Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 830 insertions, 0 deletions

diff --git a/source3/registry/reg_format.c b/source3/registry/reg_format.c
new file mode 100644
index 0000000..f353f79
--- /dev/null
+++ b/source3/registry/reg_format.c
@@ -0,0 +1,830 @@
+/*
+ * Samba Unix/Linux SMB client library
+ *
+ * Copyright (C) Gregor Beck 2010
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @brief  Format dot.reg files
+ * @file   reg_format.c
+ * @author Gregor Beck <gb@sernet.de>
+ * @date   Sep 2010
+ */
+
+#include "includes.h"
+#include "reg_format.h"
+#include "reg_parse.h"
+#include "reg_parse_internal.h"
+#include "cbuf.h"
+#include "srprs.h"
+#include "registry.h"
+#include "registry/reg_objects.h"
+#include <assert.h>
+
+static void cstr_unescape(char* val)
+{
+	all_string_sub(val, "\\r", "\r", 0);
+	all_string_sub(val, "\\n", "\n", 0);
+	all_string_sub(val, "\\t", "\t", 0);
+	all_string_sub(val, "\\\\", "\\", 0);
+}
+
+/******************************************************************************/
+
+/**
+ * Print value assign to stream.
+ *
+ * @param[out] ost outstream
+ * @param[in]  name string
+ *
+ * @return number of bytes written, -1 on error
+ * @see srprs_val_name
+ */
+static int cbuf_print_value_assign(cbuf* ost, const char* name) {
+	size_t ret = 0;
+	int n;
+	if (*name == '\0') {
+		n = cbuf_putc(ost, '@');
+	} else {
+		n = cbuf_print_quoted_string(ost, name);
+	}
+	if (n < 0) {
+		return n;
+	}
+	ret += n;
+
+	n = cbuf_putc(ost, '=');
+	if (n < 0) {
+		return n;
+	}
+	ret += n;
+
+	return ret;
+}
+
+enum fmt_hive {
+	FMT_HIVE_PRESERVE=0,
+	FMT_HIVE_SHORT,
+	FMT_HIVE_LONG
+};
+
+
+struct fmt_key {
+	enum fmt_hive hive_fmt;
+	enum fmt_case hive_case;
+	enum fmt_case key_case;
+	const char*   sep;
+};
+
+
+static int
+cbuf_print_hive(cbuf* ost, const char* hive, int len, const struct fmt_key* fmt)
+{
+	if (fmt->hive_fmt != FMT_HIVE_PRESERVE) {
+		const struct hive_info* hinfo = hive_info(hive);
+		if (hinfo == NULL) {
+			DEBUG(0, ("Unknown hive %*s\n", len, hive));
+		} else {
+			switch(fmt->hive_fmt) {
+			case FMT_HIVE_SHORT:
+				hive = hinfo->short_name;
+				len  = hinfo->short_name_len;
+				break;
+			case FMT_HIVE_LONG:
+				hive = hinfo->long_name;
+				len  = hinfo->long_name_len;
+				break;
+			default:
+				DEBUG(0, ("Unsupported hive format %d\n",
+					  (int)fmt->hive_fmt));
+				return -1;
+			}
+		}
+	}
+
+	return cbuf_puts_case(ost, hive, len, fmt->hive_case);
+}
+
+static int
+cbuf_print_keyname(cbuf* ost, const char* key[], int n, const struct fmt_key* fmt)
+{
+	int r;
+	size_t ret = 0;
+	size_t pos = cbuf_getpos(ost);
+	bool hive = true;
+
+	for (; n>0; key++, n--) {
+		const char* start = *key;
+		while(*start != '\0') {
+			const char* end = start;
+			while(*end != '\\' && *end != '\0') {
+				end++;
+			}
+
+			if (hive) {
+				r = cbuf_print_hive(ost, start, end-start, fmt);
+				if (r < 0) {
+					goto fail;
+				}
+
+				ret += r;
+				hive = false;
+			} else {
+				r = cbuf_puts(ost, fmt->sep, -1);
+				if (r < 0) {
+					goto fail;
+				}
+				ret += r;
+
+				r = cbuf_puts_case(ost, start, end-start, fmt->key_case);
+				if (r < 0) {
+					goto fail;
+				}
+				ret += r;
+			}
+
+			while(*end == '\\') {
+				end++;
+			}
+			start = end;
+		}
+	}
+	return ret;
+fail:
+	cbuf_setpos(ost, pos);
+	return r;
+}
+/**@}*/
+
+/**
+ * @defgroup reg_format Format dot.reg file.
+ * @{
+ */
+
+struct reg_format
+{
+	struct reg_parse_callback reg_parse_callback;
+	struct reg_format_callback call;
+	unsigned flags;
+	smb_iconv_t fromUTF16;
+	const char* sep;
+};
+
+int reg_format_value_delete(struct reg_format* f, const char* name)
+{
+	int ret;
+	cbuf* line = cbuf_new(f);
+
+	ret = cbuf_print_value_assign(line, name);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = cbuf_putc(line, '-');
+	if (ret < 0 ) {
+		goto done;
+	}
+
+	ret = f->call.writeline(f->call.data, cbuf_gets(line, 0));
+done:
+	talloc_free(line);
+	return ret;
+}
+
+/* Todo: write hex if str contains CR or LF */
+static int
+reg_format_value_sz(struct reg_format* f, const char* name, const char* str)
+{
+	int ret;
+	cbuf* line = cbuf_new(f);
+
+	ret = cbuf_print_value_assign(line, name);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = cbuf_print_quoted_string(line, str);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = f->call.writeline(f->call.data, cbuf_gets(line, 0));
+
+done:
+	talloc_free(line);
+	return ret;
+}
+
+static int reg_format_value_dw(struct reg_format* f, const char* name, uint32_t dw)
+{
+	int ret;
+	cbuf* line = cbuf_new(f);
+
+	ret = cbuf_print_value_assign(line, name);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = cbuf_printf(line, "dword:%08x", dw);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = f->call.writeline(f->call.data, cbuf_gets(line, 0));
+done:
+	talloc_free(line);
+	return ret;
+}
+
+static int reg_format_value_hex(struct reg_format* f, const char* name, uint32_t type,
+				const void* data, size_t len)
+{
+	int n;
+	int cpl=0;
+	int ret=0;
+	const unsigned char* ptr;
+
+	cbuf* line = cbuf_new(f);
+
+	n = cbuf_print_value_assign(line, name);
+	if (n < 0) {
+		ret = n;
+		goto done;
+	}
+
+	cpl += n;
+
+	if (type==REG_BINARY && !(f->flags & REG_FMT_HEX_BIN)) {
+		n=cbuf_puts(line, "hex:", -1);
+	} else {
+		n=cbuf_printf(line, "hex(%x):", type);
+	}
+	if (n < 0) {
+		ret = n;
+		goto done;
+	}
+
+	cpl += n;
+
+	for (ptr=(const unsigned char *)data; len>1; len--,ptr++) {
+		n = cbuf_printf(line, "%02x,", (unsigned)(*ptr));
+		if (n < 0) {
+			return n;
+		}
+		cpl += n;
+
+		if ( cpl > 76 ) {
+			n = cbuf_putc(line, '\\');
+			if (n< 0) {
+				return n;
+			}
+
+			n = f->call.writeline(f->call.data, cbuf_gets(line,0));
+			if (n < 0) {
+				ret = n;
+				goto done;
+			}
+			ret += n;
+
+			cbuf_clear(line);
+			cpl = cbuf_puts(line, "  ", -1);
+			if (cpl < 0) {
+				ret = cpl;
+				goto done;
+			}
+		}
+	}
+
+	if ( len > 0 ) {
+		n = cbuf_printf(line, "%02x", (unsigned)(*ptr));
+		if (n < 0) {
+			ret = n;
+			goto done;
+		}
+		cpl += n;
+	}
+
+	n = f->call.writeline(f->call.data, cbuf_gets(line,0));
+	if (n < 0) {
+		ret = n;
+		goto done;
+	}
+	ret += n;
+done:
+	talloc_free(line);
+	return ret;
+}
+
+static bool is_zero_terminated_ucs2(const uint8_t* data, size_t len) {
+	const size_t idx = len/sizeof(smb_ucs2_t);
+	const smb_ucs2_t *str = (const smb_ucs2_t*)data;
+
+	if ((len % sizeof(smb_ucs2_t)) != 0) {
+		return false;
+	}
+
+	if (idx == 0) {
+		return false;
+	}
+
+	return (str[idx-1] == 0);
+}
+
+int reg_format_value(struct reg_format* f, const char* name, uint32_t type,
+		     const uint8_t* data, size_t len)
+{
+	int ret = 0;
+	void* mem_ctx = talloc_new(f);
+
+	switch (type) {
+	case REG_SZ:
+		if (!(f->flags & REG_FMT_HEX_SZ)
+		    && is_zero_terminated_ucs2(data, len))
+		{
+			char* str = NULL;
+			size_t dlen;
+			if (pull_ucs2_talloc(mem_ctx, &str, (const smb_ucs2_t*)data, &dlen)) {
+				ret = reg_format_value_sz(f, name, str);
+				goto done;
+			} else {
+				DEBUG(0, ("reg_format_value %s: "
+					  "pull_ucs2_talloc failed"
+					  ", try to write hex\n", name));
+			}
+		}
+		break;
+
+	case REG_DWORD:
+		if (!(f->flags & REG_FMT_HEX_SZ) && (len == sizeof(uint32_t))) {
+			uint32_t dw = IVAL(data,0);
+			ret = reg_format_value_dw(f, name, dw);
+			goto done;
+		}
+		break;
+
+	case REG_MULTI_SZ:
+	case REG_EXPAND_SZ:
+		if (f->fromUTF16 && (f->fromUTF16 != ((smb_iconv_t)-1))) {
+			char* str = NULL;
+			size_t dlen = iconvert_talloc(mem_ctx, f->fromUTF16,
+						      (const char*)data, len, &str);
+			if (dlen != -1) {
+				ret = reg_format_value_hex(f, name, type, str, dlen);
+				goto done;
+			} else {
+				DEBUG(0, ("reg_format_value %s: "
+					  "iconvert_talloc failed"
+					  ", try to write hex\n", name));
+			}
+		}
+		break;
+	default:
+		break;
+	}
+
+	ret = reg_format_value_hex(f, name, type, data, len);
+done:
+	talloc_free(mem_ctx);
+	return ret;
+}
+
+
+int reg_format_comment(struct reg_format* f, const char* txt)
+{
+	int ret;
+	cbuf* line = cbuf_new(f);
+
+	ret = cbuf_putc(line,';');
+	if (ret<0) {
+		goto done;
+	}
+
+	ret = cbuf_puts(line, txt, -1);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = f->call.writeline(f->call.data, cbuf_gets(line, 0));
+done:
+	talloc_free(line);
+	return ret;
+}
+
+
+/******************************************************************************/
+
+
+
+struct reg_format* reg_format_new(const void* talloc_ctx,
+				  struct reg_format_callback cb,
+				  const char* str_enc, unsigned flags,
+				  const char* sep)
+{
+	static const struct reg_parse_callback reg_parse_callback_default = {
+		.key = (reg_parse_callback_key_t)&reg_format_key,
+		.val = (reg_parse_callback_val_t)&reg_format_value,
+		.val_del = (reg_parse_callback_val_del_t)&reg_format_value_delete,
+		.comment = (reg_parse_callback_comment_t)&reg_format_comment,
+	};
+
+	struct reg_format* f = talloc_zero(talloc_ctx, struct reg_format);
+	if (f == NULL) {
+		return NULL;
+	}
+
+	f->reg_parse_callback = reg_parse_callback_default;
+	f->reg_parse_callback.data = f;
+
+	f->call = cb;
+	f->flags = flags;
+	f->sep   = sep;
+
+	if (str_enc && !set_iconv(&f->fromUTF16, str_enc, "UTF-16LE")) {
+		DEBUG(0, ("reg_format_new: failed to set encoding: %s\n",
+			  str_enc));
+		goto fail;
+	}
+
+	assert(&f->reg_parse_callback == (struct reg_parse_callback*)f);
+	return f;
+fail:
+	talloc_free(f);
+	return NULL;
+}
+
+int reg_format_set_options(struct reg_format* fmt, const char* options)
+{
+	static const char* DEFAULT ="enc=unix,flags=0,sep=\\";
+
+	int ret = 0;
+	char *key, *val;
+	void* ctx = talloc_new(fmt);
+
+	if (options == NULL) {
+		options = DEFAULT;
+	}
+
+	while (srprs_option(&options, ctx, &key, &val)) {
+		if ((strcmp(key, "enc") == 0) || (strcmp(key, "strenc") == 0)) {
+			if (!set_iconv(&fmt->fromUTF16, val, "UTF-16LE")) {
+				DEBUG(0, ("Failed to set encoding: %s\n", val));
+				ret = -1;
+			}
+		} else if ((strcmp(key, "flags") == 0) && (val != NULL)) {
+			char* end = NULL;
+			if (val != NULL) {
+				fmt->flags = strtol(val, &end, 0);
+			}
+			if ((end==NULL) || (*end != '\0')) {
+				DEBUG(0, ("Invalid flags format: %s\n",
+					  val ? val : "<NULL>"));
+				ret = -1;
+			}
+		} else if ((strcmp(key, "sep") == 0) && (val != NULL)) {
+			cstr_unescape(val);
+			fmt->sep = talloc_steal(fmt, val);
+		}
+
+		/* else if (strcmp(key, "hive") == 0) { */
+		/* 	if (strcmp(val, "short") == 0) { */
+		/* 		f->hive_fmt = REG_FMT_SHORT_HIVES; */
+		/* 	} else if (strcmp(val, "long") == 0) { */
+		/* 		f->hive_fmt = REG_FMT_LONG_HIVES; */
+		/* 	} else if (strcmp(val, "preserve") == 0) { */
+		/* 		f->hive_fmt = REG_FMT_PRESERVE_HIVES; */
+		/* 	} else { */
+		/* 		DEBUG(0, ("Invalid hive format: %s\n", val)); */
+		/* 		ret = -1; */
+		/* 	} */
+		/* } */
+	}
+	talloc_free(ctx);
+	return ret;
+}
+
+int reg_format_key(struct reg_format* f, const char* key[], size_t n, bool del)
+{
+	int ret, r;
+	cbuf* line = cbuf_new(f);
+	struct fmt_key key_fmt = {
+		.key_case  = (f->flags >>  4) & 0x0F,
+		.hive_case = (f->flags >>  8) & 0x0F,
+		.hive_fmt  = (f->flags >> 12) & 0x0F,
+		.sep       = f->sep,
+	};
+
+	ret = cbuf_putc(line, '[');
+	if (ret < 0) {
+		goto done;
+	}
+
+	if (del) {
+		ret = cbuf_putc(line, '-');
+		if (ret < 0) {
+			goto done;
+		}
+	}
+
+	ret = cbuf_print_keyname(line, key, n, &key_fmt);
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = cbuf_putc(line, ']');
+	if (ret < 0) {
+		goto done;
+	}
+
+	ret = f->call.writeline(f->call.data, "");
+	if (ret < 0) {
+		goto done;
+	}
+
+	r = f->call.writeline(f->call.data, cbuf_gets(line, 0));
+	if (r < 0) {
+		ret = r;
+		goto done;
+	}
+	ret += r;
+
+done:
+	talloc_free(line);
+	return ret;
+}
+
+
+int reg_format_registry_key(struct reg_format* f, struct registry_key* key,
+			    bool del)
+{
+	const char *knames[1];
+	knames[0] = key->key->name;
+	return reg_format_key(f, knames, 1, del);
+}
+
+int reg_format_registry_value(struct reg_format* f, const char* name,
+			      struct registry_value* val)
+{
+	return reg_format_value(f, name, val->type,
+				val->data.data, val->data.length);
+}
+
+int reg_format_regval_blob(struct reg_format* f, const char* name,
+			   struct regval_blob* val)
+{
+
+	return reg_format_value(f,
+				name ? name : regval_name(val),
+				regval_type(val),
+				regval_data_p(val),
+				regval_size(val));
+}
+
+/**@}*/
+
+
+struct reg_format_file
+{
+	FILE* file;
+	const char* encoding;
+	smb_iconv_t fromUnix;
+	char* nl;
+	size_t nl_len;
+};
+
+
+static int reg_format_file_close(struct reg_format* fmt)
+{
+	struct reg_format_file* fmt_ctx
+		= (struct reg_format_file*) fmt->call.data;
+	int ret = 0;
+	FILE* file = fmt_ctx->file;
+
+	if (fmt_ctx->encoding) {
+		char buf[32];
+		snprintf(buf, sizeof(buf), "coding: %s", fmt_ctx->encoding);
+		reg_format_comment(fmt, "Local Variables:");
+		reg_format_comment(fmt, buf);
+		reg_format_comment(fmt, "End:");
+	}
+
+	if (file != NULL) {
+		ret = fclose(file);
+	}
+
+	return ret;
+}
+
+static int reg_format_file_writeline(void* ptr, const char* line)
+{
+	size_t size;
+	char* dst=NULL;
+	struct reg_format_file* fmt_ctx = (struct reg_format_file*)ptr;
+	int ret, r;
+
+	size = iconvert_talloc(ptr, fmt_ctx->fromUnix, line, strlen(line), &dst);
+	if (size == -1 ) {
+		DEBUG(0, ("reg_format_file_writeline: iconvert_talloc failed >%s<\n",  line));
+		return -1;
+	}
+
+	ret = fwrite(dst, 1, size, fmt_ctx->file);
+	if (ret < 0) {
+		goto done;
+	}
+
+	r = fwrite(fmt_ctx->nl, 1, fmt_ctx->nl_len, fmt_ctx->file);
+	ret = (r < 0) ? r : ret + r;
+
+done:
+	talloc_free(dst);
+	return ret;
+}
+
+struct reg_format_file_opt {
+	const char* head;
+	const char* nl;
+	const char* enc;
+	bool bom;
+	const char* str_enc;
+	unsigned flags;
+	const char* sep;
+};
+
+static struct reg_format_file_opt reg_format_file_opt(void* mem_ctx, const char* opt)
+{
+	static const struct reg_format_file_opt REG4 = {
+		.head = "REGEDIT4",
+		.nl   = "\r\n",
+		.enc  = "dos",
+		.str_enc = "dos",
+		.bom  = false,
+		.flags = (FMT_HIVE_LONG << 12),
+		.sep   = "\\",
+	};
+
+	static const struct reg_format_file_opt REG5 = {
+		.head = "Windows Registry Editor Version 5.00",
+		.nl   = "\r\n",
+		.enc  = "UTF-16LE",
+		.str_enc = "UTF-16LE",
+		.bom  = true,
+		.flags = (FMT_HIVE_LONG << 12),
+		.sep   = "\\",
+	};
+
+	struct reg_format_file_opt ret = {
+		.head = REG5.head,
+		.nl   = "\n",
+		.enc  = "unix",
+		.bom  = false,
+		.str_enc = "UTF-16LE",
+		.flags = 0,
+		.sep   = "\\",
+	};
+
+	void* tmp_ctx = talloc_new(mem_ctx);
+
+	char *key, *val;
+
+	if (opt == NULL) {
+		goto done;
+	}
+
+	while(srprs_option(&opt, tmp_ctx, &key, &val)) {
+		if (strcmp(key, "enc") == 0) {
+			ret.enc     = talloc_steal(mem_ctx, val);
+			ret.str_enc = ret.enc;
+		} else if (strcmp(key, "strenc") == 0) {
+			ret.str_enc = talloc_steal(mem_ctx, val);
+		} else if (strcmp(key, "fileenc") == 0) {
+			ret.enc = talloc_steal(mem_ctx, val);
+		} else if ((strcmp(key, "flags") == 0) && (val != NULL)) {
+			char* end = NULL;
+			if (val != NULL) {
+				ret.flags = strtol(val, &end, 0);
+			}
+			if ((end==NULL) || (*end != '\0')) {
+				DEBUG(0, ("Invalid flags format: %s\n",
+					  val ? val : "<NULL>"));
+			}
+		} else if ((strcmp(key, "sep") == 0) && (val != NULL)) {
+			cstr_unescape(val);
+			ret.sep = talloc_steal(mem_ctx, val);
+		} else if (strcmp(key, "head") == 0) {
+			cstr_unescape(val);
+			ret.head = talloc_steal(mem_ctx, val);
+		} else if (strcmp(key, "nl") == 0) {
+			cstr_unescape(val);
+			ret.nl = talloc_steal(mem_ctx, val);
+		} else if (strcmp(key, "bom") == 0) {
+			if (val == NULL) {
+				ret.bom = true;
+			} else {
+				ret.bom = atoi(val);
+			}
+		} else if (strcmp(key, "regedit4") == 0) {
+			ret = REG4;
+		} else if (strcmp(key, "regedit5") == 0) {
+			ret = REG5;
+		}
+	}
+done:
+	talloc_free(tmp_ctx);
+	return ret;
+}
+
+
+struct reg_format* reg_format_file(const void* talloc_ctx,
+				   const char* filename,
+				   const char* options)
+{
+	struct reg_format_file* fmt_ctx;
+	struct reg_format* fmt;
+	int ret;
+	struct reg_format_file_opt opt;
+
+	struct reg_format_callback reg_format_cb = {
+		.writeline = &reg_format_file_writeline
+	};
+
+	fmt_ctx = talloc_zero(talloc_ctx, struct reg_format_file);
+	if (fmt_ctx == NULL) {
+		errno = ENOMEM;
+		return NULL;
+	}
+
+	opt = reg_format_file_opt(fmt_ctx, options);
+
+	reg_format_cb.data = fmt_ctx;
+
+	fmt = reg_format_new(talloc_ctx, reg_format_cb,
+			     opt.str_enc, opt.flags, opt.sep);
+	if (fmt == NULL) {
+		errno = ENOMEM;
+		talloc_free(fmt_ctx);
+		return NULL;
+	}
+
+	talloc_steal(fmt, fmt_ctx);
+
+	if (!set_iconv(&fmt->fromUTF16, opt.str_enc, "UTF-16LE")) { /* HACK */
+		DEBUG(0, ("reg_format_file: failed to set string encoding %s\n",
+			      opt.str_enc));
+		goto fail;
+	}
+
+	if (!set_iconv(&fmt_ctx->fromUnix, opt.enc, "unix")) {
+		DEBUG(0, ("reg_format_file: failed to set file encoding %s\n",
+			  opt.enc));
+		goto fail;
+	}
+	fmt_ctx->encoding = talloc_strdup(fmt_ctx, smbreg_get_charset(opt.enc));
+
+	fmt_ctx->file = fopen(filename, "w");
+	if (fmt_ctx->file == NULL) {
+		DEBUG(0, ("reg_format_file: fopen failed: %s\n", strerror(errno)));
+		goto fail;
+	}
+
+	if (setvbuf(fmt_ctx->file, NULL, _IOFBF, 64000) < 0) {
+		DEBUG(0, ("reg_format_file: setvbuf failed: %s\n", strerror(errno)));
+	}
+
+	talloc_set_destructor(fmt, reg_format_file_close);
+
+	fmt_ctx->nl_len = iconvert_talloc(fmt, fmt_ctx->fromUnix, opt.nl, strlen(opt.nl), &fmt_ctx->nl);
+	if (fmt_ctx->nl_len == -1) {
+		DEBUG(0, ("iconvert_talloc failed\n"));
+		goto fail;
+	}
+
+	if (opt.bom) {
+		ret = write_bom(fmt_ctx->file, opt.enc, -1);
+		if (ret < 0) {
+			goto fail;
+		}
+	}
+
+	ret = fmt->call.writeline(fmt->call.data, opt.head);
+	if (ret < 0) {
+		goto fail;
+	}
+
+	return fmt;
+fail:
+	talloc_free(fmt);
+	return NULL;
+}