Updated copyright notices to include the year 2018.

mail-crypt: Do not free global keys if no error has occured

Updated copyright notices to include the year 2017.

global: Replaced all instances of memset(p, 0, sizeof(*p)) with the new i_zero() macro. Used the following script: C_FILES=`git ls-files *.c` H_FILES=`git ls-files *.h` for F in "$C_FILES $H_FILES"; do echo "$F" perl -p -i -e 's/safe_memset\(&\(?([^,]*)\)?,\s*0,\s*sizeof\(\g1\)\)/i_zero_safe(&$1)/g' $F perl -p -i -e 's/safe_memset\(([^,]*),\s*0,\s*sizeof\(\*\g1\)\)/i_zero_safe($1)/g' $F perl -p -i -e 's/memset\(&\(?([^,]*)\)?,\s*0,\s*sizeof\(\g1\)\)/i_zero(&$1)/g' $F perl -p -i -e 's/memset\(([^,]*),\s*0,\s*sizeof\(\*\g1\)\)/i_zero($1)/g' $F done

global: Change string position/length from unsigned int to size_t Mainly to avoid truncating >4GB strings, which might potentially cause some security holes. Normally there are other limits, which prevent such excessive strings from being created in the first place. I'm sure this didn't find everything. Maybe everything could be found with compiler warnings. -Wconversion kind of does it, but it gives way too many unnecessary warnings. These were mainly found with: grep " = strlen" egrep "unsigned int.*(size|len)"

mail-crypt: Add mail-crypt plugin