.ietf.org/internet-drafts/draft-ietf-sasl-anon-00.txt\n * http://www.ietf.org/internet-drafts/draft-ietf-sasl-saslprep-00.txt\n * http://www.ietf.org/internet-drafts/draft-ietf-xmpp-nodeprep-01.txt\n * http://www.ietf.org/internet-drafts/draft-ietf-xmpp-resourceprep-01.txt\n * * Further information and paid contract development:\n * Simon Josefsson <simon@josefsson.org> * * \section examples Examples * * \include example.c * \include example3.c * \include example4.c * \include example5.c */ /** * STRINGPREP_VERSION * * String defined via CPP denoting the header file version number. * Used together with stringprep_check_version() to verify header file * and run-time library consistency. */ /** * STRINGPREP_MAX_MAP_CHARS * * Maximum number of code points that can replace a single code point, * during stringprep mapping. */ /** * Stringprep_rc: * @STRINGPREP_OK: Successful operation. This value is guaranteed to * always be zero, the remaining ones are only guaranteed to hold * non-zero values, for logical comparison purposes. * @STRINGPREP_CONTAINS_UNASSIGNED: String contain unassigned Unicode * code points, which is forbidden by the profile. * @STRINGPREP_CONTAINS_PROHIBITED: String contain code points * prohibited by the profile. * @STRINGPREP_BIDI_BOTH_L_AND_RAL: String contain code points with * conflicting bidirection category. * @STRINGPREP_BIDI_LEADTRAIL_NOT_RAL: Leading and trailing character * in string not of proper bidirectional category. * @STRINGPREP_BIDI_CONTAINS_PROHIBITED: Contains prohibited code * points detected by bidirectional code. * @STRINGPREP_TOO_SMALL_BUFFER: Buffer handed to function was too * small. This usually indicate a problem in the calling * application. * @STRINGPREP_PROFILE_ERROR: The stringprep profile was inconsistent. * This usually indicate an internal error in the library. * @STRINGPREP_FLAG_ERROR: The supplied flag conflicted with profile. * This usually indicate a problem in the calling application. * @STRINGPREP_UNKNOWN_PROFILE: The supplied profile name was not * known to the library. * @STRINGPREP_NFKC_FAILED: The Unicode NFKC operation failed. This * usually indicate an internal error in the library. * @STRINGPREP_MALLOC_ERROR: The malloc() was out of memory. This is * usually a fatal error. * * Enumerated return codes of stringprep(), stringprep_profile() * functions (and macros using those functions). The value 0 is * guaranteed to always correspond to success. */ /** * Stringprep_profile_flags: * @STRINGPREP_NO_NFKC: Disable the NFKC normalization, as well as * selecting the non-NFKC case folding tables. Usually the profile * specifies BIDI and NFKC settings, and applications should not * override it unless in special situations. * @STRINGPREP_NO_BIDI: Disable the BIDI step. Usually the profile * specifies BIDI and NFKC settings, and applications should not * override it unless in special situations. * @STRINGPREP_NO_UNASSIGNED: Make the library return with an error if * string contains unassigned characters according to profile. * * Stringprep profile flags. */ /** * Stringprep_profile_steps: * * Various steps in the stringprep algorithm. You really want to * study the source code to understand this one. Only useful if you * want to add another profile. */ /** * stringprep_nameprep: * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * * Prepare the input UTF-8 string according to the nameprep profile. * The AllowUnassigned flag is true, use * stringprep_nameprep_no_unassigned() if you want a false * AllowUnassigned. Returns 0 iff successful, or an error code. **/ /** * stringprep_nameprep_no_unassigned: * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * * Prepare the input UTF-8 string according to the nameprep profile. * The AllowUnassigned flag is false, use stringprep_nameprep() for * true AllowUnassigned. Returns 0 iff successful, or an error code. **/ /** * stringprep_iscsi: * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * * Prepare the input UTF-8 string according to the draft iSCSI * stringprep profile. Returns 0 iff successful, or an error code. **/ /** * stringprep_plain: * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * * Prepare the input UTF-8 string according to the draft SASL * ANONYMOUS profile. Returns 0 iff successful, or an error code. **/ /** * stringprep_xmpp_nodeprep: * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * * Prepare the input UTF-8 string according to the draft XMPP node * identifier profile. Returns 0 iff successful, or an error code. **/ /** * stringprep_xmpp_resourceprep: * @in: input/ouput array with string to prepare. * @maxlen: maximum length of input/output array. * * Prepare the input UTF-8 string according to the draft XMPP resource * identifier profile. Returns 0 iff successful, or an error code. **/