I am not quite familiar with the early history of how UCI file was parsed, but
thought that UCI config files were parsed in a quite clever way all by shell
scripts which made it possible to have multi-line value for options. AFAIK, at
least package openvpn [1] depends on this feature.
This series tries to fix an issue with current C implementation of parser for
UCI config file. The current code uses pointers into line buffer
`ctx->pctx->buf` which may need to grow in size when a backslash was found at
the end of line. The grow is implemented by function uci_realloc() which may
return an address different from the original. Then the parser will be in a
state where ctx->pctx->buf changed, but various char **str and char **target
are not updated along.
The realloc() can be triggered by something like below (in function
parse_double_quote()).
config sockd 'instance0'
option internal_network 'vpn'
option external_network 'wan'
option extra_config "a \
bbbbbbbbbbbbb \
ccccccccccccc \
"
A few test cases, including importing/exporting config, getting/setting option
values were also included trying to verify the patch.
I do not expect this to be accepted in the neare future because at later stage
of preparing this series I saw that LF and NL characters are explicitly deemed
illegal for option value in uci_validate_text(). But if you are interested in
this feature, you can give it a try.
I found multi-line option value useful in cases where I want parts of the
program's configuration values to be connected with OpenWrt system state, e.g.
stop/start services when the status of the dependent network go down/up, while
still keep the related bits all in one place, not just many remedy scripts
scattered here and there.
[1] see `append_params()` in package/network/services/openvpn/files/openvpn.init
Yousong Zhou (4):
Drop test cases for deprecated ucimap-example.
Sync ref test result with current implementation.
Use offset into parser buffer to avoid potential heap overflow.
Add test coverage for multi-line option value.
delta.c | 15 +-
file.c | 216 +++++++++++---------
test/references/add_section.result | 2 +-
test/references/export.data | 7 +-
test/references/export.result | 15 +-
test/references/get_multiline.data | 5 +
test/references/import.data | 7 +-
test/references/import.result | 13 +-
test/references/set_existing_option.result | 2 +-
.../set_existing_option_multiline.result | 2 +
test/references/set_named_section.result | 2 +-
test/references/set_nonexisting_option.result | 2 +-
.../set_nonexisting_option_multiline.result | 2 +
test/references/set_parsing_multiline.data | 2 +
test/tests.d/020_get | 9 +
test/tests.d/030_set | 16 ++
test/tests.d/060-ucimap_example | 9 -
uci_internal.h | 8 +-
util.c | 11 +-
19 files changed, 218 insertions(+), 127 deletions(-)
create mode 100644 test/references/get_multiline.data
create mode 100644 test/references/set_existing_option_multiline.result
create mode 100644 test/references/set_nonexisting_option_multiline.result
create mode 100644 test/references/set_parsing_multiline.data
delete mode 100644 test/tests.d/060-ucimap_example
--
1.7.10.4
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