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1 // Copyright 2018 The Chromium OS Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 //! This module writes Flattened Devicetree blobs as defined here:
6 //! <https://devicetree-specification.readthedocs.io/en/stable/flattened-format.html>
7 
8 use std::collections::BTreeMap;
9 use std::convert::TryInto;
10 use std::ffi::CString;
11 use std::io;
12 use std::mem::size_of;
13 
14 use remain::sorted;
15 use thiserror::Error as ThisError;
16 
17 #[sorted]
18 #[derive(ThisError, Debug)]
19 pub enum Error {
20     #[error("Parse error reading FDT parameters")]
21     FdtFileParseError,
22     #[error("Error writing FDT to guest memory")]
23     FdtGuestMemoryWriteError,
24     #[error("I/O error reading FDT parameters code={0}")]
25     FdtIoError(io::Error),
26     #[error("Strings cannot contain NUL")]
27     InvalidString,
28     #[error("Attempted to end a node that was not the most recent")]
29     OutOfOrderEndNode,
30     #[error("Properties may not be added after a node has been ended")]
31     PropertyAfterEndNode,
32     #[error("Property value size must fit in 32 bits")]
33     PropertyValueTooLarge,
34     #[error("Total size must fit in 32 bits")]
35     TotalSizeTooLarge,
36     #[error("Attempted to call finish without ending all nodes")]
37     UnclosedNode,
38 }
39 
40 pub type Result<T> = std::result::Result<T, Error>;
41 
42 const FDT_HEADER_SIZE: usize = 40;
43 const FDT_VERSION: u32 = 17;
44 const FDT_LAST_COMP_VERSION: u32 = 16;
45 
46 const FDT_MAGIC: u32 = 0xd00dfeed;
47 
48 const FDT_BEGIN_NODE: u32 = 0x00000001;
49 const FDT_END_NODE: u32 = 0x00000002;
50 const FDT_PROP: u32 = 0x00000003;
51 const FDT_END: u32 = 0x00000009;
52 
53 /// Interface for writing a Flattened Devicetree (FDT) and emitting a Devicetree Blob (DTB).
54 ///
55 /// # Example
56 ///
57 /// ```rust
58 /// use arch::fdt::FdtWriter;
59 ///
60 /// # fn main() -> arch::fdt::Result<()> {
61 /// let mut fdt = FdtWriter::new(&[]);
62 /// let root_node = fdt.begin_node("")?;
63 /// fdt.property_string("compatible", "linux,dummy-virt")?;
64 /// fdt.property_u32("#address-cells", 0x2)?;
65 /// fdt.property_u32("#size-cells", 0x2)?;
66 /// let chosen_node = fdt.begin_node("chosen")?;
67 /// fdt.property_u32("linux,pci-probe-only", 1)?;
68 /// fdt.property_string("bootargs", "panic=-1 console=hvc0 root=/dev/vda")?;
69 /// fdt.end_node(chosen_node)?;
70 /// fdt.end_node(root_node)?;
71 /// let dtb = fdt.finish(0x1000)?;
72 /// # Ok(())
73 /// # }
74 /// ```
75 pub struct FdtWriter {
76     data: Vec<u8>,
77     off_mem_rsvmap: u32,
78     off_dt_struct: u32,
79     strings: Vec<u8>,
80     string_offsets: BTreeMap<CString, u32>,
81     node_depth: usize,
82     node_ended: bool,
83     boot_cpuid_phys: u32,
84 }
85 
86 /// Reserved physical memory region.
87 ///
88 /// This represents an area of physical memory reserved by the firmware and unusable by the OS.
89 /// For example, this could be used to preserve bootloader code or data used at runtime.
90 pub struct FdtReserveEntry {
91     /// Physical address of the beginning of the reserved region.
92     pub address: u64,
93     /// Size of the reserved region in bytes.
94     pub size: u64,
95 }
96 
97 /// Handle to an open node created by `FdtWriter::begin_node`.
98 ///
99 /// This must be passed back to `FdtWriter::end_node` to close the nodes.
100 /// Nodes must be closed in reverse order as they were opened, matching the nesting structure
101 /// of the devicetree.
102 #[derive(Debug)]
103 pub struct FdtWriterNode {
104     depth: usize,
105 }
106 
107 impl FdtWriter {
108     /// Create a new Flattened Devicetree writer instance.
109     ///
110     /// # Arguments
111     ///
112     /// `mem_reservations` - reserved physical memory regions to list in the FDT header.
new(mem_reservations: &[FdtReserveEntry]) -> Self113     pub fn new(mem_reservations: &[FdtReserveEntry]) -> Self {
114         let data = vec![0u8; FDT_HEADER_SIZE]; // Reserve space for header.
115 
116         let mut fdt = FdtWriter {
117             data,
118             off_mem_rsvmap: 0,
119             off_dt_struct: 0,
120             strings: Vec::new(),
121             string_offsets: BTreeMap::new(),
122             node_depth: 0,
123             node_ended: false,
124             boot_cpuid_phys: 0,
125         };
126 
127         fdt.align(8);
128         fdt.off_mem_rsvmap = fdt.data.len() as u32;
129         fdt.write_mem_rsvmap(mem_reservations);
130 
131         fdt.align(4);
132         fdt.off_dt_struct = fdt.data.len() as u32;
133 
134         fdt
135     }
136 
write_mem_rsvmap(&mut self, mem_reservations: &[FdtReserveEntry])137     fn write_mem_rsvmap(&mut self, mem_reservations: &[FdtReserveEntry]) {
138         for rsv in mem_reservations {
139             self.append_u64(rsv.address);
140             self.append_u64(rsv.size);
141         }
142 
143         self.append_u64(0);
144         self.append_u64(0);
145     }
146 
147     /// Set the `boot_cpuid_phys` field of the devicetree header.
set_boot_cpuid_phys(&mut self, boot_cpuid_phys: u32)148     pub fn set_boot_cpuid_phys(&mut self, boot_cpuid_phys: u32) {
149         self.boot_cpuid_phys = boot_cpuid_phys;
150     }
151 
152     // Append `num_bytes` padding bytes (0x00).
pad(&mut self, num_bytes: usize)153     fn pad(&mut self, num_bytes: usize) {
154         self.data.extend(std::iter::repeat(0).take(num_bytes));
155     }
156 
157     // Append padding bytes (0x00) until the length of data is a multiple of `alignment`.
align(&mut self, alignment: usize)158     fn align(&mut self, alignment: usize) {
159         let offset = self.data.len() % alignment;
160         if offset != 0 {
161             self.pad(alignment - offset);
162         }
163     }
164 
165     // Rewrite the value of a big-endian u32 within data.
update_u32(&mut self, offset: usize, val: u32)166     fn update_u32(&mut self, offset: usize, val: u32) {
167         let data_slice = &mut self.data[offset..offset + 4];
168         data_slice.copy_from_slice(&val.to_be_bytes());
169     }
170 
append_u32(&mut self, val: u32)171     fn append_u32(&mut self, val: u32) {
172         self.data.extend_from_slice(&val.to_be_bytes());
173     }
174 
append_u64(&mut self, val: u64)175     fn append_u64(&mut self, val: u64) {
176         self.data.extend_from_slice(&val.to_be_bytes());
177     }
178 
179     /// Open a new FDT node.
180     ///
181     /// The node must be closed using `end_node`.
182     ///
183     /// # Arguments
184     ///
185     /// `name` - name of the node; must not contain any NUL bytes.
begin_node(&mut self, name: &str) -> Result<FdtWriterNode>186     pub fn begin_node(&mut self, name: &str) -> Result<FdtWriterNode> {
187         let name_cstr = CString::new(name).map_err(|_| Error::InvalidString)?;
188         self.append_u32(FDT_BEGIN_NODE);
189         self.data.extend(name_cstr.to_bytes_with_nul());
190         self.align(4);
191         self.node_depth += 1;
192         self.node_ended = false;
193         Ok(FdtWriterNode {
194             depth: self.node_depth,
195         })
196     }
197 
198     /// Close a node previously opened with `begin_node`.
end_node(&mut self, node: FdtWriterNode) -> Result<()>199     pub fn end_node(&mut self, node: FdtWriterNode) -> Result<()> {
200         if node.depth != self.node_depth {
201             return Err(Error::OutOfOrderEndNode);
202         }
203 
204         self.append_u32(FDT_END_NODE);
205         self.node_depth -= 1;
206         self.node_ended = true;
207         Ok(())
208     }
209 
210     // Find an existing instance of a string `s`, or add it to the strings block.
211     // Returns the offset into the strings block.
intern_string(&mut self, s: CString) -> u32212     fn intern_string(&mut self, s: CString) -> u32 {
213         if let Some(off) = self.string_offsets.get(&s) {
214             *off
215         } else {
216             let off = self.strings.len() as u32;
217             self.strings.extend_from_slice(s.to_bytes_with_nul());
218             self.string_offsets.insert(s, off);
219             off
220         }
221     }
222 
223     /// Write a property.
224     ///
225     /// # Arguments
226     ///
227     /// `name` - name of the property; must not contain any NUL bytes.
228     /// `val` - value of the property (raw byte array).
property(&mut self, name: &str, val: &[u8]) -> Result<()>229     pub fn property(&mut self, name: &str, val: &[u8]) -> Result<()> {
230         if self.node_ended {
231             return Err(Error::PropertyAfterEndNode);
232         }
233 
234         let name_cstr = CString::new(name).map_err(|_| Error::InvalidString)?;
235 
236         let len = val
237             .len()
238             .try_into()
239             .map_err(|_| Error::PropertyValueTooLarge)?;
240 
241         let nameoff = self.intern_string(name_cstr);
242         self.append_u32(FDT_PROP);
243         self.append_u32(len);
244         self.append_u32(nameoff);
245         self.data.extend_from_slice(val);
246         self.align(4);
247         Ok(())
248     }
249 
250     /// Write an empty property.
property_null(&mut self, name: &str) -> Result<()>251     pub fn property_null(&mut self, name: &str) -> Result<()> {
252         self.property(name, &[])
253     }
254 
255     /// Write a string property.
property_string(&mut self, name: &str, val: &str) -> Result<()>256     pub fn property_string(&mut self, name: &str, val: &str) -> Result<()> {
257         let cstr_value = CString::new(val).map_err(|_| Error::InvalidString)?;
258         self.property(name, cstr_value.to_bytes_with_nul())
259     }
260 
261     /// Write a stringlist property.
property_string_list(&mut self, name: &str, values: &[&str]) -> Result<()>262     pub fn property_string_list(&mut self, name: &str, values: &[&str]) -> Result<()> {
263         let mut bytes = Vec::new();
264         for &s in values {
265             let cstr = CString::new(s).map_err(|_| Error::InvalidString)?;
266             bytes.extend_from_slice(cstr.to_bytes_with_nul());
267         }
268         self.property(name, &bytes)
269     }
270 
271     /// Write a 32-bit unsigned integer property.
property_u32(&mut self, name: &str, val: u32) -> Result<()>272     pub fn property_u32(&mut self, name: &str, val: u32) -> Result<()> {
273         self.property(name, &val.to_be_bytes())
274     }
275 
276     /// Write a 64-bit unsigned integer property.
property_u64(&mut self, name: &str, val: u64) -> Result<()>277     pub fn property_u64(&mut self, name: &str, val: u64) -> Result<()> {
278         self.property(name, &val.to_be_bytes())
279     }
280 
281     /// Write a property containing an array of 32-bit unsigned integers.
property_array_u32(&mut self, name: &str, cells: &[u32]) -> Result<()>282     pub fn property_array_u32(&mut self, name: &str, cells: &[u32]) -> Result<()> {
283         let mut arr = Vec::with_capacity(cells.len() * size_of::<u32>());
284         for &c in cells {
285             arr.extend(&c.to_be_bytes());
286         }
287         self.property(name, &arr)
288     }
289 
290     /// Write a property containing an array of 64-bit unsigned integers.
property_array_u64(&mut self, name: &str, cells: &[u64]) -> Result<()>291     pub fn property_array_u64(&mut self, name: &str, cells: &[u64]) -> Result<()> {
292         let mut arr = Vec::with_capacity(cells.len() * size_of::<u64>());
293         for &c in cells {
294             arr.extend(&c.to_be_bytes());
295         }
296         self.property(name, &arr)
297     }
298 
299     /// Finish writing the Devicetree Blob (DTB).
300     ///
301     /// Returns the DTB as a vector of bytes, consuming the `FdtWriter`.
302     /// The DTB is always padded up to `max_size` with zeroes, so the returned
303     /// value will either be exactly `max_size` bytes long, or an error will
304     /// be returned if the DTB does not fit in `max_size` bytes.
305     ///
306     /// # Arguments
307     ///
308     /// `max_size` - Maximum size of the finished DTB in bytes.
finish(mut self, max_size: usize) -> Result<Vec<u8>>309     pub fn finish(mut self, max_size: usize) -> Result<Vec<u8>> {
310         if self.node_depth > 0 {
311             return Err(Error::UnclosedNode);
312         }
313 
314         self.append_u32(FDT_END);
315         let size_dt_struct = self.data.len() as u32 - self.off_dt_struct;
316 
317         let totalsize = self.data.len() + self.strings.len();
318 
319         let totalsize = totalsize.try_into().map_err(|_| Error::TotalSizeTooLarge)?;
320         let off_dt_strings = self
321             .data
322             .len()
323             .try_into()
324             .map_err(|_| Error::TotalSizeTooLarge)?;
325         let size_dt_strings = self
326             .strings
327             .len()
328             .try_into()
329             .map_err(|_| Error::TotalSizeTooLarge)?;
330 
331         // Finalize the header.
332         self.update_u32(0, FDT_MAGIC);
333         self.update_u32(1 * 4, totalsize);
334         self.update_u32(2 * 4, self.off_dt_struct);
335         self.update_u32(3 * 4, off_dt_strings);
336         self.update_u32(4 * 4, self.off_mem_rsvmap);
337         self.update_u32(5 * 4, FDT_VERSION);
338         self.update_u32(6 * 4, FDT_LAST_COMP_VERSION);
339         self.update_u32(7 * 4, self.boot_cpuid_phys);
340         self.update_u32(8 * 4, size_dt_strings);
341         self.update_u32(9 * 4, size_dt_struct);
342 
343         // Add the strings block.
344         self.data.append(&mut self.strings);
345 
346         if self.data.len() > max_size {
347             Err(Error::TotalSizeTooLarge)
348         } else {
349             // Fill remaining data up to `max_size` with zeroes.
350             self.pad(max_size - self.data.len());
351             Ok(self.data)
352         }
353     }
354 }
355 
356 #[cfg(test)]
357 mod tests {
358     use super::*;
359 
360     #[test]
minimal()361     fn minimal() {
362         let mut fdt = FdtWriter::new(&[]);
363         let root_node = fdt.begin_node("").unwrap();
364         fdt.end_node(root_node).unwrap();
365         assert_eq!(
366             fdt.finish(0x48).unwrap(),
367             [
368                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
369                 0x00, 0x00, 0x00, 0x48, // 0004: totalsize (0x48)
370                 0x00, 0x00, 0x00, 0x38, // 0008: off_dt_struct (0x38)
371                 0x00, 0x00, 0x00, 0x48, // 000C: off_dt_strings (0x48)
372                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
373                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
374                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
375                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
376                 0x00, 0x00, 0x00, 0x00, // 0020: size_dt_strings (0)
377                 0x00, 0x00, 0x00, 0x10, // 0024: size_dt_struct (0x10)
378                 0x00, 0x00, 0x00, 0x00, // 0028: rsvmap terminator (address = 0 high)
379                 0x00, 0x00, 0x00, 0x00, // 002C: rsvmap terminator (address = 0 low)
380                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap terminator (size = 0 high)
381                 0x00, 0x00, 0x00, 0x00, // 0034: rsvmap terminator (size = 0 low)
382                 0x00, 0x00, 0x00, 0x01, // 0038: FDT_BEGIN_NODE
383                 0x00, 0x00, 0x00, 0x00, // 003C: node name ("") + padding
384                 0x00, 0x00, 0x00, 0x02, // 0040: FDT_END_NODE
385                 0x00, 0x00, 0x00, 0x09, // 0044: FDT_END
386             ]
387         );
388     }
389 
390     #[test]
reservemap()391     fn reservemap() {
392         let mut fdt = FdtWriter::new(&[
393             FdtReserveEntry {
394                 address: 0x12345678AABBCCDD,
395                 size: 0x1234,
396             },
397             FdtReserveEntry {
398                 address: 0x1020304050607080,
399                 size: 0x5678,
400             },
401         ]);
402         let root_node = fdt.begin_node("").unwrap();
403         fdt.end_node(root_node).unwrap();
404         assert_eq!(
405             fdt.finish(0x68).unwrap(),
406             [
407                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
408                 0x00, 0x00, 0x00, 0x68, // 0004: totalsize (0x68)
409                 0x00, 0x00, 0x00, 0x58, // 0008: off_dt_struct (0x58)
410                 0x00, 0x00, 0x00, 0x68, // 000C: off_dt_strings (0x68)
411                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
412                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
413                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
414                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
415                 0x00, 0x00, 0x00, 0x00, // 0020: size_dt_strings (0)
416                 0x00, 0x00, 0x00, 0x10, // 0024: size_dt_struct (0x10)
417                 0x12, 0x34, 0x56, 0x78, // 0028: rsvmap entry 0 address high
418                 0xAA, 0xBB, 0xCC, 0xDD, // 002C: rsvmap entry 0 address low
419                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap entry 0 size high
420                 0x00, 0x00, 0x12, 0x34, // 0034: rsvmap entry 0 size low
421                 0x10, 0x20, 0x30, 0x40, // 0038: rsvmap entry 1 address high
422                 0x50, 0x60, 0x70, 0x80, // 003C: rsvmap entry 1 address low
423                 0x00, 0x00, 0x00, 0x00, // 0040: rsvmap entry 1 size high
424                 0x00, 0x00, 0x56, 0x78, // 0044: rsvmap entry 1 size low
425                 0x00, 0x00, 0x00, 0x00, // 0048: rsvmap terminator (address = 0 high)
426                 0x00, 0x00, 0x00, 0x00, // 004C: rsvmap terminator (address = 0 low)
427                 0x00, 0x00, 0x00, 0x00, // 0050: rsvmap terminator (size = 0 high)
428                 0x00, 0x00, 0x00, 0x00, // 0054: rsvmap terminator (size = 0 low)
429                 0x00, 0x00, 0x00, 0x01, // 0058: FDT_BEGIN_NODE
430                 0x00, 0x00, 0x00, 0x00, // 005C: node name ("") + padding
431                 0x00, 0x00, 0x00, 0x02, // 0060: FDT_END_NODE
432                 0x00, 0x00, 0x00, 0x09, // 0064: FDT_END
433             ]
434         );
435     }
436 
437     #[test]
prop_null()438     fn prop_null() {
439         let mut fdt = FdtWriter::new(&[]);
440         let root_node = fdt.begin_node("").unwrap();
441         fdt.property_null("null").unwrap();
442         fdt.end_node(root_node).unwrap();
443         assert_eq!(
444             fdt.finish(0x59).unwrap(),
445             [
446                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
447                 0x00, 0x00, 0x00, 0x59, // 0004: totalsize (0x59)
448                 0x00, 0x00, 0x00, 0x38, // 0008: off_dt_struct (0x38)
449                 0x00, 0x00, 0x00, 0x54, // 000C: off_dt_strings (0x54)
450                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
451                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
452                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
453                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
454                 0x00, 0x00, 0x00, 0x05, // 0020: size_dt_strings (0x05)
455                 0x00, 0x00, 0x00, 0x1c, // 0024: size_dt_struct (0x1C)
456                 0x00, 0x00, 0x00, 0x00, // 0028: rsvmap terminator (address = 0 high)
457                 0x00, 0x00, 0x00, 0x00, // 002C: rsvmap terminator (address = 0 low)
458                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap terminator (size = 0 high)
459                 0x00, 0x00, 0x00, 0x00, // 0034: rsvmap terminator (size = 0 low)
460                 0x00, 0x00, 0x00, 0x01, // 0038: FDT_BEGIN_NODE
461                 0x00, 0x00, 0x00, 0x00, // 003C: node name ("") + padding
462                 0x00, 0x00, 0x00, 0x03, // 0040: FDT_PROP
463                 0x00, 0x00, 0x00, 0x00, // 0044: prop len (0)
464                 0x00, 0x00, 0x00, 0x00, // 0048: prop nameoff (0)
465                 0x00, 0x00, 0x00, 0x02, // 004C: FDT_END_NODE
466                 0x00, 0x00, 0x00, 0x09, // 0050: FDT_END
467                 b'n', b'u', b'l', b'l', 0x00, // 0054: strings block
468             ]
469         );
470     }
471 
472     #[test]
prop_u32()473     fn prop_u32() {
474         let mut fdt = FdtWriter::new(&[]);
475         let root_node = fdt.begin_node("").unwrap();
476         fdt.property_u32("u32", 0x12345678).unwrap();
477         fdt.end_node(root_node).unwrap();
478         assert_eq!(
479             fdt.finish(0x5C).unwrap(),
480             [
481                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
482                 0x00, 0x00, 0x00, 0x5c, // 0004: totalsize (0x5C)
483                 0x00, 0x00, 0x00, 0x38, // 0008: off_dt_struct (0x38)
484                 0x00, 0x00, 0x00, 0x58, // 000C: off_dt_strings (0x58)
485                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
486                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
487                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
488                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
489                 0x00, 0x00, 0x00, 0x04, // 0020: size_dt_strings (0x04)
490                 0x00, 0x00, 0x00, 0x20, // 0024: size_dt_struct (0x20)
491                 0x00, 0x00, 0x00, 0x00, // 0028: rsvmap terminator (address = 0 high)
492                 0x00, 0x00, 0x00, 0x00, // 002C: rsvmap terminator (address = 0 low)
493                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap terminator (size = 0 high)
494                 0x00, 0x00, 0x00, 0x00, // 0034: rsvmap terminator (size = 0 low)
495                 0x00, 0x00, 0x00, 0x01, // 0038: FDT_BEGIN_NODE
496                 0x00, 0x00, 0x00, 0x00, // 003C: node name ("") + padding
497                 0x00, 0x00, 0x00, 0x03, // 0040: FDT_PROP
498                 0x00, 0x00, 0x00, 0x04, // 0044: prop len (4)
499                 0x00, 0x00, 0x00, 0x00, // 0048: prop nameoff (0)
500                 0x12, 0x34, 0x56, 0x78, // 004C: prop u32 value (0x12345678)
501                 0x00, 0x00, 0x00, 0x02, // 0050: FDT_END_NODE
502                 0x00, 0x00, 0x00, 0x09, // 0054: FDT_END
503                 b'u', b'3', b'2', 0x00, // 0058: strings block
504             ]
505         );
506     }
507 
508     #[test]
all_props()509     fn all_props() {
510         let mut fdt = FdtWriter::new(&[]);
511         let root_node = fdt.begin_node("").unwrap();
512         fdt.property_null("null").unwrap();
513         fdt.property_u32("u32", 0x12345678).unwrap();
514         fdt.property_u64("u64", 0x1234567887654321).unwrap();
515         fdt.property_string("str", "hello").unwrap();
516         fdt.property_string_list("strlst", &["hi", "bye"]).unwrap();
517         fdt.property_array_u32("arru32", &[0x12345678, 0xAABBCCDD])
518             .unwrap();
519         fdt.property_array_u64("arru64", &[0x1234567887654321])
520             .unwrap();
521         fdt.end_node(root_node).unwrap();
522         assert_eq!(
523             fdt.finish(0xEE).unwrap(),
524             [
525                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
526                 0x00, 0x00, 0x00, 0xee, // 0004: totalsize (0xEE)
527                 0x00, 0x00, 0x00, 0x38, // 0008: off_dt_struct (0x38)
528                 0x00, 0x00, 0x00, 0xc8, // 000C: off_dt_strings (0xC8)
529                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
530                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
531                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
532                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
533                 0x00, 0x00, 0x00, 0x26, // 0020: size_dt_strings (0x26)
534                 0x00, 0x00, 0x00, 0x90, // 0024: size_dt_struct (0x90)
535                 0x00, 0x00, 0x00, 0x00, // 0028: rsvmap terminator (address = 0 high)
536                 0x00, 0x00, 0x00, 0x00, // 002C: rsvmap terminator (address = 0 low)
537                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap terminator (size = 0 high)
538                 0x00, 0x00, 0x00, 0x00, // 0034: rsvmap terminator (size = 0 low)
539                 0x00, 0x00, 0x00, 0x01, // 0038: FDT_BEGIN_NODE
540                 0x00, 0x00, 0x00, 0x00, // 003C: node name ("") + padding
541                 0x00, 0x00, 0x00, 0x03, // 0040: FDT_PROP (null)
542                 0x00, 0x00, 0x00, 0x00, // 0044: prop len (0)
543                 0x00, 0x00, 0x00, 0x00, // 0048: prop nameoff (0)
544                 0x00, 0x00, 0x00, 0x03, // 004C: FDT_PROP (u32)
545                 0x00, 0x00, 0x00, 0x04, // 0050: prop len (4)
546                 0x00, 0x00, 0x00, 0x05, // 0054: prop nameoff (0x05)
547                 0x12, 0x34, 0x56, 0x78, // 0058: prop u32 value (0x12345678)
548                 0x00, 0x00, 0x00, 0x03, // 005C: FDT_PROP (u64)
549                 0x00, 0x00, 0x00, 0x08, // 0060: prop len (8)
550                 0x00, 0x00, 0x00, 0x09, // 0064: prop nameoff (0x09)
551                 0x12, 0x34, 0x56, 0x78, // 0068: prop u64 value high (0x12345678)
552                 0x87, 0x65, 0x43, 0x21, // 006C: prop u64 value low (0x87654321)
553                 0x00, 0x00, 0x00, 0x03, // 0070: FDT_PROP (string)
554                 0x00, 0x00, 0x00, 0x06, // 0074: prop len (6)
555                 0x00, 0x00, 0x00, 0x0D, // 0078: prop nameoff (0x0D)
556                 b'h', b'e', b'l', b'l', // 007C: prop str value ("hello") + padding
557                 b'o', 0x00, 0x00, 0x00, // 0080: "o\0" + padding
558                 0x00, 0x00, 0x00, 0x03, // 0084: FDT_PROP (string list)
559                 0x00, 0x00, 0x00, 0x07, // 0088: prop len (7)
560                 0x00, 0x00, 0x00, 0x11, // 008C: prop nameoff (0x11)
561                 b'h', b'i', 0x00, b'b', // 0090: prop value ("hi", "bye")
562                 b'y', b'e', 0x00, 0x00, // 0094: "ye\0" + padding
563                 0x00, 0x00, 0x00, 0x03, // 0098: FDT_PROP (u32 array)
564                 0x00, 0x00, 0x00, 0x08, // 009C: prop len (8)
565                 0x00, 0x00, 0x00, 0x18, // 00A0: prop nameoff (0x18)
566                 0x12, 0x34, 0x56, 0x78, // 00A4: prop value 0
567                 0xAA, 0xBB, 0xCC, 0xDD, // 00A8: prop value 1
568                 0x00, 0x00, 0x00, 0x03, // 00AC: FDT_PROP (u64 array)
569                 0x00, 0x00, 0x00, 0x08, // 00B0: prop len (8)
570                 0x00, 0x00, 0x00, 0x1f, // 00B4: prop nameoff (0x1F)
571                 0x12, 0x34, 0x56, 0x78, // 00B8: prop u64 value 0 high
572                 0x87, 0x65, 0x43, 0x21, // 00BC: prop u64 value 0 low
573                 0x00, 0x00, 0x00, 0x02, // 00C0: FDT_END_NODE
574                 0x00, 0x00, 0x00, 0x09, // 00C4: FDT_END
575                 b'n', b'u', b'l', b'l', 0x00, // 00C8: strings + 0x00: "null""
576                 b'u', b'3', b'2', 0x00, // 00CD: strings + 0x05: "u32"
577                 b'u', b'6', b'4', 0x00, // 00D1: strings + 0x09: "u64"
578                 b's', b't', b'r', 0x00, // 00D5: strings + 0x0D: "str"
579                 b's', b't', b'r', b'l', b's', b't', 0x00, // 00D9: strings + 0x11: "strlst"
580                 b'a', b'r', b'r', b'u', b'3', b'2', 0x00, // 00E0: strings + 0x18: "arru32"
581                 b'a', b'r', b'r', b'u', b'6', b'4', 0x00, // 00E7: strings + 0x1F: "arru64"
582             ]
583         );
584     }
585 
586     #[test]
nested_nodes()587     fn nested_nodes() {
588         let mut fdt = FdtWriter::new(&[]);
589         let root_node = fdt.begin_node("").unwrap();
590         fdt.property_u32("abc", 0x13579024).unwrap();
591         let nested_node = fdt.begin_node("nested").unwrap();
592         fdt.property_u32("def", 0x12121212).unwrap();
593         fdt.end_node(nested_node).unwrap();
594         fdt.end_node(root_node).unwrap();
595         assert_eq!(
596             fdt.finish(0x80).unwrap(),
597             [
598                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
599                 0x00, 0x00, 0x00, 0x80, // 0004: totalsize (0x80)
600                 0x00, 0x00, 0x00, 0x38, // 0008: off_dt_struct (0x38)
601                 0x00, 0x00, 0x00, 0x78, // 000C: off_dt_strings (0x78)
602                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
603                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
604                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
605                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
606                 0x00, 0x00, 0x00, 0x08, // 0020: size_dt_strings (0x08)
607                 0x00, 0x00, 0x00, 0x40, // 0024: size_dt_struct (0x40)
608                 0x00, 0x00, 0x00, 0x00, // 0028: rsvmap terminator (address = 0 high)
609                 0x00, 0x00, 0x00, 0x00, // 002C: rsvmap terminator (address = 0 low)
610                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap terminator (size = 0 high)
611                 0x00, 0x00, 0x00, 0x00, // 0034: rsvmap terminator (size = 0 low)
612                 0x00, 0x00, 0x00, 0x01, // 0038: FDT_BEGIN_NODE
613                 0x00, 0x00, 0x00, 0x00, // 003C: node name ("") + padding
614                 0x00, 0x00, 0x00, 0x03, // 0040: FDT_PROP
615                 0x00, 0x00, 0x00, 0x04, // 0044: prop len (4)
616                 0x00, 0x00, 0x00, 0x00, // 0048: prop nameoff (0x00)
617                 0x13, 0x57, 0x90, 0x24, // 004C: prop u32 value (0x13579024)
618                 0x00, 0x00, 0x00, 0x01, // 0050: FDT_BEGIN_NODE
619                 b'n', b'e', b's', b't', // 0054: Node name ("nested")
620                 b'e', b'd', 0x00, 0x00, // 0058: "ed\0" + pad
621                 0x00, 0x00, 0x00, 0x03, // 005C: FDT_PROP
622                 0x00, 0x00, 0x00, 0x04, // 0060: prop len (4)
623                 0x00, 0x00, 0x00, 0x04, // 0064: prop nameoff (0x04)
624                 0x12, 0x12, 0x12, 0x12, // 0068: prop u32 value (0x12121212)
625                 0x00, 0x00, 0x00, 0x02, // 006C: FDT_END_NODE ("nested")
626                 0x00, 0x00, 0x00, 0x02, // 0070: FDT_END_NODE ("")
627                 0x00, 0x00, 0x00, 0x09, // 0074: FDT_END
628                 b'a', b'b', b'c', 0x00, // 0078: strings + 0x00: "abc"
629                 b'd', b'e', b'f', 0x00, // 007C: strings + 0x04: "def"
630             ]
631         );
632     }
633 
634     #[test]
prop_name_string_reuse()635     fn prop_name_string_reuse() {
636         let mut fdt = FdtWriter::new(&[]);
637         let root_node = fdt.begin_node("").unwrap();
638         fdt.property_u32("abc", 0x13579024).unwrap();
639         let nested_node = fdt.begin_node("nested").unwrap();
640         fdt.property_u32("def", 0x12121212).unwrap();
641         fdt.property_u32("abc", 0x12121212).unwrap(); // This should reuse the "abc" string.
642         fdt.end_node(nested_node).unwrap();
643         fdt.end_node(root_node).unwrap();
644         assert_eq!(
645             fdt.finish(0x90).unwrap(),
646             [
647                 0xd0, 0x0d, 0xfe, 0xed, // 0000: magic (0xd00dfeed)
648                 0x00, 0x00, 0x00, 0x90, // 0004: totalsize (0x90)
649                 0x00, 0x00, 0x00, 0x38, // 0008: off_dt_struct (0x38)
650                 0x00, 0x00, 0x00, 0x88, // 000C: off_dt_strings (0x88)
651                 0x00, 0x00, 0x00, 0x28, // 0010: off_mem_rsvmap (0x28)
652                 0x00, 0x00, 0x00, 0x11, // 0014: version (0x11 = 17)
653                 0x00, 0x00, 0x00, 0x10, // 0018: last_comp_version (0x10 = 16)
654                 0x00, 0x00, 0x00, 0x00, // 001C: boot_cpuid_phys (0)
655                 0x00, 0x00, 0x00, 0x08, // 0020: size_dt_strings (0x08)
656                 0x00, 0x00, 0x00, 0x50, // 0024: size_dt_struct (0x50)
657                 0x00, 0x00, 0x00, 0x00, // 0028: rsvmap terminator (address = 0 high)
658                 0x00, 0x00, 0x00, 0x00, // 002C: rsvmap terminator (address = 0 low)
659                 0x00, 0x00, 0x00, 0x00, // 0030: rsvmap terminator (size = 0 high)
660                 0x00, 0x00, 0x00, 0x00, // 0034: rsvmap terminator (size = 0 low)
661                 0x00, 0x00, 0x00, 0x01, // 0038: FDT_BEGIN_NODE
662                 0x00, 0x00, 0x00, 0x00, // 003C: node name ("") + padding
663                 0x00, 0x00, 0x00, 0x03, // 0040: FDT_PROP
664                 0x00, 0x00, 0x00, 0x04, // 0044: prop len (4)
665                 0x00, 0x00, 0x00, 0x00, // 0048: prop nameoff (0x00)
666                 0x13, 0x57, 0x90, 0x24, // 004C: prop u32 value (0x13579024)
667                 0x00, 0x00, 0x00, 0x01, // 0050: FDT_BEGIN_NODE
668                 b'n', b'e', b's', b't', // 0054: Node name ("nested")
669                 b'e', b'd', 0x00, 0x00, // 0058: "ed\0" + pad
670                 0x00, 0x00, 0x00, 0x03, // 005C: FDT_PROP
671                 0x00, 0x00, 0x00, 0x04, // 0060: prop len (4)
672                 0x00, 0x00, 0x00, 0x04, // 0064: prop nameoff (0x04)
673                 0x12, 0x12, 0x12, 0x12, // 0068: prop u32 value (0x12121212)
674                 0x00, 0x00, 0x00, 0x03, // 006C: FDT_PROP
675                 0x00, 0x00, 0x00, 0x04, // 0070: prop len (4)
676                 0x00, 0x00, 0x00, 0x00, // 0074: prop nameoff (0x00 - reuse)
677                 0x12, 0x12, 0x12, 0x12, // 0078: prop u32 value (0x12121212)
678                 0x00, 0x00, 0x00, 0x02, // 007C: FDT_END_NODE ("nested")
679                 0x00, 0x00, 0x00, 0x02, // 0080: FDT_END_NODE ("")
680                 0x00, 0x00, 0x00, 0x09, // 0084: FDT_END
681                 b'a', b'b', b'c', 0x00, // 0088: strings + 0x00: "abc"
682                 b'd', b'e', b'f', 0x00, // 008C: strings + 0x04: "def"
683             ]
684         );
685     }
686 
687     #[test]
invalid_node_name_nul()688     fn invalid_node_name_nul() {
689         let mut fdt = FdtWriter::new(&[]);
690         fdt.begin_node("abc\0def")
691             .expect_err("node name with embedded NUL");
692     }
693 
694     #[test]
invalid_prop_name_nul()695     fn invalid_prop_name_nul() {
696         let mut fdt = FdtWriter::new(&[]);
697         fdt.property_u32("abc\0def", 0)
698             .expect_err("property name with embedded NUL");
699     }
700 
701     #[test]
invalid_prop_string_value_nul()702     fn invalid_prop_string_value_nul() {
703         let mut fdt = FdtWriter::new(&[]);
704         fdt.property_string("mystr", "abc\0def")
705             .expect_err("string property value with embedded NUL");
706     }
707 
708     #[test]
invalid_prop_string_list_value_nul()709     fn invalid_prop_string_list_value_nul() {
710         let mut fdt = FdtWriter::new(&[]);
711         let strs = ["test", "abc\0def"];
712         fdt.property_string_list("mystr", &strs)
713             .expect_err("stringlist property value with embedded NUL");
714     }
715 
716     #[test]
invalid_prop_after_end_node()717     fn invalid_prop_after_end_node() {
718         let mut fdt = FdtWriter::new(&[]);
719         let _root_node = fdt.begin_node("").unwrap();
720         fdt.property_u32("ok_prop", 1234).unwrap();
721         let nested_node = fdt.begin_node("mynode").unwrap();
722         fdt.property_u32("ok_nested_prop", 5678).unwrap();
723         fdt.end_node(nested_node).unwrap();
724         fdt.property_u32("bad_prop_after_end_node", 1357)
725             .expect_err("property after end_node");
726     }
727 
728     #[test]
invalid_end_node_out_of_order()729     fn invalid_end_node_out_of_order() {
730         let mut fdt = FdtWriter::new(&[]);
731         let root_node = fdt.begin_node("").unwrap();
732         fdt.property_u32("ok_prop", 1234).unwrap();
733         let _nested_node = fdt.begin_node("mynode").unwrap();
734         fdt.end_node(root_node)
735             .expect_err("end node while nested node is open");
736     }
737 
738     #[test]
invalid_finish_while_node_open()739     fn invalid_finish_while_node_open() {
740         let mut fdt = FdtWriter::new(&[]);
741         let _root_node = fdt.begin_node("").unwrap();
742         fdt.property_u32("ok_prop", 1234).unwrap();
743         let _nested_node = fdt.begin_node("mynode").unwrap();
744         fdt.property_u32("ok_nested_prop", 5678).unwrap();
745         fdt.finish(0x100)
746             .expect_err("finish without ending all nodes");
747     }
748 }
749