DOH: add test case 1650 and 2100

lib/doh.c

@@ -38,31 +38,6 @@
 #define DNS_CLASS_IN 0x01
 #define DOH_MAX_RESPONSE_SIZE 3000 /* bytes */
 
-typedef enum {
-  DNS_TYPE_A = 1,
-  DNS_TYPE_NS = 2,
-  DNS_TYPE_CNAME = 5,
-  DNS_TYPE_AAAA = 28
-} DNStype;
-
-#define MAX_ADDR 24
-
-typedef enum {
-  DOH_OK,
-  DOH_DNS_BAD_LABEL,    /* 1 */
-  DOH_DNS_OUT_OF_RANGE, /* 2 */
-  DOH_DNS_LABEL_LOOP,   /* 3 */
-  DOH_TOO_SMALL_BUFFER, /* 4 */
-  DOH_OUT_OF_MEM,       /* 5 */
-  DOH_DNS_RDATA_LEN,    /* 6 */
-  DOH_DNS_MALFORMAT,    /* 7 */
-  DOH_DNS_BAD_RCODE,    /* 8 - no such name */
-  DOH_DNS_UNEXPECTED_TYPE,  /* 9 */
-  DOH_DNS_UNEXPECTED_CLASS, /* 10 */
-  DOH_NO_CONTENT,           /* 11 */
-  DOH_DNS_BAD_ID            /* 12 */
-} DOHcode;
-
 static const char * const errors[]={
   "",
   "Bad label",
@@ -86,7 +61,13 @@ static const char *doh_strerror(DOHcode code)
   return "bad error code";
 }
 
-static DOHcode doh_encode(const char *host,
+#ifdef DEBUGBUILD
+#define UNITTEST
+#else
+#define UNITTEST static
+#endif
+
+UNITTEST DOHcode doh_encode(const char *host,
                             DNStype dnstype,
                             unsigned char *dnsp, /* buffer */
                             size_t len,  /* buffer size */
@@ -123,9 +104,11 @@ static DOHcode doh_encode(const char *host,
     }
     else
       labellen = strlen(hostp);
-    if(labellen > 63)
+    if(labellen > 63) {
       /* too long label, error out */
+      *olen = 0;
       return DOH_DNS_BAD_LABEL;
+    }
     *dnsp++ = (unsigned char)labellen;
     memcpy(dnsp, hostp, labellen);
     dnsp += labellen;
@@ -363,36 +346,10 @@ static unsigned int get32bit(unsigned char *doh, int index)
     (doh[index + 2] << 8) | doh[index + 3];
 }
 
-struct addr6 {
-  unsigned char byte[16];
-};
-
-struct cnamestore {
-  size_t len;       /* length of cname */
-  char *alloc;      /* allocated pointer */
-  size_t allocsize; /* allocated size */
-};
-
-struct dohaddr {
-  int type;
-  union {
-    unsigned int v4;
-    struct addr6 v6;
-  } ip;
-};
-
-struct dohentry {
-  unsigned int ttl;
-  int numaddr;
-  struct dohaddr addr[MAX_ADDR];
-  int numcname;
-  struct cnamestore cname[MAX_ADDR];
-};
-
 static DOHcode store_a(unsigned char *doh, int index, struct dohentry *d)
 {
   /* silently ignore addresses over the limit */
-  if(d->numaddr < MAX_ADDR) {
+  if(d->numaddr < DOH_MAX_ADDR) {
     struct dohaddr *a = &d->addr[d->numaddr];
     a->type = DNS_TYPE_A;
     a->ip.v4 = ntohl(get32bit(doh, index));
@@ -404,7 +361,7 @@ static DOHcode store_a(unsigned char *doh, int index, struct dohentry *d)
 static DOHcode store_aaaa(unsigned char *doh, int index, struct dohentry *d)
 {
   /* silently ignore addresses over the limit */
-  if(d->numaddr < MAX_ADDR) {
+  if(d->numaddr < DOH_MAX_ADDR) {
     struct dohaddr *a = &d->addr[d->numaddr];
     struct addr6 *inet6p = &a->ip.v6;
     a->type = DNS_TYPE_AAAA;
@@ -445,9 +402,14 @@ static DOHcode store_cname(unsigned char *doh,
                            unsigned int index,
                            struct dohentry *d)
 {
-  struct cnamestore *c = &d->cname[d->numcname++];
+  struct cnamestore *c;
   unsigned int loop = 128; /* a valid DNS name can never loop this much */
   unsigned char length;
+
+  if(d->numcname == DOH_MAX_CNAME)
+    return DOH_OK; /* skip! */
+
+  c = &d->cname[d->numcname++];
   do {
     if(index >= dohlen)
       return DOH_DNS_OUT_OF_RANGE;
@@ -530,7 +492,7 @@ static DOHcode rdata(unsigned char *doh,
   return DOH_OK;
 }
 
-static DOHcode doh_decode(unsigned char *doh,
+UNITTEST DOHcode doh_decode(unsigned char *doh,
                             size_t dohlen,
                             DNStype dnstype,
                             struct dohentry *d)
@@ -824,7 +786,7 @@ static const char *type2name(DNStype dnstype)
   return (dnstype == DNS_TYPE_A)?"A":"AAAA";
 }
 
-static void de_cleanup(struct dohentry *d)
+UNITTEST void de_cleanup(struct dohentry *d)
 {
   int i = 0;
   for(i = 0; i < d->numcname; i++) {

lib/doh.h

@@ -41,4 +41,69 @@ CURLcode Curl_doh_is_resolved(struct connectdata *conn,
 int Curl_doh_getsock(struct connectdata *conn, curl_socket_t *socks,
                      int numsocks);
 
+typedef enum {
+  DOH_OK,
+  DOH_DNS_BAD_LABEL,    /* 1 */
+  DOH_DNS_OUT_OF_RANGE, /* 2 */
+  DOH_DNS_LABEL_LOOP,   /* 3 */
+  DOH_TOO_SMALL_BUFFER, /* 4 */
+  DOH_OUT_OF_MEM,       /* 5 */
+  DOH_DNS_RDATA_LEN,    /* 6 */
+  DOH_DNS_MALFORMAT,    /* 7 */
+  DOH_DNS_BAD_RCODE,    /* 8 - no such name */
+  DOH_DNS_UNEXPECTED_TYPE,  /* 9 */
+  DOH_DNS_UNEXPECTED_CLASS, /* 10 */
+  DOH_NO_CONTENT,           /* 11 */
+  DOH_DNS_BAD_ID            /* 12 */
+} DOHcode;
+
+typedef enum {
+  DNS_TYPE_A = 1,
+  DNS_TYPE_NS = 2,
+  DNS_TYPE_CNAME = 5,
+  DNS_TYPE_AAAA = 28
+} DNStype;
+
+#define DOH_MAX_ADDR 24
+#define DOH_MAX_CNAME 4
+
+struct addr6 {
+  unsigned char byte[16];
+};
+
+struct cnamestore {
+  size_t len;       /* length of cname */
+  char *alloc;      /* allocated pointer */
+  size_t allocsize; /* allocated size */
+};
+
+struct dohaddr {
+  int type;
+  union {
+    unsigned int v4;
+    struct addr6 v6;
+  } ip;
+};
+
+struct dohentry {
+  unsigned int ttl;
+  int numaddr;
+  struct dohaddr addr[DOH_MAX_ADDR];
+  int numcname;
+  struct cnamestore cname[DOH_MAX_CNAME];
+};
+
+
+#ifdef DEBUGBUILD
+DOHcode doh_encode(const char *host,
+                   DNStype dnstype,
+                   unsigned char *dnsp, /* buffer */
+                   size_t len,  /* buffer size */
+                   size_t *olen); /* output length */
+DOHcode doh_decode(unsigned char *doh,
+                   size_t dohlen,
+                   DNStype dnstype,
+                   struct dohentry *d);
+void de_cleanup(struct dohentry *d);
+#endif
 #endif

tests/data/Makefile.inc

@@ -182,6 +182,8 @@ test1590 \
 test1600 test1601 test1602 test1603 test1604 test1605 test1606 test1607 \
 test1608 test1609 test1620 \
 \
+test1650 \
+\
 test1700 test1701 test1702 \
 \
 test1800 test1801 \
@@ -201,4 +203,6 @@ test2064 test2065 test2066 test2067 test2068 test2069 \
 test2070 test2071 test2072 test2073 \
 test2074 test2075 \
 \
+test2100 \
+\
 test3000 test3001

tests/data/test1650

@@ -0,0 +1,26 @@
+<testcase>
+<info>
+<keywords>
+unittest
+DOH
+</keywords>
+</info>
+
+#
+# Client-side
+<client>
+<server>
+none
+</server>
+<features>
+unittest
+</features>
+ <name>
+DOH
+ </name>
+<tool>
+unit1650
+</tool>
+</client>
+
+</testcase>

tests/unit/Makefile.inc

@@ -10,7 +10,8 @@ UNITPROGS = unit1300 unit1301 unit1302 unit1303 unit1304 unit1305 unit1307	\
  unit1330 unit1394 unit1395 unit1396 unit1397 unit1398	\
  unit1399	\
  unit1600 unit1601 unit1602 unit1603 unit1604 unit1605 unit1606 unit1607 \
- unit1608 unit1609 unit1620
+ unit1608 unit1609 unit1620 \
+ unit1650
 
 unit1300_SOURCES = unit1300.c $(UNITFILES)
 unit1300_CPPFLAGS = $(AM_CPPFLAGS)
@@ -98,3 +99,6 @@ unit1609_CPPFLAGS = $(AM_CPPFLAGS)
 
 unit1620_SOURCES = unit1620.c $(UNITFILES)
 unit1620_CPPFLAGS = $(AM_CPPFLAGS)
+
+unit1650_SOURCES = unit1650.c $(UNITFILES)
+unit1650_CPPFLAGS = $(AM_CPPFLAGS)

tests/unit/unit1650.c

@@ -0,0 +1,283 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+#include "curlcheck.h"
+
+#include "doh.h"
+
+static CURLcode unit_setup(void)
+{
+  return CURLE_OK;
+}
+
+static void unit_stop(void)
+{
+
+}
+
+#define DNS_PREAMBLE "\x00\x00\x01\x00\x00\x01\x00\x00\x00\x00\x00\x00"
+#define LABEL_TEST "\x04\x74\x65\x73\x74"
+#define LABEL_HOST "\x04\x68\x6f\x73\x74"
+#define LABEL_NAME "\x04\x6e\x61\x6d\x65"
+#define DNSA_TYPE "\x01"
+#define DNSAAAA_TYPE "\x1c"
+#define DNSA_EPILOGUE "\x00\x00" DNSA_TYPE "\x00\x01"
+#define DNSAAAA_EPILOGUE "\x00\x00" DNSAAAA_TYPE "\x00\x01"
+
+#define DNS_Q1 DNS_PREAMBLE LABEL_TEST LABEL_HOST LABEL_NAME DNSA_EPILOGUE
+#define DNS_Q2 DNS_PREAMBLE LABEL_TEST LABEL_HOST LABEL_NAME DNSAAAA_EPILOGUE
+
+struct dohrequest {
+  /* input */
+  const char *name;
+  DNStype type;
+
+  /* output */
+  const char *packet;
+  size_t size;
+  int rc;
+};
+
+
+static struct dohrequest req[] = {
+  {"test.host.name", DNS_TYPE_A, DNS_Q1, sizeof(DNS_Q1)-1, 0 },
+  {"test.host.name", DNS_TYPE_AAAA, DNS_Q2, sizeof(DNS_Q2)-1, 0 },
+  {"zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz"
+   ".host.name",
+   DNS_TYPE_AAAA, NULL, 0, DOH_DNS_BAD_LABEL }
+};
+
+struct dohresp {
+  /* input */
+  const char *packet;
+  size_t size;
+  DNStype type;
+
+  /* output */
+  int rc;
+  const char *out;
+};
+
+#define DNS_FOO_EXAMPLE_COM                                          \
+  "\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x03\x66\x6f\x6f" \
+  "\x07\x65\x78\x61\x6d\x70\x6c\x65\x03\x63\x6f\x6d\x00\x00\x01\x00" \
+  "\x01\xc0\x0c\x00\x01\x00\x01\x00\x00\x00\x37\x00\x04\x7f\x00\x00" \
+  "\x01"
+
+static const char full49[] = DNS_FOO_EXAMPLE_COM;
+
+static struct dohresp resp[] = {
+  {"\x00\x00", 2, DNS_TYPE_A, DOH_TOO_SMALL_BUFFER, NULL },
+  {"\x00\x01\x00\x01\x00\x01\x00\x01\x00\x01\x00\x01", 12,
+   DNS_TYPE_A, DOH_DNS_BAD_ID, NULL },
+  {"\x00\x00\x00\x01\x00\x01\x00\x01\x00\x01\x00\x01", 12,
+   DNS_TYPE_A, DOH_DNS_BAD_RCODE, NULL },
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x03\x66\x6f\x6f", 16,
+   DNS_TYPE_A, DOH_DNS_OUT_OF_RANGE, NULL },
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x03\x66\x6f\x6f\x00", 17,
+   DNS_TYPE_A, DOH_DNS_OUT_OF_RANGE, NULL },
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x03\x66\x6f\x6f\x00"
+   "\x00\x01\x00\x01", 21,
+   DNS_TYPE_A, DOH_DNS_OUT_OF_RANGE, NULL },
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x03\x66\x6f\x6f\x00"
+   "\x00\x01\x00\x01"
+   "\x04", 18,
+   DNS_TYPE_A, DOH_DNS_OUT_OF_RANGE, NULL },
+
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x04\x63\x75\x72"
+   "\x6c\x04\x63\x75\x72\x6c\x00\x00\x05\x00\x01\xc0\x0c\x00\x05\x00"
+   "\x01\x00\x00\x00\x37\x00\x11\x08\x61\x6e\x79\x77\x68\x65\x72\x65"
+   "\x06\x72\x65\x61\x6c\x6c\x79\x00", 56,
+   DNS_TYPE_A, DOH_OK, "anywhere.really "},
+
+  {DNS_FOO_EXAMPLE_COM, 49, DNS_TYPE_A, DOH_OK, "127.0.0.1 "},
+
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x04\x61\x61\x61"
+   "\x61\x07\x65\x78\x61\x6d\x70\x6c\x65\x03\x63\x6f\x6d\x00\x00\x1c"
+   "\x00\x01\xc0\x0c\x00\x1c\x00\x01\x00\x00\x00\x37\x00\x10\x20\x20"
+   "\x20\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x20", 62,
+   DNS_TYPE_AAAA, DOH_OK,
+   "2020:2020:0000:0000:0000:0000:0000:2020 " },
+
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x00\x04\x63\x75\x72"
+   "\x6c\x04\x63\x75\x72\x6c\x00\x00\x05\x00\x01\xc0\x0c\x00\x05\x00"
+   "\x01\x00\x00\x00\x37\x00"
+   "\x07\x03\x61\x6e\x79\xc0\x27\x00", 46,
+   DNS_TYPE_A, DOH_DNS_LABEL_LOOP, NULL},
+
+  /* packet with NSCOUNT == 1 */
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x01\x00\x00\x04\x61\x61\x61"
+   "\x61\x07\x65\x78\x61\x6d\x70\x6c\x65\x03\x63\x6f\x6d\x00\x00\x1c"
+   "\x00\x01\xc0\x0c\x00\x1c\x00\x01\x00\x00\x00\x37\x00\x10\x20\x20"
+   "\x20\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x20"
+   LABEL_TEST LABEL_HOST LABEL_NAME DNSAAAA_EPILOGUE "\x00\x00\x00\x01"
+   "\00\x04\x01\x01\x01\x01", /* RDDATA */
+
+   62 + 30,
+   DNS_TYPE_AAAA, DOH_OK,
+   "2020:2020:0000:0000:0000:0000:0000:2020 " },
+
+  /* packet with ARCOUNT == 1 */
+  {"\x00\x00\x01\x00\x00\x01\x00\x01\x00\x00\x00\x01\x04\x61\x61\x61"
+   "\x61\x07\x65\x78\x61\x6d\x70\x6c\x65\x03\x63\x6f\x6d\x00\x00\x1c"
+   "\x00\x01\xc0\x0c\x00\x1c\x00\x01\x00\x00\x00\x37\x00\x10\x20\x20"
+   "\x20\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x20"
+   LABEL_TEST LABEL_HOST LABEL_NAME DNSAAAA_EPILOGUE "\x00\x00\x00\x01"
+   "\00\x04\x01\x01\x01\x01", /* RDDATA */
+
+   62 + 30,
+   DNS_TYPE_AAAA, DOH_OK,
+   "2020:2020:0000:0000:0000:0000:0000:2020 " },
+
+};
+
+UNITTEST_START
+{
+  size_t size;
+  unsigned char buffer[256];
+  size_t i;
+  for(i = 0; i < sizeof(req) / sizeof(req[0]); i++) {
+    int rc = doh_encode(req[i].name, req[i].type,
+                        buffer, sizeof(buffer), &size);
+    if(rc != req[i].rc) {
+      fprintf(stderr, "req %d: Expected return code %d got %d\n", i,
+              req[i].rc, rc);
+      return 1;
+    }
+    else if(size != req[i].size) {
+      fprintf(stderr, "req %d: Expected size %d got %d\n", i,
+              (int)req[i].size, (int)size);
+      fprintf(stderr, "DNS encode made: %s\n", hexdump(buffer, size));
+      return 2;
+    }
+    else if(memcmp(req[i].packet, buffer, size)) {
+      fprintf(stderr, "DNS encode made: %s\n", hexdump(buffer, size));
+      fprintf(stderr, "... instead of: %s\n",
+             hexdump((unsigned char *)req[i].packet, size));
+      return 3;
+    }
+  }
+
+  for(i = 0; i < sizeof(resp) / sizeof(resp[0]); i++) {
+    struct dohentry d;
+    int rc;
+    char *ptr;
+    size_t len;
+    int u;
+    memset(&d, 0, sizeof(d));
+    rc = doh_decode((unsigned char *)resp[i].packet, resp[i].size,
+                    resp[i].type, &d);
+    if(rc != resp[i].rc) {
+      fprintf(stderr, "resp %d: Expected return code %d got %d\n", i,
+              resp[i].rc, rc);
+      return 4;
+    }
+    len = sizeof(buffer);
+    ptr = (char *)buffer;
+    for(u = 0; u < d.numaddr; u++) {
+      size_t o;
+      struct dohaddr *a;
+      a = &d.addr[u];
+      if(resp[i].type == DNS_TYPE_A) {
+        snprintf(ptr, len, "%d.%d.%d.%d ",
+                 a->ip.v4 & 0xff, (a->ip.v4>>8) & 0xff,
+                 (a->ip.v4>>16) & 0xff, a->ip.v4 >>24);
+        o = strlen(ptr);
+        len -= o;
+        ptr += o;
+      }
+      else {
+        int j;
+        for(j = 0; j < 16; j += 2) {
+          size_t l;
+          snprintf(ptr, len, "%s%02x%02x", j?":":"", a->ip.v6.byte[j],
+                   a->ip.v6.byte[j + 1]);
+          l = strlen(ptr);
+          len -= l;
+          ptr += l;
+        }
+        snprintf(ptr, len, " ");
+        len--;
+        ptr++;
+      }
+    }
+    for(u = 0; u < d.numcname; u++) {
+      size_t o;
+      snprintf(ptr, len, "%s ", d.cname[u].alloc);
+      o = strlen(ptr);
+      len -= o;
+      ptr += o;
+    }
+    de_cleanup(&d);
+    if(resp[i].out && strcmp((char *)buffer, resp[i].out)) {
+      fprintf(stderr, "resp %d: Expected %s got %s\n", i,
+              resp[i].out, buffer);
+      return 1;
+    }
+  }
+
+  {
+    /* pass all sizes into the decoder until full */
+    for(i = 0; i < sizeof(full49)-1; i++) {
+      struct dohentry d;
+      int rc;
+      memset(&d, 0, sizeof(d));
+      rc = doh_decode((unsigned char *)full49, i, DNS_TYPE_A, &d);
+      if(!rc) {
+        /* none of them should work */
+        fprintf(stderr, "%d: %d\n", i, rc);
+        return 5;
+      }
+    }
+    /* and try all pieces from the other end of the packet */
+    for(i = 1; i < sizeof(full49); i++) {
+      struct dohentry d;
+      int rc;
+      memset(&d, 0, sizeof(d));
+      rc = doh_decode((unsigned char *)&full49[i], sizeof(full49)-i-1,
+                      DNS_TYPE_A, &d);
+      if(!rc) {
+        /* none of them should work */
+        fprintf(stderr, "2 %d: %d\n", i, rc);
+        return 7;
+      }
+    }
+    {
+      int rc;
+      struct dohentry d;
+      struct dohaddr *a;
+      memset(&d, 0, sizeof(d));
+      rc = doh_decode((unsigned char *)full49, sizeof(full49)-1,
+                      DNS_TYPE_A, &d);
+      fail_if(d.numaddr != 1, "missing address");
+      a = &d.addr[i];
+      snprintf((char *)buffer, sizeof(buffer), "%d.%d.%d.%d\n",
+               a->ip.v4 & 0xff, (a->ip.v4>>8) & 0xff,
+               (a->ip.v4>>16) & 0xff, a->ip.v4 >>24);
+      if(rc && strcmp((char *)buffer, "127.0.0.1")) {
+        fprintf(stderr, "bad address decoded\n");
+        return 7;
+      }
+      fail_if(d.numcname, "bad cname counter");
+    }
+  }
+}
+UNITTEST_STOP