diff options
Diffstat (limited to 'resolv/nss_dns/dns-network.c')
| -rw-r--r-- | resolv/nss_dns/dns-network.c | 81 |
1 files changed, 26 insertions, 55 deletions
diff --git a/resolv/nss_dns/dns-network.c b/resolv/nss_dns/dns-network.c index 45f7f18057..135871093a 100644 --- a/resolv/nss_dns/dns-network.c +++ b/resolv/nss_dns/dns-network.c @@ -66,6 +66,9 @@ #include "nsswitch.h" #include <arpa/inet.h> +#include <arpa/nameser.h> +#include <out_buffer.h> +#include <resolv/resolv-internal.h> /* Maximum number of aliases we allow. */ #define MAX_NR_ALIASES 48 @@ -92,17 +95,10 @@ typedef union querybuf u_char buf[MAXPACKET]; } querybuf; -/* These functions are defined in res_comp.c. */ -#define NS_MAXCDNAME 255 /* maximum compressed domain name */ -extern int __ns_name_ntop (const u_char *, char *, size_t) __THROW; -extern int __ns_name_unpack (const u_char *, const u_char *, - const u_char *, u_char *, size_t) __THROW; - - /* Prototypes for local functions. */ static enum nss_status getanswer_r (const querybuf *answer, int anslen, - struct netent *result, char *buffer, - size_t buflen, int *errnop, int *h_errnop, + struct netent *result, struct out_buffer, + int *errnop, int *h_errnop, lookup_method net_i); @@ -140,7 +136,9 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result, ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; } - status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, + struct out_buffer outbuf; + out_buffer_init (&outbuf, buffer, buflen); + status = getanswer_r (net_buffer.buf, anslen, result, outbuf, errnop, herrnop, BYNAME); if (net_buffer.buf != orig_net_buffer) free (net_buffer.buf); @@ -217,7 +215,9 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result, ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; } - status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, + struct out_buffer outbuf; + out_buffer_init (&outbuf, buffer, buflen); + status = getanswer_r (net_buffer.buf, anslen, result, outbuf, errnop, herrnop, BYADDR); if (net_buffer.buf != orig_net_buffer) free (net_buffer.buf); @@ -237,7 +237,7 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result, static enum nss_status getanswer_r (const querybuf *answer, int anslen, struct netent *result, - char *buffer, size_t buflen, int *errnop, int *h_errnop, + struct out_buffer buf, int *errnop, int *h_errnop, lookup_method net_i) { /* @@ -254,16 +254,9 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, * | Additional | RRs holding additional information * +------------+ */ - struct net_data - { - char *aliases[MAX_NR_ALIASES]; - char linebuffer[0]; - } *net_data; - - uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct net_data); - buffer += pad; - if (__glibc_unlikely (buflen < sizeof (*net_data) + pad)) + char **aliases = out_buffer_get_array (&buf, char *, MAX_NR_ALIASES); + if (__glibc_unlikely (aliases == NULL)) { /* The buffer is too small. */ too_small: @@ -271,21 +264,15 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, *h_errnop = NETDB_INTERNAL; return NSS_STATUS_TRYAGAIN; } - buflen -= pad; + int alias_count = 0; - net_data = (struct net_data *) buffer; - int linebuflen = buflen - offsetof (struct net_data, linebuffer); - if (buflen - offsetof (struct net_data, linebuffer) != linebuflen) - linebuflen = INT_MAX; const unsigned char *end_of_message = &answer->buf[anslen]; const HEADER *header_pointer = &answer->hdr; /* #/records in the answer section. */ int answer_count = ntohs (header_pointer->ancount); /* #/entries in the question section. */ int question_count = ntohs (header_pointer->qdcount); - char *bp = net_data->linebuffer; const unsigned char *cp = &answer->buf[HFIXEDSZ]; - char **alias_pointer; int have_answer; u_char packtmp[NS_MAXCDNAME]; @@ -318,32 +305,17 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, cp += n + QFIXEDSZ; } - alias_pointer = result->n_aliases = &net_data->aliases[0]; - *alias_pointer = NULL; have_answer = 0; while (--answer_count >= 0 && cp < end_of_message) { - int n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen); int type, class; - - n = __ns_name_unpack (answer->buf, end_of_message, cp, - packtmp, sizeof packtmp); - if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1) - { - if (errno == EMSGSIZE) - goto too_small; - - n = -1; - } - - if (n > 0 && bp[0] == '.') - bp[0] = '\0'; - - if (n < 0 || res_dnok (bp) == 0) + int n = __ns_name_unpack (answer->buf, end_of_message, cp, + packtmp, sizeof packtmp); + if (n == -1) break; - cp += n; + cp += n; if (end_of_message - cp < 10) { __set_h_errno (NO_RECOVERY); @@ -365,7 +337,9 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, { n = __ns_name_unpack (answer->buf, end_of_message, cp, packtmp, sizeof packtmp); - if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1) + char *alias = NULL; + if (n != -1 + && (alias = __ns_name_ntop_buffer (&buf, packtmp)) == NULL) { if (errno == EMSGSIZE) goto too_small; @@ -373,7 +347,7 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, n = -1; } - if (n < 0 || !res_hnok (bp)) + if (n < 0 || !res_hnok (alias)) { /* XXX What does this mean? The original form from bind returns NULL. Incrementing cp has no effect in any case. @@ -382,12 +356,9 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, return NSS_STATUS_UNAVAIL; } cp += rdatalen; - if (alias_pointer + 2 < &net_data->aliases[MAX_NR_ALIASES]) + if (alias_count + 1 < MAX_NR_ALIASES) { - *alias_pointer++ = bp; - n = strlen (bp) + 1; - bp += n; - linebuflen -= n; + aliases[alias_count++] = alias; result->n_addrtype = class == C_IN ? AF_INET : AF_UNSPEC; ++have_answer; } @@ -399,7 +370,7 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, if (have_answer) { - *alias_pointer = NULL; + aliases[alias_count] = NULL; switch (net_i) { case BYADDR: |