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Diffstat (limited to 'src/conversion.c')
-rw-r--r-- | src/conversion.c | 414 |
1 files changed, 414 insertions, 0 deletions
diff --git a/src/conversion.c b/src/conversion.c new file mode 100644 index 0000000..356200c --- /dev/null +++ b/src/conversion.c @@ -0,0 +1,414 @@ +/* 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 <config.h> +#endif + +#include <stdlib.h> +#include <string.h> +#ifdef HAVE_SYS_TYPES_H + /* Solaris 8 needs sys/types.h before time.h. */ +# include <sys/types.h> +#endif +#include <time.h> +#include <errno.h> + +#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); +} |