From f65e66078b9f4d2d7f0fc336dee36e78fc467c0f Mon Sep 17 00:00:00 2001 From: Bernhard Reutner-Fischer Date: Mon, 1 Mar 2010 14:40:45 +0100 Subject: resolver: switch to config parser Signed-off-by: Bernhard Reutner-Fischer --- libc/inet/resolv.c | 255 +++++++++++++++++++++++++---------------------------- 1 file changed, 119 insertions(+), 136 deletions(-) (limited to 'libc') diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c index 6a9b80791..d45e5f8a0 100644 --- a/libc/inet/resolv.c +++ b/libc/inet/resolv.c @@ -124,6 +124,9 @@ * * 2008, 2009 Denys Vlasenko * Cleanups, fixes, readability, more cleanups and more fixes. + * + * March 2010 Bernhard Reutner-Fischer + * Switch to common config parser */ /* Nota bene: * The whole resolver code has several (severe) problems: @@ -314,6 +317,7 @@ Domain name in a message can be represented as either: #include #include #include +#include "internal/parse_config.h" /* poll() is not supported in kernel <= 2.0, therefore if __NR_poll is * not available, we assume an old Linux kernel is in use and we will @@ -329,11 +333,11 @@ Domain name in a message can be represented as either: #define IF_HAS_BOTH(...) #endif -#define MAX_RECURSE 5 -#define MAX_ALIASES 5 -/* 1:ip + 1:full + MAX_ALIASES:aliases + 1:NULL */ -#define ALIAS_DIM (2 + MAX_ALIASES + 1) +#define MAX_RECURSE 5 +#define MAXALIASES (6) +#define BUFSZ (80) /* one line */ +#define SBUFSIZE (BUFSZ + 1 + (sizeof(char *) * MAXALIASES)) #undef DEBUG /* #define DEBUG */ @@ -422,7 +426,8 @@ extern const struct sockaddr_in6 __local_nameserver attribute_hidden; #define MAXLEN_searchdomain 128 -/* function prototypes */ +/* prototypes for internal functions */ +extern void endhostent_unlocked(void) attribute_hidden; extern int __get_hosts_byname_r(const char *name, int type, struct hostent *result_buf, @@ -438,8 +443,8 @@ extern int __get_hosts_byaddr_r(const char *addr, size_t buflen, struct hostent **result, int *h_errnop) attribute_hidden; -extern FILE *__open_etc_hosts(void) attribute_hidden; -extern int __read_etc_hosts_r(FILE *fp, +extern parser_t *__open_etc_hosts(void) attribute_hidden; +extern int __read_etc_hosts_r(parser_t *parser, const char *name, int type, enum etc_hosts_action action, @@ -1571,19 +1576,19 @@ int attribute_hidden __dns_lookup(const char *name, #ifdef L_read_etc_hosts_r -FILE * __open_etc_hosts(void) +parser_t * __open_etc_hosts(void) { - FILE * fp; - if ((fp = fopen("/etc/hosts", "r")) == NULL) { + parser_t * parser; + if ((parser = config_open("/etc/hosts")) == NULL) { #ifdef FALLBACK_TO_CONFIG_RESOLVCONF - fp = fopen("/etc/config/hosts", "r"); + parser = config_open("/etc/config/hosts"); #endif } - return fp; + return parser; } int attribute_hidden __read_etc_hosts_r( - FILE * fp, + parser_t * parser, const char *name, int type, enum etc_hosts_action action, @@ -1592,112 +1597,90 @@ int attribute_hidden __read_etc_hosts_r( struct hostent **result, int *h_errnop) { - struct in_addr **addr_list = NULL; - struct in_addr *in = NULL; - char *cp, **alias; - int aliases, i, ret = HOST_NOT_FOUND; - - *h_errnop = NETDB_INTERNAL; - - /* make sure pointer is aligned */ - i = ALIGN_BUFFER_OFFSET(buf); - buf += i; - buflen -= i; - /* Layout in buf: - * char *alias[ALIAS_DIM]; - * struct in[6]_addr* addr_list[2]; - * struct in[6]_addr* in; - * char line_buffer[80+]; - */ -#define in6 ((struct in6_addr *)in) - alias = (char **)buf; - buf += sizeof(char **) * ALIAS_DIM; - buflen -= sizeof(char **) * ALIAS_DIM; - if ((ssize_t)buflen < 0) - return ERANGE; - if (action != GETHOSTENT) { - addr_list = (struct in_addr**)buf; - buf += sizeof(*addr_list) * 2; - buflen -= sizeof(*addr_list) * 2; - in = (struct in_addr*)buf; -#ifndef __UCLIBC_HAS_IPV6__ - buf += sizeof(*in); - buflen -= sizeof(*in); + char **alias, *cp = NULL; + char **host_aliases; + char **tok = NULL; + struct in_addr *h_addr0 = NULL; +#define ALIASOFF (sizeof(*host_aliases) * MAXALIASES + 2 * sizeof(char*)) + const size_t aliaslen = ALIASOFF + +#ifdef __UCLIBC_HAS_IPV6__ + sizeof(struct in6_addr) #else - buf += sizeof(*in6); - buflen -= sizeof(*in6); + sizeof(struct in_addr) #endif - if ((ssize_t)buflen < 80) - return ERANGE; + ; + int ret = HOST_NOT_FOUND; - fp = __open_etc_hosts(); - if (fp == NULL) { - *result = NULL; - return errno; - } - addr_list[0] = in; - addr_list[1] = NULL; + *h_errnop = NETDB_INTERNAL; + if (buflen < aliaslen + || (buflen - aliaslen) < BUFSZ + 1) + return ERANGE; + if (parser == NULL) + parser = __open_etc_hosts(); + if (parser == NULL) { + *result = NULL; + return errno; } - + /* Layout in buf: + * char **alias for MAXALIAS aliases + * char **h_addr_list[1] = {*in[6]_addr, NULL} + * struct in[6]_addr + * char line_buffer[BUFSZ+]; + */ + parser->data = buf; + parser->data_len = aliaslen; + parser->line_len = buflen - aliaslen; *h_errnop = HOST_NOT_FOUND; - while (fgets(buf, buflen, fp)) { - *strchrnul(buf, '#') = '\0'; - DPRINTF("Looking at: %s\n", buf); - aliases = 0; - - cp = buf; - while (*cp) { - while (*cp && isspace(*cp)) + /* [[:space:]][] */ + while (config_read(parser, &tok, 2, 2, "# \t", PARSE_NORMAL)) { + result_buf->h_aliases = alias = host_aliases = tok+1; + cp = *alias; + while (cp && *cp) { + if (alias < &host_aliases[MAXALIASES - 1]) + *alias++ = cp; + cp = strpbrk(cp, " \t"); + if (cp != NULL) *cp++ = '\0'; - if (!*cp) - break; - if (aliases < (2 + MAX_ALIASES)) - alias[aliases++] = cp; - while (*cp && !isspace(*cp)) - cp++; } - alias[aliases] = NULL; - - if (aliases < 2) - continue; /* syntax error really */ - + *alias = NULL; if (action == GETHOSTENT) { /* Return whatever the next entry happens to be. */ break; } + result_buf->h_name = *(result_buf->h_aliases++); if (action == GET_HOSTS_BYADDR) { - if (strcmp(name, alias[0]) != 0) + if (strcmp(name, result_buf->h_name) != 0) continue; - } else { - /* GET_HOSTS_BYNAME */ - for (i = 1; i < aliases; i++) - if (strcasecmp(name, alias[i]) == 0) + } else { /* GET_HOSTS_BYNAME */ + alias = result_buf->h_aliases; + while ((cp = *(alias++))) + if (strcasecmp(name, cp) == 0) goto found; continue; - found: ; } - +found: + result_buf->h_addr_list = (char**)(buf + ALIASOFF); + *(result_buf->h_addr_list + 1) = '\0'; + h_addr0 = (struct in_addr*)(buf + ALIASOFF + 2 * sizeof (char*)); + result_buf->h_addr = (char*)h_addr0; if (0) /* nothing */; #ifdef __UCLIBC_HAS_IPV4__ - else if (type == AF_INET && inet_pton(AF_INET, alias[0], in) > 0) { + else if (type == AF_INET + && inet_pton(AF_INET, *tok, h_addr0) > 0) { DPRINTF("Found INET\n"); result_buf->h_addrtype = AF_INET; - result_buf->h_length = sizeof(*in); - result_buf->h_name = alias[1]; - result_buf->h_addr_list = (char**) addr_list; - result_buf->h_aliases = alias + 2; + result_buf->h_length = sizeof(struct in_addr); *result = result_buf; ret = NETDB_SUCCESS; } #endif #ifdef __UCLIBC_HAS_IPV6__ - else if (type == AF_INET6 && inet_pton(AF_INET6, alias[0], in6) > 0) { +#define in6 ((struct in6_addr *)buf) + else if (type == AF_INET6 + && inet_pton(AF_INET6, *tok, h_addr0) > 0) { DPRINTF("Found INET6\n"); result_buf->h_addrtype = AF_INET6; - result_buf->h_length = sizeof(*in6); - result_buf->h_name = alias[1]; - result_buf->h_addr_list = (char**) addr_list; - result_buf->h_aliases = alias + 2; + result_buf->h_length = sizeof(struct in6_addr); *result = result_buf; ret = NETDB_SUCCESS; } @@ -1709,7 +1692,7 @@ int attribute_hidden __read_etc_hosts_r( * host * If looking for an IPv6 addr, don't bail when we got the IPv4 */ - DPRINTF("Error: Found host but diff network type\n"); + DPRINTF("Error: Found host but different address family\n"); /* NB: gethostbyname2_r depends on this feature * to avoid looking for IPv6 addr of "localhost" etc */ ret = TRY_AGAIN; @@ -1718,7 +1701,7 @@ int attribute_hidden __read_etc_hosts_r( break; } if (action != GETHOSTENT) - fclose(fp); + config_close(parser); return ret; #undef in6 } @@ -1795,7 +1778,7 @@ int getnameinfo(const struct sockaddr *sa, { int serrno = errno; unsigned ok; - struct hostent *h = NULL; + struct hostent *hoste = NULL; char domain[256]; if (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV|NI_NOFQDN|NI_NAMEREQD|NI_DGRAM)) @@ -1832,31 +1815,31 @@ int getnameinfo(const struct sockaddr *sa, if (0) /* nothing */; #ifdef __UCLIBC_HAS_IPV6__ else if (sa->sa_family == AF_INET6) - h = gethostbyaddr((const void *) + hoste = gethostbyaddr((const void *) &(((const struct sockaddr_in6 *) sa)->sin6_addr), sizeof(struct in6_addr), AF_INET6); #endif #ifdef __UCLIBC_HAS_IPV4__ else - h = gethostbyaddr((const void *) + hoste = gethostbyaddr((const void *) &(((const struct sockaddr_in *)sa)->sin_addr), sizeof(struct in_addr), AF_INET); #endif - if (h) { + if (hoste) { char *c; #undef min #define min(x,y) (((x) > (y)) ? (y) : (x)) if ((flags & NI_NOFQDN) && (getdomainname(domain, sizeof(domain)) == 0) - && (c = strstr(h->h_name, domain)) != NULL - && (c != h->h_name) && (*(--c) == '.') + && (c = strstr(hoste->h_name, domain)) != NULL + && (c != hoste->h_name) && (*(--c) == '.') ) { - strncpy(host, h->h_name, - min(hostlen, (size_t) (c - h->h_name))); - host[min(hostlen - 1, (size_t) (c - h->h_name))] = '\0'; + strncpy(host, hoste->h_name, + min(hostlen, (size_t) (c - hoste->h_name))); + host[min(hostlen - 1, (size_t) (c - hoste->h_name))] = '\0'; } else { - strncpy(host, h->h_name, hostlen); + strncpy(host, hoste->h_name, hostlen); } ok = 1; #undef min @@ -2424,8 +2407,6 @@ int gethostbyaddr_r(const void *addr, socklen_t addrlen, */ #define in6 ((struct in6_addr *)in) alias = (char **)buf; - buf += sizeof(*alias) * ALIAS_DIM; - buflen -= sizeof(*alias) * ALIAS_DIM; addr_list = (struct in_addr**)buf; buf += sizeof(*addr_list) * 2; buflen -= sizeof(*addr_list) * 2; @@ -2524,24 +2505,29 @@ link_warning(gethostbyaddr_r, "gethostbyaddr_r is obsolescent, use getaddrinfo() __UCLIBC_MUTEX_STATIC(mylock, PTHREAD_MUTEX_INITIALIZER); -static smallint __stay_open; -static FILE * __gethostent_fp; +static parser_t *hostp = NULL; +static smallint host_stayopen; +void endhostent_unlocked(void) +{ + if (hostp) { + config_close(hostp); + hostp = NULL; + } + host_stayopen = 0; +} void endhostent(void) { __UCLIBC_MUTEX_LOCK(mylock); - __stay_open = 0; - if (__gethostent_fp) { - fclose(__gethostent_fp); - __gethostent_fp = NULL; - } + endhostent_unlocked(); __UCLIBC_MUTEX_UNLOCK(mylock); } void sethostent(int stay_open) { __UCLIBC_MUTEX_LOCK(mylock); - __stay_open = (stay_open != 0); + if (stay_open) + host_stayopen = 1; __UCLIBC_MUTEX_UNLOCK(mylock); } @@ -2551,21 +2537,19 @@ int gethostent_r(struct hostent *result_buf, char *buf, size_t buflen, int ret; __UCLIBC_MUTEX_LOCK(mylock); - if (__gethostent_fp == NULL) { - __gethostent_fp = __open_etc_hosts(); - if (__gethostent_fp == NULL) { + if (hostp == NULL) { + hostp = __open_etc_hosts(); + if (hostp == NULL) { *result = NULL; ret = TRY_AGAIN; goto DONE; } } - ret = __read_etc_hosts_r(__gethostent_fp, NULL, AF_INET, GETHOSTENT, + ret = __read_etc_hosts_r(hostp, NULL, AF_INET, GETHOSTENT, result_buf, buf, buflen, result, h_errnop); - if (__stay_open == 0) { - fclose(__gethostent_fp); - __gethostent_fp = NULL; - } + if (!host_stayopen) + endhostent_unlocked(); DONE: __UCLIBC_MUTEX_UNLOCK(mylock); return ret; @@ -2578,18 +2562,17 @@ libc_hidden_def(gethostent_r) struct hostent *gethostent(void) { - static struct hostent h; + static struct hostent hoste; static char buf[ #ifndef __UCLIBC_HAS_IPV6__ sizeof(struct in_addr) + sizeof(struct in_addr *) * 2 + #else sizeof(struct in6_addr) + sizeof(struct in6_addr *) * 2 + #endif /* __UCLIBC_HAS_IPV6__ */ - sizeof(char *) * ALIAS_DIM + - 80 /*namebuffer*/ + 2 /* margin */]; + BUFSZ /*namebuffer*/ + 2 /* margin */]; struct hostent *host; - gethostent_r(&h, buf, sizeof(buf), &host, &h_errno); + gethostent_r(&hoste, buf, sizeof(buf), &host, &h_errno); return host; } #endif @@ -2602,13 +2585,13 @@ struct hostent *gethostbyname2(const char *name, int family) #ifndef __UCLIBC_HAS_IPV6__ return family == AF_INET ? gethostbyname(name) : (struct hostent*)NULL; #else - static struct hostent h; + static struct hostent hoste; static char buf[sizeof(struct in6_addr) + sizeof(struct in6_addr *) * 2 + - sizeof(char *)*ALIAS_DIM + 384/*namebuffer*/ + 32/* margin */]; + /*sizeof(char *)*ALIAS_DIM +*/ 384/*namebuffer*/ + 32/* margin */]; struct hostent *hp; - gethostbyname2_r(name, family, &h, buf, sizeof(buf), &hp, &h_errno); + gethostbyname2_r(name, family, &hoste, buf, sizeof(buf), &hp, &h_errno); return hp; #endif } @@ -2621,13 +2604,13 @@ libc_hidden_def(gethostbyname2) struct hostent *gethostbyname(const char *name) { #ifndef __UCLIBC_HAS_IPV6__ - static struct hostent h; + static struct hostent hoste; static char buf[sizeof(struct in_addr) + sizeof(struct in_addr *) * 2 + - sizeof(char *)*ALIAS_DIM + 384/*namebuffer*/ + 32/* margin */]; + /*sizeof(char *)*ALIAS_DIM +*/ 384/*namebuffer*/ + 32/* margin */]; struct hostent *hp; - gethostbyname_r(name, &h, buf, sizeof(buf), &hp, &h_errno); + gethostbyname_r(name, &hoste, buf, sizeof(buf), &hp, &h_errno); return hp; #else return gethostbyname2(name, AF_INET); @@ -2642,17 +2625,17 @@ link_warning(gethostbyname, "gethostbyname is obsolescent, use getnameinfo() ins struct hostent *gethostbyaddr(const void *addr, socklen_t len, int type) { - static struct hostent h; + static struct hostent hoste; static char buf[ #ifndef __UCLIBC_HAS_IPV6__ sizeof(struct in_addr) + sizeof(struct in_addr *)*2 + #else sizeof(struct in6_addr) + sizeof(struct in6_addr *)*2 + #endif /* __UCLIBC_HAS_IPV6__ */ - sizeof(char *)*ALIAS_DIM + 384 /*namebuffer*/ + 32 /* margin */]; + /*sizeof(char *)*ALIAS_DIM +*/ 384 /*namebuffer*/ + 32 /* margin */]; struct hostent *hp; - gethostbyaddr_r(addr, len, type, &h, buf, sizeof(buf), &hp, &h_errno); + gethostbyaddr_r(addr, len, type, &hoste, buf, sizeof(buf), &hp, &h_errno); return hp; } libc_hidden_def(gethostbyaddr) @@ -3052,7 +3035,7 @@ void res_close(void) which can have an alias. */ struct __res_state _res __attribute__((section (".bss"))); struct __res_state *__resp = &_res; -#else //__UCLIBC_HAS_THREADS__ +#else /* __UCLIBC_HAS_THREADS__ */ struct __res_state _res __attribute__((section (".bss"))) attribute_hidden; # if defined __UCLIBC_HAS_TLS__ -- cgit v1.2.3