etc hosts handling.

git-svn-id: file:///svn/unbound/trunk@944 be551aaa-1e26-0410-a405-d3ace91eadb9

doc/Changelog

@@ -1,6 +1,7 @@
 11 February 2008: Wouter
 	- changed library to use ub_ instead of ub_val_ as prefix.
 	- statistics output text nice.
+	- etc/hosts handling.
 
 8 February 2008: Wouter
 	- test program for multiple queries over a TCP channel.

doc/libunbound.3

@@ -19,6 +19,7 @@
 .B ub_ctx_config,
 .B ub_ctx_set_fwd,
 .B ub_ctx_resolvconf,
+.B ub_ctx_hosts,
 .B ub_ctx_add_ta,
 .B ub_ctx_add_ta_file,
 .B ub_ctx_trustedkeys,
@@ -54,6 +55,9 @@
 \fBub_ctx_resolvconf\fR(\fIstruct ub_ctx*\fR ctx, \fIchar*\fR fname);
 .LP
 \fIint\fR
+\fBub_ctx_hosts\fR(\fIstruct ub_ctx*\fR ctx, \fIchar*\fR fname);
+.LP
+\fIint\fR
 \fBub_ctx_add_ta\fR(\fIstruct ub_ctx*\fR ctx, \fIchar*\fR ta);
 .LP
 \fIint\fR
@@ -131,6 +135,12 @@ The functions are discussed in turn below.
 .TP 
 .B ub_ctx_create
 Create a new context, initialised with defaults.
+The information from /etc/resolv.conf and /etc/hosts is not utilised 
+by default. Use 
+.B ub_ctx_resolvconf
+and
+.B ub_ctx_hosts
+to read them.
 .TP
 .B ub_ctx_delete
 Delete validation context and free associated resources.
@@ -161,6 +171,13 @@ If fname NULL is passed, "/etc/resolv.conf" is used.
 At this time it is only possible to set configuration before the
 first resolve is done.
 .TP
+.B ub_ctx_hosts
+Read list of hosts from the filename given.
+Usually "/etc/hosts". When queried for, these addresses are not marked 
+DNSSEC secure. If fname NULL is passed, "/etc/hosts" is used.
+At this time it is only possible to set configuration before the
+first resolve is done.
+.TP
 .B
 ub_ctx_add_ta
 Add a trust anchor to the given context.

libunbound/libunbound.c

@@ -819,3 +819,79 @@ ub_ctx_resolvconf(struct ub_ctx* ctx, char* fname)
 	}
 	return UB_NOERROR;
 }
+
+int
+ub_ctx_hosts(struct ub_ctx* ctx, char* fname)
+{
+	FILE* in;
+	char buf[1024], ldata[1024];
+	char* parse, *addr, *name, *ins;
+	lock_basic_lock(&ctx->cfglock);
+	if(ctx->finalized) {
+		lock_basic_unlock(&ctx->cfglock);
+		errno=EINVAL;
+		return UB_AFTERFINAL;
+	}
+	lock_basic_unlock(&ctx->cfglock);
+	if(fname == NULL)
+		fname = "/etc/hosts";
+	in = fopen(fname, "r");
+	if(!in) {
+		/* error in errno! perror(fname) */
+		return UB_READFILE;
+	}
+	while(fgets(buf, (int)sizeof(buf), in)) {
+		buf[sizeof(buf)-1] = 0;
+		parse=buf;
+		while(*parse == ' ' || *parse == '\t')
+			parse++;
+		if(*parse == '#')
+			continue; /* skip comment */
+		/* format: <addr> spaces <name> spaces <name> ... */
+		addr = parse;
+		/* skip addr */
+		while(isxdigit(*parse) || *parse == '.' || *parse == ':')
+			parse++;
+		if(*parse != ' ' && *parse != '\t') {
+			/* must have whitespace after address */
+			fclose(in);
+			errno=EINVAL;
+			return UB_SYNTAX;
+		}
+		*parse++ = 0; /* end delimiter for addr ... */
+		/* go to names and add them */
+		while(*parse) {
+			while(*parse == ' ' || *parse == '\t' || *parse=='\n')
+				parse++;
+			if(*parse == 0 || *parse == '#')
+				break;
+			/* skip name, allows (too) many printable characters */
+			name = parse;
+			while('!' <= *parse && *parse <= '~')
+				parse++;
+			if(*parse)
+				*parse++ = 0; /* end delimiter for name */
+			snprintf(ldata, sizeof(ldata), "%s %s %s",
+				name, str_is_ip6(addr)?"AAAA":"A", addr);
+			ins = strdup(ldata);
+			if(!ins) {
+				/* out of memory */
+				fclose(in);
+				errno=ENOMEM;
+				return UB_NOMEM;
+			}
+			lock_basic_lock(&ctx->cfglock);
+			if(!cfg_strlist_insert(&ctx->env->cfg->local_data, 
+				ins)) {
+				lock_basic_unlock(&ctx->cfglock);
+				fclose(in);
+				free(ins);
+				errno=ENOMEM;
+				return UB_NOMEM;
+			}
+			lock_basic_unlock(&ctx->cfglock);
+		}
+	}
+	fclose(in);
+	return UB_NOERROR;
+}

libunbound/ubsyms.def

@@ -1,19 +1,20 @@
-ub_val_ctx_create
-ub_val_ctx_delete
-ub_val_ctx_config
-ub_val_ctx_set_fwd
-ub_val_ctx_resolvconf
-ub_val_ctx_add_ta
-ub_val_ctx_add_ta_file
-ub_val_ctx_trustedkeys
-ub_val_ctx_debuglevel
-ub_val_ctx_async
-ub_val_poll
-ub_val_wait
-ub_val_fd
-ub_val_process
-ub_val_resolve
-ub_val_resolve_async
-ub_val_cancel
-ub_val_resolve_free
-ub_val_strerror
+ub_ctx_create
+ub_ctx_delete
+ub_ctx_config
+ub_ctx_set_fwd
+ub_ctx_resolvconf
+ub_ctx_hosts
+ub_ctx_add_ta
+ub_ctx_add_ta_file
+ub_ctx_trustedkeys
+ub_ctx_debuglevel
+ub_ctx_async
+ub_poll
+ub_wait
+ub_fd
+ub_process
+ub_resolve
+ub_resolve_async
+ub_cancel
+ub_resolve_free
+ub_strerror

libunbound/unbound.h

@@ -193,6 +193,8 @@ typedef void (*ub_callback_t)(void*, int, struct ub_result*);
 
 /**
  * Create a resolving and validation context.
+ * The information from /etc/resolv.conf and /etc/hosts is not utilised by
+ * default. Use ub_ctx_resolvconf and ub_ctx_hosts to read them.
  * @return a new context. default initialisation.
  * 	returns NULL on error.
  */
@@ -252,6 +254,19 @@ int ub_ctx_set_fwd(struct ub_ctx* ctx, char* addr);
  */
 int ub_ctx_resolvconf(struct ub_ctx* ctx, char* fname);
 
+/**
+ * Read list of hosts from the filename given.
+ * Usually "/etc/hosts". 
+ * These addresses are not flagged as DNSSEC secure when queried for.
+ *
+ * @param ctx: context.
+ *	At this time it is only possible to set configuration before the
+ *	first resolve is done.
+ * @param fname: file name string. If NULL "/etc/hosts" is used.
+ * @return 0 if OK, else error.
+ */
+int ub_ctx_hosts(struct ub_ctx* ctx, char* fname);
+
 /**
  * Add a trust anchor to the given context.
  * The trust anchor is a string, on one line, that holds a valid DNSKEY or

testcode/asynclook.c

@@ -72,6 +72,7 @@ void usage(char* argv[])
 	printf("	-d : enable debug output\n");
 	printf("	-f addr : use addr, forward to that server\n");
 	printf("	-h : this help message\n");
+	printf("	-H fname : read hosts from fname\n");
 	printf("	-r fname : read resolv.conf from fname\n");
 	printf("	-t : use a resolver thread instead of forking a process\n");
 	printf("	-x : perform extended threaded test\n");
@@ -351,7 +352,7 @@ int main(int argc, char** argv)
 	if(argc == 1) {
 		usage(argv);
 	}
-	while( (c=getopt(argc, argv, "bcdf:hr:tx")) != -1) {
+	while( (c=getopt(argc, argv, "bcdf:hH:r:tx")) != -1) {
 		switch(c) {
 			case 'd':
 				r = ub_ctx_debuglevel(ctx, 3);
@@ -377,6 +378,16 @@ int main(int argc, char** argv)
 					return 1;
 				}
 				break;
+			case 'H':
+				r = ub_ctx_hosts(ctx, optarg);
+				if(r != 0) {
+					printf("ub_ctx_hosts "
+						"error: %s : %s\n",
+						ub_strerror(r), 
+						strerror(errno));
+					return 1;
+				}
+				break;
 			case 'f':
 				r = ub_ctx_set_fwd(ctx, optarg);
 				checkerr("ub_ctx_set_fwd", r);