22 lines
722 B
C
22 lines
722 B
C
#include "asn1.h"
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size_t scan_asn1rawint(const char* src,const char* max,size_t len,long* l) {
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size_t i;
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long m;
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if (src>=max) return 0; // 0 bytes input buffer
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if (*src<0) m=-1; else m=0; // negative number?
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if (len>1 && *src==m) {
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// we want to catch things like 00 01
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// but a leading 0 byte is needed for 00 a0 because otherwise it would be -96
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if ((src[1]>>7)==m) return 0; // non-minimal encoding
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if (len>sizeof(m)+1) return 0; // value too large, does not fit
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} else
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if (len>sizeof(m)) return 0; // value too large, does not fit
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if (src+len>max) return 0; // input buffer not sufficient
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for (i=0; i<len; ++i) {
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m=(m<<8)|(unsigned char)src[i];
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}
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*l=m;
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return len;
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}
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