diff options
Diffstat (limited to 'src/libstrongswan/bio/bio_reader.c')
| -rw-r--r-- | src/libstrongswan/bio/bio_reader.c | 174 |
1 files changed, 150 insertions, 24 deletions
diff --git a/src/libstrongswan/bio/bio_reader.c b/src/libstrongswan/bio/bio_reader.c index fce0d1aef..3a62bb541 100644 --- a/src/libstrongswan/bio/bio_reader.c +++ b/src/libstrongswan/bio/bio_reader.c @@ -1,4 +1,7 @@ /* + * Copyright (C) 2012 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * * Copyright (C) 2010 Martin Willi * Copyright (C) 2010 revosec AG * @@ -47,8 +50,38 @@ METHOD(bio_reader_t, peek, chunk_t, return this->buf; } -METHOD(bio_reader_t, read_uint8, bool, - private_bio_reader_t *this, u_int8_t *res) +/** + * A version of chunk_skip() that supports skipping from the end (i.e. simply + * reducing the size) + */ +static inline chunk_t chunk_skip_end(chunk_t chunk, size_t bytes, bool from_end) +{ + if (chunk.len > bytes) + { + if (!from_end) + { + chunk.ptr += bytes; + } + chunk.len -= bytes; + return chunk; + } + return chunk_empty; +} + +/** + * Returns a pointer to the data to read, optionally from the end + */ +static inline u_char *get_ptr_end(private_bio_reader_t *this, u_int32_t len, + bool from_end) +{ + return from_end ? this->buf.ptr + (this->buf.len - len) : this->buf.ptr; +} + +/** + * Read an u_int8_t from the buffer, optionally from the end of the buffer + */ +static bool read_uint8_internal(private_bio_reader_t *this, u_int8_t *res, + bool from_end) { if (this->buf.len < 1) { @@ -56,13 +89,16 @@ METHOD(bio_reader_t, read_uint8, bool, this->buf.len); return FALSE; } - *res = this->buf.ptr[0]; - this->buf = chunk_skip(this->buf, 1); + *res = *get_ptr_end(this, 1, from_end); + this->buf = chunk_skip_end(this->buf, 1, from_end); return TRUE; } -METHOD(bio_reader_t, read_uint16, bool, - private_bio_reader_t *this, u_int16_t *res) +/** + * Read an u_int16_t from the buffer, optionally from the end + */ +static bool read_uint16_internal(private_bio_reader_t *this, u_int16_t *res, + bool from_end) { if (this->buf.len < 2) { @@ -70,13 +106,16 @@ METHOD(bio_reader_t, read_uint16, bool, this->buf.len); return FALSE; } - *res = untoh16(this->buf.ptr); - this->buf = chunk_skip(this->buf, 2); + *res = untoh16(get_ptr_end(this, 2, from_end)); + this->buf = chunk_skip_end(this->buf, 2, from_end); return TRUE; } -METHOD(bio_reader_t, read_uint24, bool, - private_bio_reader_t *this, u_int32_t *res) +/** + * Read an u_int32_t (only 24-bit) from the buffer, optionally from the end + */ +static bool read_uint24_internal(private_bio_reader_t *this, u_int32_t *res, + bool from_end) { if (this->buf.len < 3) { @@ -84,13 +123,16 @@ METHOD(bio_reader_t, read_uint24, bool, this->buf.len); return FALSE; } - *res = untoh32(this->buf.ptr) >> 8; - this->buf = chunk_skip(this->buf, 3); + *res = untoh32(get_ptr_end(this, 3, from_end)) >> 8; + this->buf = chunk_skip_end(this->buf, 3, from_end); return TRUE; } -METHOD(bio_reader_t, read_uint32, bool, - private_bio_reader_t *this, u_int32_t *res) +/** + * Read an u_int32_t from the buffer, optionally from the end + */ +static bool read_uint32_internal(private_bio_reader_t *this, u_int32_t *res, + bool from_end) { if (this->buf.len < 4) { @@ -98,13 +140,16 @@ METHOD(bio_reader_t, read_uint32, bool, this->buf.len); return FALSE; } - *res = untoh32(this->buf.ptr); - this->buf = chunk_skip(this->buf, 4); + *res = untoh32(get_ptr_end(this, 4, from_end)); + this->buf = chunk_skip_end(this->buf, 4, from_end); return TRUE; } -METHOD(bio_reader_t, read_uint64, bool, - private_bio_reader_t *this, u_int64_t *res) +/** + * Read an u_int64_t from the buffer, optionally from the end + */ +static bool read_uint64_internal(private_bio_reader_t *this, u_int64_t *res, + bool from_end) { if (this->buf.len < 8) { @@ -112,13 +157,16 @@ METHOD(bio_reader_t, read_uint64, bool, this->buf.len); return FALSE; } - *res = untoh64(this->buf.ptr); - this->buf = chunk_skip(this->buf, 8); + *res = untoh64(get_ptr_end(this, 8, from_end)); + this->buf = chunk_skip_end(this->buf, 8, from_end); return TRUE; } -METHOD(bio_reader_t, read_data, bool, - private_bio_reader_t *this, u_int32_t len, chunk_t *res) +/** + * Read a chunk of data from the buffer, optionally from the end + */ +static bool read_data_internal(private_bio_reader_t *this, u_int32_t len, + chunk_t *res, bool from_end) { if (this->buf.len < len) { @@ -126,11 +174,83 @@ METHOD(bio_reader_t, read_data, bool, this->buf.len, len); return FALSE; } - *res = chunk_create(this->buf.ptr, len); - this->buf = chunk_skip(this->buf, len); + *res = chunk_create(get_ptr_end(this, len, from_end), len); + this->buf = chunk_skip_end(this->buf, len, from_end); return TRUE; } +METHOD(bio_reader_t, read_uint8, bool, + private_bio_reader_t *this, u_int8_t *res) +{ + return read_uint8_internal(this, res, FALSE); +} + +METHOD(bio_reader_t, read_uint16, bool, + private_bio_reader_t *this, u_int16_t *res) +{ + return read_uint16_internal(this, res, FALSE); +} + +METHOD(bio_reader_t, read_uint24, bool, + private_bio_reader_t *this, u_int32_t *res) +{ + return read_uint24_internal(this, res, FALSE); +} + +METHOD(bio_reader_t, read_uint32, bool, + private_bio_reader_t *this, u_int32_t *res) +{ + return read_uint32_internal(this, res, FALSE); +} + +METHOD(bio_reader_t, read_uint64, bool, + private_bio_reader_t *this, u_int64_t *res) +{ + return read_uint64_internal(this, res, FALSE); +} + +METHOD(bio_reader_t, read_data, bool, + private_bio_reader_t *this, u_int32_t len, chunk_t *res) +{ + return read_data_internal(this, len, res, FALSE); +} + +METHOD(bio_reader_t, read_uint8_end, bool, + private_bio_reader_t *this, u_int8_t *res) +{ + return read_uint8_internal(this, res, TRUE); +} + +METHOD(bio_reader_t, read_uint16_end, bool, + private_bio_reader_t *this, u_int16_t *res) +{ + return read_uint16_internal(this, res, TRUE); +} + +METHOD(bio_reader_t, read_uint24_end, bool, + private_bio_reader_t *this, u_int32_t *res) +{ + return read_uint24_internal(this, res, TRUE); +} + +METHOD(bio_reader_t, read_uint32_end, bool, + private_bio_reader_t *this, u_int32_t *res) +{ + return read_uint32_internal(this, res, TRUE); +} + +METHOD(bio_reader_t, read_uint64_end, bool, + private_bio_reader_t *this, u_int64_t *res) +{ + return read_uint64_internal(this, res, TRUE); +} + +METHOD(bio_reader_t, read_data_end, bool, + private_bio_reader_t *this, u_int32_t len, chunk_t *res) +{ + return read_data_internal(this, len, res, TRUE); +} + METHOD(bio_reader_t, read_data8, bool, private_bio_reader_t *this, chunk_t *res) { @@ -202,6 +322,12 @@ bio_reader_t *bio_reader_create(chunk_t data) .read_uint32 = _read_uint32, .read_uint64 = _read_uint64, .read_data = _read_data, + .read_uint8_end = _read_uint8_end, + .read_uint16_end = _read_uint16_end, + .read_uint24_end = _read_uint24_end, + .read_uint32_end = _read_uint32_end, + .read_uint64_end = _read_uint64_end, + .read_data_end = _read_data_end, .read_data8 = _read_data8, .read_data16 = _read_data16, .read_data24 = _read_data24, |