release/src/router/tinc/src/fake-getaddrinfo.c

   1 /*
   2  * fake library for ssh
   3  *
   4  * This file includes getaddrinfo(), freeaddrinfo() and gai_strerror().
   5  * These funtions are defined in rfc2133.
   6  *
   7  * But these functions are not implemented correctly. The minimum subset
   8  * is implemented for ssh use only. For exapmle, this routine assumes
   9  * that ai_family is AF_INET. Don't use it for another purpose.
  10  */
  11
  12 #include "system.h"
  13
  14 #include "ipv4.h"
  15 #include "ipv6.h"
  16 #include "fake-getaddrinfo.h"
  17 #include "xalloc.h"
  18
  19
  20 #if !HAVE_DECL_GAI_STRERROR
  21 char *gai_strerror(int ecode) {
  22         switch (ecode) {
  23                 case EAI_NODATA:
  24                         return "No address associated with hostname";
  25                 case EAI_MEMORY:
  26                         return "Memory allocation failure";
  27                 case EAI_FAMILY:
  28                         return "Address family not supported";
  29                 default:
  30                         return "Unknown error";
  31         }
  32 }
  33 #endif /* !HAVE_GAI_STRERROR */
  34
  35 #if !HAVE_DECL_FREEADDRINFO
  36 void freeaddrinfo(struct addrinfo *ai) {
  37         struct addrinfo *next;
  38
  39         while(ai) {
  40                 next = ai->ai_next;
  41                 free(ai);
  42                 ai = next;
  43         }
  44 }
  45 #endif /* !HAVE_FREEADDRINFO */
  46
  47 #if !HAVE_DECL_GETADDRINFO
  48 static struct addrinfo *malloc_ai(uint16_t port, uint32_t addr) {
  49         struct addrinfo *ai;
  50
  51         ai = xzalloc(sizeof(struct addrinfo) + sizeof(struct sockaddr_in));
  52
  53         ai->ai_addr = (struct sockaddr *)(ai + 1);
  54         ai->ai_addrlen = sizeof(struct sockaddr_in);
  55         ai->ai_addr->sa_family = ai->ai_family = AF_INET;
  56
  57         ((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
  58         ((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
  59
  60         return ai;
  61 }
  62
  63 int getaddrinfo(const char *hostname, const char *servname, const struct addrinfo *hints, struct addrinfo **res) {
  64         struct addrinfo *prev = NULL;
  65         struct hostent *hp;
  66         struct in_addr in = {0};
  67         int i;
  68         uint16_t port = 0;
  69
  70         if(hints && hints->ai_family != AF_INET && hints->ai_family != AF_UNSPEC)
  71                 return EAI_FAMILY;
  72
  73         if (servname)
  74                 port = htons(atoi(servname));
  75
  76         if (hints && hints->ai_flags & AI_PASSIVE) {
  77                 *res = malloc_ai(port, htonl(0x00000000));
  78                 return 0;
  79         }
  80
  81         if (!hostname) {
  82                 *res = malloc_ai(port, htonl(0x7f000001));
  83                 return 0;
  84         }
  85
  86         hp = gethostbyname(hostname);
  87
  88         if(!hp || !hp->h_addr_list || !hp->h_addr_list[0])
  89                 return EAI_NODATA;
  90
  91         for (i = 0; hp->h_addr_list[i]; i++) {
  92                 *res = malloc_ai(port, ((struct in_addr *)hp->h_addr_list[i])->s_addr);
  93
  94                 if(prev)
  95                         prev->ai_next = *res;
  96
  97                 prev = *res;
  98         }
  99
 100         return 0;
 101 }
 102 #endif /* !HAVE_GETADDRINFO */