src/misc.c

   1 /*
   2     Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015,
   3     2016
   4     Ben Kibbey <bjk@luxsci.net>
   5
   6     This file is part of libpwmd.
   7
   8     Libpwmd is free software: you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation, either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     Libpwmd is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with Libpwmd.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21 #ifdef HAVE_CONFIG_H
  22 #include <config.h>
  23 #endif
  24
  25 #ifdef HAVE_LIMITS_H
  26 #include <limits.h>
  27 #endif
  28
  29 #ifdef HAVE_STDLIB_H
  30 #include <stdlib.h>
  31 #endif
  32
  33 #include <stdio.h>
  34 #include <unistd.h>
  35 #include <string.h>
  36 #include <errno.h>
  37 #include <ctype.h>
  38
  39 #ifndef LINE_MAX
  40 #define LINE_MAX        2048
  41 #endif
  42
  43 #include <libpwmd.h>
  44 #include "misc.h"
  45
  46 #ifdef HAVE_GETPWUID_R
  47 char *
  48 _expand_homedir (char *str, struct passwd *pw)
  49 {
  50   char *p = str;
  51   char *pwbuf = NULL;
  52   char *result;
  53   struct passwd t;
  54
  55   if (!p)
  56     return NULL;
  57
  58   if (*p != '~' || *(p + 1) != '/')
  59     return pwmd_strdup (p);
  60
  61   if (!pw)
  62     {
  63       pwbuf = _getpwuid (&t);
  64       if (!pwbuf)
  65         return NULL;
  66
  67       pw = &t;
  68     }
  69
  70   p += 2;
  71   result = pwmd_strdup_printf ("%s/%s", pw->pw_dir, p);
  72   pwmd_free (pwbuf);
  73   return result;
  74 }
  75
  76 char *
  77 _getpwuid (struct passwd *pwd)
  78 {
  79   size_t size = sysconf (_SC_GETPW_R_SIZE_MAX);
  80   struct passwd *result;
  81   char *buf;
  82   int n;
  83
  84   if (size == -1)
  85     size = 16384;
  86
  87   buf = pwmd_malloc (size);
  88   if (!buf)
  89     return NULL;
  90
  91   n = getpwuid_r (getuid (), pwd, buf, size, &result);
  92   if (n)
  93     {
  94       pwmd_free (buf);
  95       errno = n;
  96       return NULL;
  97     }
  98
  99   if (!result)
 100     {
 101       pwmd_free (buf);
 102       return NULL;
 103     }
 104
 105   errno = n;
 106   return buf;
 107 }
 108 #else
 109 char *
 110 _expand_homedir (char *str, struct passwd *pw)
 111 {
 112   char *p = str;
 113
 114   if (!p)
 115     return NULL;
 116
 117   if (*p != '~' || *(p + 1) != '/')
 118     return pwmd_strdup (p);
 119
 120   if (!pw)
 121     {
 122       pw = getpwuid (getuid ());
 123       if (!pw)
 124         return NULL;
 125     }
 126
 127   p += 2;
 128   return pwmd_strdup_printf ("%s/%s", pw->pw_dir, p);
 129 }
 130
 131 char *
 132 _getpwuid (struct passwd *pwd)
 133 {
 134   struct passwd *pw = getpwuid (getuid ());
 135
 136   if (!pw)
 137     return NULL;
 138
 139   *pwd = *pw;
 140   return pwmd_strdup ("");
 141 }
 142 #endif
 143
 144 /*
 145  * Borrowed from libassuan.
 146  */
 147 char *
 148 _percent_escape (const char *atext)
 149 {
 150   const unsigned char *s;
 151   int len;
 152   char *buf, *p;
 153
 154   if (!atext)
 155     return NULL;
 156
 157   len = strlen (atext) * 3 + 1;
 158   buf = (char *) pwmd_malloc (len);
 159
 160   if (!buf)
 161     return NULL;
 162
 163   p = buf;
 164
 165   for (s = (const unsigned char *) atext; *s; s++)
 166     {
 167       if (*s < ' ')
 168         {
 169           sprintf (p, "%%%02X", *s);
 170           p += 3;
 171         }
 172       else
 173         *p++ = *s;
 174     }
 175
 176   *p = 0;
 177   return buf;
 178 }
 179
 180 void
 181 update_pinentry_settings (pwm_t * pwm)
 182 {
 183   FILE *fp;
 184   char buf[LINE_MAX];
 185   char *p;
 186   struct passwd pw;
 187   char *pwbuf = _getpwuid (&pw);
 188
 189   if (!pwbuf)
 190     return;
 191
 192   snprintf (buf, sizeof (buf), "%s/.pwmd/pinentry.conf", pw.pw_dir);
 193
 194   if ((fp = fopen (buf, "r")) == NULL)
 195     {
 196       pwmd_free (pwbuf);
 197       return;
 198     }
 199
 200   while ((p = fgets (buf, sizeof (buf), fp)) != NULL)
 201     {
 202       char name[32] = {0}, val[256] = {0};
 203
 204       if (sscanf (p, " %31[a-zA-Z] = %255s", name, val) != 2)
 205         continue;
 206
 207       if (strcasecmp (name, "TTYNAME") == 0)
 208         {
 209           pwmd_free (pwm->pinentry_tty);
 210           pwm->pinentry_tty = pwmd_strdup (val);
 211           if (!pwm->pinentry_tty)
 212             goto fail;
 213         }
 214       else if (strcasecmp (name, "TTYTYPE") == 0)
 215         {
 216           pwmd_free (pwm->pinentry_term);
 217           pwm->pinentry_term = pwmd_strdup (val);
 218           if (!pwm->pinentry_term)
 219             goto fail;
 220         }
 221       else if (strcasecmp (name, "DISPLAY") == 0)
 222         {
 223           pwmd_free (pwm->pinentry_display);
 224           pwm->pinentry_display = pwmd_strdup (val);
 225           if (!pwm->pinentry_display)
 226             goto fail;
 227         }
 228       else if (strcasecmp (name, "PATH") == 0)
 229         {
 230           pwmd_free (pwm->pinentry_path);
 231           pwm->pinentry_path = _expand_homedir (val, &pw);
 232           if (!pwm->pinentry_path)
 233             goto fail;
 234         }
 235       else if (strcasecmp (name, "LC_MESSAGES") == 0)
 236         {
 237           pwmd_free (pwm->pinentry_lcmessages);
 238           pwm->pinentry_lcmessages = pwmd_strdup (val);
 239           if (!pwm->pinentry_lcmessages)
 240             goto fail;
 241         }
 242       else if (strcasecmp (name, "LC_CTYPE") == 0)
 243         {
 244           pwmd_free (pwm->pinentry_lcctype);
 245           pwm->pinentry_lcctype = pwmd_strdup (val);
 246           if (!pwm->pinentry_lcctype)
 247             goto fail;
 248         }
 249     }
 250
 251 fail:
 252   pwmd_free (pwbuf);
 253   fclose (fp);
 254 }
 255
 256 /* Common hostname parsing for urls. Handles both IPv4 and IPv6 hostname and
 257  * port specification.
 258  */
 259 gpg_error_t
 260 parse_hostname_common (const char *str, char **host, int *port)
 261 {
 262   const char *p = str;
 263   char *t = NULL;
 264
 265   /* IPv6 with optional port. */
 266   if (*p == '[')
 267     {
 268       p++;
 269       t = strchr (p, ']');
 270     }
 271   else
 272     {
 273       int n = 0;
 274       const char *x;
 275
 276       /* Handle IPv6 without proper braces around the IP. */
 277       for (x = p; *x; x++)
 278         {
 279           if (*x == ':')
 280             n++;
 281         }
 282
 283       if (n <= 1)
 284         t = strchr (p, ':');
 285     }
 286
 287   if (t)
 288     {
 289       size_t len = strlen (p) - strlen (t) + 1;
 290
 291       *host = pwmd_malloc (len);
 292       if (!*host)
 293         return gpg_error_from_errno (ENOMEM);
 294
 295       snprintf (*host, len, "%s", p);
 296       t++;
 297
 298       if (*t == ':')
 299         t++;
 300
 301       if (*t)
 302         *port = strtol (t, NULL, 10);
 303
 304       if (*t == '-')
 305         t++;
 306
 307       while (*t && isdigit (*t))
 308         t++;
 309
 310       p = t;
 311     }
 312   else
 313     {
 314       *host = pwmd_strdup (str);
 315       if (!*host)
 316         return gpg_error_from_errno (ENOMEM);
 317     }
 318
 319   return 0;
 320 }
 321
 322 char *
 323 bin2hex (const unsigned char *data, size_t len)
 324 {
 325   size_t size = len * 2 + 1;
 326   char buf[size]; // C99
 327   size_t n;
 328
 329   buf[0] = 0;
 330
 331   for (n = 0; n < len; n++)
 332     {
 333       char c[3];
 334
 335       sprintf (c, "%02X", data[n]);
 336       strcat (buf, c);
 337     }
 338
 339   return pwmd_strdup (buf);
 340 }