GNUnet  0.20.0
nss_gns_query.h File Reference
#include <inttypes.h>
Include dependency graph for nss_gns_query.h:
This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures

struct  ipv4_address_t
 
struct  ipv6_address_t
 
struct  userdata
 

Macros

#define MAX_ENTRIES   16
 Parts taken from nss-mdns. More...
 

Functions

int gns_resolve_name (int af, const char *name, struct userdata *userdata)
 Wrapper function that uses gnunet-gns cli tool to resolve an IPv4/6 address. More...
 

Macro Definition Documentation

◆ MAX_ENTRIES

#define MAX_ENTRIES   16

Parts taken from nss-mdns.

Definition at line 29 of file nss_gns_query.h.

Function Documentation

◆ gns_resolve_name()

int gns_resolve_name ( int  af,
const char *  name,
struct userdata u 
)

Wrapper function that uses gnunet-gns cli tool to resolve an IPv4/6 address.

Parameters
afaddress family
namethe name to resolve
uthe userdata (result struct)
Returns
-1 on internal error, -2 if request is not for GNS, -3 on timeout, else 0

Definition at line 58 of file nss_gns_query.c.

59 {
60  FILE *p;
61  char line[128];
62  int ret;
63  int retry = 0;
64  int out[2];
65  pid_t pid;
66 
67  if (0 == getuid ())
68  return -2; /* GNS via NSS is NEVER for root */
69 
70 query_gns:
71  if (0 != pipe (out))
72  return -1;
73  pid = fork ();
74  if (-1 == pid)
75  return -1;
76  if (0 == pid)
77  {
78  char *argv[] = { "gnunet-gns",
79  "-r", /* Raw output for easier parsing */
80  "-d", /* DNS compatibility (allow IDNA names, no UTF-8) */
81  "-t",
82  (AF_INET6 == af) ? "AAAA" : "A",
83  "-u",
84  (char *) name,
85  "-T",
86  TIMEOUT,
87  NULL };
88 
89  (void) close (STDOUT_FILENO);
90  if ((0 != close (out[0])) ||
91  (STDOUT_FILENO != dup2 (out[1], STDOUT_FILENO)))
92  _exit (1);
93  (void) execvp ("gnunet-gns", argv);
94  _exit (1);
95  }
96  (void) close (out[1]);
97  p = fdopen (out[0], "r");
98  if (NULL == p)
99  {
100  kwait (pid);
101  return -1;
102  }
103  while (NULL != fgets (line, sizeof(line), p))
104  {
105  if (u->count >= MAX_ENTRIES)
106  break;
107  if (line[strlen (line) - 1] == '\n')
108  {
109  line[strlen (line) - 1] = '\0';
110  if (AF_INET == af)
111  {
112  if (inet_pton (af, line, &u->data.ipv4[u->count]))
113  {
114  u->count++;
115  u->data_len += sizeof(ipv4_address_t);
116  }
117  else
118  {
119  (void) fclose (p);
120  kwait (pid);
121  errno = EINVAL;
122  return -1;
123  }
124  }
125  else if (AF_INET6 == af)
126  {
127  if (inet_pton (af, line, &u->data.ipv6[u->count]))
128  {
129  u->count++;
130  u->data_len += sizeof(ipv6_address_t);
131  }
132  else
133  {
134  (void) fclose (p);
135  kwait (pid);
136  errno = EINVAL;
137  return -1;
138  }
139  }
140  }
141  }
142  (void) fclose (p);
143  waitpid (pid, &ret, 0);
144  if (! WIFEXITED (ret))
145  return -1;
146  if (4 == WEXITSTATUS (ret))
147  return -2; /* not for GNS */
148  if (5 == WEXITSTATUS (ret))
149  {
150  if (1 == retry)
151  return -2; /* no go -> service unavailable */
152  retry = 1;
153  system ("gnunet-arm -s");
154  goto query_gns; /* Try again */
155  }
156  if (3 == WEXITSTATUS (ret))
157  return -2; /* timeout -> service unavailable */
158  if ((2 == WEXITSTATUS (ret)) || (1 == WEXITSTATUS (ret)))
159  return -2; /* launch failure -> service unavailable */
160  return 0;
161 }
static int ret
Return value of the commandline.
Definition: gnunet-abd.c:81
static char * line
Desired phone line (string to be converted to a hash).
static struct GNUNET_PeerIdentity pid
Identity of the peer we transmit to / connect to.
static struct GNUNET_OS_Process * p
Helper process we started.
Definition: gnunet-uri.c:38
#define TIMEOUT
Definition: nss_gns_query.c:33
static void kwait(pid_t chld)
Definition: nss_gns_query.c:36
#define MAX_ENTRIES
Parts taken from nss-mdns.
Definition: nss_gns_query.h:29
const char * name
union userdata::@21 data
int data_len
Definition: nss_gns_query.h:46
ipv6_address_t ipv6[16]
Definition: nss_gns_query.h:50
ipv4_address_t ipv4[16]
Definition: nss_gns_query.h:49

References userdata::count, userdata::data, userdata::data_len, userdata::ipv4, userdata::ipv6, kwait(), line, MAX_ENTRIES, name, p, pid, ret, and TIMEOUT.

Here is the call graph for this function: