1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23#include "curl_setup.h"
24
25#if defined(USE_QSOSSL) || defined(USE_GSKIT) || defined(USE_NSS)
26
27#include <curl/curl.h>
28#include "urldata.h"
29#include "strequal.h"
30#include "hostcheck.h"
31#include "vtls/vtls.h"
32#include "sendf.h"
33#include "inet_pton.h"
34#include "curl_base64.h"
35#include "x509asn1.h"
36
37#define _MPRINTF_REPLACE /* use our functions only */
38#include <curl/mprintf.h>
39
40#include "curl_memory.h"
41/* The last #include file should be: */
42#include "memdebug.h"
43
44
45/* ASN.1 OIDs. */
46static const char       cnOID[] = "2.5.4.3";    /* Common name. */
47static const char       sanOID[] = "2.5.29.17"; /* Subject alternative name. */
48
49static const curl_OID   OIDtable[] = {
50  { "1.2.840.10040.4.1",        "dsa" },
51  { "1.2.840.10040.4.3",        "dsa-with-sha1" },
52  { "1.2.840.10045.2.1",        "ecPublicKey" },
53  { "1.2.840.10045.3.0.1",      "c2pnb163v1" },
54  { "1.2.840.10045.4.1",        "ecdsa-with-SHA1" },
55  { "1.2.840.10046.2.1",        "dhpublicnumber" },
56  { "1.2.840.113549.1.1.1",     "rsaEncryption" },
57  { "1.2.840.113549.1.1.2",     "md2WithRSAEncryption" },
58  { "1.2.840.113549.1.1.4",     "md5WithRSAEncryption" },
59  { "1.2.840.113549.1.1.5",     "sha1WithRSAEncryption" },
60  { "1.2.840.113549.1.1.10",    "RSASSA-PSS" },
61  { "1.2.840.113549.1.1.14",    "sha224WithRSAEncryption" },
62  { "1.2.840.113549.1.1.11",    "sha256WithRSAEncryption" },
63  { "1.2.840.113549.1.1.12",    "sha384WithRSAEncryption" },
64  { "1.2.840.113549.1.1.13",    "sha512WithRSAEncryption" },
65  { "1.2.840.113549.2.2",       "md2" },
66  { "1.2.840.113549.2.5",       "md5" },
67  { "1.3.14.3.2.26",            "sha1" },
68  { cnOID,                      "CN" },
69  { "2.5.4.4",                  "SN" },
70  { "2.5.4.5",                  "serialNumber" },
71  { "2.5.4.6",                  "C" },
72  { "2.5.4.7",                  "L" },
73  { "2.5.4.8",                  "ST" },
74  { "2.5.4.9",                  "streetAddress" },
75  { "2.5.4.10",                 "O" },
76  { "2.5.4.11",                 "OU" },
77  { "2.5.4.12",                 "title" },
78  { "2.5.4.13",                 "description" },
79  { "2.5.4.17",                 "postalCode" },
80  { "2.5.4.41",                 "name" },
81  { "2.5.4.42",                 "givenName" },
82  { "2.5.4.43",                 "initials" },
83  { "2.5.4.44",                 "generationQualifier" },
84  { "2.5.4.45",                 "X500UniqueIdentifier" },
85  { "2.5.4.46",                 "dnQualifier" },
86  { "2.5.4.65",                 "pseudonym" },
87  { "1.2.840.113549.1.9.1",     "emailAddress" },
88  { "2.5.4.72",                 "role" },
89  { sanOID,                     "subjectAltName" },
90  { "2.5.29.18",                "issuerAltName" },
91  { "2.5.29.19",                "basicConstraints" },
92  { "2.16.840.1.101.3.4.2.4",   "sha224" },
93  { "2.16.840.1.101.3.4.2.1",   "sha256" },
94  { "2.16.840.1.101.3.4.2.2",   "sha384" },
95  { "2.16.840.1.101.3.4.2.3",   "sha512" },
96  { (const char *) NULL,        (const char *) NULL }
97};
98
99/*
100 * Lightweight ASN.1 parser.
101 * In particular, it does not check for syntactic/lexical errors.
102 * It is intended to support certificate information gathering for SSL backends
103 * that offer a mean to get certificates as a whole, but do not supply
104 * entry points to get particular certificate sub-fields.
105 * Please note there is no pretention here to rewrite a full SSL library.
106 */
107
108
109const char * Curl_getASN1Element(curl_asn1Element * elem,
110                                 const char * beg, const char * end)
111{
112  unsigned char b;
113  unsigned long len;
114  curl_asn1Element lelem;
115
116  /* Get a single ASN.1 element into `elem', parse ASN.1 string at `beg'
117     ending at `end'.
118     Returns a pointer in source string after the parsed element, or NULL
119     if an error occurs. */
120
121  if(beg >= end || !*beg)
122    return (const char *) NULL;
123
124  /* Process header byte. */
125  b = (unsigned char) *beg++;
126  elem->constructed = (b & 0x20) != 0;
127  elem->class = (b >> 6) & 3;
128  b &= 0x1F;
129  if(b == 0x1F)
130    return (const char *) NULL; /* Long tag values not supported here. */
131  elem->tag = b;
132
133  /* Process length. */
134  if(beg >= end)
135    return (const char *) NULL;
136  b = (unsigned char) *beg++;
137  if(!(b & 0x80))
138    len = b;
139  else if(!(b &= 0x7F)) {
140    /* Unspecified length. Since we have all the data, we can determine the
141       effective length by skipping element until an end element is found. */
142    if(!elem->constructed)
143      return (const char *) NULL;
144    elem->beg = beg;
145    while(beg < end && *beg) {
146      beg = Curl_getASN1Element(&lelem, beg, end);
147      if(!beg)
148        return (const char *) NULL;
149    }
150    if(beg >= end)
151      return (const char *) NULL;
152    elem->end = beg;
153    return beg + 1;
154  }
155  else if(beg + b > end)
156    return (const char *) NULL; /* Does not fit in source. */
157  else {
158    /* Get long length. */
159    len = 0;
160    do {
161      if(len & 0xFF000000L)
162        return (const char *) NULL;  /* Lengths > 32 bits are not supported. */
163      len = (len << 8) | (unsigned char) *beg++;
164    } while(--b);
165  }
166  if((unsigned long) (end - beg) < len)
167    return (const char *) NULL;  /* Element data does not fit in source. */
168  elem->beg = beg;
169  elem->end = beg + len;
170  return elem->end;
171}
172
173static const curl_OID * searchOID(const char * oid)
174{
175  const curl_OID * op;
176
177  /* Search the null terminated OID or OID identifier in local table.
178     Return the table entry pointer or NULL if not found. */
179
180  for(op = OIDtable; op->numoid; op++)
181    if(!strcmp(op->numoid, oid) || curl_strequal(op->textoid, oid))
182      return op;
183
184  return (const curl_OID *) NULL;
185}
186
187static const char * bool2str(const char * beg, const char * end)
188{
189  /* Convert an ASN.1 Boolean value into its string representation.
190     Return the dynamically allocated string, or NULL if source is not an
191     ASN.1 Boolean value. */
192
193  if(end - beg != 1)
194    return (const char *) NULL;
195  return strdup(*beg? "TRUE": "FALSE");
196}
197
198static const char * octet2str(const char * beg, const char * end)
199{
200  size_t n = end - beg;
201  char * buf;
202
203  /* Convert an ASN.1 octet string to a printable string.
204     Return the dynamically allocated string, or NULL if an error occurs. */
205
206  buf = malloc(3 * n + 1);
207  if(buf)
208    for(n = 0; beg < end; n += 3)
209      snprintf(buf + n, 4, "%02x:", *(const unsigned char *) beg++);
210  return buf;
211}
212
213static const char * bit2str(const char * beg, const char * end)
214
215{
216  /* Convert an ASN.1 bit string to a printable string.
217     Return the dynamically allocated string, or NULL if an error occurs. */
218
219  if(++beg > end)
220    return (const char *) NULL;
221  return octet2str(beg, end);
222}
223
224static const char * int2str(const char * beg, const char * end)
225{
226  long val = 0;
227  size_t n = end - beg;
228
229  /* Convert an ASN.1 integer value into its string representation.
230     Return the dynamically allocated string, or NULL if source is not an
231     ASN.1 integer value. */
232
233  if(!n)
234    return (const char *) NULL;
235
236  if(n > 4)
237    return octet2str(beg, end);
238
239  /* Represent integers <= 32-bit as a single value. */
240  if(*beg & 0x80)
241    val = ~val;
242
243  do
244    val = (val << 8) | *(const unsigned char *) beg++;
245  while(beg < end);
246  return curl_maprintf("%s%lx", (val < 0 || val >= 10)? "0x": "", val);
247}
248
249static ssize_t
250utf8asn1str(char * * to, int type, const char * from, const char * end)
251{
252  size_t inlength = end - from;
253  int size = 1;
254  size_t outlength;
255  int charsize;
256  unsigned int wc;
257  char * buf;
258
259  /* Perform a lazy conversion from an ASN.1 typed string to UTF8. Allocate the
260     destination buffer dynamically. The allocation size will normally be too
261     large: this is to avoid buffer overflows.
262     Terminate the string with a nul byte and return the converted
263     string length. */
264
265  *to = (char *) NULL;
266  switch (type) {
267  case CURL_ASN1_BMP_STRING:
268    size = 2;
269    break;
270  case CURL_ASN1_UNIVERSAL_STRING:
271    size = 4;
272    break;
273  case CURL_ASN1_NUMERIC_STRING:
274  case CURL_ASN1_PRINTABLE_STRING:
275  case CURL_ASN1_TELETEX_STRING:
276  case CURL_ASN1_IA5_STRING:
277  case CURL_ASN1_VISIBLE_STRING:
278  case CURL_ASN1_UTF8_STRING:
279    break;
280  default:
281    return -1;  /* Conversion not supported. */
282  }
283
284  if(inlength % size)
285    return -1;  /* Length inconsistent with character size. */
286  buf = malloc(4 * (inlength / size) + 1);
287  if(!buf)
288    return -1;  /* Not enough memory. */
289
290  if(type == CURL_ASN1_UTF8_STRING) {
291    /* Just copy. */
292    outlength = inlength;
293    if(outlength)
294      memcpy(buf, from, outlength);
295  }
296  else {
297    for(outlength = 0; from < end;) {
298      wc = 0;
299      switch (size) {
300      case 4:
301        wc = (wc << 8) | *(const unsigned char *) from++;
302        wc = (wc << 8) | *(const unsigned char *) from++;
303      case 2:
304        wc = (wc << 8) | *(const unsigned char *) from++;
305      default: /* case 1: */
306        wc = (wc << 8) | *(const unsigned char *) from++;
307      }
308      charsize = 1;
309      if(wc >= 0x00000080) {
310        if(wc >= 0x00000800) {
311          if(wc >= 0x00010000) {
312            if(wc >= 0x00200000) {
313              free(buf);
314              return -1;        /* Invalid char. size for target encoding. */
315            }
316            buf[outlength + 3] = (char) (0x80 | (wc & 0x3F));
317            wc = (wc >> 6) | 0x00010000;
318            charsize++;
319          }
320          buf[outlength + 2] = (char) (0x80 | (wc & 0x3F));
321          wc = (wc >> 6) | 0x00000800;
322          charsize++;
323        }
324        buf[outlength + 1] = (char) (0x80 | (wc & 0x3F));
325        wc = (wc >> 6) | 0x000000C0;
326        charsize++;
327      }
328      buf[outlength] = (char) wc;
329      outlength += charsize;
330    }
331  }
332  buf[outlength] = '\0';
333  *to = buf;
334  return outlength;
335}
336
337static const char * string2str(int type, const char * beg, const char * end)
338{
339  char * buf;
340
341  /* Convert an ASN.1 String into its UTF-8 string representation.
342     Return the dynamically allocated string, or NULL if an error occurs. */
343
344  if(utf8asn1str(&buf, type, beg, end) < 0)
345    return (const char *) NULL;
346  return buf;
347}
348
349static int encodeUint(char * buf, int n, unsigned int x)
350{
351  int i = 0;
352  unsigned int y = x / 10;
353
354  /* Decimal ASCII encode unsigned integer `x' in the `n'-byte buffer at `buf'.
355     Return the total number of encoded digits, even if larger than `n'. */
356
357  if(y) {
358    i += encodeUint(buf, n, y);
359    x -= y * 10;
360  }
361  if(i < n)
362    buf[i] = (char) ('0' + x);
363  i++;
364  if(i < n)
365    buf[i] = '\0';      /* Store a terminator if possible. */
366  return i;
367}
368
369static int encodeOID(char * buf, int n, const char * beg, const char * end)
370{
371  int i = 0;
372  unsigned int x;
373  unsigned int y;
374
375  /* Convert an ASN.1 OID into its dotted string representation.
376     Store the result in th `n'-byte buffer at `buf'.
377     Return the converted string length, or -1 if an error occurs. */
378
379  /* Process the first two numbers. */
380  y = *(const unsigned char *) beg++;
381  x = y / 40;
382  y -= x * 40;
383  i += encodeUint(buf + i, n - i, x);
384  if(i < n)
385    buf[i] = '.';
386  i++;
387  i += encodeUint(buf + i, n - i, y);
388
389  /* Process the trailing numbers. */
390  while(beg < end) {
391    if(i < n)
392      buf[i] = '.';
393    i++;
394    x = 0;
395    do {
396      if(x & 0xFF000000)
397        return -1;
398      y = *(const unsigned char *) beg++;
399      x = (x << 7) | (y & 0x7F);
400    } while(y & 0x80);
401    i += encodeUint(buf + i, n - i, x);
402  }
403  if(i < n)
404    buf[i] = '\0';
405  return i;
406}
407
408static const char * OID2str(const char * beg, const char * end, bool symbolic)
409{
410  char * buf = (char *) NULL;
411  const curl_OID * op;
412  int n;
413
414  /* Convert an ASN.1 OID into its dotted or symbolic string representation.
415     Return the dynamically allocated string, or NULL if an error occurs. */
416
417  if(beg < end) {
418    n = encodeOID((char *) NULL, -1, beg, end);
419    if(n >= 0) {
420      buf = malloc(n + 1);
421      if(buf) {
422        encodeOID(buf, n, beg, end);
423        buf[n] = '\0';
424
425        if(symbolic) {
426          op = searchOID(buf);
427          if(op) {
428            free(buf);
429            buf = strdup(op->textoid);
430          }
431        }
432      }
433    }
434  }
435  return buf;
436}
437
438static const char * GTime2str(const char * beg, const char * end)
439{
440  const char * tzp;
441  const char * fracp;
442  char sec1, sec2;
443  size_t fracl;
444  size_t tzl;
445  const char * sep = "";
446
447  /* Convert an ASN.1 Generalized time to a printable string.
448     Return the dynamically allocated string, or NULL if an error occurs. */
449
450  for(fracp = beg; fracp < end && *fracp >= '0' && *fracp <= '9'; fracp++)
451    ;
452
453  /* Get seconds digits. */
454  sec1 = '0';
455  switch (fracp - beg - 12) {
456  case 0:
457    sec2 = '0';
458    break;
459  case 2:
460    sec1 = fracp[-2];
461  case 1:
462    sec2 = fracp[-1];
463    break;
464  default:
465    return (const char *) NULL;
466  }
467
468  /* Scan for timezone, measure fractional seconds. */
469  tzp = fracp;
470  fracl = 0;
471  if(fracp < end && (*fracp == '.' || *fracp == ',')) {
472    fracp++;
473    do
474      tzp++;
475    while(tzp < end && *tzp >= '0' && *tzp <= '9');
476    /* Strip leading zeroes in fractional seconds. */
477    for(fracl = tzp - fracp - 1; fracl && fracp[fracl - 1] == '0'; fracl--)
478      ;
479  }
480
481  /* Process timezone. */
482  if(tzp >= end)
483    ;           /* Nothing to do. */
484  else if(*tzp == 'Z') {
485    tzp = " GMT";
486    end = tzp + 4;
487  }
488  else {
489    sep = " ";
490    tzp++;
491  }
492
493  tzl = end - tzp;
494  return curl_maprintf("%.4s-%.2s-%.2s %.2s:%.2s:%c%c%s%.*s%s%.*s",
495                       beg, beg + 4, beg + 6,
496                       beg + 8, beg + 10, sec1, sec2,
497                       fracl? ".": "", fracl, fracp,
498                       sep, tzl, tzp);
499}
500
501static const char * UTime2str(const char * beg, const char * end)
502{
503  const char * tzp;
504  size_t tzl;
505  const char * sec;
506
507  /* Convert an ASN.1 UTC time to a printable string.
508     Return the dynamically allocated string, or NULL if an error occurs. */
509
510  for(tzp = beg; tzp < end && *tzp >= '0' && *tzp <= '9'; tzp++)
511    ;
512  /* Get the seconds. */
513  sec = beg + 10;
514  switch (tzp - sec) {
515  case 0:
516    sec = "00";
517  case 2:
518    break;
519  default:
520    return (const char *) NULL;
521  }
522
523  /* Process timezone. */
524  if(tzp >= end)
525    return (const char *) NULL;
526  if(*tzp == 'Z') {
527    tzp = "GMT";
528    end = tzp + 3;
529  }
530  else
531    tzp++;
532
533  tzl = end - tzp;
534  return curl_maprintf("%u%.2s-%.2s-%.2s %.2s:%.2s:%.2s %.*s",
535                       20 - (*beg >= '5'), beg, beg + 2, beg + 4,
536                       beg + 6, beg + 8, sec,
537                       tzl, tzp);
538}
539
540const char * Curl_ASN1tostr(curl_asn1Element * elem, int type)
541{
542  static const char zero = '\0';
543
544  /* Convert an ASN.1 element to a printable string.
545     Return the dynamically allocated string, or NULL if an error occurs. */
546
547  if(elem->constructed)
548    return (const char *) NULL; /* No conversion of structured elements. */
549
550  if(!type)
551    type = elem->tag;   /* Type not forced: use element tag as type. */
552
553  switch (type) {
554  case CURL_ASN1_BOOLEAN:
555    return bool2str(elem->beg, elem->end);
556  case CURL_ASN1_INTEGER:
557  case CURL_ASN1_ENUMERATED:
558    return int2str(elem->beg, elem->end);
559  case CURL_ASN1_BIT_STRING:
560    return bit2str(elem->beg, elem->end);
561  case CURL_ASN1_OCTET_STRING:
562    return octet2str(elem->beg, elem->end);
563  case CURL_ASN1_NULL:
564    return strdup(&zero);
565  case CURL_ASN1_OBJECT_IDENTIFIER:
566    return OID2str(elem->beg, elem->end, TRUE);
567  case CURL_ASN1_UTC_TIME:
568    return UTime2str(elem->beg, elem->end);
569  case CURL_ASN1_GENERALIZED_TIME:
570    return GTime2str(elem->beg, elem->end);
571  case CURL_ASN1_UTF8_STRING:
572  case CURL_ASN1_NUMERIC_STRING:
573  case CURL_ASN1_PRINTABLE_STRING:
574  case CURL_ASN1_TELETEX_STRING:
575  case CURL_ASN1_IA5_STRING:
576  case CURL_ASN1_VISIBLE_STRING:
577  case CURL_ASN1_UNIVERSAL_STRING:
578  case CURL_ASN1_BMP_STRING:
579    return string2str(type, elem->beg, elem->end);
580  }
581
582  return (const char *) NULL;   /* Unsupported. */
583}
584
585static ssize_t encodeDN(char * buf, size_t n, curl_asn1Element * dn)
586{
587  curl_asn1Element rdn;
588  curl_asn1Element atv;
589  curl_asn1Element oid;
590  curl_asn1Element value;
591  size_t l = 0;
592  const char * p1;
593  const char * p2;
594  const char * p3;
595  const char * str;
596
597  /* ASCII encode distinguished name at `dn' into the `n'-byte buffer at `buf'.
598     Return the total string length, even if larger than `n'. */
599
600  for(p1 = dn->beg; p1 < dn->end;) {
601    p1 = Curl_getASN1Element(&rdn, p1, dn->end);
602    for(p2 = rdn.beg; p2 < rdn.end;) {
603      p2 = Curl_getASN1Element(&atv, p2, rdn.end);
604      p3 = Curl_getASN1Element(&oid, atv.beg, atv.end);
605      Curl_getASN1Element(&value, p3, atv.end);
606      str = Curl_ASN1tostr(&oid, 0);
607      if(!str)
608        return -1;
609
610      /* Encode delimiter.
611         If attribute has a short uppercase name, delimiter is ", ". */
612      if(l) {
613        for(p3 = str; isupper(*p3); p3++)
614          ;
615        for(p3 = (*p3 || p3 - str > 2)? "/": ", "; *p3; p3++) {
616          if(l < n)
617            buf[l] = *p3;
618          l++;
619        }
620      }
621
622      /* Encode attribute name. */
623      for(p3 = str; *p3; p3++) {
624        if(l < n)
625          buf[l] = *p3;
626        l++;
627      }
628      free((char *) str);
629
630      /* Generate equal sign. */
631      if(l < n)
632        buf[l] = '=';
633      l++;
634
635      /* Generate value. */
636      str = Curl_ASN1tostr(&value, 0);
637      if(!str)
638        return -1;
639      for(p3 = str; *p3; p3++) {
640        if(l < n)
641          buf[l] = *p3;
642        l++;
643      }
644      free((char *) str);
645    }
646  }
647
648  return l;
649}
650
651const char * Curl_DNtostr(curl_asn1Element * dn)
652{
653  char * buf = (char *) NULL;
654  ssize_t n = encodeDN(buf, 0, dn);
655
656  /* Convert an ASN.1 distinguished name into a printable string.
657     Return the dynamically allocated string, or NULL if an error occurs. */
658
659  if(n >= 0) {
660    buf = malloc(n + 1);
661    if(buf) {
662      encodeDN(buf, n + 1, dn);
663      buf[n] = '\0';
664    }
665  }
666  return (const char *) buf;
667}
668
669/*
670 * X509 parser.
671 */
672
673void Curl_parseX509(curl_X509certificate * cert,
674                    const char * beg, const char * end)
675{
676  curl_asn1Element elem;
677  curl_asn1Element tbsCertificate;
678  const char * ccp;
679  static const char defaultVersion = 0;  /* v1. */
680
681  /* ASN.1 parse an X509 certificate into structure subfields.
682     Syntax is assumed to have already been checked by the SSL backend.
683     See RFC 5280. */
684
685  cert->certificate.beg = beg;
686  cert->certificate.end = end;
687
688  /* Get the sequence content. */
689  Curl_getASN1Element(&elem, beg, end);
690  beg = elem.beg;
691  end = elem.end;
692
693  /* Get tbsCertificate. */
694  beg = Curl_getASN1Element(&tbsCertificate, beg, end);
695  /* Skip the signatureAlgorithm. */
696  beg = Curl_getASN1Element(&cert->signatureAlgorithm, beg, end);
697  /* Get the signatureValue. */
698  Curl_getASN1Element(&cert->signature, beg, end);
699
700  /* Parse TBSCertificate. */
701  beg = tbsCertificate.beg;
702  end = tbsCertificate.end;
703  /* Get optional version, get serialNumber. */
704  cert->version.beg = &defaultVersion;
705  cert->version.end = &defaultVersion + sizeof defaultVersion;;
706  beg = Curl_getASN1Element(&elem, beg, end);
707  if(elem.tag == 0) {
708    Curl_getASN1Element(&cert->version, elem.beg, elem.end);
709    beg = Curl_getASN1Element(&elem, beg, end);
710  }
711  cert->serialNumber = elem;
712  /* Get signature algorithm. */
713  beg = Curl_getASN1Element(&cert->signatureAlgorithm, beg, end);
714  /* Get issuer. */
715  beg = Curl_getASN1Element(&cert->issuer, beg, end);
716  /* Get notBefore and notAfter. */
717  beg = Curl_getASN1Element(&elem, beg, end);
718  ccp = Curl_getASN1Element(&cert->notBefore, elem.beg, elem.end);
719  Curl_getASN1Element(&cert->notAfter, ccp, elem.end);
720  /* Get subject. */
721  beg = Curl_getASN1Element(&cert->subject, beg, end);
722  /* Get subjectPublicKeyAlgorithm and subjectPublicKey. */
723  beg = Curl_getASN1Element(&elem, beg, end);
724  ccp = Curl_getASN1Element(&cert->subjectPublicKeyAlgorithm,
725                            elem.beg, elem.end);
726  Curl_getASN1Element(&cert->subjectPublicKey, ccp, elem.end);
727  /* Get optional issuerUiqueID, subjectUniqueID and extensions. */
728  cert->issuerUniqueID.tag = cert->subjectUniqueID.tag = 0;
729  cert->extensions.tag = elem.tag = 0;
730  cert->issuerUniqueID.beg = cert->issuerUniqueID.end = "";
731  cert->subjectUniqueID.beg = cert->subjectUniqueID.end = "";
732  cert->extensions.beg = cert->extensions.end = "";
733  if(beg < end)
734    beg = Curl_getASN1Element(&elem, beg, end);
735  if(elem.tag == 1) {
736    cert->issuerUniqueID = elem;
737    if(beg < end)
738      beg = Curl_getASN1Element(&elem, beg, end);
739  }
740  if(elem.tag == 2) {
741    cert->subjectUniqueID = elem;
742    if(beg < end)
743      beg = Curl_getASN1Element(&elem, beg, end);
744  }
745  if(elem.tag == 3)
746    Curl_getASN1Element(&cert->extensions, elem.beg, elem.end);
747}
748
749static size_t copySubstring(char * to, const char * from)
750{
751  size_t i;
752
753  /* Copy at most 64-characters, terminate with a newline and returns the
754     effective number of stored characters. */
755
756  for(i = 0; i < 64; i++) {
757    to[i] = *from;
758    if(!*from++)
759      break;
760  }
761
762  to[i++] = '\n';
763  return i;
764}
765
766static const char * dumpAlgo(curl_asn1Element * param,
767                             const char * beg, const char * end)
768{
769  curl_asn1Element oid;
770
771  /* Get algorithm parameters and return algorithm name. */
772
773  beg = Curl_getASN1Element(&oid, beg, end);
774  param->tag = 0;
775  param->beg = param->end = end;
776  if(beg < end)
777    Curl_getASN1Element(param, beg, end);
778  return OID2str(oid.beg, oid.end, TRUE);
779}
780
781static void do_pubkey_field(struct SessionHandle * data, int certnum,
782                            const char * label, curl_asn1Element * elem)
783{
784  const char * output;
785
786  /* Generate a certificate information record for the public key. */
787
788  output = Curl_ASN1tostr(elem, 0);
789  if(output) {
790    if(data->set.ssl.certinfo)
791      Curl_ssl_push_certinfo(data, certnum, label, output);
792    if(!certnum)
793      infof(data, "   %s: %s\n", label, output);
794    free((char *) output);
795  }
796}
797
798static void do_pubkey(struct SessionHandle * data, int certnum,
799                      const char * algo, curl_asn1Element * param,
800                      curl_asn1Element * pubkey)
801{
802  curl_asn1Element elem;
803  curl_asn1Element pk;
804  const char * p;
805  const char * q;
806  unsigned long len;
807  unsigned int i;
808
809  /* Generate all information records for the public key. */
810
811  /* Get the public key (single element). */
812  Curl_getASN1Element(&pk, pubkey->beg + 1, pubkey->end);
813
814  if(curl_strequal(algo, "rsaEncryption")) {
815    p = Curl_getASN1Element(&elem, pk.beg, pk.end);
816    /* Compute key length. */
817    for(q = elem.beg; !*q && q < elem.end; q++)
818      ;
819    len = (elem.end - q) * 8;
820    if(len)
821      for(i = *(unsigned char *) q; !(i & 0x80); i <<= 1)
822        len--;
823    if(len > 32)
824      elem.beg = q;     /* Strip leading zero bytes. */
825    if(!certnum)
826      infof(data, "   RSA Public Key (%lu bits)\n", len);
827    if(data->set.ssl.certinfo) {
828      q = curl_maprintf("%lu", len);
829      if(q) {
830        Curl_ssl_push_certinfo(data, certnum, "RSA Public Key", q);
831        free((char *) q);
832      }
833    }
834    /* Generate coefficients. */
835    do_pubkey_field(data, certnum, "rsa(n)", &elem);
836    Curl_getASN1Element(&elem, p, pk.end);
837    do_pubkey_field(data, certnum, "rsa(e)", &elem);
838  }
839  else if(curl_strequal(algo, "dsa")) {
840    p = Curl_getASN1Element(&elem, param->beg, param->end);
841    do_pubkey_field(data, certnum, "dsa(p)", &elem);
842    p = Curl_getASN1Element(&elem, p, param->end);
843    do_pubkey_field(data, certnum, "dsa(q)", &elem);
844    Curl_getASN1Element(&elem, p, param->end);
845    do_pubkey_field(data, certnum, "dsa(g)", &elem);
846    do_pubkey_field(data, certnum, "dsa(pub_key)", &pk);
847  }
848  else if(curl_strequal(algo, "dhpublicnumber")) {
849    p = Curl_getASN1Element(&elem, param->beg, param->end);
850    do_pubkey_field(data, certnum, "dh(p)", &elem);
851    Curl_getASN1Element(&elem, param->beg, param->end);
852    do_pubkey_field(data, certnum, "dh(g)", &elem);
853    do_pubkey_field(data, certnum, "dh(pub_key)", &pk);
854  }
855#if 0 /* Patent-encumbered. */
856  else if(curl_strequal(algo, "ecPublicKey")) {
857    /* Left TODO. */
858  }
859#endif
860}
861
862CURLcode Curl_extract_certinfo(struct connectdata * conn,
863                               int certnum,
864                               const char * beg,
865                               const char * end)
866{
867  curl_X509certificate cert;
868  struct SessionHandle * data = conn->data;
869  curl_asn1Element param;
870  const char * ccp;
871  char * cp1;
872  size_t cl1;
873  char * cp2;
874  CURLcode cc;
875  unsigned long version;
876  size_t i;
877  size_t j;
878
879  if(!data->set.ssl.certinfo)
880    if(certnum)
881      return CURLE_OK;
882
883  /* Prepare the certificate information for curl_easy_getinfo(). */
884
885  /* Extract the certificate ASN.1 elements. */
886  Curl_parseX509(&cert, beg, end);
887
888  /* Subject. */
889  ccp = Curl_DNtostr(&cert.subject);
890  if(!ccp)
891    return CURLE_OUT_OF_MEMORY;
892  if(data->set.ssl.certinfo)
893    Curl_ssl_push_certinfo(data, certnum, "Subject", ccp);
894  if(!certnum)
895    infof(data, "%2d Subject: %s\n", certnum, ccp);
896  free((char *) ccp);
897
898  /* Issuer. */
899  ccp = Curl_DNtostr(&cert.issuer);
900  if(!ccp)
901    return CURLE_OUT_OF_MEMORY;
902  if(data->set.ssl.certinfo)
903    Curl_ssl_push_certinfo(data, certnum, "Issuer", ccp);
904  if(!certnum)
905    infof(data, "   Issuer: %s\n", ccp);
906  free((char *) ccp);
907
908  /* Version (always fits in less than 32 bits). */
909  version = 0;
910  for(ccp = cert.version.beg; ccp < cert.version.end; ccp++)
911    version = (version << 8) | *(const unsigned char *) ccp;
912  if(data->set.ssl.certinfo) {
913    ccp = curl_maprintf("%lx", version);
914    if(!ccp)
915      return CURLE_OUT_OF_MEMORY;
916    Curl_ssl_push_certinfo(data, certnum, "Version", ccp);
917    free((char *) ccp);
918  }
919  if(!certnum)
920    infof(data, "   Version: %lu (0x%lx)\n", version + 1, version);
921
922  /* Serial number. */
923  ccp = Curl_ASN1tostr(&cert.serialNumber, 0);
924  if(!ccp)
925    return CURLE_OUT_OF_MEMORY;
926  if(data->set.ssl.certinfo)
927    Curl_ssl_push_certinfo(data, certnum, "Serial Number", ccp);
928  if(!certnum)
929    infof(data, "   Serial Number: %s\n", ccp);
930  free((char *) ccp);
931
932  /* Signature algorithm .*/
933  ccp = dumpAlgo(&param, cert.signatureAlgorithm.beg,
934                 cert.signatureAlgorithm.end);
935  if(!ccp)
936    return CURLE_OUT_OF_MEMORY;
937  if(data->set.ssl.certinfo)
938    Curl_ssl_push_certinfo(data, certnum, "Signature Algorithm", ccp);
939  if(!certnum)
940    infof(data, "   Signature Algorithm: %s\n", ccp);
941  free((char *) ccp);
942
943  /* Start Date. */
944  ccp = Curl_ASN1tostr(&cert.notBefore, 0);
945  if(!ccp)
946    return CURLE_OUT_OF_MEMORY;
947  if(data->set.ssl.certinfo)
948    Curl_ssl_push_certinfo(data, certnum, "Start Date", ccp);
949  if(!certnum)
950    infof(data, "   Start Date: %s\n", ccp);
951  free((char *) ccp);
952
953  /* Expire Date. */
954  ccp = Curl_ASN1tostr(&cert.notAfter, 0);
955  if(!ccp)
956    return CURLE_OUT_OF_MEMORY;
957  if(data->set.ssl.certinfo)
958    Curl_ssl_push_certinfo(data, certnum, "Expire Date", ccp);
959  if(!certnum)
960    infof(data, "   Expire Date: %s\n", ccp);
961  free((char *) ccp);
962
963  /* Public Key Algorithm. */
964  ccp = dumpAlgo(&param, cert.subjectPublicKeyAlgorithm.beg,
965                 cert.subjectPublicKeyAlgorithm.end);
966  if(!ccp)
967    return CURLE_OUT_OF_MEMORY;
968  if(data->set.ssl.certinfo)
969    Curl_ssl_push_certinfo(data, certnum, "Public Key Algorithm", ccp);
970  if(!certnum)
971    infof(data, "   Public Key Algorithm: %s\n", ccp);
972  do_pubkey(data, certnum, ccp, &param, &cert.subjectPublicKey);
973  free((char *) ccp);
974
975/* TODO: extensions. */
976
977  /* Signature. */
978  ccp = Curl_ASN1tostr(&cert.signature, 0);
979  if(!ccp)
980    return CURLE_OUT_OF_MEMORY;
981  if(data->set.ssl.certinfo)
982    Curl_ssl_push_certinfo(data, certnum, "Signature", ccp);
983  if(!certnum)
984    infof(data, "   Signature: %s\n", ccp);
985  free((char *) ccp);
986
987  /* Generate PEM certificate. */
988  cc = Curl_base64_encode(data, cert.certificate.beg,
989                          cert.certificate.end - cert.certificate.beg,
990                          &cp1, &cl1);
991  if(cc != CURLE_OK)
992    return cc;
993  /* Compute the number of characters in final certificate string. Format is:
994     -----BEGIN CERTIFICATE-----\n
995     <max 64 base64 characters>\n
996     .
997     .
998     .
999     -----END CERTIFICATE-----\n
1000   */
1001  i = 28 + cl1 + (cl1 + 64 - 1) / 64 + 26;
1002  cp2 = malloc(i + 1);
1003  if(!cp2) {
1004    free(cp1);
1005    return CURLE_OUT_OF_MEMORY;
1006  }
1007  /* Build the certificate string. */
1008  i = copySubstring(cp2, "-----BEGIN CERTIFICATE-----");
1009  for(j = 0; j < cl1; j += 64)
1010    i += copySubstring(cp2 + i, cp1 + j);
1011  i += copySubstring(cp2 + i, "-----END CERTIFICATE-----");
1012  cp2[i] = '\0';
1013  free(cp1);
1014  if(data->set.ssl.certinfo)
1015    Curl_ssl_push_certinfo(data, certnum, "Cert", cp2);
1016  if(!certnum)
1017    infof(data, "%s\n", cp2);
1018  free(cp2);
1019  return CURLE_OK;
1020}
1021
1022#endif /* USE_QSOSSL or USE_GSKIT or USE_NSS */
1023
1024#if defined(USE_QSOSSL) || defined(USE_GSKIT)
1025
1026static const char * checkOID(const char * beg, const char * end,
1027                             const char * oid)
1028{
1029  curl_asn1Element e;
1030  const char * ccp;
1031  const char * p;
1032  bool matched;
1033
1034  /* Check if first ASN.1 element at `beg' is the given OID.
1035     Return a pointer in the source after the OID if found, else NULL. */
1036
1037  ccp = Curl_getASN1Element(&e, beg, end);
1038  if(!ccp || e.tag != CURL_ASN1_OBJECT_IDENTIFIER)
1039    return (const char *) NULL;
1040
1041  p = OID2str(e.beg, e.end, FALSE);
1042  if(!p)
1043    return (const char *) NULL;
1044
1045  matched = !strcmp(p, oid);
1046  free((char *) p);
1047  return matched? ccp: (const char *) NULL;
1048}
1049
1050CURLcode Curl_verifyhost(struct connectdata * conn,
1051                         const char * beg, const char * end)
1052{
1053  struct SessionHandle * data = conn->data;
1054  curl_X509certificate cert;
1055  curl_asn1Element dn;
1056  curl_asn1Element elem;
1057  curl_asn1Element ext;
1058  curl_asn1Element name;
1059  int i;
1060  const char * p;
1061  const char * q;
1062  char * dnsname;
1063  int matched = -1;
1064  size_t addrlen = (size_t) -1;
1065  ssize_t len;
1066#ifdef ENABLE_IPV6
1067  struct in6_addr addr;
1068#else
1069  struct in_addr addr;
1070#endif
1071
1072  /* Verify that connection server matches info in X509 certificate at
1073     `beg'..`end'. */
1074
1075  if(!data->set.ssl.verifyhost)
1076    return CURLE_OK;
1077
1078  if(!beg)
1079    return CURLE_PEER_FAILED_VERIFICATION;
1080  Curl_parseX509(&cert, beg, end);
1081
1082  /* Get the server IP address. */
1083#ifdef ENABLE_IPV6
1084  if(conn->bits.ipv6_ip && Curl_inet_pton(AF_INET6, conn->host.name, &addr))
1085    addrlen = sizeof(struct in6_addr);
1086  else
1087#endif
1088  if(Curl_inet_pton(AF_INET, conn->host.name, &addr))
1089    addrlen = sizeof(struct in_addr);
1090
1091  /* Process extensions. */
1092  for(p = cert.extensions.beg; p < cert.extensions.end && matched != 1;) {
1093    p = Curl_getASN1Element(&ext, p, cert.extensions.end);
1094    /* Check if extension is a subjectAlternativeName. */
1095    ext.beg = checkOID(ext.beg, ext.end, sanOID);
1096    if(ext.beg) {
1097      ext.beg = Curl_getASN1Element(&elem, ext.beg, ext.end);
1098      /* Skip critical if present. */
1099      if(elem.tag == CURL_ASN1_BOOLEAN)
1100        ext.beg = Curl_getASN1Element(&elem, ext.beg, ext.end);
1101      /* Parse the octet string contents: is a single sequence. */
1102      Curl_getASN1Element(&elem, elem.beg, elem.end);
1103      /* Check all GeneralNames. */
1104      for(q = elem.beg; matched != 1 && q < elem.end;) {
1105        q = Curl_getASN1Element(&name, q, elem.end);
1106        switch (name.tag) {
1107        case 2: /* DNS name. */
1108          i = 0;
1109          len = utf8asn1str(&dnsname, CURL_ASN1_IA5_STRING,
1110                            name.beg, name.end);
1111          if(len > 0)
1112            if(strlen(dnsname) == (size_t) len)
1113              i = Curl_cert_hostcheck((const char *) dnsname, conn->host.name);
1114          if(dnsname)
1115            free(dnsname);
1116          if(!i)
1117            return CURLE_PEER_FAILED_VERIFICATION;
1118          matched = i;
1119          break;
1120
1121        case 7: /* IP address. */
1122          matched = (size_t) (name.end - q) == addrlen &&
1123                    !memcmp(&addr, q, addrlen);
1124          break;
1125        }
1126      }
1127    }
1128  }
1129
1130  switch (matched) {
1131  case 1:
1132    /* an alternative name matched the server hostname */
1133    infof(data, "\t subjectAltName: %s matched\n", conn->host.dispname);
1134    return CURLE_OK;
1135  case 0:
1136    /* an alternative name field existed, but didn't match and then
1137       we MUST fail */
1138    infof(data, "\t subjectAltName does not match %s\n", conn->host.dispname);
1139    return CURLE_PEER_FAILED_VERIFICATION;
1140  }
1141
1142  /* Process subject. */
1143  name.beg = name.end = "";
1144  q = cert.subject.beg;
1145  /* we have to look to the last occurrence of a commonName in the
1146     distinguished one to get the most significant one. */
1147  while(q < cert.subject.end) {
1148    q = Curl_getASN1Element(&dn, q, cert.subject.end);
1149    for(p = dn.beg; p < dn.end;) {
1150      p = Curl_getASN1Element(&elem, p, dn.end);
1151      /* We have a DN's AttributeTypeAndValue: check it in case it's a CN. */
1152      elem.beg = checkOID(elem.beg, elem.end, cnOID);
1153      if(elem.beg)
1154        name = elem;    /* Latch CN. */
1155    }
1156  }
1157
1158  /* Check the CN if found. */
1159  if(!Curl_getASN1Element(&elem, name.beg, name.end))
1160    failf(data, "SSL: unable to obtain common name from peer certificate");
1161  else {
1162    len = utf8asn1str(&dnsname, elem.tag, elem.beg, elem.end);
1163    if(len < 0) {
1164      free(dnsname);
1165      return CURLE_OUT_OF_MEMORY;
1166    }
1167    if(strlen(dnsname) != (size_t) len)         /* Nul byte in string ? */
1168      failf(data, "SSL: illegal cert name field");
1169    else if(Curl_cert_hostcheck((const char *) dnsname, conn->host.name)) {
1170      infof(data, "\t common name: %s (matched)\n", dnsname);
1171      free(dnsname);
1172      return CURLE_OK;
1173    }
1174    else
1175      failf(data, "SSL: certificate subject name '%s' does not match "
1176            "target host name '%s'", dnsname, conn->host.dispname);
1177    free(dnsname);
1178  }
1179
1180  return CURLE_PEER_FAILED_VERIFICATION;
1181}
1182
1183#endif /* USE_QSOSSL or USE_GSKIT */
1184