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Diffstat (limited to 'lib/util/inet_ntop.c')
| -rw-r--r-- | lib/util/inet_ntop.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/lib/util/inet_ntop.c b/lib/util/inet_ntop.c new file mode 100644 index 0000000..e456d6e --- /dev/null +++ b/lib/util/inet_ntop.c @@ -0,0 +1,229 @@ +/* $OpenBSD: inet_ntop.c,v 1.9 2014/02/05 14:20:43 millert Exp $ */ + +/* + * SPDX-License-Identifier: ISC + * + * Copyright (c) 1996 by Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS + * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE + * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL + * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR + * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS + * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + */ + +#include <config.h> + +#if !defined(HAVE_INET_NTOP) + +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <arpa/nameser.h> +#include <string.h> +#include <errno.h> +#include <stdio.h> + +#include <sudo_compat.h> + +#ifndef EAFNOSUPPORT +# define EAFNOSUPPORT EINVAL +#endif + +#ifndef NS_IN6ADDRSZ +# ifdef IN6ADDRSZ +# define NS_IN6ADDRSZ IN6ADDRSZ +# else +# define NS_IN6ADDRSZ 16 +# endif +#endif +#ifndef NS_INT16SZ +# ifdef INT16SZ +# define NS_INT16SZ INT16SZ +# else +# define NS_INT16SZ 2 +# endif +#endif + +/* + * WARNING: Don't even consider trying to compile this on a system where + * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX. + */ + +/* const char * + * inet_ntop4(src, dst, size) + * format an IPv4 address, more or less like inet_ntoa() + * return: + * `dst' (as a const) + * notes: + * (1) uses no statics + * (2) takes a unsigned char* not an in_addr as input + * author: + * Paul Vixie, 1996. + */ +static const char * +inet_ntop4(const unsigned char * restrict src, char * restrict dst, socklen_t size) +{ + const char fmt[] = "%u.%u.%u.%u"; + int len; + + len = snprintf(dst, size, fmt, src[0], src[1], src[2], src[3]); + if (len < 0 || (socklen_t)len >= size) { + errno = ENOSPC; + return (NULL); + } + return (dst); +} + +#ifdef HAVE_STRUCT_IN6_ADDR +/* const char * + * inet_ntop6(src, dst, size) + * convert IPv6 binary address into presentation (printable) format + * author: + * Paul Vixie, 1996. + */ +static const char * +inet_ntop6(const unsigned char * restrict src, char * restrict dst, socklen_t size) +{ + /* + * Note that int32_t and int16_t need only be "at least" large enough + * to contain a value of the specified size. On some systems, like + * Crays, there is no such thing as an integer variable with 16 bits. + * Keep this in mind if you think this function should have been coded + * to use pointer overlays. All the world's not a VAX. + */ + char *cp, *ep; + struct { int base, len; } best, cur; + unsigned int words[NS_IN6ADDRSZ / NS_INT16SZ]; + int i; + int advance; + + /* + * Preprocess: + * Copy the input (bytewise) array into a wordwise array. + * Find the longest run of 0x00's in src[] for :: shorthanding. + */ + memset(words, 0, sizeof(words)); + for (i = 0; i < NS_IN6ADDRSZ; i++) + words[i / 2] |= (src[i] << ((1 - (i & 1)) << 3)); + best.base = -1; + best.len = 0; + cur.base = -1; + cur.len = 0; + for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) { + if (words[i] == 0) { + if (cur.base == -1) + cur.base = i, cur.len = 1; + else + cur.len++; + } else { + if (cur.base != -1) { + if (best.base == -1 || cur.len > best.len) + best = cur; + cur.base = -1; + } + } + } + if (cur.base != -1) { + if (best.base == -1 || cur.len > best.len) + best = cur; + } + if (best.base != -1 && best.len < 2) + best.base = -1; + + /* + * Format the result. + */ + cp = dst; + ep = dst + size; + for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ) && cp < ep; i++) { + /* Are we inside the best run of 0x00's? */ + if (best.base != -1 && i >= best.base && + i < (best.base + best.len)) { + if (i == best.base) { + if (cp + 1 >= ep) { + errno = ENOSPC; + return (NULL); + } + *cp++ = ':'; + } + continue; + } + /* Are we following an initial run of 0x00s or any real hex? */ + if (i != 0) { + if (cp + 1 >= ep) { + errno = ENOSPC; + return (NULL); + } + *cp++ = ':'; + } + /* Is this address an encapsulated IPv4? */ + if (i == 6 && best.base == 0 && + (best.len == 6 || + (best.len == 7 && words[7] != 0x0001) || + (best.len == 5 && words[5] == 0xffff))) { + if (!inet_ntop4(src + 12, cp, (socklen_t)(ep - cp))) + return (NULL); + cp += strlen(cp); + break; + } + advance = snprintf(cp, (size_t)(ep - cp), "%x", words[i]); + if (advance <= 0 || advance >= ep - cp) { + errno = ENOSPC; + return (NULL); + } + cp += advance; + } + /* Was it a trailing run of 0x00's? */ + if (best.base != -1 && + (best.base + best.len) == (NS_IN6ADDRSZ / NS_INT16SZ)) { + if (cp + 1 >= ep) { + errno = ENOSPC; + return (NULL); + } + *cp++ = ':'; + } + if (cp + 1 >= ep) { + errno = ENOSPC; + return (NULL); + } + *cp++ = '\0'; + + return (dst); +} +#endif /* HAVE_STRUCT_IN6_ADDR */ + +/* const char * + * inet_ntop(af, src, dst, size) + * convert a network format address to presentation format. + * return: + * pointer to presentation format address (`dst'), or NULL (see errno). + * author: + * Paul Vixie, 1996. + */ +const char * +sudo_inet_ntop(int af, const void * restrict src, char * restrict dst, socklen_t size) +{ + switch (af) { + case AF_INET: + return (inet_ntop4(src, dst, size)); +#ifdef HAVE_STRUCT_IN6_ADDR + case AF_INET6: + return (inet_ntop6(src, dst, size)); +#endif + default: + errno = EAFNOSUPPORT; + return (NULL); + } + /* NOTREACHED */ +} + +#endif /* !HAVE_INET_NTOP */ |