/* conversion.c - String conversion helper functions. Copyright (C) 2000 Werner Koch (dd9jn) Copyright (C) 2001, 2002, 2003, 2004, 2007 g10 Code GmbH This file is part of GPGME. GPGME 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. GPGME 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 this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #if HAVE_CONFIG_H #include #endif #include #include #ifdef HAVE_SYS_TYPES_H /* Solaris 8 needs sys/types.h before time.h. */ # include #endif #include #include #include "gpgme.h" #include "util.h" #include "debug.h" #define atoi_1(p) (*(p) - '0' ) #define atoi_2(p) ((atoi_1(p) * 10) + atoi_1((p)+1)) #define atoi_4(p) ((atoi_2(p) * 100) + atoi_2((p)+2)) /* Convert two hexadecimal digits from STR to the value they represent. Returns -1 if one of the characters is not a hexadecimal digit. */ int _gpgme_hextobyte (const char *str) { int val = 0; int i; #define NROFHEXDIGITS 2 for (i = 0; i < NROFHEXDIGITS; i++) { if (*str >= '0' && *str <= '9') val += *str - '0'; else if (*str >= 'A' && *str <= 'F') val += 10 + *str - 'A'; else if (*str >= 'a' && *str <= 'f') val += 10 + *str - 'a'; else return -1; if (i < NROFHEXDIGITS - 1) val *= 16; str++; } return val; } /* Decode the C formatted string SRC and store the result in the buffer *DESTP which is LEN bytes long. If LEN is zero, then a large enough buffer is allocated with malloc and *DESTP is set to the result. Currently, LEN is only used to specify if allocation is desired or not, the caller is expected to make sure that *DESTP is large enough if LEN is not zero. */ gpgme_error_t _gpgme_decode_c_string (const char *src, char **destp, size_t len) { char *dest; /* Set up the destination buffer. */ if (len) { if (len < strlen (src) + 1) return gpg_error (GPG_ERR_INTERNAL); dest = *destp; } else { /* The converted string will never be larger than the original string. */ dest = malloc (strlen (src) + 1); if (!dest) return gpg_error_from_syserror (); *destp = dest; } /* Convert the string. */ while (*src) { if (*src != '\\') { *(dest++) = *(src++); continue; } switch (src[1]) { #define DECODE_ONE(match,result) \ case match: \ src += 2; \ *(dest++) = result; \ break; DECODE_ONE ('\'', '\''); DECODE_ONE ('\"', '\"'); DECODE_ONE ('\?', '\?'); DECODE_ONE ('\\', '\\'); DECODE_ONE ('a', '\a'); DECODE_ONE ('b', '\b'); DECODE_ONE ('f', '\f'); DECODE_ONE ('n', '\n'); DECODE_ONE ('r', '\r'); DECODE_ONE ('t', '\t'); DECODE_ONE ('v', '\v'); case 'x': { int val = _gpgme_hextobyte (&src[2]); if (val == -1) { /* Should not happen. */ *(dest++) = *(src++); *(dest++) = *(src++); if (*src) *(dest++) = *(src++); if (*src) *(dest++) = *(src++); } else { if (!val) { /* A binary zero is not representable in a C string. */ *(dest++) = '\\'; *(dest++) = '0'; } else *((unsigned char *) dest++) = val; src += 4; } } break; default: { /* Should not happen. */ *(dest++) = *(src++); *(dest++) = *(src++); } } } *(dest++) = 0; return 0; } /* Decode the percent escaped string SRC and store the result in the buffer *DESTP which is LEN bytes long. If LEN is zero, then a large enough buffer is allocated with malloc and *DESTP is set to the result. Currently, LEN is only used to specify if allocation is desired or not, the caller is expected to make sure that *DESTP is large enough if LEN is not zero. If BINARY is 1, then '\0' characters are allowed in the output. */ gpgme_error_t _gpgme_decode_percent_string (const char *src, char **destp, size_t len, int binary) { char *dest; /* Set up the destination buffer. */ if (len) { if (len < strlen (src) + 1) return gpg_error (GPG_ERR_INTERNAL); dest = *destp; } else { /* The converted string will never be larger than the original string. */ dest = malloc (strlen (src) + 1); if (!dest) return gpg_error_from_syserror (); *destp = dest; } /* Convert the string. */ while (*src) { if (*src != '%') { *(dest++) = *(src++); continue; } else { int val = _gpgme_hextobyte (&src[1]); if (val == -1) { /* Should not happen. */ *(dest++) = *(src++); if (*src) *(dest++) = *(src++); if (*src) *(dest++) = *(src++); } else { if (!val && !binary) { /* A binary zero is not representable in a C string. */ *(dest++) = '\\'; *(dest++) = '0'; } else *((unsigned char *) dest++) = val; src += 3; } } } *(dest++) = 0; return 0; } /* Encode the string SRC with percent escaping and store the result in the buffer *DESTP which is LEN bytes long. If LEN is zero, then a large enough buffer is allocated with malloc and *DESTP is set to the result. Currently, LEN is only used to specify if allocation is desired or not, the caller is expected to make sure that *DESTP is large enough if LEN is not zero. If BINARY is 1, then '\0' characters are allowed in the output. */ gpgme_error_t _gpgme_encode_percent_string (const char *src, char **destp, size_t len) { size_t destlen; char *dest; const char *str; destlen = 0; str = src; /* We percent-escape the + character because the user might need a "percent plus" escaped string (special gpg format). But we percent-escape the space character, which works with and without the special plus format. */ while (*str) { if (*str == '+' || *str == '\"' || *str == '%' || *(const unsigned char *)str <= 0x20) destlen += 3; else destlen++; str++; } /* Terminating nul byte. */ destlen++; /* Set up the destination buffer. */ if (len) { if (len < destlen) return gpg_error (GPG_ERR_INTERNAL); dest = *destp; } else { /* The converted string will never be larger than the original string. */ dest = malloc (destlen); if (!dest) return gpg_error_from_syserror (); *destp = dest; } /* Convert the string. */ while (*src) { if (*src == '+' || *src == '\"' || *src == '%' || *(const unsigned char *)src <= 0x20) { snprintf (dest, 4, "%%%02X", *(unsigned char *)src); dest += 3; } else *(dest++) = *src; src++; } *(dest++) = 0; return 0; } #ifdef HAVE_W32_SYSTEM static time_t _gpgme_timegm (struct tm *tm) { /* This one is thread safe. */ SYSTEMTIME st; FILETIME ft; unsigned long long cnsecs; st.wYear = tm->tm_year + 1900; st.wMonth = tm->tm_mon + 1; st.wDay = tm->tm_mday; st.wHour = tm->tm_hour; st.wMinute = tm->tm_min; st.wSecond = tm->tm_sec; st.wMilliseconds = 0; /* Not available. */ st.wDayOfWeek = 0; /* Ignored. */ /* System time is UTC thus the conversion is pretty easy. */ if (!SystemTimeToFileTime (&st, &ft)) { gpg_err_set_errno (EINVAL); return (time_t)(-1); } cnsecs = (((unsigned long long)ft.dwHighDateTime << 32) | ft.dwLowDateTime); cnsecs -= 116444736000000000ULL; /* The filetime epoch is 1601-01-01. */ return (time_t)(cnsecs / 10000000ULL); } #endif /* Parse the string TIMESTAMP into a time_t. The string may either be seconds since Epoch or in the ISO 8601 format like "20390815T143012". Returns 0 for an empty string or seconds since Epoch. Leading spaces are skipped. If ENDP is not NULL, it will point to the next non-parsed character in TIMESTRING. */ time_t _gpgme_parse_timestamp (const char *timestamp, char **endp) { /* Need to skip leading spaces, because that is what strtoul does but not our ISO 8601 checking code. */ while (*timestamp && *timestamp== ' ') timestamp++; if (!*timestamp) return 0; if (strlen (timestamp) >= 15 && timestamp[8] == 'T') { struct tm buf; int year; year = atoi_4 (timestamp); if (year < 1900) return (time_t)(-1); if (endp) *endp = (char*)(timestamp + 15); /* Fixme: We would better use a configure test to see whether mktime can handle dates beyond 2038. */ if (sizeof (time_t) <= 4 && year >= 2038) return (time_t)2145914603; /* 2037-12-31 23:23:23 */ memset (&buf, 0, sizeof buf); buf.tm_year = year - 1900; buf.tm_mon = atoi_2 (timestamp+4) - 1; buf.tm_mday = atoi_2 (timestamp+6); buf.tm_hour = atoi_2 (timestamp+9); buf.tm_min = atoi_2 (timestamp+11); buf.tm_sec = atoi_2 (timestamp+13); #ifdef HAVE_W32_SYSTEM return _gpgme_timegm (&buf); #else #ifdef HAVE_TIMEGM return timegm (&buf); #else { time_t tim; putenv ("TZ=UTC"); tim = mktime (&buf); #ifdef __GNUC__ #warning fixme: we must somehow reset TZ here. It is not threadsafe anyway. #endif return tim; } #endif /* !HAVE_TIMEGM */ #endif /* !HAVE_W32_SYSTEM */ } else return (time_t)strtoul (timestamp, endp, 10); } /* The GPG backend uses OpenPGP algorithm numbers which we need to map to our algorithm numbers. This function MUST not change ERRNO. */ int _gpgme_map_pk_algo (int algo, gpgme_protocol_t protocol) { if (protocol == GPGME_PROTOCOL_OPENPGP) { switch (algo) { case 1: case 2: case 3: case 16: case 17: break; case 18: algo = GPGME_PK_ECDH; break; case 19: algo = GPGME_PK_ECDSA; break; case 20: break; default: algo = 0; break; /* Unknown. */ } } return algo; }