From 6932f2282ba0578d6ca2f21eead920d6b78bc93c Mon Sep 17 00:00:00 2001 From: Waldemar Brodkorb Date: Sat, 2 Jan 2016 16:55:40 +0100 Subject: [PATCH] libc/inet: Unbreak gethostent() Although gethostent() is obsoleted, there is no reason to keep it broken. Fix two problems: * commit f65e66078b "resolver: switch to config parser" leave an extra break statement in case of GETHOSTENT in __read_etc_hosts_r. In result, output buffer wasn't initialized at all. * gethostent static buffer has insufficient size to store aliases, so __read_etc_hosts_r always returns ERANGE. Restore ALIAS_DIM define. Add test-case. Signed-off-by: Leonid Lisovskiy --- libc/inet/resolv.c | 13 +++++++------ test/inet/gethost.c | 40 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+), 6 deletions(-) create mode 100644 test/inet/gethost.c diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c index 25dc62dd3..eb663ac0f 100644 --- a/libc/inet/resolv.c +++ b/libc/inet/resolv.c @@ -337,6 +337,8 @@ Domain name in a message can be represented as either: #define MAX_RECURSE 5 #define MAXALIASES (4) +/* 1:ip + 1:full + MAX_ALIASES:aliases + 1:NULL */ +#define ALIAS_DIM (2 + MAXALIASES + 1) #define BUFSZ (80) /* one line */ #define NS_TYPE_ELT 0x40 /*%< EDNS0 extended label type */ @@ -1650,9 +1652,8 @@ int __read_etc_hosts_r( result_buf->h_aliases = tok+1; if (action == GETHOSTENT) { /* Return whatever the next entry happens to be. */ - break; - } - if (action == GET_HOSTS_BYADDR) { + ; + } else if (action == GET_HOSTS_BYADDR) { if (strcmp(name, *tok) != 0) continue; } else { /* GET_HOSTS_BYNAME */ @@ -2623,13 +2624,13 @@ struct hostent *gethostent(void) { static struct hostent hoste; static char *buf = NULL; - struct hostent *host; + struct hostent *host = NULL; #ifndef __UCLIBC_HAS_IPV6__ #define HOSTENT_BUFSZ (sizeof(struct in_addr) + sizeof(struct in_addr *) * 2 + \ - BUFSZ /*namebuffer*/ + 2 /* margin */) + sizeof(char *)*ALIAS_DIM + BUFSZ /*namebuffer*/ + 2 /* margin */) #else #define HOSTENT_BUFSZ (sizeof(struct in6_addr) + sizeof(struct in6_addr *) * 2 + \ - BUFSZ /*namebuffer*/ + 2 /* margin */) + sizeof(char *)*ALIAS_DIM + BUFSZ /*namebuffer*/ + 2 /* margin */) #endif /* __UCLIBC_HAS_IPV6__ */ __INIT_GETXX_BUF(HOSTENT_BUFSZ); diff --git a/test/inet/gethost.c b/test/inet/gethost.c new file mode 100644 index 000000000..77467e9e3 --- /dev/null +++ b/test/inet/gethost.c @@ -0,0 +1,40 @@ +#include +#include +#include +#include +#include +#include +#include + +int main(void) +{ + in_addr_t addr = inet_addr("127.0.0.1"); + struct hostent *hent; + + hent = gethostent(); + if (hent == NULL) { + printf("gethostent(%d):%s\n", errno, hstrerror(h_errno)); + exit(1); + } + + hent = gethostbyname("localhost"); + if (hent == NULL) { + printf("gethostbyname(%d):%s\n", errno, hstrerror(h_errno)); + exit(1); + } + + hent = gethostbyname2("localhost", AF_INET); + if (hent == NULL) { + printf("gethostbyname2(%d):%s\n", errno, hstrerror(h_errno)); + exit(1); + } + + hent = gethostbyaddr(&addr, sizeof(addr), AF_INET); + if (hent == NULL) { + printf("gethostbyaddr(%d):%s\n", errno, hstrerror(h_errno)); + exit(1); + } + + return 0; +} + -- 2.11.4.GIT