- buffer overflow fix, from OpenBSD

- optimise the error number -> string mapping code

Obtained from: a diff of FreeBSD vs. OpenBSD/NetBSD rpc code.

1 files changed, 58 insertions, 110 deletions

diff --git a/lib/libc/rpc/clnt_perror.c b/lib/libc/rpc/clnt_perror.c
index 0bcd8f0..adf3bd0 100644
--- a/lib/libc/rpc/clnt_perror.c
+++ b/lib/libc/rpc/clnt_perror.c
@@ -30,7 +30,7 @@
 #if defined(LIBC_SCCS) && !defined(lint)
 /*static char *sccsid = "from: @(#)clnt_perror.c 1.15 87/10/07 Copyr 1984 Sun Micro";*/
 /*static char *sccsid = "from: @(#)clnt_perror.c	2.1 88/07/29 4.0 RPCSRC";*/
-static char *rcsid = "$Id: clnt_perror.c,v 1.4 1995/12/10 17:40:18 wpaul Exp $";
+static char *rcsid = "$Id: clnt_perror.c,v 1.5 1996/06/10 20:13:02 jraynard Exp $";
 #endif
 
 /*
@@ -48,6 +48,7 @@ static char *rcsid = "$Id: clnt_perror.c,v 1.4 1995/12/10 17:40:18 wpaul Exp $";
 #include <rpc/clnt.h>
 
 static char *auth_errmsg();
+#define CLNT_PERROR_BUFLEN 256
 
 static char *buf;
 
@@ -56,7 +57,7 @@ _buf()
 {
 
 	if (buf == 0)
-		buf = (char *)malloc(256);
+		buf = (char *)malloc(CLNT_PERROR_BUFLEN);
 	return (buf);
 }
 
@@ -69,7 +70,6 @@ clnt_sperror(rpch, s)
 	char *s;
 {
 	struct rpc_err e;
-	void clnt_perrno();
 	char *err;
 	char *str = _buf();
 	char *strstart = str;
@@ -78,10 +78,7 @@ clnt_sperror(rpch, s)
 		return (0);
 	CLNT_GETERR(rpch, &e);
 
-	(void) sprintf(str, "%s: ", s);
-	str += strlen(str);
-
-	(void) strcpy(str, clnt_sperrno(e.re_status));
+	(void) sprintf(str, "%s: %s", s, clnt_sperrno(e.re_status));
 	str += strlen(str);
 
 	switch (e.re_status) {
@@ -102,16 +99,14 @@ clnt_sperror(rpch, s)
 
 	case RPC_CANTSEND:
 	case RPC_CANTRECV:
-		(void) sprintf(str, "; errno = %s",
-		    strerror(e.re_errno));
-		str += strlen(str);
+		(void) snprintf(str, CLNT_PERROR_BUFLEN - (str - strstart),
+			"; errno = %s\n", strerror(e.re_errno));
 		break;
 
 	case RPC_VERSMISMATCH:
 		(void) sprintf(str,
-			"; low version = %lu, high version = %lu",
+			"; low version = %lu, high version = %lu\n",
 			e.re_vers.low, e.re_vers.high);
-		str += strlen(str);
 		break;
 
 	case RPC_AUTHERROR:
@@ -119,30 +114,28 @@ clnt_sperror(rpch, s)
 		(void) sprintf(str,"; why = ");
 		str += strlen(str);
 		if (err != NULL) {
-			(void) sprintf(str, "%s",err);
+			(void) sprintf(str, "%s\n",err);
 		} else {
 			(void) sprintf(str,
-				"(unknown authentication error - %d)",
+				"(unknown authentication error - %d)\n",
 				(int) e.re_why);
 		}
-		str += strlen(str);
 		break;
 
 	case RPC_PROGVERSMISMATCH:
 		(void) sprintf(str,
-			"; low version = %lu, high version = %lu",
+			"; low version = %lu, high version = %lu\n",
 			e.re_vers.low, e.re_vers.high);
-		str += strlen(str);
 		break;
 
 	default:	/* unknown */
 		(void) sprintf(str,
-			"; s1 = %lu, s2 = %lu",
+			"; s1 = %lu, s2 = %lu\n",
 			e.re_lb.s1, e.re_lb.s2);
-		str += strlen(str);
 		break;
 	}
-	(void) sprintf(str, "\n");
+	strstart[CLNT_PERROR_BUFLEN-2] = '\n';
+	strstart[CLNT_PERROR_BUFLEN-1] = '\0';
 	return(strstart) ;
 }
 
@@ -155,48 +148,25 @@ clnt_perror(rpch, s)
 }
 
 
-struct rpc_errtab {
-	enum clnt_stat status;
-	char *message;
-};
-
-static struct rpc_errtab  rpc_errlist[] = {
-	{ RPC_SUCCESS,
-		"RPC: Success" },
-	{ RPC_CANTENCODEARGS,
-		"RPC: Can't encode arguments" },
-	{ RPC_CANTDECODERES,
-		"RPC: Can't decode result" },
-	{ RPC_CANTSEND,
-		"RPC: Unable to send" },
-	{ RPC_CANTRECV,
-		"RPC: Unable to receive" },
-	{ RPC_TIMEDOUT,
-		"RPC: Timed out" },
-	{ RPC_VERSMISMATCH,
-		"RPC: Incompatible versions of RPC" },
-	{ RPC_AUTHERROR,
-		"RPC: Authentication error" },
-	{ RPC_PROGUNAVAIL,
-		"RPC: Program unavailable" },
-	{ RPC_PROGVERSMISMATCH,
-		"RPC: Program/version mismatch" },
-	{ RPC_PROCUNAVAIL,
-		"RPC: Procedure unavailable" },
-	{ RPC_CANTDECODEARGS,
-		"RPC: Server can't decode arguments" },
-	{ RPC_SYSTEMERROR,
-		"RPC: Remote system error" },
-	{ RPC_UNKNOWNHOST,
-		"RPC: Unknown host" },
-	{ RPC_UNKNOWNPROTO,
-		"RPC: Unknown protocol" },
-	{ RPC_PMAPFAILURE,
-		"RPC: Port mapper failure" },
-	{ RPC_PROGNOTREGISTERED,
-		"RPC: Program not registered"},
-	{ RPC_FAILED,
-		"RPC: Failed (unspecified error)"}
+static const char *const rpc_errlist[] = {
+	"RPC: Success",				/*  0 - RPC_SUCCESS */
+	"RPC: Can't encode arguments",		/*  1 - RPC_CANTENCODEARGS */
+	"RPC: Can't decode result",		/*  2 - RPC_CANTDECODERES */
+	"RPC: Unable to send",			/*  3 - RPC_CANTSEND */
+	"RPC: Unable to receive",		/*  4 - RPC_CANTRECV */
+	"RPC: Timed out",			/*  5 - RPC_TIMEDOUT */
+	"RPC: Incompatible versions of RPC",	/*  6 - RPC_VERSMISMATCH */
+	"RPC: Authentication error",		/*  7 - RPC_AUTHERROR */
+	"RPC: Program unavailable",		/*  8 - RPC_PROGUNAVAIL */
+	"RPC: Program/version mismatch",	/*  9 - RPC_PROGVERSMISMATCH */
+	"RPC: Procedure unavailable",		/* 10 - RPC_PROCUNAVAIL */
+	"RPC: Server can't decode arguments",	/* 11 - RPC_CANTDECODEARGS */
+	"RPC: Remote system error",		/* 12 - RPC_SYSTEMERROR */
+	"RPC: Unknown host",			/* 13 - RPC_UNKNOWNHOST */
+	"RPC: Port mapper failure",		/* 14 - RPC_PMAPFAILURE */
+	"RPC: Program not registered",		/* 15 - RPC_PROGNOTREGISTERED */
+	"RPC: Failed (unspecified error)",	/* 16 - RPC_FAILED */
+	"RPC: Unknown protocol"			/* 17 - RPC_UNKNOWNPROTO */
 };
 
 
@@ -207,13 +177,11 @@ char *
 clnt_sperrno(stat)
 	enum clnt_stat stat;
 {
-	int i;
+	unsigned int errnum = stat;
+
+	if (errnum < (sizeof(rpc_errlist)/sizeof(rpc_errlist[0])))
+		return (char *)rpc_errlist[errnum];
 
-	for (i = 0; i < sizeof(rpc_errlist)/sizeof(struct rpc_errtab); i++) {
-		if (rpc_errlist[i].status == stat) {
-			return (rpc_errlist[i].message);
-		}
-	}
 	return ("RPC: (unknown error code)");
 }
 
@@ -229,34 +197,29 @@ char *
 clnt_spcreateerror(s)
 	char *s;
 {
-	extern int sys_nerr;
 	char *str = _buf();
 
 	if (str == 0)
 		return(0);
-	(void) sprintf(str, "%s: ", s);
-	(void) strcat(str, clnt_sperrno(rpc_createerr.cf_stat));
 	switch (rpc_createerr.cf_stat) {
 	case RPC_PMAPFAILURE:
-		(void) strcat(str, " - ");
-		(void) strcat(str,
+		(void) snprintf(str, CLNT_PERROR_BUFLEN, "%s: %s - %s\n", s,
+		    clnt_sperrno(rpc_createerr.cf_stat),
 		    clnt_sperrno(rpc_createerr.cf_error.re_status));
 		break;
 
 	case RPC_SYSTEMERROR:
-		(void) strcat(str, " - ");
-		if (rpc_createerr.cf_error.re_errno > 0
-		    && rpc_createerr.cf_error.re_errno < sys_nerr)
-			(void) strcat(str,
-			    strerror(rpc_createerr.cf_error.re_errno));
-		else
-			(void) sprintf(&str[strlen(str)], "Error %d",
-			    rpc_createerr.cf_error.re_errno);
+		(void) snprintf(str, CLNT_PERROR_BUFLEN, "%s: %s - %s\n", s,
+		    clnt_sperrno(rpc_createerr.cf_stat),
+		    strerror(rpc_createerr.cf_error.re_errno));
 		break;
 	default:
+		(void) snprintf(str, CLNT_PERROR_BUFLEN, "%s: %s\n", s,
+		clnt_sperrno(rpc_createerr.cf_stat));
 		break;
 	}
-	(void) strcat(str, "\n");
+	str[CLNT_PERROR_BUFLEN-2] = '\n';
+	str[CLNT_PERROR_BUFLEN-1] = '\0';
 	return (str);
 }
 
@@ -267,40 +230,25 @@ clnt_pcreateerror(s)
 	(void) fprintf(stderr,"%s\n",clnt_spcreateerror(s));
 }
 
-struct auth_errtab {
-	enum auth_stat status;
-	char *message;
-};
-
-static struct auth_errtab auth_errlist[] = {
-	{ AUTH_OK,
-		"Authentication OK" },
-	{ AUTH_BADCRED,
-		"Invalid client credential" },
-	{ AUTH_REJECTEDCRED,
-		"Server rejected credential" },
-	{ AUTH_BADVERF,
-		"Invalid client verifier" },
-	{ AUTH_REJECTEDVERF,
-		"Server rejected verifier" },
-	{ AUTH_TOOWEAK,
-		"Client credential too weak" },
-	{ AUTH_INVALIDRESP,
-		"Invalid server verifier" },
-	{ AUTH_FAILED,
-		"Failed (unspecified error)" },
+static const char *const auth_errlist[] = {
+	"Authentication OK",			/* 0 - AUTH_OK */
+	"Invalid client credential",		/* 1 - AUTH_BADCRED */
+	"Server rejected credential",		/* 2 - AUTH_REJECTEDCRED */
+	"Invalid client verifier",		/* 3 - AUTH_BADVERF */
+	"Server rejected verifier",		/* 4 - AUTH_REJECTEDVERF */
+	"Client credential too weak",		/* 5 - AUTH_TOOWEAK */
+	"Invalid server verifier",		/* 6 - AUTH_INVALIDRESP */
+	"Failed (unspecified error)"		/* 7 - AUTH_FAILED */
 };
 
 static char *
 auth_errmsg(stat)
 	enum auth_stat stat;
 {
-	int i;
+	unsigned int errnum = stat;
+
+	if (errnum < (sizeof(auth_errlist)/sizeof(auth_errlist[0])))
+		return (char *)auth_errlist[errnum];
 
-	for (i = 0; i < sizeof(auth_errlist)/sizeof(struct auth_errtab); i++) {
-		if (auth_errlist[i].status == stat) {
-			return(auth_errlist[i].message);
-		}
-	}
 	return(NULL);
 }