da36873b76
reject non-minimal encodings for lengths and tags catch too-large-value overflows in tags
16 lines
436 B
C
16 lines
436 B
C
#include "asn1.h"
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size_t scan_asn1tagint(const char* src,const char* max,unsigned long* val) {
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const char* orig=src;
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unsigned long l=0;
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if (src==max || (unsigned char)src[0]==0x80) return 0; /* catch non-minimal encoding */
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for (;; ++src) {
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if (src>=max) return 0;
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if (l>>(sizeof(l)*8-7)) return 0; /* catch integer overflow */
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l=l*128+(*src&0x7F);
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if (!(*src&0x80)) break;
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}
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*val=l;
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return src-orig+1;
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}
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