diff options
Diffstat (limited to 'resolv/res_send.c')
-rw-r--r-- | resolv/res_send.c | 264 |
1 files changed, 127 insertions, 137 deletions
diff --git a/resolv/res_send.c b/resolv/res_send.c index ca3e630868..18e54dbcda 100644 --- a/resolv/res_send.c +++ b/resolv/res_send.c @@ -73,6 +73,7 @@ static const char rcsid[] = "$BINDId: res_send.c,v 8.38 2000/03/30 20:16:51 vixi * Send query to name server and wait for reply. */ +#include <assert.h> #include <sys/types.h> #include <sys/param.h> #include <sys/time.h> @@ -808,7 +809,7 @@ send_dg(res_state statp, int ptimeout; struct sockaddr_in6 from; static int socket_pf = 0; - int fromlen, resplen, seconds, n, s; + int fromlen, resplen, seconds, n; if (EXT(statp).nssocks[ns] == -1) { /* only try IPv6 if IPv6 NS and if not failed before */ @@ -854,7 +855,7 @@ send_dg(res_state statp, Dprint(statp->options & RES_DEBUG, (stdout, ";; new DG socket\n")) } - s = EXT(statp).nssocks[ns]; + /* * Compute time for the total operation. */ @@ -867,13 +868,25 @@ send_dg(res_state statp, evConsTime(&timeout, seconds, 0); evAddTime(&finish, &now, &timeout); int need_recompute = 0; - resend: + int nwritten = 0; + pfd[0].fd = EXT(statp).nssocks[ns]; + pfd[0].events = POLLOUT; + wait: + if (need_recompute) { + evNowTime(&now); + if (evCmpTime(finish, now) <= 0) { + Perror(statp, stderr, "select", errno); + res_nclose(statp); + return (0); + } + evSubTime(&timeout, &finish, &now); + } /* Convert struct timespec in milliseconds. */ ptimeout = timeout.tv_sec * 1000 + timeout.tv_nsec / 1000000; - pfd[0].fd = s; - pfd[0].events = POLLOUT; - n = __poll (pfd, 1, 0); + n = 0; + if (nwritten == 0) + n = __poll (pfd, 1, 0); if (__builtin_expect (n == 0, 0)) { n = __poll (pfd, 1, ptimeout); need_recompute = 1; @@ -890,7 +903,7 @@ send_dg(res_state statp, evNowTime(&now); if (evCmpTime(finish, now) > 0) { evSubTime(&timeout, &finish, &now); - goto resend; + goto wait; } } Perror(statp, stderr, "select", errno); @@ -898,149 +911,126 @@ send_dg(res_state statp, return (0); } __set_errno (0); - if (send(s, (char*)buf, buflen, 0) != buflen) { - if (errno == EINTR || errno == EAGAIN) - goto recompute_resend; - Perror(statp, stderr, "send", errno); - res_nclose(statp); - return (0); - } - - wait: - if (need_recompute) { - evNowTime(&now); - if (evCmpTime(finish, now) <= 0) { - err_return: - Perror(statp, stderr, "select", errno); + if (pfd[0].revents & POLLOUT) { + if (send(pfd[0].fd, (char*)buf, buflen, 0) != buflen) { + if (errno == EINTR || errno == EAGAIN) + goto recompute_resend; + Perror(statp, stderr, "send", errno); res_nclose(statp); return (0); } - evSubTime(&timeout, &finish, &now); - } - /* Convert struct timespec in milliseconds. */ - ptimeout = timeout.tv_sec * 1000 + timeout.tv_nsec / 1000000; + pfd[0].events = POLLIN; + ++nwritten; + goto wait; + } else { + assert(pfd[0].revents & POLLIN); - pfd[0].events = POLLIN; - n = __poll (pfd, 1, ptimeout); - if (n == 0) { - Dprint(statp->options & RES_DEBUG, (stdout, - ";; timeout receiving\n")); + fromlen = sizeof(struct sockaddr_in6); + if (anssiz < MAXPACKET + && anscp + && (ioctl (pfd[0].fd, FIONREAD, &resplen) < 0 + || anssiz < resplen)) { + ans = malloc (MAXPACKET); + if (ans == NULL) + ans = *ansp; + else { + anssiz = MAXPACKET; + *anssizp = MAXPACKET; + *ansp = ans; + *anscp = ans; + anhp = (HEADER *) ans; + } + } + resplen = recvfrom(pfd[0].fd, (char*)ans, anssiz,0, + (struct sockaddr *)&from, &fromlen); + if (resplen <= 0) { + if (errno == EINTR || errno == EAGAIN) { + need_recompute = 1; + goto wait; + } + Perror(statp, stderr, "recvfrom", errno); + res_nclose(statp); + return (0); + } *gotsomewhere = 1; - return (0); - } - if (n < 0) { - if (errno == EINTR) { - need_recompute = 1; + if (resplen < HFIXEDSZ) { + /* + * Undersized message. + */ + Dprint(statp->options & RES_DEBUG, + (stdout, ";; undersized: %d\n", + resplen)); + *terrno = EMSGSIZE; + res_nclose(statp); + return (0); + } + if (hp->id != anhp->id) { + /* + * response from old query, ignore it. + * XXX - potential security hazard could + * be detected here. + */ + DprintQ((statp->options & RES_DEBUG) || + (statp->pfcode & RES_PRF_REPLY), + (stdout, ";; old answer:\n"), + ans, (resplen > anssiz) ? anssiz : resplen); goto wait; } - goto err_return; - } - __set_errno (0); - fromlen = sizeof(struct sockaddr_in6); - if (anssiz < MAXPACKET - && anscp - && (ioctl (s, FIONREAD, &resplen) < 0 - || anssiz < resplen)) { - ans = malloc (MAXPACKET); - if (ans == NULL) - ans = *ansp; - else { - anssiz = MAXPACKET; - *anssizp = MAXPACKET; - *ansp = ans; - *anscp = ans; - anhp = (HEADER *) ans; + if (!(statp->options & RES_INSECURE1) && + !res_ourserver_p(statp, &from)) { + /* + * response from wrong server? ignore it. + * XXX - potential security hazard could + * be detected here. + */ + DprintQ((statp->options & RES_DEBUG) || + (statp->pfcode & RES_PRF_REPLY), + (stdout, ";; not our server:\n"), + ans, (resplen > anssiz) ? anssiz : resplen); + goto wait; } - } - resplen = recvfrom(s, (char*)ans, anssiz,0, - (struct sockaddr *)&from, &fromlen); - if (resplen <= 0) { - if (errno == EINTR || errno == EAGAIN) { - need_recompute = 1; + if (!(statp->options & RES_INSECURE2) && + !res_queriesmatch(buf, buf + buflen, + ans, ans + anssiz)) { + /* + * response contains wrong query? ignore it. + * XXX - potential security hazard could + * be detected here. + */ + DprintQ((statp->options & RES_DEBUG) || + (statp->pfcode & RES_PRF_REPLY), + (stdout, ";; wrong query name:\n"), + ans, (resplen > anssiz) ? anssiz : resplen); goto wait; } - Perror(statp, stderr, "recvfrom", errno); - res_nclose(statp); - return (0); - } - *gotsomewhere = 1; - if (resplen < HFIXEDSZ) { - /* - * Undersized message. - */ - Dprint(statp->options & RES_DEBUG, - (stdout, ";; undersized: %d\n", - resplen)); - *terrno = EMSGSIZE; - res_nclose(statp); - return (0); - } - if (hp->id != anhp->id) { - /* - * response from old query, ignore it. - * XXX - potential security hazard could - * be detected here. - */ - DprintQ((statp->options & RES_DEBUG) || - (statp->pfcode & RES_PRF_REPLY), - (stdout, ";; old answer:\n"), - ans, (resplen > anssiz) ? anssiz : resplen); - goto wait; - } - if (!(statp->options & RES_INSECURE1) && - !res_ourserver_p(statp, &from)) { - /* - * response from wrong server? ignore it. - * XXX - potential security hazard could - * be detected here. - */ - DprintQ((statp->options & RES_DEBUG) || - (statp->pfcode & RES_PRF_REPLY), - (stdout, ";; not our server:\n"), - ans, (resplen > anssiz) ? anssiz : resplen); - goto wait; - } - if (!(statp->options & RES_INSECURE2) && - !res_queriesmatch(buf, buf + buflen, - ans, ans + anssiz)) { - /* - * response contains wrong query? ignore it. - * XXX - potential security hazard could - * be detected here. - */ - DprintQ((statp->options & RES_DEBUG) || - (statp->pfcode & RES_PRF_REPLY), - (stdout, ";; wrong query name:\n"), - ans, (resplen > anssiz) ? anssiz : resplen); - goto wait; - } - if (anhp->rcode == SERVFAIL || - anhp->rcode == NOTIMP || - anhp->rcode == REFUSED) { - DprintQ(statp->options & RES_DEBUG, - (stdout, "server rejected query:\n"), - ans, (resplen > anssiz) ? anssiz : resplen); - res_nclose(statp); - /* don't retry if called from dig */ - if (!statp->pfcode) - return (0); - } - if (!(statp->options & RES_IGNTC) && anhp->tc) { + if (anhp->rcode == SERVFAIL || + anhp->rcode == NOTIMP || + anhp->rcode == REFUSED) { + DprintQ(statp->options & RES_DEBUG, + (stdout, "server rejected query:\n"), + ans, (resplen > anssiz) ? anssiz : resplen); + res_nclose(statp); + /* don't retry if called from dig */ + if (!statp->pfcode) + return (0); + } + if (!(statp->options & RES_IGNTC) && anhp->tc) { + /* + * To get the rest of answer, + * use TCP with same server. + */ + Dprint(statp->options & RES_DEBUG, + (stdout, ";; truncated answer\n")); + *v_circuit = 1; + res_nclose(statp); + return (1); + } /* - * To get the rest of answer, - * use TCP with same server. + * All is well, or the error is fatal. Signal that the + * next nameserver ought not be tried. */ - Dprint(statp->options & RES_DEBUG, - (stdout, ";; truncated answer\n")); - *v_circuit = 1; - res_nclose(statp); - return (1); + return (resplen); } - /* - * All is well, or the error is fatal. Signal that the - * next nameserver ought not be tried. - */ - return (resplen); } #ifdef DEBUG |