[icmp-dn.git] / nss-icmp.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <nss.h>
#include <sys/types.h>
#include <fcntl.h>

enum nss_status _nss_icmp_gethostbyaddr_r(const void *addr, socklen_t len, int af, struct hostent *result, char *buffer, size_t buflen, int *errnop, int *h_errnop)
{
    int ret;
    struct retstruct {
	char *aliaslist[16];
	char *addrlist[2];
	char retaddr[16];
    } *retbuf;
    char addrbuf[1024];
    int an, thislen;
    char *p, *p2, *p3;
    u_int8_t *ap;
    pid_t child;
    int pfd[2];
    int rl;
    
    retbuf = (struct retstruct *)buffer;
    if((buflen < sizeof(*retbuf)) || (len > sizeof(retbuf->retaddr))) {
	*errnop = ENOMEM;
	*h_errnop = NETDB_INTERNAL;
	return(NSS_STATUS_UNAVAIL);
    }
    
    ap = (u_int8_t *)addr;
    if(inet_ntop(af, addr, addrbuf, sizeof(addrbuf)) == NULL) {
	*errnop = errno;
	*h_errnop = NETDB_INTERNAL;
	return(NSS_STATUS_UNAVAIL);
    }
    
    if(pipe(pfd)) {
	*errnop = errno;
	*h_errnop = NETDB_INTERNAL;
	return(NSS_STATUS_UNAVAIL);
    }
    /* I honestly don't know if it is considered OK to fork in other
     * people's programs. We need a SUID worker, though, so there's
     * little choice that I can see. */
    if((child = fork()) < 0) {
	*errnop = errno;
	*h_errnop = NETDB_INTERNAL;
	return(NSS_STATUS_UNAVAIL);
    }
    
    if(child == 0) {
	int i, fd;
	
	if((fd = open("/dev/null", O_WRONLY)) < 0)
	    exit(127);
	close(pfd[0]);
	dup2(pfd[1], 1);
	dup2(fd, 2);
	for(i = 3; i < FD_SETSIZE; i++)
	    close(i);
	
	execlp("idnlookup", "idnlookup", addrbuf, NULL);
	exit(127);
    }
    
    close(pfd[1]);
    
    rl = 0;
    do {
	ret = read(pfd[0], addrbuf + rl, sizeof(addrbuf) - rl);
	if(ret < 0) {
	    *errnop = errno;
	    *h_errnop = NETDB_INTERNAL;
	    close(pfd[0]);
	    return(NSS_STATUS_UNAVAIL);
	}
	rl += ret;
	if(rl >= sizeof(addrbuf) - 1) {
	    *errnop = ENOMEM;
	    *h_errnop = NETDB_INTERNAL;
	    close(pfd[0]);
	    return(NSS_STATUS_UNAVAIL);
	}
    } while(ret != 0);
    addrbuf[rl] = 0;
    close(pfd[0]);
    
    an = 0;
    p = addrbuf;
    p3 = buffer + sizeof(*retbuf);
    while((p2 = strchr(p, '\n')) != NULL) {
	*p2 = 0;
	thislen = p2 - p;
	if(thislen == 0)
	    continue;
	if((p3 - buffer) + thislen + 1 > buflen) {
	    *errnop = ENOMEM;
	    *h_errnop = NETDB_INTERNAL;
	    return(NSS_STATUS_UNAVAIL);
	}
	memcpy(p3, p, thislen + 1);
	retbuf->aliaslist[an] = p3;
	p3 += thislen + 1;
	p = p2 + 1;
	if(++an == 16) {
	    *errnop = ENOMEM;
	    *h_errnop = NETDB_INTERNAL;
	    return(NSS_STATUS_UNAVAIL);
	}
    }
    if(an == 0) {
	*h_errnop = TRY_AGAIN; /* XXX: Is this correct? */
	return(NSS_STATUS_NOTFOUND);
    }
    retbuf->aliaslist[an] = NULL;
    
    memcpy(retbuf->retaddr, addr, len);
    retbuf->addrlist[0] = retbuf->retaddr;
    retbuf->addrlist[1] = NULL;
    result->h_name = retbuf->aliaslist[0];
    result->h_aliases = retbuf->aliaslist;
    result->h_addr_list = retbuf->addrlist;
    result->h_addrtype = af;
    result->h_length = len;
    
    *h_errnop = NETDB_SUCCESS;
    return(NSS_STATUS_SUCCESS);
}
Commit	Line	Data
2dec74ab DC	1	#include <stdlib.h>
	2	#include <stdio.h>
	3	#include <unistd.h>
	4	#include <string.h>
	5	#include <errno.h>
	6	#include <sys/socket.h>
	7	#include <netinet/in.h>
	8	#include <netdb.h>
	9	#include <arpa/inet.h>
	10	#include <nss.h>
	11	#include <sys/types.h>
	12	#include <fcntl.h>
	13
	14	enum nss_status _nss_icmp_gethostbyaddr_r(const void addr, socklen_t len, int af, struct hostent result, char buffer, size_t buflen, int errnop, int *h_errnop)
	15	{
	16	int ret;
	17	struct retstruct {
	18	char *aliaslist[16];
	19	char *addrlist[2];
	20	char retaddr[16];
	21	} *retbuf;
	22	char addrbuf[1024];
03511d7b	23	int an, thislen;
2dec74ab DC	24	char p, p2, *p3;
	25	u_int8_t *ap;
	26	pid_t child;
	27	int pfd[2];
	28	int rl;
	29
	30	retbuf = (struct retstruct *)buffer;
	31	if((buflen < sizeof(*retbuf)) \|\| (len > sizeof(retbuf->retaddr))) {
	32	*errnop = ENOMEM;
	33	*h_errnop = NETDB_INTERNAL;
	34	return(NSS_STATUS_UNAVAIL);
	35	}
	36
	37	ap = (u_int8_t *)addr;
	38	if(inet_ntop(af, addr, addrbuf, sizeof(addrbuf)) == NULL) {
	39	*errnop = errno;
	40	*h_errnop = NETDB_INTERNAL;
	41	return(NSS_STATUS_UNAVAIL);
	42	}
	43
	44	if(pipe(pfd)) {
	45	*errnop = errno;
	46	*h_errnop = NETDB_INTERNAL;
	47	return(NSS_STATUS_UNAVAIL);
	48	}
	49	/* I honestly don't know if it is considered OK to fork in other
	50	* people's programs. We need a SUID worker, though, so there's
	51	* little choice that I can see. */
	52	if((child = fork()) < 0) {
	53	*errnop = errno;
	54	*h_errnop = NETDB_INTERNAL;
	55	return(NSS_STATUS_UNAVAIL);
	56	}
	57
	58	if(child == 0) {
	59	int i, fd;
	60
	61	if((fd = open("/dev/null", O_WRONLY)) < 0)
	62	exit(127);
	63	close(pfd[0]);
	64	dup2(pfd[1], 1);
	65	dup2(fd, 2);
	66	for(i = 3; i < FD_SETSIZE; i++)
	67	close(i);
	68
	69	execlp("idnlookup", "idnlookup", addrbuf, NULL);
	70	exit(127);
	71	}
	72
	73	close(pfd[1]);
	74
	75	rl = 0;
	76	do {
	77	ret = read(pfd[0], addrbuf + rl, sizeof(addrbuf) - rl);
	78	if(ret < 0) {
	79	*errnop = errno;
	80	*h_errnop = NETDB_INTERNAL;
	81	close(pfd[0]);
	82	return(NSS_STATUS_UNAVAIL);
	83	}
	84	rl += ret;
	85	if(rl >= sizeof(addrbuf) - 1) {
	86	*errnop = ENOMEM;
	87	*h_errnop = NETDB_INTERNAL;
88	close(pfd[0]);
89	return(NSS_STATUS_UNAVAIL);
90	}
91	} while(ret != 0);
92	addrbuf[rl] = 0;
93	close(pfd[0]);
94
95	an = 0;
96	p = addrbuf;
97	p3 = buffer + sizeof(*retbuf);
98	while((p2 = strchr(p, '\n')) != NULL) {
99	*p2 = 0;
03511d7b DC	100	thislen = p2 - p;
	101	if(thislen == 0)
	102	continue;
	103	if((p3 - buffer) + thislen + 1 > buflen) {
2dec74ab DC	104	*errnop = ENOMEM;
	105	*h_errnop = NETDB_INTERNAL;
	106	return(NSS_STATUS_UNAVAIL);
	107	}
03511d7b	108	memcpy(p3, p, thislen + 1);
2dec74ab	109	retbuf->aliaslist[an] = p3;
03511d7b	110	p3 += thislen + 1;
2dec74ab DC	111	p = p2 + 1;
	112	if(++an == 16) {
	113	*errnop = ENOMEM;
	114	*h_errnop = NETDB_INTERNAL;
	115	return(NSS_STATUS_UNAVAIL);
	116	}
	117	}
	118	if(an == 0) {
03511d7b	119	h_errnop = TRY_AGAIN; / XXX: Is this correct? */
2dec74ab DC	120	return(NSS_STATUS_NOTFOUND);
	121	}
	122	retbuf->aliaslist[an] = NULL;
	123
	124	memcpy(retbuf->retaddr, addr, len);
	125	retbuf->addrlist[0] = retbuf->retaddr;
	126	retbuf->addrlist[1] = NULL;
	127	result->h_name = retbuf->aliaslist[0];
	128	result->h_aliases = retbuf->aliaslist;
	129	result->h_addr_list = retbuf->addrlist;
	130	result->h_addrtype = af;
	131	result->h_length = len;
	132
	133	*h_errnop = NETDB_SUCCESS;
	134	return(NSS_STATUS_SUCCESS);
	135	}