xref: /titanic_50/usr/src/cmd/ssh/libopenbsd-compat/common/fake-getaddrinfo.c (revision c77a61a72b5ecdc507d6cf104142edd371a16c84)
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 "includes.h"
13 #include "ssh.h"
14 
15 RCSID("$Id: fake-getaddrinfo.c,v 1.2 2001/02/09 01:55:36 djm Exp $");
16 
17 #pragma ident	"%Z%%M%	%I%	%E% SMI"
18 
19 #ifndef HAVE_GAI_STRERROR
20 char *gai_strerror(int ecode)
21 {
22 	switch (ecode) {
23 		case EAI_NODATA:
24 			return "no address associated with hostname.";
25 		case EAI_MEMORY:
26 			return "memory allocation failure.";
27 		default:
28 			return "unknown error.";
29 	}
30 }
31 #endif /* !HAVE_GAI_STRERROR */
32 
33 #ifndef HAVE_FREEADDRINFO
34 void freeaddrinfo(struct addrinfo *ai)
35 {
36 	struct addrinfo *next;
37 
38 	do {
39 		next = ai->ai_next;
40 		free(ai);
41 	} while (NULL != (ai = next));
42 }
43 #endif /* !HAVE_FREEADDRINFO */
44 
45 #ifndef HAVE_GETADDRINFO
46 static struct addrinfo *malloc_ai(int port, u_long addr)
47 {
48 	struct addrinfo *ai;
49 
50 	ai = malloc(sizeof(struct addrinfo) + sizeof(struct sockaddr_in));
51 	if (ai == NULL)
52 		return(NULL);
53 
54 	memset(ai, 0, sizeof(struct addrinfo) + sizeof(struct sockaddr_in));
55 
56 	ai->ai_addr = (struct sockaddr *)(ai + 1);
57 	/* XXX -- ssh doesn't use sa_len */
58 	ai->ai_addrlen = sizeof(struct sockaddr_in);
59 	ai->ai_addr->sa_family = ai->ai_family = AF_INET;
60 
61 	((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
62 	((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
63 
64 	return(ai);
65 }
66 
67 int getaddrinfo(const char *hostname, const char *servname,
68                 const struct addrinfo *hints, struct addrinfo **res)
69 {
70 	struct addrinfo *cur, *prev = NULL;
71 	struct hostent *hp;
72 	struct in_addr in;
73 	int i, port;
74 
75 	if (servname)
76 		port = htons(atoi(servname));
77 	else
78 		port = 0;
79 
80 	if (hints && hints->ai_flags & AI_PASSIVE) {
81 		if (NULL != (*res = malloc_ai(port, htonl(0x00000000))))
82 			return 0;
83 		else
84 			return EAI_MEMORY;
85 	}
86 
87 	if (!hostname) {
88 		if (NULL != (*res = malloc_ai(port, htonl(0x7f000001))))
89 			return 0;
90 		else
91 			return EAI_MEMORY;
92 	}
93 
94 	if (inet_aton(hostname, &in)) {
95 		if (NULL != (*res = malloc_ai(port, in.s_addr)))
96 			return 0;
97 		else
98 			return EAI_MEMORY;
99 	}
100 
101 	hp = gethostbyname(hostname);
102 	if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
103 		for (i = 0; hp->h_addr_list[i]; i++) {
104 			cur = malloc_ai(port, ((struct in_addr *)hp->h_addr_list[i])->s_addr);
105 			if (cur == NULL) {
106 				if (*res)
107 					freeaddrinfo(*res);
108 				return EAI_MEMORY;
109 			}
110 
111 			if (prev)
112 				prev->ai_next = cur;
113 			else
114 				*res = cur;
115 
116 			prev = cur;
117 		}
118 		return 0;
119 	}
120 
121 	return EAI_NODATA;
122 }
123 #endif /* !HAVE_GETADDRINFO */
124